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Research on applying physical chaos generator to spacecraft information security

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Science china(Technological Sciences) 2009年第5期52卷 1463-1470页

作者： ZHAO HePing State Key Laboratory of Information Security,graduate university of Chinese Academy of Sciences,beijing 100049,china china Academy of Space Technology,beijing 100094,china State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China china Academy of Space Technology Beijing 100094 China

The effectiveness of a short-length message extension method based on physical chaos generator was analyzed and the entropy of the extended message was calculated in this *** analysis demon-strated that with the mentioned method the entropy of short-length messages,which are repeatedly used in spacecraft data systems,is obviously increased,and the security of transmission is enhanced as *** paper also presented an improvement of the protocol for secret key agreement presented by *** and *** of depending on characteristics of communication channel,this method takes advantage of the random data produced by physical chaos generator to preset the initial parameters of the procedure on both sides of communication,so that the procedure and quantity of cipher key can be precisely *** method can be used to cipher key management of se-cure communication between long life-span spacecraft and ground system.

关键词： physical chaos generator spacecraft information security message extension cipher key management

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

Linear EV model with replicate observations on independent variables

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Science china Mathematics 2006年第6期49卷 752-769页

作者： LIU Jixue, ZHANG Sanguo & CHEN Xiru Department of Statistics and Finance, university of Science and Technology of china, Hefei 230026, china Department of Mathematics, graduate school of Chinese Academy of Sciences, beijing 100049, china 1. Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China 2. Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing 100049 China

This paper studies the linear EV model when replicate observations are made only on independent variables. We construct the estimates of regression coefficients and prove the consistency and asymptotic normality under some proper conditions. Results obtained reveal the difference between the case where the independent and dependent variables are observed repeatedly and simultaneously and the case studied in this article.

关键词： linear EV model, consistency, asymptotic normality.

The Global Existence of One Type of Nonlinear Kirchhoff String Equation

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 477-484页

作者： Xiao-yi Zhangbeijing graduate school of china Academy of Engineering Physics, beijing 100088, china beijing graduate school of china Academy of Engineering Physics Beijing 100088 China

In this paper, the global well-posedness of initial-boundary value problem to the nonlinear Kirchhoff equation with source and damping term is established by energy method.

关键词： Kirchhoff equation global well-posedness

Indian Ocean-MORB-type isotopic signature of Yushigou ophiolite in North Qilian Mountains and its implications

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Science china Earth Sciences 2006年第6期49卷 561-572页

作者： HOU Qingye1,2, ZHAO Zhidan1,2, ZHANG Hongfei3, ZHANG Benren3 & CHEN Yuelong2 1. State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences, beijing 1.0083, china 2. school of Earth Science and Mineral Resources, china university of geosciences, beijing 1.0083, china 3. Faculty of Earth Sciences, china university of geosciences, Wuhan 430074, china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. school of Earth Science and Mineral Resources China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

In order to explore the disputed issue concerning the tectonic affinity ofthe ancient ocean mantle of North Qilian Mountains (NQM), geochemical and Sr, Nd, Pb isotopiccompositions of pillow basalts of the Yushigou Ophiolite (YSGO) suite from NQM have been analyzedsystematically. The pillow basalts exhibit tholeiitic characteristics, with flatchondrite-normalized REE patterns ((La/Yb)_N = 0.98—1.27). They display no Nb, Ta, Zr, Hf negativeanomalies, and show MORB features in 2Nb-Zr/4-Y and Ti/100-Zr-YX3 tectonic discrimination *** results indicate that the Yushigou ophiolite is most likely to be formed in a mid-ocean ridgeor mature back-arc basin. Their isotopic data show a relatively broad and enriched ^(87)Sr/^(86)Sr(0.70509 — 0.70700), restricted ^(143)Nd/^(144)Nd (0.512955-0.512978). Pb isotopes are in the rangeof ^(206)Pb/^(204)Pb (18.054-20.562), ^(207)Pb/^(204)Pb (15.537-15.743) and ^(208)Pb/^(204)Pb(38.068-38.530). These isotopic data imply that the basalts originated from the depleted mantle(DMM), with the involvement of enriched mantle components (mainly EMII). Geochemical comparisonsbetween the basalts in YSGO and the MORB-type basalts of ophiolite suites occurring in the knownancient Tethyan tectonic domain indicate that the ancient oceanic mantle represented by YSGO suiteforming in early Paleozoic in the North Qilian Moutains is very similar to the Tethyan mantle inboth trace elements and isotopic compositions. The North Qilian Mountains should be a part of theTethyan tectonic domain in early Paleozoic. This further implies that the Tethyan tectonic domaincan be deduced to early Paleozoic in the study area, which will be helpful to discussing thetectonic affinity and evolution of the North Qilian Mountains.

关键词： geochemistry, Indian Ocean-MORB-type isotopic signatures, Tethyan tectonic domain, Yushigou ophiolite, North Qilian Mountains.

Prediction of Enthalpies of Fusion for Divalent Rare Earth Halides Based on Modeling by Artificial Neural Networks and Pattern Recognition

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 24-26页

作者： Yimin Sun Zhiyu Qiao Minghong He(Applied Science school, university of Science & Technology beijing, beijing 1.0083, china)(National Natural Science Foundation of china, beijing 1.0083, china) Applied Science school University of Science and Technology Beijing Beijing 100083 China National Natural Science Foundation of china Beijing 100083 China

The artificial neural network (ANN) and the pattern recognition were applied to study the correlation of enthalpies of fusion for divalent rare earth halides with their microstructural parameters,such as ionic radius and electronegativity. The model,represented by a back-propagation netal network, was trained with a 12 set of published data for divalent rare earth halides and then was used to predict the unknown ones. Also the criterion equations were ptesented to determine the enthalpies of fuSion for divalent rare earth halides using pattern recognition in mis work. The results from the model in ANN and criterion equations are in very good agreement with reference data.

关键词： BP neural network pattern recognition enthalpy of fusion divalent rare earth halides microstructural parameters

Oxidation of O'-SiAlON-ZrO_2 Composite Ceramics

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Journal of university of Science and Technology beijing 2001年第1期8卷 43-47页

作者： Xidong Wang , Hong Bao, Wenchao Li Metallurgy school, university of Science and Technology beijing, beijing 1.0083, china Department of Metallurgy, East china university of Metallurgy Maan Shan 243002, china Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China E china Univ Met Dept Met Maan Shan 243002 Peoples R China

The oxidation kinetics of O'-SiAlON-ZrO2 composite ceramics in the temperature range of 1373-1773K has been studied. The oxidation experiments with powder and plates of O'-SiAlON-ZrO2 composite ceramics in air have been carried out. The overall activation energy of oxidation reaction is 263.69 kJ/mol. The products and structures of O'-SiAlON-ZrO2 oxidation layer have been analysed by XRD (X-ray diffraction), SEM (scanning electron microscope) and AFM (atomic force microscope).

关键词： O '-SiAlON ZrO2 ceramics oxidation

NEW ROBUST UNSUPERVISED SUPPORT VECTOR MACHINES

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Journal of Systems Science & Complexity 2011年第3期24卷 466-476页

作者： Kun ZHAO Mingyu ZHANG ~ Naiyang DENG Logistics school Beijing Wuzi University Beijing 101149 China. school of Economic and Management Beijing Jiaotong University Beijing 100044 China. College of Science China Agricultural University Bcijing 100083 China.

This paper proposes robust version to unsupervised classification algorithm based on modified robust version of primal problem of standard SVMs, which directly relaxes it with label variables to a semi-definite progra... 详细信息

关键词： Robust semi-definite programming support vector machines unsupervised learning

Pioneer organisms after F-F mass extinction in Dushan region,Guizhou Province,and their significance in establishing new ecosystem

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Science china Earth Sciences 2006年第5期49卷 449-460页

作者： WANG Yue1, 2, WANG Xunlian1 & SHI Xiaoying1 1. school of Earth Sciences and Resources, china university of geosciences, beijing 1.0083, china 2. school of Resources and Environment, Guizhou university, Guiyang 550003, china 1. school of Earth Sciences and Resources China University of Geosciences Beijing 100083 China 2. school of Resources and Environment Guizhou University Guiyang 550003 China

After mass extinctions, most areas became “ecologically barren areas” lacking or even without ecosystem over an extensive region. Studying the pioneer organisms and the reconstruction process of a new ecosystem in the “ecologically barren area” is very important for revealing the evo- lution after bio-mass extinctions. In the Dushan region, Guizhou Province, china, the trace fossils appeared and flourished evidently earlier than body fossils after Frasnian-Famennian (F-F) mass extinction. The pioneer organisms and pathfinders in the “ecologically barren areas” are the trace-makers that are deposit-feeders with relatively simple structure and conformation on or near the deposit surface. The trace-makers have undergone an evolutionary process that their trace structures changed from simple to complex, and their living and moving areas and spaces enlarged from linear to planar and then to three-dimension spaces. Those characters show that the ability of the trace-makers to deposits and their efficiency of looking for food have been enhanced gradually and that those trace-makers constructed gradually a base for the new ecosystem. This process is similar to that of the trace fossils near the Precambrian-Cambrian boundary. In the Dushan area, only the recovery intervals have been identified for the Famennian body fossils, with no eminent radiation interval recognizable due to the Devonian-Carboniferous (C-D) mass ex- tinction. However, both the recovery and radiation intervals may be clearly recognized in the Famen- nian trace fossils based on their conformation and diversity. The evolution and diversification of the trace fossils in the “ecologically barren area” is considered to have played a role of necessary foun- dation for the recovery of body fossils in the ecological chain. With the gradual disappearance of the unfavourable environment factors resulting in the F-F mass extinction, a new ecosystem was reconstructed in the “ecologically barren area” through a three-

关键词： pioneer organisms, reconstruction of ecosystem, trace fossils, F-F mass extinction, Later Devonian, Dushan region, Guizhou Province, china.