KdV方程纯孤立子解的整体渐近性质

研究KdV方程纯孤立子解的整体渐近性质,证明了N-孤立子解一致收敛到N个单孤立子解的叠加.进而得到了N-孤立子解在L1-范数意义下的渐近结果,并借此阐述了纯孤立子解与一般速降解的差异.     

Camassa-Holm方程凹凸尖峰及光滑孤立子解

研究一类完全可积的新型浅水波方程Camassa-Holm方程的行波孤立子解及双孤立子解.引入凹凸尖峰孤立子及光滑孤立子的概念,研究得到该方程的行波解中具有尖峰性质的凹凸尖峰孤立子解及光滑孤立子解.同时利用Backlund变换给出该类方程的新的双孤立子解.     

具结构阻尼的拟线性膜方程的吸引子及其上半连续性

本文研究具结构阻尼的拟线性膜方程utt+Δ²u+(-Δ)^αut+Δφ(Δu)+f(u)=g的适定性以及解的长时间动力学行为,其中α∈(1,2),旨在研究耗散指标α对方程解的适定性和长时间动力学行为的影响.本文证明非线性项φ(s)存在一个依赖于耗散指标α的临界指数pα=(N+4(α-1))/(N-4(α-1))⁺(N=3,4),当1≤pα时,对f(u)没有任何多项式增长限制:(ⅰ)方程的初边值问题是适定的,其解当t> 0时具有整体正则性;(ⅱ)对任意α∈(1,2),对应的解算子半群S^α(t)在自然能量空间中存在整体吸引子和指数吸引子;(ⅲ)整体吸引子族{Aα}在任意点α0∈(1,2)处上半连续,即对Aα0。的任意邻域U,当|α-α0|<<1时有Aα■U.     

(2+1)-维变系数CDGKS方程的Bcklund变换及Gramm-type Pfaffian解

孤立子在非线性的流体力学、等离子物理学、光学、生物学等领域有广泛的应用.将(2+1)维常系数CDGKS方程扩展为(2+1)维变系数CDGKS方程,利用双线性方法求出了该方程的Bcklund变换,进一步求出变系数CDGKS方程及其修正变系数CDGKS方程的Gramm-type Pfaffian解,从而解决了变系数孤立子方程的精确解.     

(3+1)维Potential-Yu-Toda-Sasa-Fukuyama方程新的多周期孤子解

该文利用Hirota双线性形式和广义三波测试法构建了(3+1)维Potential-Yu-TodaSasa-Fukuyama方程新的多周期孤子解.其中有一些完全新的周期孤子解,包括周期性交叉扭结波解、周期性双孤立波解和呼吸型双孤立波解.借助于符号计算,呼吸子和孤子的相互作用及传播特点被一些图形展示出来.     

非线性Schrdinger方程孤立子解的一般稳定性理论

自从Garduer,C.S.,Greem,J.M.,Kruskal M.D.和Miura,R,M,用反散射方法(ISM)求解KdV方程u_t—6uu_x u_(xxx)=0而获得孤立子解的论文发表以来[1],由于孤立子的概念以及所提供的研究方法在数学、物理,特别在近代物理(如等离子体物理,固体物理等)中的应用日广而得到较大地发展。近代物理实验和理论研究中一个颇为人们关注的问题是在一定意义的扰动下孤立子解的稳定性[11]。     

U(1)场中CP~1模型任意涡旋状孤立子解的存在性及渐近估计

对U(1)场中含有Chern-Simons项的CP~1模型用变分法证明了其拓扑孤立子解的存在性.进而,又用分析的方法讨论了该解的单调性和渐近性.     

Degasperis-Procesi方程的类孤子新解

利用辅助方程与函数变换相结合的方法,构造了Degasperis-Procesi(D-P)方程的无穷序列类孤子新解.首先,通过两种函数变换,把D-P方程化为常微分方程组.然后,利用常微分方程组的首次积分,把D-P方程的求解问题化为几种常微分方程的求解问题.最后,利用几种常微分方程的Bcklund变换等相关结论,构造了D-P方程的无穷序列类孤子新解.这里包括由Riemannθ函数、Jacobi椭圆函数、双曲函数、三角函数和有理函数组成的无穷序列光滑孤立子解、尖峰孤立子解和紧孤立子解.     

一类非线性算子方程的正算子解的研究

研究了算子方程X^(-1)+A(-1)+A⁺X+X^tA=Q,的正算子解问题,给出了此类非线性算子方程正算子解的范围以及正算子解存在的一些充分必要条件,并用迭代的方法得到了方程的正算子解.     

非手征对称的共形可积Toda场的孤立子解

用Hirota方法给出了左右不对称的共形可积Toda场的单孤立子解和双孤立子解.     

A simple but efficient approach for studying on nonlinear differential-difference equations

In this paper, we present a new approach for constructing exact solutions to nonlinear differential-difference equations (NLDDEs). By applying the new method, we have studied the saturable discrete nonlinear Schrodinger equation (SDNLSE) and obtained a number of new exact localized solutions, including discrete bright soliton solution, dark soliton solution, bright and dark soliton solution, alternating phase bright soliton solution, alternating phase dark soliton solution and alternating phase bright and dark soliton solution, provided that a special relation is bound on the coefficients of the equation among the solutions obtained.     

(2+1)维AKNS方程的行波解研究(英文)

Based on the travelling wave method, a(2 + 1)-dimensional AKNS equation is considered. Elliptic solution and soliton solution are presented and it is shown that the soliton solution can be reduced from the elliptic solution. It also proves that the result is consistent with the soliton solution of simplify Hirota bilinear method by Wazwaz and illustrate the solution are right travelling wave solution.     

Solving soliton equations with self-consistent sources by method of variation of parameters

Starting from the solutions of soliton equations and corresponding eigenfunctions obtained by Darboux transformation, we present a new method to solve soliton equations with self-consistent sources (SESCS) based on method of variation of parameters. The KdV equation with self-consistent sources (KdVSCS) is used as a model to illustrate this new method. In addition, we apply this method to construct some new solutions of the derivative nonlinear Schrödinger equation with self-consistent sources (DNLSSCS) such as phase solution, dark soliton solution, bright soliton solution and breather-type solution.     

Soliton versus the gas: Fredholm determinants,analysis, and the rapid oscillations behind the kinetic equation

We analyse the case of a dense modified Korteweg–de Vries (mKdV) soliton gas and its large time behaviour in the presence of a single trial soliton. We show that the solution can be expressed in terms of Fredholm determinants as well as in terms of a Riemann–Hilbert problem. We then show that the solution can be decomposed as the sum of the background gas solution (a modulated elliptic wave), plus a soliton solution: the individual expressions are however quite convoluted due to the interaction dynamics. Additionally, we are able to derive the local phase shift of the gas after the passage of the soliton, and we can trace the location of the soliton peak as the dynamics evolves. Finally, we show that the soliton peak, while interacting with the soliton gas, has an oscillatory velocity whose leading order average value satisfies the kinetic velocity equation analogous to the one posited by V. Zakharov and G. El.     

(3+1)维时间分数阶KdV-Zakharov-Kuznetsov方程的分支分析及其行波解

首先,运用拟设方法和动力系统分支方法,获得了(3+1)维时间分数阶KdV-Zakharov-Kuznetsov方程的奇异孤子解、 亮孤子解、 拓扑孤子解、 周期爆破波解、 孤立波解等.再利用MAPLE软件画出了KdV-Zakharov-Kuznetsov方程在不同条件下的分支相图.最后,讨论了行波解之间的联系.     

Solitons, chaos and fractals in the (2 + 1)-dimensional dispersive long wave equation

For a higher-dimensional integrable nonlinear dynamical system, there are abundant coherent soliton excitations. With the aid of a projective Riccati equation approach, the paper obtains several types of exact solutions to the (2 + 1)-dimensional dispersive long wave (DLW) equation which include multiple soliton solution, periodic soliton solution and Weierstrass function solution. Subsequently, several multisolitons are derived and some novel features are revealed by introducing lower-dimensional patterns.     

The families of explicit solutions for the Hirota equation

The well‐known shallow wave equation can be reduced to the Hirota equation with the aid of corresponding transformation. We discuss its explicit solutions, including dark soliton solution, multiple soliton solution, multiple singular solution, and periodic solutions.     

Dynamics of solitons in plasmas for the complex KdV equation with power law nonlinearity

This paper obtains the 1-soliton solution of the complex KdV equation with power law nonlinearity. The solitary wave ansatz is used to carry out the integration. The soliton perturbation theory for this equation is developed and the soliton cooling is observed for bright solitons. Finally, the dark soliton solution is also obtained for this equation.     

Higher-Order Solitons in the N-Wave System

The soliton dressing matrices for the higher-order zeros of the Riemann–Hilbert problem for the N -wave system are considered. For the elementary higher-order zero, that is, whose algebraic multiplicity is arbitrary but the geometric multiplicity is 1, the general soliton dressing matrix is derived. The theory is applied to the study of higher-order soliton solutions in the three-wave interaction model. The simplest higher-order soliton solution is presented. In the generic case, this solution describes the breakup of a higher-order pumping wave into two higher-order elementary waves, and the reverse process. In non-generic cases, this solution could describe (i) the merger of a pumping sech wave and an elementary sech wave into two elementary waves (one sech and the other one higher order); (ii) the breakup of a higher-order pumping wave into two elementary sech waves and one pumping sech wave; and the reverse processes. This solution could also reproduce fundamental soliton solutions as a special case.