Study On Qualitative Reasoning Base On Distance And Direction

Qualitative Spatial Reasoning analyzes and processes the human cognition of geometric spatial common knowledge, it is generated by combining qualitative reasoning and spatial reasoning. It includes fields such as recognition of optic objects, routes programming, map cognition, simulation of human parable and so on. Research of Directional Relation and Distance Relation is an important part of the theory about Spatial Relation, and it is also the important base of design spatial database. Integrate these two factors will do much good to design spatial query and data process. It is greatly significative both in scholarship and practicality to digitalize city planning, construction, management and services, and to accelerate the development of GIS. The main contents and productions of this Dissertation are as follows:Firstly, this thesis introduced the concepts, methods, contents and recent study of Qualitative Spatial Reasoning and Spatial Relation.Secondly, this thesis introduced the denotative model which integrates two factors: distance and direction. There are two important models, one is based on external reference frame, which divides direction into cones and distance into segments, the other is the Qualitative Trigonometry. Then, these two methods are compared and analyzed by using them to resolve the same problem.Thirdly, this thesis focuses on Qualitative Trigonometry Reasoning. Above all, the qualitative values of angle and distance are defined reasonably. Then Qualitative Add is studied, Qualitative Subtract is presented, and the rules of reasoning are given too. Furthermore, some useful conclusions are drawn by analyzing how to select reasoning routes. After that, a formula is given for estimating how many conditions at least we must know before qualitative reasoning.Finally, based on the research work above, we developed a prototype system, which realized the modules such as Qualitative Trigonometry Reasoning, and validate the validity and feasibility of this method.The researches in this paper enrich and expand the theories for representation and reasoning of qualitative direction relation and distance relation. These researches provide the proceeding capability, validity and feasibility of Qualitative Trigonometry, and the range of using this method are expanded too.