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STEADY-STATE SOluTIONS FOR A ONE-DIMENSIONAL NONISENTROPIC HYDRODYNAMIC MODEL WITH NON-CONSTANT LATTICE TEMPERATURE

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Acta Mathematica Scientia 2008年第3期28卷 479-488页

作者：黎野平 department of mathematics Xianning College

A one-dimensional stationary nonisentropic hydrodynamic model for semiconductor devices with non-constant lattice temperature is studied. This model consists of the equations for the electron density, the electron current density and electron temperature, coupled with the Poisson equation of the electrostatic potential in a bounded interval supplemented with proper boundary conditions. The existence and uniqueness of a strong subsonic steady-state solution with positive particle density and positive temperature is established. The proof is based on the fixed-point arguments, the Stampacchia truncation methods, and the basic energy estimates.

关键词： Steady-state nonisentropic hydrodynamic model semiconductor subsonic

Third-order optical nonlinearities for lanthanum (Ⅲ) complexes with 1,10-phenanthroline components

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Chinese Science Bulletin 1998年第5期43卷 399-402页

作者： SUN Zhenrong, WANG Shenyi, HUANG Yanping, LIN Jiyun,DING Liangen and WANG ZugengLaboratory for Quantum Optics, east china normal university, National Education Commission department of Physics, east china normal university, shanghai 200062, china Laboratory for Quantum Optics East China Normal University National Education Commission China department of Physics East China Normal University Shanghai China

The nonlinear refractive indexes n 2 for the ethanol solutions of 1,10-phenanthroline (2.0×10 -3 mol·L -1), [bis(1,10-phenanthroline) lanthanum (Ⅲ)] nitrate (1.0×10 -3 mol·L -1), and [nitrato-fluoracil-bis (1,10-phenanthroline) lanthanum (Ⅲ)] nitrate (1.0×10 -3 mol·L -1) are first measured, the third-order nonlinear optical susceptibilities χ (3) and are calculated, and the mechanisms of the third-order optical nonlinearities enhanced by lanthanum (Ⅲ) are discussed preliminarily.

关键词： Z-scan third-order optical nonlinearity lanthanum (Ⅲ) 1 10-phenanthroline.

A NONLINEAR GALERKIN METHOD WITH VARIABLEMODES FOR KURAMOTO-SIVASHINSKY EQUATION

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Journal of Computational mathematics 1999年第3期17卷 243-256页

作者： Yu-jiang wu(Depadrtment of mathematics, shanghai university, Jiadiap shanghai 201800, china department of mathematics, Lanzhou university, Lanzhou 750000, china) 上海大学数学系上海

This article proposes a kind of nonlinear Galerkin methods with variable modes for the long-term integration of Kuramoto-Sivashinsky equation. It consists of finding an appropriate or best number of modes in the correction of the method. Convergence results and error estimates are derived for this method. Numerical examples show also the efficiency and advantage of our method over the usual nonlinear Galerkin method and the classical Galerkin method.

关键词： Kuramoto-Sivaskinsky equation nonlinear Galerkin method approximation convergence

The rule of sediment transport on the Nanhui tidal flat in the changjiang Estuary

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Acta Oceanologica Sinica 1991年第1期10卷 117-127页

作者： Li Jiufa Institute of Estuarine and Coastal Research, east china normal university, shanghai, 200062, china

The Nanhui tidal flat is located in the area of slow current where the ebb currents from the changjiang Estuaryand the Hangzhou Bay converge and the flood current from the sea diverges into the estuary and the bay. The flat extends seaward in tongue shape and has a wide and gentle surface with a marked difference of tidal levels on its two sides, which results in the sediment longitudinal transport on the flat. The water-sediment conditions are diverse at different locations. The velocity and sediment concentration in intertidal zone are higher during the flood tide than those during the ebb tide. The net sediment transport is landward, resulting in a large amount of deposition of sediments on the shoal. However, the ebb current is the dominant one in deep-water area where the net sediment transport is seaward. There exist two circulation systems in plane view on the shoal and in its adjacent deep-water area, which results in the sediment exchanges between the flat and channel and between the estuary and the bay. The landward storm waves erode shoal face, causing the rise of water level on the flat, originating the formation of the vertical circulation system of the sediment transport, and consequently * accelerating the evolution process of the tidal flat.

关键词： The rule of sediment transport on the Nanhui tidal flat in the changjiang Estuary

FREE-SURFACE WAVES AND FAR WAKES GENERATED BY A FLOATING BODY IN A VISCOUS FluID

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Journal of Hydrodynamics 2003年第4期15卷 10-16页

作者： lu Dong-qiang department of Mechanical Engineering, The university of hong Kong, hong Kong, china shanghai Institute of Applied mathematics and Mechanics, shanghai university, shanghai 200072, china Dept. of Mech. Eng. Univ. of Hong Kong Hong Kong Hong Kong Inst. of Appl. Math. and Mech. Shanghai Univ. Shanghai 200072 China

The free-surface waves and the flow field due to a body moving on the surfaceof an incompressible viscous fluid of infinite depth were studied analytically. The floating bodywas modeled as a normal point pressure on the free surface. Based on the Oseen approximation forgoverning equations and the linearity assumption for boundary conditions, the exact solutions inintegral form for the free-surface elevation, the velocities and the pressure were given. Byemploying Lighthill's two-stage scheme, the asymptotic representations in far field for largeReynolds numbers were derived explicitly. The effect of viscosity on the wave profiles was expressedby an exponential decay factor, which removes the singular behavior predicted by the potentialtheory.

关键词： free-surface waves velocity distribution floating body viscosity asymptotic representation light-hill's two-stage scheme

A NOTE ON THE RELATIVE CANONICAL IMAGE OF A NON-HYPERELLIPTIC FIBRATION OF GENUS

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Chinese Annals of mathematics,Series B 1994年第2期15卷 157-164页

作者： CHEN ZHIJIE(department of Matehematics,east normal university, shanghai 00062, china) E china normal UNIV DEPT MATHSHANGHAI 200062PEOPLES R CHINA

This paper investigates the relative 1-canonical images of non-hyperelliptic fibrations of genus 4. It is proved that if a fibre of the relative 1-canonical image ∑ is not a complete intersection in 3 , then the var... 详细信息

关键词： Genus Non-hyperelliptic fibration Canonical image Algebraic variety.

THE GPL-STABILITY OF RUNGE-KUTTA METHODS FORDELAY DIFFERENTIAL SYSTEMS

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Journal of Computational mathematics 2000年第1期18卷 75-82页

作者： Biao Yang Lin Qiu Jiao-xun Kuang(department of mathematics, shanghai normal university, shanghai 200234, china.) 上海师范大学上海 200234

Presents a study which dealt with stability of the implicit Runge-Kutta methods for the numerical solutions of the systems of delay differential equations. Stability behavior of the methods; Exponential solutions of t... 详细信息

关键词： delay differential equation implicit Runge-Kutta methods GPL-stability

Back-scattering from rough sea surface with foams

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Acta Oceanologica Sinica 1993年第4期12卷 563-572页

作者： Jin Yaqiu, Huang Xingzhong and Yin Jieyi department of Electronic Engineering, Fudan university, shanghai 200433, china department of Electronic Science, china east normal university, shanghai 200062, china Dept of Electronic Engineering Fudan University Shanghai 200433 China China

By using iterative method to solve the vector radiative transfer equation of discrete scatterers with randomly rough under-boundary, the back-scattering coefficient is derived, and is applied to the two-scale model of sea surface with foam scatterers driven by strong wind. By employing the modified probability density function of Cox and Munk's, and Pierson's sea spectrum, numerical results of polarized back-scatter ing are calculated. The functional dependence on wind speed and direction, observation angle, polarization and other parameters are discussed, and theoretical results are favorably matched with experimental data.

关键词： Radiative transfer two-scale randomly rough surface back-scattering wind

A differentiable sphere theorem with positive Ricci curvature and reverse volume pinching

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Science china mathematics 2011年第3期54卷 603-610页

作者： WANG PeiHe1 & WEN YuLiang2 1School of Mathematical Sciences, Qufu normal university, Qufu 273165, china 2department of mathematics, east china normal university, shanghai 200241, china School of Mathematical Sciences Qufu Normal University Qufu China department of mathematics East China Normal University Shanghai China

Let Mn be a compact, simply connected n (≥3)-dimensional Riemannian manifold without bound-ary and Sn be the unit sphere Euclidean space Rn+1. We derive a differentiable sphere theorem whenever themanifold concerned satisfies that the sectional curvature KM is not larger than 1, while Ric(M)≥n+2 4 and the volume V (M) is not larger than (1 + η)V (Sn) for some positive number η depending only on n.

关键词： k-th Ricci curvature Hausdorff convergence differentiable sphere theorem harmonic coordinate harmonic radius