A Research And Application Of Intelligent Question Answering System Based On Ontology

Question Answering (QA) is an indispensable part of teaching process. The effect of QA is largely decided by its accessibility and how well it can satisfy students' individual needs. Many scholars are committed themselves to the realization of network-based intelligent question answering system. Starting from course knowledge ontology, this paper, by using comprehensive FAQ an document database technology, aims to develop a network-based intelligent question answering system, which enjoys high match ratio and multiple enquiring methods.The contents of this paper mainly cover:1. A course knowledge ontology is established. The paper firstly establishes a course knowledge ontology in line with the course syllabus, Taking the course of LAN Technology and Application as example, based on which the range and content of course ontology FAQ database are decided, and course knowledge keywords database is obtained.2. A question understanding database is established. To assure correct understanding of users' questions, a question comprehension database is established which is composed of question signal words, question leading words, and standard question types and constructions. Within the FAQ database, knowledge keywords and question type match technology is used to answer questions, while questions outside the FAQ database will be directed to the course database and possible answer document will be obtained by document similarity match.3. A course document database is established. A course document database, the natural extension of course ontology FAQ database, is designed to answer narrative questions and thus improves the completeness of system. The search of answer documents is realized through VSM document similarity computation technology and questions from users are processed as documents. In order to improve the search speed, the system pre-processes course documents, namely picking up question type leading words or picking up course knowledge keywords by pressing TF-IDF.4. A intelligent question answering system is realized. By using .Net technology, an intelligent question answering system for the course of LAN Technology and Application is constructed. The system is characteristics of a functional combination of natural language questioning, browsing and searching. Experiments show that the method and technology introduced in this paper are effective. Good results are achieved by using the system in question answering.The major advantages of the system include:1. The FAQ performance and efficiency are greatly improved through course ontology FAQ database's accuracy, quickness and the completeness of document database technology.2. Search range and knowledge keywords are determined from course knowledge ontology, discarded the bulky but incomplete standard lexicon and words segmentation technology, basically eliminated the words segmentation process and avoided words ambiguity. The overall question answering efficiency is improved.