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1.
网页服务器用来传递或处理各种信息,网络攻击手法日新月异,造成诸多攻击手法可以很容易地被实现,多数的入侵检测系统以入侵特征规则作为检测基础,仅能对已知的弱点做有效的检测;提出一个适用于网页服务器的应用型入侵检测模块,将检测模块直接嵌入于网页服务器中,以“异常行为检测”和“错误行为检测”的办法,确认攻击类型,有效地预防新型攻击行为与检测已知攻击事件,对提高系统的安全性有重要作用。 相似文献
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Aiming at the problems of the low detection rate of traditional intrusion detection systems and the long training and detection time of intrusion detection systems based on deep learning,an adaptive binning feature selection algorithm using the information gain is proposed,which is combined with LightGBM to design a fast network intrusion detection system.First,the original data set is preprocessed to standardize the data;then the redundant features and noise in the original data are removed through the adaptive binning feature selection algorithm,and the original high-dimensional data are reduced to the low-dimensional data,thereby improving the accuracy of the system and reducing the training and detection time;finally,LightGBM is used for model training on the training set selected by the characteristics to train an intrusion detection system that can detect attack traffic.Through verification on the NSL-KDD data set,the proposed feature selection algorithm only takes 27.35 seconds in feature selection,which is 96.68% lower than that by the traditional algorithm.The designed intrusion detection system has an accuracy rate of 93.32% on the test set,and its training time is low.Compared with the existing network intrusion detection system,the accuracy rate of the proposed system is higher,and its model training speed is faster. 相似文献
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试验及实际运行经验表明,接地装置冲击特性是影响输电线路耐雷性能的重要因素.笔者以土壤电离过程中的动态、分布式土壤参数为基础,对典型接地装置建立冲击特性有限元模型;根据仿真计算结果与模拟试验结果从电磁场角度分析了典型接地装置的冲击散流机理及散流规律;同时定量计算了冲击电流作用下土壤参数及注入电流参数对土壤电离区域体积的影响规律,在此基础上分析了土壤电离对典型接地装置接地电阻、跨步电压、接触电压等接地参数的影响.结果表明,土壤电离现象对冲击散流特性和冲击接地参数的影响在高幅值注入电流、高电阻率地区更明显.该研究结果可为输电线路冲击接地降阻新措施的提出提供理论支持. 相似文献
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As a representative polyoxamide, poly(hexamethylene oxamide) (PA62) has good comprehensive performance. However, the high Tm (330°C) creates an obstacle for processing. To improve the processability of PA62, poly(hexamethylene terephthalate/hexamethylene oxamide) alternating copolyamide (alt-PA6T/62) was synthesized by hexamethylene diamine-terminated 6T6-diamine and dibutyl oxalate via solution/solid state polycondensation. Random copolyamide (ran-PA6T/62) was also synthesized for comparison. The structure and properties of the copolymer were analyzed by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Wide-angle X-ray diffraction (WAXD) and the saturated water absorption test. The NMR results confirm the alternating structure of alt-PA6T/62. The DSC and TGA results demonstrate that the novel alternating copolyamide alt-PA6T/62 (Tm = 321°C, T5 = 420°C) exhibited better thermal properties than those of ran-PA6T/62 (Tm = 294°C, T5 = 412°C). The saturated water absorption of alt-PA6T/62 was found to be 3.2 wt%. These results revealed that the novel alt-PA6T/62 had an alternating sequence distribution, showed a high melting point as well as good processability and thermal stability, and possessed low saturated water absorption and excellent dimensional stability. 相似文献
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根据全息干涉法对板材轧制成形中的变形进行分析,假设三种典型轧制板的截面形状模型,计算了纵向非均匀应变分布,给出了其所产生的残余应力及其失稳起皱时的临界参数计算公式。与实测结果比较,变形的最大误差为11%。 相似文献
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将椭圆曲线密码体制和三叉树引入到群组密钥协商中,提出了一种基于椭圆曲线和三叉树的群组密钥协商协议,由于无需向群组所有其它成员广播消息,其计算开销和通信开销均只有O(nlog3 n)。采用了用初始协商的密钥值加密随机数并产生杂凑值的方法使三叉树内部结点间也能进行安全的协商;当有群组成员变动时,通过发起者更新其随机数来提供协议的前向保密性和后向保密性,因此该方案适合于较大规模的动态群组。 相似文献
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Hong Wien Chen Tung Shou Yin Zhaoxia Luo Bin Ma Yuanbo 《Multimedia Tools and Applications》2017,76(3):3761-3782
Multimedia Tools and Applications - A novel data hiding method for Absolute Moment Block Truncation Coding (AMBTC) compressed image based on quantization level modification is proposed. Blocks of... 相似文献
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基于ATM网络的捷变加密系统设计 总被引:1,自引:1,他引:0
捷变的加密系统可以根据应用的不同而动态地对密码参数进行切换.文章从ATM网络的基本特性出发,阐述了ATM网络捷变加密系统设计中应注意的有关问题,给出了捷变加密系统的总体结构,并对其各个模块作了深入探讨. 相似文献