The Imprecise Ontology Modelling And Its Construction

The philosophical term Ontology was first introduced into the domain of information science when T.Gruber gave the definition "An Ontology is an explicit specification of a conceptualization" in 1993, which indicated that explicit is the essential character. Therefore, Ontology was considered as a "precise model" when it was first introduced into the domain of information science. And the proposed "seven layers of the Semantic Web architecture" was also based on "precision". However, the original goal of the Semantic Web is to create a smart and computer-understandable network, which requires it to deal with both precise and imprecise data. That is, currently being built should be an "imprecise Semantic Web". In such circumstances, the importance of building an imprecise Ontology is stand out. Without the imprecise Ontology, we can't process some work such as imprecise Ontology merging and reasoning. Similarly, without imprecise Ontology which is the base of Semantic Web, Semantic Web can do nothing and the Semantic Web service is impossible to achieve.Domestic and foreign research about imprecise Ontology has just started, and most of them stay in the phase of rough Ontology construction and fuzzy Ontology construction. They didn't integrate the rough Ontology and fuzzy Ontology to be an independent imprecise Ontology. In this paper, an imprecise Ontology model is proposed after analyzing domestic and foreign method about rough Ontology and fuzzy Ontology construction and introducing the inclusion degree theory combined with rough set and fuzzy set theory to define its relationship. Under the guidance of the proposed model, an imprecise medical Ontology is built using an Ontology building tool Protege. The process of building this Ontology reflects both rough and fuzzy character. By comparing with precise Ontology and imprecise Ontology, the built imprecise Ontology is evaluated using precise Ontology and imprecise Ontology evaluation tool. At last, the research direction of imprecise Ontology is shown.The results of this paper not only can speed up the process of imprecise Ontology building, but also can improve its scientificalness, standardability and authoritativeness. Provide an optional and effective method for imprecise Ontology building.