New family of overturning soliton solutions for a typical breaking soliton equation

The breaking soliton equations are of current interest, while the application of computer algebra to sciences has a bright future. In this paper, a new family of overturning soliton solutions for a typical breaking soliton equation is obtained via a computer-algebra-based method. An example of explicit solutions from the family is given. Solitary waves are also shown to be merely a simple case belonging to the family.     

Solitons to rogue waves transition,lump solutions and interaction solutions for the (3+1)-dimensional generalized B-type Kadomtsev–Petviashvili equation in fluid dynamics

ABSTRACT

In this work, we investigate the (3+1)-dimensional generalized B-type Kadomtsev–Petviashvili (gBKP) equation in fluid dynamics, which plays an important role in depicting weakly dispersive waves propagated in a quasi-media and fluid mechanics. By employing Hirota's bilinear method, we derive the one- and two-soliton solutions of the equation. Moreover, we reduce those soliton solutions to the periodic line waves and exact breather waves by considering different parameters. A long wave limit is used to derive the rogue wave solutions. Based on the resulting bilinear representation, we introduce two types of special polynomial functions, which are employed to find the lump solutions and interaction solutions between lump and stripe soliton. It is hoped that our results can be used to enrich dynamic behaviours of the (3+1)-dimensional BKP-type equations.     

一般Hirota-Satsuma方程的多孤子解及孤子间的相互作用

用改进的齐次平衡法,首先把不可积的一般Hirota-Satsuma方程简化成可积模型—KdV方程,然后通过求解KdV方程得到了一般Hirota-Satsuma方程的多孤子解.利用得到的多孤子解分析了奇异孤子之间、钟型孤子与奇异孤子之间的相互作用,结果发现了相互作用的一些重要性质.     

对称在破裂孤立子方程中的应用

首先对带有积分项的破裂孤立子方程（breaking soliton equation）进行变换,然后利用待定系数法求出它的对称,通过验证知道原方程的李群能构成李代数,再利用优化系统对原方程进行约化,求出了原方程的一些新解。     

On closed form solutions of (2+1)-breaking soliton system by similarity transformations method

In the present research, similarity transformation method via Lie-group theory is proposed to seek some more exact closed form solutions of the (2+1)-dimensional breaking soliton system. The system describes the interactions of the Riemann wave along y-axis and long wave along x-axis. Some explicit solutions of breaking soliton system are attained with appropriate choices of the arbitrary functions and making use of arbitrary constants involved in the infinitesimals. In order to obtain physically meaningful solutions, numerical simulation is performed. On the basis of graphical representation, the physical analysis of solutions reveals into multi-solitons, periodic, quadratic, asymptotic and stationary profiles.     

电孤子信号用于超宽带通信发射脉冲的研究

介绍了孤子现象和非线性传输线路,分析了电孤子的产生和电孤子振荡器的原理。对Toda电路的电孤子脉冲信号及其导数函数在时域及频域做了理论推导分析,并在美国联邦通信委员会带宽和室内辐射功率限制下做了仿真验证。仿真结果表明,选择合适的参数和阶数能使电孤子振荡器产生的电孤子脉冲符合FCC要求,可用作超宽带通信发射脉冲。     

Integrability,soliton solutions and modulation instability analysis of a (2+1)-dimensional nonlinear Heisenberg ferromagnetic spin chain equation

We consider the Heisenberg ferromagnetic spin chain equation, which is governed by the (2+1)-dimensional nonlinear Schrödinger-type equation. Based on the Ablowitz–Kaup–Newell–Segur frame, we study the integrability of the equation by deriving its Lax pair and infinite conservation laws. By introducing a potential transformation, we obtain its Hirota bilinear form and soliton solutions. Based on the resulting lax pair, we construct Darboux transformation and multi-soliton solutions of the equation. Furthermore, we also find the other type of soliton solutions for the equation by considering its Bäcklund transformation. Finally, we discuss the linear stability analysis by considering its stability condition for the stationary solution of the equation, which can be used to analyze modulation instability. The technique presented in this work is analytical, which can be used to enrich the dynamical of the Heisenberg ferromagnetic spin chain equation.     

Analytic multi-soliton solutions of the generalized Burgers equation

The most elementary ansatz of the double-Exp-function method for finding exact double-wave solutions can be produced by an extension of a two-soliton ansatz in a fractional form. The generalized Burgers equation is used as an example, and closed form analytic multi-soliton solutions are obtained for the first time.     

Nonlinear stability,excitation and soliton solutions in electrified dispersive systems

A weakly nonlinear theory of wave propagation in two superposed dielectric fluids in the presence of a horizontal electric field is investigated in (2+1)-dimensions. The equation governing the evolution of the amplitude of the progressive waves is obtained in the form of a two-dimensional nonlinear Schrödinger equation. A three-wave resonant interaction for nonlinear excitations created from electrohydrodynamic capillary-gravity waves is observed to be possible in a dispersive medium with a self-focusing cubic nonlinearity. Under suitable conditions, the nonlinear envelope equations for the resonant interaction are derived by using multiple scales and inverse scattering methods, and an explicit three-wave soliton solution is discussed. Both the dynamic properties and the modulational instability of finite amplitude electrohydrodynamic wave are studied for the cubic nonlinear Schrödinger equation by means of linearized stability analysis and the nonlinear interaction coefficient. We show that the trajectories in phase space exhibit different behavior with the increase of nonlinear perturbations, and we determine the electric field and wavenumber ranges at which the original point is elliptic or hyperbolic, respectively. It is found also that the presence of the electric field in the equation modifies the nature of wave stability and soliton structures, and that the amplitude and width of the soliton are decreased and increased, respectively, when the electric field value increases.     

Some examples of inelastic soliton interaction

An analogue of the Boussinesq equation is presented which is exact for ion-sound (s) waves in the linear limit and which is correct in the sense of the Cauchy problem. This equation can be used to study by computer the dynamics of various wave processes when weak nonlinearities and dispersive effects are taken into account. An equation is obtained to describe the hydrodynamic velocity of small amplitude s-waves. Properties of solitons and processes of their formation are investigated analytically and by computer. It is demonstrated that soliton interactions described by these equations are inelastic and that the coefficient of inelasticity increases with an increase of amplitude of the interacting solitons.     

Interaction solutions of a (2+1)-dimensional dispersive long wave system

With the help of the consistent $tanh$ expansion, this paper obtains the interaction solutions between solitons and potential Burgers waves of a (2$+$1)-dimensional dispersive long wave system. Based on some known solutions of the potential Burgers equation, the multiple resonant soliton wave solutions, soliton–error function wave solutions, soliton–rational function wave solutions and soliton–periodic wave solutions are obtained directly.     

The N-soliton solution and localized wave interaction solutions of the (2+1)-dimensional generalized Hirota-Satsuma-Ito equation

In this paper, the $N$-soliton solution is constructed for the ($2+1$)-dimensional generalized Hirota–Satsuma–Ito equation, from which some localized waves such as line solitons, lumps, periodic solitons and their interactions are obtained by choosing special parameters. Especially, by selecting appropriate parameters on the multi-soliton solutions, the two soliton can reduce to a periodic soliton or a lump soliton, the three soliton can reduce to the elastic interaction solution between a line soliton and a periodic soliton or the elastic interaction between a line soliton and a lump soliton, while the four soliton can reduce to elastic interaction solutions among two line solitons and a periodic soliton or the elastic interaction ones between two periodic solitons. Detailed behaviours of such solutions are illustrated analytically and graphically by analysing the influence of parameters. Finally, an inelastic interaction solution between a lump soliton and a line soliton is constructed via the ansatz method, and the relevant interaction and propagation characteristics are discussed graphically. The results obtained in this paper may be helpful for understanding the interaction phenomena of localized nonlinear waves in two-dimensional nonlinear wave equations.     

Rational solutions and their interaction solutions of the (2+1)-dimensional modified dispersive water wave equation

A bilinear form for the modified dispersive water wave (mDWW) equation is presented by the truncated Painlevé series, which does not lead to lump solutions. In order to get lump solutions, a pair of quartic–linear forms for the mDWW equation is constructed by selecting a suitable seed solution of the mDWW equation in the truncated Painlevé series. Rational solutions are then computed by searching for positive quadratic function solutions. A regular nonsingular rational solution can describe a lump in this model. By combining quadratic functions with exponential functions, some novel interaction solutions are founded, including interaction solutions between a lump and a one-kink soliton, a bi-lump and a one-stripe soliton, and a bi-lump and a two-stripe soliton. Concrete lumps and their interaction solutions are illustrated by 3d-plots and contour plots.     

含外力项时变系数KdV方程与时变系数耦合KdV方程组的孤子解

应用孤子拟解法研究了含外力项时变系数KdV方程与一类时变系数耦合KdV方程组.首先将方程经过变量代换转换为齐次方程,然后将孤子解假设为双曲正割函数的形式带入方程或方程组,最后借助Maple软件完成复杂的计算来确定假设的孤子解的待定系数,从而得到孤子解存在的条件及其孤子解.结果显示:孤子拟解法计算简便且能得到方程的亮孤子解.     

The influence of higher-order effects on the transmission performances of the ultra-short soliton pulses and its suppression method

Under the condition of the higher order effects, a propagation equation is established to investigate the way to suppress the soliton self frequency shift and timing jitter in the picosecond and femtosecond soliton communication system using a combined control method of time domain and frequency domain. By the use of the variational approach, the evolution of the chirping Gaussian quasi-soliton pulse is analyzed in the presence of the effects including third order dispersion, intrapulse Raman scattering (IR...     

Optical soliton perturbation with nonlinear damping and saturable amplifiers

The method of multiple-scale perturbation method is developed in a new way to study the propagation of optical solitons through a fiber governed by the perturbed nonlinear Schrödinger’s equation. We show that by newly introducing a proper definition of the phase of the soliton for the first time, one can obtain the correction to the pulse at the higher order. Also, numerical simulations support the analytical argument.     

Exact solutions of discrete complex cubic Ginzburg–Landau equation via extended tanh-function approach

In this paper, we obtained rich solutions for the discrete complex cubic Ginzburg–Landau equation by means of the extended tanh-function approach. These solutions include chirpless bright soliton, chirpless dark soliton, triangular function solutions and some solutions with alternating phases, and so on. Meanwhile, the range of parameters where some exact solution exists is given.     

Multi-symplectic integration of coupled non-linear Schrödinger system with soliton solutions

Systems of coupled non-linear Schrödinger equations with soliton solutions are integrated using the six-point scheme which is equivalent to the multi-symplectic Preissman scheme. The numerical dispersion relations are studied for the linearized equation. Numerical results for elastic and inelastic soliton collisions are presented. Numerical experiments confirm the excellent conservation of energy, momentum and norm in long-term computations and their relations to the qualitative behaviour of the soliton solutions.     

A Maple package for verifying ultradiscrete soliton solutions

We present a computer algebra program for verifying soliton solutions of ultradiscrete equations in which both dependent and independent variables take discrete values. The package is applicable to equations and solutions that include the max function. The program is implemented using Maple software.

Program summary

Program title: UltdeCatalogue identifier: AEDB_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDB_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 3171No. of bytes in distributed program, including test data, etc.: 13 633Distribution format: tar.gzProgramming language: Maple 10Computer: PC/AT compatible machineOperating system: Windows 2000, Windows XPRAM: Depends on the problem; minimum about 1 GBWord size: 32 bitsClassification: 5Nature of problem: The existence of multi-soliton solutions strongly suggest the integrability of nonlinear evolution equations. However enormous calculation is required to verify multi-soliton solutions of ultradiscrete equations. The use of computer algebra can be helpful in such calculations.Solution method: Simplification by using the properties of max-plus algebra.Restrictions: The program can only handle single ultradiscrete equations.Running time: Depends on the complexity of the equation and solution. For the examples included in the distribution the run times are as follows. (Core 2 Duo 3 GHz, Windows XP)

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Example 1: 2725 sec.

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Example 2: 33 sec.

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Example 3: 1 sec.