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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,beijing university of Technology,beijing 100022,China 2 State Key Laboratory of {3. 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,{3. 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

The Process of TiB_2-Cu Composite Phase and Structure Formation during Combustion Synthesis

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 113-116页

作者：徐强 school of Materials Science and engineering Beijing Insitute of TechnologyBeijing 100081China

The reaction process of combustion synthesis for TiB2 -Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction （ XRD ） analysis, SEM analysis and differential thermal analysis （ DTA ）. The XRD analysis results for the different parts of the quenched specimen show that TiCux intermetallic phase firstly forms with the propagation of combustion wave, and then Ti1.87 B50 and Ti3.4 metastable phases come forth due to the diffusion of B atoms and finally the stable TiB2 phase forms because of the continuous diffusion of B atoms. The formation of TiB2 phase is uot completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti-B-Cu ternary system can be divided into three main stages： melting of Cu and Ti , and the formation of Cu- Ti melt and few TiCux , TiBx intermetallic phases ; large numbers of TiCux intermetallic phases formation and some fine TiB2 particles precipitation ; and the TiB2 particles coarsening and the stable TiB2 and Cu two phases formation in the final product.

关键词： combustion synthesis reaction process TiB2 phase combustion-wave arresting experiment

An efficient quantum secret sharing protocol with orthogonal product states

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Science China(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3.& ZHU FuChen4 1 school of Computer, beijing university of Technology, beijing 100022, China 2 State Key Laboratory of information Security, Graduate university of Chinese Academy of Sciences, beijing 100022, China 3.school of Science, beijing university of Posts and Telecommunications, beijing 100876, China 4 National Key Laboratory for Modern Communications, Chengdu 610041, China 1. school of Computer Beijing University of Technology Beijing 100022 China 2. State Key Laboratory of information Security Graduate University of Chinese Academy of Sciences Beijing 100022 China 3. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China 4. National Key Laboratory for Modern Communications Chengdu 610041 China

An efficient quantum secret sharing protocol with orthogonal product states in the 3.3.Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Optimization of Fractal Iterated Function System(IFS) with Probability and Fractal Image Generation

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Journal of university of Science and Technology beijing 2001年第2期8卷 152-156页

作者： Berthe Kya, Yang Yang (information engineering school, {3. of Science and Technology beijing, beijing 100083. China) Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

There are several methods for rendering fractal images based on IFS (Iterated Function System) in computer graphic; but one concern of the computer graphic community has been the efficiency rendering algorithms. The invariant measures arising from IFSP (Iterate Function System with Probability) using the probabilistic algorithm are also known as chaos games. The role of these probabilities to generate the image of the attractor has been investigated using a multi-fractal analysis. The conventional choice of probability associated with each set /S/ to generate the attractor in least time possible is introduced, then a new method based on the self similarity and multi-fractal analysis is presented. The efficiency of the new method has been proved over the conventional method.

关键词： optimization of fractal IFS compression IFSP multi-fractal analysis

Secure network coding in the presence of eavesdroppers

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Science China(information Sciences) 2010年第3期53卷 648-658页

作者： LUO MingXing1,2,3. YANG YiXian1,2,3. WANG LiCheng1,2,3.& NIU XinXin1,2,3.1information Security Center, State Key Laboratory of Networking and Switching Technology, beijing university of Posts and Telecommunications, beijing 100876, China 2Key Laboratory of Network and information Attack and Defence Technology of MOE, beijing university of Posts and Telecommunications, beijing 100876, China 3.ational engineering Laboratory for Disaster Backup and Recovery, beijing university of Posts and Telecommunications, beijing 100876, China 1. information Security Center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Network and Information Attack and Defence Technology of MOE Beijing University of Posts and Telecommunications Beijing 100876 China3. National Engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and Telecommunications Beijing 100876 China

Our concern, in the paper, is to construct information-theoretic secure network coding in the presence of eavesdroppers. Based on the generalized attack model and all-or-nothing transformation, the security of network coding in the generalized combination network can be characterized by the network capacity and the min-cut bound of wiretapping set from the source. Furthermore, it can be extended to any directed acyclic networks with single source. Compared with the traditional results, we construct information-theoretic secure network coding without additional encryptions and giving up any capacity.

关键词： all-or-nothing transformation secure network coding eavesdropping

The precipitation and effect of nano nitrides in HSLC steel

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Science China(Technological Sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2 & WU HuaJie1,3.1 school of Metallurgical and Ecological engineering, university of Science and Technology {3., {3. 100083. China 2 Shougang Technology Research Institute, Shougang (Group) Corporation, {3. 100041, China 3.Metallurgical engineering Research Institute, university of Science and Technology {3., {3. 100083. China 1. school of Metallurgical and Ecological engineering University of Science and Technology Beijing Beijing 100083 China 2. Shougang Technology Research Institute Shougang (Group) Corporation Beijing 100041 China 3. Metallurgical engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043.. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel AlN nano nitride precipitation strengthening

Preparation of Pt/K_2La_2Ti_3._(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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Science China Chemistry 2006年第2期49卷 162-168页

作者： CUI Wenquan1,3. LIU Li2, FENG Liangrong1, XU Chenghua1, LI Zijian1, Lü Shaojie1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China 2. Chemistry Department, Sichuan university of Science & engineering, Zigong 643.3., China 3. Graduate school of the Chinese Academy of Sciences, {3. 10003., China Correspondence should be addressed to Qiu Fali 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China 3. Graduate school of the Chinese Academy of Sciences Beijing 100039 China 2. Chemistry Department Sichuan University of Science & Engineering Zigong 643033 China

A layered perovskite-type oxide K2La2Ti3.10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2La2Ti3.10 as a co-catalyst with different methods. The dispersion of platinum on K2La2Ti3.10 was determined with HOT method. The photocatalytic activity of Pt/K2La2Ti3.10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2La2Ti3.10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 23..88 μmol·h?1 by Pt(2%)/K2La2Ti3.10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2La_2Ti_3._(10) support

The band structures of BSb and B_xGa_(1-x)Sb alloys

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Science China(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2, WANG Qi3. LUO Li1, HUANG YongQing3.& REN XiaoMin3.1 school of Physics and Optoelectronic engineering, Guangdong university of Technology, Guangzhou 510006, China 2 College of {3. engineering, Zhejiang university of Technology, Hangzhou 3.003., China 3.Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education, beijing university of Posts and Telecommunications, beijing 100876, China 1. school of Physics and Optoelectronic engineering Guangdong University of Technology Guangzhou 510006 China 2. College of information engineering Zhejiang University of Technology Hangzhou 310032 China 3. Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

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Science China(Life Sciences) 2006年第2期49卷 115-122页

作者： ZHAO Hongxin1,2,3. XIE Baoen2 & CHEN Sanfeng1,2 1. State Key Laboratory for Agrobiotechnology and Biological school, China Agricultural university, beijing 100094, China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, China Agricultural university, beijing 100094, China 3. Chemical and Biological school, ShenYang Normal university, Shenyang 11003., China 1. State Key Laboratory for Agrobiotechnology and Biological school China Agricultural University Beijing 100094 China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry China Agricultural University Beijing 100094 China 3. Chemical and Biological school ShenYang Normal University Shenyang 110034 China

A 3.4 bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG; then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 10254 bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54]-dependent promoter sequence was detected upstream of the nifB gene; nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4 [+]; O2 showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.