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A novel color image encryption algorithm based on genetic recombination and the four-dimensional memristive hyperchaotic system

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Chinese Physics B 2016年第10期25卷 76-88页

作者：柴秀丽甘志华路杨张苗辉陈怡然 school of Computer and information engineering Institute of Image Processing and Pattern Recognition Henan University Department of Electrical and Computer engineering University of Pittsburgh school of Software Henan University Research Department Henan University

Recently, many image encryption algorithms based on chaos have been proposed. Most of the previous algorithms encrypt components R, G, and B of color images independently and neglect the high correlation between them. In the paper, a novel color image encryption algorithm is introduced. The 24 bit planes of components R, G, and B of the color plain image are obtained and recombined into 4 compound bit planes, and this can make the three components affect each other. A four-dimensional(4D) memristive hyperchaotic system generates the pseudorandom key streams and its initial values come from the SHA 256 hash value of the color plain image. The compound bit planes and key streams are confused according to the principles of genetic recombination, then confusion and diffusion as a union are applied to the bit planes,and the color cipher image is obtained. Experimental results and security analyses demonstrate that the proposed algorithm is secure and effective so that it may be adopted for secure communication.

关键词： genetic recombination memristive hyperchaotic system color image encryption confusion diffusion

First-principles calculations and experimental studies of Sn-Zn alloys as negative electrode materials for lithium-ion batteries

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Rare Metals 2011年第2期30卷 160-165页

作者： RU Qiang PENG Wei ZHANG Zhiwen HU Shejun LI Yanling Laboratory of Quantum information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

The physical characters and electrochemical properties of various phases in a Sn-Zn electrode, such as formation energy, plateau potential, specific capacity, as well as volume expansion, were calculated by the first-principles plane-wave pseudo-potential method based on the den- sity functional theory. Sn-Zn films were also deposited on copper foils by an electroless plating technique. The actual composition and chemical characters were explored by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, plasma atomic emission spectrometry （ICP）, and constant current charge/discharge measurements （CC）. The results show that separation phases with tin and zinc including a small quantity of Cu6Sn5 phase were obtained, the initial lithium insertion capacity of the Sn-Zn film was 661 mAh/g, and obvious potential pla- teaus of about 0.4 V and 0.7 V were displayed, which is in accordance with the results of theoretical calculations. The capacity of the Sn-Zn film decreased seriously with the increase of cycle number.

关键词： lithium batteries electrochemical electrodes tin alloys first-principles calculations

On the Effects of Exploring Historical Commit Messages for Developer Recommendation

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Chinese Journal of Electronics 2016年第4期25卷 658-664页

作者： YANG Hui SUN Xiaobing DUAN Yucong LI Bin school of information engineering Yangzhou University State Key Laboratory for Novel Software Technology Nanjing University Hainan University

Many developer recommendation techniques have been developed in the *** existing studies,most of them are performed based on exploring the historical commit *** thought behind them is that developers who submit similar historical commits relevant to the incoming issue are more probably to be the candidates for the current issue *** whether such a thought is always useful for developer recommendation? This paper aims at this problem by conducting a set of empirical studies on four real open-source pro *** results show that,1) historical commit messages do well reflect the historical experience of the maintenance task of developers and can be used for developer recommendation in most of the time;2) the number of historical commits submitted by the recommended developer(s) and the similarity value used to select the relevant historical commits should be carefully considered to recommend developers for issue resolution;3) The efficiency of issue resolution process can be improved if some associated source code files relevant to this issue can be also recommended;and 4) developer recommendation techniques that rank the recommended developers based on the times of co-changed source code files cannot always produce correct recommendation results.

关键词： Developers recommendation Historical commit messages Empirical study

Phase retrieval algorithm for optical information security

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Chinese Physics B 2019年第8期28卷 132-147页

作者： Shi-Qing Wang Xiang-Feng Meng Yu-Rong Wang Yong-Kai Yin Xiu-Lun Yang Department of Optics School of Information Science and Engineering and Shandong Provincial Key Laboratory of Laser Technology and ApplicationShandong University

As a typical technology for optical encryption,phase retrieval algorithms have been widely used in optical information encryption and authentication *** paper presents three applications of two-dimensional(2D)phase retrieval for optical encryption and authentication:first,a hierarchical image encryption system,by which multiple images can be hidden into cascaded multiple phase masks;second,a multilevel image authentication system,which combines(t,n)threshold secret sharing(both t and n are positive integers,and t≤n)and phase retrieval,and provides both high-level and low-level authentication;and finally,a hierarchical multilevel authentication system that combines the secret sharing scheme based on basic vector operations and the phase retrieval,by which more certification images can be encoded into multiple cascaded phase masks of different hierarchical *** three phase retrieval algorithms can effectively illustrate phase-retrievalbased optical information *** principles and features of each phase-retrieval-based optical security method are analyzed and *** is hoped that this review will illustrate the current development of phase retrieval algorithms for optical information security and will also shed light on the future development of phase retrieval algorithms for optical information security.

关键词： phase retrieval algorithm authentication system image encryption

SIGNAL CONSTELLATIONS DESIGN FOR DIFFERENTIAL UNITARY SPACE-TIME IN MIMO-OFDM SYSTEM OVER FREQUENCY-SELECTIVE FADING CHANNELS

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Journal of Electronics(China) 2008年第3期25卷 300-304页

作者： Chen Jing Zhu Qi College of communication ＆ information engineering Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

In this paper, the design of signal constellations parameters is studied for Differential Unitary Space-Time Modulation (DUSTM) based on the design criterion of maximizing the diversity product. Further, noninteger searching method for the signal constellation parameters design is proposed in order to get better codes. Experimental results show that under the different Doppler spread and data transmission rate, the proposed design performs better than the previous design using integer parameters in Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system over frequency-selective fading channels.

关键词： Differential Unitary Space-Time Modulation (DUSTM) Diversity product Signal constellations Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Mutiplexing (OFDM)

Identity-based proxy multi-signature applicable to secure E-transaction delegations

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High Technology Letters 2016年第2期22卷 199-206页

作者：刘建华 Wu Qianhong Liu Jianwei Shang Tao Aviation engineering Institute Civil Aviation Flight University of China school of Electronics and information engineering Beihang University

To enhance the robustness of a proxy multi-signature scheme and improve its efficiency, a novel proxy signature paradigm is proposed referred to as In this paradigm, multiple proxy signer candidates identity-based proxy multi-signature （IBPMS）. are employed to play a role of the single proxy signer in the existing model. A provably secure IBPMS scheme is presented which requires only one round broadcast operation. Performance analysis demonstrates that the new scheme outperforms the existing multi-signature schemes in robustness and communication. These properties are rendered to our IBPMS scheme as a more practical solution to secure e-transaction delegation applications of proxy signatures.

关键词： multi-signature E-transaction delegation provable security information security

Efficient Quantum Secure Direct communication with Authentication

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Chinese Physics Letters 2008年第7期25卷 2354-2357页

作者：刘文杰陈汉武李志强刘志昊 school of Computer Science and engineering Southeast University Nanjing 210096 school of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044

Two protocols of quantum direct communication with authentication [Phys. Rev. A 73 （2006） 042305] were recently indicated to be insecure against the authenticator Trent attacks [Phys. Rev. A 75 （2007） 026301]. We present two efficient protocols by using four Panli operations, which are secure against inner Trent attacks as well as outer Eve attacks. Finally, we generalize them to multiparty quantum direction communication.

关键词： KEY DISTRIBUTION ENTANGLEMENT PHOTONS STATES

Hybrid Model of Molten Steel Temperature Prediction Based on Ladle Heat Status and Artificial Neural Network

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Journal of Iron and Steel Research International 2014年第2期21卷 181-190页

作者： Fei HE Dong-feng HE An-jun XU Hong-bing WANG Nai-yuan TIAN school of Metallurgical and Ecological engineering University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing school of Computer and communication engineering University of Science and Technology Beijing

Aiming at the characteristics of the practical steelmaking process, a hybrid model based on ladle heat sta- tus and artificial neural network has been proposed to predict molten steel temperature. The hybrid model could over- come the difficulty of accurate prediction using a single mathematical model, and solve the problem of lacking the consideration of the influence of ladle heat status on the steel temperature in an intelligent model. By using the hybrid model method, forward and backward prediction models for molten steel temperature in steelmaking process are es- tablished and are used in a steelmaking plant. The forward model, starting from the end-point of BOF, predicts the temperature in argon-blowing station, starting temperature in LF, end temperature in LF and tundish temperature forwards, with the production process evolving. The backward model, starting from the required tundish tempera- ture, calculates target end temperature in LF, target starting temperature in LF, target temperature in argon-blo- wiag station and target BOF end-point temperature backwards. Actual application results show that the models have better prediction accuracy and are satisfying for the process of practical production.

关键词： steelmaking process hybrid model ladle heat status neural network molten steel temperature prediction

Memway:In-Memory Waylaying Acceleration for Practical Rowhammer Attacks Against Binaries

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Tsinghua Science and Technology 2019年第5期24卷 535-545页

作者： Lai Xu Rongwei Yu Lina Wang Weijie Liu the Key Laboratory of Aerospace information Security and Trusted Computing Ministry of Education School of Cyber Science and Engineering Wuhan University

The Rowhammer bug is a novel micro-architectural security threat, enabling powerful privilege-escalation attacks on various mainstream platforms. It works by actively flipping bits in Dynamic Random Access Memory(DRAM) cells with unprivileged instructions. In order to set up Rowhammer against binaries in the Linux page cache, the Waylaying algorithm has previously been proposed. The Waylaying method stealthily relocates binaries onto exploitable physical addresses without exhausting system memory. However, the proof-of-concept Waylaying algorithm can be easily detected during page cache eviction because of its high disk I/O overhead and long running time. This paper proposes the more advanced Memway algorithm, which improves on Waylaying in terms of both I/O overhead and speed. Running time and disk I/O overhead are reduced by 90% by utilizing Linux tmpfs and inmemory swapping to manage eviction files. Furthermore, by combining Memway with the unprivileged posix fadvise API, the binary relocation step is made 100 times faster. Equipped with our Memway+fadvise relocation scheme,we demonstrate practical Rowhammer attacks that take only 15–200 minutes to covertly relocate a victim binary,and less than 3 seconds to flip the target instruction bit.

关键词： Rowhammer bug Waylaying algorithm in-memory swapping page cache eviction