GLOBAL EXISTENCE OF SOLUTIONS OF CAUCHY PROBLEM FOR GENERALIZED BBM-BURGERS EQUATION

In this paper, the existence and the uniqueness of the local generalized solution and the local classical solution of the Cauchy problem for the generalized BBM-Burgers equationare proved. The existence and the uniqueness of the global generalized solution and the global classical solution for the Cauchy problem of equation （1） are proved when n = 3, 2, 1. Moreover, the decay property of the solution is discussed.

PERIODIC BOUNDARY VALUE PROBLEM AND CAUCHY PROBLEM OF THE GENERALIZED CUBIC DOUBLE DISPERSION EQUATION

In this article, the existence, uniqueness and regularities of the global generalized solution and global classical solution for the periodic boundary value problem and the Cauchy problem of the general cubic double dispersion equationutt - uxx - auxxtt ＋ bux4 - duxxt = f（u）xxare proved, and the sufficient conditions of blow-up of the solutions for the Cauchy problems in finite time are given.

Spectral Method for Three-Dimensional Nonlinear Klein-Gordon Equation by Using Generalized Laguerre and Spherical Harmonic Functions

In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve the same conservation as that for the exact solution.The stability and convergence of the proposed scheme are proved.Numerical results demonstrate the efficiency of this approach.We also establish some basic results on the generalized Laguerre-spherical harmonic orthogonal approximation,which play an important role in spectral methods for various problems defined on the whole space and unbounded domains with spherical geometry.

Cauchy Problems for KdV-type Equations and Higher-Order Conditional Symmetries

<Abstract>We develop the generalized conditional symmetry (GCS) approach to solve the problem of dimensional reduction of Cauchy problems for the KdV-type equations.We characterize these equations that admit certain higher- order GCSs and show the main reduction procedure by some examples.The obtained reductions cannot be derived within the framework of the standard Lie approach.

Symmetry Reduction and Cauchy Problems for a Class of Fourth-Order Evolution Equations

We exploit higher-order conditional symmetry to reduce initial-value problems for evolution equations toCauchy problems for systems of ordinary differential equations (ODEs).We classify a class of fourth-order evolutionequations which admit certain higher-order generalized conditional symmetries (GCSs) and give some examples to showthe main reduction procedure.These reductions cannot be derived within the framework of the standard Lie approach,which hints that the technique presented here is something essential for the dimensional reduction of evolu tion equations.

Cauchy Problem of the Singularly Perturbed Sixth Order Boussinesq Type Equation

In this paper, the existence and uniqueness of the global generalized solution and the global classical solution for the Cauchy problem of the singularly perturbed sixth order Boussinesq type equation are proved.

Existence, Uniqueness and Blow-up of Generalized Solutions to General Nonlinear Filtration Equations

在这份报纸，我们为一般非线性的过滤方程 ut-Dj 考虑 nonnegative 答案到 Cauchy 问题( aij ( x ， t ， u ) Di (u)) +bi ( t ， u ) Diu+C ( x ， t ， u ) =0 ，并且获得存在，在在一些结构条件下面的这些答案的有限时间的唯一和发作。

The Cauchy problem for the stochastic generalized Benjamin-Ono equation

The current paper is devoted to the Cauchy problem for the stochastic generalized Benjamin-Ono equation.By establishing the bilinear and trilinear estimates in some Bourgain spaces,we prove that the Cauchy problem for the stochastic generalized Benjamin-Ono equation is locally well-posed for the initial data u0(x,w)∈L^(2)(Ω;H^(s)(R))which is F0-measurable with s≥1/2-α/4 andΦ∈L20,s.In particular,whenα=1,we prove that it is globally well-posed for the initial data u0(x,w)∈L2(Ω;H1(R))which is F0-measurable andΦ∈L20,1.The key ingredients that we use in this paper are trilinear estimates,the Ito formula and the Burkholder-Davis-Gundy(BDG)inequality as well as the stopping time technique.

广义Kawahara方程的Cauchy问题

对初值在Besov空间中的广义Kawahara方程(?)_tu+αu^k(?)_xu+β(?)_x^3u+γ(?)_x^5u=0进行了研究,其中k是大于4的正整数,证明了对任意的1≤q≤∞,其Cauchy问题在Besov空间B_(2,q)^(sk)(R)和B_(2,q)~s(R)中局部适定,这里s_k=(k-8)/2k,s＞max(0,s_k)；对小初值问题几乎整体适定．并证明了如果β=0或βγ＜0,对小初值问题整体适定．

具阻尼的高维广义Boussinesq方程的Cauchy问题的整体适定性

研究了一类具阻尼的高维广义Boussinesq方程utt-Δu-Δutt＋Δ2u-kΔut=Δf（u）的Cauchy问题,在没有建立问题局部解存在性理论的情况下,利用位势井方法分析了阻尼系数k与初值及井深之间的关系,得到了整体解存在与不存在的门槛结果.

一般非线性扩散方程Cauchy问题广义解的渐近性质

本文研究了比较一般的非线性扩散方程的Cauchy问题广义解的渐近性质.利用试验函数与积分估计的方法,获得了广义解当t→∞时的渐近性质以及其广义整体解u(x,t),推广了该类方程Cauchy问题广义解的性质.

一类广义BBM-Burgers方程的Cauchy问题

证明了广义BBM-Burgers方程的Cauchy问题vt-αvxxt-βvxx+γvxxxx+f(v)x=G(v)+h(vx)x+g(v)xx,x∈R,t>0,v(x,0)=v0(x),x∈R存在唯一整体强解v∈C([0,∞);Hs(R))∩C1([0,∞);Hs-2(R))(s≥4)和唯一的整体古典解,并给出解的衰减估计.

一类广义Boussinesq型方程的Cauchy问题

证明了一类广义Boussinesq型方程Cauchy问题整体解的存在性与唯一性,并给出解在有限时刻爆破的充分条件.

非线性波方程Cauchy问题整体解的存在性和非存在性(英文)

考虑非线性波方程utt-2kuxxt=g(ux)x的Cauchy问题,其中,k>0为实数,g(s)是给定非线性函数.当g(s)=sn时(n 2为整数),由Fourier变换方法和绝对值估计,证明了对任意T>0,如果初始数据u0∈W3,1(R)∩H2(R),u1∈W1,1(R)∩L2(R),则Cauchy问题存在惟一的整体光滑解u∈C∞((0,T];H∞(R))∩C([0,T];H2(R))∩C1([0,T];L2(R)).利用凸性方法,证明了相应的Cauchy问题在空间C∞((0,T];H∞(R))∩C([0,T];H2(R))∩C1([0,T];L2(R))中不存在整体广义解.

源于非线性层晶格模型的一耦合Boussinesq型广义方程组的Cauchy问题

该文证明一源于非线性层晶格模型的耦合Boussinesq型方程组utt-a1uxx-a2uxxtt+a3(u-w)=f(ux)x,x∈R,t>0,(0.1)wtt-b1wxx-b2wxxtt+b3(w-u)=g(wx)x,x∈R,t>0(0.2)在C([0,∞);H^s(R)×H^s(R))(s≥2是一实数)中存在唯一的整体广义解,在C^2([0,∞);CB^2(R)×CB^2(R))(s>5/2)中存在唯一的整体古典解.对于Cauchy问题(0.1)-(0.2)解的爆破给出了充分条件.

广义Ostrovsky方程的Cauchy问题

利用Sobolev空间相应的知识以及一些不等式,研究有界区域内广义Ostrovsky方程解的存在性与唯一性问题,得到几个先验估计.通过应用Galerkin方法,证明在给定的初始条件下非线性强度为2的广义Ostrovsky方程存在唯一的整体解.

充分非线性Dullin-Gottwald-Holm方程的Cauchy问题

本文利用Sobolev不等式、算子半群理论和相关的偏微分方程的知识,分析和研究了充分非线性Dullin-Gottwald-Holm方程的性质。通过对该方程进行适当的变形,验证了该方程满足Kato理论的三个条件,并由此证明了该方程局部解的存在性、唯一性和解对初值的连续依赖性。

二维波动方程Cauchy问题广义解的适定性

建立了二维波动方程Cauchy问题在L2空间中的广义解,并证明了广义解在L2空间中的适定性.

弦振动方程Cauchy问题广义解的结构

建立了弦振动方程Cauchy问题在L2空间中的广义解,并证明了广义解在L2空间中与古典解具有相同的结构.