【作者】 李明勇；

【导师】 马燕；

【作者基本信息】 重庆师范大学 ， 课程与教学论， 2008， 硕士

【摘要】 21世纪是人类全面进入信息化社会的伟大时代,教育信息化、数字化建设也在不断深入,各类教育资源将会越来越多,并呈指数级增长。但是当前的教育资源建设普遍存在如下一些问题:优质资源较少,存储分散,缺乏广泛的资源合作;远程教育标准不完善,网络存在大量的异构结构;教育资源不能大范围内共享,利用率不高,重复开发现象严重;资源检索的技术智能化水平不高;资源的获取和应用及更新速度慢,动态适应性较差等。其中主要问题还是没有形成资源的有效共享。网格技术的出现,使资源的完全共享有了实现的可能,因为网格的本质就是资源的全面共享。网格具有在教育领域有广泛应用价值的特性:共享性、动态性、异构性、超级计算性能、强大的服务支持等。网格技术革新了传统资源共享的弊端,使教育资源能够全面共享,异构系统互操作再无障碍,网格创新了“服务”的概念,对学习者提供按需服务。教育资源的注册和发现是教育资源有效共享的核心和基础。只有在资源注册和发现的基础上,其他应用才可能实现。本文首先简述了网格技术的定义及特点,分别论述了三种流行的资源元数据描述标准,并提出了一种改进的教育资源的元数据描述。在已有发现机制的基础上,提出了一种基于层次的教育资源分类注册与发现方法。最后给出了教育资源注册及发现算法,并使用GridSim进行了仿真测试。更多还原

【Abstract】 The 21st century is the great time that the humanity enters information society comprehensively, the informatization and digitalization of education is also developing in depth, and various educational resources will be increasing in number, and will be growing exponentially. However, the following common issues exist in the current educational resources building: the lack of excellent resources, dispersed storage, the lack of cooperation within a wide range of resources; the imperfection of Distance Education Standards, the presence of heterogeneous structures in the networks; the inability of sharing educational resources within large scope, the low utilization rate, the serious problem of duplication development; the low intelligence level of resources retrieval techniques; the slow access, applications and updating of the resources, the poor dynamic adaptability and so on. The main problem underlying is the ineffective sharing of resources.The invention of Grid technology, given that the essence of grid is comprehensive resource sharing, makes the sharing of resources with full realization possible. Grid has a lot of useful features which have broad applications in the field of education: sharable, dynamic, heterogeneous, superior computing performance, and outstanding service support. The Grid technology has eliminated the drawbacks of traditional ways of sharing resources, and enabled comprehensive sharing of educational resources and full accessibility to heterogeneous system interoperability. Grid has given a new meaning to the concept of "services", to provide on-demand services to learners.The registration and discovery of Educational resources are the core and foundation of the effective educational resources sharing. Without the registration and discovery of educational resources, none of the other applications can be possible. This paper gives a brief description on the definition and features of the grid technology, discusses respectively the three popular standards of resource metadata descriptions, and proposes an improved educational resources metadata description. Based on the mechanism already known, a new way of resources registration and discovery which is based on levels is presented. Finally, this paper presents the algorithm on resources registration and discovery, and runs the simulation tests using GridSim.更多还原