In the past decades, the Internet has evolved so rapidly that it makes the information-technology industry grow extremely fast. Internet-based applications such as e-commerce, e-payment, e-billing, e-learning, and so forth have tremendous influence on society: There is a trend that our society will be reshaped by the Internet. Among these applications, e-learning is one of the killer applications. Currently, the traditional education system faces some challenges that arose from the development of the knowledge-based economy. School enrollment increases with the population growth, education levels also increase for the new economy, and the cost of higher education escalates. On the other hand, in the workforce-training market, as the information economy develops, the demand for skilled workers increases. As the technology keeps changing, the workforce needs continuous training to maintain its productivity level. Hence, both formal school-based education and continuous workforce training have become big business now, and they will be even bigger in the future (Kerrey & Isakson, 2000). A more sophisticated education model is required to take this challenge, and so e-learning came into being. Compared to traditional classroom teaching, e-learning provides one major advantage: It makes the access of information much easier and more convenient. Hence, it makes learning of all kinds, at all levels, anytime, anyplace, at any pace a practical reality (Kolar, 2001). E-learning also gives tremendous cost savings for both instructors and learners; the learning model is shifted from instructor centered to learner centered, which focuses primarily on the needs of learners. The updating of online material is also much easier. Many e-learning systems can develop personalized and interactive applications that allow users to customize their e-learning models to their own pace, and they can truly engage the user in that they involve the simulation of real-world events and sophisticated collaboration with other learners and instructors (Quah & Chen, 2002). In our e-learning system, we incorporated mobile-agent technology to enhance the response time of information retrieval. The purpose of this incorporation is to overcome the bottleneck problem faced by many pure client-server-based systems. Since mobile agents are able to traverse from one information server to another autonomously to search for relevant documents for users, only relevant articles are sent back. This saves bandwidth and enhances the efficiency of the e-learning system. As a result, the turnaround time for user queries or information searches reduces, and the feedback from the user community is positive as the response time is shorter and users find it easier to maintain their trains of thought in their study.
EVALUATING PRODUCTIVITY OF DISTRIBUTED KNOWLEDGE-BASED SYSTEMS
