决策树与神经网络结合的入侵检测系统模型研究

入侵检测系统是保证网络信息安全的有力手段,文中提出一种结合决策树和神经网络的入侵检测系统框架。决策树分类方法把数据集划分为正常数据和入侵数据,并作为训练集分别用神经网络进行训练,改善了系统的检测精度并提高了对未知数据的检测能力。离线训练后的系统可以实现网络数据的实时检测,通过实验证明了此系统很好的检测效果和自适应能力。     

基于模糊决策树的入侵检测规则生成技术

针对计算机免疫系统模型GECISM中的类MC Agent,利用模糊决策树Fuzzy-Id3算法并使用应用程序中的系统调用作为数据集构造决策树,从而生成计算机免疫系统中的入侵检测规则,并与C4.5算法生成规则进行了对比分析,利用Fuzzy-Id3算法方法生成的规则对未知数据集进行分类有较低的误报率和漏报率.     

基于决策树的协同网络入侵检测

由于不同网络协议有不同的属性值,不同的数据集可被用来检测网络入侵.该文提出了一种基于决策树的协同网络入侵检测模型,该模型是由多个代理组成,每个代理针对不同的网络数据协议类型(TCP/UDP/ICMP)分别履行检测,且它们又通过协同构成一个整体检测体系.最后用KDD CUP 99数据进行实验,验证了该方法检测入侵行为的有效性.     

基于物联网的粮情监控系统中入侵检测研究

在基于物联网的粮情监控系统中,传统入侵检测方法很难准确实时地从海量数据提取特征信息来识别网络攻击,使系统容易遭受安全问题,从而破坏数据的完整性,因此,提出一种基于深度信念网络的交替决策树入侵检测(DBNADT)方法。该方法利用深度信念网络进行无监督地特征学习,通过预训练将原始数据特征降维,利用权值微调算法获得数据的最优低维表示;然后采用交替决策树分类器对各种异常网络入侵数据进行识别。结果表明,DBN-ADT方法在攻击行为的识别准确率上比支持向量机(SVM)和逻辑回归(LR)分别提高了7.24%和8.25%,在检测时间上分别缩短了约1/2和2/5。DBN-ADT方法具有更高的检测准确率和实时性。     

入侵检测规则动态生成研究

在入侵检测研究领域中,提高检测模型的检测率并降低误报率是一个重要的研究课题.本文提出了一种针对网络入侵检测事务流的实时动态规则生成方法.该方法解决了当前主流关联规则生成算法应用到入侵检测过程中存在的多遍扫描、大量无效规则和频繁集产生等问题.实验结果表明,文中所提出的方法在规则动态生成和对网络异常情况的检测方面都显示出比较好的性能,相对Snort入侵检测系统,平均提高10%左右的检测精度,克服了Snort系统在异常检测方面的局部缺陷.     

入侵检测系统规则的挖掘

针对基于网络的入侵检测系统Snort,提出了一种新颖的规则挖掘方法.这种方法希望帮助Snort入侵检测系统,自动从检测的攻击数据中生成误用检测规则,实现自动检测最新攻击和异常攻击的能力.为了达到这样的功能,设计了一个规则挖掘模块,它能够应用数据挖掘技术从收集的检测攻击包中提出新的攻击规则,并且转化到Snort系统的检测...     

基于决策树的入侵检测的实现

决策树是分类的常用方法.文章针对一个局域网上模拟的入侵检测问题,描述了对利用决策树方法学习的一种优化实现.并且对怎样处理缺失数据、连续属性的离散化、怎样剪枝以及分类法的准确率评估及提高等关键技术进行了研究.实验证明,该方法可为入侵检测系统生成有效的决策树.     

基于主成分分析和决策树的入侵检测方法

特征选择算法能够更好地提高入侵检测系统的检测速度和检测效果,消除冗余数据并减轻噪音特征.结合特征选择算法的优势,提出一种基于主成分分析(PCA)与决策树(C4.5)的入侵检测方法,进而构建出轻量级的入侵检测系统.通过在KDD1999数据集上对该方法进行详细的实验验证,证明该方法一方面确保系统有较高的检测率与较低误报率,另一方面能够比较显著地提高系统的训练时间与测试时间.同时,通过比较实验发现此方法在训练时间、测试时间、检测率、误报率上的效果也优于GA-SVM方法.     

一种基于可拓距的特征变换方法及其在网络入侵检测中的应用

作为识别攻击或异常行为以保护网络安全的重要步骤之一,网络入侵检测常常与数据挖掘或机器学习技术结合应用.如今,随着网络数据的爆炸性增长,传统的入侵检测技术面临着海量数据检测处理的问题,现有入侵检测系统往往难以同时满足实时性和有效性的需求.本文尝试将可拓学中的可拓距概念引入网络入侵检测研究中,提出了一种基于可拓距的特征变换方法,将数据点的原特征映射为簇外中心距和簇内可拓距这两大部分,根据原始数据多维特征生成新的特征,以达到特征降维的目的,旨在同时满足网络入侵检测系统的实时性和有效性的需求.本文使用KDD CUP 99作为仿真数据集测试所提出的基于可拓距的方法在网络入侵检测特征变换中的应用效果.实验结果表明,较之传统的KNN算法,基于可拓距的方法明显地减少了检测时间,而同时其检测率的下降可以控制在1%之内,具有较好的时效性优势.     

基于二次训练技术的入侵检测方法研究

提出了一个基于二次训练技术的网络入侵检测模型,不但可以从整体上提高入侵检测系统的检测性能,而且对于低频率、高危害攻击类型的检测性能有着更加显著的提升.该模型首先利用PCA算法提取数据集中的重要特征,然后使用二次训练技术训练分类器构建网络入侵检测模型.实验中分别使用决策树、朴素贝叶斯和KNN 3个经典分类算法构建了基于二次训练技术的入侵检测模型,并在著名的KDDCup99数据集上进行了实验.结果表明本文的入侵检测模型可以有效地提高入侵检测系统的性能,尤其是对于低频率攻击类型的检测性能有明显的提升.      

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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