移动自组织网分布式密钥的管理方案

传统的密钥管理方案旨在为现有互联网提供安全通信。移动自组织网是一种新型的无线网络,其主要特点是移动性和能量受限性。因此,传统的密钥管理方案不适用于MANET。针对MANET的特点,已提出了很多高效和安全的密钥管理方案。主要阐述了分布式的移动自组织密钥管理方案,分析了几种典型方法的原理和特性。     

基于中国余数定理的移动自组网签名方案

作为一种新型的无线移动网络,移动自组网（mobile ad hoc network,MANET）的安全是现在主要的研究方向。MANET网络不同于传统的网络,因此需要一些新的安全机制。文章简要介绍了MANET网络体系结构特点所面临的问题和需要达到的安全目标,提出了一种基于中国余数定理的分布式门限签名方案,该方案与MANET的特性非常一致。文章还给出了一个采用RSA公钥系统的数字签名算法。分析表明,这种方案具有较好的计算性能。     

基于簇的移动自组网络信任管理模型

对MANET的特点和它所面临的安全问题进行深入的分析和研究,指出设计合理的信任模型是MANET安全的首要问题。文中首先分析现有的MANET安全解决方案中的不足,进一步对MANET中的信任管理问题进行广泛的讨论。在此基础上提出基于簇的动态信任管理模型（Dtrust）。该模型有效地解决了MANET中的盲目信任问题,最后对该模型下簇的更新方法进行了描述。模拟实验证明了该模型的可行性。     

MANET接入Internet模型的设计与仿真实现

在MANET接入Internet网络中,静态网关提供接入的范围有限,动态网关提供接入的性能不稳定,因此提出动态网关和静态网关协作的MANET接入Internet模型.在此基础上,设计了一种基于该模型的负载均衡路由算法.仿真结果表明,该模型可以提供比较稳定的MANET接入Internet性能,负载均衡算法能够有效提高分组投递率,降低平均传输延迟,减少路由开销以及改善MANET接入Internet网络的整体性能.     

一种MANET认证方案的设计

移动自组织网(MANET)在军事领域、紧急场合等场所备受重视,但安全问题却是MANET的一个弱点。现设计了一种适用于MANET的OTP算法--HOTP,基于此算法设计了一种MANET簇成员的认证方案。分析表明,该方案能够有效地抵制网络监听、穷举攻击等攻击手段,较目前的认证方案[1,2]更为安全有效。     

利用Anycast通信技术实现MANET与IPv6的网络互联

提出一种基于Anycast通信技术实现移动自组织网络(MANET)与IPv6网络的互联方案。该方案中移动结点在不同的移动子网之间进行切换时,利用Anycast通信技术来获取最优的IPv6网关接入点的信息,从而接入Internet。其优点是不需要进行地址的重复检测,也不需要建立隧道机制。对方案进行深入的讨论和分析,并运用NS2仿真软件对数据包接收率等参数进行仿真分析。仿真实验结果表明了该方案的有效性。     

移动Ad hoc网络与Internet互连的QoS保障机制

通过对IntServ／RSVP模型、DiffServ模型、基于IntServ网络的MRSVP的分析和比较,提出了一种新的MANET移动接入QoS保障框架,并在MANET移动接入方法和层次化算法的基础上提出了一种新的资源预留协议MMRSVP。该协议与MRSVP和RSVP相比,实现简单、操作方便,能很好地节省网络资源。     

MANET中基于VSS协议的分域秘密共享安全认证方案

MANET的发展已有很多年,很多相关技术都已非常成熟,但MANET中的安全问题一直都是阻碍其大规模普及应用的一个瓶颈。本文中我们将MANET网络进行分域,各个安全域相对独立进行安全认证和通信加密。引入可验证密钥共享协议(VSS)进行局部域内的密钥共享,并在安全域内进行周期的密钥更新,有效防止移动敌手攻击。在节点通信安全方面应用基于域内终端领导者(EL)的验证方案,有效防止伪终端欺骗,本文的创新点就是将密钥共享、身份认证以及通信安全综合进一个解决方案,有效利用了MANET中有限的网络资源。     

MANET自组织按需认证模型的研究

构建安全可信的MANET 必须考虑到其自身的特性。目前关于MANET 的安全认证研究大多是利用中心认证服务器为用户颁发证书,较少考虑到MANET 自身的自组织特点,很难完成网络的快速部署。结合MANET 的特性,提出一种自组织按需式认证方案。该方案不需要中心认证服务器,充分利用节点自身功能,在完成身份认证的同时具有良好的伸缩性。     

基于负载均衡的移动自组网接入技术研究

在移动自组网（MANET）与Internet互联的网络结构中,针对传统单网关接入的不足,提出一种基于多网关负载均衡的非对称接入技术。该技术由网关发现、网关注册和数据传输三个步骤实现。进行了NS2软件仿真实验,结果表明,该接入算法在网络重负荷的情况下能有效地均衡网络中MANET节点与网关节点的负载,有效延长网络寿命。     

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.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。