基于Petri网的语义Web服务自动组合方法  

A Petri Net-Based Semantic Web Service Automatic Composition Method

作　　者：汤宪飞[1] 蒋昌俊[1] 丁志军[1] 王成[1] 

机构地区：[1]同济大学计算机科学与技术系

出　　处：《软件学报》2007年第12期2991-3000,共10页Journal of Software

基　　金：Supposed by the National Natural Science Foundaion of China under Grant Nos.60534060;60473094(国家自然科学基金);the National High-Tech Research and Development Plan of China under Grant No.2007AA01Z136(国家高技术研究发展计划(863));the National Basic Research Program ofChina under Grant No.2003CB317002(国家重点基础研究发展计划(973))

摘　　要：Web服务组合使得开发人员可以快速地创建自己的应用程序.但是,随着Internet上可用的Web服务数目的增加,Web服务组合是一项高度复杂的任务.针对语义Web服务的自动组合问题,提出了一种既考虑服务输入/输出又考虑服务行为约束的自动组合方法.首先,注册服务被转化为一组Horn子句形规则,用户的输入和输出请求分别被转化为Horn子句中的事实和目标,从而将寻找满足用户输入/输出请求的合成服务问题转化为Horn子句的逻辑推理问题;然后,用Petri网来为该Horn子句集建模,T-不变量技术被用来判定是否存在满足用户输入/输出请求的合成服务;最后给出了两种算法来获取既满足用户输入/输出请求又满足用户行为约束的合成服务的Petri网模型.Web service composition allows developers to create applications rapidly. But due to the tremendous growth in the number of Web services available, the Web service composition problem is still a challenging research issue. This paper introduces an automatic Web service composition method which considers both services＇ input/output type compatibility and behavioral constraint compatibility. The services available are translated into a set of Horn clause-like rules. User＇s input and output requirements are modeled as a set of facts and a goal statement in the Horn clauses respectively. Then Petri net is chosen to model the Horn clause set and T-invariant technique is used to determine the existence of composite services fulfilling the user＇s input/output requirements. Two algorithms are presented for obtaining the Petri net models of the composite Web services which satisfy not only the user＇s input/output requirements but also the user＇s behavioral constraints.

关 键 词：WEB服务 WEB服务组合 HORN子句 PETRI网 T-不变量 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]