Seminars and Colloquia

Upcoming Seminars

CAMS Seminar
3:30-4:30 PM every other Monday (starting 9/18/17), 103 Centennial Hall

Hyperspace and Topology Seminar
3-5 PM on selected Wednesdays, Rolla G5
10:50 AM-12:20 PM on selected Thursdays, Rolla G4

Real Analysis Seminar
3:30-4:30PM every other Monday (starting 9/25/17), 103 Centennial Hall

Time Scales Seminar
3:00-3:50 PM every Wednesday, Rolla G4

Ingram Lectureship

After he retired following the Fall 2002 semester, Professor W.T. Ingram, who was department chair from 1989-1998, generously set up an endowed fund to be used to bring well-known mathematical scientists to Rolla to give lectures on their work.  All Ingram Lectures are open to the entire S&T community, and are widely advertised on campus.  Visitors brought here under this program usually give two lectures, one of a general nature and accessible to students, and another more advanced aimed at faculty (though students are certainly welcome).

Presentations of Ingram Lectureship

Fall 2017 Colloquia

Group Sparsity via Approximated Information Criteria

Nan Lin
Associate Professor
Department of Mathematics,
Department of Biostatistics,
Washington University in St. Louis

Thursday, October 4, 2017
4:00-5:15 PM
Rolla Bldg G-5

We propose a new group variable selection and estimation method, and illustrate its application for the generalized linear model (GLM). This new method, termed “gMIC”, was derived from approximating the information criterion by a smooth unit dent function. The gMIC is derived as a smooth approximation of a group-version modification of the information criterion. The approximated information criterion is further reparameterized in a way that not only renders sparse estimation from a smooth programming problem but also facilitates a convenient way of circumventing post-selection inference. Compared to existing group variable selection and estimation methods, the gMIC is free of parameter tuning and hence computationally advantageous. We also establish the oracle property of the proposed method that is supported by both simulation studies and real examples. 

Nan Lin, PhD, is currently an associate professor of Statistics at the Dept. of Mathematics, and Dept. of Biostatistics, Washington Univ. in St. Louis. He obtained his PhD in statistics from University of Illinois at Urbana-Champaign in 2003. Before joining Washington University, he was a postdoctoral associate at the Center for Statistical Genomics and Proteomics, Yale University. His methodological research is in the areas of statistical computing for massive data, Bayesian regularization, bioinformatics, longitudinal and functional data analysis and psychometrics. His applied research involves statistical analysis of data from anesthesiology, genomics and cognition. He was awarded "The most promising paper published in Bayesian Analysis in the last five years, The International Society for Bayesian Analysis" in 2016. 

 Host:  Wen

Asymptotic behavior for the nonlinear Schrödinger equation with critical homogeneous nonlinearity

Satoshi Masaki
Associate Professor
Department of Systems Innovation
Graduate School of Engineering Science
Osaka University

Friday, September 22, 2017
4:00-5:15 PM
Rolla Bldg G-5

We will consider asymptotic behavior of solutions to nonlinear Schrödinger equations with a homogeneous nonlinearity of critical degree. It was previously known that for the critical case, the possible asymptotic behavior heavily depends on the shape of nonlinearity. In this talk, we consider general homogeneous nonlinearities including the non-polynomial case and discuss how to determine the behavior. We also discuss an application to Klein-Gordon equation.

Dr. Masaki earned his PhD in Mathematics from Kyoto University in the Spring of 2009 under the supervision of Yoshio Tsutsumi. He began his career at Gakushuin University in Spring 2010 as an Assistant Professor. In Fall 2012, he moved to Hiroshima University as an Associate Professor. Since Spring 2016, he has been an Associate Professor at Osaka University. Dr. Masaki's main research interests lie in the areas of harmonic analysis and nonlinear dispersive equations, with a primary focus on the asymptotic behavior of solutions to nonlinear Schrödinger equations.

 Host:  Murphy

On a modification of the Schur algorithm that leads to linear pencils of difference operators

Maksym Derevyagin
Visiting Assistant Professor
Department of Mathematics
University of Mississippi

Friday, September 15, 2017
4:00-5:15 PM
Rolla Bldg G-5

The Schur algorithm is one of the key ingredients of the theory of orthogonal polynomials on the unit circle.  It is worth noting that the theory of orthogonal polynomials on the unit circle has witnessed a great development since the beginning of the century due to an enormous contribution by Barry Simon. However, the modification we are going to discuss was implicitly introduced by H.S. Wall in 1944 and it can be thought of as a transform between Schur functions, Carathéodory functions, and Herglotz-Nevanlinna functions. At the same time, this transformation provides us with a bijection between orthogonal polynomials on the unit circle and some new objects on the real line. More precisely, it will be shown that, when applying the Wall transformation, instead of orthogonal polynomials on the real line, we get a sequence of orthogonal rational functions that satisfy three-term recurrence relation of the form (H−λJ)u=0, where u is a semi-infinite vector, whose entries are rational functions. Besides, J and H are Hermitian Jacobi matrices for which a version of the Denisov-Rakhmanov theorem holds true.

 Host:  Clark

Past Colloquia

For past colloquium information, click here