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THE HAUSDORFF MEASURE FOR THE SAMPLE PATH OF THE WESTWATER PROCESS

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chinese Annals of Mathematics,Series B 1996年第3期17卷 375-388页

作者： ZHOU XIANYIN(Depatment of Mathematics, beijing Normal university beijing 100875, China) beijing NORMAL UNIV DEPT MATHBEIJING 100875PEOPLES R CHINA

It is proved that φ(s) = s2 log |logs| is the correct function to give the Hausdorff measureof a sample path of the Westwater process.

关键词： Hausdorff measure Wiener process Westwater process Sojourn time

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

Analysis of a kind of quantum cryptographic schemes based on secret sharing

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2 1 College of Computer Science and Technology, beijing university of Technology, beijing 100124, China 2 State Key Laboratory of Information Security, Graduate university of chinese Academy of Sciences, beijing 100049, China College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing

Studies on the Characteristics of Foliar Surfaces of Hippophae and Related Taxonomy

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北京林业大学学报 1992年第S2期14卷 64-69页

作者： Zhang ZhixiangForest Resources College, beijing forestry university

Trichome forms and stomatal distribution and types were undertaken. The results show that trichome forms are stellate, peltate and stellate-peltate. There is a difference in the position of stomata among the taxa of Hippophae. H. thibetana, H. salici-folia. H. gyantsensis, H. neurocarpa and H. rhamnoides ssp. turkestanica have stomata on both foliar surfaces, while other subspecies have stomata only on the lower surface. Stomata are of the Actinocytic type.

关键词： Hippophae. trichome stomata epidermis

Effects of Water Stress on Tissue Elasticity in Nine Tree Species

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北京林业大学学报 1992年第S2期14卷 25-32页

作者： Li JiyueForest Resources College,beijing forestry university

The experiments were carried out under the conditions of controlled soil water potential in a greenhouse. The effects of water stress on tissue elasticity were studied in 1 - 3 year-old seedlings Pinus tabulaeformis, Platycladus orientalis, Quercus variabilis, Acer truncatum , Robinia psendoacacia, Fraxinus americana , Amorpha fruticosa, Hip-pophea rahmnoides and Cotinus coggygria ,using the pressure-volume method. Tissue elasticity was characterized using graphs of the modulus of elasticity plotted as a function of turgor pressure and maximum values of the elastic modulus. Changes in tissue elasticity may be an important characteristic allowing low water potentials to be reached and maintained without the development of detrimental water stress. The results show that tissue e-lasticity in needle-leaved tree species is higher than in broad-leaved tree species,but the modulus of elasticity of the tree species tend to increase following development of water stress. Increases in elastic modulus

关键词： water stress water potential turgor elastic modulus pressure-volume

Infall and Outflow Activities in the Be star FY CMa

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chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 514-524页

作者： Hui-Lai Cao National Astronomical Observatories, chinese Academy of Sciences, beijing 100012 CAS-PKU Joint beijing Astrophysics Center, Peking university, beijing 100871 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 []CAS-PKU Joint Beijing Astrophysics Center Peking University Beijing 100871

Unusual activity of outflow mass motion connected with infall events was recorded for the B0.5 IVe star FY CMa in February 1987 from both archival IUE spectrograms of circumstellar N v resonance lines and optical spectra of Ha and HeI γ5876 A emission lines which showed inverse P Cygni-type profiles. We estimate the mass loss rate using ultraviolet Si IVresonance lines with expanding atmosphere modeling calculations, and describe how the radial pressure performs the dominant role in accelerating the stellar wind. We attempt to give a qualitative explanation for the activity observed for FY CMa in terms of circumstellar matter raining down to the star.

关键词： line: proffles - stars: activity - stars: emission-line Be -circumstellar matter - stars: mass-loss - ultraviolet: stars

Study on Sulfide-melt Inclusions in Mantle Xenoliths of Xinchang, Zhejiang

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 5-9页

作者： Jiuhua Xu Xuelei Chu YulingXie Fenglei Bie Dayi Qian university of Science and Technology beijing, beijing 100083, China China university of Geosciences, beijing 100083, China The Research Center of Mineral Resources Exploration, chinese Academy Univ Sci & Technol beijing Beijing 100083 Peoples R China China Univ Geosci Beijing 100083 Peoples R China chinese Acad Sci Res Ctr Mineral Resources Explorat Beijing 100101 Peoples R China chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

In minerals of mantle xenoliths captured within Tertiary alkali-basalt from Xinchang, Zhejiang province, China, many sulfidemelt inclusions were found by the observation of polished thin section. Electron microprobe analysis has been applied to detect the components of sulfide-melt inclusions. The result shows that the sulfide phases of inclusions are mainly pentlandite, and secondarily pyrrho- tite, The molar ratio of Ni to Fe, r_Ni,/r_Fe, of mineral phases in sulfide inclusions is related to olivine contents in host mantle xenoliths. The r_Ni/r_Ni, of sulfides from Xinchang samples has a possitive correlation to r_(Fe+Ni),/r_S. The r_(Fe+Ni),/r_S, becomes higher with the increasing of r_Ni/r_Fe In single sulfide-melt inclusions, r_Ni,/r_Fe, r_(Fe+Ni),/r, and Ni contents increase from the center to edge, reflecting a result of different cooling speed in an inclusion. A comparison between the data from Hannuoba, West Eifel of Germany and Nograd-Gomor of east Europe suggests that the composition of the inclusions is different for each area, which indicated that a regional differentiation of sulfide in mantle fluids.

关键词： mantle xenolith sulfide-melt inclusion electron microprobe analysis, Xinchang

Choice of Species in China's Plantation forestry

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北京林业大学学报 1992年第S2期14卷 15-24页

作者： Shen GuofangForest Resources College, beijing forestry university

This paper reviews the new developments in the choice of tree species for China’s plantation forestry in relation to forest regionalization and site classification. After a brief discussion on the fundamental principles of choosing species,it gives the statistical data of the species composition of established forest plantations and recommendation for suitable tree species for plantations in some important forestry regions. Results of studies in 3 different cases have been given to illustrate the research approach in choice of tree species in accordance with the planting sites.

关键词： choice of species forest regionalization site classification

Consumptive water use in cropland and its partitioning:A high-resolution assessment

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Science China(Technological Sciences) 2009年第11期52卷 3309-3314页

作者： LIU JunGuo1,2 1 School of Nature Conservation, beijing forestry university, beijing 100083, China 2 International Institute for Applied Systems Analysis, Schlossplatz 1, A-2361, Laxenburg, Austria School of Nature Conservation Beijing Forestry University Beijing 100083 China International Institute for Applied Systems Analysis Schlossplatz 1 A-2361 Laxenburg Austria

Spatially explicit assessments of consumptive water use (CWU) are still at an early stage, and parti-tioning of CWU has rarely been studied on large scales. In this article, CWU is assessed for China's cropland with a spatial resolution of 30 arc-minutes. The partitioning of CWU is discussed through the simulation of transpiration ratios. The total CWU for chinese cropland was 839 km3/a during 1998―2002. Spatial distribution of CWU is closely related to cropland area and crop production with the highest CWU in the North China Plain. Transpiration accounts for two-thirds of CWU. The transpiration ratio is affected by precipitation and irrigation. Transpiration ratios are higher in irrigated systems than in rainfed systems when precipitation is low. Competition of water use will impose pressure on China's irrigation systems in the near future, and it will have a far-reaching effect on the partitioning of consumptive water use. Attention should be paid to green water management and technological improvements to guarantee China's water and food security.

关键词： GEPIC evapotranspiration evaporation transpiration transpiration ratio China