Research On Qualitative Spatial Reasoning In Description Logic

Qualitative spatial reasoning combines qualitative reasoning, spatial reasoning and artificial intelligence together. It has become a hot topic in the research of artificial intelligence. Qualitative spatial reasoning researches the expressing and processing of human cognition of geometry spatial objects and their relations. As an important component of spatial relations, spatial topology relations research the constant properties of space objects with topological transformation. The expressing and reasoning of spatial topology relationship is very important because it is the basis for the establishment of qualitative spatial relations.At present, the research of spatial topology relationship has made great progress, but using first-order logic without any additional constraints, will result in many problems such as destroying the structure characteristics of the knowledge and inconvenient for reasoning, and so on. On the other hand, the first-order logic is too strong to handle determined and effective issues. The description logic proposed in 1980s is a decidable subset of first-order logic, and it can give decidable reasoning service. Therefore, the description logic has been paid special attention and been used in more and more fields as the knowledge representation tool. But, qualitative spatial reasoning is still a new field for the research of the description logic.This thesis fully uses the expressing and reasoning ability of description logic and applies it in the spatial reasoning to increase the accuracy and decidability of the reasoning. The main work is listed as following:Firstly, this thesis put forward the qualitative spatial concrete domain.This thesis has analyzed existed spatial topology expressing methods, and then gives the qualitative spatial concrete domain which based on the description logic and contains the set of basic spatial objects and the topological relationships between them. On this basis, the thesis put forward the symbolic expressing of the topological relationships which are in the concrete domain and use description logic to express the spatial relationships.Secondly, this thesis gives the reasoning rules of spatial topological relationship which based on description logic.This thesis put forward the reasoning rules of spatial topological relationships which based on description logic and then introduce it through an example.Thirdly, this thesis put forward the qualitative spatial relationships satisfiability determination algorithm.This thesis has researched the appropriate formal language which can be used in qualitative spatial reasoning, and then put forward the qualitative spatial relationships satisfiabiligy determination algorithm and illustrates the application of this algorithm through an example.Fourthly, this thesis put forward the example of the application of qualitative spatial reasoning which based on description logic.This thesis put forward the synthesized application of reasoning rules of spatial topological relationships and satisfiability determination algorithm and consistency detecting through the example. It gives the preliminary exploration of how to apply the description logic to the qualitative spatial reasoning.