基于流程树的BPEL4WS中流程服务动态优化方法*

针对服务流程建模语言BPEL4WS难以满足用户个性化需求也无法适应动态环境变化的问题，提出了一种动态优化BPEL4WS中流程服务的方法。该方法给出了一种Web服务交互代价计算模型，用来评价用户对Web服务的偏好程度以及实时环境下Web服务交互的现实代价。将BPEL4WS描述的服务组合流程转换为服务组合流程树，并借助领域本体对流程树节点进行语义检查，消除流程树中不合法的流程组合。通过深度优先遍历流程树，利用单亲遗传算法对流程服务进行优化组合。最后给出应用算例，并对用来优化组合流程服务的单亲遗传算法的适用性与

Dynamic process services optimized combination for BPEL4WS based on process tree

Business process execution language for Web services (BPEL4WS) was difficult to meet the needs of individual users as well as unable to adapt to dynamic changes in the environment. To deal with this problem, the paper presented a method of dynamic process services optimized combination for BPEL4WS, which provided a Web service interactive cost calculation model used to evaluate user preferences for Web service and the actual cost of Web services interaction in the actual environment. Firstly, converted service process described by BPEL4WS into a service process tree, which was checked by domain ontology in order to prevent the logic errors of service process composition. Then, dynamic optimized the orders of service process by partheno genetic algorithm in the process of depth-first traversal of the process tree. Finally gave an application case to validate the proposed approach and the adaptability and efficiency of partheno genetic algorithm, which was used to optimize service process, is checked by experiment results.