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Practical security against linear cryptanalysis for SMS4-like ciphers with SP round function

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Science china(information Sciences) 2012年第9期55卷 2161-2170页

作者： ZHANG Bin 1,2 & JIN ChenHui 2 1 P.O.Box 1936,Beijing 100193,china 2 electronic technology Institute,information engineering university,zhengzhou 450004,china 1. P.O.Box 1936 Beijing 100193 China2. Electronic Technology Institute Information Engineering University Zhengzhou 450004 China

SMS4,a block cipher whose global structure adopts a special unbalanced Feistel scheme with SP round function,is accepted as the Chinese National Standard for securing Wireless *** this paper,in order to evaluate the security against linear cryptanalysis,we examine the upper bound of the maximum linear characteristic probability of SMS4-like ciphers with SP round *** the same way as for SPN ciphers,it is sufficient to consider the lower bound of the number of linear active *** propose a formula to compute the lower bound of the number of linear active s-boxes with regard to the number of *** security threshold of SMS4-like ciphers can be estimated easily with our ***,if the number of input words in each round of SMS4-like cipher is m,we find that it is unnecessary for designers to make the linear branch number of P greater than 2 m with respect to linear cryptanalysis.

关键词： block cipher SMS4-like cipher practical security linear cryptanalysis

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5 1 College of Computer Science and technology,Beijing university of technology,Beijing 100022,china 2 State Key Laboratory of information Security (Graduate university of the Chinese Academy of Sciences),Beijing 100049,china 3 School of Science,Beijing university of Posts and Telecommunications,Beijing 100876,china 4 Institute of electronic technology,information engineering university,zhengzhou 450004,china 5 Trusted Computing Laboratory,Beijing university of technology,Beijing 100022,china College of Computer Science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of information Security [Graduate university of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of electronic technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

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Relation of chaos activity characteristics of the cardiac system with the evolution of species

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Chinese Science Bulletin 2002年第24期47卷 2042-2048页

作者： WANG XingyuanSchool of electronic and information engineering, Dalian university of technology, Dalian 116024, china Dalian university of technology School of Electronic and Information Engineering Dalian China

According to the nonlinear theory, the experiments have been conducted on sample ECG (electrocardiogram) signals of healthy human beings, coronary heart disease patients and adult canines. On the basis of the analyses of the power spectra, the computation of the correlation dimension and the Lyapunov exponent to a large number of ECG signals, the following conclusions are shown: through the comparative research, (1) the analyses of the power spectra, the computation of the correlation dimension and the Lyapunov exponent to the ECG signals reflect the whole dynamic characteristics of the hearts, and they may become a new method of researching ECG quantitatively to an early diagnose of heart disease. (2) Under normal physiological conditions the cardiac activities are chaotic, while under pathologic conditions the cardiac activities approach regularity. (3) On the basis of the comparative research of human beings and canines, it is revealed that chaos may be a quantitative index to measure the evolution

关键词： chaos evolution of species ECG signals power spectra correlation dimension Lyapunov exponent.

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An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

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Progress in Natural Science:Materials International 2007年第10期17卷 1235-1240页

作者： Fan Hongjuan1, Feng Jiuchao1,2, Xie Shengli2 and Wang Shiyuan1(1. Faculty of electronic and information engineering ,Southwest university, Chongqing 400715, china 2. School of electronic and information engineering, South china university of technology, Guangzhou 510641, china) Faculty of electronic and information engineering Southwest University Chongqing 400715 China School of electronic and information engineering South China University of Technology Guangzhou 510641 China

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

关键词： chaos unscented Kalman filter Lyapunov exponents aperiodicity.

Efficient CRT-based residue-to-binary converter for the arbitrary moduli set

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Science china(information Sciences) 2011年第1期54卷 70-78页

作者： CHEN JianWen & YAO RuoHe School of electronic and information engineering,South china university of technology, Guangzhou 510640,china 1. School of electronic and information engineering South China University of Technology Guangzhou 510640 China

The conversion from residue to weighted binary representation plays an important role in the residue number *** on Chinese Remainder Theorem,a new residue-to-binary converter using arbitrary moduli set is *** new converter uses the difference-correction algorithm for the conversion output and eliminates the modulo M operation,where M is the dynamic range of the residue number *** sizes of the multipliers and modular multipliers in the new converter are small,thereby reducing the area and delay of the proposed *** and synthesis results indicate that the new converter is more area-time effcient than the published converters based on Chinese Remainder Theorem.

关键词： RNS Chinese Remainder Theorem difference correction modular arithmetic residue-to-binary arbitrary moduli set

Dynamics of the generalized 3x + 1 function determined by its fractal images

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Progress in Natural Science:Materials International 2008年第2期18卷 217-223页

作者： Xingyuan Wang ,Xuejing Yu School of electronic & information engineering,Dalian university of technology,Dalian 116024,china School of electronic & information engineering Dalian University of Technology Dalian 116024 China

Two different complex maps were obtained by generalizing 3x + 1 function to the complex plane,and fractal images for these two complex maps were constructed by using escape time,stopping time and total stopping time arithmetic. The dynamics of the generalized 3x + 1 function based on the structural characteristics of the fractal images was studied. We found that: (1) the size and structure of the stable regions,stopping regions,total stopping regions,and divergent regions for the three types of fractal images depend on convergence rate of the map on the x and y axes. (2) The black stable regions constructed,respectively,by escape time and total stopping time are almost overlapped,demonstrating that 3x + 1 function converged steadily. (3) All of the three fractal images are symmetric to the real axis. The structures on the neighborhood of positive integer number are symmetric to a perpendicular line,which is corresponding to the point or its nearby points on the x axis. And the structures have complicated fractal structure characteristics. These findings indicate that the generalized 3x + 1 function on integer number and its neighborhood contains plentiful information in the complex plane.

关键词： Generalized 3x + 1 function Fractal images Dynamics

RBF neural network and active circles based algorithm for contours extraction

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Progress in Natural Science:Materials International 2007年第6期17卷 681-686页

作者： Zhou Zhiheng, Zeng Delu and Xie Shengli(College of electronic & information engineering, South china university of technology, Guangzhou 510640, china) College of electronic and information engineering South China University of Technology Guangzhou 510640 China

For the contours extraction from the images, active contour model and self-organizing map based approach are popular nowadays. But they are still confronted with the problems that the optimization of energy function will trap in local minimums and the contour evolutions greatly depend on the initial contour selection. Addressing to these problems, a contours extraction algorithm based on RBF neural network is proposed here. A series of circles with adaptive radius and center is firstly used to search image feature points that are scattered enough. After the feature points are clustered, a group of radial basis functions are constructed. Using the pixels’ intensities and gradients as the input vector, the final object contour can be obtained by the predicting ability of the neural network. The RBF neural network based algorithm is tested on three kinds of images, such as changing topology, complicated background, and blurring or noisy boundary. Simulation results show that the proposed algorithm performs contours extraction greatly.

关键词： contours extraction RBF neural network dynamic clustering.

Vector bundle constraint for particle swarm optimization and its application to active contour modeling

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Progress in Natural Science:Materials International 2007年第10期17卷 1220-1225页

作者： Zeng Delu, Zhou Zhiheng and Xie Shengli(College of electronic and information engineering, South china university of technology, Guangzhou 510641, china) College of electronic and information engineering South China University of Technology Guangzhou 510641 China

Active contour modeling (ACM) has been shown to be a powerful method in object boundary extraction. In this paper, a new ACM based on vector bundle constraint for particle swarm optimization (VBCPSO-ACM) is proposed. Different from the traditional particle swarm optimization (PSO), in the process of velocity update, a vector bundle is predefined for each particle and velocity update of the particle is restricted to its bundle. Applying this idea to ACM, control points on the contour are treated as particles in PSO and the evolution of the contour is driven by the particles. Meanwhile, global searching is shifted to local searching in ACM by decreasing the number of neighbors and inertia. In addition, the addition and deletion of particles on the active contour make this new model possible for representing the real boundaries more precisely. The proposed VBCPSO-ACM can avoid self-intersection during contour evolving and also extract inhomogeneous boundaries. The simulation results proved its great performance in performing contour extraction.

关键词： boundary extraction active contour modeling particle swarm optimization velocity update vector bundle.

A fast stereoscopic video coding algorithm based on JMVM

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Science china(information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2 , JIA KeBin 1 , CHAN YuiLam 2 , FU ChangHong 2 & SIU WanChi 2 1 Department of electronic information & Control engineering, Beijing university of technology, Beijing 100124, china 2 Department of electronic information engineering, Hong Kong Polytechnic university, Hong Kong, china 1. Department of electronic information & Control engineering Beijing University of Technology Beijing 100124 China2. Department of Electronic Information Engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.264 stereoscopic video coding disparity estimation motion estimation