| With the rapid development of information technologies, metadata technology is becoming more and more important as one of the main technical supports of digital earth strategy. Geospatial metadata is the background information which describes the content,quality,representation,spatial reference,management and other appropriate characteristics of spatial datasets. It is helpful for users to understand,discovery,locate,mine,evaluate and maintain these spatial data. The target of this paper is to have a research on the content and organization of Geospatial metadata, to design and develop a management system for Geospatial metadata with the ability to collect,store and search them.The paper first summarizes the spatial metadata basic concept, reviewed the metadata engineering research domestic and foreign present situations, and introduced FGDC and the ISO two spatial metadata standard, but also has carried on the simple analysis to three typical metadata system. Then pointed out the metadata technology, the computer technology, the GIS technology and so on in close integration with development tendency, set the topic research goal and the significance.The spatial metadata needed to use very many related technologies according to the server realization, the paper to the metadata according to the storge, publishing, transmission exchange and distributional retrieval has carried on the analysis and the summary. Because the XML technology vigorous development by and its in aspect and so on data expression, transformation, transmission, inquiry displays many merits, therefore it in metadata domain already by widespread application. Therefore this article to the XML technology, specially with metadata system relations close XML, XML Schema, XSLT and so on has made the detailed introduction. The metadata storge and distributional retrieval technology for the system two big cores function, have separately carried on the thorough analysis and the discussion, had pointed out each kind of design thought merit and the existence question, had basically expounded metadata question and its solution and technical route which faces according to the server design and the realization. The C/S pattern already were unable to adapt the distribute system design and the deployment request, but N-tier system structure was allowed very good to satisfy the spatial number according to the server various aspects overhead construction demand. The J2EE recent years mature enormously promoted the development of N-tier system structure, and have become the standard platform of server-side software construction, can the very good solution system overhead construction and in function realization each kind of ifficult problem, therefore carried on the system introduction, the centralism discussed it at business, the security, the colony and the loading blance aspect superiority. Then based on XML and the J2EE technology, proposed the metadata server system design frame. The paper briefly introduced all subsystems function, and in detail planned and has designed the system module.The metadata storge and the distributional retrieval realization are the system development key point. This article first the multianalysis table mapping plan principle and the existence question, and proposed the union object mapping mentality, uses the O/R mapping the new realization plan. Because the table mapping only is suitable in the compatible existence relations table metadata, this article proposed the tree analyzes the new plan, through according to withdraws the structure information and the content information from the XML metadata, then separately goes into storage the method thorough settlement other plans face to complex Schema support difference and performance low difficult problem. The spatial metadata designs according to the distributional retrieval based on ZING. ZING is Z39.50 unifies the Web service technology, the simplification and rerefines after the product. The article first was briefly introduced ZING core service - SRW, and re...
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