改进攻击树的恶意代码检测方法

为了解决传统攻击树模型在恶意代码检测中存在行为差异性描述不准确、危害量化不合理的问题,提出一种将攻击树结构进行改造、构建攻击树文本图的改进攻击树检测方法,并设计了危害权值算法,从而可以更好地描述和判断恶意代码的攻击行为,引入云检测技术构建检测系统对算法进行验证.实验结果表明,该算法较传统算法对恶意代码及其变种的检测有明显的提高.     

基于行为特征的恶意代码检测方法

本文分析总结了恶意代码的行为特征,提出了一种分析API序列来检测恶意代码的方法.该方法在传统攻击树模型中添加了时间、参数调用等语义相关信息,提升了攻击树模型对代码行为的描述能力,并对恶意代码中常见的危险API调用序列进行建模.通过虚拟执行的方法获取代码的API调用序列.并将这些序列与扩展模型进行模式匹配.发现代码中的恶意行为,计算其威胁指数,进而检测代码是否具有恶意性.     

一种基于并发命题投影时序逻辑模型检测的入侵检测方法

基于投影时序逻辑模型检测的入侵检测方法具有描述网络入侵者分段攻击的能力,然而对并发攻击仍无能为力,因为该逻辑无法直接描述并发。针对此问题,在该逻辑的基础上定义了一种新的并发算子,并给出基于并发投影时序逻辑模型检测的入侵检测方法。对复杂攻击实例的检测表明,新方法可有效提高对并发攻击的检测能力。     

一种基于行为的Android系统资源访问控制方案

Android Permission机制作为一种粗粒度的访问控制机制,不能有效地阻断应用程序对系统资源的滥用,使得Android恶意代码容易借此实施攻击.因此,在Android Permission机制的基础上提出了基于行为的Android系统资源访问控制方案,对应用程序访问系统资源的行为进行规范,防止系统资源被滥用而破坏系统安全.该方案利用TLCK(temporal logic of causal knowledge)时序逻辑描述语言,为与系统安全相关的关键系统资源访问定义安全的行为模式,并对应用程序执行过程中的行为进行动态监视,通过比对应用程序的动态行为模式和资源访问要求的安全行为模式,实施访问控制.与基于恶意行为特征的恶意代码检测方案相比,安全的资源访问行为模式更容易定义,并且能够应对未知攻击.最后,针对占Android恶意代码比例最高的短信(short message service,SMS)攻击,对系统中的SMS资源进行细粒度、基于行为的访问控制实现,并通过验证实验证明,该方案具有良好的效能和性能表现.     

一种基于投影时序逻辑模型检测的入侵检测方法

基于时序逻辑模型检测的入侵检测技术降低了误用检测的漏报率,然而却几乎不能描述并发攻击和分段攻击,因而对这些复杂的攻击模式漏报率仍很高。本文针对该问题,提出了一种基于投影时序逻辑模型检测的入侵检测方法。对若干复杂攻击实例的检测表明,新方法可有效降低对并发攻击和分段攻击的漏报率。     

基于TLA的NS安全协议分析及检测

行为时序逻辑是一种组合了时序逻辑与行为逻辑来对并发系统进行描述与验证的逻辑,在描述并发转移系统中,行为时序逻辑通过引入行动和行为的概念,使得系统和属性可用同一种行为时序逻辑来表示。本文首先介绍行为时序逻辑的语法、语义及简单推理规则;然后以典型的NS公开密钥协议为例,对其进行形式化分析,建立了入侵者参加的简化模型。通过对模型进行FSM建模,转化为TLA+描述的规约系统,然后对其进行TLC检测,发现其存在中间人的重放攻击。     

基于扩展攻击树的文件安全度评估研究

在深入研究恶意代码行为特征基础上,本文通过分析传统恶意代码检测模型的缺陷,建立了基于扩展攻击树的文件安全度评估模型,综合节点自身属性值与节点间相互关系,提出了一种基于行为的动态恶意代码行为分析检测方法。该方法能够有效评估文件的安全度,对包含未知恶意代码的文件也具有一定的检测能力。     

基于模型检测的程序恶意行为识别方法

利用恶意代码所具有的相同或相似的行为特征,提出一种基于模型检测技术的程序恶意行为识别方法。通过对二进制可执行文件进行反汇编,构建程序控制流图,使用Kripke结构对程序建模,利用线性时序逻辑描述典型的恶意行为,采用模型检测器识别程序是否具有恶意行为,并在程序控制流图上对该恶意行为进行标注。实验结果表明,与常用的杀毒软件相比,该方法能更有效地发现程序中的恶意行为。     

基于时序逻辑的加密协议分析

形式化方法由于其精炼，简洁和无二义性，逐步成为分析加密协议的一条可靠和准确的途径，但是加密协议的形式化分析研究目前还不够深入，至今仍没有统一的加密协议验证体系，针对这一现状，该文从加密协议可能面临的最强大的攻击着手，提出了一种基于时序逻辑的加密协议描述方法，在该模型下，对协议行为，入侵者行为，安全需求等特性的描述均用时序逻辑公式表达，从而利用现有的统一的时空逻辑框架分析密码协议的性质，特别地，作者描述和检测了一个系统入侵者不能用任何代数和逻辑的办法获得消息的实例，通过对比，作者认为该方法具有形式化程度较高的特点。     

基于相识度的恶意代码检测

特征码的识别方法仅能识别已知的恶意代码,并未解决恶意代码的判别问题.当前基于行为的扫描和启发式扫描也只是关注恶意代码的单个的危险行为点,误报率很高.侧重挖掘行为之间的关系,采用矩阵将待测代码的行为及行为之间的关系进行描述、测量,由此提出一种基于相识度的恶意代码检测方法.相识度是系统对待测代码的熟悉程度.根据相识度的大小来判断待测代码是否为恶意代码,相识度越大,待测代码是恶意代码的可能性就越小.在此基础上,提出了相应的恶意代码检测算法,通过实例验证了该方法的有效性.     

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     

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.     

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。