Student Papers: Schedule

 

Speaker and Title

Time

Room

Brian D. Ginsberg, Yale University

The Nearly Secret Theorem of E. Midy – An Extension after 165   Years

5:00-5:10

270

Elizabeth Bellenot, Wellesley College

 Effects of Biological Invasions on Ecological Communities

5:15-5:25

270

Jessica S. Lee, Wellesley College

 Mersenne Primes

5:30-5:40

270

Michael J. Coleman, Boston University and Sidharth Rupani, WPI

Modeling iBOT Belt Dynamics

5:45-5:55

270

Seila Selimovic, Wellesley College

Who Wins: The Mathematician or The Physicist?  The Dirac Delta function and Its Use in Quantum Mechanics

6:00-6:10

270

 

 

 

Iuli Pascu, Wellesley College

A Graphical Interpretation for Complementary Sequences

5:00-5:10

274

Karin Steece, Wellesley College

The Chinese Postman Problem

5:15-5:25

274

XinXin Du, Wellesley College

Monte Carlo Simulations on One Electron Per Site, Two-Dimensional Square Lattices

5:30-5:40

274

Paula F. Popescu, Wellesley College

Games with Hats

5:45-5:55

274

Kathleen Leahy, College of the Holy Cross

Enigma – The Code that Changed History

6:00-6:10

274

 

Charlie Rossetti and Matthew Angelucci, Bentley College

Dynamica

5:00-5:10

278

Brandon Dwyer, Bentley College

A Student’s Look at the First Actuarial Exam

5:15-5:25

278

Jenny Kirouac, Westfield State College

Naming Really Large Numbers

5:30-5:40

278

Kari Lock, Williams College

Making Best Approximates Appear Through Magical Intervals

5:45-5:55

278

Neil Hoffman, Williams College

Double Bubbles in Other Universes

6:00-6:10

278

 

Speaker and Title

Time

Room

Kathleen Smith, Norwich University

Vertex Total Magic Labelings

5:00-5:10

392

Jerzy Wieczorek, Olin College

Solving ‘Rubik’s Polyhedra’ Using Three-Cycles,

5:15-5:25

392

Joelle Arnold, Olin College

The Assignment Problem and Optimizing Registration

5:30-5:40

392

Janet Tsai, Olin College

You Can Make Anything with One Straight Cut

5:45-5:55

392

Ben Kraines and Siddartha Rao, Middlebury College

Extreme Points and Lipschitz Conditions for Functions in a Certain Zygmund Class

6:00-6:10

392

 

 

 

Matthew Stephen Palmacci, Framingham State College

The Golden Ratio

5:00-5:10

396

Alison Fish, Merrimack College

The Golden Ratio and Three-Dimensional Geometry

5:15-5:25

396

Kaitlyn ONeil, Merrimack College

Pretzel Knots and Colorability

5:30-5:40

396

Kevin Roberge, University of Maine

Algebraic Topology and Elementary Circuits

5:45-5:55

396

Michael A. Burr, Tufts University

Simplicial Depth: An Improved Definition, Analysis, and Efficiency for the Finite Sample Case

6:00-6:10

396


Student Papers: Abstracts

 

Matthew Angelucci, Bentley College                                                                     5:00-5:10, room 278

Dynamica                    

            In this talk we present Dynamica, a software package running under Mathematica that helps researchers gain insight into the behavior of dynamical systems. The various features of the software are demonstrated on a biological model of Lyme disease described by a difference equation.

 

Joelle Arnold, Olin College                                                                                    5:30-5:40, room 392

The Assignment Problem and Optimizing Registration

Consider the arranged marriages of a fixed and finite number of heterosexual couples. Suppose that each woman gets to make a list of her preferred husbands, but that the men have no say. We will discuss the conditions under which each woman can be paired with a suitable husband - this is Hall’s marriage problem. The Assignment Problem is any scenario in which a group of people or other entities are to be matched to another group of people or entities, and in which both groups have the same number of members. By either one group or both groups ranking preferences, an optimization can be found. We arrange the data in a matrix and by using the Hungarian Method, may make the best matches. This procedure is used to solve job training, hypothetical marriage and shipping route problems. We will investigate using these two methods to optimize the registration process here at Olin. In this manner, we should be able to maximize student satisfaction with spring schedules.

 

Elizabeth Bellenot, Wellesley College                                                                    5:15-5:25, room 270

Effects of Biological Invasions on Ecological Communities                                                                      

In an ecological community with n distinct species, what happens when an invader species is introduced?  By studying food webs using matrix analysis and simple graph theory, we examine cases where we can predict which resident species will increase, decrease, or has no change in population. We also look at cases where the outcome is ambiguous.

 

Michael A. Burr, Tufts University                                                                          6:00-6:10, room 396

Simplicial Depth: An Improved Definition, Analysis, and Efficiency for the Finite Sample Case

As proposed by Liu (1990) the simplicial depth of a point  with respect to a probability distribution  on  is the probability that  belongs to a random simplex in . The simplicial depth of  with respect to a data set  in  is the fraction of the closed simplices given by  of the data points containing the point . We propose an alternative definition for simplicial depth which continues to remain valid over a continuous probability field, but also fixes some of the problems for the finite sample case, including those discussed by Zuo and Serfling (2000). Additionally, we discuss the effect of the revised definition on the efficiency of previously developed algorithms and prove tight bounds on the value of the simplicial depth based on the half-space depth.

 

Michael J. Coleman, Boston University                                                                 5:45-5:55, room 270

Modeling iBOT Belt Dynamics

The iBOT, a revolutionary personal mobility device developed by DEKA Research and Development Corporation, contains several belts that transfer mechanical power through the system. The dynamic characteristics of the belts are obviously important to the operation of the iBOT. Our task is to create a mathematical model of some aspects of the belt dynamics. Partial and ordinary differential equations and Lagrangian dynamics are employed to understand the elements of this electro-mechanical system.  Ultimately, finite difference numerical methods are applied to solve the rather complicated system of governing equations developed. The results from our mathematical model are compared with those from actual experiments.

 

XinXin Du, Wellesley College                                                                                 5:30-5:40, room 274

Monte Carlo Simulations on One Electron Per Site, Two-Dimensional Square Lattices

I used Monte Carlo methods to do random walks through configuration space on two-dimensional, square lattices, computing the energy and the magnetism of the system, and finding the ground state of the system.  Using the Metropolis algorithm, I simulated a situation where the system sits at a particular temperature and looked at its thermodynamic behavior.  The Metropolis algorithm also allowed me to overcome the problem of arriving at metastable states instead of the ground state in some cases.

 

Brandon Dwyer, Bentley College                                                                            5:15-5:25, room 278

A Student’s Look at the First Actuarial Exam

If a student is looking seriously into a career as an actuary, they should begin the exam process while still in college.  The Course I exam contains problems relating to calculus and probability (both discrete and continuous).  This presentation will look at how to prepare for the exam including strategies for studying.  Two typical exam questions will also be presented.

 

Alison Fish, Merrimack College                                                                             5:15-5:25, room 396

The Golden Ratio and Three-Dimensional Geometry

The golden ratio, represented by j (phi) is found in many areas of mathematics. This talk will discuss the golden ratio and how it can be found in three-dimensional geometric shapes such as polyhedra.  Golden rectangles, which exhibit this ratio, exist within the polyhedra. Also the coordinates of the vertices of the polyhedra and the relationship of the edges include the golden ratio.

 

Brian D. Ginsberg, Yale University                                                                        5:00-5:10, room 270

The Nearly Secret Theorem of E. Midy – An Extension after 165 Years

This work extends Midy’s theorem — a curious, old number theory result about parts of decimals of even period—to a wider class of fractions whose period need not be even. Avenues for further extension are also explored.

 

Neil Hoffman, Williams College                                                                              6:00-6:10, room 278

Double Bubbles in Other Universes

The recently proved Double Bubble Conjecture says that the familiar double soap bubble is the least-area way to enclose and separate two regions of prescribed volumes in . We report on extensions to other three-dimensional universes.

 

Jenny Kirouac, Westfield State College                                                                  5:30-5:40, room 278

Naming Really Large Numbers

You know thousand, and million, and billion, and trillion. Ten thousand, ten million, ten billion, and ten trillion, but do you recall the numbers that come after them all? Shouldn`t we have names for bigger and bigger numbers? And what exactly is a zillion? This talk will delve into a system of naming numbers that not only exceeds our traditional system, but also allows us to keep naming larger and larger numbers without limit. Of course, we will also mention some of the famous numbers and say how they can be alternatively named in this new system: large numbers like the perplexing Googolplex number, the merciful Mersenne primes, and the invigorating Vinogradov`s number. After experiencing this talk you will know lots of amazingly large numbers AND you will be able to name any number you come across.


Ben Kraines, Middlebury College                                                                          6:00-6:10, room 392

Extreme Points and Lipschitz Conditions for Functions in a Certain Zygmund Class

The Tagaki–van der Waerden function is an important example of a continuous nowhere–differentiable function.  Although it is nowhere differentiable, it is possible to define an analogue to the derivative via the “dyadic difference quotient” sequence. This paper concerns functions whose dyadic difference quotients have modulus one.  We use the dyadic difference quotient to investigate Lipschitz points and extreme points for such functions in a way that parallels the use of the derivative in studying extreme points and Lipschitz behavior in real variable calculus.

 

Kathleen Leahy, College of the Holy Cross                                                           6:00-6:10, room 274

Enigma – The Code that Changed History

In this talk we will give a brief history of the Enigma code used by the Germans in World War II. We will describe the machine used to encode and decode as well as some of the mathematics involved. We will also discuss the connection between the breaking of the Enigma code and the creation of the first digital computer. 

 

Jessica S. Lee, Wellesley College                                                                           5:30-5:40, room 270

Mersenne Primes

As early as 300 B.C., Euclid studied prime numbers, which are numbers divisible only by one and themselves.  Until 1536, mathematicians believed that all numbers of the form  were prime for all primes .  While this conjecture is false, many people now have joined the search for primes of that form, now dubbed Mersenne Primes after the Frenchman who studied them at great length.  This talk briefly outlines the history of these rare primes, the current on-going search for them, as well as providing an introduction to some of the unsolved mysteries surrounding Mersennes.

 

Kari Lock, Williams College                                                                                   5:45-5:55, room 278

Making Best Approximates Appear Through Magical Intervals

Let  be a real, irrational number. Given a positive integer q, an important question in diophantine approximation is: how do we determine exactly when q is the denominator of a “best rational approximate” to ? Using the theory of continued fractions and their convergents, I show that if the continued fraction expansion of  has the form , then a positive integer q is a denominator of a best approximate to  if and only if the interval

 

contains an integer. This result extends the work of several mathematicians who proved analogous theorems for the Golden Ratio (that is, for ) and the generalized Golden Ratio (that is, for).

 

Kaitlyn ONeil, Merrimack College                                                                         5:30-5:40, room 396

Pretzel Knots and Colorability

My colleagues and I develop a formula for determining the number of fundamentally different ways that an -colorable knot can be -colored, based on the -nullity of the knot.  We then determine the m-nullity of any  pretzel knot, and thus a way to determine the -colorability and number of fundamentally different -colorings of any pretzel knot.


 

Matthew Stephen Palmacci, Framingham State College                                        5:00-5:10, room 396

The Golden Ratio

A proportion that can be seen throughout nature and man-made structures is the Golden Ratio, often denoted by the Greek letter phi.  In nature, the divine section can be acquired from measurements of the human body, plants and Uranium.  Man-made structures can also be used to appreciate this wonderful proportion.  Phi can be found in the building of musical instruments, the Fibonacci sequence, ancient pyramids, and even electrical networks.  The divine proportion reveals an interesting and beautiful pattern that emerges from the wonders of nature.

 

Iuli Pascu, Wellesley College                                                                                  5:00-5:10, room 274

A Graphical Interpretation for Complementary Sequences

Two sequences with the property that each natural number is contained in exactly one of them are called complementary sequences. I will present a graphical way to generate complementary sequences. Starting from this graphical interpretation, I will show how to derive some interesting properties of these sequences.

 

Paula F. Popescu, Wellesley College                                                                      5:45-5:55, room 274

Games with Hats

In his article "Games People Don't Play", Peter Winkler describes two different games in which colored hats get distributed randomly to a team of players. Each player has to guess the color of his own hat, based on observation of his teammates' hats and a team strategy designed in advance. In both of the games, only two hat colors are allowed. In this talk, we will discuss strategies for analogous games with multiple hat colors.

 

Siddartha Rao, Middlebury College                                                                        6:00-6:10, room 392

Extreme Points and Lipschitz Conditions for Functions in a Certain Zygmund Class

(See Ben Kraines for abstract.)

 

Kevin Roberge, University of Maine                                                                     5:45-5:55, room 396

Algebraic Topology and Elementary Circuits

What does a torus or a Möbius band have to do with electrical circuits?  How does the presence of “holes” in a topological space affect the existence of solutions for currents and voltages?  These questions are the sorts that drive the subject matter of this presentation which presents some connections between algebraic topology and circuit analysis.  This talk will present the basic idea of algebraic topology and how we might use it to talk about circuits.  Elementary circuits will be presented and the application of algebraic topology to these circuits will be outlined.

 

Charlie Rossetti, Bentley College                                                                            5:00-5:10, room 278

Dynamica                    

(See Matthew Angelucci for abstract.)

 

Sidharth Rupani, Worcester Polytechnic Institute                                                   5:45-5:55, room 270

Modeling iBOT Belt Dynamics

(See Michael J. Coleman for abstract.)

 

Seila Selimovic, Wellesley College                                                                          6:00-6:10, room 270

Who Wins: The Mathematician or The Physicist?  The Dirac Delta function and Its Use in

Quantum Mechanics

Mathematical expressions are often presented to undergraduate Physics students without full explanations. In this study, we choose to examine one such object, the Dirac distribution, in detail. The application of this distribution in quantum mechanics shows one of the common mathematical mistakes in physics. Physicists often treat the Dirac “delta-function” as a function instead of as a distribution that is the limit to approximations of the function  at a given . This distinction is important for mathematicians, but for physicists it does not carry much weight. In this work we establish differences between functions and distributions, demonstrate why delta functions do not exist, and explain in which mathematical framework and physical problems one can use incorrect terminology and thus speak about delta-functions.

 

Kathleen Smith, Norwich University                                                                      5:00-5:10, room 392

Vertex Total Magic Labelings

A total labeling of a graph is an assignment of consecutive integers 1,2, …, to the vertices and edges of the graph.  The weight of each vertex is the sum of its label and the labels of its incident edges.  A vertex magic total labeling is a total labeling in which the weight of each vertex is constant.  We will focus on the odd complete graphs.  Previously, magic squares had been used to construct labelings with only a few different magic constants.  In this talk, we will introduce a new technique that is used to construct labelings for all possible magic constants.  This solves an important conjecture for odd complete graphs.

 

Karin Steece, Wellesley College                                                                             5:15-5:25, room 274

The Chinese Postman Problem

Originally studied by the Chinese mathematician M. Kwan, the Chinese Postman Problem involves finding the shortest distance a mail carrier can travel in order to deliver the mail to all the houses on his route, and then return to the post office. For an Eulerian graph, the problem reduces to finding an Eulerian circuit. However, it turns out that a good algorithm exists even in the non-Eulerian case. I will discuss the basics of the solution and present a few additional examples of how the algorithm can be applied in the real world.

 

Janet Tsai, Olin College                                                                                         5:45-5:55, room 392

You Can Make Anything with One Straight Cut

According to legend, Betsy Ross was given the responsibility of creating the first American flag in 1776 after she impressed General George Washington with an interesting way to create a five-pointed star. By simply folding a piece of cloth and making one snip with her scissors, Betsy made a regular five-pointed star which is now famous, appearing 50 times on every American flag. But Betsy’s cut leads to a larger question: is it possible to create any 2-D polygon by folding a piece of paper and making one straight cut? This question has been studied extensively during the past ten years, resulting in two distinct proofs which demonstrate how any polygonal shape can be created by cutting once in a straight line. Our discussion will begin with the activity of creating a five-pointed star as Betsy Ross did to introduce the idea of folding, cutting, and unfolding to yield a shape. From there, we will present a brief introduction to the problem and then move to a more in depth look at the disc-packing method of proof. Relevant connections will be made to the fields of graph theory, combinatorics, and origami mathematics.

 

Jerzy Wieczorek, Olin College                                                                               5:15-5:25, room 392

Solving ‘Rubik’s Polyhedra’ Using Three-Cycles

The Rubik’s Cube is only the most prominent member of a family of related puzzles consisting of colored regular polyhedra with rotating faces. This paper uses group theory to describe a set of simple solution algorithms that can be constructed for any such puzzle. We show that it is possible to create sequences of face rotations that result in a motion of exactly three pieces on a polyhedron puzzle, leaving all other pieces as before; and that the smallest possible such motion is of three pieces, i.e., that it is impossible to have exactly two pieces out of place. Thus, we can always solve these puzzles using nothing more than the easily constructed three-cycles.


New Colleague Presentations

 

Session 1, Room 270

8:00 am             Complementary Sequences                                                                                                

                        Sam Vandervelde, Wellesley College

We present an elegant method for constructing a partition of the positive integers into a set of sequences, beginning with the Fibonacci and Lucas numbers.

 

8:20 am             Landscape Erosion

                        Ted Welsh, Westfield State College

How do you describe landscape erosion?  We will look at a system of partial differential equations: What problems arise?  How can we fix these problems?

 

8:40 am             Technology in Mathematics for Preservice Elementary Teachers

                        Barbara Boschmans, Plymouth State College

A study was conducted last fall on the self efficacy of preservice elementary teachers and using technology in mathematics.  Projects were developed and data was collected from experimental and control groups.  This presentation will discuss the projects, the study, and the results.

 

Session 2, Room 274

8:00 am             Error-control codes and related areas of discrete mathematics  

                        Sarah Spence, Franklin W. Olin College of Engineering,

Error-control codes are an important aspect of algebraic coding theory. For example, CDs use error-control codes so that a CD player can read data even if they have been corrupted by imperfections on the CD.  This talk will present some undergraduate-accessible basics of algebraic coding theory as well as related teaching interests and projects.

 

8:20 am             A Historic Point of View on Trigonometric Functions

                        Semra Kilic-Bahi, Colby Sawyer College,

The presentation will first focus on different techniques applied by ancient civilizations to measure the earth. Then the effect of some approaches on the development of trigonometric functions will be emphasized.

 

8:40 am             The Regularity of Weakly Harmonic Maps on Riemannian Manifolds with Bounded Measurable Metrics

                        Wataru Ishizuka, Providence College.

The Hölder continuity of weakly harmonic maps on Riemannian manifolds with non-smooth metrics will be discussed.

 

Session 3, Room 278

8:00 am             Rolle’s Theorem over Finite and Local Fields

                        Cristina Ballantine, College of the Holy Cross,

Rolle’s Theorem implies that if a polynomial splits over the reals, its derivative does as well. We investigate this property over finite and local fields.

 

8:20 am             An Examination of Teacher Knowledge Base Among Undergraduate Mathematics Faculty

                        Kimberly B. Santucci, University of Connecticut

This research examined the knowledge base for teaching and instructional practice of seven undergraduate mathematics faculty teaching calculus. Themes across cases and a teacher knowledge base framework will be presented.

 

8:40 am             An Introduction to Weak 2-cocycles

                        Jill Shahverdian, Quinnipiac University

I will introduce the theory of weak 2-cocycles as a generalization of the theory of Galois 2-cocycles.


Contributed Papers

 

Session 1, Room 270

3:30-3:45           Euler Goes Beyond Isosceles                                                                                      

                        Ed Sandifer, Western Connecticut State University

We all know what happens if a triangle has two equal angles, say A and B. Such triangles are isosceles, and there is a simple relation on their sides, a = b.  But what if one angle is an integer multiple of another angle, say B = 2A, or B = 3 A?

 

3:45 – 4:00        Mathematical Models and Art in the Early 20th Century

                        Angela Vierling, Boston University

For thousands of years, artists, as well as mathematicians, have been interested in solid geometric forms. The drawing and painting of polyhedral models can be simply a teaching tool, but, for others, these forms have represented perfection and truth itself. In the nineteenth century, mathematicians began to produce less regular and more startling solid figures. The strange beauty of these forms had an effect on many artists, particularly those associated with the constructivist and surrealist movements.

 

4:00 – 4:15        A Mathematician at a K-8 School

                        Debbie Borkovitz, Wheelock College

Last year I spent a portion of my sabbatical at the Young Achievers Science and Math School in Boston, where I worked primarily with Wheelock College graduate students, but also with children, teachers, and administrators at the school.  In the talk, I will share some of the children’s work, some anecdotes about working with the new teachers, and a few thoughts on how the school experience affected my work in preparing future elementary teachers in mathematics.

 

4:15 – 4:30        Group Quizzes using the Think-Share-Write Method

                        Hema Gopalakrishnan, Sacred Heart University

Group Quizzes using the Think-Share-Write strategy can be effective in engaging students and enhancing their learning in the classroom. In this talk, I describe my experiences with implementing this method in lower division and upper division mathematics courses. 

 

Session 2, Room 274

3:30 – 3:45      The Formulation of Vector Analysis Valid in All Coordinate Systems

                        Domina Eberle Spencer and Terri L. Mascardo, University of Connecticut

The paper presents a formulation of vector analysis valid in all coordinate systems. The pedagogical value of this formulation is easily seen when compared to the established formulation, which is valid only in rectangular coordinates and is being taught in elementary calculus classes. Historical development is traced back to Hamilton, Grassmann, Heaviside and Gibbs and the implications of their efforts when considering extending vector analysis to curvilinear coordinates and non-uniform fields. Proper definitions are given for the unit vectors, the gradient and the divergence and curl.

 

3:45 – 4:00        Using a Partial Singular Value Decomposition to Approximate a Large Sparse Rectangular Matrix

                        James Baglama, University of Rhode Island

One of the most useful tools in linear algebra is the Singular Value Decomposition (SVD) of a large sparse matrix. There are numerous applications that use SVD e.g., information retrieval, two-dimensional image compression, and digital signal processing. Many SVD applications generate large rectangular matrices, but only require a few singular values to produce an acceptable answer. Recently, we have developed a method, the augmented Lanczos bidiagonalization method along with a MATLAB code for computing a few singular values and vectors. This talk is suitable for those who have had some background in linear algebra. Topics for this talk will include the mathematics behind SVD, a brief discussion of the Lanczos bidiagonalization method, and some applications