【作者】 赵磊；

【导师】 李登道；

【作者基本信息】 山东科技大学 ， 计算机应用技术， 2007， 硕士

【摘要】 Web服务是一种基于XML的新技术，它解决了复杂的网络计算环境下各种异构系统之间资源不便共享等问题。语义Web的出现，为Web服务的描述增加了语义信息，使得计算机之间以及计算机与人类能够更好的彼此合作。由此而产生的语义Web服务更是以智能逻辑推理，服务自动发现和自动组合为研究目标。本文在分析了语义Web、OWL-S的基础上，结合XML、Ontology等技术对OWL-S语言进行了扩展，在其基础上增加了ServiceCredit元素来描述服务的真实性和性能，从而形成了新的语义Web服务描述语言EOWL-S。由于新增ServiceCredit元素中的信息需要由一个服务提供者和用户之外的第三方进行动态更新，因此在原有服务注册中心的基础上增加了ServiceCredit更新功能，设计并实现了ServiceCredit的更新算法。在此基础上，本文给出了基于ServiceCredit的服务选择方法。随后，结合Agent技术对语义Web服务自动组合方法进行了研究，设计并实现了语义Web服务自动组合多Agent系统SWSACS，并给出了SWSACS的应用实例。本文的主要工作有：对原有OWL-S进行扩展，提出了EOWL-S。OWL-S从服务做什么，服务如何工作和如何访问服务三个方面对服务进行了描述，这些信息均由服务提供者给出。EOWL-S在此基础上增加了一个能够描述服务真实性和服务性能的元素ServiceCredit，并由第三方对其进行更新。构造了ServiceCredit更新模型。由于ServiceCredit是用于服务评定的，需要一个公证的第三方来负责对其更新，因此，这部分工作由服务注册中心完成。本文在原有的服务注册中心的基础上增加了ServiceCredit更新功能，并给出了ServiceCredit更新算法。构造了基于ServiceCredit的服务选择方法。服务查找分为服务匹配和服务选择两个阶段，服务选择是针对经过服务匹配后的服务进行选择。设计并实现了语义Web服务自动组合系统SWSACS。该系统为用户提供了一个系统入口，用户通过该入口定制服务请求。用户定制服务后，由SWSACS调用语义Web服务注册中心的服务查找功能进行服务查找，自动完成服务的组合以及服务组合的调用，并最终向用户返回服务组合执行的结果。更多还原

【Abstract】 Web service is a new technology based on XML. It can solve the problems amongheterogeneous systems in complex network environments such as the problem of beinginconvenient to share resources. The appearance of semantic web adds semantic informationto the description of web service and enables computers and human collaborate well becauseof well defined meanings. Semantic Web Service focuses on intelligent logic reasoning,automatic find and composition of web service.On the basis of analyzing semantic web, OWL-S and combining the technologies of XML,Ontology, this paper extends the OWL-S language and adds the element ServiceCredit todescribe web service’s authenticity and capability. As a result, a new semantic Web servicedescription language EOWL-S is formed. Because the added information needs updatingdynamic by a third-party besides service provider and service requester, we add theServiceCredit updating function on the basis of original service broker, and design theServiceCredit updating algorithm. In this paper, it puts forward a selecting method for servicebased on ServiceCredit. Subsequently, combining with the technology of Agent, this paperdesigns and realizes a semantic web service automatic composition multi-agent systemSWSACS, and provides an application illustrate for SWSACS.The main works of this paper are as follows:It extends the original OWL-S and puts forward EOWL-S. OWL-S describes web servicefrom what OWL-S can do, how web service works and how to access web services, which areall provided by service provider. EOWL-S adds an element ServiceCredit to describe theservice’s authenticity and capability, and it is updated by the third-party.It constructs an updating model for ServiceCredit. Because ServiceCredit is used to evaluateweb service and needs a third-party to update it, so this job should be done by service broker.This paper also constructs the update algorithm of ServiceCredit.It puts forward the selecting method for web service based on ServiceCredit. Servicefinding includes service match and service selection which focuses on selecting web servicefrom the results of service match.It designs and realizes an automatic service composition system SWSACA for semantic web service. This system provides an entrance to SWSACS for service requesters. They cancustomize service requests through this entrance. After customizing service, SWSACS will usethe find function of the service broker to find web services, and accomplish the servicecomposition and execution automatically, and retum the results to the service requestereventually.更多还原