Dissertation > Culture, science,education, sports > Science,scientific research > Information science, intelligence > Information Science

Research of the Domain Knowledge Modeling Based on Ontology

Author SuYaPing
Tutor XuBaoXiang
School Jilin University
Course Information Science
Keywords ontology domain knowledge knowledge modeling
CLC G350
Type Master's thesis
Year 2007
Downloads 849
Quotes 12
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Recently, as the increasing popularity of the computer and Internet using, the paradox of "data rich and the poor knowledge" has become more and more serious. Different areas of people are expecting to fetch knowledge from these mountains of data and information. It is the age of knowledge economy, knowledge is an important measuring term of an organization’s core competitive ability, the capability of knowledge creation and application mainly support the core competitive ability of the Organization. Faced with plenty of information , there are some problems to solve, such as how to describe the knowledge and how to organize the information , which is an important issue of knowledge management .Therefore , in order to improve the service to infotmation users , the only way is to organize and manage knowledge effectively , which is benefit for knowledge sharing and reusing . The quanlity of knowledge model effect the performance of knowledge processing and application . There are many theories and methods about knowledge modeling . However, in practice, different developers use different knowledge representation, different development tool and application platform to construct knowledge modeling, which has restricted the communication,sharing and resusing of knowledge . When solving the new problems, we cannot reuse the existing knowledge model, and have to and continually re-design, wasting lots of resources such as human ,money and material resources.Ontology originated in philosophy. Aristotle defined "Ontology" as the science about "being" in the world. Since 1990s, ontology has been introduced in Artificial Intelligence,Knowledge Engineering and Library & Information sciences. And then the definition of ontology has been changed. Although in information science there is no general agreed definition for the ontoloty, in this essay, a well-accepted and extensively incited definition is still selected to describe what is ontology: Ontology is an explicit standardized formalized specification of a shared conceptualization. Ontology contains five components as category, slot, relation, axiom and instances respectively. category, slot and relation are essential, the other two are alternative according to different using levels.Because of the good hierarchical concept structure and logic support, ontology can support knowledge sharing and reuse. Construction of a knowledge representation model that can show more specific knowledge and the relationship between concepts. Thus to achieve the standardization of domain knowledge and helpful for knowledge sharing and reusing, and ontology is a very effective method . This paper mainly researched on the domain knowledge modeling based on ontology , how to use the theories and methods of knowledge modeling to implement knowledge sharing and reuse.Knowledge Modeling is the abstract model of the real world, effectively organizing knowledge is an important safeguard of knowledge using. Firstly, introduced several ontology-based knowledge representation language, which can be divided into two categories, the language based on the framework and logic-based language. As accurate expression ability to support reasoning function ,logic-based language became the main representation language. And then, the language based on description logic has become the main ontology representation language . OWL,which W3C recommended ,the language contains there different level sublanguage, and they are function-increasing languages. In actual use, people can use different types of language according to the type of domain knowledge.To construct knowledge modeling of a new field, we can now choose the relatively mature language OWL, It supports the conversion between several languages. To reuse the exsting domain ontology, as they use different methods and different Ontology language of different levels, we must first integrate the existing ontology. Then the essay summarize the methods of Integrating Ontology, and elaborates the domain knowledge modeling integrating process based on ontology.After selecting appropriate representation language, then began knowledge modeling, it is necessary to have a certain methodology for guidance. In practice, the foreigners researched the field much earlier than our domesic researchers. There exist mainly seven kinds of methods to build an ontology, this essay anlyse these different methods ,which are experiences from specific project. Some researchers proposed the thought of“ontology engineering”and there are many fellowers agreed with the opinion, but lack of specific methodology that mainly agreed to.Similar with Software Engineering ,the ontology is not static, as changes the sharing comcept model changes, domain changes , modeling method changes and other factors, the actual process of modeling the need to take into account these factors. This paper referenced mature software engineering methodology, applied "iterative" approach to the knowledge ontology modeling process. The important content is the "using iterative method to construct knowledge modeling based on ontology modeling" ,which stressed the process of ontology modeling is an iterative cycle of incremental process,and the ontology need to keep doing ontology evaluation and improvement.The final part is an example of an academic journal articles-reference knowledge Union ,to integrate extending the Chinese foreign periodicals and foreign journals resources ,to achieve the goal of periodical knowledge sharing and reuse. In this part, the paper used the mentioned the modeling method ,the supporting tool protégés 3.1 and the knowledge representation language OWL to construct the mini domain ontology. Because of the limited time, the modeling process may have to consider not comprehensive, inadequate follow-up study at work will be further improved.

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