面向服务软件中基于着色Petri网的异常处理模型

面向服务软件异常处理的开发工作量大且程序逻辑复杂。若只在设计阶段后期或是编码阶段考虑异常处理功能的开发,则可能由于没有充分、完整、系统地考虑待处理的异常而严重影响软件整体可靠性。针对面向服务软件中异常处理机制的特点,提出一种基于着色Petri网的异常处理模型。通过对异常处理组成元素和异常处理模式分别进行形式化描述,可提供可重用的异常处理模型元素。设计者根据面向服务软件中异常处理的实际需求,使用异常处理模式连接异常处理组成元素,形成一个完整的异常处理模型。利用该模型可以精确描述面向服务软件中异常处理总体方案,便于辅助设计人员检测异常处理设计方案中的缺陷。     

SOA研究进展

近年来,面向服务的体系结构(SOA)逐渐成为软件工程领域的研究热点,它在企业信息系统集成、分布式软件系统开发方面都具有明显的优势,也是应对企业灵活多变的业务需求挑战的关键技术.总结了面向服务的体系结构技术发展过程及其主要研究方向,介绍了当前面向服务的体系结构的研究进展,应用实践.并且在分析了典型的面向服务的体系结构之后,给出了面向服务的体系结构的定义.通过分析和总结面向服务的体系结构研究领域的主要研究方向和内容,提出了面向服务的体系结构研究的思路.探讨了当前面向服务的体系结构研究中的不足之处,并预测了面向服务的体系结构进一步的研究方向.     

面向服务软件异常处理过程的可终止性验证

大规模面向服务软件运行环境的动态性和不确定性使其异常处理逻辑复杂度高,导致异常处理过程的可终止性验证异常困难。而异常处理过程的可终止性是确保其正确性的重要基础,如果异常处理过程不能终止将导致面向服务软件无法正常运行。目前缺乏异常处理过程的可终止性验证方法,从而无法保证异常处理达到预期的目标。基于着色Petri网(colored Petri net,CPN)提出了一种面向服务软件异常处理过程的可终止性验证方法。该方法建立了包括正常流程和异常处理逻辑的异常层次CPN模型(hierarchy CPN model for exception handling,HCPN4EH)。基于此模型验证了异常处理过程的可终止性。通过一个实例说明了该方法的可行性和有效性。得到的可终止性验证结果可为进一步分析异常处理过程的正确性提供基础。     

一种容错的面向服务体系结构描述语言

针对如何构建具有容错能力的面向服务软件体系结构的科学问题,提出了一种新型的支持异常处理的面向服务体系结构描述语言SOADL-EH。该语言不仅具备表示面向服务软件体系结构的建模能力,还提供了异常处理服务、异常连接件及异常配置等语言成分,清晰地将面向服务软件体系结构层的异常处理逻辑从正常业务逻辑中分离出来,弥补了已有的面向服务体系结构描述语言在建模异常处理能力方面的不足。     

基于程序分析的代码查询技术

策略描述语言是策略驱动的面向服务流程异常处理方法的基础和前提。针对目前已有策略语言在描述面向服务流程异常处理逻辑方面的不足,提出了一种新的面向服务流程异常处理的策略描述语言WS-Policy4BPEH。它在Web服务策略框架的基础上,扩展了ECA对规则执行影响的描述,定义了多种面向服务流程的异常处理动作模式,能够详细、准确地描述异常及异常处理方式、返回方式和传播方式。WS-Policy4BPEH采用XML作为元语言,因此具有良好的可扩展性。     

基于SOAP的Web服务中的异常处理方法

在构建基于SOAP协议的Web服务过程中,针对Web服务中异常处理存在的问题,提出了一种Web服务中的异常处理新方法:集成代理技术和服务器端加入异常监测.这种方法直接将Web服务的异常消息转换为SOAP消息,通过代理转发到客户端,使用户更好地了解Web服务当前的运行状态,从而提高软件的健壮性.     

基于软件网络的服务自动分类和推荐方法研究

服务的分类和推荐方法对于服务管理和组合都具有重要意义.文中利用服务组合历史,从面向服务软件的结构角度研究了服务分类和推荐方法:提出面向服务软件的软件网络模型,并用于抽象面向服务软件的拓扑结构;利用复杂网络社区发现算法对软件网络进行聚类,从而实现服务的自动分类;利用软件网络描述服务之间的可组合关系及其强度,并基于服务的使...     

面向服务应用中服务可用性及其引发的异常处理研究

面向服务应用倡导以松耦合的方式构建开放、动态的网络应用，系统对异常的检测和处理也由此面临许多新的挑战．分析了构建和运行面向服务应用的主要阶段中要面对的异常问题，重点探讨了在应用执行过程中由于服务的可用性问题引发的异常，并提出了一种基于案例匹配的异常处理方法．该方法应用到了奥运公众信息服务平台原型系统FLAME2008中，对其实际效果进行了评价．     

一种基于CPN的BPEL异常处理逻辑的开发方法

针对WS-BPEL在面向服务软件异常处理方面不够完善的问题,提出了一种基于着色Petri网描述的BPEL异常处理逻辑开发方法。该方法利用着色Petri网(CPN)形式化地描述BPEL的异常处理机制,建立BPEL的异常处理CPN模型,指导对BPEL的异常处理逻辑开发,并依据此建模思想,提出了一个BPEL的异常处理CPN模型的转换工具,用以实现将异常处理的BPEL着色Petri网模型转换成对应的带异常处理的BPEL代码。该工具可在输入的原始的没有异常处理功能的BPEL代码基础上,通过动态地添加BPEL的异常处理语言成份,形成带有异常处理功能的BPEL流程。最后通过引入供应商流程案例,阐述了该方法的具体使用过程。     

面向服务软件中异常处理模块重要性的仿真分析方法

基于蒙特卡洛方法,提出异常处理模块重要性的影响因子,其中包括异常处理模块所对应的保护区的重要性以及异常处理模块自身的稳态故障率.基于贝叶斯理论,计算保护区的重要性;运用马尔可夫链的遍历性计算异常处理模块的稳态故障率.试图提出一种面向服务软件中异常处理模块重要性的定量分析方法,设计人员可以根据分析结果对重要度高的异常处理模块给予更多的关注.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate