Design And Part Implementation Of A Component-Based Geographical Information System

Vehicle Cruise System Development Environment (VCSDE) is a project of an information system company whose core technology is the Geographical Information System. VCSDE1.0was developed based on the Maplnfo and combined with Spatial Reasoning, Spatial Decision Support System and GPS. During application of VCSDE, the disadvantages of VCSDE which included the disability of analyzing the topological relationship between the graphical elements, the limitation of spatial analysis function and the high price hinder the spread and the action of commercializing. The goal of our work is to solve these problems and the overall design and part of the implementation of some subsystems of the Component Based Geographical Information System (CBGIS) are finished which is the key part of VCSDE.First, the overall design of CBGIS is presented in detail. Second, the design and realization of the Data Transformation Subsystem are introduced. The subsystem can transform the format of ARC/INFO, AutoCAD and MapInfo into the data format that the CBGIS needs. Third, the Attribute Management Subsystem built on SQL Server and ADO is given. It implemented the functions of Insert, Delete, Modify, Search and Browse. Also, the creation and maintenance functions of the attribute data table are realized. Finally, based on the existing representation method, semantic match, semantic space and the concept of the semantic inclusion of the fuzzy data, an approach to deal with the fuzzy data in the attribute relational database is provided.Our work is developed with VC++in the environment of Windows which has been combined with other subsystems of CBGIS and performed well. The future work is to maintain and improve the functions of CBGIS and to make the system much stronger, steadier to meet the users’ requests better.