BALTIMORE A Java-powered educational Web site at Johns Hopkins University offers fledgling EEs a chance to brush up on their electrical-engineering skills.
The site, Signals, Systems and Control, uses interactive demonstrations to provide tutoring on 20 difficult electrical-engineering concepts.
"We focus on the electrical-engineering concepts that are difficult to comprehend, such as convolution and closed-loop bandwidth," said Johns Hopkins professor Wilson Rugh. "By crafting Java-based demonstrations, along with traditional textual explanations, we hope to heighten understanding of these concepts with interactive tutorials and meaningful examples."
The Web site also includes 10 engineering tutorials for beginners.
Rugh's interactive tutorials are being used at several universities around the world as a regular part of their courses. The courses are also available on a CD-ROM from www.needs.org/engineering.
The most popular modules, Rugh said, are the "Joy of Convolution" demonstrations, in two versions: continuous time and discrete time. Each is based on a Java applet that mathematically executes a graphical convolution of signals on a computer screen. Once a student feels a subject has been mastered, he or she can take a multiple-choice test to gauge comprehension.
Another popular module is the "Harmonic Phasors and Fourier Series" Java applet. After a mathematical presentation on the various concepts, a technical presentation on the screen combines with an audio description of continuous-time phasors (rotating vectors in the complex plane).
The "Sense and Sensitivities" module includes a Java applet that demonstrates the utility of sensitivity and complementary-sensitivity functions.
Students who programmed the modules over the last six years include Steven Crutchfield, Mark Nesky, Kevin Rosenbaum, Hsi Chen Lee, Nabeel Azar, Andrea Dunham, Lan Ma, Christopher Hocker, Raman Venkataramani, Seth Kahn and Brian Woo.