一种改进的字符串多模式匹配算法

基于字符串匹配的检测方法是入侵检测系统中的一种重要方法。通过分析几种常见的字符串匹配算法（AC、AC_BMH、Sunday等）的基础,提出了一种对AC算法的改进,新算法每一次匹配不成功后都能跳过尽可能多的字符以进行下一轮匹配,使得匹配次数大大减少,从而提高了匹配效率。分析了该算法的性能,并用具体的实验数据给出了几种匹配算法的测试结果。     

入侵检测中一种新的快速字符串匹配算法

基于字符串匹配的检测方法是入侵检测系统中一类很重要的分析方法。文章首先分析了现有的几种准确字符串匹配算法,然后提出了一种新的多模式字符串匹配算法,并且分析了这些算法的复杂性。最后,文章用具体的实验数据来验证这些算法的性能。通过实验可以看出,新算法使得检测速度大大提高,签名容量大大增加。     

一种用于内容过滤和检测的快速多关键词识别算法

基于字符串匹配的检测方法是内容过滤和检测系统中一类很重要的分析方法，首先分析了现有的几种快速字符串匹配算法，然后提出了一种新的多模式字符串匹配算法，并简单分析了算法的复杂性，算法在设计的过程中吸取了BM算法中跳跃的特性，采用了后缀树算法得到了最大跳跃值，采用AC算法的匹配自动机原理从而避免对搜索树内每一个字符的匹配，最后，通过具体的实验数据验证了这些算法的性能，通过实验可以看出，新算法使得检测速度有很大提高，并有效屏蔽了关键词数量的增加对检测速度的影响。     

Sunday字符串匹配算法的效率改进

字符串匹配算法一直是网络监测与审计方面的研究热点。介绍了几种经典的字符串匹配算法,提出了一种基于Sunday算法的改进算法RoSunday算法,该算法主要是在匹配开始前通过一个条件判断语句减少了无意义的匹配次数,提高了算法的执行速度。分析了改进后算法的性能,通过实验结果进一步证明了该算法的有效性。     

一种改进的入侵检测阴性选择免疫算法

针对入侵检测系统阴性选择免疫算法中字符串空间收敛效果差以及运行成本高的缺点,在实验的基础上总结出一种基于计算匹配概率公式的改进算法,该算法与字符串长度无关。基于该算法,对算法中的几个关键参数进行了仿真实验,分析了参数对阴性选择免疫算法的收敛速度、检测失败率等的影响。理论研究与仿真结果均表明,新算法具有更好的收敛速度和检测效果,而且时间空间可调。     

字符串模式匹配算法的改进

字符串模式匹配算法是入侵检测系统中的一种重要算法.通过对两种著名的匹配算法KMP和BM算法以及现有的各种改进算法的分析,提出一种简单实用、易于理解的字符串匹配改进算法.该算法通过每次匹配失败时特殊位置上字符的启发来获得字符串向后移动的可能距离,这个距离由定义的一个统一函数求出,取其中的最大值作为字符串向后移动的实际距离.实验结果表明,该算法能减少模式匹配中字符的比较次数和尝试次数,提高模式匹配的效率.     

字符串模式匹配算法的改进研究

字符串模式匹配算法是入侵检测系统中的一种重要算法。通过对KMP算法和BM算法以及其他改进算法的分析,提出一种简单实用、易于理解的字符串匹配改进算法。实验表明该算法能减少模式匹配中字符的比较次数和尝试次数,提高模式匹配的效率。     

字符串匹配算法比较与分析

对几种典型字符串匹配算法适用范围和结果进行分析,并确定字符串匹配算法得分的接受阈。     

入侵检测多模式匹配算法

基于模式匹配的入侵检测是目前最重要的一种入侵检测方法,面字符串匹配效率是该方法的核心,直接影响检测效率。该文在充分分析BM算法、AC算法及AC_BM算法的基础上提出了一种新的更好搜索步长的多模式匹配算法NMSA,并具体分析了该算法的效率,通过实验数据对比,再次证明NMSA算法具有更好的搜索步长、更好的效率。     

字符串匹配的技术研究与实现

字符串匹配算法在文本挖掘有着重要的应用。本文首先介绍了常见的BF、BM、KMP、QuickSearch等字符串vt配算法,最后通过具体的实验数据给出了几种匹配算法的测试结果,并分析了这几种算法的性能及影响这些性能的因素。     

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.