## Spring 2019

**Tuesday, January 22nd**

Tom Edgar, '02, Associate Professor of Mathematics, Pacific Lutheran University

"No Numeration Without Representation"

A complicated version of "eeny, meeny, miny, moe," some two-player token collecting games, a mystery of identifying a counterfeit coin, and certain magic card tricks can all be explained by letting go of our usual method of representing the numbers involved. After describing each of the problems, we'll pursue a "choose-your-own-adventure" path to showing how nonstandard numeration systems give rise to interesting solutions to the problems.

Noon

Tome 115

Lunch provided

**Monday, February 11th**

Marc Renault - Professor of Mathematics, Shippensburg University

"Everything you Wanted to Know About the Fibonacci Sequence"

(and some things you didn’t want to know)

In 1994 he learned about the Fibonacci sequence in a number theory class, and has been fascinated by it ever since. This simple sequence of integers 1, 1, 2, 3, 5, 8, 12, 21, 34, 89, ... contains a multitude of patterns that have fascinated mathematicians for centuries. In this talk he’ll introduce the sequence, show some clever proofs for well-known identities, and talk about some recent work concerning the sequence.

3:30pm

Tome 115

Snacks provided

**Friday, March 1st**

Andrew Marchese - Data Scientist at Plated

"Exploring Data Science Case Studies: An Industry Perspective"

The term Data Science has become ubiquitous and almost every tech company strives to hire a data team. But what sort of problems do these teams solve? In this talk, we will go through several different machine learning models, discuss how they work from a technical point of view, and then explore (and code) a real world case study where these models find use in the context of industry.

3:30pm

Tome 115

Snacks provided

**Tuesday, March 19th**

Computer Science Course Information Session

There are a number of changes to the Computer Science major and to the course offerings beginning Fall 2019. Please attend this information session to learn more about the changes, how they will affect you, and which course you should register for next semester.

4:30pm

Tome 115

**Tuesday, March 19th**

Mathematics Drop-In Advising Session

Mathematics faculty members and a representative from the Center for Advising, Internships & Lifelong Career Development will be at tables ready to answer your questions about courses, the major and minor, placement, careers, internships, graduate school, research, study abroad, and so on.

4:00pm

Rector Atrium

Refreshments provided

**Tuesday, April 2nd**

Becky Coutts '03, Director for Instructional Design and PD Resource Development for Computer Science at the College Board

"Beyond the classroom: How Dickinson prepared me for a not-so-traditional career in education"

Becky has had a 15-year career in education, both in and out of the classroom, despite never earning a teaching degree or certification. Hear about the ways in which Dickinson helped prepare her for this career, as well as the work currently being done at the College Board to increase diversity in computer science throughout the country. In addition to her own career path, Becky will discuss other careers in education that exist outside the classroom.

3:30pm

Tome 115

Refreshments provided

**Monday, April 8th**

Uniform Convergence - A One-Woman Play

Written and performed by Corrine Yap

Through the lives of a 19th century Russian mathematician and a present-day Asian-American math professor, this solo piece explores the struggles of two women trying to find their place in a white-male-dominated academic world. Using text, mathematics, movement, and music, the play is an attempt to understand identity and how we communicate who we are.

7:00pm

Althouse 106

**Tuesday, April 9th**

Corrine Yap, Rutgers University

"The Mathematics of Flat-Folding Origami"

A flat origami model is one that can be pressed in a book without introducing new creases - think of the quintessential paper crane. Given an origami crease pattern, can we determine whether or not it will fold flat? Along the way to answering this, we will solve some combinatorial questions using origami, and some origami questions using combinatorics; no prior knowledge of either topic will be assumed. Paper will be provided.

Noon

Tome 115

Lunch provided

**Monday, April 15th**

John Jones '11

"Leveraging Liberal Arts in Your Tech Career"

With constant news of tech companies facilitating the spread of misinformation and automation threatening our future workforce, there's growing backlash around technology that does more harm than good. John Jones (’11) works to find ways technology can do good in the world. He credits Dickinson's liberal arts approach combined with his computer science education for bestowing him with a unique perspective and a broader understanding of how the tools and technologies we all use today shape and impact society. John will talk about his current work at the Case Foundation which includes understanding open source software's role in the philanthropic sector, his career path, and how Dickinson prepared him.

3:30pm

Tome 115

Snacks provided

**Thursday, April 18th**

Mathematics & Computer Science Majors Dinner

Professor David Sulon will present "Periodic Traveling Interfacial Hydroelastic Waves"

Hydroelasticity (and fluid-structure interaction ingeneral) is of considerable interest across many fields, including engineering and biology. We study a mathematical model of hydroelastic waves, which (for example) occur in ice sheets over the ocean, flapping flags, and biological structures. The problem regards two fluids separated by an elastic sheet; the dynamics of this system are also subject to surface tension and gravity. We prove the existence of periodic traveling wave (i.e. periodic waves that move at a constant speed without change in shape) solutions to this system. The choice of technique depends on the dimension (and other properties) of the null space of the equations’ linearization. We present a broad overview of these methods, and highlight how different cases of such a problem in applied mathematics can invite diverse techniques of approach.

Upsilon Pi Epsilon and Pi Mu Epsilon Honor Society Inductions

Departmental Prizes and Awards

Served meal by Dining Services (you must sign up in Tome 201 by April 11th)

**Tuesday, April 30th**

Moyi Tian '19

Faculty Advisor, Professor Dave RIcheson

"Maypole Braids: An Analysis Using the Annular Braid Group"

We use mathematical braids to analyze maypole dances practiced in European May Day festivals. The study of braids started in the early 20*th* century with the motivation of revealing properties of knots and links. The Artin braid group gives an algebraic tool to analyze the braid actions and the equivalence of braids. Later, a variation of ordinary braids, the annular braids, was introduced with additional rules added. In this research, we give three presentations to describe the annular braid group. We also use the annular braid group as a medium to abstract the braids in maypole dances and therefore apply an algebraic analysis. Finally, we discuss some essential properties embedded in the maypole braids, which are related to the invariants of annular braids - the minimum number of crossings and the minimum number of steps.

Noon

Tome 115

Lunch provided

**Wednesday, May 1st**

Daniel Ngo '19

Faculty Advisor, Professor Grant Braught

"Self-Adaptive Chaotic Mutation Operators in Evolutionary Computation"

Genetic algorithms (GA) are inspired by the natural evolutionary process to find near-optimal solutions to difficult computational problems in reasonable time. Genetic Algorithms mimic the process of natural selection and reproduction through parental selection, crossover and mutation of individuals in a population. Some researchers have become interested in using iterated chaotic maps instead of pseudo-random numbers in evolutionary algorithms. This project aims to investigate the evolution of the chaotic map parameter and the distribution of mutation values as the evolutionary need for exploration and exploitation changes at any given time.

11:30am

Tome 115

Lunch provided

**Thursday, May 2nd**

Mengting Chao '20

Faculty Advisor, Professor Lorelei Koss

"Dynamics of the Taylor Series Approximation of the Dixon Elliptic Functions"

The function is a Taylor series approximation of a Dixon elliptic function at the origin, where each c value corresponds to a different Dixon elliptic function. One thing that makes Tc complicated to study is that we cannot solve algebraically for its fixed and periodic points, which is typically the first step to explore a dynamical system resulting from function iteration. Instead, we use a theorem about negative Schwarzian derivatives to find an upper bound on the number of attracting cycles of Tc. Then we utilize the orbits of critical points to explore the location of attracting fixed and periodic points which form those attracting cycles. We also show the existence of a saddle-node bifurcation and a period-doubling bifurcation for Tc.

Noon

Tome 117

Lunch provided

**Friday, May 3rd**

Adam Cogen '19

Faculty Advisor, Professor Farhan Siddiqui

"Empirical Evaluation of Low-Power Wide Area Networks (LPWANs) for Internet of Things"

The Internet of Things (IoT) is expanding at a rapid pace with various types of “things” acquiring Internet connectivity through wireless technologies. Until recently, IoT connectivity was mostly provided via low-power, short-range technologies such as Bluetooth and Zigbee or high-power, long-range cellular technologies such as LTE. LPWAN is an emerging wireless technology that offers unique characteristics including long-range, low-power consumption, and low- cost. In this research, we explore the feasibility of employing an LPWAN technology called LoRa for building an IoT network. Our empirical evaluation is conducted on a real LPWAN testbed constructed using commercially available hardware components (Arduino boards and shields, Raspberry Pi) and open-source LoRa libraries. The testbed is currently functional on the Dickinson College campus. We investigate the performance of LoRa in terms of network coverage, latency, link reliability, and end-device mobility. We also demonstrate how a LoRa network can be enabled to support end-to-end data encryption and examine the overhead incurred by using 128-bit Advanced Encryption Standard (AES) security keys.

11:30am

Tome 115

Lunch provided

**Wednesday, May 8th**

End of Year Mathematics & Computer Science Majors BBQ

Professors will grill hamburgers, hot dogs and veggie burgers.

Noon

Rector Courtyard (Rain Location: Rector Atrium)

Lunch provided