基于转换概率及RO结构的硬件木马检测

针对硬件木马倾向于在电路低转换概率节点插入的问题,提出了一种在这些节点处构建环形振荡器（RO）结构的方法来检测硬件木马。该方法首先计算电路节点的转换概率并挑选出低于转换概率阈值的节点,然后在挑选出的节点处构建RO结构,通过RO延时的变化进行木马的检测。实验以ISCAS’85基准电路为基础,并在Spartan6 FPGA开发板实现。实验结果表明,在可接受的面积和功耗开销下,可以检测到仅有一到两个门的小型木马电路,弥补了旁路信号分析法检测小型木马的不足。     

针对电路关键路径的硬件木马监测与防护

随着半导体产业的快速发展,硬件木马已经对集成电路的可靠性和安全性带来了巨大的隐患。现有的研究表明,电路的关键路径易受到硬件木马的攻击。针对电路的关键路径提出了预防硬件木马插入的实时监测方案。根据电路的拓扑逻辑顺序计算电路各个路径的延时,选取电路延时最大的路径作为电路的关键路径,计算关键路径上所有节点的转换概率,优先选择关键路径上低于特定阈值的节点进行监测器设计。同只检测电路主输出的逻辑测试法相比,充分考虑了关键路径上硬件木马的激活不改变主输出的情况。实验结果表明,该方案在最多增加24.32%的面积开销下,可以有效地预防和监测硬件木马在ISCAS85电路关键路径的插入。     

基于概率签名的硬件木马检测技术

针对集成电路芯片被植入硬件木马后带来的安全问题,提出一种基于概率签名的硬件木马检测技术。通过逻辑功能检测,采用随机算法构建芯片电路（布尔函数）的概率签名,作为唯一的识别符模板,当被测电路的签名与模板不匹配时发出告警。设计全加器和AES加密2款电路,植入常见硬件木马并进行攻击实验,对这2种电路的原始电路以及植入硬件木马后电路的概率签名是否发生改变进行理论分析与研究。采用统计学参数估计法在FPGA平台进行实验,结果表明,该概率签名技术能检测出一般规模组合逻辑电路中植入的硬件木马,置信度达到95％。     

激光激活异步累加器硬件木马研究

随着集成电路设计制造的全球化,芯片存在被植入硬件木马的隐患.目前的硬件木马检测方法中,逻辑测试激活硬件木马的概率较低,侧信道检测受电路工艺偏差、硬件木马面积影响较大.本文提出基于激光注入的硬件木马检测方法,通过诱发数据翻转主动激活硬件木马触发逻辑,同时可以定位硬件木马触发逻辑的物理位置.采用1064 nm皮秒脉冲激光成功激活了基于FPGA的异步累加器型硬件木马.研究表明对于具有逻辑触发结构的硬件木马,激光注入方法与硬件木马的触发条件无关.通过设计高覆盖率的注入方式,能够高概率的激活硬件木马.     

扫描电压对硬件木马检测影响分析

硬件木马是一种微小而隐蔽的恶意电路,它隐藏在目标芯片中,在一定条件下实施对目标芯片输入输出节点状态或功能的恶意修改。随着集成电路设计生产全球化的不断加剧,芯片设计与生产环节的分离增加了芯片被植入硬件木马的可能性,给芯片的安全性与可靠性带来了极大的威胁。因此,如何检测被测芯片是否含有硬件木马,确保集成电路芯片安全变得日益重要。文章基于40nm 工艺库下,对高级加密标准 AES 算法的网表中设计植入相对于无木马AES 电路大小为2.7%的信息窃取型硬件木马,并与无木马 AES 电路作为 Golden 参考模型进行对比,通过分析 PVT（工艺、电压、温度）参数中不同工作电压对电路旁路功耗信息影响的规律,发现由工作电压抖动而引起的功耗噪声可以淹没由硬件木马的植入而引入功耗信息,进而降低硬件木马检测效率,在此基础上文章提出一种基于随机扫描电压叠加的硬件木马旁路功耗信息的显化方法,规避了在常规硬件木马检测时电压波动对硬件木马的检测影响,实现对硬件木马的检测。     

基于模型检测的硬件木马检测技术研究

硬件木马对原始电路的恶意篡改,已成为集成电路面临的核心安全威胁.为了保障集成电路的安全可信,研究人员提出了诸多硬件木马检测方法.其中,模型检测作为一种形式化验证方法,在设计阶段可有效检测出硬件木马.首先,阐述了模型检测的工作原理和应用流程;其次,介绍了基于模型检测的硬件木马检测技术的研究进展;最后,指出了当前该技术所面...     

基于多信号特征融合的硬件木马识别技术

针对现有基于信号特征的硬件木马检测方法中存在木马特征集单一、检测精度低和普适性差等问题,提出一种基于多信号特征融合的硬件木马识别方法.通过分析硬件木马的隐藏性,建立触发节点植入与载荷节点植入的硬件木马隐藏性模型,构造低静态翻转率、低动态翻转率、低组合0可控性、低组合1可控性和低组合可观察性的硬件木马特征集,利用KNN算法建立硬件木马检测模型.实验结果表明,该方法达到了98.23％ 的木马信号平均识别率,与文献[3]和文献[15]相比,分别提高了16.30％ 和10.24％,大幅提升了木马检测能力.     

基于特征匹配的IP软核硬件木马检测

集成电路设计过程中引入的非受控第三方IP软核较容易被植入硬件木马,以往的功能测试方法较难实现全覆盖检测。为此,分析硬件木马结构及其在IP软核中的实现特征,提出一种基于硬件木马特征匹配的检测方法。给出特征识别流程,构建基于Trust-Hub硬件木马的特征库,在AES算法的RTL,级描述中设计3种不同功能类型的硬件木马电路进行分析。实例结果表明,利用提出的特征匹配方法并结合目标载体特征分析,可在冗余代码不高于10%的精度下实现硬件木马的有效识别。     

基于稀有度与逻辑加密的硬件木马防护方法

为了进一步加强基于逻辑加密的硬件木马防护技术,针对稀有节点筛选与基于逻辑加密的硬件木马防护方法,提出基于稀有度的指标检测潜在的触发器节点。结合树形加密结构提出改进型逻辑加密技术,从而能够减小木马节点的误判率,有效防止硬件木马插入并提高对可满足性攻击的防护能力。通过对典型电路的实验分析,该方法可以有效提高对潜在触发器节点的筛选效率,在保证消除稀有节点的前提下进一步提升安全性。     

基于木马特征风险敏感的硬件木马检测方法

针对现有硬件木马检测方法中存在的木马检出率偏低问题，提出一种基于木马特征风险敏感的门级硬件木马检测方法。通过分析木马电路的结构特征和信号特征，构建11维硬件木马特征向量；提出了基于BorderlineSMOTE的硬件木马特征扩展算法，有效扩充了训练数据集中的木马样本信息；基于PSO智能寻优算法优化SVM模型参数，建立了木马特征风险敏感分类模型。该方法基于Trust-Hub木马库中的17个基准电路展开实验验证，其中16个基准电路的平均真阳率（TPR）达到100%，平均真阴率（TNR）高达99.04%，与现有的其他检测方法相比，大幅提升了硬件木马检出率。     

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.