Design Of The Distance Learning System Based On Grid Portal

Praised as the next generation Internet technology, the grid is a new trend of Internet after conventional Internet and Web, a new scientific computing pattern which connects all kinds of distributed and heterogeneous computational resources with the high-speed network to accomplish complicated computational problems. The grid integrates the whole internet into a virtual supercomputer, providing access of computational resources, storage resources, data resources, information resources, knowledge resources, specialist resources and the like for all.With the development of network and distributed computing technology, grid application expands from traditional scientific computing to other fields such as commerce, manufacture, war industry and education. OGSA enables the increasing integration of grid service and Web service, and the grid technology is tending to standardization. Today, a problem of grid application is how to use the developed application grid services easily, which needs to shield the grid's complexity and provides a convenient way for the users of grid services. As an important component of grid system, grid portal is a bridge connecting the grid user and the grid application. It provides a uniform interface based on Web browser to access and operate grid resources and services for the user, shields the complexity of the low-level grid, reduces the difficulty of using grid and accelerates the development of various grid applications.Modern distance education is one of fields that apply Internet technology earlier. With the development of computer network and the increasing richness of learning resources, people not only learn in various ways relying stronger on network day by day, but also develop a number of integral and practical distance learning/teaching system. However, these learning systems can't share learning resources with each other efficiently, because they are divided in management, distributed geographically and heterogeneous in running platforms. So developers of learning system pay more and more attention to develop distance learning system using grid technology. Research and design of the distance learning system based on grid portal will promote the utility of distance learning system, meet the requirement of sharing learning resources for web-based autonomic learning, cooperative learning and team learning, and promote the development of network distance education rapidly and remarkably.The distance learning system is a learning support system which services the distance learner, and it's also a system platform carrying out a variety of learning activities. The research and design to distance learning system should comply with related guidance of education and learning theory. From learning theory, theory of distance education, theory of knowledge management and other related theories, this thesis analyzes and researches the basic education theories affecting design of the distance learning system at large. It also analyzes and researches systematically the key grid portal technology, development and deployment of grid services for the distance learning system from key grid technology and key portal technology in depth. Then, further comprehensive research on grid resource management model, resource management based on Globus Toolkit and the management and sharing of learning resources in grid have been done. Based on demand analysis and research of distance learning system such as learning management, resource sharing and the personalization of learning system, it analyses the grid services which should be achieved, designs the distance learning system on the basis of grid portal and proposes its system model. Finally, this paper completes the development and implementation of the distance learning system portal, and accomplishes the development and deployment of a part of web or grid services.The main innovations in this article are: 1. Following the guidance of related modern educational theories such as the rich learning theory, distance education theory, knowledge management theory, instructional design theory, the distance learning system based on grid portal researches and designs the modern distance learning system comprehensively and systematically; 2. Advanced grid and grid-related technology are adopted to design the distance learning system, which is mainly used to solve the problem of " information isolated island" effectively and achieve a comprehensive sharing of distributed and heterogeneous learning resources; 3. Different learning groups or communities can develop, deploy and register respective grid learning services, and distance learners can dynamically discover and use these services, so it can bring about an effective integration of learning resources in the same learning system; 4. Combined with portal technology, on the one hand, the realization of a unified user authentication prompts learners to use all the learning grid services in grid easily. On the other hand, it meets the individual need of learners to learning system, such as customizing learning content, selecting appropriate learning interface, and customizing a variety of learning services.