Multi-granularities approximate method for obtaining qualitative spatial relations

Qualitative spatial relations are widely used in spatial description logics, spatial ontologies and other applications. Efficient method to obtain qualitative spatial relations from traditional GIS has not been discussed in previous literatures. We give an efficient method for calculating qualitative spatial relations. We propose the multi-granularities approximate representation of GIS objects which requires less process time. Then some algorithms are proposed to calculate the spatial relations based on multi-granularities approximate region. The analysis and test result all show that our method supports complex and integrated spatial relations and require less process time than traditional spatial query.