Joint AWM-MOCA Speaker Series


Iowa State’s MOCA group and AWM student chapter are collaborating to host the Joint AWM-MOCA Speaker Series (JAMSS). With support from the Department of Mathematics, the College of Liberal Arts and Sciences, and the Graduate College, JAMSS will host the following four speakers from underrepresented groups in mathematics in order to connect women and minority students in the graduate program with a variety of successful underrepresented mathematicians in the field.

Each speaker will give a talk at the department of mathematics colloquium at 4:10pm on the Tuesday of their visit. Additionally, our groups will host a lunch with interested students and faculty during which the speaker will lead an informal discussion about their career path and how their status as an underrepresented mathematician has impacted them. Students and faculty interested in meeting one-on-one with a speaker should contact us at jamss@iastate.edu.


Naiomi Cameron

Lewis & Clark College

Date: October 9, 2018

Website: https://sites.google.com/a/lclark.edu/ncameron/

Title: Inversion generating functions for signed pattern avoiding permutations


Abstract: We consider the classical Mahonian statistics on the set B_n(\Sigma) of signed permutations in the hyperoctahedral group B_n which avoid all patterns in \Sigma, where \Sigma is a set of patterns of length two. In 2000, Simion gave the cardinality of B_n(\Sigma) in the cases where \Sigma contains either one or two patterns of length two and showed that |B_n(\Sigma)| is constant whenever |\Sigma|=1, whereas in most but not all instances where |\Sigma|=2, |B_n(\Sigma)|=(n+1)!. We answer an open question of Simion by providing bijections from B_n(\Sigma) to S_{n+1} in these cases where |B_n(\Sigma)|=(n+1)!. In addition, we extend Simion's work by providing a combinatorial proof in the language of signed permutations for the major index on B_n(21, \bar{2}\bar{1}) and by giving the major index on D_n(\Sigma) for \Sigma ={21, \bar{2}\bar{1}} and \Sigma={12,21}. The main result of this paper is to give the inversion generating functions for B_n(\Sigma) for almost all sets \Sigma with |\Sigma|\leq 2.







Marta D'Elia

Sandia National Laboratories

Date: November 6, 2018

Website: https://sites.google.com/site/martadeliawebsite/

Title: Nonlocal models in computational science and engineering: challenges and applications


Abstract: Nonlocal continuum theories such as peridynamics and nonlocal elasticity can capture strong nonlocal effects due to long-range forces at the mesoscale or microscale. For problems where these effects cannot be neglected, nonlocal models are more accurate than classical Partial Differential Equations (PDEs) that only consider interactions due to contact. However, the improved accuracy of nonlocal models comes at the price of a computational cost that is significantly higher than that of PDEs. In this talk I will present nonlocal models and the Nonlocal Vector Calculus, a theory that allows one to treat nonlocal diffusion problems in almost the same way as PDEs.
Furthermore, I will present current open challenges related to the numerical solution of nonlocal problems and show how we are currently addressing them. Specifically I will describe an optimization-based local-nonlocal coupling strategy and briefly introduce a technique to improve the performance of Finite Element (FE) approximations.
The goal of local-nonlocal coupling methods is to combine the computational efficiency of PDEs with the accuracy of nonlocal models. These couplings are imperative when the size of the computational domain or the extent of the nonlocal interactions are such that the nonlocal solution becomes prohibitively expensive to compute, yet the nonlocal model is required to accurately resolve small scale features. Our approach formulates the coupling as a control problem where the states are the solutions of the nonlocal and local equations, the objective is to minimize their mismatch on the overlap of the nonlocal and local domains, and the controls are virtual volume constraints and boundary conditions. I will present consistency and convergence studies and, using three-dimensional geometries, I will also show that our approach can be successfully applied to challenging, realistic, problems.
Finally I will introduce a new concept of nonlocal neighborhood that helps improving the performance of FE methods and show how our approach allows for fast assembling in two- and three-dimensional computations.

Speaker TBA

Institution TBA

Date: Spring, 2019

Website:

Title: TBA


Abstract: TBA

Mark Lewis

Institution TBA

Date: April 9, 2019

Website: https://people.orie.cornell.edu/melewis/

Title: TBA


Abstract: TBA

About AWM

The Association of Women in Mathematics (AWM) is a non-profit organization formed to encourage women and girls to study and to have active careers in the mathematical sciences, and to promote equal opportunity and the equal treatment of women and girls in the mathematical sciences. The Iowa State AWM Student Chapter organizes social events to promote a sense of community, formal events to discuss the AWM mission, and outreach events to help the local community.

About MOCA

The Mathematicians of Color Alliance (MOCA) is a group of minority graduate and undergraduate mathematics students whose goal is recruitment, retention, and the mentoring of underrepresented students by creating a presence in the department, on campus, and around the nation. MOCA organizes various activities to promote diversity as well as hosting social events to foster a sense of community among ourselves and the wider undergraduate and graduate math communities.

Websites from previous years: 2017-18