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Cryptanalysis of a Key Exchange Protocol Based on Commuting Matrices

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Chinese Journal of Electronics 2017年第5期26卷 947-951页

作者： JIA Jianwei liu jinhui ZHANG Huanguo Computer School of Wuhan University Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education

A key exchange protocol is considered *** scheme is based on a set of m commuting square singular matrices of dimension n×n over a finite field,and its security is claimed to rely on the hardness of the matrix version discrete logarithm ***,the proposal’s design allows for a clean attack *** show that the key exchange protocol is vulnerable to a linear algebra attack which only requires polynomial time to obtain the equivalent keys for all given public *** conduct a detailed analysis on the attack method and provide some improved suggestions on the key exchange protocol based on commuting matrices.

关键词： Cryptography Key exchange protocol Cryptanalysis Discrete logarithm problem Linear equations

Cryptanalysis of Cryptosystems Based on General Linear Group

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China Communications 2016年第6期13卷 217-224页

作者： Jianwei Jia jinhui liu Huanguo Zhang Computer School of Wuhan University WuhanHubei 430072China Key Laboratory of Aerospace Information security and trusted computing Ministry of Education Wuhan UniversityWuhan 430072HubeiProvinceChina

Advances in quantum computers threaten to break public key cryptosystems such as RSA, ECC, and EIGamal on the hardness of factoring or taking a discrete logarithm, while no quantum algorithms are found to solve certain mathematical problems on non-commutative algebraic structures until now. In this background, Majid Khan et *** two novel public-key encryption schemes based on large abelian subgroup of general linear group over a residue ring. In this paper we show that the two schemes are not secure. We present that they are vulnerable to a structural attack and that, it only requires polynomial time complexity to retrieve the message from associated public keys respectively. Then we conduct a detailed analysis on attack methods and show corresponding algorithmic description and efficiency analysis respectively. After that, we propose an improvement assisted to enhance Majid Khan's scheme. In addition, we discuss possible lines of future work.

关键词： cryptography post quantum computational cryptography cryptanalysis non-abelian algebraic structures linear equations

Research, development and application of compound-vertical-retort technology for magnesium production

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Journal of Magnesium and Alloys 2023年第12期11卷 4724-4736页

作者： Rongbin Li Shaojun Zhang Peixu Yang jinhui liu Fengqin liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Material Science and Engineering Zhengzhou UniversityZhengzhouHenan 450001China

This paper comprehensively introduces a new magnesium production technology the compound-vertical-retort technology, involving in the related fundamental researches, core equipment development, working flow, and technical characteristics. Scale-up test and an annual1200-ton-magnesium demonstration-level test was conducted to confirm the rationality, reliability, and advancement of the equipment, system and process design. It is indicated that the new technology solved a series of problems of traditional silicothermic process including adhesion and glaze, short life of retort, low efficiency, high impurity of crystallized magnesium, large heat losses, and poor working environment,making a great technological breakthrough in this field. Representatively, the new well-designed ceramic-lined steel retort serves 2~3 times in life than the normal retorts. The magnesium yield per retort is improved 4~5 times, with purity of >99.8%. The energy consumption in reduction stage is reduced by more than 20%. The mechanical production is fully realized and operating environment is significantly improved.

关键词： Silicothermic process Magnesium Compound retort Vertical retort Mechanization

Model test and numerical simulation on the dynamic stability of the bedding rock slope under frequent microseisms

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Earthquake Engineering and Engineering Vibration 2020年第4期19卷 919-935页

作者： Deng Zhiyun liu Xinrong liu Yongquan liu Shulin Han Yafeng liu jinhui Tu Yiliang School of Civil Engineering Chongqing UniversityChongqing 400045China National Joint Engineering Research Center for Prevention and Control of Environmental Geological Hazards in the TGR Area Chongqing University Chongqing 400045China China Construction Underground Space Co. Ltd.Chengdu 610081China School of civil engineering Chongqing Jiaotong UniversityChongqing 400074China

Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability under purely microseisms and the influence of five factors, including seismic amplitude, slope height, slope angle, strata inclination and strata thickness, were considered. The experimental results show that the natural frequency of the slope decreases and damping ratio increases as the earthquake loading times increase. The dynamic strength reduction method is adopted for the stability evaluation of the bedding rock slope in numerical simulation, and the slope stability decreases with the increase of seismic amplitude, increase of slope height, reduction of strata thickness and increase of slope angle. The failure mode of a mid-dip bedding rock slope in the shaking table test is integral slipping along the bedding surface with dipping tensile cracks at the slope rear edge going through the bedding surfaces. In the numerical simulation, the long-term stability of a mid-dip bedding slope is worst under frequent microseisms and the slope is at risk of integral sliding instability, whereas the slope rock mass is more broken than shown in the shaking table test. The research results are of practical significance to better understand the formation mechanism of reservoir landslides and prevent future landslide disasters.

关键词： bedding rock slope frequent microseisms shaking table test numerical simulation dynamic stability failure mode long-term stability

SIV:A Structural Integrity Verification Approach of Cloud Components with Enhanced Privacy

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Tsinghua Science and Technology 2019年第5期24卷 557-574页

作者： Bo Zhao Peiru Fan Pengyuan Zhao Mingtao Ni jinhui liu School of Cyber Scienee and Engineering. Wuhan University Wuhan 430072 China. School of Computer Science Shaanxi Normal University Xi'an 710062 China

Private data leakage is a threat to current integrity verification schemes of cloud components. To address this issue, this work proposes a privacy-enhancing Structural Integrity Verification (SIV) approach. It is made up of three processes: proof organization, proof transformation, and integrity judgement. By introducing a Merkle tree technique, the integrity of a constituent part of a cloud component on a node is represented by a root value. The value is then masked to cipher texts in proof transformation. With the masked proofs, a structural feature is extracted and validated in an integrity judgement by a third-party verification provider. The integrity of the cloud component is visually displayed in the output result matrix. If there are abnormities, the corrupted constituent parts can be located. Integrity is verified through the encrypted masked proofs. All raw proofs containing sensitive information stay on their original nodes, thus minimizing the attack surface of the proof data, and eliminating the risk of leaking private data at the source. Although some computations are added, the experimental results show that the time overhead is within acceptable bounds.

关键词： integrity verification cloud components structural feature privacy

Actively tunable sandwich acoustic metamaterials with magnetorheological elastomers

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Applied Mathematics and Mechanics(English Edition) 2024年第11期45卷 1875-1894页

作者： jinhui liu Yu XUE Zhihong GAO A.O.KRUSHYNSKA Jinqiang LI College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin150001China Engineering and Technology Institute of Groningen(ENTEG) University of GroningenGroningen9700 ABThe Netherlands

Sandwich structures are widespread in engineering applications because of their advantageous mechanical ***,their acoustic performance has also been improved to enable attenuation of low-frequency vibrations induced by noisy ***,we propose a new design of sandwich plates(SPs)featuring a metamaterial core with an actively tunable low-frequency *** core contains magnetorheological elastomer(MRE)resonators which are arranged periodically and enable controlling wave attenuation by an external magnetic *** analytically estimate the sound transmission loss(STL)of the plate using the space harmonic expansion *** low frequency sound insulation performance is also analyzed by the equivalent dynamic density method,and the accuracy of the obtained results is verified by finite-element *** results demonstrate that the STL of the proposed plate is enhanced compared with a typical SP analog,and the induced bandgap can be effectively tuned to desired *** study further advances the field of actively controlled acoustic metamaterials,and paves the way to their practical applications.

关键词： sandwich plate(SP) magnetorheological elastomer(MRE) sound transmission loss(STL) vibration control acoustic metamaterial

Measuring Thermal Conductivity of an Individual Carbon Nanotube Using Raman Spectroscopy

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Journal of Thermal Science 2022年第4期31卷 1016-1022页

作者： LI Pei FENG Daili FENG Yanhui liu Xiaofang XIONG Mengya ZHANG Xinxin liu jinhui School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Energy Saving and Emission Reduction for Metallurgical Industry University of Science and Technology BeijingBeijing 100083China Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China

In this paper,a non-contact method based on Raman spectroscopy was used to measure the thermal conductivity of an individual single-walled carbon nanotube(SWCNT)and a multi-walled carbon nanotube(MWCNT).The effect of laser-induced heating on carbon nanotubes(CNTs)was *** local temperatures along the longitudinal direction of carbon nanotube were determined by Raman shift,combined with one-dimensional heat conduction model,and the thermal conductivity was finally *** thermal conductivity of the SWCNT with a length of 25μm and a diameter of 1.34 nm decreases as the temperature increases in the measuring temperature range(316 K–378 K).The corresponding thermal conductivities change from 1651 W/(m·K)to 2423 W/(m·K);the thermal conductivities of the MWCNT with 40μm length and 9.2 nm diameter are within 1109–1700 W/(m·K)at 316 K–445 *** further analyze the size effect on the thermal conductivity,molecular dynamics simulation has been carried *** result shows that the thermal conductivity of an individual carbon nanotube increases with increasing nanotube length and eventually *** work is expected to provide some reference data for the studies of thermal properties of individual CNTs.

关键词： carbon nanotube thermal conductivity Raman spectroscopy molecular dynamics

An investigation on micro pore structures and the vapor pressure mechanism of explosive spalling of RPC exposed to high temperature

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Science China(Technological Sciences) 2013年第2期56卷 458-470页

作者： JU Yang liu HongBin TIAN KaiPei liu jinhui WANG Li GE ZhiShun State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete China University of Mining and Technology School of Mechanics and Civil Engineering China University of Mining and Technology

Reactive powder concrete （RPC） is vulnerable to explosive spalling when exposed to high temperature. The characteristics of micro pore structure and vapor pressure of RPC are closely related to the thermal spalling. Applying mercury intrusion po- rosimetry （MIP） and scanning electron microscopy （SEM） techniques, the authors probed the characteristics of micro pore structures of plain RPC200 when heated from 20-350~C. The pore characteristics such as specific pore volume, threshold pore size and most probable pore size varying with temperatures were investigated. A vapor pressure kit was developed to measure the vapor pressure and its variation inside RPC200 at various temperatures. A thin-wall spherical pore model was proposed to ana- lyze the thermo-mechanical mechanism of spalling, by which the stresses varying with the vapor pressure q（T） and the character- istic size of wall （K） at any point of interest were determined. It is shown that the pore characteristics including specific pore volume, average pore size, threshold pore size and most probable pore size rise significantly with the increasing temperature. 200~C appears to be the threshold temperature above which the threshold pore size and the most probable pore size climb up dramatically. The increase in the specific pore volume results from the growth both in quantity and in volume of the transition pores and the capillary pores. The appearance of the explosive spalling in RPC200 is mainly attributed to being unable to form pathways in favor of releasing water steam in RPC and to thin-wall sphere domain where the vapor pressure governs the the rapid accumulation of high vapor pressures as well. The spalling is bounded through the pore model.

关键词： reactive powder concrete (RPC) high temperature spalling pore structure vapor pressure microstructures mercuryintrusion porosimetry (MIP)

A public key cryptosystem based on data complexity under quantum environment

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Science China(Information Sciences) 2015年第11期58卷 48-58页

作者： WU WanQing ZHANG HuanGuo WANG HouZhen MAO ShaoWu JIA JianWei liu jinhui Computer School Wuhan University

Since the Shor algorithm showed that a quantum algorithm can efficiently calculate discrete logarithms and factorize integers, it has been used to break the RSA, EIGamal, and ECC classical public key cryptosystems. This is therefore a significant issue in the context of ensuring communication security over insecure channels. In this paper, we prove that there are no polynomial-size quantum circuits that can compute all Boolean functions(of which there are 22ncases) in the standard quantum oracle model. Based on this,we propose the notion of data complexity under a quantum environment and suggest that it can be used as a condition for post-quantum computation. It is generally believed that NP-complete problems cannot be solved in polynomial time even with quantum computers. Therefore, a public key cryptosystem and signature scheme based on the difficulty of NP-complete problems and the notion of data complexity are presented here. Finally,we analyze the security of the proposed encryption and signature schemes.

关键词： public key cryptography information security NP-complete problem complexity theory quantum computation