桌面虚拟化安全访问控制架构的设计与实现

为解决桌面虚拟化环境中虚拟桌面共享数据中心服务器并将用户数据集中存储带来的安全隐患,对原有虚拟桌面结构进行改进,并结合虚拟安全域、hypervisor安全增强技术和安全标签技术,实现了全新的桌面虚拟化安全访问控制架构。将用户虚拟桌面中不同安全等级的应用程序运行在不同的虚拟机中,将虚拟桌面中不同安全等级的虚拟机和用户数据划分到不同的虚拟安全域并下发相应的安全策略,实现了虚拟桌面的通信隔离和对存储资源的访问控制。     

基于GPU透传的图形工作站共享技术研究

介绍基于虚拟桌面和GPU透传技术实现多用户共享图形工作站的主要设计思想和实现框架,对图形工作站共享技术的应用方案和性能进行阐述。提出将虚拟桌面技术应用于图形工作站,为用户创建各自独立的虚拟桌面,分享图形工作站的CPU、内存、硬盘等物理资源。同时,借助GPU透传技术,将图形工作站的物理显卡分别透传到各个虚拟桌面,使图形工作站可供与显卡数目相同的用户共享使用。测试结果表明,通过该技术用户可以快速地连接到自己的虚拟桌面运行图形密集型应用程序,图形处理将交付给透传过来的物理显卡执行,能够确保图形设计所需要的性能。     

基于位置信息的流式移动应用推送系统的研究

目前与位置相关的移动应用越来越多,传统应用分发模式中,用户需要手动对应用进行搜索、下载、安装以及卸载,不利于提升用户使用应用服务的体验。设计并实现了基于位置信息的流式移动应用推送系统,该系统中服务器利用移动终端位置信息将相关应用解析、安装,并推送到移动终端显示,移动终端根据用户的选择从服务器流式加载应用。该系统使得用户在切换位置时,不用下载、安装即可使用和当前位置相关的应用服务。实验表明,和传统应用分发模式相比,在3G网络环境下可以减少64.37%的应用获取时延,在4G网络环境下可以减少74.49%的应用获取时延。     

感觉Netware5（下）

Netware5的新一代管理工具Z．E．N．worksNetware5的管理和Netware4．11一样，可以通过NetwareAdministrator完成大部分管理任务，但Ne。are5提供了新一代的基于NDS的桌面管理工具Z．E．N．works（用户零努力网络），它充分发挥Novell目录服务的强大功能，提供了软件分发、桌面管理和工作站维护等功能，使得对各种版本Wi。d。WS操作系统的工作站的管理更加方便。在Z．E．N．works中包含很多策略，每个策略代表对工作站进行管理的某一方面的规则。如用户系统策略规定用户在使用桌面应用程序时有哪些限制，远程控制策略可以设置工作…     

让Windows XP一变四

Linux有着强大的桌面管理工具——虚拟桌面，而且可以在2～9个虚拟桌面间定制。虚拟桌面极大地方便了应用程序的管理。难道Windows用户就不能享受到虚拟桌面的方便吗？No，其实Windows也可以的。     

用nView来玩虚拟桌面

如今,nView技术除了支持显卡双头输出和多显示器之外,对于单显示器的用户还增加了创建和管理虚拟桌面的功能。 nView最多允许用户创建多达32个虚拟桌面,并且能够方便地通过多种途径在桌面间切换,将不同桌面的应用程序窗口进行交换。最重要的方便之处便是用nView来创建虚拟桌面     

VB.NET编程实现图片浏览功能

VB.NET语言主要用来构建在.NET Framework上运行的各种安全、可靠的应用程序。使用VB.NET,可以创建各种类型的应用程序和服务。相对于字符界面的控制台应用程序,基于Windows窗体的桌面应用程序可以提供丰富的用户交互界面,从而实现各种复杂功能的应用程序。     

基于播存结构的雾架构内容协同分发机制

雾计算是一种将云服务推向用户边缘的计算范型,其主要采用用户被动拉取内容的方式来加速内容分发,缺乏主动推送能力。因此,提出利用具备主动推送力度强的播存结构来辅助雾架构以实现内容的主动推送。在此基础上,针对边缘内容协同分发,提出一种基于软件定义的内容协同分发机制,具体包括多粒度协同存储机制、软件定义策略和域内多节点协同策略。最后利用原型系统进行实验测试与结果分析,结果验证该机制能够高效减少用户请求时延,提升用户体验。     

云环境下实时消息推送服务构建研究

随着移动互联网技术的发展,各类消息纵横交错,人们在获取关联信息时常感到无从选择。传统的消息获取,用户需要主动拉取网络存储的消息,此种方式获取消息的效率极其低下,会产生众多与用户无关的消息。消息推送需要用户不停地拉取刷新,属于被动推送。随着云技术的发展,消息推送技术逐步转变为云推送,告别了单一服务器推送的模式。对现有各类消息推送技术进行研究和分析,针对传统基于主题订阅模式的消息推送服务只能对应单一移动端通信的不足,提出了云实验环境下实现实时消息推送服务的构建方案,设计了消息推送服务(PushWeb)的运行框架,运用H5技术中的WebSocket技术实现了管理平台和移动客户端应用程序,并将其部署在阿里云中,经测试在良好的网络环境下能够将消息实时准确地推送至移动端。     

桌面虚拟化加速普及

桌面虚拟化解决方案通过将桌面作为托管服务交付来降低IT成本并加强控制,为用户提供所需的访问灵活性,同时加强IT部门对桌面、应用程序和数据的控制。这可以大大降低成本,提高企业在市场中的反应速度,满足法规遵从性准则．并确保所有桌面和应用程序都保持最新状态。从虚拟桌面所能承载的功能来看,它具有广泛的适用性并为企业的IT管理和业务拓展带来了深远的影响。     

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