MKdV方程的反散射解

本文考虑修正KdV(MKdV)方程u_t+6u~2u_x+u_(xxx)=0的反散射解,给出当反射系数为零且特征根为纯虚数时解的简洁表达式,并讨论了单孤子解和双孤子解。     

带非均匀项的Sine—Gordon方程

文中得出了x-SG方程(1)的B(?)cklund变换和反散射形式。通过方程(1)的反散射解研究,我们得到了当特征问题(2.4)的位势u(x,t)(q(x,t)=-1/2 u_x(x,t))满足方程(1)时的散射量随时间的演化规律,并分别利用B(?)cklund变换和反散射方法,我们求出了方程(1)的孤子解,且它们是一致的。     

一类带有非均匀项的广义KdV方程的孤波解

一类带有非均匀项的广义ＫｄＶ方程的孤波解朱佐农（扬州大学农学院基础部，扬州２２５Ｏ０１）－、引言众所周知，ＫｄＶ方程已被广泛研究［１］．从方程（１）的高阶守恒量出发，Ｌａｘ得到第一族高阶ＫｄＶ方程，其５阶形式为：从（２）的守恒量出发，Ｓａｗａｄａ和Ｋ...     

含和不含外力项的KdV和MKdV方程的求解公式及各种类型的解

本文研究KdV和MKdV方程,其特点在于构造变系数非线性非齐次的偏微分方程及其求解公式,由于其系数是通用型的,故可通过变系数的适当选择,从中找到KdV和MKdV方程及其解,其实质是通过一个泛函把三阶的KdV和MKdV方程转变成4个任意函数的二阶方程来处理。本文获得了变系数KdV和MKdV方程及其孤立子解及含外力项的KdV和MKdV方程及其精确解。     

组合KdT与MKdV方程的显式精确解

本文通过直接代数方法与假设方法的一种结合,求出了组合ＫｄＶ和ＭＫｄＶ方程的一些显式精确行波解。     

带非均匀项sine-Gordon方程的Bcklund变换及对易定理

Bcklund变换(BT)的对易定理是一个很重要的性质,但其数学证明在文献中讨论得较少。文[1]给出了一类保谱的MKdv-SG方程的BT及对易定理的证明.本文研究非保谱的带非均匀项的sine-Gordon方程u_(xt)=sinu (axu_x)_x,(a为参数),(1)它的特征值满足关系λ_1=αλ。我们给出了方程(1)的BT,并证明了对易定理.     

MKdV方程的两组对称及其几何意义

本文给出MKdV方程的两组新的对称及其几何解释。     

非均匀介质中波动方程的部分不变解

讨论了来自于非均匀介质中波动方程的部分不变解的存在性，证明了在波速满足适当的条件下部分不变解是存在的，并得到了部分不变解。     

耗散MKdV方程的指数吸引子

讨论了无界区域R~1上的MKdV方程,运用带权空间构造一类紧算子和算子分解的方法,得到该方程在H~2（R~1）上指数吸引子的存在性.     

An Invariant Group of MKdV Equation

In this paper, we present an invariant group of the MKdV equation q_t = q_{xxx} - 6q²q_x. By using this invariant group, we can obtain some new solutions from a known solution by quadrature.     

A Riemann-Hilbert Approach to the Harry-Dym Equation on the Line

In this paper, the authors consider the Harry-Dym equation on the line with decaying initial value. They construct the solution of the Harry-Dym equation via the solution of a 2 × 2 matrix Riemann-Hilbert problem in the complex plane. Further, onecusp soliton solution is expressed in terms of the Riemann-Hilbert problem.     

N-soliton solution of a lattice equation related to the discrete MKdV equation

We present an N-soliton solution of a lattice equation related to the discrete MKdV equation under an arbitrary boundary value at infinity.     

A new periodic solution to Jacobi elliptic functions of MKdV equation and BBM equation

Based on the homogeneous balance method,the Jacobi elliptic expansion method and the auxiliary equation method,the first elliptic function equation is used to get a new kind of solutions of nonlinear evolution equations.New exact solutions to the Jacobi elliptic function of MKdV equations and Benjamin-Bona-Mahoney (BBM) equations are obtained with the aid of computer algebraic system Maple.The method is also valid for other (1+1)-dimensional and higher dimensional systems.     

Symmetry reductions and soliton-like solutions for the variable coefficient MKdV equations

Two types of symmetry reductions are derived for the variable coefficient MKdV equation, which contain well-known Painleve II type equation and Jacobian elliptic equation. In addition, soliton-like solutions of the variable coefficient MKdV equation are also obtained. Finally, a transformation between the variable coefficient MKdV equation and the MKdV equation are also found.     

五阶势MKdV方程的一个不变性

§1Introduction Asweknow,Backlundtransformation[1-3]isaverypowerfulwayforfindingnonline evolutionequations.Inrecentdecades,Painlevéanalysis[4]hasbecomeaverypopu methodtoobtainBacklundtransformation.Inreference[5],fordevelopingthetheory Painlevéanalysis,AndrewPickeringintroduceanewexpansionvariableZwhichsatisf thefollowingRicattiSystem:Zx=1-AZ-BZ2,Zt=-C+(AC+Cx)Z-(D-BC)Z2.(1.Astheapplicationofthenewexpansionvaraible,thepotentialfifth-orderMKd equation(PMKdV5)-vxt+(vxxxxx-10k2v2…     

LAX REPRESENTATIONS FOR DIRAC SOLITON HIERARCHY

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The Cauchy Problem of the Porous Medium Equation with Absorption

In this paper we study the existence of solution for the following Cauchy problem {u_t = Δu^m - u^p u(x,0) = u_0(x) We show how the growth condition of initial trace is determined by the absorption.