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MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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Science China(information Sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2 & YANG LuXi 2 1 College of Communication and information Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China 2 school of information Science and Engineering,Southeast University,Nanjing 210096,China College of Communication and information Engineering Nanjing University of Posts and Telecommunications Nanjing China school of information Science and Engineering Southeast University Nanjing China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Twisted Ate pairing on hyperelliptic curves and applications

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Science China(information Sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1,2 1 school of information Science and Technology, Sun Yat-Sen University, Guangzhou 510275, China 2 Guangdong Key Laboratory of information Security Technology, Guangzhou 510275, China school of information Science and Technology Sun Yat-Sen University Guangzhou China Guangdong Key Laboratory of information Security Technology Guangzhou China

In this paper we show that the twisted Ate pairing on elliptic curves can be generalized to hyperelliptic curves, and give a series of variations of the hyperelliptic Ate and twisted Ate pairings. Using the hyperelliptic Ate pairing and twisted Ate pairing, we propose a new approach to speeding up the Weil pairing computation. For some hyperelliptic curves with high degree twist, computing Weil pairing by our approach may be faster than Tate pairing, Ate pairing, and all other known pairings.

关键词： Ate pairing Weil pairing hyperelliptic curves pairing-based cryptosystems twisted curves

Adaptive synchronization of neural networks with different attractors

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Progress in Natural Science:Materials International 2007年第6期17卷 687-695页

作者： Zhang Huaguang1, Guan Huanxin1 and Wang Zhanshan1,2(1. school of information Science and Engineering, Northeastern University, Shenyang 110004, China 2. school of information Science and Engineering, Shenyang Ligong University, Shenyang 110168, China) school of information Science and Engineering Northeastern University Shenyang 110004 China school of information Science and Engineering Shenyang Ligong University Shenyang 110168 China

This paper aims to present an adaptive control scheme for the synchronization of two classes of uncertain neural networks with different attractors. A new sufficient condition for the global synchronization of two kinds of neural networks with different attractors is derived. The proposed control method is efficient and easy to be implemented. Numerical simulation is used to show the effectiveness of the obtained result.

关键词： neural networks attractor adaptive synchronization linear matrix inequality.

Fuzzy H∞ Filter Design for a Class of Nonlinear Systems with Time Delays via LMI

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自动化学报 2005年第3期 64-71页

作者： LUN Shu-Xian~(1’2) ZHANG Hua-Guang~1 ~1(school of information Science and Engineering,Northeastern University,Shenyang 110004)~2(school of information Science and Engineering,Bohai University,Jinzhou 110004)

This paper develops fuzzy Hfilter for state estimation approach for nonlinear discrete- time systems with multiple time delays and unknown bounded *** design a stable fuzzy Hfilter based on the Takagi-Sugeno (T-S) fuzzy model,which assures asymptotic stability and a prescribed Hindex for the filtering error *** condition for the existence of such a filter is established by solving the linear matrix inequality (LMI) *** LMI problem can be efficiently solved with global convergence using the interior point *** examples are provided to illustrate the design procedure of the proposed method.

关键词： Nonlinear systems H_∞ filter state estimation Takagi-Sugeno fuzzy model time delays linear matrix inequality(LMI)

A provable secure fuzzy identity based signature scheme

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Science China(information Sciences) 2012年第9期55卷 2139-2148页

作者： WANG ChangJi 1,2 1 school of information Science and Technology,Sun Yat-sen University,Guangzhou 510275,China 2 Guangdong Province information Security Key Laboratory,Sun Yat-sen University,Guangzhou 510275,China school of information Science and Technology Sun Yat-sen University Guangzhou China Guangdong Province information Security Key Laboratory Sun Yat-sen University Guangzhou China

To use biometrics identities in an identity based encryption system,Sahai and Waters first introduced the notion of fuzzy identity based encryption(FIBE) in *** et *** it to digital signature and introduced the concept of fuzzy identity based signature(FIBS) in 2008,and constructed an FIBS scheme based on Sahai and Waters's FIBE *** this paper,we further formalize the notion and security model of FIBS scheme and propose a new construction of FIBS scheme based on bilinear *** proposed scheme not only provides shorter public parameters,private key and signature,but also have useful structures which result in more efficient verification than that of Yang et al.'s FIBS *** proposed FIBS scheme is proved to be existentially unforgeable under a chosen message attack and selective fuzzy identity attack in the random oracle model under the discrete logarithm assumption.

关键词： identity based cryptosystem fuzzy identity based encryption fuzzy identity based signature

Predictive control and scheduling codesign in network control systems

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控制理论与应用（英文版） 2010年第2期8卷 239-244页

作者： Qing SHEN 1 , 2 , Weihua GUI 2 , Ying XIONG 2 , Chunhua YANG 2 (1.school of Basic Education for Officers, National University of Defense Technology, Changsha Hunan 410003, China 2.school of information Science and Engineering, Central South University, Changsha Hunan 410083, China) school of Basic Education for Officers National University of Defense Technology Changsha Hunan China school of information Science and Engineering Central South University Changsha Hunan China

A codesign approach combining predictive control compensation and network scheduling is presented in this paper to overcome the adverse influences of stochastic time delays and packet losses encountered in network-based real-time control systems. The state estimation and control prediction compensation algorithms are used for the random network delays in the feedback and forward channels, and the stability criteria are analyzed. The proper sampling rate is given with network scheduling to meet the desired system performance, while the network-induced delay is tolerated. Simulations show that the codesign approach works well with the bounded network delay.

关键词： Network control system Prediction Scheduling Stability

维普期刊数据库

Calibration based universal JPEG steganalysis

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Science in China(Series F) 2009年第2期52卷 260-268页

作者： HUANG FangJun1,2 & HUANG JiWu1,2 1 school of information Science and Technology,Sun Yat-Sen University,Guangzhou 510275,China 2 Guangdong Key Lab. of information Security Technology,Sun Yat-Sen University,Guangzhou 510275,China school of information Science and Technology Sun Yat-Sen University Guangzhou China Guangdong Key Lab. of information Security Technology Sun Yat-Sen University Guangzhou China

For steganalysis of JPEG images, features derived in the embedding domain appear to achieve a preferable performance. However, with the existing JPEG steganography, the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT （BDCT） coefficients in that the energy of the carrier image is much larger than that of the hidden signal. In this paper, we present an improved calibration-based universal JPEG steganalysis, where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image. All features in our method are generated from the difference signal be- tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image, or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image. The extracted features will be more effective for our classification. Moreover, through using the Markov empirical transition matrices, both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.

关键词： JPEG steganography steganalysis microscopic calibration macroscopic calibration

维普期刊数据库

Group sparse representation for image categorization and semantic video retrieval

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Science China(information Sciences) 2011年第10期54卷 2051-2063页

作者： LIU YaNan 1,2 ,WU Fei 2 & ZHUANG YueTing 2 1 school of information,Zhejiang University of Finance & Economics,Hangzhou,310018,China 2 College of Computer Science and Technology,Zhejiang University,Hangzhou,310012,China school of information Zhejiang University of Finance & Economics Hangzhou China College of Computer Science and Technology Zhejiang University Hangzhou China

Multimedia content analysis and management are a promising and challenging *** this paper we develop a novel approach to image representation,which we call group sparse representation (GSR),for image classification and video *** basic idea is to represent a test image as a weighted combination of all the training *** particular,we introduce two sets of weight coefficients,one for each training image and the other for each ***,we formulate our concern as a group nonnegative garrote *** resulting representations are sparse,and they are appropriate for discriminant *** on Caltech101 and PASCAL VOC2008 image dataset and TRECVID2005 video corpus testify that our proposed approach is efficient and effective.

关键词： compressive sensing group sparse representation bag-of-SIFT-words nonnegative garrote l1-minimization apcluster

Balanced multiple description subband coding based on multifilter banks

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Science China(information Sciences) 2011年第11期54卷 2359-2372页

作者： WANG Ning 1,LI BaoBin 2 & PENG LiZhong 1 1 LMAM,school of Mathematical Sciences,Peking University,Beijing 100871,China 2 school of information Science and Engineering,Graduate University of Chinese Academy of Sciences,Beijing 100190,China LMAM School of Mathematical Sciences Peking University Beijing China school of information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing China

Multiple description coding is one of the source coding techniques to alleviate the problems of packet loss in *** encoder generates several different descriptions of the source and the decoder can produce a useful reconstruction with any received subset of these *** of the earlier works concentrated on redundancy and the average distortion of the single-description reconstructions,which is insufficient to describe the *** this paper,a metric of the coding system,balance eccentric modulus,is defined to evaluate the difference in quality between the individual *** the discrete wavelet transform becomes trivial polyphase transform when setting the balance eccentric modulus at zero,we introduce a multiwavelet based scheme ***,a sufficient condition for balanced multiwavelet based multiple description coding is presented.

关键词： multiple description coding rate-distortion theory balance eccentric modulus balanced multiwavelet multifilter bank