语义网服务中的本体综述

作为实现下一代Web的集成方案,语义网服务将语义Web技术和Web服务技术相结合,以支持Web服务的自动发现、选择、合成和执行.本体是语义网服务的理论基础.介绍了Web资源描述本体OWL和Web服务描述本体的概况,并对3种主流的Web服务语义描述框架进行对比分析,为语义网服务中本体的创建提供基础知识.研究了语义网服务中存在的各层次的本体异构问题,明确了语义网服务中本体集成的主要研究方向.     

Context-aware agents for user-oriented web services discovery and execution

Service-oriented computing (SOC) suggests that the Internet will be an open repository of many modular capabilities realized as web services. Organizations may be able to leverage this SOC paradigm if their employees are able to ubiquitously incorporate such capabilities and their resulting information into their daily practices. It is impractical to assume that human users will be able to manually search vast distributed repositories at real-time. This paper presents an architecture, Software Agent-Based Groupware using E-services (SAGE), that incorporates the use of intelligent agents to integrate human users with web services. SAGE provides background search and discovery approaches, thus enabling human users to exploit service-based capabilities that were previously too time-consuming to locate and integrate. We present a multi-agent system where each agent learns the rule-based preferences of a human user with regards to their current operational “context” and manages the incorporation of relevant web services. Recommended by: Djamal Benslimane and Zakaria Maamar     

基于过滤级的语义Web服务发现策略

语义Web与Web services有很强的互补性,在现有技术条件下二者的统一构建了新一代Web服务--语义Web服务.描述了语义Web服务发现的任务,提出了一种基于过滤级的发现策略,最后给出了各级匹配的具体算法.基于过滤级的语义Web服务发现策略明显地缩减了服务匹配的空间,并大大提高了服务发现的时间效率.同时,相关技术还在进一步的研究中.     

基于扩展语义接口的Web服务动态组合方法

自动地根据用户请求进行服务的动态组合是目前Web服务领域的关键问题.针对该问题,提出了一种基于本体的服 务动态组合方法,设计并实现了一个服务动态组合原型.首先Web服务按照一定规则被抽象为本体模型,然后通过分析所 构造服务的模型来实现服务的匹配,最后利用BPEL4ws对匹配生成的服务组合序列来进行自动的组合.实验结果表明,该 方法细化了服务接口的语义,并且在发现结果上有更高的准确性.     

一种语义Web服务的多层次匹配方法

现有的语义Web服务发现方法大多采用匹配等级来筛选服务，查找到的服务粒度较大，也没有考虑服务质量。对OWL-S语言进行扩展，增加对QoS（服务质量）的描述，提出了五层次三阶段的多层次匹配过程，采用语义相似度进行匹配。实验结果表明该匹配方法能够保证查找的查准率和查全率。     

Mass argumentation and the semantic web

The World Wide Web (WWW) can be seen as an ideal platform for enhancing argumentative expression and communication, due to its ubiquity and openness. Much argumentation takes place on personal blogs and on unstructured or semi-structured discussion forums. Recently, an increasing number of Web 2.0 applications provide specific support for large-scale socially-contributed argumentative content. When compared with traditional methods of Web discourse, these tools enable better visualisation, navigation and analysis of the ‘state of the debate’ by participants and, potentially, by automated tools. In this paper, I outline some potential benefits of Semantic Web techniques in supporting mass-scale, socially-contributed argument tagging. I also present some recent research in this direction.     

基于语义的Web服务发现算法优化

服务发现的精确度和对服务请求者的响应速度随着发布的Web服务的数量增多显得日益重要.确保服务发现精度的同时,提出一种改进服务匹配的算法即服务发现提前匹配算法,通过有效地利用已计算出来的匹配程度的信息以减少匹配操作,缩短对请求者的响应时间.为了能及时地更新和删除过时的服务,通过改进相应的数据存储结构,提出了一种维护服务的算法,并进行了相关的理论和实验上的性能分析.实验结果表明算法在很大程度上缩短了对服务请求的响应时间.     

基于证书的语义Web服务访问控制方法

为了实现语义Web服务环境中的访问控制机制,研究了基于证书授权的访问控制方法.在对语义Web服务的访问控制需求进行分析的基础上,提出了将简单公钥基础设施/简单分布式安全基础设施(SPKI/SDSI)证书与OWL-S本体描述集成的访问控制方法,该方法将访问控制描述与服务功能描述集成在一个统一的框架中,既便于管理又提高了用户访问Web服务的效率.     

Towards ubiquitous tourist service coordination and process integration: A collaborative travel agent system architecture with semantic web services

With the recent advances in Internet and mobile technologies, there are increasing demands for ubiquitous access to tourist information systems for service coordination and process integration. However, due to disparate tourist information and service resources such as airlines, hotels, tour operators, it is still difficult for tourists to use them effectively during their trips or even in the planning stage. Neither can current tourist portals assist tourists proactively. To overcome this problem, we propose a Collaborative Travel Agent System (CTAS) based on a scalable, flexible, and intelligent Multi-Agent Information System (MAIS) architecture for proactive aids to Internet and mobile users. We also employ Semantic Web technologies for effective organization of information resources and service processes. We formulate our MAIS architecture for CTAS further with agent clusters based on a case study of a large service-oriented travel agency. Agent clusters may comprise several types of agents to achieve the goals involved in the major processes of a tourist’s trip. We show how agents can make use of ontology from the Semantic Web to help tourists better plan, understand, and specify their requirements collaboratively with the CTAS. We further illustrate how this can be successfully implemented with Web service technologies to integrate disparate Internet tourist resources. To conclude, we discuss and evaluate our approach from different stakeholders’ perspectives.

Applying intelligent agents and semantic web services in eGovernment environments

The increasing volume of eGovernment‐related services is demanding new approaches for service integration and interoperability in this domain. Semantic web (SW) technologies and applications can leverage the potential of eGovernment service integration and discovery, thus tackling the problems of semantic heterogeneity characterizing eGovernment information sources and the different levels of interoperability. eGovernment services will therefore be semantically described in the foreseeable future. In an environment with semantically annotated services, software agents are essential as the entities responsible for exploiting the semantic content in order to automate some tasks, and so enhance the user's experience. In this paper, we present a framework that provides a seamless integration of semantic web services and intelligent agents technologies by making use of ontologies to facilitate their interoperation. The proposed framework can assist in the development of powerful and flexible distributed systems in complex, dynamic, heterogeneous, unpredictable and open environments. Our approach is backed up by a proof‐of‐concept implementation, where the breakthrough of integrating disparate eGovernment services has been tested.     

Towards runtime discovery, selection and composition of semantic services

Service-orientation is gaining momentum in distributed software applications, mainly because it facilitates interoperability and allows application designers to abstract from underlying implementation technologies. Service composition has been acknowledged as a promising approach to create composite services that are capable of supporting service user needs, possibly by personalising the service delivery through the use of context information or user preferences. In this paper we discuss the challenges of automatic service composition, and present DynamiCoS, which is a novel framework that aims at supporting service composition on-demand and at runtime for the benefit of service end-users. We define the DynamiCoS framework based on a service composition life-cycle. Framework mechanisms are introduced to tackle each of the phases and requirements of this life-cycle. Semantic services are used in our framework to enable reasoning on the service requests issued by end-users, making it possible to automate service discovery, selection and composition. We validate our framework with a prototype that we have built in order to experiment with the mechanisms we have designed. The prototype was evaluated in a testing environment using some use case scenarios. The results of our evaluation give evidences of the feasibility of our approach to support runtime service composition. We also show the benefits of semantic-based frameworks for service composition, particularly for end-users who will be able to have more control on the service composition process.     

A systematic review on the functional testing of semantic web services

Semantic web services are gaining more attention as an important element of the emerging semantic web. Therefore, testing semantic web services is becoming a key concern as an essential quality assurance measure. The objective of this systematic literature review is to summarize the current state of the art of functional testing of semantic web services by providing answers to a set of research questions. The review follows a predefined procedure that involves automatically searching 5 well-known digital libraries. After applying the selection criteria to the results, a total of 34 studies were identified as relevant. Required information was extracted from the studies and summarized. Our systematic literature review identified some approaches available for deriving test cases from the specifications of semantic web services. However, many of the approaches are either not validated or the validation done lacks credibility. We believe that a substantial amount of work remains to be done to improve the current state of research in the area of testing semantic web services.     

移动计算中基于Mobile Agent的Web Services订阅调用模型

在分析了移动环境的特点以及传统J2ME应用程序Web Services调用的问题之后,针对传统移动环境下调用Web Ser-vices存在的问题,提出了基于Mobile Agent并结合订阅的Web Services调用模型,讨论了该模型的原理以及方法,提出了简单消息通信模式,代理服务器和订阅机制以及移动代理迁移策略.最后,结合该改进模型在中石化胜利油田中的实际应用,总结了它适用于移动环境的几个特点,比较了改进模型与传统模型调用Web Services的效率,表明了其正确性和适用性.     

基于UDDI的语义Web服务发现研究

目前基于UDDI的Web服务发现机制仅提供了简单的基于关键字的搜索方法,缺乏对语义推理的支持。因此给出了一种基于UDDI的语义Web服务发现的架构,通过把Web服务的语义描述发布到UDDI注册中心,并扩展查询API的规范,在服务查找中加入语义推理,从而增强了UDDI的语义Web服务发现的能力。