Research and application of geological hazard domain ontology

Isomerous geological hazard data have four types: structural isomer, syntax isomer, system isomer and semantic isomer. Interoperability of semantic heterogenous data is a difficult issue due to its complexity and implication. Ontology not only describes exactly the meaning of concepts but also inner relationship of the concepts. So ontology can efficiently express common knowledge of specific domain by logic reasoning to get the implied relationship among concepts. Ontology is quite suitable to construct general semantic model for semantic data integration. There are three layers of geological hazard ontology: top-level ontology, domain ontology and application ontology which are used to build semantic integration and share model and differ from traditional data dictionary and metadata method. So the domain ontology plays the key role of link between top-level ontology and application ontology. Seven-step method is introduced to establish geo-hazard domain ontology. On the basis of related standards such as industry professional standard, geological hazard information processing standard and expert knowledge, geo-hazard domain ontology can be set up. Protégé 3.4.4 is developed by Stanford University is used in the establishment, management and inquiry access of the ontology with formalized representation by using OWL. Based on the abundant geological hazard data of Three Gorges Area in China, geological hazard ontology is applied to realize data and application integration and resolve the problem of decision making when single hazard or group hazards occur. Ontology is used to carry out semantic sharing model to improve interoperability capacity of geological hazard information system.