Research And Implementation Of Storage Of Ontology Reasoning Mechanism In Relational Database

Semantic web is a distinctive technology comparing with the current webs thatexisted. The information is no longer simple word or picture, but labeled clear semanticin semantic web. By loading intelligent semantic program, achieving definiteinformation, it provides a new network service model to get rid of heavy searchactivities. The ontology which is the core of the semantic web can describe humanknowledge by means of classes, properties, instances and axioms. The ontology playsan important role in the hierarchical structure of semantic web, not only describingdomain knowledge, but also strong logical reasoning ability.Currently, storage of ontology was based on filesystem, but it resulted in memorycost, low accessing speed, lacking transaction mechanism and it was difficult to extend.Based on above weakness，an ontology reasoning model based on relational databasestorage model was proposed and realized. The following aspects were studied:(1) The ontology technologies, such as the definition, the application of ontologyand the describing language were analyzed. The theoretical foundation of ontologyreasoning was discussed in detail. Rule-based and description logic-based ontologyreasoning mechanisms were described.(2) The syntax of the ontology language OWL was discussed in detail from theangle of the classes, properties, and instances. Reasoning rules of ontology weresummarized from the aspect of classes and properties.(3) The relational database was used to store and realize the reasoning of ontology.Design of storage model of the ontology was based on the classification of ontologyelements. The mode of reasoning was designed based on storage model. Reasoningresults were separated to process: axiom-based reasoning results were stored into arelational database, while instances-based reasoning results were obtained in the processof querying. The querying mode was also designed and optimized to speed up thequerying efficiency.(4) An ontology reasoning system was built based on above ontology model. Thesystem should realize the function of storage, reasoning and querying of ontology.Finally, reasoning and querying results verified the effectiveness and correctness of thesystem.