Seminars and Colloquiums
for week of September 26, 2011
Speaker:
Dr. Cory Hauck, ORNL, Monday
Professor Jie Xiong, Monday
If you are interested in giving or arranging a talk for one of our seminars or colloquiums,
please review our calendar.
If you have questions, or a date you would like to confirm, please contact Dr. Judy Day.
Monday, September 26, 2011
DE and Applied/Computational Math Seminar
TIME: 3:35 – 4:25pm
ROOM: Ayres 113
SPEAKER: Dr. Cory Hauck, ORNL
TITLE: A Realizability-Preserving, Discontinuous Galerkin Scheme for the $M_1$ Model of Radiative Transfer
ABSTRACT: The $M_1$ model is a hyperbolic balance law which approximates the flow of radiation through a material medium. It is a moment model which is derived from an underlying kinetic description via a constrained, convex optimization problem. For the model to be well-defined, the moments must satisfy so-called realizability conditions which ensure that the optimization problem has a solution. Because standard discontinuous Galerkin (DG) methods do not preserve realizability, this property must be built in. To this end, we adopt and apply the recent positivity-preserving limiting technique of Zhang and Shu to derive a high-order, Runge-Kutta DG (RKDG) scheme for the $M_1$ model that preserves realizability. In this talk, we give some introduction to the $M_1$ model, describe the limiting technique and its application, and then present results for several one-dimensional test cases.
Probability Seminar
TIME: 3:35 – 4:25
ROOM: Ayres 122
SPEAKER: Professor Jie Xiong
TITLE : Uniqueness problems for some measure-valued processes
ABSTRACT: A stochastic partial differential equation (SPDE) is derived for the super Brownian motion regarded as a distribution function valued process. The strong uniqueness for the solution to this SPDE is obtained by a connection between SPDEs and backward doubly stochastic differential equations. Similar results are also proved for the Fleming-Viot process.
Past notices:
Seminars from 2010-2011 academic year
Seminars from 2009-2010 academic year
Seminars from 2008-2009 academic year
Seminars from 2007-2008 academic year
Seminars from 2006-2007 academic year