查询词典 wave propagation

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。

Characteristics of Lamb wave propagation in multilayered composite plates are influenced by many factors, the most important of which are: constituent properties, thickness and fiber orientation, the number of layers, and lay-up sequence and the direction of wave propagation.

层状各向异性板中Lamb波的传播特性受许多因素的影响，其中最重要的影响因素是：组层材料的性质、厚度以及纤维的方向、层数、层序、Lamb波传播方向。

Phase and group velocity are the important parameters for researching seismic wave propagation and describing the media property, and they are key contents in theory of elastic wave propagation and play a role in theory and application.

相速度和群速度是研究地震波传播规律和描述介质特性的重要参数，是弹性波传播理论中的核心内容，在理论研究和实际应用中有重要作用。

The propagation matrix method used widely in stratified media is extended to laterally inho-mogeneous media,and a numerical method known as generalized propagation matrix method for simulating elastic seismic wave propagation in inhomogeneous media is presented by using mixed variable elastic wave equation and matrix exponent solution of system of linear ordinary differential equations.

应用混合变量弹性动力学方程和线性常微分方程组的矩阵指数解法，将层状介质中广泛应用的弹性波传播矩阵解法推广至横向非均匀介质，给出了一种可计算复杂地质体中弹性波传播的广义传播矩阵数值解法。

The testing method comprises the following steps:(1) collecting the electrocardio-signal, the phonocardio-signal and the pulse signal of radial artery;(2) performing analog-to-digital conversion to the three signals to form the signal oscillogram;(3) identifying and extracting the characteristic point of each signal;(4) constructing the time series RR of electrocardio-period, the electromechanical delay time series and the pulse wave propagation time series of the combined variability index;(5) testing the validity of each time series;(6) calculating the heart rate variability, the electromechanical delay variability and the pulse wave propagation time variability; and (7) calculating the combined variability index of angiocarpy AV.

本发明提供了一种心血管系统联合变异性指标的检测方法和装置，检测方法包括以下步骤：(1)采集受检测者的心电、心音、挠动脉脉搏信号；(2)对三路信号进行模拟-数字转换，形成信号波形图；(3)识别和提取三路信号各自的特征点；(4)构造联合变异性指标的心电间期时间序列RR，电机械延迟时间序列和脉搏波传播时间序列；(5)检验各时间序列的有效性；(6)计算心率变异性、电机械延迟变异性和脉搏波传播时间变异性；(7)计算心血管联合变异性指标AV。

Depending on the character of Lamb wave propagation , thedamage scat tering signals were time reversed and reemit ted to the damage , and then they will arrive at the damage synchronously so that the damage scat tering signal caught again will be amplified. Details about the time reversal amplifying process were analyzed and given. Based on the focalization ability of time reversal theory to the wave origin , the wave propagation was rebuilt by an image method which displays the damage as the focusing point .

根据信号传播自身的特性，研究采用时间反转聚焦方法使损伤散射信号能量叠加放大，从而提高信号的信噪比，分析给出了具体的损伤信号时间反转聚焦增强过程；利用时间反转法对波源的自适应聚焦能力，重建信号传播波动图，通过信号聚焦显示损伤位置和区域。

Its wave propagation properties in symmetry and asymmetry structure are analyzed by 3-D EBPM including the analysis and study of the influence of refractive index to wave propagation. The bend fiber-slab is also studied in this paper and point that the influence of the refractive index of the substrate to wave propagation in fiber-slab is very important. The calculating results agree with the results of the test.

本论文利用三维显式光束传播法很方便地分析了对称、非对称光纤—光波导复合结构中光波的传输问题，包括光纤折射率的大小、光波导折射率的大小对光波传输的影响等在内的主要内容；随后又研究了光纤弯曲时光波导包层折射率对光纤内能量功率大小的影响，计算结果和实验结果吻合。

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。

Based on basic theory of elastic wave propagation, wave equation forpropagation of elastic wave in 2 dimension vertical inhomogeneous mediumof similar concrete cutoff wall model is developed. 2 dimension elastic sheetof concrete cutoff wall is established to research law and energy distributionrelations between propagation, attenuation, reflection and transmission ofelastic wave in concrete cutoff wall; Based on the concept of resolution, thecontent of vertical reflection method used to inspect concrete cutoff wallresolution is raised and factors will have influences on resolution are analyzed,expression of defective layer composite reflection factor and detectabledefective layer maximum thickness are developed; Relations between allsteps of sampling system of vertical reflection are build, the influence ofcentrum characteristics and receiving sensor on testing results are analyzed,therefore parameter requirements for testing instrument and parameter selection principle of collected parameters are raised.

2从弹性波传播的基本理论研究出发，推导了弹性波在类似混凝土防渗墙模型的二维垂向不均匀介质中传播的波动方程式；建立了混凝土防渗墙二维弹性薄板模型，研究弹性波在混凝土防渗墙中的传播、衰减、反射、透射规律及能量分配关系；从分辨率的概念出发，提出了垂直反射法检测混凝土防渗墙分辨率的内涵，对影响分辨率的因素进行了分析，推导出了缺陷层复合反射系数、可检测缺陷层极限厚度的表达式；建立了垂直反射法采样系统各环节之间的关系，研究分析了震源特性、接收传感器对测试结果的影响，提出了对测试仪器参数的要求及采集参数的选择原则。

Gravity wave and ozone are two interesting topics in the middle and upper atmosphere. In this dissertation, they are studied by numerical simulation and instrument development respectively.In section one, by using FICE scheme and TIME-GCM, a model of trace gases and OH airglow affected by gravity wave is set up, then the propagation of nonlinear gravity wave and the effect on trace gases and OH airglow are analyzed. The result shows gravity wave excited by tropospause forcing can propagate stably to the mesosphere through the stratosphere so that energy and momentum can be transferred from one region to another. In this process, gravity wave undergoes growth, overturning, convection and breaking. And the no-isothermal structure can accelerate the breaking of gravity wave in mesospause, and the breaking of gravity wave is an important source of convection and small-scale waves.

中文题名气辉的非线性重力波研究及臭氧总量探测仪的研制副题名外文题名 The study of airglow by nonlinear gravity wave and the development of the total ozone spectrometer 论文作者王咏梅导师刘振兴王英鉴学科专业空间物理学研究领域\研究方向学位级别博士学位授予单位中国科学院空间科学与应用研究中心学位授予日期2003 论文页码总数88页关键词臭氧气辉重力波馆藏号BSLW /2003 /P421 /7 重力波和臭氧是中高层大气中研究的两大热门课题，本文分别从理论模式和仪器研制两方面对它们进行了研究。

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。