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A NEW STABILIZED FINITE ELEMENT METHOD FOR SOLVING THE ADVECTION-DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2002年第1期20卷 57-64页

作者： Huo-yuan Duan (institute of Mathematics, academy of Mathematics and System sciences,{3., Beijing 100080, China) institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

Focuses on a study on the development of a stabilized finite element method for solving the advection-diffusion equations with a zero Dirichlet boundary condition. Problem formulation; Error analysis.

关键词： advection-diffusion equation stabilized finite element method

Floral organogenesis of Delavaya toxocarpa (Sapindaceae;Sapindales)

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Journal of Systematics and Evolution 2009年第3期47卷 237-244页

作者： 1,2,3.i-Min CAO 1Nian-He XIA 1(institute of Economic botany, south China Botanical Garden,{3., guangzhou 510650, China) 2(Department of Life sciences, Hengyang Normal University, Hengyang 421008, China) 3.Graduate University of{3., Beijing 100049, China) (Graduate University of chinese academy of sciences Beijing 100049 China)

The floral organogenesis and development of Delavaya toxocarpa Franch. (Sapindaceae) were studied under scanning electron microscope and light microscope to determine its systematic position within Sapindaceae. Flowers arise in terminal thyrses. The sepal primordia initiate in a spiral (2/5) sequence, which are not synchronous. The flve petal primordia initiate almost synchronously and alternate with sepal primordia. Eight stamens initiate almost simultaneously and their differentiation precedes that of the petals. The last formed petal and one stamen initiate from a common primordium. Mature stamens curve inwards and cover the ovary in bud. The gynoecium begins as a hemispheric primordium on which two carpellary lobes arise simultaneously. Later in development a single gynocium is formed with two locules and two ovules per locule. Floral morphology suggests a closer affinity with Sapindaceae, although certain features of floral ontogenesis are similar to those observed in certain members of the former Hippocastanaceae, such as Handeliodendron.

关键词： Delavaya toxocarpa Franch. floral organogenesis Hippocastanaceae Sapindaceae.

Leakproof secret sharing protocols with applications to group identification scheme

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Science China(Information sciences) 2012年第5期55卷 1172-1185页

作者： TANG ChunMing 1,2 & GAO ShuHong 3.1 School of Mathematics and Information Science,guangzhou University,guangzhou 510006,China 2 State Key Laboratory of Information Security,institute of Software Science,{3. academy of sciences,Beijing 100049,China 3.Department of Mathematical sciences,Clemson University,SC 2963.,USA 1. School of Mathematics and Information Science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100049 China3. Department of Mathematical Sciences Clemson University Clemson SC 29634 USA

In a traditional (t,n)-threshold secret sharing scheme,t or more honest participants can reconstruct the secret *** the reconstruction process,the individual shares and the secret key K are revealed,hence K is shared once *** this paper,we firstly give the definition of leakproof secret sharing scheme which is composed of a distribution protocol and a proof protocol,then propose two leakproof secret sharing protocols,a computationally secure protocol and an information-theoretically secure *** our protocols,t or more participants can jointly prove that they hold the secret K by using a multi-prover zero-knowledge argument of *** a result,the secret K will be shared for as many times as ***,each participant can detect the dealer in the distribution protocol from cheating,and any verifier can prevent non-qualified set of participants in proof protocol from *** an example of the practical impact of our work we use our techniques to construct group identification schemes with zero-knowledge.

关键词： secret sharing leakproof secret sharing multi-prover zero-knowledge argument proof of knowl-edge group identification scheme

Quantitative relationships between vegetation and several pollen taxa in surface soil from North China

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chinese Science Bulletin 2000年第16期45卷 1519-1523页

作者： LI Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and Environmental sciences, Peking University, Beijing 100871, China 2. Laboratory of Quantitative Vegetation Ecology, institute of botany,{3., Beijing 100093. China 3. School of Urban and Environmental sciences, Northeast Normal University, Changchun 13.024, China Correspondence should be addressed to Li Yiyin Department of Urbon and Environmental sciences Peking University Beijing China School of Urban and Environmental sciences Northeast Normal University Changchun China Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept

关键词： pollen taxa in surface soil vegetation regression parameters (slope term and y-intercept term) representation Northeast China Transect (NECT).

MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE-Ⅱ SUPERCONDUCTORS

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Journal of Computational Mathematics 1997年第4期15卷 365-384页

作者： Zhi-ming Chen (institute of Mathematics, chinese academy of sciences, Beijing, China) 中科院数学所北京

In this paper we seek the solutions of the time dependent Ginzburg-Landau model for type-Ⅱ superconductors such that the associated physical observables are spatially periodic with respect to some lattice whose basic lattice cell is not necessarily rectangular. After appropriately foring the gange, the model can be formulated as a system of nonlinear parabolic partial differential equations with quasi-periodic boundary conditions. We first give some results concerning the existence, uniqueness and regularity of solutions and then we propose a semiimplicit finite element scheme solving the system of nonlinear partial dmerential equations and show the optimal error estimates both in the L2 and energy *** also report on some numerical results at the end of the paper.

关键词： Math QT MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE SUPERCONDUCTORS

Urban effects and summer thunderstorms in a tropical cyclone affected situation over guangzhou city

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Science China Earth sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3.YAN JingHua1 & HU HaiBo2 1 institute of Tropical and Marine Meteorology,chinese Meteorological Administration(CMA),guangzhou 510080,China 2 institute of Urban Meteorology,CMA,Beijing 100089,China 3.State Key Laboratory of Severe Weather,chinese academy of Meteorological sciences,Beijing 100081,China 1. institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from guangzhou mesonet Automatic Weather Stations(AWS),guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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Science China Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3.& YE Xianren2 1. Resources and Environmental School, Lanzhou University, Lanzhou 73.000, China 2. Key Laboratory of Gas Geochemistry, institute of Geology and Geophysics, chinese academy of sciences, Lanzhou 73.000, China 3. College of Resources Science & Technology, Beijing Normal University, Beijing 100875, China 1. Resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of Resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3.e/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3.e from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Discovery of submicron diamonds within kimberlite in Liaoning Province, China and its significance

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chinese Science Bulletin 1997年第11期42卷 939-941页

作者： BAO Yanan, T. V. Dubuchick and T. D. Liabchekov1. Graduate School in Beijing, chinese Mining University, Beijing 100083. China 2. Moscow Resources institute of Mineral Materials, Russia 3. Resources institute of Deposit Geology, Russian {3. of sciences, Russia Graduate School in Beijing Chinese Mining University Beijing China Moscow Resources institute of Mineral Materials Russia Resources institute of Deposit Geology Russian Academy of Sciences Russia

ALTHOUGH a lot of research work on diamond mineralogy has already been done,the formationand development of diamond leave much to be *** have done some researches onthe diamond samples with obvious crystal-growing cha... 详细信息

关键词： submicron diamond lath-shape aggregative parent material.

Characteristics of phosphorus chemistry and its geographical distribution in the Haihe River valley,North China

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Journal of Environmental sciences 1995年第1期7卷 12-23页

作者： Jiang Gaoming Huang Yinxiao Lin Shunhua Han Rongzhuang Gao Leiming (institute of botany,chinese {3. of sciences, Beijing 100044,China) Inst of botany Chinese Acad of Sciences Beijing China China

ＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｐｈｏｓｐｈｏｒｕｓｃｈｅｍｉｓｔｒｙａｎｄｉｔｓｇｅｏｇｒａｐｈｉｃａｌｄｉｓｔｒｉｂｕｔｉｏｎｉｎｔｈｅＨａｉｈｅＲｉｖｅｒｖａｌｌｅｙ，ＮｏｒｔｈＣｈｉｎａＪｉａｎｇＧａｏｍｉ... 详细信息

ＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｐｈｏｓｐｈｏｒｕｓｃｈｅｍｉｓｔｒｙａｎｄｉｔｓｇｅｏｇｒａｐｈｉｃａｌｄｉｓｔｒｉｂｕｔｉｏｎｉｎｔｈｅＨａｉｈｅＲｉｖｅｒｖａｌｌｅｙ，ＮｏｒｔｈＣｈｉｎａＪｉａｎｇＧａｏｍｉｎｇ；ＨｕａｎｇＹｉｎｘｉａｏ；Ｌ...

关键词： phosphorus contents in plants geographical distribution Haihe River valley.