Infosheet (January 10th, 2017) |
Queen's University - Department of Mathematics and Statistics |
Friday, January 13 |
Number Theory Seminar Time: 10:30 a.m. Place: Jeffery 422 |
Speaker: Siddhi Pathak Title: On the transcendental nature of certain generalized Euler-Lehmer constants Abstract Attached |
Friday, January 13 |
Department Colloquium Time: 3:30 p.m. Place: Jeffery 234 |
Speaker: Felicia Magpantay, University of Manitoba Title: Mathematics of imperfect vaccines Abstract Attached |
Monday, January 16 |
Department Colloquium Time: 4:30 pm Place: Jeffery 234 |
Speaker: Evan Gawlik, University of California San Diego Title: Numerical Methods for Partial Differential Equations on Evolving Domains Abstract Attached |
Items for the Info Sheet should reach Anne ( burnsa@queensu.ca) by noon on Monday. The Info Sheet is published every Tuesday.
Friday, January 13, 10:30 a.m. Jeffery 422 - Number Theory Seminar
Speaker: Siddhi Pathak
Title: On the transcendental nature of certain generalized Euler-Lehmer constants
Abstract: In this talk, we present a conditional result about the arithmetic nature of generalized Euler Lehmer constants, \gamma_1(a,p) for a between 1 and p -1, when p is an odd prime greater than 5. This is joint work with Prof. Ram Murty.
Friday, January 13, 3:30 p.m. Jeffery 234 - Department Colloquium
Speaker: Felicia Magpantay
Title: Mathematics of imperfect vaccines
Abstract: The dynamics of vaccine-preventable diseases depend on the underlying disease process and the nature of the vaccine. In this talk I will present a general model of an imperfect vaccine and the epidemiological consequences of different modes of vaccine failure. In particular, these can have contrasting effects on disease prevalence and transient solutions, especially after the start of mass vaccination programs. I will also present an application to pertussis, a childhood disease that was once considered a candidate for eradication. This highly infectious disease is still a significant cause of child mortality in the world, and has been reemerging in some countries that maintain high vaccination coverage (e.g. USA, UK). Recent events have highlighted how much we still do not know about the mechanics of this disease and the type of immunity rendered by infection and vaccination. I will discuss the theoretical analysis that led us to a general stochastic model of pertussis, and the ideas behind the likelihood-based statistical inference methods (trajectory matching and iterated filtering) used to efficiently estimate the parameters of the model. The methods used can be extended to study and fit mechanistic models of complex phenomenon beyond those in disease ecology.
Monday, January 16, 4:30 p.m. Jeffery 234 - Department Colloquium
Speaker: Evan Gawlik
Title: Numerical Methods for Partial Differential Equations on Evolving Domains
Abstract: Many important and challenging problems in computational science and engineering involve partial differential equations with a high level of geometric complexity. Examples include moving-boundary problems, where the domain on which a PDE is posed evolves with time in a prescribed fashion; free-boundary problems, where the domain is one of the unknowns in and of itself; and geometric evolution equations, where the domain is an evolving Riemannian manifold. Such problems are inherently challenging to solve numerically, owing not only to the difficulty of discretizing functions defined on evolving geometries, but also to the coupling, if any, between the geometry’s evolution and the underlying PDE. Similar difficulties, which are in some sense dual to those just mentioned, are faced when the goal is to numerically approximate functions taking values in a manifold. This talk will focus on tackling these unique challenges that lie at the intersection of numerical analysis, PDEs, and geometry.