基于描述逻辑规则的语义Web服务组合

摘要

针对OWL-S语义Web服务自动组合问题,提出了一种基于描述逻辑(DL)规则的建模和组合方法.将ServiceProfile中的原子服务及其输入、输出参数分别建模DL中角色和概念,将概念间上下位关系和ProcessProfile中组合流程模型建模为DL规则,以一种统一的方式刻画语义Web服务的静态功能语义和动态交互特征;提出了刻画顺序服务组合的DL规则链和描述Split+Join结构的服务组(WSC)模型,将并发服务组合转为基于WSC的顺序组合,将语义Web服务组合归结为WSC和DL规则链发现过程.与已有的方法相比,该方法将语义Web服务组合问题统一在DL规则的框架下,弥补了基于DL无法描述Web服务动态特征的缺陷,避免了Petri网推理和谓词演算等进行Web服务组合时限于命题逻辑层面无法充分利用语义信息的问题,也克服了基于智能规划的组合方法限于顺序组合的问题.%This paper introduces one kind of semantic Web service composition method based on description logic (DL) rules.Firstly, this method uses DL concepts and roles to describe the input,output, precondition and post-condition characters of atomic service in OWL-S, and adopts DL rules to figure out the hyponymy relation between concepts of domain ontology.Secondly, it defines R1,R2 and R3 DL rules to describe DL rule can describe the dynamic characters of semantic Web service,such as sequence, split and join composition process in the process model of OWL-S respectively.Thirdly, it introduces DL rule chain to figure out sequential service composition and proposes Web service community (WSC) model that can convert parallel service composition to sequential service composition based on WSC chain.Furthermore, a WSC discovery algorithm based on eliminating R2 and R3 rule can discover the composition result for one given WSR.Furthermore, the analysis and comparison indicate the superiority of this method in theory: it builds the direct semantic link between static, dynamic characters of service and domain ontology, besides it provides one kind of reasonable solution for sequential and parallel service composition in the framework of semantic Web.Finally,the simulation experiments show that WSC search algorithm can find the expected results automatically and efficiently.