The Method of Urban Fundamental GIS Data Updating

摘要

A necessary updating degree is vital for the urban foundational map data in a geographical information system. Only when the digital map data are well updated, can the quality of the GIS application be assured. Today the companies devoting to the production of electronic topographical data for urban construction and management have to cost much labor, material and capital to collect and update data in order to maintain a suitable updating degree. Ordinarily the updating frequency of the mother database in the server is one or half of a year. This is the main reason why urban GIS, which seems such a fantastic tool, doesn't work in real application and it is also a realistic problem confronted in the development of urban GIS. In view of the problems that the techniques and methods are simple and fall behind, furthermore we lack efficient data updated system and methods and so on; this paper focuses on the data updating model and method. According to objectoriented concepts and the distribution characteristic of features and geographic phenomena, GIS features are divided into three types, point features, line features and area features, from which framework data can be extracted conveniently. This paper carry out the research based on the spatiotemporal data model, and make the design of urban fundamental geographic spatiotemporal database. This paper also puts forward an updating method that is suitable for the vector map data in the fundamental geographic database, Furthermore, we have designed and done the experiment for data updating; it has proved that the correctness from the data updating just the same with that from the manual work, which works efficiently.