The Study On Thesaurus-based Construction Of Domain Ontology

As we all know, the thesaurus is a kind of artificial language which is made to organize information. The essence of the thesaurus is choosing, specificating and expressing human language in order to make a controlled dictionary. The thesaurus is made to retrieve information from the large number of document conveniently. However, WWW contains a huge number of information and the information is growing exponentially. As the growth of the information, the huge number of nonstructural and half-structured digital information makes it more and more difficult for people to find the needed resources. It has become an important and urgent issue for the researchers to reconsider how to organize the huge digital information, which cause the controversy on the adaptability of the traditional knowledge organization instruments (for example, the thesaurus, taxonomic table) in the environment of Internet. Although the traditional knowledge organization instruments are developing over the time, their interoperability and semantic expressive power is a problem to the machine language.In order to solve this problem, people come up with a concept modeling tool-Ontology, which would describe information at the level of semantic and knowledge.The importance of constructing domain ontology is:First, the aim of constructing domain ontology is to acquire knowledge of this domain, and to define the admissive concepts and the relationship of these concepts at different level in a formulized mode. As a result, a criterion of understanding knowledge is developed. So, domain ontology offers a top-level concept framework of people's cognition.Second, ontology emphasizes the function of knowledge sharing. Although both of the thesaurus and ontology expresses the relationship of the domain concepts, the ontology stresses on providing a framework of the domain knowledge. Because the concept of ontology has its own attributes and instances which are not demonstrated in the thesaurus, the ontology are usually called a collection of domain knowledge.Third, ontology provides a machine language, which can be understood by computer. We can get over the problem of semantic gap from different kinds of computer systems. As a result, the conversation, mutual-operation and knowledge sharing of different entity can be realized. The ontology is considered as an explicit specification of the formulized conceptualization. The formal means the ontology can be read by the computers.It is the trend to use the ontology in the Internet environment. And it is to be argued that whether we should get rid of the thesaurus or get use of it. The author chooses the latter one. Because of the similarity and the differences of the thesaurus and the ontology, it has advantages to construct ontology on the basis of the thesaurus. As the thesaurus contain nearly all terminology in the field, which can provide some clues to creating concepts in the ontology. What's more, the narrow term, border term and related term are also useful in creating the attributes and instances of the concepts...