基于虚拟组织和移动代理的网格认证机制研究

认证是网格安全的重要组织部分。在网格中，认证的基本场景包括：证书和证书链、身份认证、会话认证。基于虚拟组织和移动代理的网格特色是以虚拟组织为基本管理单元、以移动代理作为网格结点之间重要的交互手段。本论文的主要内容是把网格认证的基本场景内容引入到基于虚拟组织和移劝代理的网格中。基于虚拟组织的网格认证场景主要包括：用户登录虚拟组织、用户获取虚拟组织内部资源、用户获取虚拟组织外部资源。基于移动代理的网格认证场景主要包括：移动代理和移动代理平台之间交互、移动代理之间交互、移动代理迁移。     

支持虚拟组织建立的网格资源协作平台研究

针对基于Internet的学习平台在有效利用教学资源方面存在的问题,采用开放网格服务架构OGSA,建立基于虚拟组织的协作平台.在虚拟组织中,应用或用户能够创建临时服务,资源以网格服务的形式提供给用户或应用.基于OGSA的虚拟组织的建立,为资源共享协作提供了切实可行的解决思路和实施方案.     

动态虚拟组织管理系统设计与实现

网格计算粗粒度的管理方式导致的网格体系僵化带来了诸多不便,成为网格计算在科研领域更深入应用的阻碍。采用虚拟组织的思想,提出了动态虚拟组织管理方案来针对网格计算项目进行细粒度管理。该方案按照虚拟组织的方式管理多个网格计算项目,以虚拟组织成员关系控制用户访问的权限,使得虚拟组织的构成更加灵活。针对Globus网格平台设计了动态虚拟组织管理系统,实际应用表明该系统实现了细粒度的多网格管理,证明了动态虚拟组织管理方案的有效性。     

网格安全互操作及其在滚动轴承生产中的应用

文章通过分析,当前网格平台通常具有网格全局用户身份以及虚拟组织层次结构的公共特征,基于网格平台的主体类型研究网格平台互操作映射策略,并提出一种通用的滚动轴承安全互操作流程。     

一种基于强信任关系的移动安全认证协议

建立强信任关系来实现对移动代理的安全认证方法,是保护移动代理平台在网格环境中免受恶意代理攻击的主要手段。由于网格的异构性以及虚拟组织之间没有信任传递关系,导致移动代理在跨虚拟组织迁移时,存在安全漏洞,所以结合基于D—S理论的资源信任度函数提出动态规划方案是符合网格结构需求的。该方法在移动代理进行迁移时,由移动代理与其所在的网格虚拟组织中的信任调度模块协同工作,完成移动代理的迁移任务,保护了移动代理不遭到恶意平台的攻击。     

高安全度虚拟组织中动态防火墙的设计和实现

网格计算的本质含义是在动态变化的、拥有多个部门或者团体的复杂虚拟组织内,灵活安全地协同实现资源共享和问题求解[1]。建立安全、稳定、可扩充的虚拟组织是整个网格技术的基础。本文分析了在网格环境下组建高安全度虚拟组织时传统防火墙体制遇到的问题,设计了旨在保障虚拟组织高度安全性的新型动态防火墙模型,并给出了在Linux平台下这种防火墙的实现方法。     

滚动轴承生产中的网格安全相互操作

网格计算为地理分布资源的聚合以及大规模计算问题的解决提供了技术途径,滚动轴承的生产是基于网格平台构建,并通过这些平台管理着滚动轴承的资源/服务,为了聚合不同网格平台管理滚动轴承的资源/服务,需要实现异构网格平台的互操作。由于不同网格平台的安全机制不同,安全互操作是网格互操作中需要解决的一个关键问题。通过分析,当前网格平台通常具有网格全局用户身份以及虚拟组织层次结构的公共特征,基于网格平台的主体类型研究网格平台互操作映射策略,并提出一种通用的滚动轴承安全互操作流程。     

基于网格虚拟组织的分层分布式密钥协议

分析了网格计算系统中面向虚拟组织的动态组密钥管理需求，讨论了基于虚拟组织成员选择环境的“虚拟组织4层结构”和“成员加入策略”，给出了分层分布式密钥协议，避免在密钥的集中式分发与管理模式中，出现单点失败的情况，并具有了层次结构的优点。     

网格资源发现中资源虚拟组织构建方法研究

怎样合理有效地组织网格资源是网格资源发现的关键问题.对网格环境下资源的组织方式进行了研究,提出了网格资源结点动态自组织算法,通过该算法能够将网格资源结点合理有效地组织成具有资源类型的网格资源虚拟组织;提出了资源虚拟组织大小划分的原则,有效地解决了网格资源发现系统中资源虚拟组织与系统规模之间的矛盾,通过仿真试验验证了该方法的有效性.     

基于网格服务的数据发布系统

网格的核心任务是管理分布在Internet广域环境中的各种类型的软硬件资源，为基于Internet的分布式应用提供一个统一的、虚拟的共享资源的计算平台。如何将数据库资源并入现有的网格架构，满足更加广泛的网格应用的数据访问需求，已经成为一项亟待解决的课题。文章提出了一套网格环境中的数据发布系统的设计方案，以网格服务的形式封装对数据库的访问，实现跨越异构网络环境、异构操作系统环境和异构数据库平台的统一访问模式，从而将数据库资源加入到网格环境中。     

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.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

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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