A Systematic Approach to Design the Network - based LearningEnvironment for Home and O

An eeective network-based learning environment provides synchronous and asynchronous education to learners who are physically remote from or opt to telecommute to the base location of instruction. The environment provides content creation, user registration, course material storage, multiple delivery means, and end-user viewing tools. An intriguing aspect of the environment is how to model a lecture in terms of pre-, in-, and post-class information. We regard a lecture model collectively as an activity consisting of three elements: lecture materials, lecture presentation, and lecture interaction. These elements have their semantic meanings and relationships. The lecture model deserves a formal speciication to describe its behavior and a structural representation in the hypermedia repository to organize the presentation information so that it can be truthfully reproduce in an asynchronous learning environment. We derive the synchronization speciication for the media objects and deene Strong-Weak Networked Hyperlink (SWNH) to represent the lecture structure and inter/intra media object reference in the distributed network environment. The speciication and representation exhibit an object-oriented modular design, which is simple, but powerful enough, to aid on policy decisions such as prefetching, caching, and versioning control. The presentation of the lecture embody both the event-driven and timeline-based presentation synchronization where the browsing and authoring tools developed earlier t right into the learning environment, e.g. FLIPS and HQT by the authors, or are immediately available through other providers, e.g. Web browsers.