Research For The Hypermap Model Based On XML

With the stratagem of "SDI" and "Digital earth" entering new century all the world, map also enters the digital map network era."Digital China" and "NSDI" are being developed energetically in our country. All of the basic space information service network and GIS need the support of "Digital map" or spatial data integration. As a result, it is very important to researching a new and high capability hypermap model based on network. XML is the effective means of constructing the hypermap model. The key research contents: (1) the establishment of spatial data model: Based on analyzing the basic feature and the excellent-shortcoming of traditional data model, this paper presents a hypermap spatial data model based on GML. Through analyzing the shortcoming of current metadata representation, presents a new description the metadata of spatial data based on RDF. (2)The design of hypermap data structure: the hypermap has much graphics data and non-graphics data, the paper discusses how organizing the data to save the space, to improve the speed of saving and dealing, to be convenient for user to controlling, computing and displaying the hypermap data.(3)the hypermap structure model: based on Dexter reference model, combining with the distributed method, the paper presents the three layer structure model of distributed hypermap and expatiates the detail function of per layer. At last, a example of interactive hypermap about a province population investigation subject map base on SVG is realized to validating the data model and the data structure. The result shows that the data model is true and distributed spatial data integration, may exchange spatial data, realize the share and inter-operate of data. The data structure is hyper-link, convenient for managing the hypermap data.