中文摘要：

在信息过滤系统中,用户模板是机器可理解的用户需求表示形式,是否能准确地反映出用户的真实需求将直接影响着过滤系统的性能.在向量空间模型中,用户的模板表现为一组带权重的特征词集,但由于在这样的用户模板中缺少必要的语义信息,很难准确地反映出用户的需求.本文提出了以本体构造需求模板的方法,以本体的形式定义需求中概念间的语义关联关系,将向量空间模型中的特征向量定义为本体中的实例,通过实例间的关联路径计算特征项间的语义关联,并通过特征项间的语义关联计算出文档与模板的语义关联度.

英文摘要：

In the task of information filtering, the profile of the user＇ s interests and preferences is the key to the performance of the system. In the vector space model, the profile is usually represented as a set of features, but this kind of profile can not exactly reftect the user＇ s information requirements for the lack of the semantic information. This paper proposes an approach to construct the user＇ s profile based on ontology. In our method, the features in the vector space model are defined as the instances in the ontology, and their semantic relations are represented by the means of concept-properties model. We also designed a method to compute the semantic association between the instances according to the length of their paths in the ontology graph, furthermore, the semantic relation between the document and the profile is calculated through the semantic association between the features.