关键词: 地理信息系统, 方向关系, 模糊描述, 自适应采样

Abstract: Due to the vagueness of spatial directional relationship, we discussed the basic essential characteristics of fuzzy directional membership functions and established the reference framework of 8-directions fuzzy description based on nonlinear functions, which is integrated with fuzzy theory and existing experimental results. Then, by analyzing the influence of factors of directional relationship such as the distances between objects, and the shapes and sizes of objects, an adaptive sampling model is presented, which can transform the directional relationship of spatial object into the sampling point sets. Therefore, 8 directional fuzzy matrixes are obtained with this model to do a quantitative calculation. Through the statistics of these fuzzy matrixes, the detailed fuzzy description of directional relationship is achieved. At last, a concrete instance and the result of experiment show that not only the appropriate sampling granularities were chosen automatically, but also the detailed fuzzy description of directional relationship between arbitrary spatial objects can be achieved effectively using this model.

Key words: gis, direction relations, fuzzy description, adaptive sampling