极化电场对可激发介质中螺旋波的控制

螺旋波在不同的物理、化学和生物系统中普遍存在.周期外场,比如极化电场,尤其是具有旋转对称性的圆极化电场可对螺旋波动力学产生重要影响.本文综述了极化电场对可激发介质中螺旋波的控制,包括共振漂移、同步、手征对称性破缺、多臂螺旋波的稳定、次激发介质中的螺旋波、三维回卷波湍流态的控制、心脏组织中螺旋波的去钉扎、心脏组织中螺旋波湍流态的控制等.     

非线性单摆的Jacobi椭圆函数解

对非线性单摆运动进行了数值分析,用Matlab绘出其运动相图,并求出了它在一定条件下的Jacobi椭圆函数解.     

A new expansion method of first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term and its application to mBBM model

Based on a first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term which is extended from a type of elliptic equation, and by converting it into a new expansion form, this paper proposes a new algebraic method to construct exact solutions for nonlinear evolution equations. Being concise and straightforward, the method is applied to modified Benjamin-Bona-Mahony （mBBM） model, and some new exact solutions to the system are obtained. The algorithm is of important significance in exploring exact solutions for other nonlinear evolution equations.     

组合KdV-mKdV方程的Jacobi椭圆函数解

对第一类椭圆方程进行新形式的函数展开，构造出非线性波动方程新的Jacobi椭圆函数解.将该方法应用于组合KdV-mKdV方程，得到方程新的Jacobi椭圆函数解，并列出一些具体的解和作出相应的图形.     

Interactions between defects and propagating hydrodynamic solitons

<正>This paper studies the hydrodynamic solitons propagating along a long trough with a defective bed.The slight deviation from the plane in the bed serves as the depth defects.Based on the perturbation method,it finds that the free surface wave is governed by a Korteweg-de Vries(KdV) equation with a defect term(KdVD).The numerical calculations show that,for a single-convexity localized defect,the propagating soliton is decelerated as it comes into the defect region,and it is accelerated back to its initial velocity as it leaves,which has a dipole effect.As a result, its displacement is lagged in contrast to the uninfluenced one.And an up-step defect makes the propagating soliton decelerate simply.The opposite influence will occur for a single-concavity localized defect and a down-step one.The defect-induced influence on propagating hydrodynamic solitons depends on the polarity of defects,which agrees with that on non-propagating ones.However,the involved dipole effect of the single localized defect is not displayed in non-propagating cases.