The following article is a component of the May 1998 (vol. 50, no. 5) JOM and is presented as JOM-e. Such articles appear exclusively on the web and do not have print equivalents.

Multimedia Tutorials for an Introductory Course on the Science of Engineering Materials

C.J. McMahon, Jr., Ransom Weaver, and Seamus S. Woods

CONTENTS
INTRODUCTION THE TUTORIALS Navigation Controls Chapter Topics Animations STUDENT EVALUATION DEBUTING THE FIRST CD-ROM ACKNOWLEDGEMENTS

The University of Pennsylvania is in the process of constructing a one-semester set of interactive multimedia tutorials that are being disseminated to students on CD-ROM and a local network for a course in introductory materials science and engineering. The topics that have been completed include dislocations and plastic deformation, phase diagrams, magnetic materials, and electronic materials. They are linked to the interactive glossary that is currently available on CD-ROM. Our goal is to replace the lecture part of the course with studio exercises for which the tutorials will be required preparation. As they are produced, the tutorials will be made available at no cost to instructors for use on local networks so that they can be evaluated. This article describes the tutorials and the animation player that is included with them and will give examples from tutorial sections and the animations. This work is sponsored by the National Science Foundation under grant DUE 94-55333.

INTRODUCTION

• The topics, terminology, and even the way of thinking are new to most students.
• A standard science/engineering approach emphasizing formulae and numerical calculations can leave introductory-level students without a grasp of the basic principles of structure/property/processing relationships that are at the core of the subject.
• An understanding of many of the topics requires the visualization of three-dimensional moving images or evolving processes that cannot be presented effectively using static illustrations.
• Students, particularly non-materials science and engineering majors, find a traditional lecture series that builds from electrons to atoms to crystals, etc., difficult to absorb.
• Students typically exit a lecture without real comprehension of what was presented, because they were not able to pass the information from working memory to long-term memory at a rate commensurate with the delivery rate.

To address these issues, the University of Pennsylvania is developing a multimedia-based course for introductory materials science and engineering that serves as both a comprehensive one-semester materials education course for non-materials science and engineering majors and as an introduction to the subject for prospective future topic majors. The course employs computer-presented tutorials that can be utilized in several ways: as a replacement for classroom lectures in courses where the class meetings are devoted to studio-type active learning, as a supplement to classroom lectures that are illustrated by the animations provided, as a basic course in institutions where faculty from other branches of science or technology serve as coaches for materials science and engineering, or as a self-study course for those who must pursue the subject on their own.

A demonstration of the tutorials is available for download. The demonstration consists of three pages from the chapter on phase diagrams: the lever rule, relative amounts of and , and solute redistribution. The demonstration module is available in both Macintosh format as a binhexed self-extracting archive (3.3 Mb) and Windows format as a zipped file (2.9 Mb).

The tutorials can be played directly from a CD-ROM on either Macintosh or Windows-based machines; also, the compact disk can be copied to the hard drive of the computer for enhanced performance. Alternatively, the tutorials can be delivered from a server on a local network (with appropriate permission by the authors).

This project is attempting to face the challenges of introductory-level courses by putting the entry-level transfer of information at the disposal of the student, who can then control the pace of delivery, including the ability to stop and re-play portions of the lecture that seem unclear at first. A dissenter might say that this is supposed to be the function of a textbook, and it is true that a small fraction of students can use a textbook effectively for this purpose. However, experience shows that most students are unable to do this, whether for reasons of time, motivation, ability to absorb new information from a printed medium, or others. In any case, a textbook is a mono-medium that has great difficulty in presenting moving or evolving processes.

THE TUTORIALS

Figure 1. The chapters in the tutorial.	Figure 2. Each chapter is divided into sections.

To develop a tutorial, an initial version of the script and a storyboard for the illustrations are developed first; the next step is constructing the animations. Next, the script is revised to adjust to the final form of the animations; the cues for the illustrations are inserted; the script is recorded; and, finally, the audio, illustrations, and other components are integrated in the finished tutorial.

Figure 3. Pages are identified and accessed by tabs that display a yellow subject blurb at the top of the page.	Figure 4. The pages are designed like a lecturer's blackboard, where the instructor would normally write key words or concepts.

As in a book, the tutorials are divided into chapters (Figure 1), and each chapter is divided into sections (Figure 2). Each section contains up to 25 screens called pages, and any page can be identified and accessed by way of the tabs that display a yellow title at the top of each screen (Figure 3). The interface is a blackboard on which the navigation controls; the words or phrases that a lecturer would typically write on the board (Figure 4); and the diagrams, photographs, animations, video clips, and derivations that appear during the play-through presentation of a page (Figure 5) are displayed.

a	b
c	d
	Figure 5. Several features are used during the audio presentation of a page, including (a) diagrams, (b) photographs, (c) animations, (d) video clips, and (e) derivations. A QuickTime video clip (4 Mb .mov file) and an audio file (258 kb .au file) from one tabbed segment in the recording and magnetism section (Figure 5d) can be played now.
e

At the end of each section is a set of questions for review (Figure 6), and the answer to each question can be seen by clicking on the question. Every page is linked to the interactive glossary (Figure 7), so that the student can look up any term that is likely to need some further explanation. Any page may be marked as a place holder or for review, and this is saved between sessions in a preference file.

Figure 6. Each section contains a set of review questions to conclude the presentation.	Figure 7. A sample screen from the interactive glossary.
a	b
Figure 8. Presentations can also be played while viewing just the (a) illustrations or (b) text.

Navigation Controls

Chapter Topics

• Corrosion
• Tensile Behavior
• Microstructure and Crystallography
• Dislocations and Plastic Flow in FCC Metals
• Annealing of a Cold-Worked Metal
• Fatigue and Fracture: Behavior of BCC Metals
• Phase Diagrams: Wetting, Capillarity, Brazing/Soldering
• Transformations in Carbon Steels
• Hard Materials: Friction, Wear, Hardened Steels, Surface Hardening, Ceramics
• Precipitation Hardening: Aluminum-Alloy Bike Components
• Design of Bicycle Frames: Materials, Joining Techniques
• Polymeric Materials: Tires
• Composite Materials: Fibers, Network Polymers, Application to Frames
• Magnetic Materials as Employed in the Walkman
• Electronic Materials

The topics in boldface are complete and comprise the content of the first CD-ROM; the interactive glossary is also included. The topics in italic are presently under development and will comprise the next CD-ROM, which is anticipated for release in early 1999.

Animations

A demonstration copy of the animation player is available for download. Featured are examples from the chapter on dislocations and crystal plasticity. The player is available in both Macintosh format as a binhexed self-extracting archive (1.4 Mb) and Windows format as a zipped file (1.2 Mb).

STUDENT EVALUATION

Nevertheless, an analysis of the questions on the final exam showed that the average score on this material (62) was not much different from the average for the material covered in the lecture format (67), which had been covered at the normal pace and had mostly been treated in the two-hour exams during the term. This early version of the compact disk lacked some of the refinements added later, such as the slider (the red ball shown in several figures) and the question-and-answer list at the end of each section (Figure 6). Given the students' responses, it was concluded that the approach was feasible.

The improved version of the chapter on magnetic materials was tested by a group of volunteer students who had no prior knowledge of the material during the spring term of 1998. Four students learned the material (in a preliminary way, as they probably would have in preparing for a studio class) by using the CD-ROM, and four others learned it from the textbook. All eight had access to the question-and-answer list—four on the CD-ROM and the other four in printed form. They were given a test comprising ten of the 61 questions on the list. The averaged scores were 59 for the CD-ROM group and 56 for the textbook group. Given the small sample size, the difference is not statistically significant. The real difference came in the averaged estimated time that each group spent on the subject: 3.1 hours for the CD-ROM group and 4.1 hours for the textbook group. In addition, the former group expressed a preference for learning from the CD-ROM over the textbook method in a follow-up questionnaire. This provides encouragement that the multimedia tutorial will be a viable method of getting students to prepare for the studio classes, which would depend heavily on prior preparation. (Of course, some coercion will presumably be needed and applied in the form of short daily quizzes.)

DEBUTING THE FIRST CD-ROM

ACKNOWLEDGEMENTS

ABOUT THE AUTHORS
C.J. McMahon, Jr., earned his Sc.D. in physical metallurgy at Massachusetts Institute of Technology in 1963. He is currently a professor in the Department of Materials Science and Engineering at the University of Pennsylvania. Dr. McMahon is a fellow of TMS.

Ransom Weaver earned his B.A. in literature at the University of Pennsylvania in 1990. He is currently a graduate student in Arabic studies at the University of Pennsylvania.

Seamus S. Woods is an undergraduate in the Department of Materials Science and Engineering at the University of Pennsylvania.

For more information or to acquire a complimentary copy of the CD-ROM (instructors only), contact C.J. McMahon, Jr., Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104; (215) 898-7979; fax (215) 573-2128; e-mail cmcmahon@lrsm.upenn.edu.

To order the first CD-ROM (Introduction to Engineering Materials: The Bicycle and the Walkman) after it has become available, contact Merion Media, c/o Whitman Distribution Center, 10 Water Street, Lebanon New Hampshire 03766; (800) 353-3730; fax (603) 448-2576.