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部分Bent函数的密码学性质

通信学报 2002年第5期23卷 113-118页

作者：赵亚群冯登国李世取中国科学院研究生院信息安全国家重点实验室北京100080 郑州信息工程大学信息工程学院信息研究系河南郑州450002

本文讨论了部分Bent函数的若干密码学性质,分别给出了部分Bent函数满足平衡性、相关免疫性和扩散准则的充分必要条件,具体求出了部分Bent函数的非线性度以及部分Bent函数与仿射函数的符合率。

关键词： Bent函数密码学性质保密通信

Performance of dual-band short-or mid-wavelength infrared photodetectors based on InGaAsSb bulk materials and InAs/GaSb superlattices

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chinese Physics B 2017年第9期26卷 526-529页

作者：孙姚耀吕粤希韩玺郭春妍蒋志郝宏玥蒋洞微王国伟徐应强牛智川 state key laboratory for Supedattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Synergetic Innovation Center of Quantum information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

In this paper,we demonstrate bias-selectable dual-band short-or mid-wavelength infrared photodetectors based on In0.24Ga0.76As0.21Sb0.79 bulk materials and InAs/GaSb type-II superlattices with cutoff wavelengths of 2.2μm and 3.6μm,*** 200 K,the short-wave channel exhibits a peak quantum efficiency of 42%and a dark current density of5.93.10^-5）/cm^2at 500 mV,thereby providing a detectivity of 1.55×10^11cm·Hz^1/2/*** mid-wave channel exhibits a peak quantum efficiency of 3.%and a dark current density of 1.22×10^-3./cm^2at-3.0 mV,thereby resulting in a detectivity of 2.71×10^10cm·Hz^1/2/***,we discuss the band alignment and spectral cross-talk of the dual-band n-i-p-p-i-n structure.

关键词： short-/mid-wavelength InGaAsSb InAs/GaSb

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一个高效的门限共享验证签名方案及其应用

通信学报 2003年第5期24卷 134-139页

作者：张彰蔡勉肖国镇西安电子科技大学综合业务网国家重点实验室中科院研究生院信息安全国家重点实验室北京100039

基于离散对数问题提出一个新的门限共享验证签名方案,该方案是ElGamal签名方案和Shamir门限方案的结合。在该方案中,n个验证者中任意t个可以验证签名的有效性,而t-1个或更少的验证者不能验证签名的有效性。伪造该方案的签名等价于伪造El... 详细信息

基于离散对数问题提出一个新的门限共享验证签名方案,该方案是ElGamal签名方案和Shamir门限方案的结合。在该方案中,n个验证者中任意t个可以验证签名的有效性,而t-1个或更少的验证者不能验证签名的有效性。伪造该方案的签名等价于伪造ElGamal签名。与已有方案相比,该方案的签名效率更高。最后基于该门限共享验证签名方案提出一个新的口令共享认证方案。

关键词：门限共享验证签名口令共享认证离散对数数字签名秘密分享智能卡

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一种安全移动电子票务系统的研究

计算机工程与应用 2004年第26期40卷 184-186页

作者：邹学强冯登国中国科学院研究生院信息安全国家重点实验室北京100039

对移动电子票务系统的基本功能进行规划,提出一个基于SET协议和WAP协议的移动电子票务交易协议。在设计和分析系统的组成和结构模块后对提出系统的安全性进行讨论,最后用实例对方案的应用实施进行说明。

关键词：移动电子票务网络安全

Construction of Convolutional Network Coding for Cyclic Multicast Networks

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Construction of Convolutional Network Coding for Cyclic Mult...

2010 IEEE 2nd Symposium on Web Society

作者： Qin Guo~(1,2,3.,Mingxing Luo~(1,2,3.,Lixiang Li~(1,2,3.,Licheng Wang~(1,2,3.,Yixian Yang~(1,2,3. 1 information security Center,state {3. {3. of Networking and Switching Technology, beijing university of Posts and Telecommunications,beijing 100876,China 2 {3. {3. of Network and information Attack and Defence Technology of MOE, beijing university of Posts and Telecommunications,beijing 100876,China 3.National Engineering {3. for Disaster Backup and Recovery, beijing university of Posts and Telecommunications,beijing 100876,China.

＜正＞In this paper,we present a practical algorithm to construct the convolutional multicast network coding over any finite directed cyclic *** dual line graph of a directed cyclic graph is considered as a *** regarding the global encoding kernels in the original graph as the corresponding inputs or outputs of some subsystem and the local encoding kernels in original graph as gains of channels,we can construct the convolutional network code through randomly choosing the local encoding kernels of the directed cycles in *** using Mason formula,the construction becomes very efficient.

关键词： Convolutional network code convolutional multicast dual line graph Mason formula

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存在特权集的代理门限群签名方案

计算机工程与应用 2004年第25期40卷 31-34页

作者：谭作文刘卓军陈伟东中国科学院数学与系统科学研究院系统科学研究所中国科学院研究生院信息安全国家重点实验室北京100039 中国科学院研究生院信息安全国家重点实验室中国科学院电子所北京100080

在Schnorr代理签名的基础上,结合存在特权集的门限群签名,提出了两个存在特权集的代理群签名方案。它们具有门限群签名的特点,同时实现了不同代理人的不等代理权限功能。基于离散对数假设,对这两个代理门限群签名方案进行了安全分析。

关键词：代理签名 Schnorr签名门限群签名离散对数假设

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算术级数中的奇数Goldbach问题

数学学报（中文版） 2003年第5期46卷 965-980页

作者：张振峰王天泽中国科学院研究生院信息安全国家重点实验室北京100039 河南大学数学与信息科学学院开封475001

本文给出了算术级数的模的精确数值上界,在该算术级数中奇数Goldbach问题可解。我们的结果蕴含了Linnik常数的一个数值上界。

关键词：奇数Goldbach问题素数算术级数

Modulation of theta and gamma oscillations in central olfactory pathway by behavioral state

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Modulation of theta and gamma oscillations in central olfact...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Qing LIU~(1,3.,Rui-Qi WU~(1,3.,An-An LI~1,Fu-Qiang XU~(1,2,*) 1 Wuhan MRC,state key laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,the {3. {3. of Science,Wuhan 43.071,China 2 Wuhan National laboratory for Optoelectronics,Wuhan 43.074,China 3.graduate university of {3. {3. of Science,beijing 100049,China

＜正＞Objective In mammalian olfactory pathway,the oscillatory activities of the olfactory bulb（OB）,piriform cortex（PCX）and hippocampus（HPC）have been extensively studied to elucidate odor information processing. However,less is known about the oscillations of spontaneous activity and the modulation by behavioral state, especially for the theta（4-12 Hz）and gamma（3.-100 Hz）*** In the present study,local field potentials （LFP）of spontaneous activity were recorded from the OB,PCX and HPC simultaneously in awake and anesthetized *** Compared with the anesthetized state,awake mice showed increased theta and gamma oscillations in all the three regions,but decreased coherences among ***,the spontaneous activities in exploratory walking and motionless mice were *** exploratory state,the power of theta oscillations in the PCX and HPC was decreased,whereas the power of theta in the OB and gamma in all regions were increased significantly. However,the coherences among the three brain regions for both theta and gamma oscillations were significantly *** was also found that the coherence between the PCX and the HPC was always the highest regardless of brain *** These results suggest that the theta and gamma oscillations in central olfactory pathway could be modulated by behavioral state,and that the higher coherences of both theta and gamma oscillations between PCX and HPC indicate tighter functional coupling between them.

关键词： oscillation olfactory bulb piriform cortex hippocampus functional coupling

Statistical characteristics of gravity wave activities observed by an OH airglow imager at Xinglong, in northern China

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Statistical characteristics of gravity wave activities obser...

第十四届全国日地空间物理学术研讨会

作者： Q. Li1,2 J. Xu1 J. Yue3.W. Yuan1 and X. Liu1,4 (1 state key laboratory of Space Weather, Center for Space Science and Applied Research, {3. {3. of sciences, beijing 100190, China ) (2 graduate university of the {3. {3. of sciences, beijing 100049, China ) (3.High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO 803.7, USA ) (4 College of Mathematics and {13. Science, Henan Normal university, Xinxiang, China )

An all-sky airglow imager （ASAI） was installed at Xinglong, in northern China （40.2oN, 117.4oE） in November 2009 to study the morphology of atmospheric gravity waves （AGWs） in the mesosphere and lower thermosphere （MLT） region. Using one year of OH airglow imager data from December 2009 to November 2010, the characteristics of short-period AGWs are investigated and a yearlong AGW climatology in northern China is first ever reported. AGW occurrence frequency in summer and winter is higher than that in equinoctial months. Observed bands mainly have horizontal wavelengths from 10 to 3. km, observed periods from 4 to 14 min and observed horizontal phase speeds in the range of 3. to 60 m/s. Most of the bands propagate in the meridional direction. The propagation directions of the bands show a strong southwestward preference in winter, while almost all bands propagate northeastward in summer. Although the wind filtering in the middle atmosphere may control AGW propagations in the zonal direction, the non-uniform distribution of wave sources in the lower atmosphere may contribute to the anisotropy in the meridional direction in different seasons. Additionally, as an indication of local instability, the characteristics of ripples are also analyzed. It also shows seasonal variations, occurring more often in summer and winter and mainly moving westward in summer and eastward in winter.

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