## Math Colloquium

Each semester the Department of Mathematics offers colloquium talks on a variety of mathematical topics. The department also hosts the Advanced Research Initiative series, featuring a distinguished guest speaker giving two talks. For upcoming Math Colloquia please see the Department of Mathematics Events Calendar.

2018 Spring

### 2018 Spring Math Colloquia

February 21
Michael Otunuga (Marshall University)
Global stability for a (2n+1)-dimensional HIV/AIDS epidemic model with treatments
Smith Hall 518, 4:00pm

Abstract: In this work, we derive and analyze a (2n+1)-dimensional deterministic differential equation modeling the transmission and treatment of HIV (Human Immunodeficiency Virus) disease. The model is extended to a stochastic differential equation by introducing noise in the transmission rate of the disease. A theoretical treatment strategy of regular HIV testing and immediate treatment with Antiretroviral Therapy (ART) is investigated in the presence and absence of noise. By defining R(0,n), R(t,n) and R(t,n) as the deterministic basic reproduction number in the absence of ART treatments, deterministic basic reproduction number in the presence of ART treatments and stochastic reproduction number in the presence of ART treatment, respectively, we discuss the stability of the infection-free and endemic equilibrium in the presence and absence of treatments by first deriving the closed form expression for R(0,n), R(t,n) and R(t,n). We show that there is enough treatment to avoid persistence of infection in the endemic equilibrium state if R(t,n)=1. We further show by studying the effect of noise in the transmission rate of the disease that transient epidemic invasion can still occur even if R(t,n)<1. This happens due to the presence of noise (with high intensity) in the transmission rate, causing R(t,n)>1. A threshold criterion for epidemic invasion in the presence and absence of noise is derived. Numerical simulation is presented for validation.

March 28
Elizabeth Niese (Marshall University)
Title to be announced
Smith Hall 518, 4:00pm

Abstract: To be announced

April 19
Carl Mummert (Marshall University)
Title to be announced
Smith Hall 518, 4:00pm

Abstract: To be announced

2017 Fall

### 2017 Fall Math Colloquia

September 20
Matt Davis (Muskingum University)
Non-transitive dice: Constructions, Complications, and Questions
Smith Hall 509, 4:00pm

Abstract: Non-transitive dice have been a source of fascination for mathematicians for over 50 years. We are given a set of dice which are numbered in strange ways. Each player chooses a die, rolls it, and the higher roll wins. Our intuition suggests that in any set of dice, one is the “best”. However, it turns out that it is relatively easy to construct a set of dice which are non-transitive – where most dice are strong against some opponents and weak against others. In this talk we will look at lots of examples of these fascinating objects, aiming for a goal of a single construction that allows us to create a set of dice in any desired configuration. We will also talk briefly about the much harder problem of finding the most efficient way to create such a set of dice.

October 18
Skye Smith (Service Pump & Supply, Huntington WV)
Three Things I Wish I Had Known When I Was a Math Major
Smith Hall 509, 4:00pm

Abstract: Since graduating from Marshall University with an applied mathematics degree in 2014, I have used my degree in several various business roles. Each position has provided a new way to use my mathematics degree in a business setting and each role brought new lessons I wished I had considered throughout my time as an undergraduate student. In this presentation, I will discuss the three things I wish I had known while I was a mathematics major at Marshall University. Addressing these three observations will help guide mathematics students who are hoping to use their skill set in a business setting at a time when math minds are more important than ever to companies undergoing digital transformations and embracing the era of big data.

November 15
Avishek Mallick (Marshall University)
Statistical Modeling of Discrete/Count Data

Abstract: In this talk, I will introduce the idea of Statistical modeling, especially in context of count data. We will look at different facets of data fitting like estimation techniques and criterion for assessing goodness-of-fit. A substantial part of the talk will be about modeling inflated count data. We will be looking at lots of real world examples. This talk is intended for a general audience and thus should be appropriate for Mathematics undergraduate and graduate students.

2017 Spring

### 2017 Spring Math Colloquia

January 16
Carl Mummert (Marshall University)
Mathematical Induction: Through Infinity and Beyond

February 16
John Asplund (Dalton State University)
Vertex Colouring Degeneracy and the Limits of Edge-Colouring Techniques

2016 Fall

### 2016 Fall Math Colloquia

September 21
Michael Schroeder (Marshall University)
A Survey of Graph Decompositions

October 24
Elizabeth Niese (Marshall University)
The combinatorics of symmetric polynomials

November 16
Scott Sarra (Marshall University)
Radial Basis Functions Methods and their Implementation

November 30
JiYoon Jung (Marshall University)

2016 Spring

### 2016 Spring Math Colloquia

January 26
Avishek Mallick (Marshall University)
A Look at Permuatation (a.k.a. Randomization) Tests

February 24
Carl Mummert (Marshall University)
Incompleteness in mathematics

March 7
Shubhabrata Mukherjee (University of Washington, Seattle)
Introduction to Genetic Epidemiology in GWAS era

March 8
Shubhabrata Mukherjee (University of Washington, Seattle)
Genetic analyses of late-onset Alzheimer’s Disease

April 6
Anna Mummert (Marshall University)

2015 Fall

### 2015 Fall Math Colloquia

September 2
Michael Schroeder (Marshall University)
Tournaments: Scheduling Them Fairly and More!

September 28
Nick Loehr (Virginia Tech)
Rook Theory 101

September 29
Nick Loehr (Virginia Tech)
Sweep Maps and Bounce Paths

October 21
Micheal Otunuga (Marshall University)
Stochastic Modeling of Energy Commodity Spot Price Processes

November 4
Martha Yip (University of Kentucky)
Coloring: the Algebraic Way

2015 Spring

### 2015 Spring Math Colloquia

February 4
Elizabeth Niese (Marshall University)
What do trigonometry and combinatorics have to do with each other?

February 17
David Cusick (Marshall University)
350 Years of Service … and Then Pffft!

March 4
Gregory Moses (Ohio University)
Clustering and Stability of Cyclic Solutions in the Cell Division Cycle of Yeast

March 27–28
MAA Ohio Section Meeting at Marshall University

April 14
Judy Day (University of Tennessee)
Modeling the host response to inhalation anthrax to uncover the mechanisms driving risk of disease.

April 15
Judy Day (University of Tennessee)
Determining the what, when, and how of therapeutic intervention strategies for controlling complex immune responses.

2014 Fall

### 2014 Fall Math Colloquia

September 3
Carl Mummert (Marshall University)
Is that a Prime Number?

September 17
Interactive Regression Models with Centering

October 1
Michael Schroeder (Marshall University)
Latin squares and their completions

October 15
Xue Gong (Ohio University)
Clustering and Noise-Induced Dispersion in Cell Cycle Dynamics (No Link to Abstract)

November 5
The Gale-Berlekamp Light-Switching Problem and a Permutation Variation

November 6
All Things Bruhat: Matrix Bruhat Decomposition, Complete Flags, Bruhat Order of Permutations, (0,1) and Integral Matrices, and Tournaments

November 19
Bismark Oduro (Ohio University)
Designing Optimal Spraying Strategies for Controlling Re-infestation by Chagas Vectors

2014 Spring

### 2014 Spring Math Colloquia

March 10
Jeffry L. Hirst (Appalachian State University)

March 11
Jeffry L. Hirst (Appalachian State University)
Reverse Mathematics, Graphs, and Matchings

April 9
JiYoon Jung (Marshall University)
The topology of chain selected complexes of a poset PDF

April 11
Lingxing Yao (Case Western Reserve University)
Mathematical Modeling and Simulation for Biological Applications

April 14
Stephen Flood (University of Connecticut – Waterbury)
Path, trees, and the computational strength of a packed Ramsey’s theorem

2013 Fall

### 2013 Fall Math Colloquia

October 2
Lynne Yengulalp (University of Dayton)
Topological completeness

October 30
Roger Estep (Marshall University)
Filtered leapfrog time integration with enhanced stability properties
Robert Hughes (Marshall)
Agent-based modelin of pandemic influenza

November 18
Thomas Mathew (University of Maryland-Baltimore County)
The Assessment of Bioequivalence: A Statistical Overview

November 19
Thomas Mathew (University of Maryland-Baltimore County)
Methodology and Some Applications

2013 Spring

### 2013 Spring Math Colloquia

January 30
Elizabeth Niese (Marshall)
A family of Catalan objects

February 20
Anna Mummert (Marshall)
Unit costs in optimal control of epidemics

April 24
Carl Mummert (Marshall)
If 1+1=9, does 2+2=7?

2012 Fall

### 2012 Fall Math Colloquia

October 3
John Drost (Marshall)
What is Strategic Voting and What Can Be Done About It?

2012 Spring

### 2012 Spring Math Colloquia

January 25
Michael Schroeder (Marshall)
Cyclic Matching Sequencibility of Graphs

Feburary 22
Anna Mummert (Marshall)
Studying the recovery procedure for the time-dependent transmission rate in epidemic models

March 7
Matthew Sedlock (Johns Hopkins University)
Percolation models

March 9
Avishek Mallick (University of New Hampshire)
Inferential procedures based on samples with nondetects from normal and related distributions

March 12
Myung Soon Song (University of Pittsburgh)
An unconventional approach to likelihood of correlation matrices

April 2
Image quality assessment methods

April 6
JiYoon Jung (University of Kentucky)
The topology of restricted partition posets PDF

2011 Fall

### 2011 Fall Math Colloquia

November 8
Carl Mummert (Marshall)
Two examples from infinitary combinatorics

2011 Spring

### 2011 Spring Math Colloquia

April 5
Suman Sanyal (Marshall)
Stochastic Dynamic Equations

April 8
Elizabeth Niese (Virginia Tech)
Macdonald polynomials and the hook-length formula for standard Young tableaux

April 15
Andrew Oster (École Normale Supérieure)
A laminar model for the development of the primary visual cortex

April 18
Phi-symmetric Hailton cycle decompositions of graphs

April 20
Remy Friends Ndangali (University of Florida)
Bound states in the radiation continuum and nonlinear effects in photonic structures

April 22. Paul Shafer (Cornell)
Coding arithmetic in the Medvedev degrees and its substructures

2010 Fall

### 2010 Fall Math Colloquia

September 8
Anna Mummert (Marshall)
Get the News Out Loudly and Quickly: Modeling the Influence of the Media on Limiting Infectious Disease Outbreaks

October 13
Carl Mummert (Marshall)
The axiom of choice in mathematics and computability

November 9
Suman Sanyal (Marshall)
Stochastic Process Indexed by Time Scale

2010 Spring

### 2010 Spring Math Colloquia

February 10
Anna Mummert (Marshall)
Parameter sensitivity analysis for mathematical modeling

April 14
Suman Sanyal (Marshall)
Stochastic dynamic equations and their applications

April 21
John Drost (Marshall)
Inheritance, bankruptcy, and the Talmud

2009 Fall

### 2009 Fall Math Colloquia

September 16
Carl Mummert (Marshall)
Gaming around with topology

October 15
Sydney Thembinkosi Mkhatshwa (Marshall)

November 11
Duane Farnsworth (Marshall)
Approximation Numbers and Ideals of Operators

2006 Fall

### 2006 Fall Math Colloquia

October 19
Peter Saveliev (Marshall)
Low level vision through topological glasses

2005 Spring

### 2005 Spring Math Colloquia

February 22
Norah Esty (University of California – Berkeley)
Topological Properties of Orbit Sets for Groups of Homeomorphisms

February 24
Elmas Irmak (Michigan State University)
Mapping Class Groups

March 3
Akhtar Khan (Michigan Technological University)
An inverse problem in elasticity

April 8
Judith Silver
Conics in Projective Geometry

April 22
Bonnie Shook
Topological Approaches to Fingerprint Identification
Nathan Cantrell
Cubical Homology in Medical Imaging

April 29
Arthur Porter (Professor Emeritus, University of Toronto)
Manchester University’s Contributions to Analog and Digital Computing

2004 Fall

### 2004 Fall Math Colloquia

September 24
Alfred Akinsete
The winning probability and ranking models for teams in soccer tournaments

October 8
Ralph Oberste-Vorth
From Chaos to Stability: Dynamic Equations Parameterized by Time Scales PDF

October 22
John L. Drost
What is the opposite of a prime number?

November 5
Elizabeth Duke and Kelli Hall
Time Scale Calculus and Dynamical Systems

November 19
Christopher Johnson and Peter Saveliev
Topological Proteomics: Pure Mathematics in Life Sciences

2004 Spring

### 2004 Spring Math Colloquia

January 23
Yulia Dementieva
Statistical approaches to gene mapping

February 6
Linda Hamilton
Robotics of the Mars Station Program

February 19
Basant Karna (Baylor University)
Eigenvalue Comparison for Multipoint Boundary Value Problems

February 24
John (Matt) Matthews (Duke University)
Granular Materials: An Introduction & Application to Hopper Flows

February 27
Mohamed Elhamdadi (University of South Florida)
On knot invariants

March 5
Scott Sarra
Scattered Data Approximation with Radial Basis Functions

April 2
John L. Drost
Arrow’s Theorem or Why we all just can’t get along

2003 Fall

### 2003 Fall Math Colloquia

September 26
John L. Drost

October 10
Peter Saveliev
From slot machines to topology through calculus

October 24
Kelli Hall
Escher’s Tilings and Ribbons

November 7
Judith Silver
The Spherical Metric Project

December 5
Bonita Lawrence
Time Scales: A Snappy Link between Continuous Processes and Discrete Processes