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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 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

Use-wear analysis confirms the use of Palaeolithic bone tools by the Lingjing Xuchang early human

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Chinese Science Bulletin 2010年第21期55卷 2282-2289页

作者： LI ZhanYang 1,4 & SHEN Chen 2,3,4 1 Henan Provincial Institute of Cultural Relics and Archaeology,Zhengzhou 450000,china 2 The Joint Laboratory of Human Evolution and Archaeometry,Chinese Academy of Sciences,beijing 100044,china 3 The Royal Ontario Museum,Toronto ON M5S2C6,Canada 4 Oriental Archaeology research Center of Shandong University,Jinan 250100,china Henan Provincial Institute of Cultural Relics and Archaeology Zhengzhou 450000 China Oriental Archaeology research Center of Shandong University Jinan 250100 China The Joint Laboratory of Human Evolution and Archaeometry Chinese Academy of Sciences Beijing 100044 China The Royal Ontario Museum Toronto ON M5S2C6 Canada

During 2007-2008 excavations at the Lingjing site near Xuchang,Henan Province,dated back to around 100-80 ka ago,a large quantity of mammalian fossil remains were recovered along with a remarkable cluster of Early Modern Human(EMH) skull fragments in *** some of those animal bones were probably modified into tools.A use-wear analysis was carried out to examine the functions of modified bone *** results suggest that Lingjing bone tools were used for drilling,penetrating,and scraping animal substances,and that some might have been hafted during the *** study confirms that early existence ofintentionally-modified bone tools at human occupations of the early Late Pleistocene in northern *** discovery suggests making and use of bone tools were inevitably a part of early human behaviors and cultural development,as such of stone tools.

关键词：早期人类磨损分析旧石器时代工具许昌哺乳动物化石现代人类动物骨头

A Discussion on Evolution of Microstructures and Influence Factors during Continuous Rolling of Compact Strip Production

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Journal of Materials Science & Technology 2004年第3期20卷 274-278页

作者： Hongbo DONG Yonglin KANG Hao YU Department of Materials Processing and Controlling, University of Science and Technology beijing, beijing 100083. china Dept. of Mat. Proc. and Control Univ. of Sci. and Technol. Beijing Beijing 100083 China

The evolution of microstructures and influence factors of ultrathin hot strips of low carbon steel produced by compactstrip production (CSP) techniques were investigated. The steel blocking samples of CSP six-passes were obtained,and microstructures at the different positions of workpiece for each pass were studied. At the same time, anexplicit finite element technique was used to reveal the continuous rolling process. By combining experiment resultswith simulation analysis, the effects of plastic strain, temperature, precipitation and interval time on evolution andrefinement of crystal grains have been investigated. The results are useful for the development of high strength hotstrips.

关键词： CSP Microstructure Strain Temperature Precipitation

Micro-mechanisms of residual oil mobilization by viscoelastic fluids

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Petroleum Science 2008年第1期5卷 56-61页

作者： Zhang Lijuan Yue Xiang＇an Guo Fenqiao Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China development Department Sinopec Exploration and Production Research Institute Beijing 100083 China

Four typical types of residual oil, residual oil trapped in dead ends, oil ganglia in pore throats, oil at pore corners and oil film adhered to pore walls, were studied. According to main pore structure characteristics and the fundamental morphological features of residual oil, four displacement models for residual oil were proposed, in which pore-scale flow behavior of viscoelastic fluid was analyzed by a numerical method and micro-mechanisms for mobilization of residual oil were discussed. Calculated results indicate that the viscoelastic effect enhances micro displacement efficiency and increases swept volume. For residual oil trapped in dead ends, the flow field of viscoelastic fluid is developed in dead ends more deeply, resulting in more contact with oil by the displacing fluid, and consequently increasing swept volume. In addition, intense viscoelastic vortex has great stress, under which residual oil becomes small oil ganglia, and finally be carried into main channels. For residual oil at pore throats, its displacement mechanisms are similar to the oil trapped in dead ends. Vortices are developed in the depths of the throats and oil ganglia become smaller. Besides, viscoelastic fluid causes higher pressure drop on oil ganglia, as a driving force, which can overcome capillary force, consequently, flow direction can be changed and the displacing fluid enter smaller throats. For oil at pore corners, viscoelastic fluid can enhance displacement efficiency as a result of greater velocity and stress near the corners. For residual oil adhered to pore wall, viscoelastic fluid can provide a greater displacing force on the interface between viscoelastic fluid and oil, thus, making it easier to exceed the minimum interfacial tension for mobilizing the oil film.

关键词： Viscoelastic chemical flooding displacement mechanism residual oil swept volume

research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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Science china(Technological Sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2 &CHEN QiuWen 3 1 Ertan Hydropower development Company,Ltd.,Chengdu 610051,china 2 china Institute of Water Resources and Hydropower research,beijing 100038,china 3 research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,beijing 100085,china 1. Ertan Hydropower development Company Ltd. Chengdu 610051 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China3. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 305 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (Department of Bioengineering, School of Chemical and Environmental Engineering, china University of Mining and Technology (beijing), beijing 100083. china Department of Biology, Graduate University of Chinese Academy of Sciences, beijing 100049, china) [a]Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beiing) Beijing China [b]Department of Biology Graduate University of Chinese Academy of Sciences Beijing China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

Final Temperature Prediction Model of Molten Steel in RH-TOP Refining Process for IF Steel Production

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Journal of Iron and Steel research International 2012年第3期19卷 1-5页

作者： WANG Yu-nan1, BAO Yan-ping1, CUI Heng2, CHEN Bin3, JI Chen-xi3 (1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology beijing, beijing 100083. china 2. Engineering research Institute, University of Science and Technology beijing, beijing 100083. china 3. Shougang research Institute of Technology, beijing 100041, china) [a] State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China [b] Engineering research Institute University of Science and Technology Beijing Beijing 100083 China [c] Shougang research Institute of Technology Beijing 100041 China

In order to precisely control the final temperature of molten steel in RH （Ruhrstahl Heraeus）-TOP blowing refining, the final temperature prediction models of molten steel in RH-TOP blowing refining process for Interstitial Free （IF） steel production were established under the condition of oxygen blowing and non-oxygen blowing respec- tively. The results show that the beginning molten steel temperature of refining and the amount of added scrap were influential factors, the baking temperature in vacuum chamber was a factor that had small influence. When the model was operated, the hitting probability was above 95%（under the condition of both oxygen blowing and non-oxygen blo- wing） of prediction deviation ±10℃. The accuracy is analyzed.

关键词： RH-TOP molten steel temperature prediction model

Identification of marine natural gases with different origin sources

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Science china Earth Sciences 2008年第S1期51卷 148-164页

作者： WANG YunPeng 1 ,ZHAO ChangYi 2 ,WANG ZhaoYun 2 ,WANG HongJun 2 ,TIAN Jin 1 ,ZOU YanRong 1 &LIU JinZhong1 1State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,china 2Institute of Geology,research Institute of Petroleum Exploration and development,Petrochina,beijing 100083.china State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Institute of Geology Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083

Kinetic experiments of gas generation for typical samples of marine gas precursors including low-maturity kerogen,residual kerogen and oil as well as dispersed liquid hydrocarbon(DLH)in source rocks were performed by closed system,and the evolution trends of molecular and isotopic compositions of natural gases from different precursors against the maturity(R0%)at laboratory conditions were *** diagrams of gas origin were calibrated by using the experimental data.A diagram based on the ratio of normal and isomerous butane and pentane(i/nC4-i/nC5)was proposed and used to identify the origins of the typical marine natural gases in the Sichuan Basin and the Tarim Basin, *** the maturities of natural gases were estimated by using the statistical relationships between the gaseous molecular carbon isotopic data and maturities(δ13.-R 0 %)with different *** results indicate that the molecular and isotopic compositions of simulated gases from different precursors are different from each *** example,the dryness index of the oil-cracking gas is the lowest;the dryness indices of gases from DLH and kerogen in closed system are almost the same;and the dryness index of gases from residual kerogen is extremely high,indicating that the kerogen gases are very dry;the contents of non-hydrocarbon gases in kerogen-cracking gases are far higher than those in oil-cracking and DLH-cracking *** molecular carbon isotopes of oil-cracking gases are the lightest,those of kerogen in closed system and GLH-cracking gases are the second lightest,and those of cracking gases from residual kerogen are the *** calibration results indicate that the diagrams of ln(C1/C2)-ln(C2/C3)andδ13.2-δ13.3-ln(C2/C3)can discriminate primary and secondary cracking gases,but cannot be used to identify gas origin sources,while the diagram of i/nC4-i/nC5 can differentiate the gases from different *** application results of these diagrams show that gas mixtures ext

关键词： marine organic matter gas origin sources kerogen oil-cracking gas origin identification carbon isotope

Metallogenic epoch and genesis of the gold deposits in Jiaodong Peninsula, Eastern china: a regional review

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Progress in Natural Science:Materials International 2007年第2期17卷 138-143页

作者： YANG Liqiang, DENG Jun, GE Liangsheng, WANG Qingfei, ZHANG Jing, GAO Bangfei, JIANG Shaoqing and XU Hao ( State Key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, beijing 100083. china Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china University of Geosciences, beijing 100083. china) [a]State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China [b]Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China

Gold deposits are characterized by multi-sources, superimposition, large scale and temporal-spatial concentration in Jiaodong Peninsula, Eastern china. In this paper, we review the history and the development of the study on metallogenic chronology and genesis of gold deposits, summarize the main features of superimposed metallogenesis, provide evidence of the Mesozoic complex metallogenic system, and point out some problems for further research of Jiaodong gold deposit cluster from a regional view. Although gold deposits are different in genetic types, ore-forming materials and geological settings, our research indicates that the accumulation and emplacement of the ore-forming materials are temporally-spatially concentrated on a large scale, and the main metallogenic epoch of Jiaodong gold deposits was concentrated in Mesozoic. Metallogenic chronology and geological-geochemical data indicate that there are two periods of gold mineralizations occurred in 13.-110 Ma and 90-80 Ma respectively in Jiaodong ore cluster. The gold deposit cluster results from the superimposition of the polygenetic mineralization, and further study is needed to investigate the formation and evolution of the Mesozoic complex metallogenic system.

关键词： superimposed metallogenic system Mesozoic Jiaodong ore cluster.