Spatial Data Orgnization Of Multi-scale Linear Objects Based On Features

Geographic Information System (GIS) is an information system specializing in collecting, storing, managing, analyzing, and representing spatial data. With the development of ongoing GIS, there are more focuses on the multi-scale and multi-view visualization, spatial analysis with the help of the known data, and the functions of graphical display, spatial analysis et. al, are must be finished by the use of the data query.Aiming at the management and query of linear features, this paper analyzed their characteristics and application requirement, discussed their spatial data model and organization, and put forward management method of multi-scale linear features.The author analyzed the problems of modeling and managing of linear features which including: multi-scale linear features spatial data model, multi-scale linear features spatial data management and consistent maintenance between multi-scale databases. In order to deal with these key problems, the author compared current data models and management methods, brought forward a model to manage multi-scale linear features based on the identification of graphical elements and linear features. The main characteristic of the model is: give each graphical element and linear feature a unique identification card (EID-. FID), and a linking interface is formed between the linear features and graphical elements and related features in different scale databases by constructing relationship between FID (feature ID) and EID(graphical Element ID) and attribute tables. Found on this model, a management method based on features of multi-scale linear features was put forward and corresponding means of query, index, visualization and consistent maintenance are devised. The correctness of the method was tested at the last part of the paper.The method proposed in the paper has been applied in real GIS system. It is proved that this method can satisfy management, query, visualization and consistent maintenance of linear features in multi-scale spatial database, and can be applied extensively in real work. The form of linking interface between the linear features and graphical elements by constructing relationship between FID (feature ID) and EID(graphical Element ID) can break the limitation of map sheet, and is convenient to query and browse linear features seamlessly for users.