Research On The Updating Of Vector Data For The Urban Fundamental Geographic Information System

In order to enhance the level of the urban construction and the management, more and more cities have gradually invested massive manpower, physical resource, financial resource and technical force to construct the urban fundamental geographic information system. However, the fundamental geographic database is the foundation for constructing the fundamental geographic information system. After the construction of the urban fundamental geographic database, we must do dynamic maintenance and updating to it to guarantee the updating of the data. According to the present situation of our country, it has many problems in the updating of fundamental geographic data, and the updating of the data is not easy to be guaranteed. 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 data in the fundamental geographic database, and this method is confirmed with an exact example.The main research works are as follows:(1) It analyzes the main several kinds of spatiotemporal data model at present and their different trait. The urban fundamental geographic spatiotemporal database is designed by using the relational spatiotemporal data model, and the design includes logical design and physical design of the spatiotemporal database.(2) According to different characteristic of tense, the fundamental geographic database can be divided into three databases and they are the actual database, the historical database and the temporary database. The relationship among the three databases is analyzed in detail in this paper.(3) On the foundation of summarizing the data updating methods that already exist, the implementation of data updating that based on map scale is studied. This method is suitable for the updating of vector data in the urban fundamental geographic database. With the example of the fundamental geographic information system of Lishui City, we update the vector data in the database.(4) It studies how to save the historical data when updating the data. The historical information table records the relation between the historical data and the actual data. According to the relation, the realization method of historical data backdating is studied.