An automatic subdigraph renovation plan for failure recovery of composite semantic Web services

A Web service-based system never fulfills a user＇s goal unless a failure recovery approach exists. It is inevitable that several Web services may either perish or fail before or during transactions. The completion of a composite process relies on the smooth execution of all constituent Web services. A mediator acts as an intermediary between providers and consumers to monitor the execution of these services. If a service fails, the mediator has to recover the whole composite process or else jeopardize achieving the intended goals. The atomic replacement of a perished Web service usually does not apply because the process of locating a matched Web service is unreliable. Even the system cannot depend on the replacement of the dead service with a com- posite service. In this paper, we propose an automatic renova- tion plan for failure recovery of composite semantic services based on an approach of subdigraph replacement. A replacement subdigraph is posed in lieu of an original subdigraph, which includes the failed service. The replacement is done in two separate phases, ofltine and online, to make the recovery faster. The ofitine phase foresees all possible subdigraphs, pre-calculates them, and ranks several possible replacements. The online phase compensates the unwanted effects and executes the replacement subdigraph in lieu of the original subdigraph. We have evaluated our approach during an experiment and have found that we could recover more than half of the simulated failures. These achievements show a significant improvement compared to current approaches     

鄱阳湖水利枢纽工程关键技术研究

本文针对鄱阳湖水利枢纽工程修建后将发挥的作用和可能产生的影响,采用现场调研、实测资料分析和数学模型计算等研究手段,从鄱阳湖流域水资源演变趋势及开发利用状况,三峡水库运用对长江中下游河道冲淤变化及江湖关系的影响,枢纽工程对水资源、防洪、湖区水环境和鱼类的影响,枢纽工程合适的下闸蓄水时期和蓄水位,工程闸门型式及鱼道建设等方面进行了研究,试图为鄱阳湖水利枢纽工程项目立项和规划设计提供科技支撑。     

一种基于服务覆盖网络的业务运行平台

针对分布式业务的动态性和可扩展性需求,设计并实现了业务运行平台BEPSON（Business Execution Platform Based On Service Overlay Network）。该平台基于服务覆盖网络,采用分层架构,提出并实现了具有QoS保证的动态服务发现算法以及分布式的执行策略。最后,通过实例验证了平台的有效性和灵活性。     

面向最终用户编程的服务虚拟化模型

为了解决面向最终用户编程问题,提出了一种基于动态语义的服务虚拟化模型。该模型以SOA思想理论为基础,采用面向服务计算和Web服务技术,结合本体服务描述语言和描述逻辑,建立服务虚拟化模型,从而实现面向最终用户编程。该模型有效地提高了模型的查全率和查准率,能够在一定程度上解决软件危机。     

浅谈IT服务的可用性设计方法

2011年新版ISO／IEC20000的发布,为IT服务管理的实施提供了参照标准。本文根据ISO／IEC 20000：2011版中的IT服务可用性要求,提出面向客户服务级别需求设计和实现IT服务的可用性,并指出可用性设计是实现高质量IT服务的有效途径。     

软件类专业校企合作共建实训基地研究

从国家发展时工程型人才需求出发,分析了工程应用型人才培养的必要性,以及校企共建实训基地在工程应用型人才培养方面所起的作用.结合高校软件类专业工程应用型人才培养的现状、特点和要求,以及软件类专业实训基地的特点,提出了当前软件类专业校企合作实训基地的模式,探讨了建立校企合作实训基地必须要考虑和解决的问题.     

基于Web服务的可视化作战想定生成系统设计与实现

设计一个基于Web服务的可视化作战想定生成系统,该系统实现了与具体仿真系统的松散耦合,能够跨越C4ISR系统、作战仿真应用、想定生成系统等仿真系统底层数据结构的异构性,快速重用分布仿真系统的想定资源,提高想定开发效率,并使仿真系统之间的互操作更加灵活。     

A Web services-based framework for building componentized digital libraries

We present a new Web services-based framework for building componentized digital libraries (DLs). We particularly demonstrate how traditional RDBMS technology can be easily deployed to support several common digital library services. Configuration and customization of the framework to build specialized systems is supported by a wizard-like tool which is based on a generic metamodel for DLs. Such a tool implements a workflow process that segments the DL design tasks into well-defined steps and drives the designer along these steps. Both the framework and the configuration tool are evaluated in terms of several performance and usability criteria. Our experimental evaluation demonstrates the feasibility and superior performance of our framework, as well as the effectiveness of the wizard tool for setting up DLs.     

Determinants of accepting wireless mobile data services in China

Data services via wireless networks and mobile devices have experienced rapid growth worldwide. We investigated the factors influencing adoption of wireless mobile data services (WMDS) in China and tested our model for explaining adoption intentions there. We argued that individuals form their intention to adopt WMDS under the influence of wireless mobile technology, the social environment, personal innovativeness of IT, trust awareness, and the facilitating conditions. We examined the simultaneous effects of these five influences on beliefs in the context of wireless Internet data services via mobile phones. Survey data were collected from 1432 participants in several metro cities across China. The findings suggest that WMDS adoption intention in China is determined by consumers’ perceived usefulness and perceived ease of use of WMDS. Theoretical and practical implications are included in our paper.     

A survey on the history of transaction management: from flat to grid transactions

Transactions have been around since the Seventies to provide reliable information processing in automated information systems. Originally developed for simple ‘debit-credit’ style database operations in centralized systems, they have moved into much more complex application domains including aspects like distribution, process-orientation and loose coupling. The amount of published research work on transactions is huge and a number of overview papers and books already exist. A concise historic analysis providing an overview of the various phases of development of transaction models and mechanisms in the context of growing complexity of application domains is still missing, however. To fill this gap, this paper presents a historic overview of transaction models organized in several ‘transaction management eras’, thereby investigating numerous transaction models ranging from the classical flat transactions, via advanced and workflow transactions to the Web Services and Grid transaction models. The key concepts and techniques with respect to transaction management are investigated. Placing well-known research efforts in historical perspective reveals specific trends and developments in the area of transaction management. As such, this paper provides a comprehensive, structured overview of developments in the area.