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Fault attacks on hyperelliptic curve discrete logarithm problem over binary field

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Science China(Information Sciences) 2014年第3期57卷 187-203页

作者： WANG MingQiang XUE HaiYang zhan.tao School of Mathematics Shandong University

In this paper,we present invalid-curve attacks that apply to the hyperelliptic curve scalar multiplication(HECSM)algorithm proposed by Avanzi et *** the genus 2 hyperelliptic curve over binary *** observe some new properties of the *** attacks are based on these new properties and the observation that the parameters f0and f1of the hyperelliptic curve equation are not utilized for the *** show that with diferent"values"for curve parameters f0,f1,there exsit cryptographically weak groups in the Koblitz hyperelliptic ***,we compute the theoretical probability of getting a weak Jacobian group of hyperelliptic curve whose cardinality is an smooth integer.

关键词： hyperelliptic curve discrete logarithm binary field genus cryptosystem

A fractional differential constitutive model for dynamic stress intensity factors of an anti-plane crack in viscoelastic materials

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Acta Mechanica Sinica 2014年第3期30卷 403-409页

作者： Run-tao zhan.Zhao-Xia Li Lei Wang Department of Engineering Mechanics Southeast UniversityJiangsu Key Laboratory of Engineering Mechanics School of Civil Engineering Southeast University

Fractional differential constitutive relationships are introduced to depict the history of dynamic stress inten- sity factors （DSIFs） for a semi-infinite crack in infinite viscoelastic material subjected to anti-plane shear impact load. The basic equations which govern the anti-plane deformation behavior are converted to a fractional wave-like equation. By utilizing Laplace and Fourier integral transforms, the fractional wave-like equation is cast into an ordinary differential equation （ODE）. The unknown function in the solution of ODE is obtained by applying Fourier transform directly to the boundary conditions of fractional wave-like equation in Laplace domain instead of solving dual integral equations. Analytical solutions of DSIFs in Laplace domain are derived by Wiener-Hopf technique and the numerical solutions of DSIFs in time domain are obtained by Talbot algorithm. The effects of four parameters α, β, b1, b2 of the fractional dif- ferential constitutive model on DSIFs are discussed. The numerical results show that the present fractional differential constitutive model can well describe the behavior of DSIFs of anti-plane fracture in viscoelastic materials, and the model is also compatible with solutions of DSIFs of anti-plane fracture in elastic materials.

关键词： Dynamic fracture Stress intensity factors Fractional differentiation - Anti-plane fracture Viscoelasticmaterial Wiener-Hopf

Analysis of PROFIBUS-DP Network Delay and Its Influence on the Performance of Control Systems

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 877-882页

作者： tao Jun WANG zhan.lin School of Automation Science Beihang University Beijing 100083 China

This paper analyzes PROFIBUS-DP network delay in detail and presents the calculational formula of its maximum time-delay, which is significant to the research of PROFIBUS-DP. At the same time, the paper puts forward a method of simplifying the network induced time-varying indeterminate system according to the features of the network. Through the analysis of a pump-control-motor system which is composed of PROFIBUS-DP network, it illustrates the network＇s influence on the performance of control systems. This method helps to design and analyze the network＇s influence on the performance of control systems, which is of considerable practical value in a time when network control systern is widely used.

关键词： network delay analysis network control system deterministic control

Rate allocation strategies for energy-efficient multipath routing in Ad-hoc networks towards B3G

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 84-88页

作者： zhan.Song-tao XU Guo-xin Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless mobile Ad-hoc network is a special network that all nodes can serf-organize and work together. It is flexible to form a network and extend the coverage area dynamically without infrastructure, so Ad-hoc network is envisioned as cornerstones of future generation networking technologies （B3G or 4（3）. However, the dynamic network topology makes the communication cost not only the energy of source/destination nodes, but also the relay nodes. Another problem of the Ad-hoc network is it is hard to provide a stable and persistent quality of service （QoS）, which is strongly required by the beyond 3rd generation （B3G） system. In this article, the authors establish a scenario that contains B3G cellular base station and Ad-hoc mobile nodes, and propose two algorithms minimum incremental rate algorithm and power feed-back rate allocation algorithm in multipath routing. The algorithms can maintain a constant total transmission rate and bit error ratio （BER） to provide the QoS guarantee and reach the minimum power consumption of the relay nodes by adjusting the rate of each path in the multipath routing.

关键词： Ad-hoc network B3G multipath routing energy consumption QoS

Effects of Process Parameters on the Temperature Field in Ti-6Al-4V Alloy Blade Precision Forging Process

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Journal of Materials Science & Technology 2006年第4期22卷 473-477页

作者： Yuli LIU He YANG tao GAO Mei zhan College of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

Blade precision forging is a high temperature and large plastic deformation process. Process parameters have a great effect on temperature distribution in billet, so in this paper, by taking a Ti-6Al-4V alloy blade with a tenon as an object, the influence of process parameters on the temperature distribution in precision forging process was investigated using 3D coupled thermo-mechanical FEM （finite element method） code developed by the authors. The results obtained illustrate that：（1） the gradient of temperature distribution increases with increasing the deformation degree; （2） with increasing the initial temperature of the billet, the zones of high temperature become larger, and the gradient of temperature distribution hardly has any increase; （3） friction factors have little effect on the distribution of temperature field; （4） with increasing upper die velocity, temperature of the billet increases while the temperature gradient in billet decreases. The results are helpful to the design and optimization of the process parameters in precision forging process of Ti-alloy blade.

关键词： Ti-alloy blade Precision forging Process parameter Temperature field Finite element method (FEM)

Momentum Transfer of an Atom Moving in an Optical Cavity

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Chinese Physics Letters 2001年第8期18卷 1069-1071页

作者： zhan. Jing-tao XU Zhi-zhan Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

When an atom moves in an optical cavity,the total momentum of the atom does not keep *** study a two-level atom moving slowly in an optical cavity,and give the time dependence of its mean *** is found that when the initial momentum of the atom is larger than that of the photon,the mean momentum oscillates around a value less than the initial value,But,if the initial momentum is less than the momentum of the photon,the mean momentum of the atom is greater than its initial value in most time.

关键词： momentum value initial

Experiment on Boiling Heat Transfer of Refrigerant R134a in Mini-channels

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第1期36卷 80-87页

作者： zhan.Hongbo SHEN Hao WEN tao zhan. Dalin College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Shanghai Aircraft Airworthiness Certification Center of CAAC

The flow boiling heat transfer characteristics of refrigerant R134 a flowing inside two different kinds of minichannels are investigated. One channel is multi-port extruded with the hydraulic diameter of 0.63 mm,and the other one is rectangular with offset fins and a hydraulic diameter of 1.28 mm. The experiments are performed with a mass flow rate between 68 and 630 kg/(m^2·s),a heat flux between 9 and 64 kW/m^2,and a saturation pressure between 0.24 and 0.63 MPa,under the constant heat flux heating mode. It is found that the effect of mass flow rate on boiling heat transfer is related to heat flux,and that with the increase of heat flux,the effect can only be efficient in higher vapor quality region. The effects of heat flux and saturation pressure on boiling heat transfer are related to a threshold vapor quality,and the value will gradually decrease with the increase of heat flux or saturation pressure. Based on these analyses,a new correlation is proposed to predict the boiling heat transfer coefficient of refrigerant R134 a in the mini-channels under the experimental conditions.

关键词： flow boiling heat transfer two-phase flow refrigerant R134a channels with offset fins multi-portchannel

TEMPERATURE SENSITIVITY AND PREDICTION OF THE MECHANICAL BEHAVIORS OF ULTRAFINE GRAINED ALUMINUM UNDER UNIAXIAL COMPRESSION

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Acta Mechanica Solida Sinica 2014年第4期27卷 373-382页

作者： Quanwei zhan.tao Suo Cunxian Wang Kui Xie Zhongbin Tang Institute of UAV research Northwestern Polytechnical University School of Aeronautics Northwestern Polytechnical University Department of Mechanical Engineering The Johns Hopkins University 3400 N. Charles StreetBaltimore MD 21218 USA China Electronics Technology Group Corporation No.38 Research Institute

In the present work, we explore the strain hardening behaviors as well as the effect of temperature on the plastic deformation of ultrafine grained aluminum. The temperature sensitivity is determined and compared with that of coarse grained material. The results indicate that the flow stress of ultrafine grained aluminum displays enhanced sensitivity to temperature. The reduction in activation volume is suggested to be the major reason for the enhanced temperature sensitivity as grain size is refined into the sub-micrometer regime. Finally, a phenomenological constitutive model is proposed to describe the post-yield response of ultrafine grained aluminum.

关键词： ultrafine grained aluminum compressive behavior temperature sensitivity strain hardening behavior constitutive relation

Multiple teleportation via partially entangled GHZ state

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Frontiers of physics 2016年第4期11卷 101-108页

作者： Pei-Ying Xiong Xu-tao Yu Hai-tao zhan.Zai-Chen zhan. State Key Lab of Millimeter Waves Southeast University Nanjing 210096 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

Quantum teleportation is important for quantum comrmmication. We propose a protocol that uses a partially entangled Greenberger-Horne-Zeilinger （GHZ） state for single hop teleportation. Quantum teleportation will succeed if the sender makes a Bell state measurement, and the receiver performs the Hadamard gate operation, applies appropriate Pauli operators, introduces an auxiliary particle, and applies the corresponding unitary matrix to recover the transmitted state. We also present a protocol to realize multiple teleportation of partially entangled GHZ state without an auxiliary particle. We show that the success probability of the teleportation is Mways [） when the number of teleportat, ions is odd. In order to improve the success probability of a multihop, we introduce the method used in our single hop teleportation, thus proposing a multiple teleportation protocol using anxiliary particles and a unitary matrix. The final success probability is shown to bc improved significantly for the method without auxiliary particles fbr both an odd or even number of teleportations.

关键词： auxiliary particle partially entangled GHZ state multiple teleportation protocol