Study on Ontology Model Based on Rough Set

Now ontology has been widely used by Artificial Intelligence as an explicit specification of conceptualization in various areas, such as conceptual modeling, information integration, agent-based system design, and semantic web. In this paper, we introduce rough set theory to Ontology. It extends the uncertainty representation in domain ontology and supports uncertainty reasoning. It is more flexible in handling imperfect ontology concepts and relationship between those ontology concepts. We introduce the concepts of the upper approximation, the lower approximation and certainty to ontology based on rough set theory. It can process the problem of ontology attribute significance and attribute reduction in ontology construction and so on. An example of ontology attribute significance shows the feasibility of this method.