Research On Representation Of Fuzzy Spatio-temporal Knowledge With Ontology And Construction Method Based On Petri Net

In the real world, time and space are closely linked. In the cognitive process of spatio-temporal knowledge, human beings come to realize the importance of spatio-temporal model. At the same time, some data in spatio-temporal knowledge are of fuzziness due to human subjective understanding of objective world. With the development of ontology languages in the Semantic Web, web ontology languages came into being successively. However, these ontology languages cannot express fuzzy spatio-temporal knowledge existing in Semantic Web. Consequently, the fuzzy spatio-temporal ontology is proposed in order to express the fuzzy spatio-temporal knowledge in Semantic Web. Based on this ontology, this thesis studies the construction method which maps fuzzy spatio-temporal Petri net into fuzzy spatio-temporal ontology.For the fuzzy spatio-temporal information in the real world, the basic framework of fuzzy spatio-temporal ontology is presented in this thesis. Then, the formal definitions of fuzzy spatio-temporal top-level concept ontology, fuzzy spatio-temporal object ontology and fuzzy linguistic variable ontology are given. In addition, on the basis of fuzzy description logic, a proposing logic named the fuzzy spatio-temporal description logic (FST DL) is available, which provides the logic foundation of FST DL to fuzzy spatio-temporal ontology. Meanwhile, the syntax and semantic of FST DL, and the definition of knowledge base are given as well.Based on FST DL, this thesis presents the Fuzzy Spatio-temporal Web Ontology Language (FST OWL), which gives the fuzzy spatio-temporal ontology an ability to express language. Moreover, the representation ability of the language is introduced in detail from the two aspects of class description and axiom of FST OWL. And the data type of FST OWL is extended on the basis of OWL.By studying the relationship between fuzzy spatio-temporal Petri net and fuzzy spatio-temporal ontology, a method of construction is investigated to translate fuzzy spatio-temporal Petri net to fuzzy spatio-temporal ontology. Furthermore, the transformation algorithm is presented to enable sharing the fuzzy spatio-temporal Petri net on Semantic Web. Of course, the correctness of translation is also proved.