Research On Automatic Updating Method For Land Use Data Based On Topology And Spatial Similarity

Spatial data updating is one of the most significant ways to guarantee the data be accurate and complete. Spatial data updating method with high efficiency, high quality and sustainability is a hot research issue for domestic and overseas scholars all the time. Large amount of change data and limited task time make the annual updating of land use data become a time-consuming and labor-intensive task. Therefore, it is desirable to improve the existing data updating method which is mainly conducted by manual operation and to improve the automatic updating level for the land use database.Based on the existing spatial database updating method, the characteristics of land use data and the actual demand, the paper studies automatic spatial data updating method from the following several aspects.Firstly, geographical events detection and expression are key to realize spatial data updating automatically. The paper utilizes metric indexes of topological relation and spatial object similarity, combining with the land use data constraints of topological consistency, semantic logic and topo-semantic to detect geographical events based on change information. Besides, the paper defines’Protogenic Event’ and ’Secondary Event’ to describe the derivative relationship between two geographical events and to express the geographical events formally.Secondly, the paper puts forward a common edges evaluation model to detect the problem of common edges with misalignment based on position similarity, length similarity and direction similarity. And the method of feature points fusion is adopted to eliminate the gap between the common edges to ensure the data quality during automatic updating.Thirdly, a complete process for land use database automatic updating is presented based on the geographical events detection and the solution for common edges misalignment problem described above. From the perspectives of topological relation, spatial similarity and semantic logic consistency, the paper makes the judgment on ’Protogenic Event’ and ’Secondary Event’ based on change information and expresses the event formally. Then the corresponding updating operators are employed to realize the database automatic updating.Finally, the paper applies the automatic spatial data updating method proposed above to Land Use Data Management Information System, and makes a comparison with the results by manual operation to verify the feasibility and effectiveness of the method.