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Collision Attacks against AEZ-PRF for Authenticated Encryption AEZ

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China Communications 2018年第2期15卷 46-53页

作者： Tairong Shi Chenhui jin Jie guan Information Science and Technology Institute Science Avenue High-Tech Zone Zhengzhou Henan 450001 China

AEZ is an AES-based authenticated encryption submitted to the ongoing CAESAR competition and was presented at Eurocrypt2015 with AEZ v3. There are three models for AEZ, AEZ-core, AEZ-tiny and AEZ-prf. In this paper, we consider the security of AEZprf for AEZ v4.2, the latest version of *** major finding is a collision of any 256-bit associated data for AES-prf. Then we launch collision attacks in a quantum setting and a classical setting respectively under different assumptions. In the quantum setting, by Simon's quantum algorithm, we amount a forgery with O(n) quantum superposition queries and an overwhelming probability close to *** the classical setting, one with the key of AEZ-prf can also construct the forgeries. Our results show that the AEZ-prf models of AEZ v4.2 is not secure in both the quantum setting and classical world. Furthermore, our results can also be applied to AEZ v3, which has been published on Eurocrypt 2015. As far as we know, no cryptanalysis of AEZ v4.2 has been published so far.

关键词： CAESAR competition authen-ticated encryption AEZ collision attacks quantum attacks

On Moments of the Maximum of Partial Sums of Moving Average Processes under Dependence Assumptions

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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 691-696页

作者： Xing-cai ZHOU jin-guan LIN Department of Mathematics Southeast University Nanjing 210096 China Department of Mathematics and Computer Science Tongling University Tongling 244000 China

Let{Yi;-∞〈i〈∞}be a doubly infinite sequence of identically distributed φ-mixing random variables and let{ai;-∞〈i〈∞}be an absolutely summable sequence of real numbers. In this paper we study the moments of su... 详细信息

关键词： Moving average φ-mixing Moments

An aerospace bracket designed by thermo-elastic topology optimization and manufactured by additive manufacturing

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Chinese Journal of Aeronautics 2020年第4期33卷 1252-1259页

作者： guanghui SHI Chengqi guan Dongliang QUAN Dongtao WU Lei TANG tong GAO Beijing Aerospace Technology Institute Beijing 100074China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi'an 710072China Institute of Intelligence Material and Structure Unmanned System TechnologiesNorthwestern Polytechnical UniversityXi'an 710072China

Combination of topology optimization and additive manufacturing technologies provides an effective approach for the development of light-weight and high-performance structures.A heavy-loaded aerospace bracket is designed by topology optimization and manufactured by additive manufacturing technology in this *** both mechanical forces and temperature loads,a formulation of thermo-elastic topology optimization is firstly proposed and the sensitivity analysis is derived in *** the procedure of numerical optimization design is presented and the final design is additively manufactured using Selective Laser Melting(SLM).The mass of the aerospace bracket is reduced by over 18%,benefiting from topology and size optimization,and the three constraints are satisfied as well in the final *** work indicates that the integration of thermo-elastic topology optimization and additive manufacturing technologies can be a rather powerful tool kit for the design of structures under thermal-mechanical loading.

关键词： Additive manufacturing Aerospace bracket Selective laser melting(SLM) Thermo-elastic Topology optimization

Deformation efficiency, homogeneity, and electrical resistivity of pure copper processed by constrained groove pressing

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Rare Metals 2014年第3期33卷 287-292页

作者： Zong-Shen Wang Yan-jin guan Ping Liang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University

Constrained groove pressing（CGP） is a new severe plastic deformation method suitable for producing ultra-fine grained sheet metals. In this work, the processing efficiency for a muti-pass CGP of pure copper was investigated. With a relatively small groove width of 2 mm and tight constraint, a sharp variation of mechanical properties with pass number is observed. Subgrains with the size of＊0.5 lm have distinct boundaries, which is the predominant feature in the microstructure after three passes. The evolution of deformation homogeneity characterized by micro-hardness distribution was examined in *** of optical micrographs and fracture surface morphology confirm the evolution rule. The relation between electrical resistivity and accumulative plastic strain was discussed. Crystalline defects, micro-cracks, and microstructure uniformity together determine the change of electrical resistivity of CGP copper.

关键词： Constrained groove pressing Processingefficiency Strain homogeneity Electrical resistivity

STUDY ON THE STRUCTURE AND PROPERTIES OF HIGH CHROMIUM WHITE CAST IRON AND ITS TEMPERING STANDARD

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Journal of Central South University 1999年第1期11卷 9-13页

作者： Yingfeng guan Zhanpeng jin 1. Department of Materials Science and Engineering Central South University of Technology 410083 Changsha China

The structure and properties of high chromium white cast iron in different treatment states were studied. Using X ray diffraction method, observing their metallograph and measuring their microhardness, the phases involved in the iron were determined. The notch toughness, macrohardness and the fractograph of the samples are compared and their performance was determined, which mainly depends on the matrix structure. Relatively good comprehensive properties can be obtained in the tempering state. Improvements have been made on the commonly used tempering standard. Tempering for a short period at low temperature can improve the materials′ service performance obviously.

关键词： high chromium white cast iron structure property performance tempering

Robust Output Feedback Control for Fractional Order Nonlinear Systems with Time-varying Delays

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IEEE/CAA Journal of Automatica Sinica 2016年第4期3卷 477-482页

作者： Changchun Hua tong Zhang Yafeng Li Xinping guan Institute of Electrical Engineering Yanshan University Department of Automation Shanghai Jiao Tong University

Robust controller design problem is investigated for a class of fractional order nonlinear systems with time varying delays. Firstly, a reduced-order observer is designed. Then, an output feedback controller is designed. Both the designed observer and controller are independent of time delays. By choosing appropriate Lyapunov functions, we prove the designed controller can render the fractional order system asymptotically stable. A simulation example is given to verify the effectiveness of the proposed approach. © 2014 Chinese Association of Automation.

关键词： Algebra Backstepping Controllers Feedback Feedback control Lyapunov functions Nonlinear systems Robust control Time delay

Recycling combustibles from aged municipal solid wastes(MSW)to improve fresh MSW incineration in Shanghai:Investigation of necessity and feasibility

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Frontiers of Environmental Science & Engineering 2010年第2期4卷 235-243页

作者： Dezhen CHEN Zhenzhen guan guangyu LIU Gongming ZHOU tong ZHU Thermal&Environmental Engineering Institute Tongji UniversityShanghai 200092China National Engineering Research Center for Urban Pollution Control Tongji UniversityShanghai 200092China

Aged municipal solid wastes(MSW)excavated from landfills and dumpsites were characterized to analyze their fraction composition,moisture content,and lower heat value(LHV).The necessity and feasibility of recycling combustibles from aged MSW to improve the incineration of fresh MSW were *** results showed that combustibles in aged MSW were easily separated from other components and than LHV of the separated combustibles are higher than 11000 kJ/*** fresh MSW are of high moisture contents with average LHV below 6500 kJ/kg,making their stable combustion difficult to maintain in MSW *** both fresh MSW and aged MSW,plastics are the main contributor to their *** improve incineration of fresh MSW that are characterized with low LHV,combustibles separated from aged MSW were made into refuse derived fuel(RDF)pellets and were then added to fresh MSW by 2%wt.–5%*** variation and air supply resistance change of the MSW layer on the incinerator grate caused by the addition of RDF was checked,and no significant changes were *** obvious difference was observed for the‘burn-out time’between RDF pellets and fresh MSW *** made from aged MSW combustibles is found to be a promising auxiliary fuel to improve the incineration of fresh MSW,and aged MSW from old landfill cells and dumpsites can be finally disposed of jointly with fresh MSW by recycling combustible from the former to be coincinerated with the latter in the incineration plants.

关键词： aged municipal solid wastes(MSW) fresh MSW lower heat value(LHV) combustibles refuse derived fuel(RDF) incineration

Effect of Fumed SiO_2 on Pore Formation Mechanism and Various Performances of β-iPP Microporous Membrane Used for Lithium-ion Battery Separator

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Chinese Journal of Polymer Science 2018年第4期36卷 536-545页

作者： Lei Ding guan Xu Qian Ge tong Wu Feng Yang Ming Xiang State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University

In this work, four samples containing different contents of fumed SiO_2 were prepared to improve the pore size distribution and various properties of b nucleated isotatic polypropylene（b-i PP） biaxial membrane used for lithium-ion battery separator. The wide-angle X-ray diffraction（WAXD） and differential scanning calorimetry（DSC） results show that the fumed SiO_2 promotes the formation of b-crystal slightly and narrows down the thickness distribution of b-lamellae; meanwhile, evenly distributed SiO_2 within b-i PP can be inspected by scanning electron microscopy（SEM）. Moreover, further detailed characterization of morphological evolutions during biaxial stretching by tensile testing and SEM manifests that SiO_2 can strengthen b-i PP and make the samples deform more homogeneously, resulting in a gradually elaborate and finer oriented microfibril structure after longitudinal stretching, in which more uniform defects distribute between fibrils and restrain the formation of coarse fibrils effectively. Therefore, more superior microporous structure emerges with the addition of SiO_2, accompanied by narrower pore size distribution and better connectivity between microvoids, which is confirmed by mercury porosimeter and diminished Gurley value. Moreover, the lower thermal shrinkage, decreased shrinkage rate and suppressed porosity reduction indicate that fumed SiO_2 improves thermal and dimensional stability of membrane dramatically. Furthermore, due to the excellent wettability of SiO_2 with electrolyte, the microporous membranes doped with SiO_2 have higher electrolyte uptake, even after heat treatment at elevated temperature.

关键词： β Nucleated polypropylene Fumed SiO2 Microporous membrane Pore size distribution Thermal stability and wettability

Self-lubricating epoxy-based composite abradable seal coating eliminating adhesive transfer via hierarchical design

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Journal of Materials Science & Technology 2022年第9期104卷 145-154页

作者： Yun-qi tong Wei Li Qiu-sheng Shi Lin Chen guan-jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China

Aluminum-based composite abradable seal coatings are pivotal to improving the efficiency of aero engines or gas ***,the adhesive transfer frequently occurs between metallic blade tips and aluminum-based composite coatings,resulting in engine vibration and even *** past studies had tried to solve this problem by reducing coating hardness,improving lubrication,or strengthening blade tips,but all had *** this paper,we proposed a novel epoxy-based composite abradable seal coating,eliminating adhesive transfer by changing metal-to-metal scraping pair to metal-to-polymer scraping *** coating was developed via a hierarchical structure *** spherical pores were uniformly distributed in the continuous epoxy matrix with fine graphite *** adding 20 vol.%graphite and 50 vol.%hollow microspheres,a self-lubricating epoxy-based coating of 0.26 friction coefficient with thermal conductivity of 0.28 W/(m·K),coating HR15 Y hardness at 54.8,and bonding strength at 18.7 MPa can be *** the metallic blades scrape the epoxy-based composite coating,no adhesive transfer ***,a smooth scraped surface is formed by pseudoplastic *** epoxy-based composite abradable seal coating opens a new way to improve the efficiency and reliable operations of air engine compressors.

关键词： Epoxy-based composite coating Hierarchical structure design Self-lubricating Pseudoplastic deformation