"8","9","An overview of the Hodgkin-Huxley and FItzHugh-Nagumo models","2006-10-17 16:30:00",NULL,"HA 210","Jim Selgrade","http://www4.ncsu.edu/~selgrade/","NC State",,NULL," ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/me8rlm6204s207mvep1khckp90","2006-10-20 08:33:35",NULL
"9","1","High-Resolution Finite Volume Methods and Applications to Tsunami Modeling","2006-11-10 16:00:00",NULL,"HA 210","Randall LeVeque",NULL,"University of Washington",,NULL,"Hyperbolic systems of partial differential equations often arise when modeling phenomena involving wave propagation or advection flow.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/5q8bodke79r8k30j9l5v3jub04","2006-10-20 08:36:03",NULL
"10","1","Heterogeneous Multi-Scale Methods","2006-11-21 16:00:00",NULL,"HA 210","Bjorn Engquist",NULL,"University of Texas",,NULL,"Continuum simulations of solids or fluids for which some atomistic information is needed are typical example of multi-scale problems with very large ranges of scales. For such problems it is necessary to restrict the simulations on the micro-scale to smaller samples of the full computational domain. The heterogeneous multi-scale method is a framework for developing and analyzing numerical methods that couple computations from very different scales. Local micro-scale simulations on small domains supply missing data to a macro-scale simulation on the full domain. Examples are local kinetic Monte Carlo computations that produce data to a continuum macroscale model, or composite materials with random coefficients for which effective properties are of interest.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/d1r93uh4o9pav19h3jkl73lmus","2006-10-20 08:37:25","2006-10-22 22:07:16"
"11","1","Pressure estimate for the incompressible Navier-Stokes equation","2006-11-15 15:00:00",NULL,"HA 330","Jian-Guo Liu",NULL,NULL,"MATH",NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/8tk9qlu797aibbrp88lpgcl6c8","2006-11-20 10:11:36",NULL
"12","4","Nonclassical multidimensional shocks","2006-11-29 15:00:00",NULL,"HA 330","Mark Williams",NULL,NULL,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kee818pamuuu3bcn9ca1enneuo","2006-11-27 13:46:24","2006-11-28 10:46:47"
"13","8","Exploiting SPARSITY and SYMMETRY in semidefinite programming with applications in polynomial optimization","2006-11-29 15:00:00",NULL,"HA 335","Kartik Sivaramakrishnan",NULL,NULL,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/64csihi51p59tnoov1uoerahp0","2006-11-27 14:02:21","2006-11-27 23:26:32"
"14","6","Virtual material design of elastic materials & applications EJIIM for linear elastic systems","2006-11-28 15:00:00",NULL,"HA 330","Vita Rutka",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/subt7bmvev69irjed50cfp5m60","2006-11-27 23:22:31",NULL
"16","11","Call center operations risk modeling- Potential impact of Avian flu","2006-12-01 13:30:00",NULL,"1206 Nelson","Debra Elkins",NULL,"General Motors R&D Center",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hsfl4mat28k0v79r5aq1l0rgvo","2006-12-01 02:30:50","2006-12-01 10:04:08"
"17","3","Logarithmic tensor product theory","2006-12-01 15:00:00",NULL,"HA 335","Yi-Zhi Huang",NULL,"Rutgers University",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/63mu11i6dhl9v2pkjvqno0cp7o","2006-12-01 02:50:24","2006-12-01 13:58:43"
"20","14","Mathematics Departmental Meeting","2007-01-11 16:00:00",NULL,"HA 201",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/26nrhghh8v5vk2spn2br1akerg","2007-01-02 10:23:43",NULL
"26","4","Upper bounds on the coarsening rates of discrete ill-posed nonlinear diffusions","2007-01-12 15:00:00",NULL,"HA 335","John Greer",NULL,"Courant Institute, New York University",,NULL,"I will discuss a recent proof of a weak upper bound on the coarsening rate of the discrete-in-space version of an ill-posed, nonlinear diffusion equation.  The continuum version of the equation violates parabolicity and lacks a complete well-posedness theory.  In particular, numerical simulations indicate very sensitive dependence on initial data.  Nevertheless, models based on its discrete-in-space version, which I will discuss, are widely used in a number of applications, including population dynamics (chemotactic movement of bacteria), granular flow (formation of shear bands), and computer vision (image denoising and segmentation).  The bounds have implications for all three applications. This is joint work with Selim Esedoglu (U. of Michigan Mathematics).

Dr. Greer is a candidate for an assistant professorship in the mathematics department.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cmt0tskaa1um9giqnsqs2fp7d4","2007-01-11 22:54:35","2007-01-11 23:15:41"
"28","4","Analysis and computations for viscoelastic fluids","2007-01-19 14:00:00",NULL,"HA 330","Becca Thomases",NULL,"Courant Institute, New York University",,NULL,"Viscoelastic flow modeled by the Oldroyd-B equations will be discussed from an analytical and numerical perspective. First I will present a local energy decay theorem which applies to a large class of hyperbolic systems including the Oldyoryd-B model. This decay theorem is used to prove that global smooth solutions exist for small initial data. While small solutions are global, the problem for large data is much more complicated. I will present numerical work on the Oldroyd-B equations 
which indicates that the system develops singularities exponentially in time at hyperbolic stagnation points in the flow.  The singularities arise in the stress field of the flow and the algebraic structure of these singularities depends critically on an important elasticity parameter, the Weissenberg number.  A local approximation to the solution at the hyperbolic stagnation point is constructed and there is excellent agreement between the local solution and the simulations.

Faculty, students and post-docs are encouraged to attend.

Dr. Thomases is a candidate for an assistant professorship in the 
mathematics department.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v69u584b6tpbll8chbp65mvouc","2007-01-15 20:16:58",NULL
"29","4","Hyperbolic Systems with Dissipation","2007-01-22 15:00:00",NULL,"HA 335","Cleopatra Christoforou",NULL,"Northwestern University",,NULL,"I will begin with an introduction to the theory of hyperbolic conservation laws emphasizing the major challenges, construction methods and most recent developments. The second part of the talk will be devoted to global entropy weak solutions of systems of conservation laws with dissipation constructed via the vanishing viscosity method. I will present results of existence, uniqueness and stability for systems with (i) dissipative source and (ii) fading memory. Last, I will show that the vanishing viscosity method is an effective tool to establish the relaxation limit.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vd9bo9u92d2pct8qrncgv6nhs8","2007-01-19 10:43:49",NULL
"30","6","The Mathematics behind Google PageRank","2007-01-30 15:00:00",NULL,"HA 330","Ilse Ipsen","http://www4.ncsu.edu/~ipsen","NC State",,NULL,"How does Google decide in which order to display web pages as the result of a search? A major ingredient in this decision is PageRank, which is a score associated with every web page. Increasing the PageRank of a web page has become an important factor in many marketing strategies.
PageRank only depends on the links among web pages, but not on their content. Mathematically, PageRank can be viewed as the stationary distribution of a stochastic matrix whose dimension is now in the tens of billions. Hence the computation of PageRank if often referred to as the world\'s largest matrix computation.

We discuss the mathematical problem behind PageRank; its numerical computation; the effect on PageRank of adding and removing links; and how to deal with web pages, such as jpg or pdf files, that contain no links to other web pages. We also discuss the performance of traditional numerical approaches with regard to correct ranking of web pages. 
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q87nmnou424j1tk86ujboht9n8","2007-01-29 11:05:19",NULL
"32","6","Finite Element Models of Biphasic Deformation in the Cellular Microenvironment of Articular Cartilage","2007-02-13 15:00:00",NULL,"HA 330","Mansoor Haider","http://www4.ncsu.edu/~mahaider","NC State",,NULL,"Articular cartilage can be idealized as a biphasic (fluid-solid) mixture that is comprised of a solid extracellular matrix saturated by interstitial fluid. Cartilage extracellular matrix is maintained by a sparse population of cells called chondrocytes. Since cartilage contains no blood vessels or nerve endings, metabolic activity of the chondrocytes is highly dependent upon mechanical characteristics of the local pericellular environment. However, relationships between microscale and macroscale biphasic mechanical variables are not well understood. In this talk, computational models for biphasic deformation in the cartilage pericellular microenvironment will be presented. This environment is modeled as a three-zone biphasic domain consisting of a cartilage cell, its encapsulating pericellular matrix, and the surrounding extracellular matrix. Computational models were developed using an axisymmetric biphasic finite element method, based on a displacement-velocity-pressure penalty formulation, and were implemented as a customized model in COMSOL Multiphysics. Simulations will be presented for biphasic deformation at the microscopic cellular scale in a cartilage layer subjected to dynamic compressive loading at the macroscopic scale. Implications for modeling osteoarthritis will also be discussed. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8thg5p05kvl1mk8nqbha90gmf0","2007-01-29 11:07:47",NULL
"33","8","Nonclassical equivalence transformations","2007-03-29 16:15:00",NULL,"HA 274","Nicoleta Bila",NULL,"Fayetteville State University",,NULL,"Many natural phenomena are described by nonlinear partial differential equations which are often difficult to be solved analytically as there is no existing generaltheory for completely solving nonlinear differential equations. In this talk I will present a class of symmetry reductions, called nonclassical equivalence transformations, that can be used to find new analytical solutions of certain nonlinear mathematical models represented by parameter identification problems.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d7vere3045ubskl75vq20qblto","2007-01-29 12:56:55","2007-03-27 10:15:55"
"34","8","The Parallel Approximation Problem","2007-04-12 15:00:00",NULL,"HA 330","Gabor Pataki",NULL,"UNC Chapel Hill",,NULL,"We study a basic problem, that we call \""Parallel Approximation\"":
\""Given an integral vector a, find an integral vector p, which has much smaller norm than a, while being almost parallel to it\"". Of course, \""almost parallel needs to be carefully defined: roughly it means that the vector a has a decomposition a = lambda*p + r, where lambda is rational, lambda is large, and the norm of the remainder vector r is small compared to the norm of a.

In a more general version, a should be approximated with a combination of k integral vectors. We prove a bound on the quality of the approximaton, and show one application: if in a subset sum problem the left hand side vector (the vector of the item weights) has sufficiently large norm, then for almost all right hand sides the problem has a simple proof of infeasibility. This result is related to the work of Lagarias and Odlyzko and Furst and Kannan on subset sum.

Our original motivation comes from Integer Programming, but in a sense Parallel Aproximation is a well solved problem in search of applications: it is quite possible that it will find uses in other areas of computational mathematics.

Joint work with Mustafa Tural at UNC Chapel Hill.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lka4o5uhu7p2tt2jeimainlb8c","2007-01-29 12:57:39","2007-04-04 16:39:53"
"35","9","Does species diversity drive community production or vice versa? Towards a unification of historical and contemporary paradigms","2007-01-16 16:30:00",NULL,"200 Cox Hall","Kevin Gross",NULL,"NC State",,NULL,"Studies examining the relationship between species diversity and the productivity of ecological communities have taken one of two opposite viewpoints, either viewing productivity as a primary driver of diversity, or diversity as a driver of productivity. Recently, verbal and graphical hypotheses have been proposed that attempt to merge these perspectives by clarifying the causal pathways that link resource supply 
rates, species diversity, resource use and biomass production. Here we present a mathematical model that formalizes how these pathways can operate simultaneously in a single ecological system. Using a metacommunity model in which classic consumer-resource theory governs species interactions within patches, we show that the mechanisms by which resource loading influences species diversity are inherently linked to the mechanisms by which species diversity controls resource 
use and biomass production. Unlike prior hypotheses, our model shows that resource loading can affect diversity and diversity can affect productivity simultaneously at a single spatial scale. Our model also reproduces scale-dependent associations between species diversity and community biomass that have been reported elsewhere. By detailing the rich network of pathways by which resource supply rates, resource use, 
and species diversity are connected, our model moves closer towards resolving the nature of causality in diversity productivity relationships.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0pibpb7sbhl1kfdgdqnm6slf8g","2007-01-29 13:02:39",NULL
"36","9","Modeling in the Biological and Biomedical Sciences","2007-01-23 16:30:00",NULL,"200 Cox Hall","H. T. Banks",NULL,"NC State",,NULL,"We give a survey of several ongoing research projects. Time permitting, we shall discuss (i) Use of shrimp protein synthesis pathways for the rapid production of anti-toxins in response to population attacks (either deliberate or inadvertent);  (ii)  Investigation of  sublethal as well as lethal damage due to pesticides/insecticides in pea aphid populations; and (iii) Models with predictive capabilities in the progression of HIV. Each of the projects involve mathematics, statistics and the use of inverse problem techniques and represent significant collaborations of our group with appropriate  scientists from biological biomedical teams.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mcuno2rrfuucsded1oqe4s6p8g","2007-01-29 15:27:49",NULL
"37","9","Multistable Dynamics Mediated by Tubuloglomerular Feedback in a Model of Coupled Nephrons","2007-01-30 16:30:00",NULL,"200 Cox Hall","Anita Layton",NULL,"Duke University",,NULL,"To help elucidate the causes of irregular tubular flow oscillations found in the nephrons of spontaneously hypertensive rats (SHR), we have conducted a bifurcation analysis of a mathematical model of two nephrons that are coupled through their tubuloglomerular feedback (TGF) systems. This investigation was motivated by a modeling study which predicts that NaCl backleak from a nephron\'s thick ascending limb permits multiple stable oscillatory states that are mediated by TGF (Am. J. Physiol. Renal Physiol. 291: F79-F97, 2006). In that study, a characteristic equation obtained via linearization from a single-nephron model having NaCl backleak, in conjunction with numerical solutions of the full, nonlinear model equations for two and three coupled neph rons, was used in the formulation of a comprehensive, multifaceted hypothesis for the emergence of complex dynamics in SHR. In the present study we have derived a characteristic equation for a model of an arbitrary number of mutually coupled nephrons having NaCl backleak. Analysis of that characteristic equation for the case of two coupled nephrons has revealed a number of parameter regions having the potential for differing stable dynamic  states. Numerical solutions of the full equations for two model nephrons exhibit a number of differing behaviors in these regions. Some behaviors are markedly irregular and exhibit a degree of spectral complexity that is consistent with physiologic experiments in SHR. Effects of coupling and irregular oscillations on fluid and NaCl delivery are also discussed.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jk0qk5uj744di2p60j55k2ltak","2007-01-29 15:30:11","2007-01-29 15:34:36"
"38","2","Flows, bumps, and flexibility: Fish fins, whale flippers, and more","2007-02-01 15:00:00",NULL,"HA 330","Silas Alben",NULL,"Harvard University",,NULL,"No abstract.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eq6vbbldupiq82b4q8fvp9uors","2007-01-29 15:31:37","2007-03-19 13:19:09"
"39","3","Boson type realizations of 4-point algebras","2007-01-19 15:00:00",NULL,"HA 335","Ben Cox",NULL,"College of Charleston",,NULL,"Motivated by work of D. Kazhdan and G. Lusztig on tensor categories, and the work of M. Schlichenmaier and O.K. Sheinman on quasi-graded Lie algebras and their representation theory, Murray Bremner introduced the notion of n-point algebras in 1994. Starting with his description of a 4-point algebra in terms of generators and relations we will describe new free field or boson type realizations of these algebras using ideas of Jakobsen and Kac and Bernard and Felder. 
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d3d6rpb7baj2kkq1n596lb4sss","2007-01-30 10:30:03",NULL
"40","3","The binomial essence of lecture hall partitions","2007-02-02 15:00:00",NULL,"HA 335","Carla Savage",NULL,"NC State",,NULL,"A lecture hal l partition is a sequence x1 , x2 , . . . , xn of nonnegative integers satisfying the linear inequalities: x1 /n ? x2 /(n ? 1) ? . . . ? xn /1. Lecture hall partitions were introduced in 1997 by Bousquet- Melou and Eriksson who showed that they are in one-to-one correspondence with partitions into odd parts less than 2n. Since then, several generalizations and refinements of this result have been discovered. In this talk we view lecture hall partitions from three different perspectives (integer-analogs, q-series identities, and Sylvester’s bijection) to uncover some new connections. 
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/64iabbbuo31ejb655s1cc4stuk","2007-01-30 10:31:00",NULL
"41","9","Physiologically based pharmacokinetic modeling in aging humans: Early issues and examples","2007-02-06 16:30:00",NULL,"Cox 200","Karen Yokley",NULL,"UNC Chapel Hill",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p4esama5uf07euogm22sodbjmk","2007-02-05 16:52:07",NULL
"42","10","Optimal control of populations using impulsive culling","2007-02-06 16:30:00",NULL,"Daniels 406","Robert E. White","http://www4.ncsu.edu/~white","NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8iosk72v7pvgdc4lrbcqukl4no","2007-02-05 16:54:04",NULL
"43","2","Reliable and unreliable dynamics in driven oscillator networks","2007-02-06 15:00:00",NULL,"HA 330","Kevin Lin",NULL,"Courant Institute",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jheml2if9rknmf3bc511ktbau0","2007-02-05 16:55:16",NULL
"44","14","Departmental Tea and Cookies","2007-02-06 14:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/17parg4rkh34r3vu2licanrj34","2007-02-05 16:56:34",NULL
"45","2","Vertex operator algebras and recurrence relations","2007-02-07 15:00:00",NULL,"HA 330","William Cook",NULL,"Rutgers University",,NULL,"Dr. Cook is a candidate for a non-tenure track position as a Teaching Assistant Professor in the department.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ffnk663dfmcigsnc1v6ooh2idk","2007-02-05 16:57:48",NULL
"46","14","Departmental Tea and Cookies","2007-02-07 14:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ji3r056o4o31uvi99t328hel54","2007-02-05 16:58:57",NULL
"47","1","Stability of Black Holes","2007-03-16 16:00:00",NULL,"HA 201","Joel Smoller",NULL,"University of Michigan",,NULL,"We consider decay of solutions of the Cauchy Problem for various fields in the Kerr (rotating Black Hole - BH) geometry. We discuss the formulation of the problem in terms of  the Teukolsky equation, a single second-order PDE depending on a real parameter s, the  \""spin\"".\"" For various values of s, the Teukolsky equation describes different fields in the  Kerr geometry: s=0,1/2,1, 2, correspond, respectively, to scalar waves, Dirac\'s equation,  Maxwell\'s equations, and gravitational waves. We discuss our results for s=0,1/2, as well  as our rigorous proof of Penrose\'s proposal (1969) for energy extraction from a Kerr BH.  In the case of a Schwarzschild (non-rotating) BH, we discuss our decay results, and hence  stability of this BH, for all spin. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/9hq15lik7mrn4ao6r4mjkuekio","2007-02-05 17:02:09","2007-02-05 17:24:07"
"48","1","Solitons, Discovery, Impact and Applications","2007-04-18 16:00:00",NULL,"HA 201","Mark Ablowitz",NULL,"University of Colorado",,NULL,"This lecture will discuss the phenomena of nonlinear localized waves, called solitary  waves or solitons that were first observed in shallow canals in Scotland in 1834. Associated with solitons are a class of nonlinear equations which are linearized via the inverse  scattering transform.  In the 1970’s soliton waves were shown to describe giant internal  waves in the ocean. Localized nonlinear waves are also fundamental in the study of nonlinear optics, such as high bit-rate communications. If time permits another type of nonlinear wave will be discussed. These are \""fully discrete\"" waves, composed of only zero\'s and  one\'s; i.e. cellular automata. There are a class of such discrete waves that have soliton solutions and other interesting behavior. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/motcpqr1v49f00rfq1a1mrko6o","2007-02-05 17:03:35",NULL
"49","8","Canonical representation of rankings and their extension","2007-02-08 15:00:00",NULL,"HA 330","Oleg Golubitsky",NULL,"University of Western Ontario",,NULL,"A ranking is a total order relation on the Cartesian product of an abelian group and a finite set which is compatible with the group operation. The cases when the abelian group is that of integer, rational, or real m-tuples are of particular interest, since they are directly related to the problem of classification of rankings on partial derivatives, and the latter play an important role in constructive differential algebra.

When the finite set in the above Cartesian product consists of one element, rankings become group orders. Every order on the group of integer m-tuples extends uniquely to an order on rational m-tuples, which in turn extends (not necessarily uniquely) to an order on real m tuples. This chain of extensions gives a complete characterization of orders on integer m-tuples in terms of real matrices and, consequently, allows to classify admissible monomial orderings.

Applying the results of G. Carra Ferro, W. Sit, C. Rust, and G. Reid, we propose a canonical representation of rankings by finite trees of Riquier pre-rankings. We also propose a canonical representation of Riquier pre-rankings by real matrices. Finally, we prove that every ranking over integer m-tuples can be extended to a ranking over rational m-tuples, and every ranking over rational m-tuples can be extended to a ranking over real m-tuples. Both extensions are not unique.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bvsem23n6drf044ns5uen1vio8","2007-02-06 11:46:24","2007-02-06 15:12:07"
"50","6","TBA","2007-02-27 15:00:00",NULL,"HA 330","Scott McRae",NULL,"NC State",,NULL,"Numerical approximations of conservation laws and other PDEs are typically described in terms of their “order of accuracy.” This usually refers to the exponent of the local mesh/marching step spacing coefficients that appear in the leading term(s) of a Taylor series expansion of the complete approximation. Assuming approximation consistency, this classification is usually considered to be an indicator of the resolution/accuracy/frequency content (in a Fourier sense) that can be obtained by use of the approximation to solve a problem. 

However, when developed codes using these approximations are examined, dissipative terms are usually found that were added to promote stability, to damp “spurious” waves, to cancel boundary reflections, etc., etc. Since these added terms may be larger in magnitude than the leading truncation error terms and in fact may not be scaled by the mesh spacing, the order of accuracy and mesh spacing no longer provide reliable indicators of the frequency content to be expected in the solution. Instead, a “forensic” analysis of the solution is needed to discover which frequencies potentially resolved by the mesh spacing have been filtered by the sum of all dissipation sources. 

Solutions obtained with an adaptive version of the numerical weather prediction code MM5 will be used to illustrate this issue. A first, simple attempt at forensic analysis using MatLab FFT routines will be presented and the need for more sophisticated analysis will be discussed.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3lbrl2vftrkadf3alg3lcsqui0","2007-02-06 15:07:51",NULL
"51","6","Modeling Core-Collapse Supernovae","2007-03-13 15:00:00",NULL,"HA 330","John Blondin",NULL,"NC State",,NULL,"Computational physics has been the leading tool in a 40-year effort to understand how massive stars end their lives in a supernova explosion. Numerical models have led to many discoveries, including the role of neutrino heating to rejuvenate the shock, thermally-driven convection behind the shock, and the instability of the shock itself. Our efforts here at NC State have focussed on using computational gas dynamics to investigate the evolution of the nascent supernova shock wave when it is still buried deep in the core of the dying star. Using the new Cray supercomputers at ORNL we have run our models on large 3D grids to discover a new mechanism for spinning up the central pulsar during this supernova explosion, and recent efforts to incorporate nuclear reaction networks appear to be paving a way to finally answer the question of how supernovae explode. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p1p90cf9finseh6qn5ae057lkc","2007-02-06 15:08:53","2007-02-14 11:51:44"
"52","9","The pharmacodynamics of antibiotic treatment","2007-02-20 16:30:00",NULL,"200 Cox Hall","Mudassar Imran",NULL,"NC State",,NULL,"We derive models of the effects of periodic, discrete dosing or constant dosing of antibiotics on a bacterial population whose growth is checked by nutrient-limitation and possibly by host defenses. Mathematically rigorous results providing sufficient conditions for treatment success, i.e., the elimination of the bacteria, as well as for treatment failure, are obtained. Our models can exhibit bi-stability where the infection-free state and an infection-state are locally stable when antibiotic dosing is marginal. In this case, treatment success may occur only for sub-threshold level infections. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3996lcs5not9bldktg2h7jq9pg","2007-02-06 15:15:37","2007-02-19 11:39:12"
"53","9","TBA","2007-02-27 16:30:00",NULL,"200 Cox Hall","Fan Yuan",NULL,"Duke University",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qeg4vfuq2pe20i7rc5e7jende8","2007-02-06 15:19:11",NULL
"54","9","Overview of Computational Toxicology at the U.S. EPA","2007-03-13 16:30:00",NULL,"200 Cox Hall","Rory Conolly",NULL,"US Environmental Protection Agency",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6n6ekqemrr7qqmuhdbb43ar1dk","2007-02-06 15:20:18","2007-03-13 10:33:49"
"55","10","A Parallel Conic Interior Point Decomposition  Approach for Block-Angular Semidefinite Programs","2007-02-20 16:30:00",NULL,"Daniels 401","Kartik Sivaramakrishnan","http://www4.ncsu.edu/~kksivara/","NC State",,NULL,"Semidefinite programming is widely regarded as \""linear programming for the 21st century\"" and has a variety of  applications in science and engineering. Interior point methods (IPMs) are currently the most popular techniques  for efficiently solving semidefinite programs and several software implementations are available. However, current  IPM implementations are fairly limited in the size of semidefinite programs (SDPs) that they can handle.    We will begin with a gentle introduction to semidefinite programming and motivate and present a two stage  decomposition approach for solving semidefinite programs in this talk. In the 1st stage, we exploit the sparsity  and/or the symmetry in the underlying SDP and preprocess it into an equivalent SDP having a \""block-angular\""  structure (we will illustrate the procedures via simple examples). In the 2nd stage we employ a parallel conic  interior point decomposition approach to solve the preprocessed SDP. The idea in this stage is to solve the blockangular SDP using existing interior point methods (IPMs); in an iterative fashion between a master problem (a  mixed conic problem over linear and smaller dimensional semidefinite cones) and \""decomposed\"" and \""distributed\""  subproblems (smaller SDPs) in a parallel and distributed high performance computing environment.    We present our computational experiences with the algorithm on well-known SDPs arising in applications. Our  computations were performed on the distributed \""Henry2\"" cluster at North State University. The talk will be selfcontained and accessible to a general audience.  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4t9vlh77ntk788diqp7l0qt6p4","2007-02-06 15:32:03",NULL
"56","10","Departmental Tea and Cookies","2007-02-20 16:00:00",NULL,"Daniels 401",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pqjv3rkktuidetqpt8k4aldk4g","2007-02-06 15:34:06",NULL
"57","2","Rational surfaces and ranks of elliptic curves","2007-02-12 15:00:00",NULL,"HA 335","Lisa Berger",NULL,"University of Arizona",,NULL,"Dr. Berger is a candidate for a non-tenure track position as a Teaching Assistant Professor in the department.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ljhppd49ain9nfdqs5bsunkqfg","2007-02-12 15:11:03",NULL
"58","14","Departmental Tea and Cookies","2007-02-12 14:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/c938gakgt8fpntmaollagms3oo","2007-02-12 15:11:50",NULL
"59","4","TBA","2007-02-14 15:00:00",NULL,"HA 330","Rachel Levy",NULL,"Duke University",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/63k47kvq5qh2c19mqhe6aq7apg","2007-02-12 15:12:52",NULL
"60","9","Modeling blood lipoprotein metabolism: Understanding mechanisms behind good and bad cholesterol","2007-03-27 16:30:00",NULL,"200 Cox Hall (cancelled)","Laura Potter",NULL,"Glaxo Smith Kline",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fbfdaal1e3p4tekecufodgsgtk","2007-02-14 10:45:56","2007-03-27 14:12:54"
"61","9","TBA","2007-04-03 16:30:00",NULL,"200 Cox Hall","Fred Gould",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p5hhlq224j1sue9lan1mck8h00","2007-02-14 10:46:49",NULL
"62","9","Control Theory and Dose Response Transition in Anti-Stress Gene Regulatory Networks","2007-04-10 16:30:00",NULL,"200 Cox Hall","Qiang Zhang",NULL,"CIIT Centers for Health Research",,NULL,"To maintain a stable intracellular environment cells utilize complex and specialized defense systems against a variety of external perturbations, such as electrophilic stress, heat shock, and hypoxia, etc. Irrespective of the type of stress, many adaptive mechanisms contributing to cellular homeostasis appear to operate through gene regulatory networks that are
organized into negative feedback loops. In general, the degree of deviation of the controlled variables, such as electrophiles,
misfolded-proteins, and O2, is first detected by specialized sensor molecules, then the signal is transduced to specific transcription factors. Transcription factors can regulate the expression of a suite of anti-stress genes, many of which encode enzymes functioning to counteract the perturbed variables. The objective of this study was to explore, using control theory and computational approaches, the theoretical basis that underlies the steady-state dose response relationship between cellular stressors and intracellular biochemical species (controlled variables, transcription factors, and gene products)
in these gene regulatory networks. Our work indicated that the shape of dose response curves (linear, superlinear, or sublinear) depends on changes in the specific values of local response coefficients (gains) distributed in the feedback loop. Multimerization of anti-stress enzymes and transcription factors into homo- dimers, trimers, or even higher-order multimers, play a significant role in maintaining robust homeostasis. Moreover, our simulation noted that dose response curves
for the controlled variables can transition sequentially through four distinct phases as stressor level increases: initial superlinear with lesser control, superlinear more highly controlled, linear uncontrolled, and sublinear catastrophic. Each phase relies on specific gain-changing events that come into play as stressor level increases. The low-dose region is intrinsically non-linear, and depending on the level of local gains, presence of gain-changing events, and degree of feedforward gene activation, this region can appear as superlinear, sublinear, or even J-shaped. The general dose response transition proposed here was further examined in a complex anti-electrophilic stress pathway, which involves multiple genes, enzymes, and metabolic reactions. This work would help biologists and especially toxicologists to better assess and predict the cellular impact brought about by biological stressors.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kv763hbstvdrh96o216m8tfoeo","2007-02-14 10:47:23","2007-04-02 11:47:17"
"64","9","Mechanistic model of steroid biosynthesis to predict biochemical response to endocrine active chemicals","2007-04-24 16:30:00",NULL,"200 Cox Hall","M.S. Breen",NULL,"National Center for Computational Toxicology, US Protection Agency",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6orv7ofpq71d061sipmr62a094","2007-02-14 10:48:58","2007-04-23 14:59:56"
"65","3","Borel subalgebras of gl(infinity)","2007-02-23 15:00:00",NULL,"HA 335","Ivan Dimitrov",NULL,"Queen’s University, Canada",,NULL,"I  will describe all maximal locally solvable subalgebras of gl(infinity), the Lie algebra of finitely infinite matrices. Namely, I will prove that the Borel subalgebras are the stabilizers of a particular type of chains of subspaces of the natural representation of gl(infinity). I will then analyze this result and point out some striking differences between gl(infinity) and the finite dimensional reductive Lie algebras. In particular there are maximal locally solvable subalgebras of gl(infinity) which are also locally nilpotent! The talk will be concluded with a description of some conjectures and open questions. This talk is based on joint works with I. Penkov. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m74e5vpblt1b8fptknrva3pito","2007-02-14 10:50:28","2007-02-19 12:19:13"
"67","2","What is an algebraic variety, and how can we understand them?","2007-02-16 15:00:00",NULL,"HA 335","Davis Doherty",NULL,"University of Washington",,NULL,"We shall define the basic object of study in algebraic geometry: the algebraic variety.   Some basic examples will illustrate the general approach of the field -- considering both algebraic and geometric properties to understand an object.   Applying a somewhat unorthodox method, we shall then try to study a certain \""nice\"" class of varieties.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bbd3r9u6lho3q68pqvrp7qq0do","2007-02-15 14:27:00",NULL
"68","14","Departmental Tea and Cookies","2007-02-16 14:30:00",NULL,"HA 245",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/en7u06bst6bladnc5is59ifsd8","2007-02-15 14:54:51",NULL
"69","8","Extending mechanics to minds","2007-03-01 16:00:00",NULL,"HA 330","Jon Doyle",NULL,"NC State","Erich Kaltofen",NULL,"The study of the mind has stood apart from the study of the physical world for some time. Descartes divided persons into both physical and mental substances, but the mechanics developed subsequently applied only to physical substances. This inapplicability produced a split in the mathematical study of our world, with mathematical theories of continuous differential systems and laws on the physical side, and mathematical theories of logic, probability, utility, and language on the other.

The scientific divorce of mind and body has worked to the disadvantage of the mental sciences, especially in theories of rational behavior exhibited by people and artificial agents. Ideal rationality calls for complete and immediate assimilation of new information, but in the real world people take time to assimilate new information, and assimilation can require noticable effort. Physics has no trouble analyzing resistance to change and effort needed to change in terms of mechanical inertia and work, but psychology and economics have had no recourse to these notions.

We describe how mathematical progress over the past century has set the stage for a reconciliation of the physical and mental sciences that permits analysis of some kinds of minds as mechanical systems complete with actual, non-metaphorical mental forces and mental inertia. Hilbert\\\'s call for development of an axiomatic theory of mechanics produced a revolution in rational mechanics. The axioms supporting this revolution presuppose a continuous physical world, but this presupposition is inessential to the structure of mechanics. We indicate how one can specialize continuum assumptions to physical space, time, and motion, and so broaden the applicability of mechanics
to discrete and hybrid mechanical systems. We illustrate the ideas by identifying forces and masses entering into a simple kind of reasoning agent, and by sketching how mechanical work in such systems provides a measure of mental effort. The mechanical analysis of thinking thus complements the essentially kinematical analysis of computers introduced by Turing, and opens the door to a broad range of mechanical analyses in psychology and economics.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/am2nohdubhatepaafkirp3b4rs","2007-02-16 08:43:53","2007-02-19 13:20:02"
"70","8","On Exact and Approximate Interpolation of Sparse Rational Functions","2007-03-22 15:00:00",NULL,"330 Harrelson Hall","Zhengfeng Yang",NULL,"NC State",,NULL,"The black box algorithm for separating the numerator and the denominator of a multivariate rational function can be combined with sparse multivariate polynomial interpolation algorithms to interpolate a sparse rational function.Randomization and early termination strategies are exploited to minimize the number of black box evaluations. In addition, rational number coefficients are recovered from modular images by rational vector recovery. The need for separate numerator and denominator size bounds is avoided via self-correction, and the modulus is minimized by use of lattice basis reduction, a process that can be applied to sparse rational function vector recovery itself.Finally, one can deploy the sparse rational function interpolation algorithm in the hybrid symbolic-numeric setting when the black box for the rational function returns real and complex values with noise.We present and analyze five new algorithms for the above problems and demonstrate their effectiveness on a benchmark implementation.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tb5s1ahkjalqtoegkroh6jfrfc","2007-02-16 08:46:58","2007-03-21 09:38:20"
"71","14","Departmental Tea and Cookies","2007-02-21 15:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9cp4pqubd6rik6ocoeirt8mfj4","2007-02-19 11:40:41",NULL
"72","9","Understanding tiny insect flight","2007-03-20 16:30:00",NULL,"200 Cox Hall","Laura Miller",NULL,"UNC Chapel Hill",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nl0i85ab30eukt044mguq20od8","2007-02-19 11:47:03","2007-03-19 12:43:19"
"74","15","Preparing for the Job Search","2007-03-01 15:00:00",NULL,"HA 274","Laurie Zack, Rebecca Wills, Tom Braun, Matthew Lasater",NULL,"NC State","SIAM Student Chapter",NULL,"Your fellow graduate students will be discussing their experiences with the job application process in adacemics, industry, and labs.  Additionally we will cover resources for developing your CV, networking, website design, etc.  This is an open panel discussion with FOOD provided! ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mvdsvg4bql9dmiiobbcgipno0s","2007-02-26 09:54:14","2007-03-01 14:02:14"
"75","14","Departmental Tea and Cookies","2007-02-28 15:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ro7r9htrgdo3s0llumkqqehh2o","2007-02-26 13:27:49",NULL
"76","3","Coxeter cones and their h-vectors","2007-03-02 15:00:00",NULL,"HA 335","John Stembridge",NULL,"University of Michigan",,NULL,"Coxeter cones are formed by intersecting the positive sides of a collection of root hyperplanes in some root system. They are (shellable) subcomplexes of the Coxeter complex, and their h-vectors record the distribution of descents among their chambers. We identify a natural class of “graded” Coxeter cones with the property that their h-vectors are symmetric and unimodal, thereby generalizing recent theorems of Reiner–Welker and Branden about the Eulerian polynomials of graded partially ordered sets. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uq6u95te1u6j7h410jfmqlaul4","2007-02-27 10:29:55",NULL
"77","3","Extensions of real-valued characters and Shintani descent","2007-03-16 15:00:00",NULL,"HA 335","Ryan Vinroot",NULL,"University of Arizona",,NULL,"In this talk, we will deal with the finite general linear group, GL(n, q), and the finite unitary group, U(n, q2 ). Both of these groups may be extended by the inverse-transpose automorphism, and the irreducible representations of the original groups which can be extended to irreducibles of the larger group are exactly those which have real-valued characters. We will give a method of evaluating the values of these extended characters on certain elements related to regular unipotent elements in the smaller group. The motivation for this study comes from two places: one is Shintani descent (or base change), and the other is the study of character theory of finite groups of Lie type coming from disconnected groups. This work is joint with R. Gow of University College Dublin. 
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/33g4sltvm4j39suhittgpd449s","2007-02-27 10:33:23",NULL
"78","3","Solving polynomial optimization problems using real algebraic geometry and semidefinite programming","2007-03-23 15:00:00",NULL,"HA 335","Kartik Sivaramakrishnan","http://www4.ncsu.edu/~kksivara/","NC State",,NULL,"Polynomial programming is the problem of optimizing a polynomial function subject to polynomial constraints which describe a semialgebraic set. The general problem is considered intractable and includes discrete and nonconvex problems arising in engineering applications as special cases. In the first half of the talk, we will briefly review two recent approaches due to Lassere (based on moments) and Parrilo (a dual approach based on real algebraic geometry) for solving polynomial optimization problems. They have shown that these approaches yield a hierarchy of semidefinite programming approximations that converge (under certain assumptions) to a global optimal solution to the polynomial program. The semidefinite programming approximations are convex optimization problems that can be solved efficiently using interior point methods. The polynomials arising in practical applications are typically very sparse (few nonzero coefficients) or possess some underlying symmetry (invariant under the action of a group). In the second half of  the talk, we will illustrate (via simple examples) how one can exploit the symmetry/sparsity in the polynomial to obtain smaller/specially structured semidefinite programs. These semidefinite programs can be solved very quickly using decomposition approaches in a parallel computing environment. This enables one to solve larger instances of polynomial optimization problems. The talk will be self contained and accessible to a general audience. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/77spfo5t8i8qgalkr32bdh7nfk","2007-02-27 10:37:38","2007-03-19 13:10:56"
"79","14","Departmental Tea and Cookies","2007-03-15 15:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ea85leptu7f5dn4f5b4u8nbjck","2007-03-13 10:28:08",NULL
"80","5","Jet Bundle Lectures","2007-03-20 16:40:00",NULL,"HA 261","Ronald Fulp",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d35so69ieu5k5cdhs5ofciabjg","2007-03-19 12:44:43",NULL
"81","10","Some optimization applications at SAS Institute","2007-03-20 16:30:00",NULL,"Daniels 218","Manoj Chari",NULL,"SAS Institute",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/aqq4hdoiuotlob2p8o6f5f1g2s","2007-03-19 12:45:36",NULL
"82","14","Departmental Tea and Cookies","2007-03-21 15:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6lkfppfbrhkdau3dob8j3lufu4","2007-03-19 12:46:12",NULL
"83","5","Three descriptions of the first order jet bundle of a fiber bundle","2007-03-27 16:40:00",NULL,"HA 263","Ronald Fulp",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j5crac1eod11214arcbefu3oi8","2007-03-22 13:32:26",NULL
"84","4","The pharmacodynamics of antibiotic treatment","2007-03-29 15:00:00",NULL,"HA 330","Mudassar Imran",NULL,"Department of Population Health and Pathobiology",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qlq762j5i83dafn2e3juo0sqeo","2007-03-26 15:18:42",NULL
"85","14","Departmental Tea and Cookies","2007-03-29 14:30:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/f9k3813sdh3ouduvbvs40kmkto","2007-03-26 15:19:46",NULL
"86","2","A homological obstruction to weak order on trees","2007-03-29 15:00:00",NULL,"HA 335","Patricia Hersh",NULL,"Indiana University",,NULL,"When sorting data on a network of computers, it is natural to ask which data swaps between neighbors constitute progress.  In a linear array, the answer is simple, by virtue of the fact that permutations admit pleasant notions of inversions and weak order.  I will discuss how the topology of chessboard complexes constrains the extent to which these ideas may carry over to other trees; it turns out that there are homological obstructions telling us that a tree does not admit an inversion function unless each node has at least as much capacity as its degree minus one.  On the other hand, we construct an inversion function and weak order for all trees that do meet this capacity requirement, and we prove a connectivity bound conjectured by Babson and Reiner for Coxeter-like complexes along the way.  I will conclude by briefly outlining a program that could perhaps generalize this topological perspective on sorting to all finite graphs.

Dr. Hersh is a candidate for an assistant professor position in our department (general search).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l46v7e62bmkb2inmm42khmeel4","2007-03-26 15:21:09","2007-03-29 14:50:22"
"87","3","Solving polynomial optimization problems using real algebraic geometry and semidefinite programming (part 2)","2007-03-30 15:00:00",NULL,"HA 335","Kartik Sivaramakrishnan","http://www4.ncsu.edu/~kksivara/","NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gq69pbp6csrbbm6kij0toe1om8","2007-03-26 15:22:07",NULL
"88","11,7","Connecting singular and switching controls, with applications in finance","2007-03-30 13:30:00",NULL,"1206 Nelson Hall","Xin Guo",,"UC at Berkeley",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eo60gqcu5u5jogfchd2sfnfcu4","2007-03-26 15:23:55","2008-01-23 13:59:47"
"89","6","Fast Explicit Operator Splitting Method","2007-04-03 15:00:00",NULL,"HA 330","Alexander Kurganov",NULL,"Tulane University",,NULL,"I will first present a fast explicit operator splitting method, recently proposed by Alina Chertock (NC State), Guergana Petrova (Texas A&M University), and myself for (systems of)convection-diffusion equations. The method is based on the Strang operator splitting: the solution operator is approximated by a composition of solution operators of the purely convective and purely diffusive parts of the system. In the case of a linear diffusion, we design a highly accurate operator splitting method by solving the diffusion equation exactly. If, in addition, the diffusion coefficient is small (this corresponds to a convection-dominated case), splitting time-steps can be taken large since the operator splitting error is proportional to the diffusion coefficient. This leads to a very efficient splitting method as it will be illustrated on a number of numerical examples including the polymer system arising in modeling polymer flooding processes in enhanced oil recovery.

The second part of the talk will be devoted to an extension of the proposed method to the Lagrangian framework (joint work with Alina Chertock and Eugene Kashdan from the University of Arizona). The method is applied to the model of propagation of a diffusive pollutant in shallow water: the shallow water equations are solved by a shock-capturing Eulerian method, while the pollutant equation is treated by the operator splitting that combines the method of characteristics for the transport equation and the exact solution operator for the diffusion equation.

Finally, I will present an application of the fast explicit operator splitting method to the models of epitaxial growth of thin films (work in progress with Tao Tang from the Hong Kong Baptist University). In these equation, the diffusion is modeled by a linear fourth-order operator, which, at the diffusion splitting step, is approximated using its spectral representation.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cgid34cj28nnhmpon7bpkr6at8","2007-03-26 15:26:48","2007-04-02 11:43:37"
"90","2","Constrained General Relativity","2007-03-27 15:30:00",NULL,"Dabney 210","James York",NULL,"Cornell University",,NULL,"The  initial value constraints of general relativity have been solved, after remaining unsolved from 1915 until 1999.   The method of solution will be described in this seminar.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/drcp0bnnick8hborrb6thgcdbo","2007-03-26 16:20:56",NULL
"91","14","Departmental Tea and Cookies","2007-04-03 15:50:00",NULL,"HA 243",,NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i8e9l69uo9qrh6v71iml0aqft0","2007-04-02 14:03:44",NULL
"92","8","Hilbert schemes of points","2007-05-10 15:00:00",NULL,"HA 330","Dustin Cartwright",NULL,"UC Berkeley",,NULL,"Hilb_n(X) parametrizes 0-dimensional, degree n subschemes of X. Even for X equal to affine or projective space over an algebraically closed field, Hilb_n(X) can be quite complicated. Much research has been done on the case of smooth surfaces, for which Hilb_n(X) is well-behaved, and in particular smooth. However, while it is known that higher dimensional cases are more complicated, even basic questions are open, such as the irreducibility of Hilb_n(A^3) for many values of n. I will introduce the Hilbert schemes of points, and then present examples illustrating the complex behavior that is possible.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q84qr60ud98lh5qkcphq3abqec","2007-04-04 09:52:34","2007-05-08 10:13:25"
"93","5","The affine structures on the first jet bundle","2007-04-10 16:40:00",NULL,"HA 263","Ronald Fulp",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p0dtlcbilc6a2gd1tbrltupbrg","2007-04-10 08:52:31",NULL
"94","2","Towards a singular gauge theory of mechanics","2007-04-10 15:00:00",NULL,"HA 330","Matthew Perlmutter",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vhhk82ddv0dbii4qefkoa47u24","2007-04-10 08:54:23",NULL
"95","14","Departmental Tea and Cookies","2007-04-10 14:30:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lkhv52ggn358qme0iq89bo1f5o","2007-04-10 08:56:45",NULL
"96","4","Traveling wave solutions of a surfactant equation","2007-04-11 15:00:00",NULL,"HA 330","Vahagn Manukian",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tm20avi4l56e7ntn5dn46nod38","2007-04-10 08:58:39",NULL
"97","3","Fermat curves on weighted projective planes","2007-04-13 15:00:00",NULL,"HA 335","Jeremiah Kermes",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ac7reltqljvme724lc210uofgs","2007-04-10 08:59:48","2007-04-10 09:17:42"
"98","15","Applied Math Panel","2007-04-18 16:30:00",NULL,"HA 274 (Note the unusual time and place!)","Rachel Levy, Matthew Lasater, Derek Culp, Mike McLean",NULL,"Duke University, Sandia Labs/Lincoln Labs/NCSU, SAS, Red Hat","Kelly Dickson",NULL,"Join us for discussion and DINNER Wednesday from 4:30-6pm!  This event will expose graduate students in applied math to future employment options -- including lab, industry, and postdoc positions.  We will have sub sandwiches, chips, cheese and crackers, veggies, fruit, dessert, soda, and more!  Panelists will discuss their jobs institutions and we\'ll have an open floor discussion for audience questions.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mm4nq1bfdsf5pfs76dcuebg3sg","2007-04-12 10:13:42","2007-04-18 13:18:38"
"99","2","Monte Carlo methods for partial differential equations","2007-04-16 15:00:00",NULL,"HA 335","Michael Mascagni",NULL,"Florida State University",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/25kmpq443911psalut1m7l4t08","2007-04-16 22:13:47",NULL
"100","5","The action principle and the Euler-Lagrange equation on jet bundles","2007-04-17 16:40:00",NULL,"HA 263","Ronald Fulp",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b4d9fvjhd0erktl81g0igi1674","2007-04-16 22:14:58",NULL
"101","14","Departmental Tea and Cookies","2007-04-18 15:30:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/saimpmfe8odmkm5c9lhuvdlvo0","2007-04-16 22:15:47",NULL
"102","14","Awards Day Ceremony","2007-04-25 16:00:00",NULL,"HA 201",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mbog1akogcrrnd3sk23qvgqsg8","2007-04-17 10:57:46",NULL
"103","14","Awards Day Reception","2007-04-25 15:30:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rfsm0pc2qvu65nuam2on3lk3r8","2007-04-17 11:00:16",NULL
"104","2","Towards a singular gauge theory of mechanics","2007-04-10 15:00:00",NULL,"HA 330","Matthew Perlmutter",NULL,,,NULL,"The theory of symplectic reduction has proven to be of crucial importance for mechanics and also for symplectic and Poisson geometry. But what happens when the group action is singular? There is a general theory for symplectic manifolds but it does not address the special structure in the case of a cotangent bundle, the most important example from mechanics. This occurs frequently and naturally in examples.

After giving a brief background on symplectic reduction and its applications to mechanics, I will address the problem of singular cotangent bundle reduction.

I will focus on the reduced spaces at zero momentum and present recent results on two new stratifications, not predicted by earlier theory. He is a candidate for the general search, will give the following colloquium today.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/81r1pa2quj51r3120etq8h0324","2007-04-17 11:23:47",NULL
"105","14","Spring 2007 Mathematics Undergraduate Research Presentations","2007-04-26 13:30:00",NULL,"HA 373","Ellie Ransom, Cameron Swofford, Travis Tomlinson, Cameron Lynch",NULL,"NC State",,NULL,"1:30-1:45 Ellie Ransom -  TBA
1:50-2:05 Cameron Swofford - TBA
2:10-2:25 Travis Tomlinson - \""Extending an Example of an A_infinity Algebra\""
2:30-2:45 Cameron Lynch - The Discrete Lyapunov-Malkin Theorem
~2:50pm Refreshments in HA243/245",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8tas7ikh0g3bni2dd46dsggdtc","2007-04-18 09:48:14","2007-04-18 09:49:36"
"106","14","Math Undergraduate Research Presentation Reception","2007-04-26 14:50:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/a3tr1a0bmldlnbb1o70p3oojco","2007-04-23 14:56:15",NULL
"107","5","Formulation of variational symmetries and the Noether theorem on jet bundles","2007-04-24 16:40:00",NULL,"HA 263","Ronald Fulp",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2nqtm2e5nb0lidgsje96pbu5p4","2007-04-23 14:58:00","2007-04-23 14:59:30"
"108","6","The dynamical modeling and simulation of membranes","2007-04-24 15:00:00",NULL,"HA 330","Pingwen Zhang",NULL,"Peking University",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k313na68p3qovuj9h6ovb6pshg","2007-04-23 14:59:09",NULL
"109","14","Departmental Tea and Cookies","2007-05-02 15:45:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/71bdq1jeoocvp8k07460tk46po","2007-05-01 10:34:31",NULL
"110","6"," Automatic Differentiation: Tools & Applications","2007-09-20 16:00:00",NULL,"Progress Energy Lecture Hall, Burlington Engineering Labs","Paul Hovland",NULL,"Argonne National Laboratory","Tim Kelley and Nuclear Engineering",NULL,"We explain automatic differentiation, a family of techniques for transforming a computer subprogram that computes a function into a subprogram that computes the derivatives of that function. We describe available tools for the C and Fortran language families and techniques for using these tools effectively. We illustrate the techniques with several applications, primarily drawn from the geosciences and computational fluid dynamics. We discuss future applications and the effect these applications have on the research agenda. We note that nuclear engineering applications introduce some unique requirements that lead to new solution strategies.We explain automatic differentiation, a family of techniques for transforming a computer subprogram that computes a function into a subprogram that computes the derivatives of that function. We describe available tools for the C and Fortran language families and techniques for using these tools effectively. We illustrate the techniques with several applications, primarily drawn from the geosciences and computational fluid dynamics. We discuss future applications and the effect these applications have on the research agenda. We note that nuclear engineering applications introduce some unique requirements that lead to new solution strategies.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/78sgn0n731v5m4vbruecbfd4dc","2007-08-27 11:16:03",NULL
"111","6","Dynamical Systems and  Non-Hermitian Iterative Eigenvalues","2007-11-13 15:00:00",NULL,"HA 330","Rich Lehoucq",NULL,"Sandia National Laboratories","NA Seminar",NULL,"Our presentation describes an equivalence between certain discrete dynamical systems and a class of iterations for the non-Hermitian eigenvalue problem. The identification of these discrete dynamical systems as approximate solutions of ordinary differential equations reveals important geometric properties that, for example, provide insight into the role of orthogonality and bi-orthogonality. We demonstrate that the continuous systems possess a quadratic invariant and describe the drift associated with the invariant under discretization. We illustrate the critical role played by the quadratic invariant in the convergence theory for the discrete iteration. We also discuss how preconditioning effects the convergence and stability of the dynamical system and its discretization.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/53sl4joa8ke1grdnq36i11tm8g","2007-08-27 13:34:33","2007-10-02 14:09:37"
"112","9","Fall Organizational Meeting","2007-08-28 16:30:00",NULL,"Cox 204",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/363jv70cbo8b91q2c2opadpe8c","2007-08-27 17:52:47",NULL
"113","10","OR orientation and meet new students","2007-08-28 16:30:00",NULL,"Daniels 407",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eilq3fqhmid2r1g43gm9h39u6k","2007-08-27 17:53:51",NULL
"114","14","Departmental Tea","2007-08-29 15:00:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/73dsa5nbj8daem3bthpdg0655c","2007-08-27 17:55:21",NULL
"115","3","Fuss-Catalan combinatorics of finite Coxeter groups","2007-08-31 15:00:00",NULL,"HA 335","Drew Armstrong",NULL,"University of Minnesota",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gkghnv25359mis2glnb8ueja3k","2007-08-27 17:58:25",NULL
"116","8","Rational sums of squares","2007-10-24 15:00:00",NULL,"HA 335","Christopher Hillar",NULL,"Texas A&M University","Agnes Szanto",NULL,"In recent years, techniques from semidefinite programming have
produced numerical algorithms for finding representations of positive
semidefinite polynomials as sums of squares. These algorithms have many
applications in optimization, control theory, quadratic programming, and
matrix analysis. One major drawback with these algorithms is that their
output is, in general, numerical. For many applications, however, exact
polynomial identities are needed. In this regard, Sturmfels has asked
whether a representation with real coefficients implies one over the
rationals. We discuss recent progress on this problem; in particular, we
outline a positive answer to the question for totally real number fields.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ir7n6uckvaenffe42a7ifqm8tg","2007-08-31 14:41:30","2007-10-20 21:32:56"
"117","9","Mathematical Modeling of the Transcriptional Network Controlling the Environmental Stress Response in Saccharomyces cerevisiae","2007-09-04 16:30:00",NULL,"Cox 204","Nathan Wanner",NULL,"NC State",,NULL,"Gene expression is a complex biological process by which cells transcribe their genes into RNA and then translate the RNA into proteins.  Using differential equations and network analysis, we hope to gain a better understanding of how gene expression works in yeast.  First, a transcriptional network was selected using data from the experiment by Lee et. al in 2002.  Using available literature, possible activation/repression relationships were determined.  The dynamics of the network were studied using a nonlinear differential equation developed by Vu and Vohradsky in 2007.  It was showed that initial conditions have no affect on steady-state concentrations in this model, and parameter analysis was performed.  Finally, each gene in the network was systematically deleted, and the steady-state concentrations of the genes in the network were compared to those in the wild-type cell.  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/srdibom3me4r64fuhpds71erds","2007-09-04 11:43:13",NULL
"118","14","Departmental Tea","2007-09-05 15:00:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/tup1vt6dgq4dnsfpjcephq0lr4","2007-09-04 17:44:10",NULL
"119","3","A-infinity algebra structure in cohomology and the rational homotopy type","2007-09-07 15:00:00",NULL,"HA 335","Tornike Kadeishvili",NULL,"Razmadze Mathematical Institute (Republic of Georgia)",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cu4nj82aabjhe428am82b5aenk","2007-09-05 12:15:01",NULL
"120","11","Switching diffusion processes and applications","2007-09-07 13:30:00",NULL,"104 Fox Labs","George Yin",NULL,"Wayne State University",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jvgfgb7c55hn7h9dpp0qored10","2007-09-05 12:15:58",NULL
"121","3","Hives by degenerating triples of flags","2007-09-28 15:00:00",NULL,"HA 335","David Speyer",NULL,"University of Michigan",,NULL,"Knutson and Tao have given a combinatorial formula for GL_n tensor product multiplicities in terms of counting lattice points inside a cone known as the Hive cone. Let R be the ring of functions on G \\times G \\times G that are invariant by the left action of N \\times N \\times N and by the left diagonal action of G. (Where G=GL_n and N is the upper triangular matrices.) Then R has a Z^{3n} dimensional grading such that the dimensions of the graded components of R are the tensor product multiplicities. I will describe a degeneration of R to the semigroup ring of the Hive cone, thus explaining Knutson and Tao\'s result.  If time permits, I will explain joint work with Ezra Miller in which we use this degeneration to compute combinatorial formulas for the Hilbert series of the space of pairs of flags (F_{\\bullet}, G_{\\bullet}) where the dimension of F_i \\cap G_j is required to be at least some fixed constant r_{ij}.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3tuibvkjh0ip8i31pkc4ducfnk","2007-09-06 13:48:25","2007-09-20 15:43:07"
"123","9","Computational modeling of multiphasic micromechanics in articular cartilage","2007-09-11 16:30:00",NULL,"Cox 204","Eunjung Kim",NULL,"NC State, Mathematics Graduate Student","Mette Olufsen",NULL,"Abstract available at
http://www.ncsu.edu/biomath/seminars.html",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dp050rb5h25k1khus3vvb81peo","2007-09-06 14:53:43","2007-09-07 09:10:06"
"124","12","The Challenges of Analysing Outbreaks of Infectious Diseases","2007-09-18 16:30:00",NULL,"Radisson Hotel, 3rd Floor Room F-G RTP","Christl A. Donnelly",NULL,"Imperial College London",,NULL,"Outbreaks of infectious diseases can cause considerable risks to public health and associated alarm throughout communities.  Analysing an outbreak of a novel infectious agent or a well known infectious agent in a novel setting provides challenges to statisticians and quantitative epidemiologists because: there is considerable pressure for immediate answers to both biological and public health questions; little data are available early on; and what data are available have biases in that patients with the longest times, for example from infection to showing symptoms, are less likely to appear in the earliest available data. Increasingly sophisticated statistical methods have been developed to provide unbiased estimates of key epidemiological parameters in “real time”.  As ever, sound science-based public health decisions depend on the quality of the available data, the suitability of the analytical methods, and the understanding by policy makers of the required assumptions as well as the uncertainty associated with the results obtained.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r6bnfsagdnc5qbaleuc6isqjlg","2007-09-10 11:12:09",NULL
"125","3","A-infinity and L-infinity algebras in the context of brace algebras","2007-09-14 15:00:00",NULL,"HA 335","Tom Lada","http://www4.ncsu.edu/~lada","North Carolina State University",,NULL,"We will consider A-infinity and L-infinity algebras in some detail and explain how they appear in brace and symmetric brace algebras.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/niamvejs3fhe1tgtot8grv7j14","2007-09-10 11:23:26","2007-09-10 11:25:26"
"126","3","Recent computational advances in multivariate statistics with applications to target recognition and genomics","2007-09-21 16:00:00",NULL,"HA 335","Plamen Koev",NULL,"NC State",,NULL,"Multivariate statistical analysis is concerned with observations on several
variables which are thought to possess some degree of interdependence.
Driven by problems in genetics, social sciences, image processing, and
wireless communication, one central computational problem in multivariate
statistical testing is to efficiently compute the distributions of
eigenvalues of random covariance matrices.

While these distributions are available explicitly as (extremely slowly 
converging) series of Schur and Jack functions, the computational efforts 
had been hampered by the fact that a straightforward evaluation of even a 
single Schur or Jack function takes exponential time.

The rich mathematical structure of these functions stemming from 
combinatorics and representation theory had apparently been missed for 
over 40 years.

Recently we developed new algorithms that exploit these very properties of
the Schur and Jack functions to compute them extremely efficiently, thus
solving a major open problem in computational multivariate statistics.
Tasks that used to take weeks now take factions of a second.

I will present the key algebraic ideas behind our algorithms (as well as 
certain remaining challenges), including connections with the 
representations of the general linear group and Fast Fourier Transforms. 
I will describe the new applications that have been enabled, particularly 
in Genomics and 3D Target Classification.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7ga5h9c0885tlue0rkc61f7il8","2007-09-10 11:27:15","2007-09-18 12:53:53"
"127","4","Some Results on Limit Cycle Bifurcations for Near-Hamiltonian Systems","2007-09-12 15:00:00",NULL,"HA 330","Maoan Han",NULL,"Shanghai Normal University, China","Xiao-Biao Lin",NULL,"The last part of the 16th Hilbert problem is about the maximal number of limit cycles and their distributions for polynomial systems of degree n on the plane. Much work has been done related to the problem; however it is still open for n>1.  A closely related problem posed by Arnold is to study the maximal number of zeros of an Abelian integral, which is called the weak 16th Hilbert problem. The study of this problem helps to give a lower or upper bound on the number of limit cycles of some near-Hamiltonian systems in many cases. In this talk we outline our methods for finding limit cycles for general near-Hamiltonian systems by perturbing a homoclinic or a double-homoclinic loop, or a center point by using the coefficients of expansions of the Abelian integral or by changing the stability of the loop. Using this method one can give a lower bound on the number of limit cycles for some near-Hamiltonian systems. We also discuss the new development of the method applicable to some cases with a nilpotent singular point.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0bl5d9fsk8kl3ae6qeh6o99r6s","2007-09-10 14:26:23",NULL
"128","10","Production planning with resources subject to congestion","2007-09-11 16:30:00",NULL,"Daniels 407","Reha Uzsoy",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9i99vccm4eal1r4bcf0lnbka18","2007-09-11 09:57:21",NULL
"129","14","Departmental Tea","2007-09-12 15:50:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qs46hl9k7193qmi6n452cl36m4","2007-09-11 09:58:30",NULL
"130","15","Argonne Student Talk and Pizza Social","2007-09-20 17:30:00",NULL,"1202 Burlington","Paul Hovland",NULL,"Argonne National Lab","Kelly Dickson/Gabe Ramos",NULL,"Join SIAM and American Nuclear Society for FREE PIZZA while Paul discusses current projects at Argonne as well as his personal experiences during his time there.  This is an excellent forum for students to learn about career opportunities at Argonne and other similar national labs.  

Please RSVP to kidickso@ncsu.edu so that we can guarantee enough pizza for everyone!",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/et2bmmdat7jj88bt43jhgqh5ec","2007-09-11 14:53:53",NULL
"131","6","Direct Computation of Inverse Potential Problems with Interior Data","2007-10-23 15:00:00",NULL,"HA 330","Isaac Harari",NULL,"Tel Aviv University","Semyon Tsynkov",NULL,"The inverse problem of heat conduction provides a model for many
applications governed by diffusion equations, for which interior
data are available.  We wish to find the single, unknown, thermal
conductivity field by direct (i.e. non-iterative) computation.
This approach requires at least two interior temperature fields.
The strong form of the problem is governed by two partial differential
equations of pure advective transport.  The given temperature fields
must satisfy a compatibility condition for the problem to have
a solution.  The standard weak (variational) form does not provide
a suitable basis for finite element computation.  A conventional
least-squares variational approach yields a well-posed problem, but
does not perform well numerically.

We introduce a novel variational formulation, the Adjoint Weighted
Equation (AWE), for solving the two-field problem.  In this case, the
problem is well posed when the gradients of the two given temperature
fields are linearly independent in the entire domain, a weaker condition
than the compatibility required by the strong form.  The solution of
the AWE formulation is equivalent to that of the strong form when both
are well posed.  The Galerkin discretization of the AWE formulation
converges with optimal rates.  Computational examples confirm these
optimal rates, and demonstrate superior performance to conventional
numerical methods on problems with both smooth and rough coefficients
and solutions.

This work was done in collaboration with Assad Oberai of RPI and Paul
Barbone of BU.  We are currently extending these ideas to problems of
incompressible elasticity.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/29m3d3eqc7a6gv61ua1j9679r0","2007-09-14 14:29:25","2007-10-12 16:30:33"
"133","6","Semi-Lagrangian contouring and elliptic systems","2007-10-02 15:00:00",NULL,"HA 330","John Strain",NULL,"University of California Berkeley","Zhilin Li",NULL,"Many moving interface problems evolve complex material interfaces through topological changes, under velocities determined by elliptic systems of partial differential equations.  A combination of semi-Lagrangian contouring, fast distance finding and Ewald summation yields robust efficient methods for such problems.  High-resolution computations with geometric, Stokes and viscoelastic flows exhibit merging, anisotropy, faceting, curvature, dynamic topology and nonlocal interactions.

The interface motion is converted to a contouring problem with an explicit second-order semi-Lagrangian advection formula.  Grid-free adaptive refinement resolves complex interface geometry.  A fast new Voronoi-based algorithm computes distances to high-order interface patches. Elliptic systems are solved by a fast new locally-corrected boundary integral formulation derived by Ewald summation and accelerated by new geometric nonequidistant fast Fourier transforms.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/of8e5ste1s01ge4ahbf0973vk4","2007-09-14 14:33:24","2007-10-02 14:11:27"
"134","14","Departmental Tea and cookies","2007-09-19 15:00:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mraefmgujf2vdr0d990up9u1gs","2007-09-17 12:27:15",NULL
"135","9","Sensitivity functions and their uses in parameter estimation problems","2007-09-18 16:30:00",NULL,"Cox 204","Sava Dediu",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ems1gpu8gb3gj4hfq06p0t4okg","2007-09-18 10:03:55",NULL
"136","10","Stochastic optimization of a multi-OR surgical suite","2007-09-21 16:30:00",NULL,"Daniels 407","Brian Denton",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6ckb6l8ffbvpn617ss8eb15oa4","2007-09-18 12:53:26",NULL
"137","3","Unipotent quotients and A^1-contractibility","2007-10-05 15:00:00",NULL,"HA 335","Amassa Fauntleroy","http://www4.ncsu.edu/~amassa/","NC State University",,NULL,"We report on the recent work of Asok, Doran and Kirwan on quotients of free actions of unipotent groups. These lead to examples of exotic A^1-contractible (non affine) quasi-affine varieties. This work is motivated by the topological result that for any n>3, any open contractible (PL or smooth) n-manifold can be constructed as a quotient of R^{n+1} by a free (PL or smooth) R-action.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v8ed0v5tjcqbor1uno84bst798","2007-09-20 17:42:21","2007-09-28 20:12:35"
"138","4","Controlled Lagrangians and Stabilization of Mechanical Systems","2007-09-26 15:00:00",NULL,"HA 330","Dmitry Zenkov","http://www4.ncsu.edu/~dvzenkov/","NCSU",,NULL,"The method of controlled Lagrangians introduces a class of structure-preserving feedback control laws for mechanical systems with symmetry. The key feature of the method is that the closed-loop dynamics remains Lagrangian. Thus, stabilization can be established using energy-based Lyapunov functions. In this talk an overview of the method will be given. The some of the new developments of the method will be exposed. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/up4bkm2gj6uno1ap6i54kku1m4","2007-09-23 00:53:07",NULL
"139","14","Mathematics Alumni Panel","2007-09-26 16:30:00",NULL,"HA 201","Mathematics Graduate Student Association",NULL,"NC State",,NULL,"The Mathematics Graduate Student Association (MGSA) will be hosting a
Mathematics Alumni Panel at 4:30 PM on Wednesday, September 26, 2007 in
Harrelson 201.

Please join us to hear about the job experiences of mathematics department
alumni. Panelists have work experience at WebAssign, the US Naval Academy,
and the EPA.

Neomonde will be catering the event. Their website:
http://www.neomonde.com/home/",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pu19e6ikvdlvkl40ajfmdf1mbc","2007-09-25 10:04:55",NULL
"140","10","Advances in Optimizing Electric Power Dispatch using Mathematical Programming","2007-09-25 16:30:00",NULL,"Daniels 407","William L. Rutz",NULL,"Engineering Director, Global Energy Decisions",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/if8l2jp894id4g6dar5gqiaoss","2007-09-25 10:27:58",NULL
"141","10","Canonical Duality Theory:  A Potentially Powerful Methodology for Solving Challenging Problems in Global Optimization and Complex Systems","2007-10-02 16:30:00",NULL,"Daniels 407","David Y. Gao",NULL,"Virginia Tech",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/spd16qou8dfq2l022it0bfgua8","2007-09-25 10:29:17",NULL
"142","14","Departmental Tea and Cookies","2007-09-26 15:50:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sartc042nfk12osua59bv5gle8","2007-09-25 22:57:30",NULL
"143","9","Comparison of Models of Bacterial Infection in the Intestinal Tract","2007-09-25 16:30:00",NULL,"Cox 204","Althea Smith",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m1ba7a36uf9o6dgf8uj999hnq8","2007-09-25 23:00:03",NULL
"144","9","Blood flow in the circle of willis","2007-10-02 16:30:00",NULL,"Cox 204","Kristen DeVault",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/aailobv2osn4tol79pueklkpgs","2007-09-25 23:00:52",NULL
"145","9","Population-based Streptococcus pneumoniae modeling","2007-10-09 16:30:00",NULL,"Cox 204","Venita Depuy",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/piftoflmp2m6fsh9k6htsj6k30","2007-09-25 23:01:33",NULL
"146","9","Modeling and Analysis of Viscoelastic Properties of Large Arteries","2007-10-16 16:30:00",NULL,"Cox 204","Daniela Valdez-Jasso",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qhu5al6i5ms49qe6or8j0rm1b0","2007-09-25 23:02:21","2007-10-14 22:22:21"
"147","9,10","Tutorial: Parameter estimation techniques and model validation","2007-10-23 16:30:00",NULL,"Daniels 407","Hien Tran","http://www4.ncsu.edu/~tran/","NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cur5896g2tbfprtepa0vmp9o0g","2007-09-25 23:03:18",NULL
"148","9,10","Tutorial: Parameter estimation techniques and model validation","2007-10-30 16:30:00",NULL,"Daniels 407","Hien Tran","http://www4.ncsu.edu/~tran/","NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/opdl4rgv90h4mmvloto3dbgok4","2007-09-25 23:04:16",NULL
"149","9","Mathematical Modeling of Cartilage Regeneration","2007-11-06 16:30:00",NULL,"Cox 204","Sarah Olson",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e82osslnios7pc81jruakalvpo","2007-09-25 23:05:01","2007-11-04 22:58:11"
"150","9","An introduction and overview of COMSOL, a finite element package","2007-11-13 16:30:00",NULL,"Cox 204","Oswaldo Lozoya",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n5ov5nib10hjdni2gromf086qc","2007-09-25 23:05:40",NULL
"152","9","TBA","2007-11-27 16:30:00",NULL,"Cox 204","Matthew Krachey",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u4hpj42m5ovrdti7c80k4m3ik0","2007-09-25 23:06:55",NULL
"153","9","TBA","2007-12-04 16:30:00",NULL,"Cox 204","Drew Pasteur",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o42mtan0qaqrsg55qutgkimebg","2007-09-25 23:07:24",NULL
"154","8","Computational Advances in Random Matrix Theory with Applications to Target Recognition and Genomics","2007-10-17 15:00:00",NULL,"Harrelson 335","Plamen Koev","http://www4.ncsu.edu/~pskoev/","NC State","Agnes Szanto",NULL,"Multivariate statistical analysis is concerned with observations on several variables which are thought to possess some degree of interdependence. Driven by problems in genetics, social sciences, image processing, and wireless communication, hypothesis tests for the type and nature of such interdependencies can be cast as questions on the largest eigenvalues of random covariance matrices.

This is where Random Matrix Theory comes in. It provides explicit expressions for these eigenvalue distributions. Unfortunately these expressions are in terms of the hypergeometric function of a matrix argument--a notoriously slowly converging series of Schur, Jack or zonal polynomials whose efficient computation had eluded researchers for 40 years.

Over the years various computational efforts had failed and, apparently, the rich and very elegant structure of the Schur, Jack, and zonal polynomials stemming from combinatorics and representation theory had been missed.

Recently we developed new algorithms that exploit these very properties of the Schur and Jack polynomials to compute them extremely efficiently, thus solving this central open problem in computational multivariate statistics and Random Matrix Theory. Tasks that used to take weeks now take fractions of a second.

I will present they key algebraic ideas behind our algorithms (as well as certain remaining challenges), including connections with the representations of the general linear group and Fast Fourier Transforms. 

I will describe the new applications that have been enabled, particularly in Genomics and 3D Target Recognition.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9obtkdr1eavfdmurltcn5vee14","2007-09-26 10:00:44","2007-10-08 00:13:29"
"155","14","Departmental Tea and Cookies","2007-10-02 15:50:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pk4iej7dardqpnpjgh2s4n1pps","2007-10-01 12:31:30",NULL
"156","4","Stability Index Bundles in Application to Spectral Stability of Combustion","2007-10-10 15:00:00",NULL,"HA 330","Anna Ghazaryan",NULL,"UNC, Chapel Hill,  and NC State",,NULL,"Wavefronts that  arise in a well known mathematical model for  very high Lewis number combustion  are small perturbations of the front exhibited by the same model but with infinite Lewis number. The question of persistence of the spectrum  of  the front with infinite Lewis number under small singular perturbations  is more complicated. Besides discrete spectrum, the system for any Lewis number  possesses essential spectrum up to the imaginary axis.   We construct Stability Index Bundle for the model with high Lewis number  and use its properties to relate the spectral stability of  wavefronts with very high Lewis number to the spectral stability of the front in the case of infinite Lewis number.
This is a joint project with  Chris K.R.T. Jones.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2nfis8v626n792k3mef5r5sag8","2007-10-01 22:20:53","2007-10-08 00:12:48"
"157","4","Algebraic dichotomies and the stability of Riemann solutions of conservation laws","2007-10-17 15:00:00",NULL,"HA 330","Xiao-Biao Lin",NULL,"NC State",,NULL,"Dichotomies, ordinary or weighted, are important concepts in dynamical systems theory. The most well-known example is the exponential dichotomy where the growth or decay is measured by the weight function $e^{\\mu x}$. Recently, there has been some interest on the stability of waves where the functions involved grow or decay at an algebraic rate $|x|^\\mu$. In this talk we define the so called algebraic dichotomy that may be useful to treat such problems. We discuss basic properties of the algebraic dichotomy, methods of detecting it and calculating the power of the weight function.

We present several examples: (1) The Bessel equation. (2) The $n$-degree Fisher type equation. (3) Hyperbolic conservation laws in similarity coordinates. (4) A system of conservation laws with a Dafermos type artificial viscous regularization. This example motivates our work on algebraic dichotomies. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/of41ngjshnq9osfr61kcvdin58","2007-10-01 22:22:24","2007-10-10 09:44:51"
"158","4","Rip Currents and Wave-Current Interaction","2007-10-31 15:00:00",NULL,"HA 330","Jie Yu",NULL,"Civil Engineering, NC State",,NULL,"Breaking waves generate large-scale surf zone currents, e.g. alongshore and rip currents. These persisting currents provide the primary mechanisms to transport, mix and disperse water, sediment and pollutants in the shallow surf zone, where ocean currents generally do not extend. Rip currents are widely acknowledged as a major beach hazard, accounting for 80% surfzone rescues in the US. Studies in Florida show that rip currents cause more deaths than hurricanes do. Their influence on shoreline erosion and water quality on recreational beaches can be significant. Theoretical understanding of their generation mechanisms, however, has not been satisfactory, in particular on beaches lacking alongshore variability.

In this talk, I will present some recent development in modeling rip current dynamics, addressing the importance of the fully dynamical interactions of waves and currents. The existence of a hydrodynamic instability, due to this mutual interaction and leading to the formation of rip currents on alongshore uniform beaches, calls for particular attention of the multi-scale dynamics when modeling hydro-morphodynamic systems in coastal environment.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dj5d5ijh5fmmsoo2j4feaa09e0","2007-10-01 22:23:25","2007-10-27 03:47:17"
"159","7","Studies on Self-Similar Gaussian Processes","2007-10-22 15:00:00",NULL,"HA 330","Professor Yimin Xiao",NULL,"Michigan State University","Min Kang",NULL,"The class of self-similar Gaussian processes is large and, in particular, includes the limiting
processes for the occupation time of branching particle systems.  However, other than fractional
Brownian motion, most of them have not been well studied. The main reason for this phenomenon
is the lack of knowledge on the dependence structure of general Gaussian self-similar processes.

In this talk we propose a general approach for studying Gaussian self-similar processes.
First we apply the Lamperti transform to derive a stochastic integral representation for a general
Gaussian self-similar process $X$. Then we provide a method for establishing the property of
strong local nondeterminism of $X$.

As applications of this approach, we prove Chung\\\'s law of the iterated logarithm and sharp
H\\\\\\\""older conditions for the local times of $X$.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g2vr7ich0ee03imuovo4f44g94","2007-10-02 14:14:18","2007-10-20 21:31:55"
"160","2","Fixed Points and Critical Points in an SIS Epidemic Model","2007-10-05 09:00:00",NULL,"HA 330","Jeffrey Gaither",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j9c6ha5oo6th09k7di7qmie0sc","2007-10-04 11:16:11",NULL
"161","10","Assessing Dynamic Breast Cancer Screening Policies","2007-11-13 16:00:00",NULL,"Daniels 407","Julie Ivy and Edward P. Fitts",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f6tpc0nr1b66ho3mi173dcb87k","2007-10-08 00:15:59","2007-11-06 12:31:42"
"162","14","Departmental Tea and Cookies","2007-10-10 15:50:00",NULL,"HA 244",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/30027h08v5eq8dgh5sqlckqslc","2007-10-08 11:35:07",NULL
"163","6,8","Semidefinite programming in symbolic-numeric computation","2007-11-07 15:00:00",NULL,"HA 335","Lihong Zhi",NULL,"Chinese Academy of Sciences, Beijing","Erich Kaltofen",NULL,"Approximate polynomial computations such as GCD, factorization and polynomial system solving can be formulated as polynomial or rational function optimization problems with or without constraints. We show how to exploit the special sparse structure of these optimization problems and apply sparse semidefinite programming relaxations to find their global optima.

This is a joint Symbolic Computation and Numerical Analysis Seminar",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9n6gutc8h3i44gc71963rpf1sc","2007-10-08 20:28:54","2007-10-22 15:15:49"
"165","11,15","Graduate School FAQ","2007-10-17 17:30:00",NULL,"HA 201","Ernie Stitzinger, Steve Campbell, and Paul Aspinwall",NULL,"NC State and Duke University","Kelly Dickson",NULL,"Ernie Stitzinger, Steve Campbell, and Paul Aspinwall will be speaking in  an informal panel to math major undergraduates who are considering graduate school in math and other related subjects.  Paul Aspinwall is the graduate program director for math and physics at Duke University. 

This is an EXCELLENT opportunity for math majors to get an inside look into the application process that lies ahead.  There will be a FREE PIZZA DINNER for the attendees.  PLEASE ANNOUNCE THIS EVENT over the next week to your math major students.  Additionally, there will be a Part II to this panel in November that will allow undergrads to talk to experienced math graduate students.

This event is sponsored jointly by the SIAM Student Chapter and the Financial Mathematics Professional Science Masters Program.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7drm8lq8julqui8ncpqpgca2r4","2007-10-09 12:12:15","2007-10-09 12:37:18"
"166","1","A Survey of Plane Tilings","2007-10-24 16:00:00",NULL,"Williams 1404","Richard P. Stanley",NULL,"M.I.T.",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/gld0qvcvctrj876ahvnqjmdtf0","2007-10-12 16:38:33","2007-10-24 09:59:04"
"167","2","Cohomology of the Conformal Algebra W_2","2007-10-15 15:00:00",NULL,"HA 228","Katie Liszewski",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7nhugc1mj9gh37bedfh0qvln34","2007-10-14 22:20:44",NULL
"168","10","Large-Scale Fixed-Outline Floorplanning Design Using Convex Optimization","2007-11-27 16:30:00",NULL,"Daniels 407","Miguel F. Anjos",NULL,"University of Waterloo, Canada",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/otv50ala78aut7n7e939rg5it0","2007-10-14 22:24:44",NULL
"169","14","Departmental Tea and Cookies","2007-10-17 15:50:00",NULL,"HA 244",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hn1648813nobrtr4qbjjmr5m9s","2007-10-15 00:23:51","2007-10-15 10:11:21"
"170","3","Increasing and decreasing subsequences","2007-10-25 11:45:00",NULL,"HA 371","Richard Stanley",NULL,"MIT",,NULL,"A subsequence a_{i_1},...,a_{i_k} of a permutation a_1,a_2,...,a_n of 1,2,...,n is increasing if a_{i_1}<a_{i_2}<...<a_{i_k}. Decreasing subsequence is similarly defined. We will survey the subject of increasing and decreasing subsequences, focusing on what can be said about the longest increasing and longest decreasing subsequence of a permutation. Topics will include (a) relationship to Young tableaux and the famous RSK algorithm, (b) the asymptotic behavior of the length of the longest increasing subsequence (due to Baik, Deift, and Johansson), (c) connections with random matrix theory, and (d) an extension of the theory from permutations to complete matchings.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rpr2sf39rjvva1djku19n2e3b4","2007-10-16 12:26:24",NULL
"171","14","Departmental Tea and Cookies","2007-10-24 15:30:00",NULL,"Williams 2405",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qcg3fpnpuml8tds21imvl4vn8c","2007-10-19 15:09:08",NULL
"172","2","The Many \""Faces\"" of Toric Varieties","2007-10-22 15:00:00",NULL,"HA 228","Chirag Lakhani",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c4se73t618t5fag7nnisael9n4","2007-10-20 11:48:00",NULL
"173","8","Expressing a Fraction of Two Determinants as a Determinant","2007-12-05 15:00:00",NULL,"HA 335","Erich Kaltofen","http://www4.ncsu.edu/~kaltofen/","NCSU",,NULL,"Suppose the polynomials f and g in K[x_1,...,x_r] over the field K
are determinants of m x m and n x n matrices, respectively,
whose entries are in K or {x_1,...,x_r}.  Furthermore, suppose
h = f/g is a polynomial in K[x_1,...,x_r] and suppose that K has
at least m+1 elements.  We construct an s x s matrix C whose entries
are in K or {x_1,...,x_r}, such that h = det(C) and s = O((m+n)^6).
Our problem was motivated by resulant formulas derived from Chow forms.

Additionally, we show that divisions can be removed from formulas that
compute polynomials in the input variables over a sufficiently large
field within polynomial formula size growth.

This is joint work with Pascal Koiran at ENS Lyon, France.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jjjmadq717aks79pqf507qdpm8","2007-10-22 19:59:42",NULL
"174","4","Exponential Attractors For a Fully Hyperbolic Phase-Field System","2007-11-14 15:00:00",NULL,"HA 330","Hongjun Gao",NULL,"Nanjing Normal University and Illinois Institute of Technology","Zhilin Li",NULL,"Here we study a nonlinear hyperbolic integrodifferential system which was proposed by H. G. Rotstein et al. to describe certain peculiar phase transition phenomena. This system governs the evolution of the (relative) temperature $\\vartheta$ and the order parameter (or phase-field) $\\chi$.  We first consider an initial and boundary value problem associated with the system and we frame it in a history space setting. This is done by introducing two additional variables accounting for the histories of $\\vartheta$ and $\\chi$. In a previous joint work, Grasselli and Pata have showed that the reformulated problem generates a
dissipative dynamical system in a suitable infinite-dimensional phase space and proved the existence of a universal attractor. Here we show the existence of an exponential attractor,  by means of  recent methods due to Efendiev, Miranville, and Zelik. Thus   the  estimate of fractal dimension for exponential attractor and still the global attractor  are obtained too.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1n58f6gka0rv3qgl4arp10gc8k","2007-10-27 03:59:35","2007-11-02 02:32:32"
"175","3","Wreath product Schur functions","2007-11-02 15:00:00",NULL,"HA 335","Naihuan Jing",NULL,"NC State",,NULL,"I will present a combinatorial construction of wreath product Schur symmetric functions using colored Young tableaux (joint work with Ingram and Stitzinger). Wreath product Schur functions were introduced by Specht and later redeveloped by Macdonald to express irreducible characters of the wreath product G~S_n of a finite group G and the symmetric group S_n. Wreath products have close connections with Lie theory, for example, the orthogonal or symplectic Weyl groups are special examples of them. In the talk I will give the generalized Littlewood-Richardson rule and many other generalizations of known results for the symmetric group.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sjti71n3k4u1u4pldiuag5u6jo","2007-10-27 16:04:00","2007-10-29 23:02:58"
"176","2","An Introduction to Reductive Monoids","2007-10-29 15:00:00",NULL,"HA 228","Ryan Therkelsen",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9461088lf8gnnjhkgcfdhtnecs","2007-10-28 19:41:53",NULL
"177","14","Departmental Tea and Cookies","2007-10-31 15:50:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8uap1g2emricgcg8gjrnvml71g","2007-10-29 10:03:05",NULL
"178","7","Homopolymers: the phase transition and the limit theorems","2007-11-05 15:00:00",NULL,"HA 330","Professor Stanislav Molchanov",NULL,"University of North Carolina, Charlotte","Min Kang",NULL,"The talk will give the review of the recent activity by M.Cranston, G.Lawler, S.Molchanov and B.Vainberg on the transition of the long polymer chains from the globular to the diffusive state.  This is a new area on the borderline between the statistical mechanics and probability, containing many interesting problems. All the necessary concepts and definitions will be introduced during the lecture.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6599hmpsnfvjbhqqfh4dea50gg","2007-10-29 15:25:40","2007-11-04 22:58:37"
"179","15","Graduate Student Panel","2007-11-07 17:30:00",NULL,"HA 201","NCSU Math Grad Students",NULL,"NC State","Kelly Dickson",NULL,"Join us for a FREE SUB DINNER and Part II of our Math Grad School FAQ series geared toward undergraduates pursuing grad school.  This panel will feature current NCSU grad students in math and other related subjects.  

Get the real scoop on what grad school is all about while enjoying dinner on us (we\'ll have subs, snacks, and drinks).

This event is sponsored by NCSU\'s SIAM Student Chapter and the Financial Mathematics Professional Science Masters Program.    ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/tcln8dk20co558b71l26jd217s","2007-10-30 09:40:07",NULL
"180","15","BAKE SALE","2007-11-07 10:00:00",NULL,"Brickyard -- Bottom of Yellow Stairs","SIAM/MGSA",NULL,"NC State","Kelly Dickson",NULL,"Please show your support for NCSU\'s SIAM Student Chapter and Mathematics Graduate Student Association by stopping by our Bake Sale from 10-2 on 11/7.  

Money earned will go toward sponsoring speakers and events for the math department and math students in particular.  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jmdt3ra0hmco8h375q6i75nd40","2007-10-30 09:49:41",NULL
"181","3","A combinatorial proof of Macdonald positivity using dual equivalence graphs","2007-11-09 15:00:00",NULL,"HA 335","Sami Assaf",NULL,"University of Pennsylvania",,NULL,"Macdonald polynomials have been widely studied since they were introduced by Macdonald in 1988. Originally defined as the unique functions satisfying certain triangularity and orthogonality conditions, they are known to be symmetric and so may be expanded in terms of Schur functions. The Macdonald Positivity Conjecture (now Theorem) states the expansion into Schur functions has non-negative integer coefficients. The original proof, due to Haiman in 2001 based on joint work with Garsia,
uses difficult machinery in algebraic geometry and offers no combinatorial understanding for the coefficients. In this talk we present a purely combinatorial proof of Macdonald positivity using Haglund\'s monomial expansion for Macdonald polynomials and the newly developed theory of dual equivalence graphs, and we give a combinatorial interpretation for the
Schur coefficients.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v35vat5pd1uu8ia2b4sp8mkn78","2007-11-03 00:00:57",NULL
"182","3","Counting chains in noncrossing partition lattices","2007-11-16 15:00:00",NULL,"HA 335","Nathan Reading",NULL,"NC State University",,NULL,"Classical noncrossing partitions are set partitions which satisfy a certain \""planarity\"" condition.  Through the work of various researchers, classical noncrossing partitions were recognized as the \""type-A\"" (symmetric group) case of a general construction valid for any finite Coxeter group W.  The general definition of \""W-noncrossing partitions\"" arose from geometric group theory, where the classical noncrossing partitions give detailed information about the braid group, and W-noncrossing partitions give similar information about the Artin group associated to W.  In particular, W-noncrossing partitions lead to the definition of Eilenberg-Maclane spaces (or \""K(pi,1)\'s\"") for Artin groups.

In this talk I will provide geometric intuition for the definition of noncrossing partitions, and show how the geometric approach leads to a pleasant recursion for counting maximal chains in the lattice of noncrossing partitions.  I will assume no prior knowledge of the noncrossing partitions.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rm1iagj6960ttpn7seaq76d848","2007-11-03 00:39:25","2007-11-11 12:50:11"
"183","3","Automorphisms and derivations of polynomial and free associative algebras","2007-11-30 15:00:00",NULL,"HA 335","Vesselin Drensky",NULL,"Bulgarian Academy of Sciences",,NULL,"We present an introduction to the theory of automorphisms of the polynomial algebra C[x_1,...,x_n]. We discuss some of the main problems and survey recent results. We consider the generation of the automorphism group, tame and wild automorphisms, including the remarkable recent results of Shestakov and Umirbaev on the wildness of the Nagata automorphism of C[x,y,z]. Derivations of C[x_1,...,x_n] are related to many important problems on automorphisms and invariant theory, including the Jacobian conjecture, the 14th Hilbert problem, etc.

Although the theory of automorphisms and derivations of the free associative algebra C<x_1,...,x_n> repeats the main steps of the case of C[x_1,...,x_n], there are a lot of specific differences, due to the noncommutativity. We discuss the result of Umirbaev about the wildness of the Anick automorphism of C<x,y,z>, constructions in noncommutative algebra which lead to new automorphisms and derivations also in the commutative case, and the description of the constants of locally nilpotent derivations of C<x,y>.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qlqqaa7tkrokrid5umnqsk7gdg","2007-11-03 00:47:35","2007-11-11 12:58:51"
"184","2","Transformation Semigroups Over Groups","2007-11-05 15:00:00",NULL,"HA 228","Richard Petersen",NULL,"NC State",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/diddephb2lubv087kdc6r8ekcs","2007-11-04 21:50:38",NULL
"185","14","Departmental Tea and Cookies","2007-11-07 15:50:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/oukkr643d0nqckcnqvg5pqtqh4","2007-11-05 13:12:56",NULL
"186","10","Integrated Market Selection and Production Planning:  Complexity and Solution Approaches","2007-11-30 16:30:00",NULL,"Daniels 407","Joe Geunes",NULL,"University of Florida",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hmurc089kl46ak3gi8j9hccs2g","2007-11-06 12:33:00",NULL
"187","14","Math Comedy Night","2007-12-04 19:00:00",NULL,"Walnut Room in Talley Student Center",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kc5rkis9oibvj11h6l8o851jf0","2007-11-07 16:21:11",NULL
"188","15","Sandia National Labs FAQ","2007-11-13 16:15:00",NULL,"HA 201","Rich Lehoucq",NULL,"Sandia National Labs","Kelly Dickson",NULL,"Join us for FREE SNACKS and discussion on career and summer internship opportunities at Sandia National Labs, a US DOE laboratory with locations in New Mexico and California.  Both undergraduate and graduate math students are welcome!  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/687or9qpgose0plu48va9p38pc","2007-11-08 15:12:02",NULL
"189","14","Departmental Tea and Cookies","2007-11-13 15:50:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/edps9qigr80n2eqt4rgm44qnf4","2007-11-12 11:40:38",NULL
"190","15","SIAM Chapter Meeting","2007-11-14 15:00:00",NULL,"HA 261",,NULL,,"Kelly Dickson",NULL,"Join us for FREE SNACKS and our last meeting of the term where we will discuss plans for the spring semester.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vh5n4ilr2njn61a4u0q9deu100","2007-11-12 13:20:49",NULL
"191","4","Relaxed Matching for Stabilization of Relative Equilibria of Mechanical Systems","2007-11-29 15:00:00",NULL,"HA 330","David Long",NULL,"NCSU",,NULL,"Bloch, Leonard, and Marsden proved that under certain matching conditions a controlled mechanical system can be rewritten as an uncontrolled system for a suitable Lagrangian. This new representation leads to an interesting feedback stabilization strategy. However for many systems these matching conditions do not hold.  In this talk we discuss a technique for relaxing the matching conditions.  The theory is illustrated with the problem of stabilization of the steady-state motions of an inverted pendulum on a rotor arm.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2e4sk1val7rerm6fn078ac1j7o","2007-11-16 11:08:09","2007-11-26 18:58:27"
"192","8","On probabilistic analysis of randomization in  hybrid symbolic-numeric algorithms","2007-11-28 15:00:00",NULL,"HA 335","Zhengfeng Yang",NULL,"NCSU",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b98nbdk2pj97o15dn3t44b9lp4","2007-11-20 21:12:27","2007-11-24 18:16:59"
"193","14","PAMS Faculty Meeting","2007-11-28 16:00:00",NULL,"Cox 206",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7hbrt6fnp3rplgqotogrnepid8","2007-11-21 17:58:20","2007-11-26 15:31:56"
"194","14","Refreshments for Undergraduate Presentations","2007-11-28 15:30:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/voqniuvkd7m9ka7ppar100kq3s","2007-11-21 19:00:41","2007-11-26 15:31:13"
"195","14","Departmental Tea and Cookies","2007-11-29 15:50:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9i0umdag27hndd2nqgnbuonq00","2007-11-21 19:01:43",NULL
"196","14","Undergraduate Research Presentations","2007-11-28 14:30:00",NULL,"HA 330","Ralph Abbey, Jacob Frelinger, and  Eric Lownes",NULL,"NC State",,NULL,"Ralph Abbey: \\\"" Computational Data Clustering and Mining\\\"". Abstract: As the ease of collecting large amounts of data increases, the ability to distil useful information out of these large datasets becomes significantly more important. The research investigated current clustering algorithms and experimented with modifications on those algorithms, as well as a look into new approaches. These algorithms were then tested on benchmark document sets. In many cases, the adaptations to pre-existing algorithms performed better than the basic algorithm.
----------------------------------------------------
Jacob Frelinger:  \\\""Homing endonuclase genes effects on Hardy-Weinberg: models to combat dengue fever transmission in A. aegytpi\\\"".  Abstract: Homing endonuclease genes offer an option in controlling dengue fever transmission in A. aegytpi, as well as controlling other diseases in other hosts, or controlling pest populations.  By understanding the effects of homing endonuclease genes on Hardy-Weinberg, methods to control pest populations and hence the infectious diseases they carry become apparent. Several potential situations are modeled in software at the population gene level and results analyzed.
-----------------------------------------------------
Eric Lownes: \\\""The Heat Kernel of Homesick Random Walks on K-Regular Trees\\\"". Abstract: Certain types of homesick random walks were introduced by Lyons to estimate the growth of groups.  For such a random walk on a k-regular tree, we compute its Laplacian and its heat kernel.  Our methods are 
based on the use of combinatorial coverings as introduced by Chung and Yau.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/msnko2ikcbavre2deckpb5qk84","2007-11-25 14:41:58","2007-11-25 14:42:49"
"197","14","Undergraduate Research Presentations","2007-12-05 14:30:00",NULL,"HA 330","Justin Fowler, Nicole Kroeger, and Dhrumil Patel",NULL,"NC State",,NULL,"Justin Fowler: \""Combinatorics on Partial Word Correlations\""
Abstract: There has been a fair amount of study surrounding both the period and weak period sets of partial words over a finite alphabet, and specific representations of them called correlations, which are binary and ternary vectors indicating the periods and weak periods. This research continues the study of combinatorics on partial word correlations. In particular, we investigate the population size of correlations, that is, the number of partial words sharing a given correlation, and obtain algorithms to compute it.
----------------------------------------------------
Nicole Kroeger:  \""Hadamard Difference Sets in Groups of Order 144 \""
Abstract:  Finding difference sets and classifying existence of them is  a major project of combinatorics.   We present the results of our investigation in (144,66,30) difference  sets and explain a new construction technique which produced difference sets in 37 groups.  
-----------------------------------------------------
Dhrumil Patel : \""Financial Models in Continuous and Discrete Time\""
Abstract: The problem of pricing a European call option is considered in both a discrete and continuous-time setting. To this end, we consider  the binomial asset pricing model in discrete-time and a stock price modeled  by geometric Brownian motion in continuous time. The latter model leads to the well-known Black-Scholes option pricing formula. The option pricing problem is discussed in connection with the notion of arbitrage and risk-neutral pricing.  We consider both constant and stochastic interest rates  and comparisons are made between the discrete and continuous-time models.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ag8adpa8hl85mgo38piu9h57p4","2007-11-25 14:48:32","2007-12-03 17:02:29"
"198","14","PAMS Faculty Meeting Refreshments","2007-11-28 15:30:00",NULL,"Dabney Second floor Balcony",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7g7iejaerc21idehjgf8eq9np8","2007-11-26 15:35:35",NULL
"199","14","Undergraduate Presentation / Departmental Tea and Cookies","2007-12-05 15:30:00",NULL,"HA 245",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/efrmjj1bdrkpa411d6t46tjp34","2007-12-03 17:00:18",NULL
"200","4","Cable knot solutions of the vortex filament flow","2008-02-13 15:00:00",NULL,"HA 330","Thomas Ivey","http://www.cofc.edu/~iveyt/","College of Charleston",,,"A naive model of vortex filament motion in an ideal fluid leads to an integrable nonlinear evolution equation, known as the localized induction approximation or vortex filament flow (VFF), closely related to the cubic focussing nonlinear Schroedinger  (NLS) equation.  In particular, spatially closed filaments may be constructed from solutions the AKNS scattering system for certain periodic NLS potentials, characterized in terms of their Floquet spectra. In this talk, I will discuss joint work with Annalisa Calini, describing how to generate a family of closed VFF solutions of increasing topological complexity via a sequence of deformations of the Floquet spectrum of the multiply-covered circle.  We prove that every step in this sequence corresponds to constructing a cable on previous filament; moreover, the cable\\\'s knot type (which is invariant under the evolution) can be read off from data generating the deformation sequence.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vgllhucr2jshgt2cqs5tegsiuo","2007-12-04 21:34:26","2008-02-04 11:05:50"
"201","8","Breaking the Akiyama-Goto Algebraic Surface Public-key Cryptosystem and a Short Introduction to Multivariate Analytic Factorization","2008-05-07 15:00:00",NULL,"HA 335","Prof. Maki Iwami",,"Osaka University of Economics and Law, Japan","Erich Kaltofen",,"I had suggested algorithms for multivariate analytic factorization
which is a factorizaion over  ring of formal power series, fixing an
expansion point. And in recent years, I have studied application
possibilities for cryptosystems.
I\'ll talk about my recent works about breaking the Akiyama-Goto
algebraic surface pulic-key cryptosystem (ASC) whose security is
related to a problem of finding sections on fibered algebraic
surfaces.
The original ASC was proposed in 2004.
There is Uchiyama-Tokunaga attack using reductions for some special
cases on January 2007, and I generalized it to all the cases by
extending it to be able to perform in the polynomial ring over
rational function field on July 2007, and also perform in the
polynomial ring over $F_p$ using Groebner bases techniques on November
2007. There is also Inanov & Voloch trace map attack. I also propose
breaking the improved ASC proposed on January 2008. Therefore we need
a significant improvement to be a secure one, and I explain it from
the viewpoint of symbolic computation.

Note: Fresh Japanese sweets will be available at the seminar.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m3u4c4p3l947vabfvki6hn90r4","2007-12-19 12:41:07","2008-05-05 20:01:07"
"202","8","Advances in Algorithms for Symbolic Polynomials","2008-03-19 15:00:00",NULL,"HA 335","Stephen M. Watt","http://www.csd.uwo.ca/~watt/","University of Western Ontario","Michael Singer",,"We wish to work with polynomials where the exponents are not known in advance,
such as $x^{2n} - 1$.  There are various operations we will want to be able
to do, such as squaring the value to get $x^{4n}-2x^{2n}+1$, or differentiating
it to get $2nx^{2n-1}$.  Expressions of this sort arise frequently in practice,
for example in the analysis of algorithms, and it is difficult to work with
them effectively with current computer algebra software.

We consider the case where multivariate polynomials can have exponents that are
themselves integer-valued multivariate polynomials. and we present algorithms
to compute their GCD and factorization.  The algorithms fall into two families:
algebraic extension methods and interpolation methods.  The first family of
algorithms uses the algebraic independence of  $x$, $x^n$, $x^{n^2}$, $x^{nm}$,
etc, to solve related problems with more indeterminates.  Some subtlety is
needed to treat fixed divisors of the exponent polynomials.  We present a
recent result showing how to treat fixed divisors while preserving sparsity.
The second family of algorithms uses evaluation and interpolation of the
exponent polynomials.  Additionally, we also explore the case of symbolic
exponents on rational coefficients (e.g. $4^{n^2+n}-81$) and show how to avoid
integer factorization.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qn90486jd7dgjk4sal2eltfri4","2007-12-20 18:12:59","2008-03-17 12:26:52"
"204","8","Point counting in genus 2: towards 128 bits","2008-03-26 15:00:00",NULL,"HA 335","Eric Schost","http://www.csd.uwo.ca/~eschost/","University of Western Ontario","Erich Kaltofen",,"Recent work on the efficiency of group operations shows that genus 2 cryptosystems can be competitive with, or faster than, their elliptic analogues, for a similar level of security. One of the last missing steps is the determination of a suitable secure curve over a prime field of size about 2^128.

I will describe ongoing work with Pierrick Gaudry towards this goal, and review some of the underlying algorithms, from factorization in high degree extensions to lifting techniques for triangular sets.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p5bv0rkdjl2j1tmb6a7srt5uo0","2007-12-21 05:04:05","2008-03-24 11:31:21"
"205","3","Picard-Lefschetz periods and integrable hierarchies","2008-01-11 16:00:00",NULL,"HA 335","Todor Milanov",NULL,"Stanford University",,NULL,"If X is a projective manifold with sufficiently many rational curves then there is an algebraic formalism that allows us to reconstruct the higher genus Gromov-Witten (shortly GW) invariants of X in terms of the genus-0 ones and the higher genus GW invariants of a point. It is still an open problem to determine whether the Gromov-Witten invariants of such manifolds X are governed by integrable hierarchies. So far it is known that the GW theory of a point is governed by the KdV hierarchy and the GW theory of the projective line by a certain extension of the 1-Toda lattice hierarchy. 
 
On the other hand the algebraic formalism in GW theory makes sense in singularity theory, i.e., the study of isolated critical points of holomorphic functions. So we may define the analogue of GW invariants and ask the same question, is it true that they are governed by integrable hierarchies. In a joint work with A. Givental we showed that the answer is positive in the case of singularities of type A, D, or E. In this talk I would like to give an introduction to this subject and to advertise an approach to integrable systems based on vertex operators, Hirota quadratic (also known as bi-linear) equations, and Picard-Lefschetz periods. No previous knowledge of Gromov-Witten or singularity theories will be assumed.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5kipg7lo2ibfiunhdg0jqs8on8","2008-01-08 21:39:34",NULL
"206","4","Pressureless Euler/Euler-Poisson systems in the Wasserstein space","2008-01-18 15:00:00",NULL,"HA 330","Adrian Tudorascu",NULL,"Georgia Institute of Technology",,NULL,"We shall present recent results on the existence, uniqueness  
and regularity of action-minimizing solutions to the pressureless Euler-Poisson system with uniform background charge in spatial dimension one. Also, we shall discuss the existence of \""sticky particles\"" solutions to the initial-value problem for 1-d pressureless Euler/Euler-Poisson systems. As conjectured by various authors (E, Rykov, and Sinai; Brenier and Grenier), the solution to pressureless Euler satisfies the Oleinik entropy condition. Central to our approach is a flow-map formula relating the velocity of an  absolutely continuous curve in the Wasserstein space (of probability measures) to the family of optimal maps that rearrange a given reference probability into the measures on the curve. Joint work with: W. Gangbo and T. Nguyen.

Faculty, students and post-docs are encouraged to attend.

Dr. Tudorascu is a candidate for an assistant professorship in the mathematics department.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bidssspqnbaalh3vevalhpjpq0","2008-01-14 21:42:54",NULL
"207","4","Mathematical modeling of interactions between cells in the brain","2008-03-26 15:00:00",NULL,"HA 330","Anne Catlla","http://fds.duke.edu/db/aas/math/acatlla","Duke University",,,"Our brains are composed of networks of cells, including neurons and glial cells. While the significance of neurons has been established by biologists, the role of glial cells is less understood.  One hypothesis is that glial cells facilitate neural communication in nearby neurons, while suppressing communication among more distant neurons via a reaction-diffusion process. I consider this proposed mechanism using
partial and ordinary differential equation models. By analyzing the ordinary differential equation model, I can determine a condition for this hypothesis to hold. I then compare the results of this analysis with simulations of the partial differential equation model and discuss the biological implications.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bgot17c6q1af7qv23pqni7benk","2008-01-14 21:54:41","2008-03-18 00:34:57"
"208","4","Strichartz estimates for wave equations on Schwarzschild black hole","2008-04-09 15:00:00",NULL,"HA 330","Jason Metcalfe",,"UNC Chapel Hill",,,"This is a joint work with J. Marzuola, D. Tataru, and M. Tohaneanu.  We prove Strichartz estimates for wave equations on Schwarzschild black hole backgrounds.  This is done by combining some local energy estimates with a global-in-time outgoing parametrix for
small perturbations of the d\'Alembertian.  Particular care needs to be taken near the regions of trapping, namely the event horizon and the photon sphere.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v640vhh39gfj2vtme8g6p2qq68","2008-01-14 21:58:42","2008-04-04 15:44:31"
"209","6","Stochastic Immersed Boundary Methods for Simulation of Microscopic Fluid Structure Systems with Thermal Fluctuations","2008-02-28 15:00:00",NULL,"HA 335","Paul Atzberger","http://math.ucsb.edu/~atzberg/","UC-Santa Barbara","Mansoor Haider","http://www.math.ncsu.edu/math/Announcements/NAS/SPRING_2008/atzberger.html","The immersed boundary method is a numerical approach which has been applied to many macroscopic systems involving a fluid which interacts with flexible elastic structures. For microscopic systems of sufficiently small length scale thermal fluctuations become significant and also must be taken into account. In this talk we shall discuss an extension of the immersed boundary method framework which incorporates thermal fluctuations through appropriate stochastic forcing terms in the fluid equations. This gives a system of stiff SPDE\\\\\\\'s for which standard numerical methods perform poorly. We shall discuss a few different approaches by which stochastic calculus can be used to obtain analytic results to help in handling the stiff features of the equations. We will further show how this can be used to formulate numerical methods for the fluid-structure equations both discretized on uniform and multilevel adaptive meshes. To demonstrate the approaches in practice we shall present simulation results the microscopic mechanics of polymers, polymer knots, membrane sheets, and vesicles. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l0p0ipufgla4dkhfq5vhlpanvg","2008-01-17 13:37:56","2008-02-25 00:28:21"
"210","2","An Active Set Algorithm for Box Constrained Optimization","2008-01-23 15:00:00",NULL,"HA 330","Hongchao Zhang","http://www.ima.umn.edu/~hozhang/","IMA, University of Minnesota",,NULL,"This talk focuses on large-scale optimization algorithms for box constraint optimization. Such problems arise in various fields including optimal control, variational inequalities, multiplier methods as well as in many real applications. In this talk, an overview of recent developments on both theoretical and computational results in this field is given. In particular, a new active set algorithm (ASA) with strong local and global convergence properties is introduced. In addition, a brief review of the nonlinear conjugate gradient methods is also included. An
implementation of ASA based on the recent conjugate gradient algorithm CG_DESCENT and a cyclic Barzilai-Borwein algorithm is given. Numerical experiments are presented using box constrained problems in the CUTEr and MINPACK-2 test problem libraries.

Refreshments at 2:30 pm in HA 243.

Dr. Zhang is a candidate for the General Math position.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d3vljebvo9catth1ldt0srlfl0","2008-01-17 20:43:46","2008-01-23 13:03:42"
"211","3","Algebraic Statistics","2008-01-25 16:00:00",NULL,"HA 335","Seth Sullivant",NULL,"Harvard University",,NULL,"Algebraic statistics advocates algebraic geometry as a useful language for discussing statistical and probabilistic problems. The starting point is the observation that many statistical models are described by algebraic constraints or parametrizations. I will try to illustrate this connection with some examples including Gaussian conditional independence models, log-linear models, and phylogenetic models.

Departmental tea at 3:30 pm in HA 243.

Dr. Sullivant is a candidate for an assistant professorship in the Mathematics Department.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mnlgkbp1b5ceibflnoj59h2upo","2008-01-19 17:14:32",NULL
"212","2","New mathematical models for understanding physiological and ecological systems","2008-01-22 15:00:00",NULL,"HA 330","Van Savage",NULL,"Harvard Medical School",,NULL,"It has long been known that metabolic rate, heart rate, and lifespan scale in a systematic and inter-related way with body size and temperature. These scaling relationships hold over an astronomical range in body size (~21 orders of magnitude) and across taxonomically diverse organisms that live in a myriad of environments. Moreover, these relationships for body mass are usually well approximated by power laws with exponents that are simple multiples of 1/4, and for body temperature by exponential Boltzmann-Arrhenius factors. I will describe a model to explain these relationships that focuses on the cardiovascular system and the kinetics of biochemical reactions. I will also discuss how finite-size corrections and asymmetric branching can refine the original model’s predictions. I will then present my work that shows how these scaling relationships can be used to examine critical physiological and ecological processes. At the physiological level, I will discuss models to explore, for example, tumor growth dynamics, cell size, and why an elephant sleeps much less than a mouse. At the ecological level, I will outline a trait-based framework to investigate the effects of fluctuating environments on ecosystems and the effects of temperature on predator-prey interactions. Together, these have the potential to gauge the impact of climate change on ecosystem dynamics and stability.

Van Savage is a math candidate. An online version of his CV can be found at: http://fontana.med.harvard.edu/www/Documents/VanSavage/Van%20Savage/cv.htm
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/todev5sqeu65ccgbpjni1jt4gc","2008-01-20 16:53:53","2008-01-20 17:05:00"
"213","14","Departmental Tea and Cookies","2008-01-22 14:30:00",NULL,"HA 243",,NULL,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3j4p4rrm6ucgfajkmtm1qraod8","2008-01-20 16:55:03",NULL
"214","9","Motor proteins, dolphins, and Winnetou - or - How irregular motion can sometimes be the fastest and most efficient","2008-01-22 16:30:00",NULL,"Fox 306","Martin Bier",NULL,"East Carolina University",,NULL,"The motor protein kinesin literally walks on two legs along the
biopolymer microtubule as it hydrolyzes ATP for its fuel supply.  The number of accidental backsteps that kinesin takes appears to be much larger than what one would expect given the amount of free energy that ATP hydrolysis makes available.  This is puzzling as more than a billion years of natural selection should have optimized the motor protein for its speed and efficiency. 

I will point out how the stepping kinesin is a realization of
Bennett\\\'s well-known information-driven heat engine operating in reverse and I will analyze the production and destruction of Shannon entropy.  More backstepping allows for the production of more entropy.  The production of entropy will make free energy available.  With that free energy, the catalytic cycle of the kinesin can be speeded up.  I will show how the actually measured backstepping rate represents an optimum at which maximal net forward speed is achieved. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2qcnol36m5a0qmv47iio81t2ko","2008-01-22 00:19:57","2008-01-22 10:58:02"
"215","9","Modeling blood lipoprotein metabolism:  Understanding mechanisms behind good and bad cholesterol","2008-01-29 16:30:00",NULL,"Fox 306","Laura Potter",,"Glaxo Smith Kline",,"http://www.ncsu.edu/biomath/abstracts/PotterSpring08.txt","Blood levels of \\\""good\\\"" and \\\""bad\\\"" cholesterol are strong predictors of risk
for coronary artery disease and heart attack.  These levels are tightly
regulated as part of a complex system of lipoprotein metabolism.
Understanding these regulatory pathways and the effects of drug
interventions is critical for the development of new lipid-altering
therapies.  We are developing a mathematical model for blood lipoprotein
metabolism that incorporates the dynamics of lipoprotein particles and
their lipid components, including cholesterol and triglycerides. This
presentation will highlight the biology and mathematics behind the model.
I will also discuss our model calibration framework, which involves fitting
multiple sets of experimental data simultaneously. Finally, example 
applications of the model will be presented.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nhl7r5g1tuksigc7qjhmqrss8g","2008-01-22 00:21:00","2008-01-28 15:46:12"
"216","9","Leverage: an ecological economic factor to optimally prioritizing conservation funding","2008-02-12 16:30:00",NULL,"Fox 306","Brett Matzuk",,"NC State",,"http://www.ncsu.edu/biomath/abstracts/BrettSp08.txt","The rate at which habitat is being destroyed is alarming, and current conservational actions are inadequate to prevent this decline. At the heart of this global issue is how to distribute limited resources amongst identified priority regions for biodiversity conservation. Due to the recent focus on the immediate need for conservation in these priority regions, international organizations have been able to construct strategies for raising funds through the championing of dierent
priorities. These campaigns have helped empower people to feel they make a difference and have helped to reestablish the connection between the environment and society. This concept of people seeing their contributions making a difference leads to an important feedback in economic processes central to prioritizing funding, known as leverage. Leverage is the ability of a region to generate more funding if money is allocated to that region; it is very important to the problem of allocating funding  among multiple priority regions. We propose a simple dynamic cost-benefit model for optimally allocating resources among priority regions which incorporates leverage, with the objective of maximising the number of species conserved. Using optimal control theory, we formulate a optimal spending strategy to meet our objective. We use this to evaluate current allocation 
to multiple priority regions in the face of diering economic, ecological, and environmental factors. We find that with the incorporation of leverage, current international allocation strategies are not over spending in economically rich countries such as the US, but are very similar to our optimal allocation strategy.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kepq91hj3g23s7cgabn8glumjk","2008-01-22 00:22:18","2008-02-09 15:18:00"
"217","10","A Model for the Adaptive Preventive Maintenance System in a Multi-skilled Workforce Environment","2008-01-29 16:30:00",NULL,"Daniels 401","Bahram Alidaee","http://faculty.bus.olemiss.edu/balidaee/","University of Mississippi",,"http://www.or.ncsu.edu/documents/ORSeminar-Jan292008-Alidaee.pdf","Manufacturing and service flexibility can be a major competitive advantage in firms as well as well designed supply chains. One way to address such flexibility is through workforce agility that can be created via cross-training. This talk is concern with crosstraining of workforce. We will present a new integer programming (IP) formulation of the problem. The presented model is a generalization of multiple resource generalized
assignment problem (GMRGAP). The IP formulation can be applied in a variety of settings where a subset from a larger set is to be selected for assignments, in that, if an object is selected for assignment then several related objects also must be selected for assignments. Graph theoretic formulation of special cases will be presented. Extension of the formulations to variety of settings including preventive management, unmanned aerial
vehicles, target assignment problem, multiple vehicle routing, multiple project management, and optimal redundancy allocation for information technology disaster recovery will be presented. Extension and a two-stage model for policy analysis in development of multi-skilled human resources will be presented. Finally, computational experiment using CPLEX and heuristics will be presented. Refreshments will be served in 401 Daniels Hall at 4:00 pm",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/modoe4id014gqt0ap6ta73kpl0","2008-01-22 00:26:25","2008-01-28 15:51:24"
"218","10","Steady-State Simulation Analysis Using ASAP3","2008-01-18 16:30:00",NULL,"Daniels 401","James R. Wilson",NULL,"NCSU",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nccjf95hdj13ns7lavgahi5bs8","2008-01-22 00:29:02",NULL
"220","3","Regular cell complexes in total positivity","2008-03-14 16:00:00",NULL,"HA 335","Patricia Hersh","http://www.math.indiana.edu/people/profile.phtml?id=phersh","Indiana University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/algsem031408.pdf","We give a new criterion for determining whether a finite CW complex is regular. This involves both combinatorial conditions on the closure poset and also topological conditions on the codimension one cell incidences. We will also discuss how this applies to a conjecture of Fomin and Shapiro that certain stratified totally non-negative spaces with the Bruhat intervals as their closure posets are regular CW complexes.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ptodlp1jtrof8r42c0dllf6o78","2008-01-25 09:10:52","2008-03-09 10:36:58"
"221","3","Categories of weight modules of Lie algebras","2008-04-18 16:00:00",NULL,"HA 335","Dimitar Grantcharov","http://www.math.sjsu.edu/~grantcharov","San Jose State University",,,"In the early 20th century H. Weyl classified all finite-dimensional representations of the classical Lie algebras in terms of the so-called character formula. Following works of G. Benkart, D. Britten, S. Fernando, V. Futorny, F. Lemire, A. Joseph and others, in 2000, O. Mathieu achieved a major breakthrough in the representation theory by obtaining an infinite dimensional analog of Weyl\'s result for the so called weight modules. In this talk we will discuss the recent developments of Mathieu\'s ideas and methods. More precisely, results related to the structure of the indecomposable weight modules will be presented. These results are a part of an ongoing joint project with V. Serganova.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2abbl95na6duiak25bksvurehs","2008-01-25 09:12:32","2008-04-11 14:22:06"
"222","4","Not-so-Continuum Behaviors in Granular Material","2008-04-16 15:30:00",NULL,"HA 330","Karen Daniels","http://www.physics.ncsu.edu/people/faculty_daniels.html","NC State",,,"From bowls of nuts to eroding soil, granular materials are all around us. While for many years they have been modelled using continuum equations, some of their properties and dynamics challenge this approach. In this talk, I will both introduce some characteristic features of granular materials (such as force chains) and describe recent results from several experiments in progress in my lab in the Physics Department: granular acoustics, size-segregation, and fault-like failure.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u1ldiqkdd9e91rp3a67t2unj9o","2008-01-25 23:08:21","2008-04-11 12:13:23"
"223","9","Exploration, innovation, and selective sweeps in the ecology and evolution of influenza","2008-03-18 16:30:00",NULL,"Fox 306","Katia Koelle","http://fds.duke.edu/db/aas/Biology/faculty/katia.koelle","Duke University",,"http://www.ncsu.edu/biomath/abstracts/Koelle08.txt","For many biological systems, the timescale at which ecological interactions occur is much shorter than the timescale at which evolutionary changes occur. For rapidly evolving pathogens such as influenza, however, this is not the case; influenza researchers therefore need to understand both the ecological interactions between the host and the pathogen and the virus~Rs evolutionary changes in order to ultimately control the disease in humans. Recently, a study looking at the evolutionary patterns of influenza showed that, while the virus~Rs genetic evolution occurred gradually, its antigenic evolution occurred in a punctuated manner. (Genetic evolution refers to how the virus~Rs nucleotides change over time; antigenic evolution refers to how the virus changes over time with respect to how our immune system recognizes it.) Previous research from our group hypothesized that these differences in evolutionary patterns could be explained by the presence of \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\""neutral networks\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"" in the virus~Rs genotype space: networks of sequences that differ genetically from one another but fold into the same protein conformation and thereby share antigenic
properties. Here, I will present a simple epidemiological model that implicitly incorporates these neutral networks. I show that this model can reproduce (1) the seasonal and interannual outbreak patterns of influenza, (2) the quantitative patterns of influenza~Rs antigenic evolution, and (3) the patterns of the virus~Rs genetic evolution, including its characteristic phylogenetic tree. I end with how this model may be useful in understanding patterns of viral diversity in other host species (e.g., avian and equine hosts), and how this understanding could be used in the design of control strategies for pandemic influenza.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/emv1dcpc5hgj33pbi50hcb1qf0","2008-01-28 10:54:12","2008-03-17 11:43:25"
"224","10","Building a Nationwide Health Information Network","2008-02-05 16:30:00",NULL,"Daniels 401","Houtan Aghili",," IBM Healthcare and Life Sciences",,"http://www.or.ncsu.edu/documents/ORSeminar-Feb5-Aghili.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/97vlc8b08u9s73mbstr9vqdtqk","2008-01-28 11:58:44",NULL
"225","6","Numerical Methods for Chemotaxis and Haptotaxis Models","2008-03-25 15:00:00",NULL,"HA 330","Alexander Kurganov","http://www.math.tulane.edu/~kurganov/","Tulane University","Alina Chertock",,"I will present new finite-volume and finite-element methods for a class of chemotaxis models and for a closely related haptotaxis model. In its simplest form, the chemotaxis model is described by a system of nonlinear PDEs: a convection-diffusion equation for the cell density coupled with a reaction-diffusion equation for the
chemoattractant concentration. It is well-known that solutions of such systems may develop spiky structures or even blow up in finite time provided the total number of cells exceeds a certain threshold. This makes development of numerical methods for chemotaxis systems an extremely delicate and challenging task.

The first step in the derivation of the finite-volume method is made by adding an equation for the chemoattractant concentration gradient to the original system. The convective part of the resulting system is then  of a mixed hyperbolic-elliptic type and therefore straightforward numerical methods for the studied system may be unstable. We design a second-order central-upwind scheme for the extended system of PDEs. The scheme is positivity preserving, which is a very important stability property of the method.

In order to derive a finite-element method -- the interior penalty discontinuous Galerkin method -- the chemotaxis system is reformulated in the form of a convection-diffusion-reaction system with a hyperbolic convective part. This form is suitable for designing discontinuous Galerkin methods. We consider Cartesian grids and prove error estimates for the proposed high-order discontinuous Galerkin methods. Our proof is valid for pre-blow-up times since we assume boundedness of the exact solution.

Both methods are applied to a number of two-dimensional problems including the most commonly used Keller-Segel chemotaxis model and its modern extensions as well as to a haptotaxis system modeling tumor invasion into surrounding healthy tissue.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sehd5roctm0ne3k36jkt2n7aq8","2008-01-28 12:25:51","2008-03-24 11:30:49"
"226","4","Dispersive Shock Waves and Their Interactions","2008-02-01 15:00:00",NULL,"HA 330","Mark Hoefer","http://amath.colorado.edu/student/hoefer/","National Institute of Standards and Technology , Boulder, Colorado",,,"Thunder, the crack of a whip, and the boom heard from a jet plane surpassing the speed of sound are familiar occurrences in human experience and all result from the generation of \""classical\"" shock waves.  This talk will focus on a very different type of shock wave that propagates through dispersive media such as the superfluidic Bose-Einstein condensate (BEC) and defocusing, nonlinear photonic crystals.  These shock waves cannot be heard but have been observed in recent experiments and represent a relatively new and exciting area of physical and applied mathematical research.  In contrast to the well known theory of classical shock waves in a compressible fluid where dissipation plays the dominant role in regularizing the shock solution and a strong limit exists, the propagation of a dispersive shock wave (DSW) through a dispersive fluid requires a dispersive regularization where only a weak limit exists.  Whitham averaging theory will be used to study dispersive shock waves in the context of the Nonlinear Schrodinger equation.  Applications to physically relevant problems including recent BEC blast wave experiments, DSW interactions, and the piston shock wave problem will be discussed.

Faculty, students and post-docs are encouraged to attend.

Dr. Hoefer is a candidate for an assistant professorship in the mathematics department.

Tea will be served at 2:30pm before the seminar, in HA 243.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/72dbp27sksqjedc5reg3b7kes8","2008-01-29 11:34:02",NULL
"228","2","A Dimension-Adaptive Sparse Grid Stochastic Collocation Technique for Partial Differential Equations with High-Dimensional Random Input Data","2008-02-01 16:00:00",NULL,"HA 330","Clayton Webster"," http://people.scs.fsu.edu/~webster/Welcome.html","Sandia National Labs",,NULL,"This talk will propose and analyze a dimension-adaptive (anisotropic) sparse grid stochastic 
collocation method for solving partial differential equations with random coefficients and forcing 
terms (input data of the model). These methods have proven to have dramatic impact on several 
application areas, including statistical mechanics, financial mathematics, bioinformatics, and other 
fields that must properly predict certain model behaviors. The method consists of a Galerkin 
approximation in the space variables and a collocation, in probability space, on anisotropic sparse 
tensor product grids utilizing either Clenshaw-Curtis or Gaussian knots. Even in the presence of 
nonlinearities, the collocation approach leads to the solution of uncoupled deterministic problems, 
just as in sampling-based methods, such as Monte Carlo. This talk includes both a priori and a 
posteriori approaches to adapt the anisotropy of the sparse grids to each given problem. 
This talk will also provide a rigorous convergence analysis of the fully discrete problem and 
demonstrate strong error estimates for the solution using Lq norms. In particular, our analysis 
reveals at least an algebraic convergence with respect to the total number of collocation points. 
The derived estimates are then used to compare the efficiency of the method with other ensemble- 
based methods. Numerical examples illustrate the theoretical results and are used to compare this 
approach with several others, including the standard Monte Carlo. In particular, for moderately 
large dimensional problems, the sparse grid approach with a properly chosen anisotropy is very 
efficient and superior to all examined methods. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/njl957krot410h8gsd4i6g9bls","0000-00-00 00:00:00",NULL
"229","3","Sortable elements - beyond finite type","2008-02-29 16:00:00",NULL,"HA 335","David Speyer","http://www-math.mit.edu/~speyer/","MIT",,,"In a finite Coxeter group W, Nathan Reading introduced \""sortable elements\"" in order to relate two of the objects enumerated by W-Catalan numbers - the variables in the W-cluster algebra and the noncrossing partitions for W. Research started by Nathan Reading, and completed by he and I, gives very precise and simple connections between sortable elements, cluster algebras, non-crossing partitions and semi-invariants of quiver representations. More recently, we have found analogues of our results that hold for all Coxeter groups, not only the finite ones. I will explain this work, and describe some of the intriguing new phenomena which appear when we leave the finite case. I will not assume any knowledge of clusters, non-crossing partitions or quivers and I will try to assume only a vague familiarity with Coxeter groups.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u8ou9ljjm424mandbsuuvgerio","2008-02-01 16:19:38","2008-02-16 14:27:19"
"230","9","Quantifying the factors that control biodiversity","2008-02-19 16:30:00",NULL,"Fox 306","Jim Clark","http://fds.duke.edu/db/aas/Biology/faculty/jimclark","Duke University",,"http://www.ncsu.edu/biomath/abstracts/ClarkSpr08.txt","Estimates of demographic relationships are needed to evaluate allocation tradeoffs and how
species differences contribute to biodiversity. To quantify variation within individuals,
among individuals, and among species and its contribution to life history tradeoffs,
demographic heterogeneity, and biodiversity, we constructed models of interacting life
history schedules and fitted them to long-term experimental and monitoring data on tree
population dynamics.  Spatio-temporal data include increment cores, seed traps, canopy and
reproductive status, remote sensing of canopy architecture, light, soil moisture, and
tree, seedling, and sapling censuses.  Data derive from mapped plots with superimposed
treatments that include herbivore exclosures, gap creation, and CO2 fumigation, all
applied as intervention designs over multiple years.  A hierarchical model is used to
estimate the interactions among life history traits and to predict life history schedules
for all dominant canopy species in nine stands from the Piedmont Plateau and southern
Appalachians of North Carolina that include a range of soils, hydrologic conditions, and
elevations.  Covariates are included with random effects taking up additional variation at
individual, plot, or stand level. We find large differences among species in many traits
that only become apparent from estimates of latent variables, which can be represented as
predictive distributions.  Although many species appear to have similar demographic rates
when considered along only a few resource or environmental axes, underlying interactions
differ substantially.  Species differ further in terms of the extent to which life history
schedules interact over time.  While some species show clear year-to-year correlations in
growth and fecundity, others do not.   Given the high dimensionality of species
differences, data showing no differences among species is best taken as `no evidence\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\',
rather than `evidence against\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\' niche differences.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fhp6su01ac7dt3kerbj17srd90","2008-02-04 10:34:40","2008-02-18 13:00:32"
"231","9","Smart Materials in Biomedical Applications","2008-04-08 16:30:00",NULL,"Fox 306","Stefan Seelecke","http://www.bme.ncsu.edu/directory/bio.php?userid=sseelec&Group=&Images=Yes","NC State",,"http://www.ncsu.edu/biomath/abstracts/SeeleckeSpri08.txt",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/est2lpqjsb847a4t1kaqp64rb0","2008-02-04 10:36:17","2008-04-08 13:53:45"
"232","9","The Role of Statistical Principles in Quantitative Biomedical Modeling","2008-04-22 16:30:00",NULL,"Fox 306","Marie Davidian","http://www4.stat.ncsu.edu/~davidian/","NC State",,"http://www.ncsu.edu/biomath/abstracts/DavidianSpr08.txt",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mjjmeij6eh6bjl33iqjgb1b4no","2008-02-04 10:37:33","2008-03-24 11:19:34"
"233","9","Modeling intracellular signaling pathways","2008-04-01 16:30:00",NULL,"Fox 306","Tim Elston","http://www.med.unc.edu/pharm/faculty/elston.htm","UNC-Chapel Hill",,"http://www.ncsu.edu/biomath/abstracts/ElstonSpr08.txt",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lo26jshc53ljhnul0o3udh7tpo","2008-02-04 10:38:52","2008-04-01 09:22:00"
"234","9","Resource based theory of the ecology of mutualism and the mycorrhizal symbiosis","2008-04-15 16:30:00",NULL,"Fox 306","James Umbanhowar",,"UNC-Chapel Hill",,"http://www.ncsu.edu/biomath/abstracts/UmbanhowarSpr08.txt",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/194pv2qq2bnnv3ri86tqna0q58","2008-02-04 10:40:17","2008-04-14 12:40:13"
"235","10","A Parallel Macro Partitioning Framework for Mixed Integer Programming","2008-02-12 16:30:00",NULL,"Daniels 218","Andrew Miller",,"University of Wisconsin - Madison",,"http://www.or.ncsu.edu/documents/ORSeminarFeb122008-Dr.Miller.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vb08ubjbtc1uksk62tpldentk8","2008-02-04 11:25:51","2008-02-11 11:03:37"
"236","10","Algorithms for Computing Nash Equilibria of Large Sequential Games","2008-02-26 16:30:00",NULL,"Daniels 218","Javier Pena","http://www.math.cmu.edu/~ccf/docs/Faculty/pena.htm","Carnegie Mellon University",,"http://www.or.ncsu.edu/documents/ORSeminarFeb262008-Pena.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e16pqks1vg4kqrp2ghc0brinkg","2008-02-04 11:28:09","2008-02-25 00:27:36"
"237","10","Music Science and the Mathematical Modeling of Tonality","2008-03-25 16:30:00",NULL,"Daniels 218","Elaine Chew","http://www-rcf.usc.edu/~echew/","Harvard University",,"http://www.or.ncsu.edu/documents/Dr.ElaineChewMar252008.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fmovd79u1dkgtuklm8r9ld2nt4","2008-02-04 11:30:41","2008-03-24 11:14:35"
"238","14","Departmental Tea and Cookies","2008-02-05 14:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5d4io2lfo4vp70kk3m1gpucgm4","2008-02-04 12:30:52","2008-02-04 14:27:13"
"239","2","Platonic Solids  and  Four Color Theorem","2008-02-05 15:00:00",NULL,"HA 335","Molly Fenn",,"University of Massachusetts Amherst",,,"Graph theory is an area of mathematics that requires very little introduction before some cool problems can be understood and solved. We will start from the basic definitions and examine proofs (and false proofs!) of two historically interesting problems, classifying all regular polyhedra and coloring maps with as few colors as possible.

Molly Fenn is a candidate for Teaching Assistant Professor Position.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a19qd01865ejlr4u3utt368jag","2008-02-04 12:45:13",NULL
"240","15","Estimating Rocket Parameters from Flight Data","2008-02-08 12:15:00",NULL,"HA 274","John Peach",,"MIT Lincoln Laboratory","Kelly Dickson",,"Join us for a FREE PIZZA LUNCH and talk by NCSU alum John Peach.  John will be available after his talk for questions about MIT Lincoln Lab career opportunities and will be at the Engineering Career Fair all day Thursday, February 7th.  

------------------------------------------------

Position and velocity measurements of a missile during the boost phase of flight permit estimates of the motor I_{SP} (a measure of motor efficiency) and mass ratio (mass burn rate to initial mass). From these, bounds may be developed for possible trajectories over the remainder of the flight. Good estimates of the parameters also allows estimates of the launch location and time. The ability to infer launch and terminal strike locations of a missile during boost greatly enhances the warfighters capability to defend against the threat. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/emao6ihv2okagthsjcjdo6sboc","2008-02-04 15:28:05",NULL
"241","2","The abc Conjecture","2008-02-07 15:00:00",NULL,"HA 335","Alina Duca",,"Vassar College",,,"It is often the case in number theory that a reasonable question
is very easy to ask yet extremely difficult or even impossible
to answer. The most famous example, of course, is Fermat’s Last Theorem, the proof of which eluded mathematicians for more than 300 years.

In recent years a problem has arisen for which the search for
a proof might turn out to be as turbulent as Fermat’s Last Theorem. The abc conjecture was formulated in 1985 by J.Oesterle and D.Masser. It is very easy to state, yet nonetheless has far-reaching implications throughout number theory, and it is probable that if a proof is found, it too will have deep
consequences beyond the conjecture itself.

In mathematics it is often possible to translate a problem from
one area to another, in the hope that the resulting question is
easier to tackle and offers insight for the original. One of
the most fruitful analogies in mathematics is that between
the integers and the ring of polynomials. We will discuss first
the abc conjecture for polynomials, then we will see how this
theorem can be translated into the abc conjecture about
ordinary integers.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2e7ijqa8rg14u12ataka93hufs","2008-02-04 15:44:07","2008-02-04 15:59:49"
"242","4","Vanishing viscosity in the presence of a boundary","2008-02-11 15:00:00",NULL,"HA 335","Jim Kelliher","http://www.math.brown.edu/~kelliher/","Brown University",,,"The behavior of an incompressible fluid as we let its viscosity approach zero is poorly understood when a boundary is present. Understanding this behavior is of both theoretical and practical interest. The most natural question to ask is whether in this vanishing viscosity limit solutions to the Navier-Stokes equations, which describe an incompressible viscous fluid, converge in the energy norm to a solution to the Euler equations, which describe an incompressible inviscid fluid. Under the assumption that the viscous fluid remains stationary on the boundary (no-slip boundary conditions) this is one of the oldest and most important questions in mathematical fluid mechanics, and one whose full solution does not appear likely to arrive anytime soon. I will describe some of the existing partial results concerning the vanishing viscosity limit and related problems, and will mention some potentially tractable approaches to extend some of these partial results.

Faculty, students and post-docs are encouraged to attend.

Dr. Kelliher is a candidate for an assistant professorship in the mathematics department.

Tea will be served at 2:30pm before the seminar, in HA 243.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/56emlkh987ftqq6ph1biak4it8","2008-02-06 18:03:45","2008-02-08 10:56:17"
"243","14","Departmental Tea and Cookies","2008-02-07 14:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9nih938q6n49sp0gd1bi4f7u98","2008-02-07 14:21:15",NULL
"244","2","Recursive structures in the cohomology of flag varieties","2008-02-08 14:30:00",NULL,"HA 335","Edward Richmond","http://www.unc.edu/~erichmon/","UNC Chapel Hill",,,"Let Gr(r,n) denote the Grassmannian of r-dimensional subspaces in some fixed n-dimensional complex vector space.  In this  talk, we will look at some results about Schubert varieties in Gr(r,n)  and their connections to cohomology.  In particular, we ask under what conditions is a product of Schubert classes nonvanishing in cohomology  (sometimes called Schubert calculus).   The answer to this question can be given in terms of a recursive algorithm known as Horn recursion.  We  will also look at applications of Schubert calculus to enumerative geometry and some generalizations of Horn recursion to partial flag varieties.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f48thrbbjk27svcbtbgsjg25tg","2008-02-08 10:55:02","2008-02-08 10:57:11"
"245","14","Departmental Tea and Cookies","2008-02-08 14:00:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dqgm0033q1jkougc9n3f2avdpo","2008-02-08 11:13:48",NULL
"246","4","Dissipative homoclinic loops and rank one chaos","2008-02-12 15:00:00",NULL,"HA 335","William Ott","http://www.cims.nyu.edu/~ott","Courant Institute of Mathematical Sciences",,,"I will discuss my recent work with Qiudong Wang on the existence of strange attractors with SRB measures for periodic perturbations of differential equations that admit homoclinic loops.  Our work is based on the recent theory of rank one maps developed by Wang and Young.

Faculty, students and post-docs are encouraged to attend.

Dr. Ott is a candidate for an assistant professorship in the mathematics department.

Tea will be served at 2:30pm in HA 243.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1jslm0r8669d8o5gdi8nqus3u4","2008-02-08 16:44:07","2008-02-11 11:06:33"
"247","14","Departmental Tea and Cookies","2008-02-12 14:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6k1ip3eljsuu57t676tqeo4jn4","2008-02-09 15:10:58",NULL
"248","14","Departmental Tea and Cookies","2008-02-11 14:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/o3c878l883el5deum11ahefnog","2008-02-09 15:13:37",NULL
"249","19","Some Results on the Conjugacy Decomposition of a Reductive Monoid","2008-02-11 15:00:00",NULL,"HA 147","Ryan Therkelsen","http://www4.ncsu.edu/~rtherke/","NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jaqmp6ttuktjgvgvr1ki9n8d60","2008-02-11 09:45:07","2008-02-11 11:05:37"
"250","3","Addition theorems via continued fractions","2008-03-10 16:00:00",NULL,"HA 330","Jiang Zeng","http://math.univ-lyon1.fr/~zeng/","Université Claude Bernard Lyon-I, France",,,"We show connections between a special type of addition formulas, a theorem of Stieltjes and Rogers. We use different techniques to derive the desirable addition formulas. We apply our approach to derive special addition theorems for Bessel functions and confluent hypergeometric functions. We also derive several additions theorems for basic hypergeometric functions. Applications to the evaluation of Hankel determinants are also given. This talk is based on a joint work with Mourad Ismail.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/grl1hjuh550a62gstaf9r6qa4k","2008-02-14 13:36:47","2008-02-14 20:39:23"
"251","3","Arithmetical theory of finite groups and applications","2008-02-19 16:00:00",NULL,"HA 335","Jiping Zhang",,"Peking University, China",,,"Arithmetical properties of various invariants of finite groups have been studied intensively, especially in recent years on the sets of character degrees, lengths of conjugacy classes or element orders, etc. We survey some recent progress and applications (including to Cayley graphs).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ljhkioivlm4dpq4melterbmpec","2008-02-18 10:10:10","2008-02-18 10:11:51"
"252","14","Departmental Tea and Cookies","2008-02-19 15:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/26f7kui5u7n5l1aonc6lqdom5o","2008-02-18 12:02:58",NULL
"253","1","Snakes and Ladders","2008-02-22 16:00:00",NULL,"HA 307","Bjorn Sandstede",,"University of Surry, UK",,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/01nf2q9hn3dj8v75lom5fcmsno","2008-02-18 14:48:23","2008-02-18 14:50:50"
"254","14","Departmental Tea and Cookies","2008-02-22 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/t4fqaej3d18ggvm50tg3dt9b6o","2008-02-18 14:53:59",NULL
"255","5","Non-Localizability of Electric Coupling and Gravitational Binding of Charged Objects","2008-02-29 15:00:00",NULL,"HA 274","Matthew Corne",,,,,"The energy momentum tensor in general relativity contains only localized contributions to the total energy--momentum.  Here, we consider a static, spherically symmetric object consisting of a charged perfect fluid.  For this object, the total gravitational mass contains a non--localizable contribution of electric coupling (ordinarily associated with electromagnetic mass).  We derive an explicit expression for the total mass which implies that the non--localizable contribution of electric coupling is not bound together by gravity, thus prohibiting the existence of objects with pure Lorentz electromagnetic mass in general relativity.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4p3b317emsnk0m4pfte0u8lhhg","2008-02-21 10:00:27","2008-02-21 13:02:28"
"256","14","Departmental Tea and Cookies","2008-02-28 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/usmt8l5ear7i6v04cj9bjp5j8o","2008-02-25 00:26:40",NULL
"257","8","Connectivity in Semialgebraic Sets","2008-04-16 15:00:00",NULL,"HA 335","Robert Quinn",,"NCSU","Hoon Hong",,"A semialgebraic set is a subset of real space defined by polynomial equations and inequalities. A semialgebraic set is a union of finitely many maximally connected components. In this talk, we consider the problem of deciding whether two given points in a semialgebraic set are connected, that is, whether the two points lie in the same connected component. In particular, we consider the semialgebraic set defined by f not equal 0 where f is a given bivariate polynomial. The motivation comes from the observation that many important/non-trivial problems in science and engineering can be often reduced to that of connectivity. Due to its importance, there has been intense research effort on the problem. We will describe a method based on gradient fields and provide a sketch of the proof of correctness based on the Morse complex. The method seems to be more efficient than the previous methods in practice.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/imt3f93putgld5grienhugu3k4","2008-02-29 20:32:01","2008-04-11 15:48:14"
"259","14","Departmental Tea and Cookies","2008-03-12 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/v3uocnrkcrakqe0tq8lqoud20s","2008-03-10 16:12:44","2008-03-10 16:13:09"
"260","14","Departmental Tea and Cookies","2008-03-19 15:50:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u72otvbmmnpddidbp03p77ff68","2008-03-17 12:26:11",NULL
"261","19","Free Groups and Topology","2008-03-24 15:00:00",NULL,"HA 147","Evan Wilson",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6eqhaoli683llghrd66bdmjtvk","2008-03-19 10:28:37",NULL
"262","6","Iterative Filtering for a Dynamical Reputation System","2008-04-28 14:00:00",NULL,"HA 274","Cristobald de Kerchove","http://www.inma.ucl.ac.be/~dekerch/","Université Catholique de Louvain-la-Neuve, Belgium","Ilse Ipsen",,"The World Wide Web is making more and more use of interactive  ratings collected from various users. They evaluate books, movies, other users, etc. This form of voting requires a sort of filtering in order to bring order among reliable  and malicious users. I propose a novel iterative method that assigns a reputation to n + m items: n raters and m objects. Each rater evaluates a subset of objects leading to a n x m rating matrix with a certain sparsity pattern. From this rating matrix we give a nonlinear formula to define the reputation of raters and objects. We also provide an iterative algorithm that superlinearly converges to the unique vector of reputations and this for any rating matrix. In contrast to classical outliers detection, no evaluation is discarded in this method but each one is taken into account with different weights for the reputation of the objects. The complexity of one iteration step is linear in the number of evaluations, making our algorithm efficient for large data set. Experiments show good robustness of the reputation of the objects against cheaters and spammers and good detection properties of cheaters and spammers.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ler2mvm7nsjr9840ehek4d87rs","2008-03-19 12:12:42","2008-04-24 10:28:05"
"263","3","Poisson vertex algebras in the theory of Hamiltonian equations","2008-03-24 16:00:00",NULL,"HA 330","Alberto De Sole","http://www.math.harvard.edu/~desole/","Harvard University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/algsem032408.pdf","We discuss some algebraic structures relevant to the theory of Hamiltonian equations and their integrals of motion. In particular, we discuss the relation between the notions of Hamiltonian operator and of Poisson vertex algebra. We also describe how to use pairs of compatible Poisson vertex algebra structures to construct infinite hierarchies of integrable Hamiltonian equations.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4n05sqasrm1qvvle3uf5m88v1o","2008-03-20 08:40:11",NULL
"264","3","The Jacobi identity for vertex operators, and standard A_1^{(1)} and A_2^{(2)}-modules","2008-03-28 16:00:00",NULL,"HA 335","Cristiano Husu","http://www.stamford.uconn.edu/profile_HusuCristiano.htm","University of Connecticut",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/algsem032808.pdf","The Jacobi identity for relative twisted vertex operators is, roughly speaking, the Jacobi identity for vertex operator algebras generalized by means of the correction factors that preserve the structure of the identity in the general case of relative twisted operators. The application of the identity to the A_{1}^{(1)} and A_{2}^{(2)} weight lattices shows how the correction factors form the generalized commutator and anti-commutator relations for the Z-operator construction of standard modules. In the A_{1}^{(1)}-case, multi-operator extensions of the Jacobi identity also describe the relationship between Z-operators and the generating function identities for the annihilating ideals of standard modules.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f856tfp3kn5n9blura0hscpsc0","2008-03-20 08:50:16",NULL
"265","14","Departmental Tea and Cookies - Time Changed","2008-03-28 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fr2lde2q9nsj9efomhdaegngvo","2008-03-24 11:21:04","2008-03-28 10:51:56"
"266","20","Regularization Methods for Fluid Flow Simulations","2008-03-28 15:00:00",NULL,"HA 330","Ricardo Cortez",,"Tulane University",,,"The fluid motion surrounding swimming microorganisms is often modeled using the Stokes equations of fluid motion due to the small length scales. I will present the Method of Regularized Stokeslets and other related ideas that are used to compute Stokes flows interacting with immersed flexible bodies or moving through obstacles. The method treats the flexible bodies as sources of force in the equations and the resulting velocity is the superposition of flows due to all the force elements. Exact flows are derived for forces that are smooth but supported in small spheres, rather than point forces. I will present the idea of the method, some of the known theory and several examples from biological applications.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q56fd5th0ktlk14u9uff1hes24","2008-03-24 11:30:06",NULL
"267","10","Priority Assignment under Imperfect Information on Customer Type Identities","2008-04-01 16:30:00",NULL,"Daniels 218","Serhan Ziya",,"University of North Carolina",,"http://www.or.ncsu.edu/documents/ORSeminar-Dr.Ziya-April12008.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mkaa364khed7oe5nvho5grkcro","2008-03-31 11:47:09",NULL
"268","14","Departmental Tea and Cookies","2008-03-31 14:45:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/j7a04vqtn8nrf1nfpqg3ras0sk","2008-03-31 12:18:03",NULL
"269","14","Departmental Tea and Cookies","2008-04-01 15:00:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n35vkdo1aqg60rn5vlp9c0douk","2008-03-31 12:18:36",NULL
"270","14","Departmental Tea and Cookies","2008-04-09 15:50:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/or5cf6ie7b48ep5g79mc95k4lk","2008-04-07 12:49:55",NULL
"271","7,8","Spectra of Large Random Toeplitz Matrices","2008-04-17 15:00:00",NULL,"HA 330","Professor  Wlodek Bryc",,"University of Cincinnati","Min Kang",,"As the dimension tends to infinity, spectral measures of large random Toeplitz matrices with independent identically distributed entries that have finite second moments converge to the \\\\\\\""universal\\\\\\\"" measure on R. I will review the main ideas in the proof, and what is known as well as what is not known  about the limiting measure. I will also talk about similar results for other \\\\\\\""structured\\\\\\\"" ensembles of symmetric random matrices, including the \\\\\\\""trivial cases\\\\\\\"" of symmetric circulant and \\\\\\\""reversed circulant\\\\\\\"" matrices.

If time permits, I will then talk about \\\\\\\""block-Toeplitz\\\\\\\"" matrices where the limits of spectral measures are determined from the system of equations stated by Girko, and which in \\\\\\\""modern approach\\\\\\\"" arises from matrix-valued free probability.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bl19nrmcnl0tiei20ktv5dbv80","2008-04-09 23:37:10","2008-04-12 13:16:13"
"272","15","SIAM Chapter Meeting","2008-04-16 15:30:00",NULL,"HA 274","Kelly Dickson","http://www.math.ncsu.edu/GroupsOrgs/SIAM/index.html","NCSU","Kelly Dickson",,"Please join us for the last SIAM Chapter meeting for the spring term.  This is an important meeting as we will be voting on new officers and discussing events for the upcoming academic year.  As usual, we will provide snacks!  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6f13s2cmv8mp2jlmue5o0d6624","2008-04-10 12:39:35","2008-04-10 12:42:35"
"273","14","Departmental Tea and Cookies","2008-04-17 15:50:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5487n2o888csmsrue61jiutvps","2008-04-14 12:38:29",NULL
"274","15","Opportunities in Computational Applied Mathematics at Sandia National Laboratories","2008-04-24 16:30:00",NULL,"HA 274","Brian Adams","http://www.sandia.gov/~briadam/","Sandia National Laboratories","Kelly Dickson",,"Through this presentation I will relate my 2-1/2 year experience working in a mathematics and computer science research group at Sandia, a national security laboratory.  The broad mission areas of the lab foster research in disciplines including engineering, materials, bioscience, energy and water, infrastructure security, scalable scientific computation, and beyond.  Opportunities in computational mathematics span from theory through algorithms and software to applications of national importance.

Through two examples I will demonstrate the potential mix of theory and applications work possible in this environment:  (1) A social contact network-based model for early epoch simulation of disease outbreaks and bioterror incidents, which uses agent-based simulation, reduced-order modeling, graph analysis, and scalable parallelism; and (2) DAKOTA, an open-source software suite for optimization, sensitivity analysis, and uncertainty quantification.  In particular, DAKOTA\'s reliability analysis methods employ a mix of probability, optimization, and surrogate (meta-) modeling; I will demonstrate their application to robust micro-electro-mechanical system design.

While some technical details will be offered, the majority of this talk will be accessible to graduate and advanced undergraduate students with interest in mathematics, computer science, or statistics.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5lcoo1kpre33e0travpdmebqnk","2008-04-15 11:47:10",NULL
"275","6","Coefficients of Ergodicity: An Introduction","2008-04-23 15:00:00",NULL,"HA 335","Ilse Ipsen","http://www4.ncsu.edu/~ipsen/index.html","Department of Mathematics, NCState",,,"So-called «coefficients of ergodicity» were introduced by Markov in 1906 to 
describe the long-term behaviour of inhomogeneous Markov chains.
We interpret these coefficients as bounds on eigenvalues and singular
values of stochastic matrices, and extend them to general complex
matrices.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u4clrr3rbbs0ob217nnc0pkrs0","2008-04-15 17:05:29","2008-04-16 08:52:19"
"276","14","Young Tableaux","2008-04-23 14:30:00",NULL,"HA 274","Jennifer Carter",,"NC State Undergraduate",,,"I will give a brief introduction to Young tableaux and some of
their uses.  I will discuss the one-to-one correspondence between pairs of semi-standard tableaux having the same shape and permutations.  I will also show how tableaux can be used to count matrices with specific row and column sums.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b4o7g0ef9jk324og0cfc9erfb0","2008-04-17 10:59:01","2008-04-22 10:44:03"
"277","14","Pricing Real Estate Development Options","2008-04-23 14:30:00",NULL,"HA 274","Albert M. Blackmon, Jr.",,,,,"A discrete-time pricing model to value a real estate development
project, that will be used in the future to determine the price of an option to develop a parcel of land, will be presented.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gva510kv7lak9tf3en2tp8hhuo","2008-04-17 10:59:43","2008-04-22 10:44:40"
"278","3","L-infinity modules vs OCHA\'s (Open-Closed Homotopy Algebras)","2008-04-25 16:00:00",NULL,"HA 335","Tom Lada","http://www4.ncsu.edu/~lada/","NC State University",,,"We will review these two related versions of the action of an L-infinity algebra on a vector space. OCHAs were inspired by open-closed string field theory. Several examples will be exhibited.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fh0bpm2gnvbe4t95filk30j1b0","2008-04-21 08:50:31",NULL
"279","14","Awards Reception","2008-04-23 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/aek37cjf8qt1t07u3jofio9nlg","2008-04-21 11:25:05","2008-04-21 12:22:47"
"280","21","Geometry and Analysis of Dynamical Systems Conference to Celebrate the Mathematical Contributions of Xiao-Biao Lin and Stephen Schecter","2008-02-22 09:00:00","2008-02-24 17:00:00","Harrelson","Yingfei Yi, Carmen Chicone, Margaret Beck, Tasso Kaper, Bjorn Sandstede, Todd Kapitula, Weishi Liu, Anna Ghazaryan, Jack Hale, Kening Lu, Martin Wechselberger, Kris Jenssen, Wenxian Shen, Kevin Zumbrun, David Schaeffer, Chongchun Zeng,Constantine Dafermo",,,,NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gae8ui0fdo90q3kihqt6cl4a40","2008-04-21 13:22:52",NULL
"281","14","Awards Day Ceremony","2008-04-23 16:00:00",NULL,"HA 201",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nmvs9nvq4aj4pqeasnsjvj12p4","2008-04-23 11:40:40","2008-04-23 11:45:52"
"282","2","Dirichlet Duality and the Non-linear Dirichlet Problem","2008-05-01 16:00:00",NULL,"HA 307","Blaine Lawson",,"SUNY Stony Brook",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/iv7c9hm1e4clfmk3n7f41dkeb4","2008-04-23 11:44:44",NULL
"283","14","Departmental Tea and Cookies","2008-05-01 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u6veuftbpui37dss0tmv282lik","2008-05-01 13:54:42",NULL
"284","14","Departmental Tea and Cookies","2008-05-28 15:00:00",NULL,"HA 244",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jt5u4hunt3ltn7pk8fqrgvdns0","2008-05-28 11:32:09",NULL
"285","14","Departmental Tea and Cookies","2008-06-11 15:00:00",NULL,"HA 244",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/v9qnm7328ou83vg0pffofr5q5s","2008-06-11 13:21:49",NULL
"286","14","Departmental Tea and Cookies","2008-06-18 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u48a8rlhf54a381pvulhi669vo","2008-06-18 12:17:11",NULL
"287","14","Departmental Tea and Cookies","2008-07-02 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vounkahsbbas53vtb2rklo4q74","2008-07-07 14:04:19",NULL
"288","14","Departmental Tea and Cookies","2008-07-16 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9hf6iuco1ji18s11q9emnqgiic","2008-07-17 17:11:59",NULL
"289","14","Departmental Tea and Cookies","2008-07-09 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2jmm4383jt1t8nhsukui53t674","2008-07-17 17:16:31",NULL
"290","14","Departmental Tea and Cookies","2008-07-30 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jcjn3kb90ai1lomijsiao6em1c","2008-07-30 12:35:00",NULL
"291","14","Fall Departmental Meeting","2008-08-21 16:00:00",NULL,"HA 201",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/58ad7cgpclb9us83qfu87kbegc","2008-08-12 00:15:39",NULL
"292","6","Prediction of patient specific parameters in a cardiovascular-respiratory model","2008-12-02 15:00:00",NULL,"HA 330","Mette Olufsen","http://www4.ncsu.edu/~msolufse/","NC State","NA Seminar",,"The cardiovascular system has given rise to numerous models ranging from lumped parameter models to complex 3D fluid dynamics models. One challenge for many of these models is to allow validation using patient specific data. This often puts additional restraint on the models. Typically, models are validated using noninvasive data, and often these data are sparse compared to the complexity of the models. In this talk I will discuss problems related to parameter estimation using a lumped compartmental model developed to predict blood flow, blood pressure, and partial pressure of CO2 in the expiratory air for a patient with congestive heart failure. The goal with this model is to be able to estimate patient specific parameters that allow prediction of experimental data. To do so we solve a nonlinear least squares problem minimizing the difference between computed and measured quantities. A challenge is that this model has many model parameters and that these parameters may be correlated or insensitive. I will show how sensitivity analysis and subset selection can be used to pick a small set of identifiable parameters, and how these parameters can be estimated using the Levenberg-Marquardt variant of the Gauss-Newton optimization method.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tljuk4jnkgtqt7rutnvcbum2ts","2008-08-12 08:15:19","2008-11-21 08:20:25"
"294","6","Fast Algorithms for Integral Equations","2008-11-18 15:00:00",NULL,"HA 330","Tim Kelley","http://www4.ncsu.edu/~ctk/","NC State","NA Seminar",,"We will discuss a class of fast algorithms for linear and
nonlinear integral equations. These are two-level algorithms
based on the classic Atkinson-Brakhage method from the 1970s.
We will present more efficient approach which uses a matrix-free
Newton-Krylov iteration on the coarse mesh and does the
fine-to-coarse intergrid transfer with an average. We will then
apply the approach to the Ornstein-Zernike (OZ) equations for atomic
fluids and some extensions of the OZ equations for molecular fluids. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sfmm6ggtvlqt3908m23kl1sv6o","2008-08-12 08:29:36","2008-11-17 10:41:24"
"295","6","A numerical regularization technique for multi-scale, linear transport models","2008-09-23 15:00:00",NULL,"HA 330","Cory Hauck","http://cnls.lanl.gov/External/people/Cory_Hauck.php","Los Alamos National Laboratory","Pierre Gremaud",,"
We present a regularization technique for the P_N equations:  a linear hyperbolic system of PDEs that is commonly used to model particle transport through a material medium.  In collision-dominated regimes,  the P_N equations have a well-known asymptotic limit that is described by a standard diffusion equation.  However, this limit is difficult to capture with conventional hyperbolic solvers that are based on the upwind methodology, due to (i) excessive numerical dissipation and (ii) a stiff CFL condition.   The regularization technique, which is derived by splitting the P_N system into fast and slow dynamics, does capture the proper diffusion limit and provides a useful tool for multi-scale problems with regions of both high and low collisionality.  We present initial results for some one-dimensional test problems and discuss areas for continued development.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/maeplena0mkhci4km6hdsvpoec","2008-08-12 08:32:49","2008-09-10 13:51:33"
"296","6","Orthogonal Polynomials, Moments, Measure Deformation, Dynamical  Systems, and SVD Algorithm","2008-10-21 15:00:00",NULL,"HA 330","Moody Chu","http://www4.ncsu.edu/~mtchu/","NC State","NA Seminar","http://www4.ncsu.edu/~ctk/NA_Seminar/NA_08_Chu.pdf","Iterates generated from discrete dynamical systems such as the QR algorithm
and the SV D algorithm are time-1 samples of solutions to the Toda lattice
and the Lotka-Volterra equation, respectively. In this talk we present some
recent discoveries that connect diverse topics such as soliton theory, integrable
systems, continuous fractions,  functions, orthogonal polynomials, Sylvester
identity, moments, and Hankel determinants together. Of particular interest
are the three facts that
1. Each of the Toda lattice and the Lotka-Volterra equation governs the
evolution of a certain class of orthogonal polynomials whose orthogonality
is determined by a specic time-dependent measure.
2. Since the measure deformation is explicitly known, moments can be calcu-
lated which, when properly assembled, lead to the conclusion abstractly,
but literally, that the iterates of the QR algorithm and the SV D algorithm
can be expressed in closed-form!
3. Hankel determinantal solutions are too complicated to be useful. However,
a \smart"" integrability-preserving discretization of the Lotka-Volterra equa-
tion can yield a new SV D algorithm.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p0ikpvdt4098fsccm22gp7gs2k","2008-08-12 12:06:18","2008-10-20 15:44:54"
"297","6","A Particle Method for the EPDiff Equation","2008-11-11 15:00:00",NULL,"HA 330","Alina Chertock","http://www4.ncsu.edu/~acherto/","NCSU","NA Seminar",,"ABSTRACT:
We consider a model of active fluid transport described by an evolutionary equation, known as the the Euler-Poincaré(EPDiff) equation.  The EPDiff equation arises in many scientific applications. In particular, it appears in the nonlinear dynamic of shallow water waves, and coincides, for example, with the Camassa-Holm equation of shallow water in 1-D and 2-D, and with the averaged template matching equation for computer vision in higher dimensions. The EPDiff singular solutions are  contact discontinuities, called peakons. The key feature of the peakons is that they carry momentum; so the wave front interactions they represent are collisions, in which momentum is exchanged.  This is very reminiscent to the KdV solitons behavior in 1-D.

We numerically investigate the EPDiff dynamics of contact interactions using particle methods. We show that he discretization by means of the particle method preserves the basic Hamiltonian, the weak and variational structure of the original problem and respects the conservation laws associated to the symmetry under the Euclidean group. We use this symmetry to reduce the dimensionality of the system, and thus to simplify the theoretical and, especially, numerical analysis of the dynamics of  peakons and their interactions.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gcg7g2e6e8ut51rv96srf1hcr4","2008-08-14 12:16:04","2008-11-04 11:20:17"
"298","3","Generalizing ""2"":  The Combinatorics of l-Sequences","2008-08-22 16:00:00",NULL,"HA 335","Carla D. Savage","http://www4.ncsu.edu/~savage/","NC State University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC082208.pdf","The l-sequences, cousins of the Fibonacci sequence, are defined by the recurrence a(n) = l a(n-1) - a(n-2), with initial conditions a(0)=0, a(1)=1. They arise in diverse areas of combinatorics and we will highlight some of their fascinating properties.

Many fundamental identities in combinatorics involve binomial coefficients and their interpretations. We use l-sequences to define the ""l-nomial coefficient"", a generalization of the binomial coefficient, and consider extending classical binomial combinatorics to the ""l-world"".",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cebedm2ffgv5878mi8hknriin8","2008-08-17 08:50:11","2008-08-19 19:43:42"
"299","3","Noncrossing partitions and intersections of shards","2008-09-19 16:00:00",NULL,"HA 335","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC091908.pdf","The context for this talk is the combinatorics of a finite Coxeter group (reflection group) W. Starting with the set of reflecting hyperplanes for W, we cut certain hyperplanes along their intersections with other hyperplanes according to a simple rule.  The resulting pieces of hyperplanes are called the shards of W.  The set Psi(W) of arbitrary intersections of shards is easily seen to be a lattice under reverse containment.  More surprisingly, Psi(W) is in bijection with W, so the lattice Psi(W) can be viewed as a partial order on W.

The lattice Psi(W) turns out to have surprising connections with seemingly unrelated questions.  The motivating connection is with the noncrossing partition lattice NC(W).  We identify NC(W) with a sublattice of Psi(W).  Specifically, taking a certain subset of the shards (the ""sortable"" shards), NC(W) is identified with the set of arbitrary intersections of sortable shards.  This provides, in particular, a new proof that NC(W) is a lattice.  We also discuss close connections to semi-invariants of quivers.

For those less familiar with Coxeter groups, I will illustrate the definitions and results with a running example, talking W to be the symmetric group S_4.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kb9pcckur7s8fb01v7k1egsm70","2008-08-19 19:27:30","2008-09-19 13:46:24"
"300","3","Algebraic and combinatorial aspects of Gaussian graphical models","2008-10-31 16:00:00",NULL,"HA 335","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC103108.pdf","Graphical models are a family of statistical models where graphs are used to represent dependence structures between collections of random variables.  For example, a directed edge pointing from random variable X to random variable Y might mean that X affects Y in some way.

In the case where all the random variables are jointly normal, the model (that is, the set of all possible probability distributions consistent with a given graph) is parametrized by an algebraic subset of the cone of positive definite covariance matrices.  While the constraint sets of these models are well understood in the case that all random variables are observed, it is a major open problem to describe these sets in the case that some of the random variables are hidden.

I will describe two results for Gaussian graphical models with hidden variables.  The first is a complete characterization of algebraic constraints on hidden tree models.  The second is a global combinatorial characterization of the vanishing of subdeterminants of the covariance matrix in terms of a new separation criterion in the graph.  Along the way, we will see some familiar algebraic objects and combinatorial tools, like degenerations of the Grassmannian and the Gessel-Viennot Theorem.

I will try to make the statistical and algebraic background accessible to a broad audience.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1hgt7jferllahp21mk3rdrno6o","2008-08-19 19:31:33","2008-09-21 21:44:43"
"302","3","Integrable hierarchies, Gromov-Witten invariants, and complex oscillating integrals","2008-11-14 16:00:00",NULL,"HA 335","Todor Milanov","http://www4.ncsu.edu/~temilano/","NC State University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC111408.pdf","By definition the Gromov-Witten (GW for brevity) invariants of a symplectic manifold X, enumerate holomorphic curves in X, satisfying various incidence constraints. Their precise definition is quite involved and uses some of the latest achievements of Mathematics. It is natural to organize the GW invariants in a generating function D_X. One of the fundamental conjectures in Gromov-Witten theory says that D_X is a highest weight vector for the Virasoro algebra. Apparently there is some exciting and deep interaction between algebra and geometry which is still far from being understood. 

In this talk, I would like to describe an approach to GW invariants based on complex oscillating integrals and integrable hierarchies. It is known that for quite large class of manifolds, such as the Grassmanians, toric manifolds, and flag manifolds, the corresponding GW invariants can be described in terms of the asymptotical expansions of certain families of oscillating integrals. Each manifold X comes with its own family, which is known as the mirror model of X. It turns out that some of these families lead to integrable hierarchies and representations of infinite-dimensional Lie algebras. This is exactly the place where I have made some contributions to the subject and which will be discussed in my talk. In general, I am expecting that each mirror family leads to an integrable hierarchy or/and to a representation of some infinite-dimensional Lie algebra. However, solving this problem requires new ideas. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6cdpssn5hjbdpb298oph546avo","2008-08-19 19:41:23","2008-11-11 18:56:48"
"303","3","Coxeter combinatorics","2008-11-07 16:00:00",NULL,"HA 335","Drew Armstrong","http://www.math.umn.edu/~armstron/","University of Minnesota",,,"In 1935 Coxeter classified all of the finite groups generated by reflections. We now call these groups finite Coxeter groups; the motivating example is the symmetric group S_n, in which the transposition (i,j) is thought of as a reflection in the hyperplane x_i=x_j. It turns out that many classical combinatorial objects can be defined in terms of the symmetric group in such a way that their definition extends uniformly to all finite Coxeter groups. This leads to a beautiful mixture of algebra and combinatorics. I will describe several classical concepts that extend in this way, including: sorting algorithms, catalan numbers, noncrossing partitions, and polygon triangulations.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fcepic0crb42fku949cts60f3k","2008-08-19 22:20:00","2008-10-27 08:47:36"
"304","3","A generalization of the Euler-Glaisher partition bijection","2008-09-26 16:00:00",NULL,"HA 335","Andrew Sills","http://math.georgiasouthern.edu/~asills/","Georgia Southern University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC092608.pdf","In 1748, Euler published his Introductio in Analysin Infinitorum.  Chapter 16 of this work is the first systematic study of integer partitions in the mathematical literature.  In it, he introduces infinite product generating functions and uses them to derive what is now known as Euler's partition identity, an English translation of which reads as follows: ""The number of different ways a given number can be expressed as the sum of different whole numbers is the same as the number of ways in which the same number can be expressed as the sum of odd numbers, whether the same of different.""   In modern erminology, the preceding is rephrased as ""the number of partitions of n into distinct parts equals the number of partitions of n into odd parts.""

In 1883, J.W.L. Glaisher published the first bijective proof of Euler's partition identity, along with a natural generalization: ""the number of partitions of n where no part appears more than m-1 times equals the number of partitions of n where no part is divisible by m.""

By combining a construction of P.A. MacMahon called ""partitions of infinity"" and knowledge of G.E. Andrews' ""partition ideals of order 1"" with Glaisher's bijective proof of Euler's identity, we are led to discover a large class of partition identities with straightforward bijective proofs.

This is joint work with James Sellers and Gary Mullen of Penn State.

All terms will be defined and illustrated with concrete examples, so the required mathematical background will be minimal.  Students as well as faculty are encouraged to attend.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/coaei8qbbmp3ge38t2jl54u7tk","2008-08-20 07:06:46","2008-09-21 21:45:37"
"305","3","Probabilistic proofs of hook length formulas involving trees","2008-10-20 15:00:00",NULL,"HA 335","Bruce E. Sagan","http://www.math.msu.edu/~sagan/","Michigan State University and NSF",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC102008.pdf","Let T be a rooted tree with n distinguishable vertices. We use T to stand for the vertex set of T. An increasing labeling of T is a bijection l:T->{1,2,...,n} such that l(v)<=l(w) for all descendents w of v. Let f^T be the number of increasing labelings. The hooklength, h_v, of a vertex v is the number of descendents of v (including v itself). The hook length formula for trees states that f^T = n! / product_{v in T} h_v.

There is a similar formula for the number of standard Young tableaux of given shape where a hooklength is the cardinality of a set which resembles a physical hook. Greene, Nijenhuis, and Wilf gave a beautiful probabilistic proof of the tableau formula where the hooklenths enter in a very natural way.

Recently, Han discovered a formula which has the interesting property that hooklengths appear as exponents. Specifically, let B(n) be the set of all n-vertex binary trees (each vertex has no children, a left child, a right child, or both children). Han proved that sum_{T in B(n)} product_{v in T} 1 / h_v 2^{h_v-1}} = 1/n! using algebraic manipulations. We will show how to give a simple probabilistic proof of this equation as well as various generalizations. We will also pose some open questions raised by this work.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9h0fsu6457412ci6qqjlpe1p6g","2008-08-20 07:11:07","2008-08-21 08:31:28"
"306","14","Departmental Tea and Cookies","2008-10-20 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gg8ukp28pi4eifdkgns5qat934","2008-08-20 09:36:06",NULL
"307","2","The Division of Mathematical Sciences inside the National Science Foundation","2008-10-20 13:30:00",NULL,"HA 320","Bruce Sagan",,"National Science Foundation and Michigan State University","Nathan Reading","http://www4.ncsu.edu/~nreadin/SaganNSF.pdf","I will describe the Division of Mathematical Sciences (DMS) as part of the National Science Foundation (NSF).  I will begin by putting DMS in perspective within NSF and the Directorate of Mathematical and Physical Sciences (MPS).  I will then talk about the various disciplinary and workforce/infrastructure programs inside DMS, ending with a summary of the NSF's proposal review criteria and list of things to keep in mind when submitting a proposal.  There will be ample time for questions.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/28o1rkqscmj30uoe0dffascf5k","2008-08-20 09:37:50","2008-10-17 10:45:59"
"308","4","Singular nonlinear  traveling wave equations: dynamical system approach","2008-11-12 15:00:00",NULL,"HA 330","Jibin Li",,"Zhejiang Normal University and Kunming University of Science and Technology","Xiao-Biao Lin",,"Two very active fields in nonlinear science are (1) solitons and complete integrability of nonlinear wave equations, and (2) bifurcations and chaos in dynamical systems.  A homoclinic orbit of a traveling wave system (ODE) corresponds to a solitary wave solution of a nonlinear wave equation (PDE). This fact provides an intersection point for these two fields. The aim of this talk is to explain how the bifurcation theory method of dynamical systems can be used to find traveling wave solutions and understand their dynamics.  We will emphasize singular waves  for some classes of nonlinear evolution equations, and systems with discontinuities.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ojaubhm3i3lob7rrqhid05vv7g","2008-08-20 10:00:06","2008-10-28 10:53:52"
"309","3","Pluecker coordinates associated with a planar network","2008-09-05 15:00:00",NULL,"HA 335","Kelli Talaska","http://www.math.lsa.umich.edu/~kellicar/","University of Michigan",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC090508.pdf","For a planar directed graph G, Postnikov's boundary measurement map sends positive weight functions on the edges of G onto the appropriate totally nonnegative Grassmann cell. We establish an explicit formula for Postnikov's map by expressing each Pluecker coordinate as a ratio of two combinatorially defined polynomials in the edge weights, with positive integer coefficients.  In the non-planar setting, we show that a similar formula holds for special choices of Pluecker coordinates.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dpifilqt7t7vtcgiav7unf4f4o","2008-08-20 10:11:24","2008-08-31 08:39:41"
"310","4"," Stability of fronts for gasless combustion in a one-dimensional solid","2008-08-27 15:00:00",NULL,"HA 330","Steve Schecter","http://www4.ncsu.edu/~schecter","North Carolina State University",,,"For gasless combustion in a one-dimensional solid, we show a type of nonlinear stability of the physical combustion front: if a perturbation of the front is small in both a spatially uniform norm and an exponentially weighted norm, then the perturbation stays small in the spatially uniform norm and decays in the exponentially weighted norm, provided the linearized operator has no eigenvalues in the right half-plane other than zero. Using the Evans function, we show that the zero eigenvalue must be simple. Factors that complicate the analysis are: (1) the linearized operator is not sectorial, and (2) the linearized operator only has good spectral properties when the weighted norm is used, but then the nonlinear term is not Lipschitz.  The result is nevertheless physically natural. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ihhdrnd1rd0m4rqd8208i1pe3o","2008-08-20 10:20:21","2008-08-27 09:39:12"
"311","3","Delannoy numbers and the orthogonality of certain Jacobi polynomials","2008-09-12 15:00:00",NULL,"HA 335","Gábor Hetyei","http://www.math.uncc.edu/~ghetyei/","University of North Carolina - Charlotte",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC091208.pdf","It has been observed more than 50 years ago that the central Delannoy numbers may be obtained by substituting 3 into the Legendre polynomials. We introduce a weighted lattice path enumeration model which explains this connection and extends it to all Delannoy numbers and substitutions of 3 into the appropriate Jacobi polynomials. Inspired by this model we provide a combinatorial, non-inductive proof of the orthogonality of the Jacobi polynomials with fixed natural number parameters.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j9ck7k9rmhnk65v2dl8bpo195g","2008-08-21 14:10:15","2008-09-08 14:20:51"
"312","3","Non-linear generalizations of the affine Lie algebra hat{sl_2}","2008-08-29 15:00:00",NULL,"HA 335","Bojko Bakalov","http://www4.ncsu.edu/~bnbakalo/","NC State University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC082908.pdf","The most ubiquitous and important Lie algebra, sl_2, consists of all 2 by 2 matrices over the complex numbers whose diagonal entries add to zero, equipped with the Lie bracket [A,B]=AB-BA. The corresponding affine Kac-Moody Lie algebra  has many applications in mathematical physics and various areas of mathematics. The elements of hat{sl_2} can be organized in generating series called quantum fields in physics, thus providing an example of a vertex algebra. We classify certain vertex algebras with three generators, which can be viewed as non-linear generalizations of hat{sl_2}. We construct free-field realizations of our algebras extending the Wakimoto realization of hat{sl_2}. We also compute the corresponding associative Zhu algebras and obtain certain non-linear generalizations of the universal enveloping algebra of sl_2 introduced by S.P. Smith. Only knowledge of linear algebra will be assumed: all necessary notions such as Lie algebras and vertex algebras will be introduced in the talk.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k6glvfsr86gnauoe2d4deal0tg","2008-08-21 17:21:49",NULL
"313","4","Virtual rheoscopic fluids and ellipsoid dynamics","2008-10-29 15:00:00",NULL,"HA 330","Peter Mucha","http://www.unc.edu/~mucha","University of North Carolina at Chapel Hill","Steve Schecter",,"We present a visualization technique for simulated fluid dynamics data
that visualizes the gradient of the velocity field in an intuitive
way.  Our work is inspired by rheoscopic particles, which are small,
flat particles that, when suspended in fluid, align themselves with
the shear of the flow.  We adopt the physical principles of real
rheoscopic particles and apply them, in model form, to 3D velocity
fields, by extension of a technique due to Bretherton.  By simulating
the model behavior and reflectance of these particles we are able to
render 3D simulations in a way that gives insight into the dynamics of
the system.  The results can be rendered in real-time, through a
combination of pre-computations and fast ray-tracing on the GPU,
allowing the user to inspect the simulation from all perspectives.  We
demonstrate our method on several different simulations, showing their
complex dynamics in the process.  We also explore both the accuracy
and the limitations of the model dynamics.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b8pe4lh16ph5116ff54g9uvkjs","2008-08-25 09:31:57","2008-10-21 14:00:53"
"314","3","Vertex-algebraic structures underlying recursions","2008-10-03 16:00:00",NULL,"HA 335","Corina Calinescu","http://www.math.ohio-state.edu/~calinescu/","Ohio State University",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC100308.pdf","In this talk I will report on recent developments in the study of principal subspaces of the standard modules for affine Lie algebras of type A, D or E. I will discuss a generators-and-relations result for these subspaces and recursions satisfied by the graded dimensions of the principal subspaces. This is joint work with Jim Lepowsky and Antun Milas.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hpjovn548pbtfvdfj75s18h1l4","2008-08-26 11:54:40","2008-09-28 17:06:22"
"315","3","Hilbert functions of Gorenstein algebras","2008-11-21 16:00:00",NULL,"HA 335","Uwe Nagel","http://www.ms.uky.edu/~uwenagel/","University of Kentucky",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC112108.pdf","Hilbert functions of Gorenstein algebras are of great interest in various areas. They often  arise in disguised form. An example is the f-vector of a triangulation of a sphere that records the number of faces in each dimension.

Gorenstein Hilbert  functions are completely classified in polynomial rings with up to three variables. The condition is that the h-vector has to be a so-called SI-sequence. In particular, it is  unimodal.  However, an example of Stanley in 1978 and subsequent work by Bernstein, Boij, Iarrobino, and Laksov showed that whenever the number of variables is at least five there are  Gorenstein algebras whose Hilbert function is not even unimodal. The characterization of these Hilbert functions remains a mystery.  However, recently there has been some progress. We describe these results and discuss several concrete open problems.

The talk will be accessible to a broad audience.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7iaaepndll3rrbnsa7cgpp47uc","2008-08-26 21:00:42","2008-11-16 21:30:10"
"316","4","Stirring and mixing: topology, optimization, and those pesky walls","2008-10-14 16:00:00",NULL,"Riddick 315","Jean-Luc Thiffeault","http://www.math.wisc.edu/~jeanluc","University of Wisconsin","Karen Daniels, Physics Dept.","http://www4.ncsu.edu/~schecter/de_seminar/thiffeault.pdf","[Joint Complex Matter and Biophysics-Differential Equations Seminar.  Tea at 3:30 in Riddick 415.]
I review various aspects of current research, both experimental and
theoretical, on stirring and mixing in fluids.  Three main threads are
followed: (1) how topological features influence mixing effectiveness;
(2) how this leads to novel optimization methods; and (3) how one has to
be mindful of wall effects, which can dramatically slow down mixing.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ddkjq5a0rn6om51tob9a4ndems","2008-08-27 09:37:36","2008-10-07 10:15:36"
"317","22","Avalanches and the Brazil Nut Effect","2008-09-04 15:00:00",NULL,"HA 330","Michael Shearer","http://www4.ncsu.edu/~shearer","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/090408.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lq5b269cqhf8iievveetgthhd0","2008-08-28 10:14:32","2008-09-02 13:23:48"
"318","22","Tiling the Aztec diamond with dominoes","2008-09-11 15:00:00",NULL,"HA 330","Nathan Reading","http://www4.ncsu.edu/~nreadin","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/091108.pdf","The study of domino tilings goes back to early 20th century physicists, who used domino tilings in a statistical-mechanical model of diatomic molecules on a surface. A domino is a 2-by-1 rectangle. Tiling a region in the plane by dominoes means completely covering the region with non-overlapping dominoes. Consider the following simple question: How many ways can a given region of the plane be tiled by dominoes? For example, there are two domino tilings of a 2-by-2 square. For a general rectangular region, the formula looks strange and is difficult to prove. For a different planar region called the Aztec diamond, the formula is quite simple. We’ll discuss and illustrate a beautiful proof of the formula due to Elkies, Kuperberg, Larsen, and Propp. Time permitting, we’ll also see what domino tilings have to do with the Arctic Circle. The talk will be accessible to all
undergraduates. No prior knowledge of tilings will be assumed.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9pb5t1jrgblpabtkesl4i9c4kg","2008-08-28 10:19:21","2008-09-08 11:15:41"
"319","22","Financial risk in the ""real"" world","2008-09-18 15:00:00",NULL,"HA 330","Albert Hopping",,"Progress Energy",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/091808.pdf","Value at Risk (VaR) is a benchmark for financial risk, but what does it mean and how do we find it? We’ll discuss commodities and their financial risk with a focus on energy markets. We’ll also look at the practical issues behind calculating VaR for multiple commodities. Depending on audience questions, topics discussed may include forward markets, futures markets, options, implied volatility, Black-Scholes model, Delta, the energy industry in general, GBM, correlations, credit risk, margin accounts, MATLAB, Excel, and statistical distributions.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/093c21kqdqe2jm46bipkj7070s","2008-08-28 10:20:12","2008-09-12 09:00:10"
"320","22","Making the Grad School decision","2008-09-25 15:00:00",NULL,"HA 330","Sandra Paur","http://www4.ncsu.edu/~sopaur","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/092508.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/er5a039qed2et9ml89mpejto5c","2008-08-28 10:21:11","2008-09-08 11:16:39"
"321","22","How the Talmud Divides an Estate Among Creditors","2008-10-02 15:00:00",NULL,"HA 330","Steve Schecter","http://www4.ncsu.edu/~schecter","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/100208.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6vummdngk8ob3dg2q15g2oaj50","2008-08-28 10:22:06","2008-09-08 11:32:02"
"322","22","Computational Engineering and Science at the US Army Corps of Engineers","2008-10-16 15:00:00",NULL,"HA 330","Owen Eslinger",,"US Army Engineer Research and Development Center",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/101608.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7p9bahd5447migcmgi6l529md0","2008-08-28 10:23:00","2008-10-08 14:46:38"
"323","22","The mathematics of voting","2008-10-30 15:00:00",NULL,"HA 330","Molly Fenn",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/103008.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q6j20fojnluj55c8i6hpu71d0c","2008-08-28 10:24:29","2008-10-22 15:55:46"
"324","22","A Modeling Study of Idiopathic Intracranial Hypertension","2008-10-23 15:00:00",NULL,"HA 107  (Note the unusual room!)","Jesse Stimpson",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/102308.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ih8blcipl3v7dlu3mbd7unlia0","2008-08-28 10:25:16","2008-10-15 11:49:36"
"325","22","Buffon's noodle and the Monte Carlo method","2008-11-06 15:00:00",NULL,"HA 330","Drew Armstrong",,"University of Minnesota",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/110608.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6ljq47ng09be5gahb546k56fgc","2008-08-28 10:36:40","2008-10-29 08:58:57"
"326","22","Sports Ranking and Game Prediction, Google style","2008-11-13 15:00:00",NULL,"HA 330","Anjela Govan",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/111308.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i8ncof095uh75jtgom50tef1qo","2008-08-28 10:37:35","2008-09-08 11:33:17"
"327","22","Can you say something about solutions without finding them?","2008-11-20 15:00:00",NULL,"HA 330","Hoon Hong","http://www4.ncsu.edu/~hong","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2008/112008.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m3kc4s3qd7u4o2n7lgd1jni3j0","2008-08-28 10:38:19","2008-11-17 11:00:31"
"328","22","Math Movie Nite (Afternoon)","2008-12-04 15:00:00",NULL,"HA 330",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g4dvmqvirmjmel84n0plbj2h8g","2008-08-28 10:39:59","2008-09-25 14:38:44"
"329","4","Traveling wave solutions for a model of liquid-vapor phase transition","2008-09-17 15:00:00",NULL,"HA 330","Xiao-Biao Lin","http://www4.ncsu.edu/~xblin","NC State",,,"We will discuss traveling wave solutions for dynamical flows involving liquid-vapor phase transition. The model is a coupled system of viscous conservation laws and a reaction-diffusion equation. Sufficient and necessary conditions for the existence of four types of traveling waves will be given: (1) liquefaction waves; (2) evaporation waves; (3) eollapsing waves; (4) explosion waves.
This is joint work with Haitao Fan, Georgetown University.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qq7jkq5sgpff9d5d6mk2cg1cm0","2008-08-28 15:07:12","2008-09-15 13:49:54"
"330","9","Mechanics of tissue dynamics","2008-08-28 15:00:00",NULL,"Williams 2312","Sharon Lubkin","http://www4.ncsu.edu/~lubkin","NC State",,"http://www.ncsu.edu/biomath/abstracts/lubkinAbstract.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ggn2s5lo9rn29g6s4evn63mdss","2008-08-28 15:25:14",NULL
"331","9","Getting to personalized vascular medicine: Development of patient specific boundary conditions for hemodynamic analysis","2008-09-04 15:00:00",NULL,"WMS 2312","Brooke Steele","http://www.bme.ncsu.edu/directory/bio.php?userid=bnsteel&Group=FA&Images=Yes","Department of Biomedical Engineering","Program of biomathematics","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0qi7tjcr16pc19mcmuft6u263s","2008-08-29 12:09:15","2008-08-29 12:16:56"
"332","9","Adding a Random Walk in Carrying Capacity to a Surplus Production Model","2008-09-11 15:00:00",NULL,"WMS 2312","Michael Robert and Becky Lyzinski",,"NC State Biomath Graduate Students","Biomathematics Program","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2v0fjq0o0srkvs994ffubfveu8","2008-08-29 12:15:14","2008-09-08 13:47:23"
"333","9","TBA","2008-09-18 15:00:00",NULL,"WMS 2312","Daniela Valdez-Jasso",,"NC State Biomath Graduate Student","Biomathematics Program","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5k0sefp5a57bf9u0h8li4hbnlk","2008-08-29 12:19:19","2008-09-15 13:49:30"
"334","9","Heart rate regulation: A model assessment","2008-10-02 15:00:00",NULL,"WMS 2312","April Alston",,"Applied Math Graduate Student","Biomathematics Program","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lgnopkbmkh74oa3b38hl0rvnn8","2008-08-29 12:20:39","2008-09-26 17:45:25"
"335","9","TBA","2008-10-16 15:00:00",NULL,"WMS 2312","Judith Canner",,"Biomath Graduate Student","Biomathematics Program","http://www.ncsu/edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mida1tkhouchbo5p78180vi39c","2008-08-29 12:22:37","2008-09-26 17:49:44"
"337","9","Analysis of a Mathematical Model for the First-Pass Dynamics of Antibiotics Acting on the Cardiovascular System","2008-11-13 15:00:00",NULL,"WMS 2312","Nate Wanner and Kathleen Holm",,"Biomath Graduate Students","Biomathematics Program","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2fq92nf5j7b57khvoveh1pg0mc","2008-08-29 15:05:44","2008-11-10 12:15:49"
"338","9","The Effects of Population Mixing on Pandemic Influenza in Portland","2008-11-20 15:00:00",NULL,"WMS 2312","Danielle Robins",,"Biomath Graduate Student","Biomathematics Program","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/82oe6joutqq7stfdrslmo6jqno","2008-08-29 15:06:45","2008-11-18 17:53:20"
"339","9","Modeling the spread of West Nile Virus in a Population of Horses","2008-12-04 15:00:00",NULL,"WMS 2312","Suzy Harvey",,"Biomath Graduate Student","Biomathematics Graduate Program","http://www.ncsu.edu/biomath/seminars.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/of6c3r3kh01iqrcdsrmtpuonc8","2008-08-29 15:07:44","2008-12-03 15:11:06"
"340","4","Songbirds and synfire chains","2008-10-17 15:00:00",NULL,"HA 325","Henry Greenside","http://www.phy.duke.edu/~hsg","Physics Department, Duke University","Steve Schecter",,"Many species of songbirds do not sing instinctively but learn their songs by a process of auditory-guided vocal learning that starts with a kind of babbling that converges over several months and through tens of thousands of iterations to a highly precise adult song. How the neural circuitry of the songbird brain learns, generates, and recognizes temporal sequences related to song are important questions for neurobiologists and also interest an increasing number of nonlinear dynamics researchers. I will discuss some of the interesting questions posed by recent experiments on songbirds, especially in regard to extremely sparse neuronal firing associated with song production. I will then discuss a theoretical model known as a synfire chain that my group [1] and others have invoked and analyzed to explain some features of the experimental data.

[1] ""Stable Propagation of a Burst Through a One-Dimensional Homogeneous Excitatory Chain Model of Songbird Nucleus HVC"", Meng-Ru Li and Henry Greenside, Physical Review E 74:011918 (2006).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/08alr5rrsbbt5s5ecfermadeho","2008-09-02 16:54:45","2008-09-03 14:36:32"
"341","1","The chaotic evolution of Newton's univers","2008-10-13 16:00:00",NULL,"HA 307","Donald Saari","http://www.math.uci.edu/~dsaari","University of California-Irvine",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/b7mq8aedgh4fk536r6e40i43ng","2008-09-03 09:27:04","2008-10-11 15:22:55"
"342","9","TBA","2008-11-06 15:00:00",NULL,"WMS 2312","Mikio Aoi",,"Biomath Graduate Student","Biomath Graduate Program",NULL,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uukt75rojokicvdmej5m4mpckc","2008-09-03 10:59:11",NULL
"343","8","Symmetric Groebner Bases","2008-10-15 15:00:00",NULL,"HA 335","Christopher Hillar","http://www.math.tamu.edu/~chillar/","Texas A&M University","Seth Sullivan",,"In the study of biological, chemical, and statistical models, 
one motivating problem is to determine the algebraic relations between 
experimental measurements.  In this regard, Sturmfels has asked whether, 
up to symmetry, there are finitely many of them that generate the others.  
We discuss some of the mathematics underlying this problem.  Let R be the 
polynomial ring K[X] over a field K in infinitely many variables X = 
{x_1,x_2,...}.  A symmetric ideal I is an ideal that is invariant under 
the natural action of the infinite symmetric group G.  It turns out that 
such ideals are finitely generated as modules over the group algebra K[X].  
We discuss this result and also a recent explicit algorithm to find 
Groebner bases for symmetric ideals in R.  This allows for symbolic 
computation in a new class of rings; in particular, solving the ideal 
membership problem for symmetric ideals of R.  (Joint with Matthias 
Aschenbrenner).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lcsn46jql9acsfavr24jpev86k","2008-09-04 13:33:48","2008-10-15 11:35:15"
"344","6","Geometric and Urban Modeling by L1 Splines","2008-09-30 15:00:00",NULL,"HA 330","John Lavery",,"Mathematics Division, Army Research Office","NA Seminar",,"
A new class of piecewise polynomial splines, called L1 splines, that are free of the extraneous oscillation seen in conventional splines and that preserve the shape of irregularly spaced, error-rich data has arisen. The theoretical framework for L1 splines is based on geometric programming for minimization of a spline functional involving the L1 norm rather than the conventional L2 norm. Algorithms for L1 splines are adaptions of linear and nonlinear programming
algorithms. Non-iterative domain decomposition can be used with these algorithms. Computational results for geometric models and for urban
terrain are presented. In these results, one sees that changing the conventional square of the L2 norm to the L1 norm has unexpectedly large
positive influence on shape preservation. Opportunities for use of L1 splines combined geometric-mechanical modeling, image compression and other areas are outlined. 
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/abpfm5be8qilb945a049ah43fc","2008-09-05 17:30:11","2008-09-05 17:33:26"
"345","14","Departmental Tea and Cookies","2008-09-10 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i5qbsai6jel92la4d27q1smil8","2008-09-08 11:37:53",NULL
"346","8","Finiteness Theorems in Algebraic Statistics","2008-11-12 15:00:00",NULL,"HA 335","Seth Sullivant",,"NC State",,,"I will describe a range of new finiteness results for
statistical models, in particular, results which say that, up to symmetry,
many models in random variables with state space ""tending to infinity""
have finite algebraic descriptions. The focus will be on applications of
these ideas to Markov bases (that is, generating sets of toric ideals),
but the techniques apply to many other statistical models. The results
follow from studying polynomial rings in infinitely many indeterminates
under the action of the infinite symmetric group, which leads to a theory
that is of independent interest.  I will focus on the connections of the
theory to symbolic computation (in particular, the description of a
suitable notion of a finite Groebner basis in this infinite setting) with
the statistical problems serving as motivation.  This is joint work with
Chris Hillar.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3osaei7hbgc431emssuvl5hpjc","2008-09-08 15:24:52","2008-10-28 12:09:20"
"347","23","Introduction to Matlab","2008-09-12 15:00:00",NULL,"HA 330","Adam Attarian","http://www4.ncsu.edu/~arattari/","NC State Mathematics Graduate Student",,"http://www4.ncsu.edu/~arattari/papers/matlab.pdf","Matlab topics including optimization, ODE solvers, plotting
and visualization, and exporting figures in formats appropriate
for papers and presentations.  This will include both some basic
Matlab for folks just getting started as well as more advanced topics such as changing fonts in figures, adding Latex fonts, and changing linewidths.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u895vqifpm6cunr7qvou9etv14","2008-09-09 18:04:14","2008-09-09 18:08:26"
"349","21","Scope 2008","2008-10-10 16:00:00","2008-10-11 19:00:00","Centennial and Main Campus",,,,,"http://www.pams.ncsu.edu/weekend/index.php","Scope Academy 2008, featuring a keynote lecture by Donald Saari,  Distinguished Professor of Mathematics and Economics and director of  the Institute for Mathematical Behavioral Sciences at the University  of California-Irvine, on Chaotic Elections! A Mathematician Looks at Voting. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8vu9tblc4k9amadupu6n6ai87g","2008-09-10 16:34:08","2008-09-11 14:34:30"
"350","21","American Mathematical Society Spring 2009 Southeastern Sectional Meeting","2009-04-04 08:00:00","2009-04-05 17:00:00","Withers and Riddick Hall",,,,,"http://www.ams.org/amsmtgs/2155_program.html",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9lsehjoij5b9j6t2il9li4inok","2008-09-10 16:42:43","2008-09-22 10:55:12"
"351","6","Numerical Implementation of the Asymptotic Boundary Conditions for Steadily Propagating 2D Solitons of Boussinesq Equation","2008-10-30 15:00:00",NULL,"HA 335","Christo Christov","http://www.louisiana.edu/Academic/Sciences/MATH/faculty/cic6380.html","Mathematics Department, University of Louisiana at Lafayette","Alina Chertock",,"The Boussinesq equation (BE) was the first equation that was derived for surface waves in shallow fluid layer when both nonlinearity and dispersion were taken into account. BE appears also in a modeling elastic rods and shells. In a coordinate frame moving with the center of the propagating wave, BE reduces to the Korteweg-De Vries equation (KdVE) which is widely studied in 1D, especially in connection with solitary waves and solitons. At the same time, results for the 2D localized solutions of BE (or KdVE) cannot be found, which justifies a deeper look into the problem.

Unlike the 1D case, where analytical one- and two-soliton solutions can be obtained for some of the limiting cases of BE, none of the well known techniques (such as Hirota bilinear transformation, Backlund transformation, inverse scattering) are available in 2D which leaves numerical and semi-analytical techniques as the only possible tools for attacking the problem. In the present talk, the issues to be overcome for obtaining accurate difference solution are discussed: the bifurcation nature of the localized solution; and the proper implementation of the asymptotic boundary conditions. In 2D, the decay of the profile at infinity is second order algebraic which is much slower in comparison with the exponential decay in 1D. This imposes more demanding requirements on the approximation on top of the fact that a.b.c.'s are nonlocal as well: involving the two different partial derivatives of the solution.

Results are presented for the 2D shapes for different values of the governing parameters and for different phase speeds of the solitons. For validation, the obtained shapes are compared to the results of an asymptotic semi-numerical solution for small phase speeds, and the results are in excellent agreement.


",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6dleah2eri6a0b75b8agje9bf4","2008-09-11 12:30:41","2008-10-08 09:18:29"
"352","14","Departmental Tea and Cookies","2008-09-17 15:45:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fg48qn881i9p7rds7p0vcr9hu4","2008-09-16 09:30:50","2008-09-16 09:31:16"
"353","24","Pizza and Game Night - RSVP jrstaple@ncsu.edu","2008-09-29 19:00:00",NULL,"Talley Student Center room 3118",,,,,,"Mathematics department graduate students, faculty, and staff as well as friends and family are invited. RSVP by September 25th by emailing Rob Stapleton at jrstaple@ncsu.edu.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/03nob0ktc0vfmrvv7e9barg7ls","2008-09-18 13:10:14","2008-09-22 14:50:12"
"354","23","Fundamentals of Latex","2008-09-19 15:00:00",NULL,"HA 330","Amanda Criner",,"NC State Mathematics Graduate Student",,,"This will include discussion regarding the instillation of Latex on your own machine as well as various typesetting commands and strategies including the incorporation of figures in your documents.  The presentation with thus contain topics of interest for both beginning Latex folks and those interested in some of the more detailed points.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ps2s5idjkvh20dvgeon1ekutp4","2008-09-18 14:04:20",NULL
"355","19","Geometric Invariants in Computer Vision","2008-09-23 15:00:00",NULL,"HA 335","Katie Iwancio",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e9niqqqd9afrmev38l7g4nklq0","2008-09-22 11:30:35",NULL
"356","14","Departmental Tea and Cookies","2008-09-24 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mdopeqk9lm0hfof2cks800i8jo","2008-09-23 12:24:05",NULL
"357","23","Fundamentals of Latex: Part II","2008-09-26 15:00:00",NULL,"HA 330","James Holbert",,"NC State",,,"This will include discussion about how to create tables and figures and incorporate figures into Latex. The presentation with contain topics of interest for both beginning Latex folks and those interested in some of the more detailed points.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mdbcmjt59tqsd9j948agdn68n0","2008-09-25 13:32:17","2008-09-25 13:37:08"
"359","6","COUPLED GROUNDWATER FLOW AND HEAT TRANSPORT FOR LARGE-SCALE REMOTE SENSING STUDIES","2008-10-14 15:00:00",NULL,"HA 330","Owen Eslinger",,"US Army Engineer Research and Development Center","Tim Kelley",,"n an effort to improve synthetic thermal imagery for remote sensing
technologies, a suite of closely coupled numerical simulators has been
developed. This computational testbed includes thermal and moisture
transport finite element models, coupled with solar and vegetation
models. It is well suited for simulations of specific scenarios, which
otherwise might be difficult and time consuming to reproduce in the
field. This talk will focus on the code coupling and challenges
encountered with large-scale simulations.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eekr2vdru2on25oim642pi74u4","2008-09-26 09:52:18","2008-10-13 09:54:36"
"360","19","Finite Dimensional A-Infinity Algebra","2008-09-30 15:00:00",NULL,"HA 335","Mike Allocca","http://www4.ncsu.edu/~mpallocc/","NC state Mathematics Graduate Student",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c4u6d06r5vpfj2dg2b7hdmkt6o","2008-09-26 16:11:45","2008-09-29 14:56:44"
"361","9","Markov Models for Accumulating Mutations","2008-10-30 15:00:00",NULL,"WMS 2312","Seth Sullivant",,"Department of Mathematics, NCSU","Biomathematics Program","http://www.ncsu.edu/biomath/seminars.html","http://www.ncsu.edu/biomath/seminars.html",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2n9oml84a7vhb19f57dqungef4","2008-09-26 17:48:56","2008-10-28 18:41:11"
"362","6","A Direct Constrained Optimization Method for Solving the Kohn-Sham Equations","2008-11-13 15:00:00",NULL,"HA 335","Juan C. Meza","http://hpcrd.lbl.gov/~meza/","Larence Berkeley National Laboratory","Ilse Ipsen",,"With the advance of new mathematical algorithms and supercomputers, we can now study many thousand-atom systems, with applications including the study of solar cells for renewable energy, biomedical imaging, and the design of novel materials. One of the most widely used techniques in computational chemistry and material simulations is based on Density functional theory (DFT). Using DFT codes, one can calculate many properties including the electronic structure, the charge density, and the total energy of an electronic system. At the heart of many of these codes, one typically finds a Self Consistent Field (SCF) iteration for solving the resulting Kohn-Sham DFT equations.  In this talk, I will discuss an alternative approach based on an optimization method that minimizes the Kohn-Sham total energy directly.   I will also discuss several acceleration and globalization techniques to improve convergence of the overall method.  Numerical experiments demonstrate that the combination of these approaches is more efficient and robust than SCF alone, which can be shown to fail in certain cases.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i3cqc7ctpure4qhjf5tnn2ing4","2008-09-29 08:56:08","2008-11-03 17:11:50"
"363","14","Departmental Tea and Cookies","2008-10-01 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qd16t1hjt03cpmh71vep0ieud4","2008-09-29 13:23:19",NULL
"364","8","A computer algebra method to infer biological networks","2008-10-22 15:00:00",NULL,"HA 335","Reinhard Laubenbacher","https://www.vbi.vt.edu/faculty/personal_pages/reinhard_laubenbacher","Virginia Tech",,,"This talk will present computer algebra methods for the inference of biochemical networks from time course data. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/df4s06qfpfge22vgula4edbglo","2008-09-30 15:34:48","2008-10-21 20:22:23"
"365","19","Lie algebra multipliers and their properties","2008-10-07 15:00:00",NULL,"HA 335","Louis Levy","http://www4.ncsu.edu/~lalevy/","NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vejtfggvljmpo6ka6ek2b5tmno","2008-10-05 11:14:31",NULL
"366","14","Departmental Tea and Cookies","2008-10-07 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/agtc21oigem6lnofjqph2l668c","2008-10-06 11:42:13",NULL
"367","8","Construction of Chevalley Bases of Lie Algebras","2008-10-29 15:00:00",NULL,"HA 335","Dan Roozemond","http://www.win.tue.nl/~droozemo/home.php","University of Eindhoven","Loek Helminck",,"Lie algebras are often used to study the algebraic groups from which
they originate, but they are interesting objects in their own right as
well. For (almost) every simple Lie algebra there exists a particular
basis with special properties, invented by Chevalley: an extremely
useful tool to study such algebras.

Algorithms exist and have been implemented to, given a Lie algebra in  
some way, compute its Chevalley basis. Unfortunately, these algorithms  
break down in some special cases, in particular over fields of  
characteristic 2 and 3. We give an overview of the difficulties that  
arise in these small characteristics, present some solutions, and show  
how this approach highlights special properties of those Lie algebras.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r769hfrko1tgd7nkhsberu8a64","2008-10-09 09:53:27","2008-10-27 09:54:51"
"368","14","Departmental Tea and Cookies","2008-10-13 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/m326am0dsjs683jrlqgnopjrp8","2008-10-13 15:29:21",NULL
"369","14","Departmental Tea and Cookies","2008-10-15 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kg598df3n4spspr9g4n65ppi2k","2008-10-15 11:33:30",NULL
"370","3,8","Computing the growth series of root and cyclotomic lattices","2009-01-14 15:00:00",NULL,"HA 335","Serkan Hosten","http://math.sfsu.edu/~serkan/","San Francisco State University","Agnes Szanto",,"Given a set of MONOID generators of a lattice, one can define the word length function on the elements of the lattice, and the corresponding generating function also known as the growth series of the lattice. This series is the Hilbert series of atoric algebra. In interesting instances, such as in the case of root lattices A_n, C_n and D_n (where the generators are all roots), or for cyclotomic lattices (where the generators are all roots of unity), this algebra is the coordinate ring of a projective toric variety defined by the convex hull of the generators. Methods from toric Groebner bases and Ehrhart theory gives us a unifying approach to compute the growth series of these root lattices and recover formulae which were first conjectured by Conway--Mallows-Sloane and Baake--Grimm and proved by Conway-Sloane and Bacher--de la Harpe--Venkov. The same methods help us settle conjectures about the growth series of cyclotomic lattices.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/64qhh0d0gbpnhr9vi7nam3s6ls","2008-10-17 09:42:17","2009-01-12 14:02:40"
"371","3","K-theory of the affine Grassmannian","2008-12-05 16:00:00",NULL,"HA 335","Mark Shimozono","http://www.math.vt.edu/people/mshimo/","Virginia Tech",,"http://www4.ncsu.edu/~bnbakalo/seminar/2008/AC120508.pdf","We construct the Schubert basis of the torus-equivariant K-homology of the affine Grassmannian using the K-theoretic NilHecke ring of Kostant and Kumar, in analogy with Peterson's construction in equivariant homology.  In the special case of the affine Grassmannian of SL_n, the K-homology is constructed as a sub Hopf algebra of the ring of symmetric functions, its Schubert basis is characterized and a Pieri rule is given.  This basis consists of inhomogeneous symmetric functions whose highest degree term is the k-Schur function of Lapointe, Lascoux, and Morse. The affine stable Grothendieck polynomials are shown to form the dual basis of K-cohomology of the affine Grassmannian of SL_n, verifying Lam's conjecture.  Our constructions have direct geometric interpretations using Kashiwara's thick affine flag manifold.  This is joint work with Thomas Lam and Anne Schilling.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jljlvdvo6p7t94o13rdpqu8ig8","2008-10-23 13:48:49","2008-11-16 21:38:08"
"372","19","Young Diagrams: combinatorics made easy","2008-10-29 16:00:00",NULL,"HA 274","Katie Liszewski",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g59io0f9a6mi0hpsq5n8udupv4","2008-10-27 12:51:25",NULL
"373","14","Departmental Tea and Cookies","2008-10-29 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6cbo1i3isu2u738dluta3uot0g","2008-10-28 12:45:42",NULL
"374","14","Departmental Tea and Cookies","2008-11-06 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/206pk8t1f7eq5d7bc81rjngg1k","2008-10-31 18:45:43",NULL
"375","14","Departmental Tea and Cookies","2008-11-03 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vkdot4e0mskrcuoosmfbgej1jk","2008-11-03 15:51:49",NULL
"376","14","Redefining Math Education with Clickable Math","2008-11-05 16:30:00",NULL,"HA 307","Robert Lopez",,"Rose-Hulman Institute",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/381ogudl3a5banq6jh0bq77apc","2008-11-05 16:50:59",NULL
"377","14","Departmental Tea and Cookies","2008-11-12 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/c1kf2uhpjh826gd4637irvv638","2008-11-10 15:27:48",NULL
"378","7","An SPDE based Sampling Method","2008-11-17 15:00:00",NULL,"HA330","Dr. Jochen Voss","http://www2.warwick.ac.uk/fac/sci/maths/people/staff/jochen_voss/","Warwick Mathematics Institute, Warwick University, UK","Min Kang",," In many situations it is useful to be able 
 to simulate paths from an SDE conditioned 
 on some interesting event occurring.  But, 
 while simulating an unconditioned SDE is 
 often trivial, simulating paths from a 
 conditioned SDE can be a challenge.  In 
 this talk we present a new sampling method  
 to generate paths from the distribution of 
 a second order SDE under end-point constraints.

 The proposed method works by constructing a 
 fourth-order SPDE which is ergodic and has 
 the distribution of the conditioned SDE as
 its invariant measure (""space"" of the SPDE 
 corresponds to ""time"" of the SDE).  Paths of
 the conditioned SDE can then be found by
 simulating the sampling SPDE until it is 
 close to stationarity and statistical 
 properties of the conditioned SDE can be 
 found by taking ergodic averages of the 
 solution of the SPDE.
   
 In contrast to earlier works (were we used 
 a second order SPDE to sample for the 
 distribution of a conditioned first order  
 SDE) the present method also allows to 
 consider the case where the drift in the
 original SDE does not have a gradient 
 structure.

 We illustrate the method with the help of 
 numerical simulations of the resulting SPDE,
 obtained by using finite elements 
 discretisation.

 (Joint work with Martin Hairer and Andrew   
 Stuart.) ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/igohq5ta51t459p2b5bo9vc2j4","2008-11-11 13:45:47","2008-11-11 13:47:06"
"379","10","Composing the Gene Pool:  Music Made with Genetic Algorithms","2008-11-18 16:30:00",NULL,"Daniels 218","Rodney Waschka",,"NC State",,"http://www.or.ncsu.edu/seminars/documents/ORSeminar-Nov182008.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qdofdg1dse23ab50r1rcjsb7ag","2008-11-16 21:58:12",NULL
"380","14","Departmental Tea and Cookies","2008-11-19 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/c4t18plc9pnqjduqfgjk479p2c","2008-11-17 10:40:40",NULL
"381","6","Entropy based numerical methods for nonlinear PDEs","2009-04-07 15:00:00",NULL,"HA330","Bojan Popov","http://www.math.tamu.edu/~popov/","Texas A & M University","Alina Chertock",,"In this talk we will consider two different numerical methods for solving nonlinear PDEs:
<ol>
<li> A class of L<sub>1</sub>-based minimization methods for solving linear transport equations and stationary Hamilton-Jacobi equations;</li>
<li> Entropy-viscosity methods for nonlinear hyperbolic conservation laws with at least one entropy pair.</li>
</ol>
The above methods are based on second or higher order approximations of the corresponding nonlinear PDE and respect some type of an entropy condition. Theoretical results and numerical examples for the performance of each of the two groups of methods will be presented.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l9upmscjmdh2glalgtoqe6oemk","2008-11-18 10:11:42","2009-03-16 12:44:08"
"382","4","TBA","2008-03-27 15:00:00",NULL,"HA 330","Frederic Lechenault",,"Department of Physics, NC State","Steve Schecter",,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1gkmcivav3imfs1stspq95cddk","2008-11-19 10:16:42",NULL
"383","4","Experimental investigation of equilibration properties in model granular subsystems","2008-12-03 15:00:00",NULL,"HA 330","Frederic Lechenault",,"Department of Physics, NC State","Steve Schecter",,"We experimentally investigate the statistical features of the stationary states reached by two idealized granular liquids able to exchange volume.  The system consists of two binary mixtures of  the same number of soft disks, hence covering the same area, but with different surface properties. The disks sit on a horizontal air table, which provides ultra-low friction at the cell bottom, and are separated by a mobile wall.  Energy is injected into the system by means of an array of randomly activated coil bumpers standing at the edges of the cell. Due to the energy injection, the system acts like a slow liquid and eventually jams at higher packing fraction. We characterize the macroscopic states by studying the motion of the piston.  We find that its average position is different from one half, and is a nonmonotonic function of the overall packing fraction, which reveals the crucial role played by the surface properties in the corresponding density of states.  We then study the bulk statistics of the packing fraction and the dynamics in each subsystem.  We find that the measured quantities do not equilibrate, and become dramatically different as the overall packing fraction is increased beyond the onset of supercooling.  However, the local fluctuations of the packing fraction are uniquely determined by its average, and hence independent of the interaction between disks.  We then focus on the mixing properties of such an assembly.  We characterize mixing by computing the topological entropy of the braids formed by the stationary trajectories of the grains at each pressure.  This quantity is shown to be well defined, very sensitive to onset of supercooling, reflecting the dynamical arrest of the assembly, and to equilibrate in the two subsystems. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cek116m18l13v1e2shc0gon4pc","2008-11-19 10:19:32","2008-12-01 09:38:45"
"386","14","Departmental Tea and Cookies","2008-11-24 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rhs2rclhrnb34f9u9t5rvl70h8","2008-11-19 15:11:03",NULL
"387","21","Honors Program Research Presentation","2008-11-24 14:30:00",NULL,"HA 335","Brittany Boudreaux, Cynthia Breault and Joseph Briggs",,"NC State Math Undergraduate Students",,"http://www.math.ncsu.edu/events/special_events.php","1. Brittany Boudreaux

 Title: Can Thermal Interrogation Reveal Structural Damage?

 Abstract:
 Most modern aero and space structures are composed of composite materials containing significant porosity.  Although
 nondestructive analysis techniques have been developed to
 detect damage in homogeneous materials, little research has
 been done on heterogeneous materials. This NASA-funded project
 aims to use the heat equation to model a thermal interrogation
 method for detecting damage within a porous material.
 Simulations reveal that depending on the accuracy of the
 instruments, damage of a reasonable size can be detected using nondestructive thermal methods. Moreover, the location of the damage can be accurately detected if two heat sensors are used. This minimum size of detectable damage varies depending on the porosity of the material.


 2. Cynthia Breault

 Title: Two Roads Diverged in a Fractal Wood

 Abstract:
 Fractal geometry is a relatively new area of mathematics, only
 introduced within the past 150 years. On the one hand, this is
 a new math and there is much to be explored. We seek to discover and describe new sets that can only be described using fractal geometry. Fractal dimension is a useful tool in identifying and describing these sets. One of the first fractals introduced,
 the middle third Cantor set, is created from a sequence of
 intervals, but has fractal dimension less than that of a line.
 What happens if we take a set that appears similar to the
 Cantor set, but tweak it by taking the absolute value? In a
 particular case, the set is seemingly random but eventually
 yields itself to the pattern and dimension of the middle third
 Cantor set. Is there a way to create a set of this form which
 has dimension less than that of the Cantor set? On the other
 hand, the beauty of these sets cannot be ignored. With the
 help of modern technology, complex and beautiful sets that
 ignore the rules of classic mathematics can be created using
 only a few simple steps. Objects seen in nature that could
 not be fully described using Euclidean geometry can now be
 defined using simple, recursive methods. Small changes to
 the algorithms can produce substantial and striking results.


 3. Joseph Briggs

 Title: An Integral Projection Model Analysis for an
 Endangered Plant

 Abstract:
 I use an integral projection model (IPM) to analyze the
 population dynamics of blowout penstemon (Penstemon haydenii).  In Nebraska this endangered plant naturally occurs in
 ""blowouts"", which are sparsely vegetated depressions in
 active sand dunes created by wind erosion. I estimated size
 dependent survival, growth, and fecundity, and density
 dependent recruitment probability from a large data set
 spanning 13 blowout sites in western Nebraska. For this
 model, there is an asymptotic population and stage structure,
 which is independent of the nonzero initial population and
 stage structure; this is observed numerically and can be proved
 mathematically.  Bootstrap analysis is used to compare the
 predicted population of the 13 blowout sites to the actual
 population.  Under certain initial population conditions,
 a ""transient dip"" is observed which poses an extinction risk
 as the population suddenly drops before approaching its
 asymptotic population state.  Global perturbation analysis
 is used to determine the effects of underlying parameters
 on the asymptotic population and on the transient dip.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/uuru288dd3tturcu889245amig","2008-11-19 19:53:47","2008-11-24 10:36:49"
"388","21","69th Annual William Lowell Putnam Math Competition","2008-12-06 10:00:00","2008-12-06 13:00:00","HA 201",,,,,"http://www.math.ncsu.edu/events/special_events.php","The highest scoring NCSU student in the Putnam receives a cash prize. Walk-in registration starts 15 minutes before the competition. For more information or to obtain practice problems, contact Dr. Lin at xblin@math.ncsu.edu",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/14vpfpm96o31jpbb578p9s8cm4","2008-11-19 19:57:30","2008-11-19 20:01:48"
"389","21","69th Annual William Lowell Putnam Math Competition","2008-12-06 15:00:00","2008-12-06 18:00:00","HA 201",,,,,"http://www.math.ncsu.edu/events/special_events.php","The highest scoring NCSU student in the Putnam receives a cash prize. Walk-in registration starts 15 minutes before the competition. For more information or to obtain practice problems, contact Dr. Lin at  xblin@math.ncsu.edu",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i91i36vc7pggapj4jctph13sd8","2008-11-19 19:59:06","2008-11-19 20:01:59"
"390","14","Departmental Tea and Cookies","2008-12-04 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/aev35c6fdh27tbgataihn2e6co","2008-11-24 10:11:21","2008-12-02 11:35:01"
"391","7","Fractional Levy Ornstein-Uhlenbeck Stochastic Volatility Models","2008-12-05 13:30:00",NULL,"Fox 304","Dr. Jaya Bishwal","http://www.math.uncc.edu/~jpbishwa/","University of North Carolina, Charlotte","Min Kang",,"We account for the two stylized facts in 
financial markets: long memory and jumps. 
The stock price process has jumps and the 
stochastic volatility process has long 
memory and jumps. Long memory in volatility 
occurs when the volatility shocks decay 
slowly and this dates back to Engle (1993).
Models driven by fractional Brownian motion
contain long memory. Fractional Levy process 
is a generalization of fractional Brownian 
motion to include jumps. If the Levy process
is of finite activity, then the corresponding
fractional Levy process is of finite variation.
In the case when the Levy process is not of
finite activity, the corresponding fractional
Levy process is not a semimartingale. By 
replacing the Brownain motion with fractional 
Levy process in the classical Ornstein-Uhlenbeck
process one obtains the fractional Levy-
Ornstein-Uhlenbeck (FLOU) process. Thus the 
model generalizes Barndorff-Neilsen and Shephard
stochastic volatility model. Stochastic 
volatility being not observed, estimation
of the parameters in the FLOU process based 
on stock price data is a hard problem. We suggest
quasi-maximum likelihood estimators for the parameters of a FIECOGARCH (fractionally
integrated exponential continuous time
generalized autoregressive conditional 
heteroscedastic) process based on equally 
spaced observations and randomly spaced
observations. First we study the finite 
activity case: compound Poisson FIECOGARCH
process and study the asymptotic behavior 
of the quasi maximum likelihood estimator. 
Then we study the infinite activity case: Ornstein-Uhlenbeck-Gamma process, a pure 
jump FLOU process. Then using the fact that the 
increments of a general FIECOGARCH process are 
strongly mixing with an exponential rate, we
show that the resulting estimators are 
consistent and asymptotically normal. Parameter estimation in short memory Heston model is still 
a standing hard problem. We study minimum 
contrast estimation of the mean reversion 
speed parameter of the volatility process with
high frequency data using moment matching and 
study the asymptotic behavior of estimators. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ocur73jsg6d53fta0h71c5l1e0","2008-11-24 16:10:51","2008-12-02 17:24:29"
"393","11","Fractional Levy Ornstein-Uhlenbeck Stochastic Volatility Models","2008-12-05 13:30:00",NULL,"Fox 304","Dr. Jaya Bishwal","http://www.math.uncc.edu/~jpbishwa/","University of North Carolina, Charlotte","Tao Pang",,"We account for the two stylized facts in financial markets: long memory and jumps. 
The stock price process has jumps and the 
stochastic volatility process has long 
memory and jumps. Long memory in volatility 
occurs when the volatility shocks decay 
slowly and this dates back to Engle (1993).
Models driven by fractional Brownian motion
contain long memory. Fractional Levy process 
is a generalization of fractional Brownian 
motion to include jumps. If the Levy process
is of finite activity, then the corresponding
fractional Levy process is of finite variation.
In the case when the Levy process is not of
finite activity, the corresponding fractional
Levy process is not a semimartingale. By 
replacing the Brownain motion with fractional 
Levy process in the classical Ornstein-Uhlenbeck
process one obtains the fractional Levy-
Ornstein-Uhlenbeck (FLOU) process. Thus the 
model generalizes Barndorff-Neilsen and Shephard
stochastic volatility model. Stochastic 
volatility being not observed, estimation
of the parameters in the FLOU process based 
on stock price data is a hard problem. We suggest
quasi-maximum likelihood estimators for the parameters of a FIECOGARCH (fractionally
integrated exponential continuous time
generalized autoregressive conditional 
heteroscedastic) process based on equally 
spaced observations and randomly spaced
observations. First we study the finite 
activity case: compound Poisson FIECOGARCH
process and study the asymptotic behavior 
of the quasi maximum likelihood estimator. 
Then we study the infinite activity case: Ornstein-Uhlenbeck-Gamma process, a pure 
jump FLOU process. Then using the fact that the 
increments of a general FIECOGARCH process are 
strongly mixing with an exponential rate, we
show that the resulting estimators are 
consistent and asymptotically normal. Parameter estimation in short memory Heston model is still 
a standing hard problem. We study minimum 
contrast estimation of the mean reversion 
speed parameter of the volatility process with
high frequency data using moment matching and 
study the asymptotic behavior of estimators. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vjkrmcee24sss7hiplkoa8d4d4","2008-12-02 17:26:54",NULL
"394","3","Polytopes and Clique Replacements","2009-01-30 16:00:00",NULL,"HA 335","Jed Mihalisin","http://www.jedsmath.com/","Meredith College",,," I'll introduce the definitions and some basic results about convex polytopes and then describe the Gale transform. This transform is the basis for a new operation, called clique replacement. After proving that all polytopes of a fixed dimension and number of facets are connected by a sequence of clique replacements, I'll discuss some issues, some open questions and possible uses for the operation.
This talk should be accessible to a broad audience.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r44njibk6sauec4a5ileho9m5c","2008-12-08 12:23:03","2009-01-26 10:41:06"
"395","14","Departmental Tea and Cookies","2008-12-09 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/d8p35ei2j2eg2bpots30ueqp8c","2008-12-08 14:23:02",NULL
"397","3","Quantum Groups Defined over Commutative Rings","2009-01-09 16:00:00",NULL,"HA 335","Ben Cox",,"College of Charleston",,"http://www4.ncsu.edu/~bnbakalo/seminar/2009/AC010909.pdf","In this talk we discuss the structure of highest weight
modules for the quantum group U_q(sl(2)) defined over a
commutative ring with particular emphasis on the structure
theory for invariant bilinear forms on these modules.
This is joint work with Thomas J. Enright. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nu00ld1rtlfa4ajoi8to295qgo","2009-01-06 13:57:33","2009-01-06 20:30:35"
"398","3","Computing Geodesic Distances in Tree Space","2009-01-16 16:00:00",NULL,"HA 335","Megan Owen",,"SAMSI and NC State",,"http://www4.ncsu.edu/~bnbakalo/seminar/2009/AC011609.pdf","A phylogenetic tree represents the evolutionary history of a set of
organisms. Billera, Holmes and Vogtmann (2001) constructed a metric space
containing all phylogenetic trees with n leaves, and showed that the
geodesic distance between the points corresponding to trees in this space
is a reasonable inter-tree distance measure. Furthermore, the metric on
this tree space has non-positive curvature, giving several biologically
and statistically interesting implications. I will describe this space and
present an algorithm for computing this geodesic distance between two
phylogenetic trees. In doing so, I present a combinatorial framework in
which the possible shortest paths between two trees can be represented as
a partially ordered set.  The resulting algorithm appears to be the best
available to date.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/34b8gm172j76bq1tgiihpslcmc","2009-01-08 07:27:25","2009-01-13 17:05:59"
"399","22","Regular Polytopes and Tessellations (Why life is more interesting in low dimension)","2009-01-15 15:00:00",NULL,"HA 330","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/011509.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qrsm3j549ecr62tu7f94arfplo","2009-01-08 16:34:51","2009-01-09 08:33:31"
"400","22","The abc conjecture","2009-01-22 15:00:00",NULL,"HA 330","Alina Duca",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/012209.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ahe24kg6u8i9bs7h7bvt1mj74s","2009-01-09 08:35:16","2009-01-21 10:06:33"
"401","22","Ehrhart Theory: Counting points for fun and profit","2009-01-29 15:00:00",NULL,"HA 330","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/012909.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3o4m60aig3p5k9avo0q91imdqo","2009-01-09 08:36:04","2009-01-26 10:42:15"
"402","22","Binomial Coefficients and Beyond","2009-02-05 15:00:00",NULL,"HA 330","Patricia Hersh",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/020509.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n0se3guh0ppka49in43t1t4ulo","2009-01-09 08:36:42","2009-02-02 10:38:39"
"403","22","The Mechanics of Tissue Dynamics","2009-02-12 15:00:00",NULL,"HA 330","Sharon Lubkin","http://www4.ncsu.edu/~lubkin","NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/021209.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/22avfjtsajmtu818m6t8pi8opo","2009-01-09 08:37:11","2009-02-11 13:42:36"
"404","22","The mathematics of sports","2009-02-19 15:00:00",NULL,"HA 330","John Griggs",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oto34g3g9bjgbfjil1783rrsbs","2009-01-09 08:37:31","2009-02-11 13:43:31"
"405","22","Solving Nonlinear Equations","2009-02-26 15:00:00",NULL,"HA 330","C. T. Kelley",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/022609.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g8v90v3gkv0m794jqp2ubjoq98","2009-01-09 08:37:51","2009-02-20 11:48:57"
"406","22","Mechanics with Velocity Constraints","2009-03-12 15:00:00",NULL,"HA 330","Dmitry Zenkov",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/031209.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d8a36i24ec9bd51s07lrqmpqu8","2009-01-09 08:38:14","2009-03-09 10:35:08"
"407","22","The shape of space","2009-03-26 15:00:00",NULL,"HA 330","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/032609.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/im7i7ap65ifbpui1epk0o4ee14","2009-01-09 08:38:31","2009-03-20 14:53:17"
"408","22","Why don't we (usually) faint when we stand up?","2009-04-02 15:00:00",NULL,"HA 330","Mette Olufsen",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/040209.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fcp7bia7qtth2edpo42d20gbg4","2009-01-09 08:38:58","2009-04-01 10:36:48"
"409","22",,"2009-04-16 15:00:00",NULL,"HA 330","Loek Helminck",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4nccpcsbotvdpns3ksjgesd0ik","2009-01-09 08:39:16","2009-01-09 08:42:34"
"410","22","Becoming President with less than 25% of the Vote","2009-03-19 15:00:00",NULL,"HA 330","Chuck Wessell",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2009/031909.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/062497runql0ga2q34d6t6g0oc","2009-01-09 08:39:29","2009-02-20 11:49:57"
"411","6","Computational Models for Biomechanics of the Pericellular Matrix in Articular Cartilage","2009-03-10 15:00:00",NULL,"HA 330","Mansoor Haider","http://www4.ncsu.edu/~mahaider/","Dept of Mathematics, NC State",,,"Articular cartilage contains cells, called chondrocytes, which occupy less than 10% of the tissue volume.  Chondrocyte shape varies with depth and individually (or in small groups) these cells are surrounded by a distinct, narrow tissue region, termed the pericellular matrix (PCM).  Relative to the extracellular matrix (ECM), which is dominated by type-II collagen, the PCM contains mostly type-VI collagen as well as a higher proteoglycan concentration.  Together, the chondrocyte and PCM have been termed a chondron. I will discuss two computational models for biomechanics of the pericellular matrix in articular cartilage.  The first model is based on a finite element method for multiscale modeling of dynamic confined compression of a cartilage layer idealized as a linear biphasic mixture. Simulations support the hypothesized dual role of the PCM as both a protective layer and a mechanical transducer for the cell.  The second model is motivated by a recent experimental technique for in situ imaging of chondron deformation within the ECM of a cylindrical cartilage explant in static unconfined compression.  This technique employs confocal microscopy in conjunction with fluorescent solutes that selectively bind to type-VI collagen.  The resulting data sets provide images of undeformed and deformed cell and chondron shapes within the ECM. Motivated by this application, development of an inverse axisymmetric elastic boundary element method (BEM) will be discussed.  The method extends a previous axisymmetric elastic BEM for boundary value problems to the case of domains with internal interfaces.  Additional improvements include the direct evaluation of strongly singular boundary integrals via series expansions.  The capability of the axisymmetric BEM to model chondron deformation using a small number of 1-d space curves enables rapid simulation of   chondron deformation within the ECM.  Consequently, the forward BEM model can be directly integrated into a Nelder-Meade optimization algorithm for inverse analysis of the experimental data.  The resulting inverse BEM computational model is applied to analyze in situ confocal data from the unconfined compression experiment and to quantify elastic material properties of the chondron.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/apd9lsqq9sfmp100umvq1pmhoc","2009-01-09 10:24:58","2009-03-03 12:48:35"
"412","3","Quasisymmetric Schur functions and refinements of the Littlewood-Richardson Rule","2009-02-13 16:00:00",NULL,"HA 335","Sarah Mason","http://www.davidson.edu/math/mason/","Davidson",,,"We define a new basis for quasisymmetric functions which is obtained from a specialization of nonsymmetric Macdonald polynomials.  We call this the basis of quasisymmetric Schur functions since it partitions the Schur functions in a natural way.  We describe several properties of this basis which are analogous to properties of the Schur functions including a multiplication rule that refines the Littlewood-Richardson Rule.   A modification of this refinement of the Littlewood Richardson rule produces a combinatorial formula for the product of a Demazure character and a Schur function as a positive sum of Demazure characters.  This formula contains the classical Littlewood Richardson Rule as well as a rule for the multiplication of a Schur function with a Schubert polynomial.  This is joint work with Jim Haglund, Kurt Luoto, and Steph Van Willigenburg.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rgge22bb9lpnidmhoj4khtg02k","2009-01-11 18:23:17","2009-02-09 13:12:03"
"413","14","Spring Departmental Meeting","2009-01-13 16:00:00",NULL,"HA 201",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nffv512c2l63qvnuts15p95aj4","2009-01-12 10:57:33",NULL
"414","14","Departmental Tea and Cookies","2009-01-13 15:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pmpn0s69qfjlm03ij0u8ohk6l0","2009-01-12 10:58:14",NULL
"415","3","Induced modules for Affine Lie algebras.","2009-01-23 16:00:00",NULL,"HA 335","Vyacheslav Futorny",,"University of Sao Paulo, Brazil",,,"We will discuss the category of weight modules with nonzero central charge over affine Kac-Moody algebras. A classification of irreducible modules with finite-dimensional weight spaces in this category is known but it remains an open problem in general. The talk will focus on recent progress in this direction  related to the study of the subcategory of induced modules.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hg0n6e9jsg27n43fmh7l2trfu4","2009-01-12 11:55:07","2009-01-13 19:51:10"
"416","2","Stimulus Space Topology and Geometry from Neural Activity","2009-01-20 15:00:00",NULL,"HA 330","Carina Curto",,"Courant Institute, NYU",,,"We construct our understanding of the world solely from neuronal activity generated in our brains. How do we do this? Many studies have investigated how the electrical activity of neurons (action potentials) is related to outside stimuli, and maps of these relationships -- often called receptive fields -- are routinely computed from data collected in neuroscience experiments. Yet how the brain can understand the meaning of this activity, without the dictionary provided by these maps, remains a mystery. I will present some recent results on this question in the context of hippocampal place cells-i.e., neurons in rodent hippocampus whose activity is strongly correlated to the animal's position in space. In particular, we find that topological and geometric features of the animal's physical environment can be derived purely from the activity of hippocampal place cells.  Relating stimulus space topology and geometry to neural activity opens up new opportunities for investigating the connectivity of recurrent networks in the brain.  I will conclude by discussing some current projects along these lines.  This is joint work with Vladimir Itskov (Columbia, CTN). ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/to4rcqocve4v54ov1r2bccgano","2009-01-16 11:16:55","2009-01-20 10:19:15"
"417","2","Deterministic and Stochastic Methods for Biochemical Reaction Systems","2009-01-21 15:00:00",NULL,"HA330","David Anderson",,"Dept. of Mathematics, Univ. of Wisconsin-Madison",,,"The dynamics of biochemical reaction systems can be modeled either deterministically or stochastically. Typically, the equations governing the dynamics of these models are quite complex. Further, there is oftentimes little knowledge about the exact values of the different system parameters, and, worse still, these system parameter values may vary from cell to cell. However, the network structure of a given system induces the corresponding equations (up to parameter values) governing its dynamics. I will show in this talk how this fact may be exploited to infer qualitative properties of large classes of biochemical systems and, most importantly, to learn which properties are independent of the details of the system parameters. I will give results for both stochastically and deterministically modeled systems. I will also discuss some recent work on numerical methods for the simulation of sample paths for stochastically modeled systems. The use of such methods is quickly increasing throughout the biology and biochemistry communities and therefore warrants more careful study.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rhth130rqt6it97bpajcikn2hs","2009-01-16 11:22:08",NULL
"418","2","Mathematical Strategies for Filtering Turbulent Systems: Sparse Observations, Model Errors, and Stochastic Parameter Estimation","2009-01-22 15:00:00",NULL,"HA335","John Harlim",,"Courant Institute, NYU",,,"An important emerging scientific issue in many practical problems ranging from climate and weather prediction to biological science involves the real time filtering and prediction through partial observations of noisy turbulent signals for complex dynamical systems with many degrees of freedom. In this talk, I will present a novel reduced filtering strategy by blending ideas from classical stability analysis for PDE's, Kalman filter, and stochastic models from turbulence theory. Our new strategy is not only computationally attractive but also clarifies many theoretical issues and provides off-line criteria for filtering in many turbulent regimes. The second aspect of the talk deals with model errors in modeling turbulent signals. These errors are often unavoidable due to our inability to justify the physical processes and/or to even numerically resolve some physical processes with current super-computers even if they are well understood. I will describe a radical strategy which produces nontrivial filtering skill with judicious model errors, avoiding the ``catastrophic filter divergence"" exhibited by the perfect model in a fully turbulent regime when observations are sparse. Finally, I will present the ``Nonlinear Extended Kalman Filter"" (NEKF) algorithm that systematically corrects both multiplicative and additive bias in an imperfect model. There are both significantly improved filtering and predictive skill through the NEKF stochastic parameter estimation algorithms provided that these are guided by mathematical theory.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c6imdhk0ruffvofg2qqr90akvk","2009-01-16 11:23:42","2009-01-16 11:24:43"
"419","14","Departmental Tea and Cookies","2009-01-20 14:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9lsmnusmqn4ntq0o2v7avvupks","2009-01-16 11:27:13","2009-01-20 10:17:56"
"420","14","Departmental Tea and Cookies","2009-01-21 14:30:00",NULL," HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/osg4g70kpc28c94nicgbeujpn0","2009-01-16 11:27:45","2009-01-20 10:18:20"
"421","14","Departmental Tea and Cookies","2009-01-22 14:30:00",NULL,"HA 243",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3hcbgs8l6eudo3qhi5a68e18tc","2009-01-16 11:28:40","2009-01-20 10:18:33"
"422","14","Classes Cancelled Today","2009-01-20 08:00:00",NULL,,,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/69agtssusq1itb86qkeldjui3o","2009-01-20 10:17:01",NULL
"423","6","Acceleration of DNA repair by charge transport: stochastic analysis and deterministic models","2009-02-03 15:00:00",NULL,"HA 330","Pak-Wing Fok","http://www.its.caltech.edu/~pakwing/","Caltech",,,"A Charge Transport (CT) mechanism has been proposed in several papers (for example see Yavin et al. PNAS 102 3546 (2005)) to explain the colocalization of Base Excision Repair enzymes to lesions on DNA. The CT mechanism relies on redox reactions of iron-sulfur cofactors on the enzyme. Electrons are released by recently adsorbed enzymes and travel along the DNA. The electrons can scatter back to the enzyme to destabilize it and knock it off the strand, or they can be absorbed by nearby lesions and guanine radicals.

I will first present a stochastic description for the electron dynamics in a discrete model of CT-mediated enzyme kinetics. By calculating the enzyme adsorption/desorption probabilities, I develop an implicit electron Monte Carlo scheme and use it to simulate the build-up of enzyme density along a DNA strand. Then, I will present a Partial Differential Equation (PDE) model for CT-mediated enzyme binding, desorption and redistribution. The model incorporates the effect of finite enzyme copy number, enzyme diffusion along DNA and a mean field description of electron dynamics. By computing the flux of enzymes into a lesion, the search time for an enzyme to find a lesion can be estimated. The results show that the CT mechanism can significantly accelerate the search of repair enzymes. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d3cn930rgq045et0jckd37vu6s","2009-01-22 16:12:50","2009-01-23 10:15:46"
"424","4","Heteroclinic solutions of a singularly perturbed Hamiltonian system","2009-01-28 15:00:00",NULL,"HA 330","Steve Schecter","http://www4.ncsu.edu/~schecter","NC State",,,"We show the existence of heteroclinic solutions for a Hamiltonian system consisting of a pair of second-order ODEs.  Such a solution represents a planar interface between disordered and ordered states in a model for phase interfaces in certain alloys.  The pair of second-order ODEs has a parameter 1/epsilon^2 that represents degree of anisotropy.  In the limit epsilon=0, the slow manifold fails to be normally hyperbolic, due to a pitchfork bifurcation in the fast equation.  Existence of the heteroclinic solution was shown by Sourdis and Fife (2007) using a functional analytic approach.  We show how the same result can be obtained by geometric singular perturbation theory, using blow-up to resolve loss of normal hyperbolicity in the slow manifold.  The advantage of this approach is that it makes the matching of inner and outer solutions more transparent. 

This is joint work with Christos Sourdis (Universidad de Chile).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mhb113htdsplmqhmcep7h1qcdg","2009-01-23 11:09:37",NULL
"425","4","Traveling waves for the Lotka-Volterra system revisited","2009-02-04 15:00:00",NULL,"HA 330","Xiaojie Hou","http://www.uncw.edu/math/math_about_faculty_hou.html","University of North Carolina at Wilmington","Steve Schecter",,"Using a new method of monotone iteration of a pair of smooth lower and upper solutions, the traveling-wave solutions of the classical Lotka-Volterra system are shown to exist for a family of wave speeds. We further derive the explicit value of the minimal (critical) wave speed, as well as the asymptotic rates of the wave solutions at infinities. We also show that the traveling wave corresponding to each wave speed is unique (up to translation). The stability of the traveling-wave solutions with non-critical wave speed is studied by spectral analysis of the linearized operator in an exponentially weighted Banach space.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kl8a7tfse3d73ai7l8q30kao24","2009-01-23 14:18:03","2009-01-23 14:19:42"
"426","3","TBA","2007-02-20 16:00:00",NULL,"HA 335","Patricia Hersh",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jeain0f47n346bakasli24hd6s","2009-01-24 11:04:29",NULL
"427","3","The q=-1 phenomenon via homology concentration","2009-03-13 16:00:00",NULL,"HA 335","Patricia Hersh",,"NC State",,,"Dennis Stanton recently asked for a topological explanation for the fact that the Gaussian polynomial evaluated at -1 yields the number of self-complementary partitions in a rectangle, and for related instances of Stembridge's q=-1 phenomenon. In joint work with Vic Reiner, John Shareshian and Dennis Stanton, we provide such an explanation by introducing chain complexes whose ""face numbers"" are the coefficients in the Gaussian polynomial and whose homology is concentrated in even dimensions. These complexes make sense in more generality, but do not always have such homology concentration. I will discuss a short, topological proof that these complexes are acyclic whenever they are odd dimensional and a Morse matching lemma that is the main ingredient in the aforementioned homology concentration result. Finally, I will describe a related chain complex whose ""face numbers"" count partitions in a 3-dimensional box and whose homology is again concentrated in dimensions all of the same parity, with homology basis indexed by semistandard domino tableaux of rectangular shape. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/26i2raa73ah1ktde766akstgbk","2009-01-24 11:06:39","2009-02-18 20:05:32"
"428","14","Departmental Tea and Cookies","2009-01-27 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/l50pm5ltuedlnipfg0ieqfcf98","2009-01-26 10:34:24","2009-01-26 11:16:38"
"429","19","Some combinatorics associated with the nilpotent variety of a reductive monoid","2009-01-27 15:00:00",NULL,"HA 274","Ryan Therkelsen","http://www4.ncsu.edu/~rtherke/","NC State Mathematics Graduate Student",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gcis147nvptkb6ifa3fkukobs0","2009-01-26 10:52:58",NULL
"430","4","Electrohydrodynamically driven chaotic advection in a translating drop","2009-03-18 15:00:00",NULL,"HA 330","Thomas Ward","http://www.mae.ncsu.edu/directories/faculty/ward.html","Department of Mechanical and Aerospace Engineering, NC State","Steve Schecter",,"A drop translating in the presence of an electric &#64257;eld is studied using a combination of experiments and numerical analysis to determine the underlying mechanism that leads to chaotic advection. The &#64258;ow is a combination of Hadamard-Rybczynski flow and Taylor circulation, due respectively to the translation and the electric &#64257;eld. Two situations will be considered: (i) tilting the electric &#64257;eld relative to the drops' translation motion, and (ii) time-dependent modulation of the electric &#64257;eld. The numerical analysis includes qualitative analysis of the degree of mixing by studying a Poincare map, and quantitative estimates of the largest percentage of drop volume mixed by a single streamline and of the rate of mixing by calculating the largest Lyapunov exponent. Experiments are performed using a castor oil/silicone oil system for the continuous and dispersed phases respectively. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hmlate685a77d8indjkkgm59f8","2009-01-27 12:39:51","2009-03-10 10:01:36"
"431","4","Coarsening: transient and self-similar dynamics in one dimension","2009-04-01 15:00:00",NULL,"HA 330","Tom Witelski","http://fds.duke.edu/db/aas/math/faculty/witelski","Duke University","Steve Schecter",,"Motivated by the dewetting of viscous thin films on hydrophobic substrates, we study models for the coarsening dynamics of interacting localized structures in one dimension. For the thin films problem, lubrication theory yields a Cahn-Hilliard-type governing PDE which describes spinodal dewetting and the subsequent formation of arrays of metastable fluid droplets. The evolution for the masses and positions of the droplets can be reduced to a coarsening dynamical system (CDS) consisting of a set of coupled ODEs and deletion rules. Previous studies have established that the number of drops will follow a statistical scaling law, N(t)=O(t^{-2/5}).  We derive a Lifshitz-Slyozov-Wagner-type (LSW) continuous model for the drop size distribution and compare it with discrete models derived from the CDS. Large deviations from self-similar LSW dynamics are examined on short- to moderate-times and are shown to conform to bounds given by Kohn and Otto. The insight gained can be applied to similar models in image processing and other problems in materials science. 

This is joint work with M.B. Gratton (Northwestern Applied Math).
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ebjpb86nbq1iqok8f9b1bggfb0","2009-01-27 12:45:22","2009-03-20 14:38:07"
"433","23","Making the Perfect Poster","2009-01-30 15:00:00",NULL,"HA 330","Adam Attarian","http://www4.ncsu.edu/~arattari/","NC State","Ralph Smith",,"Posters have become an increasingly common and important medium at conferences and workshops.  Whereas I suspect all of us at some point have created posters by simply ""combining"" talk slides, a quick look around any poster session reveals that successful poster design and construction requires much more thought.

Today's RTM will focus on issues to consider when designing an award winning poster, software that simplifies the process, and details about where to print your posters.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bp8hj74b5u4b1d1qgfgl3lu3t0","2009-01-27 14:01:05",NULL
"434","2","Mirror Symmetry","2009-02-03 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/57uaglnf76ntaaaumugk0ocg7k","2009-01-27 15:40:58","2009-02-02 11:48:58"
"435","8","Geometry of toric patches","2009-03-18 15:00:00",NULL,"HA 335","Luis David Garcia-Puente","http://www.shsu.edu/~ldg005/","Sam Houston State University",,,"Geometric modeling builds computer models for industrial design and manufacture from
basic units, called patches. Many patches, including Bézier curves and surfaces, are
pieces
of toric varieties, which are objects from algebraic geometry. Recently, Bézier
patches have 
been generalized to multi-sided toric patches. While these offer the promise of
greater design 
flexibility, it is not clear whether they possess the desirable properties of Bézier
patches. 
I will discuss work with Frank Sottile and Gheorghe Craciun on elucidating some
geometric properties
of toric patches such as linear precision, self-intersection, and global
deformations of toric patches. 
This work lies in the general context of algebraic geometry applications to
geometric modeling.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0dvbr8b1ourhvg8ml6vk6aeu00","2009-01-27 19:09:15","2009-02-19 10:19:43"
"436","8","Generic Degree of Gröbner Bases of Zero-dimensional Ideals","2009-03-11 15:00:00",NULL,"HA 335","Stephan Ritscher",,"NCSU and Technische Universitat Munchen",,,"Consider a subset {f1, ..., fn} of C[x1, ..., xn] which has finitely 
many common complex solutions.
Let di be the total degree of fi.
Let {g1, ..., gt} be the Groebner basis of {f1, ..., fn} with respect to 
the graded reverse lexicographic ordering.
Let G be the maximum of the total degree of gi and B = (d1-1) + ... + 
(dn-1) + 1.
Daniel Lazard proved that G <= B. Extensitive experiments indicate that 
G = B almost always (generically). This talk sketches an ""almost 
complete"" proof for this observation.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8knu53k12qajbap117184nk4tc","2009-01-30 15:01:42","2009-02-24 20:29:21"
"437","14","Departmental Tea and Cookies","2009-02-03 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/veqd1drqj4brv9khaprn4hj5vg","2009-02-02 10:36:58",NULL
"439","2","Mirror Symmetry","2009-02-10 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vptdprc2peej3itgph3cknfmh8","2009-02-05 16:02:46",NULL
"440","2","Mirror Symmetry","2009-02-17 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3v685n3hpp964mi0e5helre75g","2009-02-05 16:04:00",NULL
"442","2","Mirror Symmetry","2009-03-10 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i2dtrcvmfgbufoqslalfoeu8gg","2009-02-05 16:06:00",NULL
"443","2","Mirror Symmetry","2009-03-17 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6m95b3n2nh0hsmeepvvadllr40","2009-02-05 16:07:48",NULL
"444","2","Mirror Symmetry","2009-03-24 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mtja1mmr2ac14fqr606aaqtrj8","2009-02-05 16:08:19",NULL
"445","2","Mirror Symmetry","2009-03-31 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8ah8veqtenrjfeo7iq8qqenbm8","2009-02-05 16:08:53",NULL
"446","2","Mirror Symmetry","2009-04-07 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8i7vtgmubocngne4j3ms7vtbv4","2009-02-05 16:09:31",NULL
"447","2","Mirror Symmetry","2009-04-14 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6b50k0tm4roarq8oevnapqee3g","2009-02-05 16:10:23",NULL
"448","2","Mirror Symmetry","2009-04-21 13:30:00",NULL,"HA 261",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/59t6cqk39rq0u8c22ao2usjl20","2009-02-05 16:12:01",NULL
"451","14","test","2009-02-06 15:00:00",NULL,,,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/50jnc8gi4130qvd8toejhdl3ks","2009-02-06 17:57:53",NULL
"452","14","Departmental Tea and Cookies","2009-02-11 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/anpn7b0nbdeoludsq9tdu5cv90","2009-02-09 16:25:08",NULL
"453","24","The Fourth Annual MGSA Dessert Contest","2009-02-13 10:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/43rskubne2utu882f4voo3lfio","2009-02-10 09:57:34",NULL
"454","10","Test-and-Prune:  Solving Applied Resource Allocation and Utilization Problems","2009-01-27 16:30:00",NULL,"Daniels 218","Amy Cohn",,"University of Michigan",,"http://www.or.ncsu.edu/seminars/documents/ORSeminar-Jan272009_003.pdf","In this talk, I will present three very different applications (from
manufacturing, healthcare scheduling, and renewable energy sources) that pose three very different mathematical challenges (weak linear programming relaxations, multiple objective criteria, and probabilistic chance constraints). I will then introduce a new algorithm, Test-and- Prune, for solving resource allocation and utilization problems. I will show that through a broad interpretation of the terms ""resource"" and ""utilization"", we can apply this algorithm to solve all three of these seemingly very different problems (and many more).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lia1n51nklko6r9u3k1mg467q0","2009-02-10 10:24:12",NULL
"455","9","Computing geodesic distances in tree space","2009-02-12 15:00:00",NULL,"315 Riddick Hall","Megan Owen","http://www.cam.cornell.edu/~maowen/","SAMSI",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/79epp63c4ir5s39um0g0p9siqs","2009-02-10 10:28:01",NULL
"456","4","Long-time behavior of collisionless plasma","2009-03-20 15:00:00",NULL,"HA 368","Stephen Pankavich","http://www.uta.edu/faculty/stephenp/Stephen_Pankavich.html","University of Texas at Arlington","Steve Schecter",,"The motion of a collisionless plasma - a high-temperature, low-density, ionized gas - is
described by the Vlasov-Maxwell system. In the presence of large velocities, relativistic
corrections are meaningful, and when magnetic effects are neglected, one formally obtains the relativistic Vlasov-Poisson system. Similarly, if one takes the classical limit as the speed of light tends to infinity, one obtains the classical Vlasov-Poisson system. We study the long-time dynamics of these systems, and contrast the behavior for classical versus relativistic velocities and for monocharged (i.e., single species of ion) versus neutral plasma.

This is joint work with Robert Glassey (Indiana) and Jack Schaeffer (Carnegie Mellon).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6ita8k222jgebss2omcdng6np0","2009-02-11 13:58:16","2009-03-10 09:47:42"
"457","14","Departmental Tea and Cookies","2009-02-18 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/90k5e3o0oq1euudf3h6o8kkitk","2009-02-16 10:27:02",NULL
"458","14","Departmental Tea and Cookies","2009-02-25 15:00:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/te4l92jhf9g0gf6ul4dno98du4","2009-02-23 09:31:33",NULL
"459","8","Siphons, primary decomposition, and the Global Attractor Conjecture","2009-04-01 15:00:00",NULL,"HA 335","Anne Shiu",,"UC Berkeley",,,"In a biochemical reaction network, the concentrations of chemical species evolve in time, governed by the polynomial differential equations of mass-action kinetics.   This talk provides an introduction to the algebraic and combinatorial study of chemical reaction network theory.  The nicest networks are the toric dynamical systems, which are those whose steady states are a special kind, called complex balancing steady states. Algebraically, the steady state loci and moduli spaces form toric varieties.  One might ask whether we can characterize the limiting behavior of such systems.  The assertion that a trajectory of such a system converges to a point on the toric variety (rather than a boundary point of the positive orthant) is the content of the Global Attractor Conjecture, which has been open for thirty years. The concept of a ""siphon"" (in the work of D. Angeli, P. De Leenheer, and E. Sontag), or equivalently a ""semi-locking set"" (in the work of D. Anderson), describes the possible zero-coordinates of boundary steady states; understanding their structure has been an important goal in pursuing the conjecture. An algebraic approach to this family of ideas will be presented; in particular, primary decomposition plays a prominent role.

 No prior knowledge of chemical reaction network theory or toric geometry will be assumed.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/inaofktj3im5v5nq92dr3beheg","2009-02-23 19:16:06","2009-03-26 15:33:22"
"460","10","Exact and Inexact Methods for Selecting Views and Indexes for OLAP Performance Improvement","2009-03-10 16:30:00",NULL,"Daniels 218","Zohreh Asgharzadeh Talebi",,,,"http://www.or.ncsu.edu/seminars/documents/ORSeminar-Mar102009.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/abh6nor3t2hdvhp6eadggjfr20","2009-03-09 10:36:42",NULL
"461","10","TBA","2009-03-17 16:30:00",NULL,"Daniels 218","Yu-Min Lin",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/prbnvck1p19rv8o6u65masiun0","2009-03-09 10:37:10","2009-03-16 12:02:55"
"465","9","Avian Point Count Sampling Models and Field Validation","2009-03-12 15:00:00",NULL,"Riddick Hall 315","Ken Pollock",,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2rp18oi3emin0tnndkv2vugor0","2009-03-09 10:48:28",NULL
"466","9","TBA","2009-03-19 15:00:00",NULL,"Riddick Hall 315","TBA",,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6g0kcorbup008h7gibnajo6ags","2009-03-09 10:49:06",NULL
"467","14","Departmental Tea and Cookies","2009-03-11 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5ap19rn558ah89a47hmgn4m0ks","2009-03-10 10:03:10",NULL
"468","6","Stabilized completions of general differential algebraic equations","2009-04-14 15:00:00",NULL,"HA 330","Stephen L. Campbell","http://www4.ncsu.edu/~slc/","Mathematics, NCState",,,"Differential algebraic equations (DAEs) are a natural way to model a wide variety of physical phenomena.  All numerical methods for DAEs must, in some manner, construct a differential equation (ODE) that can be integrated.  Sometimes this is done by determining an ODE on a submanifold and sometimes this is done by building an ODE, called a completion of the DAE,  which includes the DAE solutions.    A number of useful results have been developed which exploit the structure of specific problems.  But the increasing use of composite models drawn from different disciplines means this structure may not be there.  Also a number of control problems do not have a predetermined structure.  Recently there has been a renewed effort to construct stabilized completions of general DAEs strictly in terms of the original equations.  This talk will introduce this problem, discuss  some of the recent results and ongoing investigations, and time permitting some potential applications in control and simulation.

This research is joint work with Prof. Peter Kunkel of the University of Leipzig and Prof. Irfan Okay of Dalton State College. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tjovj9inctmpgpkgejoc247v0c","2009-03-10 11:40:23",NULL
"469","6","Numerical Solution of the Nonlinear Helmholtz Equation","2009-03-17 15:00:00",NULL,"HA 330","Semyon Tsynkov","http://www4.ncsu.edu/~stsynkov/","Math. NCSU","NA seminar",,"The nonlinear Helmholtz equation (NLH) governs the propagation of intense laser light in (transparent) Kerr dielectrics, when the key phenomenon of interest from the standpoint of physics is self-focusing. In the talk, we will  describe a high order finite-difference method for solving the NLH. It allows to compute the solutions also for those cases when the material (optical) characteristics of  the medium are
discontinuous. The method appears particularly efficient for studying  a long-standing important question in nonlinear optics -- the formation of singularity in the solution
when the scattering of light in the medium is assumed predominantly forward (the so-called paraxial approximation). For the first time in the literature, we have been able to obtain bounded regular solutions for those regimes for which  the solution of the paraxial approximation (governed by the nonlinear Schroedinger equation) blows up on finite propagation distances. Moreover, for the case of  subcritical propagation we have obtained solutions in the form of ""narrow"" spatial  
solitons, and have also modeled interactions (""collisions"") between those  solitons.

Joint work with G. Baruch and G. Fibich of Tel Aviv University, Israel.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j3j3nl6cqgr86gcuh48m7ating","2009-03-14 18:45:45",NULL
"470","14","Departmental Tea and Cookies","2009-03-17 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/a2584qjfdc6tnph43kjg3am7po","2009-03-16 12:52:51","2009-03-16 13:14:27"
"471","3","Combinatorial Reciprocity Theorems","2009-04-03 16:00:00",NULL,"HA 335","Matthias Beck",,"San Francisco State University",,,"A common theme of enumerative combinatorics are counting functions given by polynomials that are evaluated at positive integers. For example, one proves in any introductory graph theory course that the number of proper k-colorings of a given graph G is a polynomial in k, the ""chromatic polynomial"" of G. Combinatorial reciprocity theorems give interpretations of these polynomials at negative integers. For example, when we evaluate the chromatic polynomial of G at -1, we obtain (up to a sign) the number of acyclic orientations of G, that is, those orientations of G that do not contain a coherent cycle.

Combinatorics is abundant with polynomials that count something when evaluated at positive integers, and many of these polynomials have a completely different interpretation when evaluated at negative integers. We follow a common thread of chromatic and flow polynomials of graphs, a counting function for magic squares, Ehrhart polynomials enumerating integer points in polytopes, and characteristic polynomials of hyperplane arrangements.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e70o3jvkjb34d4ak3pr2orarr8","2009-03-16 15:27:34","2009-03-30 11:10:50"
"472","21","Reading DNA sequences: Twenty-first century technology with eighteenth century mathematics.","2009-04-04 19:00:00","2009-04-04 20:00:00","Nelson 3400","Michael S. Waterman",,"University of Southern California",,"http://www.ams.org/amsmtgs/2155_abstracts/1048-92-10.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b9t19apiiv5lo0igq8icopgi78","2009-03-18 15:51:27",NULL
"473","10","Hazards with Impulsive Sources: Identification and Control","2009-03-24 16:30:00",NULL,"Daniels 218","Dr. Robert White","http://www4.ncsu.edu/~white/","NC State","Operations Research","http://www.or.ncsu.edu/seminars/documents/ORSeminar-Mar242009.pdf","Given some observations downstream can one determine the location and intensities of point sources of a hazard (pollutant chemical or biological)?
The unknown concentrations are governed by the diffusion-advection partial differential equation. In this study the corresponding algebraic equation is considered. The fixed location problem is considered using reordering, the Schur complement and nonnegative least squares. The variable location problem is attacked using simulated annealing. The complexities of controlling aquatic populations, which are nonlinear, time dependent and have multiple sources, will be illustrated.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3nraeu14crv72kk7ngauknmlak","2009-03-19 10:03:09",NULL
"474","6","BLAS-3 Sparse Householder Reduction to Banded Triangular Form","2009-04-21 15:00:00",NULL,"HA 330","Gary Howell",,"NC State Computer Science","Tim Kelley",,"A matrix can be reduced to triangular banded form by BLAS-3 Householder
transformations.  Deferring matrix updates, a sparse algorithm accesses A
only to extract blocks and to perform right multiplications by a dense matrix X, left multiplications by a dense matrix Y.  For a reduction to a triangular matrix with K nonzero diagonals, X has K columns,
Y has K rows.  Using block Householder transformations gives good stability properties.

The returned banded matrix B grows a K-block at a time. The size of B is constrained by the necessity to fit the accumulated Householder transformations in RAM. As RAM grows in quantity (e.g. commodity nodes with 16 GBytes
of RAM), the Householder reduction becomes useful for increasingly large matrices.

Numeric experiments show that the operations AX and YA are fast and that the returned triangular matrices B contain information about the singular
values of A.  When A is small enough that B can be large, many singular
values of A are shared by B.  Some other applications of the sparse reduction
 are in solving least squares problems, in providing low rank approximations for A, and in producing approximate inverse preconditioners.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0p9o89pbeks821e96h92cegp6k","2009-03-22 14:02:28","2009-03-23 09:54:08"
"475","3","Quantum K theory of Grassmannians","2009-04-24 16:00:00",NULL,"HA 335","Leonardo Mihalcea",,"Duke University",,,"The 3-point, genus 0, Gromov-Witten invariants of a Grassmannian count rational curves of degree d satisfying certain incidence conditions - if the number of curves is expected to be finite. For infinitely many curves, Givental and Lee defined the K-theoretic Gromov-Witten invariants, which compute the sheaf Euler characteristic of the space of rational curves in question, embedded in Kontsevich's moduli space of stable maps. The resulting quantum cohomology theory - the quantum K-theory - encodes the associativity relations satisfied by the K-theoretic Gromov-Witten invariants.

In joint work with Anders Buch we have obtained algorithms to compute explicitly the (equivariant) K-theoretic Gromov-Witten invariants and the 
quantum K-theory algebra. The key fact is the ""quantum=classical"" phenomenon: the K-theoretic Gromov-Witten invariants for Grassmannians are 
equal to structure constants of the ordinary K-theory of certain two-step flag manifolds. This generalizes - and reproves - an earlier result of 
Buch, Kresch and Tamvakis which holds for the ordinary Gromov-Witten invariants.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e5u1rr5evgkn0cdjl8vkk6toks","2009-03-23 11:32:38","2009-04-13 13:00:25"
"476","9","TBA","2009-03-26 15:00:00",NULL,"Riddick Hall 315","Alison Motsinger-Reif",,"NCSU Bioinformatics Research Center",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e6rl7d6225sb6adus6a74abb9g","2009-03-23 12:06:16",NULL
"477","14","Departmental Tea and Cookies","2009-03-25 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/547k30fe61ik11gjkoas3krl8g","2009-03-23 12:41:18",NULL
"478","7","Diffusion in Soft Matter","2009-03-31 15:00:00",NULL,"HA335","Scott McKinley","http://fds.duke.edu/db/aas/math/mckinley","Duke University","Min Kang",,"Stochastic models for diffusion of Brownian particles in soft matter (viscoelastic media) play a central role in polymer dynamics and rheology, microrheology, and medical science. A sufficiently robust class of stochastic processes is required to capture the range of observed anomalous diffusive behavior, in particular transient power law scaling of the mean-squared displacement (MSD) of tracked particles.  We consider the Generalized Langevin Equation characterized by a Prony series approximation to the relaxation kernel, and study in particular this system in its zero mass limit. Such a study reveals a robust class of models which exhibit transient anomalous diffusion while remaining amenable to rigorous analysis. (Joint work with Greg Forest, UNC-Chapel Hill and Lingxing Yao, Utah)",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6rv5u4i53qmd922uutl9d5e54g","2009-03-24 11:54:19",NULL
"479","9","TBA","2009-04-02 15:00:00",NULL,"Riddick 315","Cliburn Chan",,"Duke University Laboratory of Computational Immunology",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5kurgmt3ec1sgsnbfjhqomhd3o","2009-03-30 10:49:01","2009-03-30 10:52:08"
"480","10","TBA","2009-03-31 16:30:00",NULL,"Daniels 218","Zhe Liu",,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4q5pdbaovi3jspm8mq332cjn2k","2009-03-30 10:51:06",NULL
"481","14","Departmental Tea and Cookies","2009-04-01 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p9na33qmgn6ttk9ggj30c92j7k","2009-03-30 14:57:33",NULL
"482","10","First and Second Order Conditions for Stochastic Programming Problems","2009-04-07 16:30:00",NULL,"Daniels 218","Dr. Negash Medhin",,"Mathematics NC State","Operations Research Program",,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j1he37j4dl5d628qlod0cotmao","2009-04-03 14:11:00","2009-04-03 14:11:48"
"483","9","Mathematical models of T cell development and function","2009-04-09 15:00:00",NULL,"Riddick 315","Dr. Stanca Ciupe",,"Duke Univ Laboratory of Computational Immunology","Kevin Gross",,"The immune response to infectious agents involves the presence and maintenance of a large number of T cells with highly variable antigen receptors and functional diversity. In the first part of the talk, we will explain the mechanisms underlying the establishment and maintenance of T cell receptor diversity and T cell population homeostasis using mathematical models and statistical analysis of data from DiGeorge syndrome patients undergoing thymus transplantation. In the second part, we will present the functional properties of the T cells when stimulated by antigen, in our case the Hepatitis B virus. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k1m3tpc2n4ouhiu3l7omjtva94","2009-04-05 20:10:01",NULL
"484","14","Departmental Tea and Cookies","2009-04-16 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/v4c9o1oebi1a0ave14hng8u1eg","2009-04-07 15:47:04","2009-04-08 13:39:37"
"485","3","Invariant theory: old and new","2009-04-17 16:00:00",NULL,"HA 335","Amassa Fauntleroy",,"NC State",,,"This is a report on the recent work of Doran and Kirwan on geometric invariant theory.  This is a 
survey talk, so no background in the area is 
required.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rv6info47dupjqvbtv575pnur8","2009-04-07 16:51:37",NULL
"486","19","Bounding the Multiplier of a Lie Algebra M(L)","2009-04-14 15:00:00",NULL,"HA 274","Lindsey Bosko",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nh249nasoi9lbojkf8nebcudpk","2009-04-13 12:37:44",NULL
"487","14","Overview of the NSF Division of Mathematical Sciences","2009-04-16 15:00:00",NULL,"HA 201","Peter March",,"Division of Mathematical Sciences, National Science Foundation",,,"Overview of the NSF Division of Mathematical Sciences and 
discuss the division’s support of core disciplines, collaborative 
and interdisciplinary activities and other foundation-wide initiatives.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/tm07i1pn602un1nrd0g7hsirls","2009-04-16 10:09:29",NULL
"488","9","TBA","2009-04-23 15:00:00",NULL,"Riddick 315","Hyun Jin Kim",,"Stanford",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u4889vq4eis630ue970c8g16tg","2009-04-19 22:01:02",NULL
"489","19","Representation Theory of U_q(so(2n))","2009-04-21 15:00:00",NULL,"HA 274","Evan Wilson",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cvemdkprfhfitq0t3vg5qq50q0","2009-04-20 10:35:28",NULL
"490","14","Departmental Tea and Cookies","2009-04-20 14:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/j67444cvu8r19ff7mtceq8fteg","2009-04-20 12:09:25",NULL
"491","14","Undergraduate Research Presentation","2009-04-22 14:30:00",NULL,"HA 330","Rachel Gordon, Jeff Olander, and Chelsey Cooley",,"NC State Undergraduate Students",,,"2:30        Rachel Gordon-Wright - Free Granular Surfaces

2:50        Jeff Olander - ODE Modeling of Cartilage Regeneration in a Cell-Seeded Scaffold                 

3:10        Chelsey Cooley - A Novel System for Aggregating Preferences",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s74iobm7jthf7ui7fpj8tblo4c","2009-04-20 12:20:29",NULL
"492","14","Math Awards Day Ceremony","2009-04-22 16:00:00",NULL,"HA 201",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/shdjlgvkbeet0j1ajcd3lldorc","2009-04-20 12:21:13","2009-04-21 11:31:18"
"493","14","Undergraduate Research/Awards Day Tea and Cookies","2009-04-22 15:30:00",NULL,"HA 245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kfldvlho39p5m7ug35rnprlft8","2009-04-20 12:22:30",NULL
"495","14","Undergraduate Research Tea and Cookies","2009-04-23 15:15:00",NULL,"HA245",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lbhj5j5ma4grl4fnblblveljq8","2009-04-20 12:24:36","2009-04-20 12:25:08"
"496","14","Undergraduate Research Presentation","2009-04-23 14:30:00",NULL,"HA 330","Billy Tallis and David Brown",,"NC State Undergraduate Students",,,"2:30   Billy Tallis - Computer Optimization of a Sheet-Beam
Electron Gun
2:50   David Brown - Modeling Heterogeneity in Glioblastoma Multiforme

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ddtin7do85gakj0oc83qc22mt8","2009-04-22 11:55:24","2009-04-22 11:58:13"
"497","3","A Continuum of Partition Statistics","2009-05-20 16:00:00",NULL,"SAS 3282","Nick Loehr",,"Virginia Tech",,,"A well-known partition theorem states that the generating function for partitions by area and number of parts is

$\prod_{i=1}^{\infty} (1-tq^i)^{-1}$.

This talk describes a surprising extension of this result in which the ``number of parts'' statistic is replaced by other statistics parametrized by positive real numbers r. We give a bijective proof of the equidistribution of all these statistics. The proof utilizes various combinatorial constructions including cylindrical lattice paths, Eulerian tours on directed multigraphs, and involutions on oriented trees.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mo8267mbqk1ldredflb2oe3do0","2009-05-18 22:39:17",NULL
"498","14","REU Departmental Tea and Cookies","2009-06-10 14:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/atlcq7etb8b3v5keencjc0rpbo","2009-06-09 21:11:30",NULL
"499","14","Departmental Tea and Cookies (May be postponed to Thurs if furniture not setup)","2009-06-17 14:30:00",NULL,"Math Commons in SAS Hall",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hhf1lq3gqc3t5ih5u122km5nb8","2009-06-16 20:16:38",NULL
"500","14","REU Departmental Tea","2009-06-24 14:30:00",NULL,"Math Commons, 4104",,,,"Financial Math, Math Department & The REU Program",,"The Departmental and Summer REU TEA.  

All REU participants, Math Grad, Faculty & Staff are welcome to come.  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/f2ijnodr91hddj9elvtel6hbjo","2009-06-23 16:23:46",NULL
"502","14","Departmental Tea","2009-07-01 14:30:00",NULL,"SAS  4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p8i5fqmv2c64omo0i2scej1us0","2009-06-30 15:17:47",NULL
"503","14","REU/Departmental Tea","2009-07-08 14:30:00",NULL,"Math Commons, 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ldab8nq0i3m9pmorn6uugvgi7o","2009-07-06 10:57:27",NULL
"504","3","Primary and Other Decompositions of Binomial Ideals","2009-07-30 15:00:00",NULL,"SAS 4201","Thomas Kahle","http://personal-homepages.mis.mpg.de/kahle/","MPI, Leipzig, Germany",,,"In 1996 Eisenbud and Sturmfels published their theory of binomial ideals together with specialized algorithms that had never been implemented. We present refinements of their algorithms together with a reference implementation in Macaulay 2. By using the combinatorial structure of binomial ideals, the speed of common computations like finding the minimal primes or a primary decomposition can be improved significantly. We demonstrate the power of this approach by showing a counterexample to a recent conjecture of Evans/Sturmfels/Uhler.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/msr76f5mi3q2ifoas4ujqad6ug","2009-07-13 14:34:36",NULL
"505","3","Non-crossing pairings","2009-09-10 16:00:00",NULL,"SAS 4201","Cliff Smyth",,"UNC-Greensboro",,,"Let P be a polygon with 2n vertices.  A pairing of P is a set of chords so that each vertex is contained in exactly one chord.  A pairing is non-crossing if no two of its chords cross (i.e. intersect).  Let C be a coloring of P, i.e. a partition of the vertices of P into two color classes. We say that P is compatible with C iff none of its chords has both endpoints in just one color class of C.

Let f(C) be the number of non-crossing pairings compatible with C.  These numbers arise as the moments of the circular operator, an object of  importance in free probability.  They also appear in a number of other combinatorial problems involving trees, paths, tilings, etc.

We'll discuss some interesting polynomial formulas for f on ""balanced colorings"" and some conjectures on maximizing and minimizing f, subject to fixing the number of ""runs"" of the coloring.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oalfmqtdcfsvsk8bujc7g8qsk0","2009-07-14 15:52:41","2009-08-17 21:23:31"
"506","3","Enumeration of the distinct shuffles of permutations","2009-09-18 16:00:00",NULL,"SAS 4201","Camilla Smith",,"Sweet Briar College",,,"A shuffle of two words is a word obtained by concatenating the two original words in either order and then sliding any letters from the second word back past letters of the first word, in such a way that the letters of each original word remain spelled out in their original relative order. Examples of shuffles of the words 1234 and 5678 are, for instance, 15236784 and 51236748. In this talk, I enumerate the distinct shuffles of two permutations of any two lengths, where the permutations are written as words in the letters 1,2,3,...,m and 1,2,3,...,n, respectively.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/opv0pve4a9nicr4r7jfublp200","2009-07-24 09:22:10","2009-08-17 21:50:47"
"507","3","A Geometric Interpretation of the Characteristic Polynomial of  Reflection Arrangements","2009-10-23 16:00:00",NULL,"SAS 4201","Mathias Drton",,"University of Chicago","Seth Sullivant",,"We consider projections of points onto fundamental chambers of finite real reflection groups. Our main result shows that for groups of type $A_n$, $B_n$, and $D_n$, the coefficients of the characteristic polynomial of the reflection arrangement are proportional to the spherical volumes of the sets of points that are projected onto faces of a given dimension. We also provide strong evidence that the same connection holds for the exceptional, and thus all, reflection groups. These results naturally extend those of De Concini and Procesi, Stembridge, and Denham which establish the relationship for 0-dimensional projections. This work is also of interest for the field of order-restricted statistical inference, where projections of random points play an important role.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3fd5bt11l45kicgosaiar53qpo","2009-07-24 09:34:13","2009-10-12 20:31:00"
"508","3","Affine dual equivalence","2009-10-02 16:00:00",NULL,"SAS 4201","Sami Assaf",,"MIT","Patricia Hersh",,"The k-Schur functions were first introduced by Lapointe, Lascoux and Morse in the hopes of refining the expansion of Macdonald polynomials into Schur functions. Recently, an alternative definition for k-Schur functions was given by Lam, Lapointe, Morse, and Shimozono as the weighted generating function of starred strong tableaux. This definition has been shown to correspond to the Schubert basis for the affine Grassmannian and at t=1 it is equivalent to the k-tableaux characterization of Lapointe and Morse. Using this new definition for k-Schur functions, we prove the symmetry and Schur positivity of k-Schur functions combinatorially using the theory of dual equivalence graphs. Central to our proof is our discovery of an analog of dual equivalence for the affine symmetric group. We also make connections between k-Schur functions and both LLT and Macdonald polynomials by comparing the graphs for these functions.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d1bplqoejtaerus1dc3n86h1ts","2009-07-24 11:48:11","2009-08-12 09:57:25"
"509","14","Fall Mathematics Department Meeting","2009-08-20 16:00:00",NULL,"SAS 1102",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kp8h5c7t005f753der0oemgpn8","2009-08-07 12:49:50",NULL
"510","14","Departmental Tea and Cookies","2009-08-20 15:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/cn386uhrina59q4srm0t2spaa0","2009-08-07 12:50:44",NULL
"511","3","Cellular resolutions of monomial ideals and LCM lattices","2009-09-25 16:00:00",NULL,"SAS 4201","Sonja Mapes",,"Duke",,,"In the study of cellular resolutions of monomial ideals it is often useful to consider the LCM lattice of the given monomial ideal.  In particular, it is known that all ideals with isomorphic LCM lattices have isomorphic minimal resolutions.  In this talk I will give the necessary background on free resolutions of monomial ideals and then discuss how studying the parameter space of LCM lattices provides one with new insights into the structure of these resolutions. 

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5a131qnruhn6ps97sov21apb2o","2009-08-13 18:40:24","2009-08-30 20:42:49"
"512","8","Markov degrees of hierarchical models arising from Betti numbers of Stanley-Reisner ideals","2009-11-18 16:30:00",NULL,"SAS 4201","Sonja Petrovic",,"University of Illinois, Chicago","Seth Sullivan",,"There are two seemingly unrelated classical objects associated to a
simplicial complex: a hierarchical model and a Stanley-Reisner ring.
A hierarchical model gives rise to a toric ideal, a relationship that
is a staple of algebraic statistics. The degrees of generators of this
ideal are dubbed ""Markov degrees"" and encode the complexity of the
model.
In turn, a Stanley-Reisner ideal is a monomial ideal whose algebraic
properties are encoded by the combinatorial properties of the complex.
Betti numbers encode ranks of free modules in a minimal free
resolution of the Stanley-Reisner ring, a central object in
commutative algebra.

In this talk, I will introduce all of these concepts, and present a
recent result which explores a first connection between Markov degrees
of the model and Betti numbers of the Stanley-Reisner ideal.
As an application of the main theorem, we recover a result of Froberg
which classifies simplicial complexes with linear resolutions.

This talk is based on joint work with Erik Stokes, preprint available
at      arXiv:0910.1610v1","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/imdealmdasgi7s7hrfsv7fsd3c","2009-08-14 17:49:59","2009-11-06 13:32:37"
"514","6","Uncertainty Quantification Methods Enabling Credible Simulation","2009-11-05 16:00:00",NULL,"Burlington Labs","Brian Adams",,"Sandia National Laboratories","NA Seminar; NE Department",,"To be credible, computational models must be verified in their software implementation, validated with data, and deliver a best estimate of performance, together with its degree of variability or uncertainty.  Estimates of variability or uncertainty require enhancing science-based simulations with non-deterministic analysis methods accounting for both aleatory (inherent/probabilistic) and epistemic (lack-of-knowledge) uncertainties.

In this talk, I will offer an accessible introduction to uncertainty quantification (UQ) methods that assess model output responses as a function of input parameter uncertainty.  These typically yield information on response means, standard deviations, level probabilities, reliability indices, or belief/plausibility bounds.  I will survey such forward uncertainty propagation approaches as Latin hypercube sampling, reliability methods, and polynomial chaos/stochastic collocation.  These can treat simulations as ""black boxes,"" assessing them without intrusive code modification.  I will demonstrate how advanced UQ methods employ a mix of probability, nonlinear optimization, quadrature, and surrogate (meta-) modeling, and indicate Sandia's UQ research directions.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hlthj06utq2k19prpafudohbfg","2009-08-15 10:42:41","2009-10-16 17:04:21"
"515","6","On maximum value principles for finite element approximations","2009-10-06 15:00:00",NULL,"SAS 4201","Junping Wang",,"National Science Foundation","Zhilin LI",,"The purpose of this talk is to discuss how the classical
maximum value principles in PDEs be extended to their numerical
approximations arising from finite element methods. In particular, the
discussion will be primarily focused on the second order elliptic
problem, and the finite element methods shall include standard Galerkin,
P1 non-conforming, and mixed finite elements methods. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rig4i280ssi63p90o8og60l7ps","2009-08-18 12:40:26","2009-09-24 14:41:54"
"517","8","A numerical shortcut for symbolic computation in algebraic geometry","2009-09-23 16:30:00",NULL,"SAS 4201","Dan Bates",,"Colorado State University","Seth Sullivan",,"Many problems in algebraic geometry can be studied via symbolic computation, typically based on some sort of Groebner basis computation.  Another option in many cases is numerical computation, typically rooted in homotopy continuation.  Symbolic methods provide exact results but suffer from some complexity issues.  Numerical methods are often more efficient but provide inexact output.

The focus of this talk is a new technique (joint with J. Hauenstein, T. McCoy, C. Peterson, and A. Sommese) to move from exact input through inexact computations to exact output.  In particular, given an ideal of polynomials with rational coefficients, standard numerical methods will produce witness points (approximations of generic points) on each irreducible component of the algebraic set associated to the ideal.  Given that information, lattice basis reduction algorithms such as LLL can be used to find generators of the ideals corresponding to each irreducible component.  These results can then be verified by (less expensive) symbolic methods.  It appears that this new method will be handy in a number of situations, at least a few of which will be discussed.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/psf5tefpv8eeodsdufagglliko","2009-08-20 09:46:06","2009-09-21 11:30:08"
"518","3","RNA Configurations and Noncrossing Partitions","2009-09-04 16:00:00",NULL,"SAS 4201","Christine Heitsch",,"Georgia Tech",,,"Under a suitable abstraction, complex biological problems can reveal surprising mathematical structure.  We illustrate this phenomena with results motivated by the folding of RNA sequences. Transitioning between RNA configurations by an appropriate local move, we obtain an isomorphism with the lattice of noncrossing partitions.  This leads to results counting orbits under the  Kreweras complementation map and a new graphical approach to meander enumeration.

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tg4tvr4l1bl1nhr97qmln0amdg","2009-08-21 08:51:25","2009-08-27 17:06:10"
"519","24","Annual Fall Social","2009-08-26 16:00:00",NULL,"SAS 4104",,,,,,"We will be having light refreshments from 4-5:15 followed by our pizza and sandwich dinner from 5:15- 7.  This event will be in the Math Commons, SAS 4104.  Maybe there will even be a prize or two to give away! Hope to see you there!",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/uqb533n2nbdpq67njnmsufmth8","2009-08-21 10:45:44",NULL
"520","6","A Velocity Decomposition Approach for Moving Interfaces in Viscous Fluids","2009-09-22 15:00:00",NULL,"SAS 4201","Anita Layton",,"Duke","Zhilin Li",,"We present a second-order accurate method for computing the
coupled motion of a viscous fluid and an elastic material interface with
zero thickness.  The fluid flow is described by the Navier-Stokes
equations, with a singular force due to the stretching of the moving
interface. We decompose the velocity into a ""Stokes"" part and a ""regular""
part. The first part is determined by the Stokes equations and the
singular interfacial force.  The Stokes solution is obtained using the
immersed interface method, which gives second-order accurate values by
incorporating known jumps for the solution and its derivatives into a
finite difference method. The regular part of the velocity is given by the
Navier-Stokes equations with a body force resulting from the Stokes part.
The regular velocity is obtained using a time-stepping method that
combines the semi-Lagrangian method with the backward difference formula.
Because the body force is continuous, jump conditions are not necessary.
We will also briefly discuss an on-going project, where the velocity
decomposition approach is applied to problems with coupled fluid and
solid.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oc7gtmvlpasnq0gp5mqsd53vog","2009-08-21 16:45:16","2009-09-08 10:51:06"
"521","8","Algebraic Relations Among Solutions of Linear Difference Equations","2009-09-09 16:30:00",NULL,"SAS 4201","Michael Singer","http://www4.ncsu.edu/~singer/","NCSU",,,"The Fibonacci $\{F_n\}$ numbers are defined by a simple difference equation
\[F_{n+2} - F_{n+1} - F_n = 0,  F_0 = F_1 = 1.\]
How does one discover that the Fibonacci numbers satisfy Cassini's Identity 
\[ F_{n+2} F_n - F_{n+1}^2 = (-1)^n?\]

In 2008, Kauers and Zimmermann published an algorithm  that allows one to find the ideal of polynomial relations among sequences defined by linear difference equations with constant coefficients.  We will present an alternate algorithm that generalizes to deal with sequences defined by linear difference equations with polynomial coefficients.  ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9pjfa57tra6kjq87he55g346eg","2009-08-25 14:26:18","2009-08-30 17:55:53"
"522","4","Spike-Time Reliability of Layered Neural Oscillator Networks","2009-09-30 15:00:00",NULL,"SAS 4201","Kevin Lin","http://math.arizona.edu/~klin/index.php","University of Arizona Mathematics Department","Mark Hoefer",,"This talk concerns the reliability of large networks of coupled neural
oscillators driven by fluctuating stimuli.  Reliability means that
upon repeated presentations of a given stimulus, the network gives
essentially the same response each time; whether a network is reliable
can impact its ability to encode information via the precise timing of
spikes.  Focusing on certain layered network architectures commonly
used in neuroscience, I will explain -- via a combination of
qualitative theory and numerical simulations -- how factors like
network architecture affect reliability.   I will also discuss the
effects of noise, and show that some types of noise affect reliability
more seriously than others.

This is joint work with Eric Shea-Brown and Lai-Sang Young.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uclsi62aep4knur3eoqocov5bo","2009-08-26 11:00:25","2009-09-22 09:07:55"
"523","4","Two-Dimensional Supersonic, Superfluidic Flows","2009-09-23 15:00:00",NULL,"SAS 4201","Mark Hoefer","http://www4.ncsu.edu/~mahoefer","NC State Mathematics",,,"Dispersive shock waves (DSWs) are studied theoretically in the context
of two-dimensional (2D) supersonic flow of a superfluid.  Employing
Whitham averaging theory for the repulsive Gross-Pitaevskii (GP)
equation, modeling the superfluidic Bose-Einstein condensate, suitable
jump and entropy conditions are obtained for an oblique DSW, a
fundamental building block for 2D flows with boundaries.  In analogy
to oblique viscous shock waves (VSWs), these conditions yield analytic
relations between Mach number ($M$), velocity deflection angle
($\theta$) and wave angle ($\beta$).  Unlike VSWs, the
$M$-$\theta$-$\beta$ phase diagram for DSWs displays four distinct
regions associated with phase transitions in supersonic flow over a
corner which are predicted and verified by numerical computations of
the GP equation.  Quasi-stationary DSWs, shock detachment due to
transonic flow, spontaneous excitation of vortices and the onset of
turbulent dynamics associated with cavitation of the superfluid are
observed.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lp22guti5euvdtpuge6o3m1h4o","2009-08-26 11:01:56","2009-08-31 15:04:37"
"524","4","Shock waves in particle size segregation","2009-10-21 15:00:00",NULL,"SAS 4201","Michael Shearer","http://www4.ncsu.edu/~shearer/home0.html","NC State Mathematics",,,"Shock waves in continuum models of particle size segregation in avalanches are sharp interfaces separating 
regions of di&#64256;erent concentrations of large and small particles. Under the typical shearing present in avalanche 
&#64258;ow, shocks form from initially smooth conditions, and then break to form mixing zones that evolve and 
propagate with the &#64258;ow. The analysis and simulation of these unexpected patterns are based on the recent 
model of Gray and Thornton, which combines a linear bulk shearing motion in the direction of the avalanche, 
with a nonlinear segregation motion normal to the &#64258;ow. Using techniques from the theory of hyperbolic 
conservation laws, we are able to describe shock formation completely, and to characterize most of what 
happens after a shock breaks. 
In related work, we describe experiments and simulations designed to test the Gray-Thornton model in 
a Couette cell. Here, a layer of small glass spheres lies initially over a layer of larger spheres of the same 
density. Upon rotating the lower con&#64257;ning circular plate, the spheres mix and then resegregate. The Gray 
Thornton model is modi&#64257;ed to account for the non-uniform shear present in this con&#64257;guration. The modi&#64257;ed 
model captures the main features of the evolution, but there are interesting additional e&#64256;ects that are not 
well described by the model. 
This is joint work with graduate students Lindsay May, Nick Gi&#64256;en, and physicist Karen Daniels.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6hb5ijrvqi5ktdip61tu47dgbg","2009-08-26 13:59:31","2009-10-08 15:51:08"
"525","4","Spherically Symmetric Waves for a Liquid/vapor Phase Transition Model","2009-10-14 15:00:00",NULL,"SAS 4201","Xiao-Biao Lin","http://www4.ncsu.edu/~xblin/","NC State Mathematics",,,"Dynamic flow involving liquid/vapor phase transition is an important phenomenon
in many engineering processes. For example,  gasoline in internal combustion engine must be injected into the cylinder, vaporized and well mixed with oxygen before ignited by sparks. Understanding the evaporation process and the relation  among the parameters of the system may help improve the fuel efficiency of the engine. In this talk, we discuss fluid flow involving liquid/vapor phase transition  in a cone shaped section, simulating the flow in fuel injection nozzles. Assuming that the flow is spherically symmetric, and the fluid has high specific heat, we look for standing wave solutions inside the nozzle.

The model consists of a system of viscous conservation laws coupled with a reaction-diffusion equation.
We look for two types of standing waves:
(1) Explosion
(2) Evaporation

If the diffusion coefficient, viscosity and  typical reaction time are small, the system is  singularly perturbed.
Transition from liquid mixture to vapor occurs in an  internal layer inside the nozzle.
First,  a matched formal asymptotic solution is constructed.  Then we look for a real solution near the approximation.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lg45kfa9g98ef598sjpseco9ik","2009-08-26 14:00:15","2009-10-08 15:49:39"
"526","6","Plane Wave Expansions, Optimal Local Radiation Boundary Conditions, and Propagation Algorithms","2009-09-15 15:00:00",NULL,"SAS 4201","Tom Hagstrom","http://faculty.smu.edu/thagstrom/","Southern Methodist University","NA Seminar",,"The fundamental feature of waves is their ability to propagate
long distances relative to their wavelength. Efficient algorithms
for simulating waves deal with this fact by:

   i. Employing high-resolution discretizations;

   ii. Avoiding the sampling of wave fields where possible via the
       use of accurate radiation boundary conditions and fast
       far-field propagation algorithms.

    In this talk we will focus on the second issue, reviewing the disparate
representations which have been proposed and developing a new technique,
the complete plane wave representation, which we prove leads to local 
radiation boundary conditions of optimal complexity for isotropic systems. 
We will also discuss the prospects for the development of fast propagation 
algorithms using the complete plane wave representation as well as other
solution forms. Finally we will list some of the difficult issues which arise when 
considering more complex models. 

 ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dqpn01v342gju29bvpmcfr1lvg","2009-08-27 05:29:09","2009-09-03 07:04:06"
"527","6","Controlling numerical dissipation and time stepping in some multi-scale fluid simulations","2009-11-17 15:00:00",NULL,"SAS 4201","Jian-Guo Liu","http://fds.duke.edu/db/aas/Physics/faculty/jliu","Duke","Alina Chertok",,"In the Eulerian description of fluid dynamics such as compressible gas dynamics and kinetic equation,  numerical dissipations are necessarily introduced to have a stable discretization. One severe difficulty  in multi-scale fluid simulations is the amplification  and accumulation
of  these numerical dissipations due to the dynamics in small scale motions such as fast waves and small  mean free path.

Another known difficulty in multi-scale fluid simulations is the inhibitively small time stepping.
In this talk, we will show that with some proper decompositions of  the underlying, governing equations, these two difficulties can be  removed in the gas dynamics uniformly
with respect to the Mach number, and in the neutron transport equation uniformly with respect to the mean free path.  I will also discuss an effective way to carry out localized kinetic  upscaling in a global fluid model . ","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1c988oqa6uhn9qa2ur0te0a01c","2009-08-28 10:55:13","2009-11-02 11:21:39"
"528","3","The topology of the poset of bipartitions","2009-10-16 16:00:00",NULL,"SAS 4201","Gabor Hetyei",,"UNC-Charlotte",,,"Bipartitional relations were introduced by Foata and Zeilberger, who showed these are precisely the relations which give rise to equidistribution of the associated inversion statistic and major index.  In this talk we consider the natural partial order on bipartitional relations given by inclusion, and explore the topology of its order complex. We will see that bipartitional relations on a set of size $n$ form a graded lattice of rank $3n-2$. The order complex of this lattice is homotopy equivalent to a sphere of dimension $n-2$. Each proper interval in this lattice has either a contractible order complex, or it is isomorphic to the direct product of Boolean lattices and smaller lattices of bipartitional relations. The main tool in the proofs of these results is discrete Morse theory as developed by Forman, and an application of this theory to order complexes of graded posets, designed by Babson and Hersh.  

This is joint work with Christian Krattenthaler. ",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dbgue2f6lvbsuj6bdfprjsrcc0","2009-08-28 21:14:26","2009-09-15 08:37:31"
"529","8","Identifiability of phylogenetic mixture models","2009-11-04 16:30:00",NULL,"SAS 4201","Seth Sullivant",,"NCSU",,,"A statistical model is generically identifiable if the map
from parameters to probability distributions is generically one-to-one. We
show that tree parameters of two-tree phylogenetic mixture models are
generically identifiable for the Jukes-Cantor and Kimura 2 parameter
models and verify computationally that the stochastic parameters are
identifiable.
These provide the  first positive results on identifiability of
phylogenetic mixture models with different trees. Proofs rely on a
combination of algebraic geometry, combinatorics, and symbolic
computation.

I will spend most of the talk explaining the background of phylogenetic
models, mixture models, and the identifiability problem.  Then I will try
to highlight some algebraic surprises that arise in the proofs.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qn1clk6ns9a0l701fmuia0coqg","2009-08-30 09:39:04","2009-10-28 20:57:50"
"530","8","The Distribution of the Zeros of the Derivatives of the Riemann Zeta Function","2009-10-21 16:30:00",NULL,"SAS 4201","Sebastian Pauli",,"UNC Greensboro","Seth Sullivan",,"We investigate the distribution of the zeros of the derivatives of the Riemann Zeta function and find unexpected regularity in their distribution.  For higher derivatives we give rectangular regions, which contain exactly one zero.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2ufnuvf1uliorm9doe4ecnr0i8","2009-08-31 10:49:25","2009-10-13 21:09:35"
"531","14","Departmental Tea and Cookies","2009-09-02 15:00:00",NULL,"Math Commons SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gvdd2q5ed0uq7m7svcjl50vcuo","2009-09-01 09:12:36",NULL
"532","22","Hey! That's not my hat!  Derangements and the number e","2009-09-02 16:00:00",NULL,"SAS 2202","Nathan Reading","http://www4.ncsu.edu/~nreadin","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/090209.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fd2g9j2ljr0jo51m4iifhfa6m4","2009-09-02 08:19:30",NULL
"534","22","Derivatives and Vibrating Structures","2009-09-16 16:00:00",NULL,"SAS 2229","Ralph Smith","http://www4.ncsu.edu/~rsmith","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/091609.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8dglo0c1qln070a9p7iqtvctf0","2009-09-02 08:23:50","2009-09-08 14:22:03"
"535","22","The Platonic Solids and the Four Color Theorem: An Introduction to Planar Graphs","2009-09-09 16:00:00",NULL,"SAS 2229","Molly Fenn","http://www4.ncsu.edu/~mafenn2","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/090909.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ptm1sv2sk3bdcik5646oq37tfk","2009-09-02 08:24:56","2009-09-08 13:41:58"
"536","22","Cayley's Formula","2009-09-23 16:00:00",NULL,"SAS 2229","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/%7Enreadin/sum/fall2009/092309.pdf","Say you have n computers (labeled 1, 2, . . . , n), and you start connecting pairs of computers with wires. The computers can relay messages, so, for example, if 1 is connected to 4 and 4 is connected to 7, then 1 and 7 can communicate.
This network of computers is an example of a graph: the computers are vertices and the wires are edges. If we connect all computers together with the smallest possible number of wires (n &#8722; 1), the graph is called a tree. Cayley’s formula tells us that there are n<sup>n&#8722;2</sup> ways are there to connect the n computers with only n&#8722;1 wires. I’ll explain this surprisingly simply formula, and discuss the connection to the symmetric group of permutations. No prior knowledge of graphs, trees, the symmetric group, or permutations will be assumed. The talk will be accessible to all undergraduates.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jimjclsotnfaomfptedvdshsbk","2009-09-02 08:25:51","2009-09-20 21:24:46"
"537","22","Unfolding polyhedra","2009-09-30 16:00:00",NULL,"SAS 2229","Ezra Miller","http://www.math.duke.edu/~ezra","Duke University",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/093009.pdf","Most of us, as children, saw those paper or cardboard cutouts, which we could call “foldouts,” whose edges glue to form (boundaries of) 3-dimensional convex polyhedra.  Just how did anyone figure out how to make them? Given a 3-dimensional convex polyhedron, does there always exist a foldout in the plane? What about higher dimensions? These questions have surprising answers, depending on the precise meaning of “foldout.” This talk will be accessible to all undergraduates, with tons of pictures to help us foray into four dimensions (though most of the talk will be in three or fewer), and absolutely no formulas.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qntthmvj9lq0tdjvp5op9873es","2009-09-02 08:26:53","2009-09-21 09:01:04"
"539","22","Where is the best seat in a movie theatre?","2009-10-21 16:00:00",NULL,"SAS 2229","Alina Duca",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/102109.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gn9q5uktgqt5u800s3onjk5e1s","2009-09-02 08:31:00","2009-10-19 12:26:20"
"540","22","Modeling Dynamics of Social Interactions","2009-10-28 16:00:00",NULL,"SAS 2229","Negash Medhin","http://www4.ncsu.edu/~ngmedhin","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/102809.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9sm0h7oq16f741192k404nv2ro","2009-09-02 08:32:08","2009-10-19 12:27:06"
"541","22","Finding Message in the Noise: Mathematics of Direct-Sequence Spread Spectrum","2009-11-04 16:00:00",NULL,"SAS 2229","Anjela Govan",,"Northrop Grumman",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/110409.pdf",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ckhcgmjhv50dr8nngqgqja4h8g","2009-09-02 08:33:47","2009-10-19 12:27:56"
"542","22","Getting in Control","2009-11-11 16:00:00",NULL,"SAS 2229","Stephen Campbell","http://www4.ncsu.edu/~slc","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/111109.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i37li8ap4akealimb04qkmsit4","2009-09-02 08:34:50","2009-11-09 10:15:31"
"543","22","Ramanujan: The man who knew numbers","2009-11-18 16:00:00",NULL,"SAS 2229","Kailash Misra","http://www4.ncsu.edu/~misra","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2009/111809.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2espafogj3hhc4ftfnt89i57h0","2009-09-02 08:36:22","2009-11-11 14:42:23"
"544","4","Filtering Turbulent Sparsely Observed Geophysical Flows","2009-10-28 15:00:00",NULL,"SAS 4201","John Harlim","www4.ncsu.edu/~jharlim","NC State Mathematics","Mark Hoefer",,"Filtering sparsely turbulent signals from nature is a central problem of contemporary data assimilation. In this talk, I will discuss filtering sparsely observed turbulent signals in which we simulate observations by adding white noise to solutions of the quasi-geostrophic (QG) model with turbulent cascades from baroclinic instability. In particular, we consider two separate regimes with varying Rossby radius mimicking the ``atmosphere'' and the ``ocean''. In the ``atmospheric'' case, large scale turbulent fluctuations are dominated by barotropic zonal jets with non-Gaussian statistics while the ``oceanic'' case has large scale blocking regime transitions with barotropic zonal jets and large scale Rossby waves.
I will discuss how to use tools from applied mathematics to develop cheap reduced stochastic filters, including the radical linear stochastic filters with model errors and the very recently developed exactly solvable Stochastic Parameterization Extended Kalman Filter (SPEKF) with additive and multiplicative bias corrections ``on the fly''. We will compare these cheap reduced filtering strategies with the state-of-the-art Local-Least-Squares Ensemble Adjustment Kalman Filter (LLS-EAKF) and we shall see that the cheap filters supersede the sophisticated LLS-EAKF in the numerically stiff ``oceanic"" regime.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6om8sl274oe78kp9pni6vvqe04","2009-09-04 09:12:52","2009-10-21 09:20:42"
"545","4","Conservation Laws with Prescribed Eigencurves","2009-09-16 15:00:00",NULL,"SAS 4201","Irina Kogan","http://www4.ncsu.edu/~iakogan/","NC State Mathematics","Mark Hoefer",,"We study the problem of constructing systems of hyperbolic conservation laws in one space dimension with prescribed eigencurves, i.e. the eigenvector fields of the Jacobian of the flux are given. We formulate this as a typically overdetermined  system of equations for the eigenvalues-to-be. Equivalent formulations in terms of differential and algebraic-differential equations are considered. The resulting equations are then  analyzed using appropriate integrability theorems (Frobenius, Darboux and Cartan-Kähler). We give a complete analysis of the possible scenarios, including examples, for systems of three equations. As an application we characterize conservative systems with the same eigencurves  as the Euler system for 1-dimensional compressible gas dynamics. The case of general rich systems of any size (i.e. when the given eigenvector fields are pairwise in involution; this includes all systems of two equations) is completely resolved and we consider various examples in this class.  This is a joint work with Kris Jenssen from Penn State University.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5t7sr8ue5oge100bugtg1s120k","2009-09-05 17:47:56","2009-09-06 12:07:38"
"546","4","Statistical properties of dynamical systems","2009-11-19 14:30:00",NULL,"SAS 4201","Matthew Nicol","http://www.math.uh.edu/~nicol/","University of Houston Mathematics Department","Dmitry Zenkov",,"We discuss recent progress in understanding certain key statistical properties of nonuniformly hyperbolic dynamical systems, in particular large deviations, extreme value theory and approximation by Brownian motion.

(This Differential Equations seminar is joint with the Probability and Random Systems seminar) ","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t166ko0il3ddhs9ofg6d62034s","2009-09-06 11:59:36","2009-11-02 09:05:46"
"547","23","Fundamentals of Webdesign Using Dreamweaver","2009-09-11 15:00:00",NULL,"SAS 4201","Seyma Bennett-Shabbir",,"NC State",,,"Effective webpages are an increasingly important medium for disseminating information related to classes and research.  For TA's, they provide a critical way to share material with your class whereas for those entering the job market, they are often checked by potential employers interested in obtaining more information about candidates.  Hence it is important to construct and maintain your webpage in a manner that is both easy and professional.

In this session, Seyma will discuss the use of Dreamweaver, which is one of the most widely used software packages for webpage design.  Dreamweaver is available on machines in the Multimedia Center and across campus.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ib7ckn47e4jknrtdc91ara3vus","2009-09-08 13:24:19",NULL
"548","14","Departmental Tea and Cookies","2009-09-09 15:00:00",NULL,"Math Commons",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i26mmc4bvturlsh311uuqdc2v8","2009-09-08 13:41:23",NULL
"549","8"," Extracting Numerical Factors of Multivariate Polynomials from Taylor Expansions and Beyond","2009-09-16 16:30:00",NULL,"SAS 4201","Wen-shin Lee",,"University of Antwerp","Erich Kaltofen",,"We present a method to extract factors of multivariate polynomials
with complex coefficients in floating point arithmetic. We establish
the connection between the reciprocal of a multivariate polynomial and
its Taylor expansion. Since the multivariate Taylor coefficients are
determined by the irreducible factors of the given polynomial, we
reconstruct the factors from the Taylor expansion. As each irreducible
factor, regardless of its multiplicity, can be separately extracted,
our method can lead toward the complete numerical factorization of
multivariate polynomials.

Besides the numerical factorization, we plan to further comment on a
recently revealed link between Pade approximation theory and
polynomial algebra, which may provide us with an additional tool to
extract algebraic structure from numerical partial data.

This is joint work with Annie Cuyt at University of Antwerp in Belgium.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qgacqmfqgnoudfau5l0sc83hjc","2009-09-08 14:52:45","2009-09-09 16:16:46"
"550","8","Variant Quantifier Elimination: Algorithm and Application","2009-10-07 16:30:00",NULL,"SAS 4201","Mohab Safey El Din",,"Pierre et Marie Curie University & LIP6 INRIA Paris-Rocquencourt","Hoon Hong",,"Joint work with Hoon Hong, NCSU, USA

We study a variant of the real quantifier elimination problem (QE). The variant problem requires the input to satisfy a certain extra condition, and allows the ouput to be almost equivalent to the input. In a sense, we are strengthening the pre-condition and weakening the post-condition of the standard QE problem. The motivation/rationale for studying such a variant QE problem is that many quantified formulas arising in applications do satisfy the extra conditions. Furthermore, in most applications, it is sufficient that the ouput formula is almost equivalent to the input formula. Thus, we propose to solve a variant of the initial quantifier elimination problem. We present an algorithm (VQE), that exploits the strengthened pre-condition and the weakened post-condition. The main idea underlying the algorithm is to substitute the repeated projection step of CAD by a single projection without carrying out a parametric existential decision over the reals. We find that the algorithm VQE can tackle important and challenging problems, such as numerical stability analysis of the widely-used MacCormack's scheme. The problem has been practically out of reach for standard QE algorithms in spite of many attempts to tackle it. However the current implementation of VQE can solve it in about 1 day.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/humhle3ien22j5ufof83hoialc","2009-09-08 15:22:21","2009-09-30 19:57:14"
"551","8","A baby steps/giant steps probabilistic algorithm for computing roadmaps in   smooth bounded real hypersurface","2009-10-14 16:30:00",NULL,"SAS 4201","Mohab Safey El Din",,"ierre et Marie Curie University & LIP6 INRIA Paris-Rocquencourt","Hoon Hong",,"Joint work with Eric Schost, Univeristy of Western Ontario, Canada

We consider the problem of constructing roadmaps of real algebraic
sets. This problem was introduced by Canny to answer connectivity
questions and solve motion planning problems. Given $s$ polynomial
equations with rational coefficients, of degree $D$ in $n$ variables,
Canny's algorithm has a Monte Carlo cost of $s^n\log(s) D^{O(n^2)}$
operations in $\mathbb{Q}$; a deterministic version runs in time $s^n
\log(s) D^{O(n^4)}$.  A subsequent improvement was due to Basu,
Pollack and Roy, with an algorithm of deterministic cost $s^{d+1}
D^{O(n^2)}$ for the more general problem of computing roadmaps of a
semi-algebraic set ($d \le n$ is the dimension of an associated
object).

We give a probabilistic algorithm of complexity $(nD)^{O(n^{1.5})}$
for the problem of computing a roadmap of a closed and bounded
hypersurface $V$ of degree $D$ in $n$ variables, with a finite number
of singular points. Even under these extra assumptions, no previous
algorithm featured a cost better than $D^{O(n^2)}$.


",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k7rl9tc7vqcq51mro8t7qft6n8","2009-09-08 15:23:44","2009-10-06 21:43:48"
"552","4","Stability and fluctuations for traveling waves in an inhomogeneous medium","2009-12-02 15:00:00",NULL,"SAS 4201","James Nolen","http://math.duke.edu/~nolen/","Duke Mathematics","Mark Hoefer",,"I will talk about generalized traveling waves for scalar reaction diffusion equations in an inhomogeneous environment. As the name suggests, these solutions generalize the traditional notion of a traveling wave, although the wave profile is not fixed and the wave speed may not be well-defined.  These solutions are stable attractors.  If the environment has a certain statistical structure, then the asymptotic wave speed is well-defined, and the wave-front moves like a Brownian motion with positive drift.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7cjcbv9laeq7gkskcropn1npt8","2009-09-09 17:19:28","2009-11-30 10:05:12"
"553","8","Equivalence of Curves Under Generalized Weak Perspective Projection","2009-12-02 16:30:00",NULL,"SAS 4201","Joseph Burdis",,"NCSU","Irina Kogan",,"We consider a correspondence problem for curves under central and parallel
projections from R^3 to R^2.  The problem is motivated by applications in
computer image recognition. We show how to reduce the projection problem
to the problem of equivalence of planar curves under affine and projective
groups of transformation.  The latter problem can be solved using Cartan's
moving frame method. This leads to an algorithms for deciding whether a
given spatial curve and a given planar curve are related by a projection
from given class.  This is a joint work with Irina A. Kogan.
","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vq26tbfu1ug6ic0i6tssr17je8","2009-09-10 13:14:14","2009-12-01 10:21:19"
"554","8"," Pairing computation for cryptography (Overview and Recent Progress)","2009-09-30 16:30:00",NULL,"SAS 4201","Eunjeong Lee",,"NCSU","Hoon Hong",,"A pairing is a bilinear map among groups, whose theory was developed
by Weil and Tate in the context of algebraic geometry.
Later it was discovered that the pairing could be used for cryptography.
Since then, intensive research has been carried out on the topic.
By now the pairing is considered to be one of the most important
tools in cryptography.

In this talk, we provide an introductory overview on

* what pairings are,
* how they can be used for cryptography,
* two celebrated pairings (""Tate"" and ""Ate"")

We will also present an improved pairing (which we call ""R-Ate""),
which turns to be optimal on certain elliptic curves.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ugejbn7omesq9hr3odkvvbpap8","2009-09-10 15:38:38","2009-09-17 10:18:15"
"555","6","Some graph optimization problems in data mining","2009-12-03 14:00:00",NULL,"SAS 4201","Paul Van Dooren","http://www.inma.ucl.ac.be/~vdooren/","Catholic University of Louvain, Belgium","Ilse Ipsen",,"Graph-theoretic ideas have become very useful in understanding modern large-scale datamining techniques. We show in this talk that ideas from optimization are also quite useful to better understand the numerical behaviour of the corresponding algorithms. We illustrate this claim by looking at two specific graph theoretic problems and their application in datamining.
The first problem is that of reputation systems where the reputation of objects and voters on the web are estimated; the second problem is that of estimating the similarity of nodes of large graphs. These two problems are also illustrated using concrete applications in datamining.
","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1ea3q9khrnmvnavmqofqboo0js","2009-09-11 15:26:18","2009-11-23 08:18:58"
"556","19","From Amoebas to Tropical Varieties","2009-09-14 15:00:00",NULL,"SAS 2106","Chirag Lakhani","http://www4.ncsu.edu/~cmlakhan/","NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6ksi9s87t18omdcfd9uhmrrg9s","2009-09-12 20:50:52","2009-09-12 20:51:26"
"557","23","Poster Design","2009-09-18 15:00:00",NULL,"SAS 4201","Adam Attarian",,"NC State Mathematics Graduate Student",,,"Posters comprise an increasingly popular medium to disseminate research at conferences and workshops and are becoming required at certain meetings.  However, the design of effective posters differs significantly from that of research talks.

The speaker will discuss techniques pertaining to highly effective poster design and construction using pages, PowerPoint and LaTeX.  In addition, there will be general discussion regarding the layout of effective posters.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pm67cpl094ss7evljius1iio0g","2009-09-14 15:45:44",NULL
"558","6","Adjoint-based error estimates for a Cartesian grid finite volume method for diffusion problems with discontinuous coefficients","2009-11-10 15:00:00",NULL,"SAS 4201","Michael Pernice",,"Idaho National Laboratory","NA Seminar; NE Department",,"Finite volume methods on Cartesian grids are widely used in scientific
and engineering applications due to their simplicity and local
conservation properties.  Diffusion operators with discontinuous
coefficients are encountered in many application areas such as heat
conduction, diffusion approximations to radiation transport, and
subsurface flow.  Convergence analysis and error estimation for such
operators is difficult due to lack of smoothness in the solution.
However, adjoint-based techniques are well suited for developing sharp
error estimates.

Our approach is based on replacing the original problem by a surrogate
problem in which the discontinuous coefficient is replaced by a smooth
one.  We then combine an adjoint-based estimate of the error in the
surrogate problem with an estimate of the difference between the
solutions of the original and surrogate problems.  The adjoint-based
estimate exploits a well-known equivalence between the finite volume
discretization and a mixed finite element discretization with
appropriate quadrature rules.  Numerical results demonstrate the
effectiveness of our approach.

This is joint work with H. Wang (Michigan Technological University)
and D. Estep (Colorado State University). ","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vv1krlathsb60sm2pl6vhp0rak","2009-09-15 09:28:17","2009-11-02 11:21:17"
"559","3","Combinatorial ""Sum Equals Product"" Identities from Lie Theory","2010-02-26 16:00:00",NULL,"SAS 2102","Robert Proctor",,"UNC Chapel Hill",,,"We are concerned with producing generating function identities for partitions and plane partitions, such as those studied by Euler, MacMahon, and Stanley.  Some precursor formulas are first obtained by forming limits of Weyl and Demazure characters of simple and of Kac-Moody algebras.  (Nonetheless, most of this talk should be accessible to combinatorialists,  especially those who are familiar with Schur functions.)  These formulas are due to Shrawan Kumar and Dale Peterson.  In the past we have indicated how to apply the precursor formulas to obtain a generalization of the hook length formula for standard Young tableaux to all  d-complete posets.  In this talk the precursor identities will be emphasized, including a brief mention of their algebraic geometric origin from Kac-Moody Schubert varieties.

","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ql9d1p3c7vf0h254qub404hmqs","2009-09-16 19:17:17","2010-02-16 21:23:52"
"560","14","Webassign Issues","2009-09-22 15:00:00",NULL,"SAS 2106","John Risley",,"Webassign",,,"A town hall style meeting on the topic of WebAssign will be
held for the NCSU Math Department.  Both the President and the CEO of WebAssign will be there to give you information and answer your questions about the recent difficulties that we've experienced.

This meeting is open to anyone in the department.

Below is an outline of what you can expect:
1.  Overview of the Capacity Issue
2.  Steps that WebAssign is taking to monitor capacity moving forward
3.  Discussion/ideas for improving WebAssign
4.  Q&A",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/csg6ea32mvgbrdlq8ljjrrhkb8","2009-09-17 09:44:02","2009-09-17 09:44:31"
"561","7","Metastability in a nearly-Hamiltonian system","2009-10-05 15:00:00",NULL,"SAS 4201","Dr. Avanti Athreya",,"SAMSI","Min Kang",,"Metastability can be understood through the theory of large
deviations for dynamical systems subject to random 
perturbations.  In particular, we present some results on 
averaging and metastability in a Hamiltonian system with 
both deterministic and random perturbations.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0btf8lvdq6es0k2aqgi7dgh4rk","2009-09-17 13:41:48","2009-10-01 17:42:14"
"562","7","Adaptation and Sequential Monte Carlo algorithms: new theory and algorithms","2009-10-19 15:00:00",NULL,"SAS 4201","Julien Cornebise","http://fds.duke.edu/db/aas/stat/faculty/jcornebise","Duke university and SAMSI","Min Kang",,"In the last 15 years, Sequential Monte Carlo 
algorithms, also known as particle filters or sequential importance sampling, have reached
widespread use in the most intricate problems, ranging from
non-linear non-gaussian stochastic filtering to Bayesian sequential
estimation, with applications to finance, signal processing,
robotics, and population genetics, to name a few.
They basically in at approximating a sequence of intricate distributions by
updating a weighted sample through Markovian probability kernels, hence sampling
from ""easy"" distributions, and reweighting by adequate Radon-Nikodym derivatives.
In this talk, we will show how state-of-the-art Sequential Monte algorithms,
encompassed in the auxiliary particle filter framework from Pitt and
Shephard (1999, JASA), can be taken to new heights and deal with
models of soaring complexity, including multi-modal or highly
non-linear target kernels and distributions.
We will first present new theoretical results that serve as a basis to our
algorithms -- rather than empirical ad hoc methods, as has been
common practice so far. We link common quality criteria (namely the
coefficient of variation and entropy of the importance weights) to
commonly used divergences between probability measures, such as chi-square and
Kullback-Leibler divergence, both asymptotically and for finite sample size.
We will then show how adaptation of the proposal kernel and of the adjustment
multiplier weights stem from these criteria, sharing common ground with pilot
sampling, mixture of experts, EM algorithm and its SAEM and MCEM
variants.
After simulation examples that allow for both rigorous and intuitive
visual interpretation, we will conclude on the perspective of
extensions to the latest Sequential Monte Carlo methods, such as the
SMC samplers of Del Moral, Doucet and Jasra, (2006, JRSSB).",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8eho9ghv58tc4hpl5429l9dvh0","2009-09-17 14:22:31","2009-10-05 19:10:02"
"563","7","Statistical properties of dynamical systems","2009-11-19 14:30:00",NULL,"SAS 4201","Matthew Nicol","http://www.math.uh.edu/~nicol/","University of Houston Mathematics Department","Dmitry Zenkov",,"We discuss recent progress in understanding certain key statistical properties of nonuniformly hyperbolic dynamical systems, in particular large deviations, extreme value theory and approximation by Brownian motion.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/keg2h209vtpdp8v47b1m833qco","2009-09-17 14:36:13","2009-11-02 11:49:37"
"564","7","On Non-Parametric Wavelet Regression with Long Memory Errors","2009-11-09 15:00:00",NULL,"SAS 4201","Linyuan Li","http://www.math.unh.edu/~linyuan/","University of New Hampshire","Min Kang",,"We consider the wavelet-based estimators of the mean regression functions with long memory errors (e.g., fractional Gaussian processes or infinite moving average processes) and investigate their asymptotic rates of convergence of estimators based on thresholding of empirical wavelet coefficients. We show that these estimators achieve nearly optimal minimax convergence rates with a logarithmic term over a large range of Besov function classes. Therefore, in the presence of long memory correlated errors, our estimators still achieve nearly optimal convergence rates.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eb5r5opb8e6avk9rdeq4n8iue0","2009-09-17 14:38:18","2009-10-06 15:45:35"
"565","7","Nonequilibrium Steady States of Certain Dynamical Transport Models","2009-11-23 15:00:00",NULL,"SAS 4201","Kevin Lin","http://math.arizona.edu/~klin/index.php","University of Arizona","Min Kang",,"In statistical physics, ""nonequilibrium steady states"" refer to the
processes that take place in systems maintained out of thermal
equilibrium, for example heat flow across a rod whose ends are held at
different temperatures.  This talk concerns nonequilibrium steady
states in a class of models introduced by J.-P. Eckmann and L.-S.
Young as paradigms for transport processes.  In these models,
energetic particles are injected and absorbed by heat reservoirs into
the system at the boundary; these particles interact with local
degrees of freedom and carry energy around the system.   I will review
a strategy for predicting macroscopic profiles (e.g., mean energy at
each site) in these models using the assumption of local thermal
equilibrium (LTE).  I will discuss numerical evidence for the
effectiveness of this prediction strategy and the validity of the LTE
assumption, as well as the results of a numerical study of spatial
correlations in these models.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9qtdm9ubf20gf1bv5j77kj7n20","2009-09-17 14:48:40","2009-11-16 17:35:18"
"566","14","Departmental Tea","2009-09-18 14:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/uno23camclftvcv9nfbfef9v7o","2009-09-18 07:33:30","2009-09-18 09:05:11"
"567","3","Basis Reduction, and the Complexity of Branch-and-Bound","2009-10-30 16:00:00",NULL,"SAS 4201","Gabor Pataki",,"UNC Chapel Hill",,,"The classical branch-and-bound algorithm for the integer feasibility problem is considered inefficient: it may take an exponential number of nodes to prove the infeasibility of a simple integer program.  Theoretically efficient algorithms, such as Lenstra's and Kannan's algorithms, and the generalized basis reduction method of Lovasz and Scarf use advanced techniques. The first two of these need to round the polyhedron (i.e. apply a transformation to it to make it look ""more spherical); and the last solves a sequence of linear programs to find a direction in which the polyhedron is ""thin"".

Here we show that branch-and-bound is theoretically efficient, if we apply a unimodular transformation to the constraint matrix to make its columns short, and near orthogonal, i.e. a reduced basis of the generated lattice. The main result is that if the coefficients of the problem are from {1, ..., M} for a large enough M, then for almost all instances the number of subproblems that must be enumerated by branch-and-bound is just {\em one}. Besides giving an analysis of branch-and-bound, the solvability result generalizes work of Furst and Kannan on the solvability of subset sum problems.

Joint work with Mustafa Tural at UNC Chapel Hill (now at Telcordia Laboratories).
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qpepunr2ek5us77nsepgcr2vuk","2009-09-19 12:45:59","2009-09-29 15:51:44"
"568","3","Triangle Lectures in Combinatorics","2010-02-06 10:00:00",NULL,"SAS 1102","Carla Savage, Bernd Sturmfels, Ed Swartz, Laszlo Szekely",,"Various Universities",,,,"plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3uhc0k13o5bonpqtgu8ki5cqfo","2009-09-20 20:19:09","2010-02-01 13:40:47"
"569","9","A Comparison of Standard Error Computations Using Asymptotic Theory   and Bootstrapping","2009-09-23 16:00:00",NULL,"Cox 306","Danielle Robbins",,"NC State Graduate Student",,,"When modeling biological and engineering processes, the inverse problem is very important in the estimation of parameters within the model.   Associated with these parameter estimates is a certain amount of error, which can  be quantified via asymptotic theory or bootstrapping methods. We  investigate
computationally the bootstrapping approach and the asymptotic theory approach to computing parameter standard errors for data with several noise forms and levels. We consider both constant variance absolute  error data and relative error which produces non-constant variance data in our parameter estimation formulations. We compare and contrast parameter
estimates, standard errors, confidence intervals, and computational  times for both bootstrapping and asymptotic theory methods.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p9krmu12ap616p3c9bsmbae08k","2009-09-21 11:10:33",NULL
"570","23","Topic Fundamentals of Latex","2009-09-25 15:00:00",NULL,"SAS 4201","Zhengzheng Hu",,"NC State",,,"This will include discussion regarding the installation of Latex on your own machine as well as various typesetting commands and strategies including the incorporation of figures in documents. The presentation will thus include topics of interest for both beginning Latex folks and those interested in some of the more detailed points.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jsarl7tje3r3vt8md3d58g20vo","2009-09-21 11:27:32","2009-09-21 11:58:20"
"571","4","Darwin's theorem, Taylor Diffusion, and falling spheres in stratified fluids","2009-11-04 15:00:00",NULL,"SAS 4201","Rich McLaughlin","http://www.amath.unc.edu/Faculty/rmm/","UNC Applied Math","Mark Hoefer",,"The motion of bodies falling through stratified fluids arises naturally in the context of carbon (marine snow) settling in the ocean, and the details of the settling rates may play a role in assessing the role of the ocean in the earth's carbon cycle.  In this lecture, we look at phenomena associated with falling spheres in stratified fluids, and in particular focus upon the critical parameters setting when transient sphere levitation is possible.  Some of the mechanisms responsible for this behavior are related to fluid entrainment (Darwin drift), and anomalous mixing of the entrained fluid (Taylor diffusion).  We review the results of Darwin and Taylor, and present new results regarding anomalous short time mixing, and asymptotic corrections to Darwin's drift volume.  New arrestment criteria derived from the energetics of the fluid+body system will be presented and compared to experimental observations.  

this is joint work with Roberto Camassa, Joyce Lin, Zhi Lin, Keith Mertens, Matthew Moore, Ashwin Vaidya, and Claudio Viotti","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tvb6itkqk3bddlrhd4cgqghebo","2009-09-21 15:29:31","2009-10-29 10:15:04"
"572","14","Departmental Tea and Cookies","2009-09-23 14:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p08f6h3fu2ljfhs34b26dgjpsk","2009-09-21 16:47:22","2009-09-21 16:48:08"
"573","3","Combinatorics of Involutions and Twisted Involutions in Coxeter Groups","2009-11-20 16:00:00",NULL,"SAS 4201","Ruth Haas",,"Smith College",,,"The set of involutions of a Coxeter Group can be generated starting from the identity giving a poset. This poset is similar to the weak order poset for the whole  group, whose combinatorics is important in representation theory and has been studied extensively by many mathematicians. The combinatorics of the involution poset is also of fundamental significance in the study of symmetric spaces and their representations. This talk will focus on the combinatorics of this poset.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fhuama8ph1iqnup6ttql65eh00","2009-09-27 15:29:55","2009-11-15 22:16:28"
"574","23","Research and Teaching Statements","2009-10-02 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"For students and postdocs applying for either academic or nonacademic positions, research statements are often required as part of the application package.  Additionally, teaching statements are typically required when applying for academic positions.  In this week's RTM, a faculty panel will discuss strategies for writing effective research and teaching statements.  Examples of both will be provided during the discussion.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8iq3r4v1fab8l57h5d7gujuou8","2009-09-28 09:49:25",NULL
"575","14","Departmental Tea and Cookies","2009-09-30 14:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s5774n8163i6oh5k03hgn6rvd8","2009-09-28 12:13:48",NULL
"577","27","Southeast-Atlantic Section Conference of the Society for the   Industrial and Applied Mathematics (SIAM-SEAS 2010)","2010-03-20 08:00:00","2010-03-21 17:00:00","SAS Hall",,,,"Dr. Jeff Scroggs","http://www4.ncsu.edu/~scroggs/SIAMSEAS/","The thirty-fourth annual meeting Southeast-Atlantic Section of the Society for the Industrial and Applied Mathematics (SIAM-SEAS 2010) will be held at North Carolina State University, Raleigh, NC, March 20-21, 2010.


Visit the website for more details:
<a href=""http://www4.ncsu.edu/~scroggs/SIAMSEAS/"">http://www4.ncsu.edu/~scroggs/SIAMSEAS/</a>

",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t2emc71537d1nbf9qb7nmjn6c4","2009-10-01 09:23:47","2009-10-01 09:30:45"
"578","15","Opportunities in Mathematical Modeling of Radar Systems","2009-10-05 15:00:00",NULL,"SAS 1216","Teresa Selee",,"Georgia Tech Research Institute","SIAM Student Chapter",,"Georgia Tech Research Institute is a highly-regarded applied research and development organization and was recently voted one of the top 10 places to work in Atlanta. The Institute's expertise includes all areas of radar systems, and the focus of this presentation is two areas of possible interest to mathematicians.

Tracking missiles is an important problem for industry contractors trying to build radar systems as well as government agencies tasked with protecting the United States and her allies. This area includes research in linear and non-linear filtering as well as modeling and simulation. Another area of research involves data “cubes” or tensors of information collected from air-based radars. Linear algebra techniques are applied to help reduce noise and increase visibilities of targets.",,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/onmr976eqcu4arrmegjhnjt8n0","2009-10-02 09:21:54","2009-10-04 23:02:55"
"579","1","Spectrahedra","2010-02-05 15:00:00",NULL,"SAS 1102","Bernd Sturmfels",,"University of California, Berkeley",,NULL,"The set of all positive definite $n \times n$-matrices forms a convex cone. A spectrahedron is the intersection of that cone with a linear space. Spectrahedra are the feasible regions in semidefinite programming, an important current topic in optimization and engineering, so they play a role similar to that enjoyed by convex polyhedra in linear programming. Starting with pictures of multifocal ellipses in the plane, this lecture offers a colorful introduction to the beautiful geometry of spectrahedra.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/4vnft6o35l4tcu4t4pmafcisjs","2009-10-05 10:23:56","2010-02-05 08:26:56"
"580","14","Departmental Tea and Cookies","2009-10-05 15:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gv91iued0i0vh3qt6vj1utfv3k","2009-10-05 12:15:08",NULL
"581","14","Funding Opportunities in the DMS","2009-10-05 16:00:00",NULL,"SAS 4201","Junping Wang",,"NSF",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2dupd9se3l5af1mqg4t7ec74t8","2009-10-05 12:18:59","2009-10-05 13:47:58"
"582","8","""Curious"" Graphs arising from Cyclotomic Polynomials","2009-10-28 16:30:00",NULL,"SAS 4201","Eunjeong Lee",,"NCSU","Hoon Hong",,"In this talk, we investigate puzzling graphs
arising from polynomial operations on cyclotomic polynomials.

Specifically, let Phi_n(x) be a cyclotomic polynomial of n-th order.
Let d be the degree of the remainder of x^i when divided by Phi_n(x).
Of course d depends on i and n.
For a fixed n, imagine the graph of d versus i.
The graphs exhibit intriguing patterns.
We will make several observations on the patterns,
make a few conjectures, and prove some of them,
still leaving many as open problems for the curious minds.

The research was initially motivated by complexity analysis
of a state-of-the-art crypto-system,
where the above question naturally arose.

We also feel that the question is interesting on its own,
because it seems to provide a channel through which
one could gain a deeper understanding on the relations
among the notions such as sparsity and remaindering defects
for cyclotomic polynomials.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/re1p0s917cdphtqcjpogvov2jg","2009-10-05 18:22:42","2009-10-25 20:22:39"
"583","19","Building a Lie Module Homomorphism up to Homotopy","2009-10-12 15:00:00",NULL,"SAS 2106","Michael Allocca",,"NC State",,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6ff12592parpmrgivgosgag3b0","2009-10-12 08:38:38",NULL
"584","14","Departmental Tea and Cookies","2009-10-14 14:30:00",NULL,"SAS 4104",,,,,,,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b90bkin9vtrtrp9vjuupur36lk","2009-10-12 14:06:36",NULL
"585","21","Southeastern Lie Theory Workshop on Combinatorial Lie Theory and Applications","2009-10-09 08:00:00","2009-10-11 13:00:00","SAS 4104, SAS 1102",,,,,"http://www4.ncsu.edu/%7Emisra/SELie/index.htm",,,"1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0dlml35d0emerjkd04bglk65rs","2009-10-13 09:55:13",NULL
"586","3","W-algebra extensions of minimal models","2010-03-05 16:00:00",NULL,"SAS 4201","Antun Milas","http://math.albany.edu/~am815139/","University at Albany",,,"Nonsemisimple (or logarithmic) conformal field theories have attracted a lot interest in recent years. From vertex algebra point of view, a LCFT amounts to a finite tensor category coming from a C_2-cofinite vertex algebra.

I will explain structure and representations of a family of W-algebras obtained as extension of the Virasoro vertex algebra of minimal central charge, and in particular the c=0 algebra. These vertex algebras are expected to be in Kazhdan-Lusztig correspondence with certain finite-dimensional quantum groups. Modular invariant partition function, Verlinde formula, and some surprising applications will be also discussed.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a5rrp64cqo9cp002aomk8rdv18","2009-10-13 12:35:12","2010-03-01 14:42:37"
"587","3","Finite-dimensional representations of quantum affine algebras at roots of unity","2010-03-12 16:00:00",NULL,"SAS 4201","Dijana Jakelic","http://people.uncw.edu/jakelicd/","UNC Wilmington",,,"The category of finite-dimensional representations of quantum affine algebras is not a semisimple category, however its simple objects are highest-weight in an appropriate sense. For generic values of the quantization parameter,  results of Chari and Kashiwara provide a useful way of obtaining indecomposable objects by giving sufficient conditions for a tensor product of simple objects to be highest-weight. In particular, a tensor product of fundamental representations can always be reordered in such a way that these conditions are  satisfied. This property turned out to be one of the essential ingredients used to describe the block decomposition of the category. 

In this talk, we will focus on a joint work with A. Moura where we consider the root of unity case. We prove an analogue of Chari's version of the aforementioned result on tensor products of simple modules. However, the result about tensor products of fundamental representations is no longer valid. After reviewing the basics on finite-dimensional representations of quantum affine algebras, we will discuss the techniques we used to overcome this issue for describing the blocks in the root of unity setting.
","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5v7gl60b9vj8knls2eq71mll2c","2009-10-16 15:01:29","2010-03-08 08:25:34"
"591","23","Final Year Timelines and Strategies","2009-10-23 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"NC State","Ralph Smith",,"The final year of a Masters, PhD or Postdoctoral program involves a number of deadlines and requirements that are often bewildering.  For example, when should one set up their committee, schedule their preliminary exam, apply for jobs, and schedule their defense?  Moreover, how should one budget time for job interviews while finishing their research?  In this RTM, we will discuss a number of these issues to help clarify what needs to be completed during the final year of graduate school or a postdoc program.
",,"1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/smjus4esjesqterj96v9mebdbk","2009-10-19 10:33:55","2009-10-19 10:34:29"
"592","14","Departmental Tea and Cookies","2009-10-21 14:30:00",NULL,"SAS 4104",,,,"math",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2mrajs5t08s2nkbs3he4s9ni3o","2009-10-19 11:24:24","2009-10-20 00:17:07"
"597","3","Additive results for the genrealized Drazin inverse and some applications to block matrices","2009-11-06 16:00:00",NULL,"SAS 4201","Nieves Castro-Gonzalez",,"Polytechnic University of Madrid",,,"The generalized Drazin inverse appears in numerous applications that include areas such as linear estimation, differential and difference equations, Markov chains and control theory.  We present in this talk additive properties for the g-Drazin inverse in a complex Banach algebra.  The auxiliary result used in our development involves an expression for the resolvent of a matrix with entries in a Banach algebra.  We will comment on the application of the Drazin inverse of a 2x2 complex block matrix in terms of the individual blocks and the generalized Schur complement.","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bmrcf4br340mugtv5p0tcl061o","2009-10-21 11:27:31","2009-10-22 14:57:13"
"598","14","Departmental Tea","2009-10-28 14:30:00",NULL,"SAS Hall 4104",,,,,,,"annewkir","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1d3p197fandng4k2cga62usceg","2009-10-26 10:59:05",NULL
"599","23","Final Year Timelines and Strategies: Part II","2009-10-30 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"The final year of a Masters, PhD or Postdoctoral program involves a number of deadlines and requirements that are often bewildering.  For example, when should one set up their committee, schedule their preliminary exam, apply for jobs, and schedule their defense?  Moreover, how should one budget time for job interviews while finishing their research?  In this RTM, we will discuss a number of these issues to help clarify what needs to be completed during the final year of graduate school or a postdoc program.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fn6fhqusbf87duk6aicgg42420","2009-10-26 11:16:19",NULL
"600","3","W-constraints for simple singularities","2009-11-13 16:00:00",NULL,"SAS 4201","Bojko Bakalov","http://www4.ncsu.edu/~bnbakalo/","NC State",,,"Simple singularities are classified by Dynkin diagrams of type ADE. Using Picard-Lefschetz periods, we construct a twisted representation of the lattice vertex algebra V associated to the root lattice of the corresponding finite-dimensional Lie algebra g. By the Frenkel-Kac construction, V is isomorphic to the basic representation of the corresponding affine Kac-Moody algebra, and in particular it admits an action of g by derivations. The kernel of this g-action is a subalgebra of V known as a W algebra. Our main result is that the total descendant potential of the singularity, introduced by Givental, is a highest weight vector for the W algebra. This is joint work with T. Milanov.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/edvt5m46c03uh649ndoo5le6f8","2009-10-30 09:56:30",NULL
"601","23","Research Opportunities and Strategies","2009-11-06 03:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University",,,"Research comprises an important component of both your undergraduate and graduate program.  For undergraduates, it provides an opportunity to see how coursework addresses broader questions in mathematics whereas for graduate students, it additionally constitutes one of the important aspects required for your degree.  In this session, we will discuss strategies for getting involved in research during the final years of your undergraduate or first two years of your graduate program.  This will include: how and when to choose an advisor, choice of qualifying exams, finding an exciting summer internship, and balancing research and other requirements.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/151ehgjpjhb2vcvo2m5enmdifo","2009-11-02 09:18:02",NULL
"602","14","Departmental Tea and Cookies","2009-11-04 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n5jqu2aqo6patsqr1rh8oqqir8","2009-11-02 14:28:49",NULL
"603","3","Path model solutions of total positivity and characters of affine algebras","2010-01-29 16:00:00",NULL,"SAS 4201","Rinat Kedem",,,,,"I will describe some recently discovered connections between the functional equations ($Q$-systems or $T$-systems) satisfied by characters of special affine algebra modules and certain combinatorial structures, such as cluster algebras, path models, and the total positivity conjecture of Fomin and Zelevinsky. The functional equations are discrete evolution equations, and they are integrable in the Liouville sense. This makes them amenable to solution using simple statistical models.  [Joint work with Di Francesco].
","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sgs092qgs9b6kbh7qll71qb818","2009-11-02 16:12:52","2010-01-08 05:33:33"
"604","15","Modeling and Simulation at Idaho National Laboratory","2009-11-10 11:00:00",NULL,"SAS 4201","Michael Pernice",,"Idaho National Laboratory","SIAM Student Chapter",,"Idaho National Laboratory is dedicated to supporting DOE's missions in nuclear energy, renewable energy, and national defense.  Currently celebrating its 60th anniversary, INL began as the National Reactor Testing station and played an important role in the first production of electricity by nuclear power in 1951.  Current research efforts at INL include development of advanced nuclear energy systems, hybrid energy systems, and advanced nuclear fuel cycle technologies. Additional efforts in secure national infrastructure and defense research take advantage of unique features of INL's location.  We discuss modeling and simulation activities in support of INL's mission. ","klrehm","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/m4q4ntjnc594q4dbvmtauskbe4","2009-11-05 11:06:28",NULL
"605","3","Finite vertex algebras","2010-01-22 16:00:00",NULL,"SAS 4201","Alessandro D'Andrea",,"University of Rome ""La Sapienza""",,,"Interesting known examples of vertex algebras are quite large objects - usually graded vector spaces of superpolynomial growth. It is well known that in finite dimensional cases, every vertex algebra structure becomes ""trivial"", in that it collapses to a differential commutative algebra structure. In this talk, I will show that this also happens for simple vertex algebras satisfying some natural finiteness requirement (more or less equivalent to linear growth) and give a characterization of non simple instances.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/piu57sq6kfh8igp2h5scfg8kdg","2009-11-06 11:08:07","2010-01-18 12:09:34"
"606","22","Undergraduate Research Presentations","2009-12-02 16:00:00",NULL,"SAS 2229","Shawn King, Chelsey Cooley, Rachael Gordon-Wright",,"NCSU",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8gnu51045fcnftm43psut8brnk","2009-11-09 10:14:39",NULL
"607","14","Departmental Tea and Cookies","2009-11-10 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/82i3lqao1cpafar1qj78ietstg","2009-11-09 13:50:10",NULL
"608","3","Ideals of Graph Homomorphisms","2009-12-04 16:00:00",NULL,"SAS 4201","Alex Engstrom",,"UC Berkeley",,,"Several of the statistical models treated in algebraic statistics are defined using graph theoretic concepts.  Working with graphs, it is sometimes useful to consider them as objects in a category with graph homomorphisms.  For example in algebraic combinatorics this view point has been very successful.

We will define and describe the ideals of graph homomorphisms.  These ideals generalize toric ideals from algebraic statistics and some of their polytopes are common in optimization theory.  This is in part joint work with Patrick Noren.","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i21amg0picc3ge6b4of1rnl828","2009-11-10 08:17:52","2009-11-29 07:46:27"
"609","14","Departmental Tea","2009-11-18 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bkcdoc15be2hhund3dmiaadohk","2009-11-16 13:27:09",NULL
"610","9","Modeling and Assessment of Cerebral Autoregulation in Chronic Ischemic Stroke","2009-11-18 16:00:00",NULL,"Cox Hall, Rm 306","Mikio Aoi",,"NC State Biomathematics Graduate Student",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jbd6cvsksd191os7ip3n76iv9o","2009-11-16 14:22:32",NULL
"611","23","Interview Do's and Don'ts","2009-11-20 15:00:00",NULL,"SAS 4201","Departmental Faculty",,,"Ralph Smith",,"What type of presentation should you give and what do you do if you cannot answer a question?  Should you try to negotiate salary or benefits during the initial interview?  Is it appropriate to have your mother call the search committee for any reason?  What do you do if your cell phone rings during the interview?  What do you do if you are late for the interview and how should you dress?

These questions and others will be discussed during this week's RTM.  This session should be of interest to all students and postdocs presently looking for a job.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j5tnj3j6v9g4erq51nt3d3j59c","2009-11-16 19:28:39",NULL
"612","14","Departmental Tea","2009-12-02 15:30:00",NULL,"Math Commons, 4104",,,,,,,"annewkir","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/a2bu5cleiqdmlk6qmsmddgfvl4","2009-11-17 08:07:26","2009-11-17 08:08:00"
"613","14","Departmental Tea and Cookies","2009-11-24 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jub315o8ga41q2audle57sei0g","2009-11-23 12:38:46",NULL
"614","9","Probabilistic Allele Calling to Improve Population Size Estimates from Non-Invasive Genetic Mark-Recapture Analysis","2009-12-02 16:00:00",NULL,"Cox 306","Megan Supple",,"NC State Biomathematics Graduate Student",,,"Accurate estimates of population sizes are necessary to help researchers understand how wildlife populations are changing over time.  When sampling rare or elusive species, the limits of traditional mark-recapture methods of population size estimation can sometimes be addressed by utilizing non-invasive genetic mark-recapture methods. Using this method, non-invasive genetic samples, such as hair or scat, are collected and genotyped at multiple microsatellite markers.  One major problem introduced by non-invasive genetic methods is the overestimation of population sizes due to genotyping errors.  To achieve better population size estimates, I propose a new probabilistic allele calling method that assigns probabilities to possible allele calls based on electropherogram peak heights. Using computer simulations, I compared the new allele calling method to a traditional allele calling method.  Estimates from the probabilistic method were less biased and more precise than the traditional method in almost all cases.  This new method of analyzing non-invasive genetic mark-recapture data has the potential to allow wildlife population sizes to be accurately estimated using non-invasive methods in less time and at lower cost than current methods.
","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u1kf4o4m0sv28dmc73fbfdo5rg","2009-11-24 15:05:42",NULL
"615","4","On Coarse-Grained Random Walk Models for Brownian Motors","2009-12-03 11:30:00",NULL,"SAS 4201","Peter Kramer","http://www.rpi.edu/~kramep/","Rensselaer Polytechnic Institute","John Harlim",,"We compute the large-scale transport properties of
the basic flashing ratchet mathematical model for (Brownian) molecular motors and consider in this light whether the underlying continuous-space, continuous-time Markovian model can be coarse-grained as a discrete-state, continuous-time Markovian random walk model.  Through careful computation of associated statistical signatures of Markovianity, we find that such a discrete coarse-graining is an excellent approximation over much but not all of the parameter regime.  In particular, for the parameter values associated with the most efficient operation of the flashing ratchet, the discretized model displays non-Markovian features such as waiting times between jumps which are not exponentially distributed.  We provide a theoretical framework for understanding the conditions under which Markovianity is to be expected in the discretized model and two mechanisms by which the flashing ratchet model coarse-grains to a non-Markovian discretized model.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dqrijsdgqkk70jgg9r9s53cg5g","2009-11-30 09:10:30",NULL
"616","6","TBA","2010-04-15 16:00:00",NULL,"Burlington Labs","Mike Eldred",,"Sandia National Laboratories","NE Department",,,"ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qr221mctnst3v501r5d4ptd7u4","2009-12-01 13:48:58",NULL
"617","3","The conjugacy problem for Coxeter groups","2010-02-12 16:00:00",NULL,"SAS 4201","Matthew Macaulay",,"Clemson",,,"A classic result in Coxeter groups, known as Matsumoto's theorem, states that any two reduced expressions of the same word differ by a sequence of braid relations. Cyclically shifting a reduced expression is a conjugation by the initial letter, and we say that an expression is cyclically reduced if every cyclic shift of it is reduced. We can now ask the following question, which is in a sense a cyclic version of Matsumoto's theorem.

Do two cyclically reduced expressions of conjugate elements differ by a sequence of braid relations and cyclic shifts?

While the answer to this question is ""no,'' it seems to ""usually be true.'' It is rich in combinatorics, and resolving it would settle the conjugacy problem for Coxeter groups. Along the way, we introduce the cyclically fully commutative, and logarithmic elements of Coxeter groups.
","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d922e5l6ind8fo8psgii42u9jc","2009-12-03 21:57:21","2010-01-23 15:22:48"
"618","3","A basis exchange property for matroids","2009-12-11 16:00:00",NULL,"SAS 4201","Johnny Humphries",,,,,"Matroids provide an important abstraction of the notions of independence in vector spaces, graphs and algebraic field extensions. A conjecture of Rota's states that the set of elements from n disjoint bases of a rank-n matroid M can be repartitioned into n transversals that are also bases of M. We present a stronger result for the class of paving matroids and outline the inductive proof, explain why the technique used fails when trying to prove the conjecture directly.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ka0gi7u8un6om196mdtarof5mg","2009-12-10 17:56:05",NULL
"619","14","Tentative TEA","2010-02-05 14:20:00",NULL,"SAS 4104",,,,,,,"annewkir","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/aithen7pd5oud66vm4av8isat0","2009-12-11 14:34:52",NULL
"620","3","Enumeration of plane curves and labeled floor diagrams","2010-02-19 16:00:00",NULL,"HA 4201","Sergey Fomin",,"University of Michigan",,,"Floor diagrams are a class of weighted oriented graphs introduced by E. Brugalle and G. Mikhalkin. Tropical geometry arguments yield combinatorial descriptions of (ordinary and relative) Gromov-Witten invariants of projective spaces in terms of floor diagrams and their generalizations. In the case of the projective plane, these descriptions can be used to obtain new formulas for the corresponding enumerative invariants. In particular, we give a proof of Goettsche's polynomiality conjecture for plane curves, and enumerate plane rational curves of given degree passing through given points and having maximal tangency to a given line. On the combinatorial side, we show that labeled floor diagrams of genus 0 are equinumerous to labeled trees, and therefore counted by the celebrated Cayley's formula. The corresponding bijections lead to interpretations of the Kontsevich numbers (the genus-0 Gromov-Witten invariants of the projective plane) in terms of certain statistics on trees. This is joint work with Grisha Mikhalkin.","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n34pgrnic9dd6p9a86nt4159l4","2009-12-15 10:36:37",NULL
"621","4","Dynamics of Nonlinear Bound States in Inhomogeneous Media","2010-03-24 15:00:00",NULL,"SAS 4201","Boaz Ilan","http://faculty.ucmerced.edu/bilan/index.html","University of California, Merced","Mark Hoefer",,"Nonlinear Schrodinger (NLS) equations are used to model physical phenomena such as intense laser beams and ultra-cold matter waves. These waves can be better confined and controlled when using spatially inhomogeneous media. Examples include light propagation in Photonic Crystal Fibers and Bose-Einstein condensate waves inside an external potential. Nonlinear bound state solutions (often called solitary waves or solitons) offer new insight into the salient features of these complex physical systems. This talk will present recent rigorous, asymptotic and computational results on existence and dynamics of such solutions. The bifurcation of bound states from the edge of spectral bands is analyzed in detail. We prove that in the L2-critical case, perturbed bound states with frequency near the band edge do not undergo wave collapse, yet they are nonlinearly unstable. The ensuing dynamics is elucidated using computations of NLS equations.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jd59eltmghoka3gmkjt3iup4q0","2009-12-28 12:25:49","2010-02-08 16:11:25"
"622","4","Stability analysis of persisting periodic solutions to a complex Ginzburg-Landau perturbation of NLS","2010-03-31 15:00:00",NULL,"SAS 4201","Stéphane Lafortune","http://lafortunes.people.cofc.edu/","College of Charleston","Mark Hoefer",,"It was shown in [Cruz-Pacheco, Levermore, and Luce (2004)] that a certain
 class of periodic solutions to the nonlinear Schrodinger equation (NLS)
 persist when the NLS is subject to a perturbation leading to the Complex
 Ginzburg Landau equation (CGL). In this presentation, I will show how one can
 use methods coming from the theory of integrability together with the Evans
 function to study the spectral stability of these persisting solutions. In
 particular we show that the solutions of NLS are spectrally stable with
 respect to periodic perturbations. However, the solutions can become unstable
 when NLS is perturbed to CGL.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2t6vod4o9e5gb9co1fukbv7ra4","2009-12-30 10:46:42","2010-03-12 15:38:37"
"623","8","The Kernel Method","2010-02-10 15:00:00",NULL,"SAS 1218","Manuel Kauers",,"Research Institute for Symbolic Computation (RISC), Austria","Michael Singer",,"The field of enumerative combinatorics is not only a great source of
complicated expressions and functional equations, but also a great
source of tricks, treatments, and transformations for simplifying
complicated expressions or solving complicated functional equations. A
particularly nice ""trick"" due to Knuth applies to a certain kind of
functional equations that tends to arise in lattice path enumeration
problems. The trick has proven so fruitful that it has been extended and
generalized in several respects and is now commonly known as the kernel
method.

Together with Alin Bostan (INRIA), we have recently used the kernel
method in combination with heavy computer algebra calculations for
proving that a power series describing a certain lattice count
(so-called Gessel walks) is algebraic. This result is interesting not
only for combinatorial reasons but also from the viewpoint of symbolic
computation, as it would have been impossible to do the job without the
use of efficient implementations of efficient algorithms on efficient
hardware.

In the talk, we will explain the kernel method and discuss typical
combinatorial situations in which it is applicable. Then we describe how
computer algebra can prove combinatorial theorems based on the kernel
method and point out which computational difficulties may arise in this
context.
","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qrh8te7pi05a62ch1jptcucffs","2010-01-07 10:35:53","2010-01-19 21:05:47"
"624","14","Spring Departmental Meeting Tea and Cookies","2010-01-11 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pf3c463i24dpqe9342f2l0fvik","2010-01-08 17:27:38",NULL
"625","14","Spring Departmental Meeting","2010-01-11 16:00:00",NULL,"SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jirghm134rv6jm44vfki8421sk","2010-01-08 17:28:31",NULL
"626","2","Diophantine Numbers in Dynamics","2010-01-20 16:00:00",NULL,"SAS 4201","Yitwah Cheung",,"San Francisco State University",,,"Irrational numbers may be classified in terms of how well they can be approximated by rationals. On one end of the spectrum we have ""badly approximable"" numbers, which include all quadratic irrationals (the golden mean, in particular) while on the other end we have Liouville numbers, named after the mathematician who first used them to construct transcendental numbers.  In this talk I will describe how some of these notions crop up in the study of dynamical systems, often unexpectedly.  I will also explain how the theory of dynamical systems helps us better understand the theory of Diophantine approximation, especially in higher dimensions.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j6jfppad2ieas7opl49jatd4vk","2010-01-14 10:59:55","2010-01-15 14:16:33"
"627","6","Localized Optimization: Exploiting non-orthogonality to efficiently minimize the Kohn-Sham Energy","2010-02-08 03:00:00",NULL,"SAS 4201","Marc Millstone","http://www.cims.nyu.edu/~marcm/","Courant Institute NYU","Tim Kelley",,"With the constantly increasing power of computers, the realm of experimental chemistry is increasingly being brought in contact with the field of computational mathematics.  In particular, the ability to compute the charge density, i.e., the probabilistic location of a molecule's electrons, allows numerous properties of matter to be displayed graphically, as opposed to investigated in the chemistry lab.
As many current methods scale at a rate proportional to the cube of the number of atoms, such problems are still too large for direct {\it ab initio} computations.  This work describes a new algorithm for minimizing the Kohn-Sham energy that not only avoids local minima, but also guarantees the expensive energy function is only evaluated at sparse iterates. Preliminary results on a realistic model problem as well as small 
molecular systems will be given.
","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cjaj9nhj80d40nsvqigvejhols","2010-01-18 15:16:54",NULL
"628","4","Hydrodynamic Instability of Homogeneous and Inhomogeneous Viscous Liquids in a Rotating Tilted Tank","2010-02-24 15:00:00",NULL,"SAS 4201","Thomas Ward","http://www.mae.ncsu.edu/homepages/ward/","NC State Mechanical and Aerospace Engineering","Mark Hoefer",,"A tilted-partially filled rotating tank is studied experimentally at small < 1 and O(1) Reynolds and small < 1 capillary numbers, to study mixing of a viscous homogeneous fluid. Of particular interest is the transition from the low Reynolds number flow, that exhibits two large vortices, to the laminar flow regime which results in additional vortex generation. In the low Reynolds number (¡¡1) limit, a nonlinear analysis (Ward & Metchik, Chem. Engng. Sci., 2007) predicted that the two vortex generation case and rate of mixing are possibly generated by a periodic shear type instability (Franjione & Ottino, Trans. Phil. R. Soc., 1992). As the Reynolds number increases to the laminar regime, the two vortices show some interactions with the bottom cylindrical wall and begin a cascading effect that is similar to the well known Moffatt (J. Fluid Mech., 1964) vortices in Stokes flow in cavities. The additional vortices aid in trans- porting material from the liquid rotation axis, and the walls, to the bulk of the region between them. But the vortices also intensify in magnitude with increasing rotation rate leading to the appearance of KAM surfaces, which are barriers to efficient mixing. Experiments are performed using a 90% glycerol/water mixture at two volume portions with angles ranging between 25&#9702; to 65&#9702; measured from thee horizontal. Laser fluorescence is used to illuminate the vortices via experimental Poincaré mapping (Fountain, Khakhar & Ottino, Science, 1998), and the resulting images are analyzed to determine the mixed cross sectional area versus elapsed time. If time permits some new results for mixing inhomogeneous fluids will be presented.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mlkang92o55ptr316tnv7ni948","2010-01-18 18:13:16","2010-02-19 09:35:01"
"629","14","Departmental Tea and Cookies","2010-01-20 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/o8r45fs07dheg10cll7mg3vnr0","2010-01-19 10:23:22",NULL
"630","7","Climate response and fluctuation-dissipation theorem","2010-02-15 15:00:00",NULL,"SAS 4201","Boris Gershgorin","http://www.cims.nyu.edu/~borisg/","New York University","Min Kang",,"The fluctuation-dissipation theorem (FDT) provides an attractive
perspective to address climate change in an atmosphere-ocean system (AOS). The theorem states that in order to predict the linear response of a dynamical system in equilibrium to a small perturbation in external forcing, it is sufficient to find the appropriate correlation function in equilibrium without the need for perturbing the system. An attractive feature of applying the FDT to low-frequency climate variables of an AOS is that the linear response operator computed by the theorem can then be utilized for multiple climate change scenarios without the need of running the complex climate model in each individual case.
In this talk, we focus on the performance of FDT and its approximations in predicting climate change in idealized models. On the one hand these models are simple enough to be solved either analytically or numerically and on the other hand they mimic some of the key properties of a complex AOS. In particular, we consider three different nonlinear test models that allow us to investigate such important practical issues of assessing climate change via FDT as the performance of linear regressions, the subtle departures from Gaussianity and the time-dependent statistics in the model. The results of our study should provide useful guidelines for applying the FDT to more complex realistic systems.  

(This is joint with Differential Equations seminar)","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ai37rs7251ovhccgebmdlug818","2010-01-19 14:07:49","2010-02-12 11:13:26"
"631","8","Shallow Circuits with High-Powered Inputs","2010-03-17 15:00:00",NULL,"SAS 1218","Pascal Koiran",," Ecole Normale Supérieure de Lyon","Erich Kaltofen",,"A polynomial identity testing algorithm must determine whether an input polynomial (given for instance by an arithmetic circuit) is identically equal to 0.
Following Kabanets and Implagliazzo (2004), it has become increasingly clear in recent years that efficient deterministic algorithms for polynomial identity testing would imply strong lower bounds (the connection between arithmetic circuit lower bounds and derandomization of polynomial identity testing was foreshadowed in a 30 years old paper by Heintz and Schnorr). This approach to lower bounds was advocated in particular by Agrawal (2005).
In my talk I will present some further results on univariate polynomial identity testing.
I will highlight three open problems which can  be viewed as refinements
of the  tau-conjecture of Shub and Smale  on integer roots of univariate polynomials.
In particular, I will propose a real version of the tau conjecture.
A positive answer to any of these three problems would imply a superpolynomial lower bound on the arithmetic complexity of the permanent polynomial.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0m9il1gmei8k63lsiv0v8q4guk","2010-01-19 22:32:32","2010-02-02 11:00:30"
"633","2","Total positivity in loop groups","2010-01-28 16:00:00",NULL,"SAS 4201","Pavlo Pylyavskyy",,"University of Michigan",,,"The Edrei-Thoma theorem characterizes totally positive functions, and plays an important role in character theory of the infinite symmetric group. The Loewner-Whitney theorem characterizes totally positive elements of the general linear group, and is fundamental for Lusztig's theory of total positivity in reductive groups. In this work we derive a common generalization of the two theorems. The talk is based on joint work with Thomas Lam.

Dr. Pylyavskyy is a candidate for an Assistant Professorship in the Department of Mathematics.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dif70fbkl2979fkkv64uojip1s","2010-01-21 14:40:16",NULL
"634","22","Reflection groups, root systems, and singularities","2010-01-27 16:00:00",NULL,"SAS 2102","Bojko Bakalov",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/012710.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m8b1ofb0pekcjqqptip45r6mlk","2010-01-22 13:14:46",NULL
"635","22","Cards, Codes, and Kangaroos","2010-02-03 16:00:00",NULL,"SAS 2102","Lindsey Bosko",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/020310.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rmull73om6dijl0mtrtbuqbdk8","2010-01-22 13:37:47",NULL
"636","22","An Introduction to Coding Theory","2010-03-10 16:00:00",NULL,"SAS 2102","Nephi Noble",,"National Security Agency",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/031010.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b8vomn6sokbjn2j1ej6dgos2ec","2010-01-22 13:38:36","2010-03-08 09:47:47"
"637","22","p-adic numbers and p-adic analyses","2010-03-24 16:00:00",NULL,"SAS 2102","Loek Helminck",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/032410.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b2hdgrkfjafrbasaj3ov754ao4","2010-01-22 13:39:42","2010-03-23 09:17:53"
"639","14","Departmental Tea and Cookies","2010-01-28 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/4mkev9j1cggf63vfo6ht0o8o5k","2010-01-25 10:56:36","2010-01-25 11:14:09"
"640","14","Departmental Tea and Cookies","2010-01-29 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/456ta1g9kc22nvtppb0s3nkd68","2010-01-25 10:57:06","2010-01-25 11:14:32"
"641","2","Group Representation Patterns in Digital Signal Processing","2010-01-29 15:00:00",NULL,"SAS 4201","Shamgar Gurevich",,"IAS, Princeton",,,"In the lecture I will explain how various fundamental structures from group representation theory appear naturally in the context of discrete harmonic analysis and can be applied to solve concrete problems from digital signal processing. I will begin the lecture by describing our solution to the problem of finding a canonical orthonormal basis of eigenfunctions of the discrete Fourier transform (DFT). Then I will explain how to generalize the construction to obtain a larger collection of functions that we call ""The oscillator dictionary"". Functions in the oscillator dictionary admit many interesting pseudo-random properties, in particular, I will explain several of these properties which arise in the context of problems of current interest in communication theory.

Dr.  Gurevich is a candidate for an Assistant Professorship in the Department of Mathematics.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p3ef1hafsboj7ppss0b1a7b3m4","2010-01-25 12:05:15","2010-01-25 12:55:11"
"642","7","Synchronous Dynamics of a Stochastically Driven Neuronal Network Model","2010-03-08 15:00:00",NULL,"SAS 4201","Peter Kramer","http://www.rpi.edu/~kramep/","Rensselaer Polytechnic Institute","Min Kang",,"We study networks of identical excitatory integrate-and-fire neurons
driven by an external spike train modeled as a Poisson process.
Numerical simulations demonstrate that over a broad range of
parameters, the network enters a synchronized state in which the
neurons all fire together at regular intervals.  We identify
mechanisms leading to this synchronization for two regimes of the
external driving current: superthreshold and subthreshold.  In the
former, a probabilistic argument similar to the proof of the Central
Limit Theorem yields the oscillation period, while in the latter, this
period is analyzed via an exit time calculation utilizing a diffusion
approximation of the Kolmogorov forward equation.  In both cases,
stochastic fluctuations play a central role in determining the
oscillation period.  We also develop a criterion for synchrony in the
network through a probabilistic argument, which we apply to an
all-to-all network and a scale-free network model. This work is in
collaboration with Katherine Newhall, Gregor Kovacic, David Cai, and
Max Shkarayev.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v71oqi77u53t6i80fei8njk3to","2010-01-26 13:36:45","2010-03-03 10:50:47"
"643","7","Nonuniqueness for Some Stochastic PDE","2010-03-22 15:00:00",NULL,"SAS 4201","Carl Mueller","http://www.math.rochester.edu/people/faculty/cmlr/","University of Rochester","Min Kang",,"The superprocess is one of the most widely studied models in
probability.  It arises as a  limit of population processes which
depend on space as well as time.  One long-standing question involves
the uniqueness of the stochastic PDE which describes the superprocess.
Due to randomness, standard results about uniqueness of PDE do not
apply.  We will describe joint work with Barlow, Mytnik, and Perkins,
in which we prove nonuniqueness for the equation describing the
superprocess.  Our results generalize to several related equations.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b1ec2705eqffmap52hpj517hcc","2010-01-26 15:30:56","2010-02-24 11:23:33"
"644","2","The Calderon Problem - From the Past to the Present","2010-02-02 16:00:00",NULL,"SAS 4201","Leo Tzou",,"Stanford University","Ralph Smith",,"The problem of determining the electrical conductivity of a body by making voltage and current measurements on the object's surface has various applications in fields such as oil exploration and early detection of malignant breast tumour. This classical problem posed by Calderon remained open until the late '80s when it was finally solved in a breakthrough paper by Sylvester-Uhlmann. In the recent years, geometry has played an important role in this problem. We will look at the connection between this analysis problem with seemingly unrelated fields such as symplectic geometry and differential topology as well as geometric scattering theory.  The speaker is partially supported by NSF Grant No. DMS-0807502.

Dr. Tzou is a candidate for an Assistant Professorship in the Department of Mathematics.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cvgpa6s68eoj3nft0gb28e9nqc","2010-01-26 15:57:22",NULL
"647","7","Self-similarity and eternal solutions for a model of min-driven clustering","2010-02-01 15:00:00",NULL,"SAS 4201","Robert Pego","http://www.math.cmu.edu/~bobpego/","Carnegie Mellon","Min Kang",,"Joint seminar between probability seminar and differential equations seminar. 

A simple model of 1D coarsening dynamics in the Allen-Cahn equation is a 'one-dimensional bubble bath' which coarsens by two simple rules:  (i) The two nearest domain walls 'pop', annihilating each other.  (ii) Repeat indefinitely.  We study mean-field models for a class of 'min-drive' clustering processes of this kind.  By extending a remarkable solution procedure found by Gallay and Mielke, and using the sharp exponential Tauberian theorem of de Haan, we establish:  a well-posedness theorem for measure-valued size distributions; necessary and sufficient conditions for approach to self-similar form; and a Levy-Khintchine representation formula for eternal solutions.  This is joint work with Govind Menon and Barbara Niethammer.

","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8mahi43n0sutdrpvn6s6rmgg9g","2010-01-27 11:38:38","2010-01-27 14:13:52"
"649","4","Capturing stochastic contributions in noise systems","2010-02-18 15:00:00",NULL,"SAS 4201","Alexandros Sopasakis","http://math.uncc.edu/~asopasak/AlexandrosSopasakis/Alexandros%20Sopasakis.html","UNC Charlotte","John Harlim",,"We introduce and study a class of model prototype hybrid systems, with
multiscale coupling which essentially describe a wide range of physical
applications. The challenge in these hybrid problems is two fold:
a) The direct numerical simulation of realistic size systems due to
scale disparities between the discrete stochastic microscopic model and
the continuum macroscopic equations.
b) The stochasticity inherited from the microscopic model can play a
subtle but important role in the dynamic behavior of the overall system
due to the nonlinear interaction of the coupling.
In this work we address directly or indirectly both issues in the context
of proposed prototype mathematical models of a deterministic ODE coupled
with a stochastic spin flip / spin exchange Ising model that capture
essential features of complex hybrid systems.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1bf6v7ap81l2n5q5knjbiibc6s","2010-01-27 13:08:27","2010-02-09 08:03:16"
"650","4","Climate response and fluctuation-dissipation theorem","2010-02-15 15:00:00",NULL,"SAS 4201","Boris Gershgorin","http://www.cims.nyu.edu/~borisg/","Courant Institute, NYU","John Harlim",,"The fluctuation-dissipation theorem (FDT) provides an attractive
 perspective to address climate change in an atmosphere-ocean system
 (AOS). The theorem states that in order to predict the linear response of a
 dynamical system in equilibrium to a small perturbation in external
 forcing, it is sufficient to find the appropriate correlation function
 in equilibrium without the need for perturbing the system. An attractive
 feature of applying the FDT to low-frequency climate variables of 
 an AOS is that the linear response operator computed by the 
 theorem can then be utilized for multiple climate change scenarios
 without the need of running the complex climate model in each
 individual case. In this talk, we focus on the performance of FDT 
 and its approximations in predicting climate change in idealized 
 models. On the one hand these models are simple enough to be 
 solved either analytically or numerically and on the other hand they 
 mimic some of the key properties of a complex AOS. In particular, 
 we consider three different nonlinear test models that allow us to 
 investigate such important practical issues of assessing climate 
 change via FDT as the performance of linear regressions, the 
 subtle departures from Gaussianity and the time-dependent 
 statistics in the model. The results of our study should provide 
 useful guidelines for applying the FDT to more complex realistic 
 systems.

(Joint with Probability Seminar)","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2o7144s263u1n9tb6p1g1teuf4","2010-01-27 13:10:05","2010-01-27 14:16:27"
"651","4","Collapsing and Explosion Waves in Phase Transitions and Their Implications","2010-03-10 15:00:00",NULL,"SAS 4201","Haitao Fan","http://www9.georgetown.edu/faculty/fanh/","Georgetown University","Xiao-Biao Lin",,"In flows involving liquid/vapor phase transitions, there are liquefaction waves and evaporation waves. Subsonic phase changing waves are known to exist. Recently, in a joint work with Xiaobiao Lin, we established the existence of supersonic phase changing waves, called collapsing waves and explosion waves. One side of these waves is the equilibrium  liquid/vapor mixture while the other side is metastable liquid or vapor.
We gave the necessary and sufficient condition for the existence of collapsing waves, and the conditions for existence and non-existence of evaporation waves. The collapsing wave is identified as the front of rings observed in close-end shock tube experiments. These many supersonic and subsonic phase changing waves lead to nonuniqueness of  Riemann problems. To settle the nonuniqueness, we consider the stability of the phase changing traveling waves. The result explains the transition from slow to fast mode of condensation as pressure increases. If time permits, I will further discuss the liquid/vapor phase transitions in porous media.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e80ff2ic1572veugcte1grbjcc","2010-01-27 13:12:26","2010-03-04 22:27:35"
"652","4","Network dynamics of Hodgkin-Huxley neurons","2010-03-02 15:00:00",NULL,"SAS 4201","Yi Sun","http://www.cims.nyu.edu/~yisun/index.html","NC State Mathematics","Mark Hoefer",,"The reliability and predictability of neuronal network dynamics is a central question in neuroscience. We present a numerical analysis of the dynamics of all-to-all pulsed-coupled Hodgkin-Huxley (HH) neuronal networks. Since this is a non-smooth dynamical system, we propose a pseudo-Lyapunov exponent (PLE) that captures the long-time predictability of HH neuronal networks. The PLE can capture very well the dynamical regimes of the network. Furthermore, we present an efficient library-based numerical method for simulating HH neuronal networks. Our pre-computed high resolution data library can allow us to avoid resolving the spikes in detail and to use large numerical time steps for evolving the HH neuron equations. By using the library-based method, we can evolve the HH networks using time steps one order of magnitude larger than the typical time steps used for resolving the trajectories without the library, while achieving comparable resolution in statistical quantifications of the network activity. Moreover, our large time steps using the library method can overcome the stability requirement of standard ODE methods for the original dynamics.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cibj27nlflif7o00basssg9kto","2010-01-27 17:19:35","2010-02-04 10:19:01"
"653","7","WHICH STATE IS THE BEST SINK","2010-04-12 15:00:00",NULL,"SAS 4201","Leonid Bunimovich","http://people.math.gatech.edu/~bunimovh/","Georgia Institute of Technology","Min Kang",,"A natural question on how the survival probability depends upon a position of a hole was seemingly never addressed in the theory of open dynamical systems.
A dynamical system is open if in its phase there is a subset (hole) where the orbits disappear upon hitting it. Usually statistical properties of dynamical systems are proved by strengthening in some way the results from the probability theory. However the problem in question was not considered even in the theory of Markov chains. Answering it one gets a new information on hiting time distribution in Markov chains which is concerned with the distribution of hitting time rather than classical results on average hitting times.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/njvl6vuklft82vhblv634vhua4","2010-01-28 09:10:58","2010-03-19 16:29:55"
"654","14","Departmental Tea and Cookies","2010-02-02 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fbglucqatbb71fbm0gbrpfnb5k","2010-02-01 07:40:54","2010-02-01 07:41:39"
"655","8","Holographic algorithms without matchgates","2010-02-17 15:00:00",NULL,"SAS 1218","Jason Morton",,"Penn State University",,,"Combinatorial (weighted) counting problems, such as counting the
number of satisfying assignments of a Boolean satisfiability problem
or computing the partition function of a graphical model, can be
expressed as tensor contractions diagrammed by a bipartite graph
$\Gamma=(V,U,E)$. Many algorithms for solving these problems
efficiently use tree structure and factorization over a semiring (the
""sum-product algorithm""). Over a proper ring, cancellation can be
exploited as well. This requires a change of basis so that the
Grassmann-Plucker identities are locally satisfied, and the addition
of orientation or ordering information. Recently, this Pfaffian-based
approach has been used by Valiant and Cai to provide unexpected,
polynomial-time ""accidental"" algorithms for certain counting problems.
Their method expands the vertices of $\Gamma$ into graph fragments
called matchgates and applies the FKT algorithm to find a Pfaffian
orientation and compute the perfect matching polynomial. We
demonstrate a simplification of this approach using only a $|E| \times
|E|$ matrix and give some generalizations. Natural problems treatable
by these generalizations have been previously considered in a different
context, and we present one such example. This is joint work with
J.M. Landsberg and Serguei Norine.  http://arxiv.org/abs/0904.0471","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6e109b9t2cpfgab9135kdsr6jg","2010-02-01 11:21:03","2010-02-13 07:50:44"
"656","6","Network dynamics of Hodgkin-Huxley neurons","2010-03-02 15:00:00",NULL,"SAS 4201","Yi Sun","http://www.cims.nyu.edu/~yisun/index.html","NC State","NA Seminar",,"The reliability and predictability of neuronal network dynamics is a central question in neuroscience. We present a numerical analysis of the dynamics of all-to-all pulsed-coupled Hodgkin-Huxley (HH) neuronal networks. Since this is a non-smooth dynamical system, we propose a pseudo-Lyapunov exponent (PLE) that captures the long-time predictability of HH neuronal networks. The PLE can capture very well the dynamical regimes of the network. Furthermore, we present an efficient library-based numerical method for simulating HH neuronal networks. Our pre-computed high resolution data library can allow us to avoid resolving the spikes in detail and to use large numerical time steps for evolving the HH neuron equations. By using the library-based method, we can evolve the HH networks using time steps one order of magnitude larger than the typical time steps used for resolving the trajectories without the library, while achieving comparable resolution in statistical quantifications of the network activity. Moreover, our large time steps using the library method can overcome the stability requirement of standard ODE methods for the original dynamics.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ajq35n3rkt583lsm992ire41ic","2010-02-04 13:19:37","2010-03-01 11:41:05"
"658","22","Knots, Surfaces and the Fundamental Group","2010-02-10 16:00:00",NULL,"SAS 2102","Nathan Reading","http://www4.ncsu.edu/~nreadin","NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/021010.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pc9uqqidi8rc36kaekutjju4n0","2010-02-08 09:58:02","2010-02-08 15:18:38"
"659","22","Be an Actuary","2010-02-17 16:00:00",NULL,"SAS 2102","Norman Storwick",,"BlueCross BlueShield of NC",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/021710.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jm91g42v6joejsphpoph27bqn0","2010-02-08 15:14:31","2010-02-15 15:36:35"
"660","22","TBA","2010-02-24 16:00:00",NULL,"SAS 2102","Sandra O. Paur",,"NC State",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/571qvu0fvkbs2f07q7oqnmg0q0","2010-02-08 15:15:29",NULL
"661","22","The Mathematics of Phylogenetic Trees","2010-04-07 16:00:00",NULL,"SAS 2102","Megan Owen",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum","An evolutionary, or phylogenetic, tree represents the evolutionary history of a set of organisms, like the fungi or the marsupials.  Phylogenetic trees are usually constructed from DNA sequences for genes.  But what happens when two different genes suggest two different evolutionary histories?  In this talk, we'll look at ways to quantitatively compare two trees, describe a mathematical space of trees, and show how these ideas could be used to reconcile gene trees.  This talk will be accessible to all undergraduates, and no knowledge of biology is assumed.","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a4kd7a08ceitbsuh8rpecqekio","2010-02-08 15:16:36","2010-04-05 07:34:39"
"662","14","Departmental Tea and Cookies","2010-02-10 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/snu4k5rtkok6t9cvd462agt5vc","2010-02-09 11:28:59",NULL
"663","6","Overcoming the Gibbs Phenomenon Using a Modified Radial Basis Functions Method","2010-03-09 15:00:00",NULL,"SAS 4201","Cécile Piret","http://www.asp.ucar.edu/pdfp/postdocs/C.Piret.php","NCAR","Mark Hoefer",,"The Radial Basis Functions (RBF) method is not immune from
the disastrous effects of the Gibbs phenomenon. When interpolating or
solving PDEs whose solutions are piecewise smooth functions, the RBF
method loses its notorious spectral accuracy. In this talk, a new
method will be presented, based on the RBF method, which incorporates
singularities using Heaviside functions and which keeps track of their
location using the level set method. The resulting sharp interface
method will be shown to recover the lost spectral accuracy and thus
overcome the Gibbs phenomenon altogether.
","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tr2eb4hkcrq097ek1ftj0qc5qs","2010-02-11 09:50:19","2010-02-11 10:10:22"
"664","14","Joel Cason Going Away Party","2010-02-24 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hod4gdm56pcrj1gja8rkffosrc","2010-02-11 13:35:31",NULL
"665","1","Climate Change: Can Mathematics Help Clear the Air?","2010-03-04 16:00:00",NULL,"SAS 1102","Christopher Jones","http://www.math.unc.edu/Faculty/jones","University of North Carolina at Chapel Hill","Steve Schecter",,"There is a consensus in the scientific community that the climate is changing due to anthropogenic forcing. But there is less indication in the mathematical community that we are ready, or know how, to get involved in climate research. I will argue that we have a critical role to play, and will lay out a series of important questions that require mathematics.
","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/psnbl37vr5kg7pc1auc5r70og0","2010-02-11 14:49:54","2010-02-25 09:39:13"
"666","3","Complexity and structure of indecomposable injective modules over a noetherian ring","2010-04-23 16:00:00",NULL,"SAS 4201","Thomas Kucera","http://server.maths.umanitoba.ca/homepages/tkucera.html/index.html","University of Manitoba, Winnipeg, Canada",,,"This is a talk more about problems than results. I will discuss a strong dichotomy between two points of view of the problem of the title. One, arising primarily from model theory (mathematical logic) is that it is too simple a question to be of much interest; the other, arising primarily from non-commutative localization theory, is that it is too difficult to be feasible without extra assumptions.

The classic theorems of Matlis [1958] completely solve the question for commutative noetherian rings. But almost nothing from these results carry over in complete generality even to non-commutative noetherian rings, never mind to rings which are noetherian on one side only.

I have been for some time exploring the elementary socle series of a module, introduced by Ivo Herzog in 1992. This concept from the model theory of modules may provide a method for attacking the seemingly intractable algebraic problems concerning the structure of indecomposable injective modules over a non-commutative noetherian ring, and answer some questions about how complicated these modules really are.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5cpliiugodu9g5pvvuo6hit3f0","2010-02-12 13:21:45","2010-03-24 18:07:51"
"667","3","Quantum affine Lie algebras and perfect crystals","2011-02-04 14:00:00",NULL,"SAS 4201","Kailash Misra","http://www4.ncsu.edu/~misra/","NC State",,,"Affine Lie algebras are the simplest infinite dimensional analogs of finite dimensional semisimple Lie algebras. Quantum affine algebras are q-deformations of universal enveloping algebras of affine Lie algebras. We can associate a combinatorial object called ""crystal"" with any integrable representation of a quantum affine Lie algebra. A perfect crystal is a crystal for certain finite dimensional representation of a quantum affine algebra with some nice properties. In 1990's it was proved that the crystal for any integrable representation of a quantum affine algebra can be realized as a semi-infinite tensor product of a suitable perfect crystal.  In this talk I will discuss about a recently discovered perfect crystal for a rank two exceptional quantum affine algebra. I will try to make the talk as accessible as possible to graduate students.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gvi271p19ekufu6kncjk4keh48","2010-02-16 08:43:18","2011-01-01 12:07:49"
"668","3","Cutting a square into triangles","2010-05-14 16:00:00",NULL,"SAS 4201","Aaron Abrams",,"Emory University",,,"Suppose you are given an abstract triangulation T of a square, and you want to realize it in the plane as a triangulation of the unit square.  What are the possibilities for the areas of the triangles?  It turns out that the areas must satisfy a polynomial relation p(T), which depends on the combinatorics of T.  I will talk about preliminary attempts to understand the polynomial p(T).  This is joint work with Jamie Pommersheim.
","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t8udheiepl79ndgm1aj5uito10","2010-02-16 08:44:04","2010-05-06 16:47:53"
"669","14","Departmental Tea and Cookies","2010-02-17 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/v0mlnm4m7gm89sven7i5lskqgg","2010-02-16 15:11:38",NULL
"670","8","Sums of Squares, Nonnegative Polynomials and Convex Algebraic Geometry","2010-03-24 15:00:00",NULL,"SAS 1218","Greg Blekherman",,"Virginia Tech",,,"We will  study the sets of nonnegative polynomials and sums of squares (SOS) from the point of view of convex geometry. This approach provides insights into the relationship between these sets that seem to be otherwise unavailable.

We will show how to use volumes to prove that there exist (many) convex forms that are not sums of squares and that there are significantly more nonnegative polynomials than SOS. There are currently no known explicit convex forms that are not sums of squares.

Studying boundary structure, we will explain how to establish large dimensional differences between faces of the cone of nonnegative polynomials and the cone of sums of squares. These dimensional differences can be exploited to produce explicit faces of the SOS cone that pass through the interior of the cone of nonnegative polynomials. In particular this allows us to build strictly positive polynomials that are not SOS.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0nts81mrgrbq15o5t6oiso1oe0","2010-02-17 10:19:53","2010-03-06 21:25:21"
"671","15","SIAM Student Chapter Business Meeting","2010-02-24 15:30:00",NULL,"SAS 2106",,,,"SIAM Student Chapter",,,"klrehm","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s1methd6mml4qmggo6rcj5ne6s","2010-02-18 08:43:14",NULL
"672","14","Undergraduate Pre-Colloquium: Game Theory and Climate Change Negotiations","2010-03-04 14:20:00",NULL,"SAS 4201","Stephen Schecter","http://www4.ncsu.edu/~schecter/","NC State",,,"The governments of the world agree that humans are causing changes to the earth's climate that will lead to enormous problems for civilization, but they are unable to agree to do anything about it.  Can game theory illuminate why climate change negotiations are so difficult?  Participants will play a series of simple games that illustrate some of the problems.

This event will be followed by tea in the Mathematics Commons at 3:30 and then by Chris Jones's colloquium talk about climate change at 4 p.m.
","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7emqkiibv2mbvc2g61mjl7v450","2010-02-18 09:30:52",NULL
"673","22","Young Diagrams and Young Tableaux","2010-03-03 16:00:00",NULL,"SAS 2102","Laurie Zach",,"High Point University",,"http://www4.ncsu.edu/~nreadin/sum/spring2010/030310.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o9ndf2jun849haqh8ittvn9qik","2010-02-18 10:04:00",NULL
"674","22","CSI on the water","2010-04-21 16:00:00",NULL,"SAS 2101","Miles A. Beam, P.E.","http://www.boatcrash.com/",,,"http://www4.ncsu.edu/~nreadin/sum/spring2010/042110.pdf","When two boats collide in the middle of the night, and nobody saw it happen, how does one determine what actually happened?  Mr. Miles Beam, P.E., has the unique task of answering that question.  Miles had the opportunity of pioneering the research necessary to develop techniques to reconstruct boat collisions based on physical evidence, primarily an analysis of the collision damage to each vessel.  Graduating from NCSU in 1985, with a BS in Mechanical Engineering, Miles serves today as an independent consultant in the marine accident reconstruction field.  His clients include state governments, the US federal government, the government of Australia, boat and equipment manufacturers, insurance companies and law firms.  Miles has testified in court as an expert witness in both civil and criminal cases.

This talk will provide an overview of the applied mathematics and basic engineering principles involved in determining key characteristics of a boat collision, such as impact angle and the relative speeds of each vessel.  The talk will also include an overview of the accident reconstruction process and the use of related technologies, such as photogrammetry, 3d CAD modeling, and computer animation. It's CSI on the water!  Time permitting, a question and answer session will conclude the discussion.
","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oa3mgg5q7qd9ti929019b92m9c","2010-02-18 10:06:23","2010-04-05 16:31:35"
"675","4","Chaos and multivaluedness: travelling on Riemann surfaces","2010-04-14 15:00:00",NULL,"SAS 4201","Matteo Sommacal","http://www.researcherid.com/rid/C-3771-2008","University of Rome","Mark Hoefer",,"Recently, a mechanism to explain the onset of irregular (chaotic) motions in a dynamical system, in terms of the singularity structure of its solutions, was introduced. The dynamics defined by a certain (paradigmatic) set of three coupled (complex) first-order ODEs, featuring two coupling constants, will be illustrated. It is shown that the system under study can be reduced to quadratures which can be expressed in terms of elementary functions. Despite the integrable character of the model, the general solution is a multiple-valued function of time (considered as a complex variable), and we investigate the position and nature of its branch points. For rational values of the coupling constants, the system is isochronous and explicit formulae for the period of the solutions can be given. For irrational values, the system features confined and aperiodic motions. In this case, an argument is introduced to explain why sensitive dependence on initial conditions is expected. The system shows a rich dynamical behaviour that can be understood in quantitative detail since a global description of the Riemann surface associated with the solutions can be achieved. This toy model is meant to provide a paradigmatic first step towards understanding a (novel) mechanism leading to the onset of irregular (chaotic) behaviours for dynamical systems.
This work has been carried out in collaboration with F. Calogero and P. M. Santini of the Università degli Studi di Roma ""La Sapienza"" (Italy) and D. Gomez-Ullate Oteiza of the Universidad Complutense de Madrid (Spain).
 
References:
[1] F. Calogero, D. Gomez-Ullate, P. M. Santini and M. Sommacal, The Transition from Regular to Irregular Motions, Explained as Travel on Riemann Surfaces, J. Phys. A 38, 8873-8896 (2005).
[2] F. Calogero, D. Gomez-Ullate, P. M. Santini and M. Sommacal, Towards a Theory of Chaos Explained as Travel on Riemann Surfaces, J. Phys. A 42, 015205 (2009).","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/95bn96cmqoloj1fhq4guo2spso","2010-02-22 16:01:49","2010-03-15 15:44:15"
"676","14","Departmental Tea and Cookies","2010-03-04 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/16mumjvi3igtiar1vl2nd0bias","2010-03-01 11:40:03",NULL
"677","6","Optimization-based closures for radiative transport","2010-03-23 15:00:00",NULL,"SAS 4201","Cory Hauck","http://www.csm.ornl.gov/~hfd/","Oak Ridge National Laboratory",,,"In this talk, I will present two new moment closures for solving
radiative transport equations. These closures modify the traditional spherical harmonic closure, which is known to produce non-physical oscillations in the kinetic distribution and even negative values for the particle concentration. The first
closure is derived from the solution to a constrained, quadratic optimization problem. The second closure uses a standard filter which is derived from an unconstrained, quadratic optimization problem but includes derivative information in the cost functional. Preliminary comparisons with current methods will be given.
","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vnoheiu31sm7lffbrjdbn6cefc","2010-03-04 13:15:41","2010-03-04 13:31:10"
"678","8","A Combinatorial Topological Toolkit for Stratified Spaces","2010-03-10 15:00:00",NULL,"SAS 1218","Patricia Hersh",,"NCSU",,,"There are quite a few stratified spaces, i.e. spaces made of pieces each
homeomorphic to $R^n$ for some n, of current interest in such areas as
combinatorial representation theory, (real) Schubert calculus, algebraic
statistics, and total positivity theory, the last of which are closely
related to the theory of canonical bases.  A common feature of these
spaces is that they may often be regarded as the image of a map from a
much more easily understood space of parameters.  I will discuss some
recently developed tools  for determining topological structure of such
spaces in a rather strong sense, namely homeomorphism type.  This will
include topological collapsing lemmas as well as a new criterion for
determining whether a finite CW complex is regular with respect to a
choice of characteristic maps.  While the proofs are topological, using
these tools can be essentially combinatorial, as I will illustrate on an
example.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tsjgh1gevesqn067r0lo1khba8","2010-03-08 10:02:08","2010-03-08 11:08:41"
"679","14","Departmental Tea and Cookies","2010-03-10 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9fdhffrukpe7eknsv2ttal4pi0","2010-03-08 10:26:45",NULL
"680","3","Finite-dimensional representations of quantum affine algebras at roots of unity","2010-03-26 16:00:00",NULL,"SAS 4201","Dijana Jakelic","http://people.uncw.edu/jakelicd/","UNC Wilmington",,,"The category of finite-dimensional representations of quantum affine algebras is not a semisimple category, however its simple objects are highest-weight in an appropriate sense. For generic values of the quantization parameter,  results of Chari and Kashiwara provide a useful way of obtaining indecomposable objects by giving sufficient conditions for a tensor product of simple objects to be highest-weight. In particular, a tensor product of fundamental representations can always be reordered in such a way that these conditions are  satisfied. This property turned out to be one of the essential ingredients used to describe the block decomposition of the category.

In this talk, we will focus on a joint work with A. Moura where we consider the root of unity case. We prove an analogue of Chari's version of the aforementioned result on tensor products of simple modules. However, the result about tensor products of fundamental representations is no longer valid. After reviewing the basics on finite-dimensional representations of quantum affine algebras, we will discuss the techniques we used to overcome this issue for describing the blocks in the root of unity setting.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ggngk96ljgacfpan02jbe0vrtg","2010-03-12 21:44:28",NULL
"681","14","Departmental Tea and Cookies","2010-03-24 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hf5ja6qf6p1rkiqid2sdg8t2gs","2010-03-22 14:25:58","2010-03-22 14:26:33"
"682","3","Phylogenetic algebraic geometry and the Verlinde formula.","2010-04-30 16:00:00",NULL,"SAS 4201","Chris Manon",,,,,"Recent work of Sturmfels and Xu establishes an intriguing connection between the Hilbert functions of important varieties from phylogenetic algebraic geometry and a special case of the celebrated Verlinde formula from mathematical physics.  We will show how to construct and generalize this relationship using the representation theory of Kac-Moody algebras, and discuss consequences for the commutative algebra of Cox rings of moduli of parabolic principal bundles.
","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ge5ol305rk7t1pf8rq30jrqafo","2010-03-24 17:46:06","2010-04-15 15:53:03"
"683","14","Departmental Tea and Cookies","2010-03-31 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/iq4brh4fvstrke4i46kfov1758","2010-03-29 10:13:25",NULL
"684","14","Departmental Tea and Cookies","2010-04-07 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mhg981nkmabcler5ui1gn32nbo","2010-04-05 10:58:05",NULL
"685","14","Graduate Student Meeting with Georgia Benkart","2010-04-13 15:00:00",NULL,"SAS 1102",,,,"Kailash Misra",,"Georgia Benkart, Professor Emeritus at the University of Wisconsin and president of the Association for Women in Mathematics (AWM), will meet informally with interested graduate students to discuss the AWM. ","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/08l8gb0p95klti9pcrjo7pa4gk","2010-04-05 11:21:52","2010-04-05 15:25:02"
"686","1","Travels to Hyperbolic Space Starting from an sl(2) Base","2010-04-13 16:00:00",NULL,"SAS 1102","Georgia Benkart",,"University of Wisconsin","Kailash Misra",,"Chevalley's basis for simple Lie algebras has been the preferred basis choice for over a century, and it has given much insight into the structure and representations of Lie algebras. This talk will focus on the smallest simple Lie algebra, sl(2), of 2 x 2 matrices of trace zero and a different choice of basis, which will take us to hyperbolic space, with stops along the way at interesting lattices and interesting groups such as the modular and braid groups. This basis arose in a very natural way in combinatorial investigations of association schemes.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/tfqcc7r4o3m0s9653nnsr6mb1c","2010-04-05 13:44:20","2010-04-05 15:23:50"
"687","27","US-China Summer School on Representation Theory","2010-07-12 08:00:00","2010-07-26 17:00:00","East China Normal University in Shanghai, China",,,,,"http://www4.ncsu.edu/~jing/conf/shanghai10.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mmc9j4gn6tkdatt91k9cv5mbds","2010-04-05 14:31:42",NULL
"688","8","Topology and Computational Complexity: a Real analogue of Toda's Theorem","2010-04-21 16:00:00",NULL,"SAS 1218","Thierry Zell",,"Lenoir-Rhyne University",,,"(Joint work with Saugata Basu.)

Toda proved in 1989 that the (discrete) polynomial time hierarchy, PH, is contained in the class P with advice from #P,  the class of languages that can be decided by a Turing machine in polynomial time given access to an oracle with the power to compute a function in the counting complexity class #P. We prove an analogous result in the complexity theory over the reals. Unlike Toda's proof in the discrete case, which relied on sophisticated combinatorial arguments, our proof is topological in nature, relying on a version of the descent spectral sequence which was previously used by Gabrielov, Vorobjov and the speaker to derive upper bounds on Betti numbers of semialgebraic projections and limits.

There are no real prerequisites necessary to enjoy the talk: all the relevant computational complexity notions and topological tools will be defined during the talk.

","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oerudip5amjircn92riifdjgfk","2010-04-06 11:22:11","2010-04-06 11:40:10"
"689","21","Thin Fluids Day","2010-04-17 09:45:00",NULL,"SAS 1108",,,,,"http://nile.physics.ncsu.edu/cgi-bin/webpage/News/50_thinfluids.html",,"schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5ijs46bcdaq0gohv3ge0bjkhso","2010-04-06 15:17:53","2010-04-15 11:25:32"
"690","27","Fluid Dynamics, Analysis, and Numerics 2010: a Conference in Honor of   J. Thomas Beale","2010-06-28 08:00:00","2010-06-30 17:00:00","Duke University in Durham, NC",,,,,"http://www.math.duke.edu/conferences/FAN2010/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jojerik1ffc25dk1sgi0djeh5k","2010-04-07 11:51:46",NULL
"691","27","SIAM / MSRI Workshop on Hybrid Methodologies for Symbolic-Numeric   Computation","2010-11-17 08:00:00","2010-11-19 17:00:00","Mathematical Sciences Research Institute in Berkeley, CA",,,,,"http://www.scg.uwaterloo.ca/siam-msri-hybrid",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/026n3jgg78jicp9ma1o3a30udo","2010-04-07 11:52:55",NULL
"692","21","NSF/CBMS Regional Conference on Quiver Varieties and Crystal Bases for Quantum Affine Algebras","2010-05-25 08:00:00","2010-05-29 17:00:00","NC State",,,,,"http://www4.ncsu.edu/~jing/conf/CBMS/cbms10.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0tc1a6hg2gie1gslri3jqsljbg","2010-04-07 22:05:38",NULL
"693","14","Awards Day Ceremony","2010-04-27 16:00:00",NULL,"SAS 1102",,,,,,"Please plan to attend and honor our outstanding undergraduate and graduate students.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p6895b5b8qbclmbnatnj84kbu4","2010-04-09 11:05:10",NULL
"694","14","Departmental Tea and Cookies","2010-04-27 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dgdusbn4v90ntp34uq7rt0ll88","2010-04-09 11:05:47",NULL
"695","15","Working at SAS as a Numerical Analyst","2010-04-14 15:30:00",NULL,"SAS 2106","Scott Pope",,"SAS","SIAM Student Chapter",,,"klrehm","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/07fij3dg4nl14a0fnkfd7defts","2010-04-12 10:42:09",NULL
"696","14","Departmental Tea and Cookies","2010-04-15 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vt94etj45q5lag8mrlan8uf9hk","2010-04-12 15:00:50",NULL
"697","14","Departmental Tea and Cookies","2010-04-13 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/iv7bopf5g83hvjg6bmorbqqsh8","2010-04-13 10:25:53",NULL
"698","27","6th International Workshop on the Numerical Solution of Markov Chains (NSMC) 2010","2010-09-16 08:00:00","2010-09-17 17:00:00","College of William & Mary in Williamsburg, Virginia",,,,,"http://www.cs.bilkent.edu.tr/%7Ensmc10/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/npaggd6t5alo3u3qgjscutavqg","2010-04-19 11:22:12","2010-08-06 10:37:37"
"699","14","Cancelled due to Shortage of Staff - Departmental Tea and Cookies","2010-04-21 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/t1c2qvtaq6447fd1ehcucsei3c","2010-04-19 11:47:53","2010-04-19 13:56:12"
"700","27","Householder Symposium XVIII on Numerical Linear Algebra","2011-06-12 08:00:00","2011-06-17 17:00:00","Granlibakken Conference Center & Lodge in Tahoe City, California",,,,,"https://outreach.scidac.gov/HH11/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oq3htko2ncatdofg5tpagutvqo","2010-04-25 11:33:32","2010-08-06 10:38:07"
"701","14","NC State Undergraduate Presentations","2010-04-28 16:00:00",NULL,"SAS 2102","Nicholas Yelle, Zach Clawson, and Joseph Briggs",,,,,"4:00 Nicholas Yelle: Random Walk Convergence to Brownian Motion

4:20 Zach Clawson: Nonlinear ODEs and Complementarity Problems

4:40 Joseph Briggs: Markov Chains and Black-Scholes Option Prices","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/akc5uhc9o7098oql4foaa0g1ss","2010-04-26 14:58:18",NULL
"702","14","NC State Undergraduate Presentations","2010-04-29 15:30:00","2010-04-29 17:00:00","SAS 2102","Mark Hunnell, Kelsey Hawkins, James Holbert, and Jonathan Bell",,,,,"3:30 Mark Hunnell: Topological Nets and Filters

3:50 Kelsey Hawkins: Foundations for Artificial Intelligence

4:10 James Holbert: Supermanifolds via Categories and Sheaves

4:30 Jonathan Bell: Integer Partitions","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/tt1m9tjc9n2nlnt5qstpu15hgs","2010-04-26 15:01:26",NULL
"703","27","MEGA 2011: Effective Methods in Algebraic Geometry","2011-05-30 00:00:00","2011-06-03 00:00:00","Stockholm, Sweden",,,,,"http://www.math.kth.se/mega2011/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/frq1tt5jfdr1dlpkoug1geiec4","2010-05-03 11:33:34",NULL
"704","27","Fourth International Workshop on Differential Algebra and Related Topics","2010-10-27 08:00:00","2010-10-30 14:00:00","Beijing, China",,,,,"http://mmrc.iss.ac.cn/~dart4/index.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f64rc0e1lq291uck4umabtcnec","2010-05-03 11:35:30",NULL
"705","2","Disjoint Homometric Sets in Graphs","2010-06-09 16:00:00",NULL,"SAS 4201","Michael Young",,"Smith College/Iowa State University",,,"Two sets of points, A and B are said to be homometric if the list
of distances between pairs of points in A is the same as the list of distances between pairs of points in B. The size and number of homometric sets of points on a cycle are well studied by crystallographers and music theorists. This talk will ask and discuss some questions about the size of homometric sets on other
types of graphs.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lr1viklk52jpfpcfb3rv3l5ui0","2010-06-07 12:08:20",NULL
"706","2","You and the American Statistical Association","2010-06-14 16:00:00",NULL,"SAS 4201","Sally Morton",,"RTI",,,"In this talk, I will address the importance of professional societies in the lives of mathematical scientists. I will discuss why and how you may get involved in a professional society, focusing on one society as an example – the American Statistical Association (ASA). I will also touch upon lessons learned (and being learned) in my career as an applied statistician.  ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lhdkqmvcmq8v8gdlhe316u4fn4","2010-06-07 12:09:09","2010-06-09 23:28:42"
"708","2","Counting Self-Intersections of Loops on Surfaces","2010-06-28 16:00:00",NULL,"SAS 4201","Patricia Cahn",,"Dartmouth Unversity",,,"Given a loop on a surface, we can count the number of times it crosses itself.  If we gradually deform the loop without lifting it from the surface, we may be able to remove some of those self-intersection points.  We would like to know how many self-intersection points cannot be removed by these deformations.  In this talk, we'll look at a method of computing this number which uses techniques from abstract algebra.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3jg9ndoflt602uo9evtk2rtl3c","2010-06-07 12:10:44",NULL
"709","14","Departmental Tea and Cookies","2010-06-09 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fk8m7ahm6tr5ja3fr90le7ori0","2010-06-07 12:12:15",NULL
"710","14","Departmental Tea and Cookies","2010-06-24 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b3kp2m61894f6l1u3vp01fht7g","2010-06-09 23:25:37",NULL
"711","14","Departmental Tea and Cookies","2010-06-16 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s0m96pa33keusd20v3f16dph24","2010-06-15 22:07:06",NULL
"712","14","Departmental Tea and Cookies","2010-06-23 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b433g349q1g3p16airlsqs4k5c","2010-06-15 22:07:41",NULL
"713","14","Departmental Tea and Cookies","2010-06-30 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ltr353crsso8u4i4hlvssb94ks","2010-06-15 22:08:09",NULL
"714","2","Mathematical Epidemiology: The Case of Influenza","2010-06-24 16:00:00",NULL,"SAS 1102","Carlos Castillo-Chavez and Joaquin Bustoz Jr.",,,,,"Disease dynamics are intimately connected to biological, environmental and social processes that take place at multiple temporal or spatial scales and over various levels of social/biological organization.  Despite the myriad of complexities associated with disease dynamics, macroscopic epidemic patterns emerge but finding effective ways of making use of this knowledge remain. Finding ways of integrating
and grasping the processes and patterns that take place at characteristic temporal scales and relevant levels of social and biological organization and applying this knowledge in the identification of timely and effective prevention or intervention
strategies are but some of the challenges addressed by the field of computational, mathematical and theoretical epidemiology. Some relevant specific questions include: How do we generate useful paradigms with the limitations inherent in reported
epidemiological data or with the challenges posed by unreported disease data or with the unreliability of surveillance systems?  Will evolutionary changes at lower levels of organization, like cross-immunity (e.g. in the case of influenza) alter
dramatically the epidemiological immunological profile of a population and if so how will this evolutionary changes impact disease dynamics? In this lecture I will address some of these challenges in a historical context starting with the work of physicians-theoreticians like Bernoulli, Ross, Kermack and McKendrick. The lecture will use examples from diseases like influenza. ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0p2hdhd3i4sqe03d9cvoei61f8","2010-06-23 09:28:31",NULL
"715","2","Cell lineages and feedback control in solid tumors","2010-06-30 14:00:00",NULL,"SAS 4201","John Lowengrub",,"University of California Irvine",,,"We have developed a multispecies continuum model to simulate the dynamics of cell lineages in solid tumors. The model accounts for spatiotemporally varying cell proliferation and death mediated by the heterogeneous distribution of oxygen and soluble chemical factors. Together, these regulate the rates of self-renewal and differentiation of the different cells within the lineages. Terminally differentiated cells release negative feedback factors (e.g., from the TGF superfamily of proteins)
that decrease rates of self-renewal and proliferation of less differentiated cells. Stem cells release a short-range positive feedback factor (e.g., Wnt), as well as a long-range inhibitor (e.g., Dkk). Under certain conditions, this results in the development of spatiotemporal heterogeneous chemical distributions and tumor cell populations with clusters of stem cells appearing at the tumor margin, consistent with recent experiments. The feedback processes are found to play a critical role in tumor progression and the development of morphological instability. For example, above a critical value of negative feedback response to the presence of a TGF protein, an initially spherical tumor evolves stably to a nearly stationary, spherically symmetric tumor shape. Below this threshold, instability occurs, the tumor develops invasive fingers and grows without bound, even in the absence of a vascular network. Further, resecting a stable tumor may upset the balance of feedback factors and lead to unstable growth. Therapeutic intervention by increasing the amount of TGF proteins in the system may arrest the growth of the tumor and may enable the tumor to extinguish itself. Stopping the therapy too soon may result in a dramatic increase in tumor instability.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5ak5qo2ui2e8kap51ug6gb7fe0","2010-06-28 22:45:04","2010-06-28 22:46:49"
"716","6","A Measure Theoretic Computational Approach for Inverse Sensitivity Problems","2010-11-05 15:00:00",NULL,"SAS 4201","Don Estep","http://www.math.colostate.edu/~estep/","Colorado State University","NA Seminar",,"We consider the inverse sensitivity analysis of a map from a set of
parameters and data to a quantity of interest. We are particularly
interested in implicitly-defined maps, e.g. involving the solution of
a differential equation. The inverse problem is to describe the random
variation in the input that leads to an imposed or observed random
variation in the output quantity. We formulate this as an ill-posed
inverse problem for an integral equation using the Law of Total
Probability. We then describe a computational method for computing
solutions that has two stages. In the first part, we approximate the
unique set-valued solution to the inverse of the integral equation
using derivative information. In the second part, we apply basic ideas
from measure theory to compute the approximate probability measure on
the parameter and data space that solves the integral equation. We
discuss convergence of the method, and explain how to use the method
to compute the probability of events in the input (parameter) space.
The talk is illustrated with a number of examples. We also discuss
briefly the numerical analysis (accuracy) of the method and the
consideration of multiple quantities of interest and data
assimilation.
","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/04urqj5di2e88vcd9tq04uoa58","2010-08-05 09:45:39","2010-11-04 15:23:43"
"717","6","A unified approach for some CFD problems with free  boundaries/moving interfaces, and irregular domains","2010-11-16 15:00:00",NULL,"SAS 4201","Zhilin Li","http://www4.ncsu.edu/~zhilin/","NC State","NA Seminar",,"The Immersed Interface Method (IIM) is an efficient numerical method for interface, free boundary/moving interface problems, and problems on irregular domains. The IIM is a sharp interface method that enforces jump conditions either exactly or approximately. In this talk, I will summarize some recent advances of the IIM, particularly, the augmented approach and its application to incompressible Stokes and Navier Stokes
equations with singular sources, discontinuous viscosity, irregular domains, and free boundary and moving interfaces using the augmented IIM. Particularly, I will explain the approach for incompressible (or inextensible) interfaces) in incompressible flows. Most previous work has been done using Stokes equations model by the boundary integral method. The problem is essentially an inverse problem to find an unknown surface tension such that the incompressible condition is satisfied. Geometrically, both the area and length of the interface has to be preserved. In our work, the method can be applied to both the Stokes or Navier-Stokes equations. We propose a new way to enforce the pressure jump conditions. Some new numerical simulation results will also be presented.

Using the augmented IIM, an open problem is how to develop preconditioning techniques for the Shur compliment for which we only know the matrix-vector multiplication. I show one example whose condition number is order one, but almost all the Matlab iterative solvers failed.

If time allows, I will also present the sensitivity analysis for flow past different objects with respect to the Reynolds number and its effect on the lift/drag coefficients if time permits. This is a joint work with Dr. Ito.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/51ln84o0bt5jn5k633kb4sslvs","2010-08-05 09:48:45","2010-11-05 10:15:27"
"718","6","A fast quadrature-based numerical method for the continuous spectrum biphasic poroviscoelastic model of articular cartilage","2011-01-25 15:00:00",NULL,"SAS 4201","Mansoor Haider","http://www4.ncsu.edu/~mahaider/","NC State","NA Seminar",,"Viscoelasticity of many biological soft tissues is modeled using a hereditary stress-strain law in which the relaxation function has a continuous spectrum of characteristic relaxation times.   When coupled with the governing (momentum) equation, numerical solution can be costly due to the dependence of the solution at the current time on the entire strain history.  In this talk, a new and efficient method for numerical solution of the continuous spectrum biphasic poroviscoelastic (BPVE) model of articular cartilage is presented.   Development of the method is based on a composite Gauss-Legendre quadrature approximation of the continuous spectrum relaxation function that leads to an exponential series representation. The separability property of the exponential terms in the series is exploited to develop a numerical scheme that can be reduced to an update rule requiring retention of the stain history at only the previous time step.  The cost of the resulting temporal discretization scheme is O(N) for N time steps. Application and calibration of the method is illustrated in the context of a finite difference solution of the one-dimensional confined compression BPVE stress-relaxation problem.  Accuracy of the numerical method is demonstrated by comparison to a theoretical Laplace transform solution for a range of viscoelastic relaxation times that are representative of articular cartilage.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gglv5ue70qsbn5ajjpc3evav58","2010-08-05 09:52:45","2010-10-17 10:20:19"
"719","6","Rank-deficient and ill-conditioned nonlinear least squares problems","2010-09-21 15:00:00",NULL,"SAS 4201","Tim Kelley","http://www4.ncsu.edu/~ctk/","NC State","NA Seminar",,"We tell our students that the way to solve an ill-condidtioned or rank-deficient linear least squares problem is to truncate the singular value decomposition and solve the problem with the new matrix which, one hopes, is better conditioned. When you apply that idea for nonlinear least squares problems, classical theory shows that all is well. The classical theory does not account for perturbations, and a new theory that does is much less optimistic. We show via a simple example that the problems with the classical theory happen in practice. Subset selection is an alternative way to regularize these problems that performs much better. 

This is joint work with Ilse Ipsen and Scott Pope.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9g4r8okoghinrkq3qe6oa2j2jo","2010-08-05 10:01:33","2010-08-05 11:29:57"
"720","6","Compact high order schemes for the Helmholtz equation with variable coefficients","2010-09-28 15:00:00",NULL,"SAS 4201","Semyon Tsynkov"," http://www4.ncsu.edu/~stsynkov/","NC State","NA Seminar",,"In many problems, one wishes to simulate the propagation of waves in inhomogeneous media, and use a high order accurate method (e.g., fourth order accurate) to alleviate the points-per-wavelength constraint. At the same time, one often prefers to have a scheme built on a compact stencil, as it considerably simplifies setting the boundary conditions and also helps reduce the bandwidth of the resulting matrix. Time-harmonic waves in an inhomogeneous medium are governed by the Helmholtz equation with variable coefficients within the Laplacian-like term. This renders existing fourth order finite difference methods inapplicable. We develop a new compact scheme that is provably fourth order accurate even for these formulations. Our numerical results corroborate the design properties of the scheme.

Work supported by AFOSR, NSF, and US-Israel BSF. Joint with S. Britt (NCSU) and E. Turkel and M. Medvinsky (Tel Aviv). ","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qbuj0mnomf4fd1rp6p1gavmv8k","2010-08-05 11:28:19","2010-08-05 12:38:50"
"721","6","A general, moment-based, scale-bridging algorithm including Newton-Krylov methods","2010-10-26 15:00:00",NULL,"SAS 4201","Dana Knoll",,"Los Alamos National Laboratory","Tim Kelley",,"We are developing a consistent, scale-bridging algorithm which accelerates an accurate solution of the fine scale equations to the point where coarse time and length scales are achievable.  Our prototype fine scale problem has time, configuration space, and phase space as independent variables.  This fine scale model is often referred to as the ""kinetic"" problem, and the discretized version of this problem will be referred to as the High Order (HO) problem.  The kinetic problem could be solved by either a deterministic or Monte-Carlo approach.  We will accelerate the solution to this fine problem using a Low Order (LO) problem as a coarse space preconditioner.  The LO problem is derived from a small number of phase space moments of the HO problem, and can also be solved on a coarser configuration space mesh.  We self-consistently determine the higher-order moments required by the LO problem with the local (in time and space) phase-space solution of the HO problem.  The potential impact for these algorithmic advancement is best summarized by selected list of applications. These could include: neutron transport; photon transport; plasma kinetic simulation; rarefied gas dynamics; transport in condensed matter e.g., semiconductors to name a few.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dvlrgl6v3lp63d24d0a3h6je58","2010-08-07 19:04:18","2010-10-20 10:26:00"
"722","4","Exact solutions for water wave Bragg resonances by periodic bottom corrugations of finite amplitude","2010-10-20 15:00:00",NULL,"SAS 4201","Jie Yu","http://www4.ncsu.edu/~jyu4","Department of Civil, Construction, and Environmental Engineering, NC State","Stephen Schecter",,"Strong and constructive scattering occurs when water waves propagate over bottom corrugations whose wavelength is close to an integer multiple of half a water wavelength. This is the phenomenon of Bragg resonance of water waves by periodic alongshore sandbars. Previous studies have mostly focussed on small amplitude corrugations, and on the primary (m=1) resonance.  Exact solutions have recently been developed for finite amplitude corrugations using a Floquet theory of linearized water waves, which also allows studies of higher order (m>1) resonances. Using the exact theory, we examine the ranges of water wave frequencies (resonance tongues) within which the wave amplitude exhibits slow exponential modulation in space, and outside which slow sinusoidal modulation occurs. The effects of Bragg resonances are illustrated using the normal modes of a rectangular tank.  Application to the scattering problem by a finite patch of corrugations in an otherwise flat bed will be discussed.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/veosnufql44pihd4ceqj4ge6kc","2010-08-16 11:04:00","2010-09-16 14:14:58"
"723","8","Zeilberger's algorithm","2010-10-13 16:00:00",NULL,"SAS 4201","Moa Apagodu",,"Virginia Commonwealth University",,,"We will discuss extension of Zeilberger algorithm from one-variable to multi-variables and the sharpening of the upper bounds for the order of the recurrence relation outputted by the algorithm. We will also discuss a systematic search for those $2F1$ functions evaluable in closed-form.
There are a number of conjectures associated with the last part of the talk.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oip10t7h8a6i3o1f6d6c550m6g","2010-08-17 12:58:24","2010-10-10 21:05:24"
"724","8","Counting positive roots of polynomials with applications for biochemical systems","2010-09-15 16:00:00",NULL,"SAS 4201","Anne Shiu",,"Duke University",,,"A complete root classification of a parametrized real univariate
polynomial describes the number of real roots of the polynomial as a
function of its coefficients.  For instance, the number of real roots
of a quadratic polynomial depends only on the sign of its
discriminant.  This talk focuses on an application of root
classification for the analysis of biochemical systems.  One class of
such systems are the multisite phosphorylation systems, which play an
important role in transmitting information in biology.  We extend work
of Wang and Sontag (2008) on the capacity of these systems to exhibit
multiple steady states.  We also highlight recent results on understanding
when the steady state locus of a biochemical system is cut out by binomials.
This is joint work with Alicia Dickenstein and Mercedes Pérez Millán.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g00n3p8tj8d2ir89hni56dnlio","2010-08-18 08:27:52","2010-08-30 10:20:48"
"725","8","Defining Equations of Secant Varieties to Segre-Veronese Varieties","2010-10-20 16:00:00",NULL,"SAS 4201","Luke Oeding",,"Università degli Studi di Firenze",,,"In work with Daniel Erman and Dustin Cartwright, we describe the de&#64257;ning ideal of the rth secant variety of P^2 xP^n embedded by O(1,2), for arbitrary n and r <= 5. We also present the Schur module decomposition of the space of generators of each such ideal. Our main results are based a more general construction for producing explicit matrix equations that vanish on secant varieties of products of projective spaces. This extends previous work of Strassen and Ottaviani. Our matrix equations are simple to understand, and I will present them at the level of basic linear algebra. Then I will show the invariant presentation of the equations. I will explain why these equations are always necessary defining equations of secant varieties. I will describe our results which say when these equations are also sufficient to define the ideal.  In addition, I will give several examples to illustrate the limits of these equations.  Finally, I will mention applications of these results to signal processing.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c35t1jj6dce386d261k4tdeqbs","2010-08-18 08:36:14","2010-10-18 10:40:25"
"726","27","Foundations of Computational Mathematics (FoCM'11)","2011-07-04 00:00:00","2011-07-14 00:00:00","Budapest",,,,"Szanto","http://www.damtp.cam.ac.uk/user/na/FoCM11",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dn8oqv3n8rg9ig88kn07h8ia20","2010-08-18 09:00:06","2010-08-18 09:00:21"
"727","4","Localized strongly nonlinear magnetic nano-waves","2010-10-27 15:00:00",NULL,"SAS 4201","Mark Hoefer","http://www4.ncsu.edu/~mahoefer","NC State",,,"Magnetic materials yield a rich variety of intriguing nonlinear wave phenomena.  Recent theoretical and experimental developments have enabled the controlled manipulation of magnetic moments on the nanometer length scale, the magnetic exchange length, enabling new physical insight into nonlinear dynamics and holding great promise for technological applications.  Dynamic, strongly nonlinear, localized wave structures varying on the exchange length scale have been studied theoretically since the late 70s but have not yet been observed.  In this talk, it is proposed that one member of this family of solitary waves for the Landau-Lifshitz equation, the two-dimensional nontopological droplet, could be experimentally realized in a spin torque nanocontact system that delivers a localized torque to an anisotropic ferromagnetic thin film, balancing the inherent material damping.  The dissipative droplet exhibits several interesting properties including strong nonlinearity, hysteretic behavior, and a drift instability leading to droplet propagation.  The governing Landau-Lifshitz equation does not possess a Galilean invariance, so propagating localized structures are nontrivial generalizations of stationary ones.  Using asymptotic and numerical methods, a family of propagating localized solitary wave solutions to the Landau-Lifshitz equation with easy-axis anisotropy will be constructed and their properties elucidated.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ee1kjjmgd5bburqot2vlm481p0","2010-08-18 10:33:26","2010-09-15 11:26:32"
"728","14","Fall Departmental Meeting","2010-08-26 16:00:00",NULL,"SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3ta6n69p2imib6900bhnrrepi0","2010-08-19 12:10:54","2010-08-19 14:30:26"
"729","14","Departmental Meeting Refreshments","2010-08-26 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6ne3lb1hg61m5hf1baa8n4jvm4","2010-08-19 12:12:51","2010-08-19 14:30:12"
"730","4","Structure-preserving nonholonomic integrators","2010-08-25 15:00:00",NULL,"SAS 4201","Dmitry Zenkov","http://www4.ncsu.edu/~dvzenkov","NC State",,,"When simulating mechanical systems numerically, it may be desirable to preserve various intrinsic structures. For instance, in the absence of velocity constraints, it is desirable to preserve a symplectic form. Many of these structures fail to be invariant in systems with velocity constraints. Integrators that preserve suitable quantities in the presence of velocity constraints will be introduced.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2jkvvpic75rk8ej6d7plh1nvps","2010-08-20 16:18:37","2010-08-23 11:46:25"
"731","4","Stability of traveling waves for a class of reaction-diffusion  systems that arise in chemical reaction models","2010-09-08 15:00:00",NULL,"SAS 4201","Steve Schecter","http://www4.ncsu.edu/~schecter","NC State",,,"I’ll discuss rigorous nonlinear stability results for traveling waves in a class of reaction-diffusion systems that arise in chemical reaction models. The class includes systems in which there is no diffusion in some equations.  The results are detailed enough to show, for example, that the results of adding some heat or adding some reactant to a combustion front are different.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mnvlm5107tjitgmv4qhis2l4q4","2010-08-20 16:22:43","2010-08-26 11:06:29"
"732","24","Math Mixer","2010-08-25 17:00:00",NULL,"SAS 4104",,,,,,"MGSA will be hosting it's annual ""Math Mixer"" this Wednesday, August 25th. It will be held from 5-7 pm in the SAS fourth floor lounge. Pizza, subs and refreshments will be provided. Everyone in the math department is welcome!!
 
MGSA will be selling cheap (in price, not in quality) department water bottles and mugs, so if you would like to purchase any bring some cash/check with you.  ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3gdppnvkciitrusouvb3uviv5o","2010-08-22 21:30:25",NULL
"733","23","Fundamentals of Latex","2010-08-27 15:00:00",NULL,"SAS 4201","Zhengzheng Hu","http://www4.ncsu.edu/~zhu4/Zhengzheng/Welcome.html","NC State Postdoc","Ralph Smith",,"This will include discussion regarding the installation of Latex on your own machine as well as various typesetting commands and strategies including the incorporation of figures in documents. The presentation will thus include topics of interest for both beginning Latex folks and those interested in some of the more detailed points.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cf4c6nbfe093q5lp2qeqd170es","2010-08-24 11:17:33",NULL
"734","6","Numerical Strategies for Filtering Partially Observed Stiff Stochastic Differential Equations","2010-10-05 15:00:00",NULL,"SAS 4201","John Harlim","http://www4.ncsu.edu/~jharlim/","NC State","NA Seminar",,"In this presentation, I will describe a fast numerical strategy for filtering stochastic differential equations with multiscale features. This method is designed such that it does not violate the practical linear observability condition and, more importantly, it does not require the expensive cross correlation statistics between multiscale variables that are typically needed in standard filtering approach. The proposed filtering algorithm comprises of a ``macro-filter"" that borrows ideas from the Heterogeneous Multiscale Methods and a ``micro-filter"" that reinitializes the fast microscopic variables to statistically reflect the unbiased slow macroscopic estimate obtained from the macro-filter and observations of the macroscopic variables at asynchronous times. The proposed micro-filter is essentially equivalent to solving an inverse problem for parameterizing differential equations. Numerically, I will show that this microscopic reinitialization is an important novel feature for accurate filtered solutions, especially when the microscopic dynamics is not mixing at all.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8t91kp4klhvqenkaojbgp3l5a0","2010-08-24 14:50:04","2010-09-23 09:08:43"
"735","3","Linear Systems on Tropical Curves","2010-10-29 16:00:00",NULL,"SAS 4201","Josephine Yu",,"Georgia Tech",,,"A tropical curve is a metric graph with possibly unbounded edges, and tropical rational functions are continuous piecewise linear functions with integer slopes. We define the complete linear system |D| of a divisor D on a tropical curve analogously to the classical counterpart. We investigate the structure of |D| as a cell complex and show that linear systems are tropical modules, finitely generated by vertices of the cell complex. Using a finite set of generators, |D| defines a map from the tropical curve to a tropical projective space, and the image can be extended to a parameterized tropical curve of degree equal to deg(D). The tropical convex  hull of the image realizes the linear system |D| as an embedded polyhedral complex.  We also show that curves for which the canonical divisor is not very ample are hyperelliptic.  This is joint work with Christian Haase and Gregg Musiker.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nctj2u22odihl930c5j2bva8i4","2010-08-25 15:42:48","2010-08-27 09:40:08"
"736","6","Linear Algebra and Large Informatics Graphs","2010-09-03 13:30:00",NULL,"SAS 4201","Michael Mahoney","http://cs.stanford.edu/people/mmahoney/","Stanford University",,,"Linear algebra has long had applications in scientific computation and data analysis, two areas that make very different demands on their matrices.  In recent years, there have been several high-profile examples of applications of linear algebra to data analysis problems.  For example, latent semantic analysis of term-document data, ranking web pages with PageRank, and normalized cut spectral partitioning for image segmentation. While these methods use linear algebra in ways that are fairly familiar to linear algebra researchers, most machine learners and data analysts who use linear algebra do so in very different ways, some of which suggest interesting new directions for the area.  To illustrate possible future directions, I'll review an extreme (but extremely important) example where traditional linear algebra methods (as well as, in fairness, many other methods from machine learning and data analysis) failed rather egregiously.  The application has to do with analyzing empirically the large-scale structure of large informatics graphs such as large social and information networks, a problem clearly of considerable interest in its own right.  I'll review the results of our large-scale empirical analysis (by far, the most comprehensive to date) that uncovered surprisingly subtle and counterintuitive properties that existing models fail to reproduce even qualitatively.  Then, I'll describe two examples of ""new linear algebra"" that arose during this investigation.","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ho4pdrlm1eq6p09rj1bfkcrang","2010-08-25 17:20:29","2010-08-26 13:37:43"
"737","3","Why there are only 17 Wallpaper Groups (i.e. What I Learned during my REG)","2010-10-22 16:00:00",NULL,"SAS 4201","Amassa Fauntleroy","http://www4.ncsu.edu/~amassa/","NC State",,,"There is a beautiful and quite elementary proof, due to Schwarzenberger, of this classic result discovered in 1891 by Fedorov and later in 1924 independently by Polya. The proof uses basic trigonometry and is accessible to undergraduates. It is also a classic example of how the word “obvious” can obfuscate the obvious. I will discuss this proof and it’s relationship to the modern (this decade) proof by Thurston, Conway et al of the classification of the 230 crystallographic groups. I am indebted to my REG student for leading me to this beautiful mathematics.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2vb5muj1v59m9s4qcjth81n4oc","2010-08-26 14:16:47","2010-10-18 14:39:25"
"738","27","Triangle Lectures in Combinatorics","2010-09-25 08:00:00",NULL,"Duke University",,,,,"http://www.math.ncsu.edu/TLC/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v60up1gm00glis841p3uo6drbg","2010-08-26 14:53:45",NULL
"739","26","Synthesis of Second Generation Biofuels","2010-08-30 16:00:00",NULL,"SAS 4201","Lucus Van Blaircum",,"NC State Mathematics Graduate Student",,,,"krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pjdejnv747j94c0t9bos34qpa0","2010-08-26 16:25:00",NULL
"740","3","Operads and renormalization","2010-09-17 16:00:00",NULL,"SAS 4201","Nikolay M. Nikolov",,"INRNE, Bulgarian Academy of Sciences",,,"I will present  a combinatorial construction of the renormalization group related to a certain operad. The renormalization group is the group of all possible finite changes of the renormalization in a given renormalizable quantum field theory. I will introduce the notion of ""quantum field theory"" only at the combinatorial level, which is a class of certain colored graphs (Feynman diagrams).  Then I will introduce the renormaliztion group as a group related to a certain operad, which I call the renormalization operad. An operad is a notion similar to the notion of a category in mathematics and describes ""types of algebras"".","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/refuu215i71iv95qe4a7m7424k","2010-08-27 13:12:15","2010-09-16 16:49:07"
"741","4","Sessile drop oscillations: contact line dynamics and symmetry breaking","2010-09-15 15:00:00",NULL,"SAS 4201","Joshua Bostwick",,"Department of Theoretical and Applied Mechanics, Cornell University","Michael Shearer",,"Oscillations of a sessile drop are of interest in a number of industrial applications, such as ink-jet printing and drop atomization, among others. We consider the small oscillations of the inviscid sessile drop under a number of contact line conditions, including a moving contact line modeled by a continuous contact-angle against speed relationship.  The integro-differential equation, governing the motion of the interface, is formulated as a functional equation using inverse operators, which are parameterized by azimuthal wave-number and volume via the static contact angle of the drop base-state.  In the symmetric limit, a hemispherical drop given a fixed contact angle disturbance has characteristic oscillation frequencies, which are degenerate with respect to azimuthal wave-number much like the Bohr model of the atom is degenerate with respect to angular momentum quantum number. This degeneracy can be attributed to the configurational symmetry of the hemispherical base-state and is broken by smoothly varying either i) the volume or ii) the contact line condition. An analogy is made between the spectrum of these `broken’ states and the filling order of the periodic table by energy levels. ","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b7ifko405snh8pub3vf8k2o9g0","2010-08-28 15:07:55","2010-09-10 09:43:40"
"742","14","Departmental Tea and Cookies","2010-09-01 15:00:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/uf2qvaqpd1a1t0r813ghhdl9l0","2010-08-30 14:28:57",NULL
"743","3","Universal (poly)matroid valuations","2010-10-01 16:00:00",NULL,"SAS 4201","Alex Fink",,"NC State",,,"Many important invariants for matroids, among them the Tutte polynomial and several recent examples, are _valuative_, i.e. they essentially behave additively on matroid polytope subdivisions. We give natural combinatorial bases for the group of matroid valuations, and of several variants, including generalisations to polymatroids and to invariant functions. The structure of these groups is further illuminated by recognising them as Hopf algebras. These results confirm Derksen's conjecture of a universal property for his valuative invariant.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h512a42hvp0v4sqjnv532fecjc","2010-08-30 15:24:28","2010-09-27 07:56:23"
"744","22","Financial Mathematics: How mathematicians develop pricing models","2010-09-01 16:00:00",NULL,"SAS 2102","Jeff Scroggs",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/090110.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/710hbr3v18cv27agsa25j4trpc","2010-08-31 16:50:09",NULL
"745","22","What's a determinant, really?","2010-09-08 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/090810.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uig4f2qd7dqtnlc2ldgbum61dg","2010-08-31 16:51:21",NULL
"746","22","The Abacus of Calculus","2010-09-15 16:00:00",NULL,"SAS 2102","Molly Fenn",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/091510.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o31m91e5sgjlg1rigrsc2n4jp0","2010-08-31 16:52:03","2010-09-13 11:10:31"
"747","22","The Combinatorics of Card Shuffling","2010-09-22 16:00:00",NULL,"SAS 2102","Sami Assaf","http://www-math.mit.edu/~sassaf/","MIT",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/092210.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c2r0lthkrhn8g32gfp078is4t8","2010-08-31 16:54:12",NULL
"748","22","Wavelet analysis of circadian rhythms and jet lag","2010-09-29 16:00:00",NULL,"SAS 2102","Tanya Leise","http://www.cs.amherst.edu/~tleise/","Amherst",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/092910.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/llp1okl1la0tqmtgp4cbgljagc","2010-09-01 08:39:31","2010-09-13 11:11:33"
"749","22","Applying matrix algebra to data clustering","2010-10-13 16:00:00",NULL,"SAS 2102","Chuck Wessell",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/101310.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8e60hiiscra1948ritrekceqm4","2010-09-01 08:41:06","2010-10-12 08:44:11"
"750","22","Computational Combinatorics and Graph Ramsey Theory","2010-10-20 16:00:00",NULL,"SAS 2102","Michael Schuster",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/102010.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v9u4cb19urteico7h8f3u1f008","2010-09-01 08:41:53","2010-10-15 13:50:47"
"751","22","Linear Algebra to the Rescue: Radio Tomographic Imaging","2010-10-27 16:00:00",NULL,"SAS 2102","Anjela Govan",,"Northrop Grumman",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/102710.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/abtl02k6dbu31tnr5tjo3o2hkk","2010-09-01 08:46:18","2010-09-13 11:13:11"
"753","22","Undergraduate research presentations","2010-12-01 16:00:00",NULL,"SAS 2102","TBA",,"NC State",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u8j3hd3k629gg6i0mn729bmbmk","2010-09-01 08:48:03",NULL
"754","23","Fundamentals of Webdesign Using Dreamweaver","2010-09-10 15:00:00",NULL,"SAS 4201","Seyma Bennett-Shabbir",,"NC State","Ralph Smith",,"Effective webpages are an increasingly important medium for disseminating information related to classes and research.  For TA's, they provide a critical way to share material with your class whereas for those entering the job market, they are often checked by potential employers interested in obtaining more information about candidates.  Hence it is important to construct and maintain your webpage in a manner that is both easy and professional.

In this session, Seyma will discuss the use of Dreamweaver, which is one of the most widely used software packages for webpage design.  Dreamweaver is available on machines in the Multimedia Center and across campus.  Seyma will bring the labtop cart so you will get hands on experience.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ecc3eetdleksf49s54avr4vgk0","2010-09-07 12:24:40",NULL
"755","14","Departmental Tea and Cookies","2010-09-09 15:00:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fdhua3ulpav3s0q5m086d6hokc","2010-09-07 14:09:09",NULL
"756","26","Acoustic Excitation of Buried Targets","2010-09-13 16:00:00",NULL,"SAS 4201","Zack Kenz",,"NC State Mathematics Graduate Student",,,"Among methods for detecting buried targets, one possibility is attempting to excite the buried target through the introduction of acoustic waves into the soil and then detecting any induced target motion via electromagnetic interrogation. 
Here we report on only the first half of the problem, namely modeling the response in the soil to acoustic waves with and without a buried object. As a first approximation, we develop a one-dimensional model of an infinite column of dry soil which lies directly underneath the wave source. We utilize the equations of motion and assume a viscoelastic constitutive law in order to formulate the model. 
Computational results describing the soil motion inside the column are examined, and we also introduce a rigid body into the column and study the resulting acoustic wave form. This is work performed in collaboration with Dr. H.T. Banks, Dr. Shuhua Hu, and W. Clayton Thompson at NCSU; the team at L-3 Communications led by Dr. Jerrold Levine; and Dr. Richard Albanese.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/08gsfklfv9tv594rfs3u6i9sfg","2010-09-09 19:32:31",NULL
"757","26","Parameter estimation techniques for probabilistically distributed dynamics: computation and convergence","2010-09-13 16:30:00",NULL,"SAS 4201","Clay Thompson",,"NC State Mathematics Graduate Student",,,"In the mathematical modeling of physical and biological systems, it often happens that a system parameter is not constant but rather is distributed probabilistically within the population under study.  Inverse problems for such distributed dynamics models require the estimation of a probability measure over a set of admissible parameters.  This problem is well-known to both applied mathematicians and statisticians, and both schools have developed their own set of computational techniques and convergence results.  
Here, we present a comparison of these techniques with specific attention to theoretical (existence, uniqueness, convergence) and computational aspects of the methods as well as the strengths and weaknesses of the methods under various conditions.  In particular, we focus on the discrete approximation methods of Banks-Bihari and Banks-Fitzpatrick and the non-parametric MLE methods of Davidian, Gallant, and Nychka.  Joint work with Zackary R. Kenz and H.T. Banks.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sknm4nl8fhpd3kgbh5lhhcj3lo","2010-09-09 19:35:05",NULL
"758","14","Dr. Charlton's Retirement Party","2010-10-05 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/q8p893afee8d9i4lo24ihj7ne8","2010-09-10 11:16:52",NULL
"759","14","Departmental Tea and Cookies","2010-09-15 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/15ocjalr9hqp8siuiif8l4b1t0","2010-09-13 14:32:47",NULL
"760","3","Feynman periods and higher order calculations in perturbative quantum field theory","2010-10-15 16:00:00",NULL,"SAS 4201","Nikolay M. Nikolov",,"INRNE, Bulgarian Academy of Sciences",,,"Perturbative quantum field theory is the main tool for making predictions in high energy physics. The calculations are based on evaluating Feynman integrals. This has led to new insights on problems in algebraic geometry and number theory (cf., e.g., works of S. Bloch and D. Kreimer). A (renormalized) Feynman integral determines a complex number, its residue, which in general is a period. In this talk I will show how by using cohomologies of configuration spaces one can express the Feynman periods by multiple zeta values. A configuration space over a topological space X is the space of all configurations of distinct points of X. This simple construction has many deep applications in mathematics.
 
References:
1. N.M. Nikolov, ""Cohomologies of Configuration Spaces and Higher-Dimensional Polylogarithms in Renormalization Group Problems"", AIP Conf. Proc. 1243, 165 (2010) (dx.doi.org/10.1063/1.3460163)
2. N.M. Nikolov, ""Talk on Anomalies in Quantum Field Theory and Cohomologies of Configuration Spaces"", arXiv:0907.3735","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m3lndmjs4liq5vijo0hl3ij7mg","2010-09-13 15:00:59","2010-10-12 15:11:21"
"761","3","On randomizing two derandomized greedy algorithms","2010-09-24 16:00:00",NULL,"SAS 4201","Kevin Costello",,"Georgia Tech",,,"Many of the simplest and easiest implemented approximation algorithms can be thought of as derandomizations of the naive random algorithm. Here we consider the question of whether performing the algorithm on a random reordering of the variables provides an improvement in the worst case expected performance. (1) For Johnson's algorithm for Maximum Satisfiability, we show this is indeed the case: While in the worst case Johnson's algorithm only provides a 2/3 approximation, the additional randomization step guarantees a 2/3+c approximation for some positive c. (2) For the greedy algorithm for MAX-CUT, we show to the contrary that the randomized version does NOT provide a 1/2+c approximation for any c on general graphs. This is in contrast to a result of Mathieu and Schudy showing it provides a 1-epsilon approximation on dense graphs. Joint with Asaf Shapira and Prasad Tetali.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/feou7id3itms7guhrtsq2mqed4","2010-09-13 15:08:08",NULL
"762","3","Classification and enumeration of special classes of posets and polytopes","2010-11-19 16:00:00",NULL,"SAS 4201","Hoda Bidkhori",,"NC State",,,"This talk concerns combinatorial and enumerative aspects of different classes of posets and polytopes. The first part concerns the finite Eulerian posets which are binomial, Sheffer or triangular. These important classes of posets are related to the theory of generating functions and to geometry. Ehrenborg and Readdy gave a complete classification of the factorial functions of infinite Eulerian binomial posets and infinite Eulerian Sheffer posets, where infinite posets are those posets which contain an infinite chain. We answer questions asked by R. Ehrenborg and M. Readdy. We completely determine the structure of Eulerian binomial posets and, as a conclusion, we are able to classify factorial functions of Eulerian binomial posets; We give an almost complete classification of factorial functions of Eulerian Sheffer posets by dividing the original question into several cases; In most cases above, we completely determine the structure of Eulerian Sheffer posets, a result stronger than just classifying factorial functions of these Eulerian Sheffer posets. This work is also motivated by the work of R. Stanley about recognizing the boolean lattice by looking at smaller intervals.

The second topic concerns lattice path matroid polytopes. The theory of matroid
polytopes  has gained prominence due to its applications in algebraic geometry,
combinatorial optimization,  Coxeter group theory, and, most recently, tropical
geometry. In general matroid polytopes are not well understood. Lattice path matroid polytopes  belong to  two famous classes of polytopes, sorted closed matroid polytopes and polypositroids. We  study several properties of  LPMPs and build a new connection between the theories of matroid polytopes and lattice paths. I investigate many properties of LPMPs, including their face structure, decomposition, and triangulations, as well as formulas for calculating their Ehrhart polynomial and volume.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7nsoobtsvr3docsg109nv8rhf0","2010-09-13 15:36:41",NULL
"763","21","A Place To Be You","2010-09-15 17:30:00","2010-09-15 19:00:00","BTEC 135",,,,,,"Google Technical talk and information session hosted by ACM/AITP.  CSC, ECE, Math, and Physics Majors welcome. Pizza and Swag provided.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/aqpguufn0ne95857eirsq8uoek","2010-09-15 12:59:09",NULL
"764","4","Stochastic closures and parametric estimation in multiscale systems","2010-09-22 15:00:00",NULL,"SAS 4201","Ilya Timofeyev","http://www.math.uh.edu/~ilya","University of Houston","John Harlim",,"In the first part of the talk we give an overview of the Stochastic Mode-Reduction strategy for deriving stochastic reduced models for a slow subset of dynamic variables. Application of this approach to a particular class of deterministic energy-conserving models will be discussed. In this approach asymptotic analysis and microcanonical averaging are utilized to derive closed-form reduced equations for long-term evolution of the slow subset.

In the second part of the talk we will discuss parametric estimation of reduced models from time-series of the essential dynamic variables alone. We discuss the question of sub-sampling of the data when it is desirable to approximate statistical features of a smooth trajectory by a stochastic differential equation. In this case estimation of the stochastic differential equation would yield incorrect results if the data set is too dense in time. Therefore, the data set has to be sub-sampled (i.e. rarefied) to ensure estimators' consistency.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/896flgft6bb2iuonbsord8coa8","2010-09-15 16:27:50","2010-09-16 14:13:55"
"765","26","The Buckley-Leverett Equation with Dynamic Capillary Pressure","2010-09-20 16:00:00",NULL,"SAS 4201","Kim Spayd",,"NC State Mathematics Graduate Student",,,"The  Buckley-Leverett equation for two phase flow in a porous medium is modified by including a dependence of capillary pressure on the rate of change of saturation. This model, due to Gray and Hassanizadeh, results in a nonlinear pseudo-parabolic partial differential equation. Phase plane analysis, including a separation function to measure the distance between invariant manifolds, is used to determine when the equation supports traveling waves corresponding to undercompressive shocks.  The Riemann problem for the underlying conservation law is solved and the structures of the various solutions are confirmed with numerical simulations of the partial differential equation.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dujhre75s30bi1bfioa1ddh8j0","2010-09-17 09:52:37",NULL
"766","26","Parameter Estimation for the Heat Equation on Perforated Domains","2010-09-20 16:30:00",NULL,"SAS 4201","Amanda Criner",,"NC State Mathematics Graduate Student",,,"We use the heat equation to simulate a thermal interrogation method for detecting damage in porous materials. We first use probability schemes to randomly generate pores in a sample
material; then we simulate flash-heating of the compartment along one of the boundaries with and without damage due to oxidation which is represented with a large ellipse. We will discuss the computational complexity from the complicated geometry of the porosity.  We then compare this computationally complex model to an alternative model which is derived using the results of homogenization theory.  The alternative model approximates the thermal effect of the porosity with a matrix A in the diffusivity term of the heat equation.  We then use this model to estimate thermal parameters from simulated data.  This work has been done in collaboration with H.T. Banks, D. Cioranescu and W.P. Winfree.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qnkdcfiplko1kif6a42jsllepc","2010-09-17 09:53:29","2010-09-17 19:10:58"
"767","21","2010 Todd Fuller Contest","2010-10-16 09:00:00","2010-10-16 11:00:00","SAS 2203",,,,,"http://www.math.ncsu.edu/undergrad/ncsu_contests/2010/index.php",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/29cpsj7c56s75horev3innl3p8","2010-09-17 10:35:00",NULL
"768","28","AWM Student Chapter Meeting","2010-09-23 14:30:00",NULL,"SAS 2102",,,,,,"AWM is The Association for Women in Mathematics. This is a club for both men and women and both graduate and undergraduate students. There will be an introductory meeting for AWM Student Chapter where we will discuss our plans for the year. Everyone is welcome and encouraged to join and there is no membership fee.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jegef04mvbecl9b9otg59eqv3c","2010-09-20 10:02:48",NULL
"769","20","Incorrect Convergence of  Computational  Solutions for a Burgers' Problem","2010-09-20 13:30:00",NULL,"Cox 306","David Gilliam",,"Texas Tech University",,,"A simple example for Burgers equation is  used to illustrate that even theoretically convergent numerical schemes can produce numerical steady state solutions that do not correspond to steady state solutions of the boundary value problem. This phenomenon should be considered in any computational study of non-unique solutions to partial differential equations that govern physical systems such as fluid flows.  The erroneous solutions arise from the use of  finite floating point arithmetic which is inherent in every digital computer.  We claim that the erroneous solutions are actually real solutions of a  ``nearby'' boundary value  problem containing  a nonzero parameter which is  considered zero in a finite floating point number system
on a computer.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kdrsvhp0rr14lged1toqtn77io","2010-09-20 15:20:01",NULL
"770","14","Departmental Tea and Cookies","2010-09-22 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/umu7a88l1sq4h4k3ugaadqensc","2010-09-20 15:22:12",NULL
"771","3","The charged free boson hierarchy","2010-12-03 16:00:00",NULL,"SAS 4201","Katie Liszewski",,"NC State Mathematics Graduate Student",,,"Classical integrable hierarchies, such as the KP and Toda hierarchies, have an algebraic construction, which relies on the boson-fermion correspondence, an isomorphism between the fermionic and bosonic Fock spaces. Analogously, the representation of gl_infinity formed by two charged free bosons can be identified with a bosonic Fock space via the Friedan-Martinec-Shenker bosonization. We construct the corresponding charged free boson integrable hierarchy and show that it has many of the properties of the classical hierarchies.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ocr41dv2l9q3ptupoe2mhj9rvs","2010-09-21 15:05:21","2010-11-29 09:03:44"
"772","23","Job Application Resources","2010-09-24 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"NC State","Ralph Smith",,"We are getting to that time in the year when students and postdocs may need to start thinking about the logistics of applying for jobs. In this week's RTM, a faculty panel will discuss job application resources for both academic and nonacademic positions.  This will include websites and publications advertising positions along with conferences such as the Joint AMS Meeting that link employers and applicants.  We will also discuss issues regarding the logistics associated with the application process.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j1burkjsj2mb56c5nu1nha3ndg","2010-09-22 11:06:20",NULL
"773","23","Research and Teaching Statements","2010-10-01 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"NC State","Ralph Smith",,"For students and postdocs applying for either academic or nonacademic positions, research statements are often required as part of the application package.  Additionally, teaching statements are typically required when applying for academic positions.  In this week's RTM, a faculty panel will discuss strategies for writing effective research and teaching statements.  Examples of both will be provided during the discussion.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fnv0f064cofj926n713uu8eb7s","2010-09-22 11:08:08",NULL
"774","6","A time-parallel multiscale algorithm for non-equilibrated  microscopic phenomena","2010-10-12 15:00:00",NULL,"SAS 4201","Sorin Mitran",,"UNC-CH","John Harlim",,"Many systems respond to time-varying macroscopic boundary conditions by changes in their microscopic structure. Establishing macroscopic constitutive laws for such systems is difficult, and analytical approaches typically require drastic simplifications of the microscopic behavior. This talk presents a multiscale numerical homogenization approach that combines consistent models of continuum, kinetic, and microscopic behavior. At the continuum level conservation laws are solved. The microscopic description is modeled by stochastic differential equations. Of special mathematical interest is the mesoscale, kinetic equation level. The computational difficulty of working in high-dimensional phase space is addressed by variational formulations of solutions to Fokker-Planck equations, which then provide a predictor algorithm for a time-parallelization approach to the microscopic dynamics. Applications to viscoelastic flow and cytoskeleton modeling are presented.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/77i22v1gm4t2s9jo8t0f3qo5s4","2010-09-23 09:09:53","2010-10-09 20:01:55"
"776","7","Renormalization and Central limit for small random perturbations of chaotic dynamical maps","2010-10-11 14:00:00",NULL,"SAS 4201","Oliver Diaz","http://www.math.duke.edu/~odiaz/","Mathematics, Duke University","Min Kang",,"We study the effects of small random perturbations on one dimensional maps that admit a renormalization group theory: unimodal maps, critical circle maps for example. We show that several statistics of the propagated  noise satisfies some scaling relations. In particular, we show that the effective accumulated noise has a Central Limit Theorem.
","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n1pv9m2pasmcr5uvksl99bk8bg","2010-09-24 17:44:02","2010-10-01 13:51:08"
"777","1","Sorting and merging via stochastic differential equations: new models for some problems in statistical mechanics","2011-03-17 16:00:00",NULL,"SAS 1102","Roger Brockett","http://people.seas.harvard.edu/~brockett/brockett.html","School of Engineering and Applied Sciences, Harvard University","Dmitry Zenkov",,"Recent publications in the condensed matter physics literature consider randomized algorithms for sorting a list of numbers as possible models for experimental results showing a type of ""memory"" associated with nonequilibrium processes such as the cooling of glass.  On the other hand, it was observed more than twenty years ago that there are certain dynamical systems, e.g. the Toda lattice, that can be viewed as continuous versions of bubble sort, an elementary  sorting algorithm often taught in beginning  computer science classes.  Although less well known, there are stochastic versions of these continuous sorting algorithms, naturally defined by a certain Lie algebraic structure in concert with the Ito calculus.  In some cases these differential equation versions have explicitly computable invariant measures; this is best appreciated by realizing that the Toda lattice can be considered to be a gradient flow, distinct from its more widely appreciated Hamiltonian structure.  In this talk we will attempt to weave together these threads and relate them, at least in a loose way, to the experimental observations mentioned above.  At the same time, we will discuss how Lie theory suggests a wider class of dynamical systems, apparently not directly related to Hamiltonian mechanics, but still having the potential to describe the phenomena in question.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/ns0d7iqkd9h8l4lu42d2h1fp4k","2010-09-25 12:22:11","2011-01-26 11:06:30"
"779","14","Departmental Tea and Cookies","2010-09-29 15:00:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bsai0657nk4udr0sh4nudog62o","2010-09-27 14:52:55","2010-09-27 14:53:53"
"780","1","Modeling diversity in tumor populations","2011-02-17 16:00:00",NULL,"SAS 1102","Rick Durrett","https://fds.duke.edu/db/aas/math/faculty/rtd","Duke University","Min Kang",,"Heterogeneity of cancer cell populations makes treatment difficult because most drugs target one particular mutational change. In this talk I will discuss a branching process model in which mutations make random changes in the birth rates, in order to study the variation among the cells within a single tumor. We have results for the asymptotic growth rates of the population as well as for two commonly used measures of diversity. We get surprisingly explicit conclusion thanks to old results for one-sided stable laws.

This is joint work with J. Foo, K. Leder and F. Michor at the Dana-Farber Cancer Institute, and former Cornell postdoc J. Mayberry, now at University of the Pacific.

(Joint Colloquium with Department of Statistics)","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/dp4npuec7407k6nbgouhilql8k","2010-09-29 15:59:06","2011-02-02 10:18:02"
"781","26","Computational Strategies for Spatio-Temporal Filtering in Multiscale Systems","2010-10-04 16:00:00",NULL,"SAS 4201","Emily Kang",,"NC State Mathematics Postdoc",,,"Dynamical systems with multiple spatio-temporal scales are common in applied sciences and engineering, such as weather and climate dynamics. In this talk, we investigate fast computational strategies for filtering partially observed systems with multiscale features.  We develop filtering algorithms which combine the Heterogeneous Multiscale Methods (HMM) with filtering approaches, such that they do not require the cross covariances between multiscale variables which are typically needed in standard filtering approaches but not computationally feasible in multiscale systems. The proposed filtering algorithms are tested in the framework of the 2-layer Lorenz 96 model. (Joint work with John Harlim)","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/41vj093e74ntq567j6haes4tb4","2010-09-30 12:41:42",NULL
"782","7","Optimal Stopping of Markov Chains, Gittins Index and Related Optimization Problems","2010-10-28 14:00:00",NULL,"SAS 4201","Isaac Sonin","http://www.math.uncc.edu/~imsonin/","University of North Carolina at Charlotte","Min Kang",,"The celebrated Gittins index, its generalizations and related techniques play an important role in applied probability models, resource allocation problems, optimal portfolio management problems as well as other problems of financial mathematics.
	
 It is well known that 1) a connection exists between the Ratio (cycle) maximization problem, the Kathehakis-Veinot (KV) Restart Problem and the Whittle family of Retirement Problems, and 2) that their key characteristics, the classical Gittins index, the KV index, and the Whittle index are equal. These indices were generalized by the author (Statistics and Probability Letters, 2008) in such a way that it is possible to use the so called State Elimination algorithm, developed earlier to solve the problem of Optimal Stopping of Markov Chains to calculate this common index alpha.
	
In this talk I will discuss the problem of Optimal Stopping of Markov Chains, the State Elimination algorithm, the classical and the generalized Gittins indices and related problems. One of the main goal of this talk is to demonstrate that the equality of these indices is a special case of a similar equality for three simple abstract optimization problems. By an abstract optimization problem we mean a problem with maximization over an abstract set of indices U without any specifics about this set.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q2h3bosepb7tq2djjdpl6kpt4k","2010-10-01 12:11:50","2010-10-19 17:57:41"
"783","7","Ergodic theorems for the branching – diffusion processes in the homogeneous or random environment","2010-11-08 14:00:00",NULL,"SAS 4201","Stanislav Molchanov","http://math.uncc.edu/index.php/people/full-time-faculty/294-molchanov-stanislav-.html","University of North Carolina at Charlotte","Min Kang",,"We will discuss the existence and qualitative properties of the stationary in space and time particle systems with the birth, death and stochastic spatial dynamics. In the 2D homogeneous case, such system exists only if the underlying random walk includes the long jumps. We also will consider similar models in the random environment. If it is time independent (the stationary one), then typically the ergodic regime is not possible. However, in the non-stationary environment the ergodicity has place under appropriate technical restrictions.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ub09e93jhio12pa8s8r6grubbs","2010-10-01 12:16:13","2010-10-18 13:05:32"
"784","1","Cell Measurement Theory","2010-10-12 16:00:00",NULL,"SAS 1102","James Keener","http://www.math.utah.edu/~keener","University of Utah","Steve Schecter",,"All living organisms must make measurements and then make behavioral decisions in response.  For example, cells must decide when to divide, when to differentiate, when to grow, when and where to move, when to repair, and when to die.  A fundamental question is how cells make these measurements and the ensuing decisions.  Some underlying principles are coming to light.  The short answer is that the rate of molecular diffusion contains quantifiable information that can be transduced by biochemical feedback to give control over physical structures.  In this talk, I use mathematical modeling and analysis to illustrate how rates of molecular diffusion are used to make measurements and behavioral decisions. ","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/3n2ela29c30nggvg3ndt05j0a4","2010-10-02 10:16:50","2010-10-04 09:54:26"
"785","4","Traveling waves for a model of a fungal disease in a vineyard","2010-10-13 15:00:00",NULL,"SAS 4201","Shangbing Ai","http://ultra.math.uah.edu/~ai","University of Alabama in Huntsville","Xiao-Biao Lin",,"Powdery mildew is a major type of fungal disease spreading in vineyards. It is caused by the fungus Uncinula necator and spread by spores (produced by colonies of the fungus) located on the vegetal tissue of grapevines. Mathematical models have been developed to understand spatio-temporal spreading of the disease. In this talk, we discuss a particular model and its traveling wave solutions, obtained by geometric singular perturbation theory and center manifold theory. ","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h65stivhh7niqvtkja3o4m1qf8","2010-10-02 10:23:32","2010-10-02 10:24:12"
"786","14","Departmental Tea and Cookies","2010-10-12 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0f44hb44pd5g1cp23n1jqktups","2010-10-04 10:27:59",NULL
"787","26","Modeling Time Dependent Electroosmotic Flow","2010-10-11 16:00:00",NULL,"SAS 4201","Emi Lipcsey-Magyar",,"NC State Mathematics Graduate Student",,,"Capillary Electrophoresis (CE) is a new analytical chemistry technique that is faster, requires less sample, and generates less chemical waste than conventional methods. CE separations have a higher separation resolution than current technology and would therefore improve pathogen screenings and other blood tests. One of the major downfalls of CE is the presence of irreproducible Electroosmotic Flow (EOF). EOF is the velocity of liquid through a glass capillary when an external potential is applied. In order to predict trends in EOF, a mathematical model is needed. A biexponential function, the sum of two exponential terms, is predicted to best model EOF during discontinuous buffer conditions. Several data sets were collected and analyzed to verify this prediction.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nn15nl8mq7pl2gbuvh4iocr1kc","2010-10-05 13:19:58",NULL
"788","23","Optimizing your Conference Experience","2010-10-15 15:00:00",NULL,"SAS 4201","Department Faculty and Grad Students",,"North Carolina State University","Ralph Smith",,"Conferences provide an invaluable experience for graduate students and postdocs for a number of reasons: they provide a forum to learn and talk about new mathematics and science, network and meet new people, and possibly meet potential employers.  To optimize the benefit from attending a conference, one needs to plan ahead and be aware of certain strategies.  In this RTM, a panel of faculty and graduate students will discuss strategies for optimizing your conference
experience.  Issues to be discussed include: when and how to buy plane tickets, how to find roommates to keep down expenses, how to apply for conference support, how to navigate schedules with multiple sessions, and how to schedule interviews at conferences such as the Joint AMS Meeting.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f223ucehq0m4k7vvnj31chfej0","2010-10-11 11:33:31",NULL
"789","26","Supersonic Dispersive Fluid Dynamics, an Overview","2010-10-18 16:00:00",NULL,"SAS 4201","Mark Hoefer","http://www4.ncsu.edu/~mahoefer/","NC State",,,"The effects of supersonic fluid flow in gas dynamics are well known from common experience:  a sonic boom from a jet surpassing the speed of sound, the clap of thunder associated with a sudden increase in pressure and temperature from lightning, and the crack of a bullwhip, the first man-made implement to exceed the sound barrier.  The effects of supersonic flow in a dispersive fluid are, perhaps not so well known:  an undular bore in the Earth's atmosphere resulting from the collision of two air masses with different temperatures, surfable river waves resulting from a tidal surge with a supercritical Froude number less than 1.4, blast waves in a Bose-Einstein condensate generated by the application of a repulsive laser, and rapid oscillations in the electromagnetic field during propagation through a defocusing medium on top of a nonzero background.  The underlying mathematical differences and connections between these seemingly unrelated phenomena will be discussed in this overview of results and some future directions of research.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/grginesrob58nk39pbolto3cfg","2010-10-12 10:49:47","2010-10-12 10:50:01"
"790","8","Analysis of Discrete Models  of Biological Systems using Computer Algebra","2010-12-01 16:00:00",NULL,"SAS 4201","Franziska Hinkelmann",,"Virginia Bioinformatics Institute","Seth Sullivan",,"Many biological systems are modeled qualitatively with discrete models, such as probabilistic Boolean networks, logical models, bounded petri-nets, and agent-based models. Simulation is a common practice for analyzing discrete models, but many systems are far too large to capture all the relevant dynamical features through simulation alone. We convert discrete models into
algebraic models and apply tools from computational algebra to analyze the dynamics of discrete systems. The key feature of biological systems that is exploited by our algorithms is their sparsity: while the number of genes (or agents) in a biological network may be quite large, each gene is affected only by a small number of other genes. This allows for fast Groebner basis computations in the algebraic models, and thus efficient analysis. All algorithms and methods are available in our package Analysis of Dynamic Algebraic Models (ADAM), a `modeler friendly' web-interface that allows for fast analysis of large models, without requiring understanding of the underlying mathematics or any software installation.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8djh97t97mel2pvthst96hqmv8","2010-10-12 11:03:43","2010-11-23 12:32:00"
"791","7","Sparsity optimization and Robust estimation","2010-10-18 14:00:00",NULL,"SAS 4201","Kazi Ito","http://www4.ncsu.edu/~kito/","Mathematics, NC State","Min Kang",,"Many of applications including inverse problem, parameter estimation, filtering problem, deconvolution and inverse scattering problems, bionetworks, signal-image analysis and compression can be formulated as the regularized minimization problem. The regularization methodology based on the sparisity measure (numbers of nonzeros) is discussed and analyzed for such problems. A general mathematical formulation as well as numerical algorithms to solve a general class of sparsity optimization are discussed. Some numerical examples are also presented to demonstrate the capability and applicability of our approach.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ouehidj8ilnhk8j1nvh7sr4k4k","2010-10-12 17:34:38","2010-10-18 11:02:13"
"792","14","Departmental Tea and Cookies","2010-10-20 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sjaeskcrnudcmvbt8nqoi28c8s","2010-10-18 10:04:39",NULL
"793","14","Math TA Seminar: Classroom Management","2010-10-19 15:00:00",NULL,"SAS 2102",,,,,,"The second meeting will address Classroom Management.  Dr. Hoon Hong, will be the faculty member on the panel and Lindsey Bosko will give a lesson demonstrating classroom management techniques.  After which we will have discussion on other issues that were not addressed in the lesson.  Also, come with questions or issues that you have in your classroom and we can address them during the panel discussion.
 
Snacks will be provided.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i8lgts0g00arpqcta0a75j0ovs","2010-10-18 10:10:13",NULL
"794","2","Computational Fluid Dynamics Modeling in the Nasal Passages for Drug Delivery and Surgical Effects","2010-10-22 12:00:00",NULL,"142 Engineering Building III","Julia S. Kimbell",,"University of North Carolina School of Medicine",,NULL,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/s3ch8p9r4q8off5hcd66i31vtg","2010-10-18 10:25:33","2010-10-18 11:11:10"
"795","6","The Power System: A Complex System in Transition","2010-11-09 15:00:00",NULL,"SAS 4201","James S. Thorp","http://www.ece.vt.edu/faculty/thorp.php","Virginia Tech","Pierre Gremaud",,"The fact that a simple model of a power system could behave chaotically was established in 1982. Since then bifurcations, fractals, and power law behavior have been observed in model systems and in the field. The mechanism of cascading outages and the inevitability of blackouts will be examined in this context. One conclusion from this is that we have essentially the same power system we had in 1965. The modernization of the nation's transmission system using synchronized sampling using GPS is being adopted worldwide and will have significant impact on the security and reliability of the grid. The technique and some of the applications that are being funded will be described. ","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dkte9v27fm95ae1vg6e5omh35s","2010-10-20 09:20:18","2010-11-04 15:09:24"
"796","23","Introduction to High Performance Computing (HPC) at NCSU","2010-10-22 15:00:00",NULL,"SAS 4201","Gary Howell",,"NC State",,,"North Carolina State University has substantial resources dedicated to High Performance Computing (HPC) including several thousand processors that are available through the NCSU Blade Center.  Today's RTM will provide an introduction to these resources and provide attendees with initial information about how to get access to the facilities.   Attendees do not need to have an HPC account.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8oi2m453q71nn5lpo9l3ke4ov8","2010-10-20 15:56:45",NULL
"797","26","Algebraic multigrid methods for inhomogeneous elastic inclusion problems in articular cartilage","2010-10-25 16:00:00",NULL,"SAS 4201","Zhengzheng Hu","http://www4.ncsu.edu/~zhu4/Zhengzheng/Welcome.html","NC State Mathematics Postdoc",,,"In this talk, algebraic multigrid (AMG) methods tailored to simulating inhomogeneous elastic deformation in the biomechanical microenvironment of the cells in articular cartilage are presented based on use of the finite element method. To assess performance of the AMG methods, a radial analytical solution for a circular inclusion is developed based on a prescribed level of apparent strain.  Numerical results are evaluated using the analytical solution to demonstrate accuracy and efficiency of the computational modeling approach over typical ranges of material parameters for articular cartilage. ","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fvmq2di7ovt3743eiue7ukmtis","2010-10-22 08:51:11",NULL
"798","19","Analogs of the Frattini Subalgebra","2010-10-25 15:30:00",NULL,"SAS 2235","Kristen Stagg",,"NC State Mathematics Graduate Student",,,"Generalizations and analogs of the Frattini subgroup have been studied in various articles. This talk will develop analogs of the Frattini subalgebra in Lie algebras. Specifically, we will show characterization by non-generators, containment relations, and nilpotency.","edbancro","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h06ojhufjk7msdpm2j2a9dc0m8","2010-10-24 15:09:41",NULL
"799","9","A mathematical model for the mucosal immune response (Wanner) and A test for type of synaptic noise in the Fitzhugh-Nagumo neuronal model (Smith)","2010-10-28 16:00:00",NULL,"Cox 400","Nathan Wanner and Charles Smith",,"NC State Biomathematics","Kevin Gross",,,"krgross","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a2eql6n4aqjbugdgdtb9nflj7o","2010-10-25 16:27:04",NULL
"800","9","Generalized sensitivity functions for delay differential equation models (Robbins) and Predicting arterial flow and pressure dynamics using a 1D fluid dynamics model coupled with a generalized viscoelastic wall model (Olufsen)","2010-11-11 16:00:00",NULL,"Cox 400","Danielle Robbins and Mette Olufsen","http://www4.ncsu.edu/~msolufse/","NC State Biomathematics","Kevin Gross",,,"krgross","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3qft6v26lab1ag29nvr3kevfp4","2010-10-25 16:28:25","2010-11-09 10:08:13"
"801","9","Multiple infection dynamics of plant viral diseases: Barley yellow dwarf virus as a model system (Lyzinski)  and  Fighting fire with fire: Can we use mosquitoes to combat mosquito-borne disease? (Lloyd)","2010-12-02 16:00:00",NULL,"Cox 306","Becky Lyzinski and Alun Lloyd",,"NC State Biomathematics","Alun Lloyd",,,"krgross","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kbggkvqumlu4gh50ebgq6r3cgs","2010-10-25 16:29:13","2010-11-29 11:46:18"
"802","14","Departmental Tea and Cookies","2010-10-26 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2ar2jh4o1licunp3um151mstpo","2010-10-25 20:22:27",NULL
"803","26","Comparison of Optimal Design Methods for a Glucose Regulation Model","2010-11-01 16:00:00",NULL,"SAS 4201","Kathleen Holm",,"NC State Mathematics Graduate Student",,,"Optimal design methods for inverse problems are designed to choose an optimal sampling distribution through the minimization of a specific cost function related to the resulting error in the parameter estimates. It is hoped that the inverse problem will produce parameter estimates with increased accuracy using data from the optimal sampling distribution. Three different optimal design methods will be introduced: D-optimal, E-optimal and SE-optimal design. These optimal design methods will be compared based on the parameter estimates and standard errors resulting from the inverse problem with data from the optimal sampling distribution. The comparison of the optimal design methods will be illustrated for a popular glucose regulation model.  We will introduce another glucose regulation model and describe future modeling work.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6bgsg5tfiqshg5f4dtgqkp1a7o","2010-10-28 08:44:11",NULL
"805","4","Low-Mach-Number Compressible Euler Equations with Solid-Wall  Boundary Condition and General Initial Data","2010-12-01 15:00:00",NULL,"SAS 4201","Bin Cheng","math.asu.edu/~cheng","Arizona State University","Alina Chertok",,"We prove that the divergence-free component of the solution of the compressible Euler equations with solid-wall boundary condition converges strongly towards its incompressible counterpart as the Mach number approaches zero. The major analytical and numerical challenge is that,  in the compressible solution, large-amplitude fast oscillations (acoustic waves) exist initially and, in a bounded domain, persist permanently. I will address this issue without filtering the initial data. The computational implication of this study is open, and I will be happy to have it discussed if time permits.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v8bep047bm5k3ejaj3t56f0cf4","2010-10-28 17:08:49","2010-11-12 11:32:53"
"806","22","Counting, coloring... and calculus?","2010-11-10 16:00:00",NULL,"SAS 2102","Erin Bancroft","http://www4.ncsu.edu/~eelukasi/index.shtml","NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2010/111010.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tf60jajbdvhgs7m3gcjgme02t4","2010-10-29 15:34:53","2010-11-09 10:25:54"
"807","22","2?!?: Error Correcting for Quantum Computers","2010-11-17 16:00:00",NULL,"SAS 2102","Katie Liszewski",,"NC State",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/s2bcd9khjobemm01635eppeg2k","2010-10-29 15:35:39","2010-11-10 10:41:40"
"808","19","Shard Intersections in S_n as Permutation Pre-orders","2010-11-01 15:30:00",NULL,"SAS 2235","Erin E. Bancroft","http://www4.ncsu.edu/~eelukasi/index.shtml","NC State Mathematics Graduate Student",,,"Shards were introduced to give a geometric description of lattice congruences of the weak order in terms of the polyhedral geometry of the reflecting hyperplanes of a finite Coxeter group W. The shard intersection order is a new lattice structure on W which was used to give a new proof that the noncrossing partition lattice NC(W) is a lattice. In this talk we will consider the case where W is the symmetric group S_n. We define a bijection between shard intersections and certain pre-orders which we call permutation pre-orders. We use this combinatorial characterization to determine properties of the shard intersection order. In particular, we give an EL-labeling. We conclude by classifying a subset of permutation pre-orders which correspond to noncrossing partitions.","edbancro","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9miflt60r1nu6p9tcoc2to634c","2010-10-31 00:05:50","2010-10-31 14:30:33"
"809","8","Integration of Liouvillian Functions","2010-11-17 16:00:00",NULL,"SAS 4201","Clemens Gunter Raab",,"Johannes Kepler University, Linz Austria","Michael Singer",,"We will outline a decision procedure for integrating
transcendental Liouvillian functions based on the Risch-algorithm.
Applications to parameter integrals will be discussed along with examples.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9of7fag7u8hd11pmlieb8tplc4","2010-10-31 21:53:41","2010-11-10 09:23:46"
"810","21","TA Grading Party","2010-11-01 17:30:00",NULL,"SAS 4104",,,,,,"A dinner of chili, cornbread, salad, and cookies will be provided.  Please encourage your graders and TAs to attend as it is a great opportunity to get together with other TAs in the class and department to grade. 

Faculty and instructors, please extend this opportunity to your undergrad graders and TAs who are not in the math department. ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6iuobc0vucj522pkpsk8bgc6ac","2010-11-01 10:12:20",NULL
"811","28","WM Lunch Seminar: How to Choose an Advisor","2010-11-03 12:30:00",NULL,"SAS 4201",,,,,,"Association for Women in Mathematics will be hosting a lunch seminar addressing the important task of choosing a Ph.D. advisor.  A diverse panel of graduate students will discuss their experiences and address questions such as:  When should I get an advisor?  How do I ask a professor to be my advisor?  How do I know my advisor and I will work well together?  What if I think I need to switch advisors?  How do I ask for funding from my advisor?

All graduate students are invited to attend.  Lunch will be provided.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/aendk4p1eeng125m486lc577ik","2010-11-01 10:15:27",NULL
"812","14","Departmental Tea and Cookies","2010-11-05 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/g45e0alfmp8uvn14cmibb1419k","2010-11-02 14:20:58",NULL
"813","4","Continuations of the nonlinear Schrodinger equation beyond the singularity","2011-02-09 15:00:00",NULL,"SAS 4201","Gadi Fibich","http://www.cs.tau.ac.il/~fibich","Tel Aviv University","Semyon Tsynkov",,"The nonlinear Schrodinger equation (NLS) is one of the canonical nonlinear equations in physics. In 1965, Kelley showed that the NLS admits solutions that collapse (become singular) at a finite time (distance). Since physical quantities do not become singular, a question, which has been open since 1965, is whether and how singular NLS solutions can be continued beyond the singularity.

A similar situation occurs in hyperbolic conservation laws, where in the absence of viscosity, the solution can become singular (develop shocks). In that case, there is a huge body of literature on how to continue the inviscid solution beyond the singularity. In contrast, only two studies addressed this question for the NLS.

In this talk I will present three novel continuations of the NLS beyond the singularity. The three continuations share the universal feature that after the singularity, the solution is only determined up to multiplication by a constant phase term. As a result, the interaction between two post-collapse components (beams) is chaotic.

Joint work with M. Klein.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vetlic8e7j3pobhgmm3tnmabuk","2010-11-03 09:09:33","2010-12-02 10:23:58"
"814","11","Financial crisis of 2008","2010-11-05 13:30:00",NULL,"SAS 4201","Janet Cowell","http://www.nctreasurer.com/dsthome/OfficeOfTheTreasurer/Biographical","State Treasurer",,,"The Treasurer's presentation will focus on the financial crisis of 2008 and the spotlight it has cast on public funds. The Treasurer's remarks will take roughly 20-25 minutes and she will be available afterwards for Q&A and interaction for about 20-30 minutes.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k2m3ti37tq05pnum0164g73bhs","2010-11-04 14:12:28","2010-11-05 10:19:57"
"815","26","A Quadratic Binary Programming Problem,  Modeling and Linearization Techniques","2010-11-08 16:00:00",NULL,"SAS 4201","Tulay Ayyildiz Akoglu",,"NC State Mathematics Graduate Student",,,"Let G be a graph and w be a weight function. Given a hereditary property, the maximum hereditary induced subgraph problem consists of finding an induced subgraph of G which satisfies a hereditary property and is of maximum weight. 
This problem can be modeled as a quadratic binary programming problem. The model can be linearized by using standard linearization techniques, therefore it can be solved in polynomial time. Moreover, a new linearization method for the problem is generalized to the maximum hereditary induced subgraph problem when no specific hereditary property is considered. ","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1fofrge0hvr95jl61uo3r74m5k","2010-11-08 08:55:52",NULL
"816","23","Interview Do's and Don'ts","2010-11-12 15:00:00",NULL,"SAS 4201","Departmenal Faculty",,"North Carolina State University","Ralph Smith",,"What type of presentation should you give and what do you do if you cannot answer a question? Should you try to negotiate salary or benefits during the initial interview?  Is it appropriate to have your mother call the search committee for any reason?  What do you do if your cell phone rings during the interview?  What do you do if you are late for the interview and how should you dress?

These questions and others will be discussed during this week's RTM.  This session should be of interest to all students and postdocs presently looking for a job.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f0m7vgv7ugbd7odsge3dak4als","2010-11-08 11:59:43","2010-11-08 12:02:32"
"817","23","Poster Design","2010-11-19 15:00:00",NULL,"SAS 4201","Billy Tallis",,"North Carolina State University","Ralph Smith",,"Posters comprise an increasingly popular medium to disseminate research at conferences and workshops and are becoming required at certain meetings.  However, the design of effective posters differs significantly from that of research talks.  The speaker will discuss techniques pertaining to highly effective poster design and construction using pages, PowerPoint and LaTeX.  In addition, there will be general discussion regarding the layout of effective posters.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v1uc2fqnql0jg9roj3joch09mg","2010-11-08 12:04:59",NULL
"818","14","Departmental Tea and Cookies","2010-11-09 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ebtlojcsl5mau1e8cs4oi6vq70","2010-11-08 14:14:01",NULL
"819","7","Coalescence in Branching Trees","2010-11-23 11:00:00",NULL,"SAS 4201","Krishna Athreya","http://orion.math.iastate.edu:80/kba/","Iowa State University","Min Kang",,"In a growing family tree choose two individuals from the nth generation and trace their lines of descent back in time till they meet. Call that generation Xn. In this talk we study the distribution of Xn and its limit as n goes to infinity for Galton Watson trees.
This talk will be self contained. Results from branching processes will be reviewed first. It will be accessible to graduate students.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hbp2huf27qrb51h00ivdiqg5ss","2010-11-09 19:07:43","2010-11-17 18:33:37"
"820","6","Uncertainty Analysis for Complex Systems: Algorithms beyond Polynomial Chaos","2011-02-08 15:00:00",NULL,"SAS 4201","Dongbin Xiu","http://www.math.purdue.edu/~dxiu/","Purdue","Pierre Gremaud",,"The field of uncertainty quantification has received increasing amount of attention recently. Extensive research efforts have been devoted to it and many novel numerical techniques have been developed. These techniques aim to conduct stochastic simulations for large-scale complex systems. In this talk we will review one of the most widely approaches -- generalized polynomial chaos (gPC). The gPC methods employ orthogonal polynomials in random space and take advantage of the solution smoothness (whenever possible). The features of various gPC numerical schemes will be reviewed. Furthermore, we will discuss some of the highly efficient algorithms that are based on gPC and effective for simulations beyond uncertainty propagation. These algorithms are applicable for problems such as inverse inference, data assimilation, reliability analysis, etc.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fitlcae59esat4k61vk2bil3v0","2010-11-12 16:52:29","2011-01-28 13:23:01"
"821","21","Putnam Math Competition","2010-12-04 10:00:00",NULL,"SAS 2106",,,,,,"We need you to find talented undergraduate  students to join our NCSU math competition team.  If you teach undergraduate course and if you know anyone in your class who might be interested in participation, please tell them about the Putnam competition. Since I could not send email to ALL NCSU UNDERGRADUATES,  you are the only channel to tell our students  about the Putnam.

The Putnam competition has two sessions:  from 10:00am - 1:00 pm (morning session) and from 3:00-6:00 pm (afternoon session) in SAS2106.  Walk-in registration starts 15 minutes  before the competition.  All undergraduate students are eligible to participate.

Student who gets  the  highest score in  NCSU   receives a cash prize.  Top 500 finish nationwide will have  their names published in AMS magazine.  Besides it helps to  bright up the resume by simply joining our math competition team. For more information or to obtain practice problems, contact Dr. Lin at xblin@math.ncsu.edu","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ubkpjcrvc7fu0o41ofb0bups0o","2010-11-15 10:21:30",NULL
"822","1","Estimating ultra-large phylogenies and alignments","2010-12-03 15:00:00",NULL,"SAS 4201","Tandy Warnow","http://www.cs.utexas.edu/~tandy","Department of Computer Sciences, University of Texas at Austin","Loek Helminck",,"Biomolecular sequences evolve under processes that include substitutions, insertions and deletions (indels), and other events, such as duplications.  The estimation of evolutionary history from sequences is used to answer fundamental questions about biology, and also has applications in a wide range of biomedical research areas.  

From a computational perspective, phylogenetic (evolutionary) tree estimation is enormously hard: all standard approaches are NP-hard or have sequence length requirements that grow exponentially in the maximum evolutionary distances.  Empirical studies of existing methods also show that large datasets are enormously difficult, taking in many cases weeks or months of analysis.

In this talk I will present several methods that greatly improve the accuracy of phylogeny estimation methods.  These methods utilize divide-and-conquer strategies in order to improve the accuracy of traditional phylogeny estimation methods.  For example, I will present one method and prove that it is guaranteed to reconstruct  the true tree from polynomial-length sequences under the General Time-Reversible model for sequence evolution.  I will also describe  SATe (Liu et al. 2009, Science vol. 324, no. 5934).  SATe simultaneously estimates a tree and alignment, and our study shows that it produces dramatically more accurate trees and alignments than competing methods, even on datasets with 1000 taxa and high rates of indels and substitutions.  I will also describe our new method, DACTAL (not yet submitted).  DACTAL stands for  ""Divide-and-Conquer Trees without Alignments.""  Our study, using both real and simulated data, shows that DACTAL produces trees of higher accuracy than SATe, and does so without ever constructing an alignment on the entire set of sequences.  Furthermore, DACTAL is extremely fast, producing highly accurate estimates of datasets in a few days that take many other methods years.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/6virufv50u18ufku8dhcoc34bc","2010-11-15 14:35:14","2010-11-23 10:11:31"
"823","14","Pre-Thanksgiving social for faculty, graduate students, and staff","2010-11-19 14:00:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3bh5rq8fjb8t2b1tdted7lfl78","2010-11-16 09:52:12","2010-11-16 09:53:14"
"824","21","Triangle Lectures in Combinatorics","2011-04-09 09:15:00",NULL,"NC State Campus SAS 1102",,,,,"http://www.math.ncsu.edu/TLC/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pvjgv8ktn1b85s51lqergnqddc","2010-11-16 09:55:40","2011-04-04 09:56:14"
"825","26","Visualization and Grid Modification of Evolving Landforms Due to Sea-Level Rise","2010-11-22 16:00:00",NULL,"SAS 4201","Elisabeth Brown",,"NC State Mathematics Graduate Student",,,"The North Carolina Coastal Resources Commission has adopted one-meter sea-level rise (SLR) as a planning number. One-meter of SLR will have significant impact on the Outer Banks of North Carolina. Fundamental methodologies to model sea-level rise using raster and vector based datasets in order to underpin conventionally modeled metrics of storm hazard are not readily available in a three dimensional (3D), high resolution digital format. Given the 3D complexity of the topography and bathymetry (topobathy) of the Outer Banks, visualizing changing water levels and land configurations is not always intuitive. Geographic Resources Analysis Support System Geographical Information System (GRASS GIS) provides a ready environment for the masses of population visualize, in three-dimensions, topobathy which have been altered using well-known theoretical approaches. The first step is to hydraulically flood the 10-m North Carolina topobathy. Secondly, raster-based methodologies are explored through the use of the Bruun Rule, a conservation of volume model that predicts migration/recession due to sea-level rise. Striking but realistic visualizations of geomorphic change using the Bruun Rule occur as a result of discontinuous soundside features. Application of the Barrier Island Bruun Rule in the location of the 2003 Hurricane Isabel Breach picks up these discontinuities and predicts a break in the island. While storm processes are not modeled in the Bruun Rule, this break suggests a strong geomorphic relationship to the location of the Breach. As a third step, Tangible GIS was used to recreate New Inlet bathymetry as it existed in the 1940s. The resulting altered topobathy raster elevation data from New Inlet was then used to modify node values for a process-based numerical grid model ADCIRC. Raster and vector based techniques in a flexible computational environment such as GRASS allow exploration of geomorphic changes due to SLR.
","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ch2c5uafgjij7jcrucmflsihi8","2010-11-19 11:13:21",NULL
"828","14","Fourth Grading Party","2010-11-22 17:30:00",NULL,"SAS 4104",,,,,,"Just wanted to let everyone know that the fourth (and last) grading party is this Monday, November 22 at 5:30PM in the Math Commons on the fourth floor of SAS.  Dinner will be provided and after dinner there will be plenty of time to grade (tests or quizzes).  Also, if you do not have grading yet, please feel free to come by and get some dinner.  PLEASE forward this message on to your graders if they are undergraduates or not in the math department.  This is a great place for them to get together, eat some dinner, and do some grading, especially if you teach one of the classes with several graders.

Dinner at this grading party will be pizza, cookies, and soda!","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bctvdmnhdrpjf2i772a4tgtt6g","2010-11-22 09:34:57",NULL
"829","14","Departmental Tea and Cookies","2010-12-03 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7br0jng9so9p6krrhv6rea6u4s","2010-11-23 10:01:36",NULL
"830","1","What we eat matters: Resource quality dynamics and its implications","2011-01-28 16:00:00",NULL,"SAS 4201","Yang Kuang","http://math.asu.edu/~kuang","Arizona State University","H. T. Banks",,"Mathematical biologists have built on variants of the Lotka--Volterra equations and in almost all cases have adopted the pure physical sciences' single-currency (energy) approach to understand population dynamics. However, biomass production requires more than just energy. It is crucially dependent on the chemical compositions of both the consumer species and food resources. In this talk, we explore how depicting organisms as entities of more than one thing (for example, C and a limiting nutrient, such as P) in stoichiometrically explicit models results in qualitatively different and realistic predictions about the growth dynamics. Stoichiometric models incorporate both food quantity and food quality effects in a single framework, appear to stabilize producer-consumer systems while simultaneously producing rich dynamics with alternative domains of attraction and counterintuitive outcomes, such as coexistence of more than one predator species with a single prey and decreased herbivore performance in response to increased plant growth rate. Stoichiometric theory has tremendous potential for both quantitative and qualitative improvements in the predictive power of mathematical models in the study of disease evolution and treatment dynamics.
","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/t78v3ccpnbbvpanif136cq5jgo","2010-11-23 10:19:40","2011-01-25 10:16:38"
"831","14","Honor's Program Research Presentations","2010-12-01 16:00:00",NULL,"SAS 2102",,,,,,"1. Zach Clawson -- Domain Restriction Techniques for Single-source/single-target Optimal Trajectory Problems

2. Aaron Marcus  -- Improved Methods for Analyzing Nonlinearity in the Spring Equation  

3. Wesley Springs  --  An Analysis of Alliances, Strategies, and Solutions in Three-player Games  ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/eub89ik857e4qisbbsstuvj574","2010-11-30 15:19:21",NULL
"832","14","Honor's Program Research Presentations","2010-12-02 12:30:00",NULL,"SAS 4201",,,,,,"1. Becky Maust  -- Describing Group Representations using Characters  

2. John Hanna  -- Integer Partitions  

3. Mike Schuster  -- Generalized Lecture Hall Partitions   ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ln40qakpb55gjcguc8qbim09eg","2010-11-30 15:20:12",NULL
"833","14","Math TA Seminar: How to balance students/professors/grading with your own finals!","2010-12-06 14:30:00",NULL,"SAS 4201","Dr. PJ Adams",,"NC State",,,"With the onslaught of student emails begging extra tutoring, extra credit opportunities, demanding to know their grade immediately, etc, etc, etc hitting at the same time as you all begin to study for your own finals stress is certain to happen!  On Monday, we will be discussing how to politely handle all of the stress that comes from being a TA while studying and taking your own finals as well.  Dr. PJ Adams from the Counseling Center will be joining us to give us tips on how to deal with stress and how to address these problems.  As always, there will be snacks!  Take a break from your studying to come get a snack and hear some tips for the next two weeks!

The seminar will be Monday Dec 6 2:30-3:30 in SAS 4201.  We'll see you there!","klstagg","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ivaf2nqrnna0031knrf59s4dd0","2010-12-03 14:14:42",NULL
"834","2","Cloaking via change of variables for the Helmholtz equation","2011-01-18 15:00:00",NULL,"SAS 4201","Hoai-Minh Nguyen","http://cims.nyu.edu/~hoaiminh/","Courant Institute",,,"A region of space is cloaked for a class of measurements if observers are not only unaware of its contents, but also unaware of the presence of the cloak using such measurements. One approach to cloaking is the change of variables scheme introduced by Greenleaf, Lassas, and Uhlmann for electrical impedance tomography and by Pendry, Schurig, and Smith for the Maxwell equations. They used a singular change of variables which blows up a point into the cloaked region. To avoid this singularity, various regularized schemes have been proposed. In this talk I present results related to cloaking via change of variables for the Helmholtz equation using the natural regularized scheme introduced by Kohn, Shen, Vogelius, and Weintein, where the authors used a transformation which blows up a small ball instead of a point into the cloaked region. I will discuss the degree of invisibility for a nite range or the full range of frequencies, and the possibility of achieving perfect cloaking. At the end of my talk, I will also discuss some results related to the wave equation in 3d.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/54amumsrhqn0jpjgjqv32skg0g","2010-12-08 09:02:48","2010-12-21 10:50:33"
"835","14","Departmental Tea and Cookies","2010-12-08 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kpuk9mniclafnpodgotiankk5k","2010-12-08 10:15:40",NULL
"837","6","Sinking, merging and stationary plumes in a coupled chemotaxis-fluid model: a high-resolution numerical approach","2011-03-22 15:00:00",NULL,"SAS 4201","Alina Chertock","http://www4.ncsu.edu/~acherto/","NC State Mathematics",,,"Aquatic bacteria like Bacillus subtilis are heavier than water yet they are able to swim upwards an oxygen gradient and concentrate in a layer below the water surface, which will undergo Rayleigh-Taylor type instabilities for sufficiently high concentrations. Recently, a simplified chemotaxis-fluid system has been proposed as a model for modestly diluted cell-suspensions. It couples a convective chemotaxis system for the  oxygen-consuming and oxyotactic bacteria with the incompressible Navier-Stokes equations subject to a gravitational force proportional to the relative surplus of the cell-density compared to the water-density.

In this talk, I will present a high-resolution vorticity-based hybrid finite-volume finite-difference scheme, which allows to investigate the nonlinear dynamics of a two-dimensional chemotaxis fluid system. In particular, I will show selected numerical examples, which illustrate (i) the formation of sinking plumes, (ii) the possible merging of neighboring plumes and (iii) the convergence towards numerically stable stationary plumes. The examples with stable stationary plumes show how the surface-directed oxyotaxis feeds continuously cells into a high-concentration layer near the surface, from where the fluid-flow (recurring upwards in the space between the plumes) transports the cells into the plumes, where then gravity makes the cells sink and constitutes the driving force in maintaining the fluid-convection and, thus, in shaping the plumes into (numerically) stable stationary states.

Joint work with K. Fellner, A. Kurganov, A. Lorz and P. Markowich. ","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pkavsn0eec0gtf87rtvfsohehg","2010-12-08 11:10:14","2011-02-21 13:11:24"
"838","6","TBA","2011-01-02 15:00:00",NULL,"SAS 4201","Gary Howell","http://www.ncsu.edu/itd/hpc/Documents/Publications/gary_howell/contents.html","NCSU, Office of Information of Technology",,,,"ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/95e3qfnibkkv22qi4n04sulq90","2010-12-09 10:30:37","2011-01-16 11:06:57"
"839","14","Departmental Tea and Cookies","2011-01-18 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6i56v4jtelnit0qne9iv0qm58k","2010-12-09 14:01:31",NULL
"840","14","Departmental Tea and Cookies","2011-01-12 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gu1fge87i3754duim5h3ojd2bc","2010-12-09 14:01:58",NULL
"841","14","Departmental Tea and Cookies","2011-01-20 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8danc5deot840v094kha74vkqk","2010-12-09 14:02:21",NULL
"842","14","Departmental Tea and Cookies","2011-01-13 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hao2cpefq7h816i0ag54c8nvsk","2010-12-09 14:03:59",NULL
"843","14","Departmental Tea and Cookies","2011-01-14 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/04qvn856vsfbpj7ift4q6sfnt4","2010-12-09 14:05:02",NULL
"844","14","Departmental Tea and Cookies","2011-01-19 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i9eph58ipaqhglod0ujiosmcik","2010-12-09 14:05:27",NULL
"845","14","Departmental Tea and Cookies","2011-01-11 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3bnlov5c946ulp8bea2shr0v3c","2010-12-09 14:05:55",NULL
"846","14","Departmental Tea and Cookies","2011-01-24 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5gc7037ohol02l5dvrlrr2vfo0","2010-12-09 14:06:43",NULL
"847","14","Departmental Tea and Cookies","2011-01-28 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/4sg0fap575pf7qoce4d1uv2m7s","2010-12-09 14:07:04","2011-01-24 14:21:33"
"848","2","Nonnegative Polynomials and Sums of Squares","2011-01-18 16:00:00",NULL,"SAS 4201","Grigoriy Blekherman","http://sites.google.com/site/grrigg/","Institute for Pure and Applied Mathematics, UCLA",,,"A multivariate real polynomial $p$ is nonnegative if $p(x)  \geq 0$ for all $x \in R^n$. I will review the history and motivation behind the problem of representing nonnegative polynomials as sums of squares. Such representations are of interest for both theoretical and practical computational reasons. I will present two approaches to studying the differences between nonnegative polynomials and sums of squares. Using techniques from convex geometry we can conclude that if the degree is fixed and the number of variables grows, then asymptotically there are significantly more nonnegative polynomials than sums of squares. For the smallest cases where there exist nonnegative polynomials that are not sums of squares, I will present a complete classification of the differences between these sets based on algebraic geometry techniques.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/otbiemlhkm76i50pboakr867a8","2010-12-09 14:59:25","2011-01-18 09:59:51"
"849","2","Image Restoration via Sparsity: Wavelet Tight Frame, Low Rank Matrix and Beyond","2011-01-12 15:00:00",NULL,"SAS 4201","Jian-Feng Cai","http://www.math.ucla.edu/~cai/","University of California, Los Angeles",,,"We are surrounded by data of various sources with different nature. In data processing, the internal structure of the data should be utilized. One of the most popular internal structures might be sparsity under suitable transforms.

In the first part of this talk, we focus on digital images, and their sparsity under a certain ftransform --- wavelet tight frames. To exploit the sparsity of images under wavelet tight frames, we derive three different formulations, namely, the analysis-based approach, the synthesis-based one, and the balanced one between them. The corresponding algorithms are then proposed. Besides that, theoretical results, including approximation property and connections to partial differential equation based image processing (e.g. Total Variation model), are discussed. Applications vary from image inpainting, deblurring, blind motion deconvolution, to cartoon-texture decomposition.

Then, the ideas are extended to the reconstruction of low-rank matrices, in which the sparsity is in its singular value domain. I will mainly present the singular value thresholding (SVT) algorithm for low-rank matrix completion, which is the first algorithm to deal with large scale matrix completion problem using convex optimization. Finally, we propose a new model which combines these two kinds of sparsities (sparsities under wavelet tight frame domain and singular value domain), and then the model is applied to solve 4D Computed Tomography image reconstruction in medical imaging.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/873u2nkn0jcgnha7sukfj3l9p0","2010-12-09 15:01:39","2011-01-04 15:02:47"
"850","2","Imatinib Dynamics and Cancer Vaccines: From Agent-Based Models to PDEs","2011-01-20 15:00:00",NULL,"SAS 4201","Peter Kim","http://www.math.utah.edu/~kim/","University of Utah",,,"Various models exist for the interaction between the drug imatinib and chronic myelogenous leukemia.  However, the role of the immune response during imatinib treatment remains unclear.  Based on experimental data, we hypothesize that imatinib gives rise to a brief anti-leukemia immune response as patients enter remission.

We propose that cancer vaccinations during imatinib treatment can boost the existing immune response and lead to a sustained remission or a potential cure.  To examine this hypothesis, we take a model by Michor et al. and extend it to a delay differential equation (DDE) model by incorporating an anti-leukemia immune response.  We show that properly-timed vaccines can sustain the immune response to potentially prolong remission or eliminate cancer.

For comparison, we analyze an agent-based model developed  independently by Roeder et al.  We develop a partial differential equation (PDE) model that captures the same behavior as the Roeder agent-based model and extend it by incorporating an immune response.  We conclude that both the DDE and PDE models exhibit similar behaviors with regard to cancer remission, implying that anti-leukemia immune responses may play a role in leukemia treatment.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dq8vt1pkij6ln2d8chpa8ee6q0","2010-12-09 15:03:41","2011-01-18 10:00:51"
"851","2","Compressive Sampling and Redundancy","2011-01-13 15:00:00",NULL,"SAS 4201","Deanna Needell","http://www-stat.stanford.edu/~dneedell/","Stanford University",,,"Compressive sampling (CoSa) is a new and fast-growing field which addresses the shortcomings of traditional signal acquisition. Many methods in CoSa have been developed to reconstruct a signal from few samples when the signal is sparse with respect to some orthonormal basis. This talk will introduce the field of CoSa and present new results in compressive sampling from undersampled data for which the signal is not sparse in an orthonormal basis, but rather in some arbitrary dictionary. We will highlight numerous applications to which this framework applies and interpret our results in these settings. Since the dictionary need not even be incoherent, this work bridges a gap in the literature by showing that signal recovery is feasible for truly redundant dictionaries. We show that the recovery can be accomplished by solving an &#8467;1-analysis optimization problem, and that the condition we impose on the measurement matrix which samples the signal is satisfied by many classes of random matrices. We will also show numerical results which highlight the potential of the &#8467;1-analysis problem.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dt1oca55bnf2do4ft98648i4oc","2010-12-09 15:04:51",NULL
"852","2","The Mathematics of Crime Hotspots","2011-01-14 15:00:00",NULL,"SAS 4201","Martin Short","http://www.math.ucla.edu/~mbshort/","University of California, Los Angeles",,,"Criminologists have often observed that crimes tend to form ""epidemic"" like spatio-temporal patterns, whereby criminal events seem to spawn further events in nearby space-time regions.  This often leads to the formation of crime hotspots, which are localized regions of intense criminal activity.  However, descriptive and/or predictive mathematical models of these hotspots have been lacking.  In this talk, I will describe two possible models for this phenomenon.  One starts from the bottom up, modeling some basic aspects of human criminal behavior and arriving at a set of PDEs reminiscent of others in the mathematical biology literature.  I will discuss some of the results and implications of the analysis of these PDEs, especially in terms of police response to hotspot formation.  The second model
starts from the top down, taking a data-driven statistical approach to the problem.  This method is closely related to others used in the modeling and prediction of earthquakes, and yields practical results that can help police to best utilize their limited resources.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vf5vumt6pp0g50gtrn9ttf6hm8","2010-12-09 15:06:02","2011-01-10 14:22:07"
"853","2","Equivariant Moving Frames, Lie Pseudo-Groups, and Local Equivalence Problems","2011-01-19 16:00:00",NULL,"SAS 4201","Francis Valiquette","http://www.math.mcgill.ca/valiquette/","McGill University in Montreal, Quebec",,,"The theory of equivariant moving frames is a new theoretical foundation to Cartan's moving frame method.  It is a powerful tool for studying geometric properties of submanifolds under the action of a group of transformations and their invariants.   In my talk, I will explain this new moving frame construction for infinite-dimensional Lie pseudo-group actions and show how it applies to local equivalence problems.  This will naturally lead us to the introduction of partial equivariant moving frames. To illustrate the theory and constructions I will solve the local equivalence problem of 3-webs in the Euclidean plane.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sviib6kq8j15mqcfnn09cf1vm4","2010-12-09 15:08:15","2011-01-10 10:01:01"
"854","2","Topological data analysis and the construction of intrinsic   circle-valued coordinates","2011-01-11 15:00:00",NULL,"SAS 4201","Mikael Vejdemo-Johansson","http://math.stanford.edu/~mik/","Stanford University",,,"A new research field has been materializing the last  decade, in which tools from algebraic topology are introduced to data  analysis and used to either unify previous knowledge or produce more  detailed, subtler, or more qualitative analysis tools. In this lecture, I will sketch out some of the tools studied at Stanford, and  then put focus on my own work on using persistent cohomology to  produce intrinsic circle-valued coordinate functions from finite,  discrete data sets. This, finally, will be used to provide a novel approach to the analysis and characterization of periodic signals and systems.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/chb046i709nspsvakfb44hk7vk","2010-12-09 15:11:04","2011-01-05 16:26:49"
"855","2","Nonlinear Wave Equations and Fluid-Structure Interactions","2011-01-19 15:00:00",NULL,"SAS 4201","Lorena Bociu","http://www.math.unl.edu/~lbociu2","University of Nebraska",,,"The talk will focus on the analysis and the in&#64258;uence of nonlinearities present in (i) wave equations and (ii) Navier-Stokes - elasticity interactions. In the case of the nonlinear wave equation, I will discuss the well-posedness of the system on &#64257;nite energy space. A distinct feature of the equation is the presence of the double interaction of supercritical sources and nonlinear damping terms, both in the interior of the domain and on the boundary. Moreover, the nonlinear boundary sources are driven by Neumann boundary conditions. Since Lopatinski condition fails to hold for dim(&#937;) &#8805; 2, the analysis of the nonlinearities supported on the boundary (within the framework of weak solutions) is a rather subtle issue and involves strong interaction between the source and the damping. I will provide positive answers to the question of Hadamard well-posedness and moreover give complete and sharp description of parameters corresponding to global existence and blow-up of solutions in &#64257;nite time. For the nonlinear coupling of Navier-Stokes - elasticity, I will present a completely new linearization, derived in view of the stability analysis. The linearization reveals the presence of the curvature on the common interface, which demonstrates that the free boundary plays a key role in the analysis of the coupled system and its in&#64258;uence can not be neglected. 
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/14qkqju2bcrlit3lllit154hu4","2010-12-09 15:13:14","2011-01-18 09:59:13"
"856","2","Boundary effects in kernel approximation and the polyharmonic Dirichlet problem","2011-01-12 16:00:00",NULL,"SAS 4201","Thomas Hangelbroek","http://www.vanderbilt.edu/math/people/hangelbroek","Vanderbilt University",,,"Boundary effects pose a frequent challenge in approximation theory. In this regard, kernel approximation --  a methodology for approximating in high dimensions, on manifolds, and in settings with cumbersome geometry -- is no exception.  The negative influence of the boundary is well-understood theoretically and is easily observed numerically.  By exploiting a potential theoretic integral representation, a new kernel approximation technique delivers theoretically optimal (and previously unrealized) convergence rates by isolating the boundary effects in easily managed integrals.

In this talk I will give a brief introduction to kernel approximation and the pathology of the boundary, as it  relates to convergence rates of known approximation techniques.  After this I will discuss  the new approximation scheme, how it succeeds, and the boundary layer potential solution of the polyharmonic Dirichlet problem.  This is the key to establishing the integral representation at the center of the scheme.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ju7bhgd3pk88ut74q7cr8r2j1s","2010-12-09 15:14:55","2011-01-10 10:05:00"
"857","2","PDE stability problems on unbounded domains","2011-01-20 16:00:00",NULL,"SAS 4201","Alin Pogan","http://www.math.umn.edu/~pogan007/","University of Minnesota",,,"The subject of this talk is at a crossroad of Analysis, PDEs, Dynamical Systems and Applied Mathematics. We will discuss new methods in stability analysis of special solutions of PDEs such as spikes and waves on in&#64257;nite domains. A &#64257;rst step in the stability analysis of localized patterns typically consists of the analysis of linearized stability. The two major di&#64259;culties in the stability analysis are the structure of the domain and the presence of eigenvalues of the linearization at the edge of the essential spectrum. In this talk I will illustrate how to overcome these two di&#64259;culties for two important classes of problems. 

The &#64257;rst class that we consider is the case of nonlinear reaction di&#64256;usion equations coupled to a conservation law on R or Rn . The linearization of such a system about a spike solution always has an eigenvalue at the edge of the essential spectrum. We use the Lyapunov-Schmidt reduction method on exponentially weighted spaces to solve the eigenvalue problem near the essential spectrum. Finally, we use the parity index method to settle the stability/instability problem of spike solutions. 

Another interesting class of problems appears is the study of certain nonlinear systems on in&#64257;nite cylinders. To track the eigenvalues positioned away from the essential spectrum, we construct an analytic function on the complement of the essential spectrum, called the Evans function, whose set of zeros coincides with the point spectrum of the linearization. In the case of systems on in&#64257;nite cylinders, we show that the Evans function can be constructed via a modi&#64257;ed in&#64257;nite determinant of generalized Jost solutions.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pdgjpb9okac2083fe3oqcg2v00","2010-12-09 15:18:20","2011-01-04 11:13:41"
"858","2","Large-Time Behavior Of Solutions Of Semilinear Dispersive Equations","2011-01-14 16:00:00",NULL,"SAS 4201","Tristan Roy","www.cims.nyu.edu/~troy","Courant Institute, New York University",,,"In this talk we give an overview of the existing methods to study global well-posedness of solutions of some semilinear dispersive equations.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/br25m74unpo1n2md3hjj4pq15g","2010-12-09 15:20:50","2011-01-04 10:56:00"
"859","1","Symbolic computing in modeling and simulation","2011-03-25 16:00:00",NULL,"SAS 1102","Laurent Bernardin","http://bernardin.com","Executive Vice-President and Chief Scientist, Maplesoft","Erich Kaltofen",,"Modeling and simulation of a physical system are crucial steps in the engineering design process. New challenges such as hybrid and electric vehicles, alternative energy systems, autonomous probes, and humanoid robots require simulation models of rapidly increasing complexity. 

Acausal modeling approaches allow engineers to express physical systems with a high-level description, which allows very complex models to be developed quickly. However, the resulting systems of equations that describe the system behavior cannot be directly solved numerically as they typically are very large, overconstrained, high-index DAEs. 

This talk will give an overview of the state of the art in this area and show how symbolic techniques are essential to simplify these systems of equations, reduce the differential index, eliminate redundancies, and generate optimized code that can then be simulated with a numeric differential equation solver.

We will also provide real-world benchmarks that show significant speedups when comparing such a symbolic approach with traditional numeric techniques.

The presentation will conclude with the discussion of open research problems.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/rm5oopopij9dvluumane3f6ajk","2010-12-16 10:57:16","2011-03-14 12:00:47"
"860","4","Interaction manifolds in reaction-diffusion systems","2011-02-23 15:00:00",NULL,"SAS 4201","Douglas Wright","http://www.math.drexel.edu/~jdoug/","Drexel University","Steve Schecter",,"We consider a general reaction-diffusion equation with a localized traveling-wave solution.  Under assumptions no stronger than those needed to prove the stability of a single pulse, we prove that the PDE has solutions that are roughly the linear superposition of two pulses. In particular we prove that if the initial data for the equation is close to the sum of two separated pulses, then the solution converges exponentially fast to such a superposition, as long as the distance between the two pulses remains sufficiently large.  The work presented was done in collaboration with Aaron Hoffman and Arnd Scheel.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ipv3011vrrnlh7nbtjvvsq72q0","2010-12-16 11:08:22","2011-02-18 10:52:36"
"861","6","ReALE – Reconnection-based Arbitrary Lagrangian Eulerian Method","2011-04-12 15:00:00",NULL,"SAS 4021","Mikhail Shashkov","http://cnls.lanl.gov/~shashkov/","Los Alamos National Laboratory","NA Seminar; NE dept",,"We present a new reconnection-based  multi-material Arbitrary Lagrangian Eulerian  (ALE) method [1,2].  The main elements in an standard ALE simulation are an explicit Lagrangian phase in which the solution and grid are updated, a rezoning phase in which a new grid is defined, and a remapping phase in which the Lagrangian solution is transferred (conservatively interpolated) onto the new grid.

In standard ALE methods the new mesh from the rezone phase is obtained by moving grid nodes without changing connectivity of the mesh. Such  rezone strategy has its limitation due to the fixed topology of the mesh.  In our new method we allow connectivity of the mesh to change in rezone phase, which leads to general polygonal mesh and  allows to follow Lagrangian features of the mesh much better than for standard ALE methods.

Rezone strategy with reconnection is based on using Voronoi tessellation. Mesh smoothing is achieved by using notion of centroidal Voronoi diagrams. Because of reconnection we have to use discretizations of Lagrangian hydro, which are capable to deal with general polygonal mesh. In this work we use both cell-centered and staggered discretizations on general polygonal meshes. For remapping stage we use algorithms based on intersections of Lagrangian and rezoned mesh. 

We demonstrate performance of our new method on series of numerical examples and show it superiority and robustness in comparison with standard ALE methods without reconnection.

REFERENCES
[1]	R. Loubere et al., ReALE:  A Reconnection-based Arbitrary Lagrangian-Eulerian Method, J. Comp. Phys.,  229,  4724-4761 (2010).
[2]	R. Loubere, P.H. Maire and M. Shashkov, “ReALE: A Reconnection-based Arbitrary Lagrangian-Eulerian Method in cylindrical geometry”, Computers & Fluids, In press (2010).  
","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l958m701uboeesgo91kugj6804","2010-12-20 18:50:44","2010-12-21 05:26:33"
"862","3","Total positivity on orientable surfaces","2011-01-28 14:00:00",NULL,"SAS 4201","Pavlo Pylyavskyy",,"University of Minnesota",,,"We develop a combinatorial model of networks on orientable surfaces, and study weight and homology generating functions of paths and cycles in these networks. Network transformations preserving these generating functions are investigated. We show that our model on a cylinder gives a decomposition and parametrization of the totally nonnegative part of the rational unipotent loop group of GL_n. This is joint work with Thomas Lam.","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/s4shp1ra96qh3v2u47esp855qk","2011-01-03 16:45:28","2011-01-16 13:07:09"
"863","21","2011 AMC Test at NCSU","2011-02-23 15:15:00",NULL,"SAS 1102",,,,,"http://www.math.ncsu.edu/selfreg/amc.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/136gjg4kctbf4dgr0eepjgn0l0","2011-01-09 17:46:56",NULL
"864","14","Spring 2011 Math Departmental Meeting","2011-01-11 16:00:00",NULL,"SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/m492cdtmj5ujm097kpada8hpl4","2011-01-10 12:06:48",NULL
"865","4","Self-organization and emergent patterns in dryland vegetation","2011-03-16 15:00:00",NULL,"SAS 4201","Sally Thompson","http://www.duke.edu/~set8/About.html","Nicholas School of the Environment, Duke University","Stephen Schecter",,"Remotely sensed information about the Earth's surface is more available than ever before, and at sufficiently fine resolution (<1m) that we can observe the scales on which plants interact with their landscape.  From a complex-systems perspective of the earth's surface, we can interpret the spatial distribution of vegetation as both a product of landscape processes (climatic, pedological, geomorphological, hydrological and ecological) and as a driver of ongoing landscape function.  That is, information about the way the landscape works should be reflected in the spatial distribution of vegetation.  Interpreting this information remains an outstanding and nontrivial challenge in the earth sciences.  However, under circumstances where (a) spatial patterns are readily observable, and (b) the links between pattern and process are sufficiently one-to-one, theoretical developments are closing in on the challenge of interpretation.  This seminar outlines recent progress in linking theoretical models of vegetation spatial pattern formation in drylands to observations and mechanistic descriptions of such patterns, with implications for understanding ecosystem resilience and desertification.

The seminar will conclude with a discussion of potentially interesting intersections of differential equations with problems that contemporary hydrologists are thinking about.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ulvrhu7h3q07er9t8gjqilatuo","2011-01-11 17:38:42","2011-03-13 12:58:18"
"866","12","Current challenges in pedestrian dynamics and crowd modeling","2011-02-14 16:00:00",NULL,"SAMSI, RTP, room 150","Pierre Degond",,"Université Paul Sabatier, France",,,"Understanding Pedestrian and crowd dynamics is an important issue
in modern societies. Recent crowd disasters (e.g. Duisburg love parade (July
2010) or Cambodia water festival (November 2010)) have put the safety issues
in the forward scene. Another important issue is the efficiency of public
arenas such as subway corridors, train or airport terminals, or shopping
malls. Many different kinds of models of pedestrian and crowd dynamics
exist, from the discrete (individual-based) ones to the continuum ones. The
talk will review the salient features of these models. However, most of the
existing models suffer from a poor validation against experimental data.
There are many difficulties ranging from ethical to technical ones which
explain why the data are scarce. We will report on a series of experiments
that have been conducted in the 'Pedigree' project in France and the
preliminary findings that have resulted from these data. Future modeling
directions and challenges will be discussed. ","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g1v166qgcg0inev0q79delcmdc","2011-01-13 14:09:09","2011-02-01 12:46:57"
"867","2","From Gene Trees to Species Trees","2011-01-24 15:00:00",NULL,"SAS 4201","Tandy Warnow","http://www.cs.utexas.edu/~tandy","Department of Computer Sciences, University of Texas at Austin","Michael Singer",,"Estimating the Tree of Life will likely involve a two-step procedure, where in the first step trees are estimated on many genes, and then the gene trees are combined into a tree on all the taxa. The computational problems involved here are substantial and interesting. Because the individual gene trees may not include all the species, even if all estimated gene trees are correctly computed, finding the true supertree is NP-hard. Furthermore, estimated gene trees may not be correct, making the estimation problem additionally challenging.  Finally, the true gene trees may not agree with each other or with the species tree, due to biological processes such as deep coalescence, or gene duplication and loss.  In this talk, I will present two recent algorithms that make advances on these problems.  The first algorithm (Swenson et al., Systematic Biology, accepted subject to revision) addresses the case where the true gene trees (but not the estimated gene trees) match the induced subtree within the true species tree. The second algorithm (Yun et al., RECOMB 2011, in press) addresses the case where the true gene trees are allowed to differ from the true species tree, due to deep coalescence (a population-level process). In each case, we prove structural theorems that explain why we obtain excellent results.  We also provide experimental evidence that SuperFine produces dramatically more accurate supertrees than any of the current supertree methods, and does so extremely quickly.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u19qqmju6chd0grukm7avu0l4g","2011-01-14 11:26:59","2011-01-19 09:50:35"
"868","21","Spring 2011 NC State Math Grad Student Recruitment","2011-02-25 08:00:00","2011-02-27 17:00:00","NC State Campus SAS Hall",,,,,"http://www.math.ncsu.edu/forms/gradrecruit/app/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b1atun4jngpdqg8bdilsvkdckc","2011-01-14 16:14:04",NULL
"869","6","Sparse Block Householder SVD","2011-02-01 15:00:00",NULL,"SAS 4201","Gary Howell","http://www.csc.ncsu.edu/directories/staff_info.php?id=2388","Computer Science, NCSU","NA Seminar",,"Determination of singular values of dense matrices typically uses scalably orthogonal Householder transformations.  For speed, initial reduction is to a banded matrix, accomplished by matrix matrix multiplications.   This talk applies the same method to determine singular values of sparse matrices.

For the sparse case, updates of the matrix are deferred (avoiding fill).  Numerical aspects of the problem are discussed. Some of the tricks used are
1) an initial dense random Householder transformation.
2) using 64 bit integers to allow large problem sizes.
3) tuning dense BLAS to work well for the case of long skinny matrices.

The most current work is on the computation of SVDs of relatively small O(1000) banded upper triangular matrices.  These are built up by the algorithm, with singular values compared as a convergence criterion.   At size around one thousand, repeated computation of the singular values takes a significant time.
","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6eegobjquiekjnh7mmqmahcj5g","2011-01-17 17:57:31","2011-01-26 15:04:37"
"870","3","Partitions and compositions:  A tale of two symmetries","2011-02-11 14:00:00",NULL,"SAS 4201","Sarah Mason",,"Wake Forest University",,,"This talk explores the role of partitions in symmetric function theory and their counterpart, compositions, in quasisymmetric function theory.  We look at properties that are common to both settings, ways in which they differ, and interactions between the two.  Along the way we develop several new bases and explain how these can be used to prove results in both settings.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lct45kmi4mpdvb51p50stjqs24","2011-01-20 12:00:18","2011-01-25 16:33:06"
"871","23","Feedback Regarding the Joint Mathematics Meetings","2011-01-28 15:00:00",NULL,"SAS 4201","Student Panel",,"North Carolina State University","Ralph Smith",,"The Joint Mathematics Meetings (JMM) provide an important opportunity to give presentations, attend talks, and interview with potential employers.  Before the break, we had an RTM that focused on preparation for the JMM.  In this RTM, a panel of attendees will discuss their experience and provide insights that will enhance the experience for students attending future JMM.  Additionally, you can hear harrowing tales about trying to return from New Orleans during a winter storm!

This RTM is recommended for all students planning to attend future JMM.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/net48ojcg8d95dhamvm1lffb3o","2011-01-24 12:10:22",NULL
"872","8","On the Computing Time of the Continued Fractions Method","2011-03-16 16:00:00",NULL,"SAS 4201","Werner Krandick",,"Drexel University","Hoon Hong",,"Algorithms for polynomial real root isolation are an important part of
computer algebra but few lower bounds are known for their maximum
computing time functions.  One exception is the continued fractions
method due to Vincent (1836) and recommended by Uspensky (1948).
Collins and Akritas (1976) proved that the maximum computing time of the
method is at least exponential in the length of the coefficients of the
input polynomial.  That lower bound motivated two algorithmic
innovations, the bisection method by Collins and Akritas (1976) and the
continued fractions method with root bounds (Akritas 1978, Sharma 2007).
 To this day no non-trivial lower bounds are known for the maximum
computing time functions of either one of those methods.  This talk
reports on joint work by Collins and Krandick that establishes such a
bound for the continued fractions method with root bounds through a
series of about eighty theorems and lemmas.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/br4bp64rc2ggrsr3a5kbbvklao","2011-01-24 16:47:15","2011-03-09 07:43:53"
"873","3","The Steinberg torus","2011-04-08 14:00:00",NULL,"SAS 4201","John Stembridge",,"University of Michigan",,,"The Steinberg torus is a cell complex naturally associated to any affine Weyl group W. Although less well known than the Coxeter complex, it deserves equal billing in the affine Coxeter world.  Steinberg used it to give a slick proof of Bott's formula for the Poincare series of W, and it is closely linked to the cohomology of the associated Coxeter fan. In this talk we will discuss these applications as well as some recent joint work with K. Petersen and K. Dilks on the combinatorics of affine descents.
","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fcj5433acrdat6tr0bjadn1um0","2011-01-25 14:33:50","2011-01-31 14:23:05"
"874","22","Why are there are only 17 Wallpaper Groups?","2011-01-26 16:00:00",NULL,"SAS 2102","Amassa Fauntleroy",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/012611.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c305530srr4dotj0djdve07k04","2011-01-25 16:23:12",NULL
"875","22","A Point Pattern Matching Problem: How a problem was actually solved - a day in the life of a mathematician","2011-02-02 16:00:00",NULL,"SAS 2102","John Peach",,"MIT Lincoln Laboratory",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/020211.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e1g79i3hlvagrcl5tapsh4hvnk","2011-01-25 16:24:42","2011-01-25 16:25:08"
"876","26","Stability of constrained capillary interfaces: contact-line dynamics and symmetry-breaking of the sessile drop","2011-01-31 16:00:00",NULL,"SAS 4201","J.B. Bostwick",,"NC State Mathematics Postdoc",,,"Capillary interfaces are ubiquitous in nature and have been studied extensively since the time of Young (1805) and Laplace (1806), who introduced the notion of surface tension. Early work on the subject was primarily focused on isolated surfaces (unconstrained), while more recently there has been an interest in partially-supported interfaces with an emphasis on the dynamics of the three-phase contact-line. With regards to terrestrial applications, most technologies that employ capillary interfaces are constrained and the classical results (unconstrained) can be of limited utility. To elucidate, this talk will focus on the linear stability of the sessile drop under a number of contact-line conditions, including a moving contact-line modeled by a continuous contact-angle against speed relationship. The integro-differential equation, governing the motion of the interface, is formulated as a functional equation using inverse operators, which are parameterized by azimuthal wave-number, volume via the static contact-angle (wetting) and the boundary conditions on the three-phase contact-line by a spreading parameter. Although the majority of motions are oscillatory, an instability is found that is related to `walking' or translational motion of the drop. As a limiting case, a hemispherical drop perturbed by a fixed contact-angle disturbance has characteristic oscillation frequencies, which are degenerate with respect to azimuthal wave-number much like the Bohr model of the atom is degenerate with respect to angular momentum quantum number. This degeneracy can be attributed to the configurational symmetry of the hemispherical base-state and is broken by smoothly varying either i) the volume or ii) the spreading condition. The analogy between the spectrum of these `broken' states and the filling order of the periodic table by energy levels both organizes and explains the hierarchy of frequencies.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oij43sh4fl95fq4haj4lm5ll44","2011-01-26 13:32:52",NULL
"877","21","Future Directions in Applied Mathematics Workshop","2011-03-10 08:00:00","2011-03-11 17:00:00","NC State Campus SAS Hall",,,,,"http://www.ncsu.edu/crsc/wfdam/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/q3nfm6afnr70g3lfdnnlpme6kc","2011-01-27 09:54:03",NULL
"878","28","AWM Lunch Seminar: Stress Management","2011-02-03 12:00:00",NULL,"SAS 4201","Dr. PJ Adams",,"NC State","AWM Student Chapter",,"AWM Student Chapter will be hosting a lunch seminar on Thursday, Feb. 3th  from 12 - 1 in SAS 4201.  Spring semester can be stressful time when dealing with the end of the year, whether you are trying to finish your thesis or just trying to figure out what classes to take in the Fall.   We will be discussing how to politely handle all of the stress that comes from being a TA while taking your own classes as well.  Dr. PJ Adams from the Counseling Center will be joining us to give us tips on how to deal with stress and how to address these problems.  He will also address dealing with stressed out students.  

All graduate and undergraduate math students are invited to attend.  Lunch will be provided.  ","klstagg","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/31lg8iacand88ld7fopioj0coo","2011-01-27 12:56:58",NULL
"879","4","Generic properties of scalar parabolic equations","2011-03-30 15:00:00",NULL,"SAS 2102","Genevieve Raugel","http://www.math.u-psud.fr/anm_edp/donnees/raugel.htm","Universite de Paris-Sud, Orsay","Steve Schecter",,"In this talk, I generalize the classical Kupka-Smale theorem to the case of scalar parabolic equations. More precisely, I show that, generically with respect to the nonlinearity, the semi-flow of a reaction-diffusion equation on a bounded domain in R^n or on the torus T^n has the Kupka-Smale property, that is, all the critical elements (i.e. the equilibrium points and periodic orbits) are hyperbolic and the stable and unstable manifolds of the critical elements intersect transversally. I will also consider the particular case of T^1. In this case, the semi-flow is generically Morse-Smale, that is, it has the Kupka-Smale property and, moreover, the non-wandering set is finite and is only composed of critical elements. One thus obtains a dense set of non-gradient reaction-diffusion equations on T^1 that have the Morse-Smale property and hence are structurally stable. (Joint work with P. Brunovsky and R. Joly).","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b4fpb3h5rbi44dv6ptolqknjno","2011-01-28 08:57:59","2011-03-28 15:06:26"
"880","3","N-point Virasoro algebras and their dense representations","2011-02-18 14:00:00",NULL,"SAS 4201","Ben Cox",,"College of Charleston",,,"In this talk we introduce and study N-point Virasoro algebras, which are natural generalizations of the classical Virasoro algebra and have as quotients multipoint genus zero Krichever-Novikov type algebras. We determine the necessary and sufficient conditions for the later two such Lie algebras to be isomorphic. Moreover we determine their automorphisms, their derivation algebras, their universal central extensions, and some other properties. We also construct a large class of modules which we call dense modules, and determine the necessary and sufficient conditions for them to be irreducible.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rjbm7spfiftm4cppo7bntapq9g","2011-01-28 14:01:32",NULL
"881","14","Departmental Tea and Cookies","2011-02-02 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ktm01ltck3vko6e0efnk68op2g","2011-01-31 10:55:40",NULL
"882","14","TA Grading Party","2011-02-04 17:00:00",NULL,"SAS 4104",,,,"TA Seminar",,"It's that time of year.  The first TA grading party of the semester will be on Friday in the Math Commons.  Bring your tests and we'll bring the food.  

Please pass this on to your undergraduate and non-math TA's as well.","klstagg","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/823ocpmcslrtnmoniltmut6f14","2011-01-31 12:33:51",NULL
"883","21","Climate change -the past, the present and our future","2011-02-15 19:00:00",NULL,"Bryan Center at Duke University, Von Canon Room","Douglas Nychka","http://www.image.ucar.edu/~nychka/","National Center for Atmospheric Research (NCAR)",,,"Dr. Douglas Nychka, Director of the Institute of Mathematics Applied to Geosciences for the National Center for Atmospheric Research (NCAR), will be speaking at the first Statistical and Applied Mathematical Sciences Institute (SAMSI) Public Lecture. His presentation is entitled: “Climate Change: the Past, the Present and Our Future.” Dr. Nychka will discuss how the reconstruction of past climate, including the “hockey stick curve,” is relevant to understanding the role of human influence on today's climate. This in turn leads to better understanding of the likely future changes in climate and their implications for our society.

The lecture is free and open to the public. The lecture is created specifically for an audience who is not in the mathematical or statistical field. This is the first in a new series of public lectures sponsored by SAMSI. The series will feature leading statisticians and applied mathematicians from around the world whose work reflects the SAMSI mission of using statistics and applied mathematics to address fundamental scientific problems. This lecture is sponsored by the Kenan Foundation.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qtb7e47la5nc7sfdig2mqdftdk","2011-02-02 09:08:37",NULL
"884","23","Post-Interview Topics","2011-02-04 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"You've had one or more job interviews and you may wonder what to do now.  For example, should you negotiate if you receive an offer?  Is it ever okay to accept more than one offer?  What do you do if you don't hear back from an interview?

These questions and others will be discussed during this week's RTM.  This session should be of interest to all students and postdocs presently looking for a job.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g4s138sbmfm123ka8dl34mocts","2011-02-03 10:50:33",NULL
"885","22","Rectangulations and Pattern-avoiding permutations","2011-02-09 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/020911.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5rk4rldnbvkeligpb4i1brplmo","2011-02-04 11:11:28",NULL
"886","22","Releasing your Inner Polynomial","2011-02-16 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/021611.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5m1i80qoapp5o49nhhjr8cree0","2011-02-04 11:12:26","2011-02-14 08:44:42"
"888","22",,"2011-03-02 16:00:00",NULL,"SAS 2102","Hoda Bidkhori",,"NC State",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p9qkeuo0dr5eqc9ea4gc831epc","2011-02-04 11:13:47",NULL
"890","22","Mathematics and Biology","2011-03-23 16:00:00",NULL,"SAS 2102","Hien Tran",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/032311.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gjpdpak64c5hkv1cq1pd8c3tkk","2011-02-04 11:14:40","2011-03-23 10:17:06"
"891","22","Mathematics of Materials","2011-03-30 16:00:00",NULL,"SAS 2102","Ralph Smith",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/033011.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o6v1182vn3p8fh910uj8gkucu0","2011-02-04 11:15:12","2011-03-28 16:01:54"
"892","22","Efficient Algorithms for Digital Halftoning","2011-04-06 16:00:00",NULL,"SAS 2102","John Harlim",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/040611.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4jd9ck132303rgutoc6uos1i6s","2011-02-04 11:15:51","2011-03-31 08:54:40"
"893","22","How to Model and Simulate Moving Fronts","2011-04-13 16:00:00",NULL,"SAS 2102","Zhilin Li",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2011/041311.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/182f9bepkhq4m1t4tgi31fh60g","2011-02-04 11:16:36","2011-04-08 08:39:50"
"895","14","Departmental Tea and Cookies","2011-02-09 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dl5evehauothfsu360muk1hvt0","2011-02-08 09:54:13","2011-02-08 10:11:34"
"896","26","Model and Simulation of Red Blood Cell Dynamics in Patients with Chronic Kidney Disease","2011-02-14 16:00:00",NULL,"SAS 4201","Karen Bliss",,"NC State Mathematics Graduate Student",,,"Kidneys are the main site of production of the hormone erythropoietin (EPO) that is the major regulator of erythropoiesis, or red blood cell production. EPO level is normally controlled by a negative feedback mechanism in the kidneys, but patients with chronic kidney disease (CKD) do not produce sufficient levels of EPO to maintain appropriate blood hemoglobin concentration. A mathematical model, including interactions with iron and inflammation, is developed for erythropoiesis in patients with CKD. Methods of numerical solution and validation of numerical methods are discussed. Simulation results under varying conditions and treatment protocols are presented.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ernaks0432plmmgt60cek5214s","2011-02-11 10:16:29",NULL
"897","14","Departmental Tea and Cookies","2011-02-17 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/r6u5u2id6jq5d8qcp0f3r1crj0","2011-02-11 10:39:10",NULL
"898","14","Hubert V. Park Classroom Dedication","2011-03-01 15:00:00",NULL,"SAS 2102",,,,,,"Your reply is requested by February 23, 2011
919-515-1678 or donor_relations@ncsu.edu","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u91nc3k7dsq2qgm7b12o27gbp0","2011-02-17 12:07:45",NULL
"899","26","Persistence Barcodes for Digits","2011-02-21 16:00:00",NULL,"SAS 4201","Mandy Smith",,"NC State Mathematics Graduate Student",,,"This research is focused on the problem of finding a faster algorithm for computer recognition of electronically scanned digits. The method used involves expanding the image to the third dimension by adding the dimension of tangent angles. Betti numbers representing the number of segments and the number of wholes per digit are collected. We then calculate a barcode to document the “lifespan” of each component. By comparing the distance between barcodes, a distance matrix can be created to sort the digits. We conduct tests using real handwriting samples from the MNIST database. The goal is to create a learning algorithm for the computer.

","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/adt138ef2nf09ifu4bqbtcg2bs","2011-02-18 09:06:07",NULL
"900","7","A Stochastic Portfolio Optimization Model with Bounded Memory","2011-03-14 15:00:00",NULL,"SAS 4201","Tao Pang","http://www4.ncsu.edu/~tpang/","NC State, Mathematics","Min Kang",,"We consider a portfolio management problem of Merton's type in
which the risky asset return is related to the return history. The problem
is modeled by a stochastic system with delay. The investor's goal is to
choose the investment control as well as the consumption control to
maximize his total expected, discounted utility. Under certain situations,
we derive the explicit solutions in a finite dimensional space and the
verification results are obtained. Moreover, we will consider stochastic
models with delays in more general form.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ie5kqvurmvhr7283s8l1gs7vsk","2011-02-18 15:53:42","2011-03-12 17:40:22"
"901","7","Disordered Asymmetric Exclusion Process in Non-equilibrium","2011-04-04 15:00:00",NULL,"SAS 4201","Min Kang","http://www4.ncsu.edu/~mkang2/","NC State, Mathematics","Min Kang",,"We consider a simple traffic model, namely, a totally asymmetric simple exclusion process with a quenched disorder.  Particles are moving in one direction with one-particle-per-site rule where disorder is introduced in the system via random waiting times between successive jumps.  At low densities, there are no equilibrium distributions, and all the analysis is done in non-equilibrium.  The results provide the behavior of the tagged particle's location for a large time scale and the order of fluctuation distribution.  In plain terms, this disordered traffic system will exhibit formation of large growing platoons behind slow particles at a low density (non-equilibrium) and gives a full understanding on the slow-down experienced by the particle.  ","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4vvgurpv6dlo7i4d29p3r073c0","2011-02-18 15:55:48","2011-03-21 14:03:03"
"902","7","Estimating Population Eigenvalues From Large Dimensional Sample Covariance Matrices","2011-04-18 15:00:00",NULL,"SAS 4201","Jack Silverstein","http://www4.ncsu.edu/~jack/","NC State, Mathematics","Min Kang",,"Let B_{n} = (1/N) T_{n}^{1/2} X_{n} X_{n}^{*} T_{n}^{1/2} where X_{n} = (X_{ij}) is n by N with i.i.d. complex standardized entries, and T_{n}^{1/2} is a Hermitian square root of the nonnegative definite Hermitian matrix T_{n}. This matrix can be viewed as the sample covariance matrix of N i.i.d. samples of the n dimensional random vector T_{n}^{1/2}(X_{n})_{. 1}, the latter having T_{n} for its population covariance matrix. Quite a bit is known about the behavior of the eigenvalues of B_{n} when n and N are large but on the same order of magnitude. These results are relevant in situations in multivariate analysis where the vector dimension is large, but the number of samples needed to adequately approximate the population matrix (as prescribed in standard statistical procedures) cannot be attained. Work has been done in estimating the eigenvalues of Tn from those of Bn. This talk will introduce a method devised by X. Mestre, and will present an extension of his method to another ensemble of random matrices important in wireless communications.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sk1hs19cvje1qk1668eheq9ql8","2011-02-18 15:57:35","2011-04-15 18:46:53"
"903","6","Affine invariant methods for search and sampling","2011-04-05 15:00:00",NULL,"SAS 4201","Jonathan Goodman","http://www.math.nyu.edu/faculty/goodman/","NYU Courant Institute","NA Seminar",,"Searching and sampling are two problems that depend on a function of n variables.
Searching means finding extreme points.  Sampling means generating Monte Carlo samples
from a given multivariate probability density.  Typical applications have variables with different
units or scalings, which can make contours of the function seem highly stretched.  it is common
to rescale poorly scaled problems to make contours ""rounder"".  The talk discusses algorithms
that are affine invariant.  This means that its behavior is unaffected (in exact arithmetic) by 
affine reparametrization.  Two well known affine invariant methods for searching are the
Nelder Mead derivative free method and the Gauss-Newton method for nonlinear least squares.
We present two affine invariant methods for Monte Carlo sampling.  One is an ensemble
method that samples along lines determined by two existing samples.  The other is a Monte
Carlo version of Gauss Newton.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1s5ipb2a7ad8gv35946ndo5nbc","2011-02-20 13:47:23","2011-03-28 07:32:28"
"904","24","MGSA Cookie Contest","2011-02-21 11:00:00",NULL,"SAS 4104",,,,,,"Just a reminder to stop by the commons today between 11 and 2 for the cookie contest. I hope to see you all there!

(Also, if you would like to drop your dessert entry in my office -SAS 4125- before 11 you may do so)
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s2aoerthiabku8skop353m2ov4","2011-02-21 10:19:22",NULL
"905","15","Life and Research at Northrop Grumman, lunch provided","2011-02-24 12:00:00",NULL,"SAS 4201","Anjela Govan",,"Northrop Grumman, NCSU Math alum","SIAM Student Chapter",,,"klrehm","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8qf6eb5kvdbf3f0onr17ti8muc","2011-02-21 15:44:34",NULL
"906","14","Departmental Tea and Cookies","2011-02-23 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/l9k6jhug7qvqhlg84lr60mp6eo","2011-02-22 10:52:59",NULL
"907","6","Meeting Sustainability Constraints for Berry Farming in the Pajaro Valley","2011-03-15 15:00:00",NULL,"SAS 4201","Kathleen Fowler","http://www.clarkson.edu/math/faculty_pages/fowler.html","Clarkson","NA Seminar",,"The Pajaro Valley, located on the Pacific Coast of Central California, is known for berry farming, a very water intensive industry.  The berry industry is now in jeopardy, as the valley's aquifer is overdrawn, causing seawater intrusion which threatens to destroy freshwater resources.  To combat this, Driscoll's Berries, the company that distributes most of the berries in the valley, is actively seeking a way to reduce the aquifer draw by analyzing alternative farming techniques.  This will be accomplished by creating a mathematical farm model and optimization strategy to design farming approaches that meet a sustainable water yield constraint.  Furthermore, we consider surface water analysis as a means to supplement the aquifer. These results were produced at a focused, collaborative sustainability workshop at the American Institute of Mathematics.
","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2uapvcp2j0h1l6e00f7kluc4po","2011-02-22 13:29:57","2011-03-11 10:19:21"
"909","26","Adaptive Control Design for Hysteretic Smart Systems","2011-02-28 16:00:00",NULL,"SAS 4201","Jerry McMahan",,"NC State Mathematics Graduate Student",,,"Ferroelectric and ferromagnetic actuators are being considered for a range of industrial, aerospace, aeronautic and biomedical applications due to their unique transduction capabilities. However, they also exhibit hysteretic and nonlinear behavior that must be accommodated in models and control designs. If uncompensated, these effects can yield reduced system performance and, in the worst case, can produce unpredictable behavior of the control system. In this presentation, we address the development of adaptive control designs for hysteretic systems. The resulting algorithms permit the adaptive estimation of certain model parameters as well as control gains for vibration attenuation or tracking. Properties of the control design are illustrated through numerical examples.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cn74duaasm54h36ir5vbvdag38","2011-02-28 07:58:47",NULL
"911","3","Generic rectangulations and pattern-avoiding permutations","2011-04-01 14:00:00",NULL,"SAS 4201","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,,"A rectangulation is a tiling of a rectangle by rectangles. The rectangulation is called generic if no four of its rectangles share a corner.  We consider generic rectangulations (with n rectangles) up to combinatorial equivalence.  It turns out that generic rectangulations are in bijection with permutations that avoid a certain set of patterns.

I'll give background information on rectangulations and pattern avoidance. Then I'll make the connection between generic rectangulations and pattern-avoiding permutations, drawing on earlier work with Shirley Law on ""diagonal"" rectangulations and draws on the lattice theory of the weak order on permutations.
","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/evj89phfsjed0fh6m98uk9clbo","2011-02-28 17:51:38","2011-03-29 13:25:50"
"912","3","Lattice point methods for combinatorial games","2011-04-29 14:00:00",NULL,"SAS 4201","Alan Guo",,"Duke University",,,"We encode arbitrary finite impartial combinatorial games in terms of lattice points in rational convex polyhedra. Encodings provided by these lattice games can be made particularly efficient for octal games, which we generalize to squarefree games. These encompass all heap games in a natural setting where the Sprague-Grundy theorem for normal play manifests itself geometrically. We provide polynomial time algorithms for computing strategies for lattice games provided that they have a certain algebraic structure, called an affine stratification.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/48hcekk7as24n500v52rjk8cj8","2011-02-28 17:53:22","2011-04-26 14:17:28"
"913","14","Departmental Tea and Cookies","2011-03-02 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/887mhk6p14bsv93b5he3euu378","2011-03-01 10:34:25","2011-03-01 10:34:55"
"914","4","Strichartz estimates for the Schrodinger and Wave Equations on polygonal domains","2011-04-13 15:00:00",NULL,"SAS 4201","Jeremy Marzuola","http://www.unc.edu/~marzuola","University of North Carolina at Chapel Hill","Mark Hoefer",,"With Matt Blair, G. Austin Ford, and Sebastian Herr, we establish linear, space-time dispersive estimates on compact manifolds with corners. Specifically, we study the boundedness of solutions to the Schrodinger and Wave Equations on polygonal planar domains. The result relies heavily on treating the domain as a Euclidean surface with conic singularities, and on the works of Burq-Gerard-Tzvetkov on smooth, compact Riemannian manifolds. Given time, we will also discuss some motivation and applications.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tq9kb1g4gpoplpnou14i0chv18","2011-03-02 15:31:43","2011-04-08 10:36:09"
"915","8","Decompositions of commutative monoid congruences and binomial ideals","2011-04-13 16:00:00",NULL,"SAS 4201","Thomas Kahle",,"Mittag-Leffler Institute","Seth Sullivan",,"Each binomial ideal in a monoid algebra defines a congruence
on the monoid and decompositions of the congruence correspond to
decompositions of the binomial ideal.  Primary decompositions of
binomial ideals into binomial ideals exist only over algebraically
closed fields and their nature depends on the characteristic of the
field.  Working solely with the congruence of a given binomial ideal, we
are able to define and systematically develop decompositions that are
completely independent of the field but still capture all essential
features of the ideal.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0dgjc37859ee0eg26jfd59h454","2011-03-03 08:08:02","2011-03-09 07:45:03"
"916","26","Behavior Change in Problem Drinkers: Static Methods","2011-03-14 16:00:00",NULL,"SAS 4201","Keri Rehm",,"NC State Mathematics Graduate Student",,,"There is a wealth of qualitative knowledge on alcohol dependence, and with recent improvements in data collection techniques and efficiency, there is also a vast amount of detailed patient information – down to a timescale of days - in clinical trials for alcohol dependence treatments. Common approaches to analyzing data in non-quantitative fields involve static techniques that are unable to describe relationships that change over time. Regression analysis and principal component analysis are two techniques representative of the static methods commonly used and can be highly effective in describing some data sets. We examine how well these techniques perform when applied to the data of problem drinkers measured on a daily basis and discuss how these results lead us to believe that dynamic models would better explain patterns in this data. This is joint work with Dr. H. T. Banks and Dr. Karyn L. Sutton at North Carolina State University, and with Dr. Jon Morgenstern, Dr. Alexis Kuerbis, Lisa Hail, and Christine Davis at Columbia University.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9c4kpl8e449m4fg22qjo1k20so","2011-03-03 11:14:40",NULL
"917","3","Inversion Sequences, Eulerian Polynomials, and Lecture Hall Partitions","2011-03-18 14:00:00",NULL,"SAS 4201","Carla D. Savage","http://www4.ncsu.edu/~savage/","NC State",,,"We introduce ""s-inversion sequences"" and their statistics and prove a general theorem relating the distribution of these statistics to the enumeration of ""s-lecture hall partitions"".  In the process, we integrate and extend previous results on lecture hall partitions, we re-interpret and generalize the Eulerian polynomials, and we establish a connection between the partition theory of lecture hall partitions and their geometry.  This includes joint work with Michael Schuster, Gopal Viswanathan, and Thomas Pensyl.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lvr8047fi1r8gret0g53hsgnf8","2011-03-14 08:10:10",NULL
"918","14","Departmental Tea and Cookies","2011-03-17 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/agksfum5csrf3bv5d2uriol8g0","2011-03-14 15:42:45",NULL
"919","21","NSF-CBMS Conference on Deformation Theory of Algebras and Modules","2011-05-16 08:00:00","2011-05-20 13:00:00","SAS Hall","Martin Markl",,"Institute of Mathematics of the Czech Republic Academy of Sciences",,"http://www4.ncsu.edu/~lada/CBMS/cbms.htm",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5prvk2q3s8gdsd6jid15q1vu28","2011-03-15 14:20:54",NULL
"920","14","Awards Day","2011-04-27 16:00:00",NULL,"SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/51vvusrs9nqtgennqvrcp68c4k","2011-03-16 10:06:28",NULL
"921","26","Observers for Systems of Differential Algebraic Equations: The Linear Time-Invariant Case","2011-03-21 16:00:00",NULL,"SAS 4201","Karen Bobinyec",,"NC State Mathematics Graduate Student",,,"Systems of differential algebraic equations (DAEs) describe many physical systems of interest in control theory. Constructing observers for systems of DAEs is an active area of control theory research because a general design method is not currently accepted. Our approach for constructing observers combines recent results from numerically computed completions of DAE systems with observers designed for systems of ordinary differential equations. Results for full- and reduced-order observers in the linear time-invariant case are presented.","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7a4kpq1kt6v7akpcq30pdv1m84","2011-03-17 14:50:24",NULL
"922","14","Departmental Tea and Cookies","2011-03-25 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0h3174d17kd4tu042dkv5joc5k","2011-03-21 10:20:06",NULL
"923","19","Generalizations and Analogs of the Frattini Subalgebra","2011-03-21 15:30:00",NULL,"SAS 2225","Kristen Stagg","http://www4.ncsu.edu/~klstagg/index.shtml","NC State",,,"Giovanni Frattini introduced his subgroup, now called the Frattini subgroup, in the nineteenth century. It has inspired investigations since it appeared. Beside being studied in it's own right, it has been generalized in group theory, transformed into what is the Jacobson radical in ring theory and copied in Lie and other algebras. In the present work, we make further contributions to the theory of the Frattini subalgebra and introduce Lie algebra generalizations, which have group theory counterparts.","edbancro","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fr4e63i8h0rd472hbofp3egiho","2011-03-21 11:00:31",NULL
"924","3","Tree Space and Its Use in Comparing and Performing Statistics on Trees","2011-03-30 16:00:00",NULL,"SAS 1102","Scott Provan","http://www.unc.edu/~provan/","UNC Chapel Hill",,,"Trees provide a valuable way of organizing and describing data, and arise in a wide range of applications.  Comparing and determining statistical properties of trees, particularly where edge weights are present, is an important problem when studying groups of trees describing the same system.

This talk will discuss a framework for analyzing weighted trees that uses a special ""tree space"" developed by Billera, Holmes, and Vogtmann.  We will give a polynomial-time algorithm for finding geodesics between trees in this space, discuss properties of this space and its geodesics, and show the usefulness of this space in  finding ""average"" trees and performing statistical analysis on trees.

We will discuss two interesting applications of the research, one in the comparison of phylogenetic trees in biology, and one in comparing the structure of arteries in a study of blood flow in the human brain.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0q6vrjjte276m7ugvqboujgkj4","2011-03-24 15:16:17","2011-03-24 15:17:35"
"925","24","Grading Party","2011-03-28 17:30:00",NULL,"SAS 4104",,,,,,"There will be a grading party in the Math Commons on Monday March 28 at 5:30PM.  Dinner will be sloppy joes, some sort of side, and dessert.  As always, please let me know if you are planning to attend so that we have a general idea how much food to buy. 

Susan Crook
susancrook@gmail.com","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ansudr6scri03otvt30r8q8hqg","2011-03-24 22:20:41",NULL
"926","26","Autoregressive Model for Real-Time Weather Prediction and Detecting Climate Sensitivity","2011-03-28 16:00:00",NULL,"SAS 4201","Emily Kang",,"SAMSI Postdoc",,,"Various recipes based on reduced stochastic models have been introduced for filtering as well as for climate modeling;  one of them is the Mean Stochastic Model (MSM) that replaces nonlinear terms with a diagonal Ornstein-Uhlenbeck process in Fourier space. Despite model errors introduced by such replacement, the MSM shows very encouraging results, especially when the hidden signal of interest is strongly chaotic. In this talk, I will present a generalization of the MSM with a diagonal autoregressive linear stochastic model in Fourier space as a filter model. Here, not only the filter model becomes computationally less expensive relative to the perfect model, but the associated Kalman filter on each Fourier mode is computationally as cheap as inverting a scalar. Using the Lorenz 96 (L-96) model as a test bed, we show that the non-Markovian nature of this autoregressive model is an important feature that captures the statistical nature of the hidden signal and produces accurate filtered solutions. Specifically, we show in numerical experiments that the filtering strategy based on the autoregressive linear stochastic model (called the AR(p) filter in this paper) produces much more accurate filtered solutions than the MSM in weakly chaotic regime. In strongly chaotic regime the performance of the AR(p) filter is still better or  at least comparable to that of the MSM. Furthermore, we find that this reduced filtering strategy is not as sensitive as standard ensemble filtering strategies to additional intrinsic model errors that often encountered when the model parameters are incorrectly specified. The potential of application of this autoregressive model to study climate sensitivity will also be discussed.

(Joint work with John Harlim)","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2ql2lkpef73i5akk5jh5i3k4c4","2011-03-25 11:01:22","2011-03-28 10:30:15"
"927","14","Departmental Tea and Cookies","2011-03-30 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kkb9hik7p1ga4doibqfqt6tdt0","2011-03-28 14:02:40",NULL
"929","19","Codes and Shifted Codes of Partitions","2011-04-04 15:30:00",NULL,"SAS 2225","J.T. Hird",,"NC State Mathematics Graduate Student",,,"The Bernstein operators are a special set of vertex operators that can generate the Schur functions. We demonstrate several combinatorial proofs of the action of the Bernstein operators on Schur functions. We then show the analogous results and combinatorial objects for Schur Q-functions.","edbancro","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2852nm43bb160557mgei9an3pc","2011-03-31 13:04:10",NULL
"930","14","Awards Day Reception","2011-04-27 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/js6on4m6bson42dg2l5rqi4t3g","2011-04-01 11:07:42",NULL
"931","26","Faraday Waves on Surfactant Covered Thin Films","2011-04-04 16:00:00",NULL,"SAS 4201","Lake Bookman",,"NC State Mathematics Graduate Student",,,,"krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qhq65pqbo1o9uj132p2nfb4g00","2011-04-01 12:03:57",NULL
"932","14","Departmental Tea and Cookies","2011-04-05 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/459bjcrbssakgmnbnka717ates","2011-04-04 12:11:33",NULL
"933","26","Synthesis of Second Generation Biofuels","2011-04-11 16:00:00",NULL,"SAS 4201","Lucus Van Blaircum",,"NC State Mathematics Graduate Student",,,,"krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1b18o7phqike9dsktv0ia4vhcc","2011-04-07 13:46:57",NULL
"934","14","Departmental Tea and Cookies","2011-04-12 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b7pejcc5fcggifr8l8b1mtvgk8","2011-04-11 10:35:18","2011-04-11 11:16:25"
"936","26","Wrinkling and Deflection Control of Corner Supported Membranes","2011-04-18 16:00:00",NULL,"SAS 4201","Jason Scott",,"NC State Mathematics Graduate Student",,,,"krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/05hu4vejjhq69b84dp8kkg76cg","2011-04-14 15:05:16",NULL
"937","26","Dispersive Shock Waves in Magma Flow","2011-04-18 16:30:00",NULL,"SAS 4201","Donovan Shickley",,"NC State Mathematics Graduate Student",,,,"krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mspqg0l6ap3fhr5a4l9snuqmhc","2011-04-14 15:05:52","2011-04-18 08:41:45"
"938","14","Departmental Tea and Cookies","2011-04-20 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bdulk8t10jg1r2ukf9uqm5u5l0","2011-04-14 15:28:20",NULL
"939","28","AWM Student Chapter Meeting","2011-04-20 11:15:00",NULL,"SAS 4201",,,,"AWM Student Chapter",,"The year is coming to an end and we will have one last meeting this semester where we will discuss some exciting news and elect new officers. 

If you are interested in being an officer for next year or would like to nominate someone, please email one of the current officers with the name of the person you are nominating and the position.

See you there!","klstagg","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/519j40e34fkl7n1ai5bmkjpij8","2011-04-17 19:54:04",NULL
"940","14","Undergraduate Honor's Research Project Presentation Day","2011-04-20 15:30:00",NULL,"SAS 2102","Kaysuv Boyina, Mark Jayne, and Becky Maus",,,,,"1. Kaysuv Boyina (3:30 - 3:50 pm)

Title : Modeling Surface Acoustic Wave Dispersion Using Various Methods.
Abstract : In this talk, we will discuss various methods of finding the phase velocity as a function of the frequency(Dispersion) in surface acoustic waves(SAWs).  We will speak about the advantages and disadvantages of each method.  We will also demonstrate the use of various models in order to determine the Surface Acoustic Wave Dispersion of different thin films on various substrates.  The main methods that we will be discussing is method involving Green's Functions and a method using integrals.

 2. Mark Jayne (3:50 - 4:10 pm)

Title : Evolution and Bak-Sneppen Fitness Models
Abstract : Does biological evolution take place at a slow and steady rate, or does it happen in quick, intense bursts?  Is the total collection of species moving to some optimal level of fitness, or is there in fact a large amount of randomness involved in extinction?  Much evidence has been gathered implying that the latter is true.  I will present three models, one for the case where the species are moving toward an optimal level of fitness, and two for the case which take the randomness into account.  I will also prove that the first model reaches the optimal level of fitness in the time limit, for any number of species greater one.  Later I will describe a Markov chain on one of the other models that leads to the proof of a limiting distribution of fitness.
 
 3. Becky Maust (4:10 - 4:30 pm)

Title : Representations of sl2 Lie Algebras
Abstract : When we add a Lie bracket to a vector space to give us the structure of a Lie Algebra, we add so much rich complexity to our space.  While this can add new insights, it also presents the challenge of how to study and understand this new structure.  Representation Theory is one powerful tool that can help us with this challenge.  Fortunately, the representations of a specific type of Lie Algebras, called semisimple Lie Algebras, are fairly straightforward in nature.  In my talk, I will introduce the concept of a Lie Algebra then focus of one specific Lie Algebra, sl2.  I will then work through the structure of a representation of sl2 and briefly describe how this is a model for representations of other semisimple Lie Algebras.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lk3s4163k2pru9erag7jpbn4tk","2011-04-19 10:12:22",NULL
"941","14","Grading Party","2011-04-20 17:30:00",NULL,"SAS 4104",,,,,,"Professors, Instructors, and Grad Students, please forward this on your undergrad/non math graders and TAs. Thanks!

There will be a grading party in the Math Commons on Wednesday, April 20 at 5:30PM.  Dinner will be pizza, soda, and dessert.  As always, please let me know if you are planning to attend so that we have a general idea how much food to buy.  

klstagg@ncsu.edu","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ktbj19mk81d1cshn9nquvevj0k","2011-04-19 16:14:35",NULL
"942","26","Two Phase Flow in Porous Media:  Traveling Waves and Stability","2011-04-25 16:00:00",NULL,"SAS 4201","Kim Spayd",,"NC State Mathematics Graduate Student",,,"Porous media flow is discussed in the context of secondary oil recovery by water drive.  A two dimensional partial differential equation model for two phase flow is presented.  In one dimension, the Buckley-Leverett equation is modified by including a dependence of capillary pressure on the rate of change of saturation. This model, due to Gray and Hassanizadeh, results in a nonlinear PDE that supports traveling waves corresponding to undercompressive shocks.  Further, the Saffman-Taylor instability for porous media is presented and generalized.  The resulting stability criterion, as it applies to Lax shocks, is interpreted and confirmed with numerical simulations.
","krspayd2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k0kqspimvem1qn9nb396pncj5o","2011-04-20 15:23:58","2011-04-23 20:22:38"
"943","19","Schur Mutlipliers of Nilpotent Lie Algebras","2011-04-25 15:30:00",NULL,"SAS 2225","Lindsey Bosko","http://www4.ncsu.edu/~lrbosko/","NC State Mathematics Graduate Student",,,"The Lie algebra analogue to the Schur multiplier has been investigated in a number of recent articles.  We consider the multipliers of Lie algebras of maximal class, classifying these algebras with a certain additional property.  The classification leads to results about a bound on the dimension of the multiplier for each of these algebras and also for p-groups of maximal class.  Additionally, it is known that a p-group with trivial multiplier has severe restrictions placed on it.  We show that a nilpotent Lie algebra with dimension greater than one will have a non-trivial multiplier.","edbancro","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h31s2p79q7bubo2q1vovfkg4v8","2011-04-24 15:09:01",NULL
"944","24","MGSA Tea","2011-05-06 11:00:00",NULL,"SAS 4104",,,,,,"MGSA will be having a tea this Friday from 11am-1pm in SAS 4104 (the lounge). We will be providing some snacks (veggies, cookies, etc) along with some hot beverages. 

We will also be holding elections at 11:45 for new officers for next year. If you are interested in running for any of the positions, which include President, VP, Secretary, Treasurer, or if you have any questions feel free to contact myself or any of the other three reps: Alyssa- amarmstr@ncsu.edu, Donovan- cdshickl@ncsu.edu, Jason -jrscott@ncsu.edu. You can also refer to our constitution if you would like more details about the roles of each officer MGSA Constitution. 

Thanks and I hope to see you all on Friday! 

Colleen McCarthy
MGSA Secretary","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vjdkr55ui0qgdf5m6sculb986c","2011-05-04 11:57:42",NULL
"945","14","Mathematics Graduation Ceremony","2011-05-13 15:00:00",NULL,"SAS 2203",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/m6uv1m3qejb03f70s9jhgqra2c","2011-05-10 11:03:10",NULL
"947","21","Thin Fluids Day 2011","2011-06-09 09:00:00","2011-06-09 17:00:00","SAS 1102",,,,,"http://nile.physics.ncsu.edu/cgi-bin/webpage/News/50_thinfluids.html","Karen Daniels and Michael Shearer (organizers)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/60uu9ett61suuu7drsntn5u9pg","2011-06-03 16:35:28",NULL
"948","1","Kinematics and numerical algebraic geometry","2011-10-10 15:00:00",NULL,"SAS 1102","Charles Wampler","http://www.nd.edu/~cwample1","General Motors Research and Development Center","Ilse Ipsen",,"Kinematics underlies applications ranging from the design and control of mechanical devices, especially robots, to the biomechanical modeling of human motion. The majority of kinematic problems can be formulated as a system of polynomial equations to be solved and so fall within the domain of algebraic geometry. While symbolic methods from computer algebra have a role to play, numerical methods that make strong use of algebraic-geometric properties, offer advantages in efficiency and parallelizability. Although these methods, built on polynomial continuation and collectively called Numerical Algebraic Geometry, are applicable wherever polynomials arise, e.g., chemistry, biology, statistics, and economics, this talk will concentrate on applications in mechanical engineering. A brief review the main algorithms of the field will indicate their broad applicability. We will also touch on a new development, isosingular theory, which promises to be useful in both numerical and symbolic settings for dealing with nonreduced and nonsmooth algebraic sets.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/ofv8jhvsc6bb0ru0f570ko5njk","2011-06-25 15:30:52","2011-09-23 11:56:10"
"949","8","Computational approach to the center-focus and integrability problem in R^3","2011-09-14 16:00:00",NULL,"SAS 4201","Adam Mahdi",,"University of North Carolina at Charlotte",,,"The center-focus problem is one of the long standing unsolved problems in the qualitative theory of planar polynomial vector fields. It asks to distinguish between a center (neighborhood is composed entirely of periodic orbits) and a focus (""spiralling orbits"") for a singularity having purely imaginary eigenvalues. During the talk we will consider a natural extension of the center-focus problem to systems in R^3 and present a symbolic computational approach to tackle it. In particular, we show that the set of systems having a center on the local center manifold corresponds to a variety in the space of admissible coefficients. We shall also discuss some computational challenges that arise for particular cases and state a number of open problems related to the subject. The topic is an example of an interplay between symbolic computation, integrability and qualitative analysis of ODEs.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2ve9i60e2qqsrfct0r5obqvbho","2011-07-22 14:50:54","2011-09-06 15:51:14"
"950","8","The entropic discriminant","2011-11-09 16:00:00",NULL,"SAS 4201","Cynthia Vinzant","http://www-personal.umich.edu/~vinzant/","University of Michigan",,,"The entropic discriminant is a non-negative polynomial associated to a matrix. It arises in contexts ranging from statistics and linear programming to singularity theory and algebraic geometry.   I'll discuss the geometry of this discriminant and its connection to matroids and hyperplane arrangements. We will also go over some nice special cases, like the discriminant of the univariate derivative and of the characteristic polynomial of a symmetric matrix.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1acgf5giih4mijlaosp8dscbsk","2011-07-25 09:32:34","2011-10-26 11:40:52"
"951","8","Algebraic aspects of conditional independence","2011-10-11 16:00:00",NULL,"SAS 4201","Johannes Rauh",,"Max Planck Institute, Leipzig",,,"Independence is an important statistical concept.  From a theoretical point of view independence is the easiest
assumption that allows to make general statements about large numbers of random variables, as they appear in limit
theorems, large deviations and asymptotic statistics.  On the other hand, it is the task of a statistician to find out whether random variables are independent of each other, or conditionally independent, or how they depend on each other.  This idea leads to the theory of graphical models.

Conditional independence (CI) statements can be formulated as algebraic equations, and reasoning with CI statements can
be done by analyzing the corresponding CI ideals.  Natural algebraic questions are to decide radicality or regularity of these CI ideals.  A primary decomposition of the CI ideal is useful to characterize the set of probability distributions that satisfy the corresponding CI statements.
In my talk I plan to give an overview over the topic, including the CI axioms and recent radicality results for a class of CI ideals related to the study of robustness.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j96bp07frgdjsiaoo7o9m01qao","2011-07-26 14:44:13","2011-10-10 16:29:48"
"952","6","Optimization in Financial Market Models","2011-08-19 15:00:00",NULL,"SAS 4201","Ekkehard Sachs",,"U Trier, Germany","Tim Kelley",,"Numerical methods in optimization play an increasingly important role in the application of mathematical models in financial markets. We review some of the models in option pricing together with their numerical solution. Then we consider more complex options, like barrier options, and formulate the composition of the corresponding hedge portfolio as an optimization problem. Issues of robustness of the parameters obtained will be addressed next. The last part of the talk is devoted to the numerical solution of a calibration problem for option pricing models which can be formulated using stochastic differential equations or partial differential equations. We discuss several issues as well as the advantages and disadvantages in the numerical treatment for these models.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u7f6mh534dh6u5av822p93lkoc","2011-07-28 21:08:38","2011-08-01 19:18:03"
"953","21","Undergraduate Research Summer Symposium","2011-08-03 13:00:00","2011-08-03 16:00:00","McKimmon Center at NC State",,,,,"http://www.ncsu.edu/ugrs/","The annual Undergraduate Research Summer Symposium will be held on Wednesday from 1pm until 4pm in the McKimmon Center.  I encourage you to attend to support the department's REU students who will be displaying their final posters. You can find more info about the Symposium as well as abstracts for all posters here:

http://www.ncsu.edu/ugrs/
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3khkrj2frhqah8mfgl7sd9ert8","2011-08-03 11:46:34",NULL
"955","3","Symmetric chain decomposition for cyclic quotients of Boolean algebras and relation to cyclic crystals","2011-08-26 16:00:00",NULL,"SAS 4201","Patricia Hersh",,"NC State",,,"The quotient of a Boolean algebra by a cyclic group is proven to have a symmetric chain decomposition. This generalizes earlier work of Griggs, Killian and Savage on the case of prime order, giving an explicit construction for any order, prime or composite. The combinatorial map specifying how to proceed downward in a symmetric chain is shown to be a natural cyclic analogue of the sl2 lowering operator in the theory of crystal bases.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eaigsdhqcbsui5npae82umqcl8","2011-08-10 14:34:55","2011-08-16 13:52:45"
"956","8","An Implicitization Challenge for Binary Factor Analysis","2011-09-21 16:00:00",NULL,"SAS 4201","Maria Angelica Cueto",,"Columbia University",,,"In recent years, tropical geometry has provided useful symbolic tools to address implicitization questions. In this talk, I will describe a successful application of these techniques to compute the multidegree and Newton polytope of the hypersurface of a statistical model with two hidden and four observed binary random variables, solving an open question stated by Drton, Sturmfels and
Sullivant. The model is obtained from the undirected graphical model  of the complete bipartite graph $K_{2,4}$ by marginalizing two of the six binary random variables and it is a special instance of the restricted Boltzmann machines. These machines can be viewed as the binary undirected analog of factor analysis and has been the subject of a recent resurgence of interest due to its role as the building block of the deep belief network. This is joint work with Enrique Tobis and Josephine Yu.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e5bc53co7o5g35cbs3jbqpr6co","2011-08-16 09:50:11","2011-08-19 11:44:20"
"957","8","Tensor Seminar Organizational Meeting","2011-08-24 16:00:00",NULL,"SAS 4201","Seth Sullivant",,"NCSU",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1pntr0bldm45iprf26prvu5b1c","2011-08-16 10:28:45","2011-08-16 10:29:51"
"958","14","Mathematics Fall Departmental Meeting","2011-08-17 16:00:00",NULL,"SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e65a7p172vbg27339m6rhltacg","2011-08-16 15:27:09",NULL
"959","14","Departmental Tea and Cookies","2011-08-17 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n7sej80b16le0v6oojid5d4uqk","2011-08-16 15:27:40",NULL
"960","28","Questions You've Always Wanted to Ask","2011-08-24 16:00:00",NULL,"SAS 1102","AWM Panel","http://www.math.ncsu.edu/GroupsOrgs/AWM/seminars.php","NC State","AWM",,"A panel of representatives will be present to discuss questions with WebAssign, Moodle, travel funds, math library, reserving room, etc. ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e9os1oos3jqmveq88asno477rg","2011-08-18 12:40:47","2011-08-24 10:26:35"
"961","6","An Adaptive Immersed Finite Element Method with Arbitrary Lagrangian-Eulerian Scheme for Parabolic Equations in Variable Domains","2012-03-27 15:00:00",NULL,"SAS 4201","Zhiming Chen",,"Chinese Academy of Sciences","Zhilin Li",,"An adaptive immersed finite element method based on the a posteriori error estimate for solving elliptic equations with non-homogeneous
boundary condition in general Lipschitz domain is proposed. The underlying finite element mesh need not to fit the boundary of the
domain. Optimal a priori error estimate of the proposed immersed finite element method is proved. The immersed finite element method is
then used to solve parabolic problems in time variable domains together with an arbitrary Lagrangian-Eulerian (ALE) time
discretization scheme. An a posteriori error estimate for the fully discrete immersed finite element method is derived which can be used
to adaptively update the time step sizes and finite element meshes at each time step. Numerical results are reported to support the
theoretical results. This is a joint work with Zedong Wu and Yuanming Xiao.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4e8sr9m4bufru321vu8cd0v50s","2011-08-21 15:48:42","2012-02-29 05:40:16"
"962","14","Departmental Tea and Cookies","2011-08-24 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u0302j314n02tusdccn9nt6n2c","2011-08-22 14:23:27",NULL
"963","23","Fundamentals of Latex","2011-08-26 15:00:00",NULL,"SAS 4201","Zhengzheng Hu",,"North Carolina State University","Ralph Smith",,"This will include discussion regarding the installation of Latex on your own machine as well as various typesetting commands and strategies including the incorporation of figures in documents. The presentation will thus include topics of interest for both beginning Latex folks and those interested in some of the more detailed points.

For instructors requiring Latex in class, please feel free to recommend this to students for whom this would be beneficial.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mkevbnmskqqng2lgk4pqctfh9c","2011-08-22 15:19:19",NULL
"964","6","ALIEN: ALgebra for Identification EstimatioN","2011-11-08 15:00:00",NULL,"SAS 4201","Olivier Gibaru",,"Arts et Métiers ParisTech and U. of Lille","NA Seminar",,"We present in this talk a new class of algorithms for on-line estimation issued from an algebraic framework, allowing for concrete applications in various domains. Identification and estimation techniques are, under various guises, present in many parts of control, signal processing and applied mathematics. A huge international literature is concerned with estimation, identication, observers. Unlike traditional methods, which pertain in majority to optimization and asymptotic statistics, the algebraic estimators, originally introduced by Fliess and Sira Ramirez, are non-asymptotic and robust to noises. Our techniques use mathematical tools stemming from algebra, differential algebra, linear algebra over rings, operational calculus and distributions. They result in relatively simple and fast algorithms, with straightforward implementation using standard tools from computational mathematics.

I will adress in this talk, within the area of estimation, the trend of causal Numerical differentiation for on-line applications. I will give some comparison with the classical Kalman-Bucy method. These algebraic numerical estimators were introduced by Mboup, Fliess and Join. We recently extended these non asymptotic estimators which allow us for a class of noisy signals to reduce drastically the time-delay estimation. We also studied the infuence of different corrupted noises. We will show the efficiency of these estimators for the on-line estimations of a nonlinear dynamical model of a six axis robot.

----

Please, note: following this presentation, Eric Nyiri and the speaker will give a talk at the OR Seminar, 4:30-5:45, Daniels Hall, 218, on the theme ""Polynomial spline algorithms using L1-norm in interpolation and approximation"".","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/trgsvr8frg4eptlav4pv51ej5k","2011-08-22 22:35:09","2011-08-31 13:34:39"
"965","24","Math Mixer","2011-08-23 17:00:00",NULL,"SAS 4104",,,,,,"This is just a reminder that MGSA is having a Math Mixer tomorrow on Wednesday, August 24th at 5 pm in the SAS 4th floor lounge. There will be pizza, snacks and refreshments. Everyone in the math department is welcome to join. ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rje5bivu3mapbu826tret4ark8","2011-08-23 10:48:01",NULL
"966","6","Semi-implicit time integration scheme for  fluid-structure interaction problems","2011-10-25 15:00:00",NULL,"SAS 4201","Ricardo Ortiz","http://www.unc.edu/~ricortiz/","UNC-CH","NA Seminar",,"We present a time-stepping scheme to solve stiff ODEs that arise from models that include fluid-structure interaction in a viscous fluid. The scheme is based on a semi-implicit formulation of the method of spectral deferred corrections for ODEs (SISDC). We deal with the stiffness by splitting the right hand side of the ODE into a stiff and non-stiff terms and treat each of them accordingly. We use this method to simulate immersed boundaries in a Stokes fluid.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8ipamnn5vrhsj5ofvtsj7tbqhc","2011-08-23 13:13:14","2011-10-20 15:40:22"
"968","4","The Erpenbeck high-frequency instability theorem for ZND detonations.","2012-03-14 15:00:00",NULL,"SAS 4201","Mark Williams","http://www.unc.edu/~williams","University of North Carolina at Chapel Hill","Steve Schecter",,"The rigorous study of spectral stability for strong detonations  was begun by J.J. Erpenbeck in the 1960s.  Working with the ZND model, which assumes a finite reaction rate but ignores effects like viscosity corresponding to second order derivatives, he used a normal mode analysis to define a stability function V(\tau,\epsilon), whose zeros in Re \tau > 0 correspond to perturbations of a steady detonation profile that grow exponentially in time.   In a remarkable paper he provided strong evidence, by a combination of formal and rigorous arguments, that for certain classes of steady ZND profiles, unstable zeros of V exist for perturbations of sufficiently large transverse wavenumber \epsilon, even when the von Neumann shock, regarded as a gas dynamical shock, is uniformly stable in the sense  defined (nearly twenty years later) by Majda.  In spite of a great deal of later numerical work devoted to computing the zeros of V, Erpenbeck's paper remains one of the few works that presents a detailed and convincing theoretical argument for detecting them.

Erpenbeck's analysis points the way toward, but does not constitute, a mathematical proof that such unstable zeros exist.    In this talk we identify the mathematical issues left unresolved  by Erpenbeck and discuss how one can prove, simplify, and extend his results about stability and instability of strong detonations.

The underlying mathematical problem is to determine the precise asymptotic behavior as \epsilon\to \infty of solutions to a linear system of ODEs in x, depending on \epsilon and a complex frequency \tau as parameters, with turning points x* on the half-line [0,\infty). This is joint work with K. Zumbrun and O. Lafitte.
","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2os3qi7onvbar2m6loom0as7r8","2011-08-24 10:09:46","2012-02-23 12:52:18"
"969","21","SIAM Conference on Applied Algebraic Geometry","2011-10-06 08:00:00","2011-10-09 17:00:00","Riddick and Withers Halls",,,,,"http://www.siam.org/meetings/ag11/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pcr5gs401tgcm5npjsbi7jhgjg","2011-08-24 14:52:43",NULL
"970","8","Introduction to Symmetric Tensor Decomposition","2011-08-31 16:00:00",NULL,"SAS 4201","Agnes Szanto",,"NC State",,,"We will begin reading and discussing the paper: Pierre Comon, Gene Golub, Lek-Heng Lim, Bernard Mourrain, ""Symmetric tensors and symmetric tensor rank"".","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l4p0ajssl6vgsc06hk6r41sa0c","2011-08-24 15:39:53","2011-08-31 10:09:43"
"971","8","Introduction to Symmetric Tensor Decomposition, Continued","2011-09-07 16:00:00",NULL,"SAS 4201","Seth Sullivant",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/10spqagm6f4gfdu15d47tju8jo","2011-08-24 15:41:50",NULL
"972","3","Sieving with generating functions","2011-09-23 16:00:00",NULL,"SAS 4201","Andrew Berget","http://www.math.ucdavis.edu/~berget/","University of California, Davis","Alex Fink",,"Let X be a set of combinatorial objects and X(t) a generating function for these elements according to some natural statistic. For example, X could be the set of k-subsets of {0,1,..,n-1} and X(t) is recording the sum of the numbers in a particular subset in the exponent of t. Sometimes, like in the example just mentioned, setting t equal to an appropriate root of unity counts the number of elements of X with a certain cyclic symmetry.

In this talk, I will discuss and generalize this ""cyclic sieving phenomenon"" (due to Reiner, Stanton and White). All the examples will consist of multi-variate generating functions whose evaluations at certain roots of unity count objects with various symmetries. Two examples figuring prominently will be words of fixed length on a fixed alphabet, and the finite Grassmannian, Gr(r,n)(F_q).

This is joint work with Sen-Peng Eu, Jia Huang and Vic Reiner.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u8asghpeiokl8jcgtl772thieo","2011-08-24 21:03:57","2011-08-31 08:14:48"
"973","4","Propagating two-dimensional magnetic droplets","2011-10-26 15:00:00",NULL,"SAS 4201","Matteo Sommacal","http://www4.ncsu.edu/~msommac","NC State","Mark Hoefer",,"Recent results on propagating, solitary magnetic wave solutions of the Landau-Lifshitz equation with uniaxial, easy-axis anisotropy in thin (two-dimensional) magnetic films will be illustrated. These localized, nontopological wave structures, parametrized by their precessional frequency and propagation speed, extend the stationary, coherently precessing ""magnon droplet'"" to the moving frame, a non-trivial generalization due to the lack of Galilean invariance. Propagating droplets move on a spin wave background with a nonlinear droplet dispersion relation that yields a limited range of allowable droplet speeds and frequencies. The droplet is found to propagate as a nonlinear Schroedinger bright soliton in the weakly nonlinear regime. An iterative numerical technique is used to compute the propagating droplet's phase, amplitude, energy, momentum, width, and more. Time-dependent numerical simulations confirm the propagating droplet's stability when its frequency and speed lie within the allowable range.

This research has been carried out in collaboration with Mark Hoefer.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o7ogf4q0o91mors746fvfruvno","2011-08-25 17:14:10","2011-10-21 09:40:16"
"974","22","Tiling the Aztec diamond with dominoes","2011-08-31 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/083111.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u6iq2dkj429kev0gka2ni624ik","2011-08-26 09:57:46","2011-08-31 14:55:56"
"975","22","How the Talmud Divides an Estate Among Creditors","2011-09-07 16:00:00",NULL,"SAS 2102","Steve Schecter",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/090711.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lhc8ib397b4o26vhl6435kp3ug","2011-08-26 09:58:52","2011-08-31 14:57:22"
"976","22","The Mathematics of Voting","2011-09-14 16:00:00",NULL,"SAS 2102","Molly Fenn",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/091411.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6mf4bh1r3pi8ac80crjnt5kejo","2011-08-26 09:59:21","2011-09-07 09:07:22"
"977","22","Reflections at the heart of symmetry","2011-09-21 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/092111.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3uqv426of10f12qipba0i3f7nk","2011-08-26 10:00:26","2011-09-19 11:21:02"
"978","22","Differential Inequalities","2011-10-12 16:00:00",NULL,"SAS 2102","Robert Martin",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/101211.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o2cf77f75td3mkpm0pfd4q1vqs","2011-08-26 10:02:32","2011-10-05 16:03:44"
"979","4","Two-phase flow in porous media: the Saffman-Taylor instability revisited","2011-09-21 15:00:00",NULL,"SAS 4201","Michael Shearer","http://www4.ncsu.edu/~shearer/home0.html","NC State",,,"Plane waves for two-phase flow in a porous medium are modeled by the one-dimensional Buckley-Leverett equation, a scalar conservation law. We analyze linearized stability of sharp planar interfaces to two-dimensional perturbations, which involves a system of PDEs. Numerical simulations of the full nonlinear system, including dissipation, illustrate the analytical results. We also discuss a modified Buckley-Leverett equation, in which the capillary pressure is rate-dependent, thereby adding a BBM-type dispersive term. This equation sustains undercompressive planar waves, but they are all unstable to two-dimensional perturbations. This is joint work with Kim Spayd and Zhengzheng Hu.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ma58cj0kmk94undsk94t3lpnmk","2011-08-26 10:51:36","2011-09-15 09:55:06"
"980","3","Quantum affine algebras via smash products","2011-09-02 16:00:00",NULL,"SAS 4201","Garrett Johnson",,"NC State",,,"For every element w in the Weyl group of a simple Lie algebra g, De Concini, Kac, and Procesi (DKP) defined a subalgebra U_q^w of the quantized universal enveloping algebra U_q(g). The algebra U_q^w is a deformation of the universal enveloping algebra U(n_+\cap w.n_-). Some important examples of DKP algebras associated to finite Weyl groups include the algebras of quantum matrices, quantum affine space, and quantum Euclidean space. I will describe a smash product construction that produces DKP algebras associated to the affine Weyl groups from some of the finite-type DKP algebras listed above. This is joint work with Chris Nowlin.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/neieo6vc1gqlplueljhfij5gdg","2011-08-26 15:04:05","2011-08-28 13:22:55"
"981","8","Tensor Seminar:  Tensors in Signal Processing","2011-10-19 16:00:00",NULL,"SAS 4201","Chirag Lakhani",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ud3m6elhio4rgs2g5s7rt7thts","2011-08-27 15:06:00",NULL
"982","9","Investigating the genetic basis of adaptive wing color patterns in Heliconius butterflies","2011-09-01 16:00:00",NULL,"Cox Hall, Room 306","Megan Supple",,"NC State, Biomathematics",,,"Investigating the genetic basis of adaptive wing color patterns in 
Heliconius butterflies 

Megan Supple, NC State Biomathematics Graduate Program

Heliconius butterflies offer an excellent opportunity to study adaptive 
phenotypes in natural populations.  Three unlinked loci control the amazing 
amount of variation in wing color patterns that warn potential predators 
that the butterflies are unpalatable.  Recently, the gene driving differences
in red color pattern elements has been identified.  However, polymorphisms 
in the coding region of this gene, optix, show all synonymous mutations, 
indicating that red color pattern changes are driven by regulation of the 
optix gene.  Using a variety of techniques, we are investigating the genomic 
region surrounding the optix gene in order to identify the regulatory 
mechanism that drives differences in optix expression and ultimately results 
in changes in red color pattern elements.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ceci7ltrba4057qf8fnfisc2u8","2011-08-28 12:19:43","2011-08-28 12:20:01"
"983","9","Optical Coherence Tomography for Patient-specific 3D Artery Reconstruction and Evaluation of Wall Shear Stress in a Left Circumflex Coronary Artery","2011-09-22 16:00:00",NULL,"Cox 306","Laura Ellwein",,"Marquette University","Mette Olufsen","http://www.ncsu.edu/biomath/abstracts/ellwein_seminar_11.txt",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q7llukrqlh6sjeco8nvuus7uic","2011-08-28 12:22:50","2011-09-20 15:28:28"
"984","4"," Evaporation waves in a spherically symmetric cone-shaped nozzle","2011-09-14 15:00:00",NULL,"SAS 4201","Xiao-Biao Lin","http://www4.ncsu.edu/~xblin","NC State",,,"This talk is motivated by ongoing  work with Haitao Fan and Martin Wechselberger on evaporation as a fluid passes through a nozzle.   The system  consists of  a KPP-type  reaction-diffusion equation that models the liquid-vapor phase transition, coupled with a  viscous p-system that models the fluid passing through the nozzle. In an unbounded domain, stability of the KPP waves is usually treated by weighted norms introduced by Sattinger (1976). In a bounded domain, it is not possible to directly impose weights for the KPP-type waves.  In this talk we study boundary conditions that lead to well-posedness and stability of the KPP waves with convection.  We show that the boundary conditions at both ends of the domain  may be used to select the ""correct weight""  for the internal layer, and that Sattinger's result can still be useful in proving the stability  of  internal layer solutions.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/utbga454us9pacc811cjghchic","2011-08-28 22:22:30","2011-09-06 15:01:12"
"985","3","Minimal free resolutions of rigid monomial ideals","2011-11-11 16:00:00",NULL,"SAS 4201","Sonja Mapes","http://www.math.duke.edu/~smapes/","Duke",,,"In this talk I will give a definition of what rigid monomial ideals
are and discuss how they are a generalization of generic monomial
ideals.  I will also give a description of how to construct the
minimal resolution of a certain class of rigid monomial ideals.  The
methods we use focus mostly on using the lcm-lattice of the given
monomial ideal, which is a finite atomic lattice, and using the
lattice of all finite atomic lattices with a fixed number of atoms.  I
will conclude the talk with a discussion of how our methods fail for
rigid monomial ideals in general and give a description of current
work which hopes to get around these difficulties.  This work is joint
with Tim Clark.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f4tjtspsm0a8se6s3jicnrnukc","2011-08-29 17:28:31","2011-10-26 20:55:17"
"986","8","Student Talks -- Note Unusual Day","2011-09-29 16:00:00",NULL,"SAS 4201","James Rohal and Matthew Comer",,"NC State",,,"James Rohal

Connectivity in Semi-Algebraic Sets

A semi-algebraic set is a subset of real space defined by
polynomial equations and inequalities and is a union of finitely many maximally connected components. We consider the problem of deciding whether two given points in a semi-algebraic set are connected; that is, whether the two points lie in the same connected component. In particular, we consider the semi-algebraic set defined by f != 0 where
f is a given polynomial. The motivation comes from the observation that many important or non-trivial problems in science and engineering can be often reduced to that of connectivity. We will describe a method based on gradient fields and provide a proof of correctness using the Morse complex.


Matt Comer

The Berlekamp/Massey Algorithm and Counting Singular Hankel Matrices over a Finite Field

We derive an explicit count for the number of singular square Hankel (Toeplitz) matrices whose entries range over a finite field by observing the execution of the Berlekamp/Massey algorithm on its elements.  Our method yields explicit counts also when some entries above or on the anti-diagonal (diagonal) are fixed.  We also derive the count for all square Hankel matrices of a particular rank with generic rank profile, i.e., whose first rank-many leading principal submatrices are non-singular and the rest are singular.  This result generalizes to block-Hankel matrices as well.  This is joint work with Erich Kaltofen","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jjp450s0k51i1476j4s5o04n40","2011-08-30 09:40:40","2011-09-23 09:52:04"
"987","4","Surface segregation and solute trapping during the growth of thin films","2011-10-19 15:00:00",NULL,"SAS 4201","Xiaoying Han","www.auburn.edu/~xzh0003","Auburn University","Xiao-Biao Lin",,"In materials science and engineering, the development and refinement of molecular beam epitaxy (MBE) has been among the most important advances in crystal growth during the past two decades.  My talk will address some issues in MBE that have fundamental importance for understanding crystal growth for technological applications, such as quantum well lasers for semiconducting systems, and giant magnetoresistance for metallic systems.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l0vjq8c79ap0h0gmdgpcrsjreo","2011-08-30 12:35:58","2011-10-10 17:02:05"
"988","14","Departmental Tea and Cookies","2011-08-31 14:30:00",NULL,"SAS 4201",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/c96e9v3pujl3b40eno37m1hbdc","2011-08-30 16:13:06",NULL
"989","3","No talk","2011-11-04 14:00:00",NULL,,,,,,,"We encourage you to attend today's seminars at Chapel Hill: see http://www.math.ncsu.edu/TLC/.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h12kvlhubmou28aigiq3dp8qrc","2011-08-31 13:24:28","2011-10-23 14:34:21"
"990","1","Pseudo-Transient Continuation","2012-03-15 16:00:00",NULL,"SAS 1102","Tim Kelley","http://www4.ncsu.edu/~ctk","NC State: Distinguished Faculty Colloquium","Your tax dollars at work",,"The convergence theory for Newton's method says that either the iteration will converge rapidly to a solution from a given initial iterate, or fail in one of two easy-to-detect ways. The failure modes include (1) convergence to an incorrect (i.e., non-physical or dynamically unstable) solution, (2) divergence to infinity, and (3) stagnation at a singularity of the Jacobian. The classic theory will count (1) as a success, but shouldn't.

Pseudo-transient continuation is a way to enforce dynamic stability of the solution of a nonlinear equation  and thereby increase the chances that the limit of the Newton iteration is a useful solution. This approach can also help one avoid stagnation. In this talk we will describe the method and some of the recent convergence results. We will also discuss some of the many applications, and show how nonsmooth analysis can connect theory and practice.

Five of my PhD students, one postdoc, and three colleagues from MAE were involved in this project. 

This presentation should be understandable to anyone who is good at calculus.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/gkh2778vvqrjahq34dv432q7os","2011-09-02 09:35:35","2012-02-29 18:07:03"
"991","3","Thom polynomials","2011-10-14 16:00:00",NULL,"SAS 4201","Richárd Rimányi","http://www.unc.edu/~rimanyi/","UNC Chapel Hill","Alex Fink",,"The topology of the spaces A and B may force that every map from A to B must have certain singularities. For example, a map from the Klein bottle to 3-space must have double points.
These forced degenerations are measured by the so-called Thom polynomials of singularities. Special cases include Schur, Schubert, and quiver polynomials. In the lecture we will explore the theory of Thom polynomials, their role in algebraic combinatorics, and their applications.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mgrma9i8ak2p80pgcn2gb4b3ls","2011-09-03 16:31:39","2011-10-09 17:53:03"
"992","3","Log concavity of characteristic polynomials and toric theory","2011-10-21 16:00:00",NULL,"SAS 4201","Eric Katz","http://www.math.uwaterloo.ca/CandO_Dept/","Waterloo","Alex Fink",,"In recent joint work with June Huh, we proved the
log concavity of the characteristic polynomial of a realizable matroid
by relating its coefficients to intersection numbers on an algebraic
variety and applying an algebraic geometric inequality.  This extended earlier work of Huh which resolved a conjecture in graph theory.  In this talk, we rephrase the problem in terms of more familiar algebraic geometry, outline the proof, and discuss an approach to extending this proof to all matroids.  Our approach suggests a general theory of positivity in tropical geometry.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hvniab2ssnop5tkd2g7udg1tlo","2011-09-04 12:28:10","2011-10-17 10:00:54"
"993","3","Cluster algebras and Coxeter combinatorics","2011-09-16 16:00:00",NULL,"SAS 4201","Nathan Reading",,"NC State",,,"I will give a brief overview of the Coxeter-theoretic approach to the combinatorics of cluster algebras, via sortable elements and Cambrian lattices.  I won't assume any background in Coxeter groups or cluster algebras, and as a result, I will need to cover this background only very superficially.  The focus of the talk will be to communicate some of the basic ideas and intuition.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4j29p79evf750cu3fbv8eqc6to","2011-09-05 09:58:37",NULL
"994","4","Geometric and probabilistic descriptions of chaotic phase-space transport","2011-11-09 15:00:00",NULL,"SAS 4201","Shane Ross","http://www.esm.vt.edu/~sdross","Virginia Tech","Dmitry Zenkov",,"Several geometric and probabilistic methods for studying chaotic phase-space transport have been developed and fruitfully applied to diverse areas from orbital mechanics to biomechanics to fluid mechanics and beyond. Increasingly, systems of interest are determined not by analytically defined model systems, but by data from experiments or large-scale simulations. This emphasis on real-world systems sharpens our focus on those features of phase-space transport in finite-time systems that seem to be robust, leading to the consideration of not only invariant manifolds and invariant manifold-like objects, but also their connection with concepts such as symbolic dynamics, braids, and almost-invariant sets. This talk will address systems known analytically from which phase-space structures (separatrices) controlling transport and stability can be computed, and approaches for identifying separatrices and quantifying transport in mechanical systems not known analytically. Applications to areas such as celestial mechanics, musculoskeletal biomechanics, ship capsize prediction, and atmospheric microbe transport will be discussed. 
","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eqk57o80cqstq6c1eb43vtmvbk","2011-09-05 19:01:29","2011-10-26 16:20:51"
"996","6","Atomistic simulations of vibration of carbon nanotubes: is it possible to measure the mass of a single atom?","2011-10-28 14:00:00",NULL,"SAS 4201","Polina pine",,"Technion, Israel","Tim Kelley","http://www4.ncsu.edu/~ctk/Pine_Abstract.pdf","Carbon nanotubes are long thin tubes made from rolled up single sheets of graphene. Nanotube resonators have already reached the mass sensitivity required to measure the mass of single molecules, but in order to detect smaller (atomic) masses these devices must be further optimized. For this, a deep understanding of their operational mechanism is required, but simple analytic models and previous simulations have internal contradictions leading to questions such as whether the Young's modulus of nanotubes is a well defined concept.
We have made careful, extensive, atomistic Molecular Dynamics simulations of nanotubes using the Brenner potential. The nanotube vibrations were recorded at selected points and decomposed into vibrational modes using a Fourier Transform technique. The nanotubes were first slowly thermalized to 300 degrees K with periodic boundary conditions then clamped to retain its at the mean length. Different lengths and radii were studied and we developed protocols for dealing with the large quantity of data generated. (Each nanotube is allowed to vibrate 1000 times more than the period of its lowest frequency and we use a timestep of 0.5fm).
The simulations provide clear evidence for the failure of simplistic analytic models to accurately extract resonance frequencies as a function of the ratio between the tube's radius and length as the latter increases. Our results agree with the Timoshenko beam model (which includes the effect of both rotary inertia and of shearing deformation) and partially resolve Yakobson's paradox concerning the Young's modulus, and provide an upper cutoff estimate for the effective wall thickness. We have further made a comparison of the vibrational behavior of different types of nanotubes: zigzag, armchair and two chiral types. This gives the surprising result that nanotube structure/chirality does not affect the vibrational frequencies under double clamping conditions. In the laboratory, nanotubes are not fully clamped as in models and some simulations. Only atomistic simulations can truly model partial clamping. Our latest simulations with partial clamping show that under such conditions the degeneracy lifts and we can propose which type of nanotube would be the best candidate to progress towards weighing single atoms.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9pdnfj7v1ami0tsfjrhaotqino","2011-09-06 09:43:36",NULL
"997","23","Applying for Graduate Research Fellowships","2011-09-09 15:00:00",NULL,"SAS 4201","Seth Sullivant",,"North Carolina State University","Ralph Smithg",,"Seth will give a one hour presentation on graduate research fellowships this Friday, September 9, 2011.  We will focus on the NSF graduate research fellowship, but the basic ideas apply to many other possible fellowship:  (NDSEG fellowship, Hertz Foundation Fellowship, DOE Fellowship, etc.).  The awards can make a huge difference in your graduate career, freeing you from teaching responsibilities and giving you more time for research.

The NSF fellowship is available to US citizens, Nationals, and permanent residents, who are either in their final year of undergraduate school, or in their first or second year of graduate school at the time of application, and who plan on doing graduate research in science, engineering, or mathematics.  The presentation will focus on the three two-page essays that are required in the application: the personal statement essay, the previous research experience essay, and the proposed plan of research essay.  You can find more details about the fellowship here:

http://www.nsfgrfp.org/

If you plan on applying for these fellowships, the time to start working on these essays is now, before the busy-ness of the Fall semester sets.

","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q88j71ntqc2t2u033aar4f9118","2011-09-06 10:41:52",NULL
"998","14","Departmental Tea and Cookies","2011-09-07 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/h6bcitrnumk41sqbmhefrnsan4","2011-09-06 21:25:08",NULL
"999","3","The shape of a random affine Weyl group element, and random core partitions","2011-11-07 11:30:00",NULL,"SAS 4201","Thomas Lam","http://www.math.lsa.umich.edu/~tfylam/","U Michigan",,,"I will discuss the ""shape"" of a random element of an affine
Weyl group, where an element is randomly generated by (reduced)
multiplication by simple generators. This is equivalent to looking at
a random walk in the affine Coxeter arrangement that is conditioned to
never cross a hyperplane twice. I will also connect this problem to
the shape of random core partitions.
","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/706hrja54ngdj78qqk6ul64h90","2011-09-07 15:19:35","2011-11-03 21:02:36"
"1000","1","What do mosquitofish, shrimp, and proliferating CD4+ T-cells have in common?","2011-11-17 16:00:00",NULL,"SAS 1102","H. T. Banks",,"NC State: Distinguished Faculty Colloquium",,,"The short answer is uncertainty in dynamics and data measurements. In this talk, which we hope to make accessible and fun for undergraduates, graduate students and postdocs (and even some older faculty!), we discuss some recent projects involving probability, statistics and, of course, mathematics. We will focus on a recent (2005-2008) project with Advanced BioNutrition Corporation of Columbia, Maryland, on development of models for shrimp populations as a scaffold in a rapid vaccine-production system. We will explain how some basic questions in the science of this project have led our team members to longer-term research questions in modeling and computation of variability and uncertainty. We hope to do this in such a way that no specific facts from probability and statistics are required to understand the presentation. (So all you deterministic folks are most welcome and are in fact urged to attend. As one of our colleagues might say, “It could be a life-altering experience!”)","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/ev3csb8aq24mbog52g09a4gs0s","2011-09-07 17:16:57","2011-11-08 09:14:03"
"1001","1","The art of hybrid computation","2012-02-16 16:00:00",NULL,"SAS 1102","Erich Kaltofen","http://www4.ncsu.edu/~kaltofen","NC State: Distinguished Faculty Colloquium",,,"Hybrid symbolic-numeric computation is the fifth of the ""Seven Dwarfs of Symbolic Computation"", which I listed in my 2008 SNSC talk in Hagenberg. ""Hybrid"" means that the solution of a computational problem uses both numeric and symbolic algorithmic components.

I will survey some important results about hybrid methodology and discuss the lessons I have learned from them. In particular I will discuss approximate GCD, approximate sparse interpolant (signal) from noise, outlier errors in the input scalars, and analysis of the random distribution of matrix condition numbers in randomized hybrid algorithms.

One can bypass this analysis by producing an exact certificate, and I will give sum-of-squares certificates in global optimization via our ArtinProver software. Specifically, I will discuss exact certificates of impossibility of sum-of-squares representation based on the Farkas Lemma of semidefinite programming.

This work is in collaboration with Matthew Comer, Feng Guo, Wen-shin Lee, Zhengfeng Yang, and Lihong Zhi.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/s7p88a99q015m80cdr5k195dvk","2011-09-07 17:22:53","2012-02-03 12:08:40"
"1002","1","Estimating population eigenvalues from large  dimensional sample covariance matrices","2012-04-10 16:00:00",NULL,"SAS 1102","Jack Silverstein","http://www4.ncsu.edu/~jack","NC State: Distinguished Faculty Colloquium",,"http://www.math.ncsu.edu/events/silverstein_coll.pdf",,"schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/pu5ilarbr47kk6gk7bbekdpgsk","2011-09-07 17:26:19","2012-04-02 14:52:06"
"1003","26","Mathematical Modeling of Dynamic Responsiveness for Human Lymphocyte","2011-09-12 16:00:00",NULL,"SAS 4201","Clay Thompson","http://www4.ncsu.edu/~wcthomps/","NC State Mathematics Graduate Student",,"TBA","CFSE analysis of a proliferating cell population is a popular tool for
the study of cell division and division-linked changes in cell
behavior. A recent revision of a previous partial differential
equation (PDE) model is presented to describe lymphocyte dynamics in a
CFSE proliferation assay. The previously unknown physical mechanisms
accounting for the exact degree of dye dilution by division are shown
to be a consequence of cellular autofluorescence. The rate at which
label decays/diffuses out of the cell is also quantified using a
Gompertz decay process. By fitting the new model to the commonly used
histogram representation of the data, it is shown that these
improvements result in a model with a strong physical basis which is
still fully capable of replicating the behavior observed in the data.
Some mathematical aspects of the inverse problem are discussed. The
new model provides quantitative data which should prove useful for the
comparison of CFSE proliferation assay data across different data sets
and experimental conditions.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4v91phpan0vsovb6hvio7s9qec","2011-09-07 18:40:43",NULL
"1004","14","Departmental Tea and Cookies","2011-09-14 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e1n751cb8ghm4vn0a4een29ab4","2011-09-09 14:53:04",NULL
"1005","12","Total UQ","2011-09-15 15:30:00",NULL,"SAMSI, room 150, Durham","Tony O'Hagan",,,,,"In this colloquium I will set out my ideas about UQ methodology and what it  would mean to quantify *all* uncertainties - Total UQ.  The perspective is fully  Bayesian and pragmatic, although the Total UQ programme as a whole is very  ambitious.  I will end by identifying some specific challenges within this  framework where progress might reasonably be achieved within the SAMSI UQ program this year.

http://www.samsi.info/visitors/directions","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ba26b09e594284rcf3aidoamkg","2011-09-12 10:17:51",NULL
"1006","23","Poster Design","2011-09-16 15:00:00",NULL,"SAS 4201","Mandy Smith and Colleen McCarthy",,"North Carolina State University","Ralph Smith",,"Posters comprise an increasingly popular medium to disseminate research at conferences and workshops and are becoming required at certain meetings.  However, the design of effective posters differs significantly from that of research talks.

The speakers will discuss techniques pertaining to highly effective poster design and construction using various software.  Additionally, there will be general discussion regarding the layout of effective posters.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2uqv0krqual174ed0or91p581o","2011-09-12 17:25:37",NULL
"1007","23","Fundamentals of Webdesign Using Dreamweaver","2011-09-23 15:00:00",NULL,"SAS 4201","Seyma Bennett-Shabbir",,"North Carolina State University","Ralph Smith",,"Effective webpages are an increasingly important medium for
disseminating information related to classes and research.  For TA's, they provide a critical way to share material with your class whereas for those entering the job market, they are often checked by potential employers interested in obtaining more information about candidates.  Hence it is important to construct and maintain your webpage in a manner that is both easy and professional.

In this session, Seyma will discuss the use of Dreamweaver, which is one of the most widely used software packages for webpage design.  Dreamweaver is available on machines in the Multimedia Center and across campus.  Seyma will bring the labtop cart so you will get hands on experience.

For those who are unable to attend this session, you can obtain individual help from Seyma by stopping by her office.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vsdpbume1e5ctfagvvmgsjgmtg","2011-09-12 17:29:17",NULL
"1008","4","Canard cycles in predator-prey systems","2011-09-28 15:00:00",NULL,"SAS 4201","Huaiping Zhu","http://www.math.yorku.ca/~huaiping","York University","Zhilin Li",,"There have been extensive stability and bifurcation studies of predator-prey systems, yet the study of canard cycles of such systems is rather limited due to technical difficulties in dealing with the degenerate singularities.  In this talk, by using center manifolds and geometric singular perturbation theory, I will present bifurcation studies of canard cycles in predator-prey systems, and apply the results to obtain canard cycles in models with different Holling types of functional responses. This is a joint work with Chengzhi Li.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/50k4798n3a6vi8qv6ni8tl2ts4","2011-09-15 09:59:11","2011-09-19 09:50:40"
"1009","26","Investigating the influence of Atropine on heart rate regulation","2011-09-19 16:00:00",NULL,"SAS 4201","Christian Haargaard Olsen",,"NC State Mathematics Graduate Student",,"TBA","Some people suffer from a condition that prevents their body to control the blood flow to the brain properly. This can cause different problems, including syncope and dizziness. We collaborated with a physician at Frederiksberg Hospital in Denmark who has done experiments with people suffering from bad blood control where he measures the subjects blood pressure and heart rate response to being tilted from lying to standing. We used a model of ordinary differential equations to predict the heart rate from the blood pressure at Carotid Sinus (In the neck). I will present the model we used, explain a little about the physiology, tell about the numerical method we used for parameter estimation and show some of our results.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cr79fcf76ndi7g7h5fempb58e4","2011-09-16 09:32:10","2011-09-16 10:46:15"
"1010","14","Departmental Tea and Cookies","2011-09-21 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/a2gp6br0sb2stjsngd479n3d8c","2011-09-19 09:50:32",NULL
"1011","22","Avalanches and the Brazil Nut Effect","2011-09-28 16:00:00",NULL,"SAS 2102","Michael Shearer",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/092811.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kd55tlqmfat11san6m8cni3e4k","2011-09-19 11:19:28",NULL
"1012","22","Putting a Spring in Yoda's Step","2011-11-02 16:00:00",NULL,"SAS 2102","Tim Chartier","http://www.davidson.edu/math/chartier/","Davidson College",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/110211.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/epl9ppl23b7ltpcicdk2fad70s","2011-09-19 11:23:31","2011-10-26 10:24:54"
"1013","22","Putting the Pieces Together: The Math of Puzzle Assembly","2011-11-09 16:00:00",NULL,"SAS 2102","Susan Crook",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/110911.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1r3aa5d8r2rspbrc7b2fje00lg","2011-09-19 11:25:07","2011-11-02 10:47:50"
"1014","28","First AWM Meeting of the Year","2011-09-22 14:00:00",NULL,"SAS 2102","Susan Crook","http://www.math.ncsu.edu/GroupsOrgs/AWM/index.php","AWM","AWM",,"We'll be getting together to plan for the upcoming SK-Day.","mmtolley","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6ssebeja92jrp1khlbd70m34os","2011-09-20 12:10:08",NULL
"1015","4","Monte Carlo simulations informed by large deviation principles","2012-04-11 15:00:00",NULL,"SAS 4201","Richard Moore","http://web.njit.edu/~rmoore","Mathematical Sciences, New Jersey Institute of Technology","Mark Hoefer",,"Many systems of physical interest are well-approximated by low-dimensional reductions over a limited range of behavior. This makes the reduced system very useful in computing, for example, the first few moments of a distribution induced by stochastic perturbations to the full system. When computing the probability of rare events, however, the reduced system is rarely accurate enough to produce reliable statistics. Nevertheless, the most likely paths produced by large deviation techniques applied to the reduced system are often very useful in guiding Monte Carlo simulations performed on the full system. I will discuss examples of this approach in the context of fiber-optic communications and mode-locked lasers. Time permitting, I will also discuss the application of this idea to data assimilation.","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/svjrg43q0rj7mkbaen6u7h2r24","2011-09-20 13:16:31","2012-04-05 11:59:51"
"1016","19","The Geometry of Tree Reconstruction","2011-09-30 15:00:00",NULL,"SAS 2235","Ruth Davidson","http://www4.ncsu.edu/~redavids/","NC State Mathematics Graduate Student",,,"Tree agglomeration methods such as the Neighbor-Joining method and UPGMA continue to play a significant role in phylogenetic research. Polyhedral combinatorics and linear optimization offer a robust toolkit for analyzing the natural subdivision of Euclidean space induced by classifying the input vectors according to tree topologies returned by the algorithm. Our analysis shows connections between the cones associated to UPGMA trees and other combinatorial objects including the partition lattice.  We give a closed form for the extreme rays of UPGMA cones on n taxa.  This is joint work with Seth Sullivant.","njschwar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ovtu4t55m3i22qcfm6mbffdu3g","2011-09-20 14:05:24",NULL
"1017","21","2011 Todd Fuller Contest","2011-10-15 09:00:00",NULL,"Mann Hall room 216",,,,,"http://www.math.ncsu.edu/undergrad/ncsu_contests/2011/index.php",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/h615dppf14qt1c4585t2756d4c","2011-09-22 16:28:45","2011-10-12 15:23:33"
"1018","21","Sonya Kovalevsky Day","2011-10-22 09:00:00","2011-10-22 15:15:00","SAS Hall","Association for Women in Mathematics",,"NC State",,"http://www.math.ncsu.edu/GroupsOrgs/AWM/events.php","This is a program of workshops, talks, and problem-solving competitions for female high school or middle school students and their teachers, both women and men. The purposes are to encourage young women to continue their study of mathematics, to assist them with the sometimes difficult transitions between middle school and high school mathematics and between high school and college mathematics, to assist the teachers of women mathematics students, and to encourage colleges and universities to develop more extensive cooperation with middle schools and high schools in their area. Please register online at https://www.math.ncsu.edu/forms/AWM/app/","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8hs1nlbshfhomqspm5vh9bp2b0","2011-09-22 16:34:13",NULL
"1019","26","Distributions on Electric Permitivity in Maxwell's Equations","2011-09-26 12:00:00",NULL,"SAS 4102","Zack Kenz","http://www4.ncsu.edu/~zrkenz/","NC State",,,"Electromagnetic interrogation is one method that can be used for nondestructive evaluation of materials. In order to identify the presence of damage in an object under study, we will characterize the electric permittivity of the material. This presentation will review portions of the work of Banks, Buksas, and Lin [BBL] and of Banks and Gibson [BG]. In BBL, the authors consider the well-posedness of estimating a single polarization relaxation time in a Debye or Lorentz material. In works by BG, the authors expand the results of BBL to incorporate distributions on relaxation times in a Debye material.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mub22hp76ab4u1p72194806edg","2011-09-23 08:28:56",NULL
"1020","4","The onset of steady vortices in Taylor-Couette &#64258;ow: the role of approximate symmetry","2011-11-02 15:00:00",NULL,"SAS 4201","David Schaeffer","http://fds.duke.edu/db/aas/math/dgs","Duke University","Michael Shearer",,"The onset of steady cellular motion in the flow between rotating concentric cylinders is the preeminent example of a hydrodynamic instability in an internal fluid flow. In his 1923 paper, Taylor obtained remarkable agreement between experimental results and theoretical predictions for the onset of instability in this geometry, agreement that remains unsurpassed in fluid mechanics to this day. This problem is often considered as an example of a pitchfork bifurcation in the Navier Stokes equations. This view would be valid if the flow could be modeled as periodic along the length of the cylinder. More accurately, one should expect ‘end e&#64256;ects’ to disconnect the pitchfork of the idealized problem. Taylor’s own results and many subsequent experiments and simulations have appeared to con&#64257;rm this ‘imperfect bifurcation’ conceptual model. However, end e&#64256;ects in the finite-length case are not a small perturbation of the problem with periodic boundary conditions. Specifically, no matter how long the apparatus, finite-length e&#64256;ects greatly perturb the disconnected branch of the pitchfork of the periodic model (what Benjamin calls anomolous-mode flows). On the other hand, in long cylinders these e&#64256;ects appear to change the connected branch (normal-mode &#64258;ows) only minimally. We propose a resolution of this seemingly contradictory behavior in terms of a symmetry-breaking bifurcation. The relevant symmetry, which is only approximate, is between two normal-mode &#64258;ows with large, and nearly equal, numbers of cells, quite different from the familiar translational symmetry of the periodic problem.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dph086op59f5rudqfg66ns9f1g","2011-09-23 18:29:15",NULL
"1021","14","Departmental Tea and Cookies","2011-09-28 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sq3tn19jgtj4uq8ah8vf31c8n4","2011-09-25 19:46:53",NULL
"1022","23","Graphics Packages","2011-09-30 15:00:00",NULL,"SAS 4201","RTG Faculty",,"North Carolina State University","Ralph Smith",,"Many papers and presentations require the use of graphics packages to construct figures that cannot easily be drawn using numerical software such as MATLAB or Maple.  For presentations, this can sometimes be accomplished using PowerPoint but more general packages such as xfig or Adobe Illustrator are required to draw more complex figures for papers or detailed presentations. In this RTM, we will illustrate the use of these packages and show how resulting figures can be incorporated into LaTeX, Word, or PowerPoint documents.

This RTM will be of interest to all students and postdocs who will need to construct publication or presentation quality figures at some point during their program or subsequent career.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0r3b208jugnp68m7q1qh10f7eg","2011-09-26 18:55:38",NULL
"1023","26","Experimental design for vector output ODE systems","2011-10-03 16:00:00",NULL,"SAS 4201","Keri Rehm","http://www4.ncsu.edu/~klrehm/index.shtml","NC State",,,"Recent work in experimental design by the CRSC has led to the development of methods for choosing optimal time-points in data collection and parameter selection for estimation in inverse problems that utilize information from the sensitivity matrix or Fisher Information Matrix of an ODE system (CRSC TR08-12, TR09-09, TR10-03, TR10-11). Using a similar framework, we formulate a method to determine which variables should be measured in an experiment in order to maximize the reliability of parameter estimates. Currently we select a subset of parameters to estimate with fixed data sampling times. Initial results when the method is applied to a simple HIV model are presented to illustrate proof of concept.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m9kblsl0pmtcbd73osg3kthpes","2011-09-27 19:43:01",NULL
"1024","26","Maximally Reduced Observers for Linear Time Varying DAEs","2011-10-03 16:30:00",NULL,"SAS 4201","Karen Bobinyec","TBA","NC State",,,"The problem of observer design for descriptor systems, or systems of differential algebraic equations (DAEs) as they are also known, has been studied in the linear time invariant case. However, those studies do not readily extend to general linear time varying descriptor systems. Recently there have been new theoretical results and algorithms for computing completions of DAEs. In this [presentation] we examine the application of these ideas to the computation of reduced order observers for linear time invariant and linear time varying DAEs.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3ps66tnut4gq459oo3h2muf57s","2011-09-27 19:44:37",NULL
"1025","8","Nonnegative Definite Tensors and Neuroimaging","2012-02-29 16:00:00",NULL,"SAS 4201","Lek-Heng Lim","http://galton.uchicago.edu/~lekheng/","University of Chicago",,,"One of the most important classes of matrices is the symmetric positive definite ones. They arise as covariance, density matrix, inner products, Laplacians, Mercer kernels, etc. So what is the equivalent of positive/nonnegative definiteness for higher order symmetric tensors? It turns out that there are two natural but different notions: One is that the homogeneous polynomial associated with the tensor be nonnegative valued while the other is that this polynomial be expressible as a sum of powers of linear forms. These two notions are in fact dual in an appropriate sense.

We show that both notions arise in diffusion MRI and lead to two methods for extracting nerve fibers crossing. We shall see that deciding nonnegative definiteness (either notions) of a higher-order tensor is an NP-hard problem but that due to a happy coincidence the cases relevant to these MRI applications yield readily computable convex problems.

This is joint work with T. Schultz.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jf1hc54bn3usuk4gmh25r34crg","2011-09-28 10:06:58","2012-02-14 10:37:59"
"1026","21","Triangle Lectures in Combinatorics","2011-11-05 10:00:00","2011-11-05 17:00:00","Hanes 120 at UNC Chapel Hill",,,,,"http://www.math.ncsu.edu/TLC/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fv6540roa7vutdp13kp37hhsp8","2011-09-29 10:41:56",NULL
"1027","9","Rolling up with the flow to reduce drag and flutter: A study of broad leaves","2011-10-20 16:00:00",NULL,"Cox 306","Laura Miller","http://www.unc.edu/lam9/pmwiki2/Main/LAM","UNC Chapel Hill, Dept. of Mathematics",,,"Flexible plants, fungi, and sessile animals reconfigure in wind and water to reduce the drag forces acting upon them. In strong winds and floodwaters, leaves roll up into cone shapes that reduce drag compared to rigid objects of similar surface area. Less understood is how a leaf attached to a flexible petiole (leafstalk) will roll-up stably in an unsteady flow. Experiments and numerical simulations using the immersed boundary method are used to describe the unsteady forces acting upon flexible sheets attached to flexible beams. The results from the simplified physical and mathematical models are then compared to measurements taken from broad leaves. The flexible models oscillate in steady and unsteady flow, and average drag forces are higher than those previously reported for flexible beams and sheets tethered to a rigid point. One important distinction between these models and the actual leaves is the ability to roll up into three-dimensional cone shapes. The experiments were repeated for flexible disks cut along a radius rather than rectangular sheets. These disks reconfigured into stable cone shapes similar to leaves. The wakes behind the models and leaves were measured using particle image velocimetry. The structures that reconfigure into cone shapes show a stable pair of vortices that form within the cone. ","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r1q2a023p5ar12m4i4qfnps7oo","2011-09-29 13:28:08","2011-09-29 13:28:59"
"1028","14","Departmental Tea and Cookies","2011-10-05 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6kk07enpgf5av9lrevlr6gloj8","2011-10-03 10:11:15",NULL
"1029","14","Departmental Tea and Cookies","2011-10-10 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3idhap42h737fnq5f8i7m5ml54","2011-10-04 10:32:55",NULL
"1030","21","Reception for Alumni and Friends of the NC State Mathematics Department at the Joint Mathematics Meetings","2012-01-06 17:30:00","2012-01-06 19:30:00","Sheraton Boston Hotel, Clarendon Room (3rd floor)",,,,,"http://www.math.ncsu.edu/events/special_events.php","Alumni, friends, and participants in Mathematics Department programs (such as REU, REU+, IMSM) are invited to meet old friends and hear about events in the Department. 

Hors d'oeuvres and drinks.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/64lejan4gbd1tgmr613e7neths","2011-10-05 10:48:05","2011-11-16 09:55:49"
"1031","23","Presentations Using PowerPoint with LaTeXiT","2011-10-14 15:00:00",NULL,"SAS 4201","Ralph Smith",,"North Carolina State University","Ralph Smith",,"Constructing slides for effective presentations will be critical throughout your career.  Whereas LaTeX-based software such as Beamer can certainly be used for presentations, the incorporation of graphics and movies can be cumbersome, and PowerPoint is required by many employers and funding agencies. In this module, we will show how one can have the best of both worlds by using packages such as LaTeXiT to incorporate mathematics into PowerPoint. This combines the best features of both packages for efficiently constructing mathematics presentations.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r1jqkahc9j0j5a39r3j978qa1s","2011-10-10 09:09:23",NULL
"1032","8","Software design in the LinBox library and prototypes for many-cores architectures ...","2011-10-12 16:00:00",NULL,"SAS 4201","Brice Boyer and Pascal Giorgi",,"Université Joseph Fourier, Grenoble and University Montpellier 2.","Erich Kaltofen",,"LinBox is a powerful C++ linear algebra library. The library is based on genericity by design and adapts to the user inputs. It is structured around a powerful
and simple user interface, which adapts to a multitude of developer algorithms. We will give
some examples of code fragments and actual LinBox performance. LinBox can indeed do state of the art linear algebra on prime fields ; it also provides efficient extension fields and integer, polynomial linear algebra. Then we will also present some recent software design
choices and software engineering decisions. Facing new trends in parallelism, we will finally discuss how
we could generically do parallelism ;  we will give a short overview of the HPAC project funded by the French Research Agency which aims at extending LinBox foundation, and
more generally computer algebra software, to new parallel architectures.

","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uo0uoqtn029p7p2n2fisheu3mk","2011-10-10 13:56:04","2011-10-10 14:18:21"
"1033","8","Tensor Complexes","2011-11-30 16:00:00",NULL,"SAS 4201","Christine Berkesch","http://fds.duke.edu/db/aas/math/faculty/cberkesc","Duke University",,,"The most fundamental complexes of free modules over a commutative ring are the Koszul complex, which is constructed from a vector (i.e., a 1-tensor), and the Eagon--Northcott and the Buchsbaum--Rim complexes,
which are constructed from a matrix (i.e., a 2-tensor). I will discuss a multilinear generalization of these complexes, which we construct from an arbitrary higher tensor. Our construction provides detailed new examples of minimal free resolutions, as well as a unifying view on several well-known examples. As a result, we will encounter a nice class of hyperdeterminantal varieties. This is joint work with Daniel Erman, Manoj Kummini, and Steven Sam.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m0nufsfkt3sefbpi2cf76t56i0","2011-10-15 14:08:24","2011-11-23 14:09:09"
"1034","8","Tensor Seminar:  Matrix Multiplication","2011-10-26 16:00:00",NULL,"SAS 4201","Agnes Szanto",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jdh1m8pfbcsjq2q1cs2nr0hk98","2011-10-15 14:14:32","2011-10-24 11:12:20"
"1035","14","Departmental Tea and Cookies","2011-10-19 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0kqi2v6hu35d78aaqq3t517vjs","2011-10-17 09:54:50",NULL
"1036","23","Optimizing your Conference Experience","2011-10-21 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"Conferences provide an invaluable experience for graduate students and postdocs for a number of reasons: they provide a forum to learn and talk about new mathematics and science, network and meet new people, and possibly meet potential employers.  To optimize the benefit from attending a conference, one needs to plan ahead and be aware of certain strategies.  In this RTM, a panel of faculty and graduate students will discuss strategies for optimizing your conference experience.  Issues to be discussed include: when and how to buy plane tickets, how to find roommates to keep down expenses, how to apply for conference support, how to navigate schedules with multiple sessions, how to effectively network, and how to schedule interviews at conferences such as the Joint AMS Meeting.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c81e2vp3n9r2ook7jgi60o044k","2011-10-17 11:45:27",NULL
"1038","26","Optimal Control Software for Constrained Nonlinear Systems with Delays","2011-10-24 16:00:00",NULL,"SAS 4201","Karmethia Thompson","TBA","NC State",,"TBA","The numerical solution of optimal control problems is important 
in a variety of industries. One of the popular
methods for complex problems is direct transcription. Direct
transcription does not rely on the necessary conditions and
it is easy to incorporate a wide variety of constraints on both
controls and states. Optimal control problems can often involve
delays in the state or the control or both. While some numerical
methods exist for some optimal control problems with delays
they are not direct transcription methods. This paper reports
on progress in developing a general purpose industrial grade
software package to numerically solve complex optimal control
problems with delays and state and control constraints using
direct transcription.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t22kp3vlircd5pgslh7rak5jl8","2011-10-18 18:05:50","2011-10-18 18:06:31"
"1039","22","Field Extensions and the Galois Correspondence","2011-10-26 16:00:00",NULL,"SAS 2102","Jed Mihalisin",,"Meredith College",,"http://www4.ncsu.edu/~nreadin/sum/fall2011/102611.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8fq8sr1mq2hs75p871l6768m9k","2011-10-19 15:51:10",NULL
"1040","6","Direct Transcription Solution of Optimal Control Problems with State and Control Delays","2011-11-22 15:00:00",NULL,"SAS 4201","Steve Campbell","http://www4.ncsu.edu/~slc/","NCSU","NA Seminar",,"The numerical solution of optimal control problems is important in many areas. Often the models for these
problems have delays. Direct transcription is a popular approach for the numerical solution of optimal control problems in industry. However, much less work has been done on the direct transcription solution of optimal control problems with delays. This talk will describe progress and challenges in developing a general purpose industrial grade direct transcription  code that can handle problems with delays. Of special interest will be the more challenging case of control delays.

Collaboration with John Betts and Karmethia Thompson.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a9v1h5ig0f31ectib6jpg5cu1g","2011-10-20 21:35:05","2011-10-21 05:44:33"
"1041","3","Utilizing Ideas from Persistent Homology to Compute Probabilistic Sensor Network Coverage","2012-01-13 16:00:00",NULL,"SAS 4201","Elizabeth Munch","http://www.elizabethmunch.com/math/","Duke",,,"A seminal paper by Ghrist and de Silva gives a homological criterion to check for coverage in a sensor network. We add probabalistic failure of the sensors to this setup and try to compute failure of the criterion. This problem turns out to be #P-hard, so we will look at both a deterministic algorithm which can be used in the case of a small number or a sparse set of sensors, as well as a dynamic algorithm which does not compute the probability of failure, but helps to predict that the set of sensors is getting close to failure.
","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kotbijflci0rup3sbi9fq6u4o8","2011-10-23 14:35:53","2011-11-28 12:46:27"
"1042","14","Departmental Tea and Cookies","2011-10-26 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/l1mh6edt0pj5ubg4qpcdjm87vg","2011-10-24 10:24:25",NULL
"1043","8","Tensor Seminar:  Nuclear Norms","2011-11-02 16:00:00",NULL,"SAS 4201","Seth Sullivant",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vgbu8tgnqdgu469gdd41lnftjs","2011-10-26 11:47:26",NULL
"1045","23","Curriculum Vitae and Research and Teaching Statements","2011-10-28 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"For students and postdocs applying for either academic or nonacademic positions, CV's and research statements are often required as part of the application package.  Additionally, teaching statements are typically required when applying for academic positions.  In this week's RTM, a faculty panel will discuss strategies for writing effective CV's and research and teaching statements.  Examples will be provided during the discussion.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vatok2a1fit6eidlsadf8p20o4","2011-10-26 12:24:06",NULL
"1046","14","Departmental Tea and Cookies","2011-11-02 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pd04970hp728ohfj7vbn08ngus","2011-10-26 17:06:30",NULL
"1047","21","Annual VT Math Competition","2011-10-29 09:00:00",NULL,"SAS 2106",,,,,,"The annual VT math competition will be held on Saturday October 29 from 9:00a.m. to 11:30a.m. in SAS 2106.
 Walk in registration starts at 8:45.

If you teach undergraduate classes or if you know any student who is good in solving math problems and is interested in participate,  please tell him or her in  person  about the competition.


Xiao-Biao Lin","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/g4r4hl4ncc3mg6h82hlnm8da8c","2011-10-27 10:31:31",NULL
"1048","26","Modeling Flash Pyrolysis","2011-10-31 16:00:00",NULL,"SAS 4201","Lucus Van Blaircum",,"NC State",,,,"camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gbn0m6vdltiq74g4of1d1sgq34","2011-10-28 11:30:54",NULL
"1049","4","On a coupled system of incompressible fluid and nonlinear elasticity","2011-11-16 15:00:00",NULL,"SAS 4201","Lorena Bociu","http://www.math.unl.edu/~lbociu2","NC State",,,"The problem under consideration is the free boundary, nonlinear coupling of Navier-Stokes and elasticity. First, I will present a completely new linearization for the coupled system, derived in view of stability analysis. The linearized model reveals the presence of the curvature on the common interface, which demonstrates that the free boundary plays a key role in the analysis of the coupled system, so its influence can not be neglected. Then we prove that the linearized model has unique solution, using a variational approach and some new techniques developed in order to deal with the new boundary terms (which appear as tangential derivatives in a Neumann-type boundary condition).","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/csibkft8hkoj4jnthp22utubfs","2011-10-28 13:29:05","2011-11-03 10:16:45"
"1050","19","Soliton cellular automaton associated with G_2^(1) crystal base","2011-11-18 15:00:00",NULL,"SAS 2235","Evan Wilson",,"NC State Mathematics Graduate Student",,,"A cellular automaton is a dynamical system in which points in a space lattice are assigned discrete values which evolve according to a definite rule. Soliton cellular automata (SCA) are a kind of cellular automata which possess stable configurations analogous to solitons in integrable partial differential equation theory. In joint work with Kailash Misra and Masato Okado, we recently computed combinatorial R-matrix of G_2^(1)-crystals and studied the SCA associated with it. The solitons of length l are identified with elements of A_1^(1)-crystals. The scattering rule for the SCA associated with the G_2^(1) crystal base is identified with the combinatorial R matrix for A_1^(1) crystals.  In this talk we discuss these results, as well as the rewarding experience of living and working in Japan this past summer.","njschwar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4q99tla808g25bjhf80dphdmu4","2011-10-30 20:24:08","2011-10-31 12:09:10"
"1051","23","Job Application Process","2011-11-04 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"We are at that time in the year when students and postdocs
may need to start thinking about the logistics of applying for jobs.  In this week's RTM, a faculty panel will discuss job application resources for both academic and nonacademic positions.  This will include websites and publications advertising positions along with conferences such as the Joint AMS Meeting that link employers and applicants.  We will also discuss issues regarding the logistics associated with the application process.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nv5usch8g9bg65i6004qu5bpp4","2011-11-01 10:15:48",NULL
"1052","23","Final Year Timelines and Strategies","2011-11-11 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"The final year of a Masters, PhD or Postdoctoral program involves a number of deadlines and requirements that are often bewildering. For example, when should one set up their committee, schedule their preliminary exam, apply for jobs, and schedule their defense?  Moreover, how should one budget time for job interviews while finishing their research?  In this RTM, we will discuss a number of these issues to help clarify what needs to be completed during the final year of graduate school or a postdoc program.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6git76p11pamoo4kgbq85qgne0","2011-11-01 10:17:49",NULL
"1053","23","Interview Strategies","2011-11-18 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"What type of presentation should you give and what do you do if you cannot answer a question?  Should you try to negotiate salary or benefits during the initial interview?  Is it appropriate to have your mother call the search committee for any reason? What do you do if your cell phone rings during the interview? What do you do if you are late for the interview and how should you dress?

These questions and others will be discussed during this week's RTM.  This session should be of interest to all students and postdocs presently looking for a job.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/us27qf6hi9sha4hv4ovfus9fp8","2011-11-01 10:19:49",NULL
"1056","8","Tensor Seminar","2011-11-16 16:00:00",NULL,"SAS 4201","Moody Chu",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bo6nkn4kv93lsar740gck1oofg","2011-11-07 08:39:06",NULL
"1057","8","Markov complexity of hypergraphs","2012-03-21 16:00:00",NULL,"SAS 4201","Elizabeth Gross","http://homepages.math.uic.edu/~lizgross/Home.html","University of Illinois-Chicago",,,"The toric ideal of an edge subring of a graph is an object that appears when studying statistical models parameterized by the edges of a graph. There are many results that tell us the same story: we can understand these ideals, if we understand the combinatorics of the underlying graph.  A natural extension is to consider the defining ideal of an edge subring of a hypergraph. In this talk we give some recent results on the toric ideals of hypergraphs, including how to tell if the ideal is generated in a fixed degree. The proposed construction provides the basic step for understanding the combinatorial complexity of these generators, which, in algebraic statistics, provide a Markov basis for the underlying statistical model. This is joint work in progress with Sonja Petrovic.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b2cl4c77o341e1rb3objn3psgo","2011-11-07 08:40:20","2012-02-14 10:45:15"
"1058","8","Secant varieties of Segre-Veronese varieties","2012-03-28 16:00:00",NULL,"SAS 4201","Claudiu Raicu","http://www.math.princeton.edu/~craicu/","Princeton",,,"Secant varieties of Segre and Veronese varieties are classical objects that go back to the Italian school in the nineteen century. Surprisingly, very little is known about their equations. Inspired by experiments related to algebraic statistics, Garcia, Stillman and Sturmfels gave a conjectural description of the generators of the ideal of the secant line variety $Sec(X)$ of a Segre variety $X$. This generalizes the familiar result which states that matrices of rank two are defined by the vanishing of their $3\times 3$ minors. For a Veronese variety $X$, it was known by work of Kanev that the ideal of $Sec(X)$ is generated in degree three by minors of catalecticant matrices. I will describe a technique for studying the equations of the secant varieties of Segre-Veronese varieties, based on the usual representation theoretic approach to this problem. I will explain how this technique applies to show that for $X$ a Segre-Veronese variety, the ideal of $Sec(X)$ is generated in degree three by minors of matrices of flattenings, and to give a description of the decomposition into irreducible representations of the homogeneous coordinate ring of $Sec(X)$. This will recover as special cases the conjecture of Garcia, Stillman and Sturmfels, and the result of Kanev.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6hqjih1jd795mn3uaajl3pqlho","2011-11-07 08:41:46","2012-02-14 10:48:35"
"1059","14","Departmental Tea and Cookies","2011-11-09 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/t2ql3ptrs1l8203u1en0m3vklk","2011-11-07 10:24:42",NULL
"1061","26","Filtering Irregularly Spaced Sparse Observations with a Hierarchical Bayesian Approach AND Characterization of Dispersive Shock Waves in the Magma Equation.","2011-11-14 16:00:00",NULL,"SAS 4201","Kristy Brown and Nick Lowman",,,,,"Kristy Brown will be speaking about Filtering Irregularly Spaced Sparse Observations with a Hierarchical Bayesian Approach. 

Nick Lowman will be speaking about A Characterization of Dispersive Shock Waves in the Magma Equation.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ghtb5ibisdc0g4hibk841u5cgk","2011-11-13 14:51:23",NULL
"1062","14","Departmental Tea and Cookies","2011-11-17 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/skto13r15hf7jr4evi8v4v71p4","2011-11-13 23:36:40","2011-11-13 23:38:03"
"1063","21","The 72nd William Lowell Putnam math competition","2011-12-03 10:00:00","2011-12-03 18:00:00","SAS 2106",,,,,"http://www.math.ncsu.edu/events/special_events.php","The 72nd William Lowell Putnam math competition is fast approaching (12/03).
The Putnam competition has two sessions:  from 10:00am - 1:00 pm (morning session) and from 3:00-6:00 pm
(afternoon session) in SAS2106.  Walk-in registration starts 15 minutes before the competition.  All undergraduate students are eligible to participate.

Student who gets  the  highest score in  NCSU   receives a cash prize.  Top 500 finish nationwide will have  their names published in AMS magazine.   For more information or to obtain practice problems, contact Dr. Lin at xblin@math.ncsu.edu","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e8tntsqse4goslt3ar1c2kt09g","2011-11-16 09:51:24","2011-11-16 09:55:18"
"1064","26","Patient Specific modeling of Head-Up Tilt","2011-11-21 16:00:00",NULL,"SAS 4201","Nakeya Williams",,"NC State",,,"Short term cardiovascular responses to head-up tilt (HUT) experiments involve complex cardiovascular
regulation in order to maintain blood pressure at homeostatic levels. This manuscript presents a patient
specific compartmental model developed to predict dynamic changes in heart rate and arterial blood pressure.
The model contains five compartments representing arteries and veins in the upper and lower body of the
systemic circulation, as well as the left ventricle facilitating pumping of the heart. A physiologically based
sub-model describes gravitational effects on pooling of blood during the HUT, and baroreflex control mechanisms
are included regulating cardiac contractility, peripheral vascular resistance, and vascular tone. Nominal parameters are computed from subject specific data as well as literature estimates. The model uses heart rate
as an input and predicts arterial blood pressure as an output. The model is rendered patient specific via the use
of parameter estimation techniques. This process involves sensitivity analysis, prediction of a subset of identifiable parameters, as well as nonlinear optimization used for estimating the identifiable parameters. Results
show that it is possible to estimate a subset of model parameters that allows prediction of observed changes
in arterial blood pressure. Furthermore, the model adequately predicts arterial and venous blood pressures, as
well as cardiac output in compartments for which data are not available.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0132c2atlhpq51p65103ala8jg","2011-11-17 10:09:41",NULL
"1065","26",,"2011-11-21 16:30:00",NULL,"SAS 4201","Eugenia Bakunova",,"NC State",,,,"camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ehnof7f89kijn5mto7naljg6jk","2011-11-17 10:10:12",NULL
"1066","21","Kwangil Koh Lecture on Mathematics in Our Time","2012-04-16 16:30:00",NULL,"SAS 2203","Donald Saari","http://math.uci.edu/~dsaari/","Distinguished Professor of Mathematics and Economics, University of California, Irvine",,"http://www.math.ncsu.edu/events/Saari.php","This public lecture is the first in an annual series honoring our late colleague Kwangil Koh. The goal of the Koh lectures is to communicate the importance of mathematics and its impact on science, technology and society. 

There will be a reception from 4.00 to 4.30 in SAS Hall second floor lobby.

Mathematics and the mystery of dark matter

Even after spending billions of dollars on experiments, we have not been able to find that mysterious thing hiding in the heavens called ""dark matter."" Sounds ominous! But what is it? Why do we believe it is important? As described in this expository lecture, mathematics is shedding significant new light on dark matter. ","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nkga2uevn4hcgncs8kmkpvtk9s","2011-11-17 11:14:42","2012-03-27 10:32:32"
"1067","3","Curve neighborhoods of Schubert varieties","2012-02-10 16:00:00",NULL,"SAS 4201","Leonardo Mihalcea","https://bearspace.baylor.edu/Leonardo_Mihalcea/www/index.htm","Virginia Tech",,,"If X is a Schubert variety in a flag manifold, its curve
neighborhood is defined to be the union of the rational curves of a
fixed degree passing through X. It turns out that this is also a
Schubert variety, and I will explain how to identify it explicitly in
terms of the combinatorics of the Weyl group and of the associated
(nil-)Hecke product. If time remains, I will also show how this yields
a new, natural proof of the Chevalley formula in the quantum
cohomology of flag manifolds. This is joint work with A. Buch and uses
previous results joint with A. Buch, P.E. Chaput and N. Perrin.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ad5hf2lqg6genjrmjvido7fl98","2011-11-17 20:03:35","2012-02-06 07:37:44"
"1068","26","Application to Carbon Sequestration","2011-11-28 16:00:00",NULL,"SAS 4201","Kathy Varga",,"NC State",,,"Abstract: Carbon Capture and Storage (CCS) involves capturing carbon dioxide released from industrial processes and storing, or sequestering, it to keep it out of the atmosphere at least for centuries. Deep saline aquifers are promising storage sites for this purpose. As the CO2 flows through the permeable rock, some of it becomes trapped in the pore spaces. This process is known as residual trapping. We investigate a model for the flow of CO2 in a saline aquifer and study how the modeling of residual trapping affects the solutions.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vh9enf08074lia9q0t1rfc1l2k","2011-11-27 13:09:00",NULL
"1069","26","Faraday Waves on Surfactant Covered Thin Films","2011-11-28 16:30:00",NULL,"SAS 4201","Lake Bookman",,"NC State",,,"TBA","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/haqqskqec4dpmeqeskphu1n808","2011-11-27 13:09:30","2011-11-27 13:28:58"
"1070","14","Departmental Tea and Cookies","2011-11-30 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/56cai61p4hn18c6b942cu4kk6g","2011-11-27 22:21:22",NULL
"1071","3","Invariant subalgebras of affine vertex algebras","2012-03-16 16:00:00",NULL,"SAS 4201","Andrew Linshaw",,"Brandeis University",,,"Given a simple, finite-dimensional Lie algebra g, let V_k(g) denote the universal affine vertex algebra at level k. We prove that for an arbitrary reductive group G of automorphisms of V_k(g), the invariant subalgebra V_k(g)^G is strongly finitely generated for generic values of k.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6j887tpbjhnb477lbdn7mnvqq0","2011-11-28 12:49:03","2012-03-09 20:41:26"
"1072","9","Modelling genetic control of insect pests","2011-12-09 15:30:00",NULL,"Cox Hall, Room 306","Nina Alphey",,"Dept. of Zoology, University of Oxford",,,"Modelling genetic control of insect pests

Dr Nina Alphey

Mathematical Ecology Research Group, 
Department of Zoology, University of Oxford, United Kingdom

E-mail nina.alphey@zoo.ox.ac.uk

The sterile insect technique (SIT) is an area-wide pest control method that reduces pest populations by releasing mass-reared sterile insects which compete for mates with wild insects.  Genetic RIDL technology (Release of Insects carrying a Dominant Lethal)* is a proposed modification of the technique, releasing insects that are homozygous for a repressible dominant lethal genetic construct rather than being sterilized by irradiation.  I will present research using mathematical modelling to explore questions about this genetic approach.

Using the arbovirus dengue as an example, we combine vector population dynamics and epidemiological models to explore the effect of a programme of RIDL releases on disease transmission.  We use these to derive a preliminary estimate of the potential cost-effectiveness of vector control by applying estimates of the costs of SIT.  Through mathematical modelling, we predict that this genetic control strategy could eliminate dengue from a human community in a timescale within one year, and at 
lower cost than the direct and indirect costs of disease that would be averted by doing so.

As with any new insect control method, questions arise about potential resistance.  Hypothetical resistance to the lethal mechanism is a potential threat to RIDL strategiesâ effectiveness against disease vectors or agricultural pests.  Using population genetic and population dynamic models, we assess the circumstances under which monogenic 
biochemically-based resistance could have a significant impact on the effectiveness of releases for population control.  We assume that released insects would be homozygous susceptible to the lethal genetic 
construct and therefore releases would have a built-in element of resistance dilution.  We find that this effect could prevent or limit the spread of resistance to RIDL constructs.

*RIDL is a registered trademark of Oxitec Limited, UK.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/li60tafcuafsvsecqhbq1e0mac","2011-12-03 08:59:29","2011-12-03 09:02:56"
"1073","14","Spring Departmental Meeting","2012-01-09 16:00:00",NULL,"SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/k42bcvfc05dgio556v95u4b0r4","2011-12-13 15:10:00",NULL
"1074","14","Departmental Tea and Cookies","2012-01-09 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/je9sebclnjfpa6p8lad3bd5uvo","2011-12-13 15:10:40",NULL
"1076","8","Splitting full matrix algebras over algebraic number fields","2012-04-25 16:00:00",NULL,"SAS 4201","Lajos Rónyai","http://www.sztaki.hu/~ronyai/","Computer and Automation Institute,  Hungarian Academy of Sciences","Agnes Szanto",,"Let K be an algebraic number field of degree d and 
discriminant D over the rationals. Let A be an associative algebra over K 
given by structure constants such that A is isomorphic to the algebra M_n(K) 
of n by n matrices over K for some positive integer n. 
Suppose that d, n and D are bounded. Then an isomorphism of A with M_n(K) 
can be constructed by a polynomial time ff-algorithm. (An ff-algorithm is 
a deterministic procedure which is allowed to call oracles for factoring 
integers and factoring univariate polynomials over finite fields.)

In addition to computational representation theory, the algorithm 
can be applied to parametrization problems of algebraic geometry, 
and to computations with n-Selmer groups of elliptic curves.

The method leads to a polynomial time ff-algorithm to compute 
isomorphisms of central simple algebras of bounded degree over K.
This is joint work with Gabor Ivanyos, Adam Lelkes, and Josef Schicho.

Related manuscript can be found at:
http://arxiv.org/abs/1106.6191","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3rrtj939f4u6icno24prmvjuf8","2011-12-17 07:45:44","2012-04-18 09:29:33"
"1077","2","Superintegrabilty, special functions and orthogonal polynomials","2011-01-13 15:00:00",NULL,"SAS 4201","Sarah Post","http://www.crm.umontreal.ca/~post/Welcome.html","Centre de Recherches Mathematiques, Montreal",,,"Superintegrable systems are Hamiltonian systems which admit more integrals of motion than degrees of freedom. Among the remarkable properties of such systems is their deep connection with special functions and orthogonal polynomials.  I will discuss some recent advances in the theory of superintegrable systems emphasizing this connection.  The first result concerns the exact-solvability of wave functions and a method which uses known recurrence relations for hypergeometric functions to construct integrals of motion [1]. This method was applied to prove the superintegrability of a  system with reflections [2] associated with a new family of orthogonal polynomials that are eigenfunctions of a differential-difference operator [3]. The second result concerns the realization of representations of symmetry algebras generated by the integrals of motion in terms of orthogonal polynomials, including a model [4] based on a two-variable generalization of the Wilson polynomials by Tratnik [5]. Finally, if there is time, I will discuss a Hamiltonian system of Drach [6] that was recently proved superintegrable and is the first known case of a real, quantum superintegrable system which does not allow separation of variables in any coordinate system [7].

[1]  Kalnins,  Kress and  Miller  (2011)
[2] Post, Vinet  Zhedanov  (2011)
[3] Vinet and Zhedanov  (2011)
[4] Kalnins, Miler and Post  (2011)
[5] Tratnik (1991), Geronimo and Illiev (2010)
[6] Drach  (1935)
[7] Post and  Winternitz  (2011)","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/glj1nkko3anumn4dah9qiog554","2011-12-20 08:47:47",NULL
"1078","2","Superintegrabilty, special functions and orthogonal polynomials","2012-01-13 15:00:00",NULL,"SAS 4201","Sarah Post","http://www.crm.umontreal.ca/~post/Welcome.html"," Centre de Recherches Mathematiques, Montreal",,,"Superintegrable systems are Hamiltonian systems which admit more integrals of motion than degrees of freedom. Among the remarkable properties of such systems is their deep connection with special functions and orthogonal polynomials.  I will discuss some recent advances in the theory of superintegrable systems emphasizing this connection.  The first result concerns the exact-solvability of wave functions and a method which uses known recurrence relations for hypergeometric functions to construct integrals of motion [1]. This method was applied to prove the superintegrability of a  system with reflections [2] associated with a new family of orthogonal polynomials that are eigenfunctions of a differential-difference operator [3]. The second result concerns the realization of representations of symmetry algebras generated by the integrals of motion in terms of orthogonal polynomials, including a model [4] based on a two-variable generalization of the Wilson polynomials by Tratnik [5]. Finally, if there is time, I will discuss a Hamiltonian system of Drach [6] that was recently proved superintegrable and is the first known case of a real, quantum superintegrable system which does not allow separation of variables in any coordinate system [7].

[1]  Kalnins,  Kress and  Miller  (2011)
[2] Post, Vinet  Zhedanov  (2011)
[3] Vinet and Zhedanov  (2011)
[4] Kalnins, Miler and Post  (2011)
[5] Tratnik (1991), Geronimo and Illiev (2010)
[6] Drach  (1935)
[7] Post and  Winternitz  (2011)","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lk2p9u1pjr7e4vgfi6vfb2h7og","2011-12-21 08:19:16",NULL
"1079","2","Numerical solutions to inverse problems","2012-01-12 16:00:00",NULL,"SAS 4201","Julianne Chung","http://omega.uta.edu/~chungj/","Department of Mathematics, UT-Arlington",,,"In many physical systems, measurements can only be obtained on the exterior of an object (e.g., the human body or the earth's crust), and the goal is to estimate the internal structures.  In other systems, signals measured from machines (e.g., cameras) are distorted, and the aim is to recover the original input signal.  These are natural examples of inverse problems that arise in fields such as medical imaging, astronomy, geophysics, and molecular biology.  The difficulty with ill-posed inverse problems is that small errors may result in significant errors in the computed solutions, so regularization must be used to compute stable solution approximations. 

In this talk, we investigate regularization methods for linear and nonlinear inverse problems.  We describe recent advances in spectral filtering approaches and hybrid iterative methods for regularization of linear inverse problems.  Regularization for nonlinear Poisson based models, such as those arising from digital tomosynthesis reconstruction, is significantly more challenging, but accurate reconstruction is important in many real-life applications.  Reconstruction algorithms will be discussed, and numerical experiments illustrate the effectiveness and efficiency of the proposed methods.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/s14qf9n5ptf59r2u55f7uau0ek","2011-12-21 08:24:33","2011-12-21 14:47:06"
"1080","2","Hyperbolic models for flocking behavior","2012-01-20 15:00:00",NULL,"SAS 4201","Sebastien Motsch","http://seb-motsch.com/","Center for Scientific Computation and Mathematical Modeling, University of Maryland",,,"In many biological systems, we observe the emergence of self-organized dynamics (flock of birds, school of fish, aggregation of bacteria...). To understand these phenomenon, many ""microscopic models"" have been proposed. Those particles models aim at reproducing the patterns observed in nature.  In this talk, we will be interested in the large scale behavior of these models. The derivation of ""macroscopic models"" will lead to hyperbolic models.  In contrast to classical physical systems, these hyperbolic systems are not conservative and therefore analytical and numerical studies are very challenging.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kako31dr98dk4i81sk5huj94do","2011-12-21 08:28:09",NULL
"1081","2","Efficient algorithm for electronic structure calculations","2012-01-09 15:00:00",NULL,"SAS 4201","Jianfeng Lu","http://www.cims.nyu.edu/~jianfeng/","Courant Institute of Mathematical Sciences, NYU",,,"Electronic structure theories, in particular Kohn-Sham density functional theory, are widely used in computational chemistry and material sciences nowadays. The computational cost using conventional algorithms is however expensive which limits the application to relative small systems. This calls for development of efficient algorithms to extend the first principle calculations to larger system. In this talk, we will discuss some recent progress in efficient algorithms for Kohn-Sham density functional theory. We will focus on the choice of accurate and efficient discretization for Kohn-Sham density functional theory.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qr4e38mck9q2t5g3cfcv6csueg","2011-12-21 08:31:39","2012-01-03 10:46:55"
"1082","2","Internal imaging of graphs and applications to urban sensing","2012-01-10 16:00:00",NULL,"SAS 4201","Michael Robinson","http://www.math.upenn.edu/~robim/","Department of Mathematics, University of Pennsylvania",,,"How can one determine the shape of one's surroundings by listening to ambient signal sources?  Traditional remote-sensing ideas place strong requirements on the topology and geometry of the sensorium in order to exploit linearity, often by using integral transform methods.  While useful for understanding the propagation of low frequency waves, in practice they are difficult to use.  I will motivate a change in focus away from global, spectral methods to local, sheaf methods.  New results following from this change in focus suggest a two-stage method for recovering first topology and then geometry.  These theoretical results supply a new family of practical algorithms for addressing a class of distributed sensing problems.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v3r0iu3ch8asb41dspdkdofeu8","2011-12-21 08:34:02","2011-12-21 10:31:43"
"1083","2","Symbolic-numeric methods for systems of polynomial equations","2012-01-17 16:00:00",NULL,"SAS 4201","Jonathan Hauenstein","http://www.nd.edu/~jhauenst/","Department of Mathematics, Texas A&M University",,,"Many symbolic and numerical methods for solving polynomial systems arising in a wide range of applications in science, economics, and engineering have been developed.  In general, symbolic methods provide certified results but are often inherently serial with numerical methods providing reliable heuristic results but are often parallelizable.  Some goals for symbolic-numeric methods are to provide certification of numerical methods, and increase parallelizability and computational efficiency of symbolic methods.  This talk will explore using symbolic-numerical methods for counting the number of real solutions to a system of polynomial equations, lattice base reduction techniques for computing generators of an ideal, and verification of theoretical results relating K3 surfaces and Hilbert's sums of squares cones.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7aa6siobkt5ihfpbcm8j6qgarg","2011-12-21 08:39:24","2011-12-21 14:45:56"
"1085","14","Departmental Tea and Cookies","2012-01-20 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/o9qmoc3o6fv8t85j4sm0vrnido","2011-12-21 11:40:19",NULL
"1087","14","Departmental Tea and Cookies","2012-01-10 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vi9vpsbhej6kfdpf8vmgud20n8","2011-12-26 11:06:30",NULL
"1088","14","Departmental Tea and Cookies","2012-01-17 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0cog12ag1qvvv9danhrlrd6c2g","2012-01-02 10:05:15",NULL
"1089","14","Departmental Tea and Cookies","2012-01-12 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1ru114v125a42j0o5svvkcpm5c","2012-01-03 13:17:30",NULL
"1090","14","Departmental Tea and Cookies","2012-01-13 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2nqtmj4p1qom00a52m6lj0ki20","2012-01-03 13:22:16",NULL
"1091","3","Advances in Geometric Invariant Theory","2012-04-13 16:00:00",NULL,"SAS 4201","Amassa Fauntleroy","http://www4.ncsu.edu/~amassa/","NC State",,,"The geometric invariant theory pioneered by Mumford has been very successful in helping to solve classification problems in algebraic geometry. The highlight has been the construction of moduli spaces for algebraic curves. For some time researchers have wanted to apply these ideas to objects when the natural groups that arise are not reductive (i.e. finite or having a compact form). Recent work of Kirwan and Doran has now made this possible in a large class of important cases. We discuss the essence of their breakthrough.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tgl9ultqunf5uljdjhp81ifjnc","2012-01-06 14:38:54","2012-04-09 13:04:52"
"1092","6","Comparing the Laplace Transform and the Parareal Algorithms","2012-02-21 15:00:00",NULL,"SAS 4201","Craig Douglas","http://www.mgnet.org/~douglas/","Wyoming","NA Seminar",,"Both the Laplace Transform and the Parareal family of algorithms promise to provide completely parallel in time and space computational results. Given a random problem it is unclear which algorithm will run faster.

In this talk, we will provide the following:
    •    Define the algorithms in question, including more specific details than usual.
    •    Define interesting parallel environments, some of which do not exist yet.
    •    Demonstrate several computational environments in which one of the algorithms can be expected to be faster than the other algorithm, including a compact 6th order finite difference scheme of a different sort..","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/23jenv9t3ksccjni7rrui5bkm4","2012-01-07 11:28:00","2012-02-09 16:50:27"
"1093","4","Using a Hodkin-Huxley type model to understand afferent nervous response to changes in blood pressure","2012-01-25 15:00:00",NULL,"SAS 4201","Mette Olufsen","www4.ncsu.edu/~msolufse/","NCSU",,,,"xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qj4tbfl8accaausv638ut2q2so","2012-01-09 08:26:32","2012-01-20 12:47:56"
"1094","8","An effective method to stop the refiner in Caboara's dynamic algorithm","2012-03-14 16:00:00",NULL,"SAS 4201","John Perry","http://www.math.usm.edu/perry/","University of Southern Mississippi",,,"Dynamic Buchberger algorithms were first described in 1993 by Caboara and, separately, by Gritzmann and Sturmfels. These algorithms search for a Groebner basis by modifying the term ordering during the computation. In many cases, the result is a smaller basis with fewer monomials.

Caboara's algorithm modifies the ordering by refining it; this maintains compatibility with past choices.  After a certain point, however, refining provides no benefit, and incurs a significant cost. Caboara simply stopped refining at a predetermined point, but more effective techniques exist. We present two new techniques that not only stop the refiner when it is clearly useless, but restart it only when there is a high certainty that the ordering can be refined.  Experimental evidence indicates the effectiveness of this technique.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p4qit1h6i5lndarf2plv2lbdlo","2012-01-10 17:09:16","2012-03-07 13:46:49"
"1095","6","Random Unstructured Meshes via Maximal Poisson-disk Sampling","2012-04-03 16:00:00",NULL,"Burlington Labs","Mohamed Ebeida",,"Sandia National Labs","NE Seminar",,"We describe several new approaches to generating random point clouds for triangular (simplicial) meshes and dual Voronoi cell meshes in d-dimensional spaces. We utilize the Poisson-disk sampling process to produce provably-good tessellations, with quality bounds similar to deterministic Delaunay refinement methods. In contrast to other meshing methods, our point cloud strictly adheres to a given distribution function selected based on the input geometry and physics. We show the impact of Poisson-disk sampling on reducing the complexity and improving the robustness of Delaunay/Voronoi meshing algorithms using uniform and non-uniform distribution results. We will also discuss how to utilize these sampling techniques to achieve better estimations of probability of failure for uncertainty quantification problems. Several application examples will be presented to demonstrate the efficiency of our methods.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2gb1qanm2ffb3ns6ukn4nvktic","2012-01-10 19:47:37","2012-01-11 15:47:41"
"1096","4","Capturing intermittent and low-frequency variability in high-dimensional data through nonlinear Laplacian spectral analysis","2012-03-30 15:00:00",NULL,"SAS 4201","Dimitris Giannakis",,"Courant Institute of Mathematical Sciences","John Harlim",,"Nonlinear Laplacian spectral analysis (NLSA) is a method for spatiotemporal analysis of high-dimensional data, which represents temporal patterns via orthonormal basis functions on the nonlinear data manifold. Through the use of such basis functions (determined by means of graph Laplace-Beltrami eigenfunction algorithms), NLSA captures intermittency, rare events, and other nonlinear dynamical features which are not accessible through classical linear approaches such as singular spectrum analysis. We discuss applications of NLSA to detection of decadal and intermittent variability in the North Pacific sector of comprehensive climate models, and dimension reduction of a chaotic low-order model of the atmosphere.

","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n309ip57dpdi82s983aie7epbs","2012-01-12 13:51:40","2012-03-26 10:25:48"
"1097","4","Fundamental Limitations of Polynomial Chaos for Uncertainty Quantification in systems with intermittency","2012-04-03 15:00:00",NULL,"SAS 4201","Michal Branicki",,"Courant Institute of Mathematical Sciences","John Harlim",,"I will discuss the suitability of truncated Polynomial Chaos
Expansions (PCE) and truncated Gram-Charlier Expansions (GrChE) as possible methods for uncertainty quantification (UQ) in nonlinear systems with intermittency and positive Lyapunov exponents.  Based on a simple, statistically exactly solvable non-linear and non-Gaussian test model, I will show in detail that methods exploiting truncated
spectral expansions, be it PCE or GrChE, have significant limitations for uncertainty quantification in systems with intermittent instabilities or parametric uncertainties in the damping. Intermittency and fat-tailed probability densities are hallmark features of the inertial and dissipation ranges of turbulence and it turns out that in such important dynamical regimes PCE performs, at best, similarly to the vastly simpler Gaussian moment closure technique. Moreover, I will  show that  the on-realizability of the GrChE approximations is linked to the onset of intermittency in the dynamics and it is frequently accompanied by an erroneous  blow-up of the second-order statistics at short times.","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/572ggrco1uclt7n3obi95nr2h0","2012-01-12 13:58:52","2012-03-26 10:33:53"
"1100","6","An efficient multi-level method for radiative transport equation with applications to optical imaging","2012-03-13 15:00:00",NULL,"SAS 4201","Hongkai Zhao",,"UC Irvine","Zhilin LI",,"We present an efficient algorithm for solving radiative transport equation (RTE) which is a golden standard for modeling photon migration in tissue. RTE is proposed in phase space which includes both spatial and angular variables. Moreover, the scattering term coupled particle transport in all directions together. We design a multi-level algorithm in both space and angle combined with appropriate discretization. Our algorithm can deal with multiple scattering and forward peaking effectively. Convergence and error estimate analysis will be shown. Applications to optical imaging will be provided.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/73gumtbdam41g5oa2he0i0po78","2012-01-15 11:06:10","2012-02-24 13:41:50"
"1101","8","Tensor Seminar:  Catelecticants","2012-01-25 16:00:00",NULL,"SAS 4201","Agnes Szanto",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/md8h0h2v7abc63eujsqd6g1huo","2012-01-17 11:20:11","2012-01-23 14:42:46"
"1102","8","Tensor Seminar:  Tensors and Algebraic Geometry","2012-02-08 16:00:00",NULL,"SAS 4201","Seth Sullivant",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/23abksc4aje28r8hg08po3u6mo","2012-01-17 11:22:08","2012-01-26 14:42:47"
"1103","8","Telescopers for Rational and Algebraic Functions via Residues","2012-02-22 16:00:00",NULL,"SAS 4201","Shaoshi Chen","http://www.risc.jku.at/home/schen","NC State",,,"We show that the problem of constructing telescopers for functions of m
variables is equivalent to the problem of constructing telescopers for
algebraic functions of m -1 variables and present a new algorithm to
construct telescopers for algebraic functions of two variables.
These considerations are based on analyzing the residues of the input.
According to experiments, the resulting algorithm for rational functions
of three variables is faster than known algorithms, at least in some examples
of combinatorial interest. The algorithm for algebraic functions implies a new
bound on the order of the telescopers.   ","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vb7si5pb81a003n8fcjjv6ovlc","2012-01-17 11:23:56","2012-02-14 10:37:57"
"1104","21","American Mathematics Competitions","2012-02-22 15:15:00",NULL,"SAS 11022",,,,,"http://www.math.ncsu.edu/selfreg/amc.html","http://www.math.ncsu.edu/selfreg/amc.html","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/d9nhkn1mojs6de18abr0a59ut8","2012-01-18 11:10:27",NULL
"1105","22","The shape of space","2012-01-25 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/012512.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0v9u9r35jg1frafbtg8ki32d88","2012-01-18 13:59:10","2012-01-18 14:00:31"
"1109","4","Climate Variability, When Data Fail Us","2012-04-18 15:00:00",NULL,"SAS 4201","Juan Restrepo","http://math.arizona.edu/~restrepo/","Uncertainty Quantification Group, Math Department, University of Arizona","John Harlim",,"
The fundamental task in climate variability research is to eke out structure from climate signals. Ideally we want a causal connection between a physical process and the structure of the signal. Sometimes we have to settle for a correlation between these. The challenge is that the data is often poorly constrained and/or sparse. Even though many data gathering campaigns are taking place or are being planned, the very high dimensional state space of the system makes the prospects of climate variability
analysis from data alone  impractical. Progress in the analysis is possible by the use of models and data. Data assimilation is one such strategy. In this talk we will describe the methodology, illustrate some of its challenges, and highlight some of the ways our group has proposed to improving the methodology.","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m8e9nmhj5ejqoq9rk4iebqsp70","2012-01-24 17:53:51","2012-04-11 13:33:09"
"1110","2","A Flexible Stochastic Collocation Algorithm on Arbitrary Nodes via Interpolation","2012-01-31 16:00:00",NULL,"SAS 4201","Dongbin Xiu","http://www.math.purdue.edu/~dxiu/","Purdue University",,,"Stochastic collocation methods have become the dominating methods for uncertainty quantification and stochastic computing of large and complex systems. Though the idea has been explored in the past, its popularity is largely due to the recent advance of employing high-order nodes such as sparse grids. These nodes allow one to conduct UQ simulations with high accuracy and efficiency. 

The critical issue is, without any doubt, the standing challenge of the ""curse-of-dimensionality"".  For practical systems with large number of random inputs, the number of nodes for stochastic collocation method can grow fast and render the method computationally prohibitive. Such kind of growth is especially severe when the nodal construction is structured, e.g., tensor grids, sparse grids, etc. One way to alleviate the difficulty is to employ adaptive approach, where the nodes are added only in the region that is needed. To this end, it is highly desirable to design stochastic collocation methods that work with arbitrary number of nodes on arbitrary locations. Another strong motivation is the practical restriction one may face. In many cases one can not conduct simulations at the desired nodes. 

In this work we present an algorithm that allows one to construct high-order polynomial responses based on stochastic collocation on arbitrary nodes. The method is based on constructing a ""correct"" polynomial space so that multi-dimensional polynomial interpolation can be constructed for any data. We present its rigorous mathematical framework, its practical implementation details, and its applications in high dimensions.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ad5c6dcofu32mm6jc0hnt69i7o","2012-01-25 08:10:29",NULL
"1111","6","Large-Scale Iterative Solvers for Linear and Nonlinear Systems","2012-04-10 15:00:00",NULL,"SAS 4201","Van Emden Henson",,"Lawrence Livermore National Laboratory","NA Seminar",,"Increasingly, modern science depends on fully coupled multiphysics modeling that must be carried out on problems of extraordinarily large scales. Complicated interdependent physical phenomena are routinely modeled with grid discretizations of numerous physical quantities on grids with hundreds of millions or billions of points. Furthermore, at each time step in an evolutionary physical problem the discretization leads to systems of hundreds of millions or billions of linear or nonlinear equations.
 
For problems on this scale, having scalable solvers is essential. Scalability exists in two areas:  algorithmic scalability implies that as the problem size grows the number of iterations required for a solution remains relatively constant, while parallel scalability implies that as the problem size grows the time to solution remains relatively constant. Department of Energy scientists, along with collaborators in industry and academia have spent much of the past twenty years discovering and developing methods to achieve both types of scalability.
 
In this survey talk we describe the need for scalable algorithms and give a superficial look at some approaches to achieve scalability.  We then focus principally on algebraic multigrid, or AMG (mostly used as a preconditioner for a Krylov method), describing some of the basic properties and principles of AMG, as well as some of the challenges that must be surmounted to achieve both algorithmic and parallel scalability of AMG.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2tblh064a3ircse3kk8p8gk7lg","2012-01-25 16:14:19","2012-04-04 19:27:46"
"1112","2","Polynomial System Solving over the Reals: Algorithms, Complexity, Implementations and Applications","2012-02-03 15:00:00",NULL,"SAS 4201","Mohab Safey El Din","http://www-polsys.lip6.fr/~safey/","Universite Pierre et Marie Curie (Paris 6)",,,"Solving non-linear algebraic systems is one of the important challenges in scientific computing and symbolic computation.  In several areas of engineering sciences, algebraic systems encode geometric conditions on variables taking their values over the reals. Thus, most of the time, one aims to obtain some informations on the real solution set of polynomial systems. The resolution of these problems often has a complexity which is exponential in the number of variables.  Moreover, symbolic computation and computer algebra techniques provide a suitable framework to handle the non-linear algebraic nature of the considered problems and to ensure the numerical quality of the output. 

In this context, the issues are to identify useful specifications for the end-users, to develop exact algorithms, to control their complexity suitably, and to implement efficient software. Our contributions rely on recent geometric ideas that lead to practically efficient algorithms whose complexity meet the best known complexity bounds. Our approach is based on reducing polynomial system solving to global optimization problems and a fruitful interplay between real algebraic geometry, algebraic geometry and commutative algebra.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9qg7bnc9ccdc5r0a24tomqmubg","2012-01-26 08:36:57",NULL
"1113","23","Feedback Regarding the Joint Mathematics Meetings","2012-01-27 15:00:00",NULL,"SAS 4201","Student Panel",,"North Carolina State University","Ralph Smith",,"The Joint Mathematics Meetings (JMM) provide an important opportunity to give presentations, attend talks, and interview with potential employers.  Before the break, we had an RTM that focused on preparation for the JMM.  In this RTM, a panel of attendees will discuss their experience and provide insights that will enhance the experience for students attending future JMM.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0519a9dh8r0rs0rgqesgq2da04","2012-01-26 11:28:37",NULL
"1114","23","Post-Interview Topics","2012-02-10 15:00:00",NULL,"SAS 4201","Departmental Faculty",,"North Carolina State University","Ralph Smith",,"You've had one or more job interviews and you may wonder what to do now.  For example, should you negotiate if you receive an offer?  Is it ever okay to accept more than one offer?  What do you do if you don't hear back from an interview?

These questions and others will be discussed during this week's RTM.  This session should be of interest to all students and postdocs presently looking for a job.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tkuu6ur3n3o1htsvamvjp5u69s","2012-01-26 11:30:39",NULL
"1115","14","Departmental Tea and Cookies","2012-01-31 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/g2d51rj4chbnfrqs2ifik30j6k","2012-01-26 14:01:03",NULL
"1117","8","Tensor Seminar:  Catelecticants Continued","2012-02-01 16:00:00",NULL,"SAS 4201","Agnes Szanto",,"NCSU",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bv965ce205u3hmm4n9vkcmt3do","2012-01-26 14:43:42",NULL
"1118","8","Tensor Seminar:  Representation theory for tensor rank","2012-02-15 16:00:00",NULL,"SAS 4201","Alex Fink",,"NCSU",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3ilfbi399e4oan7crqms5sceak","2012-01-26 14:45:25",NULL
"1119","4","Global weak solution for kinetic models of active swimming and passive suspensions","2012-02-08 15:00:00",NULL,"SAS 4201","Xiuqing Chen",,"Beijing University of Posts & Telecommunications; Duke Physics & Mathematics","Alina Chertock",,"We investigate two kinetic models for active suspensions of rod-like and ellipsoidal particles, and passive suspensions of dumbbell beads dimmers, which couple a Fokker-Planck equation to the incompressible Navier-Stokes or Stokes equation. By applying cut-off techniques in the approximate problems and using compactness argument, we prove the existence of the global weak solutions with finite (relative) entropy for the two and three dimensional models. For the second model, we establish a new compact embedding theorem of weighted spaces which is the key in the compactness argument. 
","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rm900rtaje55udfdag2lonprbk","2012-01-27 11:49:56",NULL
"1120","14","Departmental Tea and Cookies","2012-02-03 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/k4k9lngecnd3r3jd781jh845vs","2012-01-30 09:11:46",NULL
"1121","21","Categorification of Quantum Groups and Representation Theory","2012-04-21 08:00:00","2012-04-22 17:00:00","1102 SAS Hall, NCSU",,,,,"http://www4.ncsu.edu/~misra/SELie/index2.htm",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/brkqs72iibu4rje2lgutavqsj8","2012-01-30 11:41:18",NULL
"1122","22","Can you say something about solutions without finding them?","2012-02-01 16:00:00",NULL,"SAS 2102","Hoon Hong",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/020112.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t5e53n0d1i9d1sgf9civpl755s","2012-02-01 10:25:05",NULL
"1123","22","Regular polytopes and tessellations:  Why life is more interesting in low dimension","2012-02-08 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/020812.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m94dgthfcakldttu6qb46b8t9c","2012-02-01 10:28:12",NULL
"1124","22","TBA","2012-02-15 16:00:00",NULL,"SAS 2102","Sandra Paur",,"NC State",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l4oqc85htb7ics5bm2ljuub9o0","2012-02-01 10:29:06",NULL
"1125","22","The right treatment at the right time: an introduction to personalized medicine","2012-04-11 16:00:00",NULL,"SAS 2102","Eric Laber",,"NC State Statistics",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/041112.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qls22k00hoc2pgglq56aanm4jk","2012-02-01 10:30:06","2012-04-09 13:23:40"
"1126","22","Alan Turing's work on Voice Encryption","2012-04-18 16:00:00",NULL,"SAS 2102","Craig Bauer",,"NSA/York College",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eol1jgj96o2ufbqe85r3qlio4g","2012-02-01 10:31:01",NULL
"1127","27","Triangle Lectures in Combinatorics","2012-02-11 09:15:00","2012-02-11 17:00:00","Physics Building, Room 128, Duke University",,,,,"http://www.math.ncsu.edu/TLC/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c9v3vj8htdu9ttb2n63qgqi35o","2012-02-01 12:30:19",NULL
"1128","9","Modeling and simulation of fluid flow around the bell of the upside-down jellyfish, Cassiopea xamachana","2012-03-29 16:00:00",NULL,"Cox 306","Christina Hamlet",,"NC State, Mathematics",,,"We examine the fluid dynamics of feeding and particle exchange in the upside down jellyfish (Cassiopea sp.) using computational fluid dynamics and experiments with live animals. To solve the Navier-Stokes equations coupled to an immersed, flexible boundary representing the bell of a jellyfish we use a classic version of the immersed boundary method. The oral arms of the jellyfish which protrude over the bell and alter the flow are represented by a homogeneous porous structure.

We compare our results to the flow produced by the live organism using particle image velocimetry (PIV) and dye visualization. The effect of the oral arms on vortex formation and on volumetric flow rates are also numerically simulated across a range of Reynolds numbers, porosities, and bell kinematics.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kf0mga1g3c7rfth47f1752ogbo","2012-02-01 14:55:05",NULL
"1129","1","Using symmetry groups to understand puzzles  from the social sciences","2012-04-17 16:00:00",NULL,"SAS 1102","Donald Saari","http://math.uci.edu/~dsaari","University of California, Irvine","Steve Schecter","http://www.math.ncsu.edu/events/saari_coll.pdf","Mathematicians are often surprised by the large number of fascinating puzzles that come from the social and behavioral sciences.  This talk will introduce some of these puzzles and show how answers can be found with the aid of mathematical symmetries.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/3k8hk63tk4tfjhqhvqkgemnqa4","2012-02-03 12:14:14","2012-04-02 14:46:33"
"1130","14","Departmental Tea and Cookies","2012-02-08 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9a406iklullffgb06rif7n925k","2012-02-06 09:31:45",NULL
"1131","24","MGSA Annual Cookie Contest","2012-02-13 11:00:00",NULL,"SAS 4104",,,,,,"Happy February! 

Valentine's Day is approaching, and MGSA is hosting its annual Cookie Contest on Monday, February 13. Anyone can enter the contest by bringing your favorite dessert recipe (it doesn't have to be cookies.) There will be cash prize for the winners. The contest will take place on Monday 2/13 from 11 am to 1 pm in SAS 4th floor lounge. Please bring your dessert to the lounge by 11 am, or you can drop them off with Alyssa or Colleen in SAS 4125 by 10:30 am. There will also be a candy jar contest (you get to keep the jar full of candy if you guess correctly!) I will send out a reminder email next week. Hope everyone will come participate! ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ufnmrs3845m7fvltr3es4rssrc","2012-02-06 10:54:59",NULL
"1132","3","A Detailed Look at How the Nazi Enigma Ciphers Were Broken Along with the Historical Background and Impact","2012-04-20 16:00:00",NULL,"SAS 4201","Craig Bauer","http://faculty.ycp.edu/~cbauer/","NSA/York College",,,"The talk begins with a demonstration of an Enigma cipher machine and an explanation of how it works. Then the manner in which a small team of Polish mathematicians cracked these ciphers is given in complete mathematical detail (mostly abstract algebra). The important contributions made by the French, British, and even some Germans (!) is covered. Historical context is provided throughout and the impact the decipherments made in shortening the war and saving lives is presented. A tremendous amount will be packed into this lecture, making the pace of a blitzkrieg look leisurely by comparison, but a complete set of notes will be provided to all attendees for future reference!

Speaker bio:  
Craig Bauer earned his PhD in mathematics from N. C. State in 1999. He considers N.C. State to be one of the best choices he ever made and remembers many of his professors with great fondness. Craig is presently on a leave of absence from York College of Pennsylvania (where he's an associate professor of mathematics) to serve as the Scholar-in-Residence at the National Security Agency's Center for Cryptologic History. He also serves as the editor-in-chief of Cryptologia, a quarterly journal devoted to all aspects of cryptology.","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/voim9i88v80kjsbd4do2sj0tsk","2012-02-07 16:50:09","2012-02-07 16:50:57"
"1133","8","Closed form solutions of linear difference equations in terms of second order linear difference equations","2012-03-16 15:00:00",NULL,"SAS 1102 NOTE UNUSUAL PLACE AND TIME","Yongjae Cha","http://www.risc.jku.at/home/ycha","RISC, Johannes Kepler University, Linz, Austria","Michael Singer",,"In this talk we show how to give a closed form solution for third
order difference operators in terms of solutions of second order
operators. This work is an extension of previous results on finding
closed form solutions of recurrence equations and a counterpart to
existing results on differential operators. As motivation and
application for this work, we discuss the problem of proving
positivity of sequences given merely in terms of their defining
recurrence relation. The main advantage of the present approach to
earlier methods attacking the same problem is that our algorithm
provides human-readable and verifiable, i.e., certified proofs.
(A joint work with Veronika Pillwein)
","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jtmebotivaunvajkv413eug8ao","2012-02-09 10:46:43","2012-02-29 14:57:04"
"1134","4","Chemotaxis: PDE-based modeling, analysis and numerics","2012-03-21 15:00:00",NULL,"SAS 4201","Alexander Kurganov","http://www.math.tulane.edu/~kurganov","Department of Mathematics Tulane University","Alina Chertock",,"I will first give a brief review of several PDE-based chemotaxis models. In the main part of my talk, I will present a new chemotaxis model, which can be viewed as a regularization of the classical Patlak-Keller-Segel (PKS)
system. Our modification is based on a fundamental physical property of the chemotactic flux—its boundedness. This means that the cell velocity is proportional to the magnitude of the chemoattractant gradient only when the latter is small, while when the chemoattractant gradient tends to infinity the cell velocity saturates. Unlike the original PKS system, the solutions of the modified model do not blow up in either finite or infinite time in any number of spatial dimensions, thus making it possible to use
bounded spiky steady states to model cell aggregation. I will show both local and global existence results, as well as the existence and stability of one-dimensional spiky steady states.

These analytical results will be verified numerically using a second-order positivity preserving central-upwind scheme. I will then demonstrate that solutions of the two-dimensional model with nonlinear saturated chemotactic
flux typically develop very complicated spiky structures.

If time permits, I will also present an extension of the discussed chemotaxis models to the two-species case.

The talk is based on joint works with A. Chertock (NC State), M. Lukacova-Medvid'ova (Univ of Mainz), X. Wang (Tulane) and Y. Wu (Capital Normal Univ)
","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rrfcinl83g3ssb4fv8dhe4reis","2012-02-10 13:46:15","2012-03-16 14:40:01"
"1135","4","Redundant Coordinates and Variational Integrators","2012-04-25 15:00:00",NULL,"SAS 4201","Dmitry Zenkov",,"NC State University",,,"Variational integrators are discrete dynamical systems obtained by discretizing a variational principle of continuous-time mechanics. Among their features are structure-preservation and ability to capture the statistical properties of complex systems well even if the time step is relatively large. Construction of variational integrators on manifolds that are not Lie groups is a nontrivial and not yet completely understood problem. We discuss an approach to this problem that utilizes redundant coordinates, thus avoiding issues with multiple charts and artificial singularities.
","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m37vl8cbms03n1gp39kptjio0c","2012-02-10 13:49:41","2012-04-20 12:35:20"
"1136","26","Nonsmooth Optimization Method and the Elastic Contact Problem","2012-02-13 16:00:00",NULL,"SAS 4201","Sarah King",,"NC State",,,"We present a nonsmooth optimization method for solving the elastic contact problem. The Signorini contact problem is a variational problem that minimizes the elastic deformation energy subject to the contact inequality, i.e., the normal displacement at a given point of the boundary bounded above by an obstacle function. The Coulomb friction problem is a minimization of the deformable energy with a friction term at the boundary. We then develop an effective numerical optimization method using the semi-smooth Newton method for the both variational problems. The method is of the form of Primal-Dual active set methods for the Lagrange multiplier
methods. We approximate these variational formulations with a multi-moment scheme based on Adini's elements which involves the use of the function values as well as the gradient values at nodes. The Primal-Dual active set method is then applied to these approximations. Finally we combine the solutions to the Signorini and Coulomb friction problems to solve the full contact problem.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m4uhefpojd9sovi6vf4137bmoc","2012-02-12 12:39:03","2012-02-12 17:49:00"
"1137","14","Departmental Tea and Cookies","2012-02-16 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hpqplgkdn67k5jqnaijqu2fq08","2012-02-13 10:10:23",NULL
"1139","4","Limit cycles for a family of Lotka-Volterra systems.","2012-03-01 15:00:00",NULL,"SAS 4201","Adam Mahdi",,"NC State University",,"http://www4.ncsu.edu/~amahdi/",,"xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vlmjtnq5qpc0riutg0ckova8mk","2012-02-14 12:44:25","2012-02-24 20:15:28"
"1140","2","Introduction to Radar Imaging","2012-02-23 16:00:00",NULL,"SAS 4201","Margaret Cheney","http://homepages.rpi.edu/~cheney/","Rensselaer Polytechnic Institute",,,"Radar imaging is a technology that has been developed, very successfully, within the engineering community during the last 50 years.  Radar systems on satellites now make beautiful images of regions of our earth and of other planets such as Venus.  One of the key components of this impressive technology is mathematics, and many of the open problems are mathematical ones.

This lecture will explain, from first principles, some of the basics of radar and the mathematics involved in producing high-resolution radar images.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/icf7q88ipa7hpgv3sh3mm3dd24","2012-02-16 13:49:42",NULL
"1141","4","Stability and Centers in the Moon-Rand Systems","2012-03-16 15:00:00",NULL,"SAS 4201","Douglas Shafer",,"UNC Charlotte","Adam  Mahdi",,"In the mid-80's F.C. Moon and R.H. Rand examined a method for control of flexible space structures using feedback control of certain elements of the stiffness matrix. The method leads to nonlinear control equations, and ultimately systems of nonlinear ordinary differential equations in R^3 with an equilibrium at the origin for which the linear part of the system has a pair of purely imaginary eigenvalues for all values of the parameters. Moon and Rand examined one family of such systems and found a sufficient condition for asymptotic stability of the equilibrium and by numerical means evidence for existence of asymptotically stable periodic oscillation. We use this family as a platform for a discussion of methods for examining stability and center conditions for systems of ODE's in R^2 and R^n whose linear part at an equilibrium has a pair of purely imaginary eigenvalues, using center manifold theory for n>2. We treat both theoretical and computational aspects of the problem, and return to the Moon-Rand amilies to illustrate the methods. ","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ov1h8v71tkt1sbtukc0efudoj0","2012-02-17 10:33:34","2012-02-17 10:36:01"
"1142","14","Departmental Tea and Cookies","2012-02-23 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/o3kipdg0tnor9q7sa1lfutrsus","2012-02-20 10:54:58",NULL
"1143","22","The abc conjecture","2012-02-22 16:00:00",NULL,"SAS 2102","Alina Duca",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/022212.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3srcn7bjikuqoavr05r6ccm430","2012-02-20 11:20:46",NULL
"1144","22","The mechanics of tissue dynamics","2012-02-29 16:00:00",NULL,"SAS 2102","Sharon Lubkin",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/022912.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0q9tkmjhntesc0b7ltgk7n76ik","2012-02-20 11:32:05",NULL
"1145","6","Sampling in and out of equilibrium when the tails matter","2012-03-20 15:00:00",NULL,"SAS 4201","Jonathan Weare",,"University of Chicago","John Harlim",,"Analyzing and simulation rare events in stochastic process is important in many areas. For example, in the context of weather and climate, prediction can be dramatically hampered by unlikely, but important transitions in the underlying system. The past decade or so has seen dramatic improvements in our ability to simulate and analyze these events.
So far this progress has come mostly in the contexts of Chemistry and Computer Science but
rare event ideas seem ripe for application in geophysical contexts. I will survey a bit of my work in rare event simulation generally as well as show some preliminary work toward geophysical applications.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mpo4nrd0t87nl1d7u8507ef8fo","2012-02-21 09:00:28","2012-03-16 05:56:39"
"1146","30","Weakly Nonlinear Boundary Value Problems with Impulse","2012-02-22 14:00:00",NULL,"SAS 4201","Dan Maroncelli","http://www4.ncsu.edu/~dmmaronc/","NC State Mathematics Graduate Student",,"http://www4.ncsu.edu/~rsivapr/GSAPS/Dan1.pdf","First talk in the Graduate Student Analysis and Probability Seminar series for the semester of Spring 2012. 

Talks from interested Graduate Students working in closely related topics are invited.","rsivapr","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d62vu1rp9tn5g3jbnmohvg4ttc","2012-02-21 21:13:17",NULL
"1147","3","Polyhedral models for generalized associahedra via Coxeter elements","2012-03-30 16:00:00",NULL,"SAS 4201","Salvatore Stella",,"Northeastern","Nathan Reading",,"Motivated by the theory of cluster algebras, S. Fomin and A. Zelevinsky have associated to each finite type root system a simple convex polytope called a generalized associahedron.  It turns out that this purely combinatorial gadget encodes much information on the associated cluster, algebra making it an interesting object to study.

I will describe, after recalling the basic definitions, a family of geometric realizations of these polytopes, parametrized by orientations of the corresponding Dynkin diagram.  I will also show that this construction agrees with the one given by C. Hohlweg, C. Lange and H. Thomas in the setup of Cambrian fans developed by N. Reading and D. Speyer.","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eb12cv2saii37tt7jsuhpf8lm4","2012-02-23 09:25:46","2012-03-16 15:39:19"
"1148","3","Surprising shapes of free resolutions","2012-04-27 16:00:00",NULL,"SAS 4201","Christine Berkesch",,"Duke",,,"Boij and Soederberg offered an important shift in perspective when they
suggested that graded free resolutions over a polynomial ring were more
easily understood when viewed ``up to scalar multiple."" More precisely,
they conjectured the existence of a simplicial structure on a cone given
by the numerics of these resolutions. This was subsequently proven by
Eisenbud and Schreyer, which in turn provided a proof of the long-standing
Herzog--Huneke--Srinivasan Multiplicity Conjecture.

We will discuss analogous results for free resolutions over local rings.
Over a regular local ring and their hypersurface rings, we completely
classify the possible shapes of these resolutions. This illustrates the
existence of free resolutions whose Betti numbers behave in surprisingly
pathological ways. This is joint work with Daniel Erman, Manoj Kummini,
and Steven V Sam.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6c8usp773indcd859vrkkq9mtg","2012-02-23 19:42:24",NULL
"1149","3","Soliton cellular automaton associated with G_2^(1) crystal base","2012-04-04 15:00:00",NULL,"SAS 1102 (Please note unusual place and time)","Evan Wilson",,"NC State Mathematics Graduate Student",,,"A cellular automaton is a dynamical system in which points in a space lattice are assigned discrete values which evolve according to a definite rule. Soliton cellular automata (SCA) are a kind of cellular automata which possess stable configurations analogous to solitons in integrable partial differential equation theory. In joint work with Kailash Misra and Masato Okado, we recently computed combinatorial R-matrix of G_2^(1)-crystals and studied the SCA associated with it. The solitons of length l are identified with elements of A_1^(1)-crystals. The scattering rule for the SCA associated with the G_2^(1) crystal base is identified with the combinatorial R matrix for A_1^(1) crystals.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2ggf8g2bcnaniqgne38rionp9s","2012-02-25 18:12:01","2012-04-01 19:58:07"
"1150","14","Departmental Tea and Cookies","2012-02-29 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/o4krfaf7tv5tjdlk2s7pv19mfc","2012-02-27 09:44:18",NULL
"1151","8","Fast Computation of Smith Forms of Sparse  Matrices over Local Rings","2012-04-04 16:00:00",NULL,"SAS 4201","Mark Giesbrecht","http://www.cs.uwaterloo.ca/~mwg/","Cheriton School of Computer Science, University of Waterloo","Erich Kaltofen",,"The diagonalization of matrices known as Smith Normal Form
has many applications in mathematics and engineering.  Computation of
the Smith form of matrices over local rings, such as the integers
modulo a prime power, or univariate polynomials modulo a power of an
irreducible, are of particular interest.  While fast algorithms for
computing the Smith form of dense matrices are now well-established,
exploiting sparsity in the input would allow us to address much larger
problems.  In this talk we present new algorithms for computing Smith
forms of sparse matrices over local rings which exploit sparsity.
Some of these algorithm provide provable improvements in complexity
over the best previously known methods.

This is a joint work with Mustafa Elsheikh, Andy Novocin and B. David Saunders.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mn069kn2ta1a013doci3dgm3to","2012-02-27 14:05:29","2012-03-28 21:56:15"
"1152","14","Departmental Tea and Cookies","2012-03-15 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kv3vpl0advnq8udultpb602bjo","2012-03-07 15:10:21",NULL
"1154","22","Platonic Solids","2012-03-14 16:00:00",NULL,"SAS 2102","Tom Lada",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/031412.pdf","A result from classical geometry states that there are exactly 5 Platonic solids.  After discussing the requisite definitions, we will use elementary combinatorial topology to prove the result.
","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jphe633m760vqmjhval1fi5pmo","2012-03-13 09:24:48",NULL
"1155","22","Why don't we (usually) faint when we stand up?","2012-03-21 16:00:00",NULL,"SAS 2102","Mette Olufsen",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/032112.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2egc81rkm0j20kum3dqr0uue4c","2012-03-13 09:26:04",NULL
"1156","22","Making waves: Solitons and their applications","2012-03-28 16:00:00",NULL,"SAS 2102","Terrance Pendleton",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/spring2012/032812.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1o4thg8g251mjmdc39nguf8c4o","2012-03-13 09:27:14","2012-03-26 09:52:33"
"1157","3","Lie algebraic construction of Jack symmetric functions","2012-03-21 14:30:00",NULL,"SAS 1102 (Please note unusual place and time)","Naihuan Jing","http://www4.ncsu.edu/~jing/","NC State",,,"Jack symmetric functions are generalizations of Schur symmetric functions. Special cases of Jack symmetric functions appear as spherical functions of classical symmetric spaces, just as Schur functions are characters of the general linear group. Rectangular Jack functions also appear as singular vectors for the Fock space representation of the Virasoro algebra. In this talk we will generalize this idea to give a new characterization of Jack polynomials via generalized Laplace-Beltrami operators, and then construct all Jack functions by vertex operators. As applications of the new constructions, we will give new iterative formula, determinant formula and analytic formula for Jack functions, and also verify new cases of Stanley's conjecture on the generalized Littlewood-Richardson coefficients.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4gm0fje1aa21ci6usdr9a49b2c","2012-03-16 09:51:13","2012-03-21 09:44:14"
"1158","26","Predicting Arterial Flow and Pressure Dynamics","2012-03-19 16:00:00",NULL,"SAS 4201","Christina Battista",,"NC State",,,"Abstract: This talk will derive the 1D fluid dynamics model for the prediction of blood flow, pressure, and vessel area in systemic arteries.  The model is derived from the the Reynolds Transport Theorem and the Navier-Stokes equations for an incompressible fluid through a network of tapered cylindrical vessels.  ","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/s9sat44oo85qfv5e5030mjirkg","2012-03-18 10:37:44",NULL
"1159","21","The World of Exploding Dots","2012-03-23 14:00:00",NULL,"SAS 1102","James Tanton",,,,,"Let's explore the mysteries and wonders of a simple dots and boxes
""machine"" that unites all of grade school arithmetic, all of highschool
polynomial algebra, elements of undergraduate calculus, and some current
unsolved research questions in one fell and amazing swoop. Exploding
dots shall astound!","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u4p9r1f8pkhoudr9em2aaouprg","2012-03-19 10:44:45",NULL
"1160","21","Mathematica in Education and Research","2012-03-20 16:00:00",NULL,"450 Riddick Hall","Michael Chastain",,"Wolfram Research, Inc.",,,"No matter if your specialty is in a STEM, business and economics, or liberal arts field, you won't want to miss this discussion about the latest advances in
Mathematica and their impact on your teaching and workflow.
","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/4id5agsjk7ukrd9c4guhl5rjjs","2012-03-19 13:00:01",NULL
"1161","9","Mathematical models in substance use and addiction","2012-04-19 16:00:00",NULL,"Cox 306","Georgiy Bobashev",,"RTI International",,,"Studies of substance use and addiction are fascinating not only because the topic is so rich but because almost everyone can relate to them. What does it take to get addicted to food, drugs, sex, internet? Why we are getting used to certain things after repeated exposure but get bored of the others? Is addiction a disease or lack of willpower? How long does it take to get addicted? 

These questions still don't have definite answers, and scientists are now turning to modeling in order to understand, prevent and treat addiction. From a modeling perspective substance use has features of both infectious  and chronic diseases and thus approaches and techniques could be borrowed from each of the subject areas. However the challenge is to put them together in a meaningful way. 

I will present a range of models from neurobiology to policy that illustrate the problems and challenges that the field is experiencing. The variety of modeling techniques covers statistical models, system dynamics, discrete event, and agent-based models.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kvro1cn3590ejdhqn1k7k0nd3g","2012-03-19 14:58:13",NULL
"1162","9","Zooplankton, Water Residence Time and Basic Science at the US Army Research Office","2012-04-26 16:00:00",NULL,"Cox 306","Virginia Pasour",,"US Army Research Laboratory, RTP",,,"While plankton have often been thought to behave as passive tracers, completely at the mercy of the hydrodynamic flow, the commonness of plankton patches, as well as field studies showing evidence of microorganism movement against the bulk (or mean) flow, suggests that individual plankton behavior such as vertical/horizontal migration may dominate at smaller scales. In natural water bodies such as embayments and estuaries, macrophytes can have a significant and complex effect on water flow and can greatly complicate physical/biological interactions. Using a two-dimensional hydrodynamic model to create flows in an idealized channel with macrophytes modeled as a porous layer, we model the channel under a number of different macrophyte regimes, with the eventual goal of studying how the interaction of plankton migration behaviors and macrophyte structures affect biological retention. 

The second part of the talk will consist of information about funding opportunities through the U.S. Army Research Office, in particular the relatively new Biomathematics Program.
","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dor147rd03rrq98me9o8ec6f80","2012-03-19 14:59:26","2012-04-25 12:52:24"
"1163","14","Departmental Tea and Cookies","2012-03-21 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e8l02th00oa8t7ib8aq9dhp5a8","2012-03-21 10:54:51",NULL
"1164","26","Modeling Red Blood Cell and Iron Dynamics in Patients with Chronic Kidney Disease","2012-03-26 16:00:00",NULL,"SAS 4201","Dustin Kapraun",,"NC State",,,"Chronic kidney disease causes a decline in kidney function and leads to End Stage Renal Disease (ESRD), a diagnosis which is characterized by the need for regular dialysis treatments. Patients in ESRD also have deficiencies of erythropoietin (EPO), a hormone produced in the kidneys which stimulates red blood cell (RBC) production. In order to counteract symptoms of anemia, ESRD patients often receive intravenous EPO and iron treatments. In this talk, we will develop a PDE model for RBC dynamics in ESRD patients and briefly discuss its coupling with an ODE model for iron dynamics. We then discuss a finite element approach for solving the PDEs and provide evidence that our finite element implementation will converge to a correct solution. The work to be discussed is a collaborative effort involving Karen Bliss (recent NCSU Math PhD graduate and current faculty member at West Point), as well as NCSU Math faculty H.T. Banks and H.T. Tran. The talk is designed to be accessible to first- and second-year graduate students with some exposure to modeling principles and PDEs.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1vep0goppn2p0dik0vlplonvm8","2012-03-24 13:34:33",NULL
"1165","4","Hopf Bifurcation in Symmetric Networks of van der Pol Oscillators with Ferromagnetic Core: Twisted Equivariant Degree Approach","2012-04-20 15:00:00",NULL,"SAS 2235","Z. Balanov",,"University of Texas at Dallas",,,"The van der Pol oscillator (VDPO) consists of an LCR-contour and a negative feedback loop which can be implemented on the basis of a triode. The corresponding second order (autonomous) van der Pol equation is the simplest nonlinear mathematical model widely used in electrical engineering. In practice, one is usually dealing with networks of VDPOs coupled symmetrically. Studying the impact of symmetries of a system to the actual dynamics (in particular, symmetric properties and minimal number of periodic regimes) constitutes a problem of great importance and complexity which can be traced back to the classical 16-th Hilbert problem.

Periodic solutions to symmetric autonomous systems very often are studied via the so-called equivariant Hopf bifurcation in a parameterized system (i.e. a phenomenon occurring when the parameter crosses some ""critical"" value causing a change of stability of the ""trivial solution"", which results in appearance of small amplitude non-constant periodic solutions near the trivial one). The commonly used method (M. Golubitsky et al.) is based on the equivariant singularity theory (EST) combined with a Lyapunov-Schmidt reduction or Central Manifold Theorem. However, this method cannot be applied if the system in question is not smooth enough and/or the phase space does not admit a local linear structure.

On the other hand, if an inductance element in the van der Pol oscillator contains a ferromagnetic core, the ferromagnetic material can introduce a hysteresis relation between the magnetic induction and magnetic field. In many cases (for example, in the presence of the ferroresonance phenomenon), the hysteresis effect cannot be neglected. As a matter of fact, systems with hysteresis almost always are non-smooth and the corresponding phase spaces do not admit a local linear structure. Therefore, the EST based method cannot be applied to them. In my talk, I will show how an alternative method based on the usage of the new invariant – twisted equivariant degree (introduced by Z. Balanov and W. Krawcewicz) -- can be effectively applied to symmetric networks of VDPO with hysteresis. In particular, a direct link between physics, topology, algebra and analysis underlying the VDPOs will be established.

This talk is based on a joint work with W. Krawcewicz, D. Rachinskii and A. Zhezherun. ","xblin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/upbmctkggll8uhhsceff9dov7s","2012-03-25 21:09:54","2012-04-19 13:53:57"
"1166","14","Departmental Tea and Cookies","2012-03-28 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dgjauacv7tqtqcpr63jd544vek","2012-03-26 09:29:40",NULL
"1167","26","High Dimensional Model Representation","2012-04-02 16:00:00",NULL,"SAS 4201","Mami Tonoe",,"NC State",,,"High Dimensional Model Representation (HDMR) is a technique used to represent high dimensional functions efficiently. When the input-output relationship in a physical system can not explicitly be shown, or when the cost of each simulation is too high, the computational cost of full state analysis for a n-dimensional variable space scales exponentially. In the context of Nuclear Engineering, the high dimension involves n > 100 input variables. Fortunately, in nature, it is argued that the physical system with rationally chosen variables likely do not have significant contributions from the high order correlations terms. Under the assumption that only low-order correlation in the input variables have significant impact on the output, HDMR is shown to reduce the computational cost dramatically for high dimensional systems.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mvt5dss0lqpmg39fjtgif952ts","2012-03-27 10:06:32",NULL
"1168","7","Parameter estimation in second-order continuous time linear autoregressions","2012-04-04 14:00:00",NULL,"SAS 4201","Sergey Lototsky","http://www-bcf.usc.edu/~lototsky/","University of Southern California","Min Kang",,"For the one-dimensional Ornstein-Uhlenbeck process, asymptotic behavior of the maximum likelihood estimator (MLE) of the drift depends on the sign of the unknown parameter, and there are three different distributions possible in the limit. The objective of the talk is to discuss a similar problem when the underlying  deterministic equation is second-order in time and there are two parameters to estimate.  In this case, the asymptotic behavior of the MLE depends on the roots of the corresponding characteristic equation. All in all, there are nine cases to consider, and some of the results are rather unexpected. This is a joint work with Ning Lin.
","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b8ekbton77hu9o24kpl82lr3h4","2012-03-28 14:11:30","2012-04-02 11:20:36"
"1169","26","UQ of Domain Decomposition in Simulation of Interacting Particles","2012-04-02 16:30:00",NULL,"SAS 4201","James Nance",,"NC State",,,,"camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/brt1ne28bdruqgc317dlcmb7e8","2012-03-29 16:09:09",NULL
"1170","14","Departmental Tea and Cookies","2012-04-04 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nl09p6apb17ft5gi6gjfe0l1bc","2012-04-02 10:22:35",NULL
"1171","14","Awards Day Reception Tea and Cookies","2012-04-23 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jev86bt5jdmi3mbii2ctau6pmk","2012-04-03 10:53:10",NULL
"1172","14","Awards Day Ceremony","2012-04-23 16:00:00",NULL,"SAS 1102",,,,,,"Our Annual Awards Day Ceremony will be held on Monday, April 23rd, 4:00 pm in SAS 1102, with a reception at 3:30 pm in SAS 4104.  Please plan to attend and honor our outstanding undergraduate and graduate students.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/h986idgn7ujk4nfgg9jbv01dl8","2012-04-03 10:54:09",NULL
"1173","12","Undergraduate workshop at SAMSI","2012-05-14 08:00:00","2012-05-18 17:00:00",,,,,,"http://www.samsi.info/workshop/interdisciplinary-workshop-undergraduate-students-may-14-18-2012","Interdisciplinary workshop on dynamics and statistics for undergraduate students, May 14-18, 2012.

This week-long workshop will provide an introduction to the field of uncertainty quantification (UQ) to students from the mathematical and statistical sciences. Undergraduates majoring in engineering and physical sciences are also invited to apply. This hands-on workshop will introduce the students to a variety of statistical and mathematical techniques used to make forecasts and/or to provide control in systems where uncertainty uncertainties are unavoidable. The workshop will extend concepts learned in undergraduate linear algebra, statistics, and differential equations courses; no prior experience with UQ is necessary or expected.

The students will make use of Bayesian concepts to develop controllers for  specific stochastic dynamical systems. Working in teams, the students will be implementing simple variational, Kalman, and Monte Carlo techniques and compare these in their ability to track data-driven dynamics. The students will work in groups of three under the supervision of SAMSI researchers, visitors and postdocs.

The deadline to apply is April 20, 2012.

More information is available at http://www.samsi.info/UGM12

The organizers:

Cammey Cole Manning (Meredith College)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p39ki0lcb4bp1gccpmj4v2ndo0","2012-04-03 12:01:25",NULL
"1174","8","Tensor Seminar:  Tensors in Differential Geometry","2012-04-11 16:00:00",NULL,"SAS 4201","Irina Kogan","http://www4.ncsu.edu/~iakogan/","NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ip1a86vjj1edsa774ck6nejv7o","2012-04-03 14:49:26",NULL
"1175","14","Departmental Tea and Cookies","2012-04-10 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lqimar83cpv2unasi84agj9ocs","2012-04-04 12:43:30",NULL
"1176","15","SIAM Guest Speaker","2012-04-10 13:15:00",NULL,"SAS 3282","Van Henson",,"Lawrence Livermore National Laboratory","SIAM Student Chapter",,"Dr. Henson will talk about his research and his experiences working for a national laboratory.  As always, food and drink will be provided.  Come by and bring a friend!","klrehm","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/d1n7202r2u8onlghgcmbssi780","2012-04-05 10:19:54",NULL
"1177","26","Observer construction for systems of DAEs using completions.","2012-04-09 16:00:00",NULL,"SAS 4201","Karen Bobinyec",,"NC State",,,"Systems of differential algebraic equations (DAEs) describe many physical systems of interest in control theory. Constructing observers for systems of DAEs is an active area of control theory research because a general design method is not currently accepted. Our approach for constructing observers combines recent results from numerically computed completions of DAE systems with observers designed for systems of ordinary differential equations. This presentation reviews the development of our approach and presents results for a linear time-varying example system and for a linear time-invariant example system.","camccar2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3dpf2a818n2r8vkdvgimsemnmg","2012-04-09 08:38:57",NULL
"1178","14","Saari Reception","2012-04-16 16:00:00",NULL,"SAS Second Floor Lobby",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n3o6b5giva85s2b4hcgd7ln990","2012-04-16 09:29:15",NULL
"1179","14","Departmental Tea and Cookies","2012-04-17 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/49200loearjn3r6pu82552k8q0","2012-04-16 09:36:01",NULL
"1180","22","Undergraduate Research talks","2012-04-25 16:00:00",NULL,"SAS 2102","Jeff Gory, Tim Wessler, Kimberly Rochester, Jeff Fowler",,"NC State Undergrads",,"http://www4.ncsu.edu/~nreadin/sum",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h989nlukr26qcofo903c6n1ul8","2012-04-23 20:50:51",NULL
"1181","14","Dr. Steve Campbell Retirement Reception","2012-05-07 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sat8v3olmv1veudre7r708r794","2012-05-07 11:48:51",NULL
"1182","4","Nucleation, Propagation, and Control of Magnetic Solitons","2012-10-31 15:00:00",NULL,"SAS 4201","Mark Hoefer","http://www4.ncsu.edu/~mahoefer","NC State",NULL,NULL,"The theory of magnetic solitary waves or solitons inmagnetic materials with uniaxial anisotropy was developed in theseventies and eighties by Kosevich, Ivanov, and Kovalev but has, untilnow, escaped experimental observation.  This talk will present recentobservations of nontopological, magnetic droplet solitons by JohanAkermans group in Stockholm, enabled by the use of the spin transfertorque effect in a nanometer scale point contact device.  Motivated bythese observations, this talk will demonstrate the existence andstability of a two-parameter family of two-dimensional magneticdroplet solitons and their relation to experiment.  Solitonperturbation theory will be used to describe the effects of physicalperturbations including damping, spin torque, and an external magneticfield.  Novel behavior including time-periodic breather states, thecounterintuitive acceleration of the droplet due to damping, andcontrolling the droplets frequency and speed with a spatially uniformexternal magnetic field will be described.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ijfhiho3bu24vpgenb3tgberu4","2012-06-07 22:28:05","2012-10-16 15:44:18"
"1183","4","Rigorous justification of the modulation approximation to the full water wave problem","2012-11-14 15:00:00",NULL,"SAS 4201","Nathan Totz","http://fds.duke.edu/db/aas/math/ntotz","Duke",NULL,NULL,"In this joint work with Sijue Wu (U. Mich.), we consider solutions to the 2D inviscid infinite depth water wave problem neglecting surface tension which are to leading order wave packets with small amplitude and slow spatial decay that are balanced.  Multiscale calculations to suppress secular growth on $O(epsilon^-2)$ time scales formally suggest that such solutions have modulations $B$ that evolve on those time scales according to a focusing cubic NLS equation.  Justifying this rigorously is a real problem, since standard existence results do not yield solutions which exist for long enough to see the NLS dynamics.  Nonetheless, given initial data within $O(epsilon^3/2)$ of such a wave packet in $L^2$ Sobolev space, we show that there exists a unique solution to the water wave problem which remains within $O(epsilon^3/2)$ to the formal approximation for times of order $O(epsilon^-2)$.  This is done by using a formulation of the evolution equations for the water wave problem developed by Sijue Wu with no quadratic nonlinearity.  If time permits, we will also discuss progress in the analogous problem in the 3D setting.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6717mrmfp79i5oj7fd3tlns8ms","2012-06-08 14:27:51","2012-10-31 13:58:29"
"1184","4","Settling and Rising in Density Stratified Fluids: Analysis and Experiments","2012-11-07 15:00:00",NULL,"SAS 4201","Shilpa M Khatri","http://www.unc.edu/~khatri/","UNC Chapel Hill",NULL,NULL,"The fluid dynamics of particles settling and droplets rising in density stratified fluids is vital to understanding the effect of stratification in marine settings. Whether studying particles settling or droplets rising, similar small scale dynamics are observed. An example of settling is provided by marine snow aggregates, particles composed of organic and inorganic matter, which play a major role in the carbon cycle. Most of these macroscopic particles are extremely porous, allowing diffusion of a stratifying agent (heat or salt) from the ambient fluid to affect the density and therefore the settling dynamics of these particles. As a first step towards understanding these dynamics, we study the case of a single spherical particle settling in water stratified by salt, focussing on effects of porosity and salt diffusion. For linear stratification in viscosity dominated regimes, an explicit solution for the spheres position in time is derived. For more general ambient fluid stratification, the spheres position can be solved for numerically, under the asymptotic assumptions about the typical time scales of diffusion and settling.  As well, a discussion about the competing effects of entrainment and diffusion will be included. A parametric study of the settling behaviors and preliminary comparisons with experiments will be presented. For the case of rising droplets, which occur in the environment as oil seeps and jets in the ocean, we study a single oil droplet in a similar setup as the porous particles. Preliminary results will be presented, and similarities and differences with the previous case of settling particles will be discussed.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r2q8t8b4elvotj08j4cuu2mis0","2012-06-11 05:02:55","2012-10-28 17:51:37"
"1185","4","Toward efficient parallel in time methods for PDEs","2012-10-17 15:00:00",NULL,"SAS 4201","Matthew Emmett","http://www.unc.edu/~mwemmett/","UNC Chapel Hill",NULL,NULL,"A new method for the parallelization of numerical methods forpartial differential equations (PDEs) in the temporal direction ispresented.  The method is iterative with each iteration consistingof deferred correction sweeps performed alternately on fine andcoarse space-time discretizations.  The coarse grid problems areformulated using a space-time analog of the full approximationscheme popular in multigrid methods for nonlinear equations.  Thecurrent approach is intended to provide an additional avenue forparallelization for PDE simulations that are already saturated inthe spatial dimensions.  Numerical results and timings on PDEs inone, two, and three space dimensions demonstrate the potential forthe approach to provide efficient parallelization in the temporaldirection.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7uii03t3ucjv1ie1bp3cr30hco","2012-06-12 11:12:19","2012-10-01 11:52:55"
"1186","4","Transfer operator approach for finite time coherent sets identification","2012-10-24 15:00:00",NULL,"SAS 4201","Naratip Santitissadeekorn",NULL,"UNC Chapel Hill",NULL,NULL,"For many application areas, it is becoming important to under transport mechanisms underlying time-dependent dynamical systems. In particular, it is interesting to identify coherent sets, which are minimally dispersive as moving with the flow and typically present important physical structures such as long-lived vortices in oceans or atmosphere. This presentation will concentrate on a transfer operator approach for a finite-time coherent set identification. Few illustrative examples of its application in a geophysical model and atmospheric flow will be presented.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/91d03vhdq6buba71c4c3e0g68o","2012-07-07 13:31:15","2012-10-05 11:19:54"
"1187","4","Mathematical modeling of the mucus barrier in human lungs","2012-10-10 15:00:00",NULL,"SAS 4201","Paula Andrea Vasquez","http://www.unc.edu/~pvasquez/","UNC Chapel Hill",NULL,NULL,"The first line of defense of human lungs against inhaled pathogens is mucus.  Inhaled viruses, bacteria and particulates land on the mucus layer and diffuse within.  These foreign particles are cleared if flow of the mucus layer toward the larynx dominates particle diffusion through the layer.  Yet the flow and diffusive transport properties of mucus remain very poorly understood.  In this lecture I will survey the mathematical challenges in characterizing mucus transport properties.  The talk will focus on progress of our research group understanding remarkable nonlinear phenomena in the oscillatory flow of viscoelastic fluids, and explaining why dynamic and spatial microstructural characterization is essential in the understanding of mucus transport. These research projects involve collaborations at UNC that are either inspired by or directly related to experiments carried out in the Physics Department and Cystic Fibrosis Center.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1cbttesb8ushjm769h8fhqafs4","2012-07-20 14:02:09","2012-10-03 14:51:55"
"1188","4","Using Conservation Laws in Nonlinear Wave Equations","2012-09-12 15:00:00",NULL,"SAS 4201","Christopher Waide Curtis","http://amath.colorado.edu/faculty/curtis/","University of Colorado at Boulder","Mark Hoefer",,"Nonlinear wave equations are ubiquitous throughout the physical sciences.  While appearing in very different contexts, ranging from fluids to quantum mechanics, many equations share a common mathematical structure via conservation laws.  In this talk, we present results showing how conservation laws are used to analyze two different systems.  The first case we study is how perturbations of web-solutions of the Kadomtsev-Petviashvilli equation evolve.  Here we use conservation laws to develop an asymptotic method that allows us to show perturbations of web-solutions remain well-behaved on asymptotically significant time scales.  We also study the impact of dissipation on web-solutions and show that ``shelves"" form as in the case of the Korteweg--de Vries equation.     

In the second part of the talk, we study a nonlocal Gross-Pitaevskii equation which models a periodically trapped Bose-Einstein condensate with nonlocal interactions between particles.  First, using the Hamiltonian structure of the model equation, we show that the nonlocal model has a local model as a limit on any time scale.  This shows that the nonlocal model introduces perturbations to solutions of the local model in a continuous way.  Then, using Krein signature arguments, we establish the stability of a family of solutions to the nonlocal equation.  ","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cdhrnhlhmmo6h2oo4gujfm9aso","2012-07-20 17:31:31","2012-08-24 12:52:18"
"1189","3","Kronecker coefficients for one hook shape","2012-09-24 15:00:00",NULL,"SAS 4201","Jonah Blasiak",,"University of Michigan",,,"The Kronecker coefficient $g_{\lambda \mu \nu}$ is the multiplicity of an irreducible $\mathcal{S}_n$-module $M_\nu$ in the tensor product $M_\lambda \otimes M_\mu$.  A fundamental open problem in algebraic combinatorics is to find a positive combinatorial formula for these coefficients.
We give such a formula in the case  that one of the partitions is a hook shape. Our main tool is Haiman's \emph{mixed insertion}, which is a generalization of Schensted insertion to colored words.","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/onjg8pd9p72jlelpqf52pl96gk","2012-07-22 22:18:22","2012-08-28 15:45:23"
"1190","31","The Ornstein-Uhlenbeck process","2012-08-15 13:30:00",NULL,"SAS 3281","John Harlim",,"NC State",,,,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6i9ot7kinackj3tqq2uiqjk4no","2012-08-01 09:49:27","2012-08-03 08:47:56"
"1191","31","Solitary waves","2012-08-22 11:15:00",NULL,"SAS 4201","Mark Hoefer",,"NC State",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bc4bhsc8i0blbh4o06p6lndmlc","2012-08-01 09:53:06","2012-08-18 10:37:36"
"1192","31","Shape derivatives","2012-08-29 11:15:00",NULL,"SAS 4201","Lorena Bociu",,,,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/d185d6etthhd1n1esdfjp0cgas","2012-08-01 09:53:45","2012-08-18 10:39:07"
"1193","31"," Conservation Laws and Nonlinear Wave Equations","2012-09-12 11:15:00",NULL,"SAS 4201","Christopher Waide Curtis","http://amath.colorado.edu/faculty/curtis/","University of Colorado at Boulder",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/25ge89lt3skkk9pptrufjo5hcc","2012-08-01 09:54:40","2012-08-29 13:32:34"
"1194","31","Multiscale description of viscoelastic fluids","2012-10-10 11:15:00",NULL,"SAS 4201","Paula Andrea Vasquez","http://www.unc.edu/~pvasquez/","UNC Chapel Hill",NULL,NULL,NULL,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ipjlafnfgdu2g02p8v1g0pc1so","2012-08-01 09:55:37","2012-10-03 14:51:40"
"1195","31","Spectral Deferred Correction methods for ODEs","2012-10-17 11:15:00",NULL,"SAS 4201","Matthew Emmett","http://www.unc.edu/~mwemmett/","UNC Chapel Hill",NULL,NULL,NULL,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/q8p2s8ebe5qg38a3260pabusn0","2012-08-01 09:56:54","2012-10-01 11:52:20"
"1196","31","Studying probabilistic properties of deterministic systems using the Frobernius Perron operator","2012-10-24 11:15:00",NULL,"SAS 4201","Naratip Santitissadeekorn",NULL,"UNC Chapel Hill",NULL,NULL,NULL,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1cbi92d8kmvjisrj9dvphb42m4","2012-08-01 09:57:40","2012-10-12 11:38:56"
"1197","31","Dispersive Shock Waves","2012-10-31 11:15:00",NULL,"SAS 4201","Nicholas Lowman",,"NC State",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/72vfgmk90lhvgeql9jcj8s7pik","2012-08-01 09:58:20","2012-08-23 21:45:27"
"1198","31","Twophase fluids: Numerical Methods for Tracking Interfaces ","2012-11-07 11:15:00",NULL,"SAS 4201","Shilpa M Khatri","http://www.unc.edu/~khatri/","UNC Chapel Hill",NULL,NULL,NULL,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8s5fh3675q273dvl3lg7gf872g","2012-08-01 09:58:59","2012-10-28 17:50:25"
"1199","31","The Water Wave Problem: Fundamentals, Analytic Formulations, and Issues of WellPosedness in 2D and 3D","2012-11-14 11:15:00",NULL,"SAS 4201","Nathan Totz","http://fds.duke.edu/db/aas/math/ntotz","Duke",NULL,NULL,NULL,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/tf3e4ldi9qds30u9v9d24vjf70","2012-08-01 09:59:38","2012-11-06 11:42:33"
"1200","31","The role of networks in biological systems","2012-11-28 11:15:00",NULL,"SAS 4201","Elana Fertig","http://astor.som.jhmi.edu/~ejfertig/ejfertig/Home.html","Department of Oncology Biostatistics and Bioinformatics Division Sidney Kimmel Cancer Center, John Hopkins University",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/k17llbomo7udo9rj3cp2l41s98","2012-08-01 10:47:05","2012-08-18 10:44:06"
"1201","4","Analysis of the dynamics of networks of coupled switches and oscillators","2012-11-28 15:00:00",NULL,"SAS 4201","Elana Fertig","http://astor.som.jhmi.edu/~ejfertig/ejfertig/Home.html","John Hopkins University",NULL,NULL,"Interpretation of the dynamics of complex networks has been broadly simplified by dynamic analysis of their sub-networks.  In this approach, dominant processes are inferred statistically overrepresented sub-networks, called network motifs.  Nonetheless, the interaction between these motifs critically drive the dynamics of the entire system.  Complex network dynamics have been analyzed with models of systems of coupled switches or systems of coupled oscillators.  However, these network motifs have diverse dynamics, including notably motifs with oscillatory and motifs with switch-like dynamics.  We, therefore, introduce a new modeling framework that describes the dynamics of networks composed of both oscillators and switches. Both oscillator synchronization and switch stability are preserved in these heterogeneous, coupled networks. Furthermore, this model recapitulates the qualitative dynamics for the yeast cell cycle consistent with the hypothesized dynamics resulting from decomposition of the regulatory network into dynamic motifs. Introducing feedback into the cell-cycle network induces qualitative dynamics analogous to limitless replicative potential that is a hallmark of cancer. As a result, the proposed model of switch and oscillator coupling provides the ability to incorporate mechanisms that underlie the synchronized stimulus response ubiquitous in biochemical systems.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ios73fij80romfai08ocrpo6qc","2012-08-01 10:48:06","2012-11-11 20:44:37"
"1202","1","Should you believe it? A mathematical perspective on the science of news","2012-09-21 16:00:00",NULL,"SAS 2203","Rebecca Goldin","http://math.gmu.edu/~rgoldin","George Mason University","Patricia Hersh","http://www.math.ncsu.edu/events/goldin_coll.pdf","News accounts are filled with numbers and implicit advice. How much coffee is too much? Is the internet making us smarter or dumber? Do vitamins improve our health or harm us? In contexts as diverse as criminal courts, opinion surveys, and our personal health, statistics are playing a larger and larger role. Despite our need for clear rendering of numerical information, many media accounts using statistics are misleading. Eye-catching headlines typically promote exaggerated benefits of medical treatment, exaggerated risks of everyday living, and tragic or comic opinions of survey respondents. We will use recent news accounts, both humorous and serious, to illustrate this process and to suggest how to become savvy news consumers.  Numbers can be powerful when we move past politics and morality to clarify what science actually tells us, what it does not, and what it cannot.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/mogicbb869r84s8c19ndq3c6vo","2012-08-10 10:07:07","2012-09-10 08:47:14"
"1203","1","Uncertainty quantification and parameter inference in ocean general circulation models","2012-10-29 16:00:00","2012-10-29 17:00:00","SAS 4201","Omar Knio","http://www.mems.duke.edu/faculty/omar-m-knio","Department of Mechanical Engineering and Materials Science Duke University","John Harlim",NULL,"We discuss the implementation of sparse, adaptive, pseudospectral sampling algorithms to the problem of quantifying uncertainty in ocean general circulation models, generating functional representations of selected quantities of interest to uncertain model inputs, and exploiting these representations for the purpose of model calibration.  We illustrate these applications through large-scale simulations of the oceanic circulation in the Pacific.  Attention is focused on uncertainty in ocean-atmosphere coupling, namely on the parametrization of the wind drag coefficient.  To this end, we introduce a three-parameter characterization of the wind-speed dependence of the drag coefficient and then outline the implementation of a Bayesian inference formalism to update these parameters based on AXBT temperature data obtained during typhoon Fanapi.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/o88ke5t88cjjmgghd9uvlns8o4","2012-08-11 10:29:32","2012-10-09 10:46:29"
"1204","6","A homotopy method based on WENO scheme for solving steady state problems","2012-11-06 15:00:00",NULL,"SAS 4201","Jonathan Hauenstein","www4.ncsu.edu/~jdhauens","NC State","NA Seminar",,"Homotopy methods rely upon deformations from a system of equations that it easy to solve to the system of interest.  In this talk, I will discuss using a homotopy approach based on a weighted essentially non-oscillatory (WENO) scheme with Lax-Friedrichs flux splitting for solving hyperbolic PDEs.  Extensive numerical examples will be presented to demonstrate the efficiency and robustness of this new approach.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/02ism6b3v81uju68rvlebcqvo8","2012-08-13 09:48:36","2012-09-18 14:13:54"
"1205","1","Randomized algorithms for matrix computations","2012-11-08 16:00:00",NULL,"SAS 4201","Ilse Ipsen","http://www4.ncsu.edu/~ipsen","NC State Distinguished Faculty Colloquium",NULL,NULL,"The emergence of massive data sets over the past fifteen years has led to the development of a new class of matrix algorithms, so-called randomized algorithms. Such randomized algorithms are being designed for matrix multiplication, solution of least squares problems, and low-rank approximations. They have been used effectively in applications such as machine learning, population genomics, astronomy, and nuclear engineering.We give a flavor of randomized algorithm for the solution of least squares / regression problems. Along the way we illustrate important concepts from numerical analysis (conditioning and pre-conditioning) and statistics (sampling and leverage scores).","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/h6u4gu3rm2vledccq70pg9erb8","2012-08-13 11:19:25","2012-11-02 16:32:02"
"1206","31","Darboux theory of integrability with some applications","2012-09-19 11:15:00",NULL,"SAS 4201","Adam Mahdi","http://www4.ncsu.edu/~amahdi","NC State",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hvi4og0kdghiquj26els27rrj4","2012-08-14 21:03:18","2012-09-09 21:35:41"
"1207","31","Basic Concepts of Sensitivity Analysis","2012-10-29 11:15:00",NULL,"SAS 1216","Omar Knio","http://www.mems.duke.edu/faculty/omar-m-knio","Duke",NULL,NULL,NULL,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kaiiuk7b8k3vinu6qp9ktqs51k","2012-08-14 21:05:50","2012-10-18 09:37:14"
"1208","1","Differential algebraic equations and optimal control","2012-11-29 16:00:00",NULL,"SAS 4201","Steve Campbell","http://www4.ncsu.edu/~slc","NC State Distinguished Faculty Colloquium",NULL,NULL,"After a brief introduction to differential algebraic equations we will discuss some of the issues in the numerical solution of optimal control problems involving differential algebraic equations.  Time permits only discussing some aspects of these problems. Technical details will be kept to a minimum so that the talk will hopefully be accessible to a wider audience.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/k3iocr5df7alb4qkj9i7ak7o2o","2012-08-16 10:24:52","2012-11-02 17:05:00"
"1209","14","NCSU Math Department Fall 2012 Meeting","2012-08-20 14:30:00",NULL,"SAS 1102",,,,,,"All NCSU Math Department Graduate Students, Faculty, Staff, Post Docs, Emeritus, etc. are invited to attend the Fall 2012 Meeting.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i6dih3g5tvn5neavtrisur40gg","2012-08-17 15:39:47",NULL
"1210","14","NCSU Math Department Refreshments","2012-08-20 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/tr49943u7kt0eqg17smlodgka0","2012-08-17 15:41:03",NULL
"1211","31","Inverse Problems","2012-09-05 11:15:00",NULL,"SAS 4201","Kristen Brown",,"NC State",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/q4irt54svtn09nureesn1j6ct4","2012-08-18 10:45:18",NULL
"1212","14","Departmental Tea and Cookies","2012-08-22 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nn1s3acni1iu714l876qdrb5sg","2012-08-22 12:06:09",NULL
"1213","24","MGSA Pizza Party","2012-08-22 17:00:00",NULL,"SAS 4104",,,,,,"Greetings from MGSA,

We would like to welcome you all back to school with a pizza party this week.  It will be held this week on Wednesday at 5PM in the 4th floor math commons in SAS.  In addition to serving great food, we will be selling math department mugs ($5) and water bottles ($2).  

We hope to see you all there!

Kristy Brown                   President
Rachael Gordon-Wright    Vice President
Mami Wentworth             Treasurer
Elisabeth Brown              Secretary","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/t6060dfu6sur2jk6am9u90amvo","2012-08-22 16:01:39",NULL
"1214","26","AMGSS Meeting","2012-08-27 16:00:00",NULL,"SAS 4201",,,,,,"We will be having our first meeting next Monday at 4pm in SAS 4201 to plan out presentation times. So please come with a few dates in mind if you plan to present this semester! ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b4g2cmbkt3m3dselbup6gjbctg","2012-08-22 16:03:27",NULL
"1215","3","Factoring Macdonald polynomials at roots of unity","2012-09-10 15:00:00",NULL,"SAS 4201","Elizabeth Niese",,"Marshall University, WV",,,"In recent years there has been great interest in the combinatorics of Macdonald polynomials. Descouens and Morita used symmetric function identities to prove a factorization formula for the modified Macdonald polynomial when one parameter is set to a root of unity. They pose the problem of finding a bijective proof of this factorization using Haglund's combinatorial formula, which defines the modified Macdonald polynomials as the generating function of tableaux. In this talk I present a bijective proof of the factorization as well as a discussion of the univariate symmetry of the polynomials. (Joint work with Nick Loehr)","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jmrg9a9uai35s0aro4dip414vs","2012-08-22 19:09:02",NULL
"1216","3","The Lecture Hall Theorem via abacus diagrams","2012-11-05 15:00:00",NULL,"SAS 4201","Edwin O'Shea","http://educ.jmu.edu/~osheaem/","James Madison University",NULL,NULL,"The Lecture Hall Theorem, first stated and proved in 1997 by Bousquet-Melou & Eriksson, generalizes Eulers celebrated result on the bijection between partitions with odd parts and partitions with distinct parts. In this talk we shall present an elementary and reasonably short proof of the Lecture Hall Theorem via abacus diagrams.This is joint work with Laura Bradford, Meredith Harris, Brant Jones, Alex Komarinski and Carly Matson.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/73vt3qe1cg5d9gc7ue2lmtfujg","2012-08-22 19:11:41","2012-10-27 12:13:03"
"1217","4","Numerical Simulation of Short Waves as Nonlinear Solitary Waves","2012-09-26 15:00:00",NULL,"SAS 4201","John Steinhoff","http://www.utsi.edu/faculty/jsteinhoff/steinhoff.htm","University of Tennessee Space Institute","S. Tsynkov",,"A new numerical method has been developed to propagate short wave equation pulses over indefinite distances and through regions of varying index of refraction, including multiple reflections. The method, “Wave Confinement”, can also be used to solve for harmonic waves in the high frequency (Eikonal) limit, including multiple arrivals. The method involves discretizing the wave equation on a uniform Eulerian grid and adding a simple nonlinear “Confinement” term. This term does not change the integrated amplitude (through each point on the pulse surface) or the propagation velocity, or arrival time, and yet results in capturing the waves as thin
surfaces that propagate as nonlinear solitary waves and remain 2-3 grid cells in thickness with no numerical spreading. With the method, only a simple discretized equation is solved each time step at each grid node. In this way, the complex logic of current methods, such as “Ray Tracing”, which involve allocation of markers to each surface and interpolation as the markers separate, is avoided. With the new method, even though the surfaces can pass through each other and involve a nonlinear term, there is no interaction effect from this term on the variables of interest, allowing the linear wave equation to be accurately simulated. This is due to the form of the difference operators of the added term. The new method should be important in many areas of wave propagation, from radar scattering and long distance communications to cell phone transmission.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1gikjs4fhauaj8rojiobufu7jg","2012-08-23 15:11:29","2012-09-05 21:21:48"
"1218","31","Solving Wave Equations Using Nonlinear Solitary Waves","2012-09-26 11:15:00",NULL,"SAS 4201","John Steinhoff","http://www.utsi.edu/faculty/jsteinhoff/steinhoff.htm","University of Tennessee Space Institute",,,"A simple method is described to construct nonlinear solitary waves (NSW’s) that propagate as wave fronts of solutions to the linear wave equation, and other hyperbolic equations. These NSW’s can serve as basis functions to transport conserved variables, which can be used to reconstruct the wave. This approach is similar to that of Whitham. The modifications required to generate these NSW’s involve adding two simple terms: a negative dissipation and positive dissipation. These must have a nonlinear component and must be homogenous of degree one. When discretized, the solutions persist indefinitely and are true asymptotic solutions, unlike conventional discrete “intermediate asymptotic” solutions which eventually decay.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qf1aa5pnq5ak04d6qiic6b37kg","2012-08-23 21:43:37","2012-09-11 06:28:58"
"1219","22","Hey! That's not my hat! Derangements and the number e","2012-08-29 16:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2012/082912.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oupnm1kgg02r3bce4470e43rko","2012-08-27 10:04:02",NULL
"1220","22","Why should I study math?  What can I do with a math degree?","2012-09-05 16:00:00",NULL,"SAS 2102","Lorena Bociu",,"NC State",,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8h68oh9mh0p69t2noljcv7hu04","2012-08-27 10:05:09",NULL
"1221","22","The Magnificent LaTeX: Typesetting that will  amaze your friends and impress your teachers","2012-10-17 16:00:00",NULL,"SAS 2102","Shirley Law",NULL,"NC State",NULL,"http://www4.ncsu.edu/~nreadin/sum/fall2012/101712.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/04aikllleb5g15mu46ohk0nopg","2012-08-27 10:06:04","2012-10-10 08:07:14"
"1222","22","When polyhedron met polynomial","2012-10-24 16:00:00",NULL,"SAS 2102","Seth Sullivant",NULL,"NC State",NULL,"http://www4.ncsu.edu/~nreadin/sum/fall2012/102412.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hjbgffpf6nqs08jubrccscevd0","2012-08-27 10:06:33","2012-10-17 11:23:08"
"1223","14","Departmental Tea and Cookies","2012-08-27 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/67c61vgofqfoclimg79nu15kg8","2012-08-27 10:52:10",NULL
"1224","21","2012 Todd Fuller Contest","2012-10-13 09:00:00",NULL,"SAS 2203",NULL,NULL,NULL,NULL,"https://www.math.ncsu.edu/undergrad/ncsu_contests/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qmaakk39bg5393iaqoo4o5osm8","2012-08-28 00:19:07","2012-10-18 08:40:19"
"1225","14","Departmental Tea and Cookies","2012-08-29 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/piptt7eca3en7p3uvvg83u0o0g","2012-08-29 20:30:30",NULL
"1226","28","Speed Friending","2012-09-07 15:00:00",NULL,"SAS 2102","Various Women in Mathematics",,,"AWM",,,"mmtolley","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ma623a02uj0dl9s65dgsf1umjk","2012-08-30 09:17:53",NULL
"1227","8","The differential algebra approach to identifiability of nonlinear ODE models","2012-10-02 16:30:00",NULL,"SAS 4201","Nicolette Meshkat","http://www.math.ucla.edu/~nmeshkat/","NC State","Seth Sullivant",,"Parameter identifiability analysis for dynamic system ODE models concerns finding which unknown parameters can be quantified from given input-output data.  If all the parameters of a model have a finite number of solutions, then the model is said to be identifiable.  However, many models are unidentifiable, i.e. the parameters can take on an infinite number of values and yet yield identical input-output data.  This problem has been especially apparent in Systems Biology.  In this talk, we examine unidentifiable models and a differential algebra method for finding globally identifiable parameter combinations using Groebner Bases.  We demonstrate our algorithm on some simple biological models and also discuss some possible improvements to the method.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l00li5b2ris7u5s1g5nkotd32o","2012-08-30 15:33:48","2012-09-14 09:05:08"
"1228","8","On the summability of rational functions","2012-10-30 16:30:00",NULL,"SAS 4201","Shaoshi Chen","http://www4.ncsu.edu/~schen21/","NC State","Michael Singer",NULL,"We present criteria for deciding whether a bivariate rational function can be written as a sum of two (q)-difference bivariate rational functions.  Using these criteria, we show how certain double sums can be evaluated, first, in terms of single sums and, finally, in terms of values of special functions.  This is a joint work with Michael F. Singer.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9hf08ka1ite08j51800cnp8mnc","2012-08-31 09:54:38","2012-10-12 14:31:11"
"1229","14","Departmental Tea and Cookies","2012-09-05 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/13fo8bd4k9l3k6qp34adl11r0k","2012-09-05 00:11:25",NULL
"1230","3","Twisted Frobenius  Schur indicators for Hopf algebras","2012-10-08 15:00:00","2012-10-08 16:00:00","SAS 4201","Maria Vega",NULL,"NC State",NULL,NULL,"The classical Frobenius-Schur indicators for finite groups are character sums defined for any representation and any integer $mge 2$. In the familiar case $m2$, the Frobenius-Schur indicator partitions the irreducible representations over the complex numbers into real, complex, and quaternionic representations.  In recent years, several generalizations of these invariants have been introduced.  Bump and Ginzburg, building on earlier work of Mackey, have defined versions of these indicators which are twisted by an automorphism of the group. In another direction, Linchenko and Montgomery have defined Frobenius-Schur indicators for semisimple Hopf algebras.  We construct twisted Frobenius-Schur indicators for semisimple Hopf algebras these include all of the above indicators as special cases and have similar properties.  This is joint work with Daniel Sage.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kc2ohsr9tiiiu9urvlr4sipqk0","2012-09-05 12:34:03","2012-09-26 18:13:58"
"1231","19","Graduate Algebra Seminar Organizational Meeting","2012-09-10 16:00:00",NULL,"SAS 2102","Graduate Algebra Seminar",,"North Carolina State",,,"We will be discussing potential topics/papers for the journal club, and getting a feel where the research interests of the attendees lie, and also getting a feel for when students will be wanting to speak this semester.  For example, we would like to know who will be wanting to speak towards the end in order to prepare for the joint meetings.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ecbosr7h4jesmiukbbacq7ukdc","2012-09-06 11:02:13",NULL
"1232","8","Calculus on Riemann Surfaces in Python","2013-03-19 16:30:00",NULL,"SAS 4201","Chris Swierczewski","http://www.cswiercz.info/","Washington","Jon Hauenstein",NULL,"Computational tools in algebraic geometry are key to generating new conjectures and providing a means for computing with Abelian functions and solving problems in applications such as integrable systems, convex optimization, and number theory. Recent features in Python for performing computations with Riemann surfaces via complex plane algebraic curves and Riemann theta functions provide steps towards computational solutions to these problems. In this talk we will discuss current and future developments in computing on Riemann surfaces using the Python package &quot;abelfunctions&quot;.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uimrjqao4sq59em1f1j3n7h7lk","2012-09-07 08:45:50","2013-03-17 12:44:50"
"1233","4","Simulating Large-Scale Brain Networks","2012-10-03 15:00:00",NULL,"SAS 4201","Flavio Frohlich","https://www.med.unc.edu/psych/directories/faculty/flavio-frohlich-phd","UNC Chapel Hill","Mette Olufsen",,"Macroscopic activity states in brain networks mediate cognition and behavior. Pathological changes in these network dynamics are associated with both neurological and psychiatric disorders. Studying how cellular elements give rise to activity dynamics represents a promising approach to understanding and eventually treating disorders of the central nervous system. Here, we introduce large-scale simulations of neuronal networks to study (1) how network topology gives rise to network dynamics and (2) how brain stimulation can be used to modulate and enhance macroscopic network dynamics. We demonstrate that global weak perturbations of neuronal signaling is a powerful brain stimulation approach and show experimental results from animal electrophysiology and a human trial that demonstrate the feasibility of this novel brain stimulation paradigm based on transcranial current stimulation. (Joint Seminar with Biomath)","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mcmgli6kbeducegkqk4qftj68o","2012-09-08 18:31:21","2012-09-17 19:00:45"
"1234","6","Hybrid Monte CarloDeterministic Methods for the Simulation of Neutron Transport Problems","2012-10-02 15:00:00",NULL,"SAS 4201","Ed Larsen","http://www-ners.engin.umich.edu/people/larsen.html","Department of Nuclear Engineering  Michigan","NA Seminar NE Department",NULL,"Since the early 1950s, two distinct algorithm classes have been developed for simulating neutral particle transport problems: deterministic (discrete ordinates) methods, and stochastic (Monte Carlo) methods. Nearly all large-scale neutron/photon transport codes are based on one of these two approaches.     Since the mid 1990s, hybrid methods  which combine features of the Monte Carlo and Deterministic methodologies  have been developed and shown to be advantageous. This talk will review (i) deficiencies in standard Monte Carlo and deterministic methods that motivate hybrid transport methods, (ii) the concepts that underlie some of the new hybrid methods, (iii) their advantages and disadvantages, (iv) their performance, and (v) the current status of their implementation in production codes. Professor Larsen will also be speaking to the NCSU SIAM Student Chapter about his somewhat non-standard career path.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rlv8qc0eoovsapnr8qc2jr4no8","2012-09-09 14:46:49","2012-09-20 19:15:43"
"1235","14","Departmental Tea and Cookies","2012-09-12 14:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p4u6mpstnub4fqo0evb151sbss","2012-09-10 08:49:30",NULL
"1236","14","MGSA T-Shirt Design Voting / Departmental Tea and Cookies","2012-09-19 14:30:00","2012-09-19 15:00:00","SAS 4104",,,,,,"The Math Graduate Student Association (MGSA) is co-hosting the department tea September 19th. We will be providing cake and we'll be having voting for our Math Department T-Shirt Design Contest. ","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3gm2vt03tgdbcr2spmqifsbg7o","2012-09-10 08:49:55","2012-09-17 15:05:33"
"1237","14","Departmental Tea and Cookies","2012-09-26 14:30:00","2012-09-26 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i4h6n3u82o0qr2nm9jbt7pt9i0","2012-09-10 08:50:14","2012-09-24 13:03:40"
"1238","14","Departmental Tea and Cookies","2012-09-21 15:30:00",NULL,"SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ru8ugdpvf3j4ci55f0btbqdbbc","2012-09-10 08:50:58",NULL
"1239","23","How to Get a Job at a Liberal Arts College ... and What It's Like to Work There","2012-09-14 15:00:00",NULL,"SAS 4201","Ruth Haas",,"Smith College","Ralph Smith",,"Although we are early in the semester, it is not too early for final year graduate students and postdocs to be thinking about the job application process.  In this week's RTM, visiting professor Ruth Haas will give a seminar focusing on the application timeline and process for liberal arts colleges as well as give a perspective of what it is like to work there.  Please come prepared with questions.
","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f3ao8fa8h55jo27rg4fc760cks","2012-09-10 15:41:33","2012-09-10 17:47:23"
"1240","6","Numerical Methods for Shallow Water and Related Models","2012-10-09 15:00:00",NULL,"SAS 4201","Alina Chertok","http://www4.ncsu.edu/~acherto/","NC State","NA Seminar",NULL,"Shallow water models are widely used as a mathematical framework to study water flows in rivers and coastal areas as well as to investigate a variety of phenomena in atmospheric sciences and oceanography. The basic feature of shallow water flows is that the vertical effect can be neglected compared with the horizontal one with a good approximation. This allows a considerable simplification in the mathematical formulation by replacing the vertical momentum equation by the hydrostatic pressure distribution. As a result, such flows are usually described by the shallow water equations. The simplest, yet commonly used, shallow water model is the Saint-Venant system.Specific numerical difficulties different shallow water models have in common are due to the presence of (possibly singular) geometric source terms and/or nonconservative exchange terms. These may lead to the loss of hyperbolicity, nonlinear resonance, very complicated wave structures and, as a result, to appearance of spurious oscillations and slow convergence of numerical methods. Therefore development of highly accurate and efficient numerical methods for these systems is a very important and challenging task.In this talk, I will present central-upwind schemes for the Saint-Venant system of shallow water equations and related problems. I will show how to construct the well-balanced positivity preserving numerical scheme, which accurately balances the flux and the source terms and at the same time preserves positivity of the water depth -- both properties are absolutely required for practical applications of the method. The scheme, derived in both one- and two-dimensional cases, is applied to a variety of problems.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e0hbiubeqfe6v1qqkskhp65j34","2012-09-10 20:39:22","2012-10-03 15:03:20"
"1243","8","Faster exact matrix multiplication?","2012-09-25 16:30:00",NULL,"SAS 4201","Brice Boyer","http://www4.ncsu.edu/~bbboyer/","NC State","Jon Hauenstein",NULL,"We expose techniques used for searching for new Strassen-like matrix multiplication. We use a by-product of these techniques (approximate matrix multiplication) to try and achieve faster /exact/ matrix multiplication. On the other hand, finding new formulas  la Strassen will certainly not improve the asymptotic matrix multiplication complexity, but we are not after that, we are merely searching for more efficient implementations. We show why and how.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8f6hgevc7ch330mgpvd943g7gk","2012-09-11 16:51:24","2012-09-20 09:15:22"
"1244","19","Journal Club:  Computing Node Polynomials for Plane Curves","2012-09-17 16:00:00",NULL,"SAS 2102","Graduate Algebra Seminar","http://www4.ncsu.edu/~redavids/GraduateAlgebra.html","North Carolina State University",,"http://arxiv.org/abs/1006.0218","(Abstract of the paper we are reading by Florian Block) According to the G\""ottsche conjecture (now a theorem), the degree N^{d, delta} of the Severi variety of plane curves of degree d with delta nodes is given by a polynomial in d, provided d is large enough. These ""node polynomials"" N_delta(d) were determined by Vainsencher and Kleiman-Piene for delta <= 6 and delta <= 8, respectively. Building on ideas of Fomin and Mikhalkin, we develop an explicit algorithm for computing all node polynomials, and use it to compute N_delta(d) for delta <= 14. Furthermore, we improve the threshold of polynomiality and verify G\""ottsche's conjecture on the optimal threshold up to delta <= 14. We also determine the first 9 coefficients of N_delta(d), for general delta, settling and extending a 1994 conjecture of Di Francesco and Itzykson.

See http://arxiv.org/abs/1006.0218","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fq1n79mbv3sml0l7n4nvn7jec4","2012-09-12 16:09:28","2012-09-12 16:18:36"
"1245","19","Group Schemes","2012-09-24 16:00:00",NULL,"SAS 2102","John Hutchens","http://www4.ncsu.edu/~jdhutche/","North Carolina State University",,"http://www.springerlink.com/content/x2442x265x648701/","TBA","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9kqq0rtc9hims3h0n6rbgdmf1o","2012-09-12 16:17:23","2012-09-12 17:39:58"
"1247","15","SIAM Student Chapter Meeting","2012-09-18 12:00:00",NULL,"SAS 2106",,,,"Will Cousins",,"The SIAM Student Chapter at NCSU will be hosting its first meeting of the year on Tuesday, September 18, at noon in SAS 2106.  Come to this meeting to find out:

1. How to get a free student membership to SIAM, as well as the benefits of being a SIAM member.  These benefits include, among other things, travel money opportunities.

2. Information about our upcoming speakers for the semester.

This meeting is open to anyone.","wcousin","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/h9b9sq3esd1pe003j5i251h3o4","2012-09-13 21:51:07",NULL
"1248","21","Triangle Lectures in Combinatorics","2012-09-22 09:15:00","2012-09-22 17:00:00","SAS 1102",,,,,"http://www.math.ncsu.edu/TLC/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5ie0u9id1v9shrkm90quf442q0","2012-09-16 21:46:12","2012-09-17 15:04:00"
"1249","22","Cayley's Formula","2012-09-12 06:00:00",NULL,"SAS 2102","Nathan Reading",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2012/091212.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n2e1emdirf0mjlsj805716oo04","2012-09-17 10:03:15",NULL
"1250","22","Solitons in Water Waves","2012-09-19 16:00:00",NULL,"SAS 2102","Mark Hoefer",,"NC State",,"http://www4.ncsu.edu/~nreadin/sum/fall2012/091912.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ajug3h2sse9qqi8af4q813h0sg","2012-09-17 10:04:27",NULL
"1251","22","Modeling the Diffusion of Durian Fragrance in a Crowded Classroom","2012-09-26 16:00:00",NULL,"SAS 2102","Ralph Smith",NULL,"NC State",NULL,NULL,NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gv3icv29i40p3cpcdb11cpivr4","2012-09-17 10:05:10","2012-09-24 11:18:17"
"1252","22","Newton's Method","2012-11-07 16:00:00",NULL,"SAS 2102","Tim Kelley",,,,,,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pahdjhiq63hvmrek6dtphqkpus","2012-09-17 10:05:46",NULL
"1253","8","Tensors and complexity theory","2012-10-23 16:30:00",NULL,"SAS 4201","JM Landsberg","http://www.math.tamu.edu/~jml/","Texas A & M","Jon Hauenstein",NULL,"Many problems from complexity theory in theoretical computer science can be phrased in terms of tensors. I will discuss general measures of the complexity of a tensor and focus on the complexity of matrix multiplication. The tools for this study come from algebraic geometry and representation theory.","dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a2udupsoldt0361o5eie8ehhpc","2012-09-17 22:30:55","2012-10-11 10:59:25"
"1254","31","Brains Explained","2012-10-03 11:15:00",NULL,"SAS 4201","Flavio Frohlich","http://www.frohlichlab.org/","UNC Chapel Hill",,,,"jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/c75kvej3ppfoljrilkrbn03qpk","2012-09-18 10:54:51",NULL
"1260","6","Numerical Algebraic Geometry and Differential Equations","2013-04-09 15:00:00","2013-04-09 16:00:00","SAS 4201","Andrew Sommese","http://www.nd.edu/~sommese","Notre Dame","NA Seminar Jon Hauenstein",NULL,"In the last decade, the construction and implementation of algorithms to numerically compute and manipulate algebraic objects has reached a high level of development.  Recently, this area, Numerical Algebraic Geometry, has been successfully used to investigate systems of differential equations.  This talk will describe some of the recent methods and applications of numerical algebraic geometry to systems of nonlinear differential equations.  At the lowest level, there is brute force solution of the systems of polynomials that often arise from discretizing systems of nonlinear differential equations.  Surprisingly, even the standard algorithms are efficient enough that this approach yields useful new solutions.  More refined methods based on bootstrapping up to larger systems from smaller systems (with guidance from domain decomposition and filtering), have led to many new solutions of complicated nonlinear free boundary problems.  Tracking of solutions as a parameter changes and a system bifurcates has proved to be a flexible method to compute new solutions and find out about the connections between different solutions of a system of differential equations.  Endgames turn out to be an efficient method to solve some hyperbolicconservations law problems.  Besides discussion of the new methods, a discussion of some of the applications will be given.  There will be a discussion of the directions this research is going.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d0e4h9j71ivjog0h060o06d2tg","2012-09-19 12:33:59","2013-04-04 11:40:02"
"1262","19","Classifying Posets using Edge Labelings","2012-10-01 16:00:00","2012-10-01 17:00:00","SAS 2102","Ruth Davidson","http://www4.ncsu.edu/~redavids/","North Carolina State University",NULL,NULL,"Every finite poset has an associated simplicial complex known as the order complex. An edge labeling of a Hasse diagram is often used to show that the order complex of a finite poset is shellable, a methodpioneered by Bjorner and Wachs.  Shellability implies other interesting and useful characteristics of the poset and associated order complex.   Many types of posets are known to admit specific classes of edge-labelings that induce shellings of the order complex. We characterize finite semimodular and geometric lattices as finite lattices admitting certain families of edge labelings, taking things in the ""converse direction."" These results fit into a similar paradigm as Peter McNamaras 2003 characterization of supersolvable lattices as those finite lattices admitting lexicographic shellings induced by Sn-EL-labelings. This is joint work with Patricia Hersh.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8uf0lif4pfmmbfo2rggo7krgb0","2012-09-24 17:39:51","2012-09-24 17:40:40"
"1263","19","Journal Club:  Counting Algebraic Curves with Tropical Geometry by Florian Block","2012-10-15 16:00:00","2012-10-15 17:00:00","SAS 2102","Journal Club","http://arxiv.org/abs/1206.1925",NULL,NULL,"J","(Abstract from the paper we are reading) Tropical geometry is a piecewise linear ""shadow"" of algebraic geometry. It allows for the computation of several cohomological invariants of an algebraic variety. In particular, its application to enumerative algebraic geometry led to significant progress. In this survey, we give an introduction to tropical geometry techniques for algebraic curve counting problems. We also survey some recent developments, with a particular emphasis on the computation of the degree of the Severi varieties of the complex projective plane and other toric surfaces as well as Hurwitz numbers and applications to real enumerative geometry. This paper is based on the authors lecture at the Workshop on Tropical Geometry and Integrable Systems in Glasgow, July 2011.  See http://arxiv.org/abs/1206.1925","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3ebdd95hhk23ts5kv47supvrts","2012-09-24 17:43:40",NULL
"1264","19","TBA","2012-10-22 16:00:00","2012-10-22 17:00:00","SAS 2102","Emily Barnard",NULL,"North Carolina State University",NULL,NULL,NULL,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d9uupnrq4n11465tcju46pq78s","2012-09-24 17:45:39",NULL
"1265","19","TBA","2012-11-05 16:00:00","2012-11-05 17:00:00","SAS 2102","Journal Club",NULL,NULL,NULL,NULL,NULL,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/12aqifpfv6kl2343shbps3esu8","2012-09-24 17:46:47",NULL
"1266","23","Teaching Efficiency","2012-09-28 15:00:00","2012-09-28 16:00:00","SAS 4201","Departmental Faculty and Grad Students",NULL,"NC State","Ralph Smith",NULL,"One of the key challenges for math PhD students is balancing teaching duties and responsibilities with making timely progress towards their degree. For early career graduate student TAs, this involves balancing coursework with grading, recitation and/or office hour duties.  In later years, progress on doctoral dissertation research must be balanced with teaching and managing your own course.  We will discuss this topic from the perspective of teaching efficiently while, at the same time, preserving the quality of instruction and the timely progress on dissertation research.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5vu86l5ljnl1m0l83snj3871nc","2012-09-25 15:56:27",NULL
"1267","4","Averaged kinetic PDEs on networks","2013-02-13 15:00:00",NULL,"SAS 4201","Michael Herty","http://www.opt.rwth-aachen.de/herty/","RWTH Aachen University","Alina Chertock",NULL,"We derive a kinetic equation for flows on directedgraphs with applications to production lines.The kinetic model allows for a spatialhomogenization procedure yielding macroscopic transport equations.Meanfield limits as well as moment model approximations will bestudied.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ltig6mvahprvh108e0i8jcgcks","2012-09-27 20:40:02",NULL
"1268","15","Career Talk","2012-10-02 12:00:00","2012-10-02 13:00:00","SAS 2106","Ed Larsen","http://www-ners.engin.umich.edu/people/larsen.html","University of Michigan",NULL,NULL,"Ed Larsen will be speaking at the SIAM Student Chapter meeting about his extremely varied and interesting career.  Dr. Larsen began as a mathematician and is now a well known nuclear engineer.  He has held a number of academic positions and has worked at Los Alamos National Laboratory.  This will be a very informal meeting with plenty of time for Q & A.  All students (undergraduate and graduate) and faculty are welcome to attend.","wcousin","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dp2eou4v0gtu6mnc8ia7190i8k","2012-09-28 18:33:39",NULL
"1269","6","Averaged kinetic PDEs on networks","2013-02-13 15:00:00","2013-02-13 15:00:00","SAS 4201","Michael Herty",NULL,"Aachen","DE Seminar",NULL,"We derive a kinetic equation for flows on directedgraphs with applications to production lines.The kinetic model allows for a spatialhomogenization procedure yielding macroscopic transport equations.Meanfield limits as well as moment model approximations will bestudied.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4o9h9u6uoiblke1sqavpjed69g","2012-09-29 14:09:07",NULL
"1270","6","Leverage scores, the column subset selection problem, and least squares problems","2012-11-13 15:00:00","2012-11-13 16:00:00","SAS 4201","Petros Drineas","http://www.cs.rpi.edu/~drinep/","Rensselaer Polytechnic Institute",NULL,NULL,"In this talk we will discuss the notion of leverage scores: a simple  statistic that reveals columns (or rows) of a matrix that lie well within the subspace spanned by the top principal components. Sampling  with respect to leverage scores has been used to speed up solving  least-squares problems, as well as to approximately solve variants of  the column subset selection problem. Finally, leverage scores are deeply connected to the so-called effective resistances of the edges of undirected, positively weighted graphs effective resistances have been critical in approximately solving systems of linear equations with Laplacian matrices as inputs, in time nearly linear to the number of non-zero entries in the input matrix.","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a66ca9pp4hk1uf3lg3sdi3lu9c","2012-09-29 14:13:55","2012-10-01 15:22:52"
"1271","3","Secant Varieties, Symbolic Powers, Statistical Models","2012-10-29 15:00:00","2012-10-29 16:00:00","SAS 4201","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",NULL,NULL,"The join of two algebraic varieties is obtained by taking the closure of the union of all lines spanned by points, one on each variety.  The secant varieties of a variety are obtained by taking the iterated join of a variety with itself.  The symbolic powers of ideals arise by looking at the equations that vanish to high order on varieties.  Statistical models are families of probability distributions with special structures which are used to model relationships between collections of random variables.  This talk will be an elementary introduction to these topics.  I will explain the interrelations between these seemingly unrelated topics in particular, how symbolic powers can shed light on equations for secant varieties, and how theoretical results on secant varieties shed light on properties of mixture models.  Particular emphasis will be placed on combinatorial aspects including connections to graph theory.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mcon369ke470t36eralj6frjfs","2012-10-01 10:44:13","2012-10-16 20:05:44"
"1272","3","Root multiplicities of hyperbolic KacMoody algebras and Fourier coefficients of modular forms","2012-11-12 15:00:00","2012-11-12 16:00:00","SAS 4201","Kyu-Hwan Lee","http://www.math.uconn.edu/~khlee/","University of Connecticut",NULL,NULL,"In this talk, we will consider the rank 3 hyperbolic Kac-Moody algebra, studied by Feingold and Frenkel in 1983, and generalized Kac-Moody algebras that contain the hyperbolic Kac-Moody algebra. The denominator funtions of the generalized Kac-Moody algebras are closely related to certain modular forms. We will compute asymptotic formulas for the Fourier coefficients of the modular forms using the method of Hardy-Ramanujan-Rademacher, and obtain an asymptotic bound for root multiplicities of the rank 3 hyperbolic Kac-Moody algebra. This is a joint work with Henry Kim.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tl90i80247ljeba123ca8cjers","2012-10-01 20:48:08","2012-10-27 12:14:39"
"1273","14","Departmental Tea and Cookies","2012-10-10 14:30:00","2012-10-10 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2nhea5on8va4rjc0k0c7mderog","2012-10-08 08:35:05","2012-10-10 10:50:43"
"1274","8","Exact algorithms for stochastic games and real algebraic geometry","2012-10-16 16:30:00",NULL,"SAS 4201","Elias Tsigaridas","http://www-polsys.lip6.fr/~elias/index.html","INRIA,UPMC","Erich Kaltofen",NULL,"Shapleys discounted stochastic games and Everetts recursive games are classical models of game theory describing two-player zero-sum games of potentially infinite duration.  We present an exact algorithm for solving such games based on separation bounds from real algebraic geometry. When the number of positions of the game is constant, the algorithm runs in polynomial time and is the first with this property.If time permits, we will also present lower bounds on the algebraic degree of the values of stochastic games, induced from the irreducibility of polynomials that have coefficients that depend on the combinatorial parameters of the games, based on a generalization of Eisenstein criterion.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kp398ekaf0bcrsmf3l2ekik348","2012-10-08 09:26:27","2012-10-12 14:31:31"
"1275","23","Curriculum Vitae, Research and Teaching Statements","2012-10-12 15:00:00","2012-10-12 16:00:00","SAS 4201","Departmental Faculty",NULL,"NC State","Ralph Smith",NULL,"For students and postdocs applying for either academic or nonacademic positions, CVs and research statements are often required as part of the application package.  Additionally, teaching statements are typically required when applying for academic positions.  In this weeks RTM, a faculty panel will discuss strategies for writing effective CVs and research and teaching statements.  Examples will be provided during the discussion.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/me0a8v9781gud5tgcr0nlsrook","2012-10-09 18:49:28",NULL
"1276","3","Algebraic cycles and Tate classes on Hilbert modular varieties","2012-11-26 15:00:00","2012-11-26 16:00:00","SAS 4201","Heekyoung Hahn","http://www.math.duke.edu/~hahn/","Duke University",NULL,NULL,"Let E/Q be a totally real number field that is Galois over Q, and let pi be a cuspidal, nondihedral automorphic representation of GL_2(A_E) that is in the lowest weight discrete series at every real place of E. The representation pi cuts out a ""motive"" M_et(pi^infty) from the l-adic middle degree intersection cohomology of an appropriate Hilbert modular variety. If l is sufficiently large in a sense that depends on pi we compute the dimension of the space of Tate classes in M_et(pi^infty). Moreover if the space of Tate classes on this motive over all finite abelian extensions k/E is at most of rank one as a Hecke module, we prove that the space of Tate classes in M_et(pi^infty) is spanned by algebraic cycles. This is joint work with J. Getz.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hl87o06vo71un0bcvdtch3l3do","2012-10-11 21:30:03","2012-11-16 10:47:22"
"1277","14","Departmental Tea and Cookies","2012-10-17 14:30:00","2012-10-17 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6nslu5k1rgj2bb8sdip8sqofbc","2012-10-15 08:41:44",NULL
"1278","8","Root isolation bounds","2012-10-17 16:00:00","2012-10-17 16:20:00","SAS 4201","Aaron Herman",NULL,"NC State","Jon Hauenstein",NULL,NULL,"jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6ej19m2skikgnr8ovelvkfqa5g","2012-10-16 15:56:37","2012-10-16 16:00:01"
"1279","8","Computing a sparse shift under the presence of noise and outlier errors","2012-10-17 16:20:00","2012-10-17 16:50:00","SAS 4201","Matthew Comer",NULL,"NC State","Jon Hauenstein",NULL,NULL,"jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j6ehlk71t8fcuje5clu18j0g1o","2012-10-16 16:01:43",NULL
"1280","8","Isomorphism of polynomials","2012-10-17 16:50:00","2012-10-17 17:20:00","SAS 4201","Ludovic Perret","http://www-polsys.lip6.fr/~perret/","UPMC","Jon Hauenstein",NULL,NULL,"jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8uoa2uns7ogkaqeju47o402kuk","2012-10-16 16:02:51","2012-10-16 16:04:46"
"1281","8","Bound in Viros polynomials for Hilbert 16th problem","2012-10-17 17:20:00","2012-10-17 17:40:00","SAS 4201","Jason Yellick",NULL,"NC State","Jon Hauenstein",NULL,NULL,"jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b0bu1mn9t9m5la264nud7oue08","2012-10-16 16:03:56",NULL
"1283","21","Transport Models for Collective Dynamics in Biological Systems","2013-01-15 08:00:00","2013-01-19 17:00:00","SAS 4201",NULL,NULL,NULL,NULL,"http://www.ki-net.umd.edu/content/conf?event_id=18",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vrn3hma6e95fq9vkdp0chc0b68","2012-10-18 14:51:40",NULL
"1284","14","Departmental Tea and Cookies","2012-10-24 14:30:00","2012-10-24 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/97au6l9vh6o1ribthm95rk6vq4","2012-10-22 09:00:03",NULL
"1285","23","Presentations Using PowerPoint with LaTeXiT","2012-10-26 15:00:00","2012-10-26 16:00:00","SAS 4201","Ralph Smith",NULL,"NC State","Ralph Smith",NULL,"Constructing slides for effective presentations will be critical throughout your career.  Whereas LaTeX-based software such as Beamer can certainly be used for presentations, the incorporation of graphics and movies can be cumbersome, and PowerPoint is required by many employers and funding agencies. In this module, we will show how one can have the best of both worlds by using packages such as LaTeXiT to incorporate mathematics into PowerPoint. This combines the best features of both packages for efficiently constructing mathematics presentations.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b195p3ob9epqmsdt1md28b8r7o","2012-10-22 13:18:09",NULL
"1287","4","Symplectic Semiclassical Mechanics","2012-11-16 15:00:00","2012-11-16 16:00:00","SAS 4201","Tomoki Ohsawa","http://www-personal.umd.umich.edu/~ohsawa/",NULL,"D Zenkov",NULL,"I will talk about the geometry and dynamics of semiclassical wave packets, which provide a description of the transition regime between quantum and classical mechanics.It is well-known that both classical and quantum mechanical systems are described as Hamiltonian systems: finite-dimensional ones for the former, and infinite-dimensional for the latter there are also corresponding (symplectic) geometric structures associated with both descriptions.I will talk about how to exploit such geometric structures to ""strip away"" quantum effects from quantum systems and incorporate them into the classical description to approach semiclassical mechanics from the symplectic-geometric or Hamiltonian point of view.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9h0kut63ev14anqnijrang24os","2012-10-26 07:52:31","2012-10-26 10:38:15"
"1288","14","Departmental Halloween Tea and Cookies","2012-10-31 14:30:00","2012-10-31 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/f86b9ect0nfl3d9nfjuvn4puq0","2012-10-29 09:25:03",NULL
"1289","14","Departmental Tea and Cookies","2012-10-29 15:30:00","2012-10-29 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/h86ld4bmgel323rs87qsnj4hv8","2012-10-29 14:42:06",NULL
"1290","14","Departmental Tea and Cookies","2012-11-08 15:30:00","2012-11-08 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rl8ess4hvhaughg8ek6hkofji8","2012-11-07 09:16:48",NULL
"1291","23","Final Year Timelines and Strategies","2012-11-09 15:00:00","2012-11-09 16:00:00","SAS 4201","Departmental Faculty",NULL,"NC State","Ralph Smith",NULL,"The final year of a Masters, PhD or Postdoctoral program involves a number of deadlines and requirements that are often bewildering. For example, when should one set up their committee, schedule their preliminary exam, apply for jobs, and schedule their defense?  Moreover, how should one budget time for job interviews while finishing their research?  In this RTM, we will discuss a number of these issues to help clarify what needs to be completed during the final year of graduate school or a postdoc program.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j7n9m5tl867rkd4kuetete4mv8","2012-11-07 12:06:54",NULL
"1292","3","Roots of the derivative polynomials for tangent and secant and the Tchebyshev transform of a simplicial complex","2013-01-29 15:00:00","2013-01-29 16:00:00","SAS 1102","Gabor Hetyei","http://math.uncc.edu/~ghetyei/","UNC Charlotte",NULL,NULL,"We introduce the Tchebyshev triangulation of a simplicial complex and explain how counting faces in such triangulations is related to the derivative polynomials for tangent and secant. We prove that the roots of these derivative polynomials are all distinct, pure imaginary, of length at most one, and interlaced. The proof uses combinatorics andanalytic results related to the argument principle. As a consequence, the derivative polynomials for hyperbolic tangent and secant have real roots. We will also discuss some generalizations of our statement.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ijbuc71shhbo6smmfo2udb6eu8","2012-11-08 11:29:52","2013-01-24 09:51:10"
"1293","3","Generalized Mordell curves, generalized Fermat curves, and the Hasse principle","2012-11-16 15:00:00","2012-11-16 16:00:00","SAS 2102","Dong Quan Nguyen","http://www.math.ubc.ca/~dongquan/","University of British Columbia",NULL,NULL,"We show that for each prime p congruent to 1 (mod 8), there exists a threefold X_p such that the existence of certain rational points on X_p produces families of generalized Mordell curves and of generalized Fermat curves that are counterexamples to the Hasse principle explained by the Brauer-Manin obstruction. We also introduce a notion of the descending chain condition (DCC) for sequences of curves, and prove that there are sequences of generalized Mordell curves and of generalized Fermat curves satisfying DCC.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ula301q4uo3br6ha53fdjf8uvc","2012-11-08 14:26:01","2012-11-08 14:36:59"
"1294","15","Guest Speaker from Novozymes","2012-11-13 12:00:00","2012-11-13 13:00:00","SAS 2106","Nick Giffen",NULL,NULL,NULL,NULL,"Nick Giffen, a former NCSU grad, will be speaking about his job at Novozymes, a biotech company.  As always, the discussion will be informal with lots of time for questions, and lunch will be provided.  All are welcome.","wcousin","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n438jj37tovl0c8hvqfaqv92mc","2012-11-12 11:19:18",NULL
"1295","14","Departmental Tea and Cookies","2012-11-14 14:30:00","2012-11-14 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i5htqqq5fvstnek6dau31bpnek","2012-11-14 09:54:01",NULL
"1296","22","Two triangles in a torus","2012-11-14 16:00:00","2012-11-14 16:50:00","SAS 2102","Nathan Reading",NULL,"NC State",NULL,"http://www4.ncsu.edu/~nreadin/sum/fall2012/111412.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/abkumn4nl5jhk8v2636c0644mc","2012-11-14 10:01:13",NULL
"1297","22","Undergraduate Research Presentations","2012-11-28 16:00:00","2012-11-28 17:00:00","SAS 2102","NC State Undergrads",NULL,NULL,NULL,NULL,"II.  Wednesay, November 28, 2012, SAS 2102, 4-5 pm. (SUM Club)-------------------------------------------------------------------------------------1. John Nardini and Laura Poag Title: Modeling Label Decay in Flow Cytometry DataAbstract:At this time, this project includes six different biological models to represent fluorescent label decay in a cell.  In the first model, the conversions of CFSE to CF-R1 and CF-R2 were assumed to occur at the same rate, an assumption that was later decided to be inaccurate, based on general knowledge of chemical reactions.  Hence, in the second model, they were treated as separate and independent conversions, yielding much more accurate results in describing the data.  To create a model with fewer parameters, the conversion of CFDA-SE to CFSE was assumed to be immediate in the third model, which yielded very similar results to our second model. For each of these systems except for the first model, both exponential and Michaelis-Menten conversion rates are tested. The fourth and fifth models simplify the whole system down to only two components, consisting either or a CFSE term and a general CF-R term, or two CF-R terms. In the final type of biological model, we assume only a single component of total fluorescence and model it with exponential, logistic, and Gompertz fits.-------------------------------------------------------------------------------------2. William Oakley Title: Determining the Spectrum of the Laplacian on Fractal 3N-GasketsAbstract:The Laplacian is the central object of analysis on fractals.  While most work on the Laplacian has been focused on computing the Laplacians spectrum on speci&#64257c fractals, we instead &#64257nd the spectrum on an entire class of fractals, the 3N-Gaskets. This is the class of &#64257nitely rami&#64257ed fractal 3N-Gons that are the attractors of iterated function systems containing 3N contraction mappings. For example, the 3-Gasket is the Sierpinski triangle. The Laplacian on the fractal, and thus its eigenvalues, must be studied by examining the graph Laplacian on approximating graphs. We &#64257nd a function R(z) relating the Laplacian eigenvalues on consecutive graph approximations. We use R(z) along with the eigenvalues of the Laplacian on graph approximations to derive part of the spectrum on the next level.  The rest of the spectrum is found using an exceptional set, a set of values which we provide for arbitrary N.  By repeating this infinitely many times, the spectrum of the Laplacian on the fractal can be found.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/87oqh827n9bca6nr0oe0mj1dvk","2012-11-14 10:02:44","2012-11-26 09:22:42"
"1298","8","Between Sparse and Dense Arithmetic","2012-12-06 16:30:00","2012-12-06 17:30:00","SAS 4201","Dan Roche","http://www.usna.edu/Users/cs/roche/","US Naval Academy","Erich Kaltofen",NULL,"Important problems in varied areas such as celestial mechanics, computational mathematics, and information assurance all rely on computations with very large integers or polynomials. This leads naturally to the question of how these objects should be represented and stored in a computers memory. The two standard approaches for representation are dense and sparse, with the primary difference being whether zeroes in the integer or polynomial are stored explicitly or implicitly. Dense arithmetic works well for small numbers and has seen numerous practical and theoretical advances the basic algorithms are built-in primitives on nearly every microprocessor on the planet. Sparse arithmetic has been studied for at least 50 years, but in the last few decades especially it has seen an explosion of applications and a few notable efficient implementations. This leaves developers with a difficult choice: whether to use dense or sparse arithmetic in their applications. Some programs have in fact been written to efficiently switch from one representation to the other at some point in the middle of a computation. Our aim is to eliminate this difficult binary choice by developing efficient algorithms that work for sparse objects, dense objects, and all the difficult cases in between these two representational extremes. We will give an overview of recent theoretical progress, practical challenges, and some ongoing efforts on further breakthroughs.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u070p0uff4p8mdc6hn9hphe924","2012-11-14 17:17:06","2012-11-27 15:45:20"
"1299","4","Numerical Methods for DAEs of Multibody System Dynamics","2012-11-30 15:00:00",NULL,"SAS 2102","Jieyu Ding",NULL,"University of Qingdao and University of Illinois at Chicago","D Zenkov",NULL,"The dynamics of the state variables of a multibody system is usually described by differential-algebraic equations (DAEs). Thus, solving DAEs becomes an important step in the optimization procedure for multibody systems. The accuracy and stability of a method for solving DAEs directly influences the accuracy and efficiency of optimization.Recently, the time-stepping methods developed in the structural dynamics, such as Newmark method, HHT-&#945 method, WBZ-&#945 method, &#9521 method, generalized-&#945 method, et al. were adapted to multibody dynamics and developed quickly because of their second order convergence and the effective application in flexible or collision multibody dynamics. This talk focuses on the development of energy- and constraint-preserving generalized-&#945 method and its optimization applications.","jharlim","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eps4036rfa4eh4qrav1qpq5fi4","2012-11-14 21:54:28","2012-11-28 05:41:16"
"1300","19","Short Presentations","2012-11-26 16:00:00","2012-11-26 17:00:00","SAS 2102","Nathaniel Schwartz Emma Norbrothen John Hutchens",NULL,NULL,NULL,NULL,"This meeting will consist of several short presentations by students who plan to present at the JMM in San Diego. Nathaniel Schwartz - 10 min.  ""Involutions of algebraic groups over fields of characteristic 2"", Emma Norbrothen - 10 min. ""Classifying the Double Cosets HkGk/Hk of SL(n,k)"", John Hutchens - 20 min. ""k-involutions of G_2 and F_4""","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mc5uamvah94vcp2g242529bkr4","2012-11-18 13:36:46","2012-11-26 09:19:17"
"1301","9","Withinhost parasite interactions and their effects on host health ","2012-11-27 16:30:00","2012-11-27 17:30:00","Cox 306","Emily Griffiths","http://www.emily-griffiths.postgrad.shef.ac.uk","University of Sheffield, UK",NULL,NULL,"Treating one infection could indirectly affect other parasite populations coinfecting the same host. The types of organisms that can coincide in the same host and their effects on host health are often studied, but the indirect effects of treatment are rarely considered when planning or evaluating treatment programmes. I will describe the results of a systematic review of the kinds of coinfecting parasites, their health impacts and the pattern of ecological interactions among the parasite community of humans. I will then focus on the results of a theoretical model of treatment impacts on untreated, coinfecting parasitic worms. The analyses indicate a dominance of ""bottom-up"" resource control of parasite communities that could help develop general treatment guidelines. However the non-monotonic effects of treatment on coinfecting parasites pose difficulties for ecologists seeking to infer interaction strengths between parasite species.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/44k6q4l3cggpsit5rf13ajcug8","2012-11-26 08:26:12",NULL
"1302","14","Undergraduate Research Presentations","2012-11-28 16:00:00","2012-11-28 17:00:00","SAS 2106","Joseph Arthur Laura Barnobi Andre Waschka ",NULL,NULL,NULL,NULL,"I.  Monday, November 26, 2012, SAS 2106, 4-5 pm.-------------------------------------------------------------------------------------1. Joseph ArthurTitle:  Modeling Hepatitis C Viral Dynamics: Sensitivity, Identifiability, and Parameter EstimationAbstract:The recent influx of biomedical data has assisted the development of models to understand the behavior of many human diseases. The practical immeasurability of most of the model components makes theoretical consideration about parameter estimation particularly relevant. In this talk, we present sensitivity and identifiability analyses as the first step in determining unknown parameters in a mathematical model for hepatitis C viral infection. Also, we show results of parameter estimation using available data from the existing literature.-------------------------------------------------------------------------------------2. Laura BarnobiTitle:  Applications of Algebraic Geometry in RoboticsAbstract:The configurations of a robotic arm can be described by a system of polynomial equations. In this talk, I will describe how to obtain and analyze this system of equations using methods of computational algebraic geometry.-------------------------------------------------------------------------------------3. Andre Waschka Title: A Nonsocomial Epidemic Model with Antibiotic ResistanceAbstract:We introduce an individual based model (IBM) formulated as a system ofstochastically determined events to describe the spread of nosocomial (hospital acquired) and antibiotic-resistant infection in intensive care units. Corresponding deterministic models describe the average behavior of the IBM over a large number of simulations. Hence, by randomly assigning patients infection statuses and health care workers contamination statuses, the model shows the possible scenarios for the disease outbreak in an ICU.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/brqupo04mn2n98b1fpdr2n67ko","2012-11-26 09:20:53","2012-11-26 09:22:23"
"1303","14","Departmental Tea and Cookies","2012-11-29 15:30:00","2012-11-29 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/msf38n00j4c33un5al3u1a83jg","2012-11-26 10:28:53",NULL
"1304","23","Interview Strategies","2012-11-30 15:00:00","2012-11-30 16:00:00","SAS 4201","Departmental Faculty",NULL,"NC State","Ralph Smith",NULL,"What type of presentation should you give and what do you do if you cannot answer a question?  Should you try to negotiate salary or benefits during the initial interview?  Is it appropriate to have your mother call the search committee for any reason? What do you do if your cell phone rings during the interview? What do you do if you are late for the interview and how should you dress?These questions and others will be discussed during this weeks RTM.  This session should be of interest to all students and postdocs presently looking for a job.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2j9bln2rct55l61r53m7n53pgc","2012-11-27 13:46:02",NULL
"1306","14","NCSU Fall 2012 Math Dept. Graduation","2012-12-14 15:00:00","2012-12-14 17:00:00","SAS 2203",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8fm76qkn7j1cpqcjh6iogo42uk","2012-12-05 09:50:38",NULL
"1308","31","Faculty Research Presentations","2013-01-09 11:15:00","2013-01-09 12:15:00","SAS 4201","Alina Chertock Xiao-Biao Lin Jack Silverstein",NULL,"NC State",NULL,NULL,NULL,"lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sh15ateb4dovkrqbvrln2tmga0","2012-12-06 14:10:43",NULL
"1309","31","Arterial stenosis: modeling and the inverse problem","2013-01-16 11:15:00","2013-01-16 12:15:00","Park Shops 201 NOTE ALTERNATIVE LOCATION","Zack Kenz",NULL,"NC State",NULL,NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ei2e1rfs18irstuonf99q7melc","2012-12-06 14:13:17","2013-01-10 15:33:20"
"1310","31","Wellposedness analysis for the steadystate Stokes equation","2013-01-23 11:15:00","2013-01-23 11:15:00","SAS 4201","Kelby Stockstill",NULL,"NC State",NULL,NULL,NULL,"lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e7sveec070dosmm6rbdoo8lj1c","2012-12-06 14:14:36","2013-01-15 14:04:57"
"1311","4","A computational and experimental study of flow induced vibrations of broad leaves","2013-04-10 15:00:00","2013-04-10 16:00:00","SAS 4201","Laura Miller","http://www.unc.edu/lam9/pmwiki2/","UNC","John Harlim",NULL,"Flexible plants, fungi, and sessile animals are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. In strong winds, for example, leaves roll up into cone shapes that reduce flutter and drag when compared to paper cut-outs with similar shape and flexibility. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also exhibit this behavior. What is less understood is how the mechanical properties of a two-dimensional leaf in a three-dimensional flow will passively allow roll up and reduce drag.This presentation will begin by examining how leaves roll up into drag reducing shapes in strong flow. The dynamics of the flow around the leaf of the wild ginger Hexastylis arifolia and the wild violet Viola papilionacea are described using particle image velocimetry. The flows around the leaves are compared with those of simplified 2D numerical simulations of flexible beams attached to both rigid and flexible beams. When the beams are attached to flexible tethers, large forces and oscillations due to strong vortex shedding are produced. Experiments with flexible rectangular sheets that reconfigure into U-shapes also experience large vortex-induced vibrations and peak drag forces.In the actual leaf, a stable recirculation zone is formed within the wake of the reconfigured cone. In physical models that reconfigure into cones, a similar recirculation zone is observed with both rigid and flexible tethers. These results suggest that the three-dimensional cone structure in addition to flexibility is significant to both the reduction of vortex-induced vibrations and the forces experienced by the leaf.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6f98513vkm2o1q4913o683k5h4","2012-12-08 16:01:38","2013-04-05 10:54:26"
"1312","31","Asymptotics","2013-01-30 11:15:00","2013-01-30 12:15:00","SAS 4201","Lake Bookman","http://www4.ncsu.edu/~ldbookma/","NC State",NULL,NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fro722vdg587ul9891o0gunka4","2012-12-08 16:05:30","2013-01-24 10:53:18"
"1313","31","Exploiting HF Ambient Noise to Synchronize Distributed Receivers","2013-03-20 11:15:00","2013-03-20 12:15:00","SAS 4201","David Hong",NULL,"Duke University",NULL,NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/veh9ikhvsj7fil9jpdv7e20ll4","2012-12-08 16:08:22",NULL
"1314","8","Hyperbolic Polynomials, Interlacers, and Sums of Squares","2013-02-26 16:30:00","2013-02-26 17:30:00","SAS 4201","Cynthia Vinzant","http://www-personal.umich.edu/~vinzant/","University of Michigan","Jon Hauenstein",NULL,"Hyperbolic polynomials are real polynomials whose real hypersurfaces are nested ovals, the inner most of which is convex. These polynomials appear in many areas of mathematics, including optimization, combinatorics and differential equations.  Ill give an introduction to this topic and discuss the special connection between hyperbolic polynomials and their interlacing polynomials (whose real ovals interlace those of the original). This will let us relate the inner oval of a hyperbolic hypersurface to the cone of nonnegative polynomials and, sometimes, to sums of squares.  An important example will be the bases generating polynomial of a matroid.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lt7a16n3oaes0a51g2lk7jvua8","2012-12-10 10:07:23","2013-02-23 13:12:57"
"1315","1","Flows in karst geometry:  modeling, analysis and simulation","2013-04-04 16:00:00","2013-04-04 17:00:00","SAS 1102","Xiaoming Wang","http://www.math.fsu.edu/~wxm","Florida State University","John Harlim",NULL,"Karst geometry is a particular type of configuration that consists of both conduit/channel (or vug/chamber) together with porous media. Many important applications involve fluid flows in karst geometry. Well-known examples include contaminant transport in karst aquifer, oil recovery in karst oil reservoir, proton exchange membrane fuel cell technology, cardiovascular modeling, and carbon-dioxide sequestration among others. The mathematical study of flows in karst geometry is a challenge due to the coupling of the flows in the conduits and the surrounding matrix, which are governed by different physical processes the possibly complex geometry of the network of conduits the vastly disparate spatial and temporal scales the strong heterogeneity and enormous associated uncertainty in natural karst aquifers and the multiphase nature of many important applications. In this talk, we will present recent results on the modeling, analysis, and simulation of single-phase flows in karst geometry. New phase-field models for two phase flows in karst geometry will be presented as well.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/4p722js20f1guq25h93gskc6fs","2012-12-10 11:12:22","2013-03-29 12:28:56"
"1316","4","Non-monotone feedback controls for beams and plates","2013-03-20 15:00:00","2013-03-20 16:00:00","SAS 4201","Daniel Toundykov","https://sites.google.com/site/danieltweb/","University of NebraskaLincoln","Lorena Bociu",NULL,"Non-monotone feedback controls for beams and platesI will give a brief historical overview of a shear feedback control mechanism that was originally proposed to suppress vibrations in thin beams (e.g., flexible robot arms). The implementations proved efficient, however the mathematical model upon a basic examination appeared unstable and, in fact, possibly ill-posed.The dilemma persisted till a detailed spectral analysis by Z. H. Luo and B. Z. Guo in 97. confirmed the predicted stability properties in the mathematical model.Subsequently further results a more robust approach based on frequency domain analysis was  proposed Lasiecka and Belinsky in 07. I will discuss these findings and show how they can be extended to boundary feedbacks on thin plates.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bpvkcnffp2jnmfag6hiah4ggko","2012-12-10 11:33:55","2013-03-17 14:14:14"
"1317","31","Faculty Research Presentations","2013-02-20 11:15:00","2013-02-20 12:15:00","SAS 4201","Jonathan Hauenstein Tim Kelley Seth Sullivant",NULL,"NC State",NULL,NULL,NULL,"lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gkoljk6nr4638q9e4ceb86p9os","2012-12-10 12:03:30","2013-01-15 14:06:26"
"1318","1","Canonical forms: a mathematician's view of musical canons","2013-01-25 16:00:00","2013-01-25 17:00:00","SAS 2203","Noam Elkies","http://en.wikipedia.org/wiki/Noam_Elkies","Harvard University","Dean Lee Physics","https://www.math.ncsu.edu/events/Elkies.pdf","To write a musical canon--be it Three Blind Mice or the climax of a Bach fugue--one constructs a melody that can act as its own harmony. Thinking about this task leads us to look at musical structure from points of view usually associated with science and mathematics, not the arts. The lecture will be illustrated with diagrams as well as musical examples from various eras and genres (including at least one improvised on the spot), and will require no technical background in either music or mathematics.","dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/mkirrd8fvtip17nhsq4fogjfc8","2012-12-10 12:04:23","2013-01-24 15:07:55"
"1319","21","Kwangil Koh Lecture on Mathematics in Our Time: Patterns Patterns Everywhere","2013-04-16 16:30:00","2013-04-16 17:30:00","SAS 2203","Martin Golubitsky","http://people.mbi.ohio-state.edu/mgolubitsky/","Distinguished Professor of Mathematics and Physical Sciences, Ohio State University",NULL,"http://www.math.ncsu.edu/events/Golubitsky.php","Regular patterns appear all around us, from vast geological formations to ripples in a vibrating coffee cup, from gaits of animals to the lapping tongues of flames. The mathematical notion of symmetry is a key to understanding how and why these patterns form. This lecture will show some of these fascinating patterns and discuss how mathematical symmetry enters the picture.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rnf5d8vvmuil2k6ii567mvr56k","2012-12-10 15:03:40","2013-03-27 10:19:17"
"1320","4","Universal Wave Patterns","2013-04-24 16:00:00","2013-04-24 17:00:00","SAS 4201","Peter Miller","http://www.math.lsa.umich.edu/~millerpd/","University of Michigan","Mark Hoefer",NULL,"A feature of solutions of a (generally nonlinear) field theory can be called &quot;universal&quot; if it is independent of side conditions like initial data. I will explain this phenomenon in some detail and then illustrate it in the context of the sine-Gordon equation, a fundamental relativistic nonlinear wave equation. In particular I will describe some recent results (joint work with R. Buckingham) concerning a universal wave pattern that appears for all initial data that crosses the separatrix in the phase portrait of the simple pendulum.  The pattern is fantastically complex and beautiful to look at but not hard to describe in terms of elementary solutions of the sine-Gordon equation and the collection of rational solutions of the famous inhomogeneous Painleve-II equation.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pvctcoqkoi25nnqotsnjbrm5h0","2012-12-11 11:59:23","2013-04-22 11:44:16"
"1321","31","HighDimensonal Model Representation","2013-02-27 11:15:00","2013-02-27 12:15:00","SAS 4201","Zhengzheng Hu","http://www4.ncsu.edu/~zhu4/Zhengzheng/Welcome.html","NC State",NULL,NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qaim9mltt1iicut1pj2gmqmus8","2012-12-11 14:27:32","2013-02-25 10:41:04"
"1325","4","Radiative transport theory for light propagation in luminescent media","2013-02-06 15:00:00","2013-02-06 16:00:00","SAS 4201","Boaz Ilan","http://faculty.ucmerced.edu/bilan/","UC Merced","Mark Hoefer",NULL,"Luminescent media are ubiquitous in nature and useful in modern technology.  When light propagates through a random luminescent medium, it can undergomultiple absorption and reemission at different wavelengths and directions. Modeling this dynamics is challenging. Most studies rely on Monte Carlo (statistical) simulations or ad-hoc models to address this problem.We propose a deterministic radiative transport theory for this problem that depends on measurable data. We apply this theory to model light propagation in luminescent solar concentrators (LSCs), which are designed to guide sunlight to a photovoltaic solar cell. The LSC performance is studied in detail by computing the solutions of the radiative transport theory and compared with the results of Monte Carlo simulations. The results suggest that optimized LSCs offer a more affordable route to photovoltaic solar cells.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m9q8jduf9r2bro7dg6c5fq3sjc","2012-12-14 13:20:12","2013-01-30 20:17:23"
"1327","31","Waves","2013-02-06 11:15:00","2013-02-06 12:15:00","SAS 4201","Boaz Ilan","http://faculty.ucmerced.edu/bilan/","UC Merced","Mark Hoefer",NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/soq9f6b1nherl81eg227ctm4t8","2012-12-14 13:22:11",NULL
"1329","8","MULTIPLICITY: Software for computing multiplicity structures at zeros of nonlinear systems","2013-04-09 16:30:00","2013-04-09 17:30:00","SAS 4201","Wenrui Hao","http://www.nd.edu/~whao","Notre Dame","Jon Hauenstein",NULL,"Multiplicity is an important invariant of nonlinear systems. In this talk, I will introduce an algorithm based on an equation-by-equation strategy that significanlty improves the efficiency of the multiplicity algorithm and substantially reduces the storage requirement. The equation-by-equation strategy is actually based on a variable-by-variable closedness subspace approach.  As a result, the algorithm can handle much larger nonlinear systems and higher multiplicities than their predecessors.  I will also introduce a Matlab implementation, MULTIPLICITY, of a numerical algorithm for computing the multiplicity structure of a nonlinear system at an isolated zero.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hkf86vsjvc1mlc3fl7tqs18g9s","2012-12-18 14:27:37","2013-03-04 13:09:52"
"1331","6","Fast Factorizations in Recursion Style for Solving Large Systems of Linear Equations with Certain Structures","2013-03-12 15:00:00","2013-03-12 16:00:00","SAS 4201","Xiaobai Sun",NULL,"Duke","Symbolic Computation Seminar",NULL,"Any efficient algorithm for solving a very large system of linear equations exploits the sparse or compressible structure or both in the matrix. Such structures are relatively straightforward to exploit in iterative methods. Many applications admit only linearly scaling solvers in their computational budgets or processing time. Recent efforts on fast direct methods present incredibly competitive results in accuracy and efficiency for systems with hierarchically separable structures, which include many types of sparse matrices and compressible matrices. Such methods can be used also as preconditioners for iterative methods. But they emerge with the following three issues to tackle with : highly complex algorithm structures, limited concurrency potential on emerging parallel computers and the subsequent onerous task in implementation. I introduce in this talk a fast approach with a simple, unifying and recursive factorization for the same class of matrix structures. I introduce also an effective approach, recently developed with my colleagues at Duke and UNC-CH, to implementing such algorithms with ease and efficiency for and by computational mathematicians and scientists.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/iuournqi18cl9c5rd8cc6h9sdk","2012-12-18 14:45:49","2013-03-05 10:25:13"
"1333","31","What is a soliton?","2013-04-24 11:15:00","2013-04-24 12:15:00","SAS 4201","Peter Miller","http://www.math.lsa.umich.edu/~millerpd/","University of Michigan","Mark Hoefer",NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rabiaii9l0e7rg79vaslbv1dhk","2012-12-23 19:11:26","2013-04-22 10:11:05"
"1335","14","Departmental Tea and Cookies","2013-01-14 15:30:00","2013-01-14 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,"Please plan to attend the Spring Departmental Meeting on Monday, January 14th, 4:00 pm - 5:00 pm in SAS 1102. Refreshments will be served at 3:30 pm in SAS 4104.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8fhqt8jmtqoboli6vt2k5gbucc","2013-01-02 12:11:44",NULL
"1337","14","Spring 2013 Mathematics Departmental Meeting","2013-01-14 16:00:00","2013-01-14 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,NULL,"Please plan to attend the Spring Departmental Meeting on Monday, January 14th, 4:00 pm - 5:00 pm in SAS 1102. Refreshments will be served at 3:30 pm in SAS 4104.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gto8h07duvr3qusdkght9484vg","2013-01-02 12:12:38",NULL
"1339","2","Transport phenomena in flows of granular materials","2013-01-15 16:00:00","2013-01-15 17:00:00","SAS 4201","Ivan Christov","http://www.princeton.edu/~christov/","Postdoc Fellow at Princeton","Campbell",NULL,"Flowing granular materials are an example of a heterogeneous complex system away from equilibrium. As a result, their dynamics are still poorly understood. One canonical example is granular flow in a slowly-rotating container. Under some mild assumptions, the kinematics of the flow can be modeled and scalar mixing studied with the advection-diffusion equation paradigm. The shape of the container can induce chaotic trajectories, while the properties of the individual particles can lead to self-organization (demixing). The balance between these two effects leads to intricate persistent mixing patterns, which we show correspond to eigenmodes of an appropriate operator (Christov, Ottino & Lueptow, Phys. Fluids, 2011). However, granular materials do not perform thermally driven Brownian motion, so diffusion is observed in such systems because agitation (flow) causes inelastic collisions between particles. In a variation of the previous experiment, it has been suggested that axial diffusion of granular matter in a rotating drum might be ""anomalous"" in the sense that the mean squared displacement of particles follows a power law in time with exponent less than unity. Further numerical and experimental studies have been unable to definitively confirm or disprove whether a fractional diffusion equation describes this process. We can show that such a ""paradox"" can be resolved using Barenblatts theory of self-similar intermediate asymptotics (Christov & Stone, Proc. Natl Acad. Sci. USA, 2012). Specifically, we find an analytical expression for the instantaneous scaling exponent of a macroscopic concentration profile, as a function of the initial distribution. Then, by incorporating concentration-dependent diffusivity into the model, we show the existence of a crossover from an anomalous scaling (consistent with experimental observations) to a normal diffusive scaling at very long times.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1d2t4h32bnk6nj1sbpv1eiocok","2013-01-07 14:16:02","2013-01-10 13:51:55"
"1341","2","Reincarnations in persistent homology with applications to shape skeleta","2013-01-16 16:00:00","2013-01-16 17:00:00","SAS 4201","Yuriy Mileyko","http://www.math.uiuc.edu/~ymileyko/index.html","University of Illinois","Lloyd",NULL,"Topological data analysis (TDA), a new approach to handlinghigh-dimensional data gained a lot of attention lately. TDA focuses onqualitative rather than quantitative information supported by the data.A central concept in TDA is persistent homology, a topological invariantcapturing structural changes in continuous objects reflected by discretepoint clouds. In particular, persistent homology allows one to determinethe thresholds where new topological features emerge and where they arelater destroyed, providing a so-called birth-death decomposition.Birth-death decompositions have been extensively used in a variety ofapplications. In this talk we will show that if multiple topologicalchanges occur at some threshold then we can obtain additional topologicalinformation by relating features dying at that threshold with the onesthat are created there.This leads to the concept of a reincarnation, a concept very formal at thediagram chasing level, but having a surprisingly rich geometric content.In particular, we use reincarnations to provide an alternative definitionof the medial axis, curve skeleton, and even higher order skeleta, theconcepts that have many useful applications in engineering, computerscience, and biology.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mjbc83hlgvjhmn9akiqvck50ss","2013-01-07 14:18:33","2013-01-10 13:56:34"
"1343","2"," Efficient Localization of Topological Features","2013-01-17 16:00:00","2013-01-17 17:00:00","SAS 4201","Anil Hirani","http://www.cs.uiuc.edu/~hirani/","University of Illinois","Szanto",NULL,"Characterization of topological features (such as clusters, holes, and tunnels) is important for finding patterns in data. It is also useful in many scientific and engineering applications. In some applications, a characterization with smallest measure or sparsest representation is needed. I will describe a polynomial time solution to this problem that works in arbitrary dimension and for a large class of spaces. Before our work, even the solution for the case of 2-dimensional surfaces required time exponential in number of features. We go from intractability to polynomial time by moving from mod 2 to integer coefficients for homology. We characterize the precise class of simplicial complexes for which the boundary matrix is totally unimodular. This allows for a linear programming relaxation of the problem yielding a polynomial time solution. I will also discuss some implications of this result for other problems in computational topology.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r2lgffsdger7fsejg81qmir4mc","2013-01-07 14:20:07","2013-01-14 12:03:44"
"1345","2","Hamiltonian dynamical systems with infinitely many periodic orbits and Floer homology","2013-01-18 16:00:00","2013-01-18 17:00:00","SAS 4201","Basak Gurel","http://www.math.vanderbilt.edu/~gurelzb/","Vanderbilt","Bakalov",NULL,"A general, but not universal, feature of Hamiltonian dynamical systems is that such systems tend to have numerous periodic orbits. In fact, as the Conley conjecture asserts, for a broad class of closed symplectic manifolds, every Hamiltonian diffeomorphism (the time-one map of a Hamiltonian flow) has infinitely many simple periodic orbits. On the other hand, it is easy to see that the conjecture fails for a general symplectic manifold such as the two-dimensional sphere or the Euclidean space.One variant of the Conley conjecture applicable to such manifolds, inspired by a celebrated theorem due to Franks, asserts that a Hamiltonian diffeomorphism with more than necessary fixed points has infinitely many simple periodic orbits. Here the threshold is usually interpreted as a lower bound arising from some version of the Arnold conjecture for instance, it is n+1 for the n-dimensional complex projective space. For the two-sphere, the assertion is a special case of Franks theorem: every area preserving homeomorphism of the sphere with more than two fixed points has infinitely many periodic points.In this talk we will discuss various aspects of the existence question for periodic orbits of Hamiltonian diffeomorphisms, focusing on recent results obtained by Floer homological methods in the realm of higher dimensional generalizations of Franks theorem.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/up53366eaggrrsdh1a859omte8","2013-01-07 14:21:33","2013-01-09 11:18:17"
"1347","2","Categorification in topology and algebra","2013-01-23 16:00:00","2013-01-23 17:00:00","SAS 4201","Radmila Sazdanovic ","http://www.math.upenn.edu/~radmilas/","University of Pennsylvania","Bakalov",NULL,"We will introduce the notion of categorification and discuss several examples. In particular, we will focus on Khovanov homology and chromatic homology theories categorifying the chromatic polynomial for graphs and relations between them. We develop a diagrammatic categorification of the polynomial ring Z[x], based on a geometrically defined algebra and show how to lift various operations on polynomials to the categorified setting. This construction generalizes to categorification of orthogonal polynomials, including Chebyshev polynomials and the Hermite polynomials.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n2tb4gvql57oocilohmpd65d18","2013-01-07 14:22:42","2013-01-14 23:17:30"
"1349","2","Torus quotients in algebraic analysis","2013-01-24 14:30:00","2013-01-24 15:30:00","SAS 4201","Christine Berkesch","http://www.math.duke.edu/~cberkesc/","PostDoc Duke University","Chertock",NULL,"Algebraic analysis, also called the theory of D-modules, is theapplication of algebraic geometry to the study of systems of linearpartial differential equations. Just as algebraic varieties with groupactions admit quotients, we provide a quotient construction for linearPDEs with torus actions that is with several important properties inalgebraic analysis (the theory of D-modules). As an application, we applytools from toric geometry to obtain new information about hypergeometricsystems of PDEs studied by Gauss, Appell, and Lauricella, among others. Inparticular, we determine when such ""Horn systems"" are regular holonomic.This is joint work with Laura Felicia Matusevich and Uli Walther.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5g51ja5eaadlsdoub6phbgoiao","2013-01-07 14:24:00","2013-01-24 09:45:11"
"1351","2",NULL,"2013-01-25 14:30:00","2013-01-25 15:30:00","SAS 4201","David Anderson","http://www.math.washington.edu/~dandersn/","FSMP PostDoc Fellow in Paris","Chertock",NULL,"Schuberts enumerative calculus, the subject of Hilberts 15th problem, is a technique for solving problems of enumerative geometry for example, how many conics are tangent to five given conics? In its modern formulation, Schubert calculus concerns computations in the cohomology rings of Grassmannians, flag varieties, and related spaces. These spaces carry large group actions, which can be used to both refine and simplify the computations. The cohomology calculations can be modeled by multiplication of polynomials, and a central role is played by these polynomial representatives. Formulas for these polynomials are of both theoretical and computational interest. In this talk, I will survey recent developments in this subject, including some new formulas and applications.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pfcveill8lssv1j1k7psfij3mk","2013-01-07 14:25:46","2013-01-24 09:49:51"
"1353","6","Global sensitivity analysis and subset selection in heart rate modeling","2013-02-19 15:00:00","2013-02-19 15:50:00","SAS 4201","Mette Oufsen",NULL,"NC State","NA Seminar",NULL,"Many modeling studies aiming at predicting biological phenomenastruggle with finding adequate solutions of the inverse problem,estimating adequate model parameters that allow prediction of observeddynamics. Data used for parameter estimation may be sparse, moreover,biological processes giving rise to observed system description maynot be known, making it difficult to develop an adequate model. Inthis talk we mainly address the first question, how given a model andavailable data to identify a set of parameters that can be estimated.Since the model used is nonlinear, and parameter constraints not welldefined, we have chosen to estimate parameters using global techniquesbased on analysis of underlying parameter sensitivities predicted bydifferentiating the model output with respect to the parameters.Global sensitivities are computed using simple integration of localsensitivities over the space of allowed parameter values. This is doneby quadrature using Sobol-sequences for selection of nodes. We willdemonstrate a simple yet powerful approach to selecting intervals forparameter values. Based on the global sensitivities subset selectionis carried out using the Structured Correlation Matrix method and theOrthogonal Sensitivities Method. Finally the selected subsets aretested against a simulated data set using the Delayed RejectionAdaptive Metropolis method. We illustrate the approach for globalsensitivity computation using a model predicting baroreflex regulationof heart rate. This model uses measured blood pressure as an input topredict heart rate regulation.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ifk2v4b3qvhm9u8krvga2v7jog","2013-01-07 14:57:29","2013-02-13 11:47:12"
"1357","14","Departmental Tea and Cookies","2013-01-24 15:30:00","2013-01-24 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2bqiqnp52ik08grfki0c6a6nvc","2013-01-08 10:18:00",NULL
"1359","14","Departmental Tea and Cookies","2013-01-25 15:30:00","2013-01-25 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rk7n28mouju4pmommv08g73mnc","2013-01-08 10:19:34",NULL
"1361","14","Departmental Tea and Cookies","2013-01-23 15:30:00","2013-01-23 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9ppklsdpq5nct92lncvcf719kg","2013-01-08 10:20:59",NULL
"1363","3","How many points can a curve have?","2013-01-24 16:00:00","2013-01-24 17:00:00","SAS 4201","Noam Elkies","http://www.math.harvard.edu/~elkies/","Harvard",NULL,NULL,"Diophantine equations, one of the oldest topics of mathematical research, remain the object of intense and fruitful study. A rational solution to a system of algebraic equations is tantamount to a point with rational coordinates (briefly, a ""rational point"") on the corresponding algebraic variety V. Already for V of dimension 1 (an ""algebraic curve""), many natural theoretical and computational questions remain open, especially when the genus g of V exceeds 1. (The genus is a natural measure of the complexity of V for example, if P is a nonconstant polynomial without repeated roots then the equation y^2  P(x) gives a curve of genus g _iff_ P has degree 2g+1 or 2g+2.) Faltings famously proved that if g=1 then the set of rational points is finite (Mordells conjecture), but left open the question of how its size can vary with V, even for fixed g.  Already for g=2 there are curves with literally hundreds of points is the number unbounded? We briefly review the structure of rational points on curves of genus 0 and 1, and then report on relevant work since Faltings on points on curves of given genus g=1.","dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qgoirdhuk83rcr5ieol8p1f8f0","2013-01-08 13:52:53","2013-01-24 15:04:55"
"1365","8","Causality and Algebraic Geometry","2013-01-25 11:00:00","2013-01-25 12:00:00","SAS 4201","Andrew Critch","http://www.acritch.com/","UC Berkeley","Seth Sullivant",NULL,"Science, and perhaps all learning, is the problem of inferring causal relationships from observations. It turns out that algebraic geometry can provide powerful intuition and methods applicable to causal inference. The relevant theory of graphical causal models is a major entry point to the budding field of algebraic statistics, where algebraic geometry meets statistical modeling, and this talk will give an introduction to it from the perspective of an algebraic geometer. Ill introduce some conceptual tools and methods that are peculiar to algebraic statistics, and work through an example such causal inference computation using the commutative algebra software Macaulay2. At the end, Ill review some of my research on hidden Markov models and varieties, and their close connection to matrix product state models of quantum-entangled qubits.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tn6qtridr8gufkvop13d1gf0to","2013-01-09 19:46:15","2013-01-23 09:58:14"
"1367","14","Departmental Tea and Cookies","2013-01-15 15:30:00","2013-01-15 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ri34sil11apu0032djk8ovlg7c","2013-01-10 14:20:30",NULL
"1369","14","Departmental Tea and Cookies","2013-01-16 15:30:00","2013-01-16 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rqca5mfh0p0jlpastu6rto1jeo","2013-01-10 14:20:57",NULL
"1371","14","Departmental Tea and Cookies","2013-01-17 15:30:00","2013-01-17 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/64a04oejct7mhov7c839e6gq0s","2013-01-10 14:21:40",NULL
"1373","14","Departmental Tea and Cookies","2013-01-18 15:30:00","2013-01-18 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s860dk8hm3k7r4v1ih8r26l0g4","2013-01-10 14:22:50",NULL
"1375","4","Boussinesq Models and Tsunami Waves","2013-04-17 15:00:00","2013-04-17 16:00:00","SAS 4201","Dimitrios Mitsotakis","https://sites.google.com/site/dmitsot/","UC Merced","Mark Hoefer",NULL,"We consider Boussinesq systems of the Bona-Smith family for thedescription of long dispersive waves of small amplitude. Afterreviewing some recent well posedness results for specific initialboundary-value problems of these Boussinesq systems, we introduceGalerkin methods for their numerical solution. We present also newBoussinesq models with variable bottom and we study the generation andpropagation of tsunami waves. We use a new simple and computationallyinexpensive model for the description of the sea bed displacementduring an underwater earthquake, based on the finite fault solutionfor the slip distribution under some assumptions on the dynamics ofthe rupturing process. Once the bottom motion is reconstructed, westudy waves induced on the free surface of the ocean. Anintercomparison of various approaches is performed. The developmentsof the present study are illustrated on the July 17th, 2006 Javaevent, where an underwater earthquake of magnitude 7.7 generated atsunami that inundated the southern coast of Java.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mi8baornsbe1f7asa5mn2oid3c","2013-01-10 16:59:59","2013-02-11 07:52:23"
"1377","31","Water waves, tsunamis and dispersive systems","2013-04-17 11:15:00","2013-04-17 12:15:00","SAS 4201","Dimitrios Mitsotakis","https://sites.google.com/site/dmitsot/","UC Merced",NULL,NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vea014koa5q2a3mljns6jalh1c","2013-01-10 17:27:11",NULL
"1379","4","The Mathematics of Nuclear Lattice Simulations","2013-04-03 15:00:00","2013-04-03 16:00:00","SAS 4201","Dean Lee","http://www4.ncsu.edu/~djlee3/","NC State Physics","Mark Hoefer",NULL,"My research work uses supercomputers to simulate the quantum interactions of protons and neutrons.  We study atomic nuclei, superfluid neutron gases, and other strongly correlated systems.  I give a sampling of the physics results and some problems of mathematical interest that we encounter both on the theoretical side and in computational algorithms.  I discuss the Schrodinger equation, Grassmann variables, Markov Chain Monte Carlo, determinant algorithms, and spectral convexity.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/crdan9jdbhbmn75pqsjnasb9fc","2013-01-14 10:44:13","2013-03-25 06:50:49"
"1381","22","Geometry in Music","2013-01-16 16:00:00","2013-01-16 16:50:00","SAS 2102","Bill Kranec",NULL,"NC State",NULL,"http://www4.ncsu.edu/~nreadin/sum/spring2013/011613.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/njt9ag6656etpt0i2f99n7h634","2013-01-14 11:14:21",NULL
"1385","2"," Physically inspired analysis of structured data","2013-01-18 11:30:00","2013-01-18 12:30:00","Springboard Executive Conference Room Corporate Research I 2nd floor on NC State Centennial Campus","Anil Hirani","http://www.cs.uiuc.edu/~hirani","University of Illinois","Seth Sullivant",NULL,"In the past, structuring data into matrices brought enormous computational benefits to data analysis, and new algorithms like Googles PageRank. Data can however be structured in other ways to unlock the full potential of mathematics in data analysis. One common structuring which has been exploited in recent years is in the form of graphs. For example, people in an organization can be the vertices, and emails can form the edges between them. However, graphs only include pairwise connections directly. A natural generalization to capture higher-order interactions is that of simplicial complexes. Data that lives on a simplicial complex becomes viewable as a discrete and more general version of differential forms on manifolds (a simplicial complex need not be a manifold). Modern techniques for discretization of calculus on manifolds generalize and can be brought to bear on data analysis problems on simplicial complexes. The Laplacian operator,which is a fundamental operator in physical modeling, becomes a tool for data analysis via the computation of its spectrum, and computation of Hodge decomposition and harmonic forms. These lead to potential new applications, as well as to interesting mathematical and computationalchallenges.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g21l52gekki4spg6qlj01hkq10","2013-01-17 09:52:19","2013-01-17 11:30:34"
"1389","33","Multiscale Modeling in Biology and Medicine","2013-01-29 16:00:00","2013-01-29 17:00:00","COX 306","Mark Alber",NULL,"University of Notre Dame",NULL,NULL,"A three-dimensional multi-scale modeling approach will be described for studying fluidviscoelastic cell interaction during blood clot formation, with cells modeled by subcellular elements (SCE) coupled with fluid flow sub model. Using this method, motion of a viscoelastic platelet in a shear blood flow was simulated and compared with experiments on tracking platelets in a blood chamber. It will be shown that complex platelet-flipping dynamics under linear shear flows can be accurately recovered with the SCE model [1,2]. The structural features and mechanical properties of different types of fibrin networks grown in microfluidic devices will be also described including networks formed from normal plasma with and without cells, and from plasma from a hemophilic patient [3]. The mechanical model based on the microstructures within the network will be used to calculate the bulk properties of the network.In the second half of the talk, population of bacteria P. aeruginosa, main infection in hospitals, will be shown to propagate as high density waves that move symmetrically as rings within swarms towards the extending tendrils. Biologically-justified cell-based multi-scale model simulations suggest a mechanism of wave propagation as well as branched tendril formation at the edge of the population that depend upon competition between the changing viscosity of the bacterial liquid suspension and the liquid film boundary expansion caused by Marangoni forces [4]. P. aeruginosa efficiently colonizes surfaces by controlling the physical forces responsible for expansion of thin liquid films and by propagating towards the tendril tips. Therefore, P. aeruginosa can efficiently colonizes surfaces by controlling the physical forces responsible for expansion of thin liquid films and by propagating towards the tendril tips. The model predictions of wave speed and swarm expansion rate as well as cell alignment in tendrils were confirmed experimentally.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/65o8ksotn02rgdi0v8fe2cppvg","2013-01-24 08:56:49","2013-01-24 09:36:43"
"1393","1","The Enigmatic Lost Notebook of Ramanujan","2013-09-20 16:00:00","2013-09-20 17:00:00","SAS 1102","George Andrews","http://www.math.psu.edu/andrews","Pennsylvania State University","Michael Singer",NULL,"In 1976, I visited the Trinity College Library in Cambridge to examine papers from the estate of G.N. Watson.  In one box, there was a collection of more than 100 pages written by Ramanujan.  Examination of the pages revealed that this work must have been written during the last year of his life in 1919-1920.  I dubbed this manuscript &quot;Ramanujans Lost Notebook.&quot; Up until that moment, the only information available about this time in Ramanujans life came from a single letter that Ramanujan wrote to Hardy in early 1920.  This incredible document and its quite amazing mathematics have formed a major theme in my life.  In this talk, I will discuss some of the results in the Lost Notebook and their subsequent implications.  If time allows, I will describe a few of the related non-mathematical incidents that have taken place.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/603fl3uf741gr0d5efgr0mpi7g","2013-01-26 17:58:46","2013-08-22 11:15:40"
"1395","9","Decoupling Global Drivers of Latitudinal Species Gradients with a View Towards Astrobiology  & High School and Prairie Dogs","2013-01-31 16:00:00","2013-01-31 17:00:00","Cox 306","Andrew Snyder-Beattie and Mandi Traud",NULL,"NC State Biomath",NULL,NULL,"Andrew Snyder-Beattie: Decoupling Global Drivers of Latitudinal Species Gradients with a View Towards AstrobiologySpecies diversity is highest in the equatorial regions of our planet, declining as one moves to the poles. A plurality of ecological literature suggest one of two primary drivers behind this latitudinal gradient in species richness: amount of sunlight or amount of climatically consistent area. Gliese 581 is a star that provides an unique reframing for these two hypotheses. Rather than rotating like Earth, some planets of Gliese 581 are believed to be tidally locked, meaning that only one side of the planet faces the sun at all times. To investigate these two major ecological hypotheses and to examine hypothetical biospheres on other planets, classic Lotka-Volterra competition dynamics are placed on a spherical lattice to show how both area and sunlight can influence the global distribution of species. Preliminary results suggest that area has a stronger effect than solar inputs when species diversity is controlled by simple resource competition. We discuss the implications of this result for global species patterns both on Earth and tidally locked planets.------------------Mandi Traud: High School and Prairie DogsThe use of social network theory in evaluating animal social groups has gained traction in recent years. Despite the utility of social network analysis in describing attributes of social groups, it remains unclear how comparable this approach is to traditional behavioral observational studies. Using data on Gunnisons prairie dog (Cynomys gunnisoni) social interactions from three colonies we describe social networks of each colony. We then use social network analysis techniques to find groups of prairie dogs that are more connected to each other than to the rest of the colony, social network communities. We compare these communities with social groups defined using traditional approaches and to behavioral traits on the prairie dogs within those communities. The social network communities identified were consistent with those identified by more traditional behavioral approaches. However, fine-grained social sub-structuring was revealed only with social network analysis. When comparing the social network communities to the prairie dog behavioral traits we found individuals within communities were more similar to each other. However, the traits that were similar among individuals within communities varied among colonies.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8e9tjgdftrnil3ic4s8iq2bao8","2013-01-27 19:03:04","2013-01-28 11:01:50"
"1397","26","Sliding Mode Control Based on an Inverse Compensator Design for Hysteretic Smart Systems","2013-01-28 16:00:00","2013-01-28 17:00:00","SAS 4201","Jerry McMahan",NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/57q9idjapimqtcs6i81od0tnk8","2013-01-28 12:09:18",NULL
"1399","9","Mitochondria's Revenge: The Role of Oxidative Stress in Type 2 Diabetes","2013-02-07 16:00:00","2013-02-07 17:00:00","Cox 306","Erica Graham",NULL,"NC State Dept of Mathematics",NULL,NULL,"Type 2 diabetes is a worldwide epidemic with many complex mechanisms of its long-term pathogenesis.  An imbalance between glucose and insulin are characteristic of the disease, wherein insulin-responsive cells are unable to meet metabolic demands, termed insulin resistance, and glucose dysregulation ensues.  The progression of insulin resistance, which persists for decades, is itself incompletely understood, though several mechanisms have been proposed.  We focus on feedback between skeletal muscle mitochondria and oxidative stress to explain the metabolic dysfunction in insulin resistance.  We utilize deterministic and stochastic methods to model long-term intracellular dynamics, and we find that overnutrition can indeed generate the oxidative stress-mediated mitochondrial defects that, through positive feedback, inhibit normal cellular responses to insulin.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/54i23miq1f9h52g4otqjspccm4","2013-01-28 12:36:08",NULL
"1401","22","Fractals, the Chaos Game, and the Contraction Mapping Theorem","2013-01-30 16:00:00","2013-01-30 16:50:00","SAS 2102","Nathan Reading",NULL,"NC State",NULL,"http://www4.ncsu.edu/~nreadin/sum/spring2013/013013.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/flc55rp1dtp4s3e40se1skvq3c","2013-01-29 13:38:59",NULL
"1403","22","Statistics without addition or division","2013-02-06 16:00:00","2013-02-06 16:50:00","SAS 2102","Ezra Miller","http://www.math.duke.edu/~ezra/","Duke",NULL,"http://www4.ncsu.edu/~nreadin/sum/spring2013/020613.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/firipu1m5urd5d6nq40eglmioo","2013-01-29 13:40:44",NULL
"1405","31","Geometry of Conservation Laws","2013-03-13 11:15:00","2013-03-13 12:15:00","SAS 4201","Michael Benfield",NULL,"NC State Mathematics Graduate Student",NULL,NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u9a11d0bvq8cdmtidrg0bfckdk","2013-01-29 15:38:12",NULL
"1407","6","Reduced Stochastic Models for Filtering Turbulent Dynamical Systems  ","2013-02-05 15:00:00","2013-02-05 16:00:00","SAS 4201","John Harlim","http://www4.ncsu.edu/~jharlim/","NS State",NULL,NULL,"Fundamental issues in advancing real-time filtering problems are model errors even when expensive high-dimensional global weather forecasting models are used. For example, the modern operational weather models poorly reproduce the tropical observational records even with 10^9 state variables this long-standing issue hinders the global weather model forecasting skill to improve from weekly to monthly, as reported in a recent article in the World Meteorological Organization bulletin. In this talk, I will discuss a class of computationally fast reduced stochastic models to help filtering. I will try to convince you that such a filtering approach can provide practical guidelines to improve estimation of moisture coupled tropical waves. Furthermore, Id like to use mathematical theory to convince you that one can achieve optimal filtering"" with judicious choice of reduced stochastic models.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1pu3ril3g2ibfr1vab3uco10h8","2013-01-30 09:51:46",NULL
"1409","14","Departmental Tea and Cookies","2013-01-30 14:30:00","2013-01-30 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/38lnpcre01fndrtjerr821jjr4","2013-01-30 13:34:45",NULL
"1411","23","Post Interview Topics and Joint Meetings","2013-02-01 15:00:00","2013-02-01 16:00:00","SAS 4201","Departmental Faculty",NULL,"NC State","Ralph Smith",NULL,"Youve had one or more job interviews and you may wonder what to do now.  For example, should you negotiate if you receive an offer? Is it ever okay to accept more than one offer?  What do you do if you dont hear back from an interview? These questions and others will be discussed during this weeks RTM.  We will also include feedback from the joint meetings about interviews conducted there.  This session should be of interest to all students and postdocs presently looking for a job.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q1un8s8432sam73gie68f7amfs","2013-01-31 09:58:23",NULL
"1413","4","From resolvent estimates to damped waves","2013-02-20 15:00:00","2013-02-20 16:00:00","SAS 4201","Hans Christianson","http://hans.unc.edu/","UNC at Chapel Hill","Lorena Bociu",NULL,"In this talk I will describe some problems in geometric control theory, specifically for the damped wave equation.  The rough question one might pose is ""where do you put your hand on a drum to stop it from vibrating?""  The answer of course depends on the geometry of the drum.  I will then present a recent ""black-box"" type result with E. Schenck, A. Vasy, and J. Wunsch, in which we explore what happens if your damping is not perfect.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5cs0gqovo88eviggoc46eftgos","2013-02-01 18:21:52",NULL
"1415","2","Applied and computational metric geometry","2013-02-06 16:00:00","2013-02-06 17:00:00","SAS 4201","Facundo Memoli","http://cs.adelaide.edu.au/~memoli/","University of Adelaide","Seth Sullivant",NULL,"In many problems arising in the computational sciences datasets come already equipped with some underlying notion of similarity. Metric geometry thus provides a natural point of view which is applicable in the realm of non-smooth data. The underlying idea is to regard datasets as metric spaces, or metric measure spaces (metric spaces enriched with probability measures), and then, crucially, at the same time regard the collection D of all datasets as a metric space in itself. The Gromov-Wasserstein distance --a variant of the Gromov-Hausdorff distance based on mass transport-- provides an intrinsic metric on the collection D of all datasets. Furthermore, this  metric makes D into an Alexandrov space of non-negative curvature.In this talk I will describe the construction of the GW metric, its properties, and discuss how the representation of datasets as metric measure spaces gives rise to a number of stable invariants which are counterparts to concepts emerging in topology and differential geometry, including analogues to homology and notions of curvature that are valid beyond the smooth case.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d7qqenls6glh5r9uujvn8rlct8","2013-02-02 11:09:22",NULL
"1417","4","Morse Theory for Lagrange Multipliers","2013-03-13 15:00:00","2013-03-13 16:00:00","SAS 4201","Stephen Schecter","http://www4.ncsu.edu/~schecter/","NC State",NULL,NULL,"I will first review the (outsized) role that Morse Theory and its descendants have played in mathematics since 1950.  I will then consider the restriction of a function to a manifold that is the zero set of another function.  Using geometric singular perturbation theory, I will relate the Morse homology of the restricted function to that of its Lagrange multiplier function, which I will in turn relate to the Morse homology of a complex whose orbits are singular orbits of a slow-fast system.  The talk is thus an example of reverse applied mathematics: a technique of applied mathematics is used in pure mathematics.  This is joint work with Guangbo Xu (Princeton).","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nk7i5mmaa96ld94dhlum64ag0o","2013-02-04 08:01:58","2013-02-06 10:48:37"
"1419","14","Departmental Tea and Cookies","2013-02-06 15:30:00","2013-02-06 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6hlunm8cauor6qd38siv5ncjls","2013-02-04 08:43:20","2013-02-04 09:24:41"
"1421","9","Understanding blood pressure regulation through modeling ","2013-02-14 16:00:00","2013-02-14 17:00:00","Cox 306","Adam Mahdi","http://www4.ncsu.edu/~amahdi/","NC State Dept of Mathematics",NULL,NULL,"Understanding the cardiovascular control system is crucial for gaining more insight into the physiology not only for the healthy individual, but also to  detect pathologies. The main role of the cardiovascular system is to maintain adequate oxygenation of all tissues. This is achieved by maintaining blood flow and pressure at a fairly constant level. To accomplish the transport, a number of control mechanisms are imposed regulating vascular resistance, compliance and frequency. An important contributor to the cardiovascular control is the baroreflex (or baroreceptor reflex), which uses specialized neurons, called baroreceptors, that are activated using mechano-sensitive sensors located in the aortic arch and carotid sinuses. These neurons are stimulated by changes in blood pressure and contribute to short-term regulation of vascular efferents including: heart rate, cardiac contractility, and vascular tone. Baroreceptor dynamics have been studied since 1950s. Unfortunately most models are of little or no biological motivation. In this presentation, we will discuss various mathematical techniques and approaches used in the past to describe baroreceptors. Finally, we propose a new, biologically motivated model, which reflects all known static and dynamic properties of the baroreceptors including: saturation, threshold, PED (post-excitatory depression), adaptation and rectification.This work is a part of the bigger project called ""The Virtual Physiological Rat Project"" (http://virtualrat.org/), with objective to build and simulate the cardiovascular functions of the rat and build a validated computer models across rat strains. The ultimate goal of using mathematical and computer models is to predict the physiological characteristics of not yet realized combinations, derive those combinations in the lab, and then test the predictions.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/atiabe2va9aj7c52hdorutath4","2013-02-04 09:06:23",NULL
"1423","3","The local EynardOrantin recursion in singularity theory","2013-02-25 15:00:00",NULL,"SAS 4201","Todor Milanov","http://member.ipmu.jp/todor.milanov/","IPMU, University of Tokyo",NULL,NULL,"The Eynard-Orantin recursion was discovered first in the settings of matrix models. It turns out that the recursion holds in much greater generality. It is turning into a very powerful tool for computing the correlation functions in various Quantum Field Theories (QFT). My plan is to explain what the recursion is in general and how it enters in a particular class of QFTs known as the Landau-Ginzburg model.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tqmombmkieec1ui0snapau70lo","2013-02-05 10:07:57","2013-02-19 13:29:04"
"1425","3","Bad semidefinite programs: they all look the same","2013-03-25 15:00:00","2013-03-25 16:00:00","SAS 4201","Gabor Pataki","http://www.unc.edu/~pataki/","Chapel Hill","Alex Fink",NULL,"Semidefinite Programming (SDP) is the problem of optimizing a linear objective function of a symmetric matrix variable, with the requirement that the variable also be positive semidefinite. SDP is a much more general optimization problem than linear programming, with applications ranging from engineering to combinatorial optimization, while it is still efficiently solvable.   Duality theory is a central concept in SDP, just like it is in linear programming, since in optimization algorithms a dual solution serves as a certificate of optimality. However, in SDP, unlike in LP, rather fascinating pathological phenomena occur: nonattainment of the optimal value, and positive duality gaps between the primal and dual problems.   This research was motivated by the curious similarity of pathological SDP instances appearing in the literature. We prove an exact, combinatorial type characterization of badly behaved semidefinite systems, ie. show that -- surprisingly -- all bad SDPs look the same. We also prove that all badly behaved semidefinite systems can be reduced to a minimal such system with just one variable, and two by two matrices in a well defined sense. Our characterizations imply that recognizing badly behaved semidefinite systems is in NP and co-NP in the real number model of computing.   For general conic linear programs we give a geometric sandwich theorem to characterize badly behaved systems, of which the SDP result is a special case.   The talk will be self-contained, and not assume any previous knowledge of semidefinite programming, or duality theory.","dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rlm9umqv4fpj5ub0sa2pp9cl10","2013-02-05 13:55:41","2013-03-16 13:30:08"
"1427","14","Town Hall Meeting with the Chancellor","2013-02-14 15:00:00","2013-02-14 16:00:00","SAS 2203",NULL,NULL,NULL,NULL,NULL,"Chancellor Woodson will visit PAMS to discuss the latest plans for the new College of Sciences and the rest of the university.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8oa0q6tfdbfkpd8d197gaq70o4","2013-02-05 14:39:33","2013-02-11 11:23:10"
"1429","27","Triangle Lectures in Combinatorics Triad edition","2013-02-09 09:00:00","2013-02-09 17:00:00","Wake Forest University Winston Salem NC Manchester Hall Room 016",NULL,NULL,NULL,NULL,"http://www.math.ncsu.edu/TLC/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/et2rph2lppgr16i6kdn8451lvo","2013-02-05 15:11:26","2013-02-05 15:12:04"
"1431","3","Doubly universal Grobner bases","2013-04-15 15:00:00",NULL,"SAS 4201","Jenna Rajchgot","http://www.math.cornell.edu/~jrajchgot/","University of Michigan","Seth Sullivant",NULL,"A universal Grobner basis of an ideal in a polynomial ring is a finite set of polynomials which is a (non-reduced, non-minimal) Grobner basis for every monomial order. In this talk, Ill explain a way to generalize this notion from an ideal in a polynomial ring to an ideal sheaf defining a universal family. Ill then discuss how one can use this doubly universal Grobner basis to study torus orbits in Hilbert schemes. This is joint work with Mathias Lederer.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dlb1tbjpof71sbmj256d600cbg","2013-02-06 18:49:13","2013-04-04 15:14:33"
"1433","22","Can You Measure the Speed of Sound Using a Beer Bottle?","2013-02-13 16:00:00","2013-02-13 16:50:00","SAS 2102","Ralph Smith","http://www4.ncsu.edu/~rsmith/","NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/021313.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qijs4evudso0ac752p92h1o4dg","2013-02-08 11:02:04","2013-02-08 11:03:12"
"1435","26","Spreading and bistability of droplets driven by thermocapillary forces","2013-02-11 16:00:00","2013-02-11 17:00:00","SAS 4201","Josh Bostwick",NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/65g7vm2flcimgsinns41365hos","2013-02-08 13:50:07","2013-02-11 10:11:20"
"1437","3","Towards a lifting of representations of finite reductive groups","2013-03-11 15:00:00",NULL,"SAS 4201","Jeff Adler","http://www1.american.edu/faculty/jadler/","American University",NULL,NULL,"The problem of understanding base change for p-adic groups forces one to consider a certain generalization of base change for finite groups.   For example, suppose that G is a reductive group over a finite field k, and Gamma is a group of k-automorphisms of G.  Under mild hypotheses, the connected part H of the group of fixed points is reductive, and there is a natural lifting of (packets of) representations of H(k) to (packets of) representations of G(k).  I will give an introduction to base change, and give a partial description of this generalization.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/om9k22tjh0be2madf6kdag5f14","2013-02-09 20:58:41","2013-02-15 09:16:53"
"1439","19","An introduction to Metaphylogenomics ","2013-02-11 16:00:00","2013-02-11 17:00:00","SAS 2229","Ruth Davidson","www4.ncsu.edu/~redavids",NULL,NULL,NULL,"This talk will give a birds eye view of contemporary large-scale phylogeny estimation methods intended for an audience with no previous knowledge of the field.  Phylogenetic methods estimate the common evolutionary history of a group of species using biological data.  The study of phylogeny has created an interface between computer science, biology, and the mathematical disciplines of combinatorics, algebraic geometry, and commutative algebra.  New methods in genome sequencing have made the development of phylogenetic estimation methods that successfully process large data sets of critical importance.  Metaphylogenomics is an approach to this problem that incorporates existing algorithms into iterative methods that estimate sequence alignments and phylogenetic trees simultaneously.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qsbvrivsavhgs1d2hlh7ifoei4","2013-02-09 21:43:26","2013-02-10 10:02:02"
"1443","19","Combinatorics of CAT0 cubical complexes ","2013-02-25 16:00:00","2013-02-25 17:00:00","SAS 2229","Rika Yatchak",NULL,NULL,NULL,NULL,"Given a reconfigurable system X, such as a robot moving on a grid or a set of particles traversing a graph without colliding, the possible positions of X naturally form a cubical complex S(X). When S(X) is a CAT(0) space, we can explicitly construct the shortest path between any two points, for any of the four most natural metrics: distance, time, number of moves, and number of steps of simultaneous moves. Well go through the basic definitions on reconfigurable systems and CAT(0) spaces. Then well talk about the inherent combinatorial structure of CAT(0) cubical complexes via a few concrete examples.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q58dp5jpvk4pdnqr76tsu2q65c","2013-02-10 10:00:35","2013-02-20 17:13:48"
"1445","14","Departmental Tea and Cookies","2013-02-13 14:30:00","2013-02-13 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6dfm3v0i59ksgab6hsh1v0rpeo","2013-02-11 08:58:11",NULL
"1447","24","MGSA Cookie Contest","2013-02-14 11:30:00","2013-02-14 13:30:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,"Valentines day is upon us, so to celebrate, MGSA is hosting its annual Cookie Contest on Thursday February 14th! Anyone can enter the contest by bringing your favorite dessert for everyone to taste! Note that you neednt bring cookies if you have another recipe in mind. There will be prizes for the winners! The contest will take place on Thursday 2/14 from 11:30 am to 1:30 pm in SAS 4th floor lounge. Please bring your dessert to the lounge by 11:30 am, or you can drop them off with Mami or Kristy in SAS 3263 by 11:00 am. Then, everyone is welcome to taste the sensations from 11:30 to 1:30!","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ag6jqgbqrtvd6fnul55ufojstc","2013-02-11 10:13:08","2013-02-12 08:26:23"
"1449","14","Reception","2013-02-14 14:15:00","2013-02-14 15:00:00","SAS Atrium",NULL,NULL,NULL,NULL,NULL,"This reception will be an opportunity for faculty and staff of the new College of Sciences to begin to get to know each other. To ensure an accurate refreshment count, please rsvp at http://bit.ly/14Nga28 by February 11.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u8jeg0lc6id1eknnu5tfvcospo","2013-02-11 11:05:25","2013-02-11 11:22:53"
"1451","19","Fermionic Realization of Toroidal Lie Algebras","2013-02-18 16:00:00","2013-02-18 17:00:00","SAS 2229","Chad Mangum","http://www4.ncsu.edu/~cmangum2/",NULL,NULL,NULL,"The structure of simple, finite dimensional Lie algebras has been well established since (at least) the 1970s. Affine Kac-Moody Lie algebras, developed independently by Victor Kac and Robert Moody, are natural generalizations to the infinite dimensional case, and are typically realized as central extensions of loop algebras. However, there is another realization established by Igor Frenkel and Alex Feingold which represents them via quadratic terms of certain Clifford algebras. A further generalization of affine algebras exists known as toroidal Lie algebras, which are central extensions of multi-loop algebras. The goal of my current work is to realize the so-called twisted 2-toroidal sl(2n) with a similar realization to that of Frenkel/Feingold. Background and progress of that work will be discussed, as well as potential future work.This talk is intended to be somewhat informal and interactive questions and comments throughout will be welcomed.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3e1j1fpkea3a5c7k4klb2ta1as","2013-02-14 06:30:13",NULL
"1453","22","Knots, Surfaces and the Fundamental Group","2013-02-20 16:00:00","2013-02-20 16:50:00","SAS 2102","Nathan Reading",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/022013.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rl90jgcfki3rjf7e3nqnvvc8m0","2013-02-14 11:09:43","2013-02-14 11:10:14"
"1455","26","Stochastic vs. Deterministic Models for Systems with Delays","2013-02-18 16:00:00",NULL,"SAS 4201","Jared Catenacci",NULL,NULL,NULL,NULL,"We consider population models with nodal delays which result in dynamical systems with delays. For small population models the appropriate models are discrete stochastic systems with delays. We consider these delay systems and present new theoretical and computational results for such systems. In particular, we summarize results on the effects of different types of delays (a fixed delay and a random delay) on the dynamics of stochastic system as well as their relationship with each other in the context of a just-in-time network model. In addition, we numerically explore the corresponding deterministic approximations for the stochastic systems with these two different types of delays.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qi6qgucttgssi57uq88do82hk4","2013-02-15 10:32:13",NULL
"1457","6","Newtons Method for Monte Carlo  Based Residuals","2013-04-30 15:00:00","2013-04-30 15:50:00","SAS 4201","Tim Kelley","http://www4.ncsu.edu/~ctk/","NC State","NA Seminar",NULL,"We analyze the behavior of inexact Newton methods for problems wherethe nonlinear residual, Jacobian, and Jacobian-vector products arethe outputs of Monte Carlo simulations. We propose algorithms whichaccount for the randomness in the iteration, develop theory forthe behavior of these algorithms, and illustrate the resultswith an example from neutronics.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/avbe213cm3oln14p53qf98c5es","2013-02-15 12:38:54","2013-04-05 09:13:05"
"1459","1","Phylogenetic algebraic geometry","2013-11-07 16:00:00","2013-11-07 17:00:00","SAS 1102","Seth Sullivant","http://www4.ncsu.edu/~smsulli2","NC State Distinguished Faculty Colloquium ",NULL,NULL,"The main problem in phylogenetics is to reconstruct evolutionary relationships between collections of species, typically represented by a phylogenetic tree. In the statistical approach to phylogenetics, a probabilistic model of mutation is used to reconstruct the tree that best explains the data (the data consisting of DNA sequences from genes appearing in all species being analyzed). In algebraic statistics, we interpret these statistical models of evolution as geometric objects in a high-dimensional probability simplex. This connection arises because the functions that parametrize these models are polynomials, and hence we can consider statistical models as algebraic varieties. The goal of the talk is to introduce this connection and explain how the algebraic perspective leads to new theoretical advances in phylogenetics, and also provides new research directions in algebraic geometry. The talk material will be kept at an introductory level, with background on both phylogenetics and algebraic geometry.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/e0nlhv632kuo8cvcmie9oo4mq0","2013-02-17 11:06:19","2013-10-22 13:38:02"
"1461","1","Shock Waves!","2013-11-21 16:00:00","2013-11-21 17:00:00","SAS 1102","Michael Shearer","http://www4.ncsu.edu/~shearer/home0.html","NC State Distinguished Faculty Colloquium",NULL,NULL,"Shock waves appear in many natural contexts. Mathematically, they are discontinuous solutions of nonlinear partial differential equations. In this lecture, I outline elementary aspects of the theory of shock waves, and explore their appearance in a variety of settings, both mathematical and physical. Examples are taken from my research over the last twenty years or so. The lecture will consist of a mixture of equations and pictures, making it accessible to a wide audience, from mathematicians to artists","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/7irlhij5ujklfv899r2ean1c10","2013-02-17 14:50:19","2013-11-11 13:52:20"
"1463","1","Rooks, Recurrences and Residues","2013-10-17 16:00:00","2013-10-17 17:00:00","SAS 1102","Michael Singer","http://www4.ncsu.edu/~singer","NC State Distinguished Faculty Colloquium",NULL,NULL,"There are 3968319 ways for a rook on one corner square of an 8 x 8 chess-board to reach the opposite corner square. Techniques originated by Wilf and Zeilberger allow one to write down a three term recurrence relation for R(n), the number of ways a rook can move from one corner square to the opposite corner square on an n x n chessboard. This allows one to easily find this number for arbitrary n and analyze its asymptotic behavior. When one tries to generalize these results to three-dimensional chessboards, the complexity of the Wilf-Zeilberger techniques prevents implementations from giving answers. Chen, Kauers and I have developed a technique, based on simple facts concerning residues of differentials on compact Riemann surfaces, that overcomes this bottleneck.  This talk will be an elementary exposition of this technique and its application to other combinatorial problems.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/goshpapc5tpa3c0qfbcbi6l1pk","2013-02-17 14:56:58","2013-09-27 15:06:39"
"1465","14","Departmental Tea and Cookies","2013-02-20 14:30:00","2013-02-20 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ugapuaujvh69iq329ifc1gvl4c","2013-02-18 08:46:19",NULL
"1467","9","Biology and Noise: how the moon mission figured it out","2013-02-21 16:00:00","2013-02-21 17:00:00","Cox 306","Brett Matzuka",NULL,"NC State Biomathematics Graduate Student",NULL,NULL,"In biological systems, we are trying to construct simple models to describe the underlying biological processes without becoming intractable or incomprehensible to clinicians and biologists.  Mathematicians deal with complex processes, with potentially sparse and noisy data, and construct quantitative models to help provide insight into the system.  Whether using simplified models  (logistic model, Lotka-Volterra, etc)  or more complex systems  (PBPK, molecular dynamics, genetics, etc), our goal is to fit our model to the data to obtain information on important features of the model (parameters, hidden states, etc).  Using the information from these fits, usually conditioned on a smaller cost than when we started, we conclude our study and give our results.  However, a good fit is not enough.  Relegating noises appropriately, obtaining confidence for a given estimate, and other post-hoc metrics can be utilized better to help provide further insight into a model than originally intended.  Using the Kalman filter, originally developed and used on the Apollo missions, on a cardiovascular model, we provide results and use metrics to understand the role noise plays in models.  The overall goal is to promote more thought on noise in models and estimation.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2094d2b9ieiuu9c466kre6msvc","2013-02-18 09:24:24",NULL
"1468","22","Differential Equations as Mathematical Models","2013-02-27 16:00:00","2013-02-27 16:50:00","SAS 2102","Alina Chertock",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/022713.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dl8777iqpaa89cct6bh6h8sivk","2013-02-19 16:32:46",NULL
"1470","24","Game Night","2013-02-22 21:00:00","2013-02-22 23:00:00","SAS 1216",NULL,NULL,NULL,"MGSA  AWM",NULL,"Come play games with the recruits! MGSA will be co-hosting a game night with AWM during the recruitment weekend. We will be inviting the recruits to play games and enjoy delicious snacks. We hope you can all join us and have fun with the recruits.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/obt7p6q46vkjob6s3lhvnp9ltc","2013-02-20 14:48:02",NULL
"1472","3","Rigs and Near-rigs in Algebraic Combinatorics","2013-04-22 15:00:00",NULL,"SAS 4201","Jacob White",NULL,"Texas A&M University",NULL,NULL,"We begin by studying some properties of symmetric functions, and noncommutative symmetric functions, showing that we have the following analogy: the natural numbers are to rings and abelian groups as symmetric functions are to Hopf rings and abelian Hopf algebras. To make this analogy precise, we introduce the notion of rigs in a rig category, and show how to turn these analogies into precise theorems. If time permits, we shall also show how rig categories give rise to a connection between the study of exponential generating functions, and constructions of rings. This is based on joint work with Marcelo Aguiar, and Swapneel Mahajan.","arfink","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u25cpr0n1s9orm348vmnsl4fgo","2013-02-20 15:33:40","2013-04-15 21:03:27"
"1474","19","Classification of orbifold modules using twisted modules","2013-04-15 16:00:00","2013-04-15 17:00:00","SAS 2229","Jay Elsinger","http://www4.ncsu.edu/~jrelsing/",NULL,NULL,NULL,"Given an integral lattice, L, one can construct a corresponding vertexalgebra, V, using the Heisenberg algebra and the group algebra of L.Let T be an automorphism of V. The set of T-invariant elements is anorbifold. Dong has used Zhus algebra to classify all orbifoldmodules.On the other hand, Bakalov and Kac have a way of constructing allpossible twisted modules, and I am using thier construction to see ifall the modules found via Zhus algebra can be realized as restrictedtwisted modules.I will describe both sides of this construction and present an examplecase. Only some linear algebra is necessary for this talk.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hg1cuibav6onpnrr4su16ohnlc","2013-02-20 17:15:01","2013-04-10 05:41:09"
"1476","9","The Epithelial Mesenchymal Transition: A Multiscale Approach ","2013-02-28 16:00:00","2013-02-28 17:00:00","Cox 306","Kelsey Gasior and Christian Haagaard Olsen",NULL,"NC State Biomathematics Graduate Students",NULL,NULL,NULL,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tq1knothq8ptvvvvje319ph3do","2013-02-22 10:10:53","2013-02-22 12:21:49"
"1478","26",NULL,"2013-02-25 16:00:00",NULL,"SAS 4201 ","Keri Rehm",NULL,NULL,NULL,NULL,NULL,"mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gfdv00eraeth2j3367vgurb6vk","2013-02-25 02:17:41",NULL
"1480","14","Departmental Tea and Cookies","2013-02-27 14:30:00","2013-02-27 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mjla2lfa1o3f5hsllm1k8oicm8","2013-02-25 09:24:49",NULL
"1482","22","Random Walks Everywhere","2013-03-13 16:00:00","2013-03-13 16:50:00","SAS 2102","Min Kang",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/031313.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ommj6aakemr6lkflni1t6n47hs","2013-03-04 14:11:26",NULL
"1486","2","Identifying and Extracting Treelike Structure in Complex Networks","2013-03-12 16:00:00","2013-03-12 17:00:00","SAS 4201","Blair Sullivan","http://www.ornl.gov/~b7r/","Oak Ridge National Laboratory","Seth Sullivant",NULL,"Graphs and networks are a popular way to model interactions in a wide range of applications, including data drawn from natural, social, and information sciences, and thus offer promising opportunities for interdisciplinary research. However, one significant challenge in analyzing large complex networks has been understanding the ""intermediate-scale"" structure, i.e., those properties not captured by metrics which are very local (e.g., clustering coefficient) or very global (e.g., degree distribution). It is often this structure which governs the dynamic evolution of the network and the behavior of diffusion-like processes on it. Although there is a large body of empirical evidence suggesting that complex networks have ""tree-like"" properties at intermediate to large size-scales (e.g., hierarchical structures in biology, hyperbolic routing in the Internet, and core-periphery behavior in social networks), it remains a challenge to quantify and take algorithmic advantage of this structure in many data analysis applications.In this talk, we describe recent empirical and theoretical results aimed at integrating techniques from structural graph theory (tree decompositions and minors), metric embedding theory (Gromov hyperbolicity), and scalable heuristics (core-periphery heuristics and k-core decompositions) into scalable and robust tools for &#65532extracting meaningful tree-like structure from large informatics networks. We present computational results showing the successes and failings of existing measures of tree-likeness on real world data, and discuss recent progress integrating structural information into downstream frameworks for local inference. Finally, as time permits, we will discuss new algorithms using tree decompositions to enable scalable solution of certain graph optimization problems in a high performance computing environment, and several open research problems.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u15q6spjt7upkn95camq3f5kds","2013-03-05 10:49:57",NULL
"1488","26",NULL,"2013-03-11 16:00:00",NULL,"SAS 4201","Katie Link and Kristen Rinnovatore",NULL,NULL,NULL,NULL,"Katie Link (Title: Modeling the immune response to HIV-1 and the promotion of initial acute infection.)Current HIV-1 research has been focused on the well known window period. Within this initial two weeks of infection, the time between exposure to virus and peak viremia, the host experiences an inflammatory response that is dependent upon CD4+ T-helper cells (Th1). It is known that the inflammatory response of T-cells provides target cells for viral propagation, producing the characteristic high viral load. In addition, a natural CD4+ T regulatory cell-mediated response inhibits the inflammatory response, protecting the body from irreversible damage. It is our goal to develop a stochastic model which incorporates the inflammatory response to virus as well as the nTreg-mediated regulation of Th1 recruitment, activation and proliferation.-------------------------------------Kristen Rinnovatore (Title: Modeling the Decline in the East Coast Akalat Population)With an abundance of data collected by conservation scientists, mathematical modeling can be used to make projections concerning the future of threatened species. However, without a clear experimental design, data is often insufficient to support even simple models. A discrete stage-structured matrix model governed by fecundity and survival of the species is presented and applied to data collected for the East Coast Akalat, a Kenyan bird whose population is in decline. The effect of noise and sparsity of data on the resulting accuracy of the parameter estimation of the parameters in the model is presented and discussed.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7o7721h1dq7109ionc52mgd2es","2013-03-07 13:23:12","2013-03-10 19:59:48"
"1490","9","Predicting HIV seroconversion in discordant couples","2013-03-14 16:00:00","2013-03-14 17:00:00","Cox 306","Jacob Norton",NULL,"NC State Biomath Graduate Students","Alun Lloyd",NULL,NULL,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5f309tt82gqfibn40ghagig7tk","2013-03-08 08:22:57","2013-03-13 11:42:37"
"1492","24","Pi Party","2013-03-14 11:30:00","2013-03-14 13:30:00","SAS Commons 4th floor",NULL,NULL,NULL,NULL,NULL,"Come celebrate the Pi Day (3/14) together! Pizza (pies) and dessert pies will be provided by MGSA. Everyone in Math Department is welcome. You are all encouraged to wear your favorite PI clothe to the Pi Party.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dviqqqg6eng4bhte3s8se3bmao","2013-03-10 19:59:21",NULL
"1494","14","Departmental Tea and Cookies","2013-03-12 15:30:00","2013-03-12 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vre28ikr9rjt02h1qhs6lv76ds","2013-03-11 09:49:26","2013-03-12 09:00:42"
"1498","1","Patterns of phase shift synchrony with application to binocular rivalry","2013-04-17 16:00:00","2013-04-17 17:00:00","SAS 1102","Martin Golubitsky","http://people.mbi.ohio-state.edu/mgolubitsky","Ohio State","Michael Shearer","http://www.math.ncsu.edu/events/golubitsky_coll.pdf","A coupled cell system is a network of interacting dynamical systems. Coupled cell models assume that the output from each cell is important, and that signals from two or more cells can be compared so that patterns of synchrony can emerge. This talk will discuss a result (motivated by quadruped locomotion) that classifies rigid patterns of phase-shift synchrony in time-periodic solutions of coupled cell systems and a recent application of such patterns to binocular rivalry.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/q01hqagqj5r1jojahb6ua8kud0","2013-03-12 11:21:46","2013-04-17 10:32:30"
"1500","22","Getting in Control","2013-04-17 16:00:00","2013-04-17 16:50:00","SAS 2102","Stephen Campbell",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/041713.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0e7emjdsadgl8ivfkv5329m9d4","2013-03-14 12:45:38","2013-03-15 14:54:33"
"1502","9","Using Computational Fluid Dynamics Simulations to Study Surgery and Drug Delivery in the Nasal Passages ","2013-03-21 16:00:00","2013-03-21 17:00:00","Cox 306","Julia Kimbell",NULL,"UNC Chapel Hill, School of Medicine, Dept of Otolaryngology and Head and Neck Surgery","Alun Lloyd",NULL,"Wouldnt it be extremely useful if doctors could predict the likely outcomes of nasal surgical procedures before the actual surgery?   Wouldnt it be good if topical medications like steroids and antibiotics were tailored to give you the most benefit when treating sinus disease?  These are some of the questions that researchers at the Dept. of Otolaryngology at UNC are exploring using computational fluid dynamics (CFD) techniques in models of the nasal passages that they reconstruct from CT scans.  This talk will give an overview of this research, with examples of model creation, simulation, and results analysis, and provide a glimpse of the enormous promise that CFD modeling has for optimizing treatment of upper airway concerns.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/85na4hs8afsm48e4ng993i7g4g","2013-03-15 11:50:36","2013-03-15 20:20:54"
"1504","9","Set Membership Experimental Design for Biological Systems","2013-04-11 16:00:00","2013-04-11 17:00:00","Cox 306","Cranos Williams",NULL,"Electrical and Computer Engineering, NC State ","Alun Lloyd",NULL,"Background: Experimental design approaches for biological systems are needed to help conserve the limited resources that are allocated for performing experiments. The assumptions used when assigning probability density functions to characterize uncertainty in biological systems are unwarranted when only a small number of measurements can be obtained. In these situations, the uncertainty in biological systems is more appropriately characterized in a bounded-error context. Additionally, effort must be made to improve the connection between modelers and experimentalists by relating design metrics to biologically relevant information. Bounded-error experimental design approaches that can assess the impact of additional measurements on model uncertainty are needed to identify the most appropriate balance between the collection of data and the availability of resources.Results: In this work we develop a bounded-error experimental design framework for nonlinear continuous-time systems when few data measurements are available. This approach leverages many of the recent advances in bounded-error parameter and state estimation methods that use interval analysis to generate parameter sets and state bounds consistent with uncertain data measurements. We devise a novel approach using set-based uncertainty propagation to estimate measurement ranges at candidate time points. We then use these estimated measurements at the candidate time points to evaluate which candidate measurements furthest reduce model uncertainty. A method for quickly combining multiple candidate time points is presented and allows for determining the effect of adding multiple measurements. Biologically relevant metrics are developed and used to predict when new data measurements should be acquired, which system components should be measured and how many additional measurements should be obtained.Conclusions: The practicability of our approach is illustrated with a case study. This study shows that our approach is able to 1) identify candidate measurement time points that maximize information corresponding to biologically relevant metrics and 2) determine the number at which additional measurements begin to provide insignificant information. This framework can be used to balance the availability of resources with the addition of one or more measurement time points to improve the predictability of resulting models.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4067n62hqkf0rin84htc7vnjes","2013-03-15 11:51:43","2013-04-02 20:05:53"
"1506","9","Computational Modeling of Cellular Response to Perturbation","2013-04-18 16:00:00","2013-04-18 17:00:00","Cox 306","Sudin Bhattacharya",NULL,"The Hamner Institutes for Health Sciences ","Alun Lloyd",NULL,"A core set of signaling motifs embedded in larger molecular regulatory networks underlie the response of cells to physiological or environmental perturbation. I will describe some examples of quantitative modeling of cellular response with deterministic and stochastic approaches. One example concerns the suppression of differentiation of B cells in the mammalian immune system to antibody-secreting plasma cells by the environmental contaminant TCDD. Kinetic modeling of the transcriptional regulatory motifs governing B cell differentiation predicted all-or-none physiological switching from the B cell to the plasma cell state and also binary suppression of this process by TCDD. Both predictions were later confirmed in the lab. I will also discuss a simple mathematical model to compute the epigenetic landscape underlying cell fate regulation based on the kinetic interaction parameters of the underlying transcriptional circuit. Finally, I will describe ongoing work on mapping intracellular toxicity pathways based on transcriptomic and genome-wide transcriptional binding data sets.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g6u6a2b2qqsp1b9kjk81kkqgo4","2013-03-15 11:52:31","2013-04-10 17:20:20"
"1508","9","Exploring cholera dynamics and transmission pathways using identifiability and parameter estimation","2013-04-25 16:00:00","2013-04-25 17:00:00","Cox 306","Marisa Eisenberg",NULL,"University of Michigan",NULL,NULL,"Cholera is a waterborne intestinal infection which causes profuse, watery diarrhea, vomiting, and dehydration.  It can be transmitted via contaminated water as well as person to person, with 3-5 million cases/year and over 100,000 deaths/year. An important public health question involves understanding the modes of cholera transmission in order to improve control and prevention strategies.  One issue of interest is: given data for an outbreak, can we determine the role and relative importance of waterborne vs. person-to-person routes of transmission? To examine this issue, we explored the identifiability and parameter estimation of a differential equation model of cholera transmission dynamics.  We developed identifiability methods based on a differential algebra approach, to establish whether it is possible to determine the transmission rates from case data (i.e. whether the transmission rates are identifiable).  Our results reveal issues with the identifiability of transmission pathways from noisy data, and show that both water and person-to-person transmission are needed to explain the observed cholera dynamics. I will also discuss some recent extensions to our identifiability work to disease dynamics more broadly, and our ongoing work modeling the cholera epidemic in Haiti using satellite remote sensing rainfall data to forecast cholera incidence.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g0j25p21hk7cql1n0gu6mr01p4","2013-03-15 11:54:10","2013-04-15 09:44:54"
"1510","3","Stability conditions and structures of Hall algebras and composition algebras","2013-04-01 15:00:00",NULL,"SAS 4201","Zongzhu Lin","http://www.math.ksu.edu/~zlin/","Kansas State University","Jing",NULL,"Given a finite quiver with loops, one can define a Hall algebra via representations of the quiver over finite fields. The composition algebra is the subalgebra generated by the simple modules attached to the vertices. Reineke uses the stability conditions for quiver representation interpreted by King and studied the structures of Hall algebras for a given stability condition. In this talk, I will focus on structures of composition algebras attached by the stability conditions. I will also discuss the use of stability conditions to construct representations of the Hall algebras.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6295aldvkd260ppqr4ft020e4o","2013-03-15 12:02:16","2013-03-20 10:23:00"
"1512","22","The Awesome Averaging Power of Heat in Geometry","2013-03-20 16:00:00","2013-03-20 16:50:00","SAS 2102","Andrew Cooper","http://www.math.upenn.edu/~ancoop/","University of Pennsylvania",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/032013.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3c522falds62e7ste83f0dt7dk","2013-03-15 14:56:47",NULL
"1516","14","Departmental Tea and Cookies","2013-03-20 15:30:00","2013-03-20 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hn814aafp1him1fa4kqd6bj44o","2013-03-18 09:47:42",NULL
"1518","14","Departmental Tea and Cookies","2013-03-26 15:30:00","2013-03-26 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ju7d17lmtu7ce3oqaho6p7n0p4","2013-03-18 09:48:28","2013-03-19 14:23:15"
"1520","14","Departmental Tea and Cookies","2013-04-04 15:30:00","2013-04-04 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/a2volnn442jdr7lvujm4nuq8uo","2013-03-18 09:49:17",NULL
"1522","21","Singularities of the Lagrangian Mean Curvature Flow","2013-03-19 15:30:00","2013-03-19 16:30:00","SAS 4201","Andrew Cooper",NULL,"University of Pennsylvania","Pang",NULL,"The mean curvature flow is the downward gradient of the areafunctional on sub manifolds. If the ambient manifold isKahler-Einstein and the initial sub manifold is Lagrangian, thensub manifold remains Lagrangian as long as the flow exists. Startingfrom compact initial data in complex Euclidean space, the flow mustencounter a singularity.We will describe how to model the developingsingularity with a smooth Lagrangian mean curvature flow. In the typeII (slow-forming or scale-breaking) case, the Liouville and Maslovclasses of this smooth model vanish. The vanishing of these classescan be used to understand the formation of the singularity, especiallyif the initial data are zero-Maslov or monotone.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/atcnicf9oum68taojn4cin02n0","2013-03-18 13:05:19","2013-03-19 09:25:19"
"1524","21","Multiscale Modeling of Bacterial Swarming","2013-03-26 16:00:00","2013-03-26 17:00:00","SAS 4201","Mark Alber",NULL,"University of Notre Dame",NULL,NULL,"Treatment of a broad spectrum of human health issues, ranging from lethal infections from opportunistic pathogens such as those in cystic fibrosis patients, to catastrophic failure of prosthetic implants, could improve with a greater understanding of biofilm formation. Among the biofilm development steps for which we lack understanding is the ability of bacteria to first colonize host surfaces. Bacterial swarming motility has been shown to be crucial to biofilm formation. Many bacteria can rapidly traverse surfaces from which they are extracting nutrient for growth by generating flat, spreading colonies, called swarms because they resemble swarms of insects.M. xanthus, a common soil bacteria that is studied in part for the high level of social coordination, regularly reverse direction of their motion and organize into single layers of small clusters and large rafts of cells at the edge of a spreading swarm. Coupled multiscale model and experimental bacteria tracking will be used in this talk to demonstrate how the flexibility and adhesion between cells as well as cell reversals result in bacteria effectively colonizing surfaces. A connection will be described between a microscopic one-dimensional stochastic model of reversing non overlapping bacteria and a macroscopic nonlinear diffusion equation describing the dynamics of cellular density. Existence of different classes of solutions of nonlinear diffusion equations will be also discussed.In the second half of the talk, P. aeruginosa, which is an opportunistic pathogen responsible for both acute and persistent infections in susceptible individuals, as exampled by those for burn victims and people with cystic fibrosis, will be shown to propagate as high density waves that move symmetrically as rings within swarms towards the extending tendrils. Biologically-justified multiscale model consisting of stochastic cell-based submodel representing individual bacteria coupled with the thin film NavierStokes equation will be used to suggest a mechanism of wave propagation as well as branched tendril formation at the edge of the population. The model predictions of wave speed and swarm expansion rate as well as cell alignment in tendrils were confirmed experimentally.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/c25js49k5lcatk0dcen007674k","2013-03-19 14:20:00","2013-03-20 09:35:40"
"1526","4","Transient dynamics - why the present is more complicated than the future","2013-03-25 15:00:00","2013-03-25 16:00:00","SAS 2102","Stefan Siegmund",NULL,"Technische Universitaet, Dresden, Germany","Xiao-Biao Lin",NULL,"Models from e.g. fluid dynamics or systems biology often can be described by ordinary differential equations. While the long-term behavior of those models as time tends to infinity is quite well understood, the theory of transient solution behavior is still in its infancy. We present some results as well as open questions.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ikso3p238najjqoqhfflf3sjr0","2013-03-20 14:31:02",NULL
"1528","3","Phase transitions of random quasi-group codes","2013-04-19 15:00:00",NULL,"SAS 1102","Yun Fan",NULL,"Central China Normal University","Jing",NULL,"Random quasi-group codes are considered, some phase transitions of the cumulative weight enumerators of the random quasi-abelian codes are obtained, and some unsolved questions are described.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ds6ijfm1rmcafiis31auklvis4","2013-03-27 13:05:42","2013-04-03 20:23:27"
"1530","19","The Hopf Algebra of Sashes","2013-04-08 16:00:00","2013-04-08 17:00:00","SAS 2229","Shirley Law",NULL,"NC State",NULL,NULL,"A general lattice theoretic construction of Reading constructs Hopf subalgebras of the Malvenuto-Reutenauer Hopf algebra (MR) of permutations. The products and coproducts in these Hopf subalgebras are defined extrinsically in terms of the embedding in MR. The goal of this research is to find an intrinsic combinatorial description of a particular family of these Hopf subalgebras. The simplest Hopf algebra in the family has a natural basis given by permutations that I call Pell permutations. The Pell permutations are in bijection with combinatorial objects that I call sashes that is, tilings of a 1 by n rectangle with three types of tiles: black 1 by 1 squares, white 1 by 1 squares, and white 1 by 2 rectangles. The bijection induces a Hopf algebra structure on sashes. I will describe the product and coproduct in terms of sashes, and the natural partial order on sashes.","njschwar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d5iq9aeue0rrji17c602dsi43g","2013-03-27 17:31:50",NULL
"1532","3","Realizations of the three point Lie algebra","2013-04-12 15:00:00",NULL,"SAS 1102","Ben Cox","http://coxbl.people.cofc.edu/","College of Charleston","Misra",NULL,"We describe the universal central extension of the three point current algebra sl(2,R) where R=C[t,t^-1,u  u^2=t^2+4t] and construct realizations of it in terms of sums of partial differential operators.  This is joint work with Elizabeth Jurisich.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rkn346g8dm97oov22uve3teibo","2013-03-28 11:57:18","2013-04-02 10:22:58"
"1534","15","SIAM Student Chapter Meeting - Summer Opportunities","2013-04-04 11:30:00","2013-04-04 12:30:00","SAS 4201",NULL,NULL,"NC State","Will Cousins",NULL,"All graduate students are invited to the SIAM student chapters final meeting of the school year.  Lunch will be provided, and we will have a panel of NCSU students who will discuss their experiences doing research over the summer at places such as Sandia National Laboratories, New Zealand, SAS, Army Research, and at NC State through the REG.  Also, we will elect officers for the upcoming year.","wcousin","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/l8m14db394nif13ai237asa44o","2013-03-28 12:59:21",NULL
"1536","14","Awards Day","2013-04-22 16:00:00","2013-04-22 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rj17ap7memc84e5me1mat62rv4","2013-04-02 10:33:37",NULL
"1538","14","Awards Day Reception","2013-04-22 15:30:00","2013-04-22 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/k44a2ip6u5l6a3chfo8mhrql6c","2013-04-02 10:34:09",NULL
"1540","31","Mathematical Modeling in Aeroelasticity","2013-04-10 11:15:00","2013-04-10 12:15:00","SAS 4201","Justin Webster",NULL,"Oregon State University","Lorena Bociu",NULL,NULL,"lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ust9ntdj6hs0on3rajn3i3iqc4","2013-04-02 13:19:05",NULL
"1542","4","PDE Systems in Aeroelasticity: Flow-Plate Interactions","2013-04-11 15:00:00","2013-04-11 16:00:00","SAS 4201","Justin Webster",NULL,"Oregon State University","Lorena Bociu",NULL,"We examine a prevalent model in aeroelasticity which describes the transverse oscillations of a plate immersed in a laminar flow. The model comprises a perturbed wave equation strongly coupled to a nonlinear plate including nonlinearity in the model is essential for accuracy. For the last 50 years, this flow-plate system has been studied primarily from the numerical point of view. In particular, the key focus in aeroelasticity is the prediction and suppression of an endemic instability termed flutter, wherein the structures natural vibrational modes couple with the aerodynamic load.Recent advances over the last 15 years in the theory of nonlinear plates have allowed us to consider the system from the infinite dimensional point of view, making the flow-plate system amenable to semigroup, control theoretic, and long-time behavior analyses. In this talk we discuss the key physical parameters in the analysis: the plate thickness and the unperturbed flow velocity. Both of these parameters are critical in determining the properties of the dynamics. We will (1) present key well-posedness results and (2) discuss the existence of a global attractor for the system and its properties (ultimate compactness and finite dimensionality of trajectories). We also discuss how, in the most &quot;physical&quot; configurations, the flow provides a stabilizing effect on the plate dynamics in the absence of mechanical or frictional damping.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jb6rtccblullm1bmaskc3lefs4","2013-04-02 13:20:44",NULL
"1544","22","Symmetries in Mathematics and Physics","2013-04-10 16:00:00","2013-04-10 16:50:00","SAS 2102","Bojko Bakalov",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/041013.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rrr578cljf6v2t3a34d6hjvjko","2013-04-03 13:59:57",NULL
"1546","2","Phase-field Modeling of Multiphase Flow in Porous Media","2013-04-09 09:30:00","2013-04-09 10:30:00","SAS 4201","Luis Cueto-Felgueroso",NULL,NULL,NULL,NULL,"Multiphase flow systems are often described using upscaledmathematical models, aimed at capturing the relevant flowmechanisms while keeping the problem tractable in acomputational or analytical sense. Upscaling proceduresinvoke approximations that reduce the dimensionality of themodels, write equations at a scale that is much larger thanthe typical capillary length, or both. Examples areubiquitous in fluid mechanics, from Lucas-Washburn laws ofimbibition in nanopores, to basin-scale models of CO2migration in geologic carbon sequestration.Multiphase flows through porous media are modeled withbalance laws written in terms of fluid volume fractions, orsaturations, which represent averages over a representativeelementary volume. Unlike flow of a single fluid, currenttheories of porous media flow are unable to explain complexmacroscopic phenomena observed in experiments, such asviscous and gravitational instabilities. They are alsounable to describe the impact of partial wetting in simplesystems, such as two-phase flow in a capillary tube.I will discuss a framework to model multiphase porous mediaflow at the Darcy scale, based on the phase-field approach,and leading to fourth-order equations. These models canincorporate the effect of partial wetting, and naturallylead to flow patterns that agree with experimentalobservations.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7gfmjkv857o57sr7b6jgfg562g","2013-04-04 11:29:25","2013-04-04 11:37:42"
"1548","26","Perturbations of Magnetic Solitary Waves","2013-04-08 16:00:00",NULL,"SAS 4201","Lake Bookman",NULL,NULL,NULL,NULL,"Under assumptions of high-symmetry and neglecting damping, the mathematical models for micromagnetic phenomena admit an exponentially localized, time periodic family of solutions. In experiments, however, damping is always present and over time scales of interest is significant. Allowing damping to enter as a perturbation, free parameters in this family of solutions may change over slow time. With an eye toward recent experimental results, I will discuss a general framework for determining the time evolution of these parameters.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4igh7n3er7ubkppbpi895eqea0","2013-04-07 21:01:38",NULL
"1550","21","Awards for Excellence Reception and Ceremony","2013-04-10 15:00:00","2013-04-10 16:00:00","Riddick Hearth",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/efmsb64i14epk6asdoge23rjlk","2013-04-08 11:04:37",NULL
"1552","14","Departmental Tea and Cookies","2013-04-11 15:00:00","2013-04-11 15:30:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,"The regularly scheduled Wednesday Tea has been moved to Thursday because of the Awards for Excellence reception on Wednesday.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/opcs4u02ngsqhjr9mnikhavl0c","2013-04-09 09:05:26",NULL
"1554","14","Departmental Tea and Cookies","2013-04-17 15:30:00","2013-04-17 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jm197rgu8ro07eukpdct0b2nqg","2013-04-11 15:16:57",NULL
"1556","26",NULL,"2013-04-15 16:00:00",NULL,"SAS 4201","Mami Wentworth and Dustin Kapraun ",NULL,NULL,NULL,NULL,"Mami Wentworth [Title: Model Calibration in Bayesian Framework] In this talk, we will discuss how to estimate model parameters and quantify uncertainties in parameters via a Bayesian approach. We will introduce two Metropolis algorithms, DRAM and DREAM, which estimate the distribution of parameters and construct confidence and prediction intervals. We will then use a HIV model as an example to demonstrate how these two algorithms function and compare their performance. ---------------------------------------------------------Dustin Kapraun [Title: Designing Optimal CFSE / Flow Cytometry Experiments] Flow cytometry of CFSE-labeled cells is a popular technique for studying cell proliferation. In this talk, the experimental procedure and resulting data are described, and a complex mathematical model governing cell population dynamics is briefly summarized. The problem of parameter estimation is addressed, and then the results of some preliminary investigations into optimal design of flow cytometry experiments are presented. The work to be discussed is a collaborative effort involving former NCSU Math PhD and post-doc Clay Thompson, NCSU Math professor H.T. Banks, and a group of experimental immunologists in Barcelona.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tcndfurdue3n3tqa1h987k6t90","2013-04-14 21:10:13",NULL
"1558","21","Reception for Kwangil Koh Lecture on Mathematics in Our Time Colloquium","2013-04-16 16:00:00","2013-04-16 16:30:00","SAS Atrium",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/o0t10mna4fbo1ulflkp5arpe1o","2013-04-15 09:49:03",NULL
"1560","19","Computing Persistent homology","2013-04-22 16:00:00","2013-04-22 17:00:00","SAS 2229","Harish Chintakunta",NULL,"NCSU ",NULL,NULL,"Homology and persistent homology have seen a multitude of applications recently in data analysis and signal processing. Presistent homology may be viewed as a generalization of multi-scale clustering to higher order topological features. A filtration on a Simplicial complex induces a sequence of homology groups (we will restrict ourselves to field coefficients, and hence vector spaces) and linear operators between them. Such a sequence can be written as a direct sum of sequences with one dimensional spaces with corresponding restrictions on the linear operators. Such a decomposition is the output of the persistence homology algorithm. I will present a simple and fast algorithm due to Carlsson and Zomorodian to compute such a decomposition.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d2f96v6kre0tq27k6dpaod8ftc","2013-04-16 09:34:16",NULL
"1562","19","Isomorphy Classes of Inner-Involutions of SOn,k,beta","2013-04-29 16:00:00","2013-04-29 17:00:00","SAS 2229","Robert Benim",NULL,"NC State",NULL,NULL,"In this talk, we show a characterization of the isomorphy classes of the inner involutions of So(n,k,beta) for n  2, where beta is any non-degenerate symmetric bilinear form. We can use these results to provide a full classification of the isomorphy classes of inner involutions of So(n, R) and So(n,C), and a partial classification in many other cases. Currently, the classification for other fields, k, and other symmetric bilinear forms, beta, is more complete in the case where n is odd.","njschwar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rlad8hp4pu0nnu77j32iec3a3c","2013-04-17 16:09:04","2013-04-17 16:12:18"
"1564","14","Undergraduate Research Presentations","2013-04-23 16:00:00","2013-04-23 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,NULL,"1.  JORDAN GOWER Title : MathemagicAbstract :  Many card tricks rely on mathematical topics such as universal cycles, combinatorics, group theory, and analyzing patterns. Using results from the various fields, we are able to invent tricks that have surprising outcomes, but are mathematically predictable. Several different types of tricks, and the mathematics behind them, were analyzed, and then expanded. We will demonstrate three tricks, and discuss variations and why they work. -------------------------------------------------------------------------------------2. WILLIAM OAKLEY Title :  ODEs and Optimization Abstract :  Consider an ODE $u = f(u)$, where $f:R^n to R^n$ is continuous, in a domain defined as the subset of $R^n$ where a given set of constraints take non-positve values.  We ask the following questions: what method can we use to force the solution to the ODE to stay in the domain? and is there a unique solution to the problem when this method is used?  Of course, there are many ways to keep the solution in the domain, but the method we will discuss involves the natural idea of taking as our solution the projection of $u$ onto the point of the boundary closest to $u$ when $u$ leaves the domain.  Interestingly, with this method we end up maximizing the antiderivative of $f(u)$ such that the constraints are satisfied, implying that the antiderivative of $f(u)$ must satisfy the Kuhn-Tucker conditions, which are necessary conditions for a max/min.  By modifying $f$ using the Lagrange Multipliers provided by KT conditions, we obtain a new ODE $u = Circf(u)$ that does indeed stay in the domain.  In other words, the KT conditions allow us to change the vector field $f(u)$ and examine the solution to a new ODE with this new vector field emphinstead of considering the behavior of a modified solution to the original ODE.  In this talk, we will try to understand the new ODE $u = Circf(u)$ by exploring its well-posedness properties in particular, we will discuss how existence of the solution can be established by extending the intuitive idea of projecting the solution onto the boundary, why we should expect the solution to be unique, and the issues that must be overcome when considering multiple constraints as opposed to one constraint. -------------------------------------------------------------------------------------3.  SEAN PLUMMERTitle :  Stochastic Modeling of Wolbachia-Infected MosquitoesAbstract :  Wolbachia based control strategies have been suggested as an alternative to the costly and ineffective traditional vector control for Aedes aegypti, a carrier of the mosquito-borne virus dengue fever. We develop a continuous time stochastic model for the spread of Wolbachia infected mosquitoes through a wild population. A particular aspect of interest is probability of fixation and average time to fixation for various release rates and sizes. -------------------------------------------------------------------------------------4. CALEB WEAVERTitle :  Image Rectification through Removing Projective and Affine DistortionAbstract : Not available.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vrr2cmm8u0qpv89sk25c90t85g","2013-04-22 08:51:46",NULL
"1566","14","Undergraduate Research Presentations","2013-04-24 16:00:00","2013-04-24 17:00:00","SAS 2102",NULL,NULL,NULL,NULL,NULL,"1.  ALEX CHIN Title :   Probabilistic Interpretation of Evolution TimesAbstract :   A common criticism of the Darwinian theory of evolution is based on the amount of time required for mutations to generate the species complexity that is observed today.  Simple evolutionary models require exponential numbers of mutations, but such models disregard the basic facts of natural selection.  We analyze a model that addresses this criticism and shows that only logarithmic numbers of mutations are required.  Furthermore, we propose a probabilistic interpretation of this model that can be generalized and briefly discuss the biological implications. -------------------------------------------------------------------------------------2.  ETHAN LOCKHART Title :   A Preisach Model for the hysteresis and thermal relaxation of Lead Zirconate Titanate. Abstract :  A system exhibits hysteresis when there exists a nonlinearity in the response of the system to outside stimuli. More specifically, the systems future state depends on the current state and history of the system. We consider the hysteresis exhibited by lead zirconate titanate (PZT) when placed within a varying electric field. PZT is a piezoelectric material, so both its strain and polarization will show hysteresis. These two properties also experience thermal relaxation when the external electric field is held constant. Due to internal thermal fluctuations, the system will relax to an equilibrium state. Given data on the polarization of PZT under an electric field, we model the resulting hysteresis using a variation of the Classic Preisach Model, and we model the thermal relaxation by treating the thermal fluctuations as a stochastic noise superimposed on the constant external electric field.  -------------------------------------------------------------------------------------3.  JOSEPH MURRAY Title :  Beating the Oddsmakers -- Modifying Sports Rating and Ranking Methods to Improve Predictive SuccessAbstract :  The topic of rating and ranking sports teams has risen in significance since the inception of the Bowl Championship Series, with large amounts of fame and fortune awarded to those football teams which are selected (based on rankings) to compete in postseason bowl games. Rankings are determined, among other things, by computer ranking systems which utilize topics from Linear Algebra to calculate unbiased rankings based on team performance in a given season. Additionally, these ranking methods can be used to predict winners of games by assuming that a high ranked team will beat the teams ranked below it. I analyzed the predictive accuracy of several popular ranking methods, with a focus on determining which factors of a ranking method aid in accurate predictions. I used sports data from the 2012-2013 NCAA Division I college basketball season as my input and found that the Colley method was the most successful with a natural predictive accuracy of 76.39%. I also found that, against intuition, modifying the Colley method resulted in reduced predictive accuracy however, modifying other methods resulted in higher predictive accuracy. Throughout my research, the one factor that most often improved predictive accuracy was the inclusion of a cap on margin of victory, with noticeable improvements in both an Offense-Defense model and an Elo-based method. These results imply that the predictive success of a ranking method can vary depending on the method, and that no sole component will always increase or decrease predictive success. -------------------------------------------------------------------------------------4.  JOHN NARDINI Title :  Effects of reparameterization on the inverse problem Abstract :  Inverse problems are a commonly-used procedure to fit mathematical models to a given data set. Here we consider the effects on the inverse problem when equivalent mathematical models with different parameterizations are used. Covariance tables will first be estimated in order to predict the correlation of each mathematical model, followed by the construction of certain 2-dimensional confidence ellipsoids on noisy data. This method will be tested on two well known models: the spring-oscillator system and the logistic model.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ug77vgup51br0csaaf68s1j1rk","2013-04-22 08:52:42","2013-04-23 15:19:17"
"1568","14","Retirement Reception for Dr. Fauntleroy and Dr. White","2013-04-24 15:00:00","2013-04-24 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/47ejiudja8j0kn2qokqb32oqjs","2013-04-23 14:06:50","2013-04-23 14:07:34"
"1570","22","Undergraduate Research Presentations","2013-04-24 16:00:00","2013-04-24 16:50:00","SAS 2102","Undergrad researchers",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/spring2013/042413.pdf",NULL,"selaw","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oocljg429vvrn92070pss38tr0","2013-04-23 15:16:16",NULL
"1572","24","Spring Pig Roast","2013-04-25 17:30:00",NULL,"SAS 2nd floor Spiral Courtyard",NULL,NULL,NULL,NULL,NULL,"MGSA is hosting its annual end-of-the-year BBQ on Thursday, April 25 at 5:30 pm. Ken Ball has volunteered to make his deliciously famous pig roast again this year! MGSA will provide the pig, a couple of good ol southern sides, and drinks. During this event, we will be holding an election for the next years MGSA executive board members. You are encouraged to bring your favorite dessert or side dish to share at the feast!","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vp87eo73k6p1tfgefi7oelk0hk","2013-04-23 15:20:19",NULL
"1574","28","AWM Elections","2013-04-29 14:00:00","2013-04-29 15:00:00","SAS 4201",NULL,NULL,NULL,NULL,NULL,"The AWM is inviting everyone who wants to get involved in this organization to come to this meeting. Men and women are welcome. We plan on electing new officers for next year and discuss possible ideas for events, as well as enjoy some snacks (possible homemade ice cream sandwiches) and take a break.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lh9bqo1ur532gt1fnaiqgojifk","2013-04-29 11:38:33",NULL
"1576","14","NC State Mathematics Graduation","2013-05-10 15:00:00",NULL,"SAS 2203",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5acqs7aajm2lvlal16c32g775o","2013-05-02 10:25:38","2013-05-09 10:59:14"
"1577","14","Frankie Stephenson Retirement Party","2013-05-13 15:00:00",NULL,"SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lmdcji1ftpd37inub8son4rs0o","2013-05-09 10:58:36",NULL
"1579","8","Maximizing the information divergence from an exponential family","2013-06-25 16:30:00","2013-06-25 17:30:00","SAS 4201","Johannes Rauh","http://personal-homepages.mis.mpg.de/jrauh/","Max Planck Institute","Seth Sullivant",NULL,"The information divergence (or KL divergence) is a natural measure of dissimilarity of two probability distributions.Although it is not an algebraic quantity, optimizing the divergence often leads to algebraic equations.  This happens, for example, when computing the closest distribution (MLE) in an algebraic statistical model to a given distribution.  In my talk, I want to discuss the following related problem: Given an exponential family E, which distributions have the largest divergence from E? The critical equations can be translated into algebraic equations. However, the obtained system of equations is ingeneral very hard to solve.  In my doctoral thesis I related this maximization problem to the maximization of anentropy-like quantity D over the boundary of a polytope, and together with F. I could show that there is a bijection between the sets of local maximizers.  On each non-trivial face of the polytope, the function D is smooth, with algebraic critical equations.  Hence, the original system of hard algebraic equations is equivalent to a family of slightly easier algebraic equations with less variables.  I give two examples that demonstrate that this reformulation is useful, even if the number of faces of the polytope is huge.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5su6dngrbbgahf9muhjm876n90","2013-06-17 16:34:04","2013-06-17 16:35:40"
"1581","4","Integrable dynamics of soliton gases","2013-09-18 15:00:00","2013-09-18 16:00:00","SAS 4201","Gennady El","http://homepages.lboro.ac.uk/~mage2/","Department of Mathematical Sciences, Loughborough University, UK","Mark Hoefer",NULL,"Nonlinear dispersive waves, while often being successfully modeled by integrable systems (KdV, NLS, ...) can demonstrate very complex behaviours calling for a statistical description characteristic of the classical turbulence theories. There has been significant growth of interest in &quot;integrable turbulence&quot; recently (see e.g. V.E. Zakharov,  Stud. Appl. Math. 122, 219-234 (2009)), partly  due to numerous observational and experimental evidence of the presence of complex, incoherent nonlinear wave regimes in physical systems well described by integrable equations. An important section of the emerging theory of turbulence in integrable systems is the mathematical theory of soliton gases initiated by Zakharov back in 1971. In this talk I will review recent (and not-so-recent) results on the structure and dynamics of soliton gases in integrable systems.  The main attention will be paid to the kinetic equation for solitons and its hydrodynamic reductions.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pm9f8tgmpf99u65mf2ilqhr2oo","2013-07-08 09:08:03","2013-08-27 09:30:04"
"1583","8","Galois groups of Schubert problems","2013-09-03 16:30:00","2013-09-03 17:30:00","SAS 4201","Abraham Martin del Campo","http://pub.ist.ac.at/~adelcampo/AbrIST/Home.html","IST Austria","Seth Sullivant",NULL,"Schubert calculus is an important class of geometric problems involving linear spaces meeting other fixed but general linear spaces. The Galois group of a problem in Schubert calculus is a subtle invariant that encodes intrinsic structure in its set of solutions.  These geometric invariants are difficult to determine in general. However, as Schubert problems can be modeled by systems of polynomial equations, we use numerical methods to study their Galois groups.  We present a Macaulay2 implementation of a numerical algorithm that solves Schubert problems. These algorithm is based on the geometric Littlewood-Richardson homotopies.  We use our implementation to study Galois groups of Schubert problems. This is joint work with Anton Leykin and Frank Sottile.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/13ggbtd689dnmi5fhib5i9c84k","2013-07-17 13:19:00","2013-08-13 19:59:45"
"1585","6","Wave Propagation in Advected Acoustics within a Non-Uniform Medium under the Effect of Gravity","2013-08-27 15:00:00","2013-08-27 15:50:00","SAS 4201","Saul Abarbanel ",NULL,NULL,"Semyon Tsynkov",NULL,"We investigate linear wave propagation in a non-uniform medium under the influence of gravity. Unlike the case of constant properties medium, here the linearized Eulers equations do not admit a plane-wave solution. Instead, we find a &quot;pseudo-plane wave.&quot; Also, there is no dispersion relation in the usual sense. We derive explicit analytic solutions (both for acoustic and vorticity waves) which, in turn, provide some insights into wave propagation in the non-uniform case.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bhd9e7ul4bsc5slee9o0uqjtqs","2013-07-26 12:41:41","2013-08-14 13:39:38"
"1587","14","Fall 2013 Math Department Meeting","2013-08-20 16:00:00","2013-08-20 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6bli2ltnnc1jsb2oem61gnftq0","2013-08-05 11:22:22","2013-08-05 11:23:37"
"1589","14","Departmental Tea and Cookies","2013-08-20 15:30:00","2013-08-20 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vipa5aphspkmdhbeptb3vv6bqk","2013-08-05 11:22:49",NULL
"1591","8","Maximum Likelihood Estimation for Data with Zeros","2013-08-27 16:30:00",NULL,"SAS 4201","Jose Rodriguez","http://math.berkeley.edu/~jrodrig/","UC Berkeley","Elizabeth Gross",NULL,"Maximum likelihood estimation is a fundamental computational task in statistics and it also involves some beautiful mathematics. The MLE problem can be formulated as a system of polynomial equations whose number of solutions depends on data and the statistical model. For generic choices of data, the number of solutions is the ML-degree of the statistical model. But for data with zeros, the number of solutions can be different.  In this talk we will introduce the MLE problem, give examples, and show how our work has applications with ML-duality.  This is a current research project with Elizabeth Gross.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u09i6ji33ee8182id9n4b4f9mg","2013-08-06 21:12:59","2013-08-26 17:26:44"
"1593","4","Traveling waves in the Gray-Scott model","2013-08-28 15:00:00","2013-08-28 16:00:00","SAS 4201","Vahagn Manukian","http://www.users.miamioh.edu/manukive","Miami University, OH","Stephen Schecter",NULL,"For a wide range of parameter values, we show that the Gray-Scott model supports a rich variety of families of traveling-wave solutions.The waves are of qualitatively different nature depending on the parameters. In certain singular limits, by using rescaled versions of the equations, we pinpoint the structure of the traveling waves. The results are anchored in geometric singular perturbation theory.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bmnqfa0ctdfstcv6p9kee8ojag","2013-08-09 16:48:37","2013-08-27 17:09:06"
"1597","8","Model Discrimination: symbolic computation with data","2013-09-17 16:30:00","2013-09-17 17:30:00","SAS 4201","Heather Harrington","http://www.maths.ox.ac.uk/people/profiles/heather.harrington","Oxford","Seth Sullivant",NULL,"In many branches of science, one is often interested in the problem of model selection: given observed data and a set of candidate models for the process generating the data, which is the best? Methods for model discrimination have been developed using frameworks that range from algebraic geometry to Bayesian computation. In this talk, I will present a procedure for deciding when a special class of polynomial dynamical systems (mass-action) is incompatible with observed data and may be useful for discarding a model framework that is not capable of producing observed behavior. The key idea uses ideas from algebraic geometry to construct a transformation of the model variables such that any set of steady states of the model under that transformation lies on a common plane, irrespective of the values of the model parameters. By employing the SVD on the transformed data, model rejection can then be performed byassessing the degree to which the transformed data deviate from coplanarity. Notably, this method is based only on model structure and is independent of kinetic parameter values, hence parameter-free. We demonstrate our method by applying it to protein signaling.   Finally, we present preliminary work that extends our method to include dynamics (i.e. time-course data), which relies on differential algebra elimination and Gaussian processes. This general framework complements conventional statistical methods in certain classes of problems, and furthermore, coplanarity can serve as a fast preprocessor for models before optimization.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2or0la356ad6f7755eof60iuk4","2013-08-15 09:50:40","2013-09-16 09:34:14"
"1601","4","Nonlinear Schrodinger systems with non-trivial boundary conditions","2013-10-02 15:00:00","2013-10-02 16:00:00","SAS 4201","Gino Biondini","http://www.math.buffalo.edu/~biondini/","Mathematics, State University of New York at Buffalo","Mark Hoefer",NULL,"Nonlinear Schrodinger (NLS) equations are universal models for the evolution of weakly nonlinear dispersive wave trains.  As such, they appear in a variety of physical contexts, from water waves to nonlinear optics, acoustics, Bose-Einstein condensation, etc.  These equations are also interesting from a mathematical point of view since in many cases they are completely integrable, infinite-dimensional Hamiltonian systems, and as such they possess a remarkably rich and surprising hidden structure.  Despite having been intensely investigated over the last forty years, these systems still offer a number of challenges.  Some of these involve the study of boundary value problems (BVPs) or problems in which non-trivial boundary conditions (BCs) are posed.  This talk will discuss a number of recent results in this area.  After a brief review about the inverse scattering transform (IST), which is the method of solution for the initial-value problem for the basic NLS equation, we will discuss various BVPs for the NLS equation on the half line.  After that, we will discuss the solution of both focusing and defocusing, scalar and vector, NLS equations with non-zero BCs at infinity.  A number of explicit soliton solutions will be discussed, as well as spectral problems for special classes of initial conditions.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/75blbfndaapscv295kim1es0cs","2013-08-16 09:18:38","2013-09-25 17:05:28"
"1605","21","Summer 2013 Math TA Workshop","2013-08-15 08:00:00","2013-08-19 17:00:00","SAS Hall",NULL,NULL,NULL,NULL,"http://www.math.ncsu.edu/events/Summer2013TAWorkshop.pdf",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6kpdiueu809209cpoli1sqmt2s","2013-08-16 11:04:15",NULL
"1607","23","Applying for Graduate Research Fellowships","2013-09-06 15:00:00","2013-09-06 16:00:00","SAS 4201","Math Department Faculty and Graduate Students",NULL,"NC State","Mansoor Haider",NULL,"A brief presentation on graduate research fellowships will be followed by Q&amp;A with faculty and graduate students experienced with the application and review process.  While the primary focus will be on the NSF Graduate Research Fellowship Program (GRFP), the basic ideas apply to other fellowship programs. The NSF GRFP is open to all graduate students who are US Citizens or permanent residents and are in either their first year or the fall term of their  second year of graduate school at the time of application.   The major application components consist of academic transcripts, 3 reference letters, 1 Personal, Relevant Background &amp; Future Goals statement, and 1 Graduate Research Plan statement.   Full details regarding the NSF GRFP can be found at:http://www.nsfgrfp.org/The deadlines this year are Nov. 5th (for applications) and Nov. 14th (for reference letters)","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/47krbc6b6lhq5ag5nvjkq321ec","2013-08-20 12:33:53","2013-08-20 17:39:26"
"1609","34","Multi-connected graphs, partial splits, and wandering taxa: representing phylogenetic uncertainty","2013-08-28 10:00:00","2013-08-28 11:15:00","SAS 4201","Benjamin Redelings",NULL,"Duke U, Dept of Biology","Seth Sullivant",NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0rs136l6g1od3hbn60s2rosg10","2013-08-21 11:45:17","2013-08-23 11:46:22"
"1611","31","Introduction to traveling waves","2013-08-28 11:15:00","2013-08-28 12:15:00","SAS 4201","Vahagn Manukian","http://www.users.miamioh.edu/manukive/","Miami University, OH",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bmubj695rmhv59g94oqd4630e0","2013-08-22 10:35:41","2013-08-23 10:26:21"
"1613","31","A Monte Carlo Algorithm for Matrix Multiplication","2013-09-04 11:15:00","2013-09-04 12:15:00","SAS 4201","John Holodnak","http://www4.ncsu.edu/~jtholodn/John_Holodnak/Homepage.html","NC State",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lv12rnfd1v2og3knv8v5j8ji5s","2013-08-22 10:41:34",NULL
"1615","31","Hydrodynamic type systems and their integrability","2013-09-18 11:15:00","2013-09-18 12:15:00","SAS 4201","Gennady El","http://homepages.lboro.ac.uk/~mage2/","Loughborough University",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3h5e0c8khq9bm34m7eh2sf66hg","2013-08-22 10:44:15",NULL
"1617","31","EM Wave Propagation through the Earths Ionosphere in Relation to Synthetic Aperture Radar","2013-09-25 11:15:00","2013-09-25 11:15:00","SAS 4201","Erick Smith","http://www4.ncsu.edu/~emsmith5/","NC State",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/4ifefatgsulbngt8skkk7ofckg","2013-08-22 10:45:39","2013-08-22 10:50:07"
"1619","31","A unified approach to boundary value problems","2013-10-02 11:15:00","2013-10-02 12:15:00","SAS 4201","Gino Biondini","http://www.math.buffalo.edu/~biondini/","State University of New York at Buffalo",NULL,NULL,"The solution of boundary value problems (BVPs) for integrable nonlinear partial differential equations (PDEs) has been a long-standing open problem.  Over the last fifteen years, a novel approach was developed by A.S. Fokas.  This approach is based on an extension of the inverse scattering transform (IST) that was developed in the 1970s to solve the initial value problem for such PDEs.  Interestingly, this approach also provides a novel and powerful way to solve BVPs for linear PDEs.  This talk will discuss the application of Fokas method for linear PDEs.  Specifically, we will look in detail at the solution of BVPs on the half line for a generic linear evolution PDE in 1 spatial and 1 temporal dimension.  Time permitting, two-point BVPs, multi-dimensional PDEs and BVPs for linear elliptic PDEs will also be discussed.","nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3eje6ssvrdobf532g8nu4sc6jc","2013-08-22 10:47:09","2013-09-30 08:33:28"
"1621","31","Numerical algebraic geometry with an application to physics","2013-10-30 11:15:00","2013-10-30 12:15:00","SAS 4201","Noah Daleo","http://www4.ncsu.edu/~nsdaleo/","NC State",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3aalpf01faid8k6olk7gcii068","2013-08-22 10:48:26","2013-09-30 08:31:46"
"1623","19","Organizational Meeting","2013-08-28 15:00:00","2013-08-28 16:00:00","SAS 1220","Organizational Meeting",NULL,NULL,NULL,NULL,"This meeting will partially set up the speaking schedule and journal club schedule for the semester.  We will choose some papers for the journal club.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5e3eqrae3mnrtmsto1n21prkmg","2013-08-22 11:58:08",NULL
"1625","3","Commutative subalgebras in Lie-Poisson algebras and their quantization","2013-10-18 16:00:00","2013-10-18 17:00:00","SAS 4201","Alexander Molev","http://www.maths.usyd.edu.au/ut/people?who=AI_Molev","University of Sydney",NULL,NULL,"For each Lie algebra g the symmetric algebra S(g) is equipped with the Lie-Poisson bracket. In the case where g is simple, Mishchenko and Fomenko (1978) produced Poisson commutative subalgebras of S(g) together with their free generators. We will give explicit constructions of maximal commutative subalgebras of the universal enveloping algebras U(g) which quantize the MF subalgebras. The construction is based upon the properties of the center of the affine vertex algebra at the critical level.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q3k5q9ar4ftvvrgrr0hn3ro0gg","2013-08-22 13:04:15","2013-10-07 20:34:34"
"1627","8","Characteristic Imset Polytope of Bayesian Networks with Ordered Nodes","2013-10-08 16:30:00","2013-10-08 17:30:00","SAS 4201","Jing Xi","http://xijing-stat.net/","NC State","Jon Hauenstein",NULL,"In 2010, M. Studeny, R. Hemmecke, and S. Linder explored a new algebraic description of graphical models, called characteristic imsets. Compare with standard imsets, characteristic imsets have several advantages: they are still unique vector representative of conditional independence structures, they are 0-1 vectors, and they are more intuitive in terms of graphs than standard imsets. After defining a characteristic imset polytope (cim-polytope) as the convex hull of all characteristic imsets with a given set of nodes, they also showed that a model selection in graphical models, which maximizes a quality criterion, can be converted into a linear programming problem over the cim-polytope. However, in general, for a fixed set of nodes, the cim-polytope can have exponentially many vertices over an exponentially high dimension. Therefore, in this paper, we focus on the family of directed acyclic graphs (DAGs) whose nodes have a fixed order.  This family includes diagnosis models which can be described by Bipartite graphs with a set of m nodes and a set of n nodes for any m, n in Z+. In this paper, we first consider cim-polytopes for all diagnosis models and show that these polytopes are direct products of simplices. Then we give a combinatorial description of all edges and all facets of these polytopes. Finally, we generalize these results to the cim-polytopes for all Bayesian networks with a fixed underlying ordering of nodes with or without fixed (or forbidden) edges.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5tkgcn4u8inak208bhgffalo54","2013-08-22 13:13:10","2013-10-07 09:07:02"
"1629","8","Goodness-of-fit testing for social network models","2013-10-29 16:30:00","2013-10-29 17:30:00","SAS 4201","Elizabeth Gross","http://homepages.math.uic.edu/~lizgross/Home.html","NC State","Jon Hauenstein",NULL,"One challenge in using statistical models for network data is the lack of standard asymptotics to assist in the development of goodness-of-fit testing.  For log-linear social network models, such as the p1 model, this challenge can be addressed by finding a Markov basis, which is analogous to finding the generating set of a toric ideal.  Such an algebraic approach has inherent computational challenges, though.  For example, for the the p1 model, symbolic computation methods fail once the number of nodes in the network is larger than 6. In this talk we will introduce the p1 random graph model, which belongs to an important and flexible class of statistical models for social networks, and suggest an alternate algorithm for goodness-of-fit testing with algebraic and combinatorial underpinnings.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kp1m6mlccam9gp4k02lotli95g","2013-08-22 13:15:26","2013-10-24 10:54:48"
"1631","26","Organizational Meeting","2013-08-26 16:00:00",NULL,"SAS 4201",NULL,NULL,NULL,NULL,NULL,"We will be having our first meeting to plan out presentation times.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6qe6l1cp8k1sd2kk1tl0du08ro","2013-08-22 14:56:49",NULL
"1633","31","HIV Vaccination Strategies","2013-10-16 11:15:00","2013-10-16 12:15:00","SAS 4201","Kaska Adoteye","http://www4.ncsu.edu/~kadotey/Home.html","NC State",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qr96c2ucnh4lgd3jartjp0kg4s","2013-08-23 08:04:29",NULL
"1635","34","Applications of Phylogenetic Invariants","2013-11-20 10:00:00","2013-11-20 11:15:00","SAS 4201","Joseph Rusinko",NULL,"Winthrop University",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mqf0mq09khmidi37n002ck27gg","2013-08-23 11:53:52","2013-11-04 08:59:05"
"1637","31","Semigroup Solutions to Initial Value Problems for the Wave and Heat Equations","2013-10-23 11:15:00","2013-10-23 12:15:00","SAS 4201","Kristina Martin",NULL,"NC State",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/so2m3pev7cne5hs55m11i47b2g","2013-08-26 08:52:38",NULL
"1639","3","Partial and false theta functions and representation theory","2013-09-23 14:30:00","2013-09-23 15:30:00","SAS 4201","Antun Milas","http://www.albany.edu/~am815139/","SUNY Albany",NULL,NULL,"Classical theta functions are known to appear in many branches of mathematics, including representation theory of infinite-dimensional Lie algebras. Another important function that was recently connected to Lie theory is the remarkable mock theta function of Ramanujan. In this talk, we show that certain incomplete theta-like series called partial and false theta functions (in a sense of Rogers) also enjoy interesting properties especially in the framework of vertex algebras and 2-dimensional conformal field theory.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/86uchl6hv3ehkiu0v5gl42i4vk","2013-08-26 11:27:10","2013-09-19 06:17:42"
"1641","34","The uncertainty of Bayesian estimation of species divergence times","2013-09-18 10:00:00","2013-09-18 11:15:00","SAS 4201","Mario dos Reis","http://people.cryst.bbk.ac.uk/~fdosr01/","University College London",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0kasflmfe4e3f5qvlt9ibt31ec","2013-08-26 12:37:39","2013-09-15 18:48:24"
"1643","14","Departmental Tea and Cookies","2013-08-28 14:30:00","2013-08-28 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sbfobn31jrcepoqubuoqtfhdm8","2013-08-26 20:26:46",NULL
"1645","4","Soft fracture: initiation and growth","2013-11-20 15:00:00","2013-11-20 16:00:00","SAS 4201","Karen Daniels","http://nile.physics.ncsu.edu/cgi-bin/webpage","Physics, NC State","Mark Hoefer",NULL,"I will describe the initiation and growth of fractures in gels close to their solid-liquid transition. In experiments, channel fractures form at the surface of the gel, driven by fluid propagating away from a central droplet. Their initiation is governed by two processes. First, surface-tension forces exerted by the droplet deform the gel substrate and break azimuthal symmetry. We model the substrate as an incompressible, linear-elastic solid and characterize the elastic response to provide a prediction for the number of fracture arms as a function of material properties and geometric parameters. Second, a thermally-activated process initiates a starburst-shaped collection of fractures corresponding to this strain-patterning.  Once initiated, the fractures grow with a universal power law $L=t^3/4$, with the speed limited by the transport of an inviscid fluid into the fracture tip. While treating the gel as a linear material correctly predicts power-law growth, we find that considering the gel to be a neo-Hookean (incompressible) gives a closer match to the experiments.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/97cvn3m1lss6ijdbb7t0olg7ak","2013-08-27 09:34:32","2013-11-11 09:25:08"
"1647","21","Triangle Lectures in Combinatorics","2013-09-21 09:30:00","2013-09-21 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,"http://www.math.ncsu.edu/TLC/",NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7bdsrd8ii1rh1rhr2mbdbmqg0o","2013-08-27 11:21:46","2013-09-02 08:35:13"
"1651","4","Asymptotic Stability for KdV Solitons in Weighted Spaces Via Iteration","2013-11-13 15:00:00","2013-11-13 16:00:00","SAS 4201","Brian Pigott","http://www.math.wfu.edu/Faculty/Pigott.html","Wake Forest University","Lorena Bociu",NULL,"We consider the KdV equation in exponentially weighted Sobolev spaces following the work of Pego and Weinstein. We show that the perturbations (weighted and unweighted) are locally well-posed in a Besov refinement of the Bourgain space $X^1,b$. An iteration argument allows us to recover the original result of Pego and Weinstein. Combining this with the $I$-method, we expect to prove asymptotic stability for the KdV solitons with initial data too rough to be in $H^1$. This is a joint work with Sarah Raynor.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/domb56haqposi7f6r0l4ga0dto","2013-08-27 13:16:22","2013-10-10 13:54:15"
"1653","4","Spectral Theory for the Robustness and Dynamical Properties of Complex Networks","2013-10-16 15:00:00","2013-10-16 16:00:00","SAS 4201","Dane Taylor","https://sites.google.com/site/danetaylorresearch/home","Mathematics, UNC Chapel Hill","Mark Hoefer",NULL,"From biological processes to critical infrastructures and social phenomena, many complex systems may be studied as large networks of interacting components. Research investigating the important role of network topology is therefore of broad interest, where techniques may be developed, for example, to control complex dynamical processes with strategic network modifications. Applications range from mitigating damage incurred to critical infrastructure (e.g., the energy, banking, and transit systems) to controlling spreading processes, including both those that are harmful (e.g., epidemics) and beneficial (e.g., information dissemination). Among the many successful techniques for studying complex networks, spectral graph theory has been shown to be remarkably useful for analyzing and controlling the dynamical and robustness properties of a given network. In this thesis, I discuss my contributions to this field, which explore the following applications: (i) The analysis of a given networks robustness to the strategic removal of nodes and/or links (ii) The development of techniques to judiciously modify a network to tune its robustness and dynamical properties and (iii) The introduction and analysis of a network formation process yielding networks that self organize with enhanced spreading and robustness characteristics.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pgriua0arl2iu686hkr970blhs","2013-08-28 08:21:35","2013-08-29 08:08:02"
"1655","31","Stochastic modeling of soil water balance","2013-09-11 11:15:00","2013-09-11 12:15:00","SAS 4201","Xue Feng","http://porporato.cee.duke.edu/node/51","Duke University",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nc893dj1t49uj6fclieelpv21k","2013-08-28 08:31:19","2013-09-05 15:25:04"
"1657","3","Categorification in knot and graph theory. Part 1","2013-09-06 16:00:00","2013-09-06 17:00:00","SAS 4201","Radmila Sazdanovic","http://www4.ncsu.edu/~rsazdan/index.html","NC State",NULL,NULL,"Categorification can be thought of as a way of replacing an n category with an n+1 category, e.g,  lifting the Euler characteristic of a topological space to its homology. The main strength of categorification lies in realizing various classical objects as shadows of new, algebraically richer objects which often leads to beautiful and structurally deep mathematics.  Examples of categorification include Khovanov link and Heegaard Floer homology which lift the Jones and Alexander polynomials, respectively. There are also categorifications of the polynomial ring Z[x], the Heisenberg algebra, and quantum groups.We will focus on Khovanov homology for knots and links and related categorifications of the chromatic polynomial for graphs.  In particular, we will discuss torsion in Khovanov homology and describe the spectral sequence between  the chromatic graph homology defined by L. Helme-Guizon and Y. Rong and the homology of a graph configuration space introduced by M. Eastwood and S. Huggett.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/09barigohndj199bcpfgsrit68","2013-08-28 10:47:48","2013-09-02 13:58:02"
"1659","3","Categorification in knot and graph theory. Part 2","2013-09-09 14:30:00","2013-09-09 15:30:00","SAS 4201","Radmila Sazdanovic","http://www4.ncsu.edu/~rsazdan/index.html","NC State",NULL,NULL,"Categorification can be thought of as a way of replacing an n category with an n+1 category, e.g,  lifting the Euler characteristic of a topological space to its homology. The main strength of categorification lies in realizing various classical objects as shadows of new, algebraically richer objects which often leads to beautiful and structurally deep mathematics.  Examples of categorification include Khovanov link and Heegaard Floer homology which lift the Jones and Alexander polynomials, respectively. There are also categorifications of the polynomial ring Z[x], the Heisenberg algebra, and quantum groups.We will focus on Khovanov homology for knots and links and related categorifications of the chromatic polynomial for graphs.  In particular, we will discuss torsion in Khovanov homology and describe the spectral sequence between  the chromatic graph homology defined by L. Helme-Guizon and Y. Rong and the homology of a graph configuration space introduced by M. Eastwood and S. Huggett.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ieu2gu2efm8hq4gaa1q6t09ss0","2013-08-28 10:49:51","2013-09-02 13:57:44"
"1661","34","Work with Alex, Eric, and Liwen","2013-09-04 10:00:00","2013-09-04 11:15:00","SAS 4201","Jeff Thorne","http://statgen.ncsu.edu/thorne/","NCSU, Bioinformatics",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lfkorf59nire47e1ruoqmejruo","2013-08-28 13:51:59",NULL
"1663","4","Approximate Cloaking of Acoustic and Electromagnetic Waves","2013-09-11 15:00:00","2013-09-11 16:00:00","SAS 4201","Hongyu Liu","http://math2.uncc.edu/~hliu28/","Mathematics, UNC Charlotte","Mark Hoefer",NULL,"In this talk, I will describe the recent theoretical and computational progress on our work on regularized transformation-optics cloaking. Ideal cloak makes use of singular metamaterials, posing much challenge for practical realization. Regularization is incorporated into the construction in order to avoid the singular structures.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/s6sg5k4spnbrq2iseqcifb10j4","2013-08-28 15:57:40",NULL
"1667","34","Bayesian inference of species range evolution for hundreds of discrete areas","2013-10-02 10:00:00","2013-10-02 11:15:00","SAS 4201","Michael Landis",NULL,"UC Berkeley",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/iojud2k3h1v6184r6mescjcr14","2013-09-02 08:27:37","2013-09-27 12:57:40"
"1669","9","Combination of molecular and genetic data with mathematical modeling to understand how asymmetric cell division is regulated in the Arabidopsis root","2013-09-17 16:15:00","2013-09-17 17:15:00","Cox 306","Ross Sozzani","http://workthatmatters.ncsu.edu/newhires/sozzani.php","Plant and Microbial Biology Department, NC State","Alun Lloyd",NULL,"Stem cells are the building blocks for different cell types and tissues in all multicellular organisms. Overall growth rate and biomass are largely regulated by the temporal and spatial control of stem cell regeneration and differentiation of their progeny. Understanding how stem cells are maintained and organized should provide insight into how multicellular organisms initiate and maintain growth of their tissues and organs. There are several models for studying these processes in animals and plants, and the Arabidopsis root, due to the continuous post-embryonic nature of its development, and the presence of a confined stem cell niche, has emerged as a leading system among them. A key to system-level understanding of stem cell maintenance is the ability to analyze the dynamics of networks in the context of a living organism. The development of quantitative models to describe these dynamics, as well as parameter estimation to improve existing models, depends on the ability to obtain quantitative information about various proteins that are part of the regulatory network. The integration of imaging tools with genome-wide approaches and modeling of the stem cell regulatory networks provides the unique advantage of quantifying the function of biological circuits over time and at a cellular resolution. Understanding the mechanisms regulating stem cell maintenance within the root has the potential not only to identify novel plant-specific stemness factors, but also provide insights into common mechanisms underlying plant and animal stem cell programs.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d67ssuh3765hqn2ot32175srrc","2013-09-02 09:09:18",NULL
"1671","31","On the orbital stability of traveling wave solutions of the KdV equation","2013-11-13 11:15:00","2013-11-13 12:15:00","SAS 4201","Brian Pigott","http://users.wfu.edu/pigottbj/","Wake Forest University",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/v9543gurgm26r98bobiap091qo","2013-09-02 11:33:45","2013-10-21 10:47:15"
"1673","19","Journal Club","2013-09-04 15:00:00","2013-09-04 16:00:00","SAS 1220",NULL,"http://www4.ncsu.edu/~redavids/GraduateAlgebra.html",NULL,NULL,NULL,"Ruth will lead a discussion about the paper &quot;Lie Markov Models with purine/pyrimidine symmetry&quot;.  It can be found at http://arxiv.org/abs/1206.1401  .  This paper is a nice combination of Lie theory, phylogenetics, and representation theory of the symmetric group, but the paper should still be interesting to those without background in any of these subjects.  The discussion will be very informal.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/al9i10667oq43atjsncdam8lc8","2013-09-02 16:55:20",NULL
"1675","14","Departmental Tea and Cookies","2013-09-04 14:30:00","2013-09-04 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/nh0l7nf6ssboqiru8eq6dd16c8","2013-09-02 21:31:05",NULL
"1677","22","Whats a determinant, really?","2013-09-04 16:00:00","2013-09-04 16:50:00","SAS 2102","Nathan Reading",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/090413.pdf",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rh5r3jtr5a9aneiir4jcuermhk","2013-09-03 08:53:49","2013-09-03 10:05:27"
"1679","8","Synthesis of Optimal Numerical Algorithms by  Real Quantifier Elimination Case Study: Square Root Computation","2013-09-24 16:30:00","2013-09-24 17:30:00","SAS 4201","Madalina Erascu","http://www.risc.jku.at/home/merascu","RISCLinz","Hoon Hong",NULL,"Numerous problems in mathematics, science and engineering can be reduced to real quantifier elimination (quantifier elimination over real closed fields). Around 1930, Alfred Tarski showed that real quantifier elimination can be carried out algorithmically. In 1975, George Collins provided a dramatically more efficient algorithm. Since then, there has been intensive research to make further improvement of efficiency for a certain important class of formulas (inputs). In our research, we consider formulas arising in the synthesis of optimal numerical algorithms. In this talk, we present a case study on the square root problem: given the real number x and the error bound epsilon, find a real interval such that it contains sqrt(x) and its width is less than epsilon. As usual, we begin by fixing an algorithm schema, namely, iterative refining: the algorithm starts with an initial interval and repeatedly updates it by applying a refinement function, say R, on it until it becomes narrow enough. Then the synthesis amounts to finding a refinement function R that ensures that the algorithm is correct (loop invariant),  terminating (contraction), and optimal. All these can be formulated as quantifier elimination over the real numbers. Hence, in principle, they can be all carried out automatically. However the computational requirement is so huge, making the automatic synthesis practically impossible with the current general quantifier elimination software.  Hence, we did some hand derivations and were able to synthesize semi-automatically optimal algorithms under suitable assumptions. We hope that the ideas behind the hand derivations could be eventually turned into an algorithm.  This is joint work with Hoon Hong.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tq9jpnp8n3mq8pvpigqbdq616o","2013-09-03 14:02:14","2013-09-23 08:11:26"
"1681","23","Preparing your CV, Teaching and Research Statements","2013-09-13 15:00:00","2013-09-13 16:00:00","SAS 4201","Math Department Faculty",NULL,"NC State",NULL,NULL,"This seminar will focus on strategies for preparing application materials targeted at academic jobs.  The three primary application components to be discussed are the curriculum vitae (CV), research statement and statement of teaching philosophy.  A brief presentation of helpful resources will be followed by a panel discussion with departmental faculty members.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3s9uo1irv044g4c1qf41a2lgr0","2013-09-04 11:01:18","2013-09-04 11:09:12"
"1683","34","Distributions on Distance Matrices","2013-09-11 10:00:00","2013-09-11 11:15:00","SAS 4201","Ruth Davidson","http://www4.ncsu.edu/~redavids/","NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6p6iog6p8klgr9v705n16nqj1s","2013-09-05 09:42:07",NULL
"1685","8","High-dimensional random landscapes and random matrices","2013-10-01 16:30:00","2013-10-01 17:30:00","SAS 4201","Yan Fyodorov","http://www.maths.qmul.ac.uk/~yan/","Queen Mary University","Dhagash Mehta",NULL,"Most of optimization problems can be formulated as search of the global minimum of a cost functionwhich is convenient to think of as a landscape in configuration space. When landscapes are high-dimensional and random the search is difficult and one would like to understand generic features of such landscapes.Simple, yet rich and non-trivial models of random landscapes are provided by mean-field spin glasses and related systems.  I am going to present a picture of the &quot;topology trivialization transition&quot; (in the sense of an abrupt  reduction of the number of stationary points and minima of the underlying energy landscape) which takes place in the vicinity of the zero-temperature glass transition of p-spin spherical model of spin glasses. In particular, I will emphasize the role of the &quot;edge scaling&quot; and the Tracy-Widom distribution of the largest eigenvalues of random matrices for providing some universal features of the above transition.  Part of the results to be presented in the talk were obtained in recent joint works with Pierre Le Doussal and with Celine Nadal.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q6iajqsukjv6l5dio2h51vhkqo","2013-09-05 13:03:22","2013-09-05 13:05:30"
"1687","8","Applications of Symbolic and Numerical Algebraic Geometry Methods in Theoretical Physics and Chemistry","2013-09-10 16:30:00","2013-09-10 17:30:00","SAS 4201","Dhagash Mehta","http://www.math.ncsu.edu/~dbmehta","NC State","Jon Hauenstein",NULL,"Many problems in theoretical physics and theoretical chemistry boil down to solving polynomial equations, either univariate or multivariate polynomials. The task may be to (1) find all the isolated solutions, (2) compute the primary or irreducible decomposition, (3) find all the local and global minima, (4) find the global minimum, (5) compute the Hilbert series, elimination, parametrizing the variety, etc. In short, the problems become the best place to usefully apply symbolic and numerical algebraic geometry methods to extract the corresponding science out of it. In this talk, I will explain some of the problems I have been working on recently. I will then also list the problems in which the methods developed by our Symbolic Computation group may be useful.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/luuf6sn0o478r72dhnq94m3nqk","2013-09-05 14:25:17","2013-09-09 13:00:36"
"1689","19","Introduction to Cluster Algebras","2013-09-11 15:00:00","2013-09-11 16:00:00","SAS 1220","Salvatore Stella","http://www4.ncsu.edu/~sstella/index.html","NCSU",NULL,NULL,"Background reading for interested parties can be found in &quot;Cluster Algebras I&quot; by Fomin and Zelevinsky, available full text access at the following link:http://www.ams.org/journals/jams/2002-15-02/S0894-0347-01-00385-X/","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p9f0ng55495sih0pbjqp7iubcg","2013-09-06 10:14:37","2013-09-06 10:40:41"
"1691","19","Intro to Liebnitz Algebras and the Frattini Subalgebra","2013-09-18 15:00:00","2013-09-18 16:00:00","SAS 1220","Allison McAlister Hedges",NULL,"NCSU",NULL,NULL,NULL,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6mge1us6n7sajgq3nc80qtk92g","2013-09-06 10:19:26",NULL
"1693","19","TBA","2013-09-25 15:00:00","2013-09-25 16:00:00","SAS 1220","Emily Barnard",NULL,"NCSU",NULL,NULL,NULL,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cipquhvt9660k4uu7l3uopit94","2013-09-06 10:20:40",NULL
"1697","19","Distance-based phylogenetic methods near a polytomy","2013-10-02 15:00:00","2013-10-02 16:00:00","SAS 1220","Ruth Davidson","http://www4.ncsu.edu/~redavids/","NCSU",NULL,NULL,"A phylogenetic tree models the common evolutionary history of a group of species.  A tree metric is a distance function on a set of species realized by a tree with edge weights.  Distance-based phylogenetic algorithms attempt to solve the NP-hard least-squares phylogeny problem by mapping an arbitrary dissimilarity map representing biological data to a tree metric.  The set of all dissimilarity maps is a Euclidean space properly containing the space of all tree metrics as a polyhedral fan.  Outputs of distance-based tree reconstruction algorithms such as UPGMA and Neighbor-Joining are points in the maximal cones in the fan.   Tree metrics with polytomies, or internal vertices of degree higher than three, lie at the intersections of maximal cones.  A phylogenetic algorithm divides the space of all dissimilarity maps into regions based upon which combinatorial tree is reconstructed by the algorithm.  We use polyhedral geometry to compare the local nature of the subdivisions induced by least-squares phylogeny, UPGMA, and Neighbor-Joining.  Our results suggest that in some circumstances, UPGMA and Neighbor-Joining poorly match least-squares phylogeny when the true tree has a polytomy.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r51gpllk49p02n8ls0kj7orof0","2013-09-06 10:23:37","2013-09-23 16:27:43"
"1699","19","Polyhedral models for generalized associahedra via Coxeter elements","2013-10-16 15:00:00","2013-10-16 16:00:00","SAS 1220","Salvatore Stella","http://www4.ncsu.edu/~sstella/index.html","NCSU",NULL,NULL,"Motivated by the theory of cluster algebras, S. Fomin and A. Zelevinsky have associated to each finite type root system a simple convex polytope called generalized associahedron. It turns out that this purely combinatorial gadget encodes many informations on the associated cluster algebra making it an interesting object to study. I will describe, after recalling the basic definitions, a family of geometric realizations of these polytopes, parametrized by orientations of the corresponding Dynkin diagram. I will also show that this construction agrees with the one given by C. Hohlweg, C. Lange and H. Thomas in the setup of Cambrian fans developed by N. Reading and D. Speyer.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gj4105i2jr2mo12k4s4t4b1lj0","2013-09-06 10:25:14","2013-10-15 15:19:05"
"1701","19","Langlands Correspondence","2013-10-23 15:00:00","2013-10-23 16:00:00","SAS 1220","Mark Hunnell","http://www4.ncsu.edu/~mchunne2/","NCSU",NULL,NULL,NULL,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/087ffu9dbck47ftr0iatig1ta4","2013-09-06 10:26:51",NULL
"1703","19","Leibniz Algebras","2013-11-20 15:00:00","2013-11-20 16:00:00","SAS 1220","Alison McAlister Hedges",NULL,"NCSU",NULL,NULL,"Leibniz algebras, a generalization of Lie algebras, were first investigated in 1993 by Jean-Louis Loday. These structures arose from studying the homology of Lie algebras. It is natural to consider Lie algebra results and to discover which of these results can be successfully generalized to Leibniz algebras. Many of these results have analogues in the Leibniz algebra case, such as Lies theorem, Engels theorem, and a number of results concerning the Frattini subalgebra and ideal. However there are a number of results which do not generalize to the Leibniz case. In an attempt to easily construct examples of a Leibniz algebra which is not Lie, we can construct a cyclic Leibniz algebra of order three or more. These algebras often yield illuminating examples of these concepts, and as such, we study these in some detail.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ju7bcri3l2i6dsk51dt7cvo5ts","2013-09-06 10:28:13","2013-11-19 15:57:51"
"1705","19","Cadenza: an algorithm for a posteriori certified path tracking","2013-12-04 15:00:00","2013-12-04 16:00:00","SAS 1220","Alan Liddell",NULL,"NCSU",NULL,NULL,"The problem of path tracking presents itself in a number of applications, including the solving of polynomial systems. We develop an algorithm for rigorously certifying the continuity of a numerically approximated solution path of a so-called Newton homotopy.  The algorithm is based on Smales alpha theory used for certifying the quadratic convergence of Newtons method.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/195924h48icbg9hmt6dt4eeg4s","2013-09-06 10:31:25","2013-12-03 13:19:08"
"1709","6","On semilagrangian methods for kinetic equations.","2013-10-29 15:00:00","2013-10-29 15:50:00","SAS 4201","Giovanni Russo","http://www.dmi.unict.it/~russo/","University of Catania","Alina Chertok",NULL,"The purpose of this talk is to present some recent results on the development of semilagrangian high order method for some kinetic equations. Two particular applications are considered, namely Vlasov-Poisson system and BGK model. For the VP system, high order semilagrangian methods are obtained by tracing back the characteristics form each grid node in phase space, by solving (backward) their evolution equation in a self-consistent electric field. The solution at the foot of the characteristic at time $t_n$ is reconstructed by WENO interpolation in space and velocity.For the BGK model, high order semilagrangian schemes are obtained by integrating the equation along the characteristics (in the forward direction). Since there is no drift, the characteristics are known, and the solution at time $t_n$ at the foot of the characteristic is obtained by WENO interpolation in space. Implicit schemes are used to avoid restriction on the time step in case of small relaxation time. Because of the special structure of the collision operator of BGK, the implicit equation can be explicitly solved. Two family of schemes are considered and compared: implicit Runge-Kutta and BDF.Both approaches described above (for VP and BGK) are non conservative in nature. The third part of the talk is devoted to a general technique that can be used to make the method conservative. The approach is a conservative correction that can be applied to a non conservative method. Examples of conservative schemes constructed by this techniques are illustrated in various contexts. When applied to semilagrangian schemes, the technique suffers from CFL-type stability restriction. Stability analysis is performed to understand the instability due to time discretization, however the contribution of space discretization has not yet been analyzed.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2riu530m8anpkdg0psebcq4bqg","2013-09-06 10:48:26","2013-09-06 15:40:59"
"1711","26","Variability in CFSE-Based Flow Cytometry Data","2013-09-09 16:00:00",NULL,"SAS 4201 ","Dustin Kapraun","http://www4.ncsu.edu/~dfkaprau/cell_prolif/cell_prolif.html",NULL,NULL,NULL,"In this talk, we discuss variability in cell proliferation dynamics observed for CD4+ and CD8+ T cells collected from two healthy donors. We review a recently developed class of models that incorporates the so-called &quot;cyton model&quot; for cell numbers into a conservation-based PDE model for cell population dynamics. (This class of models was presented to AMGSS in more detail in April 2013, and slides from that talk are available at the link below.) By applying a parameter estimation scheme to a large body of data, we are able to assess experimental variability (variation in parameter estimates as identical experiments are replicated) and biological variability (differences in parameter estimates obtained for different donors and cell types). Variability in the data obtained from replicated experiments is also discussed.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4c5fl1llc989qk4o3hbogei2o0","2013-09-09 08:13:19",NULL
"1713","14","Departmental Tea and Cookies","2013-09-11 14:30:00","2013-09-11 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ps9l1odbgdbed3s8rv121o1ut8","2013-09-09 09:57:23",NULL
"1715","22","Dont cross the arcs!","2013-09-11 16:00:00","2013-09-11 16:50:00","SAS 2102","Nathan Reading",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/091113.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t5k8mb1j1mslbmivrh4bpmingo","2013-09-09 10:11:49",NULL
"1717","4","Numerical stability analysis for thin film flow: toward rigorous verification","2013-09-30 15:00:00","2013-09-30 16:00:00","SAS 2102","Blake Barker","http://www.math.indiana.edu/people/profile.phtml?id=bhbarker","Mathematics, Indiana University","Stephen Schecter",NULL,"We discuss various aspects of numerical stability analysis of periodic roll wave solutions arising in equations of inclined thin film flow, with a particular eye toward the development of guaranteed error bounds. In particular, we consider stability of periodic waves of the generalized Kuramoto-Sivashinsky (KS) equation in the Korteweg-de Vries (KdV) limit. The KS equation can be derived from the Navier-Stokes equations or the St. Venant equations precisely in the parameter regime corresponding to pattern formation. The KS equation can be viewed as a dissipative singular perturbation of the KdV equation. Periodic KdV traveling waves are known to be spectrally stable to small localized perturbations, but are &quot;neutrally&quot; stable, so that periodic traveling waves of KS in this limit may be either stable or unstable. It is this question of stability that we seek to answer via rigorous numerical verification.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3rbmgm9lo5r63u58c8en6rpl9g","2013-09-09 11:37:17","2013-09-17 15:59:56"
"1721","14","Departmental Tea and Cookies","2013-09-20 15:30:00","2013-09-20 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/emt530g3fql25qi6ub5uc3tgo4","2013-09-10 11:11:30",NULL
"1723","21","2013 Todd Fuller Contest","2013-10-19 08:00:00","2013-10-19 10:00:00","SAS 2203",NULL,NULL,NULL,NULL,"http://www.math.ncsu.edu/undergrad/ncsu_contests/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9t0a1ljmvg30ae73gf1j5vrf2o","2013-09-10 11:36:42",NULL
"1725","26","Observer-based fault detection and identification in systems modeled by differential-algebraic equations","2013-09-16 16:00:00",NULL,"SAS 4201 ","Jason Scott",NULL,NULL,NULL,NULL,"Fault detection and identification (FDI) are important tasks in most modern industrial and mechanical systems and processes. Many of these systems are most naturally modeled by differential algebraic equations. One approach to FDI is based on the use of observers and filters to detect and identify faults.  The method presented here uses the least squares completion to compute an ODE that contains the solution of the DAE and applies the observer directly to this ODE. Robustness with respect to disturbances is also addressed by a frequency filtering technique.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fh3bpghglf3ac0rp9ur06avl5c","2013-09-10 12:53:14",NULL
"1727","15","Lunch and Organizational Meeting","2013-09-19 12:30:00","2013-09-19 13:15:00","Poe 228",NULL,NULL,NULL,NULL,NULL,"The SIAM Student Chapter at NCSU will be hosting its first meeting of the year on Thursday, September 19, at noon in Poe 228. Come to this short meeting to enjoy a free lunch with fellow students and find out:1. How to get a free student membership to SIAM, as well as the benefits of being a SIAM member. These benefits include, among other things, travel money opportunities.2. Information about our upcoming speakers for the semester.Anyone is welcome to attend!","mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/llkuqhg2jbqmo4o1f6u48hit3k","2013-09-12 11:41:41","2013-09-13 08:36:43"
"1731","8","An OM Algorithm","2013-11-05 16:30:00","2013-11-05 17:30:00","SAS 4201","Sebastian Pauli","http://www.uncg.edu/mat/faculty/pauli/","UNC Greensboro","Erich Kaltofen",NULL,"An OM algorithm, where OM stands for Ore-Montes or Okutsu-MacLane is an algorithm that computes the Okutsu invariants of a polynomial over a local field.  The Okutsu invariants include the ramification index and inertia degree of the irreducible factors of the polynomial.  The data returned by the OM algorithm can be used to obtain its factorization of, to find local and global integral bases, and the decomposition of ideals in global fields.  We give an OM algorithm and related results and applications.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c59dvubvivctb77v7357u3v6c8","2013-09-17 09:56:06","2013-11-01 16:33:40"
"1733","22","Predicting the next pitch","2013-09-18 16:00:00","2013-09-18 16:50:00","SAS 2102","Joe Murray",NULL,"NC State",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/091813.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tqbti8hp8lvprrhd9jppdt256o","2013-09-17 10:24:06",NULL
"1735","22","Magic, Mathemagic, and Mathematics","2013-11-13 16:00:00","2013-11-13 16:50:00","SAS 2102","David Taylor","http://webapps.roanoke.edu/faculty/display.cfm?username=taylor","Roanoke College",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/111313.pdf","Magic and mathematics have been paired together for centuries&quot;tricks&quot; involving starting with a number, performing variousarithmetic calculations, and then ending with the starting number(or associated number) have seen plenty of use.  While it can bequite simple to discover their secrets (use a variable x for thestarting number and see what the arithmetic sequence produces),mathematics can produce more eye-catching and &quot;current&quot; magictricks.  In this talk, we will focus on the various types ofmathematical results, theories, and &quot;trickery&quot; that lie behindsome good magic tricks, mostly involving cards.  For briefintermissions, between mathematics explanations, some card trickswill be performed, using randomly determined audience members,involving cards, without explanation.  It will be a fun time forall, so come enjoy and relax!","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r6vleb2anohbf4p8lau3t1kl3g","2013-09-17 13:06:29","2013-11-12 12:47:34"
"1737","22","Google PageRanking NFL Teams","2013-10-16 16:00:00","2013-10-16 16:50:00","SAS 2102","Laurie Zack","http://linus.highpoint.edu/facultywebpages/lzack/","High Point University",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/101613.pdf",NULL,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3umlgt1hv07d3a2qjfmacmv1vg","2013-09-17 13:36:48","2013-10-15 11:04:52"
"1739","22","The Curvatures of a Surface","2013-10-23 16:00:00","2013-10-23 16:50:00","SAS 2102","Andrew Cooper","http://www4.ncsu.edu/~aacoope2/","NC State",NULL,NULL,"What does it mean to be curved? If we can see enough of an object (suchas the surface of a sphere or a doughnut), it is easy to tell visuallywhether it is curved or not. But if we can only see a small piece of thesurface (and we dont happen to have Columbus handy), the answer ismuch less obvious.In this talk, well explore the mean curvature and Gauss curvature of asurface. These measures have the admirable quality that they can becomputed using only locally-available information. Well see whatcurvature have to do with problems like finding the diameter of theearth, drawing pictures on a balloon, and giftwrapping an innertube.Well also briefly mention how to make sense of the idea of curvedthree-dimensional space.Only a bit of calculus is required, but a little bit of linear algebrawill go a long way, too. You should also be willing to roll, fold, andtear paper.","spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6j2cbkkdahok9pvs6dpria6bd4","2013-09-17 13:38:34","2013-10-16 11:41:31"
"1741","22","Sports Ranking and Prediction","2013-10-30 16:00:00","2013-10-30 16:50:00","SAS 2102","Anjela Govan","http://stmacademy.org/about/faculty-staff/2035-2/","Saint Thomas Moore Academy",NULL,NULL,"The rank of an object is its relative importance to the other objects in the set. Often a rank is an integer assigned from the set 1,2,...,n. A ranking model is a method of determining a way in which the ranks are assigned. Usually a ranking model uses information available on the objects to determine their respective ratings.The most recognized application of ranking is the competitive sports. Numerous ranking models have been created over the years to compute the team ratings for various sports. In this talk we discuss a flexible, easily coded, fast, iterative approach, we call the Offense-Defense Model (ODM), to generating team ratings. The convergence of the ODM is grounded in the theory of matrix balancing and the Sinkhorn-Knopp theorem (1967) provides us with the requirements for the convergence. As a way of testing, the ODM has been used to do game predictions. Some of the prediction results, using popular sports, are included in this presentation.","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hltpmc1g2pdtbcu85gvlmojet0","2013-09-17 13:40:30","2013-10-01 09:59:42"
"1743","22","Binomial Trees and Black Scholes","2013-11-06 16:00:00","2013-11-06 16:50:00","SAS 2102","Jeff Scroggs","http://www4.ncsu.edu/~scroggs/mywebsite/","NC State",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/110613.pdf",NULL,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8j93ii1qmqbq5qec0bd89jjgcs","2013-09-17 13:41:25","2013-11-04 11:58:50"
"1747","22","Mathematical Modeling of Cartilage Tissue Engineering","2013-11-20 16:00:00","2013-11-20 16:50:00","SAS 2102","Mansoor Haider","http://www4.ncsu.edu/~mahaider/","NC State",NULL,"http://www.math.ncsu.edu/sumseries/fall2013/112013.pdf",NULL,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/70jbp1893k22p0gi86lam8trm4","2013-09-17 13:46:41","2013-11-13 11:31:27"
"1749","22","Undergraduate Research Presentations","2013-12-04 16:00:00","2013-12-04 16:50:00","SAS 2102","Mathematics Undergraduate Research Presentations",NULL,"NC State",NULL,NULL,"1.   Marschall Furman Title :  The Regulatory Effect of MicroRNAs on the DNA Mismatch Repair PathwayAbstract : Although failure of DNA Mismatch Repair (MMR) is associated with microsatellite instability and colorectal cancer, little is known about MMR except for its biochemical pathway. Our project introduces the first gene regulatory network of MMR by assembling known regulatory interactions. We designed novel update functions for use in the Stochastic Discrete Dynamical Systems (SDDS) framework. Our model provides us with phenotypic predictions for MMRs response to hypoxia and UV radiation. Using techniques from chaos theory, we also test the hypothesis that microRNAs in feedforward loops stabilize network dynamics and thus increase genomic stability. So in addition to providing a gene regulatory network of MMR, our model allows us to assess the viability of SDDS in modeling biological systems by providing experimentally verifiable predictions and to analyze the potential stabilizing effect of microRNAs on dynamics of biological networks.  -------------------------------------------------------------------------------------2.  Laura Poag,  Robert Baraldi and Emma Thorpe Title :  Uncertainty Quantification in Modeling HIV Viral Mechanics Abstract :  We consider an in-host model for HIV-1 infection dynamics developed and validated with patient data in earlier work [3]. We revisit the earlier model in light of progress over the last several years in understanding of HIV-1 progression in humans. We then consider statistical models to describe the data and use these with residual plots in generalized least squares problems to develop accurate descriptions of the proper weights for the data. Bootstrapping and asymptotic theory are compared in the context of confidence intervals for the resulting parameter estimates. We also consider questions related to correlation in the estimated parameters. Finally we use recent parameter subset techniques [2] to investigate the impact of estimated parameters on the corresponding selection scores. -------------------------------------------------------------------------------------3.  Alex Chin Title :  Graph Subtree PolynomialsAbstract :  A graph is a mathematical structure that allows us to study the interconnectedness of a set of objects.  Given a graph, how can we study the behavior of the subtrees of that graph?  We explore the prevalence of subtrees of various sizes in the complete graph and define a generating function polynomial that can help answer some open questions.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/44b1407gn1k6s760k1b6hug2k4","2013-09-17 13:47:54","2013-12-02 10:03:09"
"1751","26","Bayesian Parameter Estimation In The Presence Of Model Discrepancy","2013-09-23 16:00:00",NULL,"SAS 4201","Jerry McMahan",NULL,NULL,NULL,NULL,"Bayesian inference techniques for parameter estimation of uncertain dynamical systems typically rely on certain assumptions about the statistical properties of the modeling error. In cases where these assumptions are violated due to deterministic but unknown discrepancies in the model, these techniques become inaccurate. In this talk, I will discuss some of my ongoing research with Ralph Smith to attempt to address this issue.","mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9icb05uv1biujpo8sh149ktiig","2013-09-20 12:15:05",NULL
"1753","34","Models for Accumulating Mutations","2013-09-25 10:00:00","2013-09-25 11:15:00","SAS 4201","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0738uqn2euugqa29cl8roc6j4c","2013-09-22 11:30:14",NULL
"1755","14","Departmental Tea and Cookies","2013-09-25 14:30:00","2013-09-25 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/paofcd5n60njpo6pmh8cs5htf0","2013-09-23 10:11:37",NULL
"1757","34","Introduction to Applied Topology","2013-11-13 10:00:00","2013-11-13 11:15:00","SAS 4201","Radmila Sazdanovic","http://www4.ncsu.edu/~rsazdan/","NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/q1fl91a9v2j6pnsct1q5ijm7vo","2013-09-25 09:52:17",NULL
"1759","3","Weyl character formulas, vertex operators and Littlewood duality","2013-10-07 14:30:00","2013-10-07 15:30:00","SAS 4201","Naihuan Jing","http://www4.ncsu.edu/~jing/","NC State",NULL,NULL,"Weyl gave an effective algorithm to compute the characters of irreducible modules of classical Lie algebras using tensor powers of the fundamental representations. Weyls theory can be formulated in the Schur symmetric functions and their orthogonal/symplectic analogs. In this talk, I will first review the vertex operator approach to classical symmetric functions such as Schur functions, and discuss recent work on vertex operator approach to Weyls character formulas. This approach can help us obtain several new determinant formulas for Weyl characters as well as giving a new proof and interpretation of the Littlewood duality between the characters of the orthogonal and symplectic groups.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j4ka1mqohs9medotnfnf7r5f9o","2013-09-26 10:12:02","2013-10-01 20:43:59"
"1761","1","Growth, patterning, and control in nonequilibrium systems","2013-10-24 16:00:00","2013-10-24 17:00:00","SAS 1102","John Lowengrub","http://www.math.uci.edu/~lowengrb","University of California, Irvine","Sharon Lubkin",NULL,"A variety of pattern-forming phenomena, ranging from the growth of bacterial colonies to snowflake formation, share similar underlying physical mechanisms and mathematical structure. Dense-branching or dendritic morphologies are among the most common forms of microstructural patterning in systems driven out of equilibrium. Understanding the formation kinetics and the interplay of system parameters can lead to understanding of growth and form in nature, as well as improved control and efficiency in a variety of physical, biological, and engineering systems. Prediction and control of the emergent patterns are difficult due to the nonlocality and nonlinearity of the system. In this talk, we focus on viscous fingering as a paradigm for such phenomena. In particular, we study theoretically, numerically, and experimentally the dynamics and control of viscous fingering patterns in a circular Hele-Shaw cell.  By controlling the injection rate of the less viscous fluid, we can precisely suppress the evolving interfacial instabilities. There exist denumerable attractive, self-similarly evolving, symmetric universal shapes. Experiments confirm the feasibility of the control strategy, which is summarized in a morphology diagram. Extensions of the results to other pattern-forming systems will be discussed.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/83np3paf0nuf2l69diek3ujthc","2013-09-26 11:00:37","2013-10-18 10:56:04"
"1763","3","Classification of orbifold modules using twisted modules","2013-10-28 14:30:00","2013-10-28 15:30:00","SAS 4201","Jason Elsinger","http://www4.ncsu.edu/~jrelsing/","NC State Mathematics Graduate Student",NULL,NULL,"Given an integral lattice L, one can construct a corresponding vertex algebra V using the Heisenberg algebra and the group algebra of L. Let T be an automorphism of V . The set of T-invariant elements is called an orbifold. C. Dong and others have used Zhus algebra to classify all orbifold modules in the case T = -1. On the other hand, B. Bakalov and V. Kac have a way of constructing all possible twisted modules for any automorphism. In the case for an even positive definite integral lattice Q and an automorphism T of order 2, I use their construction to find all T-twisted modules and verify that there are no others using the works of C. Dong and others. These include, in particular, the root lattices for the simply-laced Lie algebras with a Dynkin diagram automorphism of order 2.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/84a47bgl9v826c3hki8o47dqic","2013-09-26 11:35:56","2013-10-23 11:48:06"
"1765","6","TBA","2013-09-21 16:00:00","2013-09-21 16:50:00","SAS 4201","Jill Reese",NULL,"The Mathworks","Tim Kelley",NULL,"TBA","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3epm7p4rbi2410gkv8mafuk8hc","2013-09-28 14:15:24",NULL
"1771","26","Computational Model for Optical Coherence Tomography Imaging of the Human Eye","2013-09-30 16:00:00",NULL,"SAS 4201","Micaela Mendlow",NULL,NULL,NULL,NULL,NULL,"mtonoe","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lher2n2kuepc5tbfanqv624f5g","2013-09-28 19:56:26",NULL
"1775","14","Departmental Tea and Cookies","2013-10-02 14:30:00","2013-10-02 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hieu6hjhhp9nies08ib8eiljps","2013-09-30 09:43:41",NULL
"1777","21","Scientific Computing Opportunities at Sandia National Labs","2013-10-01 17:00:00","2013-10-01 18:00:00","SAS 1102","Brian Adams",NULL,"Sandia National Labs","Mansoor Haider",NULL,NULL,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3efrkqugn5gsdqreibuqf0rqg4","2013-09-30 10:48:28","2013-09-30 10:49:13"
"1779","3","Wonder of sine-Gordon Y-systems","2013-10-21 14:30:00","2013-10-21 15:30:00","SAS 4201","Salvatore Stella","http://www4.ncsu.edu/~sstella/","NC State",NULL,NULL,"The sine-Gordon Y-systems and the reduced sine-Gordon Y-systems were introduced by Tateo in the 90s in the study of the integrable deformation of conformal field theory by the thermodynamic Bethe ansatz method. The periodicity property and the dilogarithm identities concerning these Y-systems were conjectured by Tateo, and recently proved using cluster algebras. In this talk we explain how these Y-systems can be understood using triangulations of polygons and how this provides automatically a proof of both periodicity and dilogarithm identities in full generality.","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qhi7lgqq747mrc5ceabucgja0c","2013-10-03 14:52:16","2013-10-18 13:14:21"
"1781","4","Biological aggregation in nonlocal models","2013-10-30 15:00:00","2013-10-30 16:00:00","SAS 4201","Ciprian Gal","http://www2.fiu.edu/~cgal/","Florida International University","Lorena Bociu",NULL,"We wish to discuss recent developments concerning the long term behavior in terms of (possibly finite-dimensional) global attractors and convergence to a single equilibrium, as time goes to infinity, of solutions to a continuum model for biological aggregations. The model is the aggregation equation with both degenerate and non-degenerate diffusion in which individuals experience long-range social attraction and short range dispersal.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a2b7lkn89onrut29pdfcl5sm78","2013-10-07 16:27:58",NULL
"1783","34",NULL,"2013-10-16 10:00:00","2013-10-16 11:15:00","SAS 4201","Eric Stone","http://www4.ncsu.edu/~eastone2/","NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9ogia84q4c9mc472gb09iii2u0","2013-10-08 15:56:58",NULL
"1785","4","Fluid ratcheting by oscillating channel walls with sawteeth","2013-11-06 15:00:00","2013-11-06 16:00:00","SAS 4201","Jie Yu","http://www4.ncsu.edu/~jyu4/","Civil Engineering, NC State",NULL,NULL,"Motions rectified by symmetry-breaking mechanisms in oscillating flows have beenof great interest in biological locomotion and engineering applications.  Recently, an experiment demonstrated that in a narrow channel between two parallelplates, with their facing sides lined with asymmetrical sawteeth andharmonically oscillating oppositely and normally, fluid can be pumped from one endto the other.  Since the directional transport is achieved without valves, this demonstration of fluid ratcheting using geometric asymmetry also offers an alternative idea for valveless pumps, which remain active interests in microfluidics and biomedical engineering appliciations. Inspired by the experiment, we put forward here a theory describing the ratcheting effect of a fluid. In a conformally transformed plane,the analytical solution is given, invoking a boundary layer approach.  The rectification of time harmonic motions is due to the nonlinear inertia and interaction of fluid with the wall motion. The geometric asymmetry renders these effects to be spatially biased, leading to a unidirectional component in the rectified flow. Whereas the wall sawtooth shape is a source of asymmetry, the difference in entrance and exit flow conditions due to the geometries at the channel ends is found to be a second source to break the left-right symmetry of the system.  Various influences on the net pumping rate are analysed.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7fn0tafem1m5bedt6km3ekfljo","2013-10-09 11:19:25","2013-10-10 15:23:48"
"1787","26","Decomposition Of Permittivity Contributions From Reflectance Using Mechanism Models","2013-10-14 16:00:00","2013-10-14 17:00:00","SAS 4201","Jared Catenacci",NULL,NULL,NULL,NULL,"In this talk, we investigate the properties of a complex nonmagnetic material using reflectance data.  We consider the case where the permittivity of the material is described by a mechanism model in which an unknown probability measure is placed on the model parameters.  Specifically, we consider whether or not this unknown probability measure can be determined from the reflectance or both the reflectance and the derivative of the reflectance.  Care will be taken to provide an outline of the theoretical justification for estimating distributions of parameters using the Prohorov metric framework.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jbffo4t0b0ufm4l3kcchftrrv4","2013-10-11 08:13:49",NULL
"1789","14","Departmental Tea and Cookies","2013-10-17 15:30:00","2013-10-17 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/u3a35n4p4okdrsh7l08rd7p8k8","2013-10-14 09:35:55",NULL
"1791","9","Mathematical modeling of cardiovascular dynamics during head-up tilt","2013-10-22 16:15:00","2013-10-22 17:15:00","Cox 306","Nakeya Williams",NULL,"NC State Applied Mathematics Graduate Student",NULL,"http://www.ncsu.edu/biomath/abstracts/AbstractNakeya.pdf",NULL,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/aihc2bk338474m5so2vdej1s80","2013-10-16 09:44:46",NULL
"1793","9","Bacillus and Clostridia in acidified foods: dangerous metabiotic effects?","2013-11-12 16:15:00","2013-11-12 17:15:00","Cox 306","Fred Breidt",NULL,"USDAARS",NULL,"http://www.ncsu.edu/biomath/abstracts/AbstractFredBreidt.pdf",NULL,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/dclni1ikjiquapbnkulrf1oklc","2013-10-16 09:45:52",NULL
"1795","9","Parallelizing forward-time population genetics simulations on GPUs: How ecology makes it worth the trouble","2013-11-19 16:15:00","2013-11-19 17:15:00","Cox 306","Kenichi Okamoto",NULL,"NC State Entomology Department",NULL,NULL,"As our understanding of the genetic basis of complex traits improves, elucidating the dynamics of alleles affecting ecologically important quantitative traits in natural communities becomes key to integrating theory and data in evolutionary ecology. Linking classical population genetics and community ecology theory, however, remains challenging. Individual-based models (IBMs) provide one approach to model the interplay between evolutionary and ecological dynamics. Yet in practice, analyzing these models can be computationally daunting. As stochastic simulations, IBMs often require several replicates per parameter combination and that several such combinations be analyzed. Modern central processing units are unlikely to see substantive performance improvements, requiring that IBMs be parallelized. Often running such parallel applications requires considerable financial investment and institutional support. Here I propose a multi-species, forward-time population genetics simulator and framework exploiting relatively economical graphics processing units (GPUs). I show how, depending on the ecology modeled, simulations paralellized for a GPU can run up to 70 times faster than single-core implementations. I apply this approach to two very different case studies: the evolution of clutch size in size-structured predator-prey communities, and antagonistic coevolution in space.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5cp27956kker9l2l9ln64ut4u4","2013-10-16 09:46:49","2013-11-08 13:15:24"
"1797","9","Mathematical and computational mixture models for cartilage regeneration in cell-seeded scaffolds","2013-12-03 16:15:00","2013-12-03 17:15:00","Cox 306","Mansoor Haider",NULL,"NC State Mathematics Department",NULL,NULL,"Mathematical and computational mixture models for cartilage regeneration in cell-seeded scaffoldsCartilage physiology is regulated by a single population of specialized cells called chondrocytes.  The chondroyctes are sparsely distributed within a porous and permeable extracellular matrix and maintain a state of homeostasis in healthy tissue. Extracellular matrix degeneration due to osteoarthritis can lead to compete degradation of cartilage surfaces, necessitating total joint replacement.   Chondrocytes can be utilized to regenerate cartilage via tissue engineering approaches in which these cells are seeded in biocompatible and degradable porous biopolymer or hydrogel scaffold materials. In such systems, biosynthetic activity of the cells in response to their non-native environment results in regeneration and accumulation of extracellular matrix constituents concurrent with degradation of the surrounding scaffold material.  Continuum mixture models are presented for interactions between biosynthesis of extracellular matrix constituents and matrix linking in biomaterial scaffolds seeded with chondrocytes.  These models are focused on describing effects of evolving porosity on functional outcomes in the tissue-engineered constructs. Both ODE-based (temporal) models for evolution of average apparent densities and PDE-based (spatio-temporal) models will be presented for variables including unlinked extracellular matrix, linked extracellular matrix and scaffold.  Recent work on multiscale, single cell based modeling techniques, will also be discussed.   These models provide a quantitative framework for assessing and optimizing the design of engineered cell-scaffold systems and guiding strategies for articular cartilage tissue engineering.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h2bsu0vugdo1ni434ipn6nvpjg","2013-10-16 09:47:49","2013-11-29 11:28:52"
"1799","6","Parallel Computing with MATLAB","2013-10-21 16:00:00","2013-10-21 16:50:00","SAS 4201","Jill Reese",NULL,"Mathworks","Tim Kelley",NULL,"The MATLAB Parallel Computing Toolbox (PCT) and the MATLAB DistributedComputing Server (MDCS) allow MATLAB users to leverage the computepower of multi-core/multi-processor computers, graphics processingunits (GPUs), and clusters.  This talk provides an introduction to thefeatures of PCT and MDCS as of release R2013b.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2ma92g9bdbhpbq49no8m9nrepo","2013-10-16 10:28:20","2013-10-16 13:48:06"
"1801","19","Journal Club","2013-10-30 15:00:00","2013-10-30 16:00:00","SAS 1220","Chetak Hossain",NULL,"NCSU",NULL,NULL,"Chetak Hossain will lead a journal club discussion on the paper &quot;An Area-to-Inv Bijection Between Dyck Paths and 312-avoiding Permutations&quot; by Jason Bandlow and Kendra Killpatrick, available at http://www.combinatorics.org/ojs/index.php/eljc/article/view/v8i1r40/pdf","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t25g61d5hcf2avtikas7vs2c24","2013-10-16 19:40:53",NULL
"1803","23","Transition to Teaching","2013-10-25 15:00:00","2013-10-25 16:00:00","SAS 4201","Math Department Senior Graduate Students",NULL,"NC State","Mansoor Haider",NULL,"There are many challenges as early graduate students make the transition from student to lecture assistant to teaching their own courses. A panel of senior graduate students will talk about how they navigated these experiences and what resources the department offers to assist people as they start this process. We welcome any and all questions related to first time teaching experiences.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hqhihrprt01uqausmlqsjp2e84","2013-10-17 08:23:31",NULL
"1805","6","Mathematical Methods for Processing Geospatial Image Data","2013-10-23 16:00:00","2013-10-23 17:00:00","SAS 4201","Bob Plemmons","http://www.wfu.edu/~plemmons","Wake Forest University","Moody Chu",NULL,"The science of optical remote sensing for geospatial applications includes aerial, satellite, and spacecraft observations of scenes or targets. Applications abound in various fields such as environmental remote sensing, monitoring chemical/oil spills, and object discrimination. Various diverse sensing modalities are useful, and a variety of types of on-board sensors are employed for data collection. The optical sensing modalities we are concerned with are Hyperspectral (HSI) imaging and Light Detection and Ranging (LiDAR), which generate massive amounts of data. HSI sensing collects information across a wide range of the electromagnetic spectrum while LiDAR is a remote sensing technology that collects RGB data while measuring distance by illuminating a target area with lasers and analyzing the reflected light. We first provide an overview of optical remote sensing methods and applications, with a concentration on HSI. We briefly discuss some recent mathematical techniques for HSI and LiDAR data fusion, geometric feature and pattern representation based on level set methods, classification, target detection and identification. Illustrations of the algorithms are provided on both simulated and real data. We then concentrate on recent work involving wavelength dependent hyperspectral PSF estimation and associated joint deblurring and sparse unmixing using alternating direction method of multipliers (ADMM) optimization for convex inverse problems. This is joint work with Peter Zhang at Wake Forest, and colleagues at Boeing, Duke and Emory, to be listed in the presentation.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l256a0eqjcift6sjfuhmk2snok","2013-10-17 11:20:43",NULL
"1807","15","Working in Industry: My Experiences in MathWorks","2013-10-21 13:30:00","2013-10-21 14:20:00","SAS 4201","Jill Reese",NULL,"MathWorks",NULL,NULL,"Dr. Jill Reese, a graduate of NCSU, will be speaking about her job at The MathWorks. Everyone is welcome to come hear her talk Working in Industry: My Experiences in MathWorks. SIAM will be providing lunch.","mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dnk5fidr6dpqcij6blp1qhlf50","2013-10-17 18:42:00","2013-10-18 08:41:23"
"1809","14","Departmental Tea and Cookies","2013-10-24 15:30:00","2013-10-24 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/4j824cve6qcaj289ohg04dogvg","2013-10-21 09:35:08",NULL
"1811","31","Linear waves over arbitrary periodic topographies","2013-11-06 11:15:00","2013-11-06 12:15:00","SAS 4201","Jie Yu","http://www4.ncsu.edu/~jyu4/","NC State",NULL,NULL,NULL,"nklowman","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9i16saeuu51ki5ep5d8efufv2o","2013-10-21 10:46:15","2013-10-22 10:05:57"
"1813","9","Professor","2013-10-29 16:15:00","2013-10-29 17:15:00","Cox 306","Michael Reed","http://fds.duke.edu/db/aas/math/reed","Duke, Mathematics",NULL,"http://www.ncsu.edu/biomath/abstracts/AbstractReed.pdf","Mathematical models of cell metabolism are useful for in silico experiments that shed light on various public health problems. The difficulties in designing such models will be discussed. Several applications will be given including: (1)folate metabolism, neural tube defects, and colon cancer (2) arsenic detoxification in Bangladesh (3) hepatotoxicity of acetaminophin.","msolufse","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/88909b3t1qr971bgfkh1u1b3b0","2013-10-21 13:30:47","2013-10-21 13:32:31"
"1815","3","Row and column correlation","2013-12-02 14:30:00","2013-12-02 15:30:00","SAS 4201","Clifford Smyth","http://www.uncg.edu/mat/people/people.php?username=cdsmyth","UNC Greensboro",NULL,NULL,"We prove the following result.  Suppose M is a random n by n 0-1 matrix with independent entries.  Suppose the probability that an entry in M is 1 depends only on the column of that entry.  Then, for each b, the probability that each column sum is bounded above by b is less than or equal to the probability that each row sum is bounded above by b.  Our proof uses Lagrangian analysis to get an arithmetic-geometric mean type inequality.  We also must determine when products of truncated binomial expansions dominate other such expressions coefficient by coefficient.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5gstdo0fcasi8qbu997gkbf40o","2013-10-25 10:30:56","2013-11-20 21:05:17"
"1817","26","Two-fluid flow in a capillary tube","2013-10-28 16:00:00","2013-10-28 17:00:00","SAS 4201","Melissa Strait",NULL,NULL,NULL,NULL,"A phase field model for two-phase flow in a capillary tube, developed by Cueto-Felgueroso and Juanes, results in a PDE with higher-order terms. We find traveling wave solutions of the PDE and determine a bound on parameters to obtain physically relevant solutions. We observe that the traveling wave height decreases monotonically with the capillary number and that the traveling wave height corresponds to the height of the plateaus seen in PDE simulations. We also compare results against classical experiments of G.I. Taylor.  This is joint work with Michael Shearer, Rachel Levy, Ruben Juanes, and Luis Cueto-Felgueroso.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/51cqg9elhbcbi19ftaukjihf78","2013-10-27 21:06:06",NULL
"1819","34","The dynamics of alternative pathways to compensatory substitution","2013-10-30 10:00:00","2013-10-30 11:15:00","SAS 4201","Chris Nasrallah","http://statgen.ncsu.edu/nasrallah/","NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/agg63182h0k1caenn1dmvnvh7s","2013-10-28 08:53:07",NULL
"1821","28","AWM Weekly Ladies Lunch","2013-10-31 12:30:00","2013-10-31 13:30:00","Undergraduate Lounge 2nd floor of SAS",NULL,NULL,NULL,NULL,NULL,NULL,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n9jgu8dijpe6p68c0502k9tvss","2013-10-31 12:28:04",NULL
"1823","34","Tertiary structures informing genome-wide receptor-ligand interactions","2013-11-06 10:00:00","2013-11-06 11:15:00","SAS 4201","Peter DiGennaro",NULL,"NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uj0f2upuctf4t8vn46260nlif8","2013-11-04 08:55:31","2013-11-04 13:14:12"
"1825","14","Departmental Tea and Cookies","2013-11-07 15:30:00","2013-11-07 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7rlo3lbr36qcv5eqpbm6u31ea4","2013-11-04 10:00:47",NULL
"1827","28","AWM Weekly Ladies Lunch","2013-11-07 12:30:00","2013-11-07 13:30:00","Undergraduate Lounge 2nd floor of SAS",NULL,NULL,NULL,NULL,NULL,NULL,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1g6n3pbjl7o4rir2901enntnus","2013-11-04 10:10:14","2013-11-04 10:10:26"
"1829","19","TBA","2013-11-06 15:00:00","2013-11-06 16:00:00","SAS 1220","Emily Barnard",NULL,"NCSU",NULL,NULL,"TBA","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uq8aqnhdosirhr2ips0b88p54s","2013-11-04 12:31:42",NULL
"1831","21","The Changing Climate of Weather Prognostication: The Irony of Uncertainty Leader to Better Forecasts","2013-12-04 19:00:00","2013-12-04 20:00:00","James B Hunt Library on NCSU Centennial Campus","Greg Fishel",NULL,"Capitol Broadcasting Companys chief meteorologist",NULL,"http://www.samsi.info/activities/seminars/other-seminars-and-lectures/changing-climate-weather-prognostication-irony-uncer",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/eec1tr9fmie85ko8tsp90epqns","2013-11-05 10:28:02","2013-11-05 10:53:24"
"1833","3","Super Schur functions and domino tilings","2013-12-09 14:30:00","2013-12-09 15:30:00","SAS 4201","Sylvie Corteel","http://www.liafa.jussieu.fr/~corteel/","CNRS, Universite Paris Diderot",NULL,NULL,"In this work we want to enumerate infinite families of domino tilings in a strip that we call steep tilings. To do this we use bijective combinatorics, vertex operators, Schur processes defined by Okounkov and Reshetikin and the combinatorics of Super-Schur functions due to Francesco Brenti. The key ingredient are the generalizations of the Cauchy identities for Super-Schur functions. This allows us to count the tilings, generate them randomly and compute their limit shapes. These tilings include the tilings of the Aztec diamond and the pyramid partitions, which are related to Donaldson-Thomas invariants of orbifolds thanks to some work of Ben Young. This is joint work with Jeremie Bouttier and Guillaume Chapuy for the combinatorics and also Cedric Boutillier, Sanjay Ramassamy and Mirjana Vuletic for the asymptotics.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9topioem9c39src0g8dgbmrli8","2013-11-07 09:58:29","2013-12-02 19:54:39"
"1837","26",NULL,"2013-11-01 16:00:00","2013-11-01 17:00:00","SAS 4201","Kaska Adoteye Ahlam Elashegh",NULL,"NC State",NULL,NULL,"Kaska:Title:  Qualitative Behavior of a HIV Distribution Model With VaccinesAbstract:  In this talk we will demonstrate a dynamical systems model for the distribution of HIV in a population. The model also encompasses the use of two different types of vaccines against HIV: a preventative vaccine and a therapeutic vaccine. The vaccines are treated as control parameters in the model. We will analyze the qualitative and asymptotic behavior of the model, as well as look at the effect that each type of vaccine has on the model. This analysis is then expanded upon when looking at the model with data from San Franciscos homosexual population in 1987.Ahlam: Title:  Mathematical and Computational Mixture Models for Cartilage Regeneration in Cell-Seeded ScaffoldsAbstract:  Articular cartilage is the soft tissue that can be found in articulating joints such as the knee, shoulder and hip. Cartilage degeneration due to osteoarthritis or injury can lead to osteochondral defects in the cartilage layer. Tissue engineering applications based on chondrocyte-biomaterial systems have the potential to regenerate cartilage in a controlled environment. Multiphasic continuum mixture mathematical models are used to describe both biomechanical deformation and transport of water and solutes in articular cartilage regeneration in cell-seeded scaffold. A recent experimental study indicated that evolving porosity may strongly influence key functional outcomes. We developed spatio-temporal continuum mixture models that govern interactions among biomechanical, biophysical, chemical, and biological phenomena during cartilage regeneration in cell seeded scaffold. The governing equations of our models are formulated by considering balance of mass, balance of momentum, and by assuming that the mixture is saturated and that its phases are intrinsically incompressible. In the talk the model formulation and results will be discussed.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6sv3f92o1luqkf9qom22tpgr64","2013-11-08 09:51:14",NULL
"1839","14","NC State Mathematics Department Graduation Ceremony","2013-12-18 15:00:00","2013-12-18 17:00:00","SAS 2203",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/345i48ot8iiiuf18qote1nui8g","2013-11-08 11:05:19",NULL
"1841","27","SIAM Conference on the Life Sciences","2014-08-04 08:00:00","2014-08-07 13:00:00","Charlotte North Carolina USA",NULL,NULL,NULL,"Mette Olufsen","http://www.siam.org/meetings/ls14/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hq4hsacghis406k9ld4im77nb0","2013-11-08 11:17:43","2013-11-12 10:42:56"
"1843","27","39th International Symposium on Symbolic and Algebraic Computation","2014-07-23 08:00:00","2014-07-25 13:00:00","Kobe Japan",NULL,NULL,NULL,"Agnes Szanto","http://www.issac-symposium.org/2014/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8scgck4usml11he7n3fi5pge08","2013-11-08 11:20:53","2013-11-12 10:42:32"
"1845","27","Foundations of Computational Mathematics Conference","2014-12-11 08:00:00","2014-12-20 13:00:00","Montevideo Uruguay",NULL,NULL,NULL,"Agnes Szanto","http://www.fing.edu.uy/~jana/www2/focm_2014.html",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hrmgjvcl5emu7sc87ce1qn4feg","2013-11-08 11:22:47","2013-11-12 10:43:29"
"1847","14","Departmental Tea and Cookies","2013-11-13 14:30:00","2013-11-13 15:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/67hlpok6bkmi27dhh0jpgc6u2s","2013-11-11 09:11:58",NULL
"1849","28","AWM Weekly Ladies Lunch","2013-11-14 12:30:00","2013-11-14 13:30:00","Undergraduate Lounge 2nd floor of SAS",NULL,NULL,NULL,NULL,NULL,NULL,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/t5sd53dh0a2o7p7puo33vpbcr4","2013-11-11 15:12:19",NULL
"1851","28","AWM Weekly Ladies Lunch","2013-11-21 12:30:00","2013-11-21 13:30:00","Undergraduate Lounge 2nd floor of SAS",NULL,NULL,NULL,NULL,NULL,NULL,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p9qc46s29fk9c7qjdpdi666q7k","2013-11-11 15:13:09",NULL
"1853","27","Householder Symposium XIX","2014-06-08 08:00:00","2014-06-13 17:00:00","Spa Belgium",NULL,NULL,NULL,"Ilse Ipsen","http://sites.uclouvain.be/HHXIX/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/03loeh4u3pu83a988egie5q9m8","2013-11-12 11:25:37","2013-11-12 11:26:25"
"1855","23","Preparing for Interviews at the Joint Math Meetings","2013-11-22 15:00:00","2013-11-22 16:00:00","SAS 4201","Faculty and  Postdoc Panel",NULL,"NC State","Mansoor Haider",NULL,"We will share experiences and discuss strategies in preparation for the Mathematical Sciences Employment Center at the 2014 Joint Math Meetings in Baltimore, MD.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kksb70k39a6d7mmu9di1a51f40","2013-11-12 11:53:31","2013-11-12 11:54:12"
"1857","27","Difference schemes and applications","2013-05-27 08:00:00","2013-05-31 17:00:00","Moscow Russia",NULL,NULL,NULL,"Semyon Tsynkov","http://www.kiam.ru/ryabenkii2013/en/index.html",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8q4f2ee8q67erd9337bmo5b99g","2013-11-12 11:54:27",NULL
"1859","27","Algebraic Statistics in the Alleghenies at Penn State","2012-06-09 08:00:00","2012-06-15 17:00:00","State College Pennsylvania",NULL,NULL,NULL,"Seth Sullivant","http://www.jasonmorton.com/aspsu2012/index.html",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6bo8qc0hmf1ttlcipapugrk5so","2013-11-12 12:01:51",NULL
"1861","27","Algebraic Statistics at IIT","2014-05-19 08:00:00","2014-05-22 17:00:00","Chicago Illinois",NULL,NULL,NULL,"Seth Sullivant","http://mypages.iit.edu/7Eas2014/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/00bq3ej7m42092r4bjrn35oek4","2013-11-12 12:05:35",NULL
"1863","27","SIAM Meeting on Applied Algebraic Geometry","2011-10-06 08:00:00","2011-10-09 17:00:00","Raleigh North Carolina",NULL,NULL,NULL,"Seth Sullivant","http://www.siam.org/meetings/ag11/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r84sbhodv4nkevh7feubr0n8ok","2013-11-12 12:07:45",NULL
"1865","27","2010 Workshop on Control and Optimization with Differential-Algebraic Constraints","2010-10-24 08:00:00","2010-10-29 17:00:00","Banff International Research Station",NULL,NULL,NULL,"Stephen Campbell","http://www.birs.ca/events/2010/5-day-workshops/10w5029",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0c9rcban58ke0roeokvmtmq378","2013-11-12 13:06:25",NULL
"1869","27","13th Copper Mountain Conference on Iterative Methods","2014-04-06 08:00:00","2014-04-11 17:00:00","Copper Mountain Colorado",,,,"CT Kelley","http://grandmaster.colorado.edu/~copper/2014/",,"schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/oss834s5jrbpsfqfu7nc68j6oc","2013-11-12 13:25:32","2014-01-07 11:15:48"
"1873","27","The 12th International Symposium on Distributed Computing and Applications to Business, Engineering and Science","2013-09-02 08:00:00","2013-09-04 17:00:00","London UK",NULL,NULL,NULL,"CT Kelley","http://sec.kingston.ac.uk/2013dcabes/invited.html",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/u4k0mq3cs40ln528d60gkcougg","2013-11-12 13:31:45",NULL
"1875","27","Combinatorial Representation Theory Workshop","2014-04-21 08:00:00","2014-04-25 17:00:00","Montreal Canada",NULL,NULL,NULL,"Kailash Misra","http://www.crm.umontreal.ca/2014/Combinatorial14/index_e.php",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c1ssji71tfksn2vn0jm3u0apvs","2013-11-12 13:38:09",NULL
"1877","27","Representation Theory and Related Topics","2014-08-06 08:00:00","2014-08-09 17:00:00","Daegu South Korea",NULL,NULL,NULL,"Kailash Misra","https://sites.google.com/site/icm2014satelliterepn/",NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pqcb4p4al0acti0up28r21632o","2013-11-12 13:42:43",NULL
"1879","26","Gravity Currents with Residual Trapping","2013-11-18 16:00:00","2013-11-18 17:00:00","SAS 4201","Elisabeth Brown",NULL,"NC State",NULL,NULL,"Carbon capture and storage involves capturing carbon dioxide released from industrial processes and storing it in underground brine aquifers. As the carbon dioxide plume flows through the permeable rock, some of it becomes trapped in pore spaces this process is called residual trapping and causes a discontinuity in this PDEs flux. We investigate a model for the flow of supercritical carbon dioxide in a brine aquifer and study how the modeling of residual trapping impacts the solutions of various initial plumes. A conjecture is presented regarding a global solution to this PDE for any initial condition.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jjhpcot6gtt05prf44r4llciks","2013-11-17 18:47:13",NULL
"1881","14","Departmental Tea and Cookies","2013-11-21 15:30:00","2013-11-21 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ajh6vr6pftkcr49sjrnjr3a7bo","2013-11-18 11:10:58",NULL
"1883","26","Verification techniques for Bayesian model calibration","2013-11-25 16:00:00","2013-11-25 17:00:00","SAS 4201","Mami Wentworth",NULL,"NC State",NULL,NULL,"We discuss techniques to verify the accuracy of parameter or input densities constructed using Bayesian inference. The posterior distribution can be computed using the prior distribution, likelihood and possibly high-dimensional integration. We first employ a direct method to compute the posterior using the formula directly via a numerical quadrature. We then compare the direct method to two adaptive methods, Delayed Rejection Adaptive Metropolis (DRAM) and Differential Evolution Adaptive Metropolis (DREAM). These methods employ a MCMC algorithm and efficiently estimate model parameters without involving high-dimensional integration. We use a steady-state heat model as an example to demonstrate how these methods construct densities and compare their accuracy.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lrad4e31f7t0kv5jh14t61lhi4","2013-11-19 17:44:55",NULL
"1887","34","The Space of Phylogenetic Trees","2014-01-08 10:00:00","2014-01-08 11:15:00","SAS 4201","Katherine St. John","http://comet.lehman.cuny.edu/stjohn/research/index.html","CUNY Lehman College",NULL,NULL,"Phylogenies, or evolutionary histories, play a central role in modern biology, illustrating the interrelationships between species, and also aiding the prediction of structural, physiological, and biochemical properties.  The reconstruction of the underlying evolutionary history from a set of morphological characters or bimolecular sequences is computationally hard under the optimality criteria favored by biologists.  A simple representation for a phylogeny is a rooted, binary tree, where the leaves represent the species, and internal nodes represent their hypothetical ancestors.  This talk will focus on some of the elegant questions that arise from modeling, visualizing, and searching the space of phylogenetic trees.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qc2u4o1l17he9tc9buuqmpcgs4","2013-11-20 16:58:21","2013-11-20 17:13:00"
"1889","9","Backward Bifurcation and Global Stability Analysis of an Epidemic Model with Partial Immunity","2013-11-26 16:15:00","2013-11-26 17:15:00","Cox 306","Salisu Garba",NULL,"Univ of Pretoria, Dept of Mathematics",NULL,NULL,"Backward Bifurcation and Global Stability Analysis of an Epidemic Model with Partial ImmunitySalisu M. GarbaWe present a deterministic model for two stage bovine tuberculosis (BTB) in African buffalo. Analysis of the model with standard incidence formulation reveals that the model exhibits a phenomenon of backward bifurcation, where a stable disease-free equilibrium (DFE) co-exists with a stable endemic equilibrium (EE) when the associated reproduction number is less than unity (Rv  1). It is shown that, this phenomenon of backward bifurcation can be removed by substituting the associated standard incidence function with a mass action incidence. Further, it is proved that this phenomenon can also be removed if either all recruited buffaloes are vaccinated or a fraction of them are vaccinated and the infectivity of seropositive susceptible buffalo is negligible. In both cases, it is shown, using Lyapunov function theory and LaSalle Invariance Principle, that the DFE of the model is globally asymptotically stable when Rv  1. Furthermore, it is shown using threshold analysis approach that a vaccine could have a positive impact provided the vaccine efficacy and vaccine coverage are high enough.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/n5n5o2jltf069kqrl28qak2q8c","2013-11-22 08:09:26",NULL
"1890","22","Mathematics Undergraduate Research Presentations","2013-12-02 16:00:00","2013-12-02 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,NULL,"1.  Steven Lindsey Title :  Tournament Solutions and the Banks Set Abstract : Tournaments are familiar mechanisms for finding the winner from a set of alternatives. We will discuss elimination style tournaments where there is an agenda of head to head contests. In this situation the placement of the candidates has a huge impact on the outcome of the winner. What were interested in is what candidates could win if we examine all of the possible agendas by permuting the order of the candidates. There are two different ways voters can behave that could lead to different winners and instead of going through all of the possible agendas for both ways we want to find an easier method that could determine all of our possible winners. -------------------------------------------------------------------------------------2. Lillian Faye Pasley Title :  On Commutators of Matrices over Rings Abstract :  We are interested with considering Khurana and Lams question: can every nxn upper triangular matrix over any ring be expressed as a generalized commutator?  A counterexample for the 2x2 case is given using an alternative method. An original proof for traceless upper triangular matrices is also explained.  -------------------------------------------------------------------------------------3.  Lauren WilliamsTitle :  Coronary Artery Bypass Grafting Surgerys Effect on Functional Status and SurvivalAbstract : Today, heart disease is the leading cause of death for both men and women in the United States with coronary heart disease as the most common type, killing more than 385,000 people annually. An open-heart surgery known as Coronary Artery Bypass Grafting, CABG, has become increasingly prevalent, improving blood flow to the heart, with the goals of improving ones quality of life and survival rate. The conclusions obtained from statistically and mathematically analyzing associations between given characteristics of a patient, and the probability that they had been given the CABG surgery, can be used as scientific evidence by medical professionals in order to adjust medical practices and administer more successful procedures and treatment plans. Analyzing the resulting impacts of the CABG surgery on ones ability to carry out daily functions and ones long-term survival rate is equally as important, providing those who administer these procedures with the scientific knowledge to determine when a given surgery is most appropriate and advantageous. Mathematicians and statisticians collaborate in order to effective apply mathematical modeling techniques to the statistical analyses and most importantly, ensure that the computations are accurately representing the data. With the large amount of medical data that exists today, this collaboration will increasingly become an integral part of the medical research process.  -------------------------------------------------------------------------------------4.  Samantha ZuberTitle : Investigating Volume Conservation in Gut Morphogenesis Abstract : Over the course of evolution, the gut has evolved to process the different nutrients available from diverse diets.  Consequently, the length of the gut tube varies in different species in order to facilitate adequate nutrient absorption in different ecological niches.  To begin to understand how gut length variation occurs, our group focused on identifying the mechanisms that control gut elongation during development.  We chose to study the guts of two anuran tadpoles: the carnivorous Lepidobatrachus laevis and the omnivorous Xenopus laevis.  Previous research suggests that the rearrangement, rather than the proliferation, of existing gut cells contributes to the elongation of the embryonic gut tube, but it is unknown whether this is the sole process driving elongation.  If so, we hypothesized that volume would be conserved as the gut elongates.  Therefore, we fixed Xenopus and Lepidobatrachus embryos at four critical developmental stages spanning embryonic gut lengthening and dissected their guts into smaller pieces under a Lumar microscope.  Then, we photographed the individual pieces with AxioVision software and measured the split length and cross sectional area of each gut piece using ImageJ software.  Using volumetric equations for a cylinder and/or a frustum, we then calculated each pieces volume.  We found that both species guts maintained their volumes across the measured stages.  Thus, our data affirms the hypothesis that volume is conserved during gut elongation and it can be inferred that radial intercalation is the major process driving gut lengthening during development.  Variation in embryonic gut cell rearrangements may underlie the evolution of different gut morphologies.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9792bs15f51660jfn41krklo84","2013-12-02 10:02:37","2013-12-02 10:04:58"
"1894","14","Dr. Franke Retirement Reception","2013-12-04 15:00:00","2013-12-04 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bkq958v1cesl1om5446pffrt8g","2013-12-03 10:23:20",NULL
"1896","28","AWM Weekly Ladies Lunch","2013-12-05 12:30:00","2013-12-05 13:30:00","Undergraduate Lounge 2nd floor of SAS",NULL,NULL,NULL,NULL,NULL,NULL,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/e8n9vqgrjsl3osg2fjcphb1sk4","2013-12-03 11:27:27",NULL
"1898","23","Experiences from the Joint Math Meetings","2014-01-24 15:00:00","2014-01-24 16:00:00","SAS 4201","Graduate Student Panel",NULL,"NC State","Mansoor Haider",NULL,NULL,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b7ll2vkkvs7d6u1ik592rr20c8","2013-12-04 10:46:51",NULL
"1902","21","Graduate Recruitment Weekend","2014-02-28 09:00:00","2014-03-01 17:00:00","SAS 4201",NULL,NULL,NULL,"Mansoor Haider",NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0tdq9pgip5s99a8snvutb5vcu0","2013-12-04 10:59:36","2013-12-10 09:56:39"
"1906","2","Fast direct solvers for linear partial differential equations","2014-01-13 16:00:00","2014-01-13 17:00:00","SAS 4201","Adrianna Gillman","http://www.math.dartmouth.edu/~gillmana/","Dartmouth College","Ilse Ipsen",NULL,"Fast direct solvers construct an inverse of a linear system for a cost that scales linearly or nearly linearly with respect to the number of unknowns, unlike e.g. Gaussian elimination which scales cubically and is thus not viable for very large linear systems. The fast direct methods presented in this talk are designed for the linear systems arising from the discretization of linear partial differential equations. These methods are more robust, versatile and stable than iterative schemes.  Since an inverse is computed, additional right-hand sides can be processed rapidly.  The talk will give the audience a brief introduction to the core ideas, an overview of recent advancements, and it will conclude with a sampling of challenging application examples.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7jbpschvif6ge8b77m6373opvs","2013-12-06 13:46:08","2013-12-16 10:22:54"
"1908","14","Towards the control of multiscale stochastic systems","2013-01-07 16:00:00","2013-01-07 17:00:00","SAS","Tao Molei","http://cims.nyu.edu/~mtao/","Courant Institute, New York University",NULL,NULL,"Motivated by rich applications in science and engineering, I am interested in controlling systems that are characterized by multiple scales, geometric structures, and randomness. This talk will focus on my first two steps   this goal.brThe first step is to be able to simulate these systems. We developed integrators that do not resolve fast scales in these systems but still capture their effective contributions. These integrators require no identification of underlying slow variables or processes, and therefore work for a broad spectrum of systems (including stiff ODEs, SDEs and PDEs). They also numerically preserve intrinsic geometric structures (e.g., symplecticity, invariant distribution, and other conservation laws), and this leads to improved long time accuracy.brThe second step is to understand what noises can do and utilize them. We quantify noise-induced transitions by optimizing probabilities given by Freidlin-Wentzell large deviation theory. In gradient systems, transitions between metastable states were known to cross saddle points. We investigate nongradient systems, and show transitions may instead cross unstable periodic orbits. Numerical tools for identifying periodic orbits and for computing transition paths are proposed. I will also describe how these results help design control strategies.","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n2mmutccj60vbtakq5g8pbb5p8","2013-12-06 15:04:49",NULL
"1910","2","Towards the control of multiscale stochastic systems","2014-01-07 16:00:00","2014-01-07 17:00:00","SAS 4201","Molei Tao","http://cims.nyu.edu/~mtao/","Courant Institute, New York University","Ralph Smith",,"Motivated by rich applications in science and engineering, I am interested in controlling systems that are characterized by multiple scales, geometric structures, and randomness. This talk will focus on my first two steps towards this goal.The first step is to be able to simulate these systems. We developed integrators that do not resolve fast scales in these systems but still capture their effective contributions. These integrators require no identification of underlying slow variables or processes, and therefore work for a broad spectrum of systems (including stiff ODEs, SDEs and PDEs). They also numerically preserve intrinsic geometric structures (e.g., symplecticity, invariant distribution, and other conservation laws), and this leads to improved long time accuracy.The second step is to understand what noises can do and utilize them. We quantify noise-induced transitions by optimizing probabilities given by Freidlin-Wentzell large deviation theory. In gradient systems, transitions between metastable states were known to cross saddle points. We investigate nongradient systems, and show transitions may instead cross unstable periodic orbits. Numerical tools for identifying periodic orbits and for computing transition paths are proposed. I will also describe how these results help design control strategies.","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9d6mm81pep7tqht8bmq326qtic","2013-12-06 15:07:21","2014-01-06 07:00:28"
"1912","38","The Stochastic Clustering Algorithm: Efficiency and Application - advised by Carl Meyer","2013-12-20 13:00:00","2013-12-20 15:00:00","SAS 3282","Ralph Abbey",NULL,"NC State",NULL,NULL,NULL,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/cppsic8erf4ahtjst9h7t75ir8","2013-12-09 14:51:37","2013-12-09 16:46:56"
"1914","14","Spring 2014 Mathematics Departmental Meeting","2014-01-06 16:00:00","2014-01-06 17:00:00","SAS 1102",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sc9gg89vp06srns92n1980upec","2013-12-10 09:53:43",NULL
"1916","14","Spring 2014 Departmental Meeting Reception","2014-01-06 15:30:00","2014-01-06 16:00:00","SAS 4104",NULL,NULL,NULL,NULL,NULL,NULL,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9r7e7vf0kcl2lbfnlndagjlios","2013-12-10 09:55:29",NULL
"1918","2","Sparse Matrix Algorithms: Combinatorics  Numerical Methods  Applications","2014-01-08 16:00:00","2014-01-08 17:00:00","SAS 4201","Tim Davis","http://www.cise.ufl.edu/~davis/welcome.html","University of Florida","Tim Kelley","http://www.math.ncsu.edu/davis_abs.pdf","Sparse matrix algorithms lie in the intersection of graph theory
and numerical linear algebra, and are a key component of
high-performance combinatorial scientific computing.  This talk
highlights four of my contributions in this domain, ranging from
theory and algorithms to reliable mathematical software and its impact on
applications:

    (1) Sparse Cholesky update/downdate
    (2) Approximate minimum degree
    (3) Unsymmetric multifrontal method for sparse LU factorization
    (4) Multifrontal sparse QR factorization

The design of these algorithms takes into account the many
applications that rely on them, including MATLAB (x=A\b when A is
sparse), Mathematica, Google (Street View, Photo Tours, and 3D
Earth), Octave, ANSYS, Cadence, MSC NASTRAN, Mentor Graphics, and
many other commercial, academic, and government lab applications in
finite element methods, mathematical optimization, circuit
simulation, VLSI design, robotics, graphics, computer vision,
structural engineering, and geophysical modeling.

This talk also presents my current work in GPU-based heterogeneous
high-performance parallel computing for sparse multifrontal methods.
The method assembles and factorizes all frontal matrices on the GPU,
without the need to transfer large amounts of data between the GPU
and CPU.  The sparse matrix is shipped to the GPU and the final
factors are retrieved when it completes.  A novel scheduling
algorithm for communication-avoiding dense QR exposes a higher
degree of parallelism than previous methods.  Our research prototype
exceeds 80 GFlops for a large sparse QR factorization on the NVIDIA
Fermi GPU, with a 5x to 8x speedup for large problems, as compared
to the highly-optimized multicore sparse QR on the CPU.

My goal for future research is to continue to create algorithms and
software with deep impact in applications of computational mathematics.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1ptr6o5mj1djh84jtuhmcnmlo8","2013-12-10 15:13:13","2013-12-16 10:21:19"
"1921","4",NULL,"2013-03-05 15:00:00","2013-03-05 16:00:00","SAS 4201","Douglas Baldwin","http://www.douglasbaldwin.com/","University of Colorado, Boulder","Mark Hoefer",NULL,NULL,"mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l1je8o4mjoofidiafirb0pa96g","2013-12-16 11:43:41",NULL
"1924","4","Dispersive shock waves and shallow ocean-wave line-soliton interactions","2014-02-26 15:00:00","2014-02-26 16:00:00","SAS 4201","Douglas Baldwin","http://www.douglasbaldwin.com/","University of Colorado at Boulder","Mark Hoefer",,"Many physical phenomena are understood and modeled with nonlinear partial differential equations (PDEs). A special subclass of these nonlinear PDEs has stable localized waves -- called solitons -- with important applications in engineering and physics. Ill talk about two such applications: dispersive shock waves and shallow ocean-wave line-soliton interactions.

Dispersive shock waves (DSWs) occur in systems dominated by weak dispersion and weak nonlinearity. The Korteweg-de Vries (KdV) equation is a universal model for phenomena with weak dispersion and weak quadratic nonlinearity. Ill show that the long-time asymptotic solution of the KdV equation for general step-like data is a single-phase DSW; the boundary data determine its form and the initial data determine its position. I find this asymptotic solution using the inverse scattering transform (IST) and matched-asymptotic expansions.

Ocean waves are complex and often turbulent. While most ocean-wave interactions are essentially linear, sometimes two or more waves interact in a nonlinear way. For example, two or more waves can interact and yield waves that are much taller than the sum of the original wave heights. Most of these nonlinear interactions look like an X or a Y or an H from above; much less frequently, several lines appear on each side of the interaction region. It was thought that such nonlinear interactions are rare events: they are not. Ill show photographs and videos of such interactions, which occur every day, close to low tide, on two flat beaches that are about 2,000 km apart. These interactions are related to the analytic, soliton solutions of the Kadomtsev-Petviashvili equation, which extends the KdV equation to include transverse effects. On a much larger scale, tsunami waves can merge in similar ways.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/81q5u22rtcij4atd7j306e64eg","2013-12-16 11:45:41","2014-02-19 10:55:33"
"1927","2","Numerical Linear Algebra Aspects of Adaptive Finite Element Methods for PDE Eigenvalue Problems","2014-01-10 16:00:00","2014-01-10 17:00:00","SAS 4201","Agnieszka Miedlar","http://www.math.tu-berlin.de/fachgebiete_ag_modnumdiff/fg_numerische_mathematik/v-menue/mitarbeiter/agnieszka_miedlar/home/","Technical University Berlin, Germany","Ilse Ipsen","http://www4.ncsu.edu/~ipsen/miedlar_abs.pdf",NULL,"ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/asurce3ars62sh8b08ohhfr1jc","2013-12-20 11:52:00","2014-01-04 09:28:54"
"1930","3","Quasisymmetric hook Schur functions","2014-03-24 14:30:00","2014-03-24 15:30:00","SAS 4201","Sarah Mason","http://users.wfu.edu/masonsk/","Wake Forest University",,,"Hook Schur functions are a class of symmetric functions (in two sets of variables) introduced in 1987 by Berele and Regev to prove a generalization of Weyls &quot;Strip Theorem&quot;.  We introduce a generalization of hook Schur functions to the space of quasisymmetric functions and prove that several useful properties of the hook Schur functions remain true in the quasisymmetric setting.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nhe3p0i1509c141rv5sbpd2394","2013-12-26 11:53:21","2014-02-19 10:03:23"
"1931","36",,"2014-01-31 15:00:00","2014-01-31 16:00:00","SAS 4201","Moody Chu and Hien Tran",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v5mkj6i5rqv6p31uirsmoc3qgc","2013-12-30 11:07:44","2014-01-07 15:16:53"
"1934","36",,"2014-04-04 15:00:00","2014-04-04 16:00:00","SAS 4201","Patricia Hersh and Steve Campbell",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/1i46a2vh96t3hvk1r9n36jhvn0","2013-12-30 11:08:41","2014-03-31 08:52:46"
"1937","36",NULL,"2014-04-11 15:00:00","2014-04-11 16:00:00","SAS 4201","Naihuan Jing and Mette Olufsen",NULL,"NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5ruoipia8bfpjubd4s54km60qs","2013-12-30 11:09:57",NULL
"1943","36",NULL,"2014-03-21 15:00:00","2014-03-21 16:00:00","SAS 4201","Hoon Hong and Dmitry Zenkov",NULL,"NC State",NULL,NULL,NULL,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/pnh8elagcm9sb7m7lf05q81vso","2013-12-31 09:07:03",NULL
"1949","1","Continuous Analogues of Matrix Factorizations","2014-03-31 16:00:00","2014-03-31 17:00:00","SAS 1102","L. N. Trefethen","http://people.maths.ox.ac.uk/trefethen/","Oxford University","Michael Shearer",,"The algorithms of numerical linear algebra are tied to familiar matrix factorizations such as LU, Cholesky, QR, and SVD.  What happens to these factorizations if the discrete matrix becomes continuous in one dimension (a &quotquasimatrix&quot) or both (a &quotcmatrix&quot)?  Such questions have become of practical importance to us recently in the Chebfun software project, whose aim is to enable numerical computation with functions of continuous variables. This talk will present some answers, including a discussion of the analogues of pivoting and triangular structure for continuous objects. Chebfun demonstrations will be included some challenging questions of analysis will be touched upon.  This is joint work with Alex Townsend.","dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/bk5ah0ied5cvjdofvn2m44sab4","2014-01-03 09:31:48","2014-01-05 19:32:26"
"1958","1","The eye as a window on the body: mathematical modeling of retinal blood flow","2014-02-20 16:00:00","2014-02-20 17:00:00","SAS 1102","Giovanna Guidoboni","http://www.math.iupui.edu/~gguidobo","Indiana University and Purdue University at Indianapolis","Lorena Bociu",,"The eye is the only place in the human body where blood flow and systemic vascular features can be observed and measured easily and non-invasively down to the capillary level. Numerous clinical studies have shown correlations between alterations in retinal blood flow and ocular diseases (e.g. glaucoma, age-related macular degeneration, diabetic retinopathy), neurodegenerative diseases (e.g. Alzheimers disease, Parkinsons disease) and other systemic diseases (e.g. hypertension, diabetes). Thus deciphering the mechanisms governing retinal blood flow could be the key to the use of eye examinations as a non-invasive approach to diagnosis and continuous monitoring for many patients.

However, many factors influence ocular hemodynamics, including intraocular pressure (IOP), arterial blood pressure, and blood flow auto regulation. It is extremely challenging to single out their individual contributions during clinical and animal studies. In recent years we have been developing mathematical models to aid the interpretation of clinical data. In this talk we will present models describing (i) the blood flow in the retinal macro- and micro-vasculature, accounting for the IOP-induced deformation of the vessel walls (ii) the autoregulation of blood flow in the retina, accounting for the myogenic, shear-stress, CO2 and O2 responses and (iii) O2 transport, diffusion, and consumption in the retinal vasculature and tissue. Results will show how the synergy between mathematical modeling and clinical data allows estimation of the relative contribution of IOP, arterial blood pressure and blood flow autoregulation on retinal perfusion, and the sensitivity of retinal oxygenation to changes in blood pressure and hematocrit.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/86j9bnd3iig42o27fl0i1upkno","2014-01-06 16:47:38","2014-02-05 13:30:26"
"1961","36",,"2014-02-21 15:00:00","2014-02-21 16:00:00","SAS 4201","Sharon Lubkin and Bojko Bakalov",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nm2hl5prd14kb21ohb132q5tv0","2014-01-07 15:44:51","2014-02-14 11:32:09"
"1971","14","Departmental Tea and Cookies","2014-01-08 15:30:00","2014-01-08 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/msnfle9kgb0cugk9hlrgk5ot1s","2014-01-08 11:11:44",NULL
"1974","28","AWM Weekly Ladies Lunch","2014-01-15 12:30:00","2014-01-15 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/kcgvpje86el7vdkf06pctenbns","2014-01-08 13:37:50",NULL
"1977","28","AWM Weekly Ladies Lunch","2014-01-22 12:30:00","2014-01-22 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9rv6glbkf7ji23685elrpu4kb8","2014-01-08 13:38:57",NULL
"1980","28","AWM Weekly Ladies Lunch CANCELLED","2014-01-29 12:30:00","2014-01-29 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,"This weeks lunch is cancelled due to the weather.  See you next week!","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9rj5ssqh34oh8j2brcr774cgc8","2014-01-08 13:39:42","2014-01-29 08:50:17"
"1983","28","AWM Weekly Ladies Lunch","2014-02-05 12:30:00","2014-02-05 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5hsat0srbsockbsl6455am1afg","2014-01-08 13:40:20",NULL
"1986","28","AWM Weekly Ladies Lunch CANCELED","2014-02-12 12:30:00","2014-02-12 13:30:00",,,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0qoqegothmgdb3j36v420upi0c","2014-01-08 13:40:59","2014-02-12 10:00:30"
"1989","28","AWM Weekly Ladies Lunch","2014-02-19 12:30:00","2014-02-19 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0cctmluoa2qba8s41rdipmitso","2014-01-08 13:41:33",NULL
"1995","14","Departmental Tea and Cookies","2014-01-10 15:30:00","2014-01-10 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jr3lrnt18t4ashmj6f0ingnchc","2014-01-09 09:39:51",NULL
"2000","14","Departmental Tea and Cookies","2014-01-13 15:30:00","2014-01-13 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/l4m84u88pnek60a3ajkr32sj04","2014-01-13 09:41:23",NULL
"2003","4","Modeling Light Propagation in Luminescent Media","2014-02-19 15:00:00","2014-02-19 16:00:00","SAS 4201","Derya Sahin","http://campillos.ucmerced.edu/~dsahin/","University of California, Merced","Mark Hoefer",,"This study presents computational and physical modeling approaches to account for light propagation in luminescent random media. We use a statistical approach: Monte-Carlo simulations for photon transport and a deterministic approach: radiative transport theory. Both approaches account accurately for the multiple absorption and reemission of light at different wavelengths and for anisotropic luminescence. To test our approaches, we apply them to model light propagation in semiconductor-based luminescent solar concentrators (LSCs). Using measured luminescent data of semiconductor nanoparticles, the LSC performance is studied in detail, including its dependence on particle concentration and the anisotropy of the luminescence. The computational results for both approaches are compared with each other and found to agree qualitatively. The deterministic approach that we propose is a generalization of radiative transport theory for solving inelastic scattering problems, which we call as luminescent radiative transport theory. This theory has an advantage for analytic and computational modeling in the applications involving luminescent radiation. Also, we study the asymptotic solution of this luminescent radiative transport theory for optically-thick media. Physically, this corresponds to when the probability of reemission or photoluminescence quantum yield is close to unity. Using asymptotic methods, we derive a corrected diffusion approximation with associated boundary conditions and a boundary layer solution. The accuracy of this approach is verified for a plane-parallel slab problem. In particular, the reduced system captures accurately the reabsorption of light. The impacts of varying the Stokes shift and using experimentally measured luminescence data are also explored.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2pv4psf0c8iev28e09pe831d0o","2014-01-13 12:19:58","2014-02-12 09:24:23"
"2006","14","Departmental Tea and Cookies","2014-01-21 15:30:00","2014-01-21 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/95sfq656hjcn1oppq11cjpcvtg","2014-01-13 12:31:21",NULL
"2009","14","Departmental Tea and Cookies","2014-01-22 15:30:00","2014-01-22 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/4e0f00653ndccpcqe5djbk7k2k","2014-01-13 12:31:58",NULL
"2012","14","Departmental Tea and Cookies","2014-01-27 15:30:00","2014-01-27 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/71gglqgevenmsck2prbd99phng","2014-01-13 12:32:29",NULL
"2015","14","Departmental Tea and Cookies","2014-01-31 15:30:00","2014-01-31 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mtitmvt4ue34dffcj3aqcvc4s4","2014-01-13 12:32:57","2014-01-28 18:04:46"
"2024","14","Departmental Tea and Cookies","2014-02-03 15:30:00","2014-02-03 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vfm1nuuh17ultdsltlmpj0tufo","2014-01-13 12:34:28",NULL
"2027","14","Departmental Tea and Cookies","2014-02-04 15:30:00","2014-02-04 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pfji1kreabcn3pudutjn7j4jls","2014-01-13 12:34:49",NULL
"2030","14","Departmental Tea and Cookies","2014-02-06 15:30:00","2014-02-06 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9unetf9hsdp97666q9a4pi4osc","2014-01-13 12:35:18",NULL
"2036","14","Departmental Tea and Cookies","2014-02-20 15:30:00","2014-02-20 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sqvt2ft37mavmd5qk5h0m7r2vo","2014-01-13 12:36:26","2014-02-17 10:25:27"
"2039","14","Departmental Tea and Cookies","2014-02-17 15:00:00","2014-02-17 15:30:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8kmv80tpuii32slur6pg4adhko","2014-01-13 12:36:49","2014-02-17 09:42:58"
"2043","2","Topics in mathematical cell biology: applications to cell polarity and embryogenesis","2014-01-21 16:00:00","2014-01-21 17:00:00","SAS 4201","William Holmes","http://www.math.uci.edu/~wrholmes/","University of California, Irvine","Lloyd",,"I will give an overview of my work in mathematical cell biology.  First I will discuss topics related to polarity, specifically in the context of cell movement.  This and numerous other cell functions require identification a front and back (e.g. polarity).   In some cases this can form spontaneously and in others sufficiently large stimuli are required.  I will discuss a mechanistic theory for how cells might transition between these behaviors by modulating their sensitivity to external stimuli.  In order to address this and analyze the models being presented, I will describe a new bifurcation technique, the Local Perturbation Analysis, for analyzing complex, spatial biochemical networks.  Additionally, I will discuss work related to early development of the mammalian embryo.  A vital first step in this process is the formation of an early placenta prior to implantation.  I will discuss a stochastic model of this spatial patterning event and show that systemic noise, rather than being a hindrance, is vital to the functioning of this process.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gkk8u1tguspd9q2l9odst3225s","2014-01-14 14:18:48",NULL
"2046","2","Extremal Eigenvalue Problems in Optics, Geometry, and Data Analysis","2014-01-22 16:00:00","2014-01-22 17:00:00","SAS 4201","Braxton Osting","http://www.math.ucla.edu/~braxton/","University of California, Los Angeles",,,"Since Lord Rayleigh conjectured that the disk should minimize the first eigenvalue of the Laplace-Dirichlet operator among all shapes of equal area more than a century ago, extremal eigenvalue problems have been an active research topic. In this talk, Ill demonstrate how extremal eigenvalue problems arise in a variety of contexts, including optics, geometry, and data analysis, and present some recent analytical and computational results in these areas. One of the results Ill discuss is a new graph partitioning method where the optimality criterion is given by the sum of the Dirichlet energies of the partition components. With intuition gained from an analogous continuous problem, we introduce a rearrangement algorithm, which we show to converge in a finite number of iterations to a local minimum of a relaxed objective function. The method compares well to state-of-the-art approaches when applied to clustering problems on graphs constructed from synthetic data, MNIST handwritten digits, and manifold discretizations.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/simb7lpnijuc0sfikfuij4r9ac","2014-01-14 14:20:44","2014-01-14 16:37:26"
"2049","2","Real Algebraic Geometry from the Random Viewpoint","2014-01-27 16:00:00","2014-01-27 17:00:00","SAS 4201","Erik Lundberg","http://www.math.purdue.edu/~elundber/","Purdue University",,,"How many zeros of a random polynomial are real?  M. Kac (1943) answered this question for a Gaussian ensemble of polynomials.  The real section of the zero set of a polynomial in several variables is more complicated, but Kacs methods can be used to study metric properties, such as the total volume of a random real algebraic hypersurface (in projective space).  The study of topological properties such as the number of connected components (a random version of Hilberts sixteenth problem) requires additional techniques.  I will discuss some breakthroughs in this direction.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h2dc7r9vqr0edt5n38f1hrn484","2014-01-14 14:22:01","2014-01-14 16:37:58"
"2052","2","PDE Method for Analyzing Unorganized Data in 3D and Higher","2014-01-31 16:00:00","2014-01-31 17:00:00","SAS 4201","Rongjie Lai","http://www.math.uci.edu/~rongjiel/Home.html","University of California, Irvine",,,"Point clouds are the simplest and most basic forms for data representation in 3D and higher. Examples include those used in 3D modeling, image science, the Internet and many others. Analyzing and inferring the underlying structure from the point clouds are crucial in many applications. However, 
these raw data or primitive representations in Rn are lack of global parameterization and far from intrinsic, which obstruct further intrinsic and global analysis for given data. On the other hand, point clouds from practical problems are usually with certain coherent structures which allow us to model them as points sampled from lower dimensional Riemmannian manifolds in a high dimensional space. In this talk, I will discuss our work on solving geometric partial differential equations (PDEs) on point clouds. This method can achieve high order accuracy and enjoy more flexibility. It can be applied to manifolds with arbitrary dimensions and co-dimensions. This approach enables us to propose geometric methods for analyzing and understanding point clouds through solutions of PDEs on point clouds. Our methods can be widely used in intrinsic geometric quantities extraction, comparison, registration and recognition/classification for point clouds. Meanwhile, I will also demonstrate several applications in brain image analysis, data science as well as extreme spectrum problems in Riemmannian geometry using our computation tools.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jq0ddms9ldnufrk2nd7ges6ugk","2014-01-14 14:31:40","2014-01-28 11:10:39"
"2055","2","Matrix integrals and combinatorics: from maps to monotone Hurwitz numbers","2014-02-05 16:00:00","2014-02-05 17:00:00","SAS 4201","Jonathan Novak","http://math.mit.edu/~jnovak/h.home.html","Massachusetts Institute of Technology","Agnes Szanto",,"In this lecture Ill begin by motivating and describing the surprising connection between random matrices and the enumeration of maps on surfaces discovered by physicists some twenty years ago.  Ill then explain how the quest to extend this connection to several interacting random matrices leads to the asymptotic analysis of a remarkable special function known as the 
Harish-Chandra-Itzykson-Zuber integral.  Quite surprisingly, the HCIZ integral turns out to be closely related to a desymmetrized version of the problem of counting branched covers of the Riemann sphere with given ramification data over two points and simple branching elsewhere.  This leads to a beautiful new set of combinatorial problems, some of which have been solved, thus leading to a better asymptotic understanding of the HCIZ integral.  Since the HCIZ integral turns out to be a Schur function in disguise, these results also have applications in asymptotic representation theory, and if time permits I will explain this as well.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ot1he2d9708q2dlg95snhliumc","2014-01-14 14:35:40","2014-02-03 15:44:54"
"2058","2","Determinants, Hyperbolicity, and Interlacing","2014-02-03 16:00:00","2014-02-03 17:00:00","SAS 4201","Cynthia Vinzant","http://www-personal.umich.edu/~vinzant/","University of Michigan, Ann Arbor","Jon Haunstein",,"Writing a multivariate polynomial as the determinant of a matrix of linear forms is a classical problem in algebraic geometry and complexity theory. Requiring that this matrix is Hermitian and positive definite at some point puts topological and algebraic restrictions on the polynomials that appear as the determinant and its minors. In particular the real zero sets of these polynomials are hyperbolic (or real stable) and interlace.  Ill talk about the beautiful geometry behind these determinants and its connection to optimization and combinatorics.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/57vakc5a03hg0t98n0lp7oqjrc","2014-01-14 14:36:46","2014-01-15 10:34:32"
"2064","3","Primary components of codimension two lattice basis ideals","2014-02-17 15:00:00","2014-02-17 16:00:00","SAS 4201","Zekiye Sahin",,"Texas A&M University",,,"We provide explicit combinatorial descriptions of the primary components of codimension two lattice basis ideals. The components of these binomial ideals  can be computed via adding certain monomials and using saturation. This is joint work with Laura F. Matusevich.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2uccn0si9j4rt8rutp4jf73hgo","2014-01-14 14:50:54","2014-02-17 10:37:58"
"2067","14","Departmental Tea and Cookies","2014-02-05 15:30:00","2014-02-05 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2r9nd1omkf8mospke6jukdivhg","2014-01-14 14:51:14",NULL
"2072","4","Stability Analysis of Rings for 2nd Order Models in Swarming","2014-03-19 15:00:00","2014-03-19 16:00:00","SAS 4201","Daniel Balague","http://dbalague.blogspot.com/","NC State Mathematics",,,"In this work we consider second order models in swarming in which individuals interact pairwise with a power-law repulsive-attractive potential. We study the stability for flock and mill ring solutions and we show how the stability of these solutions is related to the stability of a first order model. In unstable situations it is also possible to observe formation of clusters and fat rings.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/nj004a8n2esvfoiv02qndljf64","2014-01-15 06:43:18","2014-01-15 11:47:18"
"2075","4","Effects of emotion in swarming dynamics","2014-03-26 15:00:00","2014-03-26 16:00:00","SAS 4201","Jesus Rosado","http://www.math.ucla.edu/~jrosado/","UCLA","Daniel Balague",,"We will extend classic swarming models to describe the
influence of emotional contagion between the individuals of the group.  Well study them at three different scales: microscopic, kinetic and macroscopic, and see how the study of the continuum limit helps us understand key features of the model.","mahoefer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vhitkq3jchbqbl50kfq2k1840c","2014-01-15 06:44:40","2014-01-16 08:48:51"
"2078","4","The shape derivative of boundary value problems","2014-04-16 15:00:00","2014-04-16 16:00:00","SAS 4201","Matthias Eller","http://explore.georgetown.edu/people/mme4/?PageTemplateID=130","Georgetown University","Lorena Bociu",,"In the context of shape optimization the shape derivative is of fundamental importance. If the region in space or space-time underlying the boundary value problem (BVP) is allowed to vary in direction of a given vector field, one can compute the derivative of the solution to the BVP in direction of this vector field. The shape derivative for a wide class of BVPs for linear partial differential equations can be characterized as a solution of another BVP with a non-traditional boundary condition. Scalar equations and systems of equations will be considered and issues of regularity will be discussed.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sokv669t2rcgeed1jb4fukei4o","2014-01-15 11:24:40","2014-04-14 13:17:38"
"2082","2","Decay properties of matrix functions with application to ON methods in electronic structure computations","2014-02-24 16:00:00","2014-02-24 16:50:00","SAS 1102","Michele Benzi","http://www.mathcs.emory.edu/~benzi/","Emory ","Tim Kelley  Leroy Martin Chair Hiring Committee",,"Many problems in science and engineering involve
computations with large and sparse matrices.
In particular, some of the most challenging
computational problems in fields like solid
state physics and quantum chemistry involve the
approximation of functions of large, sparse
Hermitian matrices (Hamiltonians&quot), such
as the matrix exponential, the matrix square
root, the Fermi-Dirac function, and others.

Although the efficient evaluation of such matrix
functions presents considerable challenges,
optimal numerical methods that scale linearly
in the size N of the problem have become available
in recent years. The possibility of developing
such O(N) methods rests on the observation that
in many cases the entries in functions of
sparse matrices exhibit very rapid decay,
with only O(N) entries being non-negligible.

In this talk I will present a general theory
of decay for matrix functions, including rigorous
bounds for analytic functions of sparse matrices.
Our theory provides a rigorous proof of exponential
localization for the entries of the density matrix
for gapped systems in the framework of Density
Functional Theory for electronic structure
computations.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qdom639i33ue3kkpbop8qta4io","2014-01-18 08:31:07","2014-01-21 10:23:15"
"2084","22","Diagrammatic Calculus","2014-01-22 16:00:00","2014-01-22 16:50:00","SAS 2102","Radmila Sazdanovic",,"NC State",,"http://www.math.ncsu.edu/sumseries/spring2014/012214.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/r8equga415fbdsq87s38t2tpck","2014-01-21 08:56:41",NULL
"2086","22","Rectangulations and Pattern-avoiding permutations","2014-01-29 16:00:00","2014-01-29 16:50:00","SAS 2102","Nathan Reading",,"NC State",,"http://www.math.ncsu.edu/sumseries/spring2014/012914.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uituijcavr6nr28nchlvb9n7h4","2014-01-21 08:57:58",NULL
"2088","22","Rectangulations and Pattern-avoiding permutations","2014-02-05 16:00:00","2014-02-05 16:50:00","SAS 2102","Nathan Reading",,"NC State",,"http://www.math.ncsu.edu/sumseries/spring2014/020514.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/peq3fe7tebbq7dp72hh05tadu8","2014-01-21 08:59:08","2014-02-03 07:54:04"
"2090","6","Numerical Linear Algebra Methods in Data Mining","2014-01-31 13:00:00","2014-01-31 14:00:00","Room 1230 Engineering Bldg II","Yousef Saad","http://www-users.cs.umn.edu/~saad/","Minnesota","CS Dept",,"The field of  data mining is the source of  many new, interesting, and
sometimes challenging, linear algebra  problems.  In fact, one can say
that data  mining and  machine learning are  now beginning to shape a
&quotnew  chapter&quot in  numerical linear  algebra,  replacing Computational
Fluid  Dynamics and PDEs  as the  main source  of model problems in
Numerical Linear Algebra.  The talk will start with an overview of the
key concepts and then discuss dimension reduction methods which play a
major role. We will illustrate these concepts with a few applications,
including   information  retrieval,   face   recognition  and matrix
completion for recommender  systems. An important emerging application
is  materials  informatics.   The synergy  between high-performance
computing, efficient electronic structure algorithms, and data mining,
may  potentially lead  to  major discoveries  in  materials.  We will
report  on  our  first   experiments  in  materials informatics,  a
methodology which blends data mining and materials science.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5i92rosa5dokopojnna778t5no","2014-01-21 12:45:38",NULL
"2092","3","Betti diagrams from graphs","2014-02-24 14:30:00","2014-02-24 15:30:00","SAS 4201","Matthew Stamps","http://www.math.kth.se/~stamps/","Royal Institute of Technology KTH",,,"The emergence of Boij-S\&quot;oderberg theory has given rise to new connections between combinatorics and commutative algebra.  Herzog, Sharifan, and Varbaro showed that every Betti diagram of an ideal with a $k$-linear minimal resolution arises from that of the Stanley-Reisner ideal of a simplicial complex.  In this talk, I will extend their result for the special case of $2$-linear resolutions using purely combinatorial methods.  Specifically, I will give bijections between Betti diagrams of ideals with $2$-linear resolutions, threshold graphs, and anti-lecture hall compositions.  I will also show that any Betti diagram of a \emph{module} with a $2$-linear resolution can be realized by that of a direct sum of Stanley-Reisner rings associated to threshold graphs.  The key observation is that these objects all correspond to the lattice points of a normal reflexive lattice polytope.  This is joint work with Alex Engstr\&quot;om.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ja7lnt82ekqem3rvvfals13ad4","2014-01-22 10:01:43","2014-02-19 10:02:48"
"2094","19","Organizational Meeting","2014-01-29 15:00:00","2014-01-29 16:00:00","SAS 1108","Organizational Meeting",,,,,,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kscksl5gtce48obt0t857vjsj0","2014-01-22 12:20:52","2014-01-24 14:56:01"
"2096","2","Mathematical Models of Biological Markers","2014-01-22 14:30:00","2014-01-22 15:30:00","Cox 306","Chris Remien",,"NIMBios","H.T. Banks",,"Indirect measurements are ubiquitous in the life sciences because it is often impossible or impractical to directly measure the process of interest. I will show how dynamic mathematical models of biological systems can aid interpretation of biological markers, focusing on the dynamics of acetaminophen (APAP, Tylenol) overdose, stable isotope signatures, and metabolism of toxins by gut microbes. APAP is one of the most common drugs on the planet. While safe in therapeutic doses, APAP is the leading cause of acute liver failure in the developed world. I will present a mathematical model of APAP overdose that can be used to estimate time since overdose, overdose amount, and need for liver transplant from measurable markers of liver injury at the time of hospital admission. Similarly, stable isotopes are used by ecologists and forensic scientists as markers of diet and movement patterns. I will show how, with suitable mathematical models, stable isotope ratios of the hair of a murder victim were used to reconstruct the victims movement history in the time preceding death. Finally, I will introduce a new project that involves modeling the contribution of gut microbes to the metabolism of toxins in mammalian diets, focusing on oxalate, a common plant secondary compound and a primary constituent of kidney stones, as a model toxin.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/311l6ao9stoe4kjdja651t04io","2014-01-22 13:18:43",NULL
"2098","2","The Essential Role of Phase Delayed Inhibition in Decoding Synchronized Oscillations within the Brain","2014-01-24 14:30:00","2014-01-24 15:30:00","Cox 306","Mainak Patel","http://fds.duke.edu/db/aas/math/mainak","Duke University","H.T. Banks",,"The widespread presence of synchronized neuronal oscillations within the brain suggests that a mechanism must exist that is capable of decoding such activity.  Two realistic designs for such a decoder include: 1) a read-out neuron with a high spike threshold, or 2) a phase-delayed inhibition network motif. Despite requiring a more elaborate network architecture, phase-delayed inhibition has been observed in multiple systems, suggesting that it may provide inherent advantages over simply imposing a high spike threshold. We use a computational and mathematical approach to investigate the efficacy of the phase-delayed inhibition motif in detecting synchronized oscillations, showing that phase-delayed inhibition is capable of detecting synchrony far more robustly than a high spike threshold detector. Furthermore, we show that in a system with noisy encoders where stimuli are encoded through synchrony, phase-delayed inhibition enables the creation of a decoder that can respond both reliably and specifically to a stimulus, while a high spike threshold does not.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g1981ifnsmk2s302o6t6qe9lv4","2014-01-22 13:22:30",NULL
"2100","2","Modeling the Dynamics of Tumor Heterogeneity","2014-01-27 14:30:00","2014-01-27 15:30:00","Cox 306","Ruchira Datta","http://math.berkeley.edu/~datta/","Cancer Research Institute, UCSF","H.T. Banks",,"Simon Tavar introduced Approximate Bayesian Computation (ABC) for simulating posterior distributions where computing the likelihood is intractable. In 2010, Tavar and Andrea Sottoriva extended ABC to complex models from cancer biology.  On the other hand, Hisashi Ohtsuki, Martin Nowak and colleagues have introduced evolutionary graph theory, the study of evolutionary dynamics on graphs, and have proved results about time to fixation (i.e., for one subpopulation to take over the graph) in several settings. We will recapitulate these results and also characterize the nontrivial spatial distributions that arise and are observed during clinical timescales.  We will use measures of spatial/spatiotemporal statistics of point processes arising from a variety of fields as summary statistics for ABC, to see if we can use them to distinguish regimes of interest in the parameter space corresponding to different hypotheses (e.g., cooperation, competition, and neutral coexistence of different subpopulations occupying the graph). We will apply the resulting new statistical tests to images of heterogeneous tumors, informing the course of therapy. Time permitting, we will touch on the connection with our work on the theory of graphical games.  This research is in progress.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5sv2h1nghcn09am5dtmo6o16ak","2014-01-22 13:23:55","2014-01-22 13:27:58"
"2102","24","MGSA Pizza Party","2014-01-23 12:00:00","2014-01-23 14:00:00","SAS 4104",,,,,,"To start the Spring semester off with a bang (after all the JMM excitement, of course), we will be hosting a PIZZA PARTY  Thursday, Jan 23 from 12-2PM in the 4th floor math commons. Well be selling math department mugs for $5, water bottles for $2, and t-shirts (last years are $7, this years are $13).","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mqute1ne1n0opg70oohk1g4v0g","2014-01-23 11:32:59",NULL
"2104","8","Binomial Irreducible Decomposition","2014-02-25 16:30:00","2014-02-25 17:30:00","SAS 4201","Christopher ONeill","https://fds.duke.edu/db/aas/math/musicman","Duke","Elizabeth Gross",,"A recent paper by Kahle and Miller introduces a combinatorial framework for constructing primary decompositions of binomial ideals.  In this talk, we extend this framework to construct irreducible decompositions of binomial ideals, and answer a longstanding conjecture from Eisenbud and Sturmfels.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3pp0pkq763aemm4fsokcq1mlcc","2014-01-27 09:28:37","2014-02-19 21:07:43"
"2106","8","Homotopy Methods for Pattern Recognition in High-Dimensional Data Sets","2014-04-08 16:30:00","2014-04-08 17:30:00","SAS 4201","Brent Davis","http://www.math.colostate.edu/~davisb/","Colorado State","Elizabeth Gross",,"This talk will introduce a new computational tool to analyze clusters of points embedded on a union of Grassmann manifolds, called the MLV line of  best fit. One feature of the MLV line is the ability to capture features common line is the solution to an optimization problem involving principal angles between subspaces. It will be shown that the global solution can be obtained from the multivariate eigenvalue problem which has connections to multi-set canonical correlation analysis.  Two computational methods will be discussed: Homotopy methods using numerical algebraic geometry and the alternating variable method.  This is joint work with Dan Bates, Michael Kirby, Justin Marks, and Chris Peterson.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3293gsp2v2ausauimct4c2i9ok","2014-01-27 09:31:07","2014-04-03 13:30:00"
"2108","8","Semi-algebraic geometry of common lines","2014-04-15 16:30:00","2014-04-15 17:30:00","SAS 4201","David Dynerman","http://www.math.wisc.edu/~dynerman/","Wisconsin","Elizabeth Gross",,"Cryo-electron microscopy (cryo-EM) is a technique for discovering the 3D structures of small molecules. To perform this 3D reconstruction a large number of 2D images taken from unknown microscope positions must be correctly positioned back in 3D space. Although these microscope positions are unknown, the common lines of intersection of the image planes can be detected and used in 3D reconstruction. A major difficulty in this process is large amounts of noise in the common line data.

The set of all noiseless common lines forms a semi-algebraic set (a set defined by polynomial equalities and inequalities). We define and describe the geometry of this set, and briefly discuss applications.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/4mkl17ntu4d28v0lo7fjruevmk","2014-01-27 09:32:23","2014-04-10 20:45:40"
"2110","2","Randomized Block Coordinate Gradient Methods for a Class  of Structured Nonlinear Programming","2014-02-04 16:00:00","2014-02-04 17:00:00","SAS 4201","Zhaosong Lu",,"Simon Fraser University",,,"Nowadays a class of huge-scale structured optimization problems arise in some emerging areas such as machine learning. They can be reformulated as minimizing the sum of a smooth and block separable nonsmooth functions.  For these problems, it is prohibitive to evaluate the full gradient of the smooth component of the objective function due to huge dimensionality and hence the usual gradient methods cannot be efficiently applied. Nevertheless, its partial gradients can often be computed much more cheaply. In this talk we study a randomized block coordinate gradient (RBCG) method for solving this class of problems. At each iteration this method randomly picks a block, and solves a proximal gradient subproblem over the subspace defined by the block that only uses a partial gradient and usually has a closed-form solution.  We present new iteration complexity results for this method when applied to convex problems. We also propose a nonmonotone RBCG method for solving a class of nonconvex problems with the above structure, and establish their global convergence and iteration complexity. In addition, we present new complexity results for the accelerated RBCG method proposed by Nesterov for solving unconstrained convex optimization problems. Finally, we discuss the application of these methods for solving some support vector machine problems and report some computational results. (This is a joint work with Lin Xiao at Microsoft Research Redmond.)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ql17ik0el6ombjeaaqs4oeu41o","2014-01-27 10:06:53","2014-02-03 09:54:02"
"2112","2","Computing moment-matching cubature formulas using optimization techniques, with applications in stochastic and robust optimization","2014-02-20 14:30:00","2014-02-20 15:30:00","SAS 4201","David Papp",,"Harvard Medical School","Campbell",,"Stochastic optimization problems are the most
popular models for decision making under uncertainty. They translate
to finding the optimal value of a function that is expressible as an
integral of some given function. These integrands are often
high-dimensional, and sometimes expensive to compute however, they
often have a sparse structure, convexity in the optimization
variables, or other special characteristics that may be exploited by
numerical methods. The traditional cubature formulas, which use a
large number of points and are aimed at matching all moments of the
underlying measure up to a certain degree, are insufficient to
approximate these integrals. We propose a flexible method based on
convex optimization that can generate cubature formulas that  match
any prescribed set of moments, and thereby exploit the special
properties of the integrand. The method is compared to Monte Carlo and
quasi-Monte Carlo (rank-one lattice) methods on both integration and
stochastic optimization problems.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7ibnkhre43stfomp8qne6uvrf4","2014-01-27 10:08:33","2014-02-17 10:25:45"
"2114","2","Optimization models for cancer treatment using arc therapy","2014-02-14 11:30:00","2014-02-14 12:30:00","Daniels 434","David Papp",,"Harvard Medical School",,,"During radiotherapy, cancer patients are irradiated
with beams of ionizing radiation that kill both cancerous and healthy
cells. Treatment, therefore, has to be carefully designed in order to
deliver the prescribed radiation dose to the tumor while sparing
critical organs and healthy tissue from damage. Recently, radiotherapy
delivery using arc therapy has been gaining popularity in clinics,
since it has the potential to improve treatment plan quality while
shortening treatment time. During this type of therapy, patients can
be irradiated from virtually every angle, with a beam whose shape is
continuously changing as the radiation source revolves around the
patient. Optimizing such a treatment is much more challenging than
designing conventional treatments, because natural formulations of
this problem are both large-scale and non-convex optimization models.
As a result, currently there is little support of this modality in
treatment planning software, and the solutions are based on rather
weak heuristics. The talk will present a novel optimization model that
can be solved approximately using convex optimization methods, and can
also be used in multi-criteria treatment planning. Computational
results show that the approach provides high quality treatment plans
for a variety of cancer types.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/onl3l8uppk487utb89lin749dk","2014-01-27 11:01:13","2014-01-27 11:01:39"
"2116","2","Optimization: Dealing with Uncertainty","2014-02-06 16:00:00","2014-02-06 17:00:00","SAS 4201","Karthik Chandrasekaran","http://people.seas.harvard.edu/~karthe/","Harvard University",,,"Optimization problems are ubiquitous in contemporary engineering. A principal barrier to solving several real-world optimization problems is input uncertainty. In this talk, I will present new tools to study probabilistic instances of integer programs. As an application I will show a phase-transition phenomenon in a simple distribution model for random integer programs.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/trla153t94l1sr3i2j9usc11kc","2014-01-28 10:19:59","2014-02-05 12:39:55"
"2118","19","Journal Club","2014-02-05 15:00:00","2014-02-05 15:00:00","SAS 1108","Journal Club",,,,,"We will discuss the paper by Anders Bjorner and Michelle Wachs, &quotOn lexicographically shellable posets,&quot Transactions of the AMS, Volume 277, Number 1, May 1983, pp. 323-341.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2bt07evv5rrou06b1oerp0c2gg","2014-01-29 11:11:53","2014-01-29 11:13:10"
"2122","2","Convex relaxations for sensor network localization","2014-02-11 16:00:00","2014-02-11 17:00:00","SAS 4201","Ting Kei Pong",,"PIMS postdoctoral fellow at University of British Columbia",,,"Convex optimization techniques have been applied to hard
nonconvex optimization problems to obtain approximate solutions. In this
talk, we focus on the sensor network localization problem, which is the
problem of determining the location of points given some anchor nodes
(with known position) and distance estimates between some pairs of points.
This problem is NP-hard in general, and is closely related to graph
realization and molecular conformation problems. We compare the strength
of several convex relaxations for this problem, and present conditions
under which the convex relaxations return the true sensor positions.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l1sjue1j1ajg5rq69se9fpvkp0","2014-01-29 14:33:57","2014-02-04 09:43:06"
"2124","14","Departmental Tea and Cookies","2014-02-11 15:30:00","2014-02-11 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/f28pk9cbbeb6q1fp52ma44iq2o","2014-01-29 14:35:58","2014-01-30 12:04:11"
"2127","3","Bernoulli type games and enumeration by kernel positions","2014-02-21 14:00:00","2014-02-21 15:00:00","SAS 4201","Gabor Hetyei","http://math2.uncc.edu/~ghetyei/","UNC Charlotte",,,"We introduce a class of two-player games on posets with a rank function,
in which each move of the winning strategy is unique. This allows to
enumerate the kernel positions by rank. Our main example is a simple
game in which the number of kernel positions of rank n is a signed
factorial multiple of the nth Bernoulli number of the second kind. A
generalization of this game  provides a combinatorial model for the
degenerate Bernoulli numbers introduced by Carlitz. Using numerical
integration formulas involving the Bernoulli games of the second kind,
we show how to construct a scoring system such that the expected gain of
a player becomes the integral of a given function on [0,1]. Finally, 
in the special case when our game is a certain truncation game on words,
we find an explicit description of the winning strategy, implying 
closed-form formulas for the number of kernel positions. Thus  we obtain
new formulas for Bernoulli numbers and polynomials of the second kind
and a new combinatorial model for the numbers counting the connected
permutations. For connected permutations, the decomposition used to find
the winning strategy is bijectively equivalent to Kings decomposition,
used to recursively generate a transposition Gray code of the connected
permutations.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gqr35539hiilmggle9afn8jhrs","2014-02-02 20:23:14","2014-02-13 10:58:45"
"2130","3","Product formulas for the volumes of flow polytopes","2014-02-28 15:00:00","2014-02-28 16:00:00","SAS 1102","Karola Meszaros","http://www.math.cornell.edu/~karola/","Cornell University",,,"I will present product formulas for the volumes of a special class of flow polytopes. This class is inspired by the Chan-Robins-Yuen polytope, whose volume is equal to a product of Catalan numbers (although there is no known combinatorial proof of this fact!). I will explain how certain algebras defined by Kirillov encode subdivisions of flow polytopes. Finally, I will show how to derive identities involving the Kostant partition function, using a connection with flow polytopes discovered by Postnikov and Stanley.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h21lbio4rhrm8vpcb09ka75cuo","2014-02-02 20:27:40","2014-02-17 10:57:21"
"2135","21","Kwangil Koh Lecture on Mathematics in Our Time","2014-04-14 16:30:00","2014-04-14 17:30:00","SAS 2203","Iain D. Couzin","http://icouzin.princeton.edu/","Princeton University",,"http://www.math.ncsu.edu/events/Couzin.php","From Democratic Consensus to Cannibalistic Hordes: The Principles of Collective Behavior

A fundamental problem in a wide range of biological disciplines is understanding how  complexity at a macroscopic scale results from the actions and interactions among the individual components. Animal groups such as bird flocks, fish schools and insect swarms frequently exhibit complex and coordinated collective behaviors and present unrivaled opportunities to link the behavior of individuals with the functioning and efficiency of dynamic group-level properties. Using an integrated experimental and theoretical approach, involving both insects and vertebrates (including humans), I will address both how, and why, animals coordinate behavior.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7ar5rs55jmgnm0n8k2ocqj1udo","2014-02-03 10:49:47","2014-02-03 10:51:42"
"2139","31","Real algebraic curve plotting through Bertini","2014-02-05 11:15:00","2014-02-05 12:15:00","SAS 4201","Daniel Brake",,"NC State",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/23aqh0jacn1agpu0qq7vdfteu0","2014-02-03 16:44:26",NULL
"2142","19","TBA","2014-02-12 15:00:00","2014-02-12 16:00:00","SAS 1108","Scott Batson",,"NCSU",,,,"redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/e5a37rmbpkgq1rqof8bmgv5n2c","2014-02-06 14:44:33",NULL
"2147","8","Noetherianity for infinite-dimensional toric ideals","2014-04-22 15:00:00","2014-04-22 16:00:00","SAS 4201","Robert Krone","http://people.math.gatech.edu/~rkrone3/","Georgia Tech","Seth Sullivant",,"Given a family of ideals which are symmetric under some group action on the variables, a natural question to ask is whether the generating set stabilizes up to symmetry as the number of variables tends to infinity. We answer this in the affirmative for a broad class of toric ideals, settling several open questions in work by Aschenbrenner-Hillar, Hillar-Sullivant, and Hillar-Martin del Campo. The proof is largely combinatorial, making use of matchings on bipartite graphs, and well-partial orders.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bsu026vvh6bil25i1d9agemiq8","2014-02-06 20:00:21","2014-04-02 14:25:35"
"2153","22","From Polynomials to 3D Printing: How to Print an Algebraic Surface","2014-02-19 16:00:00","2014-02-19 16:50:00","SAS 2102","Daniel Brake",,,,"http://www.math.ncsu.edu/sumseries/spring2014/021914.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i07c8em20c2ucuo2fld7m3e7ps","2014-02-07 12:21:00","2014-02-10 12:14:31"
"2156","22","Snowflakes, balloons, and the cardiovascular system","2014-02-26 16:00:00","2014-02-26 16:50:00","SAS 2102","Lorena Bociu","http://www4.ncsu.edu/~lvbociu/","NC State",,"http://www.math.ncsu.edu/sumseries/spring2014/022614.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/02d15eirk90v9kniljt28amjb4","2014-02-07 12:22:04","2014-02-12 09:25:21"
"2159","34","Early membrane evolution: Membrane metabolism and functions in  the last common ancestor of living organisms","2014-02-12 10:00:00","2014-02-12 11:15:00","SAS 4201","Jonathan Lombard","http://www.jonathan-lombard.net/","NESCent",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fp2c3o9knr82sc1tnf9qf0dl8o","2014-02-07 14:05:24",NULL
"2162","31","Radiative Transport Models","2014-02-05 11:15:00","2014-02-05 12:15:00","SAS 4201","Derya Sahin",,"UC Merced",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/9uebn2hj5c01f5488b6s5ucjao","2014-02-09 21:26:36",NULL
"2165","31","Radiative Transport Models","2014-02-12 11:15:00","2014-02-12 12:15:00","SAS 4201","Derya Sahin",,"UC Merced",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3cdras61ri1qhr5q9sql39gp7s","2014-02-09 21:29:39",NULL
"2171","19","TBA","2014-02-19 15:00:00","2014-02-19 16:00:00","SAS 1108","Scott Batson","http://www4.ncsu.edu/~spolste/","NC State",,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lsbeeaf69nlrvhqgorvtv03148","2014-02-11 10:17:28","2014-02-19 14:38:52"
"2174","4","Singularities of the Mean Curvature Flow","2014-04-09 15:00:00","2014-04-09 16:00:00","SAS 4201","Andrew Cooper","http://www4.ncsu.edu/~aacoope2/","NC State",,,"The mean curvature flow of submanifolds is the downward gradient flow for the area functional. Though it is gradient, the flow is nonlinear, so finite-time singularities are expected. In this talk well introduce some basics of the mean curvature flow and give a characterization of what goes wrong to cause the singularity, by using the interplay between two different rescaling analyses. Well also show some examples where these two singularity models can give enough information to allow singularity resolution.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cb4kksqn4epq18e7kr26v1id18","2014-02-12 09:42:37","2014-04-09 14:41:51"
"2180","8","The degree of the central curve in quadratic programming","2014-03-25 16:30:00","2014-03-25 17:30:00","SAS 4201","Serkan Hosten","http://math.sfsu.edu/serkan/","San Francisco State","Seth Sullivant",,"For convex optimization problems, such as linear, quadratic, or semidefinite programming, a class of interior point algorithms track the so-called central path to an optimal solution. The central curve, the Zariski closure of the central path, is an algebraic curve and it has been recently studied by De Loera, Sturmfels, and Vinzant in the linear case. In particular, the degree of the central curve for linear programming has been computed, and this has implications for the complexity of the interior point algorithms. We tackle the next case, the degree of the central curve for quadratic programming.  After a reduction to the &quot;diagonal&quot; case, we conjecture a formula and present a strong case for the conjecture.  This work in progress is joint with Dennis Schlief from SFSU and the talk will be  accessible even if your interest is not in optimization.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/247m2asqf0p77ku3reg5e78lts","2014-02-13 09:57:28","2014-03-18 14:55:11"
"2183","27","Solving Polynomial Equations","2014-10-13 08:00:00","2014-10-17 17:00:00","Simons Institute, Berkeley",,,,"Jon Hauenstein","http://simons.berkeley.edu/workshops/algebraicgeometry2014-2",,"jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tpc5kn9srnoba4il5c3mgh4fro","2014-02-13 10:00:29","2014-02-13 10:01:14"
"2186","19","Cones, Normal Semigroups and Contingency Tables","2014-03-05 15:00:00","2014-03-05 16:00:00","SAS 1108","Daniel Bernstein",,"NC State",,,"This talk will be about how algebraic and combinatorial methods may be used to solve an integer feasibility problem having to do with contingency tables.","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/13v792ctcqs2451f6vhlauoi0k","2014-02-14 12:11:40","2014-02-28 20:37:02"
"2187","2","Subalgebras of the Fomin-Kirillov algebra","2014-02-19 16:15:00","2014-02-19 17:15:00","SAS 4201","Ricky Ini Liu","http://www-personal.umich.edu/~riliu/","University of Michigan",,,"One of the main unsolved problems in Schubert calculus is to give a combinatorial formula for the structure constants in the cohomology of the flag variety. Fomin and Kirillov introduced a noncommutative quadratic algebra in which the existence of certain monomial expansions would yield a solution to this problem. I will discuss recent efforts towards understanding the structure of the Fomin-Kirillov algebra. In particular, I will describe certain subalgebras that are surprisingly well-behaved and have properties analogous to those of finite Coxeter groups, which suggests that they are worthy of independent interest. This is joint work with Jonah Blasiak and Karola Meszaros.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9ee7olfiqoip59nvpaqn7psmtg","2014-02-16 10:12:52",NULL
"2190","31","Radiative Transport Models","2014-02-19 11:15:00","2014-02-19 12:15:00","SAS 4201","Derya Sahin","http://campillos.ucmerced.edu/~dsahin/","University of California, Merced",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/43hste0kioe25t4n5mjr2e78us","2014-02-16 23:12:46",NULL
"2193","24","MGSA Cookie Contest","2014-02-18 12:00:00","2014-02-18 14:00:00","SAS 104",,,,,,"Just bring a cookie dish either to SAS 3213 or directly to the 4th floor lounge.
Be sure to include 
your name
recipe name
any ingredients commonly associated with allergies 
controversial ingredients, such as alcohol
If you dont feel like baking, no sweat! Stop on by to sample the delectable cookies your colleagues have made. We just ask you to rank your top 2 favorite cookies. 

Also, if you havent bought this years MGSA T-shirt, dont worry! You can buy one at the cookie contest event! They are $13 for sizes S-XL and $15 for size 2XL. They come in lime green or red! We take cash or check.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jf1i02gfjaqpknjs6u12un1kjs","2014-02-16 23:42:11",NULL
"2196","10","Towards Distributed Muti-agent Optimization in a Stochastic Derivative-free Setting","2014-02-17 14:00:00","2014-02-17 15:00:00","SAS 4201","Jeffrey Larson",,"Postdoc, Royal Institute of Technology",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/14bmbo9cnhm7qfmv6k56dt2f9s","2014-02-16 23:56:11",NULL
"2199","10","Heavy-duty Vehicle Platooning and Scheduling Swedish Handball","2014-02-18 11:00:00","2014-02-18 12:00:00","Daniels 371","Jeffrey Larson",,"Postdoc, Royal Institute of Technology",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ol63f920i54tlhleo8j1jpcdk0","2014-02-17 00:01:48",NULL
"2202","21","Triangle Lectures in Combinatorics","2014-02-22 09:15:00","2014-02-22 17:00:00","Sitterson Hall Room 014, University of North Carolina, Chapel Hill ",,,,,"http://www.math.ncsu.edu/TLC/","The Triangle Lectures in Combinatorics is a series of combinatorial workshops held each semester on a Saturday in the Research Triangle region of North Carolina, funded by the National Security Agency and the National Science Foundation.  The workshop this spring will be hosted by the University of North Carolina, Chapel Hill  in Chapel Hill, North Carolina on February 22, 2014.  It will include four one hour invited talks as well as coffee breaks and ample time for discussions throughout the day.  There will also be two related seminar talks on Friday afternoon just prior to the meeting.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p9smm1alfesl41n3sl213u28do","2014-02-17 09:53:39",NULL
"2205","34",,"2014-02-19 10:00:00","2014-02-19 11:15:00","SAS 4201","Eric Stone",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j5e5jja7h9rhour4jd89jcu1h4","2014-02-17 10:04:34",NULL
"2208","34","Early membrane evolution: Membrane metabolism and functions in  the last common ancestor of living organisms","2014-02-26 10:00:00","2014-02-26 11:15:00","SAS 4201","Jonathan Lombard","http://www.jonathan-lombard.net/","NESCent",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/iib72ck0ij5etpc55dm21qj9ao","2014-02-17 10:10:40",NULL
"2211","15","SIAM Meeting: Working at SAS","2014-02-28 12:30:00","2014-02-28 13:15:00","POE 224",,,,,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0ghkjicme13n5s13le780vb2ns","2014-02-17 10:17:56","2014-02-17 10:19:14"
"2214","14","Departmental Tea and Cookies","2014-02-19 15:30:00","2014-02-19 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/duq6qd8pab03eoocba3gav0c4g","2014-02-18 09:44:46",NULL
"2217","31","Dispersive shock waves and shallow ocean-wave line-soliton interactions","2014-02-26 11:15:00","2014-02-26 12:15:00","SAS 4201","Douglas Baldwin","http://www.douglasbaldwin.com/","University of Colorado at Boulder",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lmt5f6566v3d4ph560qg5s5a74","2014-02-23 22:47:17",NULL
"2220","9","Sequential Monte Carlo particle filtering for parameter estimation","2014-03-04 16:30:00","2014-03-04 17:30:00","Cox 306","Andrea Arnold",,"Case Western Reserve University","Alun Lloyd",,"Title: Sequential Monte Carlo particle filtering for parameter estimation

Abstract:

A central problem in numerous applications is the estimation of the unknown parameters of a system of differential equations from noisy measurements of some of the states at discrete times.  Formulating the parameter estimation problem in a Bayesian statistical framework, we derive a systematic method for defining the innovation term in the time evolution update of particle filter sequential Monte Carlo algorithms based on an estimate of the approximation errors in numerical propagation.  More precisely, we propose to carry out the time integration in the evolution step using linear multistep method (LMM) numerical solvers.  The choice of LMMs in this context is motivated by the fact that their stability properties are well-known, and good estimates for the accumulating discretization error exist, thereby providing a basis for estimating rigorously the innovation variance.  We demonstrate the effectiveness of the resulting algorithm on a test problem with some of the characteristics of the dynamical systems encountered in metabolic models, as well as an application to dynamic PET scan data.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/812l1qed6pb2nlq93d71aifisg","2014-02-24 07:37:22","2014-03-02 07:51:54"
"2223","31","Interpolation and Smolyaks Algorithm","2014-03-05 11:15:00","2014-03-05 12:15:00","SAS 4201","James Nance",,"NC State",,,"In this talk I will review the basics of one dimensional polynomial interpolation and then discuss multidimensional polynomial interpolation using Smolyaks algorithm and sparse grids. Full grids suffer from the curse of dimensionality where the number of nodes grows exponentially with dimension, but sparse grids improve the ratio of invested storage to approximation accuracy and help alleviate this curse. Smolyaks algorithm is a general approach that uses optimal approximations from the d=1 case to yield an almost optimal approximation for d&gt;1 dimensions. This talk will include demos and, if time allows, a discussion of an application to Quantum Chemistry.","ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/f7kbrkd627tuaurvnio6n9j1go","2014-02-24 11:26:28","2014-02-26 14:04:03"
"2226","31","Stability Analysis of Rings for 2nd Order Models in Swarming","2014-03-19 11:15:00","2014-03-19 12:15:00","SAS 4201","Daniel Balague","http://dbalague.blogspot.com/","NC State",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/fn52dsnv8qep0mp3sc8vemc0hk","2014-02-24 11:32:27","2014-03-17 11:03:13"
"2229","22","Releasing your Inner Polynomial","2014-03-05 16:00:00","2014-03-05 16:50:00","SAS 2102","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,"http://www.math.ncsu.edu/sumseries/spring2014/030514.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0shvpl6t05ga0881jrin2rqmg8","2014-02-24 13:42:34",NULL
"2232","14","Mathematics Awards Day","2014-04-21 16:00:00","2014-04-21 17:00:00","SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rl4uaqeh8odrtjbq6501s05srg","2014-02-25 14:34:43","2014-03-31 16:02:27"
"2235","14","Awards Day Reception","2014-04-21 15:30:00","2014-04-21 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/32q47a791upnclj5hls8calvm0","2014-02-25 14:35:49","2014-03-31 16:03:31"
"2238","19","Journal Club","2014-04-09 15:00:00","2014-04-09 16:00:00","SAS 1108","Shira Polster","http://www4.ncsu.edu/~spolste/","NC State",,,"Shira Polster will lead a discussion of the paper, &quot;Tiling with Polyominoes and Combinatorial Group Theory&quot; by John Conway and J.C. Lagarias, Journal of Combinatorial Theory, Series A, Volume 53, Issue 2, March 1990, Pages 183208","redavids","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/99oonelklbrotscmad7eqv3ebo","2014-02-28 08:47:05",NULL
"2241","3","DJKM algebras and non-classical orthogonal polynomials","2014-03-03 14:10:00","2014-03-03 15:00:00","SAS 4201","Ben Cox","http://coxbl.people.cofc.edu/","College of Charleston",,,"We describe families of polynomials arising in the study of the universal central extensions of Lie algebras introduced by Date, Jimbo, Kashiwara, and Miwa in 1983, in their work on solutions to the Landau-Lifshitz equations. Two of the families of polynomials we show satisfy certain forth order linear differential equations, are orthogonal and are not of classical type.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o9srck3hp86sk1th3e6eelpafs","2014-02-28 15:04:04","2014-03-03 11:31:53"
"2244","28","AWM Weekly Ladies Lunch","2014-03-05 12:30:00","2014-03-05 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bd2ettgf3799idikk2mo051ufs","2014-03-03 11:28:21",NULL
"2247","34","An attempt to model the probability of a protein-coding DNA sequence given the protein structure","2014-03-05 10:00:00","2014-03-05 11:15:00","SAS 4201","Jeff Thorne and Kuangyu Wang",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5q4ttt8h03omo9onrifij55iec","2014-03-04 10:50:38",NULL
"2250","34","Reconstructing phylogenetic trees without alignments","2014-03-26 10:00:00","2014-03-26 11:15:00","SAS 4201","Seth Sullivant",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/rc8ts59plt09ems7leuaeuvrjs","2014-03-04 10:52:41",NULL
"2253","8","A Study In Multistability, and Criticality of Real Algebraic Sets","2014-04-01 16:30:00","2014-04-01 17:30:00","SAS 4201","Daniel Brake","http://www.math.ncsu.edu/~dabrake","NC State","Jon Hauenstein",,"Computational tools continue to gain dominance in many fields, including the biological sciences.  In biology, some researchers hunt for bistable systems, perhaps for novel switches.  The first portion of this talk will discuss the application of Paramotopy, a piece of numerical algebraic geometric software leveraging Bertini, to characterize multistability in 2-site enzymatic phosphorylation.  This is joint work with Dan Bates, Jeremy Gunawardena, Chris Nam, and Benjamin Gori.

The second part of this talk will look at methods for finding the real embedded part of a complex component of an algebraic variety.  Particularly, I have implemented a cellular decomposition method interfacing heavily with Bertinis homotopy tracker, for decomposing both curves and surfaces.  My main focus here will be on the computation of the critical sets, this being the most critical of the steps of the program.  This ongoing work is joint with Jon Hauenstein, Dan Bates, Charles Wampler, Wenrui Hao, and Andrew Sommese.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eg9e83io4g4r3aaetnv9ehn3sk","2014-03-07 14:44:09","2014-03-29 13:37:32"
"2254","15","SIAM Meeting","2014-03-31 12:20:00","2014-03-31 13:15:00","Riddick 315","Nick Trefethen","https://people.maths.ox.ac.uk/trefethen/","Oxford",,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/37m464s32nhmdr7ujkpkks7luk","2014-03-16 10:54:53",NULL
"2257","14","Departmental Tea and Cookies","2014-03-19 15:30:00","2014-03-19 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dlefo2c29f7usfvrcub39qlibg","2014-03-17 11:14:50","2014-03-18 12:02:11"
"2260","24","Dessert pi e","2014-03-18 12:00:00","2014-03-18 14:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s51a2crhn2i1aa54ijj3niia3c","2014-03-17 11:17:59",NULL
"2263","22","Uncertainty quantification","2014-04-09 16:00:00","2014-04-09 16:50:00","SAS 2102","Ralph Smith","http://www4.ncsu.edu/~rsmith/","NC State",,,"The quantification of uncertainties inherent to models, parameters, and experiments is critical to access the accuracy of predictions.  In this presentation, we will discuss basic issues that must be addressed when quantifying uncertainties inherent to physical and biological models.  This will be motivated by examples drawn from nuclear power plant design, HIV models, climate models, and the flying micro-robot Robobee.  Uncertainty quantification is naturally addressed in a Bayesian framework and we will use examples to motivate recent Metropolis and propagation algorithms, which are appropriate for large scale simulation models.  Finally, we will discuss the use of sensitivity analysis to isolate influential model inputs.  This is a new and evolving topic and open questions will be noted throughout the presentation.","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/6v5q8gql7o8cue661tjl8u8ei0","2014-03-17 11:31:47","2014-04-02 08:52:05"
"2266","22","Undergraduate Research Presentations","2014-04-23 16:00:00","2014-04-23 16:50:00","SAS 2102","Undergrad researchers",,"NC State",,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/i82sec9ole5r5fcvr4tml7n6eg","2014-03-17 11:32:56",NULL
"2269","28","AWM Weekly Ladies Lunch","2014-03-19 12:30:00","2014-03-19 13:30:00","Undergrad Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/m0kgmiao17i6ngmn51glq9t03g","2014-03-17 11:34:51",NULL
"2272","9","Feedback-Mediated Dynamics in the Kidney: Mathematical Modeling","2014-03-27 16:30:00","2014-03-27 17:30:00","Cox 306","Hwayeon Ryu",,"Duke University",,,"Feedback-Mediated Dynamics in the Kidney: Mathematical Modeling

Hwayeon Ryu
Department of Mathematics, Duke University

The glomerular filtration rate in the kidney is controlled, in part, by the tubuloglomerular feedback (TGF) system, which is a negative feedback loop that mediates oscillations in tubular fluid flow and in fluid NaCl concentration of the loop of Henle. In this study, we developed a mathematical model of the TGF system that represents NaCl transport along a short loop of Henle with compliant walls. A bifurcation analysis of the TGF model equations was performed by computing parameter boundaries, as functions of TGF gain and delay, that separate differing model behaviors. A comparison with a previous model, which represents only the TAL explicitly and other segments using phenomenological relations, indicates that explicit representation of the proximal tubule and descending limb of
the loop of Henle lowers the stability of the TGF system. Model simulations also suggest that the onset of limit-cycle oscillations (LCO) results in increases in the time-averaged distal NaCl delivery, whereas distal fluid delivery is not much affected.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v9ujj7lbl43qkj1tvgqsuh4neg","2014-03-18 23:14:54",NULL
"2275","26","Cell Proliferation Models, CFSE-Based Flow Cytometry Data, and Quantification of Uncertainty","2014-03-24 16:00:00","2014-03-24 17:00:00","SAS 4201","Dustin Kapraun",,"NC State",,"http://www4.ncsu.edu/~dfkaprau/cell_prolif/cell_prolif.html","The adaptive immune response is a major component of the human immune systems defense against invading pathogens. Since the success of the adaptive immune system depends on the capacity of lymphocytes to proliferate in response to various environmental stimuli (e.g., viral infection or organ transplant), the ability to make accurate predictions about lymphocyte behavior under specific conditions has important implications for immunology research. Such predictions can be made through the use of mathematical models.
In this talk, we provide an overview of our work using CFSE-based flow cytometry data in conjunction with cell proliferation models to estimate various biological quantities of interest. We first present a brief review of cell proliferation models that can be found in the literature and then describe the class of division- and label-structured PDE models which we have developed and used to analyze cell proliferation parameters. By examining a large data set involving replicated observations, we are able to analyze variability in CFSE-based flow cytometry data. Then, applying a statistical model and a generalized least squares parameter estimation scheme, we are able to analyze variability in parameter estimates across multiple donors and cell types. We conclude with a brief discussion of proposed improvements to our mathematical model and further uncertainty quantification work that is in progress.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2d73j1ns2jm3lmi8vhfs76pq80","2014-03-21 10:56:05",NULL
"2278","31","Hidden Boundary Smoothness for Some Classes of Linear Partial Differential Equations","2014-04-02 11:15:00","2014-04-02 12:15:00","SAS 4201","William Oakley",,"NC State",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dkb7350j3uci21rekv3sai4f80","2014-03-24 08:06:27",NULL
"2281","31","An Introduction to Discrete Nodal Domains and Applications to Networked Dynamic Systems","2014-04-23 11:15:00","2014-04-23 12:15:00","SAS 4201","Thomas Nudell",,"NC State",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ockvrevsq87k9qkubs76vrhbfs","2014-03-24 08:08:48","2014-04-22 22:36:33"
"2284","31","Keep it Fun: Fluid Dynamics in the Park","2014-04-30 11:15:00","2014-04-30 12:15:00","SAS 4201","Harrison Potter",,"Duke",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/k59a8g5gendrf7tu4j9rhb4mfc","2014-03-24 08:11:16","2014-04-29 09:24:55"
"2287","14","Departmental Tea and Cookies","2014-03-26 14:30:00","2014-03-26 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dd4dsst3rul1bjsctuh15a8dek","2014-03-24 09:39:29",NULL
"2290","34","Untangling Selection and Mutation in non-coding RNA","2014-04-16 10:00:00","2014-04-16 11:15:00","SAS 4201","Joshua Martin","http://www.nescent.org/science/awards_summary.php?id=344","NESCent",,,"Over 90% of the human genome is transcribed but never translated. These non-coding RNAs are still subjected to natural selection but the standard method of measuring this selection fails when every substitution, insertion or deletion can disrupt the ensemble of structures an RNA populates. However, these ensemble provide a way to measure and identify selection and random mutation in non-coding RNA in relation to more basal sequences. We describe this method as it applies to the small subunit of the ribosome from Escherichia coli. These results show a pattern of evolution for the small subunit; a single or a few mutations increases the diversity of structures which is then followed by selection, which subsequently reduces this diversity.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7eprtjivg4fdrad90c1d0703n4","2014-03-24 09:50:34","2014-03-25 11:43:36"
"2293","34",,"2014-04-23 10:00:00","2014-04-23 11:15:00","SAS 4201","Hui-Jie Lee",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5tv3rggpt66at2bb7buga6ojps","2014-03-24 10:22:37",NULL
"2296","34",,"2014-04-09 10:00:00","2014-04-09 11:15:00","SAS 4201","Kristin Lamm",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/61h0603k4teq0l7egc2a48b8rk","2014-03-25 11:41:48",NULL
"2299","31","Effects of emotion in swarming dynamics","2014-03-25 11:15:00","2014-03-25 12:15:00","SAS 4201","Jesus Rosado","http://www.math.ucla.edu/~jrosado/","UCLA",,,,"ldbookma","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/n9ts8a2idq64fdin76l3341vqg","2014-03-25 14:54:19",NULL
"2302","28","AWM Weekly Ladies Lunch","2014-03-26 12:30:00","2014-03-26 13:30:00","Undergraduate Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ml6f3k81iug6l6a1prr73tdbbc","2014-03-26 10:08:50",NULL
"2305","3","Planar algebras and evaluation algorithms","2014-04-07 14:30:00","2014-04-07 15:30:00","SAS 4201","Dave Penneys","http://www.math.toronto.edu/dpenneys","University of Toronto",,,"Jones planar algebras are a useful tool for studying and constructing
fusion categories, which generalize the representation categories of
(quantum) groups. Thus we think of fusion categories and planar
algebras as encoding quantum symmetries. I will give an overview of
Jones planar algebras with attention to specific examples. Along the
way, we will discuss several evaluation algorithms which give quantum
invariants, including the Jones polynomial.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3kudo611me6u744psemsl0sa9o","2014-03-26 11:01:54","2014-04-02 10:24:05"
"2308","9","Inherent demographic stability in mutualist-resource-exploiter interactions","2014-04-01 16:15:00","2014-04-01 17:15:00","Cox 306","Charlotte Lee","http://www.bio.fsu.edu/~ctlee/","Duke University","Kevin Gross",,"The ubiquity of natural mutualisms has challenged ecological theory, which predicts that mutualisms should experience destabilizing positive feedback, and should be vulnerable to extinction through competitive exclusion by less-mutualistic exploiter species.  Using an explicitly demographic approach, focused on resource demographic responses to mutualistic and exploitative partners, I show that indirect, demography-mediated interactions between mutualists and exploiters can both ensure mutualist-exploiter coexistence and also stabilize the abundances of mutualists, exploiters, and their shared resources.  This can occur in both long-lasting, exclusive interactions such as residential mutualisms, and in instantaneous mutualistic interactions such as pollination.  The key necessary factors, demographic responses to interspecific interaction and demographic structure, are common in natural populations.  Thus, the explicitly demographic approach and broad, multispecies perspective taken here constitute a potentially promising unified explanation for the apparent stability of mutualism in nature.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/siveu3e0nrtl9202taihap5fg8","2014-03-27 09:09:16",NULL
"2311","9","Bet-hedging and the evolution of adaptive plasticity","2014-04-08 16:15:00","2014-04-08 17:15:00","Cox 306","Jeremy van Cleve","http://tuvalu.santafe.edu/~vancleve/","National Evolutionary Synthesis Center","Kevin Gross",,"In light of an uncertain future, organisms face a difficult trade-off.  They can either specialize on a single phenotype across a range of environments, hedge their bets by randomly choosing among a set of phenotypes, or invest in physiological machinery to adjust their phenotype plastically to the environment.  Understanding the evolutionary relationship between these strategies remains a puzzle.  Here, we present a simple model for the evolution of specialization, bet-hedging, and plasticity that reveals how these strategies are fundamentally sensitive to how the fitness cost of sensing varies with plasticity.  When costs accelerate as a function of plasticity, the level of plasticity depends on how fast costs change.  In contrast, decelerating costs can lead to full adaptive plasticity, but only when initial conditions are right.  The shape of the cost curve is almost certainly due to the genetic and metabolic network machinery underlying plastic traits, which means that certain networks are more likely than others to evolve adaptive plasticity.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/80e9arac6m68jdhqfggc7mnm9k","2014-03-27 09:10:47","2014-04-04 18:18:06"
"2314","14","Departmental Tea and Cookies","2014-03-31 15:30:00","2014-03-31 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/f4mgq1saav7kuq6ghfq010ej44","2014-03-31 10:08:52",NULL
"2317","28","AWM Weekly Ladies Lunch","2014-04-02 12:30:00","2014-04-02 13:30:00","Undergraduate Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jivge02olod92lmotmku2q6aog","2014-03-31 11:30:34",NULL
"2320","28","AWM Weekly Ladies Lunch","2014-04-09 12:30:00","2014-04-09 13:30:00","Undergraduate Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bfbvg8igkr2sdfk8lrrfpg7fjo","2014-03-31 11:31:00",NULL
"2323","28","AWM Weekly Ladies Lunch","2014-04-16 12:30:00","2014-04-16 13:30:00","Undergraduate Lounge 2nd floor of SAS",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/jvmfvsf6mtntb7hu9ag91e4p9s","2014-03-31 11:31:40",NULL
"2326","28","AWM Weekly Ladies Lunch","2014-04-23 12:30:00","2014-04-23 13:30:00","Undergraduate Lounge 2nd floor of SAS",,,,,,"Last ladies lunch of the 2014 Spring semester.  Bring your lunch and well bring a delicious snack!","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i7lmjg0p4b4tca79t3gbl5umrs","2014-03-31 11:33:02",NULL
"2329","2","Hyperbolic Geometry in Maps and Networks","2014-04-22 16:30:00","2014-04-22 17:30:00","SAS 4201","Yuliy Baryshnikov","http://publish.illinois.edu/ymb/","University of Illinois, Urbana Champaign","Seth Sullivant",,"Hyperbolic geometry is playing a prominent role in computer sciences since quite a while. In this talk I describe some recently discovered - or refuted - manifestations of its usefulness in network science and user interfaces.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/an3blh521k3sgm12v0n0913k30","2014-04-01 13:02:08","2014-04-15 15:09:22"
"2335","26","Verification of Bayesian model calibration and parameter selection techniques for an HIV model","2014-04-07 16:00:00","2014-04-07 17:00:00","SAS 4201","Mami Wentworth",,"NC State",,,"Model calibration and parameter selection play an important role in uncertainty quantification. Before quantifying and propagating uncertainties in models, one must first calibrate input parameters that can not be measured. Additionally, most models have non-identifiable or non-influential parameters, which must be ascertained and fixed prior to uncertainty quantification. In this talk, we first discuss sampling-based Bayesian model calibration techniques, and use an HIV model introduced by Adams, Banks, Kwon, Tran, Wynne and Rosenberg in 2004 to verify the accuracy of these methods. We also investigate parameter selection techniques and discuss how the influential parameters for the HIV model compare among various methods.","ascoons","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ce8akrulqvu1ch9mk60ek428eg","2014-04-04 13:06:56",NULL
"2341","8","Connectivity in Semialgebraic Sets","2014-04-29 16:30:00","2014-04-29 17:30:00","SAS 4201","James Rohal","http://www4.ncsu.edu/~jjrohal/","NC State","Jon Hauenstein",,"A semialgebraic set is a subset of real space defined by polynomial equations and inequalities and is a union of finitely many maximally connected components. In this talk, we consider the problem of deciding whether two given points in a semialgebraic set are connected; that is, whether the two points lie in the same connected component. In particular, we consider the semialgebraic set defined by f != 0 where f is a given polynomial. The motivation comes from the observation that many important or non-trivial problems in science and engineering can be often reduced to that of connectivity. Due to its importance, there has been intense research effort on the problem. We will describe a symbolic-numeric method for solving this problem based on gradient ascent. We give proofs of partial correctness and termination of the symbolic method assuming the correctness of the numeric part. We will give an upper bound on the length of a path connecting the two input points if they lie in a same connected component. This is joint work with Hoon Hong, Mohab Safey El Din, and Eric Schost.","jdhauens","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v1epqku553mfkvtucbk0m4eulc","2014-04-07 15:56:47","2014-04-24 12:11:54"
"2344","4","Geometric theory of garden hose dynamics","2014-05-07 15:00:00","2014-05-07 16:00:00","SAS 4201","Vakhtang Putkaradze","http://www.ualberta.ca/~putkarad/","University of Alberta","Dmitry Zenkov",,"A garden hose inevitably wiggles and twists when water is rushing through it. We derive a fully three-dimensional, geometrically exact theory for this phenomenon. The theory also incorporates the change of the cross-section available to the fluid motion during the dynamics. Our approach is based on the symmetry-reduced, exact geometric description for elastic rods, coupled with the fluid transport and subject to the volume conservation constraint for the fluid. We analyze the linear stability, and show that the change of cross-section plays an important role. We derive and analyze several analytical, fully nonlinear solutions of traveling wave type in two dimensions. Time permitting, we shall also discuss the effects of the boundary conditions and experimental results. Partially supported by NSERC and the University of Alberta.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/uupo3a1c9d4607p1eejh5qgon0","2014-04-07 16:03:13","2014-04-29 23:25:56"
"2347","15","End of Year Meeting","2014-04-14 15:00:00","2014-04-14 16:00:00","SAS 1218",,,,,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/128tlo2hl022raovmomqqtnkec","2014-04-08 15:36:52",NULL
"2350","14","Departmental Tea and Cookies","2014-04-09 14:30:00","2014-04-09 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rq8i3htdgmapidpb2uhj18g538","2014-04-09 14:39:20",NULL
"2353","21","College of Sciences Honors Celebration","2014-04-14 15:00:00","2014-04-14 16:30:00","Riddick Hearth",,,,,,"The College of Sciences will have an Honors Celebration on Monday, April 14, 2014, 3:00-4:30 pm, at the Riddick Hearth. There will be a reception and a formal program. Graduating seniors in departmental honors programs, graduating seniors completing the University Honors Program or the University Scholars Program, and the college senior awards recipients will be recognized.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/5dfch43je4v6c0c91bsf3kj770","2014-04-10 10:28:50",NULL
"2356","21","Kwangil Koh Reception","2014-04-14 16:00:00","2014-04-14 16:30:00","SAS Second Floor Lobby",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/0l3snrv824tll81290mr2ptuto","2014-04-10 10:31:09",NULL
"2359","28","AWM Ice Cream Social and Elections!","2014-04-15 16:00:00","2014-04-15 17:00:00","SAS 1102",,,,,,"We will be having our end of year meeting including officer elections and an ice cream social.  Please join us in celebrating a great year and preparing for a new one!","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/eefpl9h9fnoa968j0k6it6v46c","2014-04-11 09:55:57","2014-04-14 14:56:42"
"2362","4","Recent results in nonholonomic mechanics","2014-04-21 15:00:00","2014-04-21 16:00:00","SAS 4201","Olga Rossi",,"University of Ostrava","Dmitry Zenkov",,"In presence of constraints depending on velocities (i.e. given by a system of first order ODEs) one can investigate Lagrangian systems either from a mechanical or a geometrical point of view.The former approach reflects the physical understanding of constrained dynamics as motions in the original configuration space subject to reactive forces  expressing the constraints.Mathematically this leads to equations of motion with Lagrange multipliers, known as Chetaev equations. We adopt the latter viewpoint reflecting a geometrical understanding of constrained dynamics as a motion on a submanifold of the first jet bundle, the so-called constraint manifold. This model leads to a reduced system of equations where the unknown reaction forces are absent (equationswithout Lagrange multipliers, equivalent with Chetaev equations). Remarkably, the geometric approach provides a unified treatment of both Lagrangian and non-Lagrangian systems subject to general (nonlinear non-ingerable) velocity dependent constraints. In particular, I shall present a solution of a longstanding problem about the existence of a variational principle for nonholonomic systems, and a corresponding Noether theorem.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sumukkp9j378qedmh86l60ken4","2014-04-14 13:21:24",NULL
"2365","24","MGSA BBQ and elections","2014-04-15 17:00:00","2014-04-15 18:30:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/akd8nls94g982fpn0ba0sd55ag","2014-04-15 09:41:27",NULL
"2368","14","Departmental Tea and Cookies","2014-04-16 14:30:00","2014-04-16 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ns52ugbav0du412t93t79fibp0","2014-04-16 12:43:47",NULL
"2371","14","Spring 2014 Undergrad Research Presentations","2014-04-22 16:00:00","2014-04-22 17:00:00","SAS 2102",,,,,,"1.  Robert OBrien and Brett Yarchin

Title  :  Optimizing Wolbachia Release Strategies for Controlling Dengue Fever

Abstract :  Dengue fever is the most prevalent mosquito-borne viral
disease that affects humans. Since there are no licensed vaccines or
effective drug treatments currently available, disease control efforts
have largely focused on controlling the vector of the disease, the
mosquito Aedes aegypti. While traditional vector control methods, such
as insecticide spraying and source reduction, can have a major impact
on reducing transmission of the infection, they often require an
intensive control effort and are difficult to maintain on a long-term
basis. One new control measure that has been proposed involves the
introduction of a strain of the bacterium Wolbachia into a native
mosquito population. Infection with Wolbachia has been shown to reduce
transmission of dengue virus, and it is thought that replacing a
native mosquito population with one which is entirely infected with
Wolbachia will lead to decreased incidence of dengue. Carefully
planned releases of Wolbachia-infected mosquitoes are needed to
effectively lower disease incidence while making efficient use of
available resources. To this end, we applied principles of optimal
control theory to design and assess potential release strategies.
(Under supervision of Dr. Alun Lloyd and Dr. Michael Robert)
-------------------------------------------------------------------------------------
2. Nicholas Quayle

Title :  Beyond the Bounds of the Riemann Integral

Abstract : The Riemann integral is taught in calculus courses all over
the country. This makes sense; it is easy to define and understand for
students even in high school. In this presentation we take a look at
the limitations of the Riemann integral, and why we need something
more powerful. We will develop sigma algebras and measure theory, in
order to define the Lebesgue integral, and then examine the properties
which make it more desirable than its Riemann counterpart. We will
also take a look at functions of bounded variation, and use those to
develop the Riemann - Stieltjes integral.
-------------------------------------------------------------------------------------
3.  Jacob Robbins

Title : An Algebraic Method for Constructing Stable and Consistent
Autoregressive Filters

Abstract : In many fields of meteorology and physics, it is necessary
to filter noisy observations of non-linear signals.  This project
provides an algebraic method to construct stable and consistent
autoregressive models of low order to be used for such filtering.
Here, consistent refers to the classical consistency constraints of
linear multistep methods of order-two.  Stable refers to the
classical stability condition for the AR model.  This stability
condition is equivalent to the selection of parameters such that the
complex roots of a certain polynomial lie strictly within the unit
circle.  My main contribution to the project was to study how to
select these parameters in a way that robustly yields stability.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/pmlvi684sf45c4e441mrbsh94o","2014-04-21 11:00:38",NULL
"2374","14","Spring 2014 Undergrad Research Presentations","2014-04-23 16:00:00","2014-04-23 17:00:00","SAS 2102",,,,,,"1.   Robert Baraldi

Title : The e&amp;#64256;ects of reparametrization on inverse problems

Abstract :  We consider two systems, the logistic-growth population
model and the spring-mass model. These models are each parameterized
in two different ways: one where the parameters are independent of one
another and one where they are dependent. First, we perform the
uncertainty quantification method of asymptotic theory using ordinary
least squares on each model, and then look for signs of parameter
dependence in the off-diagonal elements of the Fisher Information
matrix by comparing the matrix created by dependent and independent
results. Next, we compare the confidence intervals generated by
asymptotic theory to those created by the bootstrapping technique of
uncertainty quantification. We do this by creating confidence
ellipsoids from the information present in the covariance matrices.
Finally, we show that the parameter dependencies are shown by
bootstrapping in the form of parameter distributions, but not by
asymptotic theory.
-------------------------------------------------------------------------------------
2.  Christian Chapman

Title : Methods for Multiframe Super-Resolution

Abstract : A high-resolution image is desired from a series of
spatially-offset low-resolution images of a scene. A solution using
Fourier Deconvolution is derived. The solution is evaluated by
measuring improvement in the Contrast Transfer Function of data
processed by the technique against original image data and known
techniques. It is seen that the Fourier Deconvolution technique
performs roughly 3 times better than methods using prior Wiener
deconvolution and prior Lucy-Richardson deconvolution.
-------------------------------------------------------------------------------------
3.  Christopher Paquette

Title :  Markov chains of evolutionary graphs over birth first and
death first selection

Abstract :  We study evolutionary graphs and the evolution of their
populations over time, using different models of birth and death.
Both models are explored using the Markovian properties to show their
fixation probabilities.  We compare these models and show that they
are not identical, and that the difference is correlated with the
fitness of the mutant individuals.  It is shown that in the case where
all individuals are capable of producing individuals of either group
that so long as every individual is capable of being replaced there is
a probability of 1 that at some time the entire population will be
composed so mutant individuals.

-------------------------------------------------------------------------------------
4.  Kelsey Reppert

Title :  Optimization of Klystrons Using MATLAB Methods

Abstract :  Klystrons are wave amplifiers that contain several
different design parameters that change based on their applications.
Currently, the klystron engineers use different computer programs to
iteratively guess and check on what the design parameters should be on
each klystron. However, we could make this method more efficient by
using a mathematical minimization algorithm. We aim to create a
program to make the design process of a klystron more efficient by
searching for an optimal design with an optimization routine.
-------------------------------------------------------------------------------------","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6cgbngekhd9gtlgategfdntgr4","2014-04-21 11:01:42",NULL
"2377","24","First Annual Mathematics Graduate Student Research Symposium","2014-04-24 13:00:00","2014-04-24 14:00:00","SAS 2225",,,,,,"Thank you to those of you who RSVPd to our lunch and presentation this Thursday, April 24. If you havent, we still have a few spaces left so feel free to add your name to the RSVP list.

If you RSVPd, please join us in the fourth floor commons (SAS 4104) this Thursday at 12:00 PM for lunch.

If you are not interested in lunch, but you are interested in our graduate students research, please feel free to stop by our poster presentations in SAS 2225 at 1:00 PM.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/m47hcfomjbhcu8rodqmrrcqh9o","2014-04-22 09:35:24",NULL
"2380","14","Departmental Tea and Cookies","2014-04-22 16:00:00","2014-04-22 16:30:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/sbh1o1o03v5j5r3nf1l8ivt1ek","2014-04-22 11:41:44",NULL
"2384","14","Departmental Tea and Cookies","2014-04-30 14:30:00","2014-04-30 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/mcflmb8q6ua7nv9k8bp8k3oj5c","2014-04-30 11:29:23",NULL
"2387","3","The BV formalism for L infinity algebras","2014-05-08 14:00:00","2014-05-08 15:00:00","SAS 4201","Alexander A. Voronov","http://www.math.umn.edu/~voronov/","University of Minnesota",,,"We interpret the theory of L_infty algebras using the BV formalism. Namely, we show how L_infty algebras give rise to BV_infty algebras and vise versa, and identify the category of L_infty algebras with a subcategory of BV_infty algebras. This construction is used in studying r_infty matrices and L_infty bialgebras.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ot7hka43tphsrupdj3nptmssss","2014-05-05 10:01:48",NULL
"2390","14","NC State Mathematics Spring 2014 Graduation","2014-05-09 15:00:00","2014-05-09 17:00:00","SAS 2203",,,,,,"The Mathematics Departmental Graduation will be held on Friday, May 9 at 3:00 p.m. in 2203 SAS Hall.  Reception will follow the ceremony.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1i8jv9qsmb46uustc8famdbtek","2014-05-07 10:08:42",NULL
"2394","38","On the Cross Section Lattice of Reductive Monoids - advised by Mohan Putcha","2014-06-20 15:00:00","2014-06-20 16:00:00","SAS 3282","Stephen Adams",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/8tmp4pe05g1cvsr8utubn7pkog","2014-05-29 12:09:07","2014-06-19 11:42:00"
"2397","38","Representations of Toroidal Lie Algebras - advised by Naihuan Jing and Kailash Misra","2014-06-26 13:00:00","2014-06-26 14:00:00","SAS 3282","Chad Mangum",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/nh6pslssheo3akderibppbfn38","2014-05-29 12:10:08","2014-06-19 11:42:20"
"2400","38","Solving Nonlinear Constrained Optimization Time-Delay Systems with a Direct Transcription Approach - advised by Steve Campbell","2014-06-27 14:00:00","2014-06-27 15:00:00","SAS 2102","Karmethia Thompson",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/uf0vtp1rmpde9gg9k0p3vhhebo","2014-05-29 12:11:50","2014-06-26 10:38:29"
"2403","38","Demazure Crystals for the Quantum Affine Algebra UqD43 - advised by Kailash Misra","2014-06-30 13:00:00","2014-06-30 14:00:00","SAS 3282","Alyssa Armstrong",,"NC State ",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/d28mad0jj3h35ad7oh33gu85o4","2014-05-29 12:12:46","2014-06-19 11:43:21"
"2406","38","Cell Proliferation Models, CFSE-Based Flow Cytometry Data, and Qualification of Uncertainty - advised by HT Banks","2014-07-15 14:00:00","2014-07-15 15:00:00","Cox 306","Dustin Kapraun",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/q65gielhkk3apl5iuhlrrddpco","2014-05-29 12:13:31","2014-06-19 11:43:46"
"2409","38","A Study on a Non-Markovian Random Walks - advised by Min Kang","2014-08-18 13:00:00","2014-08-18 14:00:00","SAS 3282","Thanawit Jeeruphan",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/5doo6kbukqik906evfg7ggdfhs","2014-05-29 12:14:34","2014-06-19 11:44:19"
"2412","38","Classification of orbifold modules under an isometry of order 2","2014-07-24 14:00:00","2014-07-24 15:00:00","SAS 4201","Jason Elsinger",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/u54b2tdevnq1lrdrvspk4ctg0g","2014-06-06 11:09:40","2014-07-09 11:30:39"
"2413","38","Local unitary equivalence of quantum states","2014-06-27 13:00:00","2014-06-27 14:00:00","SAS 3282","Min Yang",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/eiu6jo8261ab13op10tcgdir0s","2014-06-11 10:40:09","2014-06-19 11:42:43"
"2415","21","NSF-CBMS Regional Conference on Higher Representation Theory","2014-07-06 08:00:00","2014-07-10 18:00:00","NC State University",,,,,"http://www.math.ncsu.edu/~jing/conf/CBMS/cbms14.html",,"schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/593isq9c368ba9aor4lue2kbpc","2014-06-19 11:38:42","2014-06-27 10:48:39"
"2419","6","Approximate Separability of Greens Function for Helmholtz Equation in the High Frequency Limit","2014-10-07 15:00:00","2014-10-07 15:50:00","SAS 4201","Hongkai Zhao","http://www.math.uci.edu/~zhao","University of California, Irvine","Alina Chertok",,"Approximate separable representations of Greens functions for differential operators is a basic and important question in the analysis of differential equations,  the development of efficient numerical algorithms and imaging. Being able to approximate a Greens function as a sum with few separable terms is equivalent to low rank properties of corresponding numerical solution operators. This will allow for matrix compression and fast solution techniques. Greens functions for coercive elliptic differential operators have been shown to be highly separable and the resulting low rank property for discretized system was explored to develop efficient numerical algorithms. However, the case of Helmholtz equation in the high frequency limit is more challenging both mathematically and numerically. We introduce new tools based on the study of relations between two Greens functions with different source points and a tight dimension estimate for the best linear subspace approximating a set of almost orthogonal vectors  to prove new lower bounds for the number of terms in the representation for the Greens function for Helmholtz operator in the high frequency limit. Upper bounds are also derived. We give explicit sharp estimates for cases that are common in practice and present numerical examples. This is a joint work with Bjorn Engquist.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0d20vj8vof50q4rn2u2d816ri8","2014-07-08 12:05:36","2014-07-08 19:33:31"
"2422","36","First Year Research Seminars","2014-09-05 15:00:00","2014-09-05 16:00:00","SAS 4201","Tim Kelley and Agnes Szanto",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/b7s0uk40gte3hnkr3jai9h90j8","2014-07-25 08:42:27","2014-08-09 15:39:01"
"2425","36","First Year Research Seminars","2014-09-19 15:00:00","2014-09-19 16:00:00","SAS 4201","Ralph Smith and Irina Kogan",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/j6vmdf8ss16fnm9pj6k3c01cus","2014-07-25 08:43:51","2014-09-15 10:32:19"
"2428","36","First Year Research Seminars","2014-10-03 15:00:00","2014-10-03 16:00:00","SAS 4201","Alina Chertock and Alun Lloyd",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2qj76jd5jn06hn3c4qc25ka5vk","2014-07-25 08:44:19","2014-10-03 10:23:02"
"2431","36","First Year Research Seminars","2014-10-24 15:00:00","2014-10-24 16:00:00","SAS 4201","David Papp and Andrew Cooper",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h90u10sa2muu1ndk2mm3fquugg","2014-07-25 08:45:15","2014-10-21 10:07:48"
"2434","36","First Year Research Seminars","2014-10-31 15:00:00","2014-10-31 16:00:00","SAS 4201","Lorena Bociu and Nathan Reading",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/goera2j83o7o1k0v3vp4du2eic","2014-07-25 08:45:53","2014-10-21 10:08:44"
"2437","36","First Year Research Seminars","2014-11-14 15:00:00","2014-11-14 16:00:00","SAS 4201","Jesus Rodriguez and Jessica Matthews",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0tb0j3vc8c5n94b5cict3bvd0k","2014-07-25 08:46:27","2014-11-11 09:36:26"
"2440","1","Optimal tilings","2015-04-13 16:00:00","2015-04-13 17:00:00","SAS 1102","Frank Morgan","http://math.williams.edu/morgan/","Williams College","Michael Singer",,"Regular hexagons provide the most efficient, least-perimeter, unit-area tiling of the plane, as was finally proved by Hales in 2000. Is there a best tiling by pentagons? What about higher dimensions? The presentation will include new results, some by undergraduates, and open questions.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/17m7819sq70mm4d586l27ekkr4","2014-07-25 15:57:21","2015-02-13 13:09:52"
"2443","24","MGSA Study Break","2014-08-07 14:30:00","2014-08-07 16:30:00","SAS 4104",,,,,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/a1v75o106a9887p4h7gobnsb9s","2014-07-29 14:21:24",NULL
"2446","21","Tutorial Workshop on Parameter Estimation for Biological Models","2014-08-08 08:00:00","2014-08-11 17:00:00","SAS Hall, NC State",,,,"Adam Mahdi, Mette Olufsen and Alun Lloyd","http://rtg.math.ncsu.edu/workshop/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gd9188ihv2jh6aj36jbeoekg6c","2014-07-29 15:46:38","2014-07-29 17:13:48"
"2449","6","The Modified RayleighBenard Convection Problem and its Application to Greenhouse Gas Emissions Simulation","2014-09-15 15:00:00","2014-09-15 15:50:00","SAS 2102","Ivan Sudakov","https://faculty.utah.edu/u0851393-Ivan_Sudakov/research/index.hml","U of Utah","Alina Chertock",,"The original RayleighBenard convection is a standard example of the system where bifurcations occur with changing of a control parameter. I will discuss the modified RayleighBenard convection problem which includes the radiative effects as well as the specific gas sources on a surface. Such formulation of this problem leads to identification a new kind of bifurcation phenomenon, besides the well-known Benard cells.

    Modeling of greenhouse gas emissions into the atmosphere drives to difficult problems, involving the Navier-Stokes equations. There exist climate models with different levels of realism. Usually, one investigates these models by computer simulations. However, it is difficult to the estimate reliability of these computations, since it is connected with a complex mathematical problem on the structural stability of attractors. Taking into account the modified RayleighBenard convection problem, I will discuss a new approach which makes the problem of a climate catastrophe in the result of a greenhouse effect more mathematically tractable and allows us to describe catastrophic bifurcations in the atmosphere induced by soil greenhouse gas sources.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2batdnpfpc2vk0ci2a0hukekac","2014-07-30 15:02:10","2014-08-26 13:42:48"
"2452","43","Recent developments on reduced-order methods for high-dimensional kinetic equations","2014-09-16 15:00:00","2014-09-16 15:50:00","SAS 4201","Daniele Venturi","http://www.dam.brown.edu/people/venturi/Home.htm","Brown University","Pierre Gremaud","http://www.math.ncsu.edu/~gremaud/daniele.pdf",,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/emkr2mnrruvncfoicgnl89sduo","2014-08-06 09:11:08","2014-08-26 13:59:16"
"2455","6","Anderson Acceleration","2014-09-09 15:00:00","2014-09-09 15:50:00","SAS 4201","Tim Kelley","http://www4.ncsu.edu/~ctk/","NC State","NA Seminar",,"Anderson acceleration is an algorithm for accelerating the convergence
of fixed point or Picard iteration. The method was invented in 1965
to accelerate the SCF iteration in electronic structure computations
and is now widely used in that field. 
Anderson acceleration does not require the computation
or approximation of Jacobians or Jacobian-vector products, and this
can be an advantage over Newton-like methods. 

There is little theory for the method. One can show that the method 
is related to GMRES for linear problems and to multi-secant methods
for nonlinear problems. However, results of this type do not lead
to convergence theory for the way that the method is used in practice.

In this talk we will discuss the first convergence results for the
method, illustrate the results with an application to radiative transport, discuss issues with multi-physics coupling, and list a few open questions.

This is joint work with Alex Toth. This talk is the followup to my talk for the students in the First Year Seminar, where I promised to show them more math. Here is that more math.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kcn0tghrmo4jsuuifpdsfi72eo","2014-08-06 16:16:28",NULL
"2458","28","Beginning of the Year Welcome  Speed Friending","2014-08-21 16:30:00","2014-08-21 17:30:00","SAS 2102",,,,,,"We will be hosting a speed friending event to provide a forum for low-stress communication and exposure to various students, staff, and faculty members in the math department.  It is intended primarily as a way to introduce undergraduate and new graduate students to the department while being provided with some tasty treats!","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2cpl03bqnv4tq1e1qgllav0q84","2014-08-12 11:33:11","2014-08-12 11:34:58"
"2461","34","On the size of the maximum agreement subtree","2014-08-20 10:00:00","2014-08-20 11:15:00","SAS 4201","Seth Sullivant",,"NC State",,,,"smsulli2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/vlis00opo9h43tf9dm1o5i650o","2014-08-14 17:09:07",NULL
"2464","43","Rational Krylov Approximation of Matrix Functions and Applications","2014-09-08 15:00:00","2014-09-08 15:50:00","SAS 2102","Stefan Guettel","http://www.guettel.com","University of Manchester","Pierre Gremaud",,"Some problems in scientific computing, like the forward simulation of electromagnetic waves in geophysical prospecting, can be solved via approximation of f(A)b, the action of a large matrix function f(A) onto a vector b. Iterative methods based on rational Krylov spaces are powerful tools for these computations, and the choice of parameters in these methods is an active area of research. We provide an overview of different approaches for obtaining optimal parameters, with an emphasis on the exponential and resolvent function, and the square root. If time permits, we will discuss a surprising new application of the rational Arnoldi method for iteratively generating near-optimal absorbing boundary layers for indefinite Helmholtz problems.","bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/rma2ds2jn9tnrsui5cle5b6jco","2014-08-15 13:22:47","2014-09-02 11:31:00"
"2467","34","Maximum parsimony and maximum likelihood approaches to microsatellite data analysis","2014-11-05 10:00:00","2014-11-05 11:00:00","SAS 4201","Leonid Chindelevitch","http://people.csail.mit.edu/leonidus","Harvard School of Public Health",,,"Microsatellite data has received relatively little interest in phylogenetics despite its rich structure. In this talk, we introduce a class of evolutionary models for microsatellite data for which the ancestral genome reconstruction problem in a maximum parsimony framework can be solved in time linear in the number of sequences, independently of copy number magnitude, and show that two classic models fall into this class. For the maximum likelihood framework, we describe how the ancestral genome reconstruction problem can be solved efficiently for this class of models by leveraging sparsity. We also discuss the application of these methods to two datasets obtained from a tuberculosis epidemic in South Africa.","smsulli2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2810dl34anlvdr7ua38d3lg400","2014-08-18 11:05:11","2014-10-24 13:46:10"
"2470","14","Mathematics Fall Departmental Meeting","2014-08-25 16:00:00","2014-08-25 17:00:00","SAS 1102",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/emoiilv7dde4j9g3l9uvktal5o","2014-08-18 15:04:40",NULL
"2473","14","Mathematics Fall Meeting Reception","2014-08-25 15:30:00","2014-08-25 16:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/lss8m7lpm3r07q1tb386qnqug4","2014-08-18 15:05:18",NULL
"2476","27","Special Session on Geometric Analysis, AMS SE Sectional Meeting","2014-11-08 08:00:00","2014-11-09 17:00:00","UNC Greensboro",,,,"Andrew Cooper","http://e-math.ams.org/meetings/sectional/2222_special.html",,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/tqf838r7kmint9nemkphr145ic","2014-08-20 11:09:36",NULL
"2479","1","The dynamics of calcium: oscillations and waves, experiments and theory","2014-11-05 16:00:00","2014-11-05 17:00:00","SAS 1102","James Sneyd","https://www.math.auckland.ac.nz/~sneyd/","University of Auckland","Sharon Lubkin",,"Oscillation in the cytoplasmic concentration of calcium is one of the most ubiquitous cellular signaling mechanisms. It is used to control a wide variety of cellular processes, including muscular contraction, fluid transport, gene expression, and cell differentiation. In cells that are large enough, these oscillations can form periodic waves, or even spiral waves, of increased calcium concentration.

Because of such complex dynamics, over the past twenty years mathematical modeling has played an important role in the study of calcium signaling. I shall present an overview of the field, as well as a more in-depth look at a small number of particular questions. In particular, I shall look at the properties of isolated and periodic waves of calcium, the importance of homogenization and microdomains, the role of Markov Chain Monte Carlo approaches to fitting single-channel data, and the possible importance of homoclinic bifurcations for understanding some of the most recent experimental results. Each of these topics will require a detailed consideration of experimental data, thus illustrating the close interplay between theoretical and experimental approaches.","schecter","1","https://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/1gd0r6971dth2prhju2lckfeh4","2014-08-21 10:35:48","2014-10-13 11:02:42"
"2482","34","Finding almost perfect phylogenies via intersection graph triangulations","2014-08-27 10:00:00","2014-08-27 11:00:00","SAS 4201","Rob Gysel",,"UC Davis",,,"The perfect phylogeny problem (aka  character compatibility problem) asks if a set of characters simultaneously obeys the infinite sites assumption on some tree (a perfect phylogeny). When no such tree exists, it is natural to ask for the largest (weighted) set of characters that do have a perfect phylogeny (maximum compatibility). A special case of maximum compatibility is maximum quartet consistency, a problem that arises from statistical phylogenetics. In this talk, I will outline the relationship between perfect phylogeny and graph triangulations, first described by Buneman in 1974. Graph triangulations have long been used to study the tractability and structural properties of the perfect phylogeny problem and its variants. Triangulations also allow for exact and heuristic-based solutions to maximum compatibility (and maximum quartet consistency). I will briefly sketch the history of this field since Bunemans original paper, its current status, and if time permits, potential future directions","smsulli2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/bp3pcma7fj7jvp9hdh2dk87cvk","2014-08-21 15:40:27","2014-08-21 15:42:31"
"2485","28","AWM Brown Bag Lunch","2014-08-26 12:00:00","2014-08-26 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ntc5ikl7m7438nn3ovmi06rkhs","2014-08-21 20:14:04",NULL
"2488","28","AWM Brown Bag Lunch","2014-09-02 12:00:00","2014-09-02 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/hemc5dks6g1al29jf9rf6f21js","2014-08-21 20:14:52",NULL
"2491","6","Monte Carlo Synthetic Acceleration Algorithms for Linear Systems","2014-11-04 15:00:00","2014-11-04 15:50:00","SAS 4201","Stuart Slattery",,"Oak Ridge National Laboratory","NA and NE seminars",,"Monte Carlo Synthetic Acceleration (MCSA) algorithms for linear systems are currently being researched as a potential scalable and resilient linear solver for exascale computing systems. Our team is focusing on several aspects of these algorithms including basic theory, preconditioning, parallelism, performance modeling, and resiliency. In this talk I will provide an introduction to solving linear systems with Monte Carlo initially developed by Von Neumann and Ulam followed by an outline of the MCSA scheme. I will then discuss some of our recent algorithmic developments aimed at enabling both better iterative performance as well as hybrid parallelism. I will then present a domain decomposition scheme we have developed for the algorithm based on parallel Monte Carlo particle transport schemes. I will end the talk by giving results for both a linearized form of the transient radiation diffusion equation as well as a SPn discretization of the neutron transport equation for light water reactor problems.","ctk","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/jb9vi8m61ir48jdcr8j4524vms","2014-08-24 09:57:02","2014-10-13 10:45:31"
"2494","43","Active control of electromagnetic fields","2014-09-30 15:00:00","2014-09-30 16:00:00","SAS 4201","Daniel Onofrei","http://www.math.uh.edu/~onofrei/","U of Houston","Pierre Gremaud",,"In this talk we will discuss the problem of control of electromagnetic fields by using active sources (antennas), i.e., characterization of surface currents needed on the active sources so that their radiated fields will approximate desired patterns in several given disjoint external regions. Mentioning that any realistic design will need to consider a series of important feasibility constraints, this problem can be placed at the intersection of several exciting research areas: inverse source problems, optimal control of PDEs, antenna synthesis and optimization theory.

In the first part of the talk, after a brief introduction of the subject, we will discuss the problem of controlling transverse normal modes in a wave guide.  We will present our analytical approach, discuss the feasibility of the approach and conclude with several relevant numerical results. Our analysis indicates, among other things, that the proposed control strategy seems to be feasible only in the near field region of the defending antenna.

In the second part of the lecture we will present the extension of our results to the case of free space electromagnetics, discuss the feasibility of the approach in this general context, and highlight several future research goals and the challenges we anticipate for this project.","gremaud","1","https://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/o910mjabsdrjhd5m6vonumi2ac","2014-08-26 09:03:22","2014-09-15 17:24:59"
"2497","4","Nonexistence of minimizers to some variational principles with nonlocal repulsive interactions","2014-10-15 15:00:00","2014-10-15 16:00:00","SAS 4201","Jianfeng Lu","http://www.math.duke.edu/~jianfeng/","Duke University ",,,"Variational principles with competing attractive and repulsive interactions often arise from physical applications. In this talk, we will consider variational models with Coulomb repulsion from electronic structure theory. We will present some recent progress on understanding these variational problems, in particular, the issue of existence of minimizers.","lvbociu","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/c67sgdmfqgsj0t7lmj21cukh6o","2014-08-27 11:27:08","2014-10-03 09:32:41"
"2500","15","SIAM Meeting","2014-09-09 11:35:00","2014-09-09 12:40:00","MANN 404","Stefan Guettel","http://www.guettel.com","University of Manchester",,,,"mestrait","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/51qj9949lunjnc6r5q0o4dajlk","2014-08-27 15:13:48","2014-08-27 15:14:19"
"2503","24","Pizza Party","2014-09-03 17:15:00","2014-09-03 19:00:00","SAS 4104",,,,"MGSA",,,"spolste","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/p1p5u5kptfi2rb8j5g1fii3sgg","2014-09-02 11:48:29",NULL
"2506","23","Applying for Graduate Fellowships","2014-09-12 15:00:00","2014-09-12 16:00:00","SAS 4201","Seth Sullivant",,"NC State",,,"Ill discuss how to go about applying for graduate research fellowships.  The focus will be on the National Science Foundation Graduate Research Fellowship but the basic principles apply to many other fellowships as well.  There will also be a Q&amp;A session with some past winners.","smsulli2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/9jftdlpl2qikcf7ge4nvdfg18g","2014-09-02 15:47:42",NULL
"2512","4","Codiagonalization of Matrices and Existence of Multiple Homoclinic Solutions","2014-09-24 15:00:00","2014-09-24 16:00:00","SAS 4201","Xiao-Biao Lin","http://www4.ncsu.edu/~xblin/","NC State",,,"Consider an autonomous ordinary differential equation in R^n that has a homoclinic solution asymptotic to a hyperbolic equilibrium. The homoclinic solution is degenerate in the sense that the linear variational equation has 2 bounded, linearly independent solutions. We study bifurcation of the homoclinic solution under periodic perturbations. Using matrices codiagonalization, exponential dichotomies and Lyapunov-Schmidt reduction, we obtain general conditions under which the perturbed system can have transverse homoclinic solutions and nearby periodic or chaotic solutions.","lvbociu","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2tjee6i1hsajd1hn1oqfndgmjs","2014-09-03 09:49:44","2014-09-08 14:13:58"
"2515","14","Departmental Tea and Cookies","2014-09-03 14:30:00","2014-09-03 15:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/7751qe21bl0asfosk40utcj51o","2014-09-03 10:40:57",NULL
"2518","4","A nonlinear, degenerate parabolic equation modeling methane hydrate formation in seafloor sediment","2014-10-22 15:00:00","2014-10-22 16:00:00","SAS 4201","Justin Webster","http://www4.ncsu.edu/~jtwebste/JustinsHomepageHome.html","NC State",,,"We consider a model of methane hydrate formation in shallow seafloor sediment which includes advective methane flux and mixed boundary conditions. We describe the derivation of the model from conservation of methane mass and Gibbs phase rule. We then cast the problem as a nonlinear evolution in L^1 involving a measurable family of graphs. In the absence of advective terms---and with Dirichlet boundary conditions---previous work connected the dynamics to a generalized porous medium equation cast on the space H^{-1}. By considering the weaker notion of C^0 solutions (Crandall-Liggett-Benilan) in the space L^1, we may utilize an extension of classic work by Brezis and Strauss in the 1970s on nonlinear elliptic equations with measure data. Working in the semigroup context, we: (1) obtain well-posedness of the Cauchy problem, and (2) demonstrate a useful maximum principle which guarantees that physical data corresponds to (appropriately) bounded solutions.","lvbociu","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k5akb88m867f8r1a1kcfkt3m0o","2014-09-03 11:29:14","2014-10-16 10:24:57"
"2521","46","Introduction to Operads in Topology and Algebra","2014-09-11 15:00:00","2014-09-11 16:00:00","SAS 4201","Tom Lada","http://www4.ncsu.edu/~lada/","NCSU",,,"Operads were originally invented to attack the topological problem of identifying iterated loop spaces.  I will outline these results and present several different examples of operads.  This will lead up to the current application of operads in a variety of algebraic settings.","aacoope2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/levap16oksnhsitkbnfk1fkf44","2014-09-04 22:25:28","2014-09-10 23:00:57"
"2524","19","Free Lattices","2014-09-10 15:00:00","2014-09-10 16:00:00","TBA","Emily Barnard",,"NC State Mathematics Graduate Student",,,,"esbarnar","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0asu00rv9ma353tq3midgv7gec","2014-09-08 10:40:45",NULL
"2527","14","NC State Mathematics Fall Graduation 2014","2014-12-17 15:00:00","2014-12-17 17:00:00","SAS 2203",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/q9rj5v73e318gggk8srnu1l9c0","2014-09-08 11:28:43",NULL
"2530","28","AWM Brown Bag Lunch","2014-09-09 12:00:00","2014-09-09 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1iq5frd5odfp83a23m8e0qop5g","2014-09-08 17:41:53",NULL
"2533","28","AWM Brown Bag Lunch","2014-09-16 12:00:00","2014-09-16 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8ueaoqkd7brsp38kltjkqvs0qk","2014-09-08 17:42:23",NULL
"2536","28","AWM Brown Bag Lunch","2014-09-23 12:00:00","2014-09-23 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/rmuu09tq9n6evg6dd6ug875bbk","2014-09-08 17:42:51",NULL
"2539","14","Departmental Tea and Cookies","2014-09-08 16:00:00","2014-09-08 16:30:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/svjohol563sggku61k549nkn90","2014-09-09 09:36:02",NULL
"2542","4","Concatenated Traveling Waves","2014-09-17 15:00:00","2014-09-17 16:00:00","SAS 4201","Stephen Schecter","http://www4.ncsu.edu/~schecter/","NC State",,,"We consider concatenated traveling wave solutions of reaction-diffusion systems.  These are solutions that look like a sequence of traveling waves with increasing velocity, with the right state of each wave equal to the left state of the next.  I will present an approach to the stability theory of such solutions that is based on exponential dichotomies and Laplace transform.  This is joint work with Xiao-Biao Lin.","lvbociu","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/d8ul0oinkuuqal1qusp6k6q6p8","2014-09-10 11:58:04",NULL
"2545","1","Lie algebras and combinatorial identities","2014-10-16 16:00:00","2014-10-16 17:00:00","SAS 1102","Kailash Misra","http://www4.ncsu.edu/~misra","NC State Distinguished Faculty Colloquium",,,"Lie groups were discovered by Sophus Lie around 1880 while searching for a framework to analyze continuous symmetries of differential equations in much the same way that permutation groups are used in Galois theory to analyze discrete symmetries of algebraic equations. A key idea in the theory of Lie groups is to replace the global object, the group, with its local or linearized version, which Lie called its &quot;infinitesimal group,&quot; now known as its Lie algebra. Around 1940, after Elie Cartans beautiful classification of finite-dimensional semisimple Lie algebras, Lie algebras emerged as an independent field of study. A class of infinite-dimensional Lie algebras generalizing the finite-dimensional semisimple Lie algebras was discovered independently by Victor Kac and Robert Moody in 1968. A subclass known as affine Lie algebras has proved to have important interactions with many areas of mathematics and physics. One such interaction is with number theory, particularly combinatorial identities. In this talk I will give an overview of some of my own contributions to this area.","schecter","1","https://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/2f0v9kugkqumtkp08m7esnjtog","2014-09-10 13:43:54","2014-09-10 13:45:17"
"2548","43","Global well-posedness for a relaxed Landau equation","2014-10-28 15:00:00","2014-10-28 16:00:00","SAS 4201","Maria Pia Gualdani","http://home.gwu.edu/~gualdani/","George Washington U","Pierre Gremaud",,"We present global well-posedness results for a relaxed version of the Landau equation with Coulomb potential. Despite lack of a comparison principle for the equation, the proof of existence relies on barrier arguments and parabolic regularity theory. The Landau equation arises in kinetic theory of plasma physics. It was derived by Landau and serves as a formal approximation to the Boltzmann equation when grazing collisions are predominant.","gremaud","1","https://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/c47udvcbil130kl90cm2fo9048","2014-09-10 14:50:22","2014-10-21 21:12:48"
"2551","46","The Vietoris-Rips Complex of the Circle","2014-09-18 15:00:00","2014-09-18 16:00:00","SAS 4201","Henry Adams","http://www.math.duke.edu/~hadams/","Duke University","Irina Kogan",,"Given a metric space and a positive connectivity parameter, the Vietoris-Rips simplicial complex has a vertex for each point in the metric space, and contains a set of vertices as a simplex if its diameter is less than the connectivity parameter. A theorem of Jean-Claude Hausmann states that if the metric space is a Riemannian manifold and the connectivity parameter is sufficiently small, then the Vietoris-Rips complex is homotopy equivalent to the original manifold. What happens as we increase the connectivity parameter? We show that the Vietoris-Rips complex of the circle obtains the homotopy type of the circle, the 3-sphere, the 5-sphere, the 7-sphere, ..., until finally it is contractible. It remains an open problem to describe the Vietoris-Rips complexes of higher-dimensional spheres as the connectivity parameter increases. As motivation for our work, we note that Vietoris-Rips complexes are commonly used in topological data analysis, and hence it is important to understand their behavior on simple spaces such as the circle. Joint work with Michal Adamaszek, Florian Frick, Christopher Peterson, and Corrine Previte.","aacoope2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/g67226h2qrgkakic795k4pitv4","2014-09-10 23:05:14",NULL
"2554","4","Evans function computation and the stability of traveling waves","2015-03-30 15:00:00","2015-03-30 16:00:00","SAS 2102","Jeff Humpherys","http://www.math.byu.edu/~jeffh/","Brigham Young University","Steve Schecter",,"We discuss the Evans function and its usefulness in the study of traveling wave stability.  We give a historical overview of the computational methods used to compute the Evans function, together with a discussion of the challenges and pitfalls that can arise and how to overcome them.  The Evans function is most useful when combined with analytical methods.  We show a few examples where this combination has been very successful.  This talk will be accessible to advanced undergrads and graduate students.","schecter","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/m01lj1sh7no0idmisa1i0crp7k","2014-09-12 14:46:24","2015-03-24 14:06:14"
"2557","3","Deformation quantization: obstructions to existence and graph complexes","2014-09-29 14:30:00","2014-09-29 15:30:00","SAS 4201","Vladimir Baranovsky","http://www.math.uci.edu/~vbaranov/","University of California Irvine",,,"We explain older and recent results concerning existence of quantization of algebraic symplectic manifolds. We are interested in two questions: when can we quantize regular functions on a smooth algebraic symplectic variety, and if that is possible, when can a module over regular functions be quantized as well. We also outline some expected relation between obstructions to such existence, and the graph complex. Joint work with V. Ginzburg, D. Kaledin and J. Pecharich.","bnbakalo","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/21oj2r3gbo9dos4nhglvkjpiks","2014-09-15 08:38:55",NULL
"2560","4","Geometric phase in the Hopf bundle and the stability of nonlinear waves","2014-10-06 15:00:00","2014-10-06 16:00:00","SAS 2102","Colin Grudzien","http://cgrudz.web.unc.edu","University of North Carolina at Chapel HIll","Steve Schecter",,"Evans function analysis has become a standard method of calculating the stability of nonlinear waves for PDEs.  Building on the machinery of the Evans function, we have proven the validity of a related, alternative form of analysis that uses the Hopf bundle, whose total space is S^{2n-1}.  This bundle is naturally imbedded in complex n-space and is locally the product of a circle and a neighborhood in CP^{n-1}.  The dynamical system associated with the linearized operator for a PDE induces a winding number through parallel transport in the fibre. Our method uses parallel transport to count the multiplicity of eigenvalues contained within a loop in the spectral plane.","schecter","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gh8s3c08pi4p31viplpktn9pj8","2014-09-15 10:12:28","2014-09-19 14:58:14"
"2566","19","Toric Ideals and Transportation Problems","2014-09-17 15:00:00","2014-09-17 16:00:00","Riddick Hall 450","Daniel Bernstein",,,,,,"esbarnar","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/afg3u23qvpfajqfnpu4ir07oeg","2014-09-15 11:11:48",NULL
"2569","14","Applied Math Colloquium Tea","2014-09-16 16:00:00","2014-09-16 16:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/r0qggqi9m2e9lj0vfv9j0m92p8","2014-09-16 09:47:38","2014-09-16 09:50:31"
"2572","3","Realization of certain modules for affine and superconformal vertex algebras","2014-10-06 14:30:00","2014-10-06 15:30:00","SAS 4201","Drazen Adamovic","http://web.math.pmf.unizg.hr/~adamovic/","University of Zagreb, Croatia",,,"We shall first review a correspondence between affine vertex algebras associated to A_1 ^(1) and N=2 superconformal vertex algebras. In the limit, this correspondence can be used for the study of irreducible modules for the affine Lie algebra sl_2^ at the critical level.  We shall partially extend this construction to a higher rank case, and find a connection between the simple N=4 vertex algebra and the affine Lie algebra A_2^(1)}. Explicit realization of certain families of irreducible modules will be discussed. Our construction is related to certain vertex algebras appearing in logarithmic conformal field theory.","bnbakalo","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ais3vb073ucd2l734t5nqojj80","2014-09-16 14:24:54","2014-09-29 19:10:19"
"2575","5","Supersymmetry and Witten index","2014-09-19 15:00:00","2014-09-19 16:00:00","SAS 2102","Jining Gao",,,,,"What is supersymmetry(SUSY) ?&quot; by introducing an illustrative toy model,then I will define Witten index and show its just Euler character when we reformulate Hodge theory in supersymmetry model.","bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3hof40c4qj2stcrg24cs4q66i0","2014-09-16 15:10:37","2014-09-17 10:11:33"
"2578","4","Wavespeed selection and anomalous spreading in systems of reaction-diffusion equations","2014-10-27 15:00:00","2014-10-27 16:00:00","SAS 2102","Matt Holzer","http://math.gmu.edu/~mholzer","George Mason University","Steve Schecter",,"Wavespeed selection refers to the problem of determining the long time asymptotic speed of invasion of an unstable homogeneous state by some other secondary state. This talk will review wavespeed selection mechanisms in the context of reaction-diffusion equations. Particular emphasis will be placed on the qualitative differences between wavespeed selection in systems of reaction-diffusion equations and scalar problems as well as some surprising consequences. The primary example will be a system of coupled Fisher-KPP equations that exhibit anomalous spreading wherein the coupling of two equations leads to faster spreading speeds.  This phenomena is related to the existence of poles of the pointwise Greens function.","schecter","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3c5vffpjhehjruaharsi95cqo0","2014-09-17 09:37:28","2014-10-20 10:04:48"
"2581","27","Triangle Lectures in Combinatorics","2014-10-04 09:15:00","2014-10-04 17:00:00","High Point University in High Point, NC",,,,,"http://www.math.ncsu.edu/TLC/","The Triangle Lectures in Combinatorics is a series of combinatorial workshops held each semester on a Saturday in the Research Triangle region of North Carolina, funded by the National Security Agency and the National Science Foundation.  The workshop this fall will be hosted by High Point University in High Point, North Carolina on October 4, 2014.  It will include four one hour invited talks as well as coffee breaks and ample time for discussions throughout the day.  There will also be two related seminar talks on Friday afternoon just prior to the meeting.","bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/lbgore65r06g4oes0daj5eu7j0","2014-09-17 12:04:48",NULL
"2587","46","Obstructions to Compatible Extensions of Mappings","2014-05-25 15:00:00","2014-05-25 16:00:00","SAS 4201","Jose Perea","https://fds.duke.edu/db/aas/math/joperea","Duke University","Radmila Sazdanovic",,"Several classic invariants in algebraic topology (e.g. Stiefel-Whitney classes) can be phrased in terms of being able to extend, or lift, certain mappings. We will report in this talk ongoing efforts toward making these tools available in the world of topological data analysis.","aacoope2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7aj8gpmeckl8dt7gdeqiqk85rc","2014-09-19 19:53:34",NULL
"2590","46","Obstructions to Compatible Extensions of Mappings","2014-09-25 15:00:00","2014-09-25 15:00:00","SAS 4201","Jose Perea","https://fds.duke.edu/db/aas/math/joperea","Duke University","Radmila Sazdanovic",,"Several classic invariants in algebraic topology (e.g. Stiefel-Whitney classes) can be phrased in terms of being able to extend, or lift, certain mappings. We will report in this talk ongoing efforts toward making these tools available in the world of topological data analysis.","aacoope2","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eesq2f98o4oaf84kr54bm690qo","2014-09-19 19:56:10",NULL
"2593","23","Preparing your CV, Teaching &amp; Research Statements","2014-09-26 15:00:00","2014-09-26 16:00:00","SAS 4201","Math Department Faculty",,"NC State","Mansoor Haider",,"This seminar is targeted at graduate students who will be on the academic job market this year or in the near future. After a short presentation on some helpful resources for your job search, well have Q&amp;A with a few faculty members on how to best prepare your application materials.","mahaider","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/sc05vim82resjpnislfhjjr5g0","2014-09-22 10:58:27",NULL
"2596","19","Cluster Algebras","2014-09-24 15:00:00","2014-09-24 16:00:00","SAS 3282","Salvatore Stella","http://www4.ncsu.edu/~sstella/",,,,,"esbarnar","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/v0veqc2oenu6ku5q41japabofg","2014-09-22 13:21:41",NULL
"2599","19",,"2014-10-01 15:00:00","2014-10-01 16:00:00","SAS 3282","Emily Meehan",,,,,,"esbarnar","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5lv0oopflk4g1rmn8jtloa1f7c","2014-09-22 13:23:27",NULL
"2602","19",,"2014-10-15 15:00:00","2014-10-15 16:00:00","SAS 3282","Mark Hunnell","http://www4.ncsu.edu/~mchunne2/",,,,,"esbarnar","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/cd2f3pkrtt2h88okh538vkbh8k","2014-09-22 13:24:48",NULL
"2605","9","Quantifying secretion in the embryonic lung and its implication for morphogenesis","2014-09-30 16:15:00","2014-09-30 17:15:00","Cox 306","Uduak George",,"NC State Department of Mathematics",,,"Experimental studies have led to the identification of genes and morphogens that regulate lung morphogenesis. However, the mechanism by which these signaling molecules regulate lung morphogenesis is not fully understood. Until birth, the lung is filled with liquid. This lung liquid is vital for lung development and growth. Reduction in the volume of lung liquid causes lung hypoplasia while an increase in lung liquid distension leads to an increase in lung growth. In this study, we develop a computational model of an embryonic lung to study the effect of lung liquid distension on lung development. We use Darcys law to model the transport of lung liquid in the porous region of the embryonic lung and Stokes flow to model the transport of lung liquid in the luminal region of the embryonic lung. By coupling these two models to an advection-diffusion equation that describes the transport of genetic materials, we are able to study the effect of lung liquid distension on the transport of key signaling molecules for example fibroblast growth factor. In this study, we show that liquid distended lungs could increase lung growth by influencing the distribution of signaling molecules.","allloyd","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/20vrll3ka3e5ne8ta5v32mmqdk","2014-09-24 09:19:06",NULL
"2608","9","Where to protect? Dragonfly metapopulation &amp; metacommunity analyses for conservation planning","2014-10-02 16:15:00","2014-10-02 17:15:00","Cox 306","Takehiko Yamanaka",,"National Institute for AgroEnvironmental Sciences, Japan ",,,,"allloyd","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5kti1sbe7s12hkgjmcglt48bk0","2014-09-24 09:21:17",NULL
"2611","14","Departmental Tea and Cookies","2014-09-24 14:30:00","2014-09-24 15:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/dqd463bdi92tm4olj04u81ghag","2014-09-24 11:24:27",NULL
"2614","14","Departmental Tea and Cookies","2014-09-30 16:00:00","2014-09-30 16:30:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gn65qqiebn6bipfthavjiln974","2014-09-24 11:24:53","2014-09-26 12:13:05"
"2617","14","Departmental Tea and Cookies","2014-10-22 14:30:00","2014-10-22 15:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2qeo26t0osamac6j559qejiqco","2014-09-24 11:25:17",NULL
"2620","14","Departmental Tea and Cookies","2014-10-28 16:00:00","2014-10-28 16:30:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/s27uuoqp4b0ghg824qv3k25g6o","2014-09-24 11:25:41","2014-10-27 10:37:16"
"2623","14","Departmental Tea and Cookies","2014-11-12 14:30:00","2014-11-12 15:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qej9lbc3f62evpo4tn6pcb06do","2014-09-24 11:26:05",NULL
"2626","14","Departmental Tea and Cookies","2014-11-17 16:00:00","2014-11-17 16:30:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/bbokei76kilhircf5a2kf3ti20","2014-09-24 11:26:28","2014-11-17 09:52:59"
"2629","14","Departmental Tea and Cookies","2014-12-03 14:30:00","2014-12-03 15:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/i4tm5kd8hikr51m9292pd6l01s","2014-09-24 11:27:00",NULL
"2632","14","Departmental Tea and Cookies","2014-10-16 15:30:00","2014-10-16 16:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/qvmil540monple3061qou32n48","2014-09-24 11:28:03","2014-09-24 11:28:22"
"2635","14","Departmental Tea and Cookies","2014-11-05 15:30:00","2014-11-05 16:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/6701q0smpc3rvpisibilqe2upc","2014-09-24 11:28:59","2014-09-24 11:30:04"
"2638","38","Mathematical and Computational Mixture Models for Cartilage Regeneration in Cell-Seeded Scaffolds - advised by Mansoor Haider","2014-10-02 10:00:00","2014-10-02 11:30:00","SAS 3282","Ahlam Elashegh",,"NC State",,,,"mahaider","0",,"2014-09-25 13:13:08","2014-09-25 13:14:19"
"2639","28","AWM Brown Bag Lunch","2014-09-30 12:00:00","2014-09-30 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/flfc303mu53bkkqe3mi6a79n94","2014-09-29 14:28:00",NULL
"2642","28","AWM Brown Bag Lunch","2014-10-07 12:00:00","2014-10-07 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/63783fol2s48amuo2gu4f7qars","2014-09-29 14:28:46",NULL
"2645","28","AWM Brown Bag Lunch","2014-10-14 12:00:00","2014-10-14 13:00:00","4th floor commons",,,,,,,"cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8s9csjhi75u0t1auj2mhhukgn4","2014-09-29 14:29:08",NULL
"2648","28","AWM Brown Bag Lunch","2014-10-21 12:00:00","2014-10-21 13:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/g5srasrl1acimqtg06j8pfg434","2014-09-29 14:29:28","2014-10-21 10:09:24"
"2651","28","AWM Brown Bag Lunch","2014-10-28 12:00:00","2014-10-28 13:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/vkpo9r5lf11sdtqjijile1h5es","2014-09-29 14:29:48","2014-10-21 10:09:38"
"2654","46","Super Lie groups of conventional super Lie algebras Part I","2014-10-02 15:00:00","2014-10-02 16:00:00","SAS 4201","Ronald Fulp",,"NC State",,,"My first lecture on Thursday is intended as an introduction to $G^{\infty}$ supermanifolds and should be accessible to a general audience. I intend to sketch a proof of a generalization of a Theorem of Rogers which demonstrates how to obtain a super Lie group from a conventional super Lie algebra. Such super Lie algebras are defined to be $\Lambda \otimes g$ where $\Lambda$ denotes the Grassmann algebra of super numbers and $g$ is a $Z_2$ graded Lie algebra. My second lecture requires this theorem in order to show that the group of local isometries of a super Riemannian metric is a super Lie group. I want to know how to obtain super spinors in this context.","iakogan","1","https://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/0ndrspdba1irfcm6vp82ick3ck","2014-09-30 14:59:16","2014-10-02 10:52:27"
"2658","15","SIAM Meeting and Pizza","2014-10-15 12:20:00","2014-10-15 13:15:00","Riddick 450","Corey Winton",,"US Army Corps of Engineers",,,"Dr. Corey Winton is a research mathematician for the US Army Corps of Engineers. He received his PhD at NCSU under advisor Tim Kelley in 2012. He will be talking about several projects that he has worked on including: 

--- Lake Superior Modeling - USACE is tasked with forecasting the depth of all the Great Lakes.  We analyzed the model to determine if there were any seasonal biases and analyzed the optimal number of parameters to use in the model.
 --- Supply Chain Network Analysis - Part of the Corps duties is to aid decision makers in determining optimal locations for bases / airports / seaports and the network that connects them.  
 --- Resource Allocation for Dredging - USACE must maintain the shipping channels throughout the nation to ensure adequate transfer of goods along the waterways.  Unfortunately, there simply is not enough funds to maintain every port and channel at the ideal depth requested by the shipping captains.  We investigate how to apply funds to maximize the tonnage that will pass through the system over multiple years using a genetic algorithm to inform the decision process.

Lunch will be provided and everyone is welcome!","mestrait","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/an1jjvqa014tb5bqi0sno11t28","2014-10-06 13:19:09","2014-10-07 08:31:30"
"2661","28","AWM Bake Sale","2014-10-15 10:00:00","2014-10-15 15:00:00","SAS Atrium",,,,,,"Baked goods will be available to purchase and make your Wednesday just a little sweeter!","cbattis2","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/ciso05grg5s25q8ieu3na11k80","2014-10-06 18:51:27",NULL
"2664","14","Departmental Tea and Cookies","2014-10-08 14:30:00","2014-10-08 15:00:00","SAS 4104",,,,,,,"bennett","1","https://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1bkiq2p0qadhr4mraq6vu3ugt0","2014-10-07 09:57:39",NULL
"2667","46","Spin groups of super metrics","2014-10-23 15:00:00","2014-10-23 16:00:00","SAS  4201","Ronald Fulp","http://www4.ncsu.edu/~fulp/","NC State",,,"We generalize the notion of a Riemannian metric so that it acts on super vector fields. This generalization is called a super Riemannian metric. In the simplest case the canonical form of such a metric is an orthosymplectic matrix which I will define in the lecture. We discuss the general case and some of the issues involved. My interest, though not fully realized, is to understand how super spinor fields arise in this context. I determine the super Lie group of local isometries of a super metric. I will show how super spinor fields are determined by representations of this super Lie group.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/saqkudk8pd0kqpomlbvv9msnlc","2014-10-08 14:19:09",NULL
"2670","26","TBA","2014-10-27 16:00:00","2014-10-27 17:00:00","SAS 4104","Melissa Strait",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fu7qpk231pj6suseso20h10r7c","2014-10-09 13:20:45","2014-10-15 12:02:47"
"2673","26","Computational model for optical coherence tomography imaging of the human eye","2014-11-03 16:00:00","2014-11-03 17:00:00","SAS 4104","Micaela Mendlow",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/eukufkest188iajis81qgrq3v4","2014-10-09 13:21:28","2014-11-03 14:58:46"
"2676","26","TBA","2014-11-10 16:00:00","2014-11-10 17:00:00","SAS 4104","Kristen Tillman",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l06lml1l3khl6o4jiti57th69g","2014-10-09 13:22:06",NULL
"2679","26","TBA","2014-11-17 16:00:00","2014-11-17 17:00:00","SAS 4201","Elisabeth Brown",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/58vlpdkto6c9nncsb9u1t88g1g","2014-10-09 13:22:43","2014-11-17 10:41:52"
"2682","26","TBA","2014-11-24 16:00:00","2014-11-24 17:00:00","SAS 4104","Katie Schmidt",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/986o9i74jjpivosvi04lrilofo","2014-10-09 13:23:33",NULL
"2694","43","Stories of Traffic Models, Phantom Jams, Jamitons, and Autonomous Vehicles","2014-11-17 15:00:00","2014-11-17 15:50:00","SAS 2102","Benjamin Seibold","http://www.math.temple.edu/~seibold/","Temple","Pierre Gremaud",,"Initially homogeneous vehicular traffic flow can become inhomogeneous
even in the absence of obstacles. We demonstrate how this phenomenon,
called a phantom traffic jam, can be described via traffic models.
Employing a macroscopic (i.e. fluid-dynamical) description of traffic
flow, phantom jams are shown to arise as instabilities in which small
perturbations amplify and grow into nonlinear traveling waves, called
jamitons. These jamitons turn out to be analogs of detonation
waves in reacting gas dynamics, thus creating an interesting link
between traffic flow, combustion, water roll waves, and black holes.
We furthermore demonstrate that jamitons can serve as an explanation
for the multi-valued nature that fundamental diagrams of traffic flow
are observed to exhibit, and provide insights to the fidelity of
data-fitted macroscopic traffic models. Finally, an outlook is given
on how these traffic models can provide strategies to control
autonomous vehicles so that the fuel consumption of the overall
traffic flow is reduced.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk%40group.calendar.google.com/private/full/3flb186a0mhadpagtl2tt4tftk","2014-10-10 11:20:36","2014-11-06 09:12:13"
"2696","9","A Mathematical Model of Glutamate and Glutamine Metabolism in the Rat: Implications for Catabolic Illness and Acetaminophen Overdose","2014-10-14 16:15:00","2014-10-14 17:15:00","Cox 308","Lydia Bilinsky",,"Duke University, Mathematics",,,"Abstract: The liver is the major site of amino acid metabolism, and the organ in which most glutathione (GSH) synthesis occurs; GSH has been referred to as the &quot;master antioxidant&quot; and has a major role in protection against oxidative stress and removal of xenobiotics. Glutamate is one of the three amino acid precursors of GSH and also serves as an intermediary for the disposal of dietary amino groups via urea. When there is an increased need for glucose, glutamate can be converted to alpha-ketoglutarate, a TCA cycle intermediate that can be used as a substrate for gluconeogenesis. Most liver cells cannot take up glutamate in blood plasma and instead synthesize it from plasma glutamine. Many pathological conditions are characterized by a catabolic state in the body, in which there is an increased breakdown of skeletal muscle protein, an increased release of glutamine into plasma, and an increased rate of gluconeogenesis in liver. We have developed a mathematical model of glutamate and glutamine metabolism which features both liver and skeletal muscle and have used it to explain a number of experimental findings for glucocorticoid-induced catabolic states. The model also provides insight into why glutamine supplementation protects GSH stores during acetaminophen overdose, when cysteine is usually the rate-limiting precursor.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7l76392lf8tnr7vptltn0a4ak8","2014-10-13 14:04:20",NULL
"2698","38","Frattini Properties of Leibniz Algebras - advised by Ernie Stitzinger","2014-11-14 15:00:00","2014-11-14 16:30:00","SAS 2102","Alison McAlister",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c%40group.calendar.google.com/private/full/7ngt9odppdda5hb1hj3c5sij00","2014-10-13 15:05:10",NULL
"2700","21","Virginia Tech Regional Math Contest","2014-10-25 09:00:00","2014-10-25 11:00:00","SAS 4201",,,,,,"Our undergraduate students in NCSU can participate in the  Virginia Tech Regional Math contest.
If you teach undergraduate courses, please tell your students this years competition  takes place on Saturday October 25, 9-11:30a.m.  Walk in registration is available. If anyone is interested, please contact Prof. Lin by email:
xblin@ncsu.edu","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/krh3ks622k315mg7p4o0v8s868","2014-10-14 09:35:57","2014-10-21 10:10:11"
"2702","9","A computational study of pressure wave reflections in the pulmonary arteries and the significance of longitudinal position for estimating the pulse wave velocity for wave separation","2014-10-21 16:15:00","2014-10-21 17:15:00","Cox 306","Muhammad Qureshi",,"NC State Department of Mathematics",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ghbpi97tp7mpkqrs50qda39i68","2014-10-16 10:17:02","2014-10-16 10:20:46"
"2703","9","Multiphysics and multiscale modeling of cardiac dynamics","2014-10-28 16:15:00","2014-10-28 17:15:00","Cox 306","Boyce Griffith",,"Mathematics Department, UNC Chapel Hill",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2gl7vr02nr8e696cs5pv338rtg","2014-10-16 10:18:49","2014-10-16 10:21:42"
"2704","9","Modeling tuberculosis, from cells to populations","2014-11-04 16:15:00","2014-11-04 17:15:00","Cox 306","Leonid Chindelevitch",,"Harvard School of Public Health",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/o111a41jpemfrgsu1r9chuqjmg","2014-10-16 10:24:32",NULL
"2705","9","A Multi-Generational Basic Reproductive Number in a Heterogeneous Epidemiological Community Model","2014-11-11 16:15:00","2014-11-11 17:15:00","Cox 306","Isaac Michaud",,"NC State, Department of Statistics",,,"The basic reproductive number is a number which estimates the infectiousness of a disease and is used by epidemiologists to measure the efficacy of disease control measures. Intuitively, this number is defined as the expected number of infectious cases generated from a single infectious individual in an otherwise uninfected population. The connection between this definition and the reproductive numbers formal definition is clear when a diseases model is simple, but becomes opaque as the models complexity increases. An extension of the intuitive reproductive number, which focuses on secondary and tertiary generations of infections, is used to study the likelihood of an outbreak in a community structured population which incorporates varying vaccination rates among communities. Connections are drawn between this multi-generation reproductive number and the formal definition of the basic reproductive number and a few interesting situations will be shared where differently defined reproductive numbers disagree about the qualitative dynamics of the presented model.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/2fb507ahthif11i11u8aafvq98","2014-10-16 10:27:13","2014-11-02 10:10:34"
"2706","9","Integrating Contemporary Tools in Botanical Epidemiology: A Case Study","2014-11-18 16:15:00","2014-11-18 17:15:00","Cox 306","Peter Ojiambo",,"NC State, Department of Plant Pathology",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/k0229kufnrdquaiojbss04dp88","2014-10-16 10:31:20","2014-11-11 09:21:15"
"2707","9","Modeling the oscillations of the Hypothalamic-Pituitary-Adrenal axis","2014-12-02 16:15:00","2014-12-02 17:15:00","Cox 306","Johanne Gudmand-Hoyer",,"Roskilde University",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/kldodl9kqdm6t378ctovsm83b0","2014-10-16 10:32:40",NULL
"2708","4","Hamels Formalism for Classical Field Theories and the Dynamics of the ChaplyginTimoshenko Sleigh","2014-10-29 15:00:00","2014-10-29 16:00:00","SAS 4201","Donghua Shi",,"Beijing Institute of Technology",,,"In Hamels formalism of classical finite-dimensional mechanics, unlinking the configuration and velocity measurements often results in a simpler representation of equations of motion. In this talk, these ideas will be extended to the classical field theory setting. I will first introduce Hamiltons principle for Hamels field equations that unify the spatial and convective representations in continuum mechanics. Applications to systems with symmetry and constraints will follow. Finally, the dynamics of a flexible beam sliding on ice will be presented to illustrate the usefulness of the formalism.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/5u7anfgi1lvrqgt691rtqpq31k","2014-10-17 09:52:21",NULL
"2709","6","A high-order discontinuous Galerkin scheme for entropy-based moment closures of linear kinetic equations","2014-10-22 16:00:00","2014-10-22 16:50:00","SAS 4201","Graham Alldredge","http://www.mathcces.rwth-aachen.de/5people/alldredge/start","RWTH Aachen University","Pierre Gremaud",,"Entropy-based moment closures for kinetic equations have particularly attractive theoretical properties, including hyperbolicity, positivity, and entropy dissipation, but there remain many obstacles to a practical implementation, particularly one which is high-order.  A primary obstacle is that although the method is only defined for realizable moments (those consistent with a positive distribution), nonrealizable moments arise due to numerical errors,   We have implemented a third-order solver, using the Runge-Kutta discontinuous Galerkin method, with a limiter which takes nonrealizable moments back into the realizable set.  Instead of the exact realizable set, whose description is intractably complex, we use the realizable set generated when the defining integrals are approximated by quadrature.  This set is a convex polytope, and using its half-space representation we are able to compute the intersection of the polytope and a line.  We present numerical results including a convergence test and benchmark problems.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/p4ber7pbrgrgrbbff1fpv34c9c","2014-10-20 10:15:25",NULL
"2711","5","Supersymmetry approach to Atiyah-Singer index theorem for Dirac operators","2014-10-24 15:00:00","2014-10-24 16:00:00","SAS 2102","Jining Gao",,,,,"There are two different fashions to prove Atiyah-Singer index theorem, the old one is just from topological K theory, and the &quot;new&quot; one is  so called heat kernel method. Actually, the &quot;new&quot; one arrised from supersymmetry method in physics.
 In this lecture I will  present how the supersymmetry method works in the proof of  A-S index theorem. First of all Im going to  represent Dirac index in term of path integral for supersymmetric  non-linear sigma model on any spin manifolds, and then supersymmetry principle can help us to reduce any such path integrals to the integrals around  constant  modes, and  spin genus will appear amazingly after a quick computation.
All preliminary about spin manifolds and Dirac operators will also be introduced at  the beginning of the lecture.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/f25l157q192q161o5pl3f2nms0","2014-10-20 10:16:46",NULL
"2713","10","A cutting surface algorithm for semi-infinite convex programming and moment robust optimization","2014-10-21 16:30:00","2014-10-21 17:30:00","Daniels 434","David Papp",,,,,"Results of stochastic optimization problems where data
uncertainty is modeled with an incorrectly specified distribution can
be misleading. Recently it has become a popular approach to model
stochastic optimization problems as robust stochastic programs, where
the stochastic optimization is against an adversarial distribution. In
this talk, after an introduction to this area, we will present a novel
algorithm for the solution of robust stochastic optimization problems
where the only distributional assumptions on the uncertain data are
that the moments of the distribution are within known bounds. The
solution method has two novel components, both of which might be of
independent interest. The first ingredient is a new algorithm for the
solution of convex optimization problems with infinitely many,
possibly non-smooth, constraints indexed by an infinite-dimensional
set. Our second ingredient is an algorithm to find a discrete
probability distribution that optimizes a given linear functional
subject to bound constraints on its moments.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/romd1pn5uismtlhr6fmlea36mk","2014-10-20 12:36:26","2014-10-20 12:39:52"
"2715","3","Moduli spaces for Schur-tame algebras","2014-10-27 14:30:00","2014-10-27 15:30:00","SAS 4201","Andrew T. Carroll",,"DePaul University","Salvatore Stella",,"Over the last 40 years there have been a number of attempts to characterize the complexity of the category of modules over a (finite-dimensional associative) algebra by means of invariant theory.  More precisely, we seek to determine whether an algebra is tame or wild (in the sense of Drozds Dichotomy Theorem) by considering (1) rings of invariant functions and (2) the geometry of their moduli spaces.  Such characterizations have been demonstrated in the context of path algebras of quivers, but attempts to generalize to bound quiver algebras have met resistance.  A more reasonable request is that the invariant theory should capture the behavior of the Schur modules over an algebra.  In this talk, I will define the notion of Schur representation type, introduce some examples of algebras that are wild but Schur-tame, and illustrate a partial characterization of Schur representation type via invariant theory.  This is joint work with Calin Chindris.","sstella","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/fcn9suml3r7bhd8l7u1onj9r0c","2014-10-20 21:03:31","2014-10-20 21:05:21"
"2717","8","A Modern Software Architecture for Mathematical Collaboration","2014-11-14 14:00:00","2014-11-14 15:00:00","Park Shops 201","Stephen M. Watt",,,"Erich Kaltofen",,"We present the elements of a new architecture for computer-assisted mathematical collaboration based on a shared virtual canvas. Free-hand pen input, geometric sketches, typed input and images can be entered and viewed simultaneously by multiple participants. In particular, this allows the shared entry and manipulation of mathematics and the annotation of documents. Pen input is captured as InkML, rather than as raster graphics, allowing semantic analysis and manipulation. Unlike previous work, we make the communications layer fundamental and base composition and editing functions on top of that, instead of viewing communication as an add-on to a drawing program. Based on our past experience, we have chosen this time to make ease of casual use and adoption the principal design criterion. This has led to a JavaScript browser implementation and cloud-based storage.","kaltofen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/va2dftt6nk8ve35otvjvvt2228","2014-10-21 12:32:21","2014-11-07 15:13:00"
"2719","3","Fano orbifold curves and integrable hierarchies","2014-11-03 14:30:00","2014-11-03 15:30:00","SAS 4201","Todor Milanov","http://member.ipmu.jp/todor.milanov/","Institute for the Physics and Mathematics of the Universe, Japan",,,"I will talk about my recent joint work with Hsian-Hua Tseng and Yefeng Shen where we prove that the orbifold GW invariants of a Fano orbifold curve are governed by an appropriate Kac-Wakimoto hierarchy. Fano orbifold curves are parametrized by ADE Dynkin diagrams with a choice of a branching node, while the Kac-Wakimoto hierarchy is constructed by an appropriate Fock space realization of the basic representation of the corresponding affine Lie algebra. My goal is to explain how the representation can be constructed in terms of the geometry of the orbifold curve.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/hak6qia9rgl4kqff2b2cspho5k","2014-10-22 10:10:19",NULL
"2721","3","Ribbon biquandles and knotted surfaces","2014-11-10 14:30:00","2014-11-10 15:30:00","SAS 4201","Sam Nelson","http://www.esotericka.org/cmc/","Claremont McKenna College",,,"Knotted surfaces can be represented with diagrams known as ch-diagrams where two diagrams represent ambient isotopic knotted surfaces iff they are related by a sequence of Yoshikawa moves. Recently Kauffman introduced a generalization of knotted surfaces by adding virtual crossings to ch-diagrams. In this talk we will define invariants of knotted and virtual knotted surfaces using algebraic objects known as ribbon biquandles.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ir3gc5raslibabgft3m18vtukc","2014-10-22 10:14:02",NULL
"2723","11","Quantitative Finance - A Multidisciplinary Approach","2014-10-24 13:30:00","2014-10-24 14:30:00","SAS 2225","Dr. Robert Darwin",,"QMS Capital",,,"Guests are welcome, but seating is limited.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/8fh5lk3t06j9n79qricpq7hmcs","2014-10-23 10:01:35",NULL
"2728","2","Opportunities at the Laboratory for Analytic Sciences","2014-11-12 15:00:00","2014-11-12 16:00:00","SAS 4201","Dr. James Keiser ",,"Laboratory for Analytic Sciences","Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/25j6u5hh2s75ddb1pk6rh2jq44","2014-10-27 13:29:56","2014-10-28 16:22:23"
"2730","28","AWM Brown Bag Lunch","2014-11-04 12:00:00","2014-11-04 13:00:00","4th floor commons",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/2dqjk6p81gn9lo1eccibdb0260","2014-10-27 20:16:05",NULL
"2732","28","AWM Brown Bag Lunch","2014-11-11 12:00:00","2014-11-11 13:00:00","4th floor commons",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/1vaj0msqif24q88f642clu0uvg","2014-10-27 20:16:36",NULL
"2734","28","AWM Brown Bag Lunch","2014-11-18 12:00:00","2014-11-18 13:00:00","4th floor commons",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/id94cdqd92ofcfg6st4t7oilfo","2014-10-27 20:17:05",NULL
"2736","28","AWM Brown Bag Lunch","2014-11-25 12:00:00","2014-11-25 13:00:00","4th floor commons",,,,,,,"dmhaught","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/8v8rrl26ivu2e9na70i7anvva4","2014-10-27 20:17:28","2014-11-19 13:31:12"
"2738","28","AWM Brown Bag Lunch","2014-12-02 12:00:00","2014-12-02 13:00:00","4th floor commons",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/g1dqbi1o4kq42rpbn4ca3n9efo","2014-10-27 20:18:00","2014-10-27 20:19:34"
"2740","11","A Series of Panel Discussions For Students  Interested in a Career in Quantitative Finance","2014-11-14 17:00:00","2014-11-14 20:00:00","SAS Atrium","Jared Bogacki, Jeff Rockwell High, Albert Hopping, James Russo, and Jeff Scroggs",,,,"http://iaqf16.wildapricot.org/widget/event-1753868","Please register at http://iaqf16.wildapricot.org/widget/event-1753868

5:00pm Registration 
5:30pm Program Begins
6:30pm Reception &amp; Networking","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ppb1liue0npb4iijsuoftrbn3k","2014-10-28 10:59:16","2014-11-11 09:33:30"
"2742","46","Introduction to Operads, Part 2","2014-10-30 15:00:00","2014-10-30 16:00:00","SAS 4201","Tom Lada",,"NC State",,,"I will review the definition of operads and present several more examples and applications.  In particular, i will sketch the transition from their role in encoding iterated loop space data topology to describing the structures of a variety of algebras.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/7ujaq55lv98fnrrn7c3clmt4vc","2014-10-29 03:52:16",NULL
"2744","4","From crime waves to segregation: what we can learn from basic PDE models","2014-12-03 15:00:00","2014-12-03 16:00:00","SAS 4201","Nancy Rodriguez-Bunn","http://nrodriguez.web.unc.edu/","UNC at Chapel Hill","Lorena Bociu",,"The use of PDE models to describe complex systems in the social sciences, such as socio-economic segregation and crime, has been popularized during the past decade.  In this talk I will introduce some PDE models which can be seen as basic models for a variety of social phenomena.  I will then discuss how these models can be used to explore and gain understanding of the real-world systems they describe.  For example, we learn that a populations innate views toward criminal activity can play a significant role in the prevention of crime-wave propagation.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/a727j87sl9un70b04n5f3tkseo","2014-10-29 11:23:15","2014-11-24 21:30:21"
"2746","46","The Turaev surface, ribbon graphs, and Khovanov homology","2014-11-06 15:00:00","2014-11-06 16:00:00","SAS 4201","Adam Lowrance","http://faculty.vassar.edu/adlowrance/","Vassar College","Radmila Sazdanovic",,"In 1987, Turaev gave an alternate proof to Murasugi and Kauffmans theorem stating that the span of the Jones polynomial gives a lower bound on the crossing number of a link. In Turaevs proof, he associates to each link diagram a certain Heegaard surface in S^3, now known as the Turaev surface of the diagram. In this talk, we show that the Khovanov homology of a link can be modeled with ribbon graphs embedded in the Turaev surface. We also show how certain gradings in Khovanov homology are seen by the topology of the Turaev surface.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ojkeq00l7mmoo88jjdq41r6u6s","2014-10-29 12:28:21",NULL
"2748","11","GARP Chapter Meeting - Do Hedge Funds Exploit Rare Disaster Concerns?","2014-11-24 18:30:00","2014-11-24 21:00:00","SAS 4201","Dr. George P. Gao","http://www.garp.org/membership/ChapterMeetings/Downloads/Gao_George-BIO.html","Johnson Graduate School of Management, Cornell University","GARP, Join as an affiliate for free",,"We investigate whether hedge fund managers with better skills of exploiting the markets ex ante rare disaster concerns, which may not realize as disaster shocks ex post, deliver superior future fund performance. We measure fund skills in exploiting rare disaster concerns (SED) using the co-variation between fund returns and a disaster concern index we develop through out-of-the-money puts on various economic sector indices. Funds earning higher returns when the index is high possess better skills of exploiting disaster concerns. Our main result shows that high-SED funds on average outperform low-SED funds by 0.96% per month and even more during stressful market times, while high-SED funds have less exposure to disaster risk.

Pre-registration strongly suggested.  Browse to https://www.garp.org/events/chapter-meetings/cm-login.aspx?selMId=1374","scroggs","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/ic9geut3rbt547m1didlhioocc","2014-10-30 09:19:40",NULL
"2750","21","The Kwangil Koh Lecture on Mathematics in Our Time","2015-04-14 16:00:00","2015-04-14 17:30:00","SAS 2203","Frank Morgan",,,,"http://www.math.ncsu.edu/events/Morgan.php","Professor Morgan  will address how soap bubbles continue to confound and amaze mathematicians - they are a serious topic in mathematics, and one with lots of applications. Interestingly, some recent mathematical breakthroughs in this area have actually come from students.  The lecture will include demonstrations, explanations, and a little guessing contest with prizes. Fifth-graders and above welcome.



Frank Morgan is the Webster Atwell 21 Professor of Mathematics at Williams College. He is a geometer working in minimal surfaces and studies the behavior and structure of minimizers in various settings. He  has over 150 publications and six books, including  Geometric Measure Theory: a Beginners Guide (4th ed. 2009)  and the popular Math Chat Book, based on his live, call-in Math Chat TV show and Math Chat column.  He is most famous for his proof, with students and colleagues of  the Double Bubble conjecture, that the minimum-surface-area enclosure of two given volumes is formed by three spherical patches meeting at 120-degree angles at a common circle.

Professor Morgan received his Ph.D. from Princeton in 1977 and  spent ten years on the faculty of MIT, serving part of this time as undergraduate mathematics chair. He then moved to Williams College where he also served as chair of the mathematics department. He was the founding director of the &quot;SMALL&quot; NSF undergraduate research project, vice-president of the Mathematical Association of America, vice-president of the American Mathematical Society.   Professor Morgan has received numerous awards including the MIT Everett Moore Baker Award for excellence in undergraduate teaching, 1982, the First National MAA Haimo Distinguished Teaching Award, 1992 and is a Fellow of the American Mathematical Society.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/abhl19oi8ani3gteivci3o2o44","2014-10-30 11:21:08","2015-02-11 12:05:03"
"2752","19",,"2014-11-05 15:00:00","2014-11-05 16:00:00","SAS 3282","Colby Long",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3n391nc4q72di55j9luopni2o8","2014-11-03 09:53:03",NULL
"2754","9","Multiscale Modelling in Physiology: Lungs and Saliva","2014-11-05 09:00:00","2014-11-05 10:00:00","SAS 4134","James Sneyd","https://www.math.auckland.ac.nz/people/jsne010","University of Auckland",,,"The modelling of physiological systems presents particular challenges. Events at the level of individual channels and receptors can affect the behaviour of an entire organ, via their control of cellular behaviour, and thus models need to span a wide range of spatial and temporal scales. However, despite their similarities, multiscale models also show great diversity, which requires a similar diversity of approach for their solution.
I shall consider two multiscale models in particular, one of the lung, one of the parotid salivary gland. Although both are multiscale, they are quite different in their essential natures. Our model of the lung relates the intracellular dynamics of calcium in airway smooth muscle cells to function at the level of the entire lung, taking into account along the way such matters as fluidisation of lung tissue and the development of heterogeneity in the lung.
Our multiscale model of the parotid salivary gland is, on the other hand, quite a different beast. Although calcium oscillations again are the major determinant of behaviour, in this case the structure of the gland and the properties of fluid transport suggest that the behaviour of the entire gland can be simply reduced to the behaviour of single cells, in which case our multiscale model is perhaps not so very multiscale after all.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/qh95h7hfjceb4t1ijfao2e1qng","2014-11-03 10:37:08",NULL
"2758","40","Careers in Mathematics","2014-11-05 18:00:00","2014-11-05 19:30:00","SAS 2229","CDC",,,,,"This year, weve teamed up with the CDC again, this time focusing on having a wide variety of panelists with mathematical backgrounds to talk to you about possible career options. On Wednesday, November 5th at 6-7:30pm in SAS 2229, we will be hosting a panel discussion followed by Q&amp;A for the entire panel with some refreshments. From freshmen to seniors, this is information you dont want to miss!

Stay tuned for updates about which companies will be represented and mark your calendars for this awesome opportunity to hear about your math career possibilities straight from the people doing it!","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/gq01pfkb07cb78681qbjgubdu0","2014-11-05 12:17:44",NULL
"2762","46","Algebraic and differential elimination in fundamental equations of quantum theory","2014-11-13 15:00:00","2014-11-13 16:00:00","SAS 4201","Andrey Akhmeteli",,"LTASolid Inc, Houston, TX","Irina Kogan",,"The charged scalar field can be algebraically eliminated from scalar electrodynamics (the Klein-Gordon-Maxwell electrodynamics). A similar result can be derived for a more realistic theory - spinor electrodynamics (the Dirac-Maxwell electrodynamics). The resulting theories describe independent evolution of electromagnetic field and can be embedded into quantum field theories using the generalized Carleman linearization. Another fundamental result: in a general case, the Dirac equation is equivalent to a 4th order partial differential equation for just one component, which can be made real by a gauge transform.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/acqr9736pgktlj19192ad7r1ds","2014-11-05 21:46:23",NULL
"2764","28","So you think you want to go to math grad school?","2014-11-19 15:00:00","2014-11-19 16:00:00","Poe 214",,,,,,"Ever wonder... how to choose the right grad school?  ...how long will grad school take? ...how much does it cost?  Come join us for our grad school panel with representatives from NCSU, UNC, &amp; Duke!  Snacks will be provided.","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/b16bk06lok0kuo2rvpk79glblk","2014-11-09 08:28:45",NULL
"2766","3","Biclosed sets in real hyperplane arrangements","2014-11-17 14:30:00","2014-11-17 15:30:00","SAS 4201","Thomas McConville","http://www.math.umn.edu/~mcco0489/","University of Minnesota",,,"The set of chambers of a real hyperplane arrangement may be
ordered by separation from some fixed chamber.  When this poset is a
lattice, Bjorner, Edelman, and Ziegler proved that the chambers are in
natural bijection with the biconvex sets of the arrangement.  For
finite reflection arrangements, this result may be strengthened to a
bijection between chambers and biclosed sets.  In this talk, we extend
this characterization of chambers to a wider class of arrangements, and
we apply this result to study graphs of reduced galleries.","sstella","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/gq73ai4v754p0c06aejimdjpp4","2014-11-10 11:34:46","2014-11-10 11:36:08"
"2770","19",,"2014-11-12 15:00:00","2014-11-12 16:00:00","SAS 3282","Dan Scofield",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/3m33sj58k222t49js6d377doi4","2014-11-10 21:15:50","2014-11-11 10:11:12"
"2772","46","Finite multiplicity theorem for spherical pairs","2014-11-20 15:00:00","2014-11-20 16:00:00","SAS 4201","Andrey Minchenko","http://www.wisdom.weizmann.ac.il/~/andreym/","The Weizmann Institute of Science",,,"Let X be a spherical space for a real reductive group G.
Recently, Kobayashi and Oshima, and independently Kroetz and Schlichtkrull have obtained results on boundedness of multiplicities of irreducible representations in the space of functions on X. We will consider another proof of these results, which seems to be shorter. One of the main steps is
to show that the singular support of a certain distribution on G (spherical character) is a Lagrangian in the cotangent bundle of G. We will also use some non-trivial facts about D-modules and Springer resolution. Another advantage of this approach is the possibility for generalization to the
p-adic case. The talk is based on a joint work of the speaker with A. Aizenbud and D. Gourevitch.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/mt29umqq4ia3f64eh7ebhad54k","2014-11-11 11:15:19",NULL
"2774","15","SIAM Meeting and Pizza","2014-11-17 12:25:00","2014-11-17 13:15:00","POE 214","Benjamin Seibold","https://www.math.temple.edu/~seibold/","Temple University",,,"Dr. Seibold will be the guest for the SIAM student chapter meeting. He will talk to students about careers, his research, and anything else students would like!

Everyone is welcome to attend. Pizza will be provided.","mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748%40group.calendar.google.com/private/full/3ounj0b5eeupq22rgfgl5dkck8","2014-11-12 16:16:52","2014-11-12 16:17:59"
"2776","23","Preparing for Interviews at the JMM","2014-11-21 15:00:00","2014-11-21 16:00:00","SAS 4201","Faculty and Postdoc Panel",,"NC State","Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/h1ohcoicgsdomnt26e7cf4vc74","2014-11-14 10:25:06","2014-11-14 10:27:47"
"2777","2","Scientific computing opportunities at Sandia National Laboratories","2014-11-19 17:00:00","2014-11-19 18:00:00","SAS 2225","Dr. Brian Adams",,"Sandia National Labs","Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/t4j0k7rn5f8ahpoh57136hcgn0","2014-11-14 18:31:47",NULL
"2779","11","Bloomberg Master Class","2014-11-21 13:30:00","2014-11-21 15:00:00","SAS 2225","Jeffrey Rockwell High",,"Captrust","Jeff Scroggs",,,"scroggs","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4%40group.calendar.google.com/private/full/l69873j47ittgglju1q81idjm0","2014-11-17 10:11:34","2014-11-21 09:46:19"
"2784","38","Complemented Leibniz Algebras - advised by Dr. Ernie Stitzinger","2014-11-25 13:30:00","2014-11-25 15:00:00","SAS 3282","Chelsie Batten Ray",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/4lpg5ai10qndsj113c5mfr4jso","2014-11-21 08:54:08","2014-11-21 08:54:44"
"2785","14","Undergraduate Research Presentations","2014-12-01 16:00:00","2014-12-01 16:40:00","SAS 2102","Patrick Gallagher and Matthew Loeffler",,,,,"1.  Patrick Gallagher
 
Title  :  Algebraic Topology and the Nielsen-Schreier Theorem
Abstract :  The Nielsen-Schreier theorem states that any subgroup H of a free group G is itself free, a rather difficult result to prove algebraically. However, the field of algebraic topology provides a rather simple, elegant proof of this theorem. This presentation will introduce free groups, the fundamental group of a space, and the concept of covering spaces. Then, these topics will be related to concepts in graph theory to construct the topological proof for the aforementioned theorem. Finally, this topological proof will be compared to Jakob Nielsens original algebraic proof of his namesake theorem for finitely generated free groups.  (Faculty Mentor: Dr. Tom Lada)
 
 
2. Matthew Loeffler
 
Title :  Sobol Indicies for an SIR Model
Abstract  : Sobol indicies are used to find influential inputs within a given model, which can be fixed to reduce later computations.  I show how two different methods to compute Sobol indicies compare in accuracy and running time.  The first method comes from Weirs, et al and is found to be more computationally costly but more accurate in comparison with the method from Smiths text.  These conclusions can be considered when deciding which method should be employed for a given models parameters to reduce the total cost of computations. (Faculty Mentor: Dr. Ralph Smith)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/7jed0gsq57fh5oe03pa4ijmhsc","2014-11-24 13:53:03",NULL
"2786","14","Undergraduate Research Presentations","2014-12-02 16:00:00","2014-12-02 17:00:00","SAS 2102","Samuel Magura, Andrew Marquis, and Georgy Scholten",,,,,"1.  Samuel Magura
 
Title :  Numerical Solution of the Helmholtz Equation over Irregular Domains
Abstract : The Helmholtz equation is the PDE that governs the propagation of waves of a single frequency. It is often infeasible to solve the Helmholtz equation analytically, so we turn to numerical methods instead. In this presentation, we discuss numerical methods for solving the equation over increasingly &quot;difficult&quot; 2D domains. First, we solve on a square domain using finite differences. Then, we introduce the method of difference potentials and apply it to solving over a circular domain. Finally, we discuss the problem posed by singular solutions and present a modification to the difference potentials algorithm that correctly handles singularities at reentrant corners.  (Faculty Mentor: Dr. Semyon Tsynkov)
 
 
2.   Andrew Marquis
 
Title : Sensitivity Analysis of Cardiovascular Models
Abstract :  Inverse Problems are a large area of interest to many Applied Mathematicians because there are no generalized analytic or numerical approaches to solving them. In the context of this presentation, a solution to an inverse problem is when one calibrates a models parameters so that the model output reflects a given data set. To solve an inverse problem many people begin by using some form of sensitivity analysis in order to study how the uncertainty in the output of a mathematical model can be described by different sources of uncertainty of the models inputs.  Over the summer of 2014, Dr. Mette S. Olufsen challenged my research group to create a Local Sensitivity Analysis software toolbox. To test that our MATLAB codes worked, we used an ODE model developed by Dr. Olufsen and Nakeya D. Williams, which predicts pulsatile blood pressure in humans.  The software that will be described in this presentation is comprised of three derivative based approaches of local sensitivity analysis. In addition to the local sensitivity descriptions, I will also describe a necessary model reformulation.  (Faculty Mentor: Dr. Mette Olufsen)
 
 
3.  Georgy Scholten
 
Title : Determinant and Permanent of Sylvester Matrix
Abstract : Let f and g be polynomials with integer roots, M be the Sylvester matrix of f and g and t be a term over the roots of the two polynomials. The main focus of the research project is to prove that t appears in the determinant of M if and only if it appears in the permanent of M.  (Faculty Mentor: Dr. Hoon Hong)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/b9d6taj6dge2i2jcljpajjq9vg","2014-11-24 14:39:19",NULL
"2787","43","My Model Has Too Many Parameters!  Active Subspaces for Dimension Reduction","2014-12-08 16:00:00","2014-12-08 17:00:00","SAS 4201 ","Paul Constantine","http://inside.mines.edu/~pconstan/","Colorado School of Mines","Ralph Smith",,"The goal of uncertainty quantification (UQ) is to formulate confidence metrics for computer simulations comparable to those for experiments. In practice, computing these UQ metrics involves parameter studies---e.g., numerical integration, numerical optimization, calibration, or response surface construction. But performing these parameter studies becomes increasingly difficult as the number of input parameters increases, especially when the simulation is expensive. The benefits of dimension reduction cannot be overstated. If one is able to approximate a 10-parameter simulations prediction by a comparable interface with 2 parameters, then several otherwise intractable techniques become feasible.

I will discuss our research efforts and progress on active subspaces for dimension reduction. The idea is to discover and exploit important linear combinations of the input parameters to reduce the effort for thorough parameter studies in complex simulations.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/eoiln6jo9gnoosvku0688s94os","2014-12-03 11:00:19",NULL
"2789","46","The geometry of periodic equi-areal sequences","2015-01-29 15:00:00","2015-01-29 16:00:00","SAS 4201","Robert Bryant","http://fds.duke.edu/db/aas/math/faculty/bryant/","Duke","Andrew Cooper","http://www4.ncsu.edu/~aacoope2/bryantabstract.pdf","A sequence of functions f_i on a surface S is said to be &quot;equi-areal&quot;
if the pairs (f_1, f_2), (f_2, f_3), etc. all define (local) coordinate
systems that induce the same area form on the surface.

The equi-areal sequences that are n-periodic for low values of n
turn out to have close connections with interesting problems
in dynamical systems and in the theory of cluster algebras.

In this talk, I will explain what is known about the classification
(up to a natural notion of equivalence) of such sequences
and their surprising relationships with differential geometry,
cluster algebras, and the theory of overdetermined differential equations.
I wont assume that the audience knows much differential geometry,
just basic multi-variable calculus, and the emphasis will be on
describing the interesting results rather than on technical details.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dj99jjpjs8ofou8nijjl3kljks","2014-12-15 17:39:32","2015-01-14 19:07:42"
"2790","43","New Insights On Anomalous Localized Resonance Phenomena","2015-01-15 16:00:00","2015-01-15 17:00:00","SAS 4201","Daniel Onofrei","http://www.math.uh.edu/~onofrei/","U of Houston","Pierre Gremaud",,"Anomalous localized resonance phenomena is observed at the
interface between positive index and negative index materials. In this talk
we will mainly discuss about the anomalous localized resonance phenomena in
the quasistatic regime in the case when a general charge density
distribution is brought near a slab with its electrical permittivity having
negative real part. 

In the first part of the talk we will offer a brief review of the literature
and highlight the main results: first, if the charge density distribution is
within a critical distance of the slab,
then the power dissipation within the slab blows up as certain electrical
dissipation parameters go to zero inside the slab, and second, 
if the charge density distribution is further than this critical distance
from the slab, then the power dissipation within the slab remains bounded.
Then, in the remaining part of the presentation, we will present our recent
results regarding the sensitivity of the anomalous localized phenomena with
respect to small losses outside the slab. We will analytically show how the
critical distance depends on the rate at which the loss parameter outside
the slab goes to zero and discuss explicit blow up rates for the associated
dissipated power in the slab. Relevant examples and representative numerical
support will enhance our discussion. Finally, we will conclude the talk with
a discussion of open questions and physically relevant extensions of the
results.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/seogl72klvvc8147fd7bfeghcc","2014-12-16 12:26:40",NULL
"2791","43","Inversion, design of experiments, and optimal control in systems governed by PDEs with random parameter functions.","2015-01-22 16:00:00","2015-01-22 17:00:00","SAS 4201","Alen Alexandrian","http://users.ices.utexas.edu/~alen/","UT Austin","Pierre Gremaud",,"Mathematical models of physical phenomena often include parameters that are hard or impossible to measure directly or are subject to variability, and are thus considered uncertain. Different aspects of modeling under uncertainty include forward uncertainty propagation, statistical inversion of uncertain parameters, optimal design of experiments, and optimization under uncertainty. I will focus on recent advances in numerical methods for infinite-dimensional Bayesian inverse problems and optimal experimental design. I will also discuss the problem of risk-averse optimization under uncertainty with applications to
control of PDEs with uncertain parameters. The driving applications are systems governed by PDEs with uncertain parameter fields, such as flow in the subsurface with an uncertain permeability field, or the diffusive transport of a contaminant with an uncertain initial condition. Such problems are computationally challenging due to expensive forward solves and innite-dimensional
(high-dimensional when discretized) parameter spaces.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/sa4tmt2p08ou1onqm4btf38gu0","2014-12-16 12:33:25","2015-01-07 18:27:05"
"2792","43","Computationally Efficient Techniques for Large-Scale Inverse Problems","2015-01-23 16:00:00","2015-01-23 17:00:00","SAS 4201","Arvind Saibaba","http://www.eecs.tufts.edu/~arvindks/","Tufts","Pierre Gremaud",,"Inverse problems use physical measurements to infer system parameters; for example, Diffuse Optical Tomography reconstructs images of the body from measurements obtained using near infra-red light. Inverse problems for which the underlying physics can be mathematically modeled by partial differential equations are computationally challenging because they typically require repeated solutions of large-scale linear systems and an efficient representation of prior information of the parameters that we wish to estimate. I will describe various numerical schemes such as solvers, preconditioners and compression techniques designed  to reduce the computational cost involved with estimating the parameters of interest and quantifying the uncertainty in the resulting reconstructions. The resulting algorithms have significant computational gains and scale to large problem sizes. I will illustrate these methods through specific numerical examples from two different application areas - Diffuse Optical Tomography used for breast cancer detection, and Hydraulic Tomography used to estimate subsurface hydrological parameters in groundwater flow.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/p78ob5j0if4u8rbe3a3vokm4so","2014-12-16 13:35:38","2015-01-08 14:22:17"
"2793","43","Interface Motion, Jet Schemes, and Gradient-Augmented Level Set Methods","2015-01-27 16:00:00","2015-01-27 17:00:00","SAS 4201","Benjamin Seibold","https://math.temple.edu/~seibold/","Temple","Pierre Gremaud",,"The accurate and robust numerical evolution of interfaces is an
important challenge in many science and engineering problems,
including multi-phase fluid flow computations, phase transitions,
weather fronts, and shock tracking. The level set methodology does
yield robustness, in particular when the interface can undergo
topology changes. However, numerical methods traditionally used in
this context (e.g. WENO) incur a variety of drawbacks due to their
wide stencils.

Gradient-augmented level set methods (GALSM) can overcome many of
these drawbacks. These semi-Lagrangian approaches achieve high-order
accuracy in an optimally local fashion, by evolving derivative
information in addition to function values. GALSM possess sub-grid
resolution and yield accurate curvature approximations. We demonstrate
how the approaches sub-grid resolution can serve to benefit two-phase
fluid flow simulations, and how its optimal locality gives rise to a
straightforward combination with adaptive mesh refinement (AMR).

Interpreted in the context of more general advection equations, GALSM
generalize to jet schemes, which are high-order numerical methods than
can be derived from an evolve-and-project methodology in function
spaces. We outline some stability concepts for jet schemes, and
demonstrate their computational efficiency compared to WENO and
Discontinuous Galerkin schemes.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/k4toerv6h3hvhv7rvsd75cb5sg","2014-12-16 13:40:21","2015-01-15 10:43:58"
"2794","43","Controlling a Thermal Fluid: Theoretical and Computational Issues","2015-01-08 16:00:00","2015-01-08 17:00:00","SAS 4201","Weiwei Hu","http://dornsife.usc.edu/cf/faculty-and-staff/faculty.cfm?pid=1043407","U of Southern California","Pierre Gremaud",,"Design and control of thermal fluid systems is an area with a multitude of interesting and important problems in complex engineering systems. In this talk, we discuss feedback boundary  stabilization  and numerical simulation  of a thermal fluid described by the Boussinesq equations.  This problem is motivated by the design and operation of low energy consumption buildings.  We first show that it is possible to locally exponentially stabilize the nonlinear Boussinesq Equations by means of finite dimensional Neumann/Robin type boundary controls acting only on a portion of the boundary. The feedback controller is obtained by solving a Linear Quadratic Regulator problem for the linearized Boussinesq equations. A two dimensional problem is employed to illustrate the ideas based on Taylor-Hood finite elements and  to suggest areas for future research.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/6eig56j5qu103s6t10d3sjr2bc","2014-12-16 13:46:56","2014-12-18 13:28:51"
"2795","43","Parallel and distributed optimization","2015-01-14 16:00:00","2015-01-14 17:00:00","SAS 4201","Ming Yan","http://www.math.ucla.edu/~yanm/","UCLA","Pierre Gremaud",,"Due to the explosion in size and complexity of modern datasets, both the decentralized collection or storage of these datasets as well as accompanying parallel and distributed solution methods are either necessary or at least highly desirable. In this talk, I will introduce several ways to move from single threaded optimization algorithms to parallel and distributed approaches with examples: direct parallel and distributed implementation, modification of current algorithms and implementation in the parallel and distributed manner, and new algorithms suitable for parallel and distributed platforms. However, there are some new issues in parallel and distributed computing, and I will talk about asynchronous optimization algorithms, which provide ways to deal with the issue of synchronization.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/h1ss5ijoh4eh43bb80o2jhpp8o","2014-12-16 13:52:32","2014-12-23 09:47:17"
"2796","4","Controling stable and unstable manifolds in nonautonomous flows","2015-01-23 15:00:00","2015-01-23 16:00:00","SAS 2102","Sanjeeva Balasuriya","http://www.maths.adelaide.edu.au/sanjeeva.balasuriya/","University of Adelaide","Steve Schecter",,"Stable and unstable manifolds form important flow separators in autonomous (steady) flows.  They continue to play this role in nonautonomous (unsteady) flows, but the fact that they are moving in time has implications for transport.  For example, their known role in improving mixing rates in micro- and nano-fluidic devices has led to an interest in harnessing this motion efficiently.  This talk addresses how to control their movement in a user-defined fashion via an imposed velocity, in three different senses.  First, a method for controling hyperbolic trajectories (the trajectories to which trajectories lying on the manifolds decay in forwards and backwards time) in any dimension is presented.  Second, the direction of emanation of the manifolds from the hyperbolic trajectories is addressed.  Third and finally, segments of stable and unstable manifolds are controled in two dimensions under certain restrictions.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/egtm3ktip9ep2vpok62qevik7k","2014-12-18 14:18:48","2015-01-05 11:08:14"
"2797","43","Fast direct methods for structured matrices","2015-01-20 16:00:00","2015-01-20 17:00:00","SAS 4201","Kenneth Ho","http://web.stanford.edu/~klho/","Stanford","Pierre Gremaud",,"Many linear systems arising in practice are governed by rank-structured matrices. Examples include PDEs, integral equations, Gaussian process regression, etc. In this talk, we describe our recent work on fast direct algorithms that exploit such structure. These methods are of particular interest due to their exceptional robustness and high capacity for information reuse. Our main technical achievement is a linear-complexity matrix factorization as a generalized LU decomposition. This factorization permits fast multiplication/inversion and furthermore supports rapid updating. We anticipate that such techniques will be game-changing in environments requiring the analysis of many right-hand sides or the solution of many closely related systems, such as in protein design or other inverse problems. Similar applications abound in computational statistics and data analysis.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/2dns8ge6koo1ovsocqfspjqsoc","2014-12-22 13:07:17","2015-01-13 12:27:20"
"2798","14","Spring Mathematics Departmental Meeting","2015-01-07 16:00:00","2015-01-07 17:00:00","SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/l637k7gkrie2i59bmirr7la8eg","2015-01-05 10:41:42",NULL
"2799","14","Spring Math Departmental Meeting Reception","2015-01-07 15:30:00","2015-01-07 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/v43gb3re70sq1ts8io5rnmm1a8","2015-01-05 10:46:26",NULL
"2800","46","A biclsutering framework for consensus problems","2015-01-12 16:00:00","2015-01-12 17:00:00","SAS 2106","Mariano Tepper","http://duke.academia.edu/MarianoTepper","Duke","Irina Kogan",,"We consider grouping as a general characterization for problems such as clustering, community detection in networks, and multiple parametric model estimation. We are interested in merging solutions from different grouping algorithms, distilling all their good qualities into a consensus solution. In this talk, I present a biclustering framework for reaching consensus in such grouping problems. In particular, this is the first time that the task of finding/fitting multiple parametric models to a dataset is formally posed as a consensus problem. I highlight the equivalence of these tasks and establish the connection with the computational Gestalt program, that seeks to provide a psychologically-inspired detection theory for visual events. I also present a simple but powerful bi-clustering algorithm, specially tuned to the nature of the problem we address, though general enough to handle many different instances inscribed within our characterization. The presentation is accompanied with diverse and extensive experimental results in clustering, community detection, and multiple parametric model estimation in image processing applications.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/402apu01n063v3l3o0l1u6r62c","2015-01-05 20:15:29","2015-01-06 10:55:10"
"2801","46","Surface bendings via Darboux integrability and holomorphic maps","2015-02-09 16:00:00","2015-02-09 17:00:00","SAS 2106","Thomas Ivey","http://iveyt.people.cofc.edu/","College of Charleston","Irina Kogan",,"We set up the problem of isometrically immersing a given Riemannian surface into Euclidean space using an exterior differential system, and find that there are four distinct metrics (up to scale) for which the system is Darboux integrable. Thus, for these metrics the immersion can be explicitly determined by a choice of two arbitrary functions of a real variable (in the hyperbolic case) or one holomorphic function (in the elliptic case). We give geometric interpretations for this data, derive a Weierstrass-type integral formula for the immersion (which in turn implies that these surfaces are affine-minimal), and discuss how initial value problems might be solved using the action of the Vessiot group.
This is joint work with Jeanne Clelland, Ben McKay and Peter Vassiliou.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/kgeukloasohihdjkl1voj3vu5k","2015-01-05 20:16:35","2015-01-25 15:46:51"
"2802","46","A multiscale version of the Mapper algorithm","2015-04-09 15:00:00","2015-04-09 16:00:00","SAS 4201","Facundo Memoli","https://people.math.osu.edu/memoli.2/","Ohio State","Irina Kogan",,"Summarizing information from datasets is a central theme in topological data analysis. Mapper, a tool for such summarization, takes as input a dataset, a function defined on it, and a covering of the codomain of the function, and with this information produces a reduced view of the data in the form of simplicial complex. Different choices of the function emphasize different properties of the data. Mapper has been successfully employed in a variety of scientific applications. We wanted to study in which sense Mapper might be stable under perturbations of its inputs. For this, we study a multiscale version of the Mapper construction in which, instead of a simple cover of the codomain, we take into account a whole hierarchical family of covers. Thus, instead of a single simplicial complex, we now give rise to a directed family of simplicial complexes connected by simplicial maps. I will describe this multiscale construction and our current understanding of its  stability properties.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mbcpb36euvgeb2gufj8ft9c46c","2015-01-05 20:18:27","2015-03-28 21:29:41"
"2803","36",,"2015-01-23 15:00:00","2015-01-23 16:00:00","SAS 4201","Zhilin Li and Mette Olufsen",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5o4rghdr94buthe10vrkoo4tak","2015-01-06 10:03:15","2015-01-07 08:51:39"
"2804","36",,"2015-01-30 15:00:00","2015-01-30 16:00:00","SAS 4201","Min Kang and Seth Sullivant",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3j664ublcdb8vrk1oe1strnj70","2015-01-06 10:09:03","2015-01-07 08:52:07"
"2805","36",,"2015-02-13 15:00:00","2015-02-13 16:00:00","SAS 4201","Radmila Sazdanovic and Cynthia Vinzant",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9b3631p6jpmcahcn0stib8go2o","2015-01-06 10:09:58","2015-01-07 08:52:48"
"2806","36",,"2015-02-20 15:00:00","2015-02-20 16:00:00","SAS 4201","Pierre Gremaud and Kazufumi Ito",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9mk4117674jng4brrk3jk7kkb0","2015-01-06 10:10:34","2015-01-14 09:27:29"
"2807","36",,"2015-03-20 15:00:00","2015-03-20 16:00:00","SAS 4201","Mansoor Haider and Negash Medhin",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2knepto7d05pa3tbga6ghea7mo","2015-01-06 10:11:35","2015-01-07 08:53:48"
"2808","36",,"2015-04-10 15:00:00","2015-04-10 16:00:00","SAS 4201","Stephen Schecter and Dmitry Zenkov",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/10munhojtj5fi61gcu22g4fhag","2015-01-06 10:12:28","2015-02-04 12:04:00"
"2809","23","GIST event: Panel on Alternative Classroom Techniques","2015-02-06 15:00:00","2015-02-06 16:00:00","SAS 4201","Faculty Panel",,"NC State","GIST",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/lk6058pk4irbhu00oo8l3nfdpk","2015-01-06 16:09:13","2015-01-06 16:20:00"
"2810","23","Experiences from the Joint Math Meetings","2015-01-16 15:00:00","2015-01-16 16:00:00","SAS 4201","Graduate Student Panel",,"NC State","Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sp4t9luch49ul8162npphgmtmo","2015-01-06 16:11:42",NULL
"2811","24","Welcome Back Pizza Social","2015-01-14 17:15:00","2015-01-14 19:00:00","SAS 4104",,,,,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ieaagqfnnir1c09a2vseks5hhk","2015-01-06 19:05:09",NULL
"2812","14","Tea for Applied Math Colloquium","2015-01-08 15:30:00","2015-01-08 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/v9q0me09016deb5o3d1cmjrqgc","2015-01-08 10:20:37",NULL
"2813","4","Long-term Analysis of p-Laplacian Evolution Equations","2015-02-11 15:00:00","2015-02-11 16:00:00","SAS 4201","Pelin Guven Geredeli",,"Hacettepe University, Turkey","Lorena Bociu and Justin Webster",,"In this work, we consider the nonlinear evolution equation of parabolic type
$u_t - div(|\grad u|^(p-2)|\grad u|)+f(u) = g$. We analyze the long time dynamics (in the sense of global attractors) under very general conditions on the nonlinearity f. Since we do not assume any polynomial growth condition on it, the main difficulty arises at first in the proof of wellposedness. Here, the critical issue is to deal with the limiting procedure on f which is overcome utilizing the weak convergence techniques in Orlicz spaces. Then, proving the existence of the global attractors in $L^2 (\Omega)$ and in more regular space $W^(1,p)_0 (\Omega)$, we show that they coincide. In addition, if f is monotone and g = 0, we give an explicit estimate of the decay rate to zero of the solution.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/k5e7n8lk9cqmcckbrmjrneagq4","2015-01-09 11:12:06","2015-01-27 13:20:16"
"2814","1","Variational formulations of coupled systems of mechanics and diffusion","2015-04-21 16:00:00","2015-04-21 17:00:00","SAS 1102","Ralph Showalter","http://math.oregonstate.edu/people/view/show","Oregon State University","Lorena Bociu",,"We review some basic results on the solvability of equations in function spaces and describe some applications to various initial-boundary-value problems for coupled systems of fluid flow and deformable media.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/e2phht0hae9brt0uhsfcl731q8","2015-01-09 11:27:01","2015-01-20 10:43:15"
"2815","2","Hepatitis C virus dynamics: models, analysis, and implications","2015-01-16 09:00:00","2015-01-16 10:00:00","SAS 4201","Libin Rong","https://files.oakland.edu/users/rong2/web/","Oakland University","Tom Banks",,"Chronic hepatitis C virus (HCV) infection remains a public health problem worldwide. Traditional interferon-based therapy leads to viral eradication in less than 50% of treated patients. New treatment using direct-acting antiviral drugs has significantly increased the cure rate. These new drugs directly interfere with different steps of the HCV replication cycle. Thus, existing models that do not consider within-cell processes may not be optimal in analyzing data from patients treated with new drugs. In this talk, I will review mathematical models used to study HCV dynamics under traditional therapy, and discuss recent advances in the development of multiscale models for new drugs. I will address model analysis, approximation, comparison with patient data, and the implications for developing new treatment strategies for hepatitis C.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/7n9mlqrc0jaq3lfio2a2ri96jg","2015-01-09 18:11:48","2015-01-09 18:17:59"
"2816","2","Mathematical modeling of clinical and cellular data with applications to personalized medicine","2015-01-15 09:00:00","2015-01-15 10:00:00","SAS 4201","Kevin Flores","http://www4.ncsu.edu/~kbflores/","NC State","Tom Banks",,"I will show how dynamic mathematical models can be used to interpret longitudinal data in both clinical and in vitro biomedical research, focusing on within-host disease dynamics of Chronic Myelogenous Leukemia (CML) and HIV infection, and cellular dynamics in synthetic gene networks. 

CML is a hematological malignancy caused by expression of the mutant BCR-ABL gene. Although molecular inhibition of the BCR-ABL protein has become the therapeutic standard for CML patients, resulting in the rapid decline of CML cells, approximately one-third of patients fail to respond to therapy or develop therapy resistance after an initial response. I will present a model of CML that was developed to aid in the patient-specific prediction of resistance to BCR-ABL inhibition therapy. Similarly, anti-retroviral therapy (ART) can reduce the viral load to undetectable levels in HIV patients, but ART-resistant latently infected cells (reservoir cells) may reseed infection after ART cessation. I will present a model of HIV infection and reservoir cells that was developed to predict patient-specific outcomes and help propose novel treatment strategies.

Synthetically engineered yeast cells are a eukaryotic system used to investigate genetic networks that drive human diseases. Recent findings suggest that several developmental and disease processes may rely on the capacity of isogenic cell populations to generate gene expression variability, leading to phenotypic heterogeneity despite genetic and environmental uniformity. I will present a structured population modeling framework, which couples intracellular dynamics with cell proliferation, that can be used to quantify and predict gene expression noise in data generated from synthetic cell experiments. I will also exemplify how optimal design theory can be used to predict dynamic perturbations to cellular experiments that can increase the information content of the resulting longitudinal data sets.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/s3pf04n14psockosiapm4sdvls","2015-01-09 18:13:15","2015-01-09 18:17:03"
"2817","19",,"2015-01-14 15:00:00","2015-01-14 16:00:00","SAS 2012","Dan Scofield",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1sar02600ius3ml231uff5mgq0","2015-01-12 13:21:50",NULL
"2818","19","introduction to Matroids","2015-01-21 15:00:00","2015-01-21 16:00:00","SAS 2102","Dan Bernstein",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/e9kovbffcli338tdfpdr4tvcco","2015-01-12 13:22:44","2015-01-20 11:19:41"
"2819","8","Identifiability of Linear Compartment Models","2015-01-27 16:30:00","2015-01-27 17:30:00","SAS 2102","Nikki Meshkat","http://www4.ncsu.edu/~ncmeshka/","NC State",,,"Identifiability concerns finding which unknown parameters of a model can be determined from given input-output data. Many linear ODE models, used primarily in Systems Biology, are unidentifiable, which means that parameters can take on an infinite number of values and yet yield the same input-output data. We study a particular class of unidentifiable models and find conditions to obtain identifiable reparametrizations of these models. In particular, we use a graph-theoretic approach to analyze the models and show that graphs with certain properties allow a monomial scaling reparametrization over identifiable functions of the parameters.  We also examine conditions to obtain identifiability for this class of models, and in particular, show how identifiability can be determined by simply looking at the graphical structure of these linear compartment models.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/vqlu788v18htqil8r8bec9pt0c","2015-01-13 09:32:16","2015-01-20 23:14:15"
"2820","8","Computing the parameterized differential Galois group of a second-order linear differential equation with parameters","2015-02-03 16:30:00","2015-02-03 17:30:00","SAS 4201","Carlos Arreche","http://www4.ncsu.edu/~cearrech/","NC State",,,"Consider a second-order linear differential equation with respect to d/dx, whose coefficients are rational functions with respect to x and the parameters t_1,...,t_m. The parameterized Picard-Vessiot theory associates a differential Galois group G to such an equation. In analogy with the classical Picard-Vessiot theory of Kolchin, G measures the differential-algebraic relations amongst the solutions to the equation, with respect to d/dx as well as the parametric derivations d/dt_1,...,d/dt_m. After giving a basic introduction to the parameterized Picard-Vessiot theory, I will describe algorithms to compute G, and how these algorithms may be used to decide the differential transcendence of the solutions.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/oebvu9pq6r5odcicopc9b38id8","2015-01-13 09:34:26","2015-01-21 11:37:48"
"2821","8","Bounds for Generalized Hamming Weights of Algebraic Geometry Codes","2015-02-10 16:30:00","2015-02-10 17:30:00","SAS 4201","Kwankyu Lee",,"Chosun University",,,"Goppas codes on algebraic curves defined over finite fields, called AG codes, are usually regarded as the most successful class of error correcting codes in theory as well as in practice. 

We present a good bound for the generalized Hamming weights of multi-point evaluation and differential AG codes. It is a natural generalization of the order bound for the dual of one-point evaluation AG codes. As an example, we determine the third generalized Hamming weight of a two-point evaluation Hermitian code. 

Then we extend the bound for the relative generalized Hamming weights, which are essential measures of the performance of secret sharing schemes based on linear codes. The access structure of a secret sharing scheme based on the two-point Hermitian code and its subcode is analyzed using the new bound.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/utboodqbjjri81b6g5r9phcv1k","2015-01-13 09:58:06",NULL
"2822","11","The Optimal Execution Strategy of Employee Stock Option","2015-01-21 16:00:00","2015-01-21 17:00:00","SAS 4201","Dr. Yi Fu",,"School of Finance and Business, Shanghai Normal University",,,"In this paper, we develop an optimal execution strategy for employee stock options by means of the fluid model, in which a voluntary turnover
is considered. We show that the value function is the viscosity solution of
the Hamilton-Jacobi-Bellman variational inequality equation and prove the
uniqueness of the viscosity solution. Finally, we present numerical illustrative
examples and numerical solutions of optimal strategies computed by the finite
difference method.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/596c25midmd3ner9r8qj2voa98","2015-01-14 12:24:59",NULL
"2823","7","The Optimal Execution Strategy of Employee Stock Option","2015-01-21 16:00:00","2015-01-21 17:00:00","SAS 4201","Dr. Yi Fu",,"School of Finance and Business, Shanghai Normal University",,,"In this paper, we develop an optimal execution strategy for employee stock options by means of the fluid model, in which a voluntary turnover
is considered. We show that the value function is the viscosity solution of
the Hamilton-Jacobi-Bellman variational inequality equation and prove the
uniqueness of the viscosity solution. Finally, we present numerical illustrative
examples and numerical solutions of optimal strategies computed by the finite
difference method.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/vgqq6kup0hn4fnr04c7i5nss4s","2015-01-14 17:41:03",NULL
"2825","28","AWM Brown Bag Lunch","2015-01-22 12:15:00","2015-01-22 13:15:00","3rd floor grad student lounge",,,,,,"Please join us for our first weekly lunch of the semester.  If you cant make it this Thursday, we hope to see you next week!","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/0mf6t69kg08q0ngbosm66d0g3k","2015-01-15 14:48:42","2015-01-16 11:03:14"
"2827","28","AWM Brown Bag Lunch","2015-01-29 12:15:00","2015-01-29 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/n5ggojhrevqdcv0agesdbee7s8","2015-01-15 14:49:15","2015-01-16 11:03:30"
"2829","2","Mathematical modeling of multi-scale dynamics and treatments of infectious disease","2015-01-21 09:00:00","2015-01-21 10:00:00","SAS 4201","Ruian Ke",,"Los Alamos National Laboratory","Tom Banks",,"It is widely acknowledged that infectious disease remains one of the major challenges facing human society in the 21st century. The infection, transmission and evolution of infectious diseases span several scales of biological organization, i.e., intracellular, cellular and population scales. Solutions to problems at a larger scale, such as disease pandemics and epidemics, often require interventions at lower scales, such as vaccines, drug treatments and gene therapies. In this talk, I will give an overview of my research into unraveling the mechanisms of how drug treatments and pathogen genetic mutations would impact disease progression and transmission using mathematical techniques, such as dynamical systems, stochastic processes, information theory, statistics, population genetics and phylogenetics. I will primarily focus on three topics: 1) transmission of defective dengue viruses, 2) individualized treatment strategies for hepatitis C virus infection to avoid drug resistance, and 3) parameter estimation from clinical trials of HIV latency reversing agents.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/l0qt55e9vruhkn2i2a2t18t1d0","2015-01-15 15:16:32",NULL
"2831","2","The Dynamics of Drug Resistance: A Mathematical Perspective","2015-01-20 09:00:00","2015-01-20 10:00:00","SAS 4201","Orit Lavi",,"National Institutes for Health","Tom Banks",,"Resistance to chemotherapy is a key impediment to successful cancer treatment that has been intensively studied for the last three decades. Several central mechanisms have been identified as contributing to the resistance. Mathematical models of drug resistance have dealt with many of the known aspects of this field. We will discuss new quantitative approaches of mathematical analysis that can be used in combination with other experimental and clinical tools. Mainly, we will explore several important issues about mechanisms of redundancy, heterogeneity, biological importance and drug resistance, discuss methodological challenges and describe our approaches. The new insight provided by our models could help to dramatically change the ability of clinical oncologists to design new treatment protocols and analyze the response of patients to therapy.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3f17ki68t7l73mb4nivqreii0s","2015-01-15 15:17:50",NULL
"2833","21","Triangle Lectures in Combinatorics","2015-02-21 09:00:00","2015-02-21 17:00:00","SAS 1102",,,,,"https://www.math.ncsu.edu/courses/TLC/",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/apjunlrj721a0fjv9ufqfgkbic","2015-01-15 16:46:11","2015-02-12 11:42:49"
"2834","14","Departmental Tea","2015-01-20 15:30:00","2015-01-20 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/7heu650do7695odkatrsoa1teo","2015-01-16 17:08:46",NULL
"2835","14","Departmental Tea","2015-01-21 15:30:00","2015-01-21 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ffdi15vtv6g8ojov1fmg5el4v4","2015-01-16 17:10:06",NULL
"2836","14","Departmental Tea","2015-01-22 15:30:00","2015-01-22 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2vtisftq6bgmi7e1pc60evisqo","2015-01-16 17:10:49",NULL
"2837","14","Departmental Tea","2015-01-23 15:30:00","2015-01-23 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ot9ljcrc6tv2touludhaaga3e8","2015-01-16 17:11:25",NULL
"2839","19",,"2015-01-28 15:00:00","2015-01-28 16:00:00","SAS 2102","Shira Polster",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/i0qmcghpio8m1o33ldoen1iok8","2015-01-19 16:17:00","2015-01-20 11:20:01"
"2840","19",,"2015-02-04 15:00:00","2015-02-04 16:00:00","SAS 2102","Levi Biock",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fv9oq158d6rg75sdft1psphml8","2015-01-19 16:18:25","2015-01-20 11:20:09"
"2841","19",,"2015-02-11 15:00:00","2015-02-11 16:00:00","SAS 2102","Emily Barnard",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mnj5hr6iit5rk7fcj9d0c4bopg","2015-01-19 16:19:09","2015-01-20 11:20:17"
"2842","3","Toda systems, cluster characters, and spectral networks","2015-02-20 14:30:00","2015-02-20 15:30:00","SAS 2102","Harold Williams",,"UT Austin","Salvatore Stella",,"The past decade has revealed a deep but hidden interplay between the geometry of character varieties of surfaces and the representation theory of quivers.  One rough way of stating this is that the coordinate ring of a (possibly wild) character variety can be viewed as a kind of Hall algebra for a quiver with potential.  More precisely, the geometric and representation-theoretic points of view on this algebra come with a priori distinct prescriptions for &quot;canonical&quot; elements, which coincide despite their definitions being fundamentally different in nature.  We will discuss recent progress developing this circle of ideas, in particular for higher-rank gauge groups.  A key organizing principle is the notion of cluster algebras and their canonical bases, whose origins go back to the work of Lusztig and Kashiwara in Lie theory.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2lqh2p03qsvhtufisgo99dsga8","2015-01-25 23:05:21","2015-02-16 15:22:53"
"2843","14","Departmental Tea and Cookies","2015-01-27 15:30:00","2015-01-27 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nu4vrmqtt8v340bt0kk9m950p8","2015-01-26 10:10:09",NULL
"2844","46","Object-image correspondence for algebraic curves under projections","2015-02-02 16:00:00","2015-02-02 17:00:00","SAS 2106","Irina Kogan","http://www4.ncsu.edu/~iakogan/","NC State","Irina Kogan",,"I will present a novel algorithm for deciding whether a given planar curve is an image of a given spatial curve, obtained by a central or a parallel projection with unknown parameters. The motivation comes from the problem of establishing a correspondence between an object and an image, taken by a camera with unknown position and parameters. Our algorithm is based on projection criteria that reduce the projection problem to a certain modification of the equivalence problem of planar curves under affine and projective transformations. To solve the latter problem we make an algebraic adaptation of signature construction that has been used to solve the equivalence problems for smooth curves.  Our algorithm, in comparison to the straightforward approach, allows a significant reduction of a number of real parameters that need to be eliminated. 
This is a joint work with Joseph Burdis and Hoon Hong.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mgfkear1uuj0k1imdtb8his12c","2015-01-27 00:13:22","2015-01-30 18:34:19"
"2846","46","Circle-Valued Temperatures","2015-02-23 16:00:00","2015-02-23 17:00:00","SAS 2106","Andrew Cooper","http://www4.ncsu.edu/~aacoope2/","NC State","Andrew Cooper",,"Temperature is usually measured as a real number, say as the level of mercury in a glass tube or the number on a digital display. But some thermometers give their reading by position along a circular dial; such readings should really be thought of as an angle, not a number. If we overload the thermometer so that the needle spins around several times, we dont know what the real temperature is. 

In this talk, Ill show that with a little bit of algebraic topology, we can deduce that the qualitative behavior of circle-valued temperature functions is largely the same as that of their real-valued cousins.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jbo47nvjttdd6s4jgpe6l8q5as","2015-01-27 00:16:49","2015-02-05 20:58:31"
"2847","4","Shock curves and rarefaction curves","2015-03-25 15:00:00","2015-03-25 16:00:00","SAS 4201","Mike Benfield",,"NC State",,,"Shock and rarefaction curves feature prominently in the theory of hyperbolic conservation laws. Here we present several results related to their geometry, in particular when they coincide. This is part of a longer term plan to construct examples exploring the limits of the general theory of well-posedness in hyperbolic conservation laws.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5gh6vi5abj2unpjelsuuldlduo","2015-01-27 13:21:29","2015-03-22 11:55:20"
"2848","3","Quantum Pfaffians and generalizations","2015-03-02 14:30:00","2015-03-02 15:30:00","SAS 4201","Naihuan Jing","http://www4.ncsu.edu/~jing/","NC State",,,"The first 10 minutes will cover the most important materials in linear algebra
but in an extremely easy way. Then we use quantum exterior algebras to give a new and elementary formulation of quantum Pfaffians and generalized quantum Pfaffians based on quantum Pluecker relations. In this approach, the quantum Pfaffians are for any square matrix satisfying a simple quadratic relation. In particular, we prove the fundamental identity expressing any quantum determinant as a quantum Pfaffian. This is joint work with Jian Zhang.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3nfstqi0dlhqf2crhm4auvfntk","2015-01-28 14:51:11",NULL
"2849","46","A Khovanov stable homotopy type","2015-03-19 15:00:00","2015-03-19 16:00:00","SAS 4201","Robert Lipshitz","http://www.math.columbia.edu/~lipshitz/","Columbia University","Radmila Sazdanovic",,"We will start by recalling the (original) definition of the Khovanov homology of a knot, and some of its key properties.  We will then introduce a stable homotopy refinement of Khovanov homology, and mention some modest applications of it.  The new content is joint with Tyler Lawson and Sucharit Sarkar; there is related work by Hu-Kriz-Kriz.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qohak1m1rq7pb7snced5lc7ngk","2015-01-28 15:53:38","2015-02-09 22:41:16"
"2850","8","Elementary certificates in semidefinite programming","2015-03-24 16:30:00","2015-03-24 17:30:00","SAS 4201","Gabor Pataki","http://www.unc.edu/~pataki/","UNC Chapel Hill",,,"Semidefinite Programming (SDP) is the problem of optimizing a linear objective function of a symmetric positive semidefinite matrix variable. SDP is much more general than linear programming, with applications from engineering to combinatorial optimization. 

In SDP, unlike in linear programming, Farkas lemma may fail to prove infeasibility. Here we obtain an exact, short certificate of infeasibility in SDP by an elementary approach: we reformulate semidefinite systems using only elementary row operations, and rotations. When a system is infeasible, the reformulated system is trivially infeasibile.  

As a corollary, we obtain algorithms to generate the data of all infeasible SDPs; and the data of all feasible SDPs whose maximum rank feasible solution has a prescribed rank.

In somewhat different language, our reformulations provide a standard form of spectrahedra, to easily verify either their emptiness, or a tight upper bound on the rank of feasible solutions. 

I will also recall related earlier work: we call a feasible semidefinite system well behaved if it has strong duality with its dual for all objective functions. I will present an exact characterization of well behaved  systems, which allows to systematically generate all of them.

In particular, we can systematically generate all linear maps under which the image of the semidefinite cone is closed: this is a problem of independent interest in convex geometry.

The first part of the talk is joint work with Minghui Liu.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hij5r3o0t23smriaao31c0hm18","2015-01-28 18:53:08","2015-03-19 11:15:36"
"2851","3","Artin-Tits Braid groups, low elements and weak order in Coxeter groups","2015-03-09 14:30:00","2015-03-09 15:30:00","SAS 4201","Christophe Hohlweg","http://hohlweg.math.uqam.ca","LaCIM at Universit du Qubec  Montral","Salvatore Stella",,"In this talk we will explain that the question of solving the conjugacy problem in the context of a general Artin-Tits Braid group reveals
strong connections between the weak order of a Coxeter system (W,S), inversion sets of elements of W and small roots. Small roots are the main ingredient introduced by Brink and Howlett in order to build a canonical automaton that recognizes the language of reduced words of elements of W over S. From small roots and inversion sets, we define a new finite class of elements in W called low elements. These low elements are the key to prove that the smallest subset of W containing S, closed under join (for the right weak order) and suffix is finite, and by ricochet that finitely generated Artin-Tits groups have a finite Garside family. Low elements seem rich in further applications in the study of infinite Coxeter groups, which will discuss if time allows.

(Based on joint works with Patrick Dehornoy and Matthew Dyer.)","sstella","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6i0u345erp2bpq77f91mqqb0fc","2015-01-29 14:46:47","2015-02-28 21:59:51"
"2852","46","COLD:  Census of Link Diagrams","2015-03-02 16:00:00","2015-03-02 17:00:00","SAS 2106","Jason Parsley","http://users.wfu.edu/parslerj/","Wake Forest University","Andrew Cooper",,"In this talk we will survey the history of tabulating knots and links, including the errors made along the way.  Until now, computer tabulations have begun by first reducing the (giant) set of all link diagrams, often through highly clever means. Our project, the Census of Link Diagrams (COLD), creates a database of all link diagrams, up to a certain crossing number.  From there, we reduce to a complete tabulation of both prime and composite links.  COLD allows us to answer many diagram-related questions; we will discuss its use in computing unknotting number and knot distances.
 
[COLD is a joint project with Jason Cantarella (UGA), Harrison Chapman (UGA), and Matt Mastin (WFU).]","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/icsv6b0n2gls1gmd9ehcfjc0g8","2015-01-31 21:50:52","2015-02-23 15:33:04"
"2853","14","Departmental Tea and Cookies","2015-02-04 14:30:00","2015-02-04 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/o48cbdnl65najmfolfrq5lk64s","2015-02-02 10:08:35","2015-02-02 10:35:25"
"2854","28","AWM Brown Bag Lunch","2015-02-05 12:15:00","2015-02-05 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/38a8sl8hrqldn1uuh506sef4qk","2015-02-02 10:57:42",NULL
"2855","28","AWM Brown Bag Lunch","2015-02-12 12:15:00","2015-02-12 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/et7pq2ej0084prvja7dhle216s","2015-02-02 10:58:09",NULL
"2856","28","AWM Brown Bag Lunch","2015-02-19 12:15:00","2015-02-19 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1lnev4kckuvkoq5p6gtua85dsg","2015-02-02 10:58:40",NULL
"2857","28","AWM Brown Bag Lunch","2015-02-26 12:15:00","2015-02-26 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/t5qr54d5nnapf3st1ofgnc2ooc","2015-02-02 10:59:05",NULL
"2858","26","TBA","2015-01-26 15:00:00","2015-01-26 16:00:00","SAS 4201","George Lankford",,"NC State","AMGSS",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0q5q8u8ke5pj2n0pu2tlnjmno0","2015-02-02 13:12:44",NULL
"2859","26","An Information Theoretic Approach to Use High-Fidelity Codes to Calibrate Low-Fidelity Codes","2015-02-23 16:00:00","2015-02-23 17:00:00","SAS 4201","Allison Lewis",,"NC State","AMGSS",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nslki8ed06dbhb3qcugio3d1mg","2015-02-02 13:13:37","2015-02-02 13:56:09"
"2860","26","Bayesian model calibration techniques that incorporate mixed effects and model discrepancy","2015-03-02 16:00:00","2015-03-02 17:00:00","SAS 4201","Katie Schmidt",,"NC State","AMGSS",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0u6219gvd4ls8e472mo0gi04rc","2015-02-02 13:14:42","2015-02-24 18:57:06"
"2861","26","Swing-up and Stabilization of an Inverted Pendulum: Real-Time Implementation","2015-03-23 16:00:00","2015-03-23 17:00:00","SAS 4201","Emese Kennedy",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/j8qqerekin2bkssfdg66q8ofv8","2015-02-02 13:15:25","2015-03-19 20:45:57"
"2863","26","Refraction correction for keratometry of the posterior corneal surface using optical coherence tomography imaging","2015-04-06 16:00:00","2015-04-06 17:00:00","SAS 4201","Micaela Mendlow",,"NC State","AMGSS",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/f6mpv5555p5vrs4p0qdbqol2c8","2015-02-02 13:19:33","2015-04-02 15:34:29"
"2864","4","Material transport and pumping across channels at low Reynolds number, in the context of a model for insect respiration","2015-03-04 15:00:00","2015-03-04 16:00:00","SAS 4201","Gregory Herschlag","https://www.math.duke.edu/~gjh/","Duke University",,,"All living organisms of a sufficient size rely on complex systems of tubular networks to efficiently collect, transport and distribute nutrients or waste.  These networks exchange material with the interstitium via embedded channels leading to effective permeabilities across the wall separating the channel interior from the interstitium.  For example, in many invertebrates, respiratory systems are made of complex tracheal systems that branch out through the entire body allowing for passive exchange of oxygen and carbon dioxide.  Certain of these animals utilize various pumping mechanisms that alter the flow of the air or fluid being transported.  Although the net effect of the averaged rates of flow is typically well understood, it is still a largely open problem to understand how, and in what circumstances, pumping enables and enhances the exchange of material across channel walls.  It has been demonstrated experimentally that when certain insects flap their wings, compression of the trachea allow for more efficient oxygen extraction, however it is unclear if this pumping is optimized for flight, oxygen uptake or neither, and understanding this problem quantitatively will shed insight on this biological process as well as potentially inspire novel material extraction techniques in engineering applications.  Insect respiration typically occurs at low Reynolds number and this regime will be the focus of the presentation.  In this talk, I will discuss several new results in fluid flows through channels with permeable membranes, both with static walls and simple pumping dynamics.  The results with be placed in the context of a model for insect respiration, however are be applicable to a broader classification of problems.  The results will then be used to examine the efficacy of pumping as a mechanism for material exchange across channel walls.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/24tfi0gke3drviirhm0j42gdjc","2015-02-03 14:31:50",NULL
"2865","8","Computing Algebraic Matroids","2015-03-31 16:30:00","2015-03-31 17:30:00","SAS 4201","Zvi Rosen","https://math.berkeley.edu/~zhrosen/","UC Berkeley",,,"An affine variety induces the structure of an algebraic matroid on the coordinates of the ambient space. Therefore, algebraic matroids carry important combinatorial information whenever the coordinates have real-world significance. I will introduce these objects, strategies for their computation, and some applications to statistics, biology, and geometry.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0kil1urplfrr445rotu5b73mco","2015-02-03 17:30:14","2015-03-26 09:47:57"
"2866","9","Reconstructing Dynamics using Data Assimilation","2015-02-17 16:15:00","2015-02-17 17:15:00","Cox 306","Franz Hamilton",,"ECE, George Mason University","Alun Lloyd",,"Assimilation of data with models of physical processes is a crucial component of modern scientific analysis. In recent years, nonlinear versions of Kalman filtering have been developed, in addition to methods that estimate model parameters in parallel with the system state.  In the first part of this talk, I will discuss the implementation of a data assimilation algorithm for identifying and tracking connectivity parameters in networks of neurons. Once validated in model, this technique is used to find network connections in neural culture recordings. In the second part of this talk, I propose a substantial extension of the assimilation methodology to deal with the specific case of unmodeled variables, when training data from the variable is available. The method uses a stack of several, nonidentical copies of a physical model to jointly reconstruct the variable in question. I demonstrate the ability of this technique to accurately recover an unmodeled experimental quantity, such as an ion concentration, from a single voltage trace after the training period is completed. The method is applied to reconstruct the potassium concentration in a neural culture from microelectrode array voltage measurements.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/7ef15ilkq11vv1frnhiffl1rkg","2015-02-06 09:02:54",NULL
"2867","9","Parameter Estimation for Dynamical Systems","2015-02-24 16:15:00","2015-02-24 17:15:00","Cox 306","Shelby Stanhope",,"Mathematics, University of Pittsburgh","Alun Lloyd",,"Certain experiments are non-repeatable, because they result in the destruction or alteration of the system under study, and thus provide data consisting of at most a single trajectory in state space. Before proceeding with parameter estimation for models of such systems, it is important to know if the model parameters can be uniquely determined, or identified, from idealized (error free) single trajectory data. For linear models and a class of nonlinear systems that are linear in parameters, I will present several characterizations of identifiability. I will establish necessary and sufficient conditions, solely based on the geometric structure of an observed trajectory, for these forms of identifiability to arise. I will extend the analysis to consider collections of discrete data points, where in certain cases, we can recover the parameters explicitly. I will then examine the role of measurement error in the data and determine regions in the data space which correspond to parameter sets with desired properties, such as model equilibrium stability and sign structure. Lastly, I consider the problem of estimating parameters from distributions in the data space using a Bayesian Inference approach. I propose that estimates of the posterior distribution of parameters obtained through the Metropolis-Hasting algorithm can be improved through the use of a Jacobian prior.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/901hb9got5eqrbmvhl7qeiiv6c","2015-02-06 09:03:51","2015-02-11 00:24:18"
"2868","19",,"2015-02-18 15:00:00","2015-02-18 16:00:00","SAS 2012","Caprice Stanley",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/k0nahco0udud92suifpj1ikun8","2015-02-06 14:49:22",NULL
"2869","3","Quantum groups, quantum cluster algebras, and their categorifications","2015-02-23 14:30:00","2015-02-23 15:30:00","SAS 4201","Dylan Rupel",,"Northeastern University","Salvatore Stella",,"At the heart of the definition of a quantum cluster algebra is a deep conjecture that the recursively, combinatorially defined cluster monomials of a conjectural quantum cluster algebra structure are elements of the (dual) canonical basis of a quantum group.  In this talk I will describe a proof of this dual canonical basis conjecture&quot; in the special case of acyclic, skew-symmetric quantum cluster algebras by relating the categorifications on either side of this picture.","sstella","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/p3lnss19jlu4behu6b97r0k33k","2015-02-08 16:19:01","2015-02-18 20:15:38"
"2870","4","Conference on Knot Theory and Its Applications to Physics and Quantum Computing","2015-01-06 00:00:00","2015-01-09 00:00:00","UT Dallas",,,,,"http://www.utdallas.edu/~mkd034000/QKnots/",,"rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1uqin899uhmo9bgpbu4ugh9ck0","2015-02-08 22:29:13",NULL
"2871","14","Departmental Tea and Cookies","2015-02-11 14:30:00","2015-02-11 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/bl3pj2p8kg63fgju9sbjbo87sk","2015-02-09 11:26:25",NULL
"2872","8","Orthogonal Low Rank Tensor Approximation","2015-02-17 16:30:00","2015-02-17 17:30:00","SAS 4201","Moody Chu","http://www4.ncsu.edu/~mtchu/","NC State",,,"With the notable exceptions of two cases -- that tensors of order 2, namely, matrices, always have best approximations of arbitrary low ranks and that tensors of any order always have the best rank-one approximation, it is known that high-order tensors may fail to have best low rank approximations. When the condition of orthogonality is imposed, even under the modest assumption that only one set of components in the decomposed rank-one tensors is required to be mutually perpendicular, the situation is changed completely -- orthogonal low rank approximations always exist. The purpose of this talk is to discuss the best low rank-approximation subject to orthogonality. The conventional high-order power method is modified to address the orthogonality via the polar decomposition. A synthesis of tools from dynamical system, optimization, algebraic geometry, and numerical analysis is employed to show that for almost all tensors the orthogonal alternating least squares method converges globally.

(This talk showcases an interesting combination of tools mentioned above and should be accessible to graduate students.)","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/d6jm34d8o8bupjouun411i1s0c","2015-02-09 14:04:04","2015-02-16 11:06:42"
"2873","8","Symmetric Tensor Decomposition via Semidefinite Relaxation","2015-03-03 16:30:00","2015-03-03 17:30:00","SAS 4201","Erik Skau","http://www4.ncsu.edu/~ewskau/","NC State",,,"A Gramian decomposable tensor is a symmetric tensor of even order that can be written as a sum of rank one real symmetric tensors. One way to find this minimal rank decomposition is to solve for flat extensions of moment matrices. We consider the semidefinite relaxation of the flat extension problem. It is a natural question to ask when the solution to the relaxation is also a solution to the original problem. We will answer this question by analyzing subresultant matrices of over constrained polynomial systems, and considering their index of regularity.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n8aqkstsfuk1vilias7o8gg7fk","2015-02-09 16:51:37","2015-03-01 20:32:07"
"2874","46","A brief history of unknot detection","2015-02-16 16:00:00","2015-02-16 17:00:00","SAS 2106","POSTPONED Adam Lowrance","http://faculty.vassar.edu/adlowrance/","Vassar College","Radmila Sazdanovic",,"In this talk, we discuss various methods to detect the unknot including Hakens normal surface theory method, Dynnikovs grid diagram method, and various knot homology unknot detectors.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6dsl7m4660epn8jianjdph0m5o","2015-02-09 22:37:51","2015-02-15 18:17:24"
"2875","4","Study on the modeling and dynamics on the liquid filled system","2015-03-05 15:00:00","2015-03-05 16:00:00","SAS 2102","Baozeng Yue",,"Beijing Institute of Technology",,,"In this talk, I will present our recent work of the liquid filled system. Our research is mainly concerned on liquid sloshing dynamics and its application in spacecraft engineering. The prediction and dynamical modeling of the contained liquid motion with free surface (or liquid sloshing) is essential to the development of control system for spacecraft and fluid management in micro-gravity. Numerical methods are too computationally demanding for spacecraft attitude and orbit controller design and performance evaluation, and, moreover, the validation of them remains challenging. We use the traditional well-known lumped pendulum and mass-spring models and liquid sloshing in tanks of different shapes and carried on the further studies on modeling of multi-body coupled system, dynamics and control of spacecrafts with flexible appendage and fuel slosh. In the second part of the talk, I will present our recent work on the modeling of the large-amplitude liquid sloshing and its spacecraft engineering application.The important modifications are performed on the previous pulsating ball model (PBM) is studied in this paper. The PBM is newly - developed mechanical equivalent model to describe the dynamics of spacecraft with a partially filled tank. The modification is carried on to precisely evaluate the capillary effects on the constitution of the normal force, which results from one of the basic features of the slug, specifically, a lower limit of size corresponding to an intrinsic part of capillary energy. These two modifications are expected to be critical in developing a more sophisticated PBM to duplicate the dynamics of liquid motion. The numerical simulation results from the modified PBM are compared with those from not-modified model and the revealed experimental results and thus the validity of the improved pulsating ball model is confirmed.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0s0mkvcfek7grc4ehsl9khkppo","2015-02-10 14:31:39","2015-02-26 11:44:50"
"2876","24","Valentines Day Cookie Contest","2015-02-13 11:15:00","2015-02-13 13:00:00","SAS 4104",,,,,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/503pv3f84smnstm3k3fi92d4pg","2015-02-11 11:21:37",NULL
"2877","46","On the Geometry of the Universe","2015-03-23 16:00:00","2015-03-23 17:00:00","SAS 2106","Hubert Bray","http://fds.duke.edu/db/aas/math/faculty/bray/","Duke University","Andrew Cooper",,"The Einstein-Hilbert action of general relativity was discovered by the great mathematician Hilbert who was also the first to publish the correct version of the Einstein Equation.* These facts demonstrate how there is no sharp dividing line between geometry and physics. Well summarize the role mathematics has played in understanding the large-scale structure of the universe to date, and then highlight the mysteries that exist today. Well also explain why what physicists call dark matter could just as easily - if not more properly - be called large-scale unexplained curvature of the universe.

*Einstein and Hilbert discovered the Einstein Equation independently. Einsteins first paper on general relativity captured the essence of general relativity, which is that matter curves spacetime, but did not have the right equation, though it was close. Hilbert does get sole credit for the action of general relativity, though.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/e667it3f14ud0p6iahf0f09g08","2015-02-11 12:46:25","2015-03-18 01:46:47"
"2878","6","Modeling and Simulation of Filtration and Separation Environments","2015-03-24 15:00:00","2015-03-24 15:50:00","SAS 4201","Lea Jenkins","http://www.math.clemson.edu/~lea/","Clemson","NA Seminar",,"Filtration and separations processes are ubiquitous in our everyday

lives.  They are involved in a wide range of production environments,

including polymer fiber production and production of

biopharmaceuticals.  Filtration devices provide us access to clean

water, and they help our car engines run smoothly.  Our body also

uses filtration processes to efficiently trap and remove

impurities.  In this talk, I will present an overview of filtration

processes used in the polymer fiber and biopharmaceutical industries,

including a synopsis of several mathematical problems that arise in

the context of modeling these processes.  I will also describe

theoretical work and numerical results associated with our efforts to

develop simulation frameworks for engineers interested in optimizing

their manufacturing capabilities based on effective filtration.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/87urcqld82n2gjcgn3qallj7lk","2015-02-11 12:53:17","2015-02-24 12:29:53"
"2879","14","Departmental Tea and Cookies","2015-02-20 15:00:00","2015-02-20 15:30:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/0voc25014r4tf6jvduhc6s374c","2015-02-16 09:54:20",NULL
"2880","8","Semidefinite characterization of sum-of-squares cones in algebras","2015-04-07 16:30:00","2015-04-07 17:30:00","SAS 4201","David Papp","http://www4.ncsu.edu/~dpapp/","NC State",,,"The cone of sum-of-squares polynomials are popular substitutes for nonnegative polynomials in computational real algebraic geometry and polynomial optimization, due to their &quot;tractability&quot; via their semidefinite programming representation. More generally, sum-of-squares functions can be defined analogously, and it is easy to show that these are also tractable subsets of nonnegative functions. In this talk, we take this generalization a step further, and consider sum-of-squares cones defined with respect to an (almost) arbitrary multiplication. We show that these cones (and their dual cones) also admit an analogous semidefinite representation. This allows the construction of a host of sum-of-squares cones, and shows that many well-known (but not obviously tractable) cones are sum-of-squares cones. We shall briefly investigate the relationships between the algebraic properties of the multiplication and the geometric properties of the cone, and discuss some applications ranging from geometric to combinatorial optimization problems. Joint work with Farid Alizadeh.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dl37esuk79i2of2itrecn5ames","2015-02-16 11:33:43","2015-03-31 13:31:08"
"2881","2","Positivity and Analysis on the Cone with Applications to Data Science","2015-02-20 11:00:00","2015-02-20 12:00:00","SAS 4201","Bala Rajaratnam",,"Stanford University","Ralph Smith",,"Positive definite matrices arise naturally in many areas within mathematics and also feature extensively in scientific applications. They can also be interpreted as covariance or correlation matrices, and thus represent dependencies among components of a random vector.  In modern high-dimensional applications, a common approach to finding sparse positive definite or correlation matrices is to threshold their small off-diagonal elements. This thresholding, sometimes referred to as hard-thresholding, sets small elements to zero. Thresholding has the attractive property that the resulting matrices are sparse, and are thus easier to interpret and work with. In many applications, it is often required, and thus implicitly assumed, that thresholded matrices retain positive definiteness. We formally investigate the  mathematical properties of positive definite matrices which are thresholded. Questions on positivity have a long and rich tradition in mathematics, starting with the work of Rudin, Schoenberg, Polya, Karlin and others. We undertake a detailed study of regularization approaches which operate on the cone. Finally, we obtain a full characterization of general maps which preserve positivity when applied to off-diagonal elements of a positive definite matrix, thereby extending previous work by Schoenberg and Rudin. (Joint work with D. Guillot and A. Khare)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/pch065l2bf0mk9utg5ghm9snsk","2015-02-16 11:37:11","2015-02-18 09:55:31"
"2882","8","Optimal ate pairing over cyclotomic family of elliptic curves","2015-04-21 16:30:00","2015-04-21 17:30:00","SAS 4201","Eunjeong Lee",,"NC State",,,"An ate pairing is a certain bilinear map over elliptic curves, which has an application in cryptography. One of the main challenges is to find an &quot;optimal&quot; ate pairing for a given elliptic curve. Due to its importance, there has been intensive research on this challenge.

In this talk, we will provide a simple/explicit formula for an optimal ate pairing for a cyclotomic family of elliptic curves (curves constructed from cyclotomic polynomials). The simplicity of the formula allows us to analyze the efficiency of the pairing.

The talk will be accessible to wide audience. It will consist of the following:
1) What is a Public Key Cryptosystem (PKC)?
2) What is a pairing and how is it used in PKC?
3) What is an ate pairing on elliptic curve?
4) What is a cyclotomic family of elliptic curves? 

The talk will end with a description of our main contribution: a simple/explicit formula for optimal ate pairing over cyclotomic family of elliptic curves.

This is joint work with Hoon Hong (NCSU) and Hyang-Sook Lee (Ewha Womans University).","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/03fs1mi9fq0756lfl7s5f85ns4","2015-02-16 18:07:08","2015-04-02 20:37:24"
"2884","9","Reconstructing Dynamics using Data Assimilation","2015-02-18 11:30:00","2015-02-18 12:30:00","Cox 306","Franz Hamilton",,"George Mason University",,,"Assimilation of data with models of physical processes is a crucial component of modern scientific analysis. In recent years, nonlinear versions of Kalman filtering have been developed, in addition to methods that estimate model parameters in parallel with the system state. In the first part of this talk, I will discuss the implementation of a data assimilation algorithm for identifying and tracking connectivity parameters in networks of neurons. Once validated in model, this technique is used to find network connections in neural culture recordings. In the second part of this talk, I propose a substantial extension of the assimilation methodology to deal with the specific case of unmodeled variables, when training data from the variable is available. The method uses a stack of several, nonidentical copies of a physical model to jointly reconstruct the variable in question. I demonstrate the ability of this technique to accurately recover an unmodeled experimental quantity, such as an ion concentration, from a single voltage trace after the training period is completed. The method is applied to reconstruct the potassium concentration in a neural culture from microelectrode array voltage measurements.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/lf470oj7e6evlcudvc2csd0f3k","2015-02-17 19:34:49",NULL
"2885","8","Orthogonal Low Rank Tensor Approximation","2015-02-19 16:30:00","2015-02-19 17:30:00","SAS 4201","Moody Chu","http://www4.ncsu.edu/~mtchu/","NC State",,,"With the notable exceptions of two cases -- that tensors of order 2, namely, matrices, always have best approximations of arbitrary low ranks and that tensors of any order always have the best rank-one approximation, it is known that high-order tensors may fail to have best low rank approximations. When the condition of orthogonality is imposed, even under the modest assumption that only one set of components in the decomposed rank-one tensors is required to be mutually perpendicular, the situation is changed completely -- orthogonal low rank approximations always exist. The purpose of this talk is to discuss the best low rank-approximation subject to orthogonality. The conventional high-order power method is modified to address the orthogonality via the polar decomposition. A synthesis of tools from dynamical system, optimization, algebraic geometry, and numerical analysis is employed to show that for almost all tensors the orthogonal alternating least squares method converges globally.

(This talk showcases an interesting combination of tools mentioned above and should be accessible to graduate students.)","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n1fcbvnu8qm1fk1tk6n315c95g","2015-02-17 20:11:12","2015-02-17 20:12:00"
"2886","4","Nonlinear Wave-Plate Models of Aeroelastic Flutter","2015-04-08 15:00:00","2015-04-08 16:00:00","SAS 4201","Justin Webster",,"NC State",,,"Flutter is an aeroelastic instability which occurs when aerodynamic loading excites the natural modes of an elastic structure. Studies of panel, wing, and flag flutter are prevalent in the engineering literature of the last 50 years. The canonical model in aeroelasticity couples a thin plate or beam to a perturbed wave equation (potential flow) in the over-body half space. Well-posedness and global attraction properties for this model (in the absence of dissipation mechanisms) have been established recently. The results use of state-of-the art techniques for von Karman equations, PDEs with delay, and dissipative dynamical systems. Here we present the most up-to-date well-posedness and stabilization results for the full flow-plate dynamics. We will address panel flutter directly from the PDE model, and corroborate physical observations that panel flutter does not occur in subsonic flows. We will also discuss various other configurations and related models, including panels with thermoelastic considerations, and the flutter problem with free-plate boundary conditions.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ccdi7d6bnmp1695i0u9rbpa17g","2015-02-18 11:54:23","2015-04-05 12:28:13"
"2887","15","CANCELLED: SIAM meeting","2015-02-24 12:15:00","2015-02-24 13:15:00","POE 517","Lea Jenkins",,"Clemson",,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/blfran30rk7589hr65uncldoc0","2015-02-19 08:10:44","2015-02-24 10:17:56"
"2888","4","Hamels Formalism for Infinite-Dimensional Mechanical Systems","2015-03-18 15:00:00","2015-03-18 16:00:00","SAS 4201","Dmitry Zenkov",,"NC State",,,"Splitting up the configuration and velocity measurements was pioneered by Euler in 1750s in his study of the dynamics of rigid body and fluid. This use of nonmaterial velocity influenced greatly the development of mechanics. In 1904, Hamel extended this approach from the rigid body setting to arbitrary mechanical systems with finite number of degrees of freedom. This talk will review recent development of Hamels ideas in relation to continuum mechanics.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8hcjt07n3817kiljrm1jaore4s","2015-02-21 12:08:17","2015-03-04 09:40:54"
"2889","14","Graduate Recruitment Weekend Event","2015-02-27 13:30:00","2015-02-27 17:00:00","SAS 4201",,,,"Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/bmcag2gv248qfvugjmfkcjnlvg","2015-02-22 20:43:37","2015-02-22 20:47:17"
"2890","14","Graduate Recruitment Weekend Event","2015-02-28 10:15:00","2015-02-28 16:15:00","SAS 4201",,,,"Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/snm1traujp2m34g69uj4k4ptd0","2015-02-22 20:44:51","2015-02-22 20:47:43"
"2891","19","Characterizing solvability and supersolvability in Leibniz algebras","2015-03-04 15:00:00","2015-03-04 16:00:00","SAS 2102","Bethany Turner",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6ahh1cd8hp2dk4ocnavipk7v3o","2015-02-25 12:21:17","2015-03-04 11:21:17"
"2893","21","MoSAIC: Mathematics of Science, Art, Industry, Culture","2015-03-27 10:00:00","2015-03-27 19:30:00","SAS Hall, NC State",,,,,"https://www.math.ncsu.edu/events/Mosaic.php","A festival celebrating the connections between mathematics and the arts.
Free and open to the public, middle-school to adult.

Friday, March 27, 10 a.m. to 7:30 p.m., and Saturday, March 28, 10
a.m. to 5 p.m. SAS Hall

Hands-on workshops, lectures, a mathematical art exhibit, short films,
and an area for informal exchange.

Please register at http://go.ncsu.edu/mosaic","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/bbl2k2malms2qic3tsu0bilg98","2015-02-27 00:56:46","2015-03-02 10:22:18"
"2894","21","MoSAIC: Mathematics of Science, Art, Industry, Culture","2015-03-28 10:00:00","2015-03-28 17:00:00","SAS Hall, NC State",,,,,"https://www.math.ncsu.edu/events/Mosaic.php","A festival celebrating the connections between mathematics and the arts.
Free and open to the public, middle-school to adult.

Friday, March 27, 10 a.m. to 7:30 p.m., and Saturday, March 28, 10
a.m. to 5 p.m.
SAS Hall

Hands-on workshops, lectures, a mathematical art exhibit, short films,
and an area for informal exchange.

Please register at http://go.ncsu.edu/mosaic","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/or8nmn0lt2il113e02dfa8hue8","2015-02-27 00:58:08","2015-03-02 10:22:23"
"2895","24","Belated Pi Day Celebration","2015-03-16 11:30:00","2015-03-16 13:00:00","SAS 4104",,,,"MGSA","http://www.probability.ca/jeff/writing/PiInstant.html",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/us8m3pvb5hmams9ladhe9uic9s","2015-02-27 11:50:40",NULL
"2896","15","SIAM Meeting and Cookies from Insomnia","2015-03-03 15:00:00","2015-03-03 16:00:00","SAS 2102","Dr. Berton Earnshaw","https://savvysherpa.com","SavvySherpa",,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/pqlvs2ska1i64gs1njo0mpm670","2015-03-02 06:53:26","2015-03-03 11:24:33"
"2897","38","High-Order Accurate Solutions to the Helmholtz Equation in the Presence of Boundary Singularities","2015-02-27 11:00:00","2015-02-27 12:30:00","SAS 3282","Darrell Britt",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ema8at9fghor8bbvq6qracfpl0","2015-03-02 09:19:12",NULL
"2898","38","Positive Root Bounds and Root Separation Bounds - advised by Hoon Hong","2015-03-16 09:00:00","2015-03-16 10:30:00","SAS 3282","Aaron Herman",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ugq8cidlrfqpcuk52ic8ruqfoc","2015-03-02 09:21:48",NULL
"2899","38","Verification techniques for parameter selection and Bayesian model calibration presented for an HIV model - advised by Ralph Smith","2015-03-02 10:00:00","2015-03-02 11:30:00","SAS 3282","Mami Wentworth",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/t1g7ppcjm2arepbfqp7pu72leg","2015-03-02 09:24:17",NULL
"2900","14","Departmental Tea and Cookies","2015-03-04 14:30:00","2015-03-04 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/mkfpq5qugijincuk5kmc9glrm0","2015-03-02 10:18:21",NULL
"2901","38","Algorithms and applications in numerical elimination theory - advised by Jon Hauenstein","2015-04-24 15:30:00","2015-04-24 17:00:00","SAS 4201","Noah Daleo",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/fc8lhjdnlb9mrbbn91ef7m02uo","2015-03-02 13:27:49",NULL
"2902","28","AWM Brown Bag Lunch","2015-03-05 12:15:00","2015-03-05 13:15:00","3rd floor grad lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/s8mnp46n9hrprcv9vr5p7da4v0","2015-03-02 23:47:05",NULL
"2903","8","Twisted Matrix Factorizations","2015-03-17 16:30:00","2015-03-17 17:30:00","SAS 4201","Frank Moore","http://users.wfu.edu/moorewf/","Wake Forest University",,,"The notion of a matrix factorization was introduced by Eisenbud in the commutative case in his study of bounded (periodic) free resolutions over complete intersections. Since then, matrix factorizations have appeared in a number of applications. We extend the notion of (homogeneous) matrix factorizations to regular normal elements of connected graded algebras over a field. Examples using the NCAlgebra package for Macaulay2 will be given. This is joint work with Tom Cassidy, Andy Conner and Ellen Kirkman.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9sinuu2bklh0k45m50kcsfenug","2015-03-03 09:17:40","2015-03-03 10:28:34"
"2904","4","Kinetic flocking models and phase transitions","2015-04-01 15:00:00","2015-04-01 16:00:00","SAS 4201","Alethea Barbaro","http://www.case.edu/artsci/math/barbaro/","Case Western Reserve University","Alina Chertock",,"Flocking models abound in the recent mathematical and scientific literature.  These models can be applied to social animals which exhibit collective behavior and have been applied to the movement of fish, birds, and even occasionally to humans.  The most common of these models are the Vicsek model and the Cucker-Smale model, which can both be studied at the microscopic, kinetic, and hydrodynamic levels.  In this talk, we will begin with an application of a microscopic flocking model to a species of fish in the North Atlantic.  We will then continue on to examine similar models at the kinetic and hydrodynamic scales, showing that there is a phase transition between a polarized migratory phase and a disorganized swarming phase as the magnitude of noise varies.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o0v8lvnj2ldv9frlhabpi8uq88","2015-03-04 13:21:01","2015-03-19 18:49:57"
"2905","3","Complete branching rules","2015-03-23 14:30:00","2015-03-23 15:30:00","SAS 4201","Ricky Liu",,"NC State",,,"Given an arbitrary diagram of boxes, one can define a representation of the symmetric group called a Specht module. For partitions, the corresponding Specht modules are irreducible, and their restrictions satisfy a simple branching rule. We will define an analogous notion of (complete) branching for arbitrary Specht modules and give a combinatorial criterion for when a diagram admits a complete branching rule. We will also relate this notion to questions in combinatorics, algebra, and geometry.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2ggifjefe7vp1006diprqvn4ig","2015-03-04 16:14:14","2015-03-16 15:11:23"
"2906","38","Topics in randomized numerical linear algebra - advised by Ilse Ipsen","2015-04-28 14:00:00","2015-04-28 15:30:00","SAS 3282","John Holodnak",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/n7mjbnl1t65mtfnug8m9s1i8d0","2015-03-05 11:16:30",NULL
"2907","28","AWM Brown Bag Lunch","2015-03-19 12:15:00","2015-03-19 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/vsbqjleaug0npcfnacp9v9acoc","2015-03-05 13:55:32",NULL
"2908","28","AWM Brown Bag Lunch","2015-03-26 12:15:00","2015-03-26 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/pc0776vqsnq109lt4juo9pq2rs","2015-03-05 13:56:10",NULL
"2909","28","AWM Brown Bag Lunch","2015-04-02 12:15:00","2015-04-02 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2s6cbjilonf90a6i053hld0ne4","2015-03-05 13:56:41",NULL
"2910","28","Sonia Kovalevsky Day","2015-04-18 08:00:00","2015-04-18 12:00:00","SAS Hall",,,,,,"Sonia Kovalevsky was the first major female mathematician and, in honor of her, schools across the nation host an annual SK Day to encourage younger females to gain more interest in the mathematical sciences.  This is NCSUs 4th Annual SK Day and will feature workshops geared towards 7th and 8th grade girls in graph theory, game theory, and the one-cut theorem.","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/u1peg01t7aqlni0lre8v5kv7g4","2015-03-05 14:00:14",NULL
"2911","38","Approximate solutions of the Landau-Lifshitz equation - advised by Mark Hoefer","2015-05-05 10:00:00","2015-05-05 11:30:00","SAS 3282","Lake Bookman",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/npjr3gt8cu2tgkp30adgn55cjs","2015-03-09 09:29:25","2015-03-09 09:30:08"
"2912","38","Orbits of minimal parabolic k-subgroups acting on symmetric k-varieties - advised by Loek Helminck","2015-03-25 14:30:00","2015-03-25 16:00:00","SAS 3282","Mark Hunnell",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/3269ved4qecjkaebj0dod12lss","2015-03-09 09:32:57","2015-03-09 09:33:31"
"2913","4","Coupling arterial-venous hemodynamics","2015-04-22 15:00:00","2015-04-22 16:00:00","SAS 4201","Muhammad Qureshi","https://www.sites.google.com/a/ncsu.edu/muqureshi/home","NC State",,,"Most 1D fluid dynamical network models predict blood flow and pressure in the large arteries by truncating the arterial tree after a few generations. The rest of the arterial system is then accounted via an outflow boundary condition applied at the terminal branches. Examples of such boundary conditions are the 0D Windkessel models, which lump the remainder of the vasculature, and the 1D binary structured-tree models, which model the small arteries and arterioles as a distributed network. The arterial structured tree approach allows us to account for the effects of wavepropagation beyond the truncted large arteris but due to its truncation after certain number of generations, it lacks any account of venous hemodynamics.
In this talk, a structured-tree based model will be presented that allows prediction of blood flow and pressure in the connected arterial and venous system. This is done by developing an algorithm to establish the arterial venous coupling using pairs of structured-trees connected at their smallest (terminal) branches. A semi-analytical approach based on a linearized version of the viscous axisymmetric Navier-Stokes equations and a fast recurrence relation is used to derive a total admittance matrix for the connected structured-trees in the frequency domain. In the time domain, this provides the matching condition linking pressures and volume fluxes between terminal large arteries and the corresponding large veins. Implimentation of this matching condition in a patient specific 1D network model of pulmonary circulation has shown to improve the prediction of pressure and flow in the large arteries and veins.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5gmj3diabj9offk69je3o8h93s","2015-03-11 17:21:02","2015-04-20 11:01:29"
"2915","3","Algebraic graph limits","2015-04-06 14:30:00","2015-04-06 15:30:00","SAS 4201","Patrik Noren",,"NC State",,,"The theory of graph limits associates random graph models to symmetric measurable functions on the unit square. We investigate what happens when these functions are polynomials. For low degree polynomials the models appearing are familiar and important, for example preferential attachment and Erdos-Renyi. The higher degree polynomials are also useful as any graph limit can be arbitrarily well approximated by a polynomial. We show that this setup could be useful in applications: To determine the parameters of an algebraic graph limit that fits observed data best one can use numerical algebraic geometry efficiently.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ta72b829v7ueomr33vb8rr8jt4","2015-03-16 15:08:52","2015-03-24 11:57:24"
"2918","38","Swing-up and stabilization of an inverted pendulum: real-time implementation - advised by Hien Tran","2015-03-25 11:30:00","2015-03-25 13:00:00","SAS 3282","Emese Kennedy",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/8lb9bc8dst610monb75q8vfa90","2015-03-18 10:01:38","2015-03-18 10:02:53"
"2920","3","Boson-fermion correspondences of types B and D and multi-local Virasoro representations","2015-04-13 14:30:00","2015-04-13 15:30:00","SAS 4201","Iana Anguelova","https://math.cofc.edu/about/faculty-staff-listing/anguelova-iana.php","College of Charleston",,,"The boson-fermion correspondences are amazing phenomena on the nexus of several areas in mathematical physics and representations theory. On a basic level  each relates a bosonic Fock space (a representation of an infinite dimensional Heisenberg Lie algebra) and a fermionic Fock space (a representation of an infinite dimensional Clifford algebra).  In this talk we will discuss how the boson-fermion correspondences of types A, B, C and D arise from the point of view of  representations of the 4 doubly-infinite rank Lie algebras $a_{\infty}$, $b_{\infty}$, $c_{\infty}$ and $d_{\infty}$. We will  outline  the boson-fermion correspondences of type B (relatively longer and  better known, see Date-Jimbo-Kashiwara-Miwa) and type  D (quite new, see IA); their few similarities and many differences.   As any true boson-fermion correspondence,  the correspondences of types B and D are isomorphisms of certain chiral algebras (in these cases  twisted vertex algebras).  We show that these twisted vertex  algebras are &quot;conformal&quot;, i.e., they possess Virasoro fields, which  although being  2-point-local (with singularities both at $z=w$ and $z=-w$), have modes comprising the actual Virasoro algebra, not a 2-point Virasoro algebra.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jnsdq5h084mvo8gkfvtf39bieo","2015-03-18 12:50:48","2015-03-31 22:33:35"
"2922","14","Departmental Tea and Cookies","2015-03-18 14:30:00","2015-03-18 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/94p7gts605p40su45h4rlb46d8","2015-03-18 14:49:02",NULL
"2924","21","4th Annual Sonia Kovalevsky Day","2015-04-18 08:00:00","2015-04-18 12:00:00","SAS Hall",,,,,"https://www.math.ncsu.edu/forms/AWM/app/index.php","Register at https://www.math.ncsu.edu/forms/AWM/app/index.php","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6rq1gje3655b53k9kit99on3k0","2015-03-18 15:51:15","2015-03-18 15:51:54"
"2927","14",,"2015-04-11 12:00:00","2015-04-11 15:30:00","Raleigh Pullen Park, Shelter #5",,,"Spring Math Department Picnic",,,"Mark your calendars:  This semester we will have a spring departmental picnic on Saturday, April 11 in Pullen Park.  The department will provide funds for basic picnic supplies (burgers, veggie burgers, hot dogs, and accompaniments), and faculty, staff and graduate students will be encouraged to sign up to bring potluck items or help with setup, cleanup, and grilling.  

Saturday, April 11, 2015,  12 PM - 3:30 PM
Pullen Park, Shelter #5

Next week we will send an online signup sheet for you to RSVP and signup to bring something or help out with setup, cleanup, and grilling.  So keep your eyes open for this. 

Looking forward to enjoying the warmer weather with you,","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/gusmn6irpfrk0ga2cdraje9kck","2015-03-19 10:00:42",NULL
"2930","15","SIAM meeting and Pizza","2015-03-24 12:15:00","2015-03-24 13:15:00","POE 517","Dr. Lea Jenkins","http://www.math.clemson.edu/~lea/","Clemson",,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/jf592pose6r9eog4utctm4cic0","2015-03-19 11:24:31","2015-03-24 09:54:52"
"2933","14","Departmental Tea and Cookies","2015-03-24 14:30:00","2015-03-24 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ekn8qp5i0mifk1v17corq02bac","2015-03-19 14:00:00","2015-03-23 09:41:15"
"2936","14","Departmental Tea and Cookies","2015-04-01 14:30:00","2015-04-01 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/3t45nf1g9kvj656uorkplp1us0","2015-03-19 14:00:35",NULL
"2939","14","Departmental Tea and Cookies","2015-04-08 14:30:00","2015-04-08 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/00m19b4n62hriq6t2nnn7n48v8","2015-03-19 14:01:35",NULL
"2942","3","Graph coloring and the total Betti number","2015-04-20 14:30:00","2015-04-20 15:30:00","SAS 4201","Alex Engstrom","http://math.aalto.fi/~alex/index.php","Aalto University, Finland",,,"The total Betti number of the independence complex of a graph is an intriguing graph invariant. Kalai and Meshulam have raised the question on its relation to cycles and the chromatic number of a graph, and a recent conjecture on that theme was proved by Bonamy, Charbit and Thomasse. We show an upper bound on the total Betti number in terms of the number of vertex disjoint cycles in a graph. The main technique is discrete Morse theory and building poset maps. Ramanujan graphs with arbitrary chromatic number and girth log(n) is a classical construction. We show that any subgraph of them with less than n^0.003 vertices have smaller total Betti number than some planar graph of the same order, although it is part of a graph with high chromatic number.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/p5f7kloj6lcmei670id8em9oi0","2015-03-20 16:23:05","2015-03-23 11:24:16"
"2945","3","Flat groups and graphs: the unreasonable connectedness of mathematics","2015-03-24 15:00:00","2015-03-24 16:00:00","SAS 2102","Jacqui Ramagge",,"University of Wollongong, Australia",,,"This will be a colloquium-style talk which should be accessible to graduate students. Rather than try to tell you exactly what is in it and scare you off by sounding too technical, let me just say it will be about trying to use intuitions from linear algebra in group theory even though there is no linear space in sight.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8sqv3n4j8o6do4ig0draqv5p7k","2015-03-20 16:28:32","2015-03-23 07:24:05"
"2948","3","Moy-Prasad filtrations and flat G-bundles on curves","2015-03-30 14:30:00","2015-03-30 15:30:00","SAS 4201","Daniel Sage","https://www.math.lsu.edu/~sage/","Louisiana State University",,,"In this talk, I describe a new approach to the study of flat G-bundles
on curves (for complex reductive G) using methods of representation
theory.  This approach is based on a geometric version of the
Moy-Prasad theory of minimal K-types (or fundamental strata) for
representations of p-adic groups.  In the geometric theory, one
associates a fundamental stratum--data involving an appropriate
filtration on the loop algebra--to a formal flat
G-bundle. Intuitively, this stratum plays the role of the &quot;leading
term&quot; of the flat G-bundle and can be used to define its slope.  I
will explain how these ideas can be used to construct well-behaved
moduli spaces of irregular singular flat G-bundles on P^1 and to
realize the isomonodromy equations as an explicit integrable system on
these moduli spaces.  Time permitting, I will discuss some
applications (and potential applications) to the geometric Langlands
program, where (unlike the classical situation), fundamental strata
can be associated to objects on both the Galois and automorphic side
of the correspondence.  This is joint work with C. Bremer.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o6jbr9urpvtp295e32a2tlj0uc","2015-03-21 14:36:21","2015-03-23 07:12:30"
"2951","7","A New Proof for van den Berg - Kesten Inequality","2015-04-01 16:00:00","2015-04-01 17:00:00","SAS 4201","Min Kang","http://www.math.ncsu.edu/~mkang2","NC State ","Tao Pang and Min Kang",,"We prove the van den Berg - Kesten inequality which was conjectured by J. van den Berg and H. Kesten in 1985 and remained to be one of the most perplexing problems in Probability theory for many years until D. Reimer provided a proof in 2000 which was the only proof up to now, though it is abstract and algebraic in nature.  Our proof is simple and very different from that of Reimers.  We also clarify a case when the inequality actually achieves equality.  This is a joint work with R. Hartwig.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4ar5r90v0vdfpl8rjkiv9fjgao","2015-03-23 10:23:37","2015-03-23 10:32:21"
"2954","38","Nonlinear filtering problems for systems governed by PDEs - advised by Kazi Ito","2015-04-23 14:00:00","2015-04-23 15:30:00","Poe 517","Melissa Ngamini",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/6unol38e48p5gbcrmt04ul42eg","2015-03-24 09:05:32","2015-04-23 10:44:30"
"2957","38","Classifying the fine structures of involutions acting on root systems - advised by Loek Helminck","2015-05-07 14:00:00","2015-05-07 15:30:00","SAS 382","Samuel Ivy",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/mntjhdq9anj3i3k0vbqkugbej4","2015-03-24 13:18:34",NULL
"2960","46","Knots Transverse to a Vector Field","2015-03-30 16:00:00","2015-03-30 17:00:00","SAS 2106","Patricia Cahn","http://hans.math.upenn.edu/~pcahn/","University of Pennsylvania","Radmila Sazdanovic",,"We study knots transverse to a fixed vector field V on a 3-manifold M up to the corresponding isotopy relation. We show this classification is particularly simple when V is the co-orienting vector field of a tight contact structure, or when M is
irreducible and atoroidal. We also apply our results to study loose Legendrian knots in overtwisted contact manifolds,and generalize results of Dymara and Ding-Geiges.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/m0mtidfdgigrr89jqnouuh0308","2015-03-26 15:20:15",NULL
"2963","26","Testing Goodness-of-fit and the Equality of Distributions using Energy Statistics","2015-03-30 16:00:00","2015-03-30 17:00:00","SAS 4201","Kayla Coleman",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/r1jei4hj170k3pdg8i4iokaung","2015-03-26 16:03:32",NULL
"2966","19",,"2015-04-01 15:00:00","2015-04-01 16:00:00","SAS 2102","Tiffany Burch",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/7jdntu9a05pqsvh68t37kmp7fk","2015-03-30 12:48:09",NULL
"2969","38","Conjugacy classes of maximal k-split tori invariant under an involution of SL(n,k) - advised by Loek Helminck","2015-05-05 10:00:00","2015-05-05 11:30:00","SAS 4201","Sarah Mason",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/2i1j3852jg02sde5nqqv10ilhc","2015-03-31 10:18:47","2015-03-31 11:23:16"
"2972","38","Additional Symmetries of the Extended Toda Hierarchy - advised by Bojko Bakalov","2015-06-16 14:00:00","2015-06-16 15:30:00","SAS 3282","William Wheeless",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/2870mtsj082fcojeueo9bg2ucs","2015-03-31 10:26:04","2015-03-31 10:26:47"
"2975","38","Sequential programming for PDE constrained optimization - advised by Kazi Ito","2015-07-14 13:00:00","2015-07-14 14:30:00","SAS 3282","Brett Coonley",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/s4h6huck09bv2jl30nlqsagee0","2015-04-02 12:56:49",NULL
"2978","7","Moderate Deviation Principles for Stochastic Dynamical Systems","2015-04-08 16:00:00","2015-04-08 17:00:00","SAS 4201","Amarjit Budhiraja",,"University of North Carolina at Chapel Hill","Tao Pang and Min Kang",,"We present Moderate Deviation Principles for stochastic dynamical systems with small noise that is given in terms of Poisson random measures (PRM) and finite or infinite dimensional Brownian motions (BM). As applications we consider a family of stochastic partial differential equations with jumps and large collections of weakly interacting countable state Markov processes. Proofs rely on certain variational representations for expected values of nonnegative functionals of PRM and BM.","mkang2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2f0badb0ro24n2897is5rdeh2s","2015-04-05 13:10:12",NULL
"2981","46","Quantum knot invariants and Howe dualities","2015-04-06 16:00:00","2015-04-06 17:00:00","SAS 2106","David Rose","http://www-bcf.usc.edu/~davidero/","University of Southern California","Radmila Sazdanovic",,"Well review the quantum sl_n knot invariants and their description via MOY calculus, as well as work of Cautis-Kamnitzer-Licata-Morrison showing how these invariants arise naturally from a duality between sl_n and sl_m called skew Howe duality. Well then discuss work (joint with Aaron Lauda and Hoel Queffelec) categorifying this result to give elementary constructions of Khovanov and Khovanov-Rozansky knot homology. Time permitting, well also discuss work (joint with Daniel Tubbenhauer) relating symmetric Howe duality to the colored Jones polynomial, and giving a new diagrammatic method for computing this invariant.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/780utvj2agefqt7q94ljn80gq0","2015-04-05 16:37:39",NULL
"2984","28","AWM Brown Bag Lunch","2015-04-09 12:15:00","2015-04-09 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/hoks1k5ot07ojv5qjd4v3lfotg","2015-04-07 09:39:01",NULL
"2987","28","AWM Brown Bag Lunch","2015-04-16 12:15:00","2015-04-16 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/bmnubdt0uaf2s9sc96tc0p98ds","2015-04-07 09:39:33",NULL
"2990","28","AWM Brown Bag Lunch","2015-04-23 12:15:00","2015-04-23 13:15:00","3rd floor grad student lounge",,,,,,,"cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/5cvj23fj13ltfq5dlerd66b8cc","2015-04-07 09:40:00",NULL
"2993","38","An augmented iterative algorithm for elliptic interface problems with variable and discontinuous coefficients - advised by Zhilin Li","2015-04-23 11:15:00","2015-04-23 12:45:00","SAS 3282","Guanyu Chen",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/cst5s165ql7mkdjf6gged8mqis","2015-04-09 15:00:42",NULL
"2996","11","Does Arbitrage Exist in Closed-End Fund? Embedded Option and Empirical Studies","2015-04-15 16:00:00","2015-04-15 17:00:00","SAS 4201","Yawei Yao",,"School of Finance and Business, Shanghai Normal University","Tao Pang",,"Although the market price of a Closed-End Fund (CEF) and its net asset value (NAV) are equal at the initial issuing and maturity date, there exist discount, which is referred as spread, between the NAV and the CEF market price before the maturity date. The existence of the CEF discount is referred as a CEF discount puzzle in finance. We propose to use the embedded option to explain the spread. In particular, we use the Black-Scholes formula to evaluate the put option embedded in the CEF, and we find that the option value can explain the spread between NAV and price of CEF.  Therefore, the arbitrage opportunity may exist due to the embedded option. Furthermore, we consider some other factors such as expiration period, volatility, investment sentiment, etc. into the panel data analysis model to explain the CEF discount puzzle.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/52qsj48mhcagk3eb9vqntl4k7c","2015-04-10 11:36:37",NULL
"2999","21","COS Awards for Excellence","2015-04-16 15:00:00","2015-04-16 17:00:00","Riddick Hearth",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ha1k76fna89jklo5s1vngfddc8","2015-04-13 09:47:40",NULL
"3002","14","Departmental Tea and Cookies","2015-04-13 15:30:00","2015-04-13 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/u1371jjv99q5ooq3fi1vinenc8","2015-04-13 10:32:49",NULL
"3005","8","Generic Spectrahedral Shadows","2015-04-23 16:30:00","2015-04-23 17:30:00","SAS 4201","Rainer Sinn","http://people.math.gatech.edu/~rsinn3/","Georgia Tech",,,"Spectrahedral shadows are projections of linear sections of the cone of positive semidefinite matrices. We characterize the polynomials that vanish on the boundaries of these convex sets when both the section and the projection are generic","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ko02dr160koj0dmtmt16ebphpc","2015-04-14 15:20:43","2015-04-14 17:51:04"
"3008","28","Officer elections (and ice cream!!!)","2015-04-24 13:00:00","2015-04-24 14:00:00","Poe 244",,,,,,"We will have an end-of-year meeting replete with ice cream and officer elections! The slate is wide open, so we need a president, vice-president, treasurer, and secretary, and any student in the math department is welcome to run. 

Please feel free to ask anyone on the current leadership committee questions about these offices, and let us know if you are planning to run.","cbattis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/29tmcbre2gcco24vcchd622q9s","2015-04-14 16:58:43","2015-04-20 16:44:09"
"3011","46","Riemann Surfaces and the work of Maryam Mirzakhani, pt. 1","2015-04-20 16:00:00","2015-04-20 17:00:00","SAS 2106","Amassa Fauntleroy",,"NC State","Andrew Cooper",,"In the first talk we define a Riemann surface and discuss the cases of genus 0 and 1 in detail through examples. This will allow us to get an understanding of what is meant by moduli. The approach will be topological and analytical and follow a somewhat historical development. The talk is designed to be accessible to advanced undergraduates and graduate students.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ntvgqgoqa06b35cs3h42e9rcfs","2015-04-18 12:59:44",NULL
"3014","46","Riemann Surfaces and the work of Maryam Mirzakhani, pt. 2","2015-04-23 15:00:00","2015-04-23 16:00:00","SAS 4201","Amassa Fauntleroy",,"NC State","Andrew Cooper",,"The second talk will be a survey building on the definitions and examples of the first with the aim of explaining the Fields Medal winning work of work of Maryam Mirzakhani in topology, geometry and dynamical systems. It will also be aimed at a general (i.e. nonexpert) audience with some background in topology, geometry or dynamical systems.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/h5hm28tpoth1pq3sktaetk4b14","2015-04-18 13:00:34","2015-04-18 13:01:35"
"3017","14","Departmental Tea and Cookies","2015-04-21 15:30:00","2015-04-21 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/lor3umk1haq7k137tgs7uue6bk","2015-04-20 10:00:25",NULL
"3020","38","The Nonnegative Matrix Factorization: Methods and Applications - advised by Kazi Ito","2015-04-24 13:00:00","2015-04-24 15:00:00","SAS 3282","Amanda Landi",,,,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/r16l650gqg6ij36er072gua7mg","2015-04-20 14:11:29","2015-04-20 17:21:26"
"3023","24","Study Break and Officer Elections","2015-04-29 11:15:00","2015-04-29 12:30:00","SAS 4104",,,,,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ijm416mtmiflkjh711vv6fbj4g","2015-04-20 19:17:17",NULL
"3026","14","Undergrad Research Presentations","2015-04-22 16:30:00","2015-04-22 17:30:00",,"SAS 1218",,,,,"1.  Siddarth Agarwal

Title : Algorithmic Trading: Predicting the S&amp;P 500 with Hidden Markov Models

Abstract : This paper aims to predict the S&amp;P 500 on regular trading days using trends obtained by training a Hidden Markov Model (HMM) using commonly available market data. Daily market information is fed into this model with a window that shifts forward each day. Output probabilities are calculated by the HMM for the chance that the market is in a given state for the next day. This probability is passed on to an algorithm that interprets it to create a signal for the next day and make trades.  (Faculty mentor : Dr. Tao Pang)

2. Ryan Cinoman

Title : The Hahn-Banach Theorem and the Geometry of Normed Vector Spaces

Abstract  : Most students are familiar with the normed spaces from geometry and linear algebranamely Euclidean space, or perhaps also the taxicab or max norms. However, in functional analysis, we deal with a different type of normed space: infinite dimensional. The Hahn-Banach Theorem is an important tool with which we can show that all Banach spaces share some of the same properties that we find intuitive in finite dimensions. In my presentation, Ill explore some important results and applications that come from the Hahn-Banach theorem, such as separation of convex sets, the canonical map as well as the dual of the spaces lp, Lp and C[a,b].  (Faculty mentor : Dr. Lorena Bociu)

3.  Nicholas Dunn

Title : A Polynomial Interpretation of the Dedekind Sum

Abstract : The Dedekind sum, a peculiarly constructed sum of sawtooth functions, has many deep connections to the Dedekind eta function, and its properties have deep implications in the fields of combinatorics, number theory, and more. We introduce the inversion polynomial for Dedekind sums $f_b(x) = \sum_{(a, b) = 1}x^{inv(a,b)}$ to study the number of $s(a, b)$ which have the same value for given b. We prove several properties of this polynomial and present some conjectures. We also introduce connections between Kloosterman sums and the inversion polynomial evaluated at particular roots of unity. Finally, we improve on previously known bounds for the second highest value of the Dedekind sum and provide a conjecture for a possible generalization. Lastly, we include a new restriction on equal Dedekind sums based on the reciprocity formula.  (Faculty mentor : Dr. Sandra Paur)

4.  Darren Lipman

Title : Mathematical Apportionment and the US House of Representatives

Abstract :  This presentation will discuss mathematical apportionment, the process of proportionately distributing discrete units among a number of players in a fair and consistent manner. In particular, we will look at the apportionment process for the United States House of Representatives, various apportionment methods, and potential paradoxes that they produce. The presentation will conclude with a model of how the US House may be reapportioned based upon population changes and the addition of new states.  (Faculty mentor : Dr. Molly Fenn)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/phvl2u7fs7pk9htoblm0d1ritc","2015-04-21 15:16:27",NULL
"3029","15","Cookies and elections!","2015-04-22 15:00:00","2015-04-22 15:30:00","SAS 1102",,,,,,,"mestrait","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/753d6qi3rungok59jqug1h12rc","2015-04-22 09:56:14",NULL
"3032","14","Jim Selgrade Retirement Reception","2015-04-28 15:00:00","2015-04-28 16:00:00","SAS 4104",,,,,,"This Summer Jim Selgrade will retire after 42 years of service to NCSU and this department.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/vp1e7qqsrvqvdc3hnu2btg4rg0","2015-04-27 11:26:55",NULL
"3038","38","Modeling Follicle Wave Dynamics in the Menstrual Cycle - advised by Jim Selgrade","2015-06-11 10:00:00","2015-06-11 11:30:00","SAS 3282","Nicole Panza",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/momdh789m63liopiima7hcsudg","2015-05-11 12:11:53",NULL
"3040","38","On Demazure Crystals for the Quantum Affine Algebra Uq((sl)n) - advised by Kailash Misra","2015-06-15 14:00:00","2015-06-15 15:30:00","SAS 3282","Margaret Rahmoeller",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/fv6rls9o8hqcac43jkhjghkhd8","2015-05-15 09:06:54","2015-05-15 09:07:32"
"3041","27","27th IFIP TC7 Conference 2015 on System Modeling and Optimization","2015-06-29 08:00:00","2015-07-03 17:00:00","Sophia Antipolis, France",,,,"Lorena Bociu","http://ifip2015.inria.fr/index.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/12sbo0ahil7h06o66e9camdfa8","2015-05-27 09:49:30",NULL
"3044","9","Modeling the Dynamics of Insulin-Mediated Ovarian Steroid Production","2015-06-08 13:30:00","2015-06-08 14:30:00","SAS 4201","Erica Graham",,"NC State",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sjl22qnda24rbrdg942uhkeq6c","2015-06-03 22:44:25","2015-06-04 08:33:46"
"3047","6","Newton-Broyden method: The most recent efficient method for solving equation boundary value problems","2015-06-11 11:00:00","2015-06-11 11:00:00","SAS 4201","Ampon Dhamacharoen",,"Burapha University","Campbell",,"This presentation concentrates on solving the boundary value problems where
the differential equations are non-linear and the boundary conditions are non-linear
equations of non-separated type.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/7unfbljrhivbqao6q68chqth4o","2015-06-08 13:40:07",NULL
"3050","27","Control of Nonlinear Physical Systems:2015 American Control Conference Workshop In Celebration of the 60th Birthday of Anthony M. Bloch","2015-06-30 08:30:00","2015-06-30 18:00:00","Chicago, IL",,,,,"http://www4.ncsu.edu/~dvzenkov/conferences/acc2015.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ak1u2rqtq1svpgv5cfb4cbtegc","2015-06-12 09:50:35",NULL
"3052","8","Identifiability Problems in Statistics and Biology","2015-06-17 15:00:00","2015-06-17 16:00:00","SAS 4201","Seth Sullivant",,"NC State",,,"A parametric model is identifiable if the mapping from parameters to probability distributions (or density functions or trajectories) is one-to-one.  Since many widely used models are algebraic in nature, deciding identifiability of a model is a fundamentally algebraic problem, often of a computational nature.  This lecture series will introduce the audience to these identifiability problems and methods from computational algebra for addressing them.

Lecture 1: Introduction to Identifiability
Parametric statistical models; Definition of identifiability; Methods to test identifiability and find identifiable functions using Grobner bases; Illustration with examples from linear structural equation models or other graphical models.

Lecture 2: Phylogenetic Models
Introduction to phylogenetic models; Identifiability of tree parameters and mumerical parameters; Phylogenetic invariants; Using invariants to identify tree parameters, Kruskals theorem and application to identifiability of numerical parameters.

Lecture 3: Linear Compartment Models
ODE models, Using differential Grbner bases to compute input/output equations, Linear compartment models, Identifiability and reparametrizations of linear compartment models.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/cb3jc6jv7hem67ns4n31d1niq0","2015-06-16 09:26:05",NULL
"3054","8","Identifiability Problems in Statistics and Biology","2015-06-18 15:00:00","2015-06-18 16:00:00","SAS 4201","Seth Sullivant",,"NC State",,,"A parametric model is identifiable if the mapping from parameters to probability distributions (or density functions or trajectories) is one-to-one.  Since many widely used models are algebraic in nature, deciding identifiability of a model is a fundamentally algebraic problem, often of a computational nature.  This lecture series will introduce the audience to these identifiability problems and methods from computational algebra for addressing them.

Lecture 1: Introduction to Identifiability
Parametric statistical models; Definition of identifiability; Methods to test identifiability and find identifiable functions using Grobner bases; Illustration with examples from linear structural equation models or other graphical models.

Lecture 2: Phylogenetic Models
Introduction to phylogenetic models; Identifiability of tree parameters and mumerical parameters; Phylogenetic invariants; Using invariants to identify tree parameters, Kruskals theorem and application to identifiability of numerical parameters.

Lecture 3: Linear Compartment Models
ODE models, Using differential Grbner bases to compute input/output equations, Linear compartment models, Identifiability and reparametrizations of linear compartment models.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/63c3gul1co846gm3d31f8r2r7c","2015-06-16 09:28:12",NULL
"3055","8","Identifiability Problems in Statistics and Biology","2015-06-19 15:00:00","2015-06-19 16:00:00","SAS 4201","Seth Sullivant",,"NC State",,,"A parametric model is identifiable if the mapping from parameters to probability distributions (or density functions or trajectories) is one-to-one.  Since many widely used models are algebraic in nature, deciding identifiability of a model is a fundamentally algebraic problem, often of a computational nature.  This lecture series will introduce the audience to these identifiability problems and methods from computational algebra for addressing them.

Lecture 1: Introduction to Identifiability
Parametric statistical models; Definition of identifiability; Methods to test identifiability and find identifiable functions using Grobner bases; Illustration with examples from linear structural equation models or other graphical models.

Lecture 2: Phylogenetic Models
Introduction to phylogenetic models; Identifiability of tree parameters and mumerical parameters; Phylogenetic invariants; Using invariants to identify tree parameters, Kruskals theorem and application to identifiability of numerical parameters.

Lecture 3: Linear Compartment Models
ODE models, Using differential Grbner bases to compute input/output equations, Linear compartment models, Identifiability and reparametrizations of linear compartment models.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9h4dggcl598r0halb0m9oh0eu0","2015-06-16 09:29:06",NULL
"3056","38","Investigating Molecular Dynamics with Sparse Grid Surrogate Models - advised by Tim Kelley","2015-06-22 10:00:00","2015-06-22 11:30:00","SAS 3282","James Nance",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/btrubohsggtkkrsvaqub3so310","2015-06-17 14:41:21",NULL
"3061","1","Random walk on the Heisenberg group","2015-10-02 16:00:00","2015-10-02 17:00:00","SAS 1102","Persi Diaconis","http://statweb.stanford.edu/~cgates/PERSI/","Stanford University","Patricia Hersh",,"The Heisenberg group here is the group of 3x3 uni-upper-triangular matrices with entries mod n.  A random walk proceeds by picking a row at random and adding (or subtracting) from the row above.  I will explain why &quot;order n^2 steps are necessary and sufficient to be close to random.&quot;  The math involved touches the FFT, the uncertainty principle, Hofstadters butterfly, and other topics (along with representation theory and analysis).  I will try to explain it all &quot;in English.&quot;  This is joint work with Dan Bump, Angela Hicks, Laurent Miclo, and Harold Widom.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/6005e1hrbi5v3obeaj7ajjuvlo","2015-07-21 11:42:17","2015-07-21 16:05:23"
"3062","3","Classifying quantum symmetries","2015-10-19 15:00:00","2015-10-19 16:00:00","SAS 4201","David Penneys","http://www.math.ucla.edu/~dpenneys/","UCLA",,,"Quantum symmetries are non-commutative analogs of the representation
categories of finite groups. There is no single best axiomatization;
choices include fusion categories and standard invariants of finite
index subfactors. In one sense, subfactors of small index give the
simplest examples of quantum symmetries. I will discuss recent joint
work with Afzaly and Morrison which gives the complete classification
of subfactor standard invariants to index 5+1/4, which includes
3+\sqrt{5}, the first interesting composite index.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/r5olpr3uv2qvr9c21uf0fprfj8","2015-07-22 12:17:46","2015-09-28 20:21:15"
"3064","6","Nonequilibrium thermodynamic theories,  Onsager principles and structureproperty preserving schemes","2015-11-18 15:00:00","2015-11-18 16:00:00","SAS 4201","Qi Wang","http://people.math.sc.edu/wangq/","U of South Carolina","Zhilin Li",,"Onsagers reciprocal principle has been generalized to derived generalized hydrodynamic theories for complex fluids flows. I will discuss the generalized Onsagers principle for nonequilibrium thermodynamic systems and the dissipation associated with it. Any nonequilibrium theories, if derived using the principle, should have a positive energy production rate and thereby an energy dissipation rate. Any good numerical approximations should inherently have this property as well, a numerical scheme sharing the properties is known as the structure/property preserving scheme.  I will give a few examples where energy stable schemes are developed and used to study complex hydrodynamic phenomena. These include hydrodynamic models for multiphase complex fluids flows involving viscous fluids and liquid crystal flows.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mffg7sfctmrrgn5l69d066fs0c","2015-07-28 14:57:57","2015-11-06 13:32:03"
"3066","14","Math Department Fall Meeting","2015-08-19 16:00:00","2015-08-19 17:00:00","SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ia3hvaa1du1f2r8tba5um4dqak","2015-07-28 16:23:16",NULL
"3068","21","Loek Helminck Retirement Reception","2015-08-18 15:00:00","2015-08-18 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/l4gjakr4saellth4c4hlds6qt4","2015-07-28 16:28:01","2015-08-02 18:43:42"
"3069","14","Mathmatics Fall Departmental Reception","2015-08-19 15:30:00","2015-08-19 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/snrl63rb8dgri62bhqfaasgha8","2015-08-02 18:45:13",NULL
"3070","3","Subalgebras and reductive pairs for Lie algebras of small dimensions","2015-08-31 15:00:00","2015-08-31 16:00:00","SAS 4201","Uladimir Shtukar",,"NC Central University",,,"This research is stimulated by many issues performed in the geometry of reductive homogeneous spaces G/H. Locally it means that we need to analyze a Lie algebra g and its subalgebra h that has a reductive complement m such that g=h+m, [h,m] contained in m. Well known Lie theory guarantees that global pair (G,H) is equivalent to local pair (g,h). Authors usually suppose that the global pair and its local equivalent satisfy some special conditions which are a good base for research. One of the conditions is reductive complement m in algebra g as described above. Unfortunately, the number of examples (the real situations for g,h,m) is very short. Just symmetric homogeneous spaces are described and locally classified for simple Lie algebras. For general Lie algebras we have nothing, we dont know how many subalgebras and reductive pairs exist. This is the first reason to find subalgebras of some Lie algebras.

Some subalgebras have been found for special Lie algebras of dimensions &lt;=4 (see Journal of Mathematical Physics). Unfortunately, the corresponding classification is too big even up to inner automorphisms of Lie algebras. Evaluation details are not represented in the articles. This is the second reason to classify subalgebras of Lie algebras in some different way which is clear and well grounded. My analysis is done for two Lie algebras of dimension 3. The results will be demonstrated in the report. One Lie algebra of dimension 4 is under evaluation right now.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/96sri25o7a3ck54dki1gte1qd4","2015-08-05 17:13:26","2015-08-05 17:18:10"
"3072","4","Nonequilibrium thermodynamic theories,  Onsager principles and structureproperty preserving schemes","2015-11-18 15:00:00","2015-11-18 16:00:00","SAS 4201","Qi Wang","http://people.math.sc.edu/wangq/","University of South Carolina","Zhilin Li",,"Onsagers reciprocal principle has been generalized to derived generalized hydrodynamic theories for complex fluids flows. I will discuss the generalized Onsagers principle for nonequilibrium thermodynamic systems and the dissipation associated with it. Any nonequilibrium theories, if derived using the principle, should have a positive energy production  rate and thereby an energy dissipation rate. Any good numerical approximations should inherently have this property as well, a numerical scheme sharing the properties is known as the 
structure/property preserving scheme.  I will give a few examples where energy stable schemes are developed and used to study complex hydrodynamic phenomena. These include hydrodynamic models for multiphase complex fluids flows involving viscous fluids and liquid crystal flows.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dlqrt80g9u06uu685md81skt4c","2015-08-06 12:36:36","2015-11-04 11:35:47"
"3073","38","Parameter estimation of viscoelastic wall models in a one-dimensional circulatory network - advised by Mette Olufsen and Mansoor Haider","2015-08-18 09:00:00","2015-08-18 10:30:00","SAS 3282","Christina Battista",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/65u957gk075q7fp5u7rvpet9qc","2015-08-12 09:34:23",NULL
"3074","36",,"2015-08-28 15:00:00","2015-08-28 16:00:00","SAS 4201","Tao Pang and Seth Sullivant",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/eeavnh0iasmfa66hgo3k95392s","2015-08-14 11:00:16","2015-08-24 15:52:45"
"3076","36",,"2015-09-11 15:00:00","2015-09-11 16:00:00","SAS 4201","Kailash Misra and Ralph Smith",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/icthskso8kucem781lspsdfjfc","2015-08-14 11:02:19",NULL
"3077","36",,"2015-09-25 15:00:00","2015-09-25 16:00:00","SAS 4201","David Papp and Radmila Sazdanovic",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/13lv1tho93qpmn7b9tjg8m743k","2015-08-14 11:03:19",NULL
"3079","36",,"2015-10-16 15:00:00","2015-10-16 16:00:00","SAS 4201","Alen Alexanderian and Ricky Liu",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9ud0o4d9ik6hnga20oo0v120jo","2015-08-14 11:04:24",NULL
"3081","36",,"2015-10-30 15:00:00","2015-10-30 16:00:00","SAS 4201","Andrew Cooper and Arvind Krishna Saibaba",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qkkf5srrufkgcihs2lem41qh2o","2015-08-14 11:05:16","2015-08-17 10:47:03"
"3082","46","Set-theoretic results in mathematics","2015-09-23 16:00:00","2015-09-23 17:00:00","SAS 4201","Sakae Fuchino","http://kurt.scitec.kobe-u.ac.jp/~fuchino/index-e.html","Kobe University, Japan","Kailash Misra",,"In this talk, I will discuss some questions arose in algebra, geometry and analysis which finally found solutions in set theory.

Since the discovering of the method of forcing by Paul Cohen in 1960s,many sophisticated techniques have been developed to prove that some of the mathematical statements are independent from set theory (i.e. to _prove_ that there are no proofs or disproofs of these statements in set theory). Since the axiom system of the set theory is (believed) to include all usual mathematical arguments, questions about such statements cannot be settled in (conventional) mathematics (as far as mathematics itself is consistent).

As such examples of statements I will talk about a characterization of infinite free abelian groups (Whitehead problem, proved to be independent by S. Shelah), simplicity of the auto-homeomorphism group of  the Stone-Chech compactification of the discrete space N (the set of all natural numbers), $\beta_N$ (proved to be independent by S. Shelah and S.F.) and a generalization of Hellys theorem on
convergence of a sequence of monotone real functions (S. Plewik and S.F.). Some other more recent results will be also discussed if time permits.

The talk is thought to be for a general audience and I shall rather concentrate on the definition of the notions involved, and discussions about the meaning of the results presented and independence proof at large.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/51f2gbsgmdt2m5ph2n4alkpec8","2015-08-18 11:30:35","2015-08-20 09:23:43"
"3083","19","Interest meeting","2015-08-19 04:30:00","2015-08-19 05:30:00","SAS 2102",,,,"Graduate Student Algebra and Combinatorics Seminar",,"No talk today, but we will schedule speakers and welcome our new members.","dibernst","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/55351a8c6qs6ut0rn709ae4878","2015-08-18 16:21:16",NULL
"3084","21","8th Southeastern Lie Theory Workshop on Algebraic and Combinatorial Representation Theory","2015-10-09 08:15:00","2015-10-11 12:30:00","SAS 1102",,,,"Kailash Misra","http://www4.ncsu.edu/~misra/SELie/index3.htm",,"schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/rcn4ck804vrmleuq75klgpkk6g","2015-08-20 14:18:16","2015-09-22 11:44:15"
"3085","8","Algebraic Geometry of Gaussian Graphical Models","2015-09-01 13:30:00","2015-09-01 14:30:00","SAS 4201","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",,,"The parameter space of a Gaussian graphical model is a semialgebraic subset of the cone of positive definite matrices. This talk will describe some results on the vanishing ideals of these Gaussian graphical models.  For general graphs, it is an open problem to give generators or a Grobner basis of the vanishing ideal.  Special instances include well-studied ideals of combinatorial commutative algebra including determinantal ideals, secant ideals, and the vanishing ideals of matrix Schubert varieties.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/b9fgccuu1ugguak7ijfmc6fies","2015-08-21 13:48:00",NULL
"3087","3","Shifted symmetric functions","2015-10-12 15:00:00","2015-10-12 16:00:00","SAS 4201","Natasha Rozhkovskaya","https://www.math.ksu.edu/~rozhkovs/","Kansas State University",,,"The focus of this talk is the properties of so-called shifted Schur functions,  in particular their vertex operator presentation. Shifted Schur   functions appear in representation theory of classical Lie algebras as eigenvalues of the elements of a certain linear basis of a center of the corresponding universal enveloping algebra. The methods used to construct this linear basis can be extended further to construct  explicitly generators of  maximal commutative subalgebras in enveloping algebras, and even more, similar techniques were used recently to describe explicitly generators of Feigin-Frenkel centers of classical Lie algebras. The talk is based on a joint project with N. Jing.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/7hqeqcrhkg9u57idha80lp5itc","2015-08-24 09:02:17","2015-09-11 06:52:08"
"3089","23","Applying for Graduate Fellowships","2015-09-18 15:00:00","2015-09-18 16:00:00","SAS 4201","Seth Sullivant",,"NC State",,,"Ill discuss how to go about applying for graduate research fellowships. The focus will be on the National Science Foundation Graduate Research Fellowship but the basic principles apply to many other fellowships as well.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/b9s59j0fnr5hfn4iik2ro97fn0","2015-08-24 11:12:48",NULL
"3091","28","SpeedFriend-ing!","2015-08-31 15:00:00","2015-08-31 16:00:00","TBA",,,"NC State","AWM",,"Come join the Association for Women in Mathematics at our first event of the year! This is a great way to meet new members and get information about upcoming events and involvement with AWM. This event is open to all members of the NCSU mathematics community regardless of gender or position.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/hgaeqlf9jfhdli30veml6ghf8o","2015-08-24 15:01:39","2015-08-24 15:04:21"
"3093","14","Departmental Tea and Cookies","2015-08-26 14:30:00","2015-08-26 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/eha14b8mso570d3775k1rvfpuk","2015-08-25 11:02:46",NULL
"3094","23","Preparing your CV, Teaching &amp; Research Statements","2015-10-02 15:00:00","2015-10-02 16:00:00","SAS 4201","Faculty Panel",,"NC State","Mansoor Haider",,"This seminar is targeted at graduate students who will be on the academic job market this year or in the near future. After a short presentation on some helpful resources for your job search, well have Q&amp;A with a few faculty members on how best to prepare your application materials.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1ejqo4ro7mqim5krj6i4nsg86c","2015-08-25 13:11:13","2015-10-02 07:58:36"
"3095","19","TBA","2015-08-26 16:30:00","2015-08-26 17:30:00","SAS 2102","Daniel Bernstein",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0a0t4bhjoeq44gadfdh5b7ak8g","2015-08-25 14:49:20",NULL
"3096","19",,"2015-09-02 16:30:00","2015-09-02 17:30:00","SAS 2102","Suzanne Crifo",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/v7pv8dr47ua9kgc90tgrnj7v2s","2015-08-25 14:51:24",NULL
"3097","6","Fast algorithms for the quantum Boltzmann collision operator","2015-11-17 15:00:00","2015-11-17 15:50:00","SAS 4201","Jingwei Hu","http://www.math.purdue.edu/~hu342/","Purdue University","Alina Chertok",,"The quantum Boltzmann equation describes the non-equilibrium dynamics of a system comprised of a large number of quantum particles such as bosons or fermions. The most prominent feature of this equation is a high-dimensional integral operator modeling particle collisions, whose nonlinear and nonlocal structure poses a great challenge for numerical simulation. I will introduce two fast algorithms for the quantum Boltzmann collision operator. The first one is a quadrature based solver specifically designed for the collision operator in reduced energy space. Compared to cubic complexity of a direct evaluation, our algorithm runs in only linear complexity (optimal up to a logarithmic factor). The second one accelerates the computation of the full phase space collision operator. It is a spectral method based on a low rank expansion of the collision kernel. Numerical examples including an application to semiconductor device modeling are presented to illustrate the efficiency and accuracy of the proposed algorithms.","ipsen","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/k3glvvviu1ed29vmqq2mtaua98","2015-08-25 17:43:38","2015-10-09 09:01:17"
"3099","19",,"2015-09-09 16:30:00","2015-09-09 17:30:00","SAS 2102","McKay Sullivan",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/f1nlt6etobcqgnmonnjklb4htc","2015-08-25 20:16:33",NULL
"3100","19",,"2015-09-16 16:30:00","2015-09-16 17:30:00","SAS 2102","Mike Weselcouch",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/asqs54mftve4k487oqpaakod3s","2015-08-25 20:17:09","2015-08-25 20:18:01"
"3102","19",,"2015-09-23 16:30:00","2015-09-23 17:30:00","SAS 2102","Katie Ahrens",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9k9h693l27ub7h4tpb02fvi1eg","2015-08-25 20:19:09",NULL
"3104","19",,"2015-09-30 16:30:00","2015-09-30 17:30:00","SAS 2102","Colby Long",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2qaoglr65hlbhr21n0sq1umcgo","2015-08-25 20:19:57","2015-09-23 11:11:44"
"3105","19",,"2015-10-14 16:30:00","2015-10-14 17:30:00","SAS 2102","Molly Lynch",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4uhn4k9stuf4fhlr4rj78cfc48","2015-08-25 20:20:59",NULL
"3106","19",,"2015-11-04 16:30:00","2015-11-04 17:30:00","SAS 2102","Caprice Stanley",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qpe0tngjhs9bfah8tc056ffp30","2015-08-25 20:22:01",NULL
"3108","19",,"2015-11-11 16:30:00","2015-11-11 17:30:00","SAS 2102","Alex Chandler",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/uc663it4prabuobb29ndfspd14","2015-08-25 20:22:40",NULL
"3111","19",,"2015-10-07 16:30:00","2015-10-07 17:30:00","SAS 2102","Emily Barnard",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/cltcd1mvos3qd0m95dtbhjofjo","2015-08-25 20:26:04","2015-09-23 11:14:07"
"3113","4","Existence Theorems for a Crystal Surface Model","2015-11-11 15:00:00","2015-11-11 16:00:00","SAS 4201","Xiangsheng Xu",,"Mississippi State and Duke University","Zhilin Li","http://www.math.ncsu.edu/events/DEseminarOct2015.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/olhlvv5sp515c9ps1qh4thjp2s","2015-08-26 09:49:34","2015-10-12 09:20:39"
"3115","23","GIST Panel Discussion: Formal Classroom Assessments: Design, Implementation and Evaluation","2015-09-04 15:00:00","2015-09-04 16:00:00","SAS 4201","Faculty Panel",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sr2h4d4698j8fdfb9s8dmjteak","2015-08-26 11:17:35","2015-08-26 11:18:31"
"3117","9","Modeling gene regulatory networks that control the Arabidopsis root stem cells","2015-09-01 16:15:00","2015-09-01 17:15:00","Cox 306","Ross Sozzani","http://cals.ncsu.edu/plantbiology/Faculty/rsozzani/rsozzani.html","NC State, Dept of Plant and Microbial Biology","Alun Lloyd",,"Modeling gene regulatory networks that control the Arabidopsis root stem cells

R. Sozzani (1), M. A. de Luis Balaguer (1),  N. Clark (1,2), A. Fisher (1)
1. Department of Plant and Microbial Biology, North Carolina State University
2. Biomathematics Graduate Program, North Carolina State University 

Gaining a deeper understanding the processes of stem cell maintenance would grant us the possibility of controlling growth and development of organisms. Due to many successful efforts in genetics, molecular, and developmental and computational biology much is known about some of the players involved in stem cell regulation. However, little is known about how individual network components act together dynamically to affect stem maintenance. We have characterized the transcriptional signature of the Arabidopsis root stem cells, established causal relationships for key players of stem cell maintenance, and identified the dynamic gene regulatory networks that control stem cell regulation. We have experimentally identified the essential features of these regulatory networks and develop accurate mathematical models that describe stem cell network dynamics. Our research is aimed at revealing whether a master regulator controls the stem cell niche and its maintenance. Our approach is a step toward a predictive mechanistic model of how stem cell networks function and are regulated, which is a fundamental tool for engineering and manipulating stem cells.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ese26qh9njomu041431gre3tb8","2015-08-27 11:06:56",NULL
"3119","28","Brown Bag Lunch","2015-09-03 12:30:00","2015-09-03 13:30:00","SAS 3281",,,,,,"Please join us for our first weekly brown bag lunch of the fall semester! We will be in the 3rd Floor grad lounge from 12:30-1:30 PM - feel free to drop by at any point. You bring your lunch and well provide a tasty treat. See you there!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/77uh2pevd7ir7lsbt487sm9844","2015-08-28 11:27:37",NULL
"3120","6","A Collision-Based Hybrid Method for Linear Transport","2015-09-15 15:00:00","2015-09-15 16:00:00","SAS 4201","Cory Hauck","http://www.csm.ornl.gov/~hfd/","Oak Ridge National Lab","Pierre Gremaud",,"We present a hybrid method for simulating kinetic  
equations with multiscale phenomena in the context of linear  
transport.  The method consists of (i) partitioning the kinetic  
equation into collisional and non-collisional components; (ii)  
applying a different numerical method to each component; and (iii) re- 
partitioning the kinetic distribution after each time step in the  
algorithm.   Preliminary results show that, for a wide range of test  
problems, the combination of a low-order method for the collisional  
component and a high-order method for the non-collisional component  
provides a level of accuracy that is comparable to a uniform high- 
order treatment of the entire system.

This work is joint with Ryan McClarren, Texas A&amp;M University.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/gtpiadcfkbtedtng8q60tr6dqs","2015-08-30 19:10:55","2015-09-14 14:04:28"
"3121","6","Recent Advance on Immersed Finite Element Methods for Interface Problems","2015-10-13 15:00:00","2015-10-13 16:00:00","SAS 4201","Xu Zhang","http://www.math.purdue.edu/~xuzhang/","Purdue","Zhilin Li",,"In science and engineering, many simulations involve multiple materials. If partial differential equations are used to model these simulations, it usually leads to the so&amp;#8208;called interface problems. Classic finite elements methods can solve interface problems satisfactorily if meshes are aligned with interfaces; otherwise the convergence cannot be guaranteed. Immersed finite element (IFE) methods, on the other hand, allow interface to be immersed in elements so that their solution mesh is independent of material interface.

Classic linear/bilinear IFE methods are usually less accurate near the interface than the rest of simulation domain due to the discontinuity of IFE functions across element boundaries. In this talk, we will introduce two approaches to improve the accuracy in the vicinity of interface. The first one is to modify classic IFE methods by adding some correction terms at interface edges/faces. The second approach is to design new IFE spaces based on nonconforming finite element functions. Optimal a priori error estimates are established for both approaches. Our numerical results demonstrate the features of these new methods.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jlnasbbq1t847k6nkok5afso7s","2015-08-30 19:14:13","2015-08-31 21:11:54"
"3123","14","Departmental Tea and Cookies","2015-09-02 14:30:00","2015-09-02 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/urg7evp191agroj3htladqtaug","2015-08-31 10:26:16",NULL
"3124","22","Solving Cubics with Paper and Turtles","2015-09-03 16:00:00","2015-09-03 16:50:00","SAS 2102","Dr. Cynthia Vinzant","http://www4.ncsu.edu/~clvinzan/","NCSU",,,"What is the mathematics behind origami? What can be achieved by just folding paper? Well talk about the beautiful geometry underlying these questions and more, including a classical algorithm for solving polynomials with a turtle and more modern algorithm for solving cubic polynomials with a piece of paper.","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/g45ileqa766ljg05vool2ui480","2015-08-31 12:18:14",NULL
"3125","22","Tiling the Aztec Diamond with Dominoes","2015-09-10 16:00:00","2015-09-10 16:50:00","SAS 2102","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NCSU",,,"The study of domino tilings goes back to early 20th century physicists, who used domino tilings in a statistical-mechanical model of diatomic molecules on a surface.  A domino is a 2 X 1 rectangle.  Tiling a region in the plane by dominoes means completely covering the region with non-overlapping dominoes.  
Consider the following simple question:  How many ways can a given region of the plane be tiled by dominoes?  For example, there are two domino tilings of a 2 X 2 square.  For a general rectangular region, the formula looks strange and is difficult to prove.  For a different planar region called the Aztec diamond, the formula is quite simple.  Well discuss and illustrate a beautiful proof of the formula due to Elkies, Kuperberg, Larsen, and Propp. Time permitting, well also see what domino tilings have to do with the Arctic Circle.
The talk will be accessible to all undergraduates.  No prior knowledge of tilings will be assumed.","nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/uv1qfh345uu2onttcl94os31hk","2015-08-31 12:22:15","2015-09-08 07:47:49"
"3126","22","Flakey Math: Snowflakes, Symmetries, and Fractals","2015-11-05 16:00:00","2015-11-05 16:50:00","SAS 2102","Maggie Rahmoeller",,"Roanoke College",,,"Have you ever wondered how snowflakes are formed? Or why they appear to be so symmetrical? In this talk, well use snowflakes to discuss different symmetries of shapes and to introduce the concept of fractals.  Fractals can be described as figures that are formed from a repeating pattern at increasingly smaller scales. Specifically, well discuss the Koch snowflake and Koch curve.

This talk will be accessible to ALL undergraduates!","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/591jai97nb05m1qopqdd1nncr0","2015-08-31 12:31:05","2015-10-30 11:27:35"
"3127","21","Triangle Area Graduate Mathematics Conference","2015-10-24 09:00:00","2015-10-24 17:00:00","SAS Hall",,,,"NCSU AMS Graduate Student Chapter","https://web.math.ncsu.edu/ams/TAGMaC.html",,"schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nbeulbflurffd790tk3h535d7o","2015-08-31 14:16:41","2015-08-31 14:18:40"
"3130","8","Resultants over Commutative Idempotent Semirings I: (Algebraic aspect)","2015-11-03 13:30:00","2015-11-03 14:30:00","SAS 4201","Hoon Hong","http://www4.ncsu.edu/~hong/","NC State",,,"The resultant theory plays a crucial role in computational algebra and algebraic geometry. The theory has two aspects: algebraic and geometric. In this paper, we focus on the algebraic aspect. One of the most important and well known algebraic properties of the resultant is that it is equal to the determinant of the Sylvester matrix. In 2008, Odagiri proved that a similar property holds over the tropical semiring if one replaces subtraction with addition. The tropical semiring belongs to a large family of algebraic structures called commutative idempotent semiring. Recently, we proved that the same property (with subtraction replaced with addition) holds over an arbitrary commutative idempotent semiring.

In this talk, we will briefly go over the following:

1. The well-known resultant theory over commutative rings (Sylvester 1853).
2. An adaptation to the tropical semiring (Odagiri 2008).
3. An extension to supertropical semirings (Izhakian and Rowen 2010).
4. An extension to commutative idempotent semirings (our recent result 2015).

This is a joint work with Yonggu Kim, Georgy Scholten, J. Rafael Sendra.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/t1ogialvoml0l2s4jei43fr9n4","2015-08-31 17:39:13","2015-10-26 21:28:43"
"3132","8","Subresultants and Symmetric Interpolation","2015-11-24 13:30:00","2015-11-24 14:30:00","SAS 4201","Agnes Szanto","http://www4.ncsu.edu/~aszanto/","NC State",,,"In 1853, Sylvester introduced double sum expressions for two finite sets of indeterminates and subresultants for univariate polynomials,showing the relationship between both notions in several but not all cases. Here we show how Sylvesters double sums can be interpreted interms of symmetric multivariate Lagrange interpolation, allowing to recover in a natural way the full description of cases.We will also report on preliminary results on extensions to symmetric multivariate Hermite interpolation.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4ndbg1i0teg28aekapkcvon898","2015-09-01 11:23:59","2015-10-16 13:19:40"
"3133","8","Lower Bound for Maximum Gap of (Inverse) Cyclotomic Polynomials","2015-10-06 13:30:00","2015-10-06 14:30:00","SAS 4201","Mary Ambrosino",,"NC State",,,"Cyclotomic polynomials are fundamental in number theory and have many applications in diverse areas. When designing certain cryptosystems, it is crucial to know the sparsity structure of the cyclotomic and inverse cyclotomic polynomials, in particular, the maximum gap between two consecutive exponents that appear. In this talk, we will present several lower bounds for the maximum gaps. They are cheap to compute and are quite tight.

This is joint work with Hoon Hong and Eunjeong Lee.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hqgcor50fo9pm0g8v1etsplec8","2015-09-01 11:27:09","2015-10-02 08:53:32"
"3134","8","Algebraic methods in phase retrieval","2015-09-08 13:30:00","2015-09-08 14:30:00","SAS 4201","Cynthia Vinzant","http://www4.ncsu.edu/~clvinzan/","NC State",,,"The problem of phase retrieval is to reconstruct a signal from certain magnitude measurements. This problem is closely related to low-rank matrix completion and has many imaging-related applications. In purely mathematical terms, phase retrieval means recovering a complex vector from the modulus of its inner product with certain measurement vectors. One can ask how many measurements are necessary for this recovery to be possible. I will discuss recent progress made on this problem by translating it into algebraic language and some related open problems in symbolic computation.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qmndvs0cgqq9ppvj0o4h122uao","2015-09-01 11:34:08","2015-09-08 10:29:22"
"3136","3","Multigraded modules from fruit flies","2015-11-23 15:00:00","2015-11-23 16:00:00","SAS 4201","Ezra Miller","http://math.duke.edu/~ezra","Duke University",,,"Modules over polynomial rings can arise directly from fundamental biological problems, such as what mechanisms drive the topological variation in fruit fly wing veins.  Persistent homology uses multigraded modules to summarize the embedded planar graphs that represent wing veins.  Statistical considerations then elicit new kinds of geometric and combinatorial questions about such modules and their moduli.  Much of this talk will be spent on background, including especially an introduction to multiparameter persistent homology and its reduction to commutative algebra.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dekcnv7fff1ocker61okikplro","2015-09-01 12:10:11","2015-11-19 23:56:22"
"3137","4","A consistent hierarchy of approximations to the chemical master equation, developed for surface catalysis","2015-10-14 15:00:00","2015-10-14 16:00:00","SAS 4201","Greg Herschlag ",,"Department of Mathematics, Duke University",,,"Historically, research on catalytic surfaces has employed phenomenological kinetic equations to predict observed reaction rates and system dynamics. These models treat surfaces as a regular lattice and track the probability of finding a site in a particular state. A well mixed/maximal-entropy assumption is used to reconstruct spatially correlated information. This well-mixed assumption, however, often fails.  Generalized kinetic models and kinetic Monte Carlo methods have been developed to compensate for the loss of information, however it is the later that has risen to prominence, due to its ease of implementation along with the fact that the historical generalized kinetic models can violate a reasonable consistency criteria.  In this talk I will discuss what is meant by consistency and how the historical models violate it.  I will then develop a novel consistent hierarchy of kinetic models that are able to account for an increasing range of spatial correlations. The hierarchy is developed in the context of averaging an underlying master equation.  The talk will continue with some simple proof-of-concept examples, a realistic example in surface catalysis, and conclude with ideas on several other applications for this novel framework.  Several open mathematical questions, that have arisen as a result of this work, will also be presented.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/furlfrpmb5hhcm4l8opl8avh2c","2015-09-02 10:19:15","2015-10-01 14:24:31"
"3139","21","Faculty in Action Seminar Series","2015-09-16 17:30:00","2015-09-16 18:30:00","Riddick 301","Laura Clarke, Physics and Seth Sullivant, Mathematics",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1qp761hprb04gbtmqpg7s952h8","2015-09-04 11:15:58","2015-09-04 11:22:36"
"3143","21","Faculty in Action Seminar Series","2015-11-18 17:30:00","2015-11-18 18:30:00","Riddick 301","Walter Weare, Chemistry and Cathrine Hoyo, Biological Sciences Toxicology",,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/8scl5dfgkg0o7nbmrtf8gn53vo","2015-09-04 11:20:16","2015-09-04 11:22:55"
"3144","14","Departmental Tea and Cookies","2015-09-09 14:30:00","2015-09-09 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/d817314huheupbu775k7i9i2bs","2015-09-07 22:02:48",NULL
"3146","28","AWM Brown Bag Lunch","2015-09-10 12:30:00","2015-09-10 13:30:00","SAS 3281",,,,,,"Join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/m49fentvq9a58oer5sptcm6f0o","2015-09-07 23:03:29","2015-09-07 23:15:24"
"3148","28","AWM Brown Bag Lunch","2015-09-17 12:30:00","2015-09-17 13:30:00","SAS 3281",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/gsa3b0ip7bbvgk2t1i7eelp4qg","2015-09-07 23:14:56","2015-09-07 23:20:54"
"3149","28","AWM Brown Bag Lunch","2015-09-24 12:30:00","2015-09-24 13:30:00","SAS 3281",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/bh25s221qar5t9d2mp7qmtli08","2015-09-07 23:16:26","2015-09-07 23:21:15"
"3150","28","AWM Brown Bag Lunch","2015-10-01 12:30:00","2015-10-01 13:30:00","SAS 4104",,,,,,"Please join us in the 4th floor commons for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1ig4447f3s11i3cr9e9433bkjo","2015-09-07 23:17:32","2015-09-30 20:36:40"
"3151","28","AWM Brown Bag Lunch","2015-10-15 12:30:00","2015-10-15 13:30:00","SAS 3281",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/gjnueudelu5lg2tsfs33kjprcg","2015-09-07 23:18:33",NULL
"3153","28","AWM Brown Bag Lunch","2015-10-22 12:30:00","2015-10-22 13:30:00","SAS 4104",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6gf2b8q233iu3k0sh0n8fv3g40","2015-09-07 23:19:40","2015-10-22 11:16:46"
"3155","28","AWM Brown Bag Lunch","2015-10-29 12:30:00","2015-10-29 13:30:00","SAS 4104",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4r1bgu3hq9912i2eiq7t7vgroo","2015-09-07 23:20:34","2015-10-22 11:17:06"
"3157","28","AWM Brown Bag Lunch","2015-11-05 12:30:00","2015-11-05 13:30:00","SAS 4104",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/j72mllt9r0krh598vd1g8qaquc","2015-09-07 23:22:05","2015-10-22 11:17:36"
"3158","28","AWM Brown Bag Lunch","2015-11-12 12:30:00","2015-11-12 13:30:00","SAS 4104",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nv7v5j2bbladuac6cidtcfogn8","2015-09-07 23:22:57","2015-10-22 11:19:08"
"3160","28","AWM Brown Bag Lunch","2015-11-19 12:30:00","2015-11-19 13:30:00","SAS 4104",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4bmso3f5gkplgjqk04ipop39t4","2015-09-07 23:23:57","2015-10-22 11:19:28"
"3161","28","AWM Brown Bag Lunch","2015-12-03 12:30:00","2015-12-03 13:30:00","SAS 4104",,,,,,"Please join us for our weekly lunch! You bring your lunch, we bring a tasty treat!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/p0pdb0j0b18lkkq9sfbubg8ls0","2015-09-07 23:25:13","2015-10-22 11:21:56"
"3163","9","Personalized Medicine, a Challenge for Mathematical Modeling","2015-10-06 16:15:00","2015-10-06 17:15:00","SAS 4201","Franz Kappel","http://www.uni-graz.at/imawww/kappel/","University of Graz, Austria","Tom Banks",,"We start with a short discussion of &quot;Personalized Medicine&quot; or &quot;Precision Medicine&quot;, its justification and why it is emerging just now. The main part of the talk will be devoted to discuss the impact &quot;Personalized Medicine&quot; will have on different aspects of mathematical modelling. It is clear that treatment strategies should be based on the individual properties of the patient to be considered. In order to choose the proper medication this could be knowledge of the patients genetic profile. We shall concentrate on the situation where a mathematical model is the basis for choosing the proper therapy. In this case it is necessary to determine the key parameters of the model which capture the individual variability of the patient. This implies that we need powerful methods for all aspects of parameter identification on the basis of available data.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ft4g6o8kd6v230cmv6hs50955s","2015-09-08 05:57:29","2015-09-15 08:20:16"
"3165","3","Additional symmetries of the extended bigraded Toda hierarchy","2015-09-14 15:00:00","2015-09-14 16:00:00","SAS 4201","Bojko Bakalov","http://www4.ncsu.edu/~bnbakalo/","NC State",,,"The extended bigraded Toda hierarchy (EBTH) is an integrable system satisfied by the total descendant potential of P^1 with two orbifold points. We construct additional symmetries of the EBTH and describe explicitly their action on the Lax operator, wave operators, and tau-function of the hierarchy. In particular, we obtain infinitesimal symmetries of the EBTH that act on the tau-function as a subalgebra of the Virasoro algebra, generalizing those of Dubrovin and Zhang. This is joint work with W. Wheeless.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/lr3lcl3o0v2g6inl5u366g5t3c","2015-09-08 09:25:18",NULL
"3167","3","Twisted logarithmic modules of vertex algebras","2015-09-21 15:00:00","2015-09-21 16:00:00","SAS 4201","Bojko Bakalov","http://www4.ncsu.edu/~bnbakalo/","NC State",,,"Motivated by logarithmic conformal field theory and Gromov-Witten theory, I will introduce a notion of a twisted module of a vertex algebra relative to any (not necessarily semisimple) automorphism. Two features of such twisted modules are that they involve the logarithm of the formal variable and the action of the Virasoro operator L_0 on them is not semisimple. I will derive a Borcherds identity and commutator formula for twisted modules. Examples for affine vertex algebras, free bosons, and symplectic fermions will be presented.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jgjqg2jgik6rpi0ij762n3mtf8","2015-09-08 09:30:50","2015-09-15 07:18:16"
"3168","3","Witch Unimodular Triangulations are Your Favorite?","2015-10-30 15:00:00","2015-10-30 16:00:00","SAS 2102","Lindsay Piechnik","http://carte40.wix.com/piechnik","High Point University",,,"This Devils Eve talk highlights some of the treats of harvesting unimodular triangulations and tricks for finding them. Specific attention is given to their translation to commutative algebra, including the role of the quadratic case.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9irvdj9b6l1b7u4rj1jc4fifsc","2015-09-08 10:13:41","2015-10-20 22:46:09"
"3170","3","Mutation-linear maps","2015-09-28 15:00:00","2015-09-28 16:00:00","SAS 4201","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,,"Linear algebra can be formulated as the study of linear relations. What happens if we distinguish a subset R of the set of linear relations and reformulate linear algebra by ignoring all linear relations not in R? (For example, an independent set in this sense is a set of vectors that does not support a nontrivial linear relation contained in R.)  One might guess that the answer to the question &quot;What happens?&quot; should be &quot;Nothing interesting.&quot;  But in fact, the question is motivated by very interesting examples.  The motivating examples--the only examples I know of--come from the study of cluster algebras.  In these examples, we are studying mutation-linear algebra: studying linear relations that are preserved by matrix mutation.  In earlier work, we showed that finding a basis, in the mutation-linear sense, corresponds to finding universal coefficients for cluster algebras.

This talk will focus on the notion of mutation-linear maps.  In many cases, mutation-linear maps are closely related to coarsenings of fans, and in some cases the fans in question are the Cambrian fans (normal fans of generalized associahedra).  There is a direct connection to lattice homomorphisms between Cambrian lattices and a heuristic connection to ring homomorphisms between cluster algebras.  I will try to convey the main (mutation-linear-)algebraic, geometric, and combinatorial ideas surrounding mutation-linear maps, without assuming any prior knowledge of cluster algebras, matrix mutation, or Cambrian lattices/fans.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/beslk2f42tg39qq19lckqggaqg","2015-09-08 15:38:00","2015-09-18 17:20:25"
"3172","3","Coxeter-biCatalan Combinatorics","2015-11-09 15:00:00","2015-11-09 16:00:00","SAS 4201","Emily Barnard","http://www4.ncsu.edu/~esbarnar/","NC State Mathematics Graduate Student",,,"We pose counting problems related to the various settings for Coxeter-Catalan combinatorics (noncrossing, nonnesting, clusters, Cambrian). Each problem involves in some sense a &quot;doubling&quot; of a corresponding problem in Coxeter-Catalan combinatorics. We show that the problems all have the same answer, and we call the common solution to these problems for a given finite Coxeter group W the W-biCatalan number. This work is joint with my advisor Nathan Reading.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3980n19vvkq2djcc1spinuko6o","2015-09-08 17:54:34","2015-11-02 16:10:24"
"3174","3","Lie conformal algebras over differential rings","2015-11-16 15:00:00","2015-11-16 16:00:00","SAS 4201","Andrei Minchenko","http://www.wisdom.weizmann.ac.il/~/andreym/","Weizmann Institute, Israel",,,"The notion of a Lie conformal algebra (LCA) comes from physics, and is related to the operator product expansion. An LCA is a module over a ring of differential operators with constant coefficients, and with a bracket which may be seen as a deformation of a Lie bracket. LCA are related to linearly compact differential Lie algebras via the so-called annihilation functor. Using this observation and the Cartans classification of linearly compact simple Lie algebras, Bakalov, DAndrea and Kac classified finite simple LCA in 2000.  

I will define the notion of LCA over a ring R of differential operators with not necessarily constant coefficients, extending the known one for R=K[x]. I will explain why it is natural to study such an object and will suggest an approach for the classification of finite simple LCA over arbitrary differential fields.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1dt2m83qdelk4m8ju75eu231l8","2015-09-09 13:05:01","2015-11-10 09:37:06"
"3176","48","Trivia Night","2015-09-11 18:00:00","0000-00-00 00:00:00","SAS 2106",,,,"AMS Graduate Student Chapter",,"Join us for Trivia, pizza, and donuts!","dibernst","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1l03oloif6ms68j38c33utskq0","2015-09-09 13:10:35",NULL
"3178","46","Stable HOMFLYPT homology of torus links and categorified Young antisymmetrizers.","2015-09-16 16:00:00","2015-09-16 17:00:00","SAS 4201","Michael Abel","https://fds.duke.edu/db/aas/math/faculty/maa46","Duke","Radmila Sazdanovic",,"It can be shown that a special monomial shift on the HOMFLYPT polynomial of the (p,q)-torus link converges to a well-defined Laurent series as q goes to infinity. A similar limit in Khovanov-Rozansky HOMFLYPT homology was conjectured by Gorsky, Oblomkov, Shende, and Rasmussen and recently proven by Hogancamp. In this talk, after reviewing the relevant constructions, we will discuss a second type of limit of stable HOMFLYPT homology of (p,pk+m)-torus links, depending on m, as k goes to infinity. Along the way we introduce a categorified Young antisymmetrizer, which plays an important role in the construction. No previous knowledge of HOMFLYPT homology will be assumed. This is joint work with M. Hogancamp.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/uot4shfcnt3gmahcsn81mk8qjk","2015-09-09 16:05:30","2015-09-13 16:18:56"
"3179","46","Planar algebras in modular tensor categories","2015-10-21 16:00:00","2015-10-21 17:00:00","SAS 4201","David Penneys","http://www.math.ucla.edu/~dpenneys/","UCLA","Radmila Sazdanovic",,"Ill first give an introduction to Jones planar algebras, which are a
useful tool for the construction and classification of subfactors and
fusion categories. A folklore theorem says that sufficiently nice
planar algebras are equivalent to pivotal tensor categories together
with a distinguished choice of generating object. Ill then discuss
joint work with Henriques and Tener, which generalizes the notion of a
planar algebra in the category of vector spaces to a planar algebra
internal to a modular tensor category C. We generalize the above
theorem, showing that planar algebras internal to C are in one-to-one
correspondence with module tensor categories M for C, a functor from C
to the Drinfeld center Z(M), and a distinguished object in M which
generates M as a C-module.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/53a2kgdc5614l25k47uj13g5gc","2015-09-09 19:07:15","2015-09-28 16:44:59"
"3181","6","Modern multiscale methods for first-principles collisionless plasma simulation","2015-09-29 15:00:00","2015-09-29 15:50:00","SAS 4201","Luis Chacon",,"Los Alamos National Laboratory","Tim Kelley","http://drive.google.com/file/d/0B5o2V29F0a7keThJekpQalN4QWc/view?usp=sharing",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/m1dtqks0r8cao2n8c66bu4vlb4","2015-09-09 21:59:56","2015-09-22 13:57:47"
"3183","22","How the Talmud Divides an  Estate Among Creditors","2015-09-17 16:00:00","2015-09-17 16:50:00","SAS 2102","Stephen Schecter","http://www4.ncsu.edu/~schecter/","NC State",,"https://www.math.ncsu.edu/sumseries/fall2015/091715.pdf",,"nreadin","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/uagubbg7r6p7jlnmhgk8vkdf3k","2015-09-10 08:42:17","2015-09-14 10:31:19"
"3184","3","Proof of a conjecture of Kenyon and Wilson about semicontiguous minors","2015-11-02 14:30:00","2015-11-02 15:30:00","SAS 1218","Tri Lai","http://www.ima.umn.edu/~tmlai/","Institute for Mathematics and its Applications",,,"In their paper on circular planar electrical networks ( arXiv:1411.7425 ), Kenyon and Wilson showed how to test if an electrical network with n nodes is well-connected by checking the positivity of n(n-1)/2 minors of the response matrix. Their test was based on the fact that any contiguous minor of a matrix can be expressed as a Laurent polynomial in the central minors. Interestingly, the Laurent polynomial is the generating function of domino tilings of a weighted Aztec diamond. They also conjectured that any semicontiguous minor can be written in terms of domino tilings of a region on the square lattice. In this talk I will present a proof of the conjecture.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/25sgkrpugr9gcme7ijq4ukjk4o","2015-09-10 09:41:20","2015-10-28 08:51:24"
"3186","9","Modeling the potential for outbreaks of dengue in the Miami Urbanized Area","2015-09-29 16:15:00","2015-09-29 17:15:00","Cox 306","Michael Robert","http://www.unm.edu/~marobert/","Depts of Biology and Mathematics & Statistics, University of New Mexico","Alun Lloyd",,"Modeling the potential for outbreaks of dengue in the Miami Urbanized Area

M.A. Robert (1,2), R.C. Christofferson (3), N.J.B. Silva (1), C. Vasquez 
(4), C.N. Mores (3), H.J. Wearing (1,2)

1. Department of Biology, University of New Mexico
2. Department of Mathematics and Statistics, University of New Mexico
3. Department of Pathobiology, Louisiana State University
4. Miami-Dade County Mosquito Control Division


In recent years, hundreds of imported cases of dengue fever, vectored primarily by the mosquito species Aedes aegypti, have been reported in the Miami Urbanized Area, and small outbreaks have occurred in counties adjacent to the region. In this study, we develop a spatially explicit stochastic model parameterized with CDC light trap data from Miami-Dade County Mosquito Control and publicly available U.S. Census data. We utilize the model to determine factors that could potentially lead to successful autochthonous transmission and spread of dengue following introduction in a population representative of the Miami Urbanized Area. We show that the timing and location of introduced cases play a critical role in determining both the probability that local transmission occurs as well as the total number of cases throughout the entire region following introduction. We show that at low rates of clinical presentation, small outbreaks of dengue could go completely undetected during a season, which may confound mitigation efforts that rely upon detection.  We discuss the sensitivity of the model to several critical parameter values that are currently poorly characterized, and motivate the collection of additional data to strengthen the predictive power of this and similar models.  Finally, we emphasize the utility of the general structure of this model in studying the introduction and expansion of mosquito-borne diseases into naive populations in other regions of the United States.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0jhrbo26ralc6fsh4vi5nmnb3k","2015-09-10 10:48:20","2015-09-15 15:24:32"
"3187","8","Sparse Polynomial Interpolation Codes and their Decoding Beyond Half the Minimum Distance","2015-09-15 13:30:00","2015-09-15 14:30:00","SAS 4201","Erich Kaltofen","http://www4.ncsu.edu/~kaltofen/","NC State",,,"We present algorithms performing sparse univariate polynomial interpolation with errors in the evaluations of the polynomial. The interpolation algorithms use as a substep the Prony-Blahut algorithm, and correct errors by subsampling at an arithmetic progression of sample indices. The sparse interpolation problem with errors yields a new algebraic error-correcting code.

Over finite fields we obtain a polynomial-time list-decoder in the sense of Guruswami-Sudan for a higher than maximal error rate. Over the real numbers the maximal error rate is much larger by the Descartes rule of sign. For the latter code over the real numbers, a polynomial-time decoder for the maximal error rate is not known.

This is joint work with Clement Pernet, Univ. Grenoble.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/uguh9sge21mai397oq5qs92r68","2015-09-10 12:04:02",NULL
"3190","14","Departmental Tea and Cookies","2015-09-16 14:30:00","2015-09-16 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4dndo46hlm64la0f28dg3aa2c4","2015-09-14 09:39:52",NULL
"3191","9","A mathematical interrogation of the differential toxicity of hydroxycoumarin anticoagulants","2015-10-13 16:15:00","2015-10-13 17:15:00","Cox 306","Belinda Akpa",,"Department of Molecular Biomedical Sciences, NC State",,,"A mathematical interrogation of the differential toxicity of hydroxycoumarin anticoagulants

Agents of opportunity are readily available household or industrial chemicals that have the potential to be exploited as weapons. The compound brodifacoum is one such agent commonly used in rodenticide formulations. Derived from the anticoagulant warfarin, brodifacoum is one of a class of superwarfarins designed to overcome a growing resistance of rodents to first-generation pesticides. Designed to have high lipophilicity, the superwarfarins are assumed to exhibit increased toxicity due to their prolonged disposition in physiological tissues. However, in vivo observations suggest the additional potential for significant cytotoxicity. Brodifacoum-induced fatalities can occur before anticoagulation manifests as bleeding. Here we explore the pharmacokinetic and pharmacodynamic differences between warfarin and brodifacoum as a means of elucidating the biophysical, biochemical, and physiological mechanisms underlying the differential toxicity of these anticoagulants. A physiologically based pharmacokinetic model with target-mediated disposition of the anticoagulant compounds captures the prolonged disposition of brodifacoum in tissues. A mechanistic model of tissue partitioning for highly lipophilic compounds is modified to address saturable binding to the pharmacodynamic target enzyme, vitamin K epoxide reductase. This represents the point of integration with a fully coupled network model of the blood coagulation cascade. The biochemical cascade network permits prediction of a clinical observable, the diagnostic clotting time. A molecular level study of membrane disruption by passive permeation of these anticoagulant compounds reveals that the bolaamphiphilic character of brodifacoum gives rise to a detergent-like behavior of which the smaller molecule, warfarin is not capable.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/a6ac02dkt14jibiaackm4d769c","2015-09-15 08:21:23","2015-10-05 15:07:24"
"3192","26","PODDIEM Nonlinear model order reduction of an ADI implicit shallow water equations model","2015-09-07 16:00:00","2015-09-07 17:00:00","SAS 4201","Razvan Stefanescu",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/edl1pr2jq6q8mern0l123thlt8","2015-09-15 17:24:52",NULL
"3194","26","Mathematical Model of Hepatitis C Viral Dynamics using a Combination Therapy of Interferon, Ribavirin, and Telaprevir","2015-09-21 16:00:00","2015-09-21 17:00:00","SAS 4201","George Lankford",,"NC State",,,"Hepatitis C is a virus that affects the liver and is one of the leading causes for cirrhosis. Recently, there has been an introduction of drugs called direct acting antivirals that have improved the chance for sustained viral response from around 50% to around 90%. In this talk, we introduce a new mathematical model for Hepatitis C dynamics treated with the direct acting antiviral drug, telaprevir, alongside interferon and ribavirin. We also demonstrate the sensitivity and identifiability techniques used to validate the model, as well as fit the model to data received from clinical trials.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dqpl4dirb8945ufmh25o5qd224","2015-09-15 17:25:56","2015-09-16 10:44:27"
"3196","26","Title TBA","2015-08-28 16:00:00","2015-08-28 17:00:00","SAS 4201","Jared Catenacci",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/pbbc30odet4rfga8s2aibpg15g","2015-09-15 17:26:53",NULL
"3198","26","Analysis of Estimators for Small Sobol Indices","2015-10-05 16:00:00","2015-10-05 17:00:00","SAS 4201","Jared Cook",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/30pvii6c0itgalderleppfafdc","2015-09-15 17:27:31","2015-10-02 13:37:58"
"3199","26","Method for Calculating Surface Displacement of Soft Matter by a Static Two Dimensional Droplet","2015-10-12 16:00:00","2015-10-12 17:00:00","SAS 4201","Aaron Bardall",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/pon0ebcruh0o74s0g1qki2h1jg","2015-09-15 17:28:20","2015-10-09 13:44:11"
"3201","26","Adaptive Morris Techniques for Active Subspace Construction","2015-10-19 16:00:00","2015-10-19 17:00:00","SAS 4201","Allie Lewis",,"NC State",,,"In this presentation, we discuss the use of adaptive Morris techniques for active subspace construction. In applications ranging from neutronics models for nuclear power plant design to partial differential equations with discretized random fields, the number of inputs can range from the thousands to millions. In many cases, however, the dimension of the active subspace of influential parameters is moderate in the sense that it is less than one hundred. For codes in which adjoints are available, gradient approximations can be used to construct these active subspaces. In this presentation, we will discuss techniques which are applicable when adjoints are not available or are prohibitively expensive. Specifically, we will employ Morris indices with adaptive stepsizes and step-directions to approximate the active subspace. We illustrate these techniques using examples from nuclear and aerospace engineering.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/rtpf1sgugdqv2m2isncag4a4k0","2015-09-15 17:29:14","2015-10-13 18:06:59"
"3203","26","Parameter Subset Selection for Mixed-Effects Models","2015-10-26 16:00:00","2015-10-26 17:00:00","SAS 4201","Katie Schmidt",,"NC State",,,"Mixed-effects models are a popular choice for describing data obtained from multiple experiments, but mixed-effects model selection remains an open area of research.  Many current techniques are limited in that they are computationally prohibitive for large problems or cannot be applied to nonlinear models.  To aid in model selection, we introduce a parameter subset selection (PSS) algorithm for mixed-effects models.  We provide examples to verify the effectiveness of the PSS algorithm and to test the performance of mixed-effects model selection that makes use of parameter subset selection.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/06k80f7i4qs614uqjf6hjs24qo","2015-09-15 17:29:56","2015-10-24 10:27:07"
"3204","26","Lasso Techniques for Parameter Selection","2015-11-02 16:00:00","2015-11-02 16:00:00","SAS 4201","Kayla Coleman",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/od2tvktredt2hla3jr9tr8frpc","2015-09-15 17:30:37","2015-10-31 17:23:41"
"3206","26","Properties of a Model for Carbon Sequestration","2015-11-09 16:00:00","2015-11-09 17:00:00","SAS 4201","Elisabeth Brown",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/a52te1h9c31f23dqrglhvaf36k","2015-09-15 17:31:14","2015-11-06 11:57:08"
"3207","26","Whats the Buzz about Global Bumblebee Decline?","2015-11-16 16:00:00","2015-11-16 17:00:00","SAS 4201","Kris Tillman",,"NC State",,,"We explore the causes of global bumblebee population decline, and the devastating impacts of this trend.  We model bumblebee colonies with a system of non-linear delay differential equations and elucidate an approximation technique to solve this system.  Lastly, we discuss the challenges of model validation as well as the questions we hope to answer, as motivated by the current conservation ecology field.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qnh5d18bknfc757nuri5jopfe4","2015-09-15 17:31:55","2015-11-13 16:26:01"
"3209","26","Free Boundary Fluid-Elasticity Interactions: Existence of Optimal Control and Adjoint Sensitivity Analysis","2015-11-23 16:00:00","2015-11-23 17:00:00","SAS 4201","Kristina Martin",,"NC State",,,"We consider an optimal control problem involving a free boundary fluid-elasticity interaction described by Navier-Stokes coupled with the equations of nonlinear elastodynamics. We prove that turbulence in the fluid flow can be minimized using a distributed control and discuss the first order necessary optimality conditions. We also  provides a description of the adjoint linearized model for an analogous steady state system and optimization problem. The linearized adjoint is necessary in the derivation of optimality conditions for controls and derivative-based optimization algorithms in fluid- structure interactions.  This is work in progress in collaboration with Lorena Bociu, Lucas Castle (North Carolina State University), Daniel Toundykov (University of Nebraska, Lincoln), and Jean-Paul Zolesio (INRIA and CNRS-INLN, Sophia-Antipolis, France).","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o4lr39q7j6rfgjjavskm49ei10","2015-09-15 17:32:37","2015-11-20 22:54:47"
"3211","26","Analysis and modeling of varied sources of noise in corneal image reconstruction from OCT","2015-11-30 16:00:00","2015-11-30 17:00:00","SAS 4201","Micaela Mendlow",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/cb3tqh02lniujlaqg94u0srr7c","2015-09-15 17:32:58","2015-11-29 13:50:35"
"3215","27","Triangle Lectures in Combinatorics (TLC)","2015-10-03 09:15:00","2015-10-03 17:00:00","Physics Building, Room 128 at Duke University in Durham, NC",,,,,"https://www.math.ncsu.edu/courses/TLC/","The Triangle Lectures in Combinatorics is a series of combinatorial workshops held each semester on a Saturday in the Research Triangle region of North Carolina, funded by the National Security Agency and the National Science Foundation.  The workshop this fall will be hosted by Duke University in Durham, North Carolina on Saturday, October 3, 2015.  It will include four one hour invited talks as well as a poster session, coffee breaks, and ample time for discussions throughout the day.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/npsqf7o3964jg2kffdnk1rk3pc","2015-09-16 10:46:53","2015-09-16 10:47:37"
"3217","8","Applications of Monodromy","2015-10-20 13:30:00","2015-10-20 14:30:00","SAS 4201","Daniel Brake","http://danielthebrake.org/","University of Notre Dame",,,"Monodromy action plays an important role in a number of mathematical theories.  Stemming from a fundamental principle in complex analysis, the Cauchy integral formula, monodromy loops give all sorts of information about the interior of a region given boundary data.  The uses include computing whether a pole is contained in the interior, and determining the breakup of the sheets coming together at a pole. As a consequence, monodromy is used in numerical algebraic geometry to decompose a pure-dimensional set into its irreducible components.

This talk will give an overview of monodromy, and some new connections to algebraic geometry.  In particular, we will discuss how to use it to compute some local properties of algebraic varieties, as in the Numerical Local Irreducible Decomposition, and a new method for computing real tropical curves.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/l32cvmfjqgmmq9s7oqtplv0ns8","2015-09-16 15:41:13","2015-10-04 22:38:59"
"3218","1","The heterogeneous multiscale method","2015-11-12 16:00:00","2015-11-12 17:00:00","SAS 1102","Bjorn Engquist","https://www.ices.utexas.edu/people/107","University of Texas","Zhilin Li",,"Direct simulation of a multiscale problem is computationally challenging since the smallest scales need to be well resolved over a domain that covers the largest scales. The heterogeneous multiscale method (HMM) is a framework for coupling numerical simulations of different scales. A computational macroscale model gets microscale data from detailed simulations on smaller subsets of the full domain. We will first focus on partial differential equations and analyze HMM convergence properties for homogenization problems. Various applications, for example, to epi-taxial growth, dynamical systems and flow in porous media will be presented.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/uhe4d8cep9j425d3s48p93i7f0","2015-09-16 17:00:21","2015-10-29 13:57:07"
"3220","4","Riemann Problems for the Modified KdV-Burgers Equation","2015-09-23 15:00:00","2015-09-23 16:00:00","SAS 4201","Michael Shearer",,"NC State University",,"http://www.math.ncsu.edu/News/Shearer923.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hj8kcp8ehp9qvopd2hg5vbv6k8","2015-09-17 13:58:04",NULL
"3221","9","Reconstructing Neuronal Dynamics Using Data Assimilation","2015-09-22 16:15:00","2015-09-22 17:15:00","Cox 306","Franz Hamilton",,"NC State, Mathematics and CQSB","Alun Lloyd",,"Assimilation of data with models of physical processes is a crucial component of modern scientific analysis. In recent years, nonlinear versions of Kalman filtering have been developed, in addition to methods that estimate model parameters in parallel with the system state. However even though a model is available, it may be poor. Variables of the system may be modeled inaccurately or unmodeled altogether. In this talk I will discuss several of these issues with particular application to the reconstruction of dynamics in networks of cultured neurons.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fufdbdkmht7uvige6s1lmn7d94","2015-09-17 17:34:09","2015-09-17 23:03:17"
"3223","10","Automated Image Intelligence Adaptive Sensor Management System for High Altitude Long Endurance UAVs in a Dynamic and Anti-Access Area Denial Environment","2015-09-22 16:30:00","2015-09-22 17:30:00","Daniels 218","GiYoung Kim",,"NCSU",,,"The problem we investigate deals with an Image Intelligence (IMINT) sensor allocation schedule for High Altitude Long Endurance UAVs in a dynamic and Anti-Access Area Denial (A2AD) environment.  The objective is to maximize the Situational Awareness (SA) of decision makers.  The value of SA can be improved in two different ways.  First, if a sensor allocated to an Areas of Interest (AOI) detects target activity, then the SA value will be increased.  Second, the SA value increases if an AOI is monitored for a certain period of time, regardless of target detections.  These values are functions of the sensor allocation time, sensor type and mode.  Relatively few studies in the archival literature have been devoted to an analytic, detailed explanation of the target detection process, and AOI monitoring value dynamics.  These two values are the fundamental criteria used to choose the most judicious sensor allocation schedule.  This research presents mathematical expressions for target detection processes, and shows the monitoring value dynamics.  Furthermore, the dynamics of target detection is the result of combined processes between belligerent behavior (target activity) and friendly behavior (sensor allocation).  We investigate these combined processes and derive mathematical expressions for simplified cases.  These closed form mathematical models can be used for Measures of Effectiveness (MOEs), i.e., target activity detection to evaluate sensor allocation schedules.  We also verify these models with discrete event simulations which enable us to describe more complex systems.

We introduce several methodologies to achieve a judicious sensor allocation schedule focusing on the AOI monitoring value.  The first methodology is a discrete time integer programming model which provides an optimal solution but is impractical for real world scenarios due to its computation time.  Thus, it is necessary to trade off the quality of solution with computation time.  The Myopic Greedy Procedure (MGP) is a heuristic which chooses the largest immediate unit time return at each decision epoch.  This reduces computation time significantly, but the quality of the solution may be only 95% of optimal (for small size problems).  Another alternative is a multi-start random constructive Hybrid Myopic Greedy Procedure (H-MGP), which incorporates stochastic variation in choosing an action at each stage, and repeats it a predetermined number of times (roughly 99.3% of optimal with 1000 repetitions).  Finally, the One Stage Look Ahead (OSLA) procedure considers all the top choices at each stage for a temporary time horizon and chooses the best action (roughly 98.8% of optimal with no repetition).  Using OSLA procedure, we can have ameliorated solutions within a reasonable computation time.  Other important issues discussed in this research are methodologies for the development of input parameters for real world applications.

Refreshments will be served in 401 Daniels from 4:00 p.m.  4:30 p.m.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/igfr3nuu4fr7opgeuh9a33da1o","2015-09-18 11:20:15",NULL
"3224","46","The ribbonlength of knot diagrams","2015-10-28 16:00:00","2015-10-28 17:00:00","Sas 4201","Elizabeth Denne","http://home.wlu.edu/~dennee/","Washington & Lee University","Radmila Sazdanovic",,"The ropelength problem asks to minimize the length of a knotted space curve such that a unit tube around the curve remains embedded. A two-dimensional analog has a much more combinatorial flavor: we require a unit-width ribbon around a knot diagram to be immersed with consistent crossing information. The ribbonlength is the length of the diagram divided by the width.  In this talk I will introduce all these ideas, and show how attempting to characterize critical points for ribbonlength leads us to new results about the medial axis of an immersed disk in the plane, including a certain topological stability for thin disks.  This is joint work with John M. Sullivan and Nancy Wrinkle.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9clhpip6uc22r8cq4h0hugrgv4","2015-09-18 16:26:05","2015-10-22 11:37:35"
"3226","38","Application of Machine Learning to Sports Prediction and Medical Diagnosis - advised by Hien Tran","2015-10-21 14:30:00","2015-10-21 16:00:00","SAS 3282","Phuong Hoang",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/tqe6216opdiiv0t5t8c1caphj8","2015-09-21 08:54:39","2015-09-23 12:41:17"
"3227","14","Departmental Tea and Cookies","2015-09-23 14:30:00","2015-09-23 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/g51qmn01rn8iem90052g8c6gf4","2015-09-21 09:43:06",NULL
"3229","22","Why Knot?","2015-09-24 16:00:00","2015-09-24 16:50:00","SAS 2102","Radmila Sazdanovic","http://www4.ncsu.edu/~rsazdan/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2015/092415.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/g56k69ia3cmlo2ol67nb81csfk","2015-09-21 09:54:39",NULL
"3231","6","Weak Galerkin Finite Element Methods for PDEs","2015-11-10 15:00:00","2015-11-10 16:00:00","SAS 4201","Chunmei Wang","http://people.math.gatech.edu/~cwang462/","Georgia Tech","Zhilin Li",,"Weak Galerkin (WG) is a new finite element method for partial differential equations where the differential operators (e.g., gradient, divergence, curl, Laplacian etc) in the variational forms are approximated by weak forms as generalized distributions. The WG discretization procedure often involves the solution of inexpensive problems defined locally on each element. The solution from the local problems can be regarded as a reconstruction of the corresponding differential operators. The fundamental  difference between the weak Galerkin finite element method and other existing methods is the use of weak functions and weak derivatives (i.e., locally reconstructed differential operators) in the design of numerical schemes based on existing variational forms for the underlying PDE problems. Weak Galerkin is, therefore, a natural extension of the conforming Galerkin finite element method. Due to its great structural flexibility, the weak Galerkin finite element method is well suited to most partial differential equations by providing the needed stability and accuracy in approximation.

In this talk, the speaker will introduce a general framework for WG methods  by using the second order elliptic problem as an example.  Furthermore, the speaker will present WG finite element methods for several model PDEs, including the linear elasticity problem, a fourth order problem arising from fluorescence tomography, and the second order problem in nondivergence form. The talk should be accessible to graduate students with adequate training in computational mathematics.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3jajghjafhlm434m8aohuadrs0","2015-09-21 15:58:37","2015-09-22 11:09:45"
"3233","4","PODDEIM Reduced-Order Strategies for Efficient Four Dimensional Variational Data Assimilation","2015-09-30 15:00:00","2015-09-30 16:00:00","SAS 4201","Razvan Stefanescu",,"NC State",,,"This work studies reduced order modeling (ROM) approaches to speed up the solution of variational data assimilation problems with large scale nonlinear dynamical models. It is shown that a key ingredient for a successful reduced order solution to inverse problems is the consistency of the reduced order Karush-Kuhn-Tucker conditions with respect to the full optimality conditions. In particular, accurate reduced order approximations are needed for both the forward dynamical model and for the adjoint model. New bases selection strategies are developed for Proper Orthogonal Decomposition (POD) data assimilation using both Galerkin and Petrov-Galerkin projections.  In case of Petrov-Galerkin approach, stabilization strategies must be considered for the reduced order models. The new hybrid tensorial POD/DEIM shallow water ROM data assimilation system provides optimal solutions similar to those produced by the full resolution data assimilation system in one tenth of the computational time.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dt1761npk538tp3fid6bhgri70","2015-09-22 17:28:17",NULL
"3234","46","Algebraic Solitons for the Ricci Flow.","2015-11-04 16:00:00","2015-11-04 17:00:00","SAS 4201","Thomas Wears",,"Longwood University","Andrew Cooper and Irina Kogan",,"The Ricci flow on a smooth manifold M is a celebrated example of a geometric evolution equation that evolves the intrinsic geometry of a manifold according to its Ricci curvature. The effectiveness of the Ricci flow as a tool to address geometric and topological problems on Riemannian manifolds is well known and hardly needs to be advertised.

Recently there has been significant research towards the investigation of the Ricci flow on Lorentzian manifolds, where special attention has been paid to the so-called soliton solutions of the flow (i.e., those solutions which evolve by scaling and diffeomorphism). Additionally, soliton solutions of the Ricci flow provide a natural generalization of Einstein metrics and are natural candidates for a best metric&quot; on Lie groups and homogenous spaces and can often be found via algebraic methods alone. Such soliton structures are referred to as algebraic solitons.

In this talk, we will first provide a brief introduction/review to Lorentzian geometry and the geometry of Lie groups. We will then review the Ricci flow for both Riemannian and Lorentzian metrics on Lie groups and provide a comparison between known results in the Riemannian case and some new results in the Lorentzian case which show that the geometry of Lorentzian Ricci solitons appears to be quite rich.
An emphasis will be placed on low-dimensional examples that are aimed at providing some insight to those who are not experts in the field.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3kjnams3l4h35rl5mse3itgtr4","2015-09-22 21:50:28","2015-10-31 13:36:57"
"3236","46","Singularities of Lagrangian Mean Curvature Flow are Mild or Conical","2015-09-30 16:00:00","2015-09-30 17:00:00","SAS 4201","Andrew Cooper","http://www.math.ncsu.edu/andrew.cooper","NC State",,,"Mean curvature flow, the downward gradient flow for the area functional, preserves the Lagrangian condition if the ambient manifold is Khler-Einstein. Thomas-Yau, Joyce, and others have conjectured that mean curvature flow should find Lagrangian area-minimizers; however the development of singularities interferes with this approach. 

We will discuss recent progress in using the Maslov class of the evolving submanifold to understand the development of singularities. In particular, mild (&quot;type I&quot;) singularities occur only at certain times predicted using the Maslov class of the initial data, and all other singularities are at worst conical.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/rhigfnd8gkrbtrl5aottgajebc","2015-09-22 22:08:18",NULL
"3244","11","Careers in Financial Risk Management","2015-10-01 17:30:00","2015-10-01 18:30:00","SAS Hall 2203","Jeff R. High, Albert Hopping, Mark Jayne, and Justin Luckett","https://my.garp.org/sfdcApp?login=1/calendar_event_detail/a1U40000001dU1rEAE/chapter","Various Companies",,"https://my.garp.org/sfdcApp?login=1/calendar_event_detail/a1U40000001dU1rEAE/chapter","GARPs Raleigh NC chapter is pleased to bring together a panel of experienced professionals from risk-related fields to provide insight into the current state of the economy and trends and opportunities for careers in risk management. The panelists will provide insight for both the novice and experienced practitioners on the competency and expectation for the risk career.  

Pre-registration strongly recommended","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qsutfu8p1bllpf1gqleab28e78","2015-09-23 11:37:55","2015-09-28 13:40:34"
"3245","11","Masters of Financial Math Information Session","2015-10-15 16:00:00","2015-10-15 17:00:00","SAS 4201","Jeff Scroggs and Leslie Bowman","http://financial.math.ncsu.edu",,,,"An informal presentation about Financial Mathematics and the graduate programs available.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1siqsh18f9n830lh8oia74u4k8","2015-09-23 11:39:59","2015-09-28 13:41:16"
"3246","26","Degradation Detection in Composite Materials Using Reflectance Spectroscopy","2015-09-28 16:00:00","2015-09-28 17:00:00","SAS 4201","Jared Catenacci",,"NC State",,,"In this talk we will show that reflectance spectroscopy obtained from a thermally treated ceramic matrix composite can be used to quantity the products of oxidation. The data collection will be described in detail in order to point out the potential biasing present in the data processing. A probability distribution is imposed on select model parameters, and then non-parametrically estimated. A non-parametric estimation is chosen since the exact composition of the material is unknown due to the inherent heterogeneity of ceramic composites. We will demonstrate, using a weighted least squares estimation, that we are able to detect a distinguishable increase in the SiO2 present in the samples which were heat treated for 100 hours compared to 10 hours.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/gm12fk1qt5mj99suoc1prhafm0","2015-09-23 12:15:51",NULL
"3247","38","Supersolvable Leibniz Algebras - advised by Ernie Stitzinger","2015-10-16 09:00:00","2015-10-16 10:30:00","SAS 3282","Tiffany Burch",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/l86c1tljg9rp54cr49n8tbedd4","2015-09-23 12:40:35",NULL
"3248","15","SIAM Guest Lecturer","2015-09-29 12:30:00","2015-09-29 13:30:00","Mann 304","Luis Chacon",,"Los Alamos National Laboratory","NC State SIAM Student Chapter",,,"allewis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/7gaulo7jdn5chispemvc8kn490","2015-09-23 12:46:30","2015-09-23 12:47:13"
"3249","8","Symbolic computation and systems of PDEs","2015-10-13 13:30:00","2015-10-13 14:30:00","SAS 4201","Alexey Ovchinnikov","http://qcpages.qc.cuny.edu/~aovchinnikov/","CUNY Queens College",,,"We will discuss upper and lower bounds for the effective Nullstellensatz for systems of polynomial PDEs. These are uniform bounds for the number of differentiations to be applied to all equations of a system of PDEs in order to discover algebraically whether it is consistent (i.e., has a solution in a differential field extension). The bounds are functions of the degrees and orders of the equations of the system and the numbers of dependent and independent variables in them. Seidenberg was the first to address this problem in 1956. The first explicit bounds appeared in 2009, with the upper bound expressed in terms of the Ackermann function. In the case of one derivation, the first explicit bound is due to Grigoriev (1989). In 2014, another bound was obtained if restricted to the case of one derivation and constant coefficients. Our new result does not have these restrictions.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/56klvjiv6duocu53p9clfj42d0","2015-09-24 20:16:07","2015-10-07 06:31:09"
"3250","22","Monstrous Moonshine","2015-10-01 16:00:00","2015-10-01 16:50:00","SAS 2102","Bojko Bakalov","http://www4.ncsu.edu/~bnbakalo/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2015/100115.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/90aggfh1fs77jhst80sl5cojok","2015-09-28 10:14:48","2015-09-28 11:41:41"
"3252","14","Departmental Tea and Cookies","2015-10-02 15:30:00","2015-10-02 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/i580d9evetvvjv51k08g5ppig4","2015-09-28 13:20:27",NULL
"3254","46","Topological T-duality and Hodgkins theorem","2015-11-20 14:30:00","2015-11-20 15:30:00","SAS 2102","Pedram Hekmati ","http://www.maths.adelaide.edu.au/pedram.hekmati/","University of Adelaide, Australia","Irina Kogan",,"A famous problem in topology, first solved by Hodgkin in 1967, is to determine the K-theory of compact simply-connected Lie groups. Hodgkins original proof was extremely technical, motivating the discovery of a number of simpler proofs. In this talk I will present a new, surprisingly simple proof of Hodgkins theorem using topological T-duality, an idea that originated in physics. This is based on joint work with David Baraglia.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ld2rvjjugkha1dp9tbl98n0nrs","2015-09-29 10:43:43","2015-10-08 17:06:24"
"3256","46","Estimating Thresholding Levels for Random Fields via Euler Characteristics","2015-10-05 15:00:00","2015-10-05 16:00:00","SAS 4201","Anthea Monod","http://webee.technion.ac.il/people/monod/","Duke University","Radmila Sazdanovic",,"This talk introduces a new regression method that produces (1-\alpha) thresholds for signal detection in random fields, which bypasses knowledge of the spatial correlation structure, and relies on topological invariants of the data structure.  The idea is based on statistical estimation of Lipschitz-Killing Curvatures -- complex topological quantities that are otherwise extremely challenging to compute, both theoretically and numerically -- via generalized least squares.  These estimates then leverage powerful approximation results for Gaussian random fields to generate accurate (1-\alpha) thresholds and p-values.  This is joint work with Robert Adler (Technion), Kevin Bartz (Renaissance Technologies), and Samuel Kou (Harvard), and supported in part by the US-Israel BSF, ISF, NIH/NIGMS, and NSF.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/c9hgsh725l0e5pgv2f95j1lmpc","2015-09-29 14:44:06","2015-09-30 21:10:04"
"3257","22","One good turn deserves another","2015-10-22 16:00:00","2015-10-22 16:50:00","SAS 2102","Ricky Liu","http://www4.ncsu.edu/~riliu/","NC State",,,"Combinatorial game theory is the study of turn-based games with no elements of chance or hidden information. In this talk, we will look at some simple examples of combinatorial games and investigate their strategies. We will also discuss the arithmetic of games as developed by Berlekamp, Conway, and Guy and present the Sprague-Grundy theorem on impartial games. This talk will be accessible to all undergraduates.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o6sonk5mejnq6ppnq65b8l72c4","2015-09-29 15:42:34","2015-10-12 13:47:16"
"3258","4","Local well-posedness for quasilinear Schrodinger equations","2015-11-04 15:00:00","2015-11-04 16:00:00","SAS 4201","Jason Metcalfe",,"Department of Mathematics, UNC Chapel Hill",,,"I will speak on a recent joint study with J. Marzuola and D.
Tataru which proves low regularity local well-posedness for
quasilinear Schrodinger equations.  Similar results were previously
proved by Kenig, Ponce, and Vega in much higher regularity spaces
using an artificial viscosity method.  Our techniques, and in
particular the spaces in which we work, are motivated by those used by
Bejenaru and Tataru for semilinear equations.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/doqsniip2rbfqcdq4skg6pj260","2015-09-30 10:52:44",NULL
"3259","38","Portfolio Optimization with Stochastic Dividends and Stochastic Volatility - advised by Tao Pang","2015-11-04 10:00:00","2015-11-04 11:30:00","SAS 3282","Katherine Varga",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ai12qphce3jprimcqqqocmkuo0","2015-09-30 12:46:47","2015-09-30 12:47:28"
"3260","21","Faculty in Action Seminar Series","2015-10-14 17:30:00","2015-10-14 18:30:00","Riddick 450","Marie Davidian from Statistics Statistics and Dave Eggleston from Marine, Earth, and Atmospheric Sciences",,"NC State",,,"Sciences faculty discuss their lives and research during an informal conversation with students.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/sgdujddgbrupnn9ttgk70d6r14","2015-10-02 10:23:23","2015-10-02 10:24:46"
"3262","38","Calibration of Thermal Soil Properties in the Shallow Subsurface - advised by Tim Kelley","2015-10-27 11:00:00","2015-10-27 12:30:00","SAS 4201","Anna Fregosi",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/2rdn6po83g8u9s5g959n8pcta4","2015-10-02 11:45:56",NULL
"3265","9","The role of vector foraging behavior in pathogen transmission and control","2015-10-27 16:15:00","2015-10-27 17:15:00","Cox 306","Chris Stone",,"Department of Statistics, NC State",,,"This talk focuses on two aspects of vector foraging behavior. 1) How nectar foraging affects the transmission potential of the sub-Saharan malaria mosquito Anopheles gambiae sensu stricto. 2) How feeding by tsetse on non-human animals affects transmission and elimination strategies of sleeping sickness.

I found that malaria mosquitoes are more likely to be diverted to a nectar meal when a blood meal (a human host) is less accessible, based on experimental work in a semi-field setting where the abundance of nectariferous plants and the use of a bed net were varied. Additionally, the results show that it is mainly smaller, energetically-deprived female mosquitoes that are likely to feed on nectar. The vectorial capacity (an isolation of the entomological components of the basic reproduction number) of mosquitoes varied between settings with plant communities that differed in their ability to provide mosquitoes with nectar, but the same access to a blood host. When blood was provided at midnight, in line with An. gambiaes natural periodicity, the vectorial capacity was higher in areas with rich sugar sources. I then explored, using a matrix population model, how the evolution of behavioral resistance to bed nets is affected by both environmental conditions (nectar and human encounter rates) and control inverventions (insecticide-treated nets and attractive toxic sugar baits). This suggests behavioral resistance may be more likely to become established in areas of dense populations, and that supplementary use of ATSB shows promise as a resistance management strategy.

The second part focuses on sleeping sickness, a disease among poor, rural populations in sub-Saharan Africa. Sleeping sickness has been targeted for elimination as a public health problem, but is capable of persisting in populations at low levels of prevalence. The mechanism allowing for this persistence is poorly understood. Two mechanisms are investigated here that could allow persistence at such levels. We developed an ode model of sleeping sickness transmission allowing for heterogeneous exposure of humans to tsetse and a varying role of non-human animals, which may serve either in a zooprophylactic manner or as reservoir species. I found that supplemental use of vector control increased the probability of elimination and decreased the duration until elimination was achieved. This was more pronounced when animals did contribute to transmission, or when coverage and compliance of humans with screening operations was lower, for instance due to an inability to reach the humans at greatest risk of exposure.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2gcfug3s5cqft74duc24dgnrgg","2015-10-05 15:08:36","2015-10-20 10:32:38"
"3266","9","Adaptive management of evolutionary dynamics in arthropod pest control: accounting for uncertainty in genetic fitness in the optimal control of insecticide resistance and gene-drive deployment","2015-11-03 16:35:00","2015-11-03 17:35:00","Cox 306","Zack Brown",,"Department of Agricultural and Resource Economics, NC State",,,"Adaptive management of evolutionary dynamics in arthropod pest control: accounting for uncertainty in genetic fitness in the optimal control of insecticide resistance and gene-drive deployment

Zachary S. Brown, Hyeongyul Roh

Department of Agricultural &amp; Resource Economics
Genetic Engineering &amp; Society Center
NC State University

Abstract

Evolution of insect pests in response to selective pressure from human agricultural activities is one of the clearest examples of the economic relevance of evolutionary dynamics. Pest populations can very quickly evolve resistance to pesticides. In addition, recent advances in molecular biology have created the possibility of driving genes conferring desirable traits throughout a pest population, or even of entirely eliminating populations. Both examples involve important economic dynamics to consider: The threat of insecticide resistance creates an intertemporal tradeoff between using more pesticide to reduce pest density now at the expense of creating more resistance in the future. Deploying a gene drive may only yield significant benefits when a threshold level of genetically modified (GM) pests are released. In both cases, the economically efficient course of action is likely to depend on the genetic fitness of resistant or modified pests relative to wild-type organisms. However, fitness parameters in evolutionary models are often uncertain. Adaptive management (AM) is an approach for managing resource dynamics in the presence of such uncertainty: AM treats each decision as an opportunity to experiment with the system in situ, and allows for inference about underlying parameter values based on how the system responds. We discuss two relatively simple case-study systems where AM could potentially improve management of evolutionary dynamics: (1) refuge policy for managing pest resistance to GM Bacillus thuringiensis (Bt) crops, and (2) the release of Wolbachia-infected mosquitoes as a way to e.g. reduce mosquito-borne infections (this latter example comprising our prototype analogue to a gene drive). We illustrate the key features of the biological models necessary to apply AM tools, describe these tools and the main questions we are seeking to answer, before discussing preliminary results and next steps in our research.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0b0jk8la91jib2aj2j3qm81blc","2015-10-05 15:09:37","2015-11-02 11:05:55"
"3267","9","Translating near-infrared spectroscopy O2 saturation data for the noninvasive prediction of spatial and temporary hemodynamics during exercise","2015-11-17 16:15:00","2015-11-17 17:15:00","Cox 306","Laura Ellwein",,"Department of Mathematics and Applied Mathematics, Virginia Commonwealth University","Mette Olufsen",,"Laura Ellwein Fix
Department of Mathematics and Applied Mathematics, Virginia Commonwealth University

Translating near-infrared spectroscopy O_2 saturation data for the noninvasive prediction of spatial and temporary hemodynamics during exercise

Image-based studies conducted at rest have shown that atherosclerotic plaque in the thoracic aorta (TA) correlates with adverse wall shear stress (WSS), but there is a paucity of such data under elevated flow conditions. We developed a protocol to obtain phase contrast MRI (PC-MRI) measurements in the TA and its branches during three-tiered supine cycling, and relate these measurements with corresponding blood pressures to noninvasive tissue oxygen saturation (StO2) and oxygen extraction (CexO2) acquired during cardiopulmonary exercise testing. Subjects completed a cycling exercise protocol at rest and 130%, 150%, and 170% of resting heart rate (HR) during assessment with near-infrared spectroscopy (NIRS) and PC-MRI. Flow distributions (FD) from PC-MRI were related to regional StO2 so NIRS data can ultimately be used to set boundary conditions for computational fluid dynamics (CFD) modeling during exercise. Local quantification of WSS indices by CFD revealed progressively favorable time-averaged values with increasing exercise levels, but improvements in oscillatory shear index beyond rest were unchanged across exercise levels. Linear correlations were found between FD to the carotid branches and descending aorta vs local CexO2. A blueprint is subsequently provided for using this NIRS data in future CFD studies of the TA under simulated exercise conditions without having to conduct full-scale imaging studies during exercise.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/kbmncm3ik3bs69epattt1g58b4","2015-10-05 15:10:30","2015-11-13 11:37:42"
"3269","10","Evalueserve","2015-10-06 16:30:00","2015-10-06 17:30:00","Daniels 218","Marc Vollenweider, CEO and Amit Shanker, U.S. Head of Operations",,,,"http://www.math.ncsu.edu/OR10-6-2015.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1v4s5jhird79k5edhhm9ccoaec","2015-10-06 12:59:02",NULL
"3270","46","Geometric Aspects of Hyperbolic Conservation Laws","2015-11-11 16:00:00","2015-11-11 17:00:00","SAS 4201","Mike Benfield","http://www4.ncsu.edu/~mrbenfie/","NC State","Irina Kogan",,"I will first give a brief introduction to hyperbolic conservation laws, focusing on certain parts of the theory with an appealing geometric flavor. Then I will discuss the blowup examples which were the initial motivation behind the new results I will discuss. Finally, I will present new results on constructing systems of conservation laws with prescribed rarefaction curves.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/l8jin3frn5lst84qimpvdq2e8o","2015-10-08 17:10:33","2015-10-11 20:29:38"
"3272","14","Departmental Tea and Cookies","2015-11-12 15:30:00","2015-11-12 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/lobb90pc3q2vabgc0ga4jbnh0g","2015-10-12 09:34:19",NULL
"3274","10","The Institute for Systems Engineering Research US Army Corps of Engineers","2015-10-13 16:30:00","2015-10-13 17:30:00","Daniels 218","Corey Winton",,"NC State",,,"The US Army Corps of Engineers has recently invested heavily in expanding their logistics capabilities for military support efforts.  The Institute for Systems Engineering Research (ISER) provides support in multiple areas, including lifecycle research, risk and reliability development, resilience metric development, and a wide array of tradespace research and tool development.
 
This presentation will give a brief overview of the PLANS tool developed at the Engineer Research and Development Center (ERDC) in Vicksburg, MS.  The aim of the tool is to provide military decision makers critical information when planning logistics for troop ingress and support in a foreign theater.  
 
PLANS uses extensive remote data gathering for bathymetry, currents, wave heights, and general navigability of channels for offshore planning.  It employs discrete event simulation to model the flow of cargo through the logistics network in order to anticipate delays and gain insight into suboptimal resource distribution.  We use various network models to plan a resilient transportation network that adequately supports forward deployments from protected supply stations.  The tool is equipped to account for weather and adverse event driven delays or disruptions throughout the network.
 

Refreshments will be served in 401 Daniels from 4:00 p.m.  4:30 p.m.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fg9f69kktpii2ikl0603tfgh64","2015-10-12 09:38:10",NULL
"3275","14","Departmental Tea and Cookies","2015-10-14 14:30:00","2015-10-14 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ortmai91hvkp3lg2fnkjs195l4","2015-10-12 09:40:36",NULL
"3277","38","Algebraic and Combinatorial Properties of Statistical Models for Ranked Data - advised by Seth Sullivant","2015-12-01 15:00:00","2015-12-01 16:30:00","SAS 3282","Brandon Bock",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/79nrb2iugpn447mktc7ngim490","2015-10-12 10:51:38",NULL
"3278","34","Statistically consistent k-mer methods for phylogenetic tree reconstruction.","2015-11-05 15:00:00","2015-11-05 16:00:00","SAS 4201","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",,,"Phylogenetic construction algorithms based on k-mers counts of DNA or protein sequences are nonparametric distance methods for reconstructing phylogenetic trees from sequence data that do not depend on first constructing alignments. The methods are often used to construct the guide tree used in multiple sequence alignment. We show that when applied to data generated from a statistical model of sequence evolution, the standard k-mer methods are inconsistent, that is, even with arbitrary amounts of data, they will reconstruct the wrong tree in certain regions of parameter space. We also show how to derive model-based corrections that make the methods statistically consistent, and report on simulation studies comparing methods. This is joint work with Elizabeth Allman and John Rhodes.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6ekce4le3rk27qcpkpnsthbd1o","2015-10-14 10:17:45","2015-10-21 11:14:21"
"3280","34","Phylodynamic analysis of the emergence and epidemiological impact of transmissible defective dengue viruses.","2015-10-29 15:00:00","2015-10-29 16:00:00","SAS 4201","Ruian Ke","https://ruianke.wordpress.com/","NC State",,,"Infectious disease epidemics were traditionally analyzed by fitting dynamical models to case count data. With rapid advance of sequencing technology, viral sequencing data becomes available readily during an epidemic. However, case count data and sequencing data are often analyzed separately. A powerful approach, termed a phylodynamic approach, has been proposed recently to combine phylogenetic analyses and dynamical modeling to analyze both types of data in an integrated framework. In this talk, I will present our work using a phylodynamic approach to investigate how evolutionary and ecological processes at the intra-host and inter-host scales shaped the emergence and spread of a mysterious lineage of defective dengue virus. This approach allows us to infer the time of emergence and the route of transmission of this viral lineage, and predict its potential impact on dengue epidemiology. I will also briefly discuss open questions/challenges in analyzing intra-host and inter-host sequencing data.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mfklmp9hpmsjvo2df0fui16tb4","2015-10-14 10:20:40","2015-10-27 11:59:15"
"3282","28",,"2015-10-19 15:00:00","2015-10-19 16:00:00","SAS 2102","Emily Gordon",,"SAS",,,"Emily Gordon will be visiting AWM. Emily works at SAS and will give a short talk about her educational background, career trajectory, and time at SAS. There will be lots of time for Q&amp;A and mingling (and snacks!). Please mark the date in your calendars and plan to join us!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/slv0h4se9ch024t1smt3kt7o14","2015-10-14 13:30:08",NULL
"3283","10","Topic 1: OR in investment management practice Topic 2: A Nash equilibrium in trading that is also a competitive equilibrium","2015-10-20 16:30:00","2015-10-20 17:30:00","Daniels 218","Colm OCinneide",,"QS Investors",,,"The first part of this talk will concern quantitative investment practice and how the standard toolkit of OR, including optimization, statistics, stochastic modeling, and computer programming, is used in firms like QS Investors.
 
In the second part I will discuss research topic.  When several portfolios are to be traded simultaneously, a large trade for one client may raise transaction costs for other clients. How to treat all clients fairly?  OCinneide, Scherer and Xu (JPM, 2006) give the answer, assuming that clients have no choice but to participate in the trade.  What if clients have the option to refuse to participate?  The question of fairness then becomes a question of equilibrium in a multiplayer game.  I show that, under certain natural assumptions, the OSX (2006) approach is a Nash equilibrium of this game.  Critical to proving this result is the assumption that no client has advance knowledge of the trading needs of other clients.  The fact that all clients choose to participate in the trade is in a sense a proof that the manager has fulfilled his fiduciary duty.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0gf1ir499743qqmf2g7v54vdbo","2015-10-14 14:13:20",NULL
"3284","8","Positive Polynomials and Toric Compactifications","2015-11-12 13:30:00","2015-11-12 14:30:00","SAS 4201","Daniel Plaumann ","http://www.math.uni-konstanz.de/~plaumann/index_en.html","Universitat Konstanz",,,"The cone of positive polynomials on a non-compact subset S of R^n is notoriously difficult to describe. Certain features of this cone and computational questions are intimately related to the growth behaviour of polynomials on S. We discuss the problems that arise in examples and present new tools to adress them in a toric setup. (Joint work with Claus Scheiderer)","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ua2okcjelq0dt7neg0miqruves","2015-10-14 16:59:04","2015-10-29 12:10:09"
"3286","23","Fundamentals of Webdesign using Dreamweaver &amp; Wordpress","2015-10-23 15:00:00","2015-10-23 16:00:00","SAS 4201","Seyma Bennett-Shabbir",,"NC State",,,"Effective webpages are an important medium for disseminating information related to your background, achievements, teaching and research. For those entering the job market, they are often viewed by potential employers seeking to obtain more information about candidates. In this session, Seyma will discuss software tools and strategies for effective and easy webpage design.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/75c36lco29lrcgdba6floiqabg","2015-10-15 15:41:18","2015-10-15 15:42:07"
"3289","9","Estimating cerebral blood flow velocity in the presence of aging and hypertension","2015-10-20 16:15:00","2015-10-20 17:15:00","Cox 306","Greg Mader",,"NC State Biomathematics Graduate Student","Mette Olufsen",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9ldikh8hhe8ptb0665thdu94ro","2015-10-16 13:38:25","2015-10-19 09:34:43"
"3290","14","Departmental Tea and Cookies","2015-10-21 14:30:00","2015-10-21 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nsue16lr864o2frhfteft3cgig","2015-10-19 09:35:12","2015-10-19 09:40:42"
"3291","22","Folded ribbon knots in the plane","2015-10-29 16:00:00","2015-10-29 16:50:00","SAS 2102","Elizabeth Denne","http://home.wlu.edu/~dennee/","Washington & Lee University",,,"Imagine taking a thin rectangular strip of paper and tying a knot in it. Now press the knot flat so that the ribbon is folded, origami style. We can generalize this construction to model knots as folded ribbons lying in the plane. The ribbonlength of a knot is the the length of the knot diagram divided by the width of the ribbon around it.  In this introductory talk, well explain what a knot is, discuss the construction of folded ribbon knots, and give examples of folded ribbon knots and their ribbonlength. Well also discuss the topology of folded ribbon knots, and the problem of minimizing ribbonlength for a given knot type - it turns out there are several good candidates for this notion. This is joint work with undergraduate students from Smith College and Washington &amp; Lee University.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/p32l1oh9h90d45ehftn2irlr4s","2015-10-20 11:45:05","2015-10-22 11:38:17"
"3292","22","Non-Euclidean Geometry","2015-11-12 16:00:00","2015-11-12 16:50:00","SAS 2102","Andrei Minchenko","http://www.wisdom.weizmann.ac.il/~/andreym/","Weizmann Institute",,"https://web.math.ncsu.edu/sumseries/fall2015/111215.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/a62vssqrnpkjgbhv16f9tpu1ak","2015-10-20 11:47:29","2015-11-09 10:11:15"
"3293","22","Undergraduate Research Presentations","2015-12-03 16:00:00","2015-12-03 16:50:00","SAS 2102","Anthony Powell, Diya Sashidhar, Prem Shah, and Matthew Simpson",,,,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6jq8bu2lgl08eve3ud3nc0grfg","2015-10-20 11:49:37","2015-12-02 09:39:37"
"3294","1","Joint Math-Physics Colloquium: Strange non-chaotic golden stars","2015-12-07 16:00:00","2015-12-07 17:00:00","Riddick 301","William Ditto","https://sciences.ncsu.edu/about/staff/meet-the-dean/","Dean of the College of Sciences, NC State University",,,"The unprecedented light curves of the Kepler space telescope document how the brightness of some stars pulsates at primary and secondary frequencies whose ratios are near the golden mean, the most irrational number. A nonlinear dynamical system driven by an irrational ratio of frequencies generically exhibits a strange but non-chaotic attractor. For Keplers &quot;golden&quot; stars, we present evidence of the first observation of strange non-chaotic dynamics in nature outside the laboratory. This discovery could aid the classification and detailed modeling of variable stars.  Reference: http://dx.doi.org/10.1103/PhysRevLett.114.054101.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/1349rrde90bd65apr97qrp27kg","2015-10-21 11:15:06","2015-11-17 14:46:31"
"3295","21","Virginia Tech Math Competition at NC State","2015-10-24 09:00:00","2015-10-24 11:30:00","SAS 1220",,,,,,"Come 15 minutes earlier to fill up the registration forms. 
Bring pencil and some blank paper to work on. Past exams from VT are available &lt;a href=&quot;https://www.math.vt.edu/people/plinnell/Vtregional/exams.pdf&quot;&gt;online&lt;/a&gt;.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ldjaq22ucpnlu5laubpthhpirc","2015-10-22 10:49:57",NULL
"3297","21","Importance of STEM (Science, Technology, Education and Mathematics)","2015-11-02 15:30:00","2015-11-02 16:30:00","Park Shops 210","Tom Jones",,,,,"The College of Sciences invites you to a presentation by Astronaut Tom Jones on November 2nd starting at 3:30 in Park Shops 210.  Dr. Jones will share his experiences as an astronaut and will also discuss the importance of STEM (Science, Technology, Education and Mathematics) education.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ve3s3hn0d3s969elc4hfv39t28","2015-10-23 10:05:47",NULL
"3300","34","Phylogenetic models on species trees under the coalescent","2015-12-03 15:00:00","2015-12-03 16:00:00","SAS 4201","Julia Chifman",,"Wake Forest University and Ohio State University",,,"Organismal evolution occurs at two distinct levels; at the level of the individual genes, and at the level of the species or populations as a whole. Both levels must be considered, since the evolutionary history of the species constrains the histories for the individual genes. Each individual gene has its own phylogeny, which may not agree with the species tree. A variety of processes can cause the evolutionary history of individual genes to differ among themselves and from the overall species tree. Examples of such processes are incomplete lineage sorting (deep coalescence), hybridization, horizontal gene transfer, and gene duplication and loss. Incomplete lineage sorting (ILS) is the most serious obstacle to accurate species-trees inference from large multilocus data sets. Multispecies coalescent theory is primarily used to model ILS, and provides a model for the generation of gene trees within the containing species tree. 

This talk will provide an overview of phylogenetic models on species trees under the coalescent and some results about species tree identifiability and inference. This is joint work with Laura Kubatko, The Ohio State University.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ifg8e7qv26hiqob5a944gl9spc","2015-10-23 17:22:35","2015-10-29 14:20:33"
"3302","14","Departmental Tea and Cookies","2015-10-28 14:30:00","2015-10-28 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/dnr3vj46nvn9mng4rd60ulcmlk","2015-10-26 11:41:51",NULL
"3303","38","Biological Applications of Uncertainty Quantification, including Multiscale Daphnia Magna Population Modeling - advised by H T Banks","2015-11-13 09:15:00","2015-11-13 10:45:00","Cox 306","Kaska Adoteye",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/hoau175nh9hlh43m3eck5vfgi8","2015-10-27 16:52:41",NULL
"3304","34","Dynamic Programming for Bayesian Metagenomics: Convolution Trees, Fast Max-Convolution, and a Novel Approach to Sorting X  Y","2015-11-19 15:00:00","2015-11-19 16:00:00","SAS 4201","Oliver Serang","http://colorfulengineering.org/index.html","Freie Universitt Berlin and the Leibniz Institute of Freshwater Ecology and Inland Fisheries",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/u3n26cpeq6ocv117ciob56d240","2015-10-29 14:21:36","2015-10-30 11:51:12"
"3305","14","Departmental Tea and Cookies","2015-11-04 15:30:00","2015-11-04 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/g8ic3d354eqjnvc9ko410svd9o","2015-11-02 10:25:20","2015-11-03 13:29:05"
"3306","43","Adaptive Tracking and Parameter Identification for Nonlinear Control Systems","2015-11-04 16:15:00","2015-11-04 17:15:00","SAS 1102","Michael Malisoff ",,"LSU","campbell",,"Systems and controls is an important research area at the interface of applied mathematics and engineering. It analyzes and designs methods for influencing the behavior of dynamic systems, to achieve some predefined objective.  This involves feedback, which is the use of measurements of a systems own state to adjust the actions taken by
the system. Feedback is useful for producing robust performance in self-regulating systems and so is ubiquitous in engineering. In the first part of this talk, I will review the necessary background on control theory. Then I will discuss the adaptive tracking and parameter identification problem, which involves (a) finding a dynamic feedback that ensures that all solutions of a system track some desired reference trajectory and (b) finding a parameter estimator that converges to an unknown parameter vector that is contained in the original system. Then I will discuss my research on adaptive tracking and parameter identification under unknown control gains, including an application to marine robots.  This talk will be understandable to people who are familiar with the material in a typical basic graduate course on ordinary differential equations.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/usfncdl7varmrmbm95km9d8eqo","2015-11-02 10:46:54","2015-11-02 10:56:53"
"3307","14","Meeting with Dean Ditto","2015-11-03 16:00:00","2015-11-03 16:30:00","SAS 1102",,,,,,"There will be a tea at 3:30 pm in SAS 4104.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/675meinqadf2q7a0m3fmc79628","2015-11-03 11:27:05","2015-11-03 11:27:21"
"3308","1","Collective dynamics: consensus, the emergence  of leaders, and social hydrodynamics","2016-04-07 16:00:00","2016-04-07 17:00:00","SAS 1102","Eitan Tadmor","http://www.cscamm.umd.edu/tadmor","University of Maryland","Zhilin Li",,"Nature and human society offer many examples of self-organized behavior: ants form colonies, birds flock together, mobile networks coordinate their rendezvous, and human opinions evolve into parties. These are simple examples for collective dynamics, in which local interactions tend to self-organize into large scale clusters. We discuss the dynamics of such systems, driven by social engagement of agents with their neighbors.

We will focus on two natural questions which arise in this context. First, what is the large time behavior of such systems? The underlying issue is how different rules of engagement influence the formation of large-scale patterns, and in particular, the emergence of consensus. We propose a paradigm based on the tendency of agents to move ahead, which leads to the emergence of trails and leaders.

Second, what is the group behavior of systems that involve a large number of agents? Here one is interested in the qualitative behavior of the group rather than the dynamics of each of its agents. Agent-based models lend themselves to kinetic and hydrodynamic descriptions. It is known that smooth solutions of social hydrodynamics, if they exist, must flock. Do such smooth solutions exist? alignment-based models reflect the competition on resources which may lead to finite-time singularities. We discuss the global regularity of social hydrodynamics for sub-critical initial configurations.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/bgvskmk0t6j7ei04365jbhp330","2015-11-05 10:45:01","2016-03-21 14:05:03"
"3311","10","A View from the Trenches from an Aging Agent of Change  Some Interesting Challenges for Computational Methods","2015-11-17 16:30:00","2015-11-17 17:30:00","Daniels Hall 218","Kenneth Fordyce",,"Arkieva",,,"The 2007 paper by Tiwari and Gavirneni in Interfaces is one of many papers that discuss better synergy between theory and practice  in this case specific to inventory.  The authors observe An ability to sieve through the dense web of interrelated and uncoordinated decision making at firms would be important. The solution almost certainly does not involve applying sophisticated inventory models. The path to improvement lies with the hard work of understanding and mapping the interrelationships of all the business processes that affect inventory decisions.   We humbly suggest the solution does not involve sophisticated models not because &quot;quality detective or political work&quot; precludes it, but often the folks doing the detective work do not have the working knowledge to build and deliver sophistical models.  Agents of change can do both and this generates large benefit to the organization and identifies interesting computational challenges.  The presentation will touch on the concept of agents of change; briefly review four applications the speaker is familiar  making a point to identify the interesting computational challenges that emerge within the political story, and outline some interesting computational challenges that are floating around the general area of S&amp;OP such as, but not limited to, plan repair, time buckets, and the illusion of capacity at the central planning and factory planning level. The author has intentionally used computational instead of mathematical. He will conclude every agent of change starts with the theme song  secret agent man and evolves to got to get of here if it the last thing I ever do.
 
 
Refreshments will be served in 401 Daniels from 4:00 p.m.  4:30 p.m.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4u710kbdu47caok6t72inagtoc","2015-11-13 10:57:12",NULL
"3312","14","Departmental Tea and Cookies","2015-11-18 14:30:00","2015-11-18 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/8bhprf4tmij97v8fknplohu5ag","2015-11-16 09:34:36",NULL
"3313","21","Putnam Exam","2015-12-05 10:00:00","2015-12-05 18:00:00","SAS",,,,,,"The Putnam has 2 sections: morning session 10:00am-1:00pm and afternoon session 3:00-6:00pm. 
If you know any undergraduate student who is good in math competitions, please let him/her know about the competition.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/g7pp8cv5bkmq3722la8hv0d0qk","2015-11-17 13:34:24",NULL
"3314","46","TBA","2015-01-20 16:00:00","2015-01-20 17:00:00","SAS 4201","Gonalo Oliveira","https://fds.duke.edu/db/aas/math/gm122","Duke","Andrew Cooper",,,"aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/klrajd4kv51ur59n2ggugs8p3s","2015-11-19 11:57:47",NULL
"3315","46","Gerbes on G2 manifolds","2016-02-03 16:00:00","2016-02-03 17:00:00","SAS 4201","Goncalo Oliveira","https://fds.duke.edu/db/aas/math/gm122","Duke University","Andrew Cooper",,"On a projective complex manifold, the Abelian group of Divisors maps surjectively onto that of holomorphic line bundles (the Picard group). I shall explain a funny analogue of this for G2-manifolds using coassociative submanifolds to define an analogue of Div, and a gauge theoretical equation for a connection on a gerbe to define an analogue of Pic.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/481mm5d7abkpmgqa0c0vhvku94","2015-11-19 11:59:16","2016-01-31 13:54:55"
"3316","14","Departmental Tea and Cookies","2015-12-02 14:30:00","2015-12-02 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/mr04icij12u0a74j8u8pn655bs","2015-11-30 09:34:16","2015-11-30 09:37:11"
"3318","14","Retirement Reception for Charlene Wallace","2015-12-16 15:00:00","2015-12-16 16:00:00","SAS 4104",,,,,,"Charlene will be retiring after over 13 and half  years of service to this department and 23 years of service to NC State.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/hskqvi069u38rhmace92op9hi4","2015-11-30 09:46:59","2015-12-14 10:07:54"
"3321","14","NC State Mathematics Undergraduate Honors Presentations","2015-12-03 16:00:00","2015-12-03 17:00:00","SAS 2102","Anthony Powell, Prem Shah, Matthew Simpson and Diya Sashidhar",,,,,"1. Anthony Powell

&amp;#8203; &amp;#8203;Title: Modeling Arterial Tree Branches: A Family of Ill-Conditioned Linear Systems
 
&amp;#8203; &amp;#8203;Abstract: Continuing previous work, we examine a subset of the systemic arterial tree.  This subset admits a single inflow of blood and many outflows of blood.  It is proposed that a directed binary tree can approximate real data and model these conditions.  The nodes of the tree represent pressure between blood vessels while the edges represent the flow of blood within them.  We impose boundary conditions of an inflow and terminal pressure on the linear system.  The principal interests are the numerical results of the family of linear systems generated by the tree.  We produce this family by taking the number of generations and scaling factors as non-stationary.  We observe that widening the bounds of the scaling factors uniform distribution and increasing the size of the tree significantly increases the condition number of the linear system. We remark that several preconditioning techniques remedy the extreme condition numbers.  In addition, the relationship between solution variation and scaling factor distribution revealed geometric properties of the tree.  Further study of the geometry gave clues to identify bad cases of the linear system.  Changing the geometry by adding appendage edges to the nodes did not have a significant effect on the properties.  Imposing a minimum radius for vessels, however, highlighted the importance of choosing the scaling factor distribution.  We demonstrate that this family is a case example of sensitive systems of linear equations that can approximate real phenomena. (Faculty Mentor : Dr. Pierre Gremaud)

2.  Prem Shah

&amp;#8203; &amp;#8203;Title: Convergence of the Fourier Series; Comparison of Rate of&amp;#8203; &amp;#8203;Convergence to Haar Wavelets

&amp;#8203; &amp;#8203;Abstract: We explore a classical proof of the point-wise and uniform convergence of the trigonometric Fourier Series to particular functions.  To talk about the convergence, we introduce notions of convergent sequences and series in inner product spaces.  In particular, ideas of orthonormal sets and orthogonality arise, leading to a discussion of dense orthonormal sets and equivalent concepts.  We show that the trigonometric functions are dense in a particular set of functions.  When considering point-wise convergence, we utilize the Dirichlets Kernel and a variation of the Riemann-Lebesgue Lemma.  To show uniform convergence, we utilize the Weierstrass M-Test.  Once we prove the convergence of these functions in various spaces, we begin to analyze the effectiveness in approximating functions with the Fourier Series.  There are other dense orthonormal sets and as a specific example, we look at the Haar Wavelets.  Without going through the details of proving the totality of the Haar Wavelets, we compare the convergence rate of the Fourier series and the Haar Wavelets in a few examples. (Faculty Mentor : Dr. Robert Martin)

3.  Matthew Simpson

&amp;#8203; &amp;#8203;Title: Repetitions in the Number of Vertices of Iterated Line Graphs
 
&amp;#8203; &amp;#8203;Abstract: The line graph L(G) of a simple graph G is defined by V(L(G)) = E(G), with any two vertices in L(G) adjacent if and only if the corresponding edges in G are incident. A subject of interest is the integer sequence (|V(G)|, |V(L(G))|, |V(L(L(G)))|, ).  For a finite simple connected graph G, we look at the number of times a member of the sequence can occur in consecutive indices.  For graphs for which the sequence is convergent, a member can occur consecutively any number of times.  However, beyond these classes of graphs, numbers in the sequence can only repeat twice in a row.  Repetitions more than two in a row are impossible.(Faculty mentor: Dr. Peter Johnson, Auburn University)

&amp;#8203;4&amp;#8203;. &amp;#8203;Diya Sashidhar

 Title: Discriminating between alternative mechanisms of formation of mycobacterial granulomas in vitro
 
 Abstract: Johnes Disease is a costly chronic gastrointestinal disease which infects ruminants, such as cattle and goats, worldwide. Caused by the bacterium, Mycobacterium avium subspecies paratuberculosis, Johnes Disease triggers formation of iconic clusters of cells in the intestines called granulomas as the bodys protective mechanism. Very little is known about why these structures form and what contributes to their growth. Thus, by understanding alternative mechanisms, we can develop insight into a more effective vaccine. Using experimental data, with deterministic and stochastic simulations of two Ordinary Differential Equation Models, we explore these alternative mechanisms of this granuloma formation to further understand what factors contribute to its growth. From using mathematical modeling, it was found that the bursting and migration rate of immune cells greatly influence granuloma formation. (Faculty Mentor: Drs. Shigetoshi Eda and Vitaly Ganusov, University of Tennessee at Knoxville)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4uv2983q61j1c325p4lgmh6cio","2015-12-03 09:55:35",NULL
"3322","6","Speeding-up nonlinear inversion using randomized and optimized simultaneous sources and detectors","2015-12-15 15:00:00","2015-12-15 16:00:00","SAS 4201","Eric de Sturler",,"Virginia Tech","asaibabncsu.edu",,"In nonlinear inverse problems, the objective function often involves the solution of a discretized PDE for many right hand sides, corresponding to many measurements. Additional linear systems must be solved for evaluating or approximating the Jacobian of the nonlinear least squares problem. Hence, the solution of the inverse problem requires the solution of a very large number of large linear systems; this is the main  impediment to the effective and practical use of many imaging approaches. We propose a combination of simultaneous random sources and detectors and optimized (for the problem) sources and detectors to drastically reduce the number of systems to be solved. We apply our approach to problems in diffuse optical tomography.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/k84kkt7h1eao10ncenffnnc6ug","2015-12-13 00:37:34",NULL
"3324","2","Applied category theory and the Reeb graph interleaving distance","2016-01-13 16:00:00","2016-01-13 17:00:00","SAS 4201","Elizabeth Munch ","http://www.elizabethmunch.com","U of Albany SUNY","DDS committee",,"Topological data analysis (TDA) is a rapidly growing field which has provided many tools which are quickly becoming staples of the data analysis toolbox. In particular, TDA methods can find, summarize, and compare topological features of high dimensional and complicated data not visible to more traditional methods. In this talk, we will discuss the newly emergent branch of TDA, applied category theory. We study the Reeb graph, a commonly used topological signature for data, and its relationship with a particular type of cosheaf. This categorification allows us to define a metric on Reeb graphs, which is of the utmost necessity when studying noise and uncertainty in data. The ideas presented generalize in many directions in TDA, including providing a new understanding of the Mapper construction as well as giving a distance for a more general class of functors.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9ce7k0p4avtin5m3tdre217t4o","2015-12-22 13:32:00","2016-01-11 12:05:13"
"3325","2","Moreaus Proximity Operator: From Unilateral Mechanics to Data Science","2016-01-14 16:00:00","2016-01-14 17:00:00","SAS 4201","Patrick Combettes","https://www.ljll.math.upmc.fr/~plc/","U Pierre et Marie Curie Paris 6","DDS committee",,"The notion of best approximation from a convex set is ubiquitous in mathematical analysis. In 1962, motivated by problems in non-smooth mechanics, Jean Jacques Moreau proposed a generalization of the notion of best approximation operators for sets to that of proximity operators for functions. These operators have become central tools in the modeling and the numerical solution of a wide array of problems in data science. In this talk, an overview of proximity operators will be provided and new results on proximal splitting algorithms for big data problems will be presented. Concrete applications will be discussed, as well as open conjectures and mathematical challenges in the field.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/314qmc597cgcmvsa5nc4gc7520","2015-12-22 13:36:49","2016-01-03 20:37:10"
"3326","2","Topological modeling and analysis of complex data in biomolecules","2016-01-21 16:00:00","2016-01-21 17:00:00","SAS 4201","Kelin Xia","https://www.msu.edu/~xiakelin/","Michigan State U","DDS committee",,"Proteins are the most important biomolecules for living organisms. The understanding of protein structure, function, dynamics, and transport is one of the most challenging tasks in biological science. We have introduced persistent homology for extracting molecular topological fingerprints (MTFs) based on the persistence of molecular topological invariants. MTFs are utilized for protein characterization, identification, and classification. The multidimensional persistent homology is proposed and further used to quantitatively predict the stability of protein folding configurations generated by steered molecular dynamics. An excellent consistence between my persistent homology prediction and molecular dynamics simulation is found. Further, we introduce multiresolution persistent homology to handle complex biomolecular data. The essential idea is to match the resolution with the scale of interest so as to represent large scale datasets with appropriate resolution. By appropriately tuning the resolution of a density function, we are able to focus the topological lens on the scale of interest. The proposed multiresolution topological method has potential applications in arbitrary data sets, such as social networks, biological networks and graphs. Finally, we offer persistent homology based new strategies for topological denoising and for resolving ill-posed inverse problems.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0pmed47tshljnoj676068mkeu8","2015-12-22 13:40:10","2016-01-10 08:26:48"
"3327","2","Data analysis with dynamics on networks: Recent advances in centrality analysis, community detection and manifold learning","2016-01-28 16:30:00","2016-01-28 17:30:00","SAS 4201","Dane Taylor","https://sites.google.com/site/danetaylorresearch","UNC Chapel Hill","DDS Committee",,"The analysis of dynamics on networks is a general framework that can be used to explore patterns in empirical networks and arbitrary multivariate data. It is well known, for example, that the study of diffusion dynamics has important applications ranging from community detection and manifold learning algorithms to network centrality algorithms such as PageRank, which provides the cornerstone to Googles ranking of webpages. Diffusion and similar linear dynamics constitute an important application area for mathematical development in linear algebra, random matrix theory and spectral graph theory. At the same time, it is important to explore nonlinear and nonconservative dynamics, such as contagions, which can provide complementary insights into the organization of data. Regardless of ones choice for dynamics, a paramount research pursuit involves developing novel methodology to analyze multilayer networks, which are networks that consist of several layers that encode different types of interactions. Because layers can also encode a network at different instances in time, multilayer networks provide a powerful framework for studying time-varying data. 

In this talk, I will survey several of my recent contributions in this area: First, I will discuss the utility of random walk dynamics on multilayer networks for identifying community structures and ranking the nodes according to their importance. Specifically, I will propose a framework that extends eigenvector-based centrality measures to temporal networks and highlight interesting topics that arise in linear algebra. I will also explore fundamental limitations on community detection by developing random matrix theory for the modularity matrix, and I will use this pursuit to assess good practices for when and how to aggregate layers in a multilayer network. The second part of my talk will focus on nonlinear dynamics. I will discuss my recent work that combines mathematical techniques from two fields, computational topology and nonlinear dimension reduction, in order to study how contagions spread across networks that are spatially embedded on manifolds.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/kce74ccjafbubrgsibvltdlr2g","2015-12-22 13:42:20","2016-01-14 17:35:44"
"3328","2","Left-orderability and three-manifolds","2016-01-11 16:00:00","2016-01-11 17:00:00","SAS 4201","Tye Lidman","https://www.ma.utexas.edu/users/tlid/","Institute for Advanced Study","Agnes Szanto",,"A group is called left-orderable if it can be given a
left-invariant total order.  We will discuss the question of when the
fundamental group of a three-manifold Y is left-orderable.
Orderability is known to be related to certain topological aspects of
Y, such as the surfaces which sit inside it.  We will discuss a
conjectural relationship between left-orderability and the solutions
to a certain nonlinear PDE on Y.","aszanto","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/otu5ni5b8dh6tnhacc3pc9ipi8","2015-12-23 12:00:35","2016-01-07 10:00:35"
"3329","2","From two-dimensional topological quantum field theory to non-abelian Hodge theory","2016-01-20 16:00:00","2016-01-20 17:00:00","SAS 4201","Olivia Dumitrescu","https://sites.google.com/site/oliviamireladumitrescu","Max Planck Institute for Mathematics ",,,"We will begin with introducing a new set of axioms for a 2D TQFT based on edge-contraction operations of ribbon graphs. Surprisingly, the same edge-contraction operations, when applied to a graph enumeration problem, reproduce the Witten-Kontsevich theorem of intersection numbers. This theory then turns out to be related to the quantization of a Higgs bundle with a meromorphic Higgs field. For holomorphic Higgs bundles the quantization of Dumitrescu-Mulase leads to a construction of an oper.  Our goal of the talk is to solve Gaiotto conjecture.  Our solution to this conjecture realizes an explicit and elegant formula for the Non-Abelian Hodge correspondence on the Hitchin component, resulting in another surprising construction of a deformation family of opers.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0ofhctnf24lagpfrcpoajooatc","2015-12-23 12:04:25","2016-01-08 14:03:21"
"3330","2","A Proof of the Shuffle Conjecture","2016-01-25 15:30:00","2016-01-25 16:30:00","SAS 4201","Erik Carlsson",,"Harvard University",,,"Recently, Anton Mellit and I gave a proof of the famous shuffle conjecture of Haglund, Haiman, Loehr, Ulyanov, and Remmel, which predicts a combinatorial formula for the character of the diagonal coinvariant algebra, and other quantities coming from algebraic geometry. I will explain what this conjecture is about, its implications for representation theory, and the algebraic structures that go into this recent proof. Hopefully if there is time, I will explain some of the remarkable unsolved generalizations, and their role in algebraic geometry. This should be a very down to earth talk suitable for a general audience.","plhersh","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nmrr1ceb62lq8633kaofv2bdfg","2015-12-23 12:05:19","2016-01-24 20:44:32"
"3332","2","Calculation and Computation in differential geometry","2016-01-26 16:00:00","2016-01-26 17:00:00","SAS 4201","Vamsi Pritham Pingali","http://www.math.jhu.edu/~vpingal1/","Johns Hopkins University","Irina Kogan",,"This talk is about two different stories in complex differential geometry. One of them has to do with efficiently calculating characteristic (Chern-Weil) and secondary characteristic (Chern-Simons and Bott-Chern) forms of vector bundles. Some applications of such calculations will also be presented. The second story is about computing (approximately) the &quot;best&quot; map between two polygons taking vertices to vertices. It arises out of a real-life problem, namely, &quot;surface registration&quot;.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/diko45jr1hgjh8s8q7m60pq68o","2015-12-23 18:55:31","2016-01-08 11:23:20"
"3333","38","Structure of Cyclotomic Polynomials and Several Applications - advised by Hoon Hong","2016-03-21 11:00:00","2016-03-21 12:30:00","SAS 4201","Alaa Al-Kateeb",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/n8jsutcq2p6c3okimdjmg4hdnk","2016-01-05 14:05:28",NULL
"3334","14","Mathematics Spring Departmental Meeting","2016-01-12 16:00:00","2016-01-12 17:00:00","SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/lukp54vrk52csq8u5gh14vq28g","2016-01-06 10:46:21",NULL
"3335","14","Spring Departmental Reception","2016-01-12 15:30:00","2016-01-12 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/olmc7cvbobnpiqeqrng0fo0q9g","2016-01-06 10:48:06",NULL
"3336","3","Amalgamations and Hamilton Decompositions","2016-03-14 15:00:00","2016-03-14 16:00:00","SAS 4201","Chris Rodger","http://www.auburn.edu/~rodgec1/","Auburn University",,,"In this talk, we will explore the use of amalgamations in the construction of graph decompositions, most often looking for hamilton cycle decompositions. This method uses graph homomorphisms to envision an &quot;outline&quot; of the structure of interest, then attempts to disentangle the merging of new vertices created by the homomorphism in such an outline structure. As will be shown, this method has proved to be very effective, for example, in the studying the embedding of edge-colorings of graphs into hamilton decompositions, and the existence of latin squares with holes that satisfy some fairness properties. The talk is full of pictures with few technical details, so is suitable for a wide audience.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/earqt6fumhu33qjuiccf9sshp0","2016-01-09 19:16:53","2016-02-23 16:49:30"
"3337","14","Departmental Tea and Cookies","2016-01-11 15:30:00","2016-01-11 16:00:00","SAS 4104",,,,"Seth Sullivant",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4tabc4mtmopmk131fqjggsjfn4","2016-01-11 09:37:48","2016-01-11 09:39:16"
"3338","14","Departmental Tea and Cookies","2016-01-20 15:00:00","2016-01-20 15:30:00","SAS 4104",,,,"Seth Sullivant",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/55mjnr704ijjgpbdo2fh8spags","2016-01-11 09:38:36","2016-01-13 15:10:02"
"3339","14","Departmental Tea and Cookies","2016-01-22 15:30:00","2016-01-22 16:00:00","SAS 4104",,,,"Seth Sullivant",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ik1i1sf3u574ofri6ijevdbjm4","2016-01-11 09:40:06",NULL
"3341","14","Departmental Tea and Cookies","2016-01-26 15:30:00","2016-01-26 16:00:00","SAS 4104",,,,"Seth Sullivant",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2skgqmi9v4ek0usu38bnr38vac","2016-01-11 09:41:06",NULL
"3342","14","Departmental Tea and Cookies","2016-01-13 15:30:00","2016-01-13 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2t7teeplellt4i4imb4gedhkho","2016-01-11 12:06:41",NULL
"3343","14","Departmental Tea and Cookies","2016-01-14 15:30:00","2016-01-14 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/q51ifmobj92pmculfbbkaeio0g","2016-01-11 12:07:10",NULL
"3344","14","Departmental Tea and Cookies","2016-01-21 15:30:00","2016-01-21 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2ji3rv8m7rvcvanjh54h6bsots","2016-01-11 13:41:55",NULL
"3345","14","Departmental Tea and Cookies","2016-01-28 15:30:00","2016-01-28 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/hb5im5rkokqo2u24sbjnsaelpo","2016-01-11 13:42:27",NULL
"3346","36",,"2016-02-05 15:00:00","2016-02-05 16:00:00","SAS 4201","Bojko Bakalov and Ilse Ipsen",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0kp9qvt5g57thst4d0094rfid0","2016-01-11 16:58:30","2016-01-31 15:43:14"
"3347","36",,"2016-02-19 15:00:00","2016-02-19 16:00:00","SAS 4201","Ruian Ke and Semyon Tsynkov",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jk2asjt5r7s25bjoia10h2q77s","2016-01-11 17:04:08",NULL
"3348","36",,"2016-03-18 15:00:00","2016-03-18 16:00:00","SAS 4201","Jack Silverstein and Kevin Flores",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hh596sq5rqcb99bcv7h4agd318","2016-01-11 17:06:42","2016-03-07 16:24:18"
"3349","36",,"2016-04-01 15:00:00","2016-04-01 16:00:00","SAS 4201","Hoon Hong and Tim Kelley",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/gk92feukgtj0h5i0g2h7l3p380","2016-01-11 17:09:05","2016-03-07 16:25:26"
"3350","10","Process Flexibility for Multi-Period Production Systems","2016-01-14 16:30:00","2016-01-14 17:30:00","Daniels Hall 218","Yehua Wei",,"Fuquay School of Business, Duke University",,,"Refreshments will be served in 401 Daniels from 4:00 p.m.  4:30 p.m.

It has been well documented that a little bit of process flexibility can achieve almost all the benefit of fully flexible system in single period, newsvendor type systems. In this talk, we develop the theory of process flexibility in a multi period production systems. We propose and formalize a notion of effective chaining&quot; termed the Generalized Chaining Condition (GCC), which includes the chaining structure put forth by Jordan and Graves (1995) as a special case. Using GCC, we prove that systems with just M+N process flexibility arcs, where M and N are the number of plants and products, manufacturer can achieve almost the same performance as the fully flexible system in multi-period make-to-order systems. In addition, we propose a novel partition and join technique to find an effective structure with M+N flexibility arcs, thus providing guidelines to firms in designing their sparse flexible systems. The goal of this work is to make progress towards the better understanding of the key design principles of process flexibility structures in a multi-period environment, the study of which has been limited due to its inherent complexity.

Biography:

Yehua Wei is an Assistant Professor in the Decision Sciences area at the Fuqua School of Business. He joined Fuqua on July, 2013. Prior to that, he received his PhD in Operations Research from MIT. His research interest include designing sparse resource pooling systems, supply chain risk mitigation, and strategic customers in queueing networks. He has conducted research in both theoretical and application domains. His awards include 2nd place of the 2011 George Nicholson Paper Competition, 2nd place of the 2013 CSAMSE Best Paper Competition, and the 2014 Daniel H. Wagner Prize for Excellence in Operations Research Practice.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/35sgtj50s97hvq1n5jrekaatgo","2016-01-12 12:14:12",NULL
"3351","14","Departmental Tea and Cookies","2016-01-19 16:00:00","2016-01-19 16:30:00","SAS 4104",,,,"Applied",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/rsce6a4tu06lpvaihsvknvha0c","2016-01-12 12:36:36","2016-01-13 10:20:52"
"3352","14","Departmental Tea and Cookies","2016-02-02 15:30:00","2016-02-02 16:00:00","SAS 4104",,,,"Applied",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/25keoc5hqrql8fpr3rm29rb2i8","2016-01-12 12:37:12",NULL
"3353","28","AWM Weekly Lunches and Discussion","2016-01-20 12:30:00","2016-01-20 13:30:00","SAS 4104",,,,"Suzanne Crifo",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/i6sh84g2tgp7ip5bvkbm3flj6g","2016-01-12 15:40:00",NULL
"3354","14","Graduate Recruitment Weekend Event","2016-02-26 13:30:00","2016-02-26 17:00:00","SAS 4201",,,,"Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ac7maoia74fanhrm5ndvb0bt84","2016-01-13 09:16:10",NULL
"3355","14","Graduate Recruitment Weekend Event","2016-02-27 10:00:00","2016-02-27 16:00:00","SAS 4201",,,,"Mansoor Haider",,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4akbnqrger7h3vepcae7pnfcek","2016-01-13 09:16:59",NULL
"3357","2","Conservation laws and some applications to traffic flows","2016-01-26 14:00:00","2016-01-26 15:00:00","SAS 4201","Khai T. Nguyen","http://www.personal.psu.edu/users//k/t/ktn2/","Penn State University, Mathematics Department","Lloyd",,"In this talk, I will introduce a new class of models of traffic flow on a network of roads. In these models, the percentage of drivers who travel along an incoming road and wish to turn into an outgoing road is not a constant. Moreover, the drivers who enter a congested road are placed in a buffer of limited capacity, waiting their turn in line. The main goal is to describe traffic flow at intersections and study optimization problems on a network of roads.

I will present  the well-posedness result for a new intersection model of traffic flows, and the existence of globally optimal solutions, Nash equilibrium solutions for a decision problem involving a continuum of drivers on the network.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/757kutgns327kgngikaeakj5m4","2016-01-14 10:51:49","2016-01-26 09:25:03"
"3358","22","Hey! Thats not my hat! Derangements and the number e","2016-01-21 16:30:00","2016-01-21 17:20:00","SAS 2102","Nathan Reading",,"NC State",,"https://web.math.ncsu.edu/sumseries/spring2016/012116.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/kta34sdtfcn567fjth9srra7p0","2016-01-14 11:51:49",NULL
"3359","22","When polyhedron met polynomial","2016-02-04 16:30:00","2016-02-04 17:20:00","SAS 2102","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2016/020416.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/f2epivjkbhpl73lu71d1mfv004","2016-01-14 11:53:31","2016-02-01 11:20:28"
"3360","22","Financial Mathematics Applications and Career Paths","2016-02-11 16:30:00","2016-02-11 17:20:00","SAS 2102","Jeff Scroggs",,,,"https://web.math.ncsu.edu/sumseries/spring2016/021116.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mr5t0qtg5djpuvolisnpvq1rr8","2016-01-14 11:54:35","2016-02-02 16:25:45"
"3361","22","Can you measure the speed of sound using a beer bottle?","2016-02-18 16:30:00","2016-02-18 17:20:00","SAS 2102","Ralph Smith",,,,"https://web.math.ncsu.edu/sumseries/spring2016/021816.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/059k2ddj6kaqnenvq9nfbevgek","2016-01-14 11:55:51","2016-02-10 16:27:14"
"3362","22","Undergrad Research Presentations","2016-04-21 16:30:00","2016-04-21 17:20:00","SAS 2102","Undergraduate Researchers",,,,,"1. Alexander Hazeltine
 
Title: Biscribed Triangles on Real Quartic Plane Curves
Abstract: A non-singular complex quartic curve in the complex projective plane has exactly 28 bitangents (lines which are tangent to the curve exactly twice). In the real projective plane, this curve could have 4, 8, 16, or 28 real bitangents depending on the topology of the curve. We will consider a similar problem of counting biscribed triangles (triangles which are both circumscribed and inscribed) on non-singular quartic curves in the projective plane. It is known that there are 288 such biscribed triangles over the complex projective plane, but what what about the real projective plane? We will discuss some conjectures, examine the interactions between some real biscribed triangles and quartics, and discuss possible avenues for further research. (Faculty Mentor: Dr. Cynthia Vinzant)
 
2.  Gareth Johnson
 
Title: Resistance of vascular trees and stability to random topological changes
Abstract: The modeling of blood flow cannot be done at full scale because of the billions of blood vessels in the human body. Smaller computational domains are therefore defined, requiring the use of boundary conditions linking the modeled and un-modeled parts of the vasculature. It is known how to construct such conditions for simple fractal vascular trees. This research project is focused on the use of more realistic trees and on the effect of topological changes of these tree on their overall resistance. I will discuss the construction process and the method for computing the resistance of each tree. (Faculty Mentor: Dr. Pierre Gremaud)
 
3.  Tyler Maltba
 
Title: Optimal Stopping of Markov Chains Motivated by High-dimensional Financial Derivatives Pricing
Abstract: We study both finite-horizon and infinite-horizon optimal stopping problems that are motivated by financial derivatives.   We consider the case where the reward functions for the optimization problem vary with time.  This allows much more flexible framework when dealing with applications.  For both classes of problems, it is shown that there exist optimal stopping times that maximize expected reward.  A recursive numerical algorithm is also provided in case the optimal stopping time cannot be approached analytically. (Faculty mentor: Dr. Min Kang)","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/a3fr5h5oo65ek7cobddtnnsbv4","2016-01-14 11:56:55","2016-04-18 14:47:23"
"3363","2","Two dimensional water waves in holomorphic coordinates","2016-01-19 15:00:00","2016-01-19 16:00:00","SAS 4201","Mihaela Ifrim",,"Berkeley","bociu",,"This is joint work with Daniel Tataru, and in parts with Benjamin Harrop-Griffits and John Hunter. My talk is concerned with the infinite depth water wave equation in two space dimensions, with either gravity or surface tension. I will also make some remarks on the finite depth case, and on the infinite depth case in which constant vorticity and only gravity are assumed. We consider this problem expressed in position-velocity potential holomorphic coordinates. Viewing this problem(s) as a quasilinear dispersive equation, we develop new methods which will be used to prove enhanced lifespan of solutions and also global solutions for small and localized data. For the gravity water waves there are several results available; they have been recently obtained by Wu, Alazard-Burq-Zuily and Ionescu-Pusateri using different coordinates and methods. In the capillary water waves case, we were the first to establish a global result (two months later, Ionescu-Pusateri also announced a related result). Our goal is improve the understanding of these problems by providing a single setting for all the above cases, and presenting simpler proofs. The talk will try to be self contained.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/edf8p108qu4fgbqvm7j762kceo","2016-01-14 14:15:51","2016-01-15 21:59:53"
"3364","23","GIST Panel Discussion. Self Assessment: strategies and techniques for evaluating your teaching effectiveness","2016-02-12 15:00:00","2016-02-12 16:00:00","SAS 4201","John Griggs, Karen Keene, and Leslie Kurtz",,"NC State Mathematics and Education faculty","GIST Graduate Instructor Support  Tools","https://drive.google.com/file/d/0B7byna0AA6VmbDFpSlE4czVPMG8/view?usp=sharing",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/et89c6ia5v754nptu4f8ntqr78","2016-01-14 15:04:23","2016-02-02 16:41:52"
"3365","2","Modeling film flows in cylindrical geometries and rainfall in the tropics.","2016-01-20 14:00:00","2016-01-20 15:00:00","SAS 4201","Reed Ogrosky","http://www.math.wisc.edu/~ogrosky/","University of Wisconsin, Madison","Shearer",,"In the first part of a two-part talk, I will present a series of long-wave asymptotic models for the flow of a viscous film along the interior of a vertical tube, motivated by mucus in the human trachea.  These models capture many observed features of experiments including the growth and saturation of free-surface waves, the onset of liquid plug formation, and the topology of streamlines within the film.  The role played by the curved tube geometry in these models is a key component of their success, and makes them distinct from their popular counterpart thin-film models.  In the second part of the talk, I will present recent studies of simple deterministic and stochastic models for several tropical atmospheric phenomena  including the Walker circulation, the Madden-Julian oscillation, and convectively coupled equatorial waves  that are large contributors to variability in tropical rainfall.  These models accurately capture typical event lifetime, propagation characteristics, frequency, intermittency, and strength.  This agreement is found using a data analysis technique based on solutions to the shallow water equations frequently used in studying the tropical atmosphere, and it reveals a subtle singular limit.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2jtfetcr8j79ngl61jmr727e24","2016-01-19 09:20:42","2016-01-19 16:25:34"
"3366","2","Optimal control of free boundary problems","2016-01-22 14:00:00","2016-01-22 15:00:00","SAS 4201","Harber Antil","http://math.gmu.edu/~hantil/","George Mason University","Smith",,"Over the last decade, numerous fields have been revolutionized by surface tension driven phenomena. For instance, electrowetting provided advances in lab-on-chips; special fluids like ferrofluids have led to the design of magnetically guided drug delivery systems. To fully take advantage of these processes, one must be able to control them. However, the PDEs that govern them are nonlinear, multiscale with typically unknown domains (free boundary problems) with a Young-Laplace equation on the free boundary to account for surface tension. We will discuss the analysis and approximation of the control of a model free boundary problem with surface tension. We will conclude with a novel approach to realize the regularity of a Stokes problem with Navier slip boundary conditions which naturally appears in Stokes free boundary problem.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/b94ogft0mbkffr48usujot9ifk","2016-01-19 09:30:27","2016-01-19 16:26:12"
"3367","2","Universality in numerical computations with random data","2016-02-02 14:00:00","2016-02-02 15:00:00","SAS 4201","Thomas Trogdon",,"Courant Institute of Mathematical Sciences","campbell",,"This talk will concern recent progress on the statistical analysis of numerical algorithms with random initial data.  In particular, with appropriate randomness, the fluctuations of the iteration count (halting time) of numerous numerical algorithms have been demonstrated to be universal, i.e., independent of the distribution on the initial data. This phenomenon has given new insights into random matrix theory. Furthermore, estimates from random matrix theory allow for fluctuation limit theorems for simple algorithms and halting time estimates for others.  The universality in the halting time is directly related to the experimental work of Bakhtin and Correll on neural computation and human decision-making times.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o7ev8dntphu88btaf917tcktq4","2016-01-19 16:22:35","2016-01-20 14:42:22"
"3368","3","Total positivity for the Lagrangian Grassmannian","2016-02-19 15:00:00","2016-02-19 16:00:00","SAS 2102","Rachel Karpman","https://sites.google.com/a/umich.edu/rachel-karpman/home","University of Michigan",,,"The positroid decomposition of the Grassmannian refines the well-known Schubert decomposition, and has a rich combinatorial structure. There are a number of interesting combinatorial posets which index positroid varieties, just as Young diagrams index Schubert varieties.  In addition, Postnikovs boundary measurement map gives a family of parametrizations for each positroid variety.  The domain of each parametrization is the space of edge weights of a weighted planar network.  The positroid stratification of the Grassmannian provides an elementary example of Lusztigs theory of total nonnegativity for partial flag varieties, and has remarkable applications to particle physics. In this talk, we generalize the combinatorics of positroid varieties to the Lagrangian Grassmannian, the moduli space of maximal isotropic subspaces with respect to a symplectic form.  All relevant background information on the positroid decomposition will be included in the talk.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/rugcb0hgntrl7444kjuadni5mk","2016-01-20 11:11:04","2016-02-02 17:23:24"
"3369","3","An Overview of Lecture Hall Partitions","2016-04-11 15:00:00","2016-04-11 16:00:00","SAS 4201","Carla Savage","http://www4.ncsu.edu/~savage/","NC State",,,"Lecture hall partitions were introduced by Bousquet Melou and Eriksson in 1997.  They gained attention because of their strikingly simple generating function and their connection to Eulers partition theorem. In the time since, lecture hall partitions and their generalizations have been shown to be  interesting structures with applications in combinatorics and number theory. Surprising connections have surfaced with, for example, generalizations of Eulers partition theorem, overpartitions, Goellnitzs little partition theorems, permutation statistics, Eulerian polynomials, Ehrhart theory, inversion sequences, the real-rootedness of descent polynomials of finite Coxeter groups, multiset permutations, Gorenstein cones and self-reciprocal polynomials, the restricted Eulerian polynomials of Chung and Graham, integer partitions with even indexed parts even, and pattern avoidance in permutations. We give an overview of these connections and mention some recent results.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hr7pcs9ac2i43l2dsnhd5kmndc","2016-01-20 12:19:59","2016-03-27 18:09:18"
"3370","22","Leveraging the Power of Heat to Find Optimal Shapes","2016-01-28 16:30:00","2016-01-28 17:30:00","SAS 2102","Andrew Cooper","http://www4.ncsu.edu/~aacoope2/","NC State",,,"In physical media, heat flows out of hot spots and into cold spots. In fact, it does so very quickly, until it is distributed as evenly as possible given the circumstances.

In this talk, well learn how to treat geometric objects (polygons, curves, and surfaces) as though they were temperature distributions, and let heat work its magic to produce evenly distributed--that is, symmetric--versions. 

Well talk about the ramifications of this idea in pure mathematics, where it is has helped to answer the question Which shapes are possible?. The heat approach to geometry also has applications in computer graphics and imaging, and in physics, where it may shed light on the question What is the shape of the universe?","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0177fttpsk3oik7as3gltso790","2016-01-20 15:27:00",NULL
"3371","26","Higher-Order PDE Describing Two-Phase Flow in a Hele-Shaw Cell","2016-01-25 16:00:00","2016-01-25 17:00:00","SAS 1102","Melissa Strait",,"NC State",,,"A phase field model for two-fluid flow, developed by Cueto-Felgueroso and Juanes, results in a singular PDE with higher-order terms. We find traveling wave solutions of the PDE for different constitutive laws, describing flow in a capillary tube and in a Hele-Shaw cell. The behavior near the singularity is analyzed. Finite difference simulations of the injection of gas into water show a traveling wave advancing ahead of a diffusive wave. Linear stability analysis shows the interfaces of plane wave solutions are unstable when a less viscous fluid displaces a more viscous fluid, leading to fingering behavior at the front. The interface is stable when the intruding fluid is more viscous.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/agkp09gmqoiofqej3ju1rcg0qc","2016-01-21 14:57:51","2016-01-25 10:51:35"
"3372","46","The four-genus of connected sums of torus knots","2016-02-24 16:00:00","2016-02-24 17:00:00","SAS 4201","Cornelia Van Cott ","https://www.usfca.edu/faculty/cornelia-van-cott","University of San Francisco","Radmila Sazdanovic",,"We consider the problem of finding surfaces of minimal genus in B^4 with boundary equal to the connected sum of torus knots. This problem arises naturally in the study of deformations of algebraic curves and in determining the minimal cobordism distance between torus knots. We will show that the classical Tristram-Levine signature function as well as the recently defined Upsilon function both provide some elegant answers to this problem. This is joint work with Chuck Livingston.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fqfnpispn3uh0djcmbt7u4rlu8","2016-01-23 22:48:06","2016-02-20 19:59:12"
"3374","2","Optimal control of free boundary problems","2016-01-25 14:00:00","2016-01-25 15:00:00","SAS 4201","Harbir Antil",,"George Mason University","Ralph Smith",,"Over the last decade, numerous fields have been revolutionized by surface tension driven phenomena. For instance, electrowetting provided advances in lab-on-chips; special fluids like ferrofluids have led to the design of magnetically guided drug delivery systems. To fully take advantage of these processes, one must be able to control them. However, the PDEs that govern them are nonlinear, multiscale with typically unknown domains (free boundary problems) with a Young-Laplace equation on the free boundary to account for surface tension. We will discuss the analysis and approximation of the control of a model free boundary problem with surface tension. We will conclude with a novel approach to realize the regularity of a Stokes problem with Navier slip boundary conditions which naturally appears in Stokes free boundary problem.","rsmith","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6vuodc1gr9am2q5skpdlu7n5q8","2016-01-25 09:08:30",NULL
"3375","14","Departmental Tea and Cookies","2016-01-25 15:00:00","2016-01-25 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4ros5cp1q2rrf47vfk7rpg9juk","2016-01-25 10:35:41",NULL
"3376","2","From Sparsity in Images and Information Science to Efficient PDE Solvers","2016-01-28 15:00:00","2016-01-28 16:00:00","SAS 4201","Dominique Zosso","http://www.math.ucla.edu/~zosso/",,,,"There is a strong convergence between problems and methods in imaging, data science and machine learning. Maybe more unexpectedly, elliptic PDEs equally bear strong similarities with these imaging and data problems. In this talk, I will present recent and ongoing research on numerical schemes associated with optimization problems in imaging/data science, and naturally related to elliptic PDEs. Recently, the primal-dual hybrid gradients (PDHG) method has been revived. In our work, we realize that in the particular yet frequent case of Dirichlet-energy problems, the proximal update of the dual problem has an immediate, simple solution, and the dual variable can be eliminated altogether. The resulting scheme is reduced to a primal update problem that contains a momentum term, which significantly boosts the convergence over standard gradient descent. Since elliptic PDEs describe the minimizers of associated convex minimization problems, this algorithm extends to the explicit, fast solution of elliptic PDE problems without operator inversion. I will describe our algorithm in detail on a simple Laplace problem and briefly analyze the dynamics of the resulting optimization scheme. We then look at more interesting PDE and optimization problems, ranging from classical image denoising, motion by mean curvature, the obstacle problem, to nonconvex problems such as  Eigenfunctions of the Schrdinger operator and pagerank on graphs. The proposed algorithms are derived in a disciplined way, are simple to interpret and implement, and generally competitively fast.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o1j3m1c2qjc83aokn0u6s0md44","2016-01-25 11:24:05","2016-01-25 16:13:20"
"3377","46","A New Approach to Moving Frames and their Applications","2016-04-04 16:00:00","2016-04-04 17:00:00","SAS 1102","Peter Olver","http://www.math.umn.edu/~olver/","University of Minnesota","Irina Kogan",,"The classical method of moving frames was developed by Elie Cartan into a powerful tool for studying the geometry of submanifolds under certain geometrical transformation groups. In this talk, I will present a new foundation for moving frame theory based on equivariant maps. The method is completely algorithmic, and applies to very general Lie group actions and even infinite-dimensional pseudo-groups.  The talk will survey the key ideas, and present some of the principal new applications, concentrating on image processing, the calculus of variations, geometric flows, and invariant numerical algorithms.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/k0d9a7dbsgn0rsek9bcpo6qupc","2016-01-26 10:34:10","2016-03-30 11:58:51"
"3378","26","Linearized Hydro-Elasticity: A Numerical Study","2016-02-29 16:00:00","2016-02-29 17:00:00","SAS 4201","Steven Derochers",,"NC State",,,"In view of control and stability theory, a new linearization around a steady state of a fluid-structure interaction model is considered. The linearization is performed with respect to an external forcing term and was obtained in [Bociu-Zolesio, 2013], using shape optimization techniques, which are most suited to incorporating the geometry of the problem into the analysis. This refined description brings up new termsmissing in the classical coupling of linear Stokes flow and linear elasticityin the matching of the normal stresses and velocities on the interface. It was recently shown in [Bociu-Toundykov-Zolesio,2015] that this linear PDE system generates a C_0 semigroup, but, unlike in standard Stokes-elasticity coupling, the well-posedness result is highly dependent on the fluids viscosity and the new boundary terms which, among other things, involve the curvature of the interface. In this talk, we discuss the implementation of a finite element scheme for approximating solutions of this fluid-elasticity dynamics and the numerical investigation of the dependence of the discretized model on the new terms present therein, in contrast with the classical Stokes-linear elasticity system.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/na5cgompg1vouivun99u3rgvl8","2016-01-26 16:44:45","2016-02-28 12:31:04"
"3380","26","Lasso Techniques for Parameter Estimation","2016-03-28 16:00:00","2016-03-28 16:30:00","SAS 4201","Kayla Coleman",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4frln4bm7cac2cdmht2vdv0820","2016-01-26 16:46:18","2016-03-27 12:29:33"
"3381","26","Building a Surrogate Model for Simulation of Interacting Particles","2016-04-25 16:00:00","2016-04-25 16:30:00","SAS 4201","Tricity Andrew",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9ovagehkudjjgfveh42t7gmkro","2016-01-26 16:47:02","2016-04-20 14:57:27"
"3382","26","Dynamical Mode Decomposition on a Beam Model","2016-04-11 16:00:00","2016-04-11 17:00:00","SAS 4201","Nikolas Bravo",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1m2bo5jigpkouan5i6bplugf6g","2016-01-26 16:47:41","2016-04-10 11:54:51"
"3384","26","Sensitivity Analysis for a Quantum Informed Ferroelectric Phase Field Model","2016-04-25 16:30:00","2016-04-25 17:00:00","SAS 4201","Lider Leon",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/b321pc4u71seatt140ucnmh2b0","2016-01-26 16:48:50","2016-04-22 11:26:40"
"3385","8","Icosapods and Quartic Spectrahedra","2016-04-12 16:30:00","2016-04-12 17:30:00","SAS 4201","Josef Schicho","https://www.risc.jku.at/people/jschicho/","Johannes Kepler University",,,"Pods are mechanical devices constituted of two rigid bodies, the base and the platform, connected by a number of other rigid bodies, called legs, that are anchored via spherical joints. It is possible to prove that the maximal number of legs of a mobile pod, when finite, is 20. In 1904, Borel designed a technique to construct examples of such $20$-pods, but could not constrain the
legs to have base and platform points with real coordinates. 

Spectahedra are the subsets of semidefinite matrices in some given linear space of symmetric matrices. If the matrices are 4x4 and the space has dimension 4 (quartic spectahedra), then the boundary of the spectahedron is contained in a quartic surfaces, called its symmetroid. Generically, the symetroid has 10 isolated double points with complex cooredinates. The type of a generic quartic spectahedron is the pair of integers (a,b) where a is the number of real double points and b is the number of real double points on the boundary of the spectahedron. The possible types have been identfied by Degtyarev and Itenberg in 2010; Ottem, Ranestad, Sturmfels and Vinzant constructed examples of every possibe type.

In this talk, we present an equivalence of the problem of constructing an icosapod with 20 real legs and the problem of contructing a quartic spectahedron of type (10,0).","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dfe0tsr4nalvpomjcq8mdr98u8","2016-01-27 08:34:24","2016-04-11 16:15:44"
"3386","28","AWM Weekly Lunches and Discussion","2016-01-27 12:30:00","2016-01-27 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/fsft3oje4k2o6ufsuck2dqtgjc","2016-01-27 11:42:21",NULL
"3387","28","AWM Weekly Lunches and Discussion","2016-02-03 12:30:00","2016-02-03 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/u2d3f1tq6id19hhkc6745dn1fg","2016-01-27 11:43:26",NULL
"3388","28","AWM Weekly Lunches and Discussion","2016-02-10 12:30:00","2016-02-10 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/mo0vf3d8lvtrfe7o5qqd89h49s","2016-01-27 11:44:00",NULL
"3389","28","AWM Weekly Lunches and Discussion","2016-02-17 12:30:00","2016-02-17 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4pqapn6h8da6o4tho97utkt468","2016-01-27 11:44:35",NULL
"3390","28","AWM Weekly Lunches and Discussion","2016-02-24 12:30:00","2016-02-24 13:30:00","SAS 4104",,,,,,"Cornelia Van Cott from the University of San Francisco will be joining us this week.  She is the faculty advisor for the Women in Science club at USF.","secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/p4dk4ndo6de2608bgpaep7n3tk","2016-01-27 11:45:12","2016-02-23 09:12:21"
"3391","28","AWM Weekly Lunches and Discussion","2016-03-02 12:30:00","2016-03-02 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4jfo6smiugq3qpnbhe3hrq9vh8","2016-01-27 11:46:13",NULL
"3392","28","AWM Weekly Lunches and Discussion","2016-03-16 12:30:00","2016-03-16 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4ciuie9p7uf18mimeai1pj9mbs","2016-01-27 11:46:51",NULL
"3393","28","AWM Weekly Lunches and Discussion","2016-03-23 12:30:00","2016-03-23 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ucmt4jf0p6o8s5sm8d3u3j9om4","2016-01-27 11:48:27",NULL
"3394","28","AWM Weekly Lunches and Discussion","2016-03-30 12:30:00","2016-03-30 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/9tb3l3q3f9koqln5i87dt7jjs0","2016-01-27 11:49:05",NULL
"3395","28","AWM Weekly Lunches and Discussion","2016-04-06 12:30:00","2016-04-06 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6pkvgsb5o3q7vs548amafe97p4","2016-01-27 11:49:48",NULL
"3396","28","AWM Weekly Lunches and Discussion","2016-04-13 12:30:00","2016-04-13 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/0a85b016jepso6hmj48atpr2s0","2016-01-27 11:50:22",NULL
"3397","28","AWM Weekly Lunches and Discussion","2016-04-20 12:30:00","2016-04-20 13:30:00","SAS 4104",,,,,,,"secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/8kv8522dqpba7qq377fchpk2d0","2016-01-27 11:50:55",NULL
"3398","19","Orbifolds and Cluster Algebras","2016-02-10 16:30:00","2016-02-10 17:30:00","SAS Hall 2102","Shira Polster",,,,,"The talk will introduce new research. Shira will begin by reviewing some background on cluster algebras and cluster algebras from surfaces.","spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6s2hid2e4p73tf9dup3em0b8tc","2016-01-28 12:08:52","2016-02-03 14:50:06"
"3399","3","Reciprocal linear spaces and their Chow forms","2016-02-08 15:00:00","2016-02-08 16:00:00","SAS 4201","Cynthia Vinzant","http://www4.ncsu.edu/~clvinzan/","NC State",,,"A reciprocal linear space is the image of a linear space under coordinate-wise inversion. This nice algebraic variety appears in many contexts and its structure is governed by the combinatorics of an underlying hyperplane arrangement. A reciprocal linear space is also an example of a hyperbolic variety, meaning that there is a family of linear spaces all of whose intersections with it are real. This special real structure is witnessed by a determinantal representation of its Chow form in the Grassmannian. The matrices that appear relate to the boundary operator of certain simplicial complexes.  In this talk, I will introduce reciprocal linear spaces and discuss the relation of their algebraic properties to their combinatorial and real structure. This is based on joint work with Mario Kummer.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n0mr6aa7nf4g9i0dmcbr8l0mlg","2016-01-28 16:20:08",NULL
"3400","10","Perfect Sampling for Queueing Networks","2016-02-02 16:30:00","2016-02-02 17:30:00","Daniels 218","Xinyun Chen",,"Department of Applied Mathematics and Statistics Stony Brook University",,,"Abstract:
 
Perfect sampling is to sample from the stationary distribution of a stochastic process with no bias. In this talk, we present a class of perfect sampling algorithms for queueing networks. We shall start from the most simple M/G/1 queue. Then, applying the Coupling from the Past (CFTP) technique, we develop algorithms for queueing networks of multiple single server queues, including the Fork-Join network and the generalized Jackson network. The algorithms can also be used for gradient simulation, for example, to generate unbiased estimators for the gradient of the expected waiting time with respect to the service rates. The talk is based on joint works with Jose Blanchet and Xianjun Shi.
 
Biography:
 
Xinyun Chen is currently an Assistant Professor in the Department of Applied Mathematics and Statistics at Stony Brook University. She received her Ph.D. in Operations Research at Columbia University, under the supervision of Professor Jose Blanchet. Her research focuses on analytic approximation and numerical computation of stochastic systems, with applications in financial and service engineering.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/u2rh52pr76dincub3d248g1544","2016-02-01 12:12:35",NULL
"3401","2","Emergent Collective Chemotaxis without Single-cell Gradient Sensing","2016-02-03 16:00:00","2016-02-03 17:00:00","Riddick 301","Brian Camley ","http://physics.ucsd.edu/~bcamley/","UCSD",,"https://www.physics.ncsu.edu/department/news/brian_camley.php",,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/agujb7l41t1i8f67nut2r5nkro","2016-02-01 15:36:26","2016-02-01 15:37:18"
"3402","46","On the Center of Mass in General Relativity","2016-03-23 16:00:00","2016-03-23 17:00:00","SAS 4201","Carla Cederbaum","http://www.math.uni-tuebingen.de/arbeitsbereiche/gadr/personen/dr-carla-cederbaum-1/dr-carla-cederbaum","Tuebingen","Andrew Cooper",,"In many situations in Newtonian gravity, understanding the motion of the center of mass of a system is key to understanding the general &quot;trend&quot; of the motion of the system. It is thus desirable to also devise a notion of center of mass with similar properties in general relativity. However, while the definition of the center of mass via the mass density is straightforward in Newtonian gravity, there is a priori no definitive corresponding notion in general relativity. We will take geometric approach to defining the center of mass of a relativistic system in the spirit of a fundamental result by Huisken and Yau from 1996. After introducing their approach, I will discuss explicit counter-examples (joint work with Nerz) and discuss the analytic, geometric, and physical issues they illustrate. I will then present a new approach (joint work with Cortier and Sakovich) that remedies these issues.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5qs67h1og0c7rqjt3g1imhcro8","2016-02-01 21:33:15","2016-02-15 11:48:37"
"3404","1","Machine Learning, Fibre Bundles and Biological Morphology","2016-09-26 16:00:00","2016-09-26 17:00:00","SAS 1102","Ingrid Daubechies","http://fds.duke.edu/db/aas/math/faculty/ingrid/","Duke University",,,"At present, evolutionary anthropologists using physical traits to study evolutionary relationships among living and extinct animals use carefully defined anatomical landmarks to extract information from morphological samples (such as bones and teeth). Identifying and recording these landmarks is time consuming. We are collaborating with evolutionary anthropologists, and in particular building numerical algorithms, to automatically determine biologically relevant distances between pairs of two-dimensional morphological surfaces (embedded in three-dimensional space) that use local structures and global information contained in their geometric relationships. Along with these distance computation, we also obtain geometric correspondences between anatomical surfaces, and analyze morphological data sets using this extra information in a machine learning framework, motivated by the geometric intuition of horizontal diffusion processes on a fibre bundle.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/i3v8b1j3ef5knfs1o11g0iqpic","2016-02-02 10:05:56","2016-05-26 08:47:42"
"3405","21","NOTE CHANGE OF DATE - Kwangil Koh Lecture on Mathematics in Our Time","2016-04-14 16:30:00","2016-04-14 17:30:00","SAS 2203","Tadashi Tokieda",,"Cambridge University",,"http://www.math.ncsu.edu/events/Tokieda.php",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/47dg1ol1scnpojff6gdb4bjdco","2016-02-02 11:44:08","2016-03-21 14:45:27"
"3406","21","Kwangil Koh Lecture on Mathematics in Our Time","2016-09-27 16:30:00","2016-09-27 17:30:00","SAS 2203","Ingrid Daubechies",,"Duke University",,"http://www.math.ncsu.edu/events/Daubechies.php","Mathematicians helping Art Historians and Art Conservators

 

In recent years, mathematical algorithms have helped art historians and art conservators putting together the thousands of fragments into which an unfortunate WWII bombing destroyed world famous frescos by Mantegna, decide that certain paintings by masters were roll mates (their canvases were cut from the same bolt), virtually remove artifacts in preparation for a restoration campaign, get more insight into paintings hidden underneath a visible one,

The presentation will review these applications, and give a glimpse into the mathematical aspects that make this possible.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/p0g6fqsi8fl4pauho359e0ce4g","2016-02-02 11:45:06","2016-05-26 08:48:59"
"3407","2","Modeling network data: adaptive dynamics and higher-order interactions","2016-02-11 14:00:00","2016-02-11 15:00:00","SAS 4201","Bill Shi","http://www.knowledgelab.org/people/detail/feng_bill_shi/","U of Chicago","DDS committee",,"Networks have become a powerful tool in representing and analyzing various complex systems across biological, physical and social sciences. As new technologies allow us to collect data from those systems in high resolution and large scale, existing network models and tools are challenged by the growing complexity of data and corresponding research questions. This talk tackles two related open questions in the field. First, most real systems are not static; system dynamics are constrained by, and simultaneously shape, system structures. To provide a mathematical understanding of the feedback between structures and dynamics, I study an adaptive network model in which opinions diffuse on a network and their dynamics, in turn, modify the structure of the network. I will present various mathematical properties of the model and relate it to a common social phenomenon  polarization. Second, not only are networks dynamic but also involve higher-order interactions of heterogeneous nodes. Such interactions that involve more than two nodes are prevalent in real systems such as chemical reactions, gene-protein interactions, and collaborations. I will show how hypergraphs can be used to study higher-order interactions by generalizing the stochastic block model to hypergraphs. When applied to interactions between chemicals, diseases and methods in biomedical systems, the model reveals large-scale structures of the systems and identifies potential interactions between the constituents.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8k1u18naroh9isosuofn76hlno","2016-02-03 08:50:24","2016-02-03 08:52:22"
"3408","34","Rates of Evolution Among Sperm Genes and Implications for Speciation in a Small Nocturnal Primate, genus Microcebus","2016-03-24 10:00:00","2016-03-24 11:00:00","SAS 4201","Ryan Campbell","https://about.me/c.ryan.campbell","Duke University",,,"The mouse lemurs, genus Microcebus, are 21 species of small nocturnal primates that constitute a 10 million year old evolutionary radiation on the island of Madagascar. Although these primates have been the recent focus of next generation sequencing methods, the initial applications of these data have been centered around understanding the relationships among and between the species rather than the mechanisms that underlie the diversification of the species radiation. There is general consensus that these nocturnal and matrilocal species show low paternal care and a strong propensity towards sperm competition, which is manifested both behaviorally and morphologically during breeding season. High levels of sperm competition between males could in turn reinforce nascent species boundaries. In our study, we compared the rates of positive selection within spermatogenesis-related genes to a set of random non-spermatogenesis genes to determine if the former are evolving faster than the latter. These comparisons were made between several species of Microcebus and show that there are significantly more nonsynonymous base substitutions in spermatogenesis-related genes relative to non-spermatogenesis genes. These results provide molecular data that match our current knowledge of the behavior and lifestyles of these primates. They also highlight what could be an underlying mechanism of speciation among these highly speciose primates of Madagascar.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6khg8q4ogath6ajin81lhrgg6k","2016-02-03 11:55:06","2016-03-14 11:05:21"
"3409","38","Modularity Component Analysis - advised by Carl Meyer","2016-03-25 14:00:00","2016-03-25 15:30:00","SAS 3282","Hansi Jiang",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/vastdicsek2gjde54bnfofm4rc","2016-02-04 14:48:10",NULL
"3410","38","Stability Analysis of Combustion Waves in Porous Media - advised by Stephen Schecter","2016-02-17 15:00:00","2016-02-17 16:30:00","SAS 3282","Fatih Ozbag",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/g5lbs348lr0gq4fmev0j8mrme8","2016-02-04 14:49:41",NULL
"3411","38","Algebraic Geometry of Phylogenetic Models - advised by Seth Sullivant","2016-03-18 15:00:00","2016-03-18 15:00:00","SAS 3282","Colby Long",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/0j30fvlskamj3kiqij742s0i78","2016-02-05 10:22:16",NULL
"3412","4","Semigroup well-posedness for the total linearization of a free boundary hydro-elastic model","2016-03-23 15:00:00","2016-03-23 16:00:00","SAS 4201","Daniel Toundykov",,"University of NebraskaLincoln","Lorena Bociu",,"We will look at a new linearized model of a free boundary fluid-structure interaction. The hydro-elastic equations and the free boundary were linearized together which yields a system quite different from the classical coupling of the Stokes flow and linear elasticity, going back to 1960s. Additional terms emerge on the common interface, some of them involving boundary curvatures. Despite many new features, the system shares a number of properties with the classical model. We proceed to demonstrate that when the linearization is performed around slow steady regimes, the associated evolution operator generates a strongly continuous semigroup. This is a joint work with L. Bociu and Z.-P. Zolesio.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ep02shp8mamdabf2fau50o4npk","2016-02-07 21:41:20","2016-03-20 22:07:25"
"3413","9","Connecting Local and Global Sensitivities in a Mathematical Model for Wound Healing","2016-02-09 16:15:00","2016-02-09 17:15:00","Cox 306","Richard Schugart",,"Mathematics, Western Kentucky University",,,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ttt0ko6vngi03k4eeng7sc8g2g","2016-02-07 22:31:49",NULL
"3414","46","Holomorphization of Path Integrals and Picard-Lefschetz Theory","2016-02-10 16:00:00","2016-02-10 17:00:00","SAS 4201","Alireza Behtash",,"NCSU Theoretical Nuclear & Particle Physics","Radmila Sazdaovic",,"In this talk I will review the holomorphization of path integrals and discuss the semi-classical interpretation of the holomorphized theory. We will observe that this procedure is necessary for finding all saddle solutions that contribute to physical observables of the theory by way of giving explicit examples both from (gauged) supersymmetric quantum mechanics (SQM) and pure mathematics. I will mention briefly about how holomorphization of path integrals is done in configuration space using a very important and powerful tool that will help us along the way, the so-called Picard-Lefschetz theory, which has found a lot of interest in many topics recently.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/69ljdv00rr0hc9b1ovj5j51hkg","2016-02-08 07:07:44","2016-02-10 10:34:39"
"3416","14","Departmental Tea and Cookies","2016-02-11 13:30:00","2016-02-11 14:00:00","SAS 4102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/pmfvcggvlj7ij7f9924rbe9l9s","2016-02-09 14:48:56",NULL
"3417","4","Viscous singular shock profiles for some systems of conservation laws","2016-04-06 15:00:00","2016-04-06 16:00:00","SAS 4201","Ting-Hao Hsu",,"Ohio State University","Xiao-Biao Lin",,"We will discuss singular shocks via the Dafermos regularization $u_t + f (u)_x = \epsilon tu_{xx}$ for systems of conservation laws in one space dimension. For a system modeling incompressible two-phase fluid flow, we will show that, when the Riemann data is over-compressive, the viscous solution becomes unbounded and approaches the sum of a step function and a Dirac delta function supported on a shock curve. This limit is called a singular shock, and the family of viscous solutions is called a viscous profile. We will also discuss the Keyfitz-Kranzer system, for which the existence of viscous singular shock profiles has been proved by S. Schecter in 2004. In this talk we will show an enhanced version of that result, which confirms the weak convergence as well as describes the asymptotic behavior of the viscous solution. The viscous solution for the two-phase flow has a maximum of order $\exp(\epsilon^{-1})$, and that for the Keyfitz-Kranzor system is of order $\epsilon^{-2}$.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/lbdusbrm1lgmsbkarrhc6t4b7g","2016-02-09 17:49:33","2016-02-13 15:03:26"
"3418","4","Causes of Metastability and Their Effects on Transition Times","2016-04-13 15:00:00","2016-04-13 16:00:00","SAS 4201","Katie Newhall",,,"Lorena Bociu",,"Many experimental systems can spend extended periods of time relative to their natural time scale in localized regions of phase space, transiting infrequently between them.  This display of metastability can arise in stochastically driven systems due to the presence of large energy barriers, or in deterministic systems due to the presence of narrow passages in phase space.  As an example spatially extended system, we investigate a stochastic Langevin equation that limits to a stochastic partial differential equation as the dimension goes to infinity.  We analyze the effects of small damping, small noise, and dimensionality on the dynamics and mean transition times.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/cmoinpf9tvjjv78018rddhvav0","2016-02-10 11:49:44",NULL
"3419","46","Stability for the multidimensional rigid body via singular curves","2016-03-18 14:00:00","2016-03-18 15:00:00","SAS 2229","Anton Izosimov","https://www.math.toronto.edu/cms/izosimov-anton/","University of Toronto","Irina Kogan",,"A classical result of Euler says that the rotation of a torque-free 3-dimensional rigid body about the short or the long axis is stable, while the rotation about the middle axis is unstable. I will present a multidimensional generalization of this result and explain how it can be proved using basic algebraic geometry of singular curves.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ufkekuahgat8q6jdj2fsbaf8q0","2016-02-10 18:59:14","2016-02-25 11:09:24"
"3421","19","Combinatorics of L-infinity optimization to linear spaces","2016-02-24 16:30:00","2016-02-24 17:30:00","SAS Hall 2102","Dan Bernstein",,,,,"Daniel will discuss how oriented matroids can be used to describe the set of points in a linear space that are nearest to a given point in the L-infinity norm. A nice consequence is that every point x has a unique L-infinity nearest neighbor in a linear space S if and only if the matroid underlying S is uniform. I will also discuss motivation from phylogenetics. This is joint work with Colby Long and Seth Sullivant.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/osi7v57bdpda3un45di7rg3ta8","2016-02-10 21:20:40","2016-02-22 09:46:21"
"3422","19",,"2016-03-02 16:30:00","2016-03-02 17:30:00","SAS Hall 2102","McKay Sullivan",,,,,"The first 20-30 minutes will be a demonstration of how to construct free field vertex algebras using a Fock space representation of an infinite-dimensional Lie algebra. Ill make this part of the talk as accessible as I can. For those who want to stick around, during the last 20 minutes I will practice presenting slides that I intend to use at a conference this weekend. The goal of the slides is to give an example of a twisted logarithmic module of the symplectic fermion vertex algebra. This is done using a construction similar to that shown in the first portion of the talk.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jmfp4qbcqrhu8o4abam05u23kc","2016-02-10 21:22:03","2016-03-01 16:35:33"
"3424","19",,"2016-03-23 16:30:00","2016-03-23 17:30:00","SAS Hall 2102","Emily Barnard",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/46m70bfuisg3b2s6g14unk6v50","2016-02-10 21:25:51",NULL
"3425","19",,"2016-03-30 16:30:00","2016-03-30 17:30:00","SAS Hall 2102","Dan Scofield",,,,,,"esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fqjjrcpapm5nlg9bl2g5pv58do","2016-02-10 21:26:33",NULL
"3426","19",,"2016-04-13 16:30:00","2016-04-13 17:30:00","SAS Hall 2102","Anila Yadavalli",,,,,"In this talk I will be introducing Bosons and Fermions. It will be very accessible.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/tls7l6vq73g29qqq1tf7vhs974","2016-02-10 21:27:49","2016-04-11 09:45:37"
"3427","14","DELTA information session","2016-03-01 16:15:00","2016-03-01 17:15:00","SAS 4201","DELTA",,,"Pierre Gremaud",,"As part of our effort to start a distance education (DE) graduate certificate, we are organizing a meeting between those of you interested in exploring online teaching and the experts at DELTA. The meeting will take place in the Math Department and its format will be that of a short presentation from DELTA followed by a Q&amp;A.

We plan on covering the following topics:

-What kind of help can DELTA provide to individual instructors?
-How flexible is the &quot;online format&quot; and will this fit my/your course(s) and teaching style?
-How much work is it to develop a DE course and what does that involve?
-How much work is it to run a DE course?
-etc...","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/fh0iafptk53262elgmsg3ptddg","2016-02-12 10:04:58",NULL
"3428","26","Disentangling Causation and Correlation; a simple case study with infection modeling","2016-02-22 16:00:00","2016-02-22 17:00:00","SAS 4201","Ethan King",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nh5rdh1n112ppp9ga9jsq23dl8","2016-02-15 17:40:17",NULL
"3429","14","Departmental Tea and Cookies","2016-02-17 14:30:00","2016-02-17 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/q4gk1800lvutgna6231tos8iq8","2016-02-16 11:03:26",NULL
"3431","22","Sometimes Pi Equals 4","2016-02-25 16:30:00","2016-02-25 17:30:00","SAS 2120","Cornelia Van Cott ","https://www.usfca.edu/faculty/cornelia-van-cott","University of San Francisco","Radmila Sazdaovic",,"Youve spent your whole mathematical life believing that pi is an irrational number somewhere between 3.14 and 3.15. But under certain conditions, pi equals 4. And if that didnt surprise you, consider this: pi can, in fact, be any of an infinite number of different values, depending on ones choice of metric. With this new information, the all-important question is: when can we celebrate Pi Day? Come and find out! This talk will be accessible to all undergraduates.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/imlpr7i76ocl8vsvt8fgcsd4tc","2016-02-16 22:47:18","2016-02-19 23:04:59"
"3432","14","Faculty Meeting: report of the Data Driven Science Cluster Committee","2016-02-18 15:00:00","2016-02-18 16:00:00","SAS 4201",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/mvt91i2k740seck84jht5q2u1c","2016-02-17 11:18:33","2016-02-18 11:45:13"
"3433","4","Linearized Hydro-Elasticity:  A Numerical Study","2016-02-24 15:00:00","2016-02-24 16:00:00","SAS 4201","Steven Derochers",,"NC State",,,"In view of control and  stability theory, a new linearization around a steady state of a fluid-structure interaction model is considered. The linearization is performed with respect to an external forcing term and was obtained in [Bociu-Zolesio, 2013], using shape optimization techniques, which are most suited to incorporating the geometry of the problem into the analysis. This refined description brings up new termsmissing in the classical coupling of linear Stokes flow and linear elasticityin the matching of the normal stresses and velocities on the interface. It was recently shown in [Bociu-Toundykov-Zolesio,2015] that this linear PDE system generates a C_0 semigroup, but, unlike in standard Stokes-elasticity coupling, the well-posedness result is highly dependent on the fluids viscosity and the new  boundary terms which, among other things,  involve the curvature of the interface. In this talk, we discuss the implementation of a finite element scheme for approximating solutions of this fluid-elasticity dynamics and the numerical investigation of the dependence of the discretized model on the new terms present therein, in contrast with the classical Stokes-linear elasticity system.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nnck7iu67h8176gbk9ktn9ibs8","2016-02-17 15:11:24","2016-02-17 15:13:12"
"3434","46","Lagrangian Flows, Maslov Index Zero, and Special Lagrangians.","2016-04-20 16:00:00","2016-04-20 17:00:00","4201 SAS Hall","Jon Wolfson","http://users.math.msu.edu/users/wolfson/","Michigan State","Andrew Cooper",,"The talk introduces lagrangian geometry and discusses work in progress on the construction of a &quot;flow&quot; of singular lagrangian submanifolds.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/koo84udpgione1oi11a0jh0acs","2016-02-18 15:59:24","2016-04-18 10:31:27"
"3436","3","Coordinates on the decorated super-Teichmueller spaces","2016-04-18 15:00:00","2016-04-18 16:00:00","SAS 4201","Anton Zeitlin","http://math.columbia.edu/~zeitlin/","Columbia University",,,"I will talk about the construction of the generalization of Penners coordinates on the decorated super-Teichmueller space of a surface with s greater than or equal to 1 punctures, which is a principal bundle over the corresponding super-Teichmueller space. We will discuss all necessary ingredients e.g. super-version of the Ptolemy transformations, combinatorial approach to the description of the spin structures on punctured surfaces as well as the even Ptolemy-invariant 2-form, which is the generalization of the Weil-Petersson 2-form. If time allows, the analogue of this coordinates on higher super-Teichmueller spaces will be discussed.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9uh9mgctul1k663ad0u211u940","2016-02-18 16:20:20","2016-04-06 20:55:35"
"3438","22","Modeling the European refugee crisis in 96 hours","2016-03-31 16:30:00","2016-03-31 17:20:00","SAS 2102","Kenneth Jutz, Graham Pash, and Jaye Sudweeks",,,,"https://web.math.ncsu.edu/sumseries/spring2016/033116.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/h6hm8kok465kqv658qarujghmc","2016-02-22 10:47:41",NULL
"3439","8","How to compute good rational parametrizations?","2016-04-19 16:30:00","2016-04-19 17:30:00","SAS 4201","Rafael Sendra","http://www3.uah.es/rsendra/index.html","University of Alcala, Spain",,,"There exist algorithms to compute rational parametrizations of rational curves and surfaces. These rational parametrizations are not unique, and hence the question of determining a simpler, or even the simplest, parametrization of a given curve or surface arises. In this talk we will motivate the problem, we will discuss different criteria for simplicity (injectivity, surjectivity, field of parametrization, height), and we will describe the basic ideas of some of the existing approaches.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/f880u7ik42mjij8tnqslpshvf4","2016-02-22 12:45:45","2016-04-10 18:25:14"
"3440","14","Departmental Tea and Cookies","2016-02-24 14:30:00","2016-02-24 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/lb6f50j5jhir469l693gd9078o","2016-02-22 13:26:12",NULL
"3441","14","Departmental Tea and Cookies","2016-03-02 14:30:00","2016-03-02 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/lmmru8idk52fjb93udfrm368ck","2016-02-22 13:27:00",NULL
"3442","14","Departmental Tea and Cookies","2016-03-16 14:30:00","2016-03-16 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/29lm3kvho667los6fvkr5777n0","2016-02-22 13:27:47",NULL
"3443","14","Departmental Tea and Cookies","2016-03-23 14:30:00","2016-03-23 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/pktpueaaou77hgshtv237n9hfo","2016-02-22 13:28:36",NULL
"3445","14","Dr. Haider  and Dr. Gremaud Reception","2016-04-13 14:30:00","2016-04-13 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/22vla882s9cnlqoe38oihhro38","2016-02-22 13:30:46","2016-04-11 10:19:43"
"3446","14","Departmental Tea and Cookies","2016-04-20 14:30:00","2016-04-20 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/822aj4dnidefoo78sfe7l6lnig","2016-02-22 13:32:05",NULL
"3448","14","Departmental Tea and Cookies","2016-04-07 15:30:00","2016-04-07 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/cq833h3e0inp42gf7pb32il2ns","2016-02-22 13:34:59",NULL
"3450","4","Balance laws related to a stochastic representation of solutions to systems of quasilinear equations","2016-03-16 15:00:00","2016-03-16 16:00:00","SAS 4201","Olga Rozanova",,"Moscow State University","Alina Chertock",,"We show that an asymptotic representation of  smooth solutions to the Cauchy problem for any genuinely nonlinear hyperbolic system of equations written in the Riemann invariants can be obtained by a method of stochastic perturbation of the associated Langevin system. On this way we associate with the stochastically perturbed equations a system of viscous balance laws.   Till the moment of the shock formation the above system of viscous balance laws can be reduced to the pressureless gas dynamics system (in a limit as the parameters of perturbation tend to zero). If the solution to the initial system  contains shocks, the limit system is equivalent to the system with a specific pressure, in some sense analogous to the pressure of barotropic monoatomic gas. Based on the solution of this auxiliary system we give a definition of a generalized solution of the initial hyperbolic system in the sense of &quot;free particles.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/tblmjuso2ampe10ghqpcsmdkvk","2016-02-22 22:49:12",NULL
"3452","6",,"2016-04-26 15:00:00","2016-04-26 16:00:00","SAS 4201","TBA Queries to Tim Kelley ","TBA",,,,"Room reserved for special seminar.","ctk","0",,"2016-02-25 09:40:35",NULL
"3453","38","Some Criteria for Solvable and Supersolvable Leibniz Algebras - advised by Kailash Misra &amp; Ernie Stitzinger","2016-03-16 15:00:00","2016-03-16 16:30:00","SAS 3282","Bethany Turner",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/p07n3jphtttroruj9rqkrchigc","2016-02-26 10:59:05",NULL
"3454","4","Emergent dynamics from network connectivity: a minimal model","2016-04-20 15:00:00","2016-04-20 16:00:00","SAS 4201","Carina Curto","http://www.personal.psu.edu/cpc16/","Penn State University","Lorena Bociu",,"Many networks in the brain display internally-generated patterns of activity -- that is, they exhibit emergent dynamics that are shaped by intrinsic properties of the network rather than inherited from an external input.  While a common feature of these networks is an abundance of inhibition, the role of network connectivity in pattern generation remains unclear.

In this talk I will introduce Combinatorial Threshold-Linear Networks (CTLNs), which are simple &quot;toy models&quot; of recurrent networks consisting of threshold-linear neurons with binary inhibitory interactions.  The dynamics of CTLNs are controlled solely by the structure of an underlying directed graph.  By varying the graph, we observe a rich variety of emergent patterns including: multistability, neuronal sequences, and complex rhythms.  These patterns are reminiscent of population activity in cortex, hippocampus, and central pattern generators for locomotion.  I will present some theorems about CTLNs, and explain how they allow us to predict features of the dynamics by examining properties of the underlying graph.  Finally, Ill show examples illustrating how these mathematical results guide us to engineer complex networks with prescribed dynamic patterns.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/kbu47s68cevoclq2213ij24k4c","2016-02-28 20:35:04","2016-04-08 13:35:05"
"3455","8","Tropical Varieties for Exponential Sums","2016-03-29 16:30:00","2016-03-29 17:30:00","SAS 4201","Alperen Ergur","http://www.math.tamu.edu/~alperen/","Texas A&M",,,"We define a variant of tropical varieties for exponential sums. These polyhedral  complexes can be used to approximate, within an explicit distance bound, the real parts of complex zeroes of exponential sums. We also discuss the algorithmic efficiency of tropical varieties in relation to the computational hardness of algebraic sets.  This is joint work with Maurice Rojas and Grigoris Paouris.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fhm0sc6fhqcnvmjeu753st2924","2016-02-29 07:55:09","2016-03-29 10:40:12"
"3456","22","Deblurring: seeing what is invisible to others","2016-03-03 16:30:00","2016-03-03 17:20:00","SAS 2102","Arvind Saibaba","http://www4.ncsu.edu/~asaibab/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2016/030316.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ligfaop8q2nhcqig6ekrfo51n0","2016-02-29 09:35:33",NULL
"3457","22","How Ramsey ruined parties forever","2016-03-17 16:30:00","2016-03-17 17:20:00","SAS 2102","Felix Reidl","http://tcs.rwth-aachen.de/~reidl/","NC State",,,"They say there are few unavoidable things in life -- e.g. taxes (and finals!).  In mathematics, however, unavoidable things are rather common. In 1930, F. P. Ramsey found a particularly beautiful case of unavoidability which has deep implications for number theory, combinatorics, information theory and many other fields. In this SUM talk, we will get to know how graphs, Ramsey theory and the probabilistic method tell us another unavoidable thing in life: namely, why large parties will always be awkward for some of the guests.

This talk will not assume any prior knowledge in graph theory and will be accessible to all undergraduates.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/baac7gj9dc94l66t79r2mlilj4","2016-02-29 09:38:06","2016-03-14 16:22:24"
"3458","22","Vector graphics 101","2016-03-22 16:30:00","2016-03-22 17:20:00","SAS 2102","Daniel Toundykov","https://sites.google.com/site/danieltweb/","University of Nebraska Lincoln",,,"I will introduce the rudiments of programming and animating 3D vector objects with some implementation examples. There will be a little bit of calculus, some matrix algebra (no prior knowledge required), 3D stick figures and even breakdancing spiders!","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0st9uu6ogm6bfkf1ue8pgb3gk4","2016-02-29 09:40:13","2016-03-15 10:14:29"
"3459","22","The mathematics of voting","2016-04-07 16:30:00","2016-04-07 17:20:00","SAS 2102","Molly Fenn","http://www4.ncsu.edu/~mafenn2/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2016/040716.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/f4vmk864t5k5ih4dt82cqpinlk","2016-02-29 09:41:45","2016-04-03 21:47:21"
"3460","14","Departmental Tea and Cookies","2016-03-15 14:30:00","2016-03-15 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/9kftjm5npaotgd6d48hi8gepm0","2016-03-02 10:41:34",NULL
"3462","38","A Theoretical Analysis of Anderson Acceleration and its Application in Multiphysics Simulation for Light-Water Reactors - advised by Tim Kelley","2016-03-29 14:00:00","2016-03-29 15:30:00","SAS 3282","Alex Toth",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/031hube2n6go94i1tll8l54tlk","2016-03-04 10:14:14","2016-03-04 10:14:57"
"3463","3","Combinatorics of involution Schubert polynomials","2016-03-28 15:00:00","2016-03-28 16:00:00","SAS 4201","Brendan Pawlowski","http://www-personal.umich.edu/~pawlows/","University of Michigan",,,"Wyser and Yong have described polynomials representing the cohomology classes of O(n)- and Sp(n)- orbit closures (indexed by involutions) on the complete flag variety. We investigate analogues of Schubert combinatorics for these involution Schubert polynomials. The role of reduced words is played by what we call involution words, studied under other names by various authors starting with Richardson and Springer. Many familiar aspects of Coxeter combinatorics transfer to this setting. In the O(n)-case, we also describe analogues of Edelman-Greene insertion and Lascoux-Schutzenbergers transition equations, and use these to show that stable involution Schubert polynomials are Schur-P-positive. As a special case, the transition equations give a new Littlewood-Richardson rule for Schur P-functions. This is joint work with Zach Hamaker and Eric Marberg.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5125bbnliq2cepurttk77vll18","2016-03-04 15:20:59","2016-03-19 14:55:18"
"3464","4","Stochastic Three-Dimensional Rotating Navier-Stokes Equations: Averaging, Convergence and Regularity","2016-09-21 15:00:00","2016-09-21 16:00:00","SAS 4201","Alex Mahalov",,"Arizona State","Semyon Tsynkov",,"We consider stochastic three-dimensional rotating Navier-Stokes equations and prove averaging theorems for stochastic problems in the case of strong rotation. Regularity results are established by bootstrapping from global regularity of the limit stochastic equations and convergence theorems. The energy injected in the system by the noise is large, the initial condition has large energy, and the regularization time horizon is long. Regularization is the consequence of a precise mechanism of relevant three-dimensional nonlinear interactions. We establish multiscale averaging and convergence theorems for the stochastic dynamics. References [1] Flandoli F. , Mahalov A. , Stochastic 3D Rotating Navier-Stokes Equations: Averaging, Convergence and Regularity, Archive for Rational Mechanics and Analysis, 205, No. 1, 195237 (2012). [2] Cheng B. , Mahalov A. , Euler Equations on a Fast Rotating Sphere  Time- Averages and Zonal Flows, European Journal of Mechanics B/Fluids, 37, 48-58 (2013). [3] Mahalov A. Multiscale modeling and nested simulations of three-dimensional ionospheric plasmas: Rayleigh-Taylor turbulence and nonequilibrium layer dynamics at fine scales, Physica Scripta, Phys. Scr. 89 (2014) 098001 (22pp), Royal Swedish Academy of Sciences.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nlnd4d3c5i8ib0aqhu8q3bddck","2016-03-08 11:02:37","2016-08-30 09:51:15"
"3466","15","Guest Speaker","2016-03-23 11:00:00","2016-03-23 12:00:00","Mann 404","Daniel Toundykov",,"University of Nebraska Lincoln",,,,"allewis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/e85idg7sb8cqt2pijf88u7rivk","2016-03-09 22:26:04",NULL
"3467","15","Guest Speaker","2016-04-13 11:00:00","2016-04-13 12:00:00","Mann 404","Katie Newhall",,"University of North Carolina",,,,"allewis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/pc5i5a0l0gb9hcrfvmsscct7jc","2016-03-09 22:27:05",NULL
"3468","8","Sparse Polynomial Interpolation and Testing","2016-03-15 16:30:00","2016-03-15 17:30:00","SAS 4201","Andrew Arnold ","https://cs.uwaterloo.ca/~a4arnold/","NC State",,,"Polynomial interpolation, i.e., learning a polynomial f via its evaluations, is the basis of fast polynomial arithmetic.  In this talk, we will give probabilistic algorithms that expedite interpolation when f is known to have at most T terms, in which case we say f is T-sparse.  We also discuss the closely related problem of sparsity testing: deciding whether f is T-sparse.  Using techniques from sparse interpolation and sparsity testing, we give a Monte Carlo algorithm that improves on the worst-case complexity for the multiplication of sparse polynomials with integer coefficients.  We also discuss related techniques for multivariate polynomials; as well error-correcting sparse interpolation, wherein we allow for a bounded number of erroneous evaluations.  This talk is based on joint projects with Mark Giesbrecht, Erich Kaltofen, and Daniel Roche.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/h5j6em875mfpaqhlgip0ujei5g","2016-03-10 11:12:12",NULL
"3469","10","A Fluid Model for an Overloaded Bipartite Queueing System with Scoring-Based Priority Rules","2016-03-15 16:30:00","2016-03-15 17:30:00","Daniels 218","Yichuan Ding",,"Sauder Business School, University of British Columbia",,,"Abstract:
 
We consider an overloaded bipartite queueing system (BQS) with multitype customers and service providers. In such a system, a service provider assigns each customer a score based on customer type, duration of waiting time, and server type. Service is then provided to the customer with the highest score. We approximate the behavior of such a system using a fluid limit process, which has two important features: (1) the routing flow rates at a transient state coincide with the maximal flow in a parameterized network and can be efficiently computed based on a nested-cut structure using a so-called GGT algorithm; (2) the routing flow rates in the steady state coincide with the minimal-cost maximal-flow in a capacitated network. Given these properties, we can efficiently characterize the unique fluid limit process. This result has three immediate applications: (1) it predicts the performance of an overloaded BQS equipped with a scoring-based routing policy; (2) it sheds insight into how to design a score formula that meets a given set of objectives; (3) by applying the result to the special case when the BQS is FCFS, we partially address the open question raised by \citet{Whitt2008}. We illustrate the application of our machinery in a real-life application --- public housing assignment.
 
Biography:
 
Yichuan Ding is currently an assistant professor from the Sauder School of Business, University of British Columbia. He obtained his Ph.D. degree from the Department of Management Science and Engineering, Stanford University in 2012. He researches broadly in operations research methods and their applications in production and service systems. During his doctoral study, he worked with Stefanos Zenios on health care problems, including the design of kidney allocation policy, patient flow management, and graft survival forecasting. He also worked on semidefinite programming and stochastic optimization, with results published on Mathematics of Operations Research, and Operations Research. He has participated in consulting projects from industries and hospitals, including the Boeing Company, IBM research, the Scientific Registration of Transplant Research, and the San Francisco General Hospital.
 
 
Refreshments will be served in 401 Daniels from 4:00 p.m.  4:30 p.m","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qhjpvh1st87r96lvsv4g3k5cpk","2016-03-11 10:35:34",NULL
"3470","38","Some geometric aspects of hyperbolic conservation laws - advised by Irina Kogan","2016-04-29 09:30:00","2016-04-29 11:00:00","SAS 3282","Michael Benfield",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ng4ca30o16tievcthj1t947cb8","2016-03-14 09:32:34",NULL
"3472","2","Interview lecture on Fourier transforms","2016-03-15 15:00:00","2016-03-15 16:00:00","SAS 4201","Mary Clair Thompson","http://sites.lafayette.edu/thompsmc/","Lafayette College","TAP hiring committee",,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4aklcbgsg9q6rorf7hv1b0brn8","2016-03-14 14:14:42","2016-03-14 14:15:32"
"3473","2","Interview lecture on line integrals","2016-03-16 15:00:00","2016-03-16 16:00:00","SAS 2102","Amy Macrina",,"Northern Virginia Community College ","TAP hiring committee",,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6vkievflk2hkhlqe5mi9ohv984","2016-03-14 14:23:54",NULL
"3475","3","The two bosonizations of type C","2016-04-25 15:00:00","2016-04-25 16:00:00","SAS 4201","Iana Anguelova","http://math.cofc.edu/about/faculty-staff-listing/anguelova-iana.php","College of Charleston",,,"The name bosonization refers to the representation of given chiral fields (vertex operators) via  bosonic fields. The  instances  of bosonization are rare,  and are especially valuable for their   applications to integrable systems and representation theory. The  best known  is the bosonization of the charged free fermions: one of the two directions of an  isomorphism often referred to as &quot;the&quot; boson-fermion correspondence (of type A). In this talk we will discuss the case of type C, so named because of its connection to the CKP hierarchy.  Remarkably, there is not one, but two bosonizations of  type C: one via a twisted Heisenberg field, and another via an untwisted Heisenberg field.  We will discuss some of the applications, in particular the  connections to combinatorics via the various graded dimensions (character formulas).","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/l0557q1m7gndnu65tso5smpsgo","2016-03-14 14:42:06","2016-04-11 20:14:57"
"3476","21","5th Annual Sonia Kovalevsky Day","2016-04-02 08:00:00","2016-04-02 12:00:00","SAS Hall",,,,,"https://www.math.ncsu.edu/forms/AWM/app/index.php","The Association for Women in Mathematics Student Chapter at NC State will be hosting their 5th Annual Sonia Kovalevsky Day on the morning of Saturday, April 2nd. 

The event will involve mathematically-oriented games and workshops and a keynote talk. This event is free, and any 7th and 8th grade girls are welcome to attend. The deadline for registration is Wednesday, March 30th&amp;#8203;&amp;#8203;. Parents can register their daughters using the following link:

&lt;a href=&quot;https://www.math.ncsu.edu/forms/AWM/app/index.php&quot;&gt;Registration Form&lt;/a&gt;

A poster and schedule of the event are attached. Please feel free to display the poster and also to forward this email to anyone who might be interested in the event. 

Please feel free to contact Kristina Martin (president of AWM@NCSU)  at kmmarti6@ncsu.edu with any questions.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/lh3lglmhc3fuif7f7oj2lst774","2016-03-16 11:49:54",NULL
"3477","38","Gradient-free active subspace construction and model calibration techniques for complex models - advised by Ralph Smith","2016-05-19 10:00:00","2016-05-19 11:30:00","SAS 3282","Allison Lewis",,"NC State",,,,"allewis2","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/4qdn1pcfp9kd8a60toc24dfgbg","2016-03-17 09:21:13","2016-05-15 18:24:57"
"3478","9","Multi-scale modeling in ionic gels and particle aggregation","2016-03-22 16:15:00","2016-03-22 17:15:00","Cox 306","Sarthok Sircar","http://www.maths.adelaide.edu.au/sarthok.sircar/","School of Mathematical Sciences, University of Adelaide","Mansoor Haider",,"Multi-scale modeling in ionic gels and particle aggregation

Sarthok Sircar
School of Mathematical Sciences, University of Adelaide

Abstract: Most of todays experimentally verifiable scientific research, not only requires us to resolve the physical features over several spatial and temporal scales but also demand suitable techniques to bridge the information over these scales. In this talk I will provide 2 examples in mathematical biology to describe these systems at 2 levels: the meso/micro level and the continuum/macro level. I will then detail suitable tools in statistical mechanics to link these different scales.

The first problem arises in mathematical physiology: swelling-de-swelling mechanism of mucus, an ionic gel. Mucus is packaged inside cells at high concentration (volume fraction) and when released into the extracellular environment, it expands in volume by two orders of magnitude in a matter of seconds. This rapid expansion is due to the rapid exchange of calcium and sodium that changes the cross-linked structure of the mucus polymers, thereby causing it to swell. Modeling this problem involves a two-phase, polymer/solvent mixture theory (in the continuum level description), together with the chemistry of the polymer, its nearest neighbor interaction and its binding with the dissolved ionic species (in the micro-scale description). The problem is posed as a free-boundary problem, with the boundary conditions derived from a combination of variational principle and perturbation analysis. The dynamics of neutral gels and the equilibrium-states of the ionic gels are analyzed.

In the second example, we numerically study the adhesion fragmentation dynamics of bacteria (or in general: rigid, round particles) clusters subject to a homogeneous shear flow. In the macro level we describe the dynamics of the number density of these cluster. The description in the micro-scale includes (a) binding/unbinding of the bonds attached on the particle surface, (b) bond torsion, (c) surface potential due to ionic medium, and (d) flow hydrodynamics due to shear flow.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8817l9v9sgnmd2p3bb6av6odv4","2016-03-17 10:01:26","2016-03-17 10:20:54"
"3479","9","Traveling waves of data-validated density-dependent diffusion models of glioblastoma growth","2016-04-12 16:15:00","2016-04-12 17:15:00","Cox 306","Yang Kuang","https://math.la.asu.edu/~kuang/","School of Math and Statistical Sciences, Arizona State University","Kevin Flores",,"Glioblastoma multiforme (GBM) is an aggressive brain cancer that is extremely fatal.  It is characterized by both proliferation and large amounts of migration, which contributes to the difficulty of treatment.  Most existing models of this type of cancer growth often include two separate equations to model proliferation or migration.  To better understand the interaction of the cell proliferation and migration exhibited in an in vitro GBM cell growth experiment, we propose two biologically plausible models that are also mathematically tractable. The first model consists of a single equation which uses density-dependent diffusion to capture the behavior of both proliferation and migration. We analyze the model to determine the existence of traveling wave solutions. To establish the viability of the density-dependent diffusion function chosen, we compare our model with the in vitro experimental data. The second model consists of two equations and is based on the well received modeling assumption that cells either grow or go away. We establish the minimum wave speed analytically for these models and compare the analytical results with simulation findings. We will also present some biological insights and mathematical open questions derived from these models.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ul7num2nj89kqqjj5fif5m6kkk","2016-03-17 10:22:37","2016-03-20 23:00:14"
"3480","21","Graduate Student Modeling Workshop (IMSM 2016)","2016-07-17 08:00:00","2016-07-27 17:00:00","SAS Hall, NC State",,,,"Ipsen, Gremaud, SMith","http://www.samsi.info/workshop/2016-industrial-mathstat-modeling-workshop-graduate-students-july-17-27-2016","The 22nd Industrial Mathematical &amp; Statistical Modeling (IMSM)
Workshop for Graduate Students will take place at North Carolina State
University, 17-27 July 2016.  The workshop is sponsored by the
Statistical and Applied Mathematical Science Institute (SAMSI)
together with the Center for Research in Scientific Computation (CRSC)
and the Department of Mathematics at North Carolina State University.

The IMSM workshop exposes graduate students in mathematics,
engineering, and statistics to exciting real-world problems from
industry and government. The workshop provides students with
experience in a research team environment and exposure to possible
career opportunities. On the first day, a Software Carpentry bootcamp
will bring students up-to-date on their programming skills in Python/Matlab and R,
and introduce them to version control systems and software repositories.

Local expenses and travel expenses will be covered for students at US institutions.
The application deadline is 15 May 2016.
Information is available at http://www.samsi.info/IMSM16
and questions can be directed to grad@samsi.info","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/v2a558u3mrl8pvjlkv11fbakh0","2016-03-21 09:31:31","2016-04-20 12:34:03"
"3481","3","Associative algebras and logarithmic twisted modules","2016-10-17 15:00:00","2016-10-17 16:00:00","SAS 4201","Jinwei Yang","http://math.nd.edu/people/visiting-faculty/jinwei-yang/","University of Notre Dame",,,"We construct an associative algebra from a vertex operator algebra V and a general automorphism g of V, which is a generalization of g-twisted version of the Zhu algebra introduced by Dong, Li and Mason when the order of g is finite. Our main interest is the case that g is infinite order and does not act on V semisimply. We construct functors between the category of modules for these associative algebras and the category of (logarithmic) g-twisted V-modules. This is a joint work with Yi-Zhi Huang.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/972c05b3rd11vjoie664u1koa8","2016-03-21 14:19:34","2016-10-12 11:08:16"
"3482","9","Modeling HIV infection and treatment - abortive infection and latency reversal","2016-04-19 16:15:00","2016-04-19 17:15:00","SAS 1102","Ruian Ke",,"NC State, Department of Mathematics",,,"Modeling HIV infection and treatment - abortive infection and latency reversal

Ruian Ke
Department of Mathematics, NC State University

Each year, millions of individuals infected with human immunodeficiency virus (HIV) die of AIDS globally. Currently, we still do not have a scalable medical intervention to cure HIV infection. Two important issues underlie the difficulties in preventing AIDS development and curing HIV infections: 1) the lack of knowledge of the mechanism that drives progressive depletion of CD4+ T cells (a target for HIV infection and an important component of the immune system) that ultimately leads to AIDS and 2) the difficulty to purge the population of CD4+ T cells latently infected by HIV. In this talk, I will present two works addressing these two issues through mathematical modeling. In the first part, I will present our work on treatment strategies using latency reversing agents, a class of drugs that aims to reverse HIV latency, to purge the population of latently infected cells and ultimately achieve a cure. In the second part, I will present our work on quantifying the rate of CD4+ T cell death triggered by abortive infection, a route recently suggested to be a major pathway of T cell depletion. I will also discuss implications of our works in terms of fundamental understanding of HIV biology and treatment strategies.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/61ohm6ctfdr4r28tot6brj44do","2016-03-22 10:27:24","2016-04-13 10:02:23"
"3483","2","Interview lecture","2016-03-28 15:00:00","2016-03-28 16:00:00","SAS 2102","Bevin Maultsby",,"U of Minnesota","TAPDE hiring committee",,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sldq4kmf6l2fj4vnaqmmec7768","2016-03-22 11:46:43",NULL
"3484","14","Departmental Tea and Cookies","2016-03-28 14:30:00","2016-03-28 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/f6h1o1flaf99663so33m98q6pg","2016-03-22 14:28:49",NULL
"3485","9","Mathematical models for understanding phenotypic heterogeneity and plasticity of cells","2016-03-25 11:00:00","2016-03-25 12:00:00","CVM C120 Main Building  Centennial Biomedical Campus College of Veterinary Medicine at NC State","Tian Hong",,"Postdoctoral Scholar  University of California, Irvine",,"http://www.math.ncsu.edu/events/Tian_Hong.pdf","The development and function of tissues in multicellular organisms rely on specialization of cellular phenotypes. This phenotypic 
heterogeneity needs to be generated via cell differentiation and maintained in a highly regulated manner. In addition, the dynamic nature of many biological processes, such as tissue regeneration and immune responses, often entails phenotypic plasticity of cells, also known as transdifferentiation. The complexity of these processes requires quantitative modeling for interactions among molecular species and cellular components, relating dynamic features of the intrinsic design of the cells to the behaviors of the cells and tissues. In this talk, I will discuss role of models in understanding heterogeneity and plasticity of cells using three biological systems that I recently studied: 1) heterogeneous differentiation of CD4+ T cells, 2) multi-step epithelial-to-mesenchymal (EMT) transitions and 3) spatiotemporal regulation of motor neuron subtype specification. Computational analysis of these models have led to several new discoveries including delineation of critical roles for interconnected feedback loops in producing multiple intermediate states during phenotypic transitions and the importance of these multistep transitions.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fuetfpg6qmvb8t5li1dppqomv4","2016-03-23 10:53:41","2016-03-23 10:58:34"
"3487","26","Mathematical Model of Hepatitis C Viral Dynamics using a Combination Therapy of Interferon, Ribavirin, and Telaprevir","2016-03-28 16:30:00","2016-03-28 17:00:00","SAS 4201","George Lankford",,"NC State",,,"Hepatitis C is a virus that affects the liver and is one of the leading causes for cirrhosis. Recently, there has been an introduction of drugs called direct acting antivirals that have improved the chance for sustained viral response from around 50% to around 90%. In this talk, we introduce a new mathematical model for Hepatitis C dynamics treated with the direct acting antiviral drug, telaprevir, alongside interferon and ribavirin. We also demonstrate the sensitivity and identifiability techniques used to validate the model, as well as fit the model to data received from clinical trials.","mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4afrvdfh3tolh1plbg1c5indsk","2016-03-27 12:30:44",NULL
"3488","46","An instability in the Standard Model of Cosmology Creates the Anomalous Acceleration without Dark Energy","2016-04-11 16:00:00","2016-04-11 17:00:00","SAS 1102","Blake Temple","https://www.math.ucdavis.edu/~temple/","University of California , Davis","Irina Kogan","http://www.math.ncsu.edu/~iakogan/Talks/BlakeTempleAbstractNCSU-3-7-16.pdf",,"iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2pf0sqdgfqal6b5dhf1v39m9s4","2016-03-27 16:26:25","2016-03-30 18:53:28"
"3489","12","Optimization Program Summer School","2016-08-08 08:00:00","2016-08-08 15:00:00","NC Biotech Center  Hamner Confererence Center, RTP, NC",,,,"Gehrmann",,"Optimization Program Summer School
August 8-12, 2016
This event will be held at the &lt;a href=&quot;http://www.ncbiotech.org/about-us/conference-center&quot;&gt;Hamner Confererence Center&lt;/a&gt; in Research Triangle Park, NC.
The application deadline is June 8, 2016.

To Apply: Please click on this &lt;a href=&quot;http://www.mathprograms.org/db/programs/444&quot;&gt;link&lt;/a&gt; and submit a CV, a transcript (if you are a student), and a statement of interest. A letter of recommendation must be submitted by your advisor. Notifications of acceptance will be sent in July 2016.
The Summer School will introduce graduate students and early-career researchers in the Mathematical and Statistical Sciences to the mathematical and statistical approaches in Optimization, and their applications.

Each day will be devoted to a specific topic. Topics under consideration include: E/M &amp; M/M algorithms; statistical and mathematical inverse problems; optimization under uncertainty; convex and semi-definite optimization; robust optimization, sparse regression, and stochastic gradient descent; mixed integer, linear &amp; nonlinear optimization; and PDE-constrained optimization. Applications to be considered include: machine learning; image &amp; signal processing; and compressed sensing.

SAMSI Directorate liaison: Ilse Ipsen

Workshop Organizers:
Ilse Ipsen
Ekkehard Sachs
Hua Zhou
 

Send questions to opt@samsi.info","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mlb67mhgvf2cpvnem5o7bjmdjo","2016-03-29 11:26:01",NULL
"3490","21","The Chancellors Faculty Excellence Program Faculty Cluster on Personalized Medicine Discovery","2016-03-20 16:30:00","2016-03-20 17:30:00","SAS 2203","L. Kristin Newby",,"Professor of Medicine, Division of Cardiology Duke University Medical Center","flores",,"The MURDOCK Study and Baseline Project: Thinking Big (Data)
in the Era of Precision Medicine

Precision Medicine holds the promise of treatments that are personalized to an individual patients characteristics. Dr. Newby is one of the lead researchers for two important studies taking place right here in North Carolina that are collecting the vast data needed to inform precision medicine: The MURDOCK Study, which is gathering data and samples from over 11,000 volunteers in Cabarrus County and Kannapolis; and the 10,000 person Baseline Study, a collaboration between Duke University, Stanford University, and Verily (formerly Google Life Sciences). Dr. Newby will describe these studies and give us an insiders perspective on what she and her fellow researchers are learning from them.

The lecture will be followed by a student poster session and reception in the 2nd floor Atrium of SAS Hall.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/r48u4e47nvk03u5df067ccfme8","2016-03-30 10:38:09",NULL
"3491","38","Partition-Based Proposal Distributions for Importance Sampling - advised by Min Kang","2016-05-04 13:30:00","2016-05-04 15:00:00","SAS 3282","Raywat Tanadkithirun",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/cbln3ja9a36bfrjk5fa42hrlq8","2016-04-01 16:29:58",NULL
"3492","14","Departmental Tea and Cookies","2016-04-04 15:30:00","2016-04-04 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/a5odctu04r46hjf4d3681f6s6k","2016-04-04 10:23:37",NULL
"3493","10","Biological Optimization of Radiation Therapy Treatments","2016-04-05 16:30:00","2016-04-05 17:30:00","Daniels 218","David Papp",,"NC State",,,"Radiation therapy is one of the primary treatment options for cancer patients. During a radiotherapy treatment session the patient is irradiated with high-energy x-rays that kill both cancerous and healthy cells. To minimize the side-effects resulting from the irradiation of healthy cells, the treatment has to be personalized to the patients exact geometry; this is done using large-scale optimization models specific to the patient.

It has been an established paradigm for decades that treatment optimization is based on the physical radiation dose delivered to the patient. This leads to relatively simple, well-understood and well-calibrated models. However, the ultimate goals of treatment are defined in terms of biological endpoints (e.g. cancer cell death), and it is also well-known that the biological effects of treatments with identical physical doses can be very different.

Treatment optimization based on biological effects has the potential to increase treatment success, and reduce radiation damage to healthy tissues, compared to current clinical practice. On the other hand, the resulting optimization models are much more challenging to solve than conventional ones. The talk will focus on open problems in the area. The initial results presented are joint work with Jan Unkelbach from Massachusetts General Hospital.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n0q8t1o2uvjdcpknfn354e2um0","2016-04-04 10:37:50","2016-04-04 11:11:33"
"3494","19","Toric Varieties in Statistics","2016-04-06 16:30:00","2016-04-06 17:30:00","SAS Hall 2102","Daniel Bernstein",,,,,"In the first half of my talk, I will explain how certain statistical models can be viewed as toric varieties, and how the algebraic theory can be leveraged to develop algorithms for hypothesis testing. In the second half, I will describe some &quot;niceness&quot; properties that a toric ideal can satisfy, and their implications for statistical algorithms. Then, I will present some recent results and work in progress related to these properties for hierarchical models.  I will not assume any background beyond some basic abstract algebra, so this talk should be accessible to a broad audience including first years.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qd9gmqfnntkckh1p7sivrjbps4","2016-04-04 11:31:50",NULL
"3495","20","Switching Diffusions and Applications","2016-04-15 15:00:00","2016-04-15 16:00:00","COX 306","George Yin",,"Department of Mathematics, Wayne State University",,,"Many problems in control and optimization require the treatment of systems in which continuous dynamics and discrete events coexist, which is the focus of this talk. We present a survey of some of our recent work on such systems. In the setup, the discrete event is given by a random process with a finite state space, and the continuous component is the solution of a stochastic differential equation. Seemingly similar to diffusions, the processes have a number of salient features distinctly different from diffusion processes. After providing motivational examples arising from wireless communications, identification, finance, singular perturbed Markovian systems, manufacturing, and consensus controls, we present necessary and sufficient conditions for the existence of unique invariant measure, stability, stabilization, and numerical solutions of control and game problems.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/7h5p9tokc2i0jqvqjdb805rn2g","2016-04-12 11:39:55",NULL
"3496","46","Homological operations on Khovanov homology","2016-04-28 13:30:00","2016-04-28 14:30:00","SAS 4201","Alexander Shumakovitch",,"George Washington University","Radmila Sazdanovic",,"There are several homological operations that can be defined between even and odd Khovanov homology theories using the unified homology theory developed by Putyra. This construction works for both reduced and unreduced versions of the Khovanov homology. We discuss these homological operations, compare different versions of them, and show how they can give rise to new knot invariants with interesting properties. 
This is a joint work with Krzysztof Putyra.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fu18lav63mo8e142ddpd1p4p7c","2016-04-15 10:02:00","2016-04-19 14:05:22"
"3497","46","An introduction to the Turaev surface","2016-04-28 14:45:00","2016-04-28 15:45:00","SAS 4201","Adam Lowrance","http://faculty.vassar.edu/adlowrance/research.html","Vassar College","Radmila Sazdanovic",,"The Turaev surface is a certain oriented surface associated to each link diagram. It is closely related to Jones-type link invariants. In this talk, we will construct the Turaev surface and highlight its connections to the Jones polynomial, Khovanov homology, and other link invariants. We also discuss strategies for computing the minimum genus of the Turaev surface.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2ifvi1hgec3r90d8q5gd8oh0dg","2016-04-15 10:04:10",NULL
"3498","46","Does Khovanov homology lead to wedges of spheres?","2016-04-28 16:00:00","2016-04-28 17:00:00","SAS 4201","Jozef Przytycki","http://home.gwu.edu/~przytyck/","George Washington University","Radmila Sazdanovic",,"It has been proven in [GMS] that extreme Khovanov homology is a  reduced homology of the simplicial complex obtained from bipartite circle graph constructed from a link diagram (so called Lando graph of a link). In this talk we conjecture that this simplicial complex is always homotopy equivalent to a wedge of spheres. In particular, this homotopy type is a link invariant.  We prove the conjecture in many special cases and find it convincing to generalize conjecture for any circle graph (intersection graph of cords in a circle). As suggested by  M.Adamaszek, we prove that for a permutation graph  the conjecture hold. We demonstrate how, for any finite wedge of spheres, to find a permutation graph $G$ with $I_G$ of its homotopy type. We modify our construction to show, in particular, that for any $n$ there is a Lando graph $G$ with its independence simplicial complex, $I_G$, homotopy equivalent to $S^n\vee S^{2n-1}$. Another family of graphs, again suggested by Adamaszek, have non-nested cords on one side of the circle. We prove that for this family (and its small generalizations) the conjecture holds. We give several other examples supporting wedge of spheres conjectures, but full conjectures  are still open.
We would like to thank Michal Adamaszek, Sergei Chmutov, and Victor Reiner for helpful advice.
[GMS]  J.Gonz\alez-Meneses, P.M.G.Manch\on, M.Silvero, A geometric description of the extreme Khovanov cohomology,
e-print: arXiv:1511.05845 [math.GT]","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/aej8pn4papb09o30qa7vjmvo70","2016-04-15 10:07:10","2016-04-15 10:09:49"
"3499","15","End of year meeting and election of 2016-17 officers","2016-04-19 13:00:00","2016-04-19 14:00:00","Poe 517",,,,,,,"allewis2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/tsbc26hvptqep6a3u073h5raj4","2016-04-17 12:14:48","2016-04-17 12:16:05"
"3500","38","Bayesian methods for exploratory functional data analysis and existence theorems for solutions to nonlinear differential and difference equations - advised by Jesus Rodriguez and Subhashis Ghoshal","2016-05-06 10:00:00","2016-05-06 11:30:00","SAS 5202","Adam Suarez",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/224mqvsqhdnl684713ebvc665s","2016-04-17 19:42:10",NULL
"3501","14","NC State Mathematics Graduation Ceremony","2016-05-06 15:00:00","2016-05-06 17:00:00","SAS 2203",,,,,"http://www.math.ncsu.edu/undergrad/graduation/index.html","Graduation will be on Friday, May 6, 2016 in 2203 SAS Hall at 3:00 pm. The reception will follow the graduation ceremony.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/k9paohjo569t3bd1oqfbmv140s","2016-04-18 12:23:54","2016-04-20 12:39:26"
"3502","28","Elections and End of Year Ice Cream Social","2016-04-22 14:30:00","2016-04-22 15:30:00","SAS 2229",,,,"AWM",,"Cool down the end of the semester with ice cream and AWM. We will be voting for officers for next year.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/fs3lhs4pengmdhjectd3e2eavc","2016-04-19 10:25:00",NULL
"3503","38","Cost and benefit analysis of vaccination strategies for the HIV virus - advised by Negash Medhin","2016-05-04 09:00:00","2016-05-04 10:30:00","SAS 4201","Erin Acquesta",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/m0el6u295o7aer306uu7apfq9k","2016-04-20 13:03:40",NULL
"3504","8","Contrast improvement in Nuclear Magnetic Resonance Imagery: When Symbolic Computation meets Optimal Control Theory","2016-04-29 16:00:00","2016-04-29 17:00:00","SAS 4201","Mohab Safey El Din","http://www-polsys.lip6.fr/~safey/","Universite Pierre et Marie Curie",,,"Control theory has recently been involved in the field of nuclear magnetic resonance imagery. The goal is to control the magnetic field optimally in order to improve the contrast between two biological matters on the pictures. Geometric optimal control leads us here to analyze meromorphic vector fields depending upon physical parameters, and having their singularities defined by a determinantal variety. The involved matrix has polynomial entries with respect to both the state variables and the parameters. Taking into account the physical constraints of the problem, one needs to classify, with respect to the parameters, the number of real singularities lying in some prescribed semi-algebraic set. We develop a dedicated algorithm for real root classification of the singularities of the rank defects of a polynomial matrix, cut with a given semi-algebraic set. The algorithm works under some genericity assumptions which are easy to check. These assumptions are not so restrictive and are satisfied in the aforementioned application. Our algorithm needs to compute the critical loci of some maps, intersections with the boundary of the semi-algebraic domain, etc. In order to compute these objects, the determinantal structure is exploited through a stratification by the rank of the polynomial matrix. This speeds up the computations by a factor 100. Furthermore, our implementation is able to solve the application in medical imagery, which was out of reach of more general algorithms for real root classification. For instance, computational results show that the contrast problem where one of the matters is water is partitioned into three distinct classes.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/r0n6vms82qsvkjtj5etvdu2530","2016-04-21 14:52:10","2016-04-21 14:52:54"
"3505","21","Knots in The Triangle","2016-04-29 13:00:00","2016-05-01 17:00:00","SAS Hall",,,,"radmila","http://home.gwu.edu/~przytyck/knots/knotsinwashington42.htm",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1m4o8dr09ci6tjpftrcegbsikc","2016-04-22 10:38:51",NULL
"3506","14","John Griggs' Stepping Down Celebration","2016-04-26 14:00:00","2016-04-26 15:00:00","SAS 4104",,,,,,"John Griggs will be stepping down as Coordinator of Classroom Instruction and Assistant Department Head as of May16, 2016.  John has served in this role for 20 (!!!) years and I would like to take a moment and thank John for all these years of dedication, enthusiasm and support and for all his hard work. 

Molly Fenn will will be taking over this position next year.

A reception will be held on Tuesday April 26, 2016 2:00- 3:00 PM. Please join me in thanking John for his contributions and welcoming Molly as the new Coordinator of Classroom Instruction and Assistant Department Head.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6f8gvs2thcbdq5mlm4h2ubno4c","2016-04-25 10:13:59",NULL
"3507","38","Uncertainty Quantification for Mixed-Effects Models with Applications in Nuclear Engineering - advised by Ralph Smith","2016-06-21 12:00:00","2016-06-21 13:30:00","SAS 3282","Kathleen Schmidt",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/60ui30cifdj1bnov4q5q3mt9h4","2016-05-03 16:08:05","2016-05-03 16:11:51"
"3508","38","Vertex Operators and the Kostka-Foulkes Polynomials - advised by Naihuan Jing and Ernie Stitzinger","2016-05-18 14:30:00","2016-05-18 16:00:00","SAS 3282","Timothee Bryan",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/hpbq29kn6qj5b9mokuqrbcorhg","2016-05-03 16:10:44",NULL
"3509","38","Optimization, Modeling and Control: Applications to Klystron Design and Hepatitis C Virus Dynamics","2016-05-18 13:00:00","2016-05-18 14:30:00","SAS 4201","George Lankford",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ckj6pbla30pbcibgn98avhd1go","2016-05-04 12:07:14",NULL
"3510","38","A Robin-Robin DDM for a Stokes-Darcy Structure Interaction with a Locally Modified Mesh and Gradient Finite Element Method - advised by Zhilin Li","2016-07-25 10:00:00","2016-07-25 11:30:00","SAS 3282","Zhaohui Wang",,"NC State",,,,"mahaider","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/j0t14tfa8h9t015dbeicvd1hgs","2016-05-18 11:12:57",NULL
"3511","34","Two new contributions to coalescent theory: i. An importance sampler for a 2 loci model with recombination and ii.  The almost infinite site (AIS) model for mutations","2016-07-07 11:00:00","2016-07-07 12:00:00","Ricks 336","Jotun Hein","https://www.stats.ox.ac.uk/people/academic_staff/jotun_hein","Oxford University",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hkrjm53e2h8oq8t6tnn43b8gh4","2016-06-27 09:25:46",NULL
"3512","38","Certifying solutions of polynomial systems over Q -- Advised by Agnes Szanto and Jonathan Hauenstein","2016-08-15 10:00:00","2016-08-15 12:00:00","SAS 3282","Tula Ayyildiz Akoglu",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/5lgp9uvf20uu8sfd6v54sb0fa8","2016-07-21 13:08:47","2016-07-21 13:10:27"
"3513","1","High order numerical methods for hyperbolic equations","2017-03-02 16:00:00","2017-03-02 17:00:00","SAS 1102","Chi-Wang Shu","http://www.dam.brown.edu/people/shu/","Brown University","Zhilin Li",,"Hyperbolic equations are used extensively in applications including fluid dynamics, astrophysics, electromagnetism, semiconductor devices, and biological sciences.  High order accurate numerical methods are efficient for solving such partial differential equations, however they are difficult to design because solutions may contain discontinuities.  In this talk we will survey several types of high order numerical methods for such problems, including weighted essentially non-oscillatory (WENO) finite difference and finite volume methods, discontinuous Galerkin finite element methods, and spectral methods.  We will discuss essential ingredients, properties and relative advantages of each method, and provide comparisons among these methods.  Recent development and applications of these methods will also be discussed.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/uajjfqls5k67hvhlejuol7cs4g","2016-07-23 10:34:51","2017-01-20 15:52:40"
"3514","21","RTG Workshop on Parameter Estimation for Biological Models","2016-07-28 09:00:00","2016-07-31 12:00:00","SAS 1102",,,,"Alun Lloyd","http://rtg.math.ncsu.edu/workshop",,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/54nnmjkv1oulklr0adh39km2us","2016-07-28 07:33:41","2016-07-28 07:35:27"
"3515","6","Adaptive sparse quadrature for high-dimensional integration with Gaussian distribution: application to Bayesian inverse problems","2016-09-08 15:00:00","2016-09-08 16:00:00","SAS 4201","Peng Chen","http://users.ices.utexas.edu/~peng/","UT Austin, ICES","Alen Alexendarian",,"In this talk, we will present convergence analysis of an adaptive sparse quadrature for high/infinite-dimensional integration with respect to Gaussian distributed random variables. Under certain assumptions on the univariate quadrature and the regularity of the integrand, we will demonstrate the dimension-independent convergence property of the proposed algorithm. We apply this algorithm to infinite-dimensional Bayesian inverse problems in combination of a Hessian-based parametrization of the uncertain parameter.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/l51bugsv9rd74188ugsqeka9dg","2016-08-01 17:49:28","2016-09-01 11:58:53"
"3516","36",,"2016-08-26 15:00:00","2016-08-26 16:00:00","SAS 4201","Arvind Saibaba and Cynthia Vinzant",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/e5b7r1728ehrdcl3lsslgb3mdo","2016-08-04 11:38:51",NULL
"3517","36",,"2016-09-09 15:00:00","2016-09-09 16:00:00","SAS 4201","Ruian Ke and Ralph Smith",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/la9ssu5522g0mtvabtj2ld4a14","2016-08-04 11:39:48",NULL
"3518","36",,"2016-09-23 15:00:00","2016-09-23 16:00:00","SAS 4201","Tye Lidman and David Papp",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/e6i221fjjnrnmd4j766nphu0js","2016-08-04 11:40:29",NULL
"3519","36",,"2016-10-14 15:00:00","2016-10-14 16:00:00","SAS 4201","Patrick Combettes and Khai Nguyen",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/bqsvjql4gckktnsr563f93vlns","2016-08-04 11:41:21",NULL
"3520","36",,"2016-10-28 15:00:00","2016-10-28 16:00:00","SAS 4201","Naihuan Jing and Agnes Szanto",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/918132e28v1tt1q84til7g39vc","2016-08-04 11:42:17","2016-08-05 14:55:09"
"3521","46","Commutativity, Bundles and K-theory","2016-08-23 16:30:00","2016-08-23 17:30:00","SAS 4201","Alejandro Adem",,"University of British Columbia","Radmila Sazdanovic",,"In this talk I will describe a new cohomology theory constructed out of commuting unitary matrices. I will discuss its role in bundle theory and homotopy theory.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/00fcqqvj65247ps0vk8b74mtv0","2016-08-07 21:36:12","2016-08-22 00:08:57"
"3523","8","Computing Simple Multiple  Zeros  of Polynomial Systems","2016-10-25 13:30:00","2016-10-25 14:30:00","SAS 4201","Lihong Zhi","http://www.mmrc.iss.ac.cn/~lzhi/","Chinese Academy of Sciences",,,"Given a polynomial system $f$ with a multiple zero of simple singularity, we provide a lower bound on the minimal distance between the simple multiple zero and  other zeros of $f$. For an approximate simple multiple zero $x$  of multiplicity $k$,  we give a numerical criterion for $f$ has $k$ roots in the ball of  radius $r$ around $x$.   We  provide a symbolic-numeric algorithm  which  converges quadratically  to  the exact simple singular zero $z$ of $f$ if $\|z-x\| \leq r$.   This is ongoing joint work with Zhiwei Hao, Wenrong Jiang, Nan Li.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/t8vf4qs4sig7kee093nud6ecik","2016-08-09 12:08:54","2016-10-04 15:28:04"
"3524","8","The Geometry of Rank-One Tensor Completion","2016-09-20 13:30:00","2016-09-20 14:30:00","SAS 4201","Zvi Rosen","https://www.math.upenn.edu/~zvihr/","University of Pennsylvania",,,"Suppose a rank-one tensor is projected onto a subset of its entries. What does the image look like? This question is motivated by statistics -- given a collection of independent discrete random variables, the joint distribution is a rank one tensor. We study partial tensors whose entries are:
1) Complex -- the algebraic version,
2) Real -- a combinatorial variant of the complex case, and
3) Probabilities -- where more elaborate semi-algebraic tools come into play.
I will sketch the results for arbitrary partial tensors and diagonal partial tensors. Based on joint work with Thomas Kahle, Kaie Kubjas, and Mario Kummer.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/489av2tvpk2q2li4j2777ut8io","2016-08-10 13:16:58","2016-09-15 16:09:51"
"3525","8","Finite automata, automatic sets, and difference equations","2016-08-30 13:30:00","2016-08-30 14:30:00","SAS 4201","Michael Singer","http://www4.ncsu.edu/~singer/","NC State",,,"A finite automaton is one of the simplest models of computation. Initially introduced by McCulloch and Pitts to model neural networks, they have been used to aid in  software design as well as to characterize certain formal languages and number-theoretic properties of integers. A set of integers is said to be m-automatic if there is a finite automaton that decides if an integer is in this set given its base-m representation.  For example powers of 2 are 2-automatic but not 3-automatic. This latter result follows from a theorem of Cobham describing which sets of integers are m- and n-automatic for sufficiently distinct m and n. In recent work with Reinhard Schaefke, we gave a new proof of this result based on analytic results concerning normal forms of systems of difference equations.  In this talk, I will describe this circle of ideas.  No previous knowledge of any of these subjects will be assumed.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/75u0188nl1kqkq0f8rqd0qa2lc","2016-08-10 13:24:32",NULL
"3526","46","Positive-definite symplectic four-manifolds","2016-08-31 16:00:00","2016-08-31 17:00:00","SAS 4201","Tye Lidman","https://www.ias.edu/scholars/tye-lidman","NCSU","Radmila Sazdanovic",,"Much is still unknown about the differential topology of smooth four-manifolds.  After surveying the landscape of four-manifold topology, we will discuss the role of symplectic forms in this realm and give some new constraints on which four-manifolds admit symplectic structures.  This is related to the existence of so-called perfect Morse functions.  This is joint work with Jennifer Hom.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/t2mdlmfc3sgibj77gabk1r1f74","2016-08-10 15:11:30",NULL
"3527","3","Crystal bases and Cluster algebras","2016-08-12 10:00:00","2016-08-12 11:00:00","SAS 4201","Toshiki Nakashima",,"Sophia University, Tokyo, Japan",,,"Let g be a finite dimensional simple Lie algebra with generators {e_i, f_i, h_i} and V= V(\lambda) be an irreducible g-module, W be the Weyl group. For w \in W the
Demazure module V_w is the subspace of V generated by the extremal vector u_{w\lambda}. It is known that the Demazure module V_w admits crystal base. In this talk we will give some relations between monomial realizations of the Demazure crystals and cluster algebras on certain double Bruhat cells.","smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/doslmda29mo2mbeocvec1kvo9s","2016-08-11 09:59:53",NULL
"3528","46","Straightening out degeneracy in CR geometry: When can it be done?","2016-09-14 16:00:00","2016-09-14 17:00:00","SAS 4201","Curtis Porter",,"NC State","Irina Kogan",,"CR geometry studies boundaries of domains in C^n and their generalizations. A central role is played by the Levi form L of a CR manifold M, which measures the failure of the CR bundle to be integrable, so that when L has a nontrivial kernel of constant rank, M is foliated by complex manifolds. If the local transverse structure to this foliation still determines a CR manifold N, then we say M is CR-straightenable, and the Tanaka-Chern-Moser classification of CR hypersurfaces with nondegenerate Levi form can be applied to N. It remains to classify those M for which L is degenerate and no such straightening exists. This was accomplished in dimension 5 by Ebenfelt, Isaev-Zaitzev, and Medori-Spiro. I will discuss their results as well as my recent progress on the problem in dimension 7","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sahenodv8fgu35o8jfunlipkog","2016-08-12 10:34:46","2016-08-16 11:44:58"
"3529","46","Characterization of Grosss Calabi-Yau variations of Hodge structure type by characteristic forms","2016-09-28 16:00:00","2016-09-28 17:00:00","SAS 4201","Colleen Robles","https://www.math.duke.edu/~robles/","Duke University","Irina Kogan",,"Gross showed that to every Hermitian symmetric tube domain we may associate a canonical variation of Hodge structure (VHS) of Calabi-Yau type.  The construction is representation theoretic, not geometric, in nature, and it is an open question to realize this abstract VHS as the variation induced by a family of polarized, algebraic Calabi-Yau manifolds. In order for a geometric VHS to realize Grosss VHS it is necessary that the invariants associated to the two VHS coincide.  For example, the Hodge numbers must agree.  The later are discrete/integer invariants. Characteristic forms are differential-geometric invariants associated to VHS (introduced by Sheng and Zuo).
Remarkably, agreement of the characteristic forms is both necessary and sufficient for a geometric VHS to realize one of Grosss VHS.  That is, the characteristic forms characterize Grosss Calabi-Yau VHS.  I will explain this result, and discuss how characteristic forms have been used to study candidate geometric realizations of Grosss VHS.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/g0sj2el5rkdnf2jo0qjb5u5oco","2016-08-12 10:40:07","2016-09-08 18:10:34"
"3530","46","Geometric Mechanics and Nonlinear Dynamics in Robotic Locomotion","2016-10-26 16:00:00","2016-10-26 17:00:00","SAS 4201","Scott Kelly","http://mees.uncc.edu/directory/scott-david-kelly","UNC Charlotte","Irina Kogan",,"Locomotion in nature generally hinges on the exploitation or breaking of symmetry in a sense that can be made precise using the language of differential geometry. This talk will describe simple mathematical models for a variety of biologically inspired robotic systems that achieve self-propulsion through cyclic changes in shape, highlighting the role played by symmetry or symmetry-breaking as an enabling factor in each case. Particular attention will be given to nonlinear phenomena arising in aquatic locomotion, including localized propulsive vortex shedding, dissipation-induced recovery in the presence of viscous drag, and wake energy harvesting within arrays of hydrodynamically coupled swimmers, and links will be discussed between problems in aquatic locomotion and problems in nonholonomic mechanics.

Scott David Kelly earned a BS in Mechanical &amp; Aerospace Engineering from Cornell University and an MS and PhD in Mechanical Engineering from the California Institute of Technology. He worked as a research engineer in Biological Systems Modeling at Entelos, Inc. and as a faculty member in Mechanical Science &amp; Engineering at the University of Illinois at Urbana-Champaign, receiving a National Science Foundation CAREER Award in 2005 and a Presidential Early Career Award for Scientists and Engineers (PECASE) in 2006, before joining the department of Mechanical Engineering &amp; Engineering Science at UNC Charlotte in 2007. Professor Kellys research interests include analytical mechanics, nonlinear dynamics and control, differential geometry, robotics, and systems biology.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n1heiliu964j2ofus0nf93ojs8","2016-08-12 11:29:14","2016-10-24 11:28:26"
"3531","6","An efficient threshold dynamics method for wetting dynamics","2016-08-23 15:00:00","2016-08-23 16:00:00","SAS 4201","Xiao-Ping Wang","https://www.math.ust.hk/~mawang/","Hong Kong University of Science and Technology HKUST","Zhilin Li",,"We develop an efficient volume preserving threshold dynamics (MBO)
method for drop spreading  on rough surfaces. The method is based
on minimization of the weighted surface area functional over a
extended domain that includes the solid phase.   The method is
simple, stable with the complexity O(N log N) per time step and it is not sensitive to the inhomogeneity or roughness  of the solid boundary.   We also extend the idea to an efficient method for image segmentation.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nomno00gnf9skc8qbj09fh1e3g","2016-08-17 10:44:52","2016-08-17 12:04:36"
"3532","3","Model-Free Consistency of Graph Partitioning using Dense Graph Limits","2016-09-19 15:00:00","2016-09-19 16:00:00","SAS 4201","Peter Diao","http://peterdiao.com","SAMSI",,,"The beautiful work of Borgs, Chayes, Lovasz, Sos, Szegedy, Vesztergombi, and many others on dense graph limits has received quite a bit of attention in pure math as well as statistics and machine learning.  In this talk we will review some of the previous work on dense graph limits and then present recent work on providing a more robust mathematical framework for proving the statistical consistency of graph partitioning algorithms such as spectral clustering. A striking feature of our approach is that it is model-free, compared to the popular iid paradigm. Our results are thus broadly applicable in real-world settings, where it is notoriously difficult to obtain relevant models for network data, and observations are not independent. At the end, I will discuss implications for how mathematical foundations can be developed for other modern data analysis techniques. This is joint work with Dominique Guillot, Apoorva Khare, and Bala Rajaratnam.  Preprint available at https://arxiv.org/abs/1608.03860.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/gc3jdo02etqj2rsj68iif5onog","2016-08-17 13:52:28",NULL
"3533","22","Algebra through logarithmic glasses","2016-09-01 16:30:00","2016-09-01 17:20:00","SAS 2102","Cynthia Vinzant","http://www4.ncsu.edu/~clvinzan/","NC State",,,,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4etc3covbg0u02h10kf3v1bbd0","2016-08-18 12:28:33","2016-08-18 15:06:40"
"3534","14","Fall 2016 Math Department Reception","2016-08-18 15:30:00","2016-08-18 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/a0hpcqv1a40q1064k479g68r4c","2016-08-18 14:50:25","2016-08-18 14:52:20"
"3535","14","Fall 2016 Math Department Meeting","2016-08-18 16:00:00","2016-08-18 17:00:00","SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/fd8q6celtro282td109rfqvcfk","2016-08-18 14:51:28",NULL
"3536","22","Puzzling probabilities","2016-09-08 16:30:00","2016-09-08 17:20:00","SAS 2102","Ricky Liu","http://www4.ncsu.edu/~riliu/","NC State",,,,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/b4irrgvf4d4dbrrfminjt00gf8","2016-08-18 15:05:52","2016-08-30 13:37:59"
"3537","28","Welcome Event","2016-08-29 15:00:00","2016-08-29 16:00:00","Poe 209",,,,"AWM",,"Please join us for the first AWM event of the year. We will be doing a new ice-breaker and there will be plenty of snacks! All are welcome, not just women.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2o0krscnk5s016noed4t7jhe2g","2016-08-18 20:47:41","2016-08-23 20:58:59"
"3538","46","Topological Data Analysis: Math, Statistics, and Applications","2016-08-24 16:00:00","2016-08-24 17:00:00","SAS 4201","Brittany Terese Fasy","https://www.cs.montana.edu/brittany/","Montana State University","Radmila Sazdanovic",,"Topology studies the structure of shapes. Topological data analysis (TDA) is the study of the shape of (often large high-dimensional, and noisy) data. Often, in TDA, the data set is transformed into a concise descriptor, such as a persistence diagram or a dendogram, which can then be used to (indirectly) compare or classify data sets. In this talk, we will define a persistence diagram and confidence sets for persistence diagrams. Then, we will discuss how we can use these confidence sets to perform statistical hypothesis testing, and provide a few examples of where weve applied (or are applying) these methods.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8jkg02p1oi10v15fjnbkul5e98","2016-08-18 23:53:56","2016-08-19 10:06:57"
"3539","1","PDE models of controlled growth","2016-11-10 16:00:00","2016-11-10 17:00:00","SAS 1102","Alberto Bressan","https://www.math.psu.edu/bressan/","Pennsylvania State University","Khai Nguyen",,"Living tissues, such as stems, leaves and flowers in plants and bones in animals, grow into a great variety of shapes. In some cases, Nature has found ways to control this growth with remarkable accuracy. In this talk I shall discuss some free boundary problems modeling controlled growth, namely

(I) Growth of 1-dimensional curves in R^3 (plant stems), where stabilization in the vertical direction is achieved by a feedback response to gravity. The presence of obstacles (rocks, branches of other plants) yields additional unilateral constraints. In this case, the evolution can be modeled as a differential inclusion in an infinite dimensional space.

(II) Growth of 2- or 3-dimensional domains, controlled by the  concentration of a morphogen, coupled with the minimization of an elastic deformation energy.

Some very recent existence, uniqueness, and stability results will be presented, together with numerical simulations.   Several research directions will be discussed.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/6l2sp3b80kgbnfoevg705tfmcs","2016-08-19 13:30:55","2016-11-07 11:24:25"
"3540","19","Welcome!","2016-08-24 16:30:00","2016-08-24 17:30:00","SAS Hall 2102",,,,,,"Come to the first graduate student algebra and combinatorics seminar. This meeting will set us up a semester of great talks (who knows, maybe by you???).

See you there!","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nphj68c67cf2stbeqci26km8ec","2016-08-22 10:28:04",NULL
"3542","1","One hundred years of Hellys theorem","2016-11-17 16:00:00","2016-11-17 17:00:00","SAS 1102","Jesus De Loera","https://www.math.ucdavis.edu/~deloera/","University of California, Davis","Agnes Szanto",,"Convex geometry has experienced a renaissance due to applications in optimization algorithms and machine learning. The classical theorem of Edouard Helly (1913) is a masterpiece of convex geometry. It states that if a family of convex sets in R^n has the property that every n+1 of the sets have a nonempty intersection, then all the convex sets must intersect. Hellys theorem has since found applications in many domains, recently in  convex discrete optimization and in computer algebra via sampling style algorithms.

My lecture will begin by explaining the basics of convex geometry (e.g., what is a convex set?) and will proceed with a selection of lovely applications of Hellys theorem. The last part of the talk will deal with some surprising combinatorial generalizations.  My favorite one is our new version of Hellys theorem where the intersection(s) count lattice points. This side of the story originated in the 1970s  work of Doignon, Bell and Scarf (arising in economic theory) and was followed by joint work with Aliev and Louveaux in the last two years. I promise I will mention the history of the subject and provide some open questions. Graduate students are guaranteed to understand a big portion of this talk.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/pn1k5k10sdns3li9q2blo0vmv0","2016-08-22 12:54:53","2016-11-14 09:28:18"
"3543","8","Random Monomial Ideals","2016-11-16 15:00:00","2016-11-16 16:00:00","SAS 2102","Jesus De Loera","https://www.math.ucdavis.edu/~deloera/","University of California, Davis",,,"Monomial ideals play a key role in computational commutative algebra, most notably as Grobner degenerations of general ideals,  and they give a strong link to algebraic combinatorics e.g., through Stanley-Reisner ideals of simplicial complexes. At the same time, randomness and stochasticity has played a a key role in algebra. We were inspired  by the study of random graphs (Erdos Renyi) and simplicial complexes (Linial-Meshulam, Kahle, etc) to develop a theory of  random monomial ideals. We proved several theorems about the probability distributions, expectations and thresholds for events of monomial ideals with given Hilbert function, Krull dimension, first graded Betti numbers, and present experimentally-backed conjectures about the regularity, depth, Cohen-Macaulayness, and the probability of some well-known invariants. New results are joint work with S. Petrovic, D. Stasi, L. Silverstein, D. Wilburne.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5er5a2jtklrkkej7nm7eueh0mo","2016-08-22 13:05:50","2016-11-08 13:19:38"
"3544","46","Analytic torsion, the eta invariant, and closed differential forms on spaces of metrics","2016-10-12 16:00:00","2016-10-12 17:00:00","SAS 4201","Phil Andreae","https://sites.google.com/site/phillipandreae/","Meredith College","Andrew Cooper",,"The first part of the talk will be an introduction to Ray-Singer analytic torsion, a topological invariant constructed from Laplace eigenvalue data on a compact manifold. I will briefly introduce the Hodge Laplacian on differential forms, its spectral theory, and analytic torsion, which has a surprising connection with torsion in integer cohomology groups!

In the second part of the talk, I will discuss recent work that interprets analytic torsion as a regularized integral of a closed differential form on the space of Riemannian metrics, or more generally on a space of metrics on a vector bundle. This interpretation, along with a Stokes theorem argument, explains the dependence of torsion on the metric used to define it. This idea also applies to the eta invariant and to a novel generalization that I call &quot;multi-torsion,&quot; which is defined for certain manifolds with local product structure.","aacoope2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/d4qdv39luleuodopkcu8153f1s","2016-08-23 11:28:01","2016-09-15 15:24:28"
"3545","28","Weekly Brown Bag Lunch","2016-08-31 12:00:00","2016-08-31 13:00:00","SAS 4104",,,,"AWM",,"Please join us for the first weekly lunch of the year. You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/cvr8i98sasl10n8v6vbf42blr0","2016-08-23 21:03:12",NULL
"3546","23","Postdoctoral positions: what are they and how to apply for them","2016-09-02 15:00:00","2016-09-02 16:00:00","SAS 4201","Postdocs and Faculty panel",,,"Pierre Gremaud",,"The event is targeted at graduate students who are contemplating a postdoctoral position after graduation. A panel of current postdocs and faculty will discuss their own experience and to look for postdoctoral positions. 

We will also cover the different types of postdoctoral positions and how to apply and interview for them.

Organized in collaboration with the SIAM student chapter.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/cbcqsoh0crf0rcei84rsbnf55o","2016-08-26 08:30:29","2016-08-26 08:31:17"
"3547","23","Applying for graduate fellowships","2016-09-16 15:00:00","2016-09-16 16:00:00","SAS 4201","Seth Sullivant",,"Mathematics, NC State","Pierre Gremaud",,"Ill discuss how to go about applying for graduate research fellowships. The focus will be on the National Science Foundation Graduate Research Fellowship but the basic principles apply to many other fellowships as well.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/e56j2s1gjk7urmljan3vo12gu4","2016-08-26 08:54:10",NULL
"3549","38","Classification of 5-dimensional complex nilpotent Leibniz algebras -advised by Ernie Stitzinger and Kailash Misra","2016-09-22 10:00:00","2016-09-22 12:00:00","SAS 3282","Ismail Demir",,,,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/4nlvmbhtqh8fgc0s39r319afgc","2016-08-26 09:36:31","2016-08-26 09:38:33"
"3550","19","What is...","2016-08-31 16:30:00","2016-08-31 17:30:00","SAS Hall 2102","Group",,,,,"We have a group of graduate students giving quick (~5 minutes) introductions into some of the mathematics they use in research. Well be talking about...Polytopes, symbolic computation, cluster algebras, Lie algebras, tropical geometry, varieties, projective space, and spectrahedra!","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6t0u548thku7rtd1a5om2m8h9g","2016-08-26 16:57:08","2016-08-28 11:54:20"
"3551","19","What is...Continued!","2016-09-07 16:30:00","2016-09-07 17:30:00","SAS Hall 2102","Group",,,,,"We will continue our What is...talks this Wednesday. Come join us for short (5-10 minute) introductions to cluster algebras, symbolic computations and tropical geometry.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/efvf1l607i6g7bbduhu11etju8","2016-08-26 17:00:33","2016-09-06 11:35:49"
"3552","19","The canonical join complex","2016-09-14 16:30:00","2016-09-14 17:30:00","SAS Hall 2102","Emily Barnard",,,,,"I will discuss a certain minimal factorization of the elements in a finite lattice called the canonical join representation and the related canonical join complex. A simplicial complex is flag when its minimal non-faces have size two. We will characterize the lattices whose canonical join complex is flag. If time permits, we will discuss some examples of canonical join complexes that have nice topology.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/q6t9iqbq0di6k1usqdskoomi74","2016-08-26 17:02:41","2016-09-14 08:01:05"
"3553","19","Polytopes Associated to Group-Based Phylogenetic Models","2016-10-19 16:30:00","2016-10-19 17:30:00","SAS Hall 2102","Jane Coons",,,,,"We can learn about models of evolution by studying certain polytopes that can be obtained from them. I will discuss a few such models and how to build their associated polytopes. Then, I will prove some interesting combinatorial properties of these polytopes. This talk will be accessible to all graduate students.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/kf7edqpl49plv3j43rgjr67kes","2016-08-26 17:03:44","2016-10-17 14:13:30"
"3554","19","Folding cluster algebras","2016-11-02 16:30:00","2016-11-02 17:30:00","SAS Hall 2102","Shira Viel",,,,,"Ill begin with a very brief definition of cluster algebras (similar, but shorter, than my &quot;What is...&quot; talk last month), then introduce the notion of folding and discuss how it can be used to extend various results.","spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/tlqs5tv8no11m804f9on4vf9cc","2016-08-26 17:04:46","2016-11-02 14:19:49"
"3555","19","Resultants over commutative idempotent semirings","2016-11-09 16:30:00","2016-11-09 17:30:00","SAS Hall 2102","Georgy Scholten",,,,,"The resultant plays a crucial role in (computational) algebra and algebraic geometry. One property of the resultant is that it is equal to the determinant of the Sylvester matrix. In 2008, Odagiri proved that a similar property holds over the tropical semiring if one replaces subtraction with addition. The tropical semiring belongs to a large family of algebraic structures called commutative idempotent semiring. I will talk about how the same property (with subtraction replaced with addition) holds over an arbitrary commutative idempotent semiring.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6d6qmnpaeiijjglo4j0avdej8k","2016-08-26 17:06:23","2016-11-08 10:14:19"
"3557","14","Departmental Tea and Cookies","2016-08-31 14:30:00","2016-08-31 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/af1h9p4v9llkaa3k64tp6sr624","2016-08-29 15:03:42","2016-08-30 09:57:02"
"3558","14","Departmental Tea and Cookies","2016-09-07 14:30:00","2016-09-07 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/h1c1lhj2vih8pqin9adqjqnapo","2016-08-30 11:23:27",NULL
"3559","14","Departmental Tea and Cookies","2016-09-14 14:30:00","2016-09-14 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/cjngfr8rqfp94ojtu3l1dhdr28","2016-08-30 11:23:59",NULL
"3560","4","Compactness estimate for some nonlinear PDEs","2016-09-28 15:00:00","2016-09-28 16:00:00","SAS 4201","Khai Nguyen",,"NC State Mathematics","M. Shearer",,"This talk will be devoted to a fundamental question on the com-
pactness of sets of solutions. The key concept in this study is the Kolmogorov
epsilon-entropy which is the logarithm of the minimum number of elements in
an epsilon-covering of a given (totally bounded) set. I will use this concept to
provide a sharp estimate on minimum number of bits needed to represent a en-
tropy solution of general system of hyperbolic conservation laws and a viscosity
solution of Hamilton-Jacobi equations with accuracy epsilon.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qcsjoep6d6o3batt4di9ogl81c","2016-08-30 11:46:02","2016-09-22 14:11:14"
"3561","22","All horses are black","2016-09-15 16:30:00","2016-09-15 17:20:00","SAS 2102","Irina Kogan","http://www4.ncsu.edu/~iakogan/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2016/091516.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3980u9icqkudnm4p8vkp4fo8r4","2016-08-30 13:40:25","2016-09-13 11:44:46"
"3563","28","Women in Teaching Panel","2016-09-15 15:00:00","2016-09-15 16:00:00","Poe 214",,,,,,"Please join AWM for an afternoon of snacks and discussion about the challenges and experiences of female mathematics instructors. We will have experienced faculty and graduate student panelists, so come prepared with questions!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/mafd6acdhkkhbp6brqleu1dr7s","2016-08-31 10:10:29","2016-08-31 10:11:23"
"3564","6","Advanced Eigenvalue Solvers for Deterministic Radiation Transport","2016-12-06 15:00:00","2016-12-06 15:50:00","SAS 4201","Steven Hamilton",,"ORNL","Tim Kelley",,"Efficient solution of the k-eigenvalue form of the radiation transport equation is crucial to the design and analysis of nuclear reactors.  In many cases, the solution of the transport equation is the most computationally demanding component of the reactor analysis.  Improved methods can therefore have a significant impact on the reactor design cycle.  Power iteration has long dominated the solution of the k-eigenvalue problem, often used in conjunction with nonlinear acceleration techniques that are subject to instabilities.  In this talk, we discuss recent work applying advanced eigenvalue solvers such as the generalized Davidson method to a variety of deterministic transport solvers.  Both algebraic and physics-based preconditioning strategies will be discussed.  The computational efficiency of these methods typically far exceeds that of traditional approaches, with performance often comparable to nonlinear acceleration methods without the associated instabilities.

Dr Hamilton is a student of Michele Benzi, making him Carl Meyers academic grandson.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/b39sl8a2cp600895s4plh5rl74","2016-08-31 10:49:00","2016-11-28 15:48:17"
"3565","3","Baxter posets","2016-11-21 15:00:00","2016-11-21 16:00:00","SAS 4201","Emily Meehan","https://emeehan.wordpress.ncsu.edu/","NC State",,,"In this talk, we define a family of combinatorial objects, which we call Baxter posets. We prove that the Baxter numbers count Baxter posets by demonstrating that Baxter posets are the adjacency posets of diagonal rectangulations. Several known families of Baxter objects are closely related to Catalan combinatorics, and we motivate the definition of Baxter posets by summarizing some of these relationships. Given a diagonal rectangulation, we will describe the cover relations in the associated Baxter poset. We will also describe a method for obtaining the Baxter permutation associated to a Baxter poset.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/a0rht31q9hpmqrupn9c3t5s9k0","2016-08-31 13:31:54","2016-09-27 13:01:24"
"3566","15","TBA","2016-09-08 13:30:00","2016-09-08 14:30:00","Poe 532","Peng Chen","http://users.ices.utexas.edu/~peng/","UT Austin, ICES",,,,"jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/0iiqt1nuoktnkm5cn7bgldlj0o","2016-08-31 19:42:04","2016-09-01 10:48:20"
"3567","15","Randomized methods in linear algebra with applications to uncertainty quantification","2016-09-14 16:30:00","2016-09-14 17:30:00","SAS 1108","Alen Alexanderian","http://www4.ncsu.edu/~aalexan3/","NC State",,,"Randomized linear algebra is a research area that uses randomization as a computational approach to develop efficient algorithms for large-scale linear algebra problems.  In this talk I will discuss randomized methods for computing Singular Value Decomposition (SVD) of matrices, as well as randomized methods for computing trace and determinant of high-dimensional matrices with rapidly decaying eigenvalues.  Such matrices are common in scientific computing applications.  In addition to some simple illustrations of the randomized methods for test matrices, I will discuss some applications of these methods to problems arising in uncertainty quantification. In particular, we will consider Bayesian linear inverse problems and discuss application of randomized methods for efficient solution methods for such problems. We will also use randomized methods for computation of the log-determinant of the posterior covariance operator, which is an important uncertainty quantification measure in context of Bayesian optimal design of experiments.","jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/d63fhstvvm3ic53oq4ld9atkms","2016-08-31 19:47:54","2016-09-13 16:08:53"
"3568","4","Stability issues in fluids in curved geometries","2016-10-12 15:00:00","2016-10-12 16:00:00","SAS 4201","Jeremy Marzuola",,"UNC Mathematics Department","Michael Shearer",,"In an appendix to a recent paper by Michael Taylor, he and I explored various questions related to stability of striated patterns for fluids on rotating spheres. In addition, with Roberto Camassa, Reed Ogrosky and Nathan Vaughn, we recently explored some periodic wave trains stemming from a long wave model for viscous fluid flow along the interior of a cylinder. I will discuss these results and some open problems related to these studies. In particular, I will discuss ways in which the geometry effect the existence and stability questions at hand.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5ptdg91sivgc4dn583j9mugsb4","2016-09-01 15:28:22","2016-10-10 11:47:59"
"3569","4","The entry-exit function and geometric singular perturbation theory","2016-10-19 15:00:00","2016-10-19 16:00:00","SAS 4201","Stephen Schecter",,"NC State Mathematics","Michael Shearer",,"Motivated by the problem of finding periodic traveling waves in a diffusive predator-prey model, I will revisit the classical problem $\dot x = \epsilon$, $\dot z = h(x,z)z$, with $h(x,0)&lt;0$ for $x&lt;0$, $h(x,0)&gt;0$ for $x&gt;0$, and $\epsilon&gt;0$ small.  This ODE admits solutions that start near the negative $x$-axis, rapidly approach it, drift along it, and eventually rapidly leave it.  The relation between the limiting attraction and repulsion points is given by an integral formula.  For $h(x,z)z$ replaced by $h(x,z)z^2$, I will explain this phenomenon using geometric singular perturbation theory (joint work with Peter De Maesschalck).  It turns out that the linear case can be reduced to the quadratic case.  I will also discuss an even more recent approach to the entry-exit function, due to Ting-Hao Hsu, that uses the exchange lemma of GSPT and extra variables.  Along the way I will give background about geometric singular perturbation theory, loss of normal hyperbolicity, and the exchange lemma.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ic6r1dlb3sml651fn88j6ikj7g","2016-09-01 15:30:08","2016-10-13 15:54:20"
"3570","8","Complexity of Triangular Representations of Algebraic Sets","2016-10-11 13:30:00","2016-10-11 14:30:00","SAS 4201","Eli Amzallag",,"The Graduate Center, CUNY",,,"A long-standing problem in polynomial computation has been how to efficiently specify a representation of a given algebraic set or of its corresponding ideal without losing any important information about it.  Agnes Szanto presented an algorithm that produces a representation of the radical of a given ideal by unmixed triangular sets, which generalize Ritt-Wu characteristic sets.  Szanto provided an asymptotic upper bound for the degrees of the polynomials occurring in the computation.  The degrees of these polynomials in their leading variables were bounded effectively, but for the non-leading variables, only a big-O bound was given.  In this talk, we will first outline Szantos algorithm and then explain how we obtained explicit bounds for these degrees, as well as the number of components in the output.  Since the applications are similar, we will also demonstrate how the degree bounds are much lower than even low estimates of ones for computing the Groebner basis of the radical of the given ideal.  This is joint work with Gleb Pogudin, Mengxiao Sun, and Ngoc Thieu Vo.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6126e577reho2df256ike2a9t8","2016-09-02 14:43:36","2016-10-06 17:21:05"
"3571","8","Do Sums of Squares Dream of Free Resolutions?","2016-09-13 13:30:00","2016-09-13 14:30:00","SAS 4201","Greg Blekherman","https://sites.google.com/site/grrigg/","Georgia Tech",,,"A polynomial with real coefficients is nonnegative if it takes only nonnegative values. For example, any sum of squares of polynomials is obviously nonnegative. The study of the relationship between nonnegative polynomials and sums of squares is a classical area in real algebraic geometry. I will explain how this topic is inextricably linked to classical topics in algebraic geometry and commutative algebra, such as properties of the minimal free resolution, and discuss a specific example of square-free monomial ideals, which corresponds to matrix completion problems.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/eoittj3o9kk2ol96hv78emp0t0","2016-09-03 09:51:51","2016-09-08 09:54:57"
"3572","28","Weekly Brown Bag Lunch","2016-09-07 12:00:00","2016-09-07 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/i5bpb581be14tno4tebmrn6o6g","2016-09-06 12:36:09",NULL
"3573","28","Weekly Brown Bag Lunch","2016-09-14 12:00:00","2016-09-14 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/gji7kib2ao0vhrk6opdotmd29k","2016-09-06 12:37:15",NULL
"3574","28","Weekly Brown Bag Lunch","2016-09-21 12:00:00","2016-09-21 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/o058bmi07kh7mt8knlvrmq7ep8","2016-09-06 12:38:19",NULL
"3575","28","Weekly Brown Bag Lunch","2016-09-28 12:00:00","2016-09-28 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/v52eu3kdq5i2ipnrtaecc0dg80","2016-09-06 12:39:12",NULL
"3577","28","Weekly Brown Bag Lunch","2016-10-12 12:00:00","2016-10-12 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/03egajg3espkcgasvdomvl9mug","2016-09-06 12:50:01",NULL
"3578","28","Weekly Brown Bag Lunch","2016-10-19 12:00:00","2016-10-19 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/vkj8gonaa72ert9tub1tpr9f0s","2016-09-06 12:50:48",NULL
"3579","28","Weekly Brown Bag Lunch","2016-10-26 12:00:00","2016-10-26 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/of7imfpjviaml9i77g12n82qk4","2016-09-06 12:51:32",NULL
"3580","28","Weekly Brown Bag Lunch","2016-11-02 12:00:00","2016-11-02 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/apt54maukcagpp2f2bhno8o3uc","2016-09-06 12:52:21",NULL
"3581","28","Weekly Brown Bag Lunch","2016-11-09 12:00:00","2016-11-09 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/asu265aubpb7iodk454iinqdqs","2016-09-06 12:54:20",NULL
"3582","28","Weekly Brown Bag Lunch","2016-11-16 12:00:00","2016-11-16 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/i0a84fbne0qs0sfkd40d2mm1bo","2016-09-06 12:55:37",NULL
"3583","28","Weekly Brown Bag Lunch","2016-11-30 12:00:00","2016-11-30 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/70rtsgpt1phojamo9c37ojhm4k","2016-09-06 12:56:24",NULL
"3584","3","Oriented Flip Graphs and Noncrossing Tree Partitions","2016-10-10 15:00:00","2016-10-10 16:00:00","SAS 4201","Alexander Garver","http://www.math.umn.edu/~garv0102/","University of Minnesota",,,"Given a tree embedded in a disk, we define two lattices - the oriented flip graph of noncrossing arcs and the lattice of noncrossing tree partitions. When the interior vertices of the tree have degree 3, the oriented flip graph is equivalent to the oriented exchange graph of a type A cluster algebra. These lattices are also closely related to the representation theory of a finite dimensional algebra associated to the tree. I will explain the connection between these two lattices, why they have nice lattice structures, and how we use noncrossing tree partitions to obtain a simple characterization of c-matrices of type A cluster algebras. This is joint work with Thomas McConville.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n7n5oq5ehrou4jgsuaftqs0te8","2016-09-06 13:06:07","2016-10-04 07:09:17"
"3585","3","Hecke algebras and von Neumann algebras","2016-09-26 15:00:00","2016-09-26 16:00:00","SAS 4201","Hisashi Aoi",,"Ritsumeikan University, Japan",,,"My research field is the operator algebras, especially, von Neumann algebras which act on Hilbert spaces. One of the basic examples of von Neumann algebras comes from a group action on a measured space. I am interested in the von Neumann algebra which is determined by the orbit of a group action. My recent works are deeply related to the Hecke algebras which come from the pairs of groups. In my talk, I will explain the relations between them.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fc2s57k4atev3lslmbt5lmtug0","2016-09-06 15:27:53",NULL
"3587","23","GIST teaching panel","2016-11-04 15:00:00","2016-11-04 16:00:00","SAS 4201","Faculty panel",,,"Pierre Gremaud",,"A faculty panel will discuss teaching issues at different types of institutions.

Participants will include:

Cammey Cole Manning, Head, Dept. of Mathematics, Meredith College
Brittany Hansen, Campbell University
Peter Harries, Senior Associate Dean, Graduate School, NC State","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/28tuvsu4082tpijncajag6j964","2016-09-09 09:45:40","2016-09-09 10:22:22"
"3588","10","A Queueing Model for Internal Wards","2016-09-13 16:30:00","2016-09-13 17:30:00","Daniels 218","Jing Dong","http://users.iems.northwestern.edu/~jdong/index.htm","Northwestern University",,,"Hospital managements are increasingly searching for new strategies to improve patient-flow dynamics without increasing their resources, in an effort to reduce patients waiting times and mitigate periodical overloads.
 
Accordingly, many hospitals are experimenting with new patient-flow policies which are partly based on well-known queueing models. However, hospital queues have unique features, which are not captured by standard queueing assumptions, necessitating the development of specialized models. In this work, we propose a queueing model that takes into account the most salient features of queues associated with large Internal Wards (IWs). We characterize the maximum long-run workload that the IW can handle, and introduce a deterministic (fluid) approximation for the non-stationary dynamics. The fluid model is shown to have a unique periodic equilibrium, so that long-run performance analysis can be carried out by simply considering that equilibrium. Consequently, evaluating the effects of policy changes on systems performance, and optimizing long-run operating costs, are facilitated considerably.
 
 
Bio: Jing Dong is an Assistant Professor in the Industrial Engineering and Management Sciences Department at Northwestern University. Her primary research interests are stochastic simulation and stochastic modeling with applications in service operations management. She received her Ph.D. in Operations Research from Columbia University in 2014 and her B.S. in Actuarial Science from University of Hong Kong in 2009.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/simt77p10q3s7ca8urqrctmvcc","2016-09-09 09:52:15",NULL
"3590","15","Active Subspace Techniques for Physical, Biological and Financial Models","2016-10-26 17:00:00","2016-10-26 18:00:00","SAS 1216","Ralph Smith","http://www4.ncsu.edu/~rsmith/","NC State",,,"Many physical, biological and financial models contain parameters, initial conditions, or boundary conditions that are not identifiable in the sense that they are not uniquely determined by data. Whereas sensitivity analysis can rank the influence of parameters in many cases, it is generally not effective if parameters are linearly or nonlinear related. In this presentation, we will discuss the construction and use of active subspace techniques to determine subspaces of identifiable or influential parameters. For linear models, this can be achieved using QR or singular value decompositions (SVD), with previously discussed randomized algorithms employed for large input dimensions. For nonlinear models, one typically employs gradients or gradient approximations in combination with QR or SVD techniques. We will illustrate the construction of active subspaces and their use for model calibration through elementary algebraic, ODE and PDE examples. One goal is to illustrate the relevance of active subspace techniques for all graduate students investigating physical, biological, or financial models.","jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/dedkhsnojrsvkq0k6l2neertcg","2016-09-13 11:39:00","2016-10-19 12:31:47"
"3591","15","Functional approximation and dimensionality","2016-11-09 16:30:00","2016-11-09 17:30:00","SAS 1108","Pierre Gremaud","http://www4.ncsu.edu/~gremaud/","NC State",,,"In this talk, I will discuss both classical and recent results regarding the approximation of functions by simple models such as piecewise constant or any even constant(!) approximations. The emphasis will be on high dimensional problems, i.e., functions of &quot;many&quot; parameters or variables. In particular, we will consider in what way dimensionality, while usually a curse,  may also in some limited cases be a blessing.","jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/59v8ocaamcorthr2rq984pkbgg","2016-09-13 11:40:39","2016-11-09 13:47:59"
"3592","15","A Mathematicians Guide to Working with Engineers","2016-12-06 11:30:00","2016-12-06 12:30:00","SAS 4201","Steven Hamilton","https://www.ornl.gov/staff-profile/steven-p-hamilton","Oak Ridge National Lab","Tim Kelley",,"Problems in computational science often require interdisciplinary collaboration.  Combining the expertise of researchers from varied backgrounds offers the possibility of contributing to significant scientific advancements, but differences in the vocabulary, skills, and cultures of different fields can make these collaboration efforts extremely challenging.  In this talk, I will discuss strategies for working on interdisciplinary teams that can contribute to the success (or failure) of a project.  In particular, I will discuss some common pitfalls that I have seen mathematicians fall into when working with engineers and domain scientists.  I will highlight some recent successes at Oak Ridge National Laboratory, particularly involving modeling and simulation of nuclear reactors through the Consortium for Advanced Simulation of LWRs (CASL).

Dr Hamilton is a student of Michele Benzi, making him Carl Meyers academic grandson.","ctk","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/tmnvipsitfncndn3huhr2ebjlg","2016-09-13 11:42:43","2016-11-28 15:47:34"
"3593","19","Convexity in Neural Codes","2016-09-21 16:30:00","2016-09-21 17:30:00","SAS Hall 2102","Zev Woodstock",,,,,"How does the brain encode spatial structure? One way is through hippocampal neurons called place cells, which become associated to convex regions of space known as their receptive fields: each place cell fires at a high rate precisely when the animal is in the receptive field. The firing patterns of multiple place cells form what is known as a convex neural code. How can we tell when a neural code is convex? This remains an open question, but various topological and algebraic approaches have recently provided partial results. We will discuss a brief review of the neuroscience which gives rise to this problem, and focus on topological results pertaining to the neural convexity problem. I will present our counterexample to a conjecture in the field.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/u7fp7f6gkocoh1tq9401j420ck","2016-09-13 16:51:10","2016-09-14 08:18:14"
"3594","19","Combinatorics and Algebraic Geometry of Low Rank Matrix Completion","2016-09-28 16:30:00","2016-09-28 17:30:00","SAS Hall 2102","Daniel Berstein",,,,,"In many applications, one has a dataset expressed as a matrix where only some of the entries are known. The low rank matrix completion problem is to solve for these missing entries given that the matrix has some low rank r. I will explain how this problem can be viewed from an algebraic geometry perspective and discuss some combinatorics problems that ensue.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mrlrvmdjmv7ukei4uo7bhebuno","2016-09-13 16:52:19","2016-09-21 20:35:51"
"3595","22","Uncertainty quantification for physical and biological models","2016-09-22 16:30:00","2016-09-22 17:20:00","SAS 2102","Ralph Smith","http://www4.ncsu.edu/~rsmith/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2016/092216.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1jfgnphgvflvjk275jvm3o8mdk","2016-09-14 23:32:46","2016-09-14 23:35:24"
"3596","4","Tailoring tails in Taylor dispersion: How boundaries shape chemical delivery in microfluidics","2016-10-26 15:00:00","2016-10-26 16:00:00","SAS 4201","Daniel M. Harris",,"UNC Mathematics Department","Michael Shearer",,"We present the results of an investigation of the dispersion of a passive scalar in laminar shear flow through rectangular and elliptical channels.  We show through Monte Carlo simulations, asymptotic analysis, and laboratory experiments that the cross-sectional aspect ratio of the channel sets the longitudinal asymmetry of the resulting tracer distribution at long times.  Thin channels (aspect ratio &lt;&lt; 1) generate distributions with sharp fronts and tapering tails, whereas thick channels (aspect ratio ~ 1) produce the opposite effect.  In addition, our analysis allows us to define a golden aspect ratio which separates thin from thick channels, the value of which is remarkably similar for both the rectangular ducts and the elliptical pipes.  Our findings could potentially be useful in a number of microfluidic applications, some of which will be discussed.  

This work is joint with Manuchehr Aminian, Francesca Bernardi, Roberto Camassa, and Rich McLaughlin of the UNC Joint Fluids Lab.","shearer","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/c4hb02mnmi8lkjgvihgrmr3a98","2016-09-15 09:18:56","2016-10-12 10:38:53"
"3597","46","Straightening out degeneracy in CR geometry: When can it be done? (Part II)","2016-09-21 16:00:00","2016-09-21 17:00:00","SAS 4201","Curtis Porter",,"NCSU","Irina Kogan",,"CR geometry studies boundaries of domains in C^n and their generalizations. A central role is played by the Levi form L of a CR manifold M, which measures the failure of the CR bundle to be integrable, so that when L has a nontrivial kernel of constant rank, M is foliated by complex manifolds. If the local transverse structure to this foliation still determines a CR manifold N, then we say M is CR-straightenable, and the Tanaka-Chern-Moser classification of CR hypersurfaces with nondegenerate Levi form can be applied to N. It remains to classify those M for which L is degenerate and no such straightening exists. This was accomplished in dimension 5 by Ebenfelt, Isaev-Zaitzev, and Medori-Spiro. I will discuss their results as well as my recent progress on the problem in dimension 7","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1pn9uu258jjrch0bf06jkpod5s","2016-09-15 10:59:22","2016-09-15 11:09:28"
"3598","26","Sensitivity Analysis for a Quantum Informed Ferroelectric Energy Model","2016-09-19 16:00:00","2016-09-19 17:00:00","SAS 4201","Lider Leon",,"NC State Mathematics Graduate Student",,,"We perform global sensitivity analysis for parameters in a continuum energy model for ferroelectric materials, which is informed by density functional theory (DFT). Specifically, we use global sensitivity analysis to rank the sensitivity of phenomenological parameters governing the Landau and electrostriction energy for single-domain ferroelectric lead titanate. These techniques include Pearson correlations constructed directly from input and output relations, Sobol sensitivity indices, and Morris indices.","kdcolem2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1rrj4gjsgm79eqvoit1g831v18","2016-09-16 15:01:59",NULL
"3599","14","Departmental Tea and Cookies","2016-09-21 14:30:00","2016-09-21 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/832e9nmhtokt0pf5i8o2dve2ms","2016-09-19 11:58:24",NULL
"3600","14","Departmental Tea and Cookies","2016-10-12 14:30:00","2016-10-12 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/m152f98qcrlc2spveire4ka2io","2016-09-19 11:59:08",NULL
"3601","14","Departmental Tea and Cookies","2016-10-19 14:30:00","2016-10-19 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/p6reg2v9fdal0g2ehpbc7kvv6g","2016-09-19 11:59:56",NULL
"3602","14","Departmental Tea and Cookies","2016-10-26 14:30:00","2016-10-26 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ch1oinjoqmmho2npqudpr07nqc","2016-09-19 12:00:30",NULL
"3603","4","Sharp asymptotics for KPP fronts","2016-11-16 15:00:00","2016-11-16 16:00:00","SAS 4201","James Nolen","http://fds.duke.edu/db/aas/math/faculty/nolen","Duke University ","Lorena Bociu",,"Ill describe the asymptotic behavior of solutions to a KPP-Fisher type reaction-diffusion equation. This PDE is a simple model for biological invasion. One can also interpret the solution to the PDE in terms of a branching Brownian motion. It is well-known that solutions to the Cauchy problem may behave asymptotically like a traveling wave. On the other hand, for certain initial data (e.g. compactly supported), M. Bramson used probabilistic techniques to prove that the solution to the Cauchy problem may lag behind the traveling wave by an amount that grows logarithmically in time.  We have developed a PDE argument to describe very precisely the universal behavior of the solution and convergence to the wave at a sharp algebraic rate in the large time limit. Both the logarithmic delay and the algebraic convergence to the wave are different from what is known about other reaction-diffusion equations (with bistable non-linearity, for example). Our analysis is based on a matched asymptotic expansion to construct an approximate solution. The technique also works in more general settings, where the coefficients are periodic, for example. This is joint work with Francois Hamel, Jean-Michel Roquejoffre, and Lenya Ryzhik.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/temcvjbenas91vnihl5eu2ru04","2016-09-19 14:00:11","2016-11-10 17:14:29"
"3604","46","Geometric theory of garden hose instability","2016-11-09 16:00:00","2016-11-09 17:00:00","SAS 4201","Vakhtang Putkaradze","https://sites.ualberta.ca/~putkarad/","University of Alberta","Irina Kogan",,"We derive a fully three-dimensional, geometrically exact theory for flexible tubes conveying fluid. The theory also incorporates the change of the cross-section available to the fluid motion during the dynamics, sometimes called collapsible tubes. Our approach is based on the symmetry-reduced, exact geometric description for elastic rods, coupled with the fluid transport and subject to the volume conservation constraint for the fluid. Using these methods, we derive the fully three dimensional equations of motion. We then proceed to the linear stability analysis and show that our theory introduces important corrections to previously derived results, both in the consistency at all wavelength and in the effects arising from the dynamical change of the cross-section. We also derive and analyze several analytical, fully nonlinear solutions of traveling wave type in two dimensions. Finally, we present results of preliminary experiments showing instability and re-stabilization elucidating the roles of rotation and boundary conditions. This research has been supported by NSERC and the University of Alberta.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dts86f371q2kid7798k1f3k8lc","2016-09-20 13:03:15",NULL
"3605","22","Triangles gone wild!","2016-09-29 16:30:00","2016-09-29 17:20:00","SAS 2102","Phillip Andreae",,"Meredith College",,"https://web.math.ncsu.edu/sumseries/fall2016/092916.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/p1cjiseb8q59uugd07vvpckr5s","2016-09-21 14:44:09",NULL
"3606","46","The knot concordance group (pre-talk)","2016-09-27 14:00:00","2016-09-27 14:45:00","SAS 2229","Jennifer Hom",,"Georgia Tech","Tye Lidman",,"The set of knots in S^3 under the operation of connected sum forms a monoid. By quotienting by an equivalence relation called concordance, we obtain the knot concordance group. We will discuss ways of understanding the structure of this group and introduce some concordance invariants coming from Heegaard Floer theory.","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5unh5o25tril5utt16v3armsto","2016-09-22 17:35:31","2016-09-22 17:37:13"
"3607","46","Knot concordance in homology spheres","2016-09-27 15:00:00","2016-09-27 16:00:00","SAS 2102","Jennifer Hom",,"Georgia Tech","Tye Lidman",,"The knot concordance group C consists of knots in S^3 modulo concordance. We consider C_Z, the group of knots in homology spheres that bound homology balls modulo homology bordisms of pairs. Matsumoto asked if the natural map from C to C_Z is an isomorphism. Adam Levine answered this question in the negative by showing the map is not surjective. We show that the image of C in C_Z is of infinite index. This is joint work with Adam Levine and Tye Lidman.","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fhad2un8aslk1b8c644mhd1img","2016-09-22 17:38:52","2016-09-26 10:26:04"
"3608","3","Spin characters of wreath products","2016-11-14 15:00:00","2016-11-14 16:00:00","SAS 4201","Naihuan Jing","http://www4.ncsu.edu/~jing/","NC State",,,"The symmetric group of n letters has two double central extensions
called the spin groups. Schur computed all irreducible representations of the spin groups as one of the fundamental examples in representation theory. He solved this problem by introducing the celebrated Schurs Q-functions that opened a new chapter of algebraic combinatorics beyond Jacobi. In 2000, the author and collaborators developed a new method of constructing spin characters using infinite dimensional Lie algebras, thus giving Schurs character theory a modern treatment which allows further generalization to wreath products. I will discuss the recent development of fixing the remaining character values of spin characters for wreath products and hyperoctahedral wreath products (jointly with Xiaoli Hu).","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dkvilbf4ri5dbvra9nh8uf94rc","2016-09-23 11:02:31","2016-11-01 12:56:35"
"3609","14","Departmental Tea and Cookies","2016-09-26 15:30:00","2016-09-26 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nl5qefkq57li4djs2239tsb0qc","2016-09-26 09:53:00",NULL
"3610","46","Drawing conclusions from drawing a square","2016-10-10 14:00:00","2016-10-10 15:00:00","SAS 4201","Annalisa Crannell ","http://www.fandm.edu/annalisa-crannell","Franklin and Marshall College","Irina Kpgan",,"Those of us who teach projective geometry often nod to perspective art as the spark from which projective geometry caught fire and grew.  This talk looks directly at projective geometry as a tool to illuminate the workings of perspective artists.  One of the surprising results of using this tool is that it implies that every quadrangle (whether convex or not) is the perspective image of a square. We will describe implications of this result for computer vision, for photogrammetry, for applications of piece-wise planar cones, and of course for perspective art and projective geometry.

Biography: Annalisa Crannell is a Professor of Mathematics at Franklin &amp; Marshall College and recipient of the MAAs most prestigious teaching award (the 2008 Deborah and Franklin Tepper Haimo Award).  Her early research was in topological dynamical systems (also known as &quot;Chaos Theory&quot;), but she has become active in working with mathematicians and artists on Projective Geometry applied to Perspective Art.   Together with mathematician/artist Marc Frantz, she is the author of Viewpoints: Mathematical Perspective and Fractal Geometry in Art.  She especially enjoys talking to non-mathematicians who havent (yet) learned where the most beautiful aspects of the subject lie.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6q1lkd5qgsang78q854jkmbv7s","2016-09-26 10:00:11",NULL
"3611","21","Kwangil Koh Lecture on Mathematics in Our Time Reception","2016-09-27 16:00:00","2016-09-27 16:30:00","Lobby",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/erv75n4t8ni2c3f36rubfl9d88","2016-09-26 10:09:52",NULL
"3612","4","Weighted Calderon-Zygmund estimates for weak solutions of degenerate and singular elliptic equations","2016-11-17 15:00:00","2016-11-17 16:00:00","SAS 4201","Tuoc Phan","https://www.math.utk.edu/~phan/","University of Tennessee","Khai Nguyen",,"Abstract: In this talk, we discuss about regularity estimates in weighted Lebesgue spaces for the gradients of solutions to a class of linear singular, degenerate elliptic Dirichlet boundary value problems over a bounded non-smooth domain. The coefficient matrix is symmetric, nonnegative definite, and both its  smallest and largest eigenvalues are proportion to a weight in a Muckenhoupt class. Under a smallness condition on the mean oscillation of the coefficients with the weight and a Reifenberg flatness condition on the boundary of the domain, we  establish a weighted  gradient estimate for weak solutions of the equation. A class of degenerate coefficients satisfying the smallness condition will be characterized.  A counter example to demonstrate the necessity of the smallness condition on the coefficients is given. The result reported in the talk can be viewed as the Sobolevs counterpart of the  Holders regularity estimates established by B. Fabes, C. E. Kenig, and R. P. Serapioni in 1982.

The talk is based on the joint work with D. Cao (Texas Tech) and T. Mengesha (U of Tennessee, Knoxville).","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/gl4lhvuplnr6npmvgdusvum5nk","2016-09-26 13:16:15","2016-11-01 16:30:29"
"3613","23","Applied Mathematics at Sandia National Laboratories: A Perspective from an Engineering Scientist","2016-11-16 16:00:00","2016-11-16 17:00:00","SAS 1102","Jordan Massad",,"Sandia National Laboratories","Pierre Gremaud","http://www4.ncsu.edu/~gremaud/Announcement-Massad.pdf",,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/72u0m79sptjucekec3b4uhap6g","2016-09-27 09:07:57","2016-11-07 16:12:18"
"3614","3","A q-Queens Problem","2016-10-03 15:00:00","2016-10-03 16:00:00","SAS 4201","Christopher R. H. Hanusa","http://qcpages.qc.cuny.edu/~chanusa/","Queens College",,,"The n-Queens Problem asks in how many ways you can place n queens on an n x n chessboard so that no two attack each other.  There has been no formula for the answer to this question... until now!

We develop a mathematical theory to address the more general question &quot;In how many ways can you place q chess pieces on a polygonal chessboard so that no two pieces attack each other?&quot;  The theory is geometrical and combinatorial in nature and involves counting lattice points that avoid certain hyperplanes.  

This is joint work with Thomas Zaslavsky and Seth Chaiken.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2cp9i94p9d2bmaqsfc2p3p8sug","2016-09-27 13:08:31","2016-09-27 14:54:35"
"3615","23","Learning styles: identifying and addressing different student approaches","2016-09-30 15:00:00","2016-09-30 16:00:00","SAS 4201","Bob Martin, Donna Petherbridge, and Barbie Windom",,"NC State","GIST Graduate Instructor Support and Tools","https://drive.google.com/open?id=0B8k3p4OEOPC5YXM4Y1ZzajFWQWs","GIST (Graduate Instructor Support &amp; Tools) will continue our teaching panel series with &quot;Learning Styles: identifying and addressing different student approaches.&quot;  Well be talking with Professor Bob Martin from the math department, Donna Petherbridge from DELTA, and Barbie Windom from the Undergraduate Tutorial Center.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/q1m90b95r71i3li1t5rb98regg","2016-09-27 16:04:30","2016-09-30 10:12:08"
"3616","9","Detection of Hidden Nodes in Complex Networks","2016-10-04 16:15:00","2016-10-04 17:15:00","Cox 306","Franz Hamilton",,"CQSB and Dept of Mathematics, NC State","Alun Lloyd",,"The identification of network connectivity from noisy time series is a problem found throughout the physical sciences. Accurately reconstructing the nodal interactions is critical to understanding the dynamics of the network. To address this, numerous methods have developed for connectivity estimation. However, the problem becomes significantly more complicated when we consider the possibility of hidden nodes within the network. These hidden nodes can lead to the identification of false connections, resulting in incorrect network inference. Detecting the presence of these hidden nodes, or more specifically the parts of the network they are acting on, is thus critical. In this talk we will propose a method for detecting hidden nodes in complex networks using nonlinear Kalman filtering. The Kalman filter is utilized to reconstruct the full connectivity matrix in a network, and by examining the filter covariance matrices we are able to identify the parts of the network affected by the hidden node.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2v498nuli22cguaton4uu7rgq0","2016-09-28 21:30:52",NULL
"3617","22","Math and art: The good, the bad, and the pretty","2016-10-11 16:30:00","2016-10-11 17:20:00","SAS 2102","Annalisa Crannell","http://www.fandm.edu/annalisa-crannell","Franklin & Marshall College",,"https://web.math.ncsu.edu/sumseries/fall2016/101116_bio.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0cjr1jb2879llu5r5qvoc5o4e8","2016-09-29 16:23:52","2016-10-11 11:46:40"
"3618","14","Grad School Informational Panel","2016-10-04 18:00:00","2016-10-04 19:00:00","SAS 2102",,,,,,"Are you applying to graduate school or curious if it might be a good fit for you? Come to the Grad School Informational Panel, hosted by Undergrads under Grads, on October 4th in SAS 2102 from 6pm-7pm. Pizza and drinks will be provided.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4tel6h9dq572r22j4vdhbjp0n0","2016-09-30 11:45:49",NULL
"3619","26","Model Development for PZT Bimorph Actuation Employed for Micro-Air Vehicle","2016-10-03 16:00:00","2016-10-03 17:00:00","SAS 4201","Nikola Bravo",,"NC State Mathematics Graduate Student",,,"In the talk, we discuss the development of models for PZT bimorph actuators used to power micro-air vehicles including Robobee. Due to highly dynamic drive regimes required for the actuators, models must quantify the nonlinear, hysteretic, and rate-dependent behavior inherent to PZT in these regimes. We employ the homogenized energy model (HEM) framework to model the actuator dynamics and numerically we illustrate the capability of the model to characterize the inherent hysteresis. This provides a comprehensive model, which can be inverted and implemented for certain control regimes.","kdcolem2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nkektiqpje5dks8ku70416ns5c","2016-10-02 17:44:13",NULL
"3620","9","Nonlinear filtering for periodic time-varying parameter estimation in an epidemic model","2016-10-11 16:15:00","2016-10-11 17:15:00","Cox 306","Andrea Arnold","https://sites.google.com/a/ncsu.edu/anarnold/","NC State, Mathematics and CQSB","Alun Lloyd",,"Many systems arising in biological applications are subject to periodic forcing, such as seasonal forcing in epidemiological systems.  In these types of applications, the forcing parameter is not only time-varying in nature but also has a periodic structure.  We present an approach to estimate periodic time-varying parameters using nonlinear filtering.  In particular, we employ the ensemble Kalman filter (EnKF) to estimate the periodic seasonal contact rate in an epidemic model for the spread of measles. 

In the literature, most parameter estimation methodology is aimed at parameters treated as constant or as drifting over time with no imposed structure.  The proposed technique imposes a periodic structure on the contact rate by treating it as a piecewise function consisting of parameters that change, e.g., each month.  The augmented EnKF implementation also allows for estimation of model initial conditions as well as the reporting probability, which is vital for predicting under-represented data such as the incidence data considered here.  In particular, results are demonstrated on real time-series data of measles case reports from various regions, including weekly reported cases in England and Wales (1948-1967).","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/63b2q4fmme0mpdsiikrb3gste4","2016-10-05 15:37:34","2016-10-05 15:55:59"
"3621","9","Modeling and controlling the acute inflammatory response","2016-10-18 16:15:00","2016-10-18 17:15:00","Cox 306","Judy Day","http://www.math.utk.edu/~judyday/","Univ Tennessee, Knoxville, Depts of Mathematics and Electrical Engineering & Computer Science","Mette Olufsen",,"The acute inflammatory response consists of a fascinating and complex cascade of events involving a multitude of immune cells and molecules concentrated on the goal of eliminating the offending agent (e.g. bacteria) and restoring equilibrium.  When the natural processes that govern the inflammatory response to severe infection or traumatic insult become dysregulated, intervention is necessary to restore homeostasis to the host. However, knowing how to intervene in order to help guide desirable outcomes is a difficult endeavor due to the complexity of the immune response. Using a canonical and highly nonlinear mathematical model of the systemic acute inflammatory response this talk will report on the use of the nonlinear model predictive control methodology to determine therapeutic intervention strategies in a diverse virtual patient population with limited measurement feedback.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0mkn2d7dmsj0sbutlhoean9nr4","2016-10-05 15:39:37",NULL
"3622","10","Mathematics and Mosquito-Borne Diseases","2016-10-14 15:00:00","2016-10-14 16:00:00","SAS 2102","Alun L. Lloyd","http://alun.math.ncsu.edu","Dept of Mathematics and CQSB, NC State University","Negash Medhin",,"Mosquito-borne infections are a major cause of human mortality. Recent years have seen an expansion of the range of some infections, such as dengue virus, and the emergence of others, such as chikungunya and Zika viruses. Mathematical modeling has played an important role in attempts to understand and control the transmission dynamics of such infections. In this talk I shall provide an introduction to mathematical modeling of mosquito-borne infections. I shall also discuss some of the work that my group has undertaken in this area, including the potential use of genetically modified mosquitoes as a control measure and models that explore this approach.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mvnjpas153rp4rj728peatqsa4","2016-10-09 18:01:13",NULL
"3623","22","A friendly introduction to maths most social subject, Graphs: colorings, cliques, and combinatorics","2016-10-20 16:30:00","2016-10-20 17:20:00","SAS 2102","Kyle Kloster","http://www4.ncsu.edu/~kakloste/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2016/102016.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/f4le3bdv68q5ltkdls22jbfm48","2016-10-10 17:18:35",NULL
"3624","19","Solving First Order Ordinary Differential Equations using Lie Symmetries","2016-10-12 16:30:00","2016-10-12 17:30:00","SAS Hall 2102","Michael Ruddy",,,,,"In this talk I will give a brief introduction to using Lie Symmetries to solve differential equations in the context of first order ODEs. The Lie symmetry group of an ODE is a group consisting of all the diffeomorphisms of the plane that 
preserve the set of solutions of the ODE. Finding a one parameter subgroup of this group allows to transform the equation of any first order ODE into a separable one and therefore easily solve it. If time, I will also show how the Moving Frame method of finding differential invariants can play a role.","esbarnar","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2r68fv4in6qeer9bk4ueko5svg","2016-10-10 22:26:10","2016-10-11 11:38:53"
"3625","38","A nonlinear conservation law modeling carbon sequestration","2016-11-28 14:00:00","2016-11-28 16:00:00","SAS 3282","Elisabeth Brown",,,,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/9661pmlk6fljtolhtsholtnjuo","2016-10-11 10:17:50",NULL
"3626","6","Sparse representations and fast algorithms for Kohn-Sham orbitals","2016-11-02 15:00:00","2016-11-02 16:00:00","SAS 2102","Anil Damle",,"UC Berkeley",,,"In this talk we explore the question of how to build localized basis functions for a subspace arising in Kohn-Sham Density Functional Theory (KSDFT). This includes a brief introduction to KSDFT and discussion of the computational benefits of working with localized orbitals. Our methodology provides a simple, robust, and efficient means for constructing localized basis functions based on a column-pivoted QR factorization (QRCP). Importantly, our methods avoid the use of an optimization procedure and hence have no dependence on an initial guess for the localized basis. Finally, we discuss recently developed algorithms that significantly accelerate the method by avoiding explicit computation of a large QRCP.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5ub3c6pi9uifpio7g35cduo9c0","2016-10-11 11:26:41","2016-10-17 10:03:54"
"3630","26","A Nonlinear Conservation Law Modeling Carbon Sequestration","2016-11-21 16:00:00","2016-11-21 17:00:00","SAS 4201","Elisabeth Brown",,"NC State",,,"A quasi-linear hyperbolic partial differential equation with a discontinuous flux models geologic carbon dioxide (CO2) migration and storage. Dual flux curves emerge in this model, giving rise to flux discontinuities. One flux describes the invasion of the plume into pore space, and the other captures the flow as the plume leaves CO2 bubbles behind, which are then trapped in the pore space. We prove the existence of an entropy solution of the Cauchy problem for any initial CO2 plume using wave-front tracking. During our analysis, we introduce a new construction with cross-hatch characteristics in regions of the characteristic plane where the solution is constant, and the characteristic speed depends on which flux is invoked. We present a computer simulation that tracks CO2 plume migration in the characteristic plane. Some wave interactions yield novel phenomena due to the dual flux, such as shock-rarefaction interactions that would persist for all time with a single flux, here are completed in finite time.","kdcolem2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/s9nmc82an378llacsv51ro26e4","2016-10-11 16:22:52","2016-11-18 12:06:23"
"3632","46","Homotopy type of circle graphs complexes motivated by extreme Khovanov homology","2016-11-21 16:00:00","2016-11-21 17:00:00","SAS 1102","Jozef H. Przytycki",,,"R. Sazdanovic",,"Gonzalez-Meneses, Manchon and Silvero showed that the extreme Khovanov homology of a link diagram is isomorphic to the reduced (co)homology of the independence simplicial complex obtained from a bipartite circle graph constructed from the diagram. In this talk we conjecture that this simplicial complex is always homotopy equivalent to a wedge of spheres. In particular, its homotopy type, if not contractible, would be a link invariant and it would imply that the extreme Khovanov homology of any link diagram does not contain torsion. We prove the conjecture in many special cases and find it convincing to generalize it to every circle graph (intersection graph of chords in a circle). In particular, we prove it for the families of cactus, outerplanar, permutation and non-nested graphs. Conversely, we also give a method for constructing a permutation graph whose independence simplicial complex is homotopy equivalent to any given finite wedge of spheres. We also present some combinatorial results 
on he homotopy type of finite simplicial complexes
which sheds light on some results by Csorba, Nagel and Reiner, Jonsson, and Barmak. We study the implications of our results to Knot Theory; more precisely, we compute the real-extreme Khovanov homology of torus link 
T(3,q) and obtain examples of H-thick knots whose extreme Khovanov homology groups are separated either by one or two gaps as long as desired. We show also, playing even Khovanov homology versus the odd one, that 
there are knots such that for every diagram the potential extreme Khovanov homology is different than real extreme  Khovanov Homology (the first such example is the torus knot T(4,5)). 
This is a joint work with Mauritania Silvero.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/0iina2hhq9ktb62kgjpgcbtq3o","2016-10-16 17:59:26","2016-11-20 15:16:14"
"3633","14","Departmental Tea and Cookies","2016-11-02 14:30:00","2016-11-02 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/a4luvf1u4alaiej2ufmv80qri8","2016-10-17 10:05:34",NULL
"3634","14","Departmental Tea and Cookies","2016-11-30 14:30:00","2016-11-30 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1eq3gonft413p392qtqsr92ev8","2016-10-17 10:26:55",NULL
"3635","23","Fundamentals of Webdesign","2016-10-21 15:00:00","2016-10-21 16:00:00","SAS 4201","Seyma Shabbir",,"NC State",,,"Effective webpages are an increasingly important medium for disseminating information related to classes and research. For TAs, they provide a critical way to share material with your class whereas for those entering the job market, they are often checked by potential employers interested in obtaining more information about candidates. Hence it is important to construct and maintain your webpage in a manner that is both easy and professional.

In this session, Seyma will discuss the use of Wordpress, which is one of the most widely used applications for webpage design.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fic7jpstepet70idaqrkomgp3o","2016-10-17 10:56:34",NULL
"3636","23","CVs, research and teaching statements","2016-10-26 16:00:00","2016-10-26 17:00:00","SAS 1102","Faculty panel",,,"Pierre Gremaud",,"A faculty panel will lead a discussion on how to put together your CV as well as research and teaching statements. These are essential steps if you want to be successful on the job market.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8r1dkumbi5k7ssn51cgt44dt5c","2016-10-18 11:19:31",NULL
"3637","3","Positive expressions for skew divided difference operators","2016-10-24 15:00:00","2016-10-24 16:00:00","SAS 4201","Ricky Liu","http://www4.ncsu.edu/~riliu/","NC State",,,"For any pair of permutations, Macdonald defines a skew divided difference operator and shows how these operators can be used to compute the structure constants for Schubert polynomials. We will show that any skew divided difference operator can be written explicitly as a polynomial in the degree 1 divided difference operators with positive coefficients, which settles a conjecture of Kirillov. The proof relies on various tools from the braided Hopf algebra structure of the Fomin-Kirillov algebra.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/te2eu3rmrior93njo7o62m1b6o","2016-10-19 12:36:05",NULL
"3638","26","Development and Calibration of Fuel Temperature Models Using the Bison Fuel Performance Code","2016-10-24 16:00:00","2016-10-24 17:00:00","SAS 4201","Kayla D. Coleman",,"NC State Mathematics Graduate Student",,,"Modeling the behavior of nuclear reactors is important to understanding and predicting the performance of new and existing fuel systems. In cases where experimental data can be prohibitively expensive, one can use high-fidelity codes to calibrate parameters in low-fidelity models. Bison is a highly validated fuel performance code used to simulate fuel performance under various conditions. In this talk, we will discuss a progressive series of low-order fuel performance models we developed using high to low-fidelity methods and simulated data from Bison fuel performance codes. We will also discuss a few physics-based models for which we calibrate the effective thermal conductivity of the fuel-gap-clad region using the Delayed Rejection Adaptive Metropolis (DRAM) algorithm.","kdcolem2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1hrvbraup13nb1i0lc33lb9ilk","2016-10-20 12:18:11",NULL
"3639","22","Do robots dream of proofs?","2016-10-27 16:30:00","2016-10-27 17:20:00","SAS 2102","Cynthia Vinzant","http://www4.ncsu.edu/~clvinzan/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2016/102716.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dns6qqdonakafehsa822l6gnv4","2016-10-20 16:15:47",NULL
"3640","1","A PDE system modeling biological network formation","2017-04-10 16:00:00","2017-04-10 17:00:00","SAS 1102","Peter Markowich","http://www.damtp.cam.ac.uk/people/p.markowich/","University of Cambridge and University of Vienna","Alina Chertok",,"Transportation networks are ubiquitous as they are possibly the most important building blocks of nature. They cover microscopic and macroscopic length scales and evolve on fast to slow times scales. Examples are networks of blood vessels in mammals, genetic regulatory networks and signaling pathways in biological cells, neural networks in mammalian brains, venation networks in plant leafs and fracture networks in rocks. We present and analyze a PDE (continuum) framework to model transportation networks in nature, consisting of a reaction-diffusion gradient-flow system for the network conductivity constrained by an elliptic equation for the transported commodity (fluid).","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/8tccbjlhc3362n77ivuungut4k","2016-10-24 11:30:38","2017-03-29 14:11:38"
"3641","38","Modeling cerebral autoregulation during orthostatic stress in the presence of aging and hypertension","2016-11-01 13:00:00","2016-11-01 15:00:00","SAS 3282","Greg Mader",,,,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/lvp7i2nsoupktssqqjhke1k2q4","2016-10-25 14:53:12",NULL
"3642","22","Cayleys formula","2016-11-03 16:30:00","2016-11-03 17:20:00","SAS 2102","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,"https://web.math.ncsu.edu/sumseries/fall2016/110316.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/l4ac0rdn6rme6n16pvte6r3q64","2016-10-25 19:56:42",NULL
"3643","22","Curvature and pizza","2016-11-10 16:30:00","2016-11-10 17:20:00","SAS 2102","Tye Lidman","https://www.ma.utexas.edu/users/tlid/","UT Austin",,"https://web.math.ncsu.edu/sumseries/fall2016/111016.pdf",,"emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/60ciqh43g0ui914ii41cfanc9o","2016-10-27 13:19:45",NULL
"3644","26","Analyzing Multistationarity in Chemical Reaction Networks","2016-10-31 16:00:00","2016-10-31 17:00:00","SAS 4201","Zev Woodstock",,"NC State Mathematics Graduate Student",,,"Multistationary chemical reaction networks are of interest to scientists and mathematicians alike. While some criteria for existence of multistationarity exist, obtaining explicit reaction rates and steady states that exhibit multistationarity for a given network  in order to check nondegeneracy or determine stability of the steady states, for instance  is nontrivial.  Nonetheless, we accomplish this task for a certain family of sequestration networks by generalizing Craicun and Feinbergs Determinant Optimization Method (http://arxiv.org/abs/1508.07522).","kdcolem2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/vn8m6qi3diip35sudn1l8qsrlo","2016-10-28 07:17:43",NULL
"3645","14","Loek Helminck Retirement Party","2016-11-16 14:00:00","2016-11-16 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/c22hddgdj0b43md677tgrlnq90","2016-11-01 12:27:05",NULL
"3646","3","On vertex algebraic constructions of simple affine vertex algebras and their modules","2016-11-07 15:00:00","2016-11-07 16:00:00","SAS 4201","Drazen Adamovic","https://web.math.pmf.unizg.hr/~adamovic/","University of Zagreb, Croatia",,,"In this talk we shall review some recent papers on realizations of affine vertex algebras and their applications in representation theory. In particular, we discuss the principal realization of A_1^(1) modules at the critical level and the realization of admissible A_2^(1) modules connected with vertex algebras appearing in LCFT.  We shall discuss possible generalizations of these constructions to other affine vertex algebras and W-algebras. Some parts of this talk are based on a joint work with N. Jing and K. Misra.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ce2cq8e97g03kk9ub3qfvi34co","2016-11-01 12:58:57","2016-11-01 14:57:26"
"3648","26","Sensitivity Analysis in Poro-visco-elasticity","2016-11-07 16:00:00","2016-11-07 17:00:00","SAS 4201","Marcella Noorman",,"NC State Mathematics Graduate Student",,,"Poro-elastic and poro-visco-elastic models find many applications in bioengineering and medicine. Inspired from applications in geophysics and petroleum engineering, they are more and more frequently being applied to biological tissues. For many of these biological applications, the boundary data plays a crucial role. In a recent theoretical and numerical analysis of poro-elastic and poro-visco-elastic models, the time regularity of the imposed boundary traction was identified as a crucial factor in guaranteeing boundedness of the solutions. Here, we further extend that analysis by studying the sensitivity of model solutions to the imposed boundary traction. Nonlinear coupling in the model causes difficulty when implementing traditional methods for sensitivity analysis (such as sensitivity equations). For this reason, we use instead the lesser known complex step method which uses the Cauchy- Riemann equations to compute sensitivities.","kdcolem2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1bcbud86o4pp58qesfqbcdaua4","2016-11-03 11:17:46",NULL
"3649","4","Some selection problems in the theory of viscosity solutions","2017-03-23 15:00:00","2017-03-23 16:00:00","SAS 4201","Hung Tran","http://www.math.wisc.edu/~hung/","University of Wisconsin Madison ","Khai Nguyen",,"I will explain some interesting selection problems in nonlinear PDEs. The basic question is about how to select one good solution out of many reasonable ones. A question of this type led to the whole theory of viscosity solutions in 1980s. Then I will focus on the vanishing discount problem and describe the main results, which solve an open question also in 1980s. This is a joint work with Ishii and Mitake.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/72f4udcgenvnan7enun32onhlk","2016-11-04 14:54:04","2017-03-15 11:42:33"
"3650","9","A coupled model of the inflammatory response and the cardiovascular system; A Mechanistic Mathematical Model of Progestin and Estrogen Based Contraception","2016-11-08 16:15:00","2016-11-08 17:15:00","Cox 306","Renee Brady - Andrew Wright",,"NC State, Mathematics and Biomathematics",,,"Renee Brady

Title: A coupled model of the inflammatory response and the cardiovascular system.

Abstract: The magnitude of the initial reaction of the body to pathogenic microbial infection or severe tissue trauma  threats posed by pathogens and restore the body to a healthy state. Inflammation caused by surgery or LPS increases the parasympathetic activity due to the neuroinflammatory reflex. The increased vagal tone increases the risk of vasovagal syncope, as seen in the early postsurgical phase. In this talk, we present a coupled model of the inflammatory response and the cardiovascular system using ordinary differential equations. We hypothesize that blood pressure and heart rate are affected by changes in the pro-inflammatory mediators via changes in temperature and the production of nitric oxide. Mathematical modeling of the cardio-inflammatory response has the potential to provide important insight into an idea of the direct connection between heart rate variability and inflammation, and thus deliver information on who to survey more frequently after surgery to !
 circumvent sudden fainting episodes. This may lead to the development of preoperative therapy that can be used to shorten a patients hospital stay, reducing heath care costs and improving patients quality of life.



Andrew Wright

Title: A Mechanistic Mathematical Model of Progestin and Estrogen Based Contraception

Abstract: Contraceptive drugs intended for family planning are used by the majority of married or in-union women in almost all regions of the world. Two of the most prevalent types of these contraceptives are hormonal treatments   Using these additional mechanisms we can predict relative daily blood concentrations of key hormones during a contraceptive state achieved through progestins or estrogens. We test the model against clinical data from various doses of a specific progestin and data from a combined estrogen and progestin treatment. This gives possible rise to understanding bioavailability of the drug we are introducing and other difficult to quantify ideas that can be used as indexes for comparison of drugs. An accurate understanding of this idea presents opportunity for dose testing on models and possible further information for patient specific applications in the future.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o93do9jlmfde9pbm1a3cab48ak","2016-11-06 19:02:01","2016-11-06 19:03:06"
"3651","14","Colloquium Tea","2016-11-10 15:30:00","2016-11-10 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/n1643bot83be0t4ikod3qrfo2o","2016-11-07 12:45:55","2016-11-07 12:46:49"
"3652","21","AMS-NZMS Maclaurin Lecture: Siegels problem on small volume lattices","2016-11-12 17:00:00","2016-11-12 18:00:00","SAS 2203","Gaven J. Martin",,"Distinguished Professor of Mathematics, Massey University New Zealand",,"http://www.math.ncsu.edu/News/gavenmartin.pdf","Reception to follow","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/icthrnmlq38cm9bnhm9qcamlas","2016-11-07 14:39:40","2016-11-08 10:40:10"
"3653","21","AMS Fall Southeastern Sectional Meeting","2016-11-12 08:00:00","2016-11-13 17:00:00","SAS Hall, Riddick Hall, and Park Shops",,,,,"http://www.ams.org/meetings/sectional/2241_progfull.html",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/38r0j8lsd67jik7m46k2beel2o","2016-11-07 18:11:51","2016-11-08 12:23:51"
"3654","2","Airborne Reconnaissance, Triangulation Problems and the Error Ellipse","2016-11-15 14:30:00","2016-11-15 15:30:00","SAS 4201","Dr. Marvin Eargle",,,"Alina Chertok",,"This is a more detailed look at one of the major problems of airborne reconnaissance, target location.  We will look at how we create a line of bearing to the target, how we combine many lines of bearing to estimate a solution, how we incorporate measurement errors into the calculation, and how we create an error ellipse about the result.

Dr.  Marvin Eargle received his Ph.D. in applied mathematics from NC State in 1968 under advisor Dr. Walter Harrington.  Dr. Eargle was a member of the mathematics faculty at Appalachian State University from 1969 to 1982. From 1982 Dr. Eargle worked as an engineering specialist at E-Systems in Greenville, TX.   In 1999 he was recruited by a start-up called ComCept, Inc.  Dr. Eargle retired  as an engineering fellow in 2004.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/lpvaln2efqseph2mlp92vrvh94","2016-11-08 12:41:33","2016-11-10 12:02:47"
"3655","14","Graduate Student Seminar","2016-11-14 16:30:00","2016-11-14 17:30:00","SAS 2102",,,,,,"There will be four 10 minutes presentations by graduate students","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/v6fbntrp3t15e7qmpel0cmb598","2016-11-08 12:47:04",NULL
"3656","22","Intro to Airborne Reconnaissance and Pythagorean Triples","2016-11-15 16:30:00","2016-11-15 17:20:00","SAS 2102","Dr. Marvin Eargle",,,,,"This is an introduction to airborne reconnaissance, a brief discussion of signals intelligence, a look at some of the airplanes and some of the companies that build them.  These companies provide jobs for mathematicians, engineers and computer scientists.  The Pythagorean Triple part has to do with rearranging the unit squares of an integer square to recombine them into more Pythagorean Triples that most people can imagine.


Dr.  Marvin Eargle received PhD (1968) in Applied Mathematics from NCSU under advisor Dr. Walter Harrington.  Dr. Eargle was a member of the Math faculty at Appalachian State University from 1969 to 1982. From 1982 Dr. Eargle worked as an Engineering Specialist E-Systems in Greenville, TX.   In 1999 he was recruited by a start-up called ComCept, Inc.  Dr. Eargle retired  as an Engineering Fellow in 2004.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2a2aj86vj5ne2f8e350mlqlqvo","2016-11-08 12:48:06","2016-11-10 11:28:39"
"3657","6","LU Preconditioning for Sparse Least Squares","2016-11-29 15:00:00","2016-11-29 16:00:00","SAS 4201","Gary Howell NCSU OIT and Marc Baboulin U Paris Sud",,,,,"Consider choosing $x$ to minimize $\|Ax -b \|_2$  where $A$ has more rows than columns and is full rank.   Iterative techniques can be applied to solve the normal equations $A^T A x = A^T b$  Since a lower triangular $L$ satisfying $LU = A$ is typically much better conditioned than $A$, the alternative system of equations  $L^T L (Ux) = inv(U) b$ typically converges in fewer iterations. Write $L^T = [L_1^T | L_2^T]$ where $L_1$ is square and lower triangular. $L inv(L_1) = [I|C^T], C = L_2 inv(L_1)$,  is usually better conditioned than $L$, so solving the normal equations corresponding to $L inv(L_1)$ is yet faster.  Since the smallest singular values of $L inv(L_1)$ are one, it is easy to estimate the condition number and required number of iterations. When $A$ is nearly square, the $L inv(L_1)$ iteration  may require fewer flops and storage than a sparse $QR$ factorization.

For an incomplete LU factorization,  equality in $LU = A$ is not as exact, but we can iterate with $A inv(U) inv(L_1)$. For example, the LU factorization could be performed in lower precision arithmetic. So far numerical experiments use matlab, octave, and julia.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fj4kf7ihab1dd99gjfbmt2a90g","2016-11-08 15:02:47","2016-11-08 15:03:42"
"3659","14","Departmental Tea and Cookies","2016-11-17 15:30:00","2016-11-17 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/cr0bfali07gjac2rjbb1bllee4","2016-11-14 08:45:43",NULL
"3660","14","Reception for Dr. Marvin Eargle","2016-11-15 15:30:00","2016-11-15 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/fv6f5eoa7rmiir7te71qbq3cqc","2016-11-14 14:28:39",NULL
"3661","24","MGSA Thanksgiving Potluck","2016-11-17 12:30:00","2016-11-17 14:00:00","SAS 4104",,,,"Mathematics Graduate Student Association",,"Please join us for the MGSA Thanksgiving Potluck.  All math faculty, staff and grad students are invited.  MGSA will provide the turkey and gravy and we ask that you bring a side dish to share or a $5 donation to the event.","secrifo","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/oh41ecoi4rc4v77svh88g2u25k","2016-11-15 12:48:05",NULL
"3662","46","Synchronization Problems and Manifold Learning on Fiber Bundles","2017-01-18 16:00:00","2017-01-18 17:00:00","SAS 4201","Tingran Gao","https://services.math.duke.edu/~trgao10/","Duke University","Irina Kogan",,"A graph synchronization problem over a group searches for an assignment of group elements to the vertices of the graph, such that the two group elements on any two vertices connected by an edge satisfies a compatibility constraint specified by another group element prescribed on that edge. In this talk, we relate synchronization problems on any fixed graph Gamma over group G to the moduli space of flat principal G-bundles on Gamma, i.e. the G-representation variety of the fundamental group of Gamma (viewed as a topological space). This fiber bundle formulation lends itself naturally to many statistical learning problems where information needs to be inferred from only pairwise comparisons of a collection of object data. As an application in manifold learning, we design a diffusion geometry framework on fiber bundles for biological shape classification problems in evolutionary anthropology.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ebff0b1epack4oovescldjdir0","2016-11-16 14:29:19","2017-01-13 14:39:33"
"3663","10","Optimization Under Uncertainty with Applications to Electrical and Energy Systems","2016-11-22 16:30:00","2016-11-22 17:30:00","Daniels Hall 218","Anderson Rodrigo de Queiroz",,"North Carolina State University",,,"In this work we discuss topics about the role of optimization and decision-making applied to different problems in electric and energy systems.  We present power generation problems at different time scales with renewable integration. 
Mathematical formulations and solution strategies are addressed such as multi-stage stochastic linear programs (SLP-T) and sampling-based decomposition algorithms (SBDA) used to solve SLP-T versions of hydro-thermal coordination problems. We also show a description of a SBDA parallel implementation and discuss findings of recent research.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/o6vl1knmpciem7cbqcou03jb60","2016-11-17 11:02:13",NULL
"3664","22","Undergraduate Research Presentations","2016-12-01 16:30:00","2016-12-01 17:20:00","SAS 2102","Undergraduate researchers",,"NC State",,"https://web.math.ncsu.edu/sumseries/fall2016/120116.pdf","Predicting Graphs: Bayesian Knowledge Tracing in Open Ended Problems
Joshua Cook

How can a computer tell if you understand how to solve a problem? Learner models in intelligent tutoring systems must do this every day. Sure, if the problems use a single skill and you can only answer correctly or incorrectly, we can use some simple probabilities and a little of Bayes theorem to guess. But what if the problem is open ended, and there are many solutions with varying quality? For these problems, we need a different approach. Our research attempts to find student knowledge in these problems by modeling answers as graphs. This allows us to use simple graph algorithms to derive answer quality, and leverage existing learner models to find out what students know. This talk will discuss existing learner models like Bayesian Knowledge Tracing and Performance Factors Analysis, and ideal path identification in a graph using value iteration. (Faculty Mentor: Dr. Colin Lynch)

Edge Probability
Trevor Gasdaska

I will explore Graph Edge Probability: Given the degrees of vertices in a graph, what are the chances any two vertices are connected by an edge? I will assume no prior knowledge and work from What is a graph? to introducing Edge Probability as a function in order to prove things about it. This problem has exciting applications in Social Networking and Marketing. (Faculty Mentor: Dr. Hoon Hong) 

Dimension Reduction for Survival Analysis Cure Model
Daniel Harper

Survival analysis is the field of statistics that is concerned with explaining how long an event of interest takes to occur, for example, death, remission, germination of a plant, breakdown of machine, etc.  Some individuals will not have the event by the end of the study (we say their times are censored), and survival analysis techniques correctly account for the censoring issue.  A main goal of survival analysis is to try to partially explain the time to event based on other explanatory variables, just as in typical regression settings.  However, it is becoming more common (weve all heard of big data) that the number of explanatory variables greatly exceeds the sample size, which excludes using standard survival regression techniques. A common application would be to use a persons gene expression profile to predict how long he or she survives after diagnosis of some disease.  We will compare the performance of different dimension reduction techniques that have been proposed in the statistical literature in the context of survival analysis. (Faculty mentor: Dr. Daniel Frobish)

Cracking Kryptos
Isaac Sunseri

Have you ever wondered how spies and mathematicians break secret codes in movies like A Beautiful Mind or Enigma? In this talk, were going to look at the famous Kryptos cipher and examine the techniques used to decrypt it. The cipher is broken into 4 sections; the first three of which have already been solved, while the final piece remains a mystery after over 25 years. Together, were going to decode part two of the Kryptos cipher, after looking at cryptanalysis theory and practical methods used to decipher a Vigenre encryption. (Faculty mentor: Dr. Ernest Stitzinger)","emeehan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ogtbciagfe590rb64dljv4u36s","2016-11-17 11:02:26","2016-11-21 12:29:39"
"3665","21","Triangle Lectures in Combinatorics","2016-11-19 09:15:00","2016-11-19 17:00:00","SAS Hall 2203",,,,"Ricky Liu NCSU, Seth Sullivant NCSU and Cynthia Vinzant NCSU","http://www.math.ncsu.edu/TLC/","The Triangle Lectures in Combinatorics is a series of combinatorial workshops held each semester on a Saturday in the Research Triangle region of North Carolina, funded by the National Science Foundation.  The workshop this fall, the 14th installment of the Triangle Lectures in Combinatorics, will be hosted by North Carolina State University in Raleigh, North Carolina on Saturday, November 19, 2016.  It will include four one hour invited talks as well as coffee breaks and ample time for discussions throughout the day.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nq3jfona0ecd5lhlilppr14crc","2016-11-17 11:04:37","2016-11-17 11:05:18"
"3666","9","Robust fitting of state-space models for reliable fish stock assessment","2016-11-29 16:15:00","2016-11-29 17:15:00","Cox 306","William Aeberhard",,"Department of Mathematics and Statistics, Dalhousie University, Canada",,,"The sustainable management of fisheries strongly relies on the output of fish stock assessment models fitted to scarce and noisy data. State-space models represent a relevant general framework for accounting for both measurement error and a complex dependence structure of latent (unobserved) random variables. Classical estimation of fixed parameters in such models, for instance by maximizing an approximated marginal likelihood, is known to be highly sensitive to the correct specification of the model. This sensitivity is all the more so problematic since assumptions about latent variables cannot be verified by the data analyst. We introduce robust and consistent estimators for general state-space models which remain stable under deviations from the assumed model. These estimators are shown to yield reliable inference for fish stock assessment in various scenarios.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1sck4qev6q4u6abakkoe12rsfs","2016-11-21 09:35:51",NULL
"3667","23","Applying Tools for Geospatial Trajectory Analysis to Space Situational Awareness","2016-11-29 10:00:00","2016-11-29 11:00:00","SAS 4201","Erin Acquesta",,"Sandia","Pierre Gremaud","http://www4.ncsu.edu/~gremaud/Acquesta_NCSU20161129.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/pqg7p3h8ajpujldv2s6a1ndhss","2016-11-23 17:25:22","2016-11-24 12:28:06"
"3668","4","Bifurcations of Heterodimensional Cycles with two Hyperbolic Equilibrium Points","2017-01-25 15:00:00","2017-01-25 16:00:00","SAS 4201","Fengjie Geng",,"School of Science,  China University of Geosciences ","Xiao-Biao Lin",,"The bifurcations  of heterodimensional cycles are investigated in this paper.  Under some generic conditions, we show bifurcation surfaces for the  persistence of  heterodimensional cycles, the existence of  homoclinic orbits or periodic orbits and  the coexistence of persistent heterodimensional cycle and  the bifurcated periodic orbit. Our strategy is based on moving frame, the fundamental solution matrix of linear variational system is chose  to be an active local coordinate system along original heterodimensional cycle, which can clearly display the property of the orbits for some sufficiently large time.","lvbociu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/r9fqujrlr4hgl7915pqgb67hto","2016-12-02 12:06:44","2017-01-24 12:11:00"
"3669","3","Restricted Stirling and Lah numbers and their inverses","2017-01-23 15:00:00","2017-01-23 16:00:00","SAS 4201","Clifford Smyth","https://www.uncg.edu/mat/people/people.php?username=cdsmyth","UNC Greensboro",,,"Let $s(n,k)$, $S(n,k)$, and $L(n,k)$ be the Stirling numbers of the first kind, Stirling numbers of the second kind, and the Lah numbers, respectively.  It is well known that the inverse of the infinite lower triangular matrix $[s(n,k)]_{n,k \geq 1}$ is $[(-1)^{n-k} S(n,k)]_{n,k \geq 1}]$, the inverse of $[S(n,k)]_{n,k}$ is $[(-1)^{n-k} s(n,k)]_{n,k}$, and the inverse of $[L(n,k)]_{n,k}$ is $[(-1)^{n-k} L(n,k)]_{n,k}$.

More generally, we consider restricted versions of these numbers, $s(n,k,R)$, $S(n,k,R)$, and $L(n,k,R)$, for arbitrary subsets $R$ of natural numbers. These are defined to be the number of ways of partitioning a set of size $n$ into $k$ non-empty cycles (for Stirling numbers of the first kind), subsets (for Stirling numbers of the second kind) or ordered lists (for Lah numbers) with the size of each cycle, subset, or list in $R$.  (To recover $S(n,k)$, $s(n,k)$, and $L(n,k)$, take $R$ to be the set of natural numbers.)

If $R$ contains $1$ then the matrices $[S(n,k,R)]_{n,k}$, $[s(n,k,R)]_{n,k}$ and $[L(n,k,R)]_{n,k}$ are all invertible and their inverses have integer entries.  We obtain combinatorial formulas for the entries of these inverse matrices, expressing
each such entry as the difference between the sizes of two explicitly defined sets of forests. (Note, that some of these entries must indeed be negative.)

For $S(n,k,R)$ and $L(n,k,R)$ and for certain $R$ we can do better: each $(n,k)$ entry of the inverse will have a predictable sign, $\sigma(n,k)$, and its magnitude will be the size of a single explicitly defined set of forests.  Among these special $R$s are those which contain $1$ and $2$ and which have the property that for all odd $n$ in $R$ with $n \geq 3$ we have $n-1$ and $n+1$ in $R$.  (For these $R$, the sign of the $(n,k)$ entry is $(-1)^{n-k}$, as when $R$ is the set of the natural numbers.)

Our proofs depend in part on two combinatorial interpretations of the coefficients of the compositional inverse of a power series. This is joint work with David Galvin of the University of Notre Dame and John Engbers of Marquette University.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/m8hrjjueq20qapcrfhfrma9fmc","2016-12-05 11:03:50","2016-12-14 15:30:09"
"3670","4","Fractional Operators with Inhomogeneous Boundary Conditions: Analysis, Control, and Discretization","2017-04-12 15:00:00","2017-04-12 16:00:00","SAS 4201","Harbir Antil",,"George Mason University","Lorena Bociu",,"In this talk we introduce new characterizations of spectral fractional Laplacian to incorporate nonhomogeneous Dirichlet and Neumann boundary conditions. The classical cases with homogeneous boundary conditions arise as a special case. We apply our definition to fractional elliptic equations of order s in (0,1) with nonzero Dirichlet and Neumann boundary conditions. Here the domain Omega is assumed to be a bounded, quasi-convex Lipschitz domain. To impose the nonzero boundary conditions, we construct fractional harmonic extensions of the boundary data. It is shown that solving for the fractional harmonic extension is equivalent to solving for the standard harmonic extension in the very-weak form. The latter result is of independent interest as well. The remaining fractional elliptic problem (with homogeneous boundary data) can be realized using the existing techniques. We introduce finite element discretizations and derive discretization error estimates in natural norms, which are confirmed by numerical experiments. We also apply our characterizations to Dirichlet and Neumann  boundary optimal control problems with fractional elliptic equation as constraints.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qqajnfanib3f3r8apndjsg2hm0","2016-12-05 20:49:23","2017-04-04 11:56:25"
"3671","4","Control Problems in the Wasserstein Space and Applications to Multi-Agent Systems","2017-03-01 15:00:00","2017-03-01 16:00:00","SAS 4201","Antonio Marigonda","http://www.di.univr.it/?ent=persona&id=6498&lang=it","University of Verona, Italy ","Khai Nguyen",,"We introduce and study some optimal control problems in the space of probability measures endowed with the Wasserstein distance, where the dynamics is given by a (controlled) continuity equation.

The main motivation is to face situations in finite-dimensional control systems evolving deterministically where the initial position of the controlled particle is not exactly known, but can be expressed by a probability measure on R^d, or to describe at a macroscopical level the behaviour of multi-agent systems, i.e., systems where the number of agents is so high to make unpractical a description of the behaviour of each single agent, while only a statistical description of some parameters of the systems(e.g. the densities of the agent in the space) is feasible.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/59glnubjmiutbok6bmadtnngag","2016-12-06 11:35:59","2017-02-24 10:15:31"
"3672","3","Positivity in T-equivariant K-theory of flag varieties associated to Kac-Moody groups","2017-01-30 15:00:00","2017-01-30 16:00:00","SAS 4201","Seth Baldwin","http://www.unc.edu/~sethba/","UNC Chapel Hill",,,"The cohomology ring of flag varieties has long been known to exhibit positivity properties. One such property is that the structure constants of the Schubert basis with respect to the cup product are non-negative. Brion (2002) and Anderson-Griffeth-Miller (2011) have shown that positivity extends to K-theory and T-equivariant K-theory, respectively. In this talk I will discuss recent work (joint with Shrawan Kumar) which generalizes these results to the case of Kac-Moody groups.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/uteoj0g6h7rte81o29ppa87tks","2016-12-12 08:33:10","2017-01-24 17:07:39"
"3673","36",,"2017-01-20 15:00:00","2017-01-20 16:00:00","SAS 4201","Radmila Sazdanovic and Moody Chu",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ijgdkuvvgk5vstokp4a7o9gf70","2016-12-15 10:35:48",NULL
"3674","36",,"2017-02-03 15:00:00","2017-02-03 16:00:00","SAS 4201","Hien Tran and Nathan Reading",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dutlqj30rbk08j6fgnj9o1okfg","2016-12-15 10:36:50",NULL
"3675","36",,"2017-02-17 15:00:00","2017-02-17 16:00:00","SAS 4201","Ernie Stitizinger and Alen Alexanderian",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/cem9l2kq7r5mvc0rje63esp4es","2016-12-15 10:37:57",NULL
"3676","36",,"2017-03-17 15:00:00","2017-03-17 16:00:00","SAS 4201","Sharon Lubkin and Kailash Misra",,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/las3gu0jrfs3pa2cdbfsobojqs","2016-12-15 10:38:45",NULL
"3677","15","Matrix CUR decomposition","2017-02-08 16:30:00","2017-02-08 17:30:00","SAS 2229","Arvind Saibaba","http://www4.ncsu.edu/~asaibab/","NC State",,,"CUR decomposition is a low-rank matrix decomposition that is formed using a  small number of actual columns and actual rows of the data matrix. Since this decomposition is explicitly constructed using entries from the actual data set, CUR decomposition may be interpretable by practitioners; for this reason, it is sometimes preferable to the Singular Value Decomposition. I will explain various deterministic and randomized algorithms for computing the CUR decomposition and methods to analyze its accuracy. I will also explain how CUR decomposition can be applied to areas such as recommendation systems, facial recognition and handwriting digit classification.","jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/jd7d1lv18o47soqciqf3m3t5a4","2016-12-19 10:36:46","2017-01-26 11:54:57"
"3679","15","Exploiting analytical structure to develop accelerated numerical solutions in continuum modeling of materials","2017-04-19 16:30:00","2017-04-19 17:30:00","SAS 2229","Mansoor Haider","http://www4.ncsu.edu/~mahaider/","NC State",,,"In many modeling applications, the analytical structure of fundamental solutions to associated mathematical problems  can be exploited to develop more efficient or robust numerical algorithms.  I will present several examples of such approaches and techniques based on integral representations arising in the continuum modeling of materials.  Some techniques to be discussed include asymptotic analysis, exploiting separability, boundary integral equations and the fast multipole method.","jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/re1fn8dd15fl68qjdjoodv2nt8","2016-12-19 10:40:13","2017-04-05 16:46:25"
"3681","4","Swarming, Interaction Energies and PDEs","2017-01-11 15:00:00","2017-01-11 16:00:00","SAS 4201","J.A.Carrillo","http://wwwf.imperial.ac.uk/~jcarrill","Imperial College London",,,"I will present a survey of the main results about first and second order models of swarming where repulsion and attraction are modeled through pairwise potentials. We will mainly focus on the stability of the fascinating patterns that you get by random particle simulations, flocks and mills, and their qualitative behavior. Qualitative properties of local minimizers of the interaction energies arecrucial in order to understand these complex behaviors. Compactly supported global minimizers determine the flock patterns whose existence is related to the classical H-stability in statistical mechanics and the classical obstacle problem for differential operators.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8dc0qrvq5lmrbbf881fea6l8bk","2016-12-20 12:36:37","2016-12-30 11:45:35"
"3682","19","First Meeting","2017-01-11 15:00:00","2017-01-11 16:00:00","SAS 2102",,,,,,"We will meet briefly to sign up for talks for the semester.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mdt8plvkke2k8tsk221uts10h4","2016-12-20 16:50:18",NULL
"3683","3","Canonical bases, subalgebras, reductive pairs of Lie algebras, and possible applications","2017-02-06 15:00:00","2017-02-06 16:00:00","SAS 4201","Uladzimir Shtukar",,"NC Central University",,,"Subalgebras of Lie algebra of Lorentz group will be discussed as the basic examples at the beginning of the report. The corresponding analysis is performed by canonical bases for subspaces of a vector space. All canonical bases for 5-dimensional and 4-dimensional subspaces of a 6-dimensional vector space are found, and they are utilized to find the corresponding subalgebras of 6-dimensional Lie algebra of Lorentz group.

The examples will show that each canonical basis is associated with matrix in reduced row echelon form. This relation allows us to generalize previous results, and canonical bases for (n-1)-dimensional subspaces and for (n-2)-dimensional subspaces of n-dimensional vector space will be found. Meanwhile all reduced row echelon forms of   matrices and   matrices will be classified also.

Prospective applications for canonical bases will be described as the final part of the report.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/q8qb9qa26jctkj2sh8r4imja3o","2017-01-02 09:55:24","2017-01-07 16:54:43"
"3684","14","Spring  Departmental Meeting","2017-01-12 16:00:00","2017-01-12 17:15:00","SAS 1102",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/ivmlf3f746fv32m114f27np10k","2017-01-05 11:37:39",NULL
"3685","14","Spring  Departmental Meeting Reception","2017-01-12 15:30:00","2017-01-12 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/f7to0ea6o0quaaigm8fvuu7k50","2017-01-05 11:38:14",NULL
"3686","28","Weekly Brown Bag Lunch","2017-01-11 12:00:00","2017-01-11 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/s5uej5njpas3s5th1u0cpla140","2017-01-08 13:48:11",NULL
"3687","28","Weekly Brown Bag Lunch","2017-01-18 12:00:00","2017-01-18 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/8l70f10dep8ros34l91lisdalk","2017-01-08 13:49:38",NULL
"3688","28","Weekly Brown Bag Lunch","2017-01-25 12:00:00","2017-01-25 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/nfubq28ijc530ggmfo0uok7e3g","2017-01-08 13:50:26",NULL
"3689","28","Weekly Brown Bag Lunch","2017-02-01 12:00:00","2017-02-01 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/rmf6up0ar9rq0jg5lo8lh82r7c","2017-01-08 13:51:09",NULL
"3690","28","Weekly Brown Bag Lunch","2017-02-08 12:00:00","2017-02-08 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/j63359pm7t2f0ahhp6abu5g0sg","2017-01-08 13:51:54",NULL
"3691","28","Weekly Brown Bag Lunch","2017-02-15 12:00:00","2017-02-15 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/7bo4nl8o4emv07tkfnsv1d9bb0","2017-01-08 13:52:38",NULL
"3692","28","Weekly Brown Bag Lunch","2017-02-22 12:00:00","2017-02-22 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/c2vd21krl82id3vu8o7394bef8","2017-01-08 13:53:56",NULL
"3693","28","Weekly Brown Bag Lunch","2017-03-01 12:00:00","2017-03-01 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/uecfmnhe00fcf8j4c3io1rqp0k","2017-01-08 13:55:17",NULL
"3694","28","Weekly Brown Bag Lunch","2017-03-15 12:00:00","2017-03-15 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6va2o55t78bj1jh07riqcb33oc","2017-01-08 13:56:14",NULL
"3695","28","Weekly Brown Bag Lunch","2017-03-22 12:00:00","2017-03-22 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/je78a0u861mhjf25pkmp2fq85g","2017-01-08 13:57:14",NULL
"3696","28","Weekly Brown Bag Lunch","2017-03-29 12:00:00","2017-03-29 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6ba61v6s0a2a2ib58hu4n2hafs","2017-01-08 13:58:06",NULL
"3697","28","Strategies for Navigating Gender Bias Discussion","2017-04-05 12:00:00","2017-04-05 13:30:00","SAS 4201",,,,,,"On behalf of a project run by The Graduate School, AWM will facilitate a discussion among female graduate students about strategies for navigating gender bias in academia. AWM will provide bagels and other treats to participants. This is meant to be a casual conversation, and nothing will be recorded. We will share your stories with the Graduate School (possibly in modified form so that your identity is not revealed) only if you allow us to do so.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/00akbe71npiubj6h50ce5fhk54","2017-01-08 13:58:53","2017-03-26 17:51:04"
"3698","28","Weekly Brown Bag Lunch","2017-04-12 12:00:00","2017-04-12 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/kqm7v6skqvpl1cskrddru3rp9o","2017-01-08 13:59:56",NULL
"3699","28","Weekly Brown Bag Lunch","2017-04-19 12:00:00","2017-04-19 13:00:00","SAS 4104",,,,,,"Please join us for our weekly brown bag lunch! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/f9kmr817f5qsbja5dqpauvh3ac","2017-01-08 14:00:34",NULL
"3700","28","Weekly Brown Bag Lunch","2017-04-26 12:00:00","2017-04-26 13:00:00","SAS 4104",,,,,,"Please join us for our last weekly brown bag lunch of the year! You bring your lunch, and we will bring a delicious treat. Everyone (not just women) is welcome to join or stop by for as long as they can!","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/2d4t0n56o9n2mjqjrguu4ch6s0","2017-01-08 14:01:46",NULL
"3701","14","Departmental Tea and Cookies","2017-01-11 14:30:00","2017-01-11 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4mk8ulvra994pje6icuoc7agr8","2017-01-10 13:30:30",NULL
"3702","9","Understanding plant hormone signaling through the synergy of computational and synthetic biology","2017-01-17 10:00:00","2017-01-17 11:00:00","Thomas Hall 3503  ","Krzysztof Wabnik","http://profiles.ucsd.edu/krzysztof.wabnik","BioCircuits Institute, University of California, San Diego",,,"This seminar is for the Chancellors Faculty Excellence Program: Quantitative and Computational Developmental Biology Cluster Hire.

Refreshments will be served at 9:45 a.m.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/phsc9fu66iujg77p8pmbpnjnv8","2017-01-11 10:32:12","2017-01-11 14:11:30"
"3703","2","Control and Numerics: Recent Progress and Challenges","2017-01-17 15:00:00","2017-01-17 16:00:00","SAS 4201","Enrique Zuazua","http://verso.mat.uam.es/web/ezuazua/zuazua.html","DeustoTechBilbao & Universidad Autnoma de Madrid, Spain","ralph smith",,"In most real life applications Mathematics not only face the challenge of modeling (typically by means of ODE and/or PDE), analysis and computer simulations but also the need control and design.
 
And the successful development of the needed computational tools for control and design cannot be achieved by simply superposing the state of the art on Mathematical and Numerical Analysis. Rather, it requires specific tools, adapted to the very features of the problems under consideration, since stable numerical methods for the forward resolution of a given model, do not necessarily lead to stable solvers of control and design problems.
           
In this lecture we will summarize some of the recent work developed in our group, motivated by different applications, that have led to different analytical and numerical methodologies to circumvent these difficulties.
 
The examples we shall consider are motivated by problems of different nature and lead to various new mathematical developments. We shall mainly focus on the following three topics:
1. Inverse design for sonic boom minimization: the turnpike property,
2. Actuator location for noise reduction: randomization and averaging,
3. Collective behavior: guidance by repulsion.
 
We shall also briefly discuss the convenience of using greedy algorithms when facing parameter-dependence problems.

Biosketch:
(Eibar, Basque Country  Spain, 1961) is the&amp;#8232; Director of the Chair in Computational Mathematics at&amp;#8232; DeustoTech Laboratory in the University of Deusto, Bilbao&amp;#8232; (Basque Country-Spain) where he leads the research team&amp;#8232; funded by the European Research Council Advanced Grant&amp;#8232;DYCON: Dynamic Control. He is also a Professor of the&amp;#8232; Department of Mathematics of Universidad Autnoma de Madrid  UAM where he holds a Strategic Chair in Applied Mathematics since 2001. 

His fields of expertise in the area of Applied Mathematics cover topics related with Partial Differential Equations, Systems Control and Numerical Analysis. His work in the interface between Control Systems Theory and Numerical Analysis and Scientific Computing has led to some fruitful collaboration with different industrial sectors such as the optimal shape design in aeronautics and the management of electrical and water distribution networks. 

He holds a degree in mathematics from the University of the Basque Country, and a dual PhD degree from the same university (1987) and the &quot;Universit Pierre et Marie Curie&quot;, Paris (1988). In 1990 he became Professor of Applied Mathematics at the Universidad Complutense de Madrid, to later move to UAM in 2001. 

He has been awarded the Euskadi (Basque Country) Prize for Science and Technology 2006 and the National Julio Rey Pastor Prize 2007 in Mathematics and Information and Communication Technology and the Advanced Grants of the European research Council (ERC) NUMERIWAVES in 2010 and DYCON in 2016. 

He is an Honorary member of the of Academia Europaea and Jakiunde, the Basque Academy of Sciences, Letters and Humanities, Visiting Professor of the Laboratoire Jacques-Louis Lions of the Universit Pierre et Marie Curie in Paris and Sichuan University in Chengdu China and Doctor Honoris Causa from the Universit de Lorraine in France, France, Member and Ambassador of the Friedrisch Alexandre University in ErlangenNurenberg, Germany. 

From 1999-2002 he was the first Scientific Manager of the Panel for Mathematics within the Spanish National Research Plan. From 20082012 he was the Founding Scientific Director of the BCAM  Basque Center for Applied Mathematics, where he was the leader of the research group on PDE, Control and Numerics, until 2015, in his condition of Distinguished Ikerbasque Professor. 

He is the editor-in-chief of the Journal Mathematical Control and Related Fields, the coordinatior of the BCAM  SpringerBriefs Series and member of the editorial committee of other Journals and of scientific committees of various centres and agencies.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/bp034ekk63mrl942dbe3n0pocc","2017-01-11 14:12:45","2017-01-17 11:37:15"
"3704","8","Gaussian Mixtures and their Tensors","2017-03-28 15:30:00","2017-03-28 16:30:00","SAS 4201","Bernd Sturmfels","https://math.berkeley.edu/~bernd/","UC Berkeley",,,"Mixtures of Gaussians are ubiquitous in data science. We give an introduction to the geometry of these statistical models, with focus on the tensors that represent their higher moments. The familiar theory of rank and borderrank for symmetric tensors is recovered when all covariance matrices are zero. Recent work with Carlos Amendola and Kristian Ranestad characterizes the circumstances under which Gaussian mixtures are identifiable from their moments.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/hq6aq0arjf5if1eibm8ggps25g","2017-01-11 16:49:26","2017-03-13 17:52:22"
"3705","4","Vanishing viscosity solutions for Riemann problems in polymer flooding","2017-03-29 15:00:00","2017-03-29 16:00:00","4201","Wen Shen","http://www.math.psu.edu/shen_w/","Penn State University","Khai Nguyen",,"We visit several models of polymer flooding in reservoir simulation.
A special common feature shared by the models, i.e., the thermo-dynamics is decoupled from the hydro-dynamics, leads to a scalar conservation law with discontinuous flux. We discuss solution of Riemann problems as the vanishing  viscosity limit. In particular,  we show by counter examples that there exists infinitely many vanishing viscosity solution as one varies the ratio of the two viscosity parameters. However, adding two monotonicity conditions, all double limits will converge to the same function.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/rlelcbll29b4lheqc74aa2map8","2017-01-12 15:17:35","2017-02-13 09:31:21"
"3706","46","Moving Frames in Mechanics","2017-01-25 16:00:00","2017-01-25 17:00:00","SAS 4201","Dmitry Zenkov","http://www4.ncsu.edu/~dvzenkov/",,"Irina Kogan",,"The history of the use of moving frames in mechanics is more than 250 years long. The key steps were carried out by Euler, Poincar, Hamel, and recently Marsden in relation to the dynamics and stability of rigid body, fluid, and complex interconnected mechanical systems. The talk will review some of this history and discuss recent development of these ideas for infinite-dimensional mechanical systems.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3co4am4o6mtvvsekik8qk1n6h0","2017-01-13 14:57:04","2017-01-19 18:16:02"
"3707","38","Conjugacy and other results in Leibniz algebras - advised by Ernie Stitzinger","2017-02-10 10:30:00","2017-02-10 12:30:00","SAS 3282","Ashley White",,"NC State Mathematics Graduate Student","Ernie Stitzinger",,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/7h622ja3jrgqde1ksg2df9os9k","2017-01-13 15:29:33","2017-01-17 12:44:43"
"3708","22","Fractals, the Chaos Game, and the Contraction Mapping Theorem","2017-01-19 16:30:00","2017-01-19 17:20:00","SAS 2102","Nathan Reading","http://www4.ncsu.edu/~nreadin/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/011917.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/561a25pmn9qok8npcorte6njh4","2017-01-13 16:42:41",NULL
"3709","14","Departmental Tea and Cookies","2017-01-17 14:30:00","2017-01-17 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/me5elpsvkjp8brr7a8806g5vn0","2017-01-17 10:01:58",NULL
"3710","2","Geometric Numerical Integration and Computational Geometric Mechanics","2017-01-23 16:00:00","2017-01-23 17:00:00","SAS 4201","Melvin Leok","http://math.ucsd.edu/~mleok/","University of California, San Diego","ralph smith",,"Symmetry, and the study of invariant and equivariant objects, is a deep and unifying principle underlying a variety of mathematical fields. Geometric mechanics is characterized by the application of symmetry and differential geometric techniques to Lagrangian and Hamiltonian mechanics, and geometric integration is concerned with the construction of numerical methods with geometric invariant and equivariant properties. Computational geometric mechanics blends these fields, and uses a self-consistent discretization of geometry and mechanics to systematically construct geometric structure-preserving numerical schemes.

In this talk, we will introduce a systematic method of constructing geometric integrators based on a discrete Hamiltons variational principle. This involves the construction of discrete Lagrangians that approximate Jacobis solution to the Hamilton-Jacobi equation. Equivariant approximation spaces are important in the construction of geometric integrators that conserve multimomentum, and we will describe a general construction for group-equivariant interpolants on symmetric spaces with applications to Lorentzian metrics.

Biosketch: Melvin Leok is a full professor in the Department of Mathematics at the University of California, San Diego. His research interests are in computational geometric mechanics, computational geometric control theory, discrete geometry, and structure-preserving numerical schemes. He received his Ph.D. in 2004 from Caltech in Control and Dynamical Systems under the direction of Jerrold Marsden. He is a three-time NAS Kavli Frontiers of Science Fellow, and has received the NSF CAREER award, SciCADE New Talent Prize, SIAM Student Paper Prize, and the Leslie Fox Prize (second prize) in Numerical Analysis. He serves on the editorial boards of the Journal of Nonlinear Science, the SIAM Journal on Control and Optimization, the LMS Journal of Computation and Mathematics, the Journal of Geometric Mechanics, and the Journal of Computational Dynamics.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/d33s3f38iufgtth930qdpurdcc","2017-01-17 10:54:59","2017-01-18 12:14:07"
"3711","14","Departmental Tea and Cookies","2017-01-23 15:30:00","2017-01-23 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/1840u5ljhlshrspo91ibeu698o","2017-01-17 10:56:34",NULL
"3712","14","Departmental Tea and Cookies","2017-02-02 15:30:00","2017-02-02 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/g585jo7sndc190mru4p1be11ug","2017-01-17 10:57:06",NULL
"3713","9","Bayesian Filtering for Time-Varying Parameter Estimation in Biological Models","2017-01-19 16:20:00","2017-01-19 17:20:00","Cox 306","Andrea Arnold",,"NC State",,,"Many applications in the life sciences involve unknown system parameters that must be estimated using little to no prior information.  In addition, these parameters may be time-varying and possibly subject to structural characteristics such as periodicity.  We show how nonlinear Bayesian filtering techniques can be employed in this setting to estimate unknown, time-varying parameters, while naturally providing a measure of uncertainty in the estimation.  Results are demonstrated with real data from several biological applications, including cardiovascular dynamics and the modeling of infectious diseases.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/3kcr34miu1stbomhrq193h67ac","2017-01-17 12:25:00",NULL
"3714","3","Euler-Maclaurin Summation Formulas for Polytopes","2017-02-20 15:00:00","2017-02-20 16:00:00","SAS 4201","Jamie Pommersheim","http://people.reed.edu/~jamie/","Reed College",,,"Discovered in the 1730s, the classical Euler-Maclaurin formula may be viewed as a formula for summing the values of a function over the lattice points in a one-dimensional polytope.  Several years ago, Berline and Vergne generalized this formula to polytopes of arbitrary dimension, obtaining a formula for the sum of a polynomial function over the lattice points in any rational polytope. This talk will present an algebraic approach to the Euler-Maclarurin problem for polytopes based on recent results of Fischer and the speaker. While this approach is motivated from the theory of toric varieties, in this talk we aim to tell the story in a way that does not directly use results from toric geometry.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/nud2rn756748oj7opeahmt2uu0","2017-01-17 13:03:58","2017-02-10 16:20:56"
"3716","19","Tropical geometry for matrix completion and combinatorial properties of hierarchical models","2017-02-01 15:00:00","2017-02-01 16:00:00","SAS 2102","Daniel Bernstein ",,,,,"This is a practice run of my prelim talk. It will be broken into two disjoint parts.

The first part is motivated by the problem: given a matrix of low rank where only some of the entires are known, is it possible to reconstruct the missing entries? I will show how tropical geometry can be used to obtain theoretical results related to this problem.

The second part is about the following. A high-dimensional table can be summarized by a collection of its lower-dimensional marginals (these are generalizations of the row and column sums of a matrix). A collection of marginals can be described by a simplicial complex. I will discuss how the combinatorics of this simplicial complex can be used to answer questions about the geometry that underlies the integer feasibility problem.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4304lhkbd9nv4ooloqdtqta7t0","2017-01-17 17:24:04","2017-01-27 11:11:42"
"3717","19","Geometry and polynomial invariants of a phylogenetic model","2017-02-08 15:00:00","2017-02-08 16:00:00","SAS 2102","Christopher Durden",,,,,"I will discuss whether it is possible to reconstruct a phylogenetic tree from sequence data, given a specific model of evolution. To answer this question for a coalescent-based model, we study ideals associated to the model. By observing some facts about the geometry of the model, we can demonstrate that these ideals contain polynomials which may be used to determine the underlying tree.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/daudg2gsj7ae4kpli20dqg7e6g","2017-01-17 17:25:21","2017-02-05 16:18:52"
"3718","46","Non-standard bridge trisections of the unknotted 2-sphere in the 4-space","2017-04-24 16:00:00","2017-04-24 17:00:00","SAS 1102","Alex Zupan",,"University of Nebraska Lincoln","Tye Lidman",,"very knotted surface in 4-space has a bridge trisection, a decomposition into three simple pieces.  Bridge trisections yield diagrams that reduce the 4-dimensional object to 3-dimensional data, which can be manipulated just like classical knot diagrams.  A first step in understanding the structure of such decompositions is to classify splittings of the unknot -- one dimension lower, Otal proved that every non-minimal bridge decomposition of the unknot in 3-space can be simplified in a generic way.  We prove that the same result does not hold for bridge trisections of the unknotted 2-sphere.  This is joint work with Jeffrey Meier.","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4n4efdkei87lm4irkrc7kj9neo","2017-01-17 19:42:53","2017-04-17 18:30:52"
"3719","22","Dots, Squiggles, and a Shocking Twist!","2017-01-26 16:30:00","2017-01-26 17:20:00","SAS 2102","Emily Barnard","https://emilybarnard.wordpress.ncsu.edu/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/012617.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/41i7kmn46lrmgoiq54dolr644s","2017-01-18 10:03:33","2017-01-20 10:26:13"
"3720","22","The problem with birthdays","2017-02-09 16:30:00","2017-02-09 17:20:00","SAS 2102","Seth Sullivant","http://www4.ncsu.edu/~smsulli2/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/020917.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/g2r4f0l50kenc17nnettrb66vk","2017-01-18 10:05:10","2017-01-18 10:28:43"
"3721","4","Global reconstruction methods for nonlinear inverse scattering problems","2017-02-01 15:00:00","2017-02-01 16:00:00","SAS 4201","Dinh-Liem Nguyen","https://sites.google.com/site/dinhliemnguyen/","UNC Charlotte","Khai Nguyen",,"This talk is about numerical methods for solving inverse problems arising from wave scattering. Potential applications of these problems include non-destructive testing, detection of explosives, medical imaging, geophysical prospection and radar. The major challenges in studying the numerical solution to these inverse problems are from the fact that the problems are highly nonlinear and ill-posed. The most developed approach in literature, which is nonlinear optimization schemes, typically requires good initial guesses for the solution since the objective functionals to minimize are in general not convex. However, such good initial guesses (or strong a-priori information of the solution) are not always available in many practical applications. The latter is the main reason for us to study global reconstruction methods, which do not rely on strong a-priori information of the solution, for nonlinear inverse problems. I will present in this talk my recent results for two kinds of global reconstruction methods. This first one aims to solve a coefficient inverse problem with single measurement and the second one is for a shape inverse problem for periodic structures.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/m8kqdecneb5kqrr4dhde7t98ic","2017-01-18 10:12:42","2017-01-18 10:14:13"
"3722","22","Map colorings (of no particular interest to mapmakers)","2017-02-02 16:30:00","2017-02-02 17:20:00","SAS 2102","Radmila Sazdanovic","http://www4.ncsu.edu/~rsazdan/index.html",,,"https://web.math.ncsu.edu/sumseries/spring2017/020217.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/s0nst62lku21kmtu8fbprk4g6g","2017-01-18 10:27:36","2017-01-26 10:45:52"
"3723","34","Natural history of life history traits and the post-K-Pg nocturnal bottleneck of Placentals","2017-02-03 13:30:00","2017-02-03 14:30:00","Ricks 336","Jiaqi Wu",,"University of Tokyo",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/m4tcts3udko9ufm8ism1cnergs","2017-01-18 13:06:24",NULL
"3724","2","What are Math Circles and why to participate?","2017-02-03 14:00:00","2017-02-03 15:00:00","SAS 2106","Tatiana Shubin","http://www.sjsu.edu/math/people/faculty/shubin/","San Jose State University","Irina Kogan",,"Tatiana Shubin will share her experience of organizing Math Circles in the Bay Area and in Navajo Indian Reservation.","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/e2gsr90rrqk8ol18nho4lrstuo","2017-01-19 18:32:08","2017-01-19 18:38:07"
"3725","46","The Andrews-Curtis Conjecture and new handle decompositions of the 4-sphere","2017-04-25 15:00:00","2017-04-25 16:00:00","SAS 1102","Alex Zupan",,"University of Nebraska Lincoln","Tye Lidman",,"The Andrews-Curtis Conjecture, proposed in the 1960s, asserts that every balanced presentation of the trivial group can be simplified with a set of moves, called Andrew-Curtis moves.  Every handle decomposition of the 4-sphere with no 3-handles induces such a presentation, with handle-slides corresponding to Andrews-Curtis moves.  The most prominent examples in this setting are due to Gompf-Scharlemann-Thompson, building off work of Akbulut-Kirby.  We describe a new construction that generalizes the work of Gompf-Scharlemann-Thompson, with intriguing connections to the Andrews-Curtis Conjecture.  This is joint work in progress with Jeffrey Meier.","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/80ng28s3e69llcvdpl9fmncca4","2017-01-21 10:51:51","2017-04-17 18:31:29"
"3727","46","TBA (Graduate student talk)","2017-02-21 15:00:00","2017-02-21 16:00:00","SAS 1102","Peter Lambert-Cole",,"Indiana University","Tye Lidman",,"TBA","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9qnf6o341ufj335ag8gi53jo8k","2017-01-21 11:02:15",NULL
"3728","46","Conway mutation and knot Floer homology","2017-02-21 16:15:00","2017-02-21 17:15:00","SAS 1102","Peter Lambert-Cole",,"Indiana University","Tye Lidman",,"Mutant knots are notoriously hard to distinguish. Many, but
not all, knot invariants take the same value on mutant pairs. Khovanov homology with coefficients in Z/2Z is known to be mutation-invariant, while the bigraded knot Floer homology groups can distinguish mutants such as the famous Kinoshita-Terasaka and Conway pair. However, Baldwin and Levine conjectured that delta-graded knot Floer homology, a singly-graded reduction of the full invariant, is preserved by mutation. In this talk, I will give a new proof that Khovanov homology mod 2 is mutation-invariant. The same strategy can be applied to delta-graded knot Floer homology and proves the Baldwin-Levine conjecture for mutations on a large class of tangles.","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/82i44n8nmk5kh0g8mudqlf9j78","2017-01-21 11:03:35","2017-02-15 00:28:13"
"3729","23","Joint Math Meeting survival guide","2017-01-27 15:00:00","2017-01-27 16:00:00","SAS 4201","Student panel   ",,,"Pierre Gremaud",,"A panel of graduate students will share their experience at the 2017 Joint Math Meeting regarding job interviews and presentations. 

Attendance is highly recommended to anyone susceptible to attend a job fair in the near (or not so near) future.","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/81vt1478jgp5qtqngmcnpef630","2017-01-23 17:20:37","2017-01-23 17:22:21"
"3730","24","MGSA Graduate Student Pizza Party","2017-01-26 12:00:00","2017-01-26 14:00:00","4th floor lounge in SAS",,,"MGSA",,,"Please join the MGSA for free pizza and drinks. We will be in the 4th floor lounge of SAS from 12:00-2:00. Feel free to stop by for a minute or stay the whole time.  All grad students are welcome.","mrgaddy","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/n28l6cfn5a1kf744igpg9tl6rg","2017-01-24 10:26:45",NULL
"3731","24","MGSA Valentines Day Cookie Contest","2017-02-14 12:00:00","2017-02-14 14:00:00","4th floor lounge of SAS",,,,,,"Please join MGSA as we celebrate Valentines Day with sweet treats.  To submit your cookies to the contest, please bring them to the fourth floor lounge of SAS before noon.  Then stop by between 12 and 2 to eat cookies and vote for your favorite!  MGSA will be providing coffee and milk.  All math faculty, staff, and grad students are invited.","mrgaddy","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/3hp6ngblr4v0rl8kb8skoq9ils","2017-01-24 10:31:26","2017-02-12 17:48:51"
"3732","6","A preconditioning method for dense linear systems","2017-03-06 15:00:00","2017-03-06 15:30:00","SAS 4201","Takeshi Ogita ",,"Tokyo Womans Christian University",,,"This talk is concerned with accurate numerical solutions of ill-conditioned dense linear systems. Recently, we have developed some preconditioning methods for this purpose. Using such preconditioned methods, the condition number of the coefficient matrices can be reduced sufficiently. However, computational cost for such a preconditioning is considerably larger than the standard numerical algorithm such as LU factorization, since high-precision matrix multiplication is required. In this talk, we modify this point by exploiting the structure of the coefficient matrix and develop an efficient algorithm for solving ill-conditioned linear systems in high accuracy. As a result, computational cost for preconditioning can be significantly reduced with similar quality to the previous methods. Numerical results are presented showing the performance of the algorithm.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8cmjmhh9auqcur24pitllpnv2k","2017-01-24 10:40:07","2017-03-03 10:15:22"
"3733","6","Reproducible summation, error-free transformations, and floating-point error estimates","2017-03-06 15:30:00","2017-03-06 16:00:00","SAS 4201","Siegfried M. Rump",,"Hamburg Technical University and Waseda University, Tokyo",,,"Recently, reproducible summation gained much interest. The main problem is the lack of associativity of floating-point addition. One possibility to attack the problem is to compute without error, for example using error-free transformations. Some algorithms to that end will be presented. In a second part we will show new and improved error estimates for floating-point summation. As a new result, we completely refrain from using some floating-point grid. In contrast, we treat perturbed real sums, i.e., each individual addition is somehow perturbed, where there is almost no restriction on the size or kind of the perturbations. Nevertheless, we can avoid higher order terms in the error estimates.","asaibab","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/oa1pea94cpi09fffev835if8ic","2017-01-24 10:41:42","2017-01-24 10:43:00"
"3734","38","Canonical join representation in algebraic combinatorics - advised by Nathan Reading","2017-03-24 14:00:00","2017-03-24 16:00:00","SAS 3282","Emily Barnard",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ndvmguu1pmpgltj7c47i1n86fo","2017-01-24 16:37:37","2017-01-24 16:40:13"
"3735","46","Understanding Integrability via Characteristic Varieties and their Secants","2017-02-15 16:00:00","2017-02-15 17:00:00","SAS 4201","Abraham Smith","http://www.curieux.us/abe/","University of WisconsinStout","Irina Kogan",,"This talk is a summary of an ongoing effort understand the phenomenon of Hydrodynamic Integrability from the intrinsic differential geometry of the Characteristic Variety. Hydrodynamic Integrability corresponds to superposition of solutions in wave-like equations. To study this phenomenon in a coordinate-invariant way, we re-phrase it as the existence of &quot;many&quot; hyper-surfaces in solutions.  This can, in turn, be expressed in terms of the geometry of the Characteristic Variety and its secants. New computational tools have been built recently that allow explicit exploration of these features of the characteristic variety. Ill conclude with a conjecture (being actively pursued by myself and several collaborators) about the structure of all hydrodynamically integrable PDEs in all dimensions.  This talk involves a mix of analysis, differential geometry, and algebraic geometry, and scientific programming, so theres something for everyone!","iakogan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/oqr200eun0lbbkhetcucechua0","2017-01-25 15:26:57","2017-02-07 13:58:08"
"3736","38","Lower bound for size of maximum gap in (inverse) cyclotomic polynomials - advised by Hoon Hong","2017-03-27 12:00:00","2017-03-27 14:00:00","SAS5270","Mary Ambrosino",,"NC State Mathematics Graduate Student",,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/6pdl7s8a1838gv51r83sp3julo","2017-01-26 11:53:02","2017-03-27 11:06:27"
"3737","46","Quantum Knot and Link Invariants from the Symmetric Perspective","2017-03-01 16:00:00","2017-03-01 17:00:00","SAS 4201","David Rose",,"UNC","Tye Lidman",,"The traditional graphical description of quantum polynomial invariants of knots and links (such as the Jones polynomial) relies on a diagrammatic presentation of the representation theory of quantum groups based on skew-symmetric tensors. We will discuss work (joint with D. Tubbenhauer) which gives a different construction of these knot and link invariants using the symmetric tensors. We will then investigate a  categorification of this description (joint work with H. Queffelec and A. Sartori) which produces homology theories for knots and links. Surprisingly, well see examples where the symmetric and skew-symmetric invariants agree at the decategorified level, but the homologies do not!","tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1gbcliquhnajqi3takeq4mdqkc","2017-01-26 22:29:30","2017-02-21 18:14:46"
"3738","2","The Role of Sensors and Actuators in Control of Infinite-Dimensional Systems","2017-02-02 16:00:00","2017-02-02 17:00:00","SAS 4201","Kirsten Morris","https://uwaterloo.ca/applied-mathematics/people-profiles/kirsten-morris",,,,"For systems modeled by partial differential equations, there is generally choice in the type of actuator and sensors used and also their locations.  Several examples are given to illustrate how choice and modeling of the actuators and sensors affects control system performance.  Once the control hardware, the actuators and sensors, are selected, performance depends not only on the controller, but also on the location of the hardware. Physical intuition does not always lead to the best choice of locations. Since it is often difficult to move hardware, and trial-and-error may not be effective when there are multiple sensors and actuators, analysis is crucial.  Integrating controller design with actuator location can lead to better performance without increased controller cost. Similarly, better estimation can be obtained with carefully placed sensors.  Proper placement when there are disturbances present is in general different from that appropriate for reducing the response to an initial condition, and both are different from locations based on optimizing controllability or observability.  Approximations to the governing equations, often of very high order, are required and this complicates both controller design and optimization of the hardware locations.  

Biosketch: Prof. Kirsten Morris research interests are systems modelled by partial differential equations and also systems, such as smart materials, involving hysteresis.  She has  written an undergraduate textbook &quot;Introduction to Feedback Control&quot;, and was editor of the book  Control of Flexible Structures.  She is a professor in the Applied Mathematics Department at that University  with a cross-appointment to the Department of Mechanical &amp; Mechatronics Engineering. From 2005-2008 she was Associate Dean for Graduate Studies &amp; Research in the  Faculty of Mathematics.  Prof. Morris  served as a vice-president of  the  IEEE Control System Society from 2013-2016. She was an associate editor with the IEEE Transactions on Automatic Control  and is currently SIAM Journal on Control &amp; Optimization, as well as Mathematics of Control, Signals and Systems and is a member of the editorial board of the  SIAM  book series Advances in Design &amp; Control.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jc008i6r6gt9clrh1kt8qi8tv4","2017-01-28 16:46:13","2017-01-28 16:47:54"
"3739","46","Dehn surgery obstructions","2017-02-01 16:00:00","2017-02-01 17:00:00","SAS 4201","Tye Lidman",,"NC State",,,,"tlidman","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ic0glekr7e4as0b3b0k5co6q7c","2017-01-29 10:20:33","2017-01-29 10:27:51"
"3740","38","Posets and Hopf algebras of rectangulations - advised by Nathan Reading","2017-03-15 12:30:00","2017-03-15 14:30:00","SAS 3282","Emily Meehan",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ab5scagvo3l24rhq9p9jpqsmtc","2017-01-30 09:30:16","2017-01-30 09:31:33"
"3741","8","Computing Real Equilibria of the Kuramoto Model","2017-02-21 15:30:00","2017-02-21 16:30:00","SAS 4201","Owen Coss",,"NCSU",,,"The Kuramoto model is used to describe synchronization behavior of a large set of oscillators. The equilibria of this model can be computed by solving a system of polynomial equations using algebraic geometry. Typical methods for solving such polynomial systems compute all complex equilibrium points when only the real equilibrium points are of physical interest, and are very slow. We developed an approach to compute only the real equilibrium points. This approach allows for a much more efficient solving algorithm and offers insight into the maximum number of real equilibria.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/obdaassobedt6fpdvc4gnb7ccs","2017-01-30 22:57:03","2017-02-20 11:28:43"
"3742","26","Methods for modeling cell proliferation and differentiation patterns in the neurogenesis-to-gliogenesis switch","2017-02-06 16:00:00","2017-02-06 17:00:00","SAS 4201","Christine Mennicke",,"NC State",,,"Radial glial progenitors follow patterns of proliferation and differentiation to produce neurons and glia in the developing brain. The cells first undergo neurogenesis, producing neurons in a fairly deterministic manner, and then a portion of the cell population switches to producing glia. This neurogenesis-to-gliogenesis switch (NGS) and the patterns of cell division in gliogenesis are not yet undestood to be deterministic or stochastic. I will discuss methods from papers that have explored cell division patterns, then explain how these methods can be used to analyze to data we have from the NGS. Additionally, I will examine different approaches for creating cell division models.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/v60s0d64honbdpfc62lraio93k","2017-02-03 10:58:13","2017-02-06 11:22:23"
"3743","19","Determinantal Representations of Hyperbolic Plane Curves with Dihedral Invariance","2017-02-15 15:00:00","2017-02-15 16:00:00","SAS 2102","Faye Pasley",,,,,"Given a determinantal representation by means of a cyclic weighted shift matrix, one can show the resulting polynomial is hyperbolic and invariant under the action of the dihedral group. Chien and Nakazato (2015) asked the converse question. By properly modifying a determinantal representation construction of Dixon (1902), we show for every hyperbolic polynomial with dihedral invariance there exists a determinantal representation admitted via some cyclic weighted shift matrix with real entries.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n3t3ag1t1erd533d44rqitr73s","2017-02-05 16:20:46","2017-02-13 10:57:27"
"3744","4","Stability of Degenerately Damped Vibration","2017-03-15 15:00:00","2017-03-15 16:00:00","SAS 4201","Daniel Toundykov",,"University of Nebraska Lincoln","Lorena Bociu",,"I will discuss some theoretical and numerical results on the stability properties of a dynamical system modeled by a nonlinear wave equation with a &quot;degenerate&quot; damping. The coefficient of the dissipation term is proportional to the amplitudes, hence its support depends on the geometry of the solution. This feature substantially complicates the stability analysis even in a one-dimensional setting. Helpful insights, however, can be gleaned from numerical simulations.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/bjmglbkariu3si448aprguj6n8","2017-02-06 11:50:42","2017-02-27 09:27:25"
"3745","38","Using multi-class machine learning methods to predict major league baseball pitches - Advised by Hien Tran","2017-02-21 10:00:00","2017-02-21 12:00:00","SAS 4201","Glenn Sidle",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ru0406pavdocuhvdrj12c3dh4k","2017-02-08 10:15:16",NULL
"3746","22","Multiplication: how hard can it be?","2017-02-16 16:30:00","2017-02-16 17:20:00","SAS 2012","Cynthia Vinzant","http://www4.ncsu.edu/~clvinzan/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/021617.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mtf2qamoqebp64cr0oancdlavo","2017-02-10 10:03:30",NULL
"3747","22","On billiards and pi","2017-03-16 16:30:00","2017-03-16 17:20:00","SAS 2102","Ricky Liu","http://www4.ncsu.edu/~riliu/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/031617.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/1i15h6phq9qkumvnaerrhe77e0","2017-02-10 10:05:28","2017-03-13 10:07:00"
"3748","22","Who\'s in Control Here?","2017-03-23 16:30:00","2017-03-23 17:20:00","SAS 2102","Steve Campbell","http://www4.ncsu.edu/~slc/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/032317.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jfbrvj745o2m27t3afshh0lkv8","2017-02-10 10:06:48","2017-03-23 08:09:47"
"3749","22","Honors Research Presentations","2017-04-27 16:30:00","2017-04-27 17:20:00","SAS 2102","Beverly Setzer, Samuel Weber and Christopher Cardullo",,"NC State Undergraduate Students",,,"1. Beverly Setzer

Title: Detecting Hidden Nodes in Neuronal Networks using Adaptive Filtering

Abstract: The identification of network connectivity from noisy time series is of great interest in the study of network dynamics. This connectivity estimation problem becomes more complicated when we consider the possibility of hidden nodes within the network. These hidden nodes act as unknown drivers on our network and their presence can lead to the identification of false connections, resulting in incorrect network inference. Detecting the parts of the network they are acting on is thus critical. Here we propose a novel
method for hidden node detection based on an adaptive filtering framework with specific application to neuronal networks. We consider the hidden node as a problem of missing variables when model fitting, and show that the estimated system noise covariance
provided by the adaptive filter can be used to localize the influence of the hidden nodes and distinguish the effects of different hidden nodes. Additionally, we show that the sequential nature of our algorithm allows for tracking changes in the hidden node
influence over time. (Faculty mentor: F. Hamilton and Dr. A. Lloyd.)


2. Samuel Weber

Title:  Parallelization of the Metropolis-Hastings Algorithm for Large Scale Applications

Abstract: The Metropolis algorithm is often used when employing Markov chain Monte Carlo (MCMC) methods to obtain a sequence of random samples from a posterior probability distribution when direct sampling is unfeasible. It can be used to infer parameter uncertainties and correlation for subsequent uncertainty propagation. The Metropolis algorithm is advantageous when sampling from correlated multi-dimensional distributions. In its classical formulation, the algorithm runs chains serially, thus it must be run many times to establish convergence. However, it is possible to spawn multiple chains and simultaneously run them on multiple threads of a computer or graphics processing unit. This talk will feature changes made to the algorithm to allow for parallelization and the implications these changes can mean for parameter info-space and subsequent uncertainty quantifications. (Faculty mentor: Dr. R. Smith.)


3. Christopher Cardullo

Title: Change of Variables for Integrals of Densities on Superspace

Abstract: In this paper, we expand on the proof for the change of variables for integrals of densities as described by D. A. Leites. We extend his proof for H^&amp;#8734; densities to G^&amp;#8734; densities. We do this by using the construction of the supernumbers given by Rogers, as well as properties of G^&amp;#8734; functions that she has proven. (Faculty Mentor: Dr. R. Fulp.)","spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sofcvnv5c1ggquivnh21o0uvjg","2017-02-10 10:07:35","2017-04-26 10:07:26"
"3750","6","Randomized Sparse Kaczmarz Methods","2017-03-14 15:00:00","2017-03-14 16:00:00","SAS 4201","Dirk Lorenz","https://www.tu-braunschweig.de/iaa/personal/lorenz","TU Braunschweig","David Papp",,"The Kaczmarz method is a numerical method to solve systems of linear equations and compute minimum-norm solutions of underdetermined systems. Because the method has very low memory requirements it has gained new attention in recent years.

In this talk we propose a flexible algorithmic framework that extends the Kaczmarz method such that it also can handle, among other things, sparse solutions of underdetermined systems. The framework also includes other known methods such as the linearized Bregman iteration and can be extended to compute solutions of minimal total variation methods. The analysis is build on the notion of split feasibility problems. Furthermore, we show that randomization of the method allows to prove linear convergence of the method.

The algorithmic framework has a variety of applications and is especially useful for problems in which the linear measurements are slow and expensive to obtain. We present examples for online compressed sensing, TV tomographic reconstruction and radio interferometry.","dpapp","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jieotivi7bg7k3aaetb9upj1eg","2017-02-10 14:33:38","2017-03-07 13:01:28"
"3751","8","Sparse interpolation, Pade approximation, signal processing, and tensor decomposition","2017-04-11 15:30:00","2017-04-11 16:30:00","SAS 2102","Wen-shin Lee","http://win.ua.ac.be/~wlee/","University of Antwerp",,,"A mathematical model is called sparse if it is a combination of only a few non-zero terms. The aim of sparse interpolation is to determine both the support of the sparse linear combination and the coefficients in the representation, from a small or minimal amount of data samples. This talk centers around multi-exponential models: A common underlying problem statement in many applications is that of determining the number of exponential components, and for each component the value of the frequency, damping factor, amplitude and phase. It occurs, for instance, transient detection, motor fault diagnosis, electrophysiology, magnetic resonance spectroscopy, vibration analysis, fluorescence lifetime imaging, music signal processing, direction of arrival estimation in wireless communication systems, and so on.  In this talk, we describe sparse interpolation. We focus on the connections between sparse interpolation, structured matrices, generalized eigenvalue computation, exponential analysis, and rational approximation. In the past few years, insight gained from the computer algebra community combined with methods developed by the numerical analysis community, has led to significant progress in several very practical and real-life signal processing applications. We make use of tools such as the singular value decomposition and various convergence results for Pade approximants to regularize an otherwise inverse problem. Classical resolution limitations in signal processing with respect to frequency and decay rates, are overcome. The connection with tensor decomposition leads to new possibilities to exploit sparsity in analyzing tensor-structured datasets.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fbs6cdugish1cn3sffak2m5054","2017-02-10 14:53:13","2017-04-11 13:21:40"
"3752","9","Dynamics of dopamine neuron firing in normal and drug-modulated conditions","2017-02-21 16:20:00","2017-02-21 17:20:00","Cox 306","Boris Gutkin",,"Group for Neural Theory, Ecole Normale Superieure, Paris, France Center for Cognition and Decision Making, Higher School of Economics, Moscow, Russia","Alun Lloyd",,"Dopaminergic neurons in the ventral tegmental area play a key role in signalling motivational information.  Modulation of this signalling by drugs is also key to the development of addiction. These neurons have several firing modes ranging from periodic low frequency activity to higher frequency bursts. In vitro, intrinsically generated bursts are seen, while in vivo irregular high frequency alternates with periodic activity. Addictive drugs alter this firing patter towards high frequency bursting. In this talk i will discuss analysis of the mechanisms that lead to the various firing modes of the dopamine neurons and how addictive drugs alter them. Notably, I will present recent results on modelling effects of alcohol on dopaminergic dynamics and dopamine outflow. Here i will show how changes in the inhibitory input synchrony to the dopamine neurons may promote high frequency firing. Time permitting, I will show how inout structure to the dopamine neurons may control their excitabilty type and what that may imply for their ability to encode reward related signals.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/dpa4fu5mfc4kt2igt6us4png6k","2017-02-12 20:17:20",NULL
"3753","14","Tea and cookies","2017-02-15 14:30:00","2017-02-15 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/79t50bd2uao8ufj4f727krlgp4","2017-02-13 11:26:16",NULL
"3754","14","Tea and cookies","2017-02-22 14:30:00","2017-02-22 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/p4fkdbc6o366g8oi014e3ika3g","2017-02-13 11:27:00","2017-02-20 13:21:31"
"3755","14","Tea and cookies","2017-03-15 14:30:00","2017-03-15 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/7v1k5lkd1vj0d9vbp2pb2tpu6g","2017-02-13 11:28:08","2017-02-20 13:21:26"
"3756","14","Tea and cookies","2017-03-21 14:30:00","2017-03-21 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/dkhdn0av7s91b13r1u72b4395s","2017-02-13 11:29:04","2017-03-13 09:29:39"
"3757","14","Tea and cookies","2017-03-29 14:30:00","2017-03-29 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/37e9qadtdg43c4peav6ee0ej60","2017-02-13 11:29:37",NULL
"3758","14","Tea and cookies","2017-04-05 14:30:00","2017-04-05 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/5qdheb1rmk6mdkbln9kj0rq9dc","2017-02-13 11:30:44",NULL
"3760","1","Challenges in multivalued matrix functions","2017-04-25 16:00:00","2017-04-25 17:00:00","SAS 1102","Nicholas Higham","http://www.maths.manchester.ac.uk/~higham/","University of Manchester","Ilse Ipsen",,"Multivalued matrix functions arise in solving various kinds of matrix equations.  The matrix logarithm is the prototypical example.  Another example is the Lambert W function of a matrix, which is much less well known but has been attracting recent interest.  A theme of the talk is the importance of choosing appropriate principal values and making sure that the correct choices of signs and branches are used, both in theory and in computation. We will give examples where incorrect results have previously been obtained.

We focus on matrix inverse trigonometric and inverse hyperbolic functions, beginning by investigating existence and characterization. Turning to the principal values, various functional identities are derived, some of which are new even in the scalar case, including a round trip formula that relates acos(cos A) to A and similar formulas for the other inverse functions.  Key tools used in the derivations are the matrix unwinding function and the matrix sign function.

A new inverse scaling and squaring type algorithm employing a Schur decomposition and variable-degree Pad approximation is derived for computing acos, and it is shown how it can also be used to compute asin, acosh, and asinh. In numerical experiments the algorithm is found to behave in a forward stable fashion and to be superior to computing these functions via logarithmic formulas.","schecter","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/9l6ngmb81c75b8siiq2gjq48s8","2017-02-13 11:45:19","2017-02-22 10:07:21"
"3762","3","The partition algebra, symmetric functions and Kronecker coefficients","2017-03-20 15:00:00","2017-03-20 16:00:00","SAS 4201","Rosa Orellana","https://math.dartmouth.edu/~orellana/","Dartmouth College",,,"The Schur-Weyl duality between the symmetric group and the general linear group allows us to connect the representation theory  of  these  two  groups.   A  consequence  of  this  duality  is  the  Frobenius  formula  which  connects  the  irreducible characters of the general linear group and the symmetric group via symmetric functions.   

The symmetric group is also in Schur Weyl duality with the partition algebra.   This duality allows us to introduce a new Frobenius type formula that connects the characters of the symmetric group and those of the partition algebra.   In this talk we introduce a new basis of the ring of symmetric functions which specialize to the characters of the symmetric group when evaluated at roots of unity.   Furthermore, the structure coefficients for this new basis of symmetric functions are the stable (or reduced) Kronecker coefficients.    We will also discuss  how this new basis allows us to use symmetric functions to study the representation theory of the partition algebra and the Kronecker coefficients. 

This is joint work with Mike Zabrocki.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/jfgp52tbm7i0h40qt3fu9pdfmg","2017-02-17 13:33:51","2017-03-06 16:04:02"
"3763","34","Trees matter: Using phylogenetics to model the outcome of polyploidy events","2017-03-17 13:30:00","2017-03-17 14:30:00","Park Shops 215","Gavin Conant",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/434jdq94aj717j3kjpb11s3e30","2017-02-17 16:08:56","2017-03-14 13:13:07"
"3764","34","Phylogenetic approaches for quantifying interlocus gene conversion","2017-03-24 13:30:00","2017-03-24 14:30:00","Park Shops 215","Xiang Ji",,"NC State",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/n7s25mkj8gb3j9v8gs0mkb9bvc","2017-02-17 16:13:21","2017-03-14 13:46:42"
"3765","34","Generality and robustness of the SVDQuartets method for species tree estimation","2017-03-31 13:30:00","2017-03-31 14:30:00","Park Shops 215","Dave Swofford",,"Duke",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9q2tt0m0bl985gs51fah8oiqqs","2017-02-17 16:14:09","2017-03-27 08:36:05"
"3766","46","Repulsive energies","2017-03-13 16:00:00","2017-03-13 17:00:00","SAS 4201","Philipp Reiter","https://www.uni-due.de/mathematik/agpozzi/reiter/","Duisburg Essen University","Radmila Sazdanovic",,"During the last thirty years, several (families of) functionals have been defined which model self-avoidance: their values tend to infinity if an embedded object degenerates, e.g., if a sequence of closed simple curves converges to a curve with a self-intersection. Many of these functionals exhibit regularizing effects: they not only ensure embeddedness but in fact provide some sort of curvature measure. They are interesting objects per se: in many cases the first variation turns out to be an elliptic pseudo-differential operator which under certain conditions permits to derive smoothness of critical points. On the other hand, repulsive functionals can be used to model impermeability of elastic objects: we present an example in which they are are applied to the evolution of inextensible curves under the elastic flow.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/onpuami1bg2aku80aghkfkbvcc","2017-02-18 07:35:38","2017-03-03 10:16:51"
"3767","9","Understanding the Impact of At Risk Populations for Analyzing Zika Virus in Central &amp; South American Countries","2017-02-23 16:20:00","2017-02-23 17:20:00","Cox 306","Deborah Shutt",,"Colorado School of Mines","Mette Olufsen",,,"allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/8h9njkb5n3vfi3f5gf6mnfimc0","2017-02-20 08:36:00",NULL
"3768","2","Partial Differential Equations: A Journey from Micro to Macro","2017-02-27 16:00:00","2017-02-27 17:00:00","SAS 4201","Jose A. Carrillo de la Plata",,"Department of Mathematics, Imperial College London",,,"What links gas molecules, charged particles, bacteria and fish? Partial differential equations help us understanding their collective behaviour. Kinetic modelling allows for a multi-scale strategy in a number of important applications in science and technology. Mean field limits and kinetic descriptions have become one of the most powerful tools in applied mathematics to bridge microscopic and macroscopic descriptions of many body systems. They typically involve a huge number of individuals, showing some sort of collective behaviour, from which we want to extract macroscopic information. Some classical and modern instances of applications are: molecules in gases, electron transport in semiconductor materials, grains or beads in granular flows, endothelial cells in chemotactic movement, and many others. The individual behaviour of the particles is typically modelled via stochastic/deterministic ODEs leading to the most detailed description of the dynamics. From this microscopic picture, one obtains mesoscopic descriptions based on kinetic type PDEs, while the average dynamics is usually described via continuum mechanics systems of hyperbolic, diffusive, or hydrodynamic type. They are obtained as asymptotic limits of the kinetic descriptions.

<b>Biosketch:</b> Since 2012, Jose A. Carrillo has held a Chair in Applied and Numerical Analysis at Imperial College London. He was formerly <a href=""http://www.icrea.cat/"">ICREA Research Professor</a> at the <a href=""http://www.mat.uab.cat/"">Universitat Autonoma de Barcelona</a> during the period 2003-2012. He was visiting professor in several French universities including Paris-Dauphine, Paris-Sud, Toulouse, Marseille, Nice among others, CAS-Oslo (Norway), NUS (Singapore), Tsinghua-Beijing (China), Mittag-Leffler (Sweden) and has given more than 200 seminars in leading mathematics departments worldwide. He serves as chair of the <a href=""http://www.euro-math-soc.eu/committee/applied-math"">Applied Mathematics Committee</a> of the <a href=""http://www.euro-math-soc.eu/"">European Mathematical Society</a>.

His research program focuses on long-time asymptotics, qualitative properties and numerical schemes for nonlinear diffusion, hydrodynamic, and kinetic equations for modelling the collective behaviour of many-body systems such as rarefied gases, granular media, charge particle transport in semiconductors, or cell movement by chemotaxis. He was recognised with the <a href=""http://www.sema.org.es/web/index.php?option=com_content&task=view&id=10&Itemid=28"">SEMA prize</a> (2003) and the GAMM Richard Von-Mises prize (2006) for young researchers. He is a recipient of a <a href=""http://royalsociety.org/grants/schemes/wolfson-research-merit/"">Wolfson Research Merit Award</a> by the Royal Society.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/88dsd1gs5o93bouefoqtiaj2v4","2017-02-20 09:42:54","2017-02-27 09:33:50"
"3770","24","MGSA Recruitment Weekend Game Night","2017-02-24 20:00:00","2017-02-24 21:00:00","SAS 1216",,,,,,"MGSA is hosting a game night on Friday, February 24 at 8:00pm to welcome the visitors for recruitment weekend. All current graduate students are welcome. This is a great opportunity for the visitors to interact with the grad students. MGSA will provide snacks and drinks.","mrgaddy","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/r2ibuo306r275g5485j1h8itos","2017-02-20 10:10:28",NULL
"3771","6","Primal-Dual Weak Galerkin Finite Element Methods for PDEs","2017-03-21 15:00:00","2017-03-21 16:00:00","SAS 4201","Junping Wang","https://www.nsf.gov/staff/staff_bio.jsp?lan=jwang&org=NSF","National Science Foundation","Zhilin Li",,"This talk will introduce a primal-dual finite element method for variational problems where the trial and test spaces are different. The essential idea behind the primal-dual method is to formulate the original problem as a constrained minimization problem. The corresponding Euler-Lagrange formulation then involves the primal (original) equation and its dual with homogeneous data. The two equations are linked together by using properly-defined stabilizers commonly used in weak Galerkin finite element methods. The primal-dual method will be discussed for three type of model problems: (1) second order elliptic equation in nondivergence form, (2) steady-state linear convection equations, and (3) elliptic Cauchy problems.

 

Weak Galerkin (WG) is a finite element method for PDEs where the differential operators (e.g., gradient, divergence, curl, Laplacian etc.) in the weak forms are approximated by discrete generalized distributions. The WG discretization procedure often involves the solution of inexpensive problems defined locally on each element. The solution from the local problems can be regarded as a reconstruction of the corresponding differential operators. The fundamental difference between the weak Galerkin finite element method and other existing methods is the use of weak functions and weak derivatives (i.e., locally reconstructed differential operators) in the design of numerical schemes based on existing weak forms for the underlying PDEs. Weak Galerkin is a natural extension of the classical Galerkin finite element method with advantages in many aspects. The goal of this talk is to demonstrate some of these advantages in numerical PDEs.

 

The talk will start with the second order elliptic equation, for which WG shall be applied and explained in detail. In particular, the concept of weak gradient will be introduced and discussed for its role in the design of weak Galerkin finite element schemes. The speaker will then introduce a general notion of weak differential operators, such as weak Hessian, weak divergence, and weak curl etc. These weak differential operators shall serve as building blocks for WG finite element methods for other class of partial differential equations, such as the Stokes equation, the biharmonic equation, the Maxwell equations in electron magnetics theory, div-curl systems, and PDEs in non-divergence form. The speaker will then discuss the primal-dual technique for the three model problems. The talk should be accessible to graduate students with adequate training in computational mathematics.","asaibab","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/5eiocliv78pk6s0u1r732e796g","2017-02-24 17:14:31",NULL
"3773","19","Mathematical Structures in Musical Spaces","2017-03-01 15:00:00","2017-03-01 16:00:00","SAS 2102","Yvonne Chazal",,,,,"Its been known for centuries that there are many connections between mathematics and music.  D. Tymoczko described and utilized the representation of n-note chords by n-dimensional orbifolds, opening up many possibilities for musical analysis.  A. Crans et al. formulate dihedral group actions from musical concepts whose commutativity is present in examples that span centuries.  In this talk, we will focus on music analysis via topological structures arising in Tymoczkos model and the group actions described by Crans, as well as the interactions between the two models.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9jdkd5reft72sjn68jh72m63e8","2017-02-26 11:01:36",NULL
"3774","14","Tea and cookies","2017-03-02 15:30:00","2017-03-02 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/rnm40qjldf19htqocbkpt5dnko","2017-02-27 09:22:17","2017-02-27 10:05:27"
"3775","14","Tea and cookies","2017-02-27 15:30:00","2017-02-27 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6go978sjam4op72n3ff2mepllo","2017-02-27 09:59:59","2017-02-27 10:05:32"
"3776","4","Growth Model for Tree Stems and Vines","2017-04-19 15:00:00","2017-04-19 16:00:00","SAS 4201","Michele Palladino",,"Penn State University","Khai Nguyen",,"In this talk, we propose a model describing the growth of tree stems and vine, taking into account also the presence of external obstacles. The system evolution is described by an integral differential equation which becomes discontinuous when the stem hits the obstacle. The stem feels the obstacle reaction not just at the tip, but along the whole stem. This fact represents one of the main challenges to overcome, since it produces a cone of possible reactions which is not normal with respect to the obstacle. However, using the geometric structure of the problem and nonlinear analysis tools, we are able to prove existence and uniqueness of the solution under natural assumptions on the initial data.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/svkrfevi64982tpd2p5cjfbfsk","2017-02-27 11:34:48","2017-04-17 10:19:03"
"3777","28","Sonia Kovalevsky Day","2017-04-08 08:00:00","2017-04-08 11:45:00","SAS 2203",,,,,"https://www.math.ncsu.edu/forms/AWM/app/","The NC State Student Chapter of the Association for Women in Mathematics will host its 6th Annual Sonia Kovalevsky Day on Saturday morning, April 8. The event will feature mathematically-oriented games and workshops and a keynote talk by Cynthia Vinzant. It is free, and all 7th and 8th grade girls are welcome to attend. The registration deadline is Monday, April 3rd.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/hk55qaefihqlk51dcqqvtuscfo","2017-02-27 12:37:54","2017-03-13 11:43:45"
"3778","6","High order numerical methods for hyperbolic equations","2017-03-02 16:00:00","2017-03-02 17:00:00","SAS 1102","Chi-Wang Shu","http://www.dam.brown.edu/people/shu/","Brown University",,,"Hyperbolic equations are used extensively in applications including fluid dynamics, astrophysics, electromagnetism, semiconductor devices, and biological sciences.  High order accurate numerical methods are efficient for solving such partial differential equations, however they are difficult to design because solutions may contain discontinuities.  In this talk we will survey several types of high order numerical methods for such problems, including weighted essentially non-oscillatory (WENO) finite difference and finite volume methods, discontinuous Galerkin finite element methods, and spectral methods.  We will discuss essential ingredients, properties and relative advantages of each method, and provide comparisons among these methods.  Recent development and applications of these methods will also be discussed.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2r0hje6rbt8phtbldkasvaip7o","2017-02-28 11:24:12",NULL
"3779","21","Sonia Kovalevsky Day","2017-04-08 08:00:00","2017-04-08 12:00:00","SAS Hall",,,,,"https://www.math.ncsu.edu/forms/AWM/app/","Our goal is to encourage young women to continue their study in mathematics and to help build a relationship between the areas universityand industrial mathematicians and those in local schools!If you are interested in attending, please fill out https:www.math.ncsu.eduformsAWMapp","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/5g3p9un91rj9saklke9naq6b70","2017-03-03 12:28:34","2017-03-14 12:17:46"
"3780","3","The Berenstein-Kirillov group and cactus groups","2017-04-03 15:00:00","2017-04-03 16:00:00","SAS 4201","Max Glick","http://www.math.uconn.edu/~glick/","University of Connecticut",,,"Berenstein and Kirillov have studied the action of Bender-Knuth moves on semistandard tableaux.  Losev has studied a cactus group action in Kazhdan-Lusztig theory; in type A this action can also be identified in the work of Henriques and Kamnitzer.  We establish the relationship between the two actions.  We show that the Berenstein-Kirillov group is a quotient of the cactus group.  We use this to derive previously unknown relations in the Berenstein-Kirillov group.  This is joint work with M. Chmutov and P. Pylyavskyy.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/mfqlqcb75nligc6na0bbv17sco","2017-03-06 11:33:47","2017-03-24 13:40:52"
"3781","24","MGSA Pi Day Celebration","2017-03-14 14:00:00","2017-03-14 15:30:00","SAS 4104",,,,,,"In honor of Pi Day, MGSA will provide pie in the 4th floor lounge of SAS on Tuesday, March 14 between 2:00-3:30 pm. Please stop by for a slice of pie, and feel free to bring some pie to share.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/dqadg0s0fmdnmtq7qd2r3u9hc0","2017-03-12 20:08:31","2017-03-13 09:41:17"
"3782","15","Anderson Acceleration: Convergence Theory and Numerical Experience","2017-03-15 16:30:00","2017-03-15 17:30:00","SAS 2229","Tim Kelley","http://www4.ncsu.edu/~ctk/","NC State",,,"You\'ve probably heard some old guy rant about Newton\'s method and how it will solve all of your problems: linear, nonlinear, personal, laundry. There\'s more. In this talk I\'ll tell you about a way to accelerate plain vanilla fixed point iteration. The first theory for this stuff came from right here in SAS hall and there\'s much more to do. I\'ll tell you some of the theory, explain why you care in the first place, and show you some research opportunities.","jlhart3","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/np4mmoeen6qvre4voqt4ipipm8","2017-03-13 10:36:27","2017-03-13 12:46:57"
"3785","38","Simulating non-dilute transport in porous media using a TCAT-based model; advised by Ralph Smith","2017-04-13 13:00:00","2017-04-13 15:00:00","SAS 3282","Deena Hannoun Giffen",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/na0fqm8bn51jc1tdb09vpp4phg","2017-03-13 14:47:02","2017-03-14 09:50:04"
"3786","38","Development of well-balanced and asymptotic preserving numerical methods for partial differential equations - advised by Alina Chertock","2017-03-22 14:00:00","2017-03-22 16:00:00","SAS 3282","Seyma Nur Ozcan",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/hm5hdrdu60h91315j5rbnq8qrk","2017-03-13 14:55:59",NULL
"3787","46","Homotopy Group Actions and Group Cohomology","2017-04-12 16:00:00","2017-04-12 17:00:00","SAS 4201","Alejandro Adem","http://www.math.ubc.ca/~adem/","University of British Columbia","Radmila Sazdanovic",,"Let G denote a finite group and X a CW-complex. A homotopy group action is defined as a homotopy class of maps BG -- BAut(X). In this talk we will analyze these actions using techniques from group cohomology. We will show how they relate to geometric actions and how they can be used to construct new and somewhat exotic examples.This is joint work with Jesper Grodal.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/di6n4p401btoenlbvgs32g0t9k","2017-03-13 19:31:26",NULL
"3788","4","The Monge-Ampere eigenvalue problem and global smoothness of the eigenfunctions","2017-04-27 15:00:00","2017-04-27 16:00:00","SAS 4201","Nam Le","http://pages.iu.edu/~nqle/","Department of Mathematics, Indiana University","Khai Nguyen",,"In this talk, I will first introduce the Monge-Ampere eigenvalue problem on general bounded convex domains and related analysis. Then I will discuss the recent resolution, in joint work with Ovidiu Savin, of global smoothness of the eigenfunctions of the Monge-Ampere operator on smooth, bounded and uniformly convex domains in all dimensions. A key ingredient in our analysis is boundary Schauder estimates for certain degenerate Monge-Ampere equations.","tnguye13","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/lau44u57tcdj3q0e1rart1p5bk","2017-03-14 09:39:27","2017-04-10 09:31:33"
"3789","34","A statistically consistent coalescent-based k-mer method for phylogenetic tree reconstruction","2017-04-07 13:30:00","2017-04-07 14:30:00","Park Shops 215","Chris Durden",,"NCSU",,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/p3fq38mh8sfmba7kcn2dujtqqc","2017-03-14 13:48:45","2017-04-03 08:36:26"
"3791","19","Supersymmetric Bilinear Forms and Oscillator Algebras","2017-03-22 15:00:00","2017-03-22 16:00:00","SAS 2102","McKay Sullivan",,,,,"Many important Lie (super)algebras can be constructed using bosonic and fermionic oscillators. We introduce inhomogeneous supersymmetric bilinear forms on a complex superspace and show that they lead to oscillator-like superalgebras. We classify such forms for superspaces up to dimension 7 and mention a few examples of subalgebras obtained from the corresponding superalgebras. This talk is based on joint work with Bojko Bakalov.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/4p749ggndu7bcj6k2q5uje4au8","2017-03-15 12:44:00","2017-03-19 14:00:43"
"3792","19","Degree-optimal Moving Frames for Rational Curves","2017-03-29 15:00:00","2017-03-29 16:00:00","SAS 2102","Zach Hough",,,,,"I will present an algorithm that, for a given vector of n relatively prime polynomials in one variable over an arbitrary field, outputs an invertible matrix with polynomial entries such that it forms a degree-optimal moving frame for the rational curve defined by the input vector. From an algebraic point of view, the first column of the matrix consists of a minimal-degree Bezout vector (a minimal-degree solution to the univariate effective Nullstellensatz problem) of the input vector, and the last n-1 columns comprise an optimal-degree basis, called a mu-basis, of the syzygy module of the input vector. The algorithm and underlying theory are based on elementary linear algebra and will be accessible to all. This is a joint work with Drs. Hoon Hong and Irina Kogan.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9308aus2f2npchq4bt6mseqvkk","2017-03-15 12:44:49","2017-03-26 17:48:24"
"3793","19","Signature Map on Algebraic Varieties","2017-04-05 15:00:00","2017-04-05 16:00:00","SAS 2102","Michael Ruddy",,,,,"Let G be a Lie group acting smoothly on the plane. Then two smooth curves C and C\' are G-equivalent if there exists some g in G such that gCC\'. Can we answer the question, when are two curves G-equivalent? What can we additionally say if we restrict our attention to algebraic curves? In this talk we will first introduce the signature map and explain how it can help identify when two smooth curves are G-equivalent. Then we will investigate the signature map on algebraic curves and what additional information we can glean using Bezout\'s and Bertini\'s Theorem. The talk will be accessible and will review much of the background information. This is joint work with Drs. Irina Kogan and Cynthia Vinzant.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/tv55md9i6ruduu3pkc2h03jgic","2017-03-15 12:45:33","2017-04-03 08:29:42"
"3794","3","Quiver Hall-Littlewood symmetric functions and Kostka-Shoji polynomials","2017-04-21 16:00:00","2017-04-21 17:00:00","SAS 1102","Mark Shimozono","https://www.math.vt.edu/people/mshimo/","Virginia Tech",,,"We associate to any quiver a family of symmetric functions, defined by creation operators which are generalizations of Jing\s creation operators. For the cyclic quiver the coefficient polynomials were studied by Finkelberg and Ionov. Shoji has recently shown that the single variable specialization of the Finkelberg-Ionov polynomials agree with polynomials he studied in relation to Green functions for reflection groups. For the cyclic quiver we give an explicit conjecture for the Finkelberg-Ionov polynomials involving multitableaux and charge. We conjecture Schur positivity for any quiver. This is joint work with Dan Orr.","riliu","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2poim4b7kguu1nuudtcj5m562g","2017-03-15 14:30:31","2017-04-17 12:47:33"
"3795","14","NSF Funding Trends: Questions and answers session","2017-03-21 16:00:00","2017-03-21 16:30:00","SAS 4201","Dr. Junping Wang",,"NSF","Zhilin Li",,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/jrlqd1b95hp2ug5l8riuvqv2nc","2017-03-17 10:28:03",NULL
"3796","21","GAMMA: Girls in Applied Math, Modeling, and Analysis","2017-04-08 13:00:00","2017-04-08 17:00:00","SAS Hall",,,,"Bociu","http://www.math.ncsu.edu/News/2017GammaPoster.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/v1390ktlrd6mkp6fve04cqseq0","2017-03-17 12:19:50",NULL
"3797","38","Numerical study and feedback stabilization of a linear hydro-elasticity model - advised by Lorena Bociu","2017-03-27 14:00:00","2017-03-27 16:00:00","Mann 301","Steven Desrochers",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/lkpgf3ht00vuf2r5ae0j9ntnhg","2017-03-20 09:36:34",NULL
"3798","21","TAGMaC conference at Duke","2017-04-23 09:00:00","2017-04-23 16:00:00","Duke Physics Building, NC",,,,,"https://trianglemath.wordpress.com/about/","This semester, the Duke University AMS and SIAM graduate student chapters will host the biannual Triangle Area Graduate Mathematics Conference (TAGMaC). The event will occur on Sunday April 23 in the Duke Physics Building. The plenary speaker will be new UNC Professor Dave Rose. The organizers are Hangjie Ji, Sarah Ritchey, Shan Shan, and Dmitry Vagner.The goal of TAGMaC is for students in the graduate mathematics departments (NC State, UNC Chapel Hill, Duke) in the Triangle Area to come together as a mathematical community to share in their various mathematical experiences. Graduate students will give 20 minute talks about their research. The talks need not be presentations of precise mathematical results. Rather, the purpose is for the talks to introduce other graduate students to one\'s area of research: what sort of concepts and problems is one considering? where within mathematics do one\'s interests lie? what is the path of ideas, from graduate courses to the advanced papers in the field, that one has to traverse to arrive at their work? What are some fascinating phenomena you\'d like to share? We want you to tell us the mathematical story of your research so as to demystify unfamiliar areas of mathematics as well as, for younger graduate students, the world of mathematical research. This is the perfect opportunity to give your first research talk! No need to be shy when we\'re all among peers. The schedule will tentatively be as follows: 9-10: breakfast  welcome10-12: session I talks12-1: lunch1-2: plenary talk2-4: session II talks","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/jajh7h5igsaegpria612452i1o","2017-03-20 14:23:05",NULL
"3799","8","The Complexity of Adaptive Subdivision in High Dimensions","2017-04-25 15:00:00","2017-04-25 16:00:00","SAS 2102","Michael Burr","https://cecas.clemson.edu/~burr2/","Clemson",,,"In 2006, Plantinga and Vegter introduced an algorithm for approximating a real planar curve.  Their algorithm is based on subdivision and interval arithmetic, and the output is certified to be topologically correct.  Through experiments, Plantinga and Vegter claimed their algorithm was efficient in practice.  In this talk, I will explore this efficiency claim, provide the first complexity analysis of this algorithm, and show that this bound is tight.  This is joint work with Shuhong Gao and Elias Tsigaridas.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/t45uf015n7hmg9s2de625o2958","2017-03-20 18:28:05","2017-04-25 08:22:52"
"3800","23","GIST panel: Education research in undergraduate mathematics","2017-04-05 16:00:00","2017-04-05 17:00:00","SAS 2102",,,,,,"We\'ll be focusing on education research in undergraduate mathematics (using it to improve our teaching and learning more about how its done). Our panelists are Karen Keene (Associate Professor and Graduate Program Coordinator in NCSU Stem Ed department) and Jack Bookman (Professor of the Practice Emeritus in the Duke Mathematics department).","gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/ssde9vl9mp3i69n8nl2f0tebac","2017-03-21 18:33:31","2017-03-21 18:35:07"
"3801","38","Error analysis of the immersed interface method for elliptic problems with an interface","2017-04-28 14:30:00","2017-04-28 16:30:00","SAS 3282","Rui Hu",,"NC State Mathematics Graduate Student",,,"advised by Zhilin Li","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/kqv3raho22qam9r64bqh5osso0","2017-03-22 11:50:05","2017-04-17 14:09:46"
"3802","14","Faculty Meeting","2017-03-22 16:00:00","2017-03-22 17:00:00","SAS 1102",,,,,,"The agenda items include:The Endowed Professorship Search Committee will present the outcome of the search.Last minute updates and Q&amp;A session in preparation for the upcoming external review.I have included the original email for your reference:Dear All,1) As promised, attached is the current version of the agenda for the upcoming Departmental review. It has been put together by the Graduate school and includes, among other things, two faculty meetings with the review team:The first meeting (for the mathematics faculty) is scheduled for Monday, March 27, 1:00PM-2:00PM, in SAS 4201. The Heads of the Graduate Programs and Department Head (Pierre, Alun and Alina &amp; Alina) do not attend the meeting. Since OR and Financial Math are not involved in this review (they are reviewed separately as cross-departmental programs) the DGPs of those programs are welcome in this faculty meeting. The discussion items are specified in the agenda.The second meeting (for both the mathematics and biomathematics faculty) is scheduled for Tuesday, March 28, 2:00PM-3:00PM, in SAS 4201, and includes the Heads of the Graduate Programs and Department Head. The review team is expected to present tentative findings and recommendations during this meeting. 2) I would also like to call a faculty meting next Wednesday, March 22, 4:00-5:00, in SAS 1102. The agenda items include:The Endowed Professorship Search Committee will present the outcome of the search.Last minute updates and Q&amp;A session in preparation for the upcoming external review.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/l05tu5j1b9336eb9jjv28vfjns","2017-03-22 13:12:46",NULL
"3803","22","Physics in Flatland: The 2016 Nobel Prize","2017-03-30 16:30:00","2017-03-30 17:20:00","SAS 2102","Dan Scofield",,"NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/033017.pdf",,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/spto0pc9c2md9vn5qltd814oko","2017-03-23 08:09:25","2017-03-28 10:49:16"
"3804","22","Why don't we (usually) faint when we stand up?","2017-04-06 16:30:00","2017-04-06 17:20:00","SAS 2102","Mette Olufsen","http://www4.ncsu.edu/~msolufse/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/040617.pdf","Basic physics suggests that when we stand up, the blood pressure in our brain should drop dramatically. Such a pressure drop should cause us to faint. But most of us don’t faint when we stand up. In this talk I’ll discuss a mathematical model that explains why most of us don’t, and why some people do. The model is a compartmental model formulated as a system of ordinary differential equations. Another important question is: How do we make this model predict what is observed in a specific patient? Mathematically this relates to the question: How do we estimate a set of parameters that allow the model to predict responses observed in data?","spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/migu6gd1ndt3bip1qlk32k52l0","2017-03-23 08:11:17","2017-03-29 10:51:33"
"3805","8","Pythagoras numbers of real projective varieties","2017-04-18 15:30:00","2017-04-18 16:30:00","SAS 2102","Rainer Sinn","http://people.math.gatech.edu/~rsinn3/","Georgia Tech",,,"The Pythagoras number of field F, studied in the theory of quadratic forms, is the smallest k such that every sum of squares in F is a sum of k squares. We will reinterpret this definition for coordinate rings of real projective varieties and discuss ways to give bounds on this invariant. A central concept for lower bounds is what we call quadratic persistence of a projective variety.","clvinzan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/p43r08qei5s22lvdpjr9jvnnf0","2017-03-23 12:59:20","2017-04-11 15:17:38"
"3806","14","Faculty Meeting with the Review Team","2017-03-27 13:00:00","2017-03-27 14:00:00","SAS 4201",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/u1penpomq13r1rh1uv1p3miea4","2017-03-28 10:47:36",NULL
"3807","14","Exit Meeting between the Faculty and the Review Team","2017-03-28 14:00:00","2017-03-28 15:00:00","SAS 4201",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/erlve7fadabpj4m6rigq0p1o0k","2017-03-28 10:48:13",NULL
"3808","24","MGSA Officer Elections and Ice Cream Social","2017-04-07 13:30:00","2017-04-07 14:30:00","SAS 4104",,,,,,"MGSA is providing ice cream on Friday, April 7 in the fourth floor lounge of SAS from 1:30-2:30pm. We will be holding our new officer elections at 2:00pm. All math grad students are welcome.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/jfu6o4bp73hhuk72b3mo2et748","2017-03-31 16:10:09","2017-04-03 13:43:05"
"3810","9","Hill: Aspects of the cardiovascular system:(i) coupling between the left ventricle and systemic arteries, and (ii) arterial dissection; Luo: Soft tissue mechanics and fluid-structure interaction in the cardiac system","2017-04-06 16:20:00","2017-04-06 17:20:00","Cox 306","Nick Hill and Xiaoyu Luo",,"School of Mathematics and Statistics, University of Glasgow","Mette Olufsen",,"Thursday April 6th, 4:20pm, Cox 306Nick HillSchool of Mathematics and Statistics, University of Glasgow(Nicholas.Hill@glasgow.ac.uk,  http:www.maths.gla.ac.uknah)Title: Aspects of the cardiovascular system:(i) coupling between the left ventricle and systemic arteries, and (ii) arterial dissection.    Abstract:Two topics in mathematical and computational modelling of the systemic arterial circulation will be discussed. First, an immersed boundary model of the left ventricle (LV) is coupled to a structured tree model of the systemic arteries. There is good agreement with clinical observations, and the relationship between active stress in the LV wall, LV pressure and flow rate are studied in cases of pathological cardiovascular function. Secondly, studies of the dissection (tearing) of the wall of the aorta using the HGO constitutive law reveal the role played by collage fibre orientation. Complex buckling patterns of inner wall are shown to be qualitatively similar to those seen in MRI scans.---------Xiaoyu LuoSchool of Mathematics and Statistics, University of Glasgow(xiaoyu.luo@glasgow.ac.uk,  http:www.maths.gla.ac.ukxl)Title: Soft tissue mechanics and fluid-structure interaction in the cardiac systemAbstract:This talk will start with an overview of the invariant-based continuum mechanics approach for anisotropic soft tissues that undergo nonlinear large deformation. I will then report how we model the cardiac system using the invariant-based constitutive laws and a fluid-structure interaction solver.   The models will be patient-specific derived from in vivo clinical magnetic resonance images (MRI), with material parameters determined using inverse and statistical approaches so that the model results agree with in vivo observations.  We model the cardiac function both in diastole and in systole, and consider agent-based modelling for myocardial infarction, soft tissue changes informed by MRI perfusion measurements, heart-valve, and heart-circulation interactions.   Finally, I will briefly introduce the EPSRC funded SofTMech Centre and the ongoing research themes in the Centre.","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/sjh1609dhcd489enjigmai6ios","2017-04-02 21:19:01","2017-04-02 21:23:54"
"3813","9","Chaos in ecology: A theoretical approach and a direct application using examples from fisheries","2017-04-04 16:20:00","2017-04-04 17:20:00","Cox 306","Laura Storch","https://sites.google.com/site/storchlauras/home","Department of Mathematics and Statistics, University of New Hampshire","Mette Olufsen",,"Laura Storch, Department of Mathematics and Statistics, University of New HampshireTuesday April 4th, 4:20pm, Cox 306Chaos in ecology: A theoretical approach and a direct application using examples from fisheries.  Part 1: A theoretical approachChaotic dynamics have been directly detected in ocean dwelling species, and asymmetrical advective dispersal is the dominant dispersal mechanism in the ocean. Therefore, we must better our understanding of chaotic population dynamics under the influence of a unidirectional current.  Here, we examine a spatially explicit, density-dependent population in a unidirectional current, where offspring are dispersed some distance downstream of the parent generation.  This system displays a rich variety of dynamics from chaotic to steady-state depending on the distance the offspring are moved downstream, the diffusive spread of the offspring (which can be interpreted as a stochastic component of the advection), and the domain size.  We will illustrate how advection can serve as a stabilizing or destabilizing force, depending on its size relative to the domain sizediffusive spread.  Improving our understanding of the dynamics of these systems will aide in conservation and sustainable management efforts.        Part 2: Nonlinear dynamics in fisheries data versus nonlinear dynamics in fisheries modelsHere, we present an example of directly detected nonlinear dynamics in time series of fish abundance, and illustrate how nonlinearity can be used as a characteristic to assess whether parametric models of complex marine ecosystems are capturing the underlying dynamics of the systems theyre modeling.  All models are simplified approximations of reality, but a models utility is contingent on its suitability for a given task.  This is particularly true of fisheries models, which are used to inform management of commercially important species.  Using nonlinear nonparametric forecasting methods, we will show that raw fisheries data sets have a higher prevalence of nonlinearity and lower predictability than fisheries model outputs, suggesting that model outputs may underestimate variability and overestimate stability.  Thus, caution is warranted: using such models for management or scenario exploration may produce unforeseen consequences, especially in the context of unknown future impacts.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/grugsbmjnv4dip7uehab1nat6s","2017-04-02 21:25:02","2017-04-03 09:21:23"
"3814","10","Expected Utility Maximization for Jump-diffusion Process with Bankrupt Prohibition and its Application to Finance","2017-04-03 15:00:00","2017-04-03 16:00:00","Daniels Hall 434","Zhibin Liang",,"School of Mathematical Sciences  Nanjing Normal University Jiangsu, P R China",,,"In this paper, we consider an optimization problem for jump-diffusion process under the expected utility maximization criterion with bankruptcy prohibition, i.e., the wealth process is not allowed to be below zero at any time.  By the standard martingale approach, we prove that under some conditions the non-negativity of terminal wealth can guarantee the non-negativity of the wealth process at any time, and the terminal wealth can be replicated by some portfolio.  Based on these results, we decompose the original problem into two sub-problems, by solving these two sub-problems, we derive the closed-form solutions for the optimal results.  Furthermore, we investigate the relationship of the optimal results between two cases with and without non-bankruptcy prohibition, and find that the optimal results will be the same under some non-trivial conditions.  This interesting phenomenon is shown in some examples:  for the portfolio optimization problem of the self-financing model, or for the optimal reinsurance problem with cheap reinsurance, the optimal results are the same for these two cases with and without bankruptcy prohibition.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/9rqk2udf1q2is8h1u5fbu6knv4","2017-04-03 09:23:09",NULL
"3815","46","A Smooth TQFT Approach to sln Homology","2017-04-19 16:00:00","2017-04-19 17:00:00","SAS 4201","Dmitry Vagner",,"Duke University","Radmila Sazdanovic",,"Given a link diagram L, one can apply a Skein relation to each crossing to yield a cube of resolutions. These skein relations come from the braiding in the category of Uq(sln) representations. When n2, we have the Khovanov cube of resolutions with edge maps defined by (co)pants conordisms. We may then apply a smooth TQFT, flatten the complex, and take homology to extract Khovanov homology. The case is more complicated when n2 because, due to the higher complexity of morphisms among fundamental representations, the resolution diagrams will contain trivalent vertices. The first definition, due to Khovanov and Rozansky, defined the invariants in the category of matrix factorizations. A more diagrammatic and combinatorial approach, taken by Queffelef-Rose, considers foam cobordisms---those with seams---between trivalent graphs and exploits skew-Howe duality to define a foam-like TQFT on them so as to extract homology. In this work, joint with Michael Abel, we apply a virtual filtration---another Skein-like relation, justified by the behavior of matrix factorizations---to resolve all trivalent graphs to their own cubes of smooth resolutions. With a little work, this yields a triple complex from which we extract a spectral sequence whose second page is equivalent to the Khovanov-Rozansky sln homology of the link.","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/i76da4c6gcpf1juk29vp4fg8i8","2017-04-03 10:06:30",NULL
"3816","14","Tea and Cookies","2017-04-10 15:30:00","2017-04-10 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/070k8u9vnrv4i28fgdjbq0j8d0","2017-04-03 11:00:11","2017-04-10 09:57:24"
"3817","28","Elections and Ice Cream Social","2017-04-21 14:00:00","2017-04-21 15:00:00","SAS 3281",,,,,,"Come relax with some free ice cream and AWM at our end of the year ice cream social! We will also be electing officers for next year at this event.","ayadava","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/08mv94dct7j6q9ta5aph2es8q0","2017-04-03 16:51:38",NULL
"3818","10","Levy-type Nonlinear Stochastic Dynamic Systems","2017-04-17 15:00:00","2017-04-17 16:00:00","Daniels Hall 434","G. S. Ladde",,"Department of Mathematics and Statistics University of South Florida",,,"In this talk, we consider a prototype stochastic model for dynamic processes in biological, chemical, economic, financial, medical, military, physical, technological and social sciences.  The dynamic model is described by Levy-type nonlinear stochastic differential equation. The model validation is established by the usage of Lyapunov-like function. The basic innovative idea is to transform a Levy-type nonlinear stochastic differential into a simpler stochastic differential equation that is easily tested for the existence and uniqueness of theorem.  Using the nature of Lyapunov-like function, the existence and uniqueness of solution of the original Levy-type nonlinear stochastic differential equation is established.  The main idea of the proof is based on the property of the one-to-one and onto transformation.  As the byproduct of the analysis, it is shown that the closed form implicit solution of transformed stochastic differential equation is a positive martingale.  Furthermore, using the change of measure, a Girsanov-type theorem for Levy-type nonlinear stochastic dynamic model is established.  This work is joint with postdoctoral fellow Youngsoo Seol.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qd8r6k7h4n9hqqfpv39570ul6g","2017-04-11 11:00:53",NULL
"3819","1","Eigenvalues, invariant and random integer matrices","2017-04-20 16:00:00","2017-04-20 17:00:00","SAS 1102","Mark Giesbrecht",,"University of Waterloo",,,"Integer matrices are often characterized by the lattice of combinations of their rows or columns. This is captured nicely by the Smith canonical form, a diagonal matrix of invariant factors, to which any integer matrix can be transformed through left and right multiplication by unimodular matrices.  Algorithms for computing Smith forms have seen dramatic improvements over the past 40 years, but effective algorithms for large sparse matrices have proven somewhat elusive.

Integer matrices can also be viewed as complex matrices, with eigenvalues and eigenvectors, and every such matrix is similar to a unique one in Jordan canonical form.  There is a wealth of effective numerical and symbolic methods for computing eigenvalues.  Krylov-type algorithms are also very useful for computing with sparse matrices, even in the symbolic domain or over finite fields.

It would seem a priori that the invariant factors and the eigenvalues would have little to do with each other.  Yet we will show that for &quot;almost all&quot; matrices the invariant factors and the eigenvalues are equal under a p-adic valuation, in a very precise sense.

A much-hoped-for link is explored for fast computation of Smith forms of sparse integer matrices, via the better understood algorithms for computing eigenvalues and effective preconditioning.  All the methods are elementary and no particular background beyond linear algebra will be assumed.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/3q5a4bflgfknc63lk4q3qaqd8o","2017-04-11 11:17:50","2017-04-11 11:28:49"
"3822","14","Tea and Cookies","2017-04-20 15:30:00","2017-04-20 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/7ebp3mhkhueu90mkm1ovisa6uk","2017-04-17 10:18:18",NULL
"3823","14","Tea and Cookies","2017-04-25 15:30:00","2017-04-25 16:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/qtp6kjec1skcq3ilm8in3g5foo","2017-04-17 12:42:32",NULL
"3824","22","Self-Folding of Thermoplastic Polymer Sheets from 2D to 3D","2017-04-20 16:30:00","2017-04-20 17:20:00","SAS 2102","Duncan Davis","https://www.cbe.ncsu.edu/people/duncan-davis/","NC State",,"https://web.math.ncsu.edu/sumseries/spring2017/042017.pdf",,"spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qnvq6ht47o80aqg6uaqladdu28","2017-04-18 11:00:02",NULL
"3825","46","Factorization Homology and Graph Homology","2017-05-03 15:00:00","2017-05-03 16:00:00","SAS 4201","Vladimir Baranovsky","https://www.math.uci.edu/~vbaranov/","UC Irvine","Radmila Sazdanovic",,"We give a brief overview of factorization homology theory due to Ayala, Francis and Tanaka and explain how it leads to a (still mostly conjectural) generalization of graph homology to homotopy commutative algebras, and an efficient computation of knot invariants coming from factorization homology (at least for alternating links).","rsazdan","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/j1m865g6ie90me7b4gqj5hlqjg","2017-04-18 13:59:58","2017-04-18 15:48:00"
"3826","26","AMS NCSU Graduate Student Chapter Elections","2017-04-20 12:00:00","2017-04-20 13:00:00","SAS 4104",,,,,,"The AMS NCSU Graduate Student Chapter would like to invite you to a free pizza social in the 4th floor lounge from 12:00pm to 1:00pm tomorrow, April 20th. We will be having officer elections for the coming semester so you may listen to them speak and cast your vote.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/62061smh608qhn3mhgbusnf3v0","2017-04-19 10:19:49",NULL
"3827","3","Demazure flags, Chebyshev polynomials and mock theta functions","2017-06-05 14:00:00","2017-06-05 15:00:00","SAS 4201","Rekha Biswal",,"Universite Laval, Canada",,,"The g[t]-stable Demazure modules are a lot of interest because of their connections to representation theory of quantum affine algebras. These modules are indexed by a pair (\ell, \lambda) where \ell is a positive integer and \lambda is a dominant integral weight of g and are denoted as D(\ell,\lambda). Naoi proves that for m&gt;=\ell, D(\ell,\lambda) admits a level m Demazure flag for an arbitrary simple Lie algebra g. In this talk, we will discuss the level m Demazure flag of D(\ell,\lambda) for the current algebra associated to sl_2. We will give a direct and constructive proof of Naois theorem in the case of sl_2. We will also see how the generating series of numerical multiplicities of Demazure modules in the Demazure flag of local Weyl modules relates to Chebyshev polynomials and how the generating series of graded multiplicities of Demazure modules in local Weyl modules relate to Ramanujans fifth order mock theta functions (surprisingly) in certain special cases. This is based on joint work with Vyjayanthi Chari, Lisa Schneider and Sankaran Viswanath.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/2dhsfp67o3bmefm4q7ai51nv08","2017-04-19 10:40:41","2017-05-05 09:33:05"
"3828","22","Honors Research Presentations","2017-04-26 16:30:00","2017-04-26 17:30:00","SAS 2102","Ephraim Bililign, Taylor Garnowski, William Reese and Brandon Summers",,"NC State Undergraduate Students",,,"1. Ephraim Bililign
 
Title: Measuring the temperature of granular systems

Abstract: Granular systems, or collections of athermal mesoscale particles, are immune to temperature in the conventional sense. Thus, to describe the behavior of an jammed assortment of grains, we turn to a modified thermodynamics built on forces and volumes. I will discuss the experimental measurements we made on a packing of photoelastic discs, which enabled us to identify forces and contacts throughout a granular system. Then, using the tools of statistical mechanics, I will present our analysis of one candidate for an analog to temperature: angoricity. (Faculty mentor: Dr. K. Daniels)
 

2. Taylor Garnowski

Title: Black Hole or Explosion? Using the Numerical Algorithm PUSH to Determine the Outcome of Collapsing Stars.

Abstract: When the cores of certain massive stars begin to contract at the end of their lives, their immediate future is uncertain. There are only two options for a star in this state: collapse all the way into a black hole or violently explode in whats called a core-collapse supernovae (CCSNe). Currently, theres no obvious indicator that tells us which option a star will take before it collapses. As a result, physicists and applied mathematicians have turned to the power of numerical modeling to help resolve this issue. In this talk, Ill present on a numerical algorithm, PUSH, that allows us to tie the fate of a collapsing star to one parameter. Ill provide a brief overview of the theory of CCSNe and the differential equations one needs to solve to model a collapsing star. Finally, Ill give some results when the PUSH algorithm is applied to a few different star types. (Faculty Mentor: Dr. C. Frohlich) 


3.  William Reese

Title: Statistical Properties of Solutions to Elliptic Partial Differential Equations with Random Coefficient Functions

Abstract: Elliptic partial differential equations (PDEs) are used for modeling various physical processes. Examples include vibrations of plates, fluid flow, and heat diffusion on a plate. In practice, the parameters in the PDE such as coefficient functions or boundary data are not known exactly. Hence, to model ones lack of precise knowledge about such parameters, it is natural to consider probabilistic approaches. This enables for example, characterization of statistical properties of system response, given a statistical model for the model parameters. We consider elliptic PDEs with random coefficient functions. This can for example model heat diffusion through a heterogeneous medium with a conductivity function modeled as a random field. The purpose of this research is to study the solution behavior of elliptic PDEs with random coefficients. The equations are solved numerically, using the finite element method. The random coefficient field is represented through its Karhunen Loeve (KL) expansion. Our main objective is to study the solution of the PDE. We find that even for coefficient functions with small correlation lengths, the statistics of the solution of the PDE can be represented accurately with a few KL modes. (Faculty mentor: Dr. A. Alexanderian )


4.  Brandon Summers
 
Title: Certifying Isolated Singularities of Plain Curves

Abstract: Consider a function f : R^{2} -&gt; R where f is from Z[X,Y]. We will focus on certifying the existence of the isolated singularities of the curve f^{-1}(0).  A point (x,y) is a singularity of f^{-1}, if the function f and all the partial derivatives of f vanish at (x,y).  This paper analyzes two different algorithms. The first is presented in the paper, Complete Subdivision Algorithms, II: Isotopic Meshing of Singular Algebraic Curves by Burr et al.  The second is presented in the paper Certifying Solutions to Overdetermined and Singular Polynomial Systems over Q by A. Szanto et al.  This paper provides an overview of both algorithms and a comparative analysis which considers the accuracy of the algorithms for different types of functions.  (Faculty mentor: Dr. A. Szanto)","spolste","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/fpcanfedeq4hr7l3n5pkkuj2rk","2017-04-20 13:55:32","2017-04-26 10:07:57"
"3829","38","Phase-field models of two-fluid flow in a capillary tube and Hele-Shaw cell - advised by Michael Shearer","2017-05-11 10:00:00","2017-05-11 12:00:00","SAS 4201","Melissa Strait",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/9mem9gej3r7j4su2g1k87v2jsc","2017-04-21 10:06:37","2017-04-24 14:25:07"
"3830","49","College wide faculty meeting","2017-04-28 15:00:00","2017-04-28 16:00:00","Dabney Hall 222",,,,,,"We are initiating a regular college wide faculty meeting each semester. At this first faculty meeting we will develop what we all hope to get out of regular college wide faculty meetings as well as having a chance to interact as a faculty.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/3f8h0ksrg9rt9ns8stf79k2o44","2017-04-21 13:18:26",NULL
"3831","14","Dr. Michael Singer, Dr. Thomas Lada and Dr. Stephen Schecter Retirement Reception","2017-04-21 14:00:00","2017-04-21 15:00:00","SAS 4104",,,,,,,"bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/f64cin7cevculo8ru1ie5hb9r4","2017-04-21 13:20:10",NULL
"3832","12","The rise of Multiprecision Computations","2017-04-26 13:00:00","2017-04-26 14:00:00","SAMSI","Nicholas J. Higham",,,,"https://www.samsi.info/higham-lec","https://www.samsi.info/for-visitors/directions-and-maps/","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/6hvcv1i7qhip2dhjjcg0981i54","2017-04-25 09:57:08",NULL
"3833","38","Relaxations to sparse optimization problems and applications - advised by Agnes Szanto and Hamid Krim","2017-05-10 09:00:00","2017-05-10 11:00:00","SAS 4201","Erik Skau",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/n4rknjgm6968ibgte416qlpkb8","2017-04-26 18:08:40",NULL
"3834","24","MGSA and AMS Cinco de Mayo Celebration","2017-05-05 11:30:00","2017-05-05 13:00:00","SAS 4104",,,"MGSA",,,"MGSA and AMS will be providing free Moes burritos to celebrate Cinco de Mayo and the end of the semester! All math grad students are welcome, but you must RSVP by Wednesday, May 3 at noon if you plan to eat a burrito. For info about how to RSVP, please email mgsa.ncstate@gmail.com. All math grad students are welcome.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/frrgn3ml2i3g41lflbfrbpvs3s","2017-04-28 15:37:59","2017-05-01 14:33:49"
"3835","3","On the universal central extension of certain Krichever-Novikov algebras","2017-05-15 14:00:00","2017-05-15 15:00:00","SAS 4201","Ben Cox",,"College of Charleston",,,"We will describe results on the center of the universal central extension of certain Krichever-Novikov algebras. In particular we will describe how various families of classical and non-classical orthogonal polynomials appear. We will also provide certain new identities of elliptic integrals. This material we will cover was obtained in joint work with V. Futorny, J. Tirao, M. S. Im, X. Gu, R. Luo, and K. Zhao.","bnbakalo","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/rci63qk1jfdit7l2klembqev5o","2017-05-01 10:47:18","2017-05-05 09:32:40"
"3836","48","Hidden Figures","2017-05-02 18:00:00","2017-05-02 21:00:00","SAS 1102","AMS Movie Night","https://web.math.ncsu.edu/ams/index.html",,"Radmila Sazdanovic",,"AMS will be hosting a special showing of Hidden Figures and  provide pizza and other snacks.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/b83oj7e960136u6p9l1ag7cins","2017-05-01 13:53:18","2017-05-01 14:30:27"
"3837","21","Reception and Town Hall Meeting - Chancellor\'s Visit","2017-05-02 14:30:00","2017-05-02 16:00:00","Riddick Hearth",,,,,,"Chancellor Woodson will conduct his annual visit to the College of Sciences on Tuesday, May 2, 2017.  A reception for all College of Sciences faculty and staff will take place at 2:30 p.m. on the Riddick Hearth followed by a Town Hall Meeting.

Everyone is encouraged to attend.","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/6m6n4s96q3i5rvqgnggqhk1q5k","2017-05-02 12:27:06",NULL
"3838","49","Faculty Meeting","2017-05-09 16:00:00","2017-05-09 17:00:00","SAS 4201",,,,,,"The agenda is 
1) Service Teaching
2) Revised committee structure","bennett","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/0d44s4fnv6rkhnro1sae8o50po","2017-05-08 11:24:51",NULL
"3839","38","Optimal control of moving interface and phase field separation models - advised by Kazufumi Ito","2017-06-30 11:00:00","2017-06-30 13:00:00","SAS 4201","Khalid Ali Alanezy",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ohfu264qmuj2vpvu5j8chvdujs","2017-05-18 13:43:50",NULL
"3840","38","Mathematical modeling of the acute inflammatory response &amp; cardiovascular dynamics in young men - advised by Mette Olufsen","2017-07-12 08:00:00","2017-07-12 10:00:00","SAS 4201","Renee Brady",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/ovghm7aio7dahq0lk7c5q5g194","2017-05-30 14:14:29",NULL
"3841","38","Twisted logarithmic modules of free field and lattice vertex algebras - advised by Bojko Bakalov","2017-06-27 14:00:00","2017-06-27 16:00:00","SAS 4201","Steven McKay Sullivan",,"NC State Mathematics Graduate Student",,,,"gremaud","1","http://www.google.com/calendar/feeds/ncsu.edu_icl34tuogrmo4c1k831cav4q3c@group.calendar.google.com/private/full/rgkf2b2das7sn4uphrb2km4e6o","2017-06-01 14:24:30",NULL
"3842","24","Qual Study Break!","2017-06-07 13:00:00","2017-06-07 15:00:00","SAS 4th floor lounge",,,"MGSA","MGSA",,"Please join MGSA for our first Qual Study Break of the summer! We will be hosting a pizza and ice cream party and invite all math graduate students to join!","memcmaho","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/5qehmknm776luj171s8de54aoc","2017-06-02 15:23:24",NULL
"3843","9","Statistical challenges when analysing emerging epidemic outbreaks","2017-06-15 10:30:00","2017-06-15 11:30:00","Cox 306","Tom Britton","http://staff.math.su.se/tom.britton/","Department of Mathematics, Stockholm University","Alun Lloyd",,"New infectious disease outbreaks have great impact on communities over the world, as recently manifested by the Ebola outbreak. An important statistical task is then to predict the future scenario with and with out preventive measures. In the current talk we will investigate such analyses and see how it can be improved. The main catch is that in the exponentially growing phase early on in an outbreak, several biases can occur if not taken account for: events with short delays will be over-represented. We will give some examples from the Ebola outbreak and see how the biases can be removed or at least reduced. (Joint work with Gianpaolo Scalia Tomba).","allloyd","1","http://www.google.com/calendar/feeds/ncsu.edu_623csisp8nu77ihlisj1t7mou4@group.calendar.google.com/private/full/qcanfmn7p7li9p2tfsbvi564p0","2017-06-12 08:13:13",NULL
"3844","24","Qual Study Break!","2017-07-06 11:00:00","2017-07-06 12:00:00","SAS 4th floor lounge",,,,"MGSA",,"Take a break from your qual studying and join MGSA for donuts and coffee from RIse! All math graduate students are welcome to join.","memcmaho","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/pqv4b5olf04a12q6e909ca9olg","2017-06-30 09:42:54",NULL
"3845","1",,"2017-11-10 16:00:00","2017-11-10 17:00:00","SAS 1102","Victor Kac","http://www-math.mit.edu/~kac/","MIT","Bojko Bakalov",,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_r0dck25g47h1lbptgfgmr803dk@group.calendar.google.com/private/full/e62uu5l771s8htrm5eb3pficms","2017-07-25 15:59:55",NULL
"3846","14","Tea and Cookies","2017-11-10 15:30:00","2017-11-10 16:00:00","SAS 4104",,,,,,,"smsulli2","1","http://www.google.com/calendar/feeds/ncsu.edu_ib9ar3td19i16tmb9av6lid748@group.calendar.google.com/private/full/4g058auo1ugu6m29sqr6e5poso","2017-07-25 16:06:34",NULL