| The development of grid technology not only has brought the opportunity for geospatial information science, but also has made it faced the challenge at the same time. The traditional geospatial information system has a serious problem, which is fail to solve the effective sharing well and utilization of geospatial resources fully, just some implementation of geospatial resources share (such as geospatial data share) can I perform. But the grid emphasizes is fully sharing of resources and integrative management of resources share. This dissertation regards 3D geospatial information application as research field, and attempts to improve the enviorment of geospatial share and application by grid technology. The services-based application mode provides 3D geospatial information application services and services combination for users transparently. Among these services include 3D geospatial data service, 3D modeling service, visualization service, geospatial analysis service, etc. With these services, geospatial information share and interoperability can be implemented. It is convenient for heterogeneous environment or heterogeneous system integration and application, serving the construction of digital city better.This dissertation is launched around the theme which is 3D geospatial information application based on grid computation. The main research contents and results are as follow:The main support technology and frame system of 3D geospatial information application grid was studied. Including:â‘ Describe the relevant concepts of Grid GIS in detail, including the concept of grid, Spatial Information Grid (SIG) and Grid GIS. Discuss the main support technology, including OpenGIS, Web Services and OGSA.â‘¡ Review and summarize the existing Grid GIS architecture. According to the characteristics of 3D geospatial information application, a 3D geospatial information application grid frame system was proposed. Based on services, the frame includes 6 layers from top to bottom, which consists of application layer, combination layer, services layer, share layer, data layer and foundation layer. Each layer is interrelated, which has the function of the 3D geospatial data management and 3D geospatial data interoperability and 3D geospatial information application.The 3D geospatial data management based on grid was studied. Including:â‘ Discuss 3D geospatial data storage management and metadata management. For storage management, distributed storage, gathered storage and buffer storage were discussed. For metadata management, the registry management and data replica management of 3D geospatial data were emphasizelly studied. In the meantime, the metadata management method based on metadata database was proposed, the framework of metadata management, the metadata registry information table and replica management information table were designed. For replica management, the replica establishment tactics, consistency maintenance method of replica, replica chosing and replica deleting have been discussed.â‘¡ According to the characteristic of the frequent data transmission under grid, many kinds of griddata transmission methods were discussed. In order to realize the security, reliability and high efficiency of grid data transmission, we need a common transmission protocol. Globus project proposed a grid transmission protocol, which is GridFTP based on standard FTP. At the same time, GridFTP has expanded FTP, realized the support to many kinds of storage systems and offered the united access interface for uses. Therefore, the characteristic and advantage of GridFTP were stressed.(3) Because the geospatial data exists many kinds of complicated characteristic such as the heterogeneous environment and the heterogeneous data source. So, realizing the geospatial data access and integration under grid environment should be studied. Introducing OGSA-DAI middleware to 3D geospatial data access and integration was proposed. Adopting grid data service to implement 3D geospatial data aceesss and integration, which offers a kind of new mode of access and integration for heterogeneous database.> The 3D geospatial data interoperability method based on grid was studied. Including:? Analyse the geospatial data interoperability method based on GML technology, which is very difficult to adapt to 3D geospatial data interoperability. Therefore, a method based on 3D geospatial data message package and offered 3D geospatial data interoperability by grid service was proposed. In this method, message package has been divided into message head, message body and attachments logically. The parts of message package are mapped to SOAP head, SOAP body and SOAP attachments respectively. Message head contains 3D geospatial data metadata information. Message body contains vector data of feature boundary and attribute data of geospatial interrelated. Message head and message body accord with XML/GML specification. Message attachments contain texture data or 3D model data.? Design the objects and interfaces of 3D geospatial data grid services. Then discuss the concrete implementation method of data query, data packing, data unpacking in the objects. The procedure of the geospatial data share and interoperability implementation method in the client side by grid service was discussed. Finally, the feasibility of the proposed geospatial data interoperability method through a test instance has been verified.> The 3D geospatial information application based on grid services was studied. Including: CD The main research contents of 3D geospatial information under grid environment were defined,which contains 3D modeling, 3D visualization and 3D geospatial analysis. Then discuss and analyse some key technology involved in 3D modeling, visualization and spatial analysis.(2) Discuss the design mode of 3D geospatial information grid services in detail. Then provide the UML design diagram of geospatial information grid services. Focus on the characteristic of 3D geospatial information application services, the author proposes to adopt the mode of mixing of inheritance and delegation to design grid service, which is easy to promote the feasibility and usability of 3D geospatial information application services.(3) The registry and discovery mechanism of 3D geospatial information services were discussed in detail. To large-scale grid application, the author proposes to introduce UDDI to grid services management, implement grid services registry and discovery by UDDI. To small-scale grid application, WS-Inspection to the discovery of grid services, issue grid services to WSIL document were introduced briefly.? The services chain model of 3D geospatial information application was discussed. In 3D geospatial information application grid, services chain model is a flow model in essence. Therefore, we can make use of business flow modeling techonolgy to deal with services chain model. Petri net is a kind of famous business flow modeling techonolgy. As a result, this dissertation has introduced Petri net to 3D geospatial information application, proposed a new services chain model based on Petri net.(5) The 3D geospatial information application mode based on grid services was proposed. It is a service-based application mode, which can provide different granularity and different function combination serives. It is convenient for information sharing and interoperability, function integration among heterogeneous systems.> A prototype system (GridVRMap) based on 3D geospatial information application services has been set up. The experiment has been carried on to verify to some archievements of research.All the work in this dissertation represents certain use for reference to the research of 3D geospatial information application services based on grid computation, which can be useful for further relevant research.
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