New Applied Mathematics Faculty Members: Tippett and Létourneau

The APAM Department is pleased to welcome two new Applied Mathematics faculty members.

Dr. Michael Tippett is a new Lecturer in the Discipline of Applied Mathematics.

Dr. Tippett’s research focuses on the use and development of mathematical approaches to characterize the variability and predictability of the climate system on a range of time-scales, from decadal variability of sea surface temperatures to seasonal drought, with emphasis on date-driven methods. Much of his work uses empirical, low-dimensional descriptions of predictable components of the climate system. Most recently, he has been investigating with Prof. Adam Sobel the extent to which slow time-scale climate variability constrains the statistics of weather extremes, an issue of considerable societal interest with important implications for projections and predictions of future climate. They have demonstrated for the first time that monthly U.S. tornado activity can be predicted as much as one month ahead of time, and this work is being continued in collaboration with partners from the National Weather Service and the insurance industry.

He received Bachelor’s degrees in Electrical Engineering and Mathematics from North Carolina State University and an M.Sc. and Ph.D. from the Courant Institute of Mathematical Sciences at New York University. Tippett is teaching APMA E3101: Linear Algebra.

Dr. Pierre-David  Létourneau is the new Chu Assistant Professor of Applied Mathematics.

Dr.  Létourneau received his Ph.D. in Applied Mathematics from Stanford University in 2013, under the supervision of Prof. Eric Darve and Prof. George Papanicolaou, and was the recipient of the Juan Simo Outstanding Thesis Award. His work was mostly concerned with the study of waves in random media. In particular, he theoretically analyzed and subsequently developed an algorithm together with a piece of software capable of simulating the propagation of acoustic waves in highly heterogeneous media. Such media include, for example, those constituted by a large amount of air bubbles in water and are known to present substantial computational difficulties. His past research also involved the development of a scheme generalizing the application of fast algorithms (methods for the accelerating dense linear algebra operations) to a larger classes of problems, the construction of generalized Gaussian quadrature, imaging in highly heterogeneous media as well as seismic imaging.

His current focus lies with the study of inverse problems associated with waves in complex media. Some of his current projects involve hybrid imaging problems (where various physical phenomenon are present; with Prof. Guillaume Bal) and the calculation and understanding of the scattering signature from Q-dot structures (with Prof. I.C. Noyan). He is also in the process of developing an algorithm capable of simulating the propagation of linear elastic waves in highly heterogeneous media which he plans to use to study numerically and theoretically the problem of imaging of small bodies embedded in an elastic media (with Prof. Mourad Sini, AAS, Linz, Austria).

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