二阶线性时滞微分方程的广义振动性

本文主要研究了二阶线性时滞微分方程的广义振动性和广义非振动性,给出了方程广义振动和广义非振动的一些判定定理,同时给出了一类方程广义非振动的充要条件.     

二阶中立型差分方程的振动性

研究了一类变系数的二阶中立型时滞差分方程的振动性,得到了该类方程振动及解的一阶差分振动的充分条件。     

一类具多滞量的二阶中立型差分方程的振动定理

研究了一类具有多个滞量的变系数的二阶中立型差分方程的振动性,给出了该类方程振动及差分算子振动的充分条件。     

负系数差分方程的振动性质

研究了一类负系数差分方程的振动性质,得到了这类差分方程振动的判据.     

一阶中立型时滞差分方程的线性化振动性定理

本文考虑一类非线性中立型时滞差分方程,证明了在一定条件下,若与此方程相关的一个线性差分方程的每个解振动,则该非线性差分方程的每个解也振动。     

一类非线性延迟微分方程数值解的振动性分析

本文考虑一类非线性延迟微分方程-带有单峰造血率的造血模型数值解的振动性及非振动性。运用线性化理论,把非线性差分方程的振动性转化为其对应的线性差分方程的振动性,通过判断线性方程的特征方程根的情况,得到了非线性差分方程振动和存在非振动解的充分条件。对于非振动的数值解,证明了非振动的数值解最终都趋于方程的平衡解。为了更有力的说明我们的结果给出了相应的算例.     

具有可变时滞的非线性非自治差分方程的振动性及其应用

本文获得了一类具有可变时滞的非线性非自治差分方程的振动准则,建立了这类差分方程的几个线性化振动性定理,并得到了具有可变时滞的离散型非自治广义Logistic方程关于其正平衡点振动的一系列充分条件.     

具连续变量的二阶非线性差分方程振动和非振动的充要条件

研究了一类具有连续变量的二阶非线性差分方程的振动性质,利用Banach空间的不动点原理和一些分析技巧,得到了这类方程存在非振动解的充分必要条件,并得到了这类方程振动的充分必要条件,同时给出了说明定理应用的例子.     

一类二阶非线性中立型差分方程的振动性

研究了二阶非线性中立型差分方程Δ2(xn+pxn-l)+qnf(xn-k)=0的振动性,获得了该类方程振动的三个充分性定理.所得结果将一阶非线性中立型差分方程已有振动性的相应结论推广到了二阶非线性中立型差分方程.     

具连续变量的非线性时滞差分方程的振动性

本文研究了一类具有连续变量的非线性时滞差分方程的振动性,给出了该类方程振动的几个充分条件。     

Inverse scattering transformation and soliton stability for a nonlinear Gross–Pitaevskii equation with external potentials

We consider the Gross–Pitaevskii(GP) equation with the combination of periodic and harmonic external potentials. In particular, the method of inverse scattering transformation is applied to the GP equation with external potentials. Furthermore, some exact soliton solutions are obtained for the GP equation by using inverse scattering transformation, in which some physically relevant bright solutions are described. The stabilities of the obtained matter-wave solutions are addressed numerically such that some stable solutions are found, and some solitons can be stable in a wide region. These results may raise the possibility of relative experiments and potential applications.     

关于算子方程Nχ=δLχ解的若干研究

利用多重拓扑度的性质以及一些不等式研究了零指标的Predholm算子和L-全连续算子方程Nχ=δχ的解,获得若干新的结果,推广了一些重要结论,并将结果应用到一类二阶微分方程的边值问题中.     

一类弱耗散Camassa-Holm 方程Cauchy问题在Besov 空间解的局部适定性

利用Littlewood-Paley 理论和输运方程解的先验估计, 在Besov 空间 中证明了一类弱耗散Camassa-Holm 方程Cauchy 问题解的局部适定性, 同时给出了解的能量估计及爆破准则.     

New periodic wave and soliton solutions for a Kadomtsev–Petviashvili (KP) like equation coupled to a Schrödinger equation

The periodic wave solutions for Kadomtsev–Petviashvili (KP) like equation coupled to a Schrödinger equation are obtained by using of Jacobi elliptic function method, in the limit cases, the multiple soliton solutions are also obtained. The properties of some periodic and soliton solution for this system are shown by some figures.     

THE GLOBAL DUFORT-FRANKEL DIFFERENCE APPROXIMATION FOR NONLINEAR REACTION-DIFFUSION EQUATIONS

1.IntroductionInthispaperweconsiderthefollowinginitial-valueproblemofnonlinearreactiondiffusionequation:HerefiisaboundeddomaininRd(d<3)withaLipschitzboundaryOffand7isapositiveconstallt.Lettheset{in*l:j(u*)=0}benotemptyandu=ma-c{lu*I:f(u*)=0}.Assumptionont…     

COLE-HOPF QUOTIENT AND EXACT SOLUTIONS OF THE GENERALIZED FITZHUGH-NAGUMO EQUATIONS

1IntroductionTheFitzhugfh-Nagullloequatioll'at=AL.r.r '(L('u--a)(1--'u)(1.1jisallimportantllolllinearreactioll-diffusiollequation.Itisusedwidelyillcircuittheory,I)l()I()gy(llldoillerfields.Thisequationhasobviouslythreetrivialsolutiolls:it=0,a.1.Bysotzt,illgIc=f(x--ct),onecallobtaillitsthreeheteroclinicsohltions.Inordertofill'litslllor(}axal('t~sollltiolls.someInethodswhicllareoillyllseftllforilltegrablesystellis11ave})chillgclleri\lizc(\Itotillsuoniutegrableequation.K;twaharaandTal,aka[1…     

非线性发展方程新的显式精确解

借助Ｍａｔｈｅｍａｔｉｃａ系统,采用三角函数法和吴文俊消元法,本文获得了著名的２＋１维ＫＰ方程的若干精确解,其中包括新的精确解和孤波解．在此基础上,进而得到著名ＫｄＶ方程、Ｈｉｒｏｔａ－Ｓａｔｓｕｍａ方程和耦合ＫｄＶ方程的一些精确解．     

Irreducibility and strong Feller property for non-linear SPDEs

Under some non-degeneracy condition, the strong Feller property and irreducibility are studied for non-linear stochastic partial differential equations driven by multiplicative noise within the framework called ‘variational approach’. Our result for irreducibility can be applied to equations with locally monotone coefficients. In some special cases, we discuss the Hölder continuity of the associated Markov semigroups. The main results are applied to several examples such as stochastic Burgers equation, stochastic porous media equation and stochastic fast diffusion equation.     

OSCILLATION FOR NONLINEAR SECOND-ORDER DYNAMIC EQUATIONS ON TIME SCALES

Through the use of generalized Riccati transformation techniques, we establish some oscillation criteria for one type of nonlinear dynamic equation on time scales. Several examples, including a semilinear dynamic equation and a nonlinear Emden-Fowler dynamic equation, are also given to illustrate these criteria and to improve the results obtained in some references.     

几种微分方程李对称决定组生成软件包的比较研究

根据微分方程李对称决定方程组生成算法,在计算机代数系统Maple上给出了具体实现GDS,并指出了现行Maple系统上关于李对称计算的软件包liesymm的缺陷,最后通过一些计算实例对三个Maple系统下的软件包GDS,liesymm以及Desolv进行了比较研究.