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Two classes of rotation symmetric semi-bent functions

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Science China(Information Sciences) 2017年第6期60卷 263-265页

作者： Qinglan ZHAO dong zheng School of Information Security Engineering Shanghai Jiao Tong University National Engineering Laboratory for Wireless Security Xi'an University of Post and Telecommunications

Boolean functions play critical roles in modern *** the past decades,Boolean functions satisfying significant cryptographic properties(such as high nonlinearity and high algebraic immunity)have been studied[1,2].Semi-... 详细信息

关键词： In Two classes of rotation symmetric semi-bent functions Fn

Effect of removing Al and Ti elements on peak flow stress of nickel-based heat-resistant alloy 617

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Journal of Iron and Steel Research International 2023年第2期30卷 384-391页

作者： Chen dong zheng-zong Chen zheng-dong Liu Han-sheng Bao Zhen Liu zheng-jun Wang Faculty of Mechanical and Material Engineering Huaiyin Institute of TechnologyHuaian223003JiangsuChina Jiangsu Key Laboratory of Advanced Manufacturing Technology Huaiyin Institute of TechnologyHuaian223003JiangsuChina Institute for Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing100081China

The hot deformation behavior and the microstructure characteristics of alloy 617 and alloy C-HRA-2 were compared and *** removal of Al and Ti elements has a significant change in the hot deformation of the alloy,and there are two opposite effects on the flow stress before and after *** results show that the removal of Al and Ti elements increases the flow stress of the alloy under high temperature or low strain rate deformation *** is mainly due to the increase in the stacking fault energy of the alloy so that the alloy contains a higher twin boundary fraction after dynamic recrystallization(DRX).However,before DRX occurs,that is,at low temperature and high strain rate,the flow stress of this alloy is relatively *** is due to the reduction in Peierls-Nabarro stress,making the alloy more prone to dislocation slip.

关键词： Peak flow stress Nickel-based heat-resistant alloy Slip band Stacking fault energy

Hot deformation behavior of a heat-resistant alloy without γ′-phase

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Journal of Iron and Steel Research International 2020年第7期27卷 820-833页

作者： Chen dong zheng-dong Liu zheng-zong Chen Zhen Liu Jia-zhuang zheng Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Institute for Special Steels Central Iron and Steel Research InstituteBeijing100081China

The hot compression behavior of the nickel-based heat-resistant alloy C-HRA-2®was investigated by a Gleeble-1500 thermo-mechanical simulator with the deformation temperature range of 950-1150℃and the strain rate of 0.001-10 s^−*** constitutive equation of the alloy was established by using a hyperbolic sine function,and the peak stress followed a power law relationship with the Zener-Hollomon parameter(Z).The activation energy was about 446 kJ mol^−1 for the whole hot deformation domain in this *** optimum hot deformation condition was obtained in the temperature range of 1050-1150℃and the strain rate range of 0.005-0.1 s^−*** domains during the hot deformation would occur in the strain rate range of 0.1-10 s^−1 with inhomogeneous microstructure and high-density twins in the *** dominant nucleation mechanism of dynamic recrystallization(DRX)was continuous dynamic recrystallization with sub-grain rotation at high strain rate,while DRX at low strain rate was discontinuous dynamic recrystallization with original grain boundaries bulging.

关键词： Nickel-based alloy Dynamic recrystallization Hot compression Processing map

LCP method for a planar passive dynamic walker based on an event-driven scheme

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Acta Mechanica Sinica 2018年第3期34卷 578-588页

作者： Xu-dong zheng Qi Wang School of Aeronautic Science and Engineering Beihang University

The main purpose of this paper is to present a linear complementarity problem （LCP） method for a planar passive dynamic walker with round feet based on an event-driven scheme. The passive dynamic walker is treated as a planar multi-rigid-body system. The dynamic equations of the passive dynamic walker are obtained by using Lagrange＇s equations of the second kind. The normal forces and frictional forces acting on the feet of the passive walker are described based on a modified Hertz contact model and Coulomb＇s law of dry friction. The state transition problem of stick-slip between feet and floor is formulated as an LCR which is solved with an event-driven scheme. Finally, to validate the methodology, four gaits of the walker are simulated： the stance leg neither slips nor bounces; the stance leg slips without bouncing; the stance leg bounces without slipping; the walker stands after walking several steps.

关键词： Passive dynamic walker Non-smooth dynamics Dry friction Linear complementarity problem Stick-slip

On the performance of full-duplex non-orthonogal multiple access with energy harvesting over Nakagami-m fading channels

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High Technology Letters 2021年第4期27卷 337-346页

作者： Guo Weidong zheng dong School of Information Science and Engineering Shandong UniversityQingdao 266237P.R.China School of Cyber Science and Engineering Qufu Normal UniversityQufu 273165P.R.China

A cooperative full-duplex(FD)non-orthogonal multiple access(NOMA)network is consid-ered,in which a source communicate with multiple users via multiple energy harvesting(EH)FD *** on this structure,a novel relay selection scheme is proposed over Nakagamim fading channels by considering both the channel state information(CSI)and the energy statuses of relays.A finite Markov chain is adopted to capture the evolution of relay batteries and simplify the performance analysis by making some reasonable *** closed-form expressions of the outage probability and the ergodic sumrate are *** the theoretical results are validated by Monte-Carlo *** impacts of various system parameters,such as the number of relays,the self-interference(SI)at the involved relay and battery size,on the performance are extensively *** is shown that the usage of NOMA with FD relaying outperforms the half-duplex(HD)-NO-MA and conventional orthogonal multiple access(OMA)network when the self-interference is not too large.

关键词： non-orthogonal multiple access(NOMA) full-duplex(FD) energy harvesting(EH) Markov chain

Quantum Transport and Surface Scattering in Magnetic Metallic Film

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Communications in Theoretical Physics 2008年第9期50卷 771-776页

作者： HU Yin dong zheng-Chao Department of Physics Huaiyin Teachers College Huaian 223001 China Key Laboratory for Chemistry of Low-Dimensional Materials of Jiangsu Province Huaian 223001 China

Taking into account the quantum size effect and the spin dependence of the electronic band structure,and including the spin dependence of the scattering from bulk impurities and two different sets of surface roughness,wepresent a theory on the electronic transport in magnetic film,in which the average autocorrelation function (ACF) forsurface roughness is described by a Gaussion *** result shows that the conductivity is a sensitive function ofsurface roughness and exchange *** is also found that in the thin film limit and in the lower-order approximationof the surface scattering,the total conductivity is given by a sum of conductivities of all the subbands and the two spinchannels,for each subband and each spin channel the scattering rates due to the impurities and two surfaces are additive.

关键词： magnetic metallic film surface scattering magnetic exchange splitting

Effects of long term aging on microstructure and properties of a tungsten bearing heat resistant alloy

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Journal of Iron and Steel Research International 2020年第4期27卷 477-487页

作者： Han-sheng Bao Gang Yang zheng-zong Chen zheng-dong Liu Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The effects of long-term aging at 700 and 750℃ on microstructure and mechanical properties of a new developed tungsten bearing heat-resistant alloy used for advanced ultra-supercritical power plant was investigated both experimentally and *** results showed that the mechanical properties maintained excellent stability after long-term aging at 700℃ for 10,000h,while the impact absorbing energy decreased sharply after 1000-h aging and then kept constant till 10,*** main precipitates after long-term aging at 700 and 750℃ were M23C6,MC and homogeneous γ′-*** mass fraction of M23C6 carbides increased with increasing aging time,and M23C6 carbides precipitated in shape of chains and lamellas on grain *** slight decrease in MC carbides during aging may be due to degradation *** weight fraction of γ′-phase increased with the aging time,and then changed little after 5000h;γ′-phase exhibited excellent microstructure stability and low coarsening rate during long-term aging at 700℃.However,the coarsening rate of γ′-phase was much higher at 750℃.

关键词： Tungsten Long-term aging Heat-resistant alloy gama′-phase Coarsening rate

Preparation of TiB_2 coatings by electroplating in molten salt

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Rare Metals 2005年第3期24卷 261-266页

作者： LI Jun LI Bing dong zheng＇e School of Resource and Environment Engineering East China University of Science and Technology Shanghai 200237 China School of Materials Engineering Shanghai University of Engineering Science Shanghai 200336 China School of Textile Xi＇an Institute of Science and Technology Xi＇an 710048 China

Titanium diboride （TIB2） coatings were prepared by electroplating in fluoride-chloride electrolytes （KF-KC1） containing K2T1F6 and KBF4 as the electrochemically-active components. An attempt was made to correlate the thermodynamic prediction and experimental observations. Thick, adherent, and uniform TtB2 coatings were obtained and the coating microhardness reaches the value of 33 GPa. The effects of the current density on the mechanical properties, structures, and morphologies of the coatings were studied. XRD analysis indicates that the preferred orientation of the coatings is （001）, which is in accordance with the prediction of the two-dimensional crystal nuclei theory. Thermodynamic prediction and experimental results show that some phases such as TixCy and BaCb are absent at the interface, which indicates the substrate and coatings bind mechanically or physically. Some cracks exist at the interface, which is attributed to the difference between the coefficients of thermal expansion of TiB2 and graphite.

关键词： electrodeposition titanium diboride coatings molten salt

Constructing Odd-Variable Rotation Symmetric Boolean Functions with Optimal Algebraic Immunity and High Nonlinearity

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Chinese Journal of Electronics 2019年第1期28卷 45-51页

作者： ZHAO Qinglan HAN Gang zheng dong LI Xiangxue School of Information Security Engineering Shanghai Jiaotong University National Engineering Laboratory for Wireless Security Xi'an University of Post and Telecommunications College of Electronic Information Northwestern Polytechnical University School of Computer Science and Technology East China Normal University

Rotation symmetric Boolean functions(RSBFs) have attracted widespread attention due to their good cryptographic properties. We present a new construction of RSBFs with optimal algebraic immunity on odd number of variables. The nonlinearity of the new function is much higher than other best known RSBFs with optimal algebraic immunity. The algebraic degree of the constructed n-variable RSBF can achieve the upper bound n-1 when n/2 is odd or when n/2 is a power of 2 for n≥*** addition, the constructed function can possess almost perfect immunity to fast algebraic attacks for n=11, 13, 15.

关键词： Cryptography Boolean functions Algebraic immunity Nonlinearity Algebraic attack