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Calibration based universal JPEG steganalysis

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science in{1.(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 {1. science and technology Sun Yat-Sen University Guangzhou China Guangdong Key Lab. of information Security {1. 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

Twisted Ate pairing on hyperelliptic curves and applications

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science{1.(information sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1.2 1.school of {1. science and technology, sun yat-sen university, guangzhou 510275, china 2 Guangdong Key Laboratory of {1. Security technology, guangzhou 510275, china school of {1. science and technology Sun Yat-Sen University Guangzhou China Guangdong Key Laboratory of information Security {1. 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

A provable secure fuzzy identity based signature scheme

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science{1.(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 {1. 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

A Deniable Authenticated Key Agreement Protocol

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Wuhan university Journal of Natural {1.s 2008年第6期13卷 645-650页

作者： TIAN Haibo1.2, CheN Xiaofeng1.2, ZHANG Fangguo1.2, WEI Baodian1.{1., sun yat-sen university, guangzhou 51.006, Guangdong, china 2. Guangdong Key Laboratory of information Security technology, sun yat-sen university, guangzhou 510275, Guangdong, china school of {1. science and technology Sun Yat-Sen University Guangzhou China Guangdong Key Laboratory of information Security {1. Sun Yat-Sen University Guangzhou China

This paper presents a deniable aut{1.nticated key agreement protocol. This protocol can provide an aut{1.nticated session key while t{1. sender and t{1. receiver can deny t{1.ir involvement in such a protocol if t{1. protocol is executed successfully. T{1.n both can deny t{1.ir transmitted messages protected by t{1. aut{1.nticated session key. If this protocol fails, no aut{1.nticated session key can be establis{1.d and no protected messages can be transmitted. T{1. protocol can be proved secure against key compromise impersonation attack. T{1. protocol employs a new method to isolate a session key from confirmation keys.

关键词： deniable authentication key agreement key compromise impersonation

Secure multi-party computation protocol for sequencing problem

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science{1.(information sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1,2,SHI GuiHua 1 & YAO ZhengAn 3 1 school of Mathematics and information science,guangzhou university,guangzhou 510006, china 2State Key Laboratory of information Security, Institute of Software science,Chinese Academy of sciences,Beijing 100080,china 3 school of Mathematics and Computational science,sun yat-sen university,guangzhou 510275,china school of Mat{1.matics and information science Guangzhou University Guangzhou China State Key Laboratory of information Security Institute of Software Science Chinese Academy of Sciences Beijing China school of Mat{1.matics and Computational science Sun Yat-Sen University Guangzhou China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1./2 participants, and an active adversary that can corrupt at most t he Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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science{1.(information sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1,DAI XianHua 2 & Pan DaRu 1 1 school of Physics and Telecommunication Engineering,South china Normal university,guangzhou 510006,china 2 Department of information science and technology,sun yat-sen university,guangzhou 510026,china school of Physics and Telecommunication Engineering South China Normal University Guangzhou China Department of information {1. and technology SUN Yat-sen University Guangzhou China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

Perceptual video hashing robust against geometric distortions

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science{1.(information sciences) 2012年第7期55卷 1520-1527页

作者： XIANG ShiJun 1.4 ,YANG JianQuan 2 & huang {1. 3 1.school of information science and technology,Jinan university,guangzhou 51.632,china 2 Shenzhen Institutes of Advanced technology,Chinese Academy of sciences,Shenzhen 51.055,china 3 school of information science and technology,sun {21.-sen university,guangzhou 510275,china 4 State Key Laboratory of information Security,Institute of Software,Chinese Academy of sciences,Beijing 1.0049,china school of {1. science and technology Jinan University Guangzhou China State Key Laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China Shenzhen Institutes of Advanced technology Chinese Academy of Sciences Shenzhen China school of {1. science and technology Sun Yat-sen University Guangzhou China

In this paper,we propose a robust perceptual hashing algorithm by using video luminance histogram in *** underlying robustness principles are based on three main aspects:1. Since the histogram is independent of position of a pixel,the algorithm is resistant to geometric deformations; 2) the hash is extracted from the spatial Gaussian-filtering low-frequency component for those common video processing operations such as noise corruption,low-pass filtering,lossy compression,etc.; 3) a temporal Gaussian-filtering operation is designed so that the hash is resistant to temporal desynchronization operations,such as frame rate change and *** a result,the hash function is robust to common geometric distortions and video processing *** results show that the proposed hashing strategy can provide satisfactory robustness and uniqueness.

关键词： video hashing geometric distortion histogram Gaussian filtering

An Aggregation Composition Compensation Method Based on Paired Net

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International Journal of Automation and computing 2012年第5期9卷 530-538页

作者： Xiao-Yong Mei 1,2 Yi-Yan Fan 2 Chang-Qin huang 3 Ai-Jun Jiang 1 Shi-Xian Li 1 1 school of information science and technology,sun yat-sen university,guangzhou 510006,china 2 school of Computer science and technology,Hunan university of Arts and science,Changde 415000,china 3 Department of Electrical Engineering and Computer science,university of California,Irvine,CA,92697,USA school of {1. science and technology Sun Yat-sen University Guangzhou China school of Computer {1. and technology Hunan University of Arts and Science Changde China Department of Electrical Engineering and Computer science University of California Irvine USA

With regard to the failure and cancellation of business logic of web services composition(WSC),this paper propose a novel web services transaction compensation mechanism based on paired net which can dynamically establish agile compensation-triggered process(CSCP-Nets),and satisfy prospective compensation *** related execution semantics of five usual composition compensation patterns based on paired net are analyzed in the situations of successful execution,failure compensation and failure *** net based application of trip reservation process(TRP) shows that it is feasible.

关键词： Web services composition failure handling composition compensation execution semantic analysis paired net

Non-invasive in Situ Simultaneous Measurement of Multi-parameter Mechanical Properties of Red Blood Cell Membrane

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Acta Biochimica et Biophysica Sinica 2005年第6期37卷 391-395页

作者： Jing LI~(1.2) Yao-Xiong huang~1.Tao JI~1.Mei TU~1.Xuan MAO~1.Wen-Xin C{1.N~1.Guang-Wei C{1.N 1.Institute of Biomedical Engineering, Jinan university, guangzhou 51.632, china 2 State Key Laboratory for Biocontrol, school of Life science, sun yat-sen university, guangzhou 510275, china Institute of Biomedical Engineering Jinan University Guangzhou 510632 China State Key Laboratory for Biocontrol School of Life Science Sun Yat-Sen University Guangzhou 510275 China

The purpose of this study was to develop a new dynamic image analyzing technique that willgive us the ability to measure the viscoelastic parameters of individual living red blood cells non-invasively,insitu and in real *** this technique,the bending modulus Kc,the shear elasticity μ and their ratio ε weremeasured under different temperatures,oxygen partial pressures and osmotic *** results not onlyshow the effects of external conditions on mechanical properties of cell membranes including deformability,flexibility,adhesive ability and plasticity,but also demonstrate that the technique can be used to measure cellmembrane parameters continuously under several physiological and pathological conditions.

关键词： fast image analyzing red blood cell(RBC) cell membrane elastic property