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大数据环境下的网络主动入侵检测方法研究 总被引：2，自引：0，他引：2
《科技通报》2015,(8)
由于传统网络入侵检测方法检测率低及不能进行在线检测,无法有效实现网络主动入侵检测,提出一种基于马氏距离K均值的大数据环境下网络主动入侵检测方法,分析了马氏距离的评价准则,依据新样本与原样本之间的马氏距离确定是否需开展新的聚类,输出与全部数据样本相应的攻击类别。通过一个由一定数量的支持向量决定的超平对数据进行分类,当SVM分离方法受到约束时,利用核函数将输入数据映射至高维特征空间,采用高斯径向基函数对最小二乘支持向量机分类模型进行建立。通过粒子群优化算法对最小二乘支持向量机参数进行选择。利用种群中个体之间的协作以及信息交换获取最佳方案。仿真实验结果表明,所提方法有很高的的检测效率及精度。 相似文献
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提出了一种将核Fisher鉴别分析特征抽取与多分类支持向量机算法结合的网络入侵检测技术,扩展了二分类支持向量机,利用经过核Fisher鉴别分析特征抽取后的训练数据构造优化的决策树,从而实现支持向量机的多分类.实验结果表明该算法能够提高检测正确率,同时降低训练时间,取得了良好的效果. 相似文献
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在对波段性网络入侵差异化特征进行提取的过程中,会出现入侵差异化特征伪装程度逐渐升高的情况,导致传统的基于敏感性数据挖掘的波段性网络入侵差异化特征提取方法,由于不能有效区分入侵特征与正常特征,无法有效实现波段性网络入侵差异化特征的有效提取,提出一种基于支持向量机的波段性网络入侵差异化特征提取模型,获取不确定入侵中波段性网络节点的差异化特征以及入侵节点,给出两种不确定入侵中波段性网络节点的差异化特征训练数据样本集,通过非线性映射将数据样本集从原空间映射到高维特征空间中,得到高维特征空间中最优线性分类面,采用支持向量机求解该分类面的优化解,使用网格搜索法,通过调整错分惩罚因子与核宽度,分别训练不同的支持向量机,获取泛化能力最强的参数组合,完成入侵中波段性网络节点的差异化特征所对应的数据集的核参数优化和分类,实现波段性网络入侵节点的差异化特征的有效提取。仿真实验结果表明,所提方法具有很高的准确性及有效性。 相似文献
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为去除网络入侵数据集中的冗余和噪声特征,降低数据处理难度和提高检测性能,提出一种基于特征选择和支持向量机的入侵检测方法。该方法采用提出的特征选择算法选取最优特征组合,并以支持向量机为分类器建立模型,应用于入侵检测系统。仿真结果表明,本文方法不仅可以减少特征维数,降低训练和测试时间,还能提高入侵检测的分类准确率。 相似文献
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基于最小二乘支持向量机的数据挖掘应用研究 总被引：6，自引：0，他引：6
随着数据仓库技术、联机分析技术的发展。基于数据库的数据挖掘已成为一种重要的数据处理手段。最小二乘支持向量机作为一种新的机器学习方法。具有全局收敛性和良好的泛化能力。本文将其应用于数据挖掘的分类与预测研究。通过棱函数的选择及参数优化，并结合支持向量机、多层感知器神经网络模型及判别分析方法进行比较研究，证明最小二乘支持向量机作为一种有效的数据挖掘算法具有较高精度。 相似文献
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针对神经网络在轴承工作状态诊断中存在的问题,提出了将最小二乘支持向量机用于轴承的智能诊断。基于轴承故障信息,用最小二乘支持向量机方法建立多类故障分类器,以实现对故障的诊断。仿真证明:小样本情形下,最小二乘支持向量机比神经网络具有更好的识别和诊断准确率。 相似文献
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采集大型火电系统短路数据,并将其转换成为时间序列数据,然后将时间序列数据输入到最小二乘支持分类集中进行训练,训练过程中引入最小二乘支持向量机对布谷鸟算法进行优化,用改进的布谷鸟算法对火电系统的短路位置数据进行距离聚类,从而预测出火电系统的短路地点。仿真结果表明本文算法能更加准确的预测了大型火电系统短路位置的变化态势,提高了大型火电系统短路位置的预测精度。 相似文献
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为了提高模糊支持向量机在入侵检测数据集上的训练效率,提出了一种基于聚类的模糊支持向量机入侵检测算法.该方法可以对训练数据进行剪枝,有效地减少远离分类面的聚类边缘点的数量,同时在分类面附近保持较多的样本点,以靠近判别边界的聚类中心集合作为有效的训练样本集合对模糊支持向量机进行训练,减少了样本的训练时间,提高了算法的效率.实验结果表明该方法提高了模糊支持向量机的训练效率,而且对入侵检测是非常有效的. 相似文献
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熔融指数是高密度聚乙烯生产的主要质量指标,通过对生产数据建模实现对熔融指数的预测,为优化操作提供有力依据,从而提高产品的质量。利用偏最小二乘法提取影响熔融指数的主要因素作为最小二乘支持向量机的输入,克服了自变量间的多重相关性问题;同时也降低了最小二乘支持向量机的输入变量的维数。实验表明,利用偏最小二乘法方法和最小二乘支持向量机方法预测熔融指数精度远高于分别使用这两种方法。 相似文献
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Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
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A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
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Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
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《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
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Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
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《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
17.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献
18.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
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Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
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《中国科学院院刊(英文版)》2014,(3)
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence 相似文献