基于主动网络技术的可编程移动IP网络及其应用

针对目前情况，基于主动网络技术提出了一种可编程移动IP网络，该网络体系结构可以快速创建和部署新的移动IP服务和协议，这样的网络结构大大加快了移动应用服务的市场化进程。基于可编程移动IP网络体系结构开发了一种主动式移动IP协议，从而证实了可编程移动IP网络在服务创建上的高效性。     

基于NS-2的微移动IP协议仿真分析

微移动IP协议能在域内提供快速、无缝切换控制，是对移动IP协议的补充。分析了三种主要的微移动IP协议：层次型移动IP、蜂窝IP和HAWAII，并在NS-2中建立一个通用的仿真分析模型，对三种微移动协议的主要性能进行分析和比较。     

移动支持协议切换性能研究

切换是移动支持协议研究的重要内容,其性能好坏对移动网络的性能和服务质量提供具有至关重要的影响.在合适的网络模型和切换模型的基础上,通过理论分析和数值仿真的方法对各类移动支持协议(包括移动IP与微观移动协议以及不同的微观移动协议)的切换性能进行了深入的研究和比较.结果表明,切换性能受无线网络参数和移动支持协议的路径更新算法两个因素影响;采用微观移动协议时的切换性能好于只使用移动IP时的情形;在所有微观移动协议中,MIP-RR和MMP协议中的路径更新算法切换性能最佳.     

微移动IP协议中移动管理技术的研究现状

微观移动IP协议在域内提供快速、无缝的切换控制并支持IP寻呼功能,改进了系统性能,完善和补充了传统移动IP协议。本文将分别讨论几种典型的微观移动IP协议:蜂窝IP、Hawaii和分层移动IP,并通过建立通用微观移动IP模型对他们的工作原理进行分析,并对性能进行比较。最后展望了微观移动IP协议与基本移动IP协议结合起来在无线网络中的应用.     

一种基于分层代理的移动IP安全注册协议

在移动IP应用环境中，由于无线信道的开放特性和节点的移动性会给网络安全带来许多新的问题。而移动IP的注册则是安全管理的前提与基础，是移动IP协议能够继续执行的关键。本文提出了一种基于分层代理的移动IP安全注册协议，以解决移动IP安全注册的难题，提高移动性网络的安全性能．同时减少认证注册的开销。     

无线移动环境下的组播路由协议

介绍了在两种典型的无线移动环境下的组播路由协议——移动IP网络和AdHoc网络，比较了它们的特性和性能。在无线移动环境下实现组播路由协议是一件很复杂的工作，比起固定网络下的组播实现，它的路由模式、转发算法、可靠性、安全性等的实现都更为困难。最后对该领域的前景进行了展望。     

一种基于移动IP的RSVP协议扩展方案

目前的RSVP协议是针对固定网络的特性设计的，不适于移动无线网络。本文提出了一种RSVP协议的扩展方案，使其适用于移动IP网络，减小了发生拥塞的可能；最后通过模拟验证了其性能。 [     

移动IP技术及其路由优化

随着网络通信技术的发展，移动计算机用户对Internet移动接入的需求急剧增长，IETF设计了移动IP协议，使Internet上的移动接入成为可能，该文介绍了移动IP的工作原理、目前移动IP路由方面的问题及其改进方案。     

基于NS-2的微移动IP协议仿真分析

微移动IP协议能在域内提供快速、无缝切换控制,是对移动IP协议的补充。分析了三种主要的微移动IP协议:层次型移动IP、蜂窝IP和HAWAII,并在NS-2中建立一个通用的仿真分析模型,对三种微移动协议的主要性能进行分析和比较。     

基于移动IP的反向隧道功能的研究与实现

针对现有移动IP协议功能实现的局限性，研究了移动IP涉及的主要实体在移动过程中的行为，提出了一个基于移动IP的反向隧道功能实现的方法。该方法利用Linux提供的隧道机制，在Linux全用户空问中创建了一个能突破路由器入口过滤的移动节点反向隧道的功能函数，初步实现了移动节点离开家乡网络后的通信功能，完善了移动IP协议功能。     

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.     

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.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

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