面向服务的柔性迁移工作流停靠站设计

在迁移工作流系统中,停靠站服务器是迁移实例的运行支撑平台,必须能够支持多种支撑服务和应用服务的集成,适应运行环境和应用需求的动态变化。基于面向服务的概念,提出了一个可扩展、可定制和可重配置的停靠站服务器结构模型,描述了模型的体系结构和内核结构,讨论了服务组件的集成框架和组织模式,以及应用服务的部署模式等,并结合微内核和组件技术给出了参考实现方案。     

工作流模型研究述评

工作流管理系统由于能够对业务过程进行建模和控制而得到广泛采用,工作流模型则是工作流管理系统理论研究和实际应用的基础.概括了工作流模型的主要研究内容,从建模方法、理论基础等方面对工作流模型的研究现状进行了综述,分析了现有工作流模型存在的不足,探讨了工作流模型的发展趋势,最后进行了总结.     

基于Agent的Web Services自适应工作流模型的研究

如何让企业可以灵敏反应外部环境的变动并快速改变企业内部的流程作业,是传统工作流管理系统面临的最大挑战.提出一种基于Agent的Web Services工作流模型(AW-WFM)来解决这个难题.在这个模型中,基于Agent的技术实现一种工作流协作机制,而Web Services技术为工作流管理系统提供了计算资源.最后,介绍了AW-WFM在上海大学协同办公系统中的应用.     

基于代理的工作流执行服务的探讨

工作流理论不断发展,工作流管理系统也逐渐成为目前研究的热点之一.而工作流执行系统作为工作流管理系统的核心部件,其工作效率也越来越引起人们的关注.通过利用代理技术,提出了一种新的工作流执行服务架构,并对工作流引擎的执行过程进行了分析.     

工作流管理系统核心模型应用研究

在新一轮的运营系统建设中,工作流技术已成为电信运营支撑系统的核心技术。在引入相关概念之后,针对电信业务的特点着重描述了广东电信综合业务支撑系统中工作流管理系统（IBSS）的设计和应用。IBSS工作流模型参考了通用工作流管理平台的特点,尽量满足灵活性和扩展性的要求,同时又针对电信业务的特殊性做了一些处理和优化。事实证明,这些措施起到了简化工作流模型、有效地提高系统效率的作用。     

面向地震网络计算的网格工作流管理系统

针对国家地震网络计算应用系统的需求,将工作流技术引入地震网络计算,实现了国家地震网格工作流管理系统.该系统能够将地震领域的部分专业应用定义为一个工作流来为用户提供服务,对系统中的基本服务进行调度,通过网格中间件进行执行,并对任务进行监视和管理.论述了该系统的框架及相关技术,通过对现有的地震行业典型应用的流程分析,构造出一个工作流实例,简化了类似应用服务的开发过程.     

Modelling and simulation of Network Enabled Capability on service-oriented architecture

Network Enabled Capability (NEC) is the UK Ministry of Defence’s response to the quickly changing conflict environment in which its forces must operate. In NEC, systems need to be integrated in context, to assist in human activity and provide dependable inter-operation. In this paper, we present our research work in the NECTISE project with a focus on the modelling and simulation of service-oriented architecture (SOA) for delivering dependable and sustainable military capability. The simulation results indicate that the proposed architectural model can provide a high-level of reliability and sustainability in the provision of capability in a dynamic environment. Moreover, a NEC demonstration system for regional surveillance is introduced in this paper to illustrate the use of SOA to achieve NEC.     

面向科学过程的工作流技术研究现状与趋势*

介绍了科学工作流技术的起源及发展,分析了科学工作流全生命周期组成及关键技术,主要包括流程建模与描述、流程映射、流程执行与调度以及数据起源管理这四个方面的发展状况,从科学工作流管理系统框架、协同技术和应用现状等方面分析了科学工作流技术的研究现状,分析了目前科学工作流技术中存在的不足,并对其未来发展趋势给出了建议。     

SaaS工作流访问控制模型设计

在SaaS中,人们正逐渐采用基于服务的业务流程来满足企业业务流程的灵活性和定制性。从实现工作流访问控制的角度,应当使工作流访问控制模型与流程模型分离,以支持在流程改变或组织机构变化时减少对彼此的影响。为此,设计和实现了一个面向服务的、支持访问控制模型和流程模型分离的SaaS工作流访问控制模型—RBSWAC(Role-based Service Workflow Accesss Control)。该模型可提高访问控制的适应性和灵活性,实现访问控制模型同流程模型的松耦合和灵活性。     

Supporting agile supply chains using a service-oriented shop floor

The globalized nature of current business environments led to the emergence of new networked enterprise organizational paradigms (supply chains, extended enterprises, virtual enterprises, collaborative networks, etc.) to meet changing requirements and tackle profitable but volatile opportunities overall agility is required.Eventually the shop floor will have to react and accommodate (re)adjustments in the supply chain making it an important piece in the competitiveness puzzle. So far, the research focus has been in high level aspects of supply chain management and the integration of shop floor activities in the process has been left relatively unattended.However, shop floor data is increasingly required in business tools that support decision making. In this context, failing to support agility at shop floor level can compromise the agility of the supply chain.Recent developments in networked information technologies and embedded devices allow enabling intelligence in shop floor rendering it an active and live entity that further enhances the dynamics of the supply chain.The goal of the present work, supported by an implemented test case in the assembly domain, is to demonstrate how one is able to seamless integrate the shop floor with external tools and achieve a highly reconfigurable environment that adapts to changing production requirements and disturbances using service-oriented technology.     

Three practical workflow schedulers for easy maximum parallelism

Runtime scheduling and workflow systems are an increasingly popular algorithmic component in HPC because they allow full system utilization with relaxed synchronization requirements. There are so many special-purpose tools for task scheduling, one might wonder why more are needed. Use cases seen on the Summit supercomputer needed better integration with MPI and greater flexibility in job launch configurations. Preparation, execution, and analysis of computational chemistry simulations at the scale of tens of thousands of processors revealed three distinct workflow patterns. A separate job scheduler was implemented for each one using extremely simple and robust designs: file-based, task-list based, and bulk-synchronous. Comparing to existing methods shows unique benefits of this work, including simplicity of design, suitability for HPC centers, short startup time, and well-understood per-task overhead. All three new tools have been shown to scale to full utilization of Summit, and have been made publicly available with tests and documentation. This work presents a complete characterization of the minimum effective task granularity for efficient scheduler usage scenarios. These schedulers have the same bottlenecks, and hence similar task granularities as those reported for existing tools following comparable paradigms.     

MINI工作流管理系统的设计与实现

对当前的工作流管理系统进行了分类比较，介绍了目前的研究热点和相关项目，设计并实现了一个基于Web的、面向过程的动态MINI工作流管理系统。该系统采用基于XML的MINI工作流过程建模语言描述模型，定义了工作流中的同步和并发处理机制，MINI解析器作为一个独立的组件被单独实现，这使得系统结构灵活，便于扩展。系统主要由工作流建模工具、工作流引擎和客户端工具组成，其中工作流建模工具采用C／S结构，客户端工具采用B／S结构，工作流引擎采用J2EE技术实现。     

Experiments with service-oriented architectures for industrial robotic cells programming

Integration of equipment in industrial robot cells is to an increasing part involved with interfacing modern Ethernet technologies and low-cost mass produced devices, such as vision systems, laser cameras, force–torque sensors, soft-PLCs, digital pens, pocket-PCs, etc. This scenario enables integrators to offer powerful and smarter solutions, more adapted to small and medium enterprises (SMEs), capable of integrating process knowledge and interface better with humans. Nevertheless, programming all these devices efficiently requires too much specific knowledge about the devices, their hardware architectures and specific programming languages, details about system communication low-level protocols, and other tricky details at the system level. To address these issues, this paper describes and analyses two of the most interesting service-oriented architectures (SOA) available, which exhibit characteristics that are well adapted to industrial robotics cells. To compare, discuss and evaluate their programming features and applicability a test bed was specially designed, and the two SOA are fully implemented to program the test bed. Special focus is given to the way services are specified and to the orchestration tools used to manage system logic. The obtained results show clearly that using integrations schemes based on SOA reduces system integration time and are more adapted to industrial robotic cell system integrators.     

工作流技术在办公自动化系统中的应用

工作流技术是办公自动化系统中的核心技术之一。文中对工作流、工作流管理系统的概念和模型做了详细的介绍,提出了一种基于工作流模型的OA系统模型,在此基础上介绍了一个已完成的公文流转子系统中采用的相应技术。     

工作流正确性问题综述*

首先从结构正确性和执行正确性两方面对工作流系统的正确性问题进行了综述。对结构正确性,从模型角度进行了正确性定义、判定依据及判定工具的介绍。对执行正确性,从事务、异常处理两个方面介绍了当前工作流正确性的保障技术。最后,对已有工作流正确性问题的理论和实现技术进行了比较,并总结了这方面的几个研究方向,供研究人员借鉴。     

Service selection and workflow mapping for Grids: an approach exploiting quality‐of‐service information

The advent of heterogeneous and distributed environments, such as Grid environments, made feasible the solution to computational‐intensive problems in a reliable and cost‐effective manner. In parallel, workflows with increased complexity that require specialized systems to deal with them are emerging, so as to carry out more composite and mission‐critical applications. In that rationale, quality‐of‐service (QoS) issues need to be tackled in order to ensure that each application satisfies the corresponding user requirements. Therefore, considering the quality provision aspect as fundamental for enabling Grid applications to become QoS compliant, we present an approach for service selection using QoS criteria. The latter is achieved with a suite of components that allow the different mappings of application workflow processes to Grid services that not only meet the user goals and requirements but also maximize his/her benefit in terms of the offered QoS level. We also demonstrate the operation of the aforementioned suite of components and evaluate its performance and effectiveness using a Grid scenario, based on a 3D image rendering application. Copyright © 2008 John Wiley & Sons, Ltd.     

无线迁移工作流环境中程序按需移动

作为基于移动计算范型的迁移工作流研究的继续，建立一种无线迁移工作流环境中程序按需移动模型及其实现方法，以支持大型迁移工作流在资源受限移动设备上运行。首先给出了迁移工作流单元模型，它是支持无线环境下迁移工作流的基础，然后给出了迁移工作流按需移动系统架构，讨论了架构中各部分的功能，包括停靠站服务器和工作流管理机的实现机制，分析了通过反射对工作流单元的动态调整。实验表明，无线迁移工作流环境中程序按需移动模型合理，运行可靠，有效支持迁移工作流在无线环境中的应用。     

面向服务集成的工作流模型及其实现方法

针对现有工作流系统集成已有软件服务时存在的两个问题:1)对于业务流程中所集成服务的描述信息不足,无法满足服务集成需要;2)流程定制时可选择节点类型少,节点不具有业务含义,导致其定制过程复杂;提出一种新的工作流模型。首先,通过分析服务集成环境下的实际业务流程确定了模型的三部分信息:结构信息、服务信息和人员信息;其次,将模型中各部分信息与JPDL作了对应说明,表明了模型的完备性;最后,详细介绍了三部分信息的关键要素。实验结果表明,基于35种服务可以快速搭建出满足实际业务需求的48种业务流程。模型中丰富的服务信息为流程运行提供了保障,流程运行正确率100%;流程定制更加简便快捷,流程从定制到运行平均时间小于2 min。通过该模型可以快速地基于已有服务构建新的业务流程,降低了为新需求开发软件的成本。     

工作流事务性研究综述

阐述了工作流中事务性的起源和发展,讨论了事务工作流在建模阶段将业务模型与事务性相结合所采用的主要方法,总结了事务工作流中并发控制机制和采用的各种调度算法,研究了事务工作流的错误恢复机制,概括了广泛应用的补偿机制的研究现状,论述了面向Web服务工作流事务性的特点及相关研究,并展望工作流事务性未来的研究方向.