Design And Implementation Of Urban Underground Pipe Network System Based On Map Tile

With the increase of data concurrent access and map service in the urban underground pipe network system, the performance requirements of the GIS platform are also getting higher and higher. Map Tile technology can effectively ease the pressure of concurrent access map datas to the network transmission so that the interactive speed between server and client raises. But it is still restricted by the spatial service architecture, the map section production,the cache file retrieval and so on.In this paper, the research on the theory and technology of spatial geographic information web service standard and map tile technique is studied. It focuses on the key technology of REST software architecture and the multi-resolution hierarchical model and topological relations of map tiles, at the same time the differences of the two services caching mechanism based on OGC specification namely WMS and WMTS are compared and analyzed. It summarizes the slicing process in map tile technique and illustrates the related parameters of the technique such as summarizes the map tile process slicing and related parameters of the rules map tile technique, namely the scope of geographical space, scale, the zoom level,resolution maps, map tile size and format in detail.The paper proposes a new method of map tile projection. When map scale, tile size and format are settled, the geographic area displayed in the rectangular area is sliced. Next calculate the row number and column number of the geographic space the client asked for,and then download the tiles to local client to complete drawing and display of map. For the multi scale map tile file, on basis of the operating system file storage optimal number, the paper presents a fast retrieval of organization directory storage model, which balances the number of all levels of the directory map tiles. The paper also analyzes the advantages of map tiles’ storage in the file system storage.The paper studies the interface specification of RESTful realization form of OGC Web Map Tile Service and applied it into urban underground pipe network system. In the distributed network environment, the arrangement and process of map tile technology are analyzed and studied, and the pre-fetching technology of map tiles based on the interval time is proposed. Making use of the time interval of operation, download the map to the local client in advance and increase the response speed.Finally, based on the theory and technology research above, the urban underground pipe network system and the map tool is realized. Realizes the management of the system, mapbrowsing, intergrated query, summarization of data, location identification in map, controls of layers, spatial analysis, thematic map production and other functions related. These functions have made it quiet convenient for the spatial data to be storage to the Geodatabase and browsing as well as outputting it. It is proved by the practical application that the urban underground pipe network system which uses the map tile technology brings a better experience to users.