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Property A and Uniform Embeddability of Metric Spaces Under Decompositions of Finite Depth

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Chinese Annals of mathematics,Series B 2010年第1期31卷 21-34页

作者： Yujuan DUAN Qin WANG Xianjin WANG department of Applied mathematics Donghua University Shanghai 201620 China Corresponding author. department of Applied mathematics Donghua University Shanghai 201620 China

Property A and uniform embeddability are notions of metric geometry which imply the coarse Baum-Connes conjecture and the Novikov *** this paper,the authors prove the permanence properties of property A and uniform em... 详细信息

关键词： Metric space Uniform embedding Property A Large scale decomposition Permanence property

CMC surfaces in the hyperbolic 3.space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2 and LI Zhenqi 1, 3.1. Institute of mathematics, Fudan University, shanghai 20043., china 2. {3. of mathematics,Sichuan Union University, Chengdu 610064, china 3. {3. of mathematics, Nanchang University, Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China department of mathematics Sichuan Union University Chengdu China department of mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Remarks on the Operator Norm Localization Property

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Chinese Annals of mathematics,Series B 2011年第4期32卷 593-604页

作者： Xianjin WANG department of Applied mathematics Donghua University Shanghai 201620 China.

The author studies the metric spaces with operator norm localization property. It is proved that the operator norm localization property is coarsely invariant and is preserved under certain infinite union. In the case... 详细信息

关键词： Metric space Asymptotic dimension Operator norm localization Coarse invariance Roe algebra

7th CIIE likely to prove solid growth platform for many companies

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china Textile 2024年第4期 20-21页

作者： Editorial department of china Daily

The robust demand of the Chinese market and the improving business environment in the country make china a big growth opportunity for companies wishing to further expand their operations,said corporates that have registered to participate at this year's china International Import *** 7th edition of the annual CIIE,to be held in shanghai from Nov 5 to 10,started its 100-day countdown on Saturday.

关键词： companies likely operations

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Global existence of smooth solutions to two-dimensional compressible isentropic Euler equations for Chaplygin gases

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Science china mathematics 2010年第3期53卷 719-738页

作者： KONG DeXing 1 , LIU KeFeng 2 & WANG YuZhu 3. 1 department of mathematics, Zhejiang University, Hangzhou 3.0027, china 2 department of mathematics, University of California at Los Angeles, CA 90095, USA 3.department of mathematics, shanghai Jiao Tong University, shanghai 200248, china department of mathematics Zhejiang University Hangzhou China department of mathematics University of California at Los Angeles Los Angeles USA department of mathematics Shanghai Jiao Tong University Shanghai China

In this paper we investigate the two-dimensional compressible isentropic Euler equations for Chaplygin gases. Under the assumption that the initial data is close to a constant state and the vorticity of the initial velocity vanishes, we prove the global existence of the smooth solution to the Cauchy problem for twodimensional flow of Chaplygin gases.

关键词： Chaplygin gases compressible Euler equations irrotational flow null condition Cauchy problem smooth solution

Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2 & Lü Caidian3.1. department of Physics, Lishui University, Lishui 3.3.00,china 2. department of Physics, {3. Jiaotong University, {3. 20003., china 3. Institute of High Energy Physics, Beijing 100049,china department of Physics Lishui University Lishui China department of Physics Shanghai Jiaotong University Shanghai China Institute of High Energy Physics Beijing China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Superconductivity of small metal grains

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2 & ZHU Shunquan1,3.1. department of Physics, shanghai Normal University, shanghai 20023., {3. 2. department of Physics, Southwest Normal University, Chongqing 400715, {3. 3. department of Computer and Electric Technology, shanghai Business School, shanghai 201400, {3. department of Physics Shanghai Normal University Shanghai China department of Physics Southwest Normal University Chongqing China department of Computer and Electric Technology Shanghai Business School Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural Science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2, Wu Yigen3.and Guo Shengli3.1. College of Life Sciences, Zhejiang University, Hangzhou 3.0058, china 2. Imaging department of Tongji Hospital of Tongji University, shanghai 200065, china 3. College of mathematics and Physics, Nanjing University of Information Science and Technology, Nanjing 210044, china) College of Life Sciences Zhejiang University Hangzhou 310058 China Imaging department Tongji Hospital Tongji University Shanghai 200065 China College of mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

CURVILINEAR PATHS AND TRUST REGION METHODS WITH NONMONOTONIC BACK TRACKING TECHNIQUE FOR UNCONSTRAINED OPTIMIZATION

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Journal of Computational mathematics 2001年第3期19卷 241-258页

作者： De-tong Zhu (department of mathematics, shanghai Normal University, shanghai 20023., china) 上海师范大学上海 200234

Focuses on a study which examined the modification of type approximate trust region methods via two curvilinear paths for unconstrained optimization. Properties of the curvilinear paths; Description of a method which combines line search technique with an approximate trust region algorithm; Information on the convergence analysis; Details on the numerical experiments.

关键词： curvilinear paths trust region methods nonmonotonic technique unconstrained optimization