工作流管理系统Web客户端的设计与实现

工作流技术通过使用计算机来支持企业经营过程的运行,并实现了对企业经营过程的管理与控制。随着Internet应用的普及和Web技术的发展,基于Web的工作流管理服务为异地办公及跨企业的合作提供了良好的基础,采用Web技术已成为新一代工作流管理系统的主要特征。文章研究开发的工作流管理系统原型CIMFlow将Web技术与CORBA相结合,给出了基于Web的过程访问和控制功能的设计与实现方法。     

一个Web服务管理框架设计方案

简单地说,Web服务(Web Services)就是自描述模块化的业务应用程序,它可以通过可编程接口经由Internet将业务逻辑发布为服务,并通过XML,SOAP,WSDL,UDDI和ebXML等标准协议来查找、订阅和调用这些服务。文中针对日益增长的Web服务管理的需求以及存在的问题,对Web服务管理(Web Service Management)、Web服务管理原则和管理模式等做了深入的研究探讨,提出了一个Web服务管理框架设计方案,同时阐明了框架的内部组成模块以及各部分之间的相互关系。     

基于Internet工作流的复合Web服务框架

实现灵活方便的企业业务集成一直是信息领域的核心问题，也是B2B电子商务应用的关键．为此将Web服务和传统的工作流技术相结合，设计并实现了支持复合Web服务运行和管理的框架WSFlow．给出了WSFlow的总体结构，描述了其中的关键技术，包括Web服务与工作流活动的动态配置和绑定技术，复合Web服务流程的动态修改以及复合Web服务的运行监控等技术．     

Integrating AJAX and Web Services for Cooperative Image Editing

AJAX (asynchronous JavaScript and XML) is a powerful Web development model for browser-based Web applications. While Web services essentially are universally accessible software components deployed on the Web and designed to support interoperable machine-to-machine interaction over a network. Because technologies that support both AJAX and Web services are XML-based, the two can leverage each others' strengths. More and more companies and organizations are taking advantage of this relationship, working to improve their Web applications through AJAX and Web services. Our system integrates the two for Web-based cooperative image editing. For message exchange delays and browser security limitations have hampered Web-based cooperative image editing. This integration resolves these issues and offers a framework for generic cooperative business processes     

面向跨企业多方协同应用的Web服务安全模型

现有的Web服务安全工具仅提供单个服务的安全策略配置功能,忽略了业务流程层面的安全需求。为此,提出一种面向跨企业多方协同应用的Web服务安全模型,将Web服务安全建模、部署与监控过程,融合到企业业务流程管理过程中。在此基础上构造基于Secure-WSCDL的建模工具、转换工具和监控工具,实现SOA架构下业务模型与安全建模在软件工程生命周期中的同步。通过简化的国际贸易进出口流程实例,验证了该模型与相应工具的有效性。     

基于代理和BPEL4WS的Web服务合成与实现

Web服务的交互和实现被推荐通过软件代理来实现.Web服务目前还不能很好地支持动态、自适应的服务组合和分布式业务流程.软件代理在建模、知识表达和交互等技术上的优势,能够强化Web服务的交互和动态应用能力.基于代理和面向流程建模的BPEL4WS,可以实现Web服务面向业务应用的合成与执行,支持多个协同的业务流程及其动态配置.系统分析了代理、BPEL4WS和Web服务整合的技术与实现方案,利用JADE平台开发了相关的测试模型,并且以网上拍卖为案例,验证了所提方案及实现.     

基于OWL—S和HTN的Web服务组合原型系统的研究

Web服务是近年发展的一种分布式技术,引起了越来越多研究者的关注。随着网络上Web服务技术描述的信息系统数量的不断增加,将现有的业务流程进行组合以满足较为复杂的业务系统成为当前发展的主要趋势。此外,由于Web服务所处环境的复杂性和动态性,使得Web服务组合任务变得非常困难。因此,Web服务组合逐渐成为语义Web服务领域研究的热点和难点。描述了一个基于OWL—S和HTN的Web服务组合框架,并详细介绍了如何利用HTN规划解决Web服务组合问题的算法思想。通过学生选课服务实验,验证了该方法的可行性。     

An analysis of the driving forces for Web services adoption

Web services are supported by major IT vendors and have been adopted by some enterprises in various applications. However, due to the hype surrounding Web services, information technology (IT) personnel and business managers often have difficulty assessing the potential uses, impacts, and benefits of Web services. Based on literature review and technical information, as well as field and Web-based case studies, we have developed a framework for analyzing the driving forces for Web services adoption. The framework and detailed benefits analysis model can be used by IT and business strategy planners to identify technical options and business opportunities, as well as to formulate Web services implementation strategies.     

The WSLA Framework: Specifying and Monitoring Service Level Agreements for Web Services

We describe a novel framework for specifying and monitoring Service Level Agreements (SLA) for Web Services. SLA monitoring and enforcement become increasingly important in a Web Service environment where enterprise applications and services rely on services that may be subscribed dynamically and on-demand. For economic and practical reasons, we want an automated provisioning process for both the service itself as well as the SLA managment system that measures and monitors the QoS parameters, checks the agreed-upon service levels, and reports violations to the authorized parties involved in the SLA management process. Our approach to these issues is presented in this paper. The Web Service Level Agreement (WSLA) framework is targeted at defining and monitoring SLAs for Web Services. Although WSLA has been designed for a Web Services environment, it is applicable as well to any inter-domain management scenario, such as business process and service management, or the management of networks, systems and applications in general. The WSLA framework consists of a flexible and extensible language based on XML Schema and a runtime architecture comprising several SLA monitoring services, which may be outsourced to third parties to ensure a maximum of objectivity. WSLA enables service customers and providers to unambiguously define a wide variety of SLAs, specify the SLA parameters and the way they are measured, and relate them to managed resource instrumentations. Upon receipt of an SLA specification, the WSLA monitoring services are automatically configured to enforce the SLA. An implementation of the WSLA framework, termed SLA Compliance Monitor, is publicly available as part of the IBM Web Services Toolkit.     

支持演化的Web服务框架研究

经过多年的研究和实践,软件配置管理已经成为一种成熟的软件开发规范和技术。然而对于基于Web服务的EAI(企业应用集成)来说,这依然是一个难题。论文提出了一个支持服务演化的Web服务框架。这个框架引入基于服务项的权限控制和动态服务配置管理来构成整个面向EAI的Web服务系统。这样,EAI环境中的各Web服务就可以在系统的配置管理支持下进行演化。     

基于Web Service的企业知识管理研究

在分析企业知识管理的定义、内容、过程及需求的基础上得出当今知识管理的关键点在于不同企业、不同地区的知识及信息的共享，并且提出了基于Web service的松散耦合的企业知识管理框架，为企业信息化的发展提供了完善的应用集成解决方案。     

Industrial application integration using the unification approach to agent-enabled semantic SOA

Within the enterprise, information infrastructure as the mean to bring together different software applications is the key component to enable cooperation and information and knowledge exchange in an open-distributed environment. The paper addresses the issues of industrial application integration in business processes using agent-enabled service-oriented architectures (SOA). In this paper, we show that agent-enabled SOA can play an important role for service integration. Our framework combines Web services (WS) and intelligent agent technologies orchestrated by a business process management system. This framework looks for unification of agent and WS service models, is grounded in a semantic SOA of an agent platform and is supported by the Component Agent Platform Over .NET Framework agent platform tools. We describe the architecture and illustrate the approach by an industrial application scenario from petroleum wells’ drilling.     

一个基于Petri网的Web服务组合模型

作为企业应用集成的重要手段，Web服务组合需要建立可靠的表达和分析方法。因此，基于Petri网技术定义一个Web服务组合模型，将组合Web服务的要索映射到Petri网结构。利用Petri网提供的分析技术，辅助复杂业务流程的建模，并分析验证其正确性和性能。     

A layered architecture for flexible Web service invocation

Web service composition is emerging as an interesting approach to integrate business applications and create intra‐organizational business processes. Single Web services are combined to create a complex Web service that will realize the process business logic. Once the process is created, it is executed by an orchestration engine that invokes individual Web services in the correct order. However, Web services composing the workflow sometimes become unavailable during the run‐time phase, blocking process execution. This paper describes an architecture that allows the flexible orchestration of business processes. With this approach, Web services composing the process can be automatically substituted with other compatible Web services during process execution. A methodology is defined to evaluate Web service compatibility based on interface matching, in order to select substitutable Web services. Copyright © 2005 John Wiley & Sons, Ltd.     

A user-centric approach to service creation and delivery over next generation networks

Next Generation Networks (NGN) provide Telecommunications operators with the possibility to share their resources and infrastructure, facilitate the interoperability with other networks, and simplify and unify the management, operation and maintenance of service offerings, thus enabling the fast and cost-effective creation of new personal, broadband ubiquitous services. Unfortunately, service creation over NGN is far from the success of service creation in the Web, especially when it comes to Web 2.0. This paper presents a novel approach to service creation and delivery, with a platform that opens to non-technically skilled users the possibility to create, manage and share their own convergent (NGN-based and Web-based) services. To this end, the business approach to user-generated services is analyzed and the technological bases supporting the proposal are explained.     

工作流管理系统的Web Services协议分析

工作流管理系统是实现业务过程管理的重要工具。工作流系统以Web Services方式运行,需要有语义清晰的WebServices协议支持。文中从分析Web Services的技术层次入手,详细讨论了Wf-XML协议的技术基础及其特点。最后总结了Wf-XML作为工作流系统的Web Services协议的优势和不足之处。     

Quality management in service ecosystems

Service-oriented architectures and Web services mature and have become more widely accepted and used by industry. This growing adoption increased the demands for new ways of using Web service technology. Users start re-combining and mediating other providers’ services in ways that have not been anticipated by their original provider. Within organisations and cross-organisational communities, discoverable services are organised in repositories providing convenient access to adaptable end-to-end business processes. This idea is captured in the term Service Ecosystem. This paper addresses the question of how quality management can be performed in such service ecosystems. Service quality management is a key challenge when services are composed of a dynamic set of heterogeneous sub-services from different service providers. This paper contributes to this important area by developing a reference model of quality management in service ecosystems. We illustrate the application of the reference model in an exploratory case study. With this case study, we show how the reference model helps to derive requirements for the implementation and support of quality management in an exemplary service ecosystem in public administration.     

A semantical framework to engineering WSBPEL processes

Web services promise the interoperability of various applications running on heterogeneous platforms over the Internet, and are gaining more and more attention. Web service composition refers to the process of combining Web services to provide value-added services, which has received much interest in supporting enterprize application integration. Industry standards for Web Service composition, such as WSBPEL, provide the notation and additional control mechanisms for the execution of business processes in Web service collaborations. However, these standards do not provide support for checking interesting properties related to Web Service and process behavior. In an attempt to fill this gap, we describe a formalization of WSBPEL business processes, that adds communications semantics to the specifications of interacting Web services, and uses a formal logic to model their dynamic behavior, which enables their formal analysis and the inference of relevant properties of the systems being built.     

基于适配的服务协作流程动态管理

服务协作以服务为构造单元,通过组合不同的服务,实现复杂的业务逻辑,并以此为基础构建新的应用.为实现正确的服务协作,服务之间的交互必须是兼容且一致的.适配技术通过构造适配器来弥补服务之间的交互差异,为解决协作的一致性问题提供了有效的方法途径.然而考虑到服务计算环境的动态特性,协作适配器本身应具有动态调整及重新配置的能力,从而避免使其成为协作系统响应动态变化的可适应能力的瓶颈.文中首先给出了一种基于适配的服务协作方法,以保证服务交互的一致性.并针对提出的适配器结构,建立了适配器的执行模型,在此基础上给出了适配器的动态更新方法,使适配器具有可重配置以及动态调整的能力,从而保证了基于适配的服务协作系统的灵活性和动态可适应性.     

Quality of service for workflows and web service processes

Workflow management systems (WfMSs) have been used to support various types of business processes for more than a decade now. In workflows or Web processes for e-commerce and Web service applications, suppliers and customers define a binding agreement or contract between the two parties, specifying quality of service (QoS) items such as products or services to be delivered, deadlines, quality of products, and cost of services. The management of QoS metrics directly impacts the success of organizations participating in e-commerce. Therefore, when services or products are created or managed using workflows or Web processes, the underlying workflow engine must accept the specifications and be able to estimate, monitor, and control the QoS rendered to customers. In this paper, we present a predictive QoS model that makes it possible to compute the quality of service for workflows automatically based on atomic task QoS attributes. We also present the implementation of our QoS model for the METEOR workflow system. We describe the components that have been changed or added, and discuss how they interact to enable the management of QoS.