耦合Burgers方程的Painleve分析和相关性质

为研究耦合Burgers方程的可积性，利用WTC测试方法，给出了第一类Burgers方程的Painleve性质和第二类Burgers方程的条件Painleve性质．进而得到了第一类方程的变量分离解和第二类方程的（N2＋3N＋6/2）-参数Lie点对称群．     

耦合Burgers方程的Painleve分析和相关性质

为研究耦合Burgers方程的可积性,利用WTC测试方法,给出了第一类Burgers方程的Painleve性质和第二类Burgers方程的条件Painleve性质．进而得到了第一类方程的变量分离解和第二类方程的（N2＋3N＋6/2）-参数Lie点对称群．     

指数同伦法对Cauchy条件下变系数Burgers方程的解析与数值分析

使用近似解析法来研究在给定初始条件和边界条件下变系数Burgers方程,引入一种新式同伦来解决微分方程中由变系数带来的问题,这种新同伦比传统方法计算更高效,并能给出时域上的一致解析表达式.分别计算了有限空间域上变系数Burgers方程的解析解,讨论了在有限空间区域上激波的形成,并对所得解析解进行了范数意义下收敛性研究的探索.基于Lie(李)变换群理论,研究了该方程的对称性质,给出了其无穷小生成子,守恒律和群不变解.文中给出的解是从非线性偏微分方程中直接得到的,未经过行波变换.通过"h-curve"准则探讨了近似解的收敛性.通过有限差分法进行直接数值模拟,已验证该方法的准确性和有效性.     

一类CL方程的可逆变换,等价和准确解

本文给出了一类CL(守恒律)方程的可逆变量变换,借助这种变换表明一类CL方程是准确可解的,这类方程等价于线性方程,Burgers方程(包括高阶Burgers方程)或者KdV方程(包括mKdV方程),并求出了几个CL方程的准确解.     

Burgers方程的一类交替分组方法

对于Burgers方程给出了一组新的Saul'yev型非对称差分格式，并用这些差分格式构造了求解非线性Burgers方程的交替分组四点方法．该算法把剖分节点分成若干组，在每组上构造能够独立求解的差分方程．因此算法具有并行本性，能直接在并行计算机上使用．章还证明了所给算法线性绝对稳定．数值试验表明，该方法使用简便，稳定性好，有很好的精度。     

Burgers方程的混合元分析及其数值模拟

1．引言混合有限元法在高阶偏微分方程和含有两个战者两个以上）的未知国数的偏微分方程的数值解的研究中起着重要的作用．但是,到目前为止,混合有限元法主要是用于2n阶或一阶偏微分方程（组）,如二阶椭圆型方程、平面弹性力学方程、双调和方程、Stokes和Navier－stokes方程、抛物型方程以及电磁场方程修见＞到以及当中的参考文献）．然而,R前混合有限元法还没有被用于对非线性的Burgers方程作数值研究．而过去对Burgers方程的数值研究主要采用标准有限元法、差分方法和谱方法修见【IO－12］以及当中的参考文献）．本文的目的是用混…     

发展方程谱方法的显隐Runge-Kutta方法

针对非齐次两点边值问题,首先给出了结合谱方法解发展方程的显式四阶RungeKutta方法的有效实现形式,又通过待定系数法构造出显隐Runge-Kutta的三阶格式,证明其为L-稳定.随后给出显隐Runge-Kutta高阶方法的有效实现形式,用此格式计算了Burgers方程和Korteweg-de Vries (KdV)方程,并将计算结果与目前常用的时间离散方法进行了比较.数值结果表明这些方法的有效性及可行性.     

广义KdV—Burgers方程的势对称和不变解

用微分形式的吴方法讨论了广义KdV—Burgers方程不同系数情况下的势对称,并且利用这些对称求得了相应的不变解,这些解对进一步研究广义KdV—Burgers方程所描述的物理现象具有重要意义．     

非线性发展型方程的Legendre拟谱逼近

本文考虑非稳态Burgers方程的拟谱逼近，构造了一类Legendre拟谱计算格式并证明了其收敛性，数值结果显示了格式的有效性。     

Burgers方程的高阶紧致有限体积解法

本文研究Burgers方程高阶紧致有限体积方法.基于Hopf-Cole变换,非线性Burgers方程转化为线性热传导方程.继而利用四阶紧致有限体积方法,进行空间离散.时间离散采用四阶Runge-Kutta格式,然后利用Fourier分析方法,进行空间的误差分析和时间离散的稳定性分析.典型算例显示出本方法的高精度与良好的计算效果.     

The recursion operator method for generalized symmetries and Bäcklund transformations of the Burgers’ equations

In this paper, the generalized symmetries of the second-order Burgers’ equation are obtained through the symmetry transformation method. The Bäcklund transformations (BTs) of the two equations are constructed by the recursion operator method. Then, the infinite number of exact solutions to these equations are investigated in terms of the generalized symmetries and Bäcklund transformations. Furthermore, the Bäcklund transformations and conservation law of the general Burgers’ equations are discussed.     

On symmetry-preserving difference scheme to a generalized Benjamin equation and third-order Burgers equation

In this paper, an exposition of a method is presented for discretizing a generalized Benjamin equation and third-order Burgers equation while preserving their Lie point symmetries. By using local conservation laws, the potential systems of original equation are obtained, which can be used to construct the invariant difference models and symmetry-preserving difference models of original equation, respectively. Furthermore, this method is very effective and can be applied to discrete high-order nonlinear evolution equations.     

A non-variational approach to the construction of new ‘higher-order’ conservation laws of the family of nonlinear equations α(ut + 3uux) + β(utxx + 2uxuxx + uuxxx) − γuxxx = 0

In this paper, we study and classify the conservation laws of the combined nonlinear KdV, Camassa–Holm, Hunter–Saxton and the inviscid Burgers equation which arises in, inter alia, shallow water equations. It is shown that these can be obtained by variational methods but the main focus of the paper is the construction of the conservation laws as a consequence of the interplay between symmetry generators and ‘multipliers’, particularly, the higher-order ones.     

Nonautonomous first integrals and general solutions of the KdV‐Burgers and mKdV‐Burgers equations with the source

The method for constructing first integrals and general solutions of nonlinear ordinary differential equations is presented. The method is based on index accounting of the Fuchs indices, which appeared during the Painlevé test of a nonlinear differential equation. The Fuchs indices indicate us the leading members of the first integrals for the origin differential equation. Taking into account the values of the Fuchs indices, we can construct the auxiliary equation, which allows to look for the first integrals of nonlinear differential equations. The method is used to obtain the first integrals and general solutions of the KdV‐Burgers and the mKdV‐Burgers equations with a source. The nonautonomous first integrals in the polynomials form are found. The general solutions of these nonlinear differential equations under at some additional conditions on the parameters of differential equations are also obtained. Illustrations of some solutions of the KdV‐Burgers and the mKdV‐Burgers are given.     

A Legendre–Galerkin Chebyshev collocation method for the Burgers equation with a random perturbation on boundary condition

In the paper, we apply the generalized polynomial chaos expansion and spectral methods to the Burgers equation with a random perturbation on its left boundary condition. Firstly, the stochastic Galerkin method combined with the Legendre–Galerkin Chebyshev collocation scheme is adopted, which means that the original equation is transformed to the deterministic nonlinear equations by the stochastic Galerkin method and the Legendre–Galerkin Chebyshev collocation scheme is used to deal with the resulting nonlinear equations. Secondly, the stochastic Legendre–Galerkin Chebyshev collocation scheme is developed for solving the stochastic Burgers equation; that is, the stochastic Legendre–Galerkin method is used to discrete the random variable meanwhile the nonlinear term is interpolated through the Chebyshev–Gauss points. Then a set of deterministic linear equations can be obtained, which is in contrast to the other existing methods for the stochastic Burgers equation. The mean square convergence of the former method is analyzed. Numerical experiments are performed to show the effectiveness of our two methods. Both methods provide alternative approaches to deal with the stochastic differential equations with nonlinear terms.     

Integrability conditions for a certain class of nonlinear evolution equations and Kähler geometry

Multicomponent evolution equations associated with linear connections on complex manifolds are considered. It is proved that under some general assumptions an equation from this class is integrable by inverse scattering method if the corresponding linear connection is the Levi-Civita connection of an indefinite Kählerian metric of constant holomorphic sectional curvature. This result is based on a certain characterization of the above-mentioned Levi-Civita connections. It is shown that the obtained integrable equations are generalized ferromagnetics, and recurrent formulas for their local conservation laws are given.     

Stochastic control for a class of random evolution models

We construct the explicit connection existing between a solvable model of the discrete velocities non-linear Boltzmann equation and the Hamilton-Bellman-Jacobi equation associated with a simple optimal control of a piecewise deterministic process. This study extends the known relation that exists between the Burgers equation and a simple controlled diffusion problem. In both cases the resulting partial differential equations can be linearized via a logarithmic transformation and hence offer the possibility to solve physically relevant non-linear field models in full generality.     

A modified tanh–coth method for solving the KdV and the KdV–Burgers’ equations

In this work we use a modified tanh–coth method to solve the Korteweg-de Vries and Korteweg-de Vries–Burgers’ equations. The main idea is to take full advantage of the Riccati equation that the tanh-function satisfies. New multiple travelling wave solutions are obtained for the Korteweg-de Vries and Korteweg-de Vries–Burgers’ equations.     

Decay mode solution of nonlinear boundary–initial value problems for the cylindrical (spherical) Boussinesq–Burgers equations

The major target of this paper is to construct new nonlinear boundary–initial value problems for Boussinesq–Burgers Equations, and derive the solutions of these nonlinear boundary–initial value problems by the simplified homogeneous balance method. The nonlinear transformation and its inversion between the Boussinesq–Burgers Equations and the linear heat conduction equation are firstly derived; then a new nonlinear boundary–initial value problem for the Boussinesq–Burgers equations with variable damping on the half infinite straight line is put forward for the first time, and the solution of this nonlinear boundary–initial value problem is obtained, especially, the decay mode solution of nonlinear boundary–initial value problem for the cylindrical (spherical) Boussinesq–Burgers equations is obtained.     

A modified tanh–coth method for solving the general Burgers–Fisher and the Kuramoto–Sivashinsky equations

In this work we use a modified tanh–coth method to solve the general Burgers–Fisher and the Kuramoto–Sivashinsky equations. The main idea is to take full advantage of the Riccati equation that the tanh-function satisfies. New multiple travelling wave solutions are obtained for the general Burgers–Fisher and the Kuramoto–Sivashinsky equations.