基于机器学习的网络入侵检测

在网络入侵检测中,机器学习可以看作是为了通过学习和积累经验提高攻击检测系统的性能而建立的计算机程序。机器学习应用于网络入侵检测,对网络的大量数据进行分析,并通过学习算法自动产生规则,从而使网络具有自动识别攻击的能力。     

基于服务器安全的入侵检测系统在Linux系统上实现

为防止黑客入侵,提出一种在Linux环境下实现网络入侵检测系统的实现方法.此系统由嗅探器、分析器和处理器组成.程序用C语言实现.针对网络层与传输层的IP攻击、ICMP攻击、UDP攻击、TCP攻击特征和数据报做了详细的分析;在网络入侵检测的实现上,使用IP重组预处理和模式匹配相结合的方法,提升了系统检测网络攻击行为的能力,两种检测方法成为有效的互补.     

基于网络入侵检测系统的技术改进

本文从研究入侵检测技术人手，介绍了入侵检测系统的分类；然后分析了基于网络的入侵检测系统（NIDs）的技术方法及其优缺点，指出了当前基于网络的入侵检测系统存在的问题和所面临的挑战．本文在对基于网络的入侵检测系统的研究中，提出将主机知识、网络域知识结合到检测系统中去，解决了检测系统易受插入攻击、躲避攻击的问题．本文还提出了检测子网的概念，根据检测需要将物理子网划分为几个检测子网，可以实现负载的分流和检测任务的专业化分工，负载分流可以彻底解决高速网对网络入侵检测系统的威胁，专业化分工可以大大提高检测引擎的处理速度．     

可入侵容忍的分布式协同入侵检测系统

随着网络环境和应用系统的日益复杂,系统安全对入侵检测提出了新的挑战。本文在分析入侵容忍特性和现有入侵检测方法的基础上,结合协同思想,提出了可入侵容忍的分布式协同入侵检测系统。经实验检测本系统具备一定的入侵容忍能力,通过协同分析发现一些分布式的较为复杂的攻击,对入侵的检测更为细致和全面。     

蜜罐的网络入侵检测系统研究

入侵检测系统是对敌对攻击在适当的时间内进行检测并做出响应的一种工具。它通过收集和分析计算机网络和计算机系统中若干关键点的信息,检查网络或系统中是否存在被攻击的迹象。本文首先介绍蜜罐技术的定义,然后介绍蜜罐技术在网络安全中的作用与地位以及蜜罐系统的分类。最后对罐技入侵检测系统做详细的分析。     

基于数据挖掘的网络入侵检测模型研究

文章简单介绍了传统的入侵检测系统,鉴于现有的网络入侵检测系统(NIDS)存在的误报率高和智能性低等缺点,提出了基于数据挖掘的网络入侵检测系统模型。该模型可以有效检测大规模协同攻击,提高网络入侵检测系统的自适应性和可扩展性。     

基于蜜罐技术的网络入侵检测系统协作模型的研究与实现

针对当前互联网中传统的入侵检测系统无法对未知攻击作出有效判断,而造成信息误报和漏报的问题,从入侵检测和蜜罐的基本特点出发,提出了一种基于蜜罐技术的网络入侵检测系统协作模型,通过引诱黑客入侵,记录入侵过程,研究攻击者所使用的工具、攻击策略和方法等,提取出新的入侵规则,并实时添加到IDS规则库中,以提高IDS检测和识别未知攻击的能力,进一步提升网络的安全性能.     

基于数据挖掘原理的入侵检测系统模型研究

本文介绍了传统的入侵检测系统,鉴于现有的网络入侵检测系统(NIDS)存在的误报率高和智能性低等缺点,提出了基于数据挖掘原理的网络入侵检测系统模型。该模型可以有效检测大规模协同攻击,提高网络入侵检测系统的自适应性和可扩展性,能有效面对各种形式的攻击行为。     

基于管理代理的分布式入侵检测系统设计

将网络管理系统与入侵检测系统相结合,建立基于管理代理的分布式入侵检测系统框架结构。研究管理代理的自治性、协同性以及管理代理间消息通信机制,建立管理代理的功能结构,设计基于遗传算法的调度Agent算法。从网络的各个层次分析管理信息库中与入侵检测有关的管理对象,建立检测规则库。完成分布式多层次结构化的具有自安全性的入侵检测系统的开发,达到管理代理对网络和主机监听目的。研究结果表明:根据攻击的本质特征,使用从管理信息库的统计数据中获取检测规则的方法,能有效实现对隐蔽和复杂攻击的检测。     

基于流量分析的入侵检测系统研究

随着网络技术发展,信息系统的安全性日益成为政府、企业及事业部门越来越关注的重大问题,保障信息系统的安全性已经成为迫切的需要.现有的网络安全系统多采用基于规则入侵检测技术,因而误报率较高;本文根据对边检入侵检测系统测量分析的基础上提出基于流量的边检入侵检测系统,通过量化分析来预测入侵和DDOS攻击,从而保证网络的安全性.     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-