一类奇异非线性方程的正整体解存在的充分必要条件

本文研究形如Δ^nu=f(|x|,u,|Δ↓u|u^-β，x∈R^N的奇异非线性多调和方程在R^N(N≥3)上的正整体解，给出了该方程具有无穷多个其渐进阶刚好为|x|^2n-2的正整体解的充分与必要条件。     

${\mbox{\boldmath $R$}}^N$上奇异非线性多调和方程的正整体解

本文研究形如△((△nu)(p-1) )=f(|x|,u,|(?)u|)u-β,x∈RN的奇异非线性多调和方程在RN上的正整体解,此处P>1,β≥0是常数,n是自然数,f:R × R ×R →R 是一个连续函数, ξδ*:=sign(ξ)·|ξ|δ,,ξ∈R,δ>0,给出了该类方程具有无穷多个其渐进阶刚好为|x|2n的正整体解的充分条件与必要条件.这些结论可以推广到更一般的方程.     

RN上奇异非线性多调和方程的正整体解

本文研究形如△((△nu)(p-1)*)=f(|x|,u,| u|)u-β,x∈RN的奇异非线性多调和方程在RN上的正整体解,此处p＞1,β≥0是常数,n是自然数,f:R+×R+×R+→R+是一个连续函数,ξδ*:=sign(ξ)·|ξ|δ,ξ∈R,δ＞0,给出了该类方程具有无穷多个其渐进阶刚好为|x|2n的正整体解的充分条件与必要条件.这些结论可以推广到更一般的方程.     

关于奇异非线性多调和方程的正整体解

该文主要研究形如Δ((Δ\+nu)\+\{p-1*\}) = f(|x|, u, |u|)u\+\{-β\},\ x∈R\+2的奇异非线性多调和方程在R\+2上的正整体解，此处p>1，β≥0是常数，n是自然数，f: [AKR-]\-+×R\-+×[AKR-]\-+→R\-+是 一个连续函数,ξ\+\{α*\}:=|ξ|\+\{α-1\}ξ,ξ∈R，α>0 . 证明了这种解 u必无界且其渐进阶（当n→∞时u作为无穷大量的阶）不低于|x|\+\{2n\}log|x| ，给 出了该方程具有无穷多个其渐进阶刚好为 |x|\+\{2n\}log|x| 的正整体解的充分与充分必要条件. 这些结论可以推广到更一般的方程中去.      

高阶非线性Schrdinger方程的自相似解

研究非线性项的形式为|u|~pu,p>0的2m阶非线性Schrdinger方程的自相似解.利用scaling和压缩映象原理证明了当初值满足一定条件时Cauchy问题解的整体存在性,据此给出了当初值的形式为U(x/(|x|))|x|~(-(2m)/p)时,自相似解的存在性.     

高阶非线性Schr(o)dinger方程的自相似解

研究非线性项的形式为|u|pu,p>0的2m阶非线性Schr(o)dinger方程的自相似解.利用scaling和压缩映象原理证明了当初值满足一定条件时Cauchy问题解的整体存在性,据此给出了当初值的形式为U(x/|x|)|x|-2m/p时,自相似解的存在性.     

从一道赛题得到的启示

<正>2013年全国初中数学联赛四川赛区决赛试卷中第2道选择题是"方程x2-2012|x|+2013=0的所有实数解的和为()".(A)-2012(B)0(C)2012(D)2013为了叙述方便清晰,先给出两个解法:解法1据题意,原方程就是|x|2-2012|x|+2013=0,故它的正实数解是|x|=     

一个Schrdinger-Hartree方程的解

本文讨论下列Schrdinger-Hartree方程的解其中r=|x|,v=r~(-1)*|u|~2。证明了方程的整体解v满足我们考虑下列Schrdinger-Hartree方程:其中r=|x|,v=r~(-1)*|u|~2,即     

一类带调和势的非线性Schr(O)dinger方程在RN中的整体解存在的门槛

本文考虑一类带调和势的非线性Schrodinger方程iψt=-△ψ+|x|2ψ-μ|ψ|p-1ψ-λ|ψ|q-1ψ,x∈RN,t≥0,其中μ＞0,λ＞0.当N=1,2时,1＜p＜q＜∞;当N≥3时,1＜p＜q＜N+2/N-2.运用精巧的变分方法、势井方法和凸方法,得到了方程的整体解和爆破解存在的门槛.进一步回答了:当q＞p＞1+4/N时,方程的Cauchy问题的初值小到什么程度,其整体解存在?.     

奇异半线性椭圆方程的非径向正整体解

研究如下N维奇异半线性椭圆方程△u+f(x,u)=0, x∈RN(N≥3),其中函数f:RN× R+→R+连续,在u=0有奇异性;采用上-下解方法给出该方程具有满足如下性质的有界正整体解u的条件: u∈C2+θloc(RN)使得lim |x|→∞ u(x)=0且u(x)≥εmin{1,|x|2-N},其中ε＞0是常数;并证明:若条件添加"f关于u单调不增"的限制,则这种解是唯一的.     

Existence and concentration result for Kirchhoff equations with critical exponent and Hartree nonlinearity

This paper is concerned with the following Kirchhoff-type equations $$ \left\{ \begin{array}{ll} \displaystyle -\big(\varepsilon^{2}a+\varepsilon b\int_{\mathbb{R}^{3}}|\nabla u|^{2}\mathrm{d}x\big)\Delta u + V(x)u+\mu\phi |u|^{p-2}u=f(x,u), &\quad \mbox{ in }\mathbb{R}^{3},\(-\Delta)^{\frac{\alpha}{2}} \phi=\mu|u|^{p},~u>0, &\quad \mbox{ in }\mathbb{R}^{3},\\end{array} \right. $$ where $f(x,u)=\lambda K(x)|u|^{q-2}u+Q(x)|u|^{4}u$, $a>0,~b,~\mu\geq0$ are constants, $\alpha\in(0,3)$, $p\in[2,3),~q\in[2p,6)$ and $\varepsilon,~\lambda>0$ are parameters. Under some mild conditions on $V(x),~K(x)$ and $Q(x)$, we prove that the above system possesses a ground state solution $u_{\varepsilon}$ with exponential decay at infinity for $\lambda>0$ and $\varepsilon$ small enough. Furthermore, $u_{\varepsilon}$ concentrates around a global minimum point of $V(x)$ as $\varepsilon\rightarrow0$. The methods used here are based on minimax theorems and the concentration-compactness principle of Lions. Our results generalize and improve those in Liu and Guo (Z Angew Math Phys 66: 747-769, 2015), Zhao and Zhao (Nonlinear Anal 70: 2150-2164, 2009) and some other related literature.     

Existence and non-existence of solutions to elliptic equations related to the Caffarelli–Kohn–Nirenberg inequalities

We investigate elliptic equations related to the Caffarelli–Kohn–Nirenberg inequalities: and such that . For various parameters α, β and various domains Ω, we establish some existence and non-existence results of solutions in rather general, possibly degenerate or singular settings.     

Multiple solutions for a nonhomogeneous Schrodinger-Poisson system with concave and convex nonlinearities

In this paper, we consider the following nonhomogeneous Schrodinger-Poisson equation $$ \left\{ - \Delta u +V(x)u+\phi(x)u =-k(x)|u|^{q-2}u+h(x)|u|^{p-2}u+g(x), &x\in \mathbb{R}^3,\\ \Delta \phi =u^2, \quad \lim_{|x|\rightarrow +\infty}\phi(x)=0, & x\in \mathbb{R}^3, \right. $$ where $1相似文献   

Uniqueness and existence of solutions for a singular system with nonlocal operator via perturbation method

In this work, we investigate the existence and the uniqueness of solutions for the nonlocal elliptic system involving a singular nonlinearity as follows: $$ \left\{\begin{array}{ll} (-\Delta_p)^su = a(x)|u|^{q-2}u +\frac{1-\alpha}{2-\alpha-\beta} c(x)|u|^{-\alpha}|v|^{1-\beta}, \quad \text{in }\Omega,\ (-\Delta_p)^s v= b(x)|v|^{q-2}v +\frac{1-\beta}{2-\alpha-\beta} c(x)|u|^{1-\alpha}|v|^{-\beta}, \quad \text{in }\Omega,\ u=v = 0 ,\;\;\mbox{ in }\,\mathbb{R}^N\setminus\Omega, \end{array} \right. $$ where $\Omega $ is a bounded domain in $\mathbb{R}^{n}$ with smooth boundary, $0<\alpha <1,$ $0<\beta <1,$ $2-\alpha -\beta 相似文献   

On a semilinear double fractional heat equation driven by fractional Brownian sheet

In this paper, we consider the stochastic heat equation of the form $$\frac{\partial u}{\partial t}=(\Delta_\alpha+\Delta_\beta)u+\frac{\partial f}{\partial x}(t,x,u)+\frac{\partial^2W}{\partial t\partial x},$$ where $1<\beta<\alpha< 2$, $W(t,x)$ is a fractional Brownian sheet, $\Delta_\theta:=-(-\Delta)^{\theta/2}$ denotes the fractional Lapalacian operator and $f:[0,T]\times \mathbb{R}\times \mathbb{R}\rightarrow\mathbb{R}$ is a nonlinear measurable function. We introduce the existence, uniqueness and H\"older regularity of the solution. As a related question, we consider also a large deviation principle associated with the above equation with a small perturbation via an equivalence relationship between Laplace principle and large deviation principle.     

Convergence of Solutions of General Dispersive Equations Along Curve

In this paper, the authors give the local L~2 estimate of the maximal operator S_(φ,γ)~* of the operator family {S_(t,φ,γ)} defined initially by ■which is the solution(when n = 1) of the following dispersive equations(~*) along a curve γ:■where φ : R~+→R satisfies some suitable conditions and φ((-?)~(1/2)) is a pseudo-differential operator with symbol φ(|ξ|). As a consequence of the above result, the authors give the pointwise convergence of the solution(when n = 1) of the equation(~*) along curve γ.Moreover, a global L~2 estimate of the maximal operator S_(φ,γ)~* is also given in this paper.     

具位势项的快扩散方程的第二临界指标

This paper considers a fast diffusion equation with potential ut= um V (x)um+upin Rn×(0,T), where 1 2αm+n< m ≤ 1, p > 1, n ≥ 2, V (x) ～ω|x|2with ω≥ 0 as |x| →∞,and α is the positive root of αm(αm + n 2) ω = 0. The critical Fujita exponent was determined as pc= m +2αm+nin a previous paper of the authors. In the present paper,we establish the second critical exponent to identify the global and non-global solutions in their co-existence parameter region p > pcvia the critical decay rates of the initial data.With u0(x) ～ |x| aas |x| →∞, it is shown that the second critical exponent a =2p m,independent of the potential parameter ω, is quite different from the situation for the critical exponent pc.     

Uniqueness of Positive Solutions for a Nonlinear Elliptic System

In this paper we study the uniqueness of nontrivial positive solutions for the following second order nonlinear elliptic system:

带有负指数 Kirchhoff 方程稳定解的Liouville型定理

In this paper, we consider the Liouville-type theorem for stable solutions of the following Kirchhoff equation ■,where M(t) = a + bt~θ, a 0, b, θ≥ 0, θ = 0 if and only if b = 0. N ≥ 2, q 0 and the nonnegative function g(x) ∈ L_(loc)~1(R~N). Under suitable conditions on g(x), θ and q, we investigate the nonexistence of positive stable solution for this problem.