【作者】 李学庆；

【导师】 贾玉文；

【作者基本信息】 辽宁师范大学 ， 图书馆学， 2008， 硕士

【摘要】 随着网络信息的爆炸性增长,常规的基于关键词的网络信息检索技术已越来越不能满足用户的检索需求,而本体论作为一种新的知识表示方式,由于具有良好的概念层次结构和对逻辑推理的支持,因而在网络信息检索中具有广阔的应用前景。通过本体论,一方面可以把信息检索从基于关键词的层次提高到基于概念的层次,从而提高系统的查准率与查全率;另一方面可以对概念之间的相关性进行推理挖掘,从而满足用户进行智能化信息检索的需求。本文对本体论在网络信息检索中的作用,从用户需求的分析与实现、目标文档的分析与语义标引以及用户兴趣模型的构建等三个方面进行了深入的分析与探讨,并在此基础上构造了一个基于本体论的智能化网络信息检索模型。本文的主要贡献有:1、提出了一种基于本体论的网页文档的标引算法。该算法利用本体论对提取的网页特征词汇进行概念歧义的消除,然后建立本体论与网页文档之间的映射关系,从而实现对网页文档进行语义标引。2、提出了一种基于本体论的智能化查询算法。该算法充分利用本体论的推理功能,把出现在用户查询中的概念、关系以及属性等信息进行综合考虑,从而挖掘出用户的真正需求所在。3、提出了一种基于本体论的智能化网络信息检索模型。该模型的实现不仅比传统的检索系统具有更高的查全率和查准率,而且在一定程度上使检索系统更具智能化和个性化。更多还原

【Abstract】 With the rapid increment of the information on the web,Traditional information retrieval based on the keywords is far from user’s satisfaction in recall and precision. As a new way of knowledge description,ontology will have a wide prospect of application in search engine area because of its capability to represent meaning of the information by a hierarchical structure and its reasoning support.On the one hand,The information retrieval can be promoted from the keywords level to the conception level by ontology,It will promote the recall and the precision;On the other hand,The relevance of the conception can be exploited and reasoned,It will realize intelligent information retrieval. This thesis gives in-depth analysis and discussion about the function of the ontology in three aspects of information retrieval,including the analysis and construction of user’s demand、The analysis and semantic indexing of targeted documents and the construction of user interest model,And then an intelligent information retrieval model based on ontology is given.The main contributions are as follows:1.Propose an ontology-based semantic indexing method. The method takes advantage of ontology to clear the conceptual ambiguity and then build the reflective relationship between ontology and the web document,which realizes the semantic indexing of targeted document.2.Propose an ontology-based intelligent query method. The method takes full use of the function of ontology reasoning,and gives a full consideration of concepts、attribute、relationship and other information in users’query,which can find out what users really need.3.Propose and implement an ontology-based intelligent information retrieval model. The realization of this model not only will promote the recall and the precision but also makes the retrieval system more intelligent and personalized.更多还原