一个求解P＊（k）水平线性互补问题精确极大互补解的不可行内点算法

Stoer,Wechs,和Mizuno最近提出了一个求解P*(k)水平线性互补问题 的不可行内点算法,他们的算法能在有限不内得到问题的一个精确解,但是没有讨论算法的多项式复杂式。本文提出一个能得到P*(k)水平线性互补问题精确极大互补解的不可行内点算法,通过使用条件数和误差界理论,我们证明了所给算法是多项式有界的。     

激光束干扰成像制导导弹的计算机仿真研究

介绍一种激光干扰计算机仿真系统.首先针对不同背景和导弹的光电系统建立反射模型,在用户给出条件参数下,计算出反射信号幅度的空间和时间分布.再通过对大气传输模型,根据用户给的大气环境参数,计算出最终回波信号的空间和时间分布,提供给目标识别和跟踪程序处理.这样用户可以以计算机仿真的方式来确定其目标判别方法的有效性. 为对干扰效果进行仿真对强激光的斜程大气传输和导弹最常用的一些成像器件的光电响应特性建立了模型,以用户指定的条件参数和精度进行运算,最终提供给用户在不同干扰方式,干扰强度下导弹成像器件的输出在空间和时间上的分布.这样用户可根据成像器件的输出来确定具有最好干扰效果的激光干扰器的工作方式. 整个仿真系统建立在大气传输特性及成像器件光电相应特性参数数据库基础之上,其中包括了大量常用的计算用参数数据.可对激光束干扰成像制导导弹的关键问题即探测方式和干扰方式的确定起到辅助作用.(PG11)     

Non-Lie Symmetry Groups of （2＋1）-Dimensional Nonlinear Systems

A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physics systems. Applying the modified direct method to the well-known （2＋1）-dimensional asymmetric Nizhnik-Novikov-Vesselov equation and Nizhnik Novikov-Vesselov equation, both the Lie point symmetry groups and the non-Lie symmetry groups are obtained. The Lie symmetry groups obtained via traditional Lie approaches are only speciai cases. Furthermore, the expressions of the exact finite transformations of the Lie groups are much simpler than those obtained via the standard approaches.     

Exact periodic wave and soliton solutions in two-component Bose--Einstein condensates

We present several families of exact solutions to a system of coupled nonlinear Schr\"{o}dinger equations. The model describes a binary mixture of two Bose--Einstein condensates in a magnetic trap potential. Using a mapping deformation method, we find exact periodic wave and soliton solutions, including bright and dark soliton pairs.     

A Series of Exact Solutions for a New （2＋1）-Dimensional Calogero KdV Equation

An algebraic method is proposed to solve a new （2＋1）-dimensional Calogero KdV equation and explicitly construct a series of exact solutions including rational solutions, triangular solutions, exponential solution, line soliton solutions, and doubly periodic wave solutions.     

基于系数逼近的差分格式

对于变系数微分方程,在每个离散子区间上用函数去逼近系数比用一常数去代替系数,所得到的一系列近似微分方程有更高的精度．通常的差分格式建立在解函数在子区间上的Taylor展开式的近似的基础上,这样要求函数相对于网格是缓变的．而基于系数Taylor展开的近似式和局部基的引入,使得方法能在子区间上精确表达比二次函数丰富得多的解函数．由此构造的差分格式能在子区间上反映解具有迅速变化（如边界层,高振荡）的复杂的物理现象．数值实验（边值问题、特征值问题）显示了新方法比传统方法有更满意的效果．     

New Exact Solutions of Broer-Kaup Equations

By a known transformation, (2 1)-dimensional Brioer Kaup equations are turned to a single equation.The classical Lie symmetry analysis and similarity reductions are performed for this single equation. From some of reduction equations, new exact solutions are obtained, which contain previous results, and more exact solutions can be created directly by abundant known solutions of the Burgers equations and the heat equations.     

New Exact Solutions of Broer-Kaup Equations

Based on a known transform, the exact solutions of (2 1)-dimensional Broer-Kaup equations are investigated by using the method of direct integral. A kind of new exact solutions of Broer Kaup equations are obtained,which contain previous results about solitary wave solutions.     

Auto-Backlund Transformation and Exact Solutions to the Generalized Kadomtsev-Petviashvili Equation with Variable Coefficients

By using the extended homogeneous balance method, a new auto-Ba^ecklund transformation(BT) to the generalized Kadomtsew-Petviashvili equation with variable coefficients (VCGKP) are obtained. And making use of the auto-BT and choosing a special seed solution, we get many families of new exact solutions of the VCGKP equations, which include single soliton-like solutions, multi-soliton-like solutions, and special-soliton-like solutions. Since the KP equation and cylindrical KP equation are all special cases of the VCGKP equation, and the corresponding results of these equations are also given respectively.     

激光主动成像制导雷达的研究方向

文中介绍了国外制导用激光成像雷达近年来的发展情况,总结提出了激光主动成像制导雷达的研究方向。ＣＯ２激光成像雷达系统效率高,大气传输性能好,信息处理技术成熟,易于实现高灵敏度外差探测和三维成像,曾经是主要的研究对象;固体激光雷达系统具有系统质量轻、价格低,探测器不需要制冷的独特优点正成为现在研究热点;二极管激光成像体积小,造价低、寿命长、可靠性高、功耗低,可采用室温探测,有着很大的发展前景。