Mathematical Application Seminar
Spring 2008
Mondays 11:10 – 12:10pm.
Monroe Hall,
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February 4, 2008, Monday 11:10
– 12:10pm
Speaker: Xianfeng David Gu (CS dept,
Title: Computational Conformal Geometry, Algorithms and
Applications
Place: Monroe Hall,
Abstract: Computational conformal geometry is an
interdisciplinary field,
combining modern
geometry theories from pure mathematics with computational
algorithms from
computer science. Computational conformal geometry offers
many powerful tools to
handle a broad range of geometric problems in
engineering fields.
This work summarizes our research results in the past
years. We have
introduced efficient and robust algorithms for computing
conformal structures
of surfaces acquired from the real life, which are
based on harmonic
maps, holomorphic differential forms and surface
Ricci
flow. We have applied
conformal geometric algorithms in computer graphics,
computer vision,
geometric modeling and medical imaging.
February 11, 2008, Monday
11:10 – 12:10pm
Speaker: E. Arthur Robinson (Math Dept, GWU)
Title: An introduction to the use of algebraic statistics
in modeling
biological sequence data.
Place: Monroe Hall,
Abstract: We discuss the method of algebraic statistics, which
uses computational
algebraic geometry (e.g., Groebner bases) to model DNA and RNA sequences.
This idea was pioneered by Lior Pachter and Bernd Sturmfels. The talk is expository.
It will cover the basic
ideas behind this method and consider some simple examples.
February 18, 2008, President’s Day. GWU is closed.
No talk scheduled.
(A previously scheduled talk
by Teresa Przytycka is rescheduled to be on March 3).
February 25, 2008, Monday
11:10 – 12:10pm
Speaker: Li Chen (UDC, CS Dept)
Title: Connectedness in digital space
Place: Monroe Hall,
Abstract: This talk will begin with an overview on
digital geometry, digital space connectivity,
and digital objects such as
digital curves and surfaces. Then we will focus on digital
functions and connectedness.
In addition, the necessary and sufficient condition for
the existing measure
regarding to connectedness will be presented. We will also explore
related topics including the
digitally "continuous" parts, graph-based spanning trees,
and the maximum
connectedness. Finally, we will discuss some applications of
connectedness to image
segmentation.
March 3, 2008, Monday
11:10 – 12:10pm
Speaker: Teresa Przytycka, NIH | NLM
| NCBI
Title: Towards uncovering connections between
graph-theoretical properties of nodes in
protein interaction network and their biological essentiality.
Place: Monroe Hall,
Abstract: An intriguing question in the analysis of biological
networks is whether biological
characteristics of a
protein, such as essentiality, can be explained by its placement in the
network,
i.e., whether topological
prominence implies biological importance. One of the first connections
between the two in the
context of a protein interaction network, the so-called centrality-lethality
rule,
was observed by Jeong and colleagues (Jeong et
al. 2001) who demonstrated that high-degree nodes
or hubs in a protein
interaction network of Saccharomyces cerevisiae contain more essential proteins
than would be expected by
chance. Even though the correlation between degree and essentiality was
confirmed by many
independent studies, the reason for this correlation remains illusive.
I will discus several
hypotheses about putative connections between essentiality of hubs and the
topology of protein-protein
interaction network that have been proposed recently and demonstrate
that these explanations are
not always supported by the properties of protein interaction networks.
I will also discuss an
alternative explanation.
March 10, 2008, Monday
11:10 – 12:10pm
Speaker: Sudip Bose (GWU, Statistics Department)
Title: Methods of algebraic geometry in biology and
statistics
Place: Monroe Hall,
Abstract: This is an expository talk about the uses of
computational commutative algebra (CCA)
in biology, statistics and
related fields. As a simple example, one may note that
the probability distribution
from the Hardy-Weinberg principle in genetics can be viewed
as an algebraic
variety. The work of Diaconis and Sturmfels in the early 90s applied
Buchberger's methods to contingency tables. Pistone and Wynn demonstrated the use
of CCA in design of
experiments. The study of Boolean algebras leads to
applications in modeling
biological systems, and in reliability. In fact, rings and ideals
arise naturally in the study
of probability distributions and standard statistical models.
The focus of the talk will
be on the connections rather than specific details of the
application of, say, Grobner bases, to the solution of optimization problems in
statistics and biology.
March 17, 2008. GWU pring break.
No seminar.
March 24, 2008, Monday
11:10 – 12:10pm
Speaker: Ken Shaw (ONR)
Topic: Compressive Sampling
Reference: http://www.dsp.ece.rice.edu/cs/
Place: Monroe Hall,
Abstract: This is an expository lecture on the subject of
compressive sampling (CS),
also known as compressive
sensing, sparse sensing or sparse sampling. CS is a priority
research area for
surveillance and homeland security purposes because of its potential to
help cope with large streams
of data. Indeed, the real promise of CS lies not in data
reduction but sparse signal
construction through adroit under-sampling.
The field is an attractive
combination of mathematical optimization and probability.
Typical results involve
convex minimization problems whose solutions are exact –
with "high probability."
The talk intends to survey the field and point out some prospective
research problems. It will
be accessible to a general mathematical audience.
Brief biographical
sketch: Ken Shaw is an emeritus
professor of mathematics at
Virginia Tech and until
March 1, 2008, was a program officer at the Office of Naval Research.
He was a program officer in
applied mathematics at the National Science Foundation
between 2002 and 2005.
During the academic years 2005-2007 he served as director
of operations for the
graduate program in mathematics and statistics at
and is currently an
Affiliated Faculty member in mathematics at
April 14, 2008.
No talk scheduled.
(A previously scheduled talk
by Susan Cheng (CS Dept, GWU) will be rescheduled in Fall 2008)
April 21, 2008
No talk scheduled due to
a thesis defense
Speaker: Hosam Mahmoud
(GWU, Statistics Department)
Title: Algorithmic and mathematical issues in pattern
matching
Place: Monroe Hall,
Abstract: The speaker will present some of his own results in
pattern matching
in strings, and more complex
combinatorial structures such as random trees. The
intent is to give the
audience an idea about the algorithmic and combinatorial
issues involved, and
the flavor of the associated results (such as approximating
exact discrete distributions
by continuous limits like the Gaussian and mixed normal
distributions). The talk is
intended to a broad audience of scientists, specially
biologists interested in
mathematical models, and the speaker will try to sketch the results
while staying away from
technically involved proofs.
_________________________________________________________________________
Some future speakers
(subject to confirmation)
Christian Laing (NYU)
Rahul Simha (GWU, CS)
Chen Zeng
(GWU, bio-physics)
Speaker: Xiuzhen (Susan) Cheng (CS
Dept, GWU) http://www.seas.gwu.edu/~cheng
Topic: Connected dominating set and its applications in
wireless networks.
Place: Monroe Hall,
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