Integration of Information from Internet Sources

多个互联网数据源的集成提出了许多新的挑战，如处理半结构化数据，在不完全了解源结构的情况下创建视图，适应源的有限查询接口(能力)，以及回答涉及虚拟对象的查询，这些查询是复杂信息融合操作的结果。最近的工作提供了灵活但往往效率低下的方法，以迅速发展实现上述目标的调解人。这项研究开发了数据结构、算法和系统，这些数据结构、算法和系统可以在不影响开发灵活性的情况下提高性能，通常是数量级的，并改善用户界面。建议使用数据指南来描述在每个信息源和调解人创建的综合视图中显著出现的概念(或概念的组合)。数据引导计算算法使用(1)中介器规范、(2)源数据的解析器和(3)查询结果的实际数据。调解器和用户界面被扩展以在查询处理和查询制定时使用数据指南。该研究还开发了以下算法：(1)进一步扩展调解器的能力以适应源的有限能力，(2)使用源数据的知识(例如，依赖关系)来增强对象融合查询的性能，以及(3)优化部分答案的传递。这项研究将展示如何快速开发灵活的集成系统(例如，通过集成多个Web购物网站来构建虚拟购物中心的系统，或融合与公司相关的所有可用财务信息的系统)，同时仍能实现难以构建的定制集成系统的性能。

Integration of multiple Internet sources poses many novel challenges such as handling semistructured data, creating views without complete knowledge of the source structure, adapting to the limited query interfaces (capabilities) of the sources, and answering queries referring to virtual objects which are the result of complex information fusion operations. Recent works have provided flexible, though very often inefficient, ways to rapidly develop mediators that achieve the above goals. This research develops data structures, algorithms and systems which can enhance the performance, often by orders of magnitude, and improve the user interface without compromising the development flexibility. Data guides are proposed for describing the concepts (or combinations of concepts) that significantly appear in each source and in the integrated view created by the mediator. Data guide computation algorithms use (1) the mediator specification, (2) the parser of the source data, and (3) actual data of query results. Mediators and user interfaces are extended to make use of the data guides upon query processing and query formulation. This research also develops algorithms that (1) further extend the mediator's ability to adapt to the limited capabilities of the sources, (2) use knowledge (e.g., dependencies) of the source data to enhance the performance of object fusion queries, and (3) optimize the delivery of partial answers. This research will demonstrate how flexible integration systems (such as systems for constructing virtual malls by integrating multiple Web shopping sites or systems for fusing all available financial information relating to a company) can be rapidly developed while still achieving the performance of hard-to-built custom made integration systems.