【作者】 江阳；

【导师】 李建华；

【作者基本信息】 中南大学 ， 计算机科学与技术， 2011， 硕士

【摘要】 随着Web服务技术的快速发展,越来越多的稳定易用的Web服务共享在网络上,但是单个Web服务的功能一般比较简单,很多情况下不能满足用户的实际需要,为了更加充分地利用这些共享的Web服务,有必要将这些Web服务组合起来,提供更为强大的功能,满足用户的实际需求。Web服务组合验证能提前发现Web服务组合中存在的缺陷,是提高Web服务组合执行的成功率和增强用户满意度的关键,对Web服务组合的正确运行具有十分重要的意义。本文的主要工作如下：1.提出一种基于与或图的Web服务组合方法。该组合方法可分为两个步骤,首先根据已有可用的Web服务和用户提出的服务请求,从服务请求的输出对象到输入对象反向生成服务参数与或图。然后在与或图中搜索能够满足服务请求的服务组合图,该方法可以提高服务组合的效率和成功率。2.提出一种利用Pi演算对Web服务组合的正确性进行验证的方法。先用Pi演算对Web服务组合进行建模,然后在Pi演算辅助工具MWB中验证该服务组合方案是否存在死锁和是否满足用户需求。3.利用Pi演算对Web服务组合中一个服务是否可以被另一个服务替换进行验证。先用Pi演算对进行服务替换后新的组合服务进行建模,并根据新的组合服务是否兼容来判断该服务替换的可行性。本文对Web服务组合和Web服务组合验证进行了深入的研究,提出了有效的解决方案,对于推进Web服务组合技术的理论研究和应用具有一定的价值。更多还原

【Abstract】 With the rapid development of Web service technology, more and more stable and ease-to-use Web services are shared on the Internet. But the function of a single Web service is simple, it can not meet the actual needs of users in many cases.In order to utilize the shared Web services more fully, it is necessary to combine these Web services together so that these Web services can provide more powerful functions and meet the actual needs of users. Verification of Web service composition can find existed defects in Web service composition in advance. It is a key to improve the success rate of execution of Web service composition and to enhance the user’s satisfaction degree, and it has very important significance to the correct operation of Web service composition. The major works are as follows:1. Proposing a Web service composition method based on AND/OR graph. It includes two steps. First, according to the existing Web services available and the user’s service request, generating the service parameter AND/OR graph from the output object of service request to input object of service request reversely. Then searching for the service composition graph which can meet the service request in the AND/OR graph. This method can improve the efficiency and success rate of service composition.2. Proposing a method which uses Pi calculus to verify the correctness of Web service composition. First using the Pi calculus to model Web service compostion, then verifying the service composition method whether it exists deadlocks and can meet user’s needs or not.3. Using Pi calculus to verify if a service can be substituted by another service. At first using Pi calculus to model the new compositional service after service substitution. Determining the feasibility of the service substitution according to whether the new service composition is compatible.In this paper, Web service composition and Web service composition verification are conducted in-depth research and effective solutions are put forward, which have certain meaning for promoting theory research and application of Web service composition.更多还原