Seminars and Colloquiums
for the week of April 5, 2010
Speaker:
Mr. Zhiqiang Li, Monday
Mr. Chad Kilpatrick, Wednesday
Mr. Keith Penrod, Friday
Dr. Aparna Higgins, University of Dayton, Friday
Monday, April 5
PROBABILITY SEMINAR
TIME: 10:10 – 11:00 a.m.
ROOM: AC 113
SPEAKER: Mr. Zhiqiang Li
TITLE: "UNIFORM CONVERGENCE OF A BRANCHING PARTICLE FILTER."
ABSTRACT: Recently, various particle filters have been proposed and their convergence to the optimal filter studied. Most of the convergence results obtained are for finite time intervals. Some uniform convergence results for discrete time filters are established by some authors. In this paper,
we prove the uniform convergence of a branching particle filter for continuous time setup when the optimal filter itself is exponentially stable.
Wednesday, April 7
COARSE GEOMETRY SEMINAR
TIME: 11:15 – 12:05 p.m.
ROOM: Temple 303
SPEAKER: Mr. Chad Kilpatrick
TITLE: “Property A is Equivalent to Nuclearity and Exactness for Countable
Discrete Groups G” VI
ABSTRACT: In this talk, we will see that for a countable discrete group G, property A is equivalent to:
1. Cr*(G) is exact
2. Cu*(G) is nuclear
3. Cu*(G) is exact.
Here, a C*-algebra A is defined to be nuclear if for any finite subset F of A, the identity map may be approximated on F by unital completely positive maps which factorize through Mn(C), for some n. In this talk, I closely follow Ch. 4: "Connections with C*-Algebras” from
Rufus Willet’s Some Notes on Property A.
Friday, April 9
TOPOLOGY SEMINAR
TIME: 11:15 – 12:05 p.m.
ROOM: Temple 303
SPEAKER: Mr. Keith Penrod
TITLE: “Group actions on metric and topological spaces II”
ABSTRACT: The material is based on Chapter 8 from the book by Bridson and Haefliger (Metric spaces of non-positive curvature).
JUNIOR COLLOQUIUM
TIME: 3:35 p.m.
ROOM: HBB 102
SPEAKER: Dr. Aparna Higgins, University of Dayton
TITLE: “Pebbling and defense strategy”
ABSTRACT: We describe an application of pebbling on graphs to defense strategy. When deploying troops, it is important to ensure that the force that arrives at a trouble spot is large enough to deal with the trouble effectively. Each move made by troops has a cost associated with it. It is desirable to Move as many troops as necessary while keeping the costs as low as possible. Viewing regions of the globe as nodes of a graph, where proximate regions are joined by an edge, we can move pebbles
(representing troops) between regions according to certain rules, assessing a cost for each move made. We compare certain common strategies, such as defense-in-depth and deterrence, and provide a hypothetical explanation for the fall of the Roman Empire.
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. Steve Wise.
Week of:
3_8_10.html (spring break)
Past notices:
Seminars from 2008-2009 academic year
Seminars from 2007-2008 academic year
Seminars from 2006-2007 academic year