向内发射同轴型二极管电流电压关系二维修正

 给出了对同轴型强流电子束二极管的电流电压关系进行的部分理论推导与介绍,同时利用PIC数值模拟以及实验研究得到的二维效应修正关系曲线。在研究中首先给出了对向内发射同轴型二极管在不同电压等级下的电流电压关系,然后用PIC数值模拟方法进行验证。对数值模拟的结果也给出了理论推导公式在不同状态下的二维效应修正因子与电子束流运动的特点。在研究中得到的电流电压关系理论公式基本上反映了不同条件下同轴型二极管的束流特性,所以此研究结果可以直接应用于包含同轴型二极管结构的脉冲功率器件的设计与实验结果的分析中,为实验中相关问题的解决提供设计的依据与理论分析基础。     

Explicit and exact travelling plane wave solutions of the （2＋1）—dimensional Boussinesq equation

The deformation mapping method is applied to solve a system of (2+1)-dimensional Boussinesq equations. Many types of explicit and exact travelling plane wave solutions, which contain solitary wave solutions,periodic wave solutions,Jacobian elliptic function solutions and others exact solutions, are obtained by a simple algebraic transformation relation between the (2+1)-dimensional Boussinesq equation and the cubic nonlinear Klein－Gordon equation.     

Coherent soliton structures of the (2+1)-dimensional long-wave－short-wave resonance interaction equation

The variable separation approach is used to find exact solutions of the (2+1)-dimensional long-wave－short-wave resonance interaction equation. The abundance of the coherent soliton structures of this model is introduced by the entrance of an arbitrary function of the seed solutions. For some special selections of the arbitrary function, it is shown that the coherent soliton structures may be dromions, solitoffs, etc.     

New results of some existence theorems on nonlinear boundary value problems

IntroductionSeveralpapershavebeenwrittenaboutequationwhereLisalineardifferentialexpression,NacontinuouslyFrechetdifferentialoperatorsuchthatL N'(u)satisfiescertainconditions,andFanoperator,usuallywithboundedrange.AconcreteexampleiswhereLisaseconddifferentialoperator,gsatisfiessomeconditionsrelatingtoL,andfisbounded.AmainlyusedtechniqueisSchauderfixedpointtheorem.Byestablishingapriorbound,itisnaturaltoobtaintheexistCnceofthesolutions.Butthismethodcannotgettheuniquenessofthesolution,noristh…     

Duffing型方程组的边界值问题的解的存在性

给出了带Dirichlet边界条件、Neumann边界条件和周期边界条件的Duffing型方程组的两点边界值问题的解的几个存在性定理。     

螺旋线型微秒级高压长脉冲产生器数值模拟北大核心CSCD

探索了采用CST软件和PSpice软件进行加速器场分布数值模拟的方法,利用该方法可方便地获取设备内部动态场分布图及动态电压变化规律。针对螺旋线型μs级高压长脉冲产生器系统建立了数值模拟模型,给出了详细的模拟步骤及结果。分析表明,利用场分布模拟方法获取的电压变化规律与电路模拟方法获取的结果是一致的。基于CST模拟方法,可以给出螺旋线及主开关等电气结构的瞬态电场分布,场强增强点主要出现在螺旋带的外沿及金属电极连接处,在介质支撑内部也有较高的场强分布。