Object-oriented Spatial Data Model And Data Server

With the development of GIS(geographical information system),distributed spatial data servers will play an more and more important role in it.But the existing GIS,which are mostly based on C/S software architectures,have poor ability to share,orgainze,manage spatial information.On the other hand,nowadays the GIS already have the ability to store,manage spatial data.Most of the GIS are centered on spatial data.But they have poor ability to express objective geographical world intactly, perform high-level space analysis and put forward the decision scheme directly.The key reason is the traditional spatial data model can't describe the world exactly.The paper is based on the problems mentioned above,mainly makes the research on encapsulation of spatial data access.Acting as the kernel of GIS,spatial database provides spatial data storage,access and other application.CORBA based spatial database access makes a solid foundation on implementing interoperation between heterogeneous GIS and distributed,component based GIS.It focuses on the organization and storeage of the spatial data,the architecture of the system,the logical design of the spatial database,and the design and implement of the distributed spatial data server.The paper is organized as follows:firstly,the research background of the distributed spatial data server and the development conditions of it are discussed,then the key technologies and theories of the distributed spatial data server, which includes OOSDM(object-oriented spatial data model) , Middleware ,ORDB(object-relational database),Geodatabase,and OpenGIS.The following discusses the desgin and implement of the distributed spatial data server with the technologies and theories introduced above.Finally is a example of the distributed spatial data server,the result shows the system has reached the aim of the design.