Thursday, March 29th
Speaker : James J. Riley, UW ME
Title : On the kinematics of flame surfaces in a turbulent flow
Abstract : An important aspect of the dispersive influence of turbulent flows is their ability to rapidly increase the area of fluid surfaces. An example of such a surface is the stoichiometric surface in a non-premixed, chemical reaction, which approximates the flame surface. The stoichimetric surface can itself be approximated by a surface of constant value of a passive scalar, the mixture fraction. In this presentation results will be presented for the growth and decay of iso-surfaces in turbulent flow. Direct measurements of iso-surfaces from numerical simulation will be presented, along with their indirect measurement using Rice's theorem (1944). This theorem leads to two separate modeling approaches to predict the evolution of the iso-surfaces. Comparisons of the predictions of these models with simulation results will be presented.

Thursday, April 5th
Speaker : Laura Matrajt, Department of Medicine, UW/ Fred Hutchinson Cancer Research Center
Title : Optimal vaccine distribution through a network of cities in an influenza pandemic
Abstract: With new cases of avian influenza H5N1 arising frequently, the threat of a new influenza pandemic remains a challenge for public health. Because there is an important time lag between the emergence of a new pathogen and the development of a vaccine, shortage of vaccine is very likely to occur at the beginning of a pandemic. In the present work, we coupled a mathematical model with a genetic algorithm to optimally and dynamically distribute vaccine in a network of cities, connected by the airline transportation network. Our model allows for multiple vaccination times, both before and during an epidemic in a city. Because most of the human cases of avian influenza H5N1 have arisen in South East Asia, we used a network of 16 cities in this region as a testbed scenario. Our results allowed us to quantify the possibility of stopping an epidemic with a given quantity of vaccine. We also established useful comparisons between optimal solutions and the current guidelines for vaccine distribution. In particular, we showed that our optimal allocation always outperforms current vaccine distribution policies.

Thursday, April 12th
Speaker: Christopher Jones, UW AMATH/ATMOS
Title : Modeling the response of marine boundary layer clouds to climate change
Abstract: The representation of marine boundary layer (MBL) clouds in global climate models (GCMs) is a primary source of uncertainty in model predictions of how much the Earth's temperature will rise in response to global warming. A key limitation is a lack of understanding of the physical mechanisms responsible for low cloud response to climate change. Insight into these physical mechanisms is crucial for improving the parameterizations of cloud processes in GCMs, and decreasing the inter-model spread in climate sensitivity. In this talk, I will provide an overview of MBL clouds, their role in the Earth's climate, and how a hierarchy of models of varying complexity can be used to investigate their response to global warming. (slides)

Thursday, April 19th
Speaker : Anne Greenbaum, UW AMATH
Title : An Introduction to Multigrid Methods
Abstract:

Thursday, April 26th
Speaker : Jim Morrow, UW MATH
Title : Undergraduate Research and Competition Opportunities
Abstract: Undergraduate research is encouraged and supported in the Math Department: Grant support is available to support work with individual faculty during the academic year. There is also a summer REU program in which students work full time on projects with faculty and TAs. There is also an opportunity to compete in the Mathematical Contest in Modeling. We have been very successful in this competition. Another activity that undergrads are encouraged to be part of is Mathday.

Thursday, May 3rd
Speaker : Anne Greenbaum, UW AMATH
Title : Mathematical Modeling of Collapsing Bridges
Abstract:

Thursday, May 10th
Speaker : Emo Todorov, UW AMATH/CSE
Title : Automatic synthesis of complex behaviors with optimal control (slides)
Abstract :

Thursday, May 17th
Speaker : Christopher Swierczewski, UW AMATH
Title : A Sample of Scientific Computing in Python
Abstract: Python is popular programming language amongst mathematicians and scientists for doing open-source scientific programming. In this talk we will experience a sample of the scientific tools available in the Python language such as the Enthought Python Distribution (EPD) and Sage as well as some mathematical problems that these tools can solve. If you like, come prepared by downloading and installing the Enthought Python Distribution and Sage.

Thursday, May 24th
Speaker : Duane Storti, UW ME
Title : Modeling based on 3D imaging using Wavelets and Parallel Computing on the GPU
Abstract: Traditional computer-aided design (CAD) software describes an object as a collection of trimmed parametric surface patches that cover the object's boundary. This traditional approach fails to take advantage of new capabilities made available by 3D printing and makes it extremely tedious to create models of objects acquired by volumetric (CT or MRI) scans. This talk will present an alternative approach to solid modeling that describes objects implicitly and show how the implicit method is extended to readily handle scanned objects (by using wavelets to interpolate a segmentation by-product) as well as objects created in traditional CAD systems. The new modeling techniques are well-suited to parallelism, and a demonstration will show that the level of general purpose parallel computing available on a laptop computer is sufficient to support real-time modeling with wavelet interpolants.

Thursday, May 31st
In addition to our speaker for the day, Professor Anne Greenbaum will present the Herbert L. Costner award for outstanding research by an ACMS student to Mary Salcedo. This will be followed by a short talk by Ms. Salcedo on her work.

Speaker : Mark Kot, UW AMATH
Title : Mathematical Models for Biological Invasions and for the Effects of Climate-Change-Driven Range Shifts
Abstract: Biological invasions can have dramatic ecological and economic consequences. Thus, there is keen interest in models that correctly predict rates of spread of invading organisms. Traditional reaction-diffusion models that generate traveling waves of invasion often underestimate true rates of invasion. In contrast, integrodifference equations (IDEs) often give better estimates; they also resolve important paradoxes in the theory of invasions. Recently, IDEs have also been used to predict the effects of climate-change-driven species range shifts. In this talk, I discuss the formulation and analysis of IDEs and look at the use of these equations for modeling biological invasions and the effects of global climate change.

For information on the Applied and Computational Math Sciences (ACMS) Degree at the UW, click here: ACMS Website
Please send comments, corrections, and suggestions to: greenbau[at]math[dot]washington[dot]edu or vvasan[at]u[dot]washington[dot]edu.