## Fall 1998

[ 12/7/98 | 11/30/98 | 11/16/98 | 11/9/98 | 11/2/98 | 10/26/98 | 10/19/98 | 10/12/98 | 10/5/98 | 9/28/98 | 9/21/98 | 9/14/98 ]

**12/7/98 - Modeling student interaction to evaluate educational microworlds
**Craig Miller

Department of Mathematics and Computer Science

Dickinson College

I will present my work on evaluating educational microworlds through the construction and testing of a computational model of student interaction and learning. This computational system, constructed with the Soar cognitive architecture, simulates a student interacting with the Electric Field Hockey (EFH) microworld, whose educational objective is to provide physics students with a qualitative understanding of electrical interactions. Informed by interviews and recordings of student interaction, I constructed the computer system so that it effectively interacted with the microworld using the same strategies employed by students. By providing an explicit understanding of student knowledge, behavior and learning, the computer model revealed pedagogical deficiencies with the microworld's game-oriented task. These results suggested alternate tasks for interacting with the microworld that would improve student learning. These tasks were then experimentally tested with students and the post-test results support the conclusions derived from the model.

**11/30/98 - Taking The Fifth
**Thomas Drucker

Everyone knows the quadratic formula (at least most of the time) and there are cubic and quartic formulae as well. It was one of the great accomplishments of early 19th century mathematics to show that there is no similar formula for fifth-degree equations. This talk will look at some of the attempts to find a quintic formula and why they were bound to fail. Next semester the sequel will give you encouragement for not panicking if you have a fifth-degree equation and need the solutions, even if you don't have a formula.

**11/16/98 - Preemptive Non-Clairvoyant Scheduling
**Chris S Coulston

Department of Computer Science and Engineering

The Pennsylvania State University

This talk will focus on the problem of preemptive non-clairvoyant scheduling on a single machine. In this model a scheduler receives a number of jobs at different times without prior knowledge of the future jobs or the required processing time of jobs that are not yet completed. We want to minimize the total response time, i.e. the sum of times each job takes from its release to completion.

One particular algorithm, Balance, always schedules the job that was least processed so far. A comparison of an on-line scheduler running Balance against the optimal off-line shows a very large competitive ratio if both algorithms use machines of the same speed. However, if Balance is run on a faster machine than its clairvoyant competitor then the competitive ratio drops. In other words, sufficiently high speed is more powerful than clairvoyance.

**11/9/98 - Music and Mathematics: Why Is It Impossible to Tune a Piano?
**Robert E. Jamison

Department of Mathematical Sciences

Clemson University

The pitch of a musical tone depends on its frequency -- that is, the number of vibrations per second. Two musical tones played together, or one right after the other, produce a musical interval. The quality of the interval is determined by the ratio of the two frequencies involved. It was an important discovery of Pythagoras in the 5th Century BC that the important musical intervals were associated with simple ratios of small whole numbers. For example, the octave is 2:1, the perfect fifth is 3:2, and the major third is 5:4.

In this discussion we will examine intervals in several contexts: as diagonals of a regular dodecagon, as functions which change one note into another, and as functions which change one frequency into another. If we examine the patterns formed by repeating a musical interval, we will arrive at star-polygons within a dodecagon. If we interpret these as compositions of functions, then we can see a remarkable consequence of the Fundamental Theorem of Arithmetic -- namely, it is IMPOSSIBLE, even in theory, to ever tune a piano so that all intervals are in tune.

**11/2/98 - Packing of the Complete Symmetric Digraph with Orientations of a 4-Cycle
**Coleen Huff

East Tennessee State University - Kingsport

We first note that there exist four orientations of a 4-cycle: X, Y, Z, and C4. This paper gives the necessary and sufficient conditions for an X-Decomposition of the complete symmetric Bipartite graph KDm,n and also a Y-Decomposition of KDm,n. We then use these results to give necessary conditions for an optimal packing of the complete symmetric digraph KDp with each orientation of a 4-cycle. Finally, we show these necessary conditons are sufficient through direct constructions.

**10/26/98 - Objects and the Software Development Life Cycle
**Charles B. Williams

Template Software inc.

Mr. Williams is the co-author of a book entitled "Use Cases Combined with BOOCH, OMT, UML: Processes and Products." This book introduces a complete Object-Oriented system and software development process. Mr. Williams will be discussing some of the material in his book and how its contents relate to Software Development in industry.

**10/19/98 - Using Java to implement and test language learning strategies:
Should I learn 30 and 4? or 34?
**Craig Miller & Mike Onofrio

Dickinson College

This past summer, we worked together investigating different strategies for practicing the comprehension of spoken foreign words and phrases through the aid of computer software. Our focus was on the recognition of French numbers and the extent to which learners should practice recognizing compound numbers (e.g. 43, 65, 89) as opposed to simple numbers (e.g. 3, 5, 30, 60). We will present our software for practicing the comprehension of spoken numbers, some difficulties in implementing it in Java, and how we used it to evaluate two opposing strategies. We will finish with some preliminary results and their implications.

**10/12/98 - Web Programming: A Look at the Relationship of Three of the Most Common Tools of the Trade
**David Ward

Workshop Physics Project

Dickinson College

As the internet and the world wide web grow with popularity, so does the desire to create new and exciting web sites. We will examine three of the most common tools used by web programmers: HTML, JavaScript and CGI. Learn how they interact with the world wide web and with each other. See how simple things can change the whole look and feel of a web site.

**10/5/98 - Student Summer Experiences
**Joe DeRobertis

Senior CS Major

Dickinson College

Joe will be talking about 2 internships that he has had. He will focus on the first one in which he designed and created a web site for a software company. He will also talk about what he really didn't like about the company and some of the things that are different about working for a small company.

Dan Kurtz

Senior CS & Physics Major

Dickinson College

Dan spent part of his summer working on a Back-propagation Neural Network. The goal of this network is to analyze Langmuir probe traces extracted from plasmas created in the Dickinson College Physics Department's Plasma lab. He will discuss how the Neural Network functions and some of its applications, in particular modeling non-linear functions.

**9/28/98 - A DECadent Summer
**Steve Hildebrand

Senior CS Major

Dickinson College

Steve will talk about his experience working for Digital Equipment Corporation this summer. Steve spent his summer working for DEC's UNIX Software Development Group in Nashua, NH. He focused primarily on writing software that controlled an automated test suite designed to exercise DEC workstations and servers. During his talk he will discuss the type of programming he did and perhaps more importantly, how a summer inside one of the world's biggest computer companies affected him. He will talk about corporate culture, the impact of a major corporate takeover, and other issues of interest to Majors as they prepare to journey to the "Real World."

**9/21/98 - You'll Know What I Did Last Summer
**Ray Brown

Senior CS Major

Dickinson College

Both of these speakers will talk about the work that they did over the summer. Ray was employed by the Navy in Mechanicsburg, PA where he worked developing data base applications using graphical development environments.

And if time permitsâ€¦

Grant Braught

Department of Mathematics and Computer Science

Dickinson College

Grant Braught was here in Carlisle all summer working on an Assignment System to allow students to obtain, complete and hand in assignments using the World Wide Web. He will speak about some of the benefits of such a system.

**9/14/98 - Career Services for Math & CS Majors At Dickinson College
**Jill Lawley - Dickinson College Career Services

Jill Lawley of Dickinson College Career services will talk about the services provided by the Career Center at Dickinson. She will focus on services that are particularly important to students in Math and Computer Science. She will also present information about the jobs obtained by past students and average salary information when it is available.

Jill will also talk about a career night at the Science and Technology Company (SCT). SCT is based in Philadelphia and is holding a career night on October 1, to meet with college seniors in the fields of computer science and mathematics. The possibility of a college sponsored trip to the SCT career night will be discussed if there is sufficient interest.