Construct And Realize The Model Of Spatial Data Conversion Based On Vector Data Structure

Topographic map is the most importent data source of GIS. But most of topographical map database produced by survey department is only cartographic data, which is vector data structure, but cannot be imported into GIS directly to meet GIS using. Abandoning these cartographic data entirely and digitizing map in term of GIS needing is extravagant. So it is realistically and economcially to transform cartographic data to GIS spatial database. The author investigated the actuality and trends in this respect, and concluded that there are two kinds of transform between cartographic data and GIS data, one is format conversion, the other is semantic information conversion. There are some problems in the semantic information conversion, which become the difficulties of GIS database creation. In author's opinion,conversion from cartographic data to GIS database is essentially data model conversion according to modeling analysis. So the purpose of this research is to construct and realize conversion models from cartographic data to GIS database.There are six chapters in this thesis.The first chapter of Introduction illustrate the background of the subject, purpose of this research, the actuality and trends in this respect in the world,the main content innovations of my own research. The second chapter of analysis of the characters between CDM (cartographic data mode) and GIS data model explains that the data model of the cartographic data is DCM(Digital Cartographic Model) which essentially is Mapping Model. Then the author contrast CDM and GIS data model, demonstrates differents between of them. The third chapter of designing the transform model constructs the conceptive model and logical model. The forth chapter of model realizing tells the realization of model by use of arcgis modelbuilder. The fifth chapter of using example demonstrates the using of transform model.The last chapter of conclusion summarizes of all of above and brings forward what is going to do at next step.There are some innovative respects: construct transform model instead of embodied transform technic; Using arcgis modelbuilder designs and realizes model can simply the process of modeling and improve the efficiency of processing.