基于服务的Agent社会组织研究

Web Service应用上的人工架构模式成为了其被高度重用的瓶颈。通过Agent对Web Service的封装能极大地改善WebService资源在应用上的主动性及智能性。针对Web Service封装后所形成的Agent服务,给出了基于服务本体及Agent服务描述语言(ASDL)的服务发现方法,并在此基础上给出了基于服务的Agent社会组织机制。实际应用证明方法可行有效。     

服务关系及其在面向服务计算中的应用

在面向服务计算模式中,传统的UDDI、ebXML服务注册中心无论是服务发现,还是组合与交互方面都面临着信息共享和过程中介的难题.文中结合语义Web(Semantic Web)和社会化网络(Social Networking)技术,显式地定义服务间的交互关系(简称服务关系),并将它们融入到服务注册中心的组织、构建及服务计算过程中,将可用Web服务组织成具有丰富语义信息、基于业务上下文和交互关系的服务生态系统.文章首先分析并定义了参数、操作和服务三个层级的服务关系;接着详细讨论了服务关系挖掘的技术细节,包括Web服务的语义标注、服务关系提取、利用等;最后是相关实验数据及结果分析.将语义推理和关系演算引入到服务发现、组合、交互过程中,可以促进和便利服务计算,也是朝向服务互联网(Internet of Services)迈出的重要一步.     

Combining query-by-example and query expansion for simplifying web service discovery

The vision of a worldwide computing network of services that Service Oriented Computing paradigm and its most popular materialization, namely Web Service technologies, promote is a victim of its own success. As the number of publicly available services grows, discovering proper services is similar to finding a needle in a haystack. Different approaches aim at making discovery more accurate and even automatic. However they impose heavy modifications over current Web Service infrastructures and require developers to invest much effort into publishing and describing their services and needs. So far, the acceptance of this paradigm is mainly limited by the high costs associated with connecting service providers and consumers. This paper presents WSQBE+, an approach to make Web Service publication and discovery easier. WSQBE+ combines open standards and popular best practices for using external Web services with text-mining and machine learning techniques. We describe our approach and empirically evaluate it in terms of retrieval effectiveness and processing time, by using a data-set of 391 public services.     

Research on dynamic business composition based on web service proxies

Web services-based business composition brings a number of advantages to the enterprise application development. How to select and compose the web services based on their functionality and QoS (Quality of Service) dynamically prove to be more and more important. In this paper we develop a proxy-based framework to compose Web services dynamically. The framework is featured with a QoS model, an effective service discovery and selection algorithms to facilitate the dynamic integration of Web services and management of abnormalities. Furthermore, a business process constructing method based on service slice is put forward to satisfy the users’ personalized requirements more effectively and flexibly. Our study concerns both functionality and QoS characteristics of Web services to identify the optimal business process solutions. A Complete case study is also included in this paper and the performance demonstrated that the framework and algorithms can provide a tangible and reliable solution to dynamic Web service composition and adaptation.     

一种基于语义的Web服务匹配算法

概要:在当前Web服务发现过程中,采用基于数据类型和关键词的搜索匹配算法,而忽略了人类语言表达的多样性。通常服务请求者对需求描述不能很好符合Web服务匹配算法的要求,是造成服务匹配率较低的主要原因。本文探讨一种基于语义的Web服务匹配算法,分别对服务提供者注册Web服务,服务请求者提交Web服务请求以及服务注册中心进行Web服务匹配等三个过程提出了改进算法,从而可提高服务匹配率。     

一种支持QoS的自适应Web服务发现模型

服务质量是Web服务发现中的关键问题.该文提出一种支持QoS的自适应Web服务发现模型,在满足用户对Web服务功能需求的基础上,依据QoS等非功能性指标对Web服务进行选择和排序,并给出服务的选择排序算法,该算法以服务注册参数、用户反馈信息和实时监测数据为依据,能动态地对服务的非功能性指标进行评价,返回最合适的服务给用户.实验证明,该模型有效地提高了系统的可用性.     

A trustworthy QoS-based collaborative filtering approach for web service discovery

Many network services which process a large quantity of data and knowledge are available in the distributed network environment, and provide applications to users based on Service-Oriented Architecture (SOA) and Web services technology. Therefore, a useful web service discovery approach for data and knowledge discovery process in the complex network environment is a very significant issue. Using the traditional keyword-based search method, users find it difficult to choose the best web services from those with similar functionalities. In addition, in an untrustworthy real world environment, the QoS-based service discovery approach cannot verify the correctness of the web services’ Quality of Service (QoS) values, since such values guaranteed by a service provider are different from the real ones. This work proposes a trustworthy two-phase web service discovery mechanism based on QoS and collaborative filtering, which discovers and recommends the needed web services effectively for users in the distributed environment, and also solves the problem of services with incorrect QoS information. In the experiment, the theoretical analysis and simulation experiment results show that the proposed method can accurately recommend the needed services to users, and improve the recommendation quality.