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Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2.WEN QiaoYan3 & ZHANG Xing4,5 1 college of Computer Science and technology,{2. university of technology,{2. 10002.,china 2.State Key Laboratory of Information Security (Graduate university of the Chinese Academy of Sciences),{2. 100049,china 3 School of Science,{2. university of Posts and Telecommunications,{2. 100876,china 4 Institute of Electronic technology,Information Engineering university,Zhengzhou 450004,china 5 Trusted Computing Laboratory,{2. university of technology,{2. 10002.,china college of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (Graduate university of the Chinese Academy of Sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China Institute of Electronic technology Information Engineering University Zhengzhou China Trusted Computing Laboratory Beijing University of Technology Beijing China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Mathematical stencil and its application in finite difference approximation to the Poisson equation

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Science china Mathematics 2005年第10期48卷 1421-1429页

作者： FENG Hui~1 ZHANG Baolin~(1,2. & LIU Yang~1 1. Department of Mathematics,Wuhan university,Wuhan 430072.china 2. Laboratory of Computational Physics,Institute of {2. Physics and Computational Mathematics,beijing 100088. china Department of Mathematics Wuhan University Wuhan China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing China

The concept of mathematical stencil and the strategy of stencil elimination for solving the finite difference equation is presented, and then a new type of the iteration algorithm is established for the Poisson equation. The new algorithm has not only the obvious property of parallelism, but also faster convergence rate than that of the classical Jacobi iteration. Numerical experiments show that the time for the new algorithm is less than that of Jacobi and Gauss-Seidel methods to obtain the same precision, and the computational velocity increases obviously when the new iterative method, instead of Jacobi method, is applied to polish operation in multi-grid method, furthermore, the polynomial acceleration method is still applicable to the new iterative method.

关键词： mathematical stencil, stencil elimination, Poisson equation, finite difference, iterative algorithm,parallelism.

Global convergence property of s-dependent GFR conjugate gradient method

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Chinese Science Bulletin 1998年第23期43卷 1959-1965页

作者： WANG Changyu 1,2.and ZHANG Yuzhong\+1 1. Institute of Operations Research in Qufu Normal university, Qufu 2.3165, china 2. Institute of {2. Mathematics, Chinese Academy of Sciences, beijing 100080, china Institute of Operations Research Qufu Normal University Qufu China Institute of applied Mathematics Chinese Academy of Sciences Beijing China

An \%S\%_dependent GFR method and a generalized conjugate gradient method are designed. Two estimated values of upper bounds for the ratio of β k to β FR k are given. The two convergence theorems are proved. The global convergent properties of \%s\%_dependent GFR method are obtained adopting several choice strategies of steplength and some results in recent literature are extended.

关键词： steplength linear search global convergence conjugate gradient.

Surface Nanocrystallization of Magnesium Alloy AZ91D by High-Energy Shot Peening

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Journal of Wuhan university of technology(Materials Science) 2009年第4期24卷 515-519页

作者：张津 School of Materials Science & Engineering University of Science and Technology Beijing college of Materials Science & Engineering Chongqing University of Technology

High-energy shot peening （HESP）, a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESP and heat treatment at different temperatures were investigated. The mi- crostructure evolution was conducted using X-ray diffraction （XRD） and field emission scanning electronic microscopy （FESEM）. The hardness was measured by microhardness tester. The experimental results show that surface nanocrystrallization of AZ91D obtained by HESP would lead to the increase of microhardness. Low temperature heated at 100℃ for 1 h do not change the property obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400℃ for 1 h.

关键词： AZ91 D surface nanocrystallization HESP microhardnss corrosion resistance

Numerical simulation of strain localization and damage evolution in large plastic deformation using mixed finite element method

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Journal of university of Science and technology {2. 2004年第3期11卷 273-277页

作者： Zhanghua Chen Jiajian Jin Jiumei Xiao applied Science School, university of Science and {2. beijing, beijing 100083, china applied Science School University of Science and Technology Beijing Beijing 100083 China

An investigation of computer simulation is presented to analyze the effectsof strain localization and damage evolution in large plastic deformation. The simulation is carriedout by using an elastic-plastic-damage coupling finite element program that is developed based onthe concept of mixed interpolation of displacement/pressure. This program has been incorporated intoa damage mechanics model as well as the corresponding damage criterion. To illustrate theperformance of the proposed approach, a typical strain localization problem has been simulated. Theresults show that the proposed approach is of good capability to capture strain localization andpredict the damage evolution.

关键词： strain localization mixed element truesdell stress rate material damage

A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, beijing 100044, china 2. {2. of Earth Sciences and Resources, china university of Geo-sciences, beijing 100083, china Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China college of Earth Sciences and Resources China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

Photocatalytic degradation of formaldehyde by diffuser of solar light pipe coated with nanometer titanium dioxide thin films

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Science china(Technological Sciences) 2010年第1期53卷 150-154页

作者： WU YanPeng1,ZHANG WenMing1,MA ChongFang2.LU YuanWei2.& LIU Li1 1 School of Civil and Environmental Engineering,university of Science and technology {2.,{2. 100083,china 2.college of Environmental and Energy Engineering,{2. university of technology,{2. 10002.,china School of Civil and Environmental Engineering University of Science and Technology Beijing

The even and transparent nanometer TiO2.thin films named DegussaP2. as photocatalysis deposited on the surface of diffusers of solar light pipe were prepared by sol-gel *** rugged side of the diffusers of solar light pipe was coated evenly with DegussaP2. solution for the quality of 1.75 *** experiments had showed that when the coated side was away from the sun the lighting degree may be reduced compared with that facing the *** average reduction was only 3.03%,which would not have a significant impact on *** are important parts of a light pipe which can diffuse light evenly to the place needed to be *** experiments showed that in a sunny summer day under the direct sunlight,the solar light pipe combined with photocatalysis could reduce the formaldehyde volume fraction in a box of 0.1 m3 from 1.0×10-6 to 0.16×*** 1 h of photodegradation the formaldehyde volume changed from 1.0×10-6 down to 0.1×10-6 with faster and more complete degradation of *** rate of degradation under cloudy and partly cloudy conditions was slower than that under sunny *** was slower in winter than in summer under sunny *** experimental results also showed that the performance of photocatalysis combined with diffusers of light pipe had better effect in a small *** performance in large space,such as open space,will be the next work in the future,which will be a great challenge.

关键词： solar light pipes diffusers photocatalysis decomposition formaldehyde titanium dioxide

Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 773-780页

作者： LI LianHe1,2.& FAN TianYou1 1 Department of Physics, beijing Institute of technology, beijing 100081, china 2.college of Mathematics Science, Inner Mongolia Normal university, Hohhot 01002., china Department of Physics Beijing Institute of Technology Beijing China college of Mathematics Science Inner Mongolia Normal University Hohhot China

The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.

关键词： icosahedral quasicrystals plane elasticity elliptic notch complex variable method

Representations of Real and Complex Stability Radii of 2.Dimensional LinearSystems

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 299-301页

作者： Lequan Min1.2.Ning Song1(l applied Science School, university of Science and {2.’ beijing, beijing 100083, china2.5} Center of Advanced Science and {2., beijing 100080, china) applied Science School University of Science and Technology Beijing Beijing 100083 China china Center of Advanced Science and technology Beijing 100080 China

Rigorous proofs are given for the representations of real and complex stability' radii of 2.dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2.dimensional linear system under pelturbation of the system parameters, in particular testing the effect of numerical algorithms which are used to calculate the real stability radii of higher dimensional piecewise-linear systems.

关键词： linear systems robustness stability radii