Landmark-based qualitative reference system

It becomes more and more important for next generation of GIS to develop cognition-accordant data models which is properly guided by the way how human actually thinks about geographic space. Thus, a new method named landmark-based qualitative reference (LBQR) system is introduced to express qualitative positional information in this paper. Qualitative position can be determined by one or several landmarks which are calculated adaptively according to the target object under LBQR framework. In LBQR framework, qualitative coordinates (QC) are used to represent the position of the target object. QC is defined based on cardinal direction relations between target object and one or several landmarks adjacent to it. At first, Voronoi model is used to determine the reference objects for each target object. Then cardinal direction relations are modeled by minimal bounding rectangle method or cone-based method according to the geometry type of each reference object respectively. Last, an experiment is carried out to evaluate whether the Voronoi model conforms to human spatial cognition.