Ontology Construction And Knowledge Retrieval Model Research

The information and document in enterprise or libraries has increased explosively with the development of economy. The increasing number of information resources changes the level of people's information demand in modern society. The developing level gives retrieval technology a great challenge, thus new ideas and methods are introduced into the field of information management to reform its theory and technology. So comes one of the hot topic-Ontology and ontology-based knowledge retrieval (KR), which is discussed in this paper.An ontology is an explicit specification of a conceptualization. In principle, ontologies are sets of concepts and relations which reflect context and binds of concepts.Ontologies perform well as an advanced technology of knowledge representation in Artificial Intelligence (AI). Through the ontological theory and technology, system can transform dominant or recessive knowledge easily distinguish by the computer, and performs to infer, greatly enhances accuracy ratio of retrieval information, make knowledge management more effective and higher quality. This paper discusses ontology building and ontology-based Knowledge retrieval model.The author intensively investigates and surveys large number of documents and web resources (ex. text paper and software tools).The theory and technology of ontology have been described, including origin, definition, type, popular ontologies knowledge base and knowledge retrieval procedure. Furthermore, the paper in detail introduces the elements and process of ontology-based knowledge representation, namely using the elements of representation to formalize knowledge. Specially, for demonstrate the procedure, taking a simple example of knowledge representation, the author selects the knowledge of machining processing technology as the field, and extracts the domain's concepts, establishes the set and relations among them, thus constructs its ontology-based concepts set. At the same time, the theory of ontologies building has been introduced, including the general principle, several methods, ontological language and tools. The comparisons have made among 4 methods of building ontology, 12 ontology specification language, and 4 tools for editing ontology.The paper discusses the model, strategy and methods of ontology-based KR system. In some respect, the author explained the different views, makes some change and optimizes the model.On the basis, the paper introduces a domestic system prototype-Kretrieval.Nowadays, western researcher has developed some successful knowledge retrieval system, such as Onto-Feb and Onto-Knowledge. In comparison, study on this at home is just starting. The relevant knowledge about ontology for the retrieval is the lack of research, but our researcher is making much progress on this. "Kretrieval" is one success."Kretrieval" is a National Natural Science Foundation-funded projects, and one of prototype experimental system of Education major in humanities and socialscience research projects-"IVAKR(Information Visualization and KnowledgeRetrieval )".The author explains "Kretrieval" knowledge acquisition, organization principle and implement method, then evaluates the model.With high application value, ontology-based KR system will be rapidly introduced into modern library and intelligence science as the tendency.