高阶Schrdinger方程的加权估计

本文主要研究的是相函数为齐次椭圆多项式的自由高阶 Schrdinger 方程．通过相函数等值面的几何性质,得到了解算子的 Strichartz 加权估计和极大算子加权估计．     

一类非线性Schr(o)dinger方程的整体小解

本文研究带有非线性项|u|~pu的高阶非线性Schr(?)dinger方程的Cauchy问题．对于p的某一取值范围。我们证明了此问题整体解的存在唯一性,并得到了解关于初值的连续依赖性及解具有较强的衰减估计。     

一类Schrdinger方程的局部光滑估计

本文利用L2的球调和分解和Hankel变换得到一类Schr dinger方程解的局部光滑估计.     

p-Laplace Schrdinger热方程的椭圆型梯度估计

本文对p-Laplace Schr(o|¨)dinger热方程正连续弱解做了椭圆型梯度估计;作为应用,本文得到了一个关于p-Laplace算子的Liouville型结果;并证明了关于p-LaplaceSchr(o|¨)dinger热方程正连续弱解的Harnack不等式.     

一类具非线性二阶导数项的Schr dinger方程整体解存在的最佳条件

本文讨论一类具非线性二阶导数项的Schr(?)dinger方程,它在物理上描述了上混合振荡传播．根据基态的变分特征,运用势井方法和凹方法,我们获得了其初值问题整体解存在的一个最佳条件,另外还证明了当初值多小时,初值问题的整体解存在．     

Carlemam估计的新方法及其应用

利用一种新的方法,建立了Ｔｒｉｃｏｍｉ算子的强唯一延拓性．并对具临界位势的Ｔｒｉｃｏｍｉ算子与 Ｓｃｈｒｏｄｉｎｇｅｒ算子的强唯一延拓性得到了一些肯定性的结果．     

二阶微分算子的一个注记

此文利用黎曼几何的知识将二阶椭圆算子表示成为一个Schr(?)dinger算子．     

一类KdV非线性Schr(o)dinger组合微分方程组时间周期解的存在性

本文研究了一类KdV非线性Schr(o)dinger组合微分方程组时间周期解的问题,首先利用Galerkin方法构造近似时间周期解序列,然后利用先验估计和Leray-Schauder不动点原理,证明近似时间周期解序列的收敛性,从而得到该问题时间周期解的存在性.     

一类具有临界指数的对数Schr?dinger方程基态解的存在性和集中性

本文研究一类具有竞争位势和临界指数的对数Schr?dinger方程,它的能量泛函在其自然Sobolev空间中没有一阶连续导数.首先利用非光滑临界点理论,获得相关的自治对数Schr?dinger方程基态解的存在性;然后,通过引入一个合适的基态能量函数,利用Nehari流形方法研究位势函数与对数Schr?dinger方程基态解存在性和集中性的关系;最后,给出此类方程基态解不存在的一个充分条件.     

由Schr?dinger算子定义的Riesz变换的Lp估计

本文主要讨论了当非负位势 V(x)属于某逆Holder类时,由一致椭圆算子L=-div(A(x))+V(x)所定义的 Riesz变换在 L^p空间的有界性。     

黎曼流形上薛定谔方程的Harnack估计

推导了薛定谔方程正解的一种新的整体梯度估计和Harnack不等式,推广了一些有关热方程的结论,并且得到了一个关于薛定谔算子的刘维尔定理.     

Weighted and Maximally Hypoelliptic Estimates for the Fokker-Planck Operator with Electromagnetic Fields

We consider a Fokker-Planck operator with electric potential and electromagnetic fields.We establish the sharp weighted and subelliptic estimates,involving the control of the derivatives of electric potential and electromagnetic fields.Our proof relies on a localization argument as well as a careful calculation on commutators.     

一类非牛顿渗流方程爆破界的估计

本文利用拟线性常微分方程解的非存在性定理得到了一类拟线性反应扩散方程(非牛顿渗流方程)爆破界的估计,从而推广了半线性反应扩散方程(牛顿渗流方程)相应结果.     

Gradient Estimates for a Nonlinear Diffusion Equation on Complete Manifolds

This paper deals with the gradient estimates of the Hamilton type for the positive solutions to the following nonlinear diffusion equation:u_t = △u +▽φ·▽u+a(x)uln u + b(x)u on a complete noncompact Riemannian manifold with a Bakry-Emery Ricci curvature bounded below by- K(K ≥ 0),where φ is a C~2 function,a(x) and b(x) are C~1 functions with certain conditions.     

Gradient Estimates for a Nonlinear Diffusion Equation on Complete Manifolds

Let （M,g） be a complete non-compact Riemannian manifold with the m- dimensional Bakry-Emery Ricci curvature bounded below by a non-positive constant. In this paper, we give a localized Hamilton-type gradient estimate for the positive smooth bounded solutions to the following nonlinear diffusion equation ut = △u - △↓ φ· △ ↓u - aulogu- bu,where φ is a C^2 function, and a ≠ 0 and b are two real constants. This work generalizes the results of Souplet and Zhang （Bull. London Math. Soc., 38 （2006）, pp. 1045-1053） and Wu （Preprint, 2008）.     

Derivative Estimates for the Solution of Hyperbolic Affine Sphere Equation

Considering the hyperbolic affine sphere equation in a smooth strictly convex bounded domain with zero boundary values, the sharp derivative estimates of any order for its convex solution are obtained.     

Error Estimates for Mixed Finite Element Methods for Sobolev Equation

1 IntroductionLet fl be a bounded domain in R2 with Lipschitz continuous boundaxy 0fl. For thed0 < T < co, we consider the fo1lowing initial-boun'lar}-ralue problem for thc Sobolevequation:where ut denotes the time derivative of the function (1. Vu denotes the gradient of thefunction u, and divv denotes the divergence of the vect{Jr tulued function v, a1 b1, f, anduo are known functions.The standard finite element method for (1.1) (1.3) llas received considerable attentionand is well studied…     

Estimates for multiparameter maximal operators of Schrödinger type

Multiparameter maximal estimates are considered for operators of Schrödinger type. Sharp and almost sharp results, that extend work by Rogers and Villarroya, are obtained. We provide new estimates via the integrability of the kernel which naturally appears with a TT^?$T{T}^{?}$ argument and discuss the behavior at the endpoints. We treat in particular the case of global integrability of the maximal operator on finite time for solutions to the linear Schrödinger equation and make some comments on an open problem.     

Some Gradient Estimates and Liouville Properties of the Fast Diffusion Equation on Riemannian Manifolds*

In the paper, the authors provide a new proof and derive some new elliptic type (Hamilton type) gradient estimates for fast diffusion equations on a complete noncompact Riemannian manifold with a fixed metric and along the Ricci flow by constructing a new auxiliary function. These results generalize earlier results in the literature. And some parabolic type Liouville theorems for ancient solutions are obtained.