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Privilege Flow Oriented Intrusion Detection Based on Hidden Semi-MarkovModel 被引量:2
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作者 ZHONG An-ming 1, JIA Chun-fu 1,21.College of Information Technology and Sciences, Nankai University, Tianjin 300071,China 2.State Key Laboratory of Information Security, Institute of Software of Chinese Academy of Science, Beijing 100039,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期137-141,共5页
A privilege flow oriented intrusion detection method based on HSMM (Hidden semi-Markov Model) is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS (Intrusi... A privilege flow oriented intrusion detection method based on HSMM (Hidden semi-Markov Model) is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS (Intrusion Detection System). Using the dataset of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost. 展开更多
关键词 key words intrusion detection privilege flow model HSMM
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A Novel Immune System Model and Its Application to Network Intrusion Detection 被引量:2
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作者 LingJun CaoYang +1 位作者 YinJian-hua HuangTian-xi 《Wuhan University Journal of Natural Sciences》 CAS 2003年第02A期393-398,共6页
Based on analyzing the techniques and architecture of existing network Intrusion Detection System (IDS), and probing into the fundament of Immune System (IS), a novel immune model is presented and applied to network I... Based on analyzing the techniques and architecture of existing network Intrusion Detection System (IDS), and probing into the fundament of Immune System (IS), a novel immune model is presented and applied to network IDS, which is helpful to design an effective IDS. Besides, this paper suggests a scheme to represent the self profile of network. And an automated self profile extraction algorithm is provided to extract self profile from packets. The experimental results prove validity of the scheme and algorithm, which is the foundation of the immune model. 展开更多
关键词 key words network Intrusion detection System 5 Immune System self profile automated self profile extraction algorithm
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Methods for Increasing Creditability of Anomaly Detection System
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作者 YANQiao 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期79-82,共4页
Based on Bayes' theorem we point out that the false positive rate must be lower than the intrusion base rate in order to make the Alarm Credibility Probability of the intrusion detection system exceed 50%. We pres... Based on Bayes' theorem we point out that the false positive rate must be lower than the intrusion base rate in order to make the Alarm Credibility Probability of the intrusion detection system exceed 50%. We present the methods that have been used in our developing intrusion detection system AIIDS (artificial immune intrusion detection systems) to increase the creditability of anomaly detection system. These methods include increasing the regularities of the system call trace by use of Hidden Markov Model (HMM), making every antibody or detector has finite lifetime, offering the detector a co-stimulate signal to illustrate whether there is damage in the system according to the integrity, confidentiality, or availability of the system resource. 展开更多
关键词 key words intrusion detection creditability false positive rate
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Skew Detection for Binary Document Images Using Mathematical Morphyology
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作者 Xu Hong bo 1, Tian Yan 2 1. Department of Physics, Central China Normal University, Wuhan 430079, Hubei, China 2. Institute of Pattern Recognition and Artifical Intelligence, Huazhong University of Science and Technology, Wuhan 430074,Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期338-340,共3页
The input document images with skew can be a serious problem in the optical character recognition system. A method is proposed for skew detection in binary document images using mathematic morphology. The basic proces... The input document images with skew can be a serious problem in the optical character recognition system. A method is proposed for skew detection in binary document images using mathematic morphology. The basic process of our approach consists of three steps: Firstly, a dilation operation is applied to the binary image; Secondly, the dilated image is thinned; Finally, the skew angle is detected using the Hough transform. The proposed approach with high precision can detect skew with large angle (?90δ-90Δ). The experimental result shows this method is applicable and efficient. 展开更多
关键词 key words skew detection DILATION THINNING Hough transform
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KEY WORDS INDEX(volume 26)
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《中国现代应用药学》 CAS CSCD 北大核心 2009年第12期I0023-I0035,共13页
关键词 中国现代应用药学杂志 卷第 TEST rate volume 26 key words INDEX
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一种改进MVI-CFAR检测器的性能分析 被引量:4
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作者 杜海明 马洪 《计算机工程与科学》 CSCD 北大核心 2012年第11期163-168,共6页
VI-CFAR检测器在均匀环境和非均匀环境下均具有较强的自适应性,但若前后两个参考滑窗均存在干扰目标时,VI-CFAR检测性能急剧下降。为克服该问题,本文采用有序统计平均CFAR和有序统计选小CFAR来替代VI-CFAR中最小选择CFAR。所提出的算法... VI-CFAR检测器在均匀环境和非均匀环境下均具有较强的自适应性,但若前后两个参考滑窗均存在干扰目标时,VI-CFAR检测性能急剧下降。为克服该问题,本文采用有序统计平均CFAR和有序统计选小CFAR来替代VI-CFAR中最小选择CFAR。所提出的算法不但解决了干扰目标位置随机分布的问题,还解决了当其中一个滑窗的干扰目标数超过最大容限时检测性能下降的问题。在参考滑窗中干扰目标个数与扰噪比均不相同的情况下,分析了统计量VI的变化,有助于评估和设计VI-CFAR类检测器在多目标环境下抗干扰目标的最大容限。仿真结果表明,该改进算法提高了VI-CFAR在多目标环境下的鲁棒性,与其他改进算法相比,其排序处理时间降低一倍。 展开更多
关键词 恒虚警率检测 可变标识 OSVI IVI MVI 非均匀背景 均匀背景
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基于网页正文主题和摘要的网页去重算法 被引量:5
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作者 周小平 黄家裕 +2 位作者 刘连芳 梁一平 申文明 《广西科学院学报》 2009年第4期251-253,共3页
针对元搜索返回的网页内容相同,别名差异很大的重复网页,提出基于网页正文主题和摘要的网页去重算法,并通过实验对算法进行有效性验证。该算法首先对各成员搜索引擎返回来的网页标题进行有关处理,提取出网页的主题信息,然后对摘要进行分... 针对元搜索返回的网页内容相同,别名差异很大的重复网页,提出基于网页正文主题和摘要的网页去重算法,并通过实验对算法进行有效性验证。该算法首先对各成员搜索引擎返回来的网页标题进行有关处理,提取出网页的主题信息,然后对摘要进行分词,再计算摘要的相似度,二者结合能更好地现出文章摘要的内容,实现网页去重。该算法有效,并且比基于传统特征码的算法有明显的优势,更接近人工统计结果。 展开更多
关键词 去重 网页 分词 相似度 元搜索
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检验检疫“三率”指标体系及其综合评价研究 被引量:5
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作者 李延辉 潘家琰 +2 位作者 颜杰 方树春 邓贵波 《检验检疫学刊》 2013年第4期24-28,31,共6页
论述了检验检疫"三率"(检出率、覆盖率、优惠关税利用率)指标体系的研究建立,并运用统计学综合评价方法和数值方法理论研究提出了检验检疫综合检出率和"三率"综合评价指标及其数学计算模型;根据"三率"综... 论述了检验检疫"三率"(检出率、覆盖率、优惠关税利用率)指标体系的研究建立,并运用统计学综合评价方法和数值方法理论研究提出了检验检疫综合检出率和"三率"综合评价指标及其数学计算模型;根据"三率"综合评价体系纳入业务统计分析系统研发后的计算实例,进一步阐述了本研究提出的检验检疫综合检出率和"三率"综合评价指标对检验检疫把关服务进行量化评价的实践运用(用于绩效考核)。 展开更多
关键词 检出率 覆盖率 优惠关税利用率 “三率”指标 综合检出率 综合评价
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China’s financial conundrum and global imbalances 被引量:7
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作者 Ronald Mckinnon Gunther Schnabl 《China Economist》 2009年第4期65-77,共13页
China’s financial conundrum arises from two sources: (1) its large trade (saving) surplus results in a currency mismatch because it is an immature creditor that cannot lend in its own currency. Instead foreign curren... China’s financial conundrum arises from two sources: (1) its large trade (saving) surplus results in a currency mismatch because it is an immature creditor that cannot lend in its own currency. Instead foreign currency claims (largely dollars) build up within domestic financial institutions. And (2) economists – both American and Chinese – mistakenly attribute the surpluses to an undervalued renminbi. To placate the United States, the result is a gradual appreciation of the renminbi against the dollar of 6% or more per year. This predictable appreciation since 2004, and the fall in US interest rates since mid 2007, not only attracts hot money inflows but inhibits private capital outflows from financing China’s huge trade surplus. This one-way bet in the foreign exchange markets can no longer be offset by relatively low interest rates in China compared to the United States, as had been the case in 2005-06. Thus, the People’s Bank of China (PBOC) now must intervene heavily to prevent the renminbi from ratcheting upwards – and so becomes the country’s sole international financial intermediary. Despite massive efforts by the PBOC to sterilize the monetary consequences of the reserve buildup, inflation in China is increasing, with excess liquidity that spills over into the world economy. China has been transformed from a deflationary force on American and European price levels into an inflationary one. Because of the currency mismatch, floating the RMB is neither feasible nor desirable – and a higher RMB would not reduce China’s trade surplus. Instead, monetary control and normal private-sector finance for the trade surplus require a return to a credibly fixed nominal yuan/dollar rate similar to that which existed between 1995 and 2004. But for any newly reset yuan/dollar rate to be credible as a monetary anchor, foreign "China bashing" to get the RMB up must end. Currency stabilization would allow the PBOC to regain monetary control and quash inflation. Only then can the Chinese government take decisive steps to reduce the trade (saving) surplus by tax cuts, increased social expenditures, and higher dividend payouts. But as long as the economy remains overheated, the government hesitates to take these trade-surplus-reduction measures because of their near-term inflationary consequences. 展开更多
关键词 China FINANCE RMB EXCHANGE rate GLOBAL Imbalances key words: China FINANCE RMB EXCHANGE rate GLOBAL imbalances
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Population Characteristics and Future Population Countermeasures for the Studied Counties in Tibet, China 被引量:1
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作者 LIUJian PENGChuan-zhong +1 位作者 Xiang-mei ZHONGXiang-hao 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期739-744,共6页
Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of th... Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of the population in this region. The analyses show that since the 3nl population census, total population, average age and total birth rate have all changed considerably: ① Total population has grown, fast, with most counties' annual average growth rate of more than 10. ② In terms of the region's average age, in 2000 the age in the 18 counties is younger than 30 years old. ③ Compared with the 3nl population census, labor force by the 5th census is much younger. ④ Countermeasures are proposed to control population by controlling birth rate as the result of the local resident's quality improvement by education. 展开更多
关键词 key words average age total birth rate dependency index population development countermeasures One River and Two Tributaries region TIBET
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One Method for Improving RAID5 Performance
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作者 Chen Qiong, Zhang Jiang-ling, Feng Dan School of Computer Science and Engineering, Huazhong University of Science and T echnology, Wuhan 430074, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第3期289-292,共4页
As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It ... As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It is a general method to improve RAID5 performance by using cache. However, it often happens that the data is not hit in cache, in this case, the RAID5 performance also will be very poor. The method based on combination of disk I/O operations has been proposed for impriving the I/O response time through reducing the number of low-level operations. According to theoretic analysis and experimental test, we find that RAID5 access time and data transfer rate could be largely improved than conventional method. 展开更多
关键词 key words RAID I/O combination access time response time data transfer rate
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一种变信噪比条件下的恒虚警野值检测方法 被引量:1
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作者 汝小虎 柳征 +1 位作者 姜文利 黄知涛 《航空学报》 EI CAS CSCD 北大核心 2016年第7期2259-2268,共10页
野值检测又称异常值检测,是模式识别、机器智能和知识发现等领域经常面临的一个问题。当出现环境失配,数据信噪比(SNR)发生变化时,测试样本和训练样本所含噪声会有不同方差,以往的野值检测方法在虚警控制方面将会失效。针对这一问题,提... 野值检测又称异常值检测,是模式识别、机器智能和知识发现等领域经常面临的一个问题。当出现环境失配,数据信噪比(SNR)发生变化时,测试样本和训练样本所含噪声会有不同方差,以往的野值检测方法在虚警控制方面将会失效。针对这一问题,提出一种基于归一化残差(NR)的野值检测方法。该方法首先根据所需虚警概率和噪声方差变化情况确定野值检测门限,其次基于训练样本计算待考查模式的NR值,再比较NR值与检测门限的相对大小,从而判断待考查模式是否为野值。这一方法所依赖的检测门限对所需虚警率和噪声方差变化具有适应能力,因此可以在变信噪比条件下实现恒虚警(CFAR)野值检测。仿真实验验证了所提方法在虚警控制和野值检测方面的优越性能。 展开更多
关键词 模式识别 野值检测 恒虚警 虚警概率 归-化残差
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