基于UDDI的Web服务发现研究

基于UDDI的Web服务发现机制仅提供了基于语法层关键字的匹配方法,缺乏语义推理的支持.在相关研究的基础之上,提出了一个基于UDDI的Web服务注册/发现方法,使得服务提供者可以发布OWL-S语言描述的服务,并发布到UDDI注册中心.在传统UDDI注册中心之外新建一层Sem-UDDI注册中心,使用Sem-UDDI注册中心来存储服务的语义信息和服务相关的分类属性,并由服务匹配引擎计算服务属性之间的语义相似度,从而支持基于语义的推理查询,增强了UDDI的语义Web服务发现的能力.     

扩展UDDI以支持OWL-S

在对UDDI和OWL-S研究的基础上，提出扩展UDDI，以支持用OWL-S描述的Web服务的推广和请求，OWL-S可以通过服务提供功能的语义信息来描述服务，以实现更好的服务发现。而且，也提出了一种基于服务的输入输出描述本体的匹配机制。通过扩展JUDDI实现了OWL-S信息的存储和匹配机制。实验证明这是实现语义Web服务注册和发现的一种合理机制。     

利用聚类优化语义Web服务发现

针对传统Web服务缺乏语义造成注册中心返回结果不精确的问题,提出了一种用OWL-S提供语义支持,并据语义相似度将Web服务聚类的解决方法。该方法应用OWL-S实现Web服务的语义描述,采用凝聚的层次聚类的Single-Link算法将相似Web服务聚类,快速定位并返回最合适的服务,提高了服务发现的精确性。     

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.     

一种基于分布式哈希表的Web服务目录系统

分析了集中式UDDI注册中心存在的缺点。结合P2P技术，基于分布式哈希表提供的高效的数据定位功能，提出了一种分布式Web服务目录系统，讨论了该系统下Web服务的发布与发现过程以及目录系统的维护。在该服务目录系统中，服务的描述信息分布在各个节点上，能够克服集中式UDDI注册中心的缺陷。     

Web services lookup: a matchmaker experiment

UDDI is a standard registry for Web services, but so far its search functionality has been limited to keyword search. These authors propose a UDDI enhancement called Matchmaker, which supports semantic service capability discovery. Since September 2003, they have deployed Matchmaker in one of four official UDDI registries operated by NTT-Communications. In this article, they introduce Matchmaker and illustrate client tools that lower the threshold for using semantics in service discovery. Experiments show that Matchmaker search consumes about 5 seconds more time than a typical keyword-based search. The authors also collected user information through questionnaires and by observation of search behavior.     

Use of ebRIM-based CSW with sensor observation services for registry and discovery of remote-sensing observations

Recent advances in Sensor Web geospatial data capture, such as high-resolution in satellite imagery and Web-ready data processing and modeling technologies, have led to the generation of large numbers of datasets from real-time or near real-time observations and measurements. Finding which sensor or data complies with criteria such as specific times, locations, and scales has become a bottleneck for Sensor Web-based applications, especially remote-sensing observations. In this paper, an architecture for use of the integration Sensor Observation Service (SOS) with the Open Geospatial Consortium (OGC) Catalogue Service-Web profile (CSW) is put forward. The architecture consists of a distributed geospatial sensor observation service, a geospatial catalogue service based on the ebXML Registry Information Model (ebRIM), SOS search and registry middleware, and a geospatial sensor portal. The SOS search and registry middleware finds the potential SOS, generating data granule information and inserting the records into CSW. The contents and sequence of the services, the available observations, and the metadata of the observations registry are described. A prototype system is designed and implemented using the service middleware technology and a standard interface and protocol. The feasibility and the response time of registry and retrieval of observations are evaluated using a realistic Earth Observing-1 (EO-1) SOS scenario. Extracting information from SOS requires the same execution time as record generation for CSW. The average data retrieval response time in SOS+CSW mode is 17.6% of that of the SOS-alone mode. The proposed architecture has the more advantages of SOS search and observation data retrieval than the existing sensor Web enabled systems.     

Sharing geospatial provenance in a service-oriented environment

One of the earliest investigations of provenance was inspired by applications in GIS in the early 1990’s. Provenance records the processing history of a data product. It provides an information context to help users determine the reliability of data products. Conventional provenance applications in GIS focus on provenance capture, representation, and usage in a stand-alone environment such as a desktop-based GIS software system. They cannot support wide sharing and open access of provenance in a distributed environment. The growth of service-oriented sharing and processing of geospatial data brings some new challenges in provenance-aware applications. One is how to share geospatial provenance in an interoperable way. This paper describes the development of provenance service for geospatial data products using the ebXML Registry Information Model (ebRIM) of a geospatial catalog service, which follows the interface specifications of the OGC Catalogue Services for the Web (CSW). This approach fits well the current service stack of the GIS domain and facilitates the management of geospatial data provenance in an open and distributed environment.     

基于本体的远程医疗语义Web服务发现方法研究

由于现有医疗信息系统之间的异构性,使得各系统间的信息交换无法正常进行。基于SOA的远程医疗诊断系统的出现,可以很好地解决各种异构系统的集成问题。但是,目前的Web服务注册和发现协议如UDDI是基于关键字的检索技术,无法描述Web服务的语义信息,这使得基于传统协议的Web服务发现算法无法自动匹配一些符合要求的服务。为了解决上述问题,基于SOA思想提出了一种基于本体的语义Web服务模型,并给出了相应的Web服务发现算法。该模型能够更准确有效地描述Web服务,使得计算机可以完成自动服务匹配,提高了查全率和查准率。     

一种基于访问控制的安全Web服务发现机制

当前的Web服务发现机制大多依赖集中式的统一描述、发现和集成注册中心,但组织机构出于安全和地域的考虑,倾向于构建私有的分布式注册中心,只有注册且可信的请求者才能浏览到他们有权限访问的服务信息。该文给出Web服务发现阶段基于角色的访问控制模型RBAC4WSD,发现代理依照服务提供者指定的安全策略对请求者实施访问控制,并以跨国公司内部的文档服务为例介绍原型系统的实现。     

基于UDDI的语义Web信用评估服务研究

UDDI服务注册机的服务发现提供了简单的基于关键字的搜索方法,但缺乏对语义推理的支持。论文在对UD鄄DI服务发现基本模型的研究基础上加入了语义推理,并运用到电子商务信用评估服务发现中。提出了基于UDDI的语义Web信用评估服务系统的结构,着重介绍了基于本体论的电子商务信用评估元模型,并利用信用评估元模型构造信用服务原子模型。     

A combinatory framework of Web 2.0 mashup tools,OWL-S and UDDI

The increasing number of Web 2.0 applications, such as wikis or social networking sites, indicates a movement to large-scale collaborative and social Web activities. Users can share information, add value to Web applications by using them or aggregate data from different sources creating Web applications (mashups) using specialized tools (mashup tools). However, Web 2.0 is not a new technology, but it rather embraces a new philosophy, treating the Internet as a platform. Several issues related to the Semantic Web vision, such as interoperability or machine understandable data semantics, are not tackled by Web 2.0. In this paper, we present our effort to combine semantic Web services (SWS) discovery frameworks, UDDI repositories and existing mashup tools in order to enhance the procedure of developing mashups with semantic mashup discovery capabilities. Towards this end, we introduce a social-oriented extension of OWL-S advertisements, their mapping algorithm on UDDI repositories and a semantic mashup discovery algorithm. Finally, we elaborate on the way our framework has been realized using the Yahoo Pipes mashup tool.     

基于语义相似度的Web服务发现研究

Web服务的大量涌现对服务发现提出了挑战,UDDI上基于关键词和简单分类的服务发现机制已经不能很好满足需要。文中在分析现有相关研究的基础上,给出了一种基于语义相似度的Web服务发现方法。该方法充分利用服务中存在的语义信息,针对服务请求和广告服务中描述的功能进行匹配,并通过语义相似度来衡量两者匹配的程度。文中具体给出了服务间语义相似度的计算方法并通过示例说明了服务匹配的过程。