波的传播

As the foundation of ultrasonic testing of composite materials, this thesis is intended to explore in detail a number of features of wave propagation in anisotropic plates, and the following essential problems will be considered:(1) Propagation of plane bulk waves in homogeneous and orthotropic anisotropic media;(2) Lamb wave propagation in multilayered anisotropic plates;(3) Influence of isotropic solid or liquid loading on Lamb wave propagation in anisotropic solid media;(4) Influence of interface layers on Lamb wave propagation in layered anisotropic composite laminates;(5) Dispersion characteristic analysis of attenuation Lamb wave while existing an thin viscous layer which is used for simulating the poor curing in adhesively bonded joints.

作为复合材料超声检测的基础，本文研究了如下国际前沿性的课题：（1）平面体波在正交均匀各向异性媒质中的传播；（2）多层各向异性媒质中Lamb波的传播；（3）各向同性固体或液体负载对各向异性固体媒质中Lamb波传播的影响；（4）界面层对层状各向异性复合媒质中Lamb波传播的影响；（5）胶粘剂未固化而呈现粘弹性时粘接结构中衰减Lamb波的频散特性分析。

In addition,the dispersion relation and delay characteristics of the coupled mode in two different YIG films are studied by numerical analogue in the range of inclination angle from 5° to 20°.

本文研究了在倾斜静磁场作用下，双层YIG薄膜波导结构中静磁体波的传播特性，得到了其色散的特征方程，计算了磁场倾角从5°到20°范围内双层波导结构中静磁体波传播的色散关系和延迟特性。

The propagation of elastic wave in a cylindrical bore hole containing a fluid (for example, the muddy fluid is generally used) for acoustic logging is analyzed with a simplified model.

本文分析了简化模型下声波测井时裸眼井中弹性波的传播，此波场可看成是轴向传播有不同波矢的分波的叠加。

Assuming the initial background is an isothermal and hydrostatic equilibrium atmosphere in which the horizontal pressure gradients are balanced by the geostrophic winds, we study the nonlinear propagation characteristics of the gravity waves, analyze the influence of the earth's rotation on the propagation of gravity wave and compare the simulation results with that obtained by the linear gravity theory.

假设初始背景是满足流体静力学平衡和地转平衡的等温大气，我们研究了重力波的传播特性，分析了地球旋转效应对重力波传播的影响，将模拟结果与线性重力波理论给出的结果及实验观测结果进行了比较。

The results of 3-D numerical modeling of the transversely isotropic media with horizontal symmetry axis and the orthorhombic symmetry media showed that quasi P wave,quasi-SV wave and quasi-SH wave occurred during elastic wave propagation in 3-D anisotropic media. Meanwhile, the special phenomena such as the S wave splitting, the blind zone of S wave splitting and quasi-SV wave-front triplication were clearly observed. In addition, the elastic wave-fronts are spatially changed, and the coupled relations among the quasi-P wave,quasi-SV wave and quasiSH wave in 3-D anisotropic media are very complex.

对方位各向异性介质模型和正交各向异性介质模型中弹性波的传播进行的三维数值模拟结果表明，弹性波在三维各向异性介质中传播时存在拟P波、拟SV波和拟SH波，并出现横波分裂、横波分裂盲区、波面三分叉等特殊现象，另外，性波场在空间是变化的，其拟P波、拟SV波和拟SH波的耦合关系比较复杂。

Firstly, the paper, combining the characteristic of synchronous pulse bursts and inhibition with the modified PCNN model, presents a way of finding the foveation points in the images adaptively and effectively, and simulates the human vision system. Secondly, PCNN is extended to PCNNs, based on the properties of information couple and transmission, an algorithm that is used to fuse images of the same target got by several sensors to an image is presented to simulate the human vision system. Thirdly, combining the properties of synchronous pulse bursts, capture, and transmission and competition of waves, the paper presents two ways of classification, one is an algorithm based on the properties of neuron to capture and inhibit to classify the data taking on any complex unlinear distribution robustly, the other is based on the restricted distance and modified of the former to remove the influence of inferior samples in classification; Finally, based on the accumulative difference pictures, and the forming and transmission of PCNN wave, selecting and controlling the direction of autowave by connecting the neighbouring neurons selectively, the paper presents a way to simulate the tracks of moving object and detect the moving direction.

首先结合PCNN的同步脉冲发放和侧抑制特性，提出了基于改进型PCNN的图像凹点检测算法，该算法是一种自适应而有效的图像凹点检测方法，并且较好地仿真了人类视觉系统；然后，结合信息传递和信息耦合特性，将PCNN扩展成PCNNs，提出了一种基于PCNNs的图像融合算法，能够将多个传感器获取的同一目标的图像信息融合到一幅图像中，有效模拟了人类视觉系统；另外，结合PCNN的同步脉冲发放特性、捕获特性和波的传播竞争特性，开拓地将PCNN用于模式分类中，提出了基于耦合神经元点火捕获／抑制特性的分类方法和改进的约束距离下的PCNN分类方法，前者可实现对样本空间中任意复杂分布训练样本的稳健非线性分类，而后者能够消除训练样本中刺点对分类的影响；最后，结合累积差分图像思想、PCNN波的形成与传播特性，通过各神经元之间连接取向来选择与控制自动波的流向，将PCNN用于运动视觉分析中的运动轨迹模拟及运动方向检测。

For strong disturbance case in which Δp is set to be 5, by examining the distributions of relevant physical quantities along radial direction and the normal of wave front, we can infer that the slow wave introduced by the strong pressure pulse steepens into slow shock during the propagation process.

与二维情形类似，沿由源区出发的径向，可以分辨出压力脉冲增长相所引起的前导快波与后随慢波的传播，同时还可观察到压力脉冲恢复相所导致的快模磁声波的传播，由于传播速度的差异，该波动在向外传播的过程中逐渐超过后随慢波。

In an oil well, the casing is a steel circular pipe, and it would confine and guide the electromagnetic wave propagating; and the electric properties of the fluid media would determine the propagation factor of the guided wave and affect the distribution state of the electromagnetic field.

油井内的套管是钢铁质圆管，对电磁波的传播将产生限制和引导作用；油井内流体介质的电性质将决定导波的传播常数，影响电磁场在井的轴向上和横向上的分布状态和波的传播特性。

The OH airglow volume emission rate has an obvious response to the breaking gravity wave and atomic oxygen.

在重力波的传播过程中，氢氧大气成分的水平和垂直分布均受到了不同程度的影响，以氧原子的响应最为明显，而其中重力波破碎在氧原子水平分布上的反应则是非线性重力波过程的一个重要表现；另外，分析显示，重力波的非线性传播对OH气辉的峰值分布由明显影响，小尺度重力波的传播有时会引起OH气辉出现奇异的双峰分布，重力波的破碎现象也可以从对气辉的观测中反映应出来，这对利用气辉观测研究重力波传播特性有非常重要的指示意义。

The breaking of gravity wave accelerates the downward transport of atomic oxygen, some smaller-scale structures appear on the horizontal distribution of atomic oxygen number density , and other chemical species are also affected due to the chemical reaction with atomic oxygen and the propagation of gravity wave. The OH airglow volume emission rate has an obvious response to the breaking gravity wave and atomic oxygen. The nonlinear propagation of smaller vertical wavelength gravity waves can induce the double-peaked structure in the OH airglow. The results can explanation some sporadic measurements of OH airglow and can provide a good indication for studying the characteristic of nonlinear gravity wave by using OH airglow measurement.

在重力波的传播过程中，氢氧大气成分的水平和垂直分布均受到了不同程度的影响，以氧原子的响应最为明显，而其中重力波破碎在氧原子水平分布上的反应则是非线性重力波过程的一个重要表现；另外，分析显示，重力波的非线性传播对OH气辉的峰值分布由明显影响，小尺度重力波的传播有时会引起OH气辉出现奇异的双峰分布，重力波的破碎现象也可以从对气辉的观测中反映应出来，这对利用气辉观测研究重力波传播特性有非常重要的指示意义。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。