入侵

This article analyses the actual reality of network security and briefly intruduces a few of aggressive measures which threaten the safety of network. From these we can see, the passive ways such as firewall and anti-virus software to combat network attack can not meet the increasingly needs of network accessing .As a result, an intrusion detection system must be established to differentiate between the legal accessing and inbreaking attack. That is intrusion detection.

本文首先分析了目前的网络安全现状，简单介绍了几种威胁网络安全的攻击手段，从中可以看出通过防火墙和杀毒工具等软件，被动地防御网络攻击已经不能满足日益增加的网络访问量了，因此必须变被动为主动，对到达的网络访问内容进行审核，来判断是合法的访问还是入侵攻击，这种审核就是入侵检测。

in pearl river delta region,water environmental contamination featured big amount and mixed types and centralization of pollutant discharge with latent combined pollutants,striding boundary pollution,severe municipal pollution,the trend of regional pollution being extended from cities to rural area,infall of salty tide in recent years.as a result,the unwatered complexion was hastened due to bad water quality.the factors of water environmental contamination were analyzed as the natural factors including especial hydrographic net distributed pattern,water body runoff characteristic,water resource distributive regional difference,infall of ocean tide,and so forth; the artificial factors as inconsequence of economic development mode and distribution of industry and cities planning,lagging environmental infrastructure,indifferency of environmental consciousness,dissonance of economic development and environmental protection.

珠江三角洲地区水环境污染特点表现为：污染物排放量大、类型杂且集中，潜在复合污染出现，跨界污染突出，城市污染依然严重，并呈现出从城市向农村蔓延的区域性污染趋势，加上近几年咸潮入侵加剧，使区域水质型缺水的局面更趋紧张。造成这种污染局面的因素：一方面受控于区域内特殊的河网分布格局，水体径流特征、水资源分配的地区性差异以及海潮入侵等自然因素；另一方面也反映了区域经济发展模式，工业布局和城市规划不尽合理，环境基础设施滞后，环境意识淡薄，经济发展与环境保护不协调等人为因素所致。

Calculation of the minimum flow rate to prevent mainstream from ingressing into cavity by numerical simulation is a contribution to the design of the cooling system of disc cavity. It is meaningful to the subsequent investigation of mainstream ingression both experimentally and numerically.

通过数值方法计算出外流存在下阻止主流燃气入侵的最小无量纲流量，这对于涡轮盘冷却系统的设计是一个贡献，对于后续的旋转盘腔系统主流入侵问题的实验及数值研究有一定意义。

The development and applications of SSR molecular markers in identification,hybridization and introgression,bottleneck effect in the invasion process of invasive insects were discussed in this paper.

本文概述了SSR分子标记在入侵昆虫来源鉴定、杂交和基因渗透、瓶颈效应等方面的应用进展，并对其在入侵生物学中的应用前景进行了展望。

With the further development of intrusion detection technology, it provides a new way to study the network security.

入侵检测技术的进一步发展，给网络安全的研究带来了新的途径，入侵检测系统已成为必不可少的重要手段。

Therefore, it is very important to study mechanisms underlying successful invasion of alien plants.

因此，研究外来植物成功入侵的内在机制是入侵生态学中的关键问题之一。

System incentive and alternation of attacker's strategies are not taken into full consideration in current intrusion response research. An intrusion response model (intrusion response based on attack graph, IRAG) based on the attack graph is proposed to solve this problem.

针对当前入侵响应工作中存在的不能充分考虑系统的收益，以及不能充分考虑攻击者策略变化因素等问题，提出了一种基于攻击图的入侵响应IRAG(intrusion response based on attack graph)模型。

The Snort is a typical Net Intrusion Detection System, and some of design principle and characteristics of which is the base of most popular mercantile Intrusion Detection System.

Snort系统是一个典型的网络入侵检测系统，其若干设计原理和实现特点，是目前多数商用入侵检测系统的研发基石。

An integrity-protecting method based on Merkle hash tree is presented. This method can check the integrity of security rules stored in database. Its space cost and time cost is modest. A prototype of DIPS is implemented.

本文研究了数据库入侵防护系统的实现技术，测试了原型系统对数据库系统性能的影响以及原型系统在入侵防护方面的表现，并详细的分析和比较了测试结果。

We do research on the transitions between states of network protocol,the protocol misusage detection model based on Markov chain,the framework of the IDS technology and protocol anormity after we discuss the current technology. The main research contents of this paper include: research on transitions between states of network protocol and session process, protocol misuage and the anomaly detection model based on Markov chain, the research of intrusion detection framework, more accurately model based on the characteristic of the network traffic and so on.

在分析了现有入侵检测系统的基础上，本文围绕典型网络协议状态转换、基于马尔可夫链的检测模型、入侵检测技术框架、以及协议异常等几个方面展开深入研究，主要工作内容包括：典型网络协议转换状态的分析和会话过程的研究；基于马尔可夫链的网络异常检测模型；分布式的检测架构；针对网络流量特征而提出了精确的检测模型等。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。