基于描述逻辑的带属性依赖时序ER模型

Description-Logic-Based Temporal ER Model with Attribute Dependencies

分析了描述逻辑在数据库中的研究现状和存在的问题,特别是描述逻辑与时序ER模型的关系,在Artale的基础上提出了一种形式化带属性依赖时序ER模型εRVTAD.针对带属性依赖时序ER模型εRVTAD的需求和特点,提出了一种新的描述逻辑,即时序描述逻辑ALCQI(D)US.给出了ALCQI(D)US的语法和语义,提出了基于ALCQI(D)US的带属性依赖时序ER模型,即给出了如何将带属性依赖时序ER模型εRVTAD转化为ALCQI(D)US知识库,以及利用ALCQI(D)US的推理机制给出了带属性依赖时序ER模型εRVTAD的可满足性、冗余性、包含关系和蕴含关系等自动推理问题,证明了这些推理问题的正确性.

ER model with attribute dependencies may be translated into description logic ALCQI（D） knowledge bases,and the reasoning on ER model with attribute dependencies may be reduced to model reasoning on ALCQI（D） knowledge bases.The current research progresses and the existing problems of description logic for data bases,especially the relationship between the description logic and the temporal ER model,are analyzed.The formal definition of the temporal ER model with attribute dependencies εRVTAD is presented based on the work of Artale.Aiming at the characteristics and requirement of the temporal ER model with attribute dependencies εRVTAD,a kind of new description logic,i.e.,the temporal description logic ALCQI（D）US,is presented.The temporal description logic ALCQI（D）US is the temporal extension of description logic ALCQI（D） through temporal logic,and the syntax and semantics of ALCQI（D）US are given.The ALCQI（D）US-based temporal ER model with attribute dependencies is presented,how to translate temporal ER model with attribute dependencies εRVTAD into temporal description logic ALCQI（D）US knowledge bases is studied,and the reasoning problem of satisfiability,redundancy,subsumption relationship,and implication relationship of temporal ER model with attribute dependencies εRVTAD may reason automatically through reasoning mechanism of temporal description logic ALCQI（D）US,and the correctness of these reasoning problems is proved.