The Model Of Spatial Relationship And Application In Spatial Query

The representative model of spatial relationship is the basis of spatial analysis. It decides how to abstract, store, process, analyze and output the relationship among spatial entities, It is also very important for modeling spatial data, spatial query, spatial analysis and spatial consequence. As a qualitative representation for spatial relationship it is close to the spatial relationship used in everyday life. Since this is easy to understand, it is used widely in spatial analysis.On the other hand, spatial query is an important function of th e application system of GIS. With the development of intelligent GIS systems, the simple query function provided by the traditional GIS software cannot meet the new demands of spatial query. Therefore, developers have to append the spatial query function on the base of the query function provided by the platform software of GIS. The combined query is one of the most important new query demands. In addition, the traditional way to realize it is to find a kind of spatial model to represent the direction relations and the topological relations simultaneously. Due to the limit of the complexity of the spatial relation model, realizing the combined query has become a problem.This thesis found a spatial relationship models' capability in displaying direction relations is not equal to its capability in displaying topological relations. A model which is good at displaying the direction relations is not always good at representing the topological relations. Using a model to deal with both of them, a complicated mechanism has to be created to overcome this difference. On the other side, the precision demand of different users is unequal. A uniformed model cannot meet this difference. The combined model introduced by this thesis can select the most appropriate direction relations model and topological relations model based on the requirement of users. And developers can realize the combined query function without being familiar with the complicated mechanism.This thesis systemically analyzes the difference in qualitative spatial relations models. Based on the theory, this thesis selected 4-intersection models for spatial topological relations and symbolic spatial index modeling for direction to describe the use of combined models. A spatial query prototype system was built in order to prove the combined model can be used to realize the representation and application of combined spatial relations. This system includes the following modules: the module of basic function, the module of direction relation query, the module of topological query and the module of combined query.