Change Detecting And Updating Of Objects From Maps Of Different Scales

Abstract:Currency is a leading indicator to measure the quality of spatial data. In order to keep the currency of spatial data, spatial database need to be updated continuously. Under different access and user requirements, the current spatial database contains a variety of scale map data. Therefore, among the current multi-source data, dimension problems are common problems existing in the objective world. On the ground of study on the existed changing detection and updating method, by taking the data scale into consideration, changes in classification, detection and update process are analyzed, and objects’changes detection and updating method from maps of different scales is designed in this thesis. The specific research content are as follows.(1) Based on the summary of changes of the common data category including point, line and face, changes of typical data categories are analyzed and described by considering the influence of geographical events. For examples, typical residential objects and hydrographic objects are chosen to analyze the changing categories.(2) Changes detection of objects from maps of different scales is one of the hottest spots of current research. Using larger scale maps with strong currency to discover and detect changes is very efficient and costs little. Therefore, taking smaller scale map with weak currency for reference, changes of objects from maps of different scales is detected by using special decision rule, then typical data is used for experimental verification.(3) Aimed at the changes detection in this thesis, a set of changes updating method is designed. Finally, the method is verified by typical data, which indicates its feasibility.(4) On the basis of general principles for system development, by using C#and ArcEngine9.3changes detection and updating system of objects from maps of different scales is realized, and the system is carried out based on typical data, which verifies its feasibility. Researches show that changes detection and updating method of objects from maps of different scales is a feasible way to detect and update changes of objects from maps of different scales.