Design and Development of an Interactive Web-based Environment for Measurement of Hardness in Metals: a Distance Learning Tool

摘要

An interactive Web-based experiment was designed as a preparation tool for students in the Materials and Mechanics Laboratory course at Texas Tech University. In the Web-based experiment, the students were given an introduction to the concept of hardness, what it means, how it is measured, and the calibration and utilization procedure using a Rockwell tester. In three semesters, three sections of the class were exposed to lectures but not to the virtual experiment and three sections (three groups) were exposed to both lectures and the virtual experience. Each group was given a pre-lab quiz to assess their understanding of the concepts and objectives of the experiment. The groups exposed to the virtual lab were also given a short quiz on the procedure of the experiment. The pre-lab quizzes were graded without prior knowledge of the students' section or group affiliation. Grades were compared between groups that were exposed to both the lecture and the virtual laboratory and those groups who were only exposed to the lecture. The average grade of the students in the lecture and virtual laboratory groups was approximately 20 % higher than that for the lecture alone group. This difference was statistically significant (p < 0.05) based on a t-test. The average grade on the knowledge of the procedure prior to actual experiment for the lecture and software groups was 75 on a 100 basis. Also, these students showed a great understanding of the hands-on procedure without significant input from the instructors. The lecture-only groups did not have a good idea of the procedural steps and required significant guidance from the instructor. Student evaluations of the software revealed that students were very enthusiastic about using the module as a pre-lab preparation tool but not as a replacement for the actual experiment. In this paper, the design of the software, important elements of the virtual lab and the evaluation results will be presented.