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Multiparty simultaneous quantum identity authentication with secret sharing

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,beijing university of Technology,beijing 100022,china 2 state key laboratory of Information Security (Graduate university of the Chinese Academy of sciences),beijing 100049,china 3 school of Science,beijing university of Posts and Telecommunications,beijing 100876,china 4 Institute of Electronic Technology,Information Engineering university,Zhengzhou 450004,china 5 Trusted Computing laboratory,beijing university of Technology,beijing 100022,china College of Computer Science Technology Beijing University of Technology Beijing 100022 China state key laboratory of Information Security [Graduate university of the Chinese Academy of sciences] Beijing 100049 China school of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing laboratory Beijing University of Technology Beijing 100022 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

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Second mode unstable disturbance measurement of hypersonic boundary layer on cone by wavelet transform

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Acta Mechanica Sinica 2011年第4期27卷 488-493页

作者： Jian Han.Nan Jiang.Yan Tian Department of Mathematics,Tianjin university,300072 Tianjin,china Department of Mechanics,Tianjin university,300072 Tianjin,china Tianjin key laboratory of Modern Engineering Mechanics,300072 Tianjin,china state key laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of sciences,100190 beijing,china Department of Mathematics Tianjin University Tianjin China Department of Mechanics Tianjin University Tianjin China Tianjin key laboratory of Modern Engineering Mechanics Tianjin China state key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

Experimental investigation of hypersonic boundary layer instability on a cone is performed at Mach number 6 in a hypersonic wind tunnel. Time series signals of instantaneous fluctuating surface-thermal-flux are measured by Pt-thin-film thermocouple temperature sensors mounted at 28 stations on the cone surface in the streamwise direction to investigate the development of the unstable disturbance. Wavelet transform is employed as a mathematical tool to obtain the multi-scale characteristics of fluctuating surfacethermal-flux both in the temporal and spectrum space. The conditional sampling algorithm using wavelet coefficient as an index is put forward to extract the unstable disturbance waveform from the fluctuating surface-thermal-flux *** generic waveform for the second mode unstable disturbance is obtained by a phase-averaging technique. The development of the unstable disturbance in the streamwise direction is assessed both in the temporal and spectrum space. Our study shows that the local unstable disturbance detection method based on wavelet transformation offers an alternative powerful tool in studying the hypersonic unstable mode of laminar-turbulent transition. It is demonstrated that, at hypersonic speeds, the dominant flow instability is the second mode, which governs the course of laminar-turbulent transition of sharp cone boundary layer.

关键词： Hypersonic boundary layer. Sharp cone Insta-bility Wavelet transform

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A new transient stability margin based on dynamic security region and its applications

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Science china(Technological sciences) 2008年第6期51卷 751-760页

作者： XUE AnCheng1, 2 & MEI ShengWei1 1 state key Lab of Power Systems, Department of Electrical Engineering, Tsinghua university, beijing 100084, china 2 key Lab of Systems and Control, Institute of Systems Science, Chinese Academy of sciences, beijing 100190, china 1. state key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China 2. key Lab of Systems and Control Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

A new transient stability margin is proposed based on a new expression of dynamic security region (DSR) which is developed from the existing expression of DSR. Applications of the DSR based transient stability margin to contingency ranking and screening are discussed. Simulations in the 10-machine 39-bus New England system are performed to show the effectiveness of the proposed DSR based tran-sient stability margin.

关键词： dynamic security region (DSR) transient stability margin contingency screening

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Two new species of Vestrogothia (Phosphatocopina, Crustacea) of Orsten-type preservation from the Upper Cambrian in western Hunan, South china

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Science china Earth sciences 2009年第6期52卷 784-796页

作者： ZHANG HuaQiao1,2 & DONG XiPing1,2 1 school of Earth and Space sciences,Peking university,beijing 100871,china 2 state key laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,china school of Earth and Space sciences Peking University Beijing 100871 China state key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Although fossils of Orsten-type preservation represented by Skaracarida and Phosphatocopina were first reported from the Middle and Upper Cambrian in western Hunan, South china in 2005, diversified phosphatocopine species have never been appropriately described and elucidated in terms of their evolutionary relationships. Here, we described two new species of Phosphatocopina, Vestrogothia anterispinata sp. nov. and V. bispinata sp. nov. The evolutionary relationship among all the valid species of Phosphatocopina is discussed and the phylogeny of Phosphatocopina is reestablished using cladistic analysis. Accordingly, phosphatocopines primitively evolved along two lineages: one evolved towards the emergence of lobes; the other evolved towards the emergence of dorsal spines. Respectively, lobes originated independently three times, and dorsal spines originated only once. With regard to the dorsal rims, interdorsum originated first, whereas dorsal furrow originated independently twice on the basis of interdorsum. Probably Hesslandona may represent a polyphyletic group, whereas Vestrogothia a monophyletic group.

关键词： fossils of Orsten-type preservation Vestrogothia Phosphatocopina Crustacea evolution phylogeny Cambrian Hunan

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Study on simulation and experiment of array micro Faraday cup ion detector for FAIMS

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Science china(Technological sciences) 2010年第12期53卷 3225-3231页

作者： TANG Fei, WANG XiaoHao, ZHANG Liang & YAN ZiLin state key laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments and Mechanology, Tsinghua university, beijing 100084, china 1. state key laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

An array micro Faraday cup ion detector for FAIMS (High-field Asymmetric Waveform Ion Mobility Spectrometry) was introduced, with which the size of the FAIMS system was reduced. With simple structure, good stability, low noise, large measurements range, this detector can work under the condition of atmospheric pressure. The array micro Faraday cup was composed of gate electrode, sensitive electrode and shielding electrode. The sensitive electrode was made of tens of crossing silicon columns with diameter of 200 μm. It was fabricated through typical MEMS technology, which was compatible completely with plane FAIMS. It was shown from FLUENT simulation result that the resistance to gas motion was low and the flow field distribution was helpful for full absorption of the ion in this array design. Through electricity simulation, the method to reduce interference on the detection signal of the micro Faraday cup was given out. Connecting with KEITHLEY 237 ampere meter, the noise level of the array micro Faraday cup was lower than 0.5 pA. The output signal of the acetone sample measured by experiment was about 210 pA. Through contrast experiment, the design parameter of the micro Faraday cup was obtained primarily. This array micro Faraday cup can meet the requirements of the FAIMS system.

关键词： FAIMS MEMS Faraday cup ion detector low current

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Solving the constrained shortest path problem using random search strategy

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Science china(Technological sciences) 2010年第12期53卷 3258-3263页

作者： LI KePing, GAO ZiYou , TANG Tao & YANG LiXing state key laboratory of Rail Traffic Control and Safety, beijing Jiaotong university, beijing 100044, china 1. state key laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China

In this paper, we propose an improved walk search strategy to solve the constrained shortest path problem. The proposed search strategy is a local search algorithm which explores a network by walker navigating through the network. In order to analyze and evaluate the proposed search strategy, we present the results of three computational studies in which the proposed search algorithm is tested. Moreover, we compare the proposed algorithm with the ant colony algorithm and k shortest paths algorithm. The analysis and comparison results demonstrate that the proposed algorithm is an effective tool for solving the constrained shortest path problem. It can not only be used to solve the optimization problem on a larger network, but also is superior to the ant colony algorithm in terms of the solution time and optimal paths.

关键词： constrained shortest path deterministic random walk optimization

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Preparation and Characterization of Palladium Colloidal Nanoparticles by Thermal Decomposition of Palladium Acetate with Microwave Irradiation

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Journal of Materials Science & Technology 2005年第2期21卷 187-190页

作者： Yixian CHEN, Baolin HE and Hanfan LIU Hubei key laboratory for Catalysis and Material Science, university of South-Central for Nationalities, Wuhan 430074, china PCLCC, state key laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of sciences, beijing 100080, china Lab. for Catalysis and Mat. Sci. Univ. of South-Central for Natl. Wuhan 430074 China Lab. of Polymer Phys. and Chem. Inst. of Chem. Chinese Acad. of Sci. Beijing 100080 China

A series of solvent-stabilized palladium colloidal nanoparticles were prepared via thermal decomposition of palladium acetate methylisobutylketone (MIBK) solution in the presence of alkali and alcohol with microwave irradiation. The colloidal nanoparticles were characterized with TEM, XPS and XRD. The average diameters of nanoparticles increase from 30 to 40 nm with the increase in concentration of palladium acetate. TEM and XRD observation demonstrated that the palladium colloidal nanoparticles were clusters agglomerated from hundreds of smaller palladium crystallines with size of 3-4 nm. The influence of the concentrations of alkali and alcohol to the particle size was also discussed.

关键词： Thermal decomposition Microwave Palladium acetate Methylisobutylketone

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A multiphase mesostructure mechanics approach to the study of the fracture-damage behavior of concrete

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Science china(Technological sciences) 2008年第S2期51卷 8-24页

作者： TANG XinWei1,ZHANG ChuHan1 & SHI JianJun2 1 state key laboratory of Hydroscience and Engineering,Tsinghua university,beijing 100084,china 2 Department of Urban Construction,Nanhua university,Hengyang 421001,china 1. state key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China 2. Department of Urban Construction Nanhua University Hengyang 421001 China

A multiphase mesostructure mechanical model is proposed to study the deformation and failure process of concrete considering its heterogeneity at the meso scopic ***,concrete is taken as a type of three-component composite material composed of mortar matrix,aggregates and interfaces on the ***,an efficient approach to the disposition of aggregates of concrete and a state matrix method to generate mesh coordinates for aggregates are ***,based on the nonlinear continuum damage mechanics,a meso-scale finite element model is presented with damage softening stress-strain relationship for describing the mechanical behavior of different components of *** this method,heterogeneities of each component in the concrete are considered by assuming the material properties of three components conform to the Weibull distribution ***,based on this multiphase meso-mechanics model,a simulation analysis of fracture behavior of a rock-fill concrete(RFC) beam is *** study includes experimental tests for determining basic mechanical parameters of three components of RFC and four-point flexural beam tests for verification of the *** is preliminarily shown that the numerical model is applicable to studying failure mechanisms and process of concrete type material.

关键词： concrete multiphase mesostructure mechanics numerical simulation experimental research

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New method for computing unstable equilibrium points of power systems with induction motors

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Science china(Technological sciences) 2010年第4期53卷 881-885页

作者： CHEN Lei,XU Fei & MIN Yong state key Lab of Power Systems,Department of Electrical Engineering,Tsinghua university,beijing 100084,china 1. state key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

The computation of the unstable equilibrium point(UEP) is a key step involved in stability region estimation of nonlinear dynamic systems.A new continuation-based method to compute the UEPs of a power system with induction motors is *** mechanical torques of motors are changed to form a parameterized equation *** the solution curve of the equation set is traced by the continuation method from the stable equilibrium point to a *** direction of mechanical torque change is varied to get multiple *** obtained UEPs are mostly *** fast assessment of induction motor stability is studied by approximating the stable manifolds of the *** method is tested in several systems and satisfactory results are obtained.

关键词： power system stability transient voltage stability unstable equilibrium point(UEP) stability boundary induction motor

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CMQV+:An authenticated key exchange protocol from CMQV

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Science china(Information sciences) 2012年第7期55卷 1666-1674页

作者： LI Hui 1,2 & WU ChuanKun 1 1 state key laboratory of Information Security,Institute of Software,Chinese Academy of sciences,beijing 100190,china 2 Graduate university of Chinese Academy of sciences,beijing 100049,china 1. state key laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Ustaoglu presents a secure and efficient key exchange protocol named CMQV,based on the design rationales of HMQV and *** with the latter two protocols,on one hand,CMQV achieves high performance of HMQV,and on the other,it is proven secure in eCK model as NAXOS ***,CMQV enjoys the security proof under gap Diffie-Hellman assumption as indicated by its *** this paper,we propose a variant of CMQV,called CMQV+,which is proven secure under a weaker assumption (*** Diffie-Hellman assumption) in eCK model with random oracles while maintaining the high-performance feature of CMQV as much as possible.

关键词： key exchange eCK model trapdoor-test technique provable security CDH assumption

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