The Research Of Metadata Based On Learning-Resources Grid

With the development and the popularity of internet and computer, internet is increasingly becoming the platform of exchanging information and accessing knowledge for people, and the situation happened in the field of education. There are a large number of Learning-Resources in the web. And they are in different in form and format. It is hard to uniform and manage effectively. However, with the method of grid technology and metadata description, we can solve this problem. In this way, such resources can be integrated with the distributed resources and complexity of different kinds of resource information can be screened, thus realizing share of resources and information.Based on the analysis of the grid architecture and the functions of Learning-Resource Grid, analyzing the Five-level Sandglass Architecture and Open Grid Services Architecture of grid. The hierarchy structure of Learning-Resource Grid is designed and the principles of metadata schema in Learning-Resource Grid are provided. The hierarchy model of metadata in Learning-Resource Grid is constructed from the bottom to the top layer, and the model is consisted of Learning-Resource physical metadata, Learning-Resource Information-Transmission metadata, Learning-Resource virtual organization metadata, Learning-Resource service metadata and Learning-Resource user metadata. Meanwhile, the article sum up the resource belong to each layer which need metadata description.The article analyzed the standards in education resources metadata both here and abroad, including the IEEE LOM, Dublin Core and CELTS.Combining with the status of college education resources construction, the paper analyzed the educational resources metadata standard which established by Education Ministry Information Technology Standards Committee carefully. Referencing the CELTS Metadata Criterion, the thesis present the metadata description for Learning-Resource physical metadata layer, Learning-Resource service metadata layer and Learning-Resource user metadata layer based on the hierarchy model of metadata of Learning-Resource Grid.Finally, the article construct the environment of Learning-Resource Grid by Alchemi grid middle ware and analyze the advantages, architecture and components of Alchemi. Introducing the searching process under the environment of grid. Storing the Learning-Resource information, service information and user information in distributed data-base by metadata description for searching. Verify the feasibility of metadata description under the grid environment.