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this paper research on spatial information service laws of development and application from angle of model and put forward the basic conception of spatial information service model basing on information service model. It presents a complete structure of model, and detailedly explains elements, the main characteristics and principles of interaction. Consider that the reciprocity between the various elements is the main inner factor which can produce a variety of different services type, and thus lead to different spatial information services with a variety of different forms. At last this paper accord to the relationship between the inner factor and elements to bring forward the abstract services classification results which currently can cover almost all the spatial information service types, and give theoretical support.

In order to provide an access method which is independent of the specific data structure and file formation, in this paper, the design and implementation of GDE(Geographic Data Engine) is discussed based on the research of geographic data modeling course. The research of GDE is the GIS applied Platform design based on geographic data modeling and data structure driving. Related theory involved GDE and design tactic have been discussed conceptually and the implementation of GDE model has been presented.

This paper presents a new method to describe the relationship between services, which refers to the basic concepts of geometric topology. It uses the relationships between points and lines to describe that from input and output information flow in the service, further to produce a static invoking relationship between services. According to this abstract relationship between the points and lines of the spatial information service, it can generate a valid topological relationship between the services with point elements, line elements and topology relationship tables. The topological relationship between services can put into one-to-one relationship with information processing each process, and thus can improve the speed and performing efficiency of the service combination and matching. This article defines a concept of the point elements and line elements in the service topology, describes the properties of the elements, sets up four kinds of topological relationships and their corresponding information process. A proposal of the method of establishing topological service description is provided. Ultimately there are specific examples to represent the construction process of services topological relationships and their final results.