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information-Theoretic Analysis for the Difficulty of Extracting Hidden information

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Information-Theoretic Analysis for the Difficulty of Extract...

The 1st chinese Conference on Trusted Computing and information security

作者： ZHANG Wei-ming, LI Shi-qu, CAO Jia, LIU Jiu-fen Department of information Research, information Engineering university,Zhengzhou 450002, Henan, China {3. key laboratory of information security, (graduate School of the chinese academy sciences), beijing 10003., China

＜正＞ The difficulty of extracting hidden information, which is essentially a kind of secrecy, is analyzed by information-theoretic method. The relations between key rate, message rate, hiding capacity and difficulty of extraction are studied in the terms of unicity distance of stego-key, and the theoretic conclusion is used to analyze the actual extracting attack on Least Significant Bit（LSB） steganographic algorithms.

关键词： information hiding steganography extracting attack difficulty of extraction unicity distance

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随机性序列的典型纠偏方法及分析

计算机科学 2003年第1期30卷 131-132页

作者：杨柱吕述望苏桂平中国科学院研究生院信息安全国家重点实验室北京100039

According to the definition of random experimentation and the demand of random sequence in cryptogra-phy, three typical methods to rectify the deviation of random sequence are given below. We discussed the characterso... 详细信息

关键词：随机性序列纠偏方法密码学随机发生器概率统计

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一种高效和可扩展的OCSP系统

通信学报 2003年第11期24卷 93-99页

作者：周永彬卿斯汉季庆光张振峰中国科学院软件研究所中国科学院信息安全技术工程研究中心北京100080 信息安全国家重点实验室北京100080

证书状态查询是PKI中的一个关键问题,OCSP是解决这个问题的一种重要机制。本文分析了OCSP协议的技术细节,并在此基础上设计了一种高效的、可扩展的OCSP系统。文中对该系统的关键技术和其自身的安全性问题进行了详细的论述。最后,给出了... 详细信息

证书状态查询是PKI中的一个关键问题,OCSP是解决这个问题的一种重要机制。本文分析了OCSP协议的技术细节,并在此基础上设计了一种高效的、可扩展的OCSP系统。文中对该系统的关键技术和其自身的安全性问题进行了详细的论述。最后,给出了关于OCSP机制的一些未决问题以及某些思考。

关键词：公钥基础设施 OCSP系统证书状态查询认证中心

Privilege Flow Oriented Intrusion Detection Based on Hidden Semi-Markov Model

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Privilege Flow Oriented Intrusion Detection Based on Hidden ...

The 1st chinese Conference on Trusted Computing and information security

作者： ZHONG An-ming, JIA Chun-fu College of information Technology and sciences. Nankai university. Tianjin 3.0071 .China {3. key laboratory of information security, Institute of Software of chinese academy of Science, beijing 10003.,China

＜正＞ 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 data set of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost.

关键词： intrusion detection privilege flow model HSMM

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半Bent函数的密码学特性

山东大学学报（理学版） 2002年第6期37卷 480-483,512页

作者：秦静赵亚群山东大学数学与系统科学学院济南250100 中科院研究生院信息安全国家重点实验室北京100080

给出了半bent函数的定义与Walsh谱特征 ,并讨论了其密码学特性 .

关键词： bent函数半bent函数 Walsh循环谱自相关函数扩散准则

Spectral Feature Analysis of Semiconductor Thin Disk Laser

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光机电信息 2007年第12期24卷 19-25页

作者： (HE Chun-feng1, QIN Li2, LI Jun1, CHENG Li-wen1, LIANG Xue-mei1, NING Yong-qiang2, WANG Li-jun2 1. key Laboratary of Excited state Processes, Changchun Institute of Optics, Fine Mechanics and Physics, chinese {3. of {3.,Changchun 13.03., China graduate School of the chinese {3. of {3., beijing 100049, China 2. key Laboratary of Excited state Processes, Changchun Institute of Optics, Fine Mechanics and Physics, chinese {3. of {3., Changchun 13.03.,China.) key Laboratary of Excited state Processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchun 130033 China graduate School of the chinese academy of{3. Beijing 100049 China key Laboratary of Excited state Processes Changchun Institute of OpticsFine Mechanics and Physics Chinese Academy of Sciences Changchun 130033China

The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of the semiconductor disk laser, and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperatures. We can see that: with increasing pump power, the thermal effect of the gain material becomes seriously and causes the saturation of carrier lifetime, so the electron-hole pair created in the absorbtion layer has no enough time to rate to one of the wells, and the non-radiative recombination happens in the barrier. When the thermal effect becomes stronger, the chip will be not lasing. This phenomenon is from the smaller energy offset between barrier and quantum well. We optimize the original structure design and experimental technology. A non-absorbing AlGaAs layer which is transparent to the pumping and laser wavelength is added to confine the carriers in the quantum wells. At the same time a DBR with double reflecting band is induced to improve the absorbing efficiency of the pumping light. The single QW is replaced by the three narrow QWs. This three QWs structure can add the quantum state of QW, increase the recombination probability of carriers in the QWs and reduce the heat effect. The chemical etching equipment is also improved to control the surface unevenness to be within 50 nm.

关键词： thin disk laser heat effect PL spectrum, active region heat removal gain barrier spectral shift

A Novel Digital Audio Watermarking Scheme in the Wavelet Domain

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A Novel Digital Audio Watermarking Scheme in the Wavelet Dom...

The 1st chinese Conference on Trusted Computing and information security

作者： Xiang-yang, YANG Hong-ying, ZHAO Hong School of Computer and information Technique, Liaoning Normal university, Dalian 116029, Liaoning,China state {3. {3. of information security, Institute of Software of chinese academy of sciences, beijing 10003., China

＜正＞ We present a novel quantization-based digital audio watermarking scheme in wavelet domain. By quantizing a host audio’ s wavelet coefficients （Integer Lifting Wavelet Transform ） and utilizing the characteristics of human auditory system （HAS）, the gray image is embedded using our watermarking method. Experimental results show that the proposed watermarking scheme is inaudible and robust against various signal processing such as noising adding, lossy compression, low pass filtering, re-sampling, and re-quantifying.

关键词： digital audio watermarking lifting wavelet transform human auditory system chaotic sequence quantization

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多重线性密码分析的改进

通信学报 2002年第5期23卷 83-88页

作者：孙林红叶顶锋吕述望中国科学院研究生院信息安全国家重点实验室北京100039

本文介绍一种有助于对分组密码作线性密码分析并能减少有效攻击所需数据量的算法,给出了该算法成功率的计算公式,并与现有的线性密码分析方法作了比较。

关键词：多重线性密码分析分组密码线性特征

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向量递归迭代函数系统及其不变测度

系统科学与数学 2003年第2期23卷 279-288页

作者：李红达叶正麟彭国华中国科学院研究生院信息安全国家重点实验室北京100039 西北工业大学数学与信息科学系西安710072

本文阐述了RIFS和IFS之间的关系,并对定义在一组紧空间上的向量递归迭代函数系统(VRIFS),定义了Markov算子,给出Markov算子是压缩算子的条件,描述了其不动点即广义递归迭代函数系统的不变测度.文中还给出了相应的拼贴定理.

关键词：向量递归迭代函数系统不变测度 VRIFS 图像编码不动点支撑集 Markov算子图像压缩递归迭代函数系统随机过程分形