Research On The Key Techniques Of Multi-dimensional Navigation Application Platform

Recently, the development of relevant theories and technologies of digital earth, continuously appeared multi-dimensional GIS (Geographic Information System) and relevant SDK, make it an inevitable trend for GIS to be large-scale and multi-dimensional. The rapid development of relevant technologies of cloud computing and service publication, the release of Geographic information-Web Map Server Interface, one of the national standards of P.R.C in 2005 and OpenGIS Web Map Tile Service Implementation Standard released by OGC in 2010, make service publication a main trend to use the geographic data. Therefore, the future trend of GIS is large-scale, multi-dimensional and services. CHANGJIANG RIVER ADMINISTRATION OF NAVIGATIONAL AFFAIRS proposed the idea to establish a "digital Yangtze", which not only reflects the demands of Yangtze River shipping informatization and intellectualization, but also reflects the urgent application demands of large-scale, multi-dimensional and service GIS in the shipping industry.First, summarize the development status of the Web Map Service and the previous application research results on digital earth geographic model. Then, analyze the problems of the application research on digital earth geographic model in the shipping field. Last, give the relevant technologies and algorithms.Followings are the major work of this paper:(1) Continue to research on the navigation application based on the stand-alone multi-dimensional platform which established by the predecessors of our laboratory. In this thesis, we analyze the projection transformation of Remote sensing satellite image to make sure that the fusion of terrestrial image data and chart data is in the same projection coordinate system and solved the error problem caused by fusion of different projection drawings, and improved the accuracy of the data fusion.(2) Make a mercator projection transformation for the grid points based on the spherical model to transform the spherical global model to the mercator projection plan model. This can make the multi-dimensional platform be applied to chart work and other navigation applications, to meet our navigation habit.(3) Analyze and study on the organization of server-side data, and the publication technologies, and client operating modes and the relevant technologies, design and implement a prefetch algorithms of tiles for client based on the existing platform.