无线局域网的通信安全研究

本文介绍了WLAN标准IEEE802.11的安全机制及其面临的威胁,阐述了目前现有的一些基于数据链路层或网络层安全方案的缺陷。在深入研究现有成熟的网络安全技术和大量WLAN应用方式的基础上,并基于技术可行性,提出了将WLAN安全管理和技术结合提高WLAN安全性的策略,并给出了几种典型安全WLAN模型。     

基于WLAN的安全管理需求与安全管理策略

无线局域网(WLAN)摆脱了传统的繁琐综合布线设置,其简易与方便更是被多数单位内部所广泛使用,解决WLAN的安全保密问题就显得尤为突出,针对WLAN安全管理需求问题进行研究和分析,提出了解决WLAN安全管理问题的方法和策略.     

基于IEEE 802.11bWLAN安全技术研究

随着无线局域网(WLAN)技术的迅速发展,其安全问题日益受到人们的关注.由于传输的特殊性,WLAN始终面临严峻的安全考验.无线网络攻击技术的不断翻新,基于IEE 802.11b的攻击技术会越来越多,复杂性将越来越高.所以与有线网路相比,保护WLAN安全的难度要远大于保护有线网络.文中介绍了基于IEEE 802.11b协议下的WLAN可能面临的非法登录、拒接服务、字典攻击等安全威胁,分析了如何提高WLAN下的几种安全机制及802.11协议下的802.11i安全标准.提出了现有无线设备使用中一些可提高WLAN安全性的解决措施,在一定程度上提高了WLAN的安全性.     

基于IEEE802.11b WLAN安全技术研究

随着无线局域网（WLAN）技术的迅速发展,其安全问题日益受到人们的关注。由于传输的特殊性,WLAN始终面临严峻的安全考验。无线网络攻击技术的不断翻新,基于IEE802.11b的攻击技术会越来越多,复杂性将越来越高。所以与有线网路相比,保护WLAN安全的难度要远大于保护有线网络。文中介绍了基于IEEE802.11b协议下的WLAN可能面临的非法登录、拒接服务、字典攻击等安全威胁,分析了如何提高WLAN下的几种安全机制及802.11协议下的802.11i安全标准。提出了现有无线设备使用中一些可提高WLAN安全性的解决措施,在一定程度上提高了WLAN的安全性。     

WLAN安全能指望谁？

随着WLAN(无线局域网)技术的快速发展,WLAN应用的增长速度非常惊人,各级组织在选用WLAN产品时都会担心WLAN的数据传输是否安全,是否能确保数据的完整和安全。而面对众多的WLAN安全方案,我们又能指望谁呢?     

无线局域网的安全体制研究

分析了WLAN的安全问题以及现今常用的一些安全机制,为今后的WLAN安全体制的研究提供参考。     

无线局域网安全分析终端的设计与实现

无线局域网(WLAN)的安全机制是非常脆弱的,因此需要安全分析系统管理WLAN。设计实现了WLAN安全分析系统中的基于嵌入式处理器PowerPC和Linux操作系统的分布式终端。该终端实现了支持安全分析系统中的被动分析和主动分析的接口模块。WLAN数据包的成功捕获和定制发送为接口模块的功能实现提供了依据。     

基于i.MX27的网络摄像机系统设计

针对无线局域网(WLAN)传输中WiFi存在的安全问题,我国提出的WAPI实现了无线局域网(WLAN)中的鉴别和加密机制,提高了无线局域网(WLAN)的安全性。为了进一步对WAPI安全标准的研究和实现,通过对基于i.XM27网络摄像机系统方案设计的改进,提出了支持WAPI安全标准的硬件设计方案。该方案实现了WAPI安全标准在无线局域网(WLAN)中的应用,同时提高了无线局域网(WLAN)的安全问题,最后完成整个网络摄像机系统方案的设计。     

奥运会中WLAN网络的应用与安全防范

本文通过对WLAN安全机制的分析,阐述了WLAN现有机制的隐患及面临的安全风险,并提出了相应的安全防范策略。     

校园WLAN网络的安全研究

校园WLAN网络在校园的全面覆盖为广大师生的学习生活提供了很大的便利,但同时也带来了很多的安全问题。因此对校园WLAN网络的安全问题进行研究就有了重要的意义。文章将会回校园WLAN网络的各种安全问题进行分析,并在此基础上提出完善其安全机制、提升设备性能、对数据进行加密等方式进行解决,本文对校园WLAN网络安全管理工作有着一定的借鉴意义。     

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。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.