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Complete multiple round quantum dense coding with quantum logical network

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Chinese Science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2,LI XiHan1,2,DENG FuGuo1,2,3,ZHOU Ping1,2 & ZHOU HongYu1,2,3 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,beijing normal university,beijing 100875,china 2 Institute of Low Energy Nuclear Physics,and department of Material Science and Engineering,beijing normal university,beijing 100875,china 3 beijing Radiation Center,beijing 100875,china Key Laboratory of Beam Technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠

Automatic generalization of metro maps based on dynamic segmentation

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Science china(Technological Sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2 & ZHANG Yi 2 1 Institute of Geography and Remote Sensing,beijing normal university,beijing 100875,china 2 Institute of Remote Sensing and Geographic Information System,Peking university,beijing 100871,china 1. Institute of Geography and Remote Sensing Beijing Normal University Beijing 100875 China 2. Institute of Remote Sensing and Geographic Information System Peking University Beijing 100871 China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

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Science china(Physics,Mechanics & astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2 1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing normal university, beijing 100875, china 2. Peking university, Physics School, beijing 100871, china Applied Optics beijing Area Major Laboratory Analysis testing center Beijing Normal University Beijing 100875 China Physics School Peking University Beijing 100871 China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2(Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2(Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Compactness of the commutators of parabolic singular integrals

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Science china Mathematics 2010年第10期53卷 2633-2648页

作者： CHEN YanPing1 & DING Yong2,3 1department of Mathematics and Mechanics,university of Science and Technology beijing,beijing 100083,china 2School of Mathematical Science,beijing normal university,beijing 100875,china 3Laboratory of Mathematics and Complex Systems (BNU),Ministry of Education of china,beijing 100875,china 1. department of Mathematics and Mechanics University of Science and Technology Beijing Beijing 100083 China2. School of Mathematical Science Beijing Normal University Beijing 100875 China3. Laboratory of Mathematics and Complex Systems (BNU) Ministry of Education of China Beijing 100875 China

In this paper,the authors prove that the commutator [b,T] of the parabolic singular integrals is a compact operator on Lp(Rn)(1 < p < ∞) if and only if b ∈ VMO(Rn,ρ).The result is substantial improvement and extens... 详细信息

关键词： parabolic singular integrals commutators compactness BMO VMO

Constraints on smoothness parameter and dark energy using observational H(z) data

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Research in astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2,Tong-Jie Zhang1,3 and Bao-Quan Wang4 1 department of astronomy,beijing normal university,beijing 100875,china 2 Business Office,beijing Planetarium,beijing 100044,china 3 Center for High Energy Physics,Peking university,beijing 100871,china 4 department of Physics,Dezhou university,Dezhou 253023,china department of astronomy Beijing Normal University Beijing 100875 China Business Office Beijing Planetarium Beijing 100044 China Center for High Energy Physics Peking University Beijing 100871 China department of Physics Dezhou University Dezhou 253023 China

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2 minimization method,we get α = 0.81＋0.19-0.20 and ΩM = 0.32＋0.12-0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.26 ± 0.1,we get α = 0.93＋0.07-0.19 and ΩM = 0.31＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

Refraction of light in media

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Science china(Physics,Mechanics & astronomy) 2007年第5期50卷 591-600页

作者： ZHANG Tao Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, beijing normal university, beijing 100875, china beijing Radiation Center, beijing 100875, china Key Laboratory of Beam Technology Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China

The roles of the magnetic field and electric field of the light are investigated when the light is refracted in the medium. The model of the electron cloud conductor is presented. Electron cloud in a molecule is treated as a conductor and the Faraday’s Law is applied to this conductor that is in the alternating magnetic field of the light. dBM/dt of the light gives rise to an alternating induced current on the electron cloud conductor, and the light exchanges energy, i.e. the refractive energy, with the elec- tron cloud conductor. Formulas of refractive index, which is the ratio of light speed in vacuum to that in the medium, are derived with this model. These formulas are tested with several mediums and Langevin’s diamagnetic susceptibility of helium gas, and the results are in good agreement with the measured data. The anisotropy and the nonlinearity of the refractive index are explained with the theory described in this work.

关键词： refractive index, light, speed, medium, propagation

STUDY OF Ag DIFFUSION INTO Cu SINGLE CRYSTALS BY RUTHERFORD BACKSCATTERING SPECTROMETRY

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 332-334页

作者： R.Wang 1) Key Laboratory of Beam Technology and Materials Modification, Ministry of Education, beijing 100875, china2) Institute of Low Energy Nuclear Physics, beijing normal university, beijing 100875, china3) beijing Radiation Center, beijing 100875, china Key Laboratory of Beam Technology and Materials Modification Ministry of Education Beijing 100875China Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China

4.0Me V 7Li++ RBS was used for investigations of thermal diffusion of Ag in Cu single crystals. The annealing of samples was carried out in vacuum in the temperature range from 498K to 613K. The element depth concentration profiles transformed from RBS spectra indicate that the diffusion of Ag into Cu is a typical volume diffusion. The Arrhenius parameters corresponding to the diffusion were obtained.

关键词： Ag diffusion single crystal

Representation type of 0-Hecke algebras

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Science china Mathematics 2011年第3期54卷 411-420页

作者： DENG BangMing1 & YANG GuiYu2,1department of Mathematics, beijing normal university, beijing 100875, china 2School of Science, Shangdong university of Technology, Zibo 255049, china 1. department of Mathematics Beijing Normal University Beijing 100875 China2. School of Science Shangdong University of Technology Zibo 255049 China

In the present paper we determine the representation type of the 0-Hecke algebra of a finite Coxeter group.

关键词： Coxeter group 0-Hecke algebra representation type

Ergodicity of Reversible Reaction Diffusion Processes with General Reaction Rates

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Acta Mathematica Sinica,English Series 1994年第1期10卷 99-112页

作者： Chen Mufa Ding Wanding Zhu Dongjin department of Mathematics beijing normal university beijing,100875 china department of Mathematics Animi normal university Wuhu,241000 china 1. department of Mathematics Beijing Normal University 100875 Beijing China 2. department of Mathematics Anhui Normal University 241000 Wuhu China

In this paper,a class of reaction diffusion processes with general reaction rates is studied.A necessary and sufficient condition for the reversibility of this calss of reaction diffusion processes is given,and then t... 详细信息

关键词： Ergodicity of Reversible Reaction Diffusion Processes with General Reaction Rates