## Seminars

## Applied Math Colloquium - Andreas Kloeckner

Oct. 4, 2019

Andreas Kloeckner Department of Computer Science, University of Illinois Fast Algorithms for the Evaluation of Layer and Volume Potentials I will present new, asymptotically fast algorithms with high-order error bounds for the evaluation of layer and volume potentials in two and three dimensions. The efficient evaluation of both types of...

## Complex/Dynamical Systems Seminar - Bernd Kraukopf and Hinka Osinga

Oct. 3, 2019

Bernd Krauskopf and Hinka Osinga Department of Mathematics, University of Auckland Hetero-dimensional Cycles and Blenders Recent theoretical work on partially hyperbolic systems by Bonatti and Diaz (and others) has shown that chaotic dynamics may occur C1-robustly in diffeomorphisms of dimension at least three. More specifically, the existence of hetero-dimensional cycles...

## Math Bio Seminar - Erin Ellefsen

Oct. 1, 2019

Erin Ellefsen Department of Applied Mathematics University of Colorado Boulder Efficiently finding steady states of nonlocal territorial models in Ecology There are certain populations of animals that tend to move in social groups. We investigate territory development of these social groups by studying a system of non-local continuum equations. However,...

## Stats, Optimization, and Machine Learning Seminar - Yury Makarychev

Oct. 1, 2019

Yury Makarychev Toyota Technological Institute at Chicago (TTIC) Performance of Johnson-Lindenstrauss Transform for k-Means and k-Medians Clustering Consider an instance of Euclidean k-means or k-medians clustering. We show that the cost of the optimal solution is preserved up to a factor of (1+ε) under a projection onto a random O(log(k/ε)/ε^2)-dimensional...

## Applied Math Colloquium - Rebecca Morrison

Sept. 27, 2019

Rebecca Morrison Department of Computer Science, University of Colorado Boulder Representing model error in reduced models of interacting systems In many applications of interacting systems, we are only interested in the dynamic behavior of a subset of all possible active species. For example, this is true in combustion models (many...

## Joint APPM/MATH Colloquium - Catherine Sulem

Sept. 24, 2019

Catherine Sulem Department of Mathematics, University of Toronto Bloch theory and spectral gaps for linearized water waves We consider the movement of a free surface of a two-dimensional fluid over a variable bottom. We assume that the bottom has a periodic prole and we study the water wave system linearized...

## Stats, Optimization, and Machine Learning Seminar - Zhishen Huang and Antony Pearson

Sept. 23, 2019

Zhishen Huang Department of Applied Mathematics, University of Colorado Boulder Finding local minimizers in nonconvex and non-smooth optimization We consider the problem of finding local minimizers in nonconvex and non-smooth optimization. The objective function we consider is in the form of the sum of a nonconvex function and a l1-penalty...

## Applied Math Colloquium - John Harlim

Sept. 20, 2019

John Harlim Departments of Mathematics and Meteorology, Penn State University Manifold learning based computational methods Recent success of machine learning has drawn tremendous interests in applied mathematics and scientific computations. In this talk, I will discuss recent efforts in using manifold learning algorithms (a branch of machine learning) to do...

## APPM Instructor Candidate - Brett Werner

Sept. 19, 2019

Brett Werner Department of Mathematics, University of Colorado Boulder On Machine Learning Machine learning (ML) is the process of making computers learn without specifically programming them to do so. ML has a variety of applications including predicting revenue, detecting credit card fraud, and self-driving cars. We will begin by discussing...

## Math Bio Seminar - Jacqui Wentz

Sept. 17, 2019

Jacqui Wentz Department of Applied Mathematics, University of Colorado Boulder Singular value decomposition of the reaction-diffusion stoichiometry matrix Flux balance analysis (FBA) is a mathematical technique used to study biochemical networks. In contrast to other methods, FBA requires limited information about kinetic parameters and metabolite concentrations. Previously, we developed a...