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1.
对网络入侵信号的准确检测,提高检测概率是保证网络安全的基础,传统检测方法难以实现对较低信噪比下的攻击信号的高效定位和检测,无法有效预测入侵信号的局部特征点,导致重采样,虚警概率和漏检概率较高。提出一种基于局部特征压缩采样的网络入侵信号检测算法,构建低信噪比下网络入侵信号模型,采用多普勒频移模糊搜索对入侵信号进行平滑处理,得到入侵信号的局部特征预测量和测量值,为了使得入侵检测适合线性实时处理过程,提高在低信噪比下的检测性能,采用卡尔曼滤波对结果进行修正,采用局部特征压缩采样判断入侵信号的联合特征,实现了对网络入侵信号的局部特征压缩采样检测。仿真结果表明,该算法检测性能较好,检测概率优于传统算法,展示了较好的应用价值,确保了网络安全。 相似文献
2.
《科技通报》2016,(4)
通过对网络流量的准确预测提高对网络的调控和监测水平,避免网络拥堵,确保网络畅通。传统的网络流量预测算法采用粒子群算法,在处理大规模的流量数据时,容易导致信息发散和易陷入局部极值点,流量预测准确度不高。提出一种基于多标记学习混合差分粒子群进化的网络流量预测算法。构建多分簇的无线网络流量数据传输模型,对网络流量进行时间序列分析,采用粒子群优化算法分别比较网络信息流中的频率波动是否相同,对相同的进行合并,基于自回归移动平均算法,进行粒子群信息链特征优选准则设计,采用多标记学习混合差分粒子群进化算法,把网络流量数据嵌入到内核空间的超球体中,进行离线阶段的网络流量预测优化。仿真结果表明,该算法对网络流量预测的精度较高,误差减少,具有较好的应用价值。 相似文献
3.
在数据库入侵检测的过程中,当数据库规模较大,传统的检测算法只能采集不同区域的攻击或者存在异常的特征,进行分析。缺少数据之间的联系,并且效率较低。提出了一种基于宽幅跳跃关联定位的大型数据库入侵检测算法。新算法通过对数据库特征进行较宽幅度的跳跃检测,组建特征集合。利用宽幅异常特征建立关联检测模型,运用较少的入侵特征点完成大型数据库的入侵特征关联匹配,大幅降低检测时间,通过将全局搜索和局部搜索机制有机地结合,保证检测的准确性。实验结果表明,利用该算法进行数据入侵检测,能够有效提高大型数据库入侵检测的准确性。 相似文献
4.
提出基于半监督混合模型的海量入侵数据检测方法。利用蚁群算法进行入侵数据的特征选择,在结合半监督的混合模型分类方法进行入侵数据的分类,利用混合模型对数据样本空间的聚类分布进行描述,利用数据函数将聚类的信息与分类算法相结合,进行数据分类时对没有标示的数据样本进行考虑,对入侵数据进行检测。克服传统方法存在的弊端,提高了分类器的泛化能力,保证数据分类的效果,提高了入侵数据检测的准确性,完成对大数据环境下网络主动入侵海量数据检测的研究。实验的结果表明,利用本文方法能有效地提高入侵数据检测的准确性。 相似文献
5.
针对传统网络入侵算法在WLAN中的异常检测效率低,提出了一种SVM算法的WLAN入侵检测方法,首先对网络入侵的数据计算信息增益,从原始数据中选取对分类结果影响较大的特征属性,对SVM参数进行优化,最后采用优化的SVM算法对无线网络数据进行检测,得出网络入侵结果.实验结果表明,提出的算法检测正确率高、漏报率与误报率低,具有很好的应用前景. 相似文献
6.
高校微机室接入互联网,这使得高校网络信息系统的安全受到更多关注,尤其是异常入侵检测系统的设计.本文研究了基于SVM的入侵检测系统,针对SVM训练时间长的缺点,提出了一种改进的减少样本点数目的算法.利用Lincoln实验室入侵检测系统评估数据集合对此算法进行测试.结果表明,该算法的训练时间低于传统算法的训练时间,同时成功率接近传统算法,为高校微机室入侵检测系统的设计提供重要参考. 相似文献
7.
提出了一种基于稀松模糊定位算法的网络入侵特征检测算法。新算法通过采集初始网络入侵特征,组建特征集合。利用稀松运动特征匹配算法最大程度上纠正由于特征模糊带来的弊端。保证跟踪匹配过程中,运用较少的入侵特征点完成后期的多个匹配,大幅降低匹配时间,消除匹配误差问题,通过将全局搜索和局部搜索机制有机地结合,保证检测的准确性。实验结果表明,利用本文算法进行入侵检测,能够有效提高检测的准确性。 相似文献
8.
一种网络多次变异信息入侵检测算法 总被引：2，自引：0，他引：2
提出了一种基于变异特征自动机匹配的网络变异信息入侵检测算法.通过提取网络中的异常参数,利用异构数据匹配计算,对发生变异的网络数据特征项进行多次二叉树的建立,分类计算连续变异随机变量服从节点分布,准确对变异特征和非变异特征进行区分.实验表明,该算法提高了网络变异信息入侵检测的准确率,取得了不错的效果. 相似文献
9.
针对传统网络入侵检测方法在实时性响应和入侵行为识别率上存在的不足,本文提出了一种抽取多数类边界样本的入侵检测算法。该算法首先根据中心距离确定网络链接行为中多数类样本的边界样本,然后将多数类样本的边界样本与少数类样本合并构成新的训练集合,最后进行分类学习。该算法有效地降低了类别之间的不平衡度和减少了训练样本数目,具有更好的入侵检测性能。在KDD CUP 99数据集上的仿真实验,充分验证了该算法的有效性。 相似文献
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11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
《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
13.
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
14.
《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
15.
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
16.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
17.
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
18.
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
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
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