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Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2,LI XiaoDong2,3 & ZHANG Xin1,4 1Kavli Institute for theoretical Physics china,Chinese Academy of sciences,Beijing 100190,china 2Key Laboratory of Frontiers in theoretical Physics,Institute of theoretical Physics,Chinese Academy of sciences,Beijing 100190,china 3interdisciplinary center for theoretical study,university of science and technology of china,hefei 2.002.,china 4Department of Physics,College of sciences,Northeastern university,Shenyang 110004,china 1. Kavli Institute for theoretical Physics china Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China4. Department of Physics College of Sciences Northeastern University Shenyang 110004 China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

EFFECT OF BIAS STRESS ON NON-LINEAR INTERNAL FRICTION OF Al-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 166-171页

作者： TAN Qi university of science and technology of china,hefei,china Univ of science and technology of China Hefei China

The influence of longitudinal and torsional bias stresses on anomalous amplitude-dependent internal friction was *** longitudinal bias stress may always weaken the anomalous amplitude-dependent effect,while the torsional one may induce different effects from differ- ent directions *** stress effect exhibits only in properly heat treated and cold worked ahoy *** anomalous amplitude-dependent internal friction peaks,P_3,P_2 and P_1, are found to be related closely to slant dislocation kink ***,the application of bias stress to internal friction would be contributed to the study on dislocation structure.

关键词： internal friction bias stress anomalous amplitude effect dislocation kink

THE GROWTH THEOREM FOR STARLIKE MAPPINGS ON BOUNDED STARLIKE CIRCULAR DOMAINS

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 401-408页

作者： LIU TAISHUN (Department of Mathematics, university of science and technology of china, hefei 2.002., china)REN GUANGBIN (Department of Mathematics, university of science and technology of china, hefei 2.002., china) Univ Sci & Technol china Dept Math Anhua 230026 Peoples R China

The authors obtain the growth and covering theorem for the class of normalized biholomorphic starlike mappings on bounded starlike circular *** type of domain discussed is rather general, since the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. In the unit disc, it is just the famous growth and covering theorem for univalent *** theorem successfully realizes the initial idea of H. Cartan about how to extend geometric function theory from one variable to several complex variables.

关键词： Starlike mappings Growth theorem Starlike circular domains

THE BLOCH CONSTANT OF LOCALLY BIHOLOMORPHIC MAPPINGS ON BOUNDED SYMMETRIC DOMAINS

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 271-278页

作者： GONG SHENG(Department of Mathematics, university of science and technology of china, hefei 2.002., china) UNIV SCI & TECHNOL china DEPT MATHHEFEI 230026PEOPLES R CHINA

The estimations of the bounds of the Bloch constant of locally biholomorphic mappingson irreducible bounded symmetric domains are given. When the domain is a unit circle, theestimation of the lower bounds is just the ... 详细信息

关键词： Bounded symmetric domain Bloch mapping Bloch constant,Locally biholomorphic mapping

Epidemic dynamics on complex networks

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Progress in Natural science:Materials International 2006年第5期16卷 452-457页

作者： ZHOU Tao , FU Zhongqian, and WANG Binghong (Department of Electronic science and technology, university of science and technology of china, hefei 2.002., china Department of Modern Physics, university of science and technology of china, hefei 2.002., china) [a]Department of Electronic science and technology University of Science and Technology of China Hefei China

Recently, motivated by the pioneer work in revealing the small-world effect and scale-free property of various real-life networks, many scientists devote themselves to studying complex networks. One of the ultimate goals is to understand how the topological structures affect the dynamics upon networks. In this paper, we give a brief review on the studies of epidemic dynamics on complex networks, including the description of classical epidemic models, the epidemic spread on small-world and scale-free networks, and network immunization. Finally, perspectives and some interesting problems are proposed.

关键词： epidemic dynamics complex networks critical value immunization small-world effect scale-free property.

Some new results about Jacobi forms

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Chinese science Bulletin 1997年第3期42卷 181-183页

作者： WANG JupingDepartment of Mathematics, university of science and technology of china, hefei 2.002., china Department of Mathematics University of Science and Technology of China Hefei China

THE one-dimensional Jacobi forms were first systematically investigated by Eichler and Zagier, and a similar theory in a higher-dimensional case was developed by Ziegler, who gave the precise definition and some basic properties of higher-dimensional Jacobi forms. This note tries to give a satisfactory classification for a large kind of spaces of Jacobi forms. To be a little more explicit, we get a rank formula for Jacobi forms and then show that either all the

关键词： Jacobi forms rank coefficient estimation.

Effects of radial velocity on line profiles and images from the standard thin disk

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 155-162页

作者： PAN CaiJuan Department of Physics and Telecommunication Engineering, Baise university, Baise 533000, china center for Astrophysics, university of science and technology of china, hefei 230051, china 1. Department of Physics and Telecommunication Engineering Baise University Baise 533000 China2. Center for Astrophysics University of Science and Technology of China Hefei 230051 China

This paper has derived the general formulae of observed line profiles based on the effects of radial velocity on the standard thin disk fluid around a rotating black hole. Through the ray-tracing method the line profiles of different parameters have been calculated. Comparison of the line profiles with and without a radial velocity shows that the effects of radial velocity on line profiles cannot be neglected in most cases. In both cases the accretive disk imaging shape remains unchanged.

关键词： standard thin disk radial velocity Kerr metric line flux

TYPE X MONOTONE SYSTEMS WITH AN ORDER-INCREASING INVARIANT FUNCTION

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 335-342页

作者： JIANG JIFA(Department of Mathematics, The university of science and technology of china, hefei 230036, china.) Department of Mathematics University of Science and Technology of China Hefei 230036 China

The author considers the asymptotic behavior of solutions of a class of ordinary dmerentialequations x = F(x) in the nonnegative orthant R7. Suppose that F(o) = o, Fi(x1,..., xn) isnondecreasing in xk for all k≠ i and that F possesses an order-increasing invarian *** it is shown that every bounded solution to such a system converges to a single equilibrium.

关键词： Type K monotone system Monotone flow Invariant function Equilibrium Convergence

An experimental study on the self-adaption mechanism used by evolutionary programming

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Progress in Natural science:Materials International 2008年第4期18卷 481-486页

作者： Jingsong He a,b, a Department of Electronic science and technology, university of science and technology of china, hefei 2.002., china b Nature Inspired Computation and Application Laboratory, university of science and technology of china, hefei 2.002., china Department of Electronic science and technology University of Science and Technology of China Hefei 230027 China Nature Inspired Computation and Application Laboratory University of Science and Technology of China Hefei 230027 China

Evolutionary programming (EP) is one of the most important methods for numerical optimization. Its main technique is the combi- nation of mutations and the self-adaption mechanism. In the past years, studies on EP focused on how to improve the effciency of muta- tions with different probability distributions, and few of them touched on the question that the self-adaption mechanism did not work sometimes, but simply followed the original suggestion. So far, no experimental results have shown why this is a question. This paper firstly gives a primary analysis on the behavior of the self-adaption mechanism, and then presents experimental evidences to show why its adaptive ability is doubtful.

关键词： Evolutionary programming Cauchy mutation Self-adaption mechanism