| With the development of GIS(Geographic Information Systems) and computer network Technology, and the popularization of Internet, the handling of geospatial data has been intergrated into all kinds of special domains, such as land management, electric power, telecom, city pipeline network, irrigation works, fire protection,traffic, city planning and etc. The massive DGIS(Distributed GIS) has great meaning to share and interoperation of geospatial data, share and distributed processing of geographic operation services, and integration of domain application. Realization of incorporate, great capacity store of geospatial and aspatial data, efficient spatial query and spatial analysis, and effective distributed management and computing of geospatial data, are all the important features and key technical problems to be answered.This paper does a deep research of the above key technical problems of DGIS, and a thorough discussion of the design and realization of distributed spatial information' efficient spatial query and spatial analysis systems.The paper consists of seven chapters. The first one is forward. It discusses the research background, the purpose and meaning of the research, and the research trends outside and inside.The Second Chapter introduces the defmation and characteristics, architecture models, main technology and development.The deep research of spatial query and spatial analysis algorithms in DGIS is done in Chapter Three. At the same time, spatial access methods, namly spatial indices, are also investigated in detail in order to advance the efficiency of spatial query and spatial operations. Based on the development, classification, comparation of classific algorithms of spatial indices, the paper designs two efficient spatial indices including the improved quadtree and R+tree, applies them into spatial query processing, and realizes the spatial select query algorithm based the improved quadtree and R+ tree, and nearest and k-nearest neighbour query based R tree. Powerful spatial analysis ability is the important feature of GIS different from other management information system. The paper puts forward an efficient buffer generation algorithm-recursion algorithm; simultaneously, introduces the above two spatial indices to the handling of map overlay, and gives the improved quadtree-based and R+ tree-based vector map overlay analysis algorithms individually. The result of test shows that algorithms above are effective and feasible, and integrated into GeoBeans 5.0.The fourth chapter introduces a distributed spatial database prototype system-DSDB through the discussion of relative theories such as the combination of GIS and database, the mode frame, design method, and key technology of distributed spatial database, and etc. Based on database access technology-ADO, a prototype system of distributed spatial database engine based on ADO, named ADO-SDE, is developed and looked on as the middleware accessing DSDB, providing the data interface between user and spatialdatabase.Based on the OpenGIS SQL specification, the fifth chapter designs and realizes a spatial database query language named GSQL(Geographic Structured Query Language) through expanding spatial data typies, providing the powerful spatial operators, and extending spatial operation. And the sentence expression form and excuting process of GSQL is described detailedly. A friendly, simple, and easy used GSQL query interface is designed, which is composed of some icon buttons and comoboboxes, and basically has query function with complicated spatial analysis operation.Through the discussion of the theories of new-generationed distributed computing model-Web Service, such as its defination, theory model, technical system, comparation with traditional distributed computing model, and the concept of geospatial information web service, and the detailed research of the web service developing tool of Microsoft-Microsoft SOAP Toolkit 3.0 and its realization mechanism of building web services, the sixth chapter gives an efficient...
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