Research in Database Foundations and Logic Programming at anUndergraduate Institution

这项研究涉及三个重要主题， 知识库的基础：视图更新，组合知识 不一致的知识库。算法的开发 以提供该主题中的若干问题的解决方案。认为 更新问题涉及的是 用户请求将特定视图更新为 潜在的关系。以前的算法 为分层析取数据库开发的，通过使用 专门的数据结构，并扩展到更一般的类型， 知识基础许多不同但相关的知识库 近年来建造的。以前的研究结合 知识库主要考虑确定演绎的情况 数据库。这些算法被扩展到更一般的类型， 知识库使用稳定和良好的基础语义。 有时知识库可能变得不一致。几 之前已经提出了不同的语义来定义 这些知识库的意义，以便本地化 前后矛盾产生算法来计算以下问题的答案： 使用定理证明技术在这些语义下进行查询。的 研究将有助于发展先进的知识 它还将改善研究环境， 陶森州立大学，本科院校。

This research addresses three important topics dealing with the foundations of knowledge bases: view updates, combining knowledge bases, and inconsistent knowledge bases. Algorithms are developed to provide solutions to several problems in this subject. The view update problem is concerned with the appropriate translation of the user's request to update a particular view into an update of the underlying relations. Algorithms that have previously been developed for stratified disjunctive databases are refined by using specialized data structures and extended to more general types of knowledge bases. Many different but related knowledge bases have been constructed in recent years. Previous research on combining knowledge bases considered primarily the case of definite deductive databases. Those algorithms are extended to more general types of knowledge bases using the stable and well-founded semantics. Sometimes a knowledge base may become inconsistent. Several different semantics have previously been proposed to define the meaning of such knowledge bases in order to localize inconsistencies. Algorithms are produced to compute answers to queries under these semantics using theorem-proving techniques. The research will be useful for the development of advanced knowledge based systems; it will also enhance the research environment at Towson State University, an undergraduate institution.