DeepWeb中的海量信息只能通过查询接口访问获得,为了能够同时访问同一领域多个Web数据库,需要对多个Web数据库的查询接口进行集成.因此,引入本体技术,提出基于本体的DeepWeb查询接1:2集成方法.DeepWeb查询接口集成主要完成两个方面的工作:模式匹配与模式融合.模式匹配采用本体的“Bridge(桥接)”效应建立不同接口模式间的属性映射关系,以准确发现不同接口属性间的语义关联.模式融合根据模式匹配的结果,合并DeepWeb数据库查询接口集合中表示同一语义的属性,并尽可能地保持该领域查询接口的结构特征和属性顺序,以获得集成查询接口.通过实验分析,基于本体的DeepWeb查询接口集成方法不仅简化了模式匹配的复杂过程,而且很大程度上提高了模式集成的精度.因此,基于本体的DeepWeb查询接口集成方法是高效可行的.
A significant amount of information in Deep Web can only be accessed through the query interface of a back-end database, instead of traversing static URL links. In order to access domain- specific databases simultaneously, it is important to construct an integration interface which allows uniform access to disparate relevant sources. Therefore, a novel method of interface integration based on ontology technique is proposed in this paper. It mainly subsumes two aspects: schema matching and schema merging. Schema matching is used to accurately identify the semantic correspondences among the attributes from different interfaces by exploiting the "bridge" effect of ontology, which can match many schemas and find all mapping relationships at one time. Schema merging is used to merge the source query interfaces to construct a unified schema based on the identified mapping relationships after schema matching, which should encompass all unique attributes features and sequences over the given set of interfaces as much as possible. Through a detailed experimental evaluation, it is indicated that the approach of interface integration based on ontology not only reduce the complexity of schema matching instead of finding pairwise-attribute correspondence in isolation, but also greatly improve the integration accuracy of interfaces. Therefore, the ontology-assisted interface integration approach is feasible and effective.