Research And Realization Of Management Of Geospatial Metadata In MAPGIS7.0

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 such functions and services as storage, compilation, query and synchronization with the spatial data set, to realize Geospatial metadata management in the national excellent GIS software, namely MAPGIS 7.0.We first review the current situation of metadata technology, and point out the tendency of close combination of metadata technology with computer technology and GIS technology. Then we conclude the relevant concepts of Geospatial metadata, study its content composing and its configuration mode by analyzing and comparing several metadata standards that are applied widely, and educe the common characteristic of Geospatial metadata standards. Also we analyze three existing systems with emphasis on their architectures and their implemental strategies, they provide the all-right reference for the system realization. For the sake of flourishing development of XML and some advantages that it shows in the data representation, transfer, transmission and query, it will have a wide range of applications in the metadata field. So we introduce such XML technologies especially have consanguineous relation with the metadata system as XML 1.0, XML Schema, XSLT, XPath and DOM. In succession, we bring forth the infiltration of XML technology in the metadata system by a picture.Metadata storage is one of the absolutely necessary constitutes of the metadata management system. Owing to the system adopts XML as the format of metadata, the problem on the metadata storage also becomes to the storage of XML. In the first instance, we probe into all kinds of XML storage technologies that are existent for the moment, analyze the strongpoint and the shortcoming of every technology. And then we start with the practical application, with a view to the characteristics of MAPGIS 7.0, we put forward a sort of new solving scheme, namely tree type split, in which we consider relative database as storage medium, the efficiency of...