(2+1)维非线性薛定谔方程的环孤子,dromion,呼吸子和瞬子

利用分离变量法,研究了(2+1)维非线性薛定谔(NLS)方程的局域结构.由于在B?cklund变换和变量分离步骤中引入了作为种子解的任意函数,得到了NLS方程丰富的局域结构.合适地选择任意函数,局域解可以是dromion,环孤子,呼吸子和瞬子.dromion解不仅可以存在于直线孤子的交叉点上,也可以存在于曲线孤子的最近邻点上.呼吸子在幅度和形状上都进行了呼吸 关键词： 非线性薛定谔方程 分离变量法 孤子结构     

四阶非线性薛定谔方程中呼吸子解的特性研究

基于同时包含四阶色散项和四阶非线性项的非线性薛定谔层级结构的四阶可积方程(LPD方程),首先利用达布变换法得到LPD方程的单呼吸子解,并对呼吸子的动力学特性进行研究,得到呼吸子与W型孤子、抖动的W型孤子和周期波的转换关系;其次,借助达布变换的递推关系得到LPD方程的双呼吸子解,并利用呼吸子与孤子之间的转换关系,研究呼吸子与孤子以及呼吸子与周期波的碰撞特性;最后,对双呼吸子的碰撞特性进行更为详细的研究,得到双呼吸子的交叉碰撞、平行叠加及双呼吸子的简并态等动力学特性。     

一个新(2+1)维非线性演化方程的相干孤子结构

用分离变量法研究了新(2+1)维非线性演化方程的相干孤子结构.由于Bcklund变换和变量分离步骤中引入了作为种子解的任意函数,得到了新(2+1)维非线性演化方程丰富的孤子解.合适地选择任意函数,孤子解可以是solitoffs,dromions,dromion格子,呼吸子和瞬子.呼吸子不仅在幅度、形状,各峰间距离,甚至在峰的数目上都进行了呼吸. 关键词： 新(2+1)维非线性演化方程 分离变量法 孤子结构     

(1+1)维广义的浅水波方程的变量分离解和孤子激发模式

研究(1+1)维广义的浅水波方程的变量分离解和孤子激发模式. 该方程包括两种完全可积(IST可积)的特殊情况，分别为AKNS方程和Hirota-Satsuma方程. 首先把基于Bcklund变换的变量分离(BT-VS)方法推广到该方程，得到了含有低维任意函数的变量分离解. 对于可积的情况，含有一个空间任意函数和一个时间任意函数，而对于不可积的情况，仅含有一个时间任意函数，其空间函数需要满足附加条件. 另外，对于得到的(1+1)维普适公式，选取合适的函数，构造了丰富的孤子激发模式，包括单孤子，正-反孤子，孤子膨胀，类呼吸子，类瞬子等等. 最后，对BT-VS方法作一些讨论. 关键词： 浅水波方程 Bcklund变换 变量分离 孤子     

向列相液晶中强非局域空间光孤子传输的理论研究

对向列相液晶中非局域空间孤子的传输进行了理论研究.基于非线性液晶孤子传输方程，采用Gauss形式的试探解，不仅得到了空间孤子的解析解,而且还在临界功率附近得到了呼吸子的解析解.通过数值模拟证明我们的结果比Conti和Assanto等人的结果更合理.同时，对液晶中的非局域孤子模型和Snyder等提出的强非局域孤子模型进行了全面的比较. 关键词： 向列相液晶 空间孤子 非局域非线性 呼吸子     

椭圆响应强非局域非线性介质中的二维异步分数傅里叶变换及光束传输特性

研究了椭圆响应强非局域非线性介质中的光束传输问题. 结果表明:任意光束在这类介质中传输时均遵守二维异步分数傅里叶变换的传输规律. 基于二维异步分数傅里叶变换这一数学工具, 可很方便地对光束的传输进行解析求解并分析其性质. 利用二维异步分数傅里叶变换的性质, 讨论了一般光束的传输性质; 分析了孤子和二维异步呼吸子的形成条件; 得出了孤子/呼吸子的相互作用规律. 关键词： 椭圆响应 强非局域非线性 孤子 呼吸子     

一维分子链中激子与声子的相互作用和呼吸子解

运用连续极限近似，求解声子与激子相互作用的运动方程，得到了简谐分子链和 非简谐分子链中晶格振动的孤子解，在考虑三次非简谐势的情况下，一维分子链晶格振动具 有扭结孤子解，在考虑具有四次非简谐势的情况下，得到一维分子链晶格振动具有呼吸子解 . 关键词： 一维分子链 激子 声子 孤子 呼吸子 非线性效应     

(2+1)维Boiti-Leon-Pempinelle系统的钟状和峰状圈孤子

借助于Painlev Bcklund变换和多线性变量分离方法, 求得了(2+1)维非线性Boiti Leon Pempinelle系统的一般变量分离解．根据得到的一般解, 可以构建出丰富的局域相干结构, 如峰状孤子、紧致子等. 得到了两种新的局域结构——钟状圈孤子和峰状圈孤子, 并简要讨论了这两种圈孤子的一些特殊演化性质． 关键词： Boiti Leon Pempinelle系统 多线性变量分离法 钟状圈孤子 峰状圈孤子     

（2+1）维Sawada-Kotera方程中两个Y周期孤子的相互作用

利用双线性方法给出了2+1维Sawaka-Kotera(SK)方程的N孤子解.将N孤子解中的实参数扩大到复数范围，得到了该方程的呼吸子解，描述线孤子和y周期孤子相互作用的解和两个y周期孤子相互作用的解.从解析和几何两个角度探讨了两个y周期孤子的相互作用.相互作用性质和耦合系数有关.对于SK方程，耦合系数的取值只允许方程中存在弹性的排斥相互作用. 关键词： y周期孤子相互作用 SK方程 双线性方法     

槽中双孤子互作用的微扰求解

孤子运动的Miles方程是一个具特征的非线性Schrdinger型方程.借求孤子解的微扰法,导出所遵循的矩阵方程,和孤子解的修正量δu(x,λ).并据双孤子解,计算了它的周期互作用状态 关键词： Miles方程 微扰双孤子解     

Test theories of special relativity

We review the Edwards transformation, and investigate the Robertson transformation and the Mansouri-Sexl (ms) transformation. It is shown that thems transformation is a generalization of the Robertson transformation, just as the Edwards transformation is a generalization of the Lorentz transformation. In other words, thems transformation differs from the Robertson transformation by a directional parameterq, just as is the case for the Edwards and Lorentz transformations. So thems transformation predicts the same observable effects as the Robertson transformation, just as the Edwards transformation does with the Lorentz transformation. This is to say that the directional parameterq representing the anisotropy of the one-way speed of light is not observable in any physical experiment. The observable difference between thems (Robertson) transformation(s) and the Lorentz transformation is caused by the anisotropy of the two-way speed of light. Therefore a physical test of thems transformation is a test of the two-way speed of light, but not of the one-way speed of light.     

Study of the Thomas Equation: A More General Transformation (Auto–Backlund Transformation) and Exact Solutions

The famous Thomas equation, which arises in the study of chemical exchange processes, is investigated. A more general transformation (called auto-Backlund transformation), which contains the Thomas-Rosales transformation and the Wei-Gao-Zhang transformation, is presented. Based on the general transformation, we may find more information about this equation. Particularly some new exact solutions are found from the special form of the obtained transformation.     

非对易空间R2N的转动及其实现

给出非对易R^2N中坐标辛变换对应的幺正变换的实现;给出这种幺正变换引起的波函数的变化,也就是在Hilbert空间的幺正变换的矩阵元     

Martensitic transformation and shape memory effect of a Ni–Fe–Ga polycrystalline alloy

The martensitic transformation and shape memory effect of Ni—23.9 wt%–Fe—28.7 wt%Ga polycrystalline alloy are studied in the present paper. It is shown that martensitic transformation temperatures and its reverse transformation temperatures are all raised by annealing treatment. A large reversible transformation strain, about 2100ppm, is obtained in Ni—23.9 wt%–Fe—28.7 wt%Ga polycrystalline alloy due to martensitic transformation and its reverse transformation. This transformation strain is also increased by the external magnetic field. It is believed that the effect of field on the preferential orientation of martensitic variants when transforming increases the transformation strain.     

Rotation and Its Realization on Noncommutative Space R2N

In this paper,we present the realization of unitary transformation that is corresponding to symplectic transformation of coordinate on noncommunicative R^2N,and give out the transformation of wave function caused by the unitary transformation,i,e.,it is the matrix unit of unitary transformation.     

Bäcklund transformations of the axially symmetric stationary Einstein-Maxwell equations II

We obtained a Bäcklund transformation of the axially symmetric stationary Einstein-Maxwell equation which is a generalization of Neugebauer's I₁ transformation in the case of the Ernst equations. This transformation is shown to generate the generalized Ehlers transformation and the Harrison transformation.     

基于Karhunen-Loève变换和小波谱特征矢量量化的三维谱像数据压缩

提出了基于Karhunen Lo埁ｖｅ变换的小波谱特征矢量量化三维谱像数据压缩方法耍幔颍瑁酰睿澹?Lo埁ｖｅ变换 /小波变换 /小波谱特征矢量量化方法应用了Karhunen Lo埁ｖｅ变换的消除谱相关性优良性能 ,应用二维小波变换消除空间相关性 ,在小波变换域内应用二维集分割嵌入块编码和一维谱特征矢量量化对三维谱像数据压缩 ,获得较高的压缩性能。实验结果表明 :Karhunen Lo埁ｖｅ变换 /小波变换 /小波谱特征矢量量化编码比Karhunen Lo埁ｖｅ变换 /小波变换 /改进对块零树编码和Karhunen Lo埁ｖｅ变换 /小波变换 /快速矢量量化编码方法在同样压缩比条件下 ,峰值信噪比提高 2dB和 1dB以上 ,而速度提高了 1.5和 8倍 ,整体压缩性能有较大的提高     

Diffusion-controlled transformation plasticity of steel under externally applied stress

The transformation plasticity of steel during phase transformation under external stress was modelled on a migrating interface diffusion mechanism. Atomic diffusion along the migrating phase interface is assumed to cause transformation plasticity by an accelerated Coble creep. A creep equation on transformation plasticity is derived as a function of transformation rate, temperature and externally applied stress. Predictions are compared with dilatometric measurements during the austenite-to-ferrite and ferrite-to-austenite transformation of steel under various levels of uniaxial compressive stress. Good agreement was found between the calculated and experimental transformation strain. The model proposed also successfully describes the thermally activated behaviour of the transformation strain. The evaluated effective diffusion coefficients on the migrating interface are three to four orders of magnitude larger than those reported for stationary boundaries.     

Analysis of top-hat selection transformation and some modified top-hat transformations

This paper analyzes the relationships between top-hat selection transformation and some modified top-hat transformations. Firstly, several top-hat transformations following different applications are reviewed. Then, the relationship between top-hat selection transformation and each other top-hat transformation is analyzed and proofed. Finally, we show that some other top-hat transformations may be derived from top-hat selection transformation. Moreover, different parameter specifications of top-hat selection transformation result in different types of top-hat transformations, which may generate efficient top-hat transformations for different application purposes. Therefore, top-hat selection transformation is useful for the research and application of top-hat transformation.     

用相干光实现Walsh变换

本文采用相干光方法对Walsh变换进行了具体的实验研究。设计了五平面的相干光变换装置,实现了一维八序的Walsh变换,给出了变换频谱。对于二维Walsh变换原则上也是适用的。 关键词：