Proposals

Below are some proposals for talks from the past (and current). By clicking on the ID number, more details are shown. By default, these are sorted chronologically (recent first) and by then by last name. The data can be sorted by alternate means by using the links at the top right, each allowing ascending or descending orders.

Displaying 141-160 of 471 results.
ID: 440
Year: 2016
Name: Henry Walker
Institution: Grinnell College
Subject area(s): Pedagogy, collaborative learning, student engagement
Title of Talk: A Lab-based Pedagoy that Emphasizes Collaboration

Abstract: Following pedagogy pioneered by mathematician Eugene Herman at Grinnell College, this talk describes my experiences with a lab-based pedagogy in which students work collaboratively in pairs for each class session. As an instructor, I lecture about 4 hours per month, usually in 5-10 minute mini-lectures. Elements of this approach have been studied extensively by others to show effectiveness. Further, my own experience shows I can cover about 20% more material with this pedagogy over a traditional format, and test scores are better. Since this talk will focus upon pedagogy, the talk will largely be content-free.
ID: 441
Year: 2016
Name: Henry Walker
Institution: Grinnell College
Subject area(s): Course Syllabi and Online Materials
Title of Talk: Using a Database to Support a Course Home Page, Syllabus, Schedule, and Other Online Materials

Abstract: With static Web pages for a course, posting of daily readings, assignments, etc. requires either constant editing of pages or a search for materials relevant for each given day. Further, adjustments in time allocated for one topic likely requires manual changes in several days that follow. As a result, modifications in a course to accomodate student needs are labor intensive and consistency of schedules can be troublesome. Use of a database behind the scenes resolves many of these maintenance challenges. A student going to a course home page can view the assignments for the previous day, current day, and next day, together with a statement of the next course deadlines. Links to readings and assignments can be dynamic — automatically updated daily. Adjustments to course schedules can be made with the click of just a few buttons. Part of the talk will include a demonstration of a sample dynamic format for a current course. (Development of this type of course interface might make an interesting assignment for one or more computing students!)
ID: 186
Year: 2007
Name: David Romano
Institution: Grinnell College
Subject area(s): Convex geometry
Title of Talk: Connected goalies for convex polygons

Abstract: Given a compact convex body K in the plane, call a connected 1-dimensional set G in the plane a goalie if it intersects all the straight lines that intersect K. This talk is concerned with the problem of finding the minimal length goalie for polygons. For any polygon P with n sides, we prove that any shortest goalie G for P has convex hull CH(G) a polygon with at most 2n sides. For triangles T, the minimal length goalie is the Steiner minimal tree for T. This is no longer true in the case of quadrilaterals, in which case a Steiner minimal tree need not be a minimal goalie.
ID: 190
Year: 2007
Name: Marc Chamberland
Institution: Grinnell College
Subject area(s): sequences, number theory, dynamics, fractals
Title of Talk: The Mean-Median Map

Abstract: Starting with a non-empty finite set S_n={x_1,\ldots,x_n} contained in R, generate the unique number x_{n+1} which satisfies the mean-median equation (x_1 + \cdots + x_n + x_{n+1}/(n+1) = median(S_n) . As usual, we define the median of the set S_n = {x_1,\ldots,x_n}, where x_1<= ... <= x_n, as median (S_n) = \left\{ x_{(n+1)/2}, n odd , \frac{x_{n/2} + x_{n/2+1}}{2}, n even . By applying the mean-median equation repeatedly to a set one generates an infinite sequence {x_k}_{k=1}^\infty. The dynamics of this map are surprising! Most maps tend to have either relatively simple dynamics or chaotic dynamics. While the mean-median map seems to be asymptotically constant, it seems very hard to predict. This talk will showcase the work done to date. This is joint work with Mario Martelli (Claremont McKenna College).
ID: 450
Year: 2016
Name: Marc Chamberland
Institution: Grinnell College
Subject area(s):
Title of Talk: When Choice is an Illusion

Abstract: While choice is usually a valued commodity, it sometimes does not make a difference. In this talk, I look at various mathematical phenomena where, regardless of your choice, the final outcome is surprisingly unchanged.
ID: 201
Year: 2007
Name: Henry Walker
Institution: Grinnell College
Subject area(s):
Title of Talk: Ethics and Standards

Abstract: The MAA Committee on the Profession (CotP) has been asked by the MAA Board of Governors to draft a Statement of Ethics Standards. This talk will provide an overview to the work on this project and encourage reactions to the current working draft.
ID: 485
Year: 2017
Name: Jong Hoon Bae
Institution: Grinnell College
Subject area(s):
Title of Talk: Cauldron: An IDE for Modular Development of Chemical Reaction Networks

Abstract: Chemical reaction networks (CRNs) are widely used in the physical sciences to model reactions between molecules, and they are closely related to Petri nets and population protocols. Although the CRN model is equivalent in power to modern programming languages, it does not naturally support important software engineering principles such as abstraction and reuse. As a result, CRNs are challenging to debug, verify, extend, reuse, and maintain. In this talk we introduce Cauldron, an integrated development environment (IDE) for modular CRN development. Cauldron supports three new CRN design methods introduced by Klinge, Lathrop, and Lutz in 2016: (1) Input/output CRNs, (2) closed-sub CRNS, and (3) extension operators. I/O CRNs extend the CRN model to allow receiving external input signals. A closed sub-CRN encapsulates a behavior within an existing CRN in a way that is self-contained. Extension operators are used to automatically add functionality to a CRN without affecting its original behavior. By making these methods practical to developers, Cauldron naturally supports modular CRN design. For example, users can divide a CRN into independent sub-CRNs, test them separately, and reuse them in other CRNs. Furthermore, users can mark species as inputs and specify them with common elementary functions, by drawing a function, or by connecting them to another CRN. Many commonly used CRNs and extension operators are also included as libraries in Cauldron.
ID: 486
Year: 2017
Name: Jong Hoon Bae
Institution: Grinnell College
Subject area(s):
Title of Talk: Cauldron: An IDE for Modular Development of Chemical Reaction Networks

Abstract: Chemical reaction networks (CRNs) are widely used in the physical sciences to model reactions between molecules, and they are closely related to Petri nets and population protocols. Although the CRN model is equivalent in power to modern programming languages, it does not naturally support important software engineering principles such as abstraction and reuse. As a result, CRNs are challenging to debug, verify, extend, reuse, and maintain. In this talk we introduce Cauldron, an integrated development environment (IDE) for modular CRN development. Cauldron supports three new CRN design methods introduced by Klinge, Lathrop, and Lutz in 2016: (1) Input/output CRNs, (2) closed-sub CRNS, and (3) extension operators. I/O CRNs extend the CRN model to allow receiving external input signals. A closed sub-CRN encapsulates a behavior within an existing CRN in a way that is self-contained. Extension operators are used to automatically add functionality to a CRN without affecting its original behavior. By making these methods practical to developers, Cauldron naturally supports modular CRN design. For example, users can divide a CRN into independent sub-CRNs, test them separately, and reuse them in other CRNs. Furthermore, users can mark species as inputs and specify them with common elementary functions, by drawing a function, or by connecting them to another CRN. Many commonly used CRNs and extension operators are also included as libraries in Cauldron.
ID: 431
Year: 2015
Name: Francis Su
Institution: Harvey Mudd College
Subject area(s):
Title of Talk: Voting in Agreeable Societies

Abstract: When does a majority exist in a voting situation? How does the geometry of the political spectrum influence the outcome? What does mathematics have to say about how people behave? When mathematical objects have a social interpretation, the associated results have social applications. We will show how math can be used to model people's preferences and understand voting in "agreeable" societies. This talk also features research with undergraduates.
ID: 455
Year: 2016
Name: Art Benjamin
Institution: Harvey Mudd College
Subject area(s):
Title of Talk: Mathemagics!

Abstract: Arthur Benjamin will demonstrate and explain how to mentally add and multiply numbers faster than a calculator, how to figure out the day of the week of any date in history, and other amazing feats of mind. He has presented his mixture of math and magic to audiences all over the world.
ID: 576
Year: 2022
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Institution: hZfHkLnweN
Subject area(s): uqJKXIEllzYMVERy
Title of Talk: fnZOTELxLsKibpvdNLR

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ID: 558
Year: 2021
Name: mpazkvt ubUxGrQpZHbbYZv
Institution: icImzteiWthAdt
Subject area(s): QZAaMIFgkRreqn
Title of Talk: iNgEWUcEePPq

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ID: 364
Year: 2013
Name: Charles Ashbacher
Institution: Independent
Subject area(s):
Title of Talk: Are Drug Tests As a Precondition for Welfare Receipt Cost-Effective?

Abstract: Recently some states have implemented a program where an applicant for welfare must take and pass a drug test in order to receive benefits. Using the current law regarding how testing can be performed and some fact-based assumptions, a model for how cost-effective this program is can be developed. This model has been used as an exercise in a management science class as it can be applied to both public and corporate policies.
ID: 247
Year: 2008
Name: Carl Cowen
Institution: Indiana University--Purdue University Indianapolis
Subject area(s):
Title of Talk: Connections Between Mathematics and Biology

Abstract: Dr. Rita Colwell, a research microbiologist and former Director of the National Science Foundation, regards the mathematical sciences as the backbone for US Scientific and Engineering research. Many scholars see the next few decades as a time of intensive progress in the biological sciences. Dr. Colwell sees mathematics as being an integral part of the progress in biology, not a traditional view, but a forward looking one. In this talk, Carl Cowen will outline some of the research areas in the emerging collaborations between mathematical and biological scientists. In addition, Cowen, who began his study of the mathematics of neuroscience in 2002-03 at the Mathematical Biosciences Institute at Ohio State University, and who worked in 2003-04 as a junior post-doc in the lab of Prof. Christie Sahley in the Purdue University Biology Department, will illustrate the connection between mathematics and neuroscience with a discussion of the Pulfrich phenomenon, an experiment that helps illuminate how the brain processes visual images. There are few mathematical or biological prerequisites for this discussion.
ID: 248
Year: 2008
Name: Carl Cowen
Institution: Indiana University--Purdue University Indianapolis
Subject area(s):
Title of Talk: Rearranging the Alternating Harmonic Series

Abstract: The commutative property of addition is so familiar to all of us as school children that it comes as a shock to those studying college level mathematics that NOT all 'natural extensions' of the law are true! One of the first instances that we see the failure of an extended commutative law of addition is in infinite series. Often in the introduction to infinite series in calculus, one sees Riemann's Theorem: A conditionally convergent series can be rearranged to sum to any number. Unfortunately, the usual proof of this theorem does not indicate what the sum of a given rearrangement is. In this talk, we will examine the best known conditionally convergent series, the alternating harmonic series, and show how to find the sum of any rearrangement in which the positive terms and the negative terms are each in their usual order.
ID: 256
Year: 2009
Name: Donald Peterson
Institution: Iowa State University
Subject area(s): Encryption, Number Theory
Title of Talk: The 1/P Pseudo-Random Number Generator

Abstract: Seemingly suitable for encryption, the 1/P pseudo-random number generator quickly outputs a long, well-distributed sequence of digits from a small seed. However, without any prior knowledge of the seed, it can be determined and the sequence can be predicted both forwards and backwards by careful examination of 2|P| + 1 digits of the sequence. This article examines how to develop the generator, and more importantly given a small bit of any sequence, how to predict the remaining sequence.
ID: 257
Year: 2009
Name: Michael Hilgemann
Institution: Iowa State University
Subject area(s): Algebra
Title of Talk: The classification of finite-dimensional Hopf algebras

Abstract: Hopf algebras can be considered generalizations of groups, and group algebras are basic examples of such objects. In recent years there have been developments in the classification of finite-dimensional Hopf algebras over an algebraically closed field of characteristic 0, which include many examples which are neither group algebras nor the linear dual of group algebras. In this talk, we will highlight these classification results and some of the useful properties that general finite-dimensional Hopf algebras share with finite group algebras. In particular, we will discuss recent joint work with Richard Ng that completes the classification of Hopf algebras of dimension 2p^2, for p an odd prime.
ID: 259
Year: 2009
Name: Christian Roettger
Institution: Iowa State University
Subject area(s): Algebra, elementary number theory
Title of Talk: Sequences and their annihilators

Abstract: Annihilating polynomials have been widely used in geometry and to study sequences over fields and over the integers Z. We use the same simple ideas to study sequences over Z modulo n. There are surprising difficulties, surprisingly nice results and an open conjecture. We can demonstrate some applications to recurrence sequences like the Fibonacci and Lucas numbers, or discrete dynamical systems. Joint work with John Gillespie. Prerequisites: ring, ideal, quotient ring, Chinese Remainder theorem - suitable for undergraduates with a first course in algebra.
ID: 270
Year: 2009
Name: YiLin Cheng
Institution: Iowa State University
Subject area(s):
Title of Talk: Classification of Hopf algebras 4p-dimension

Abstract: In recent years, there have been much development on the classification of finite dimensional Hopf algebras over a field of characteristic 0. The 4p-dimensional Hopf algebras when p=3 was classified 10 years ago and there are very few results for classification of nonsemisimple Hopf algebras with the dimension which is a mutiple of 4 during this period. In this talk, I will discuss some progress joint work with Richard Ng about 4p-dimensional nonsemisimple Hopf algebras when the odd prime p is less than or equal to 11.
ID: 526
Year: 2019
Name: O'Neill Kingston
Institution: Iowa State University
Subject area(s): Representation theory
Title of Talk: Jeux de taquin

Abstract: Or, in English, the 15 puzzle(s). From integer partitions to algebraic structures, in this talk we explore a classic combinatorial technique and a few of its applications.