在传播中

The stable wave-field propagators of one-way wave equation for Born and Rytov approximations are derived by using the local Born and local Rytov approximation methods in the scatter theory of wave-field propagation, and their application effects in prestack depth migration imaging of wave equation are compared theor...

利用波场传播散射理论中的局部Born近似和局部Rytov近似，分别导出了单程波方程的稳定的Born近似波场传播算子和稳定的Rytov近似波场传播算子，然后从理论和实践上比较了它们在地震数据波动方程叠前深度偏移成像中的应用效果。

Under the background of international internet era, China"s TV medium is facing with the new communication environments, China"s primary communication environments, including political, market, cultural and technique environments, appear new characteristics under the impact of cybernation.

在全球迈向"网络时代"的背景下，中国国内的电视媒体面临着新的传播环境，原有的传播环境包括政治环境、市场环境、文化环境和技术环境在网络化的冲击下逐渐呈现出新的特点；面对网络所带来的机遇和挑战，中国电视媒体正积极地寻求与网络相融互补，谋求更广阔的发展天地：一方面通过组建自己的媒体网站，实现信息的网络化传播，另一方面在积极的推进电视媒体的数字化、网络化进程，适应未来全球电视业的激烈竞争；本文对中国电视媒体初步实现网络传播的现状进行了总结，并就传播过程中呈现的问题、原因和应对的策略，提出了一些自己的看法，对未来可能呈现的发展趋势作出了预测和判断。

Research on development methods and application of CAD system of prac tical sheet metal expansion ;2. A frame expansion method of operator is used to the phase shift operator of split-step Fourier propagator.

针对裂步Fourier传播算子在速度强横向变化介质中的不足，将算子的框架展开方法应用于Fourier传播算子中的相移算子，提出了一种波场传播的局部裂步Fourier传播算子，并把它应用于波动方程叠前深度偏移成像。

Taletelling" is a typical form of oral communication,"acting", a comprehensive one and one of the perfect forms for human communication, and the "partly-versed novel , another form of the communication, as a middle style between the novel and drama; of course, the entrance of verses into the novel is not meant merely to stand close by the orthodox.

中国古代白话小说戏曲传播，虽然是发生在以文字为主要传播媒介的时代，却由于接受者的待殊性，语言一直是与文字同样重要的传播媒介。"说话"是口语传播最纯粹最典型的表现形式；"表演"是一种综合性的传播方式，也是人类传播活动中最完美的表现形式之一；"词话"是介于小说与戏曲之间的文体，却同时又作为小说戏曲的传播方式存在。

Thirdly, from the influences of Media Event, by reference to objective reporting ideas, this study analyzes in sequence these influences in terms of reporting practice, media management and control, and reporting ideas, to further explore how two aspects remodify themselves and coordinate to supplement, and perfect the system of news reporting ideas.

具体而言，一是从媒介事件的本体出发，在&媒介事件&同名概念的已有研究基础上，对本研究中的媒介事件加以概念上的厘清与界定，并将其框定在新闻报道理念及实践的双重层面中，从不同角度探讨&如何&呈现出&传媒→事实→报道&的新闻生产及传播关系；二是从媒介事件的历史出发，实际上是放置于新闻报道发展史中，解答&为何&繁衍出这种新闻传播现象并导致这种新闻生产及传播关系的问题；三是从媒介事件的影响出发，以客观报道理念为参照，分别从报道实践、传媒管理与控制、报道理念等角度对媒介事件的影响进行逐一辨析，考察媒介事件和客观报道理念如何各自修正并互为补充，从而进一步完善新闻报道理念体系。

Evidence suggests that 1 under more stable stratification, the basic flow, if moving faster at low and high levels (particularly in the presence of jets there), allows a resulting meso-β unsteady wave to propagate eastward with respect to basic flow and even at greater velocity compared with it; 2 vertical windspeed shear of basic flow causes instabilities of the TWT perturbation; 3 considering the second derivative of basic-flow wind with respect to z (denoted by zz≠ 0 which is simply given as β* hereafter) the expression for the phase velocity of vortex Rossby wave is obtained, which is unidirectional in propagation with respect to basic flow; 4 VRoW has its physical origin from β*, i.e., from z-varying heterogeneities of y-direction averaged vorticity of the basic flow field; 5 VRoW phase velocity is associated with zonal wave number k, its energy is dispersive and the group velocity exists in the x direction; 6 when windspeed meets the condition of β*, TWT disturbance instability may be that of mixed VRoW and gravity wave; 7 if basic flow is subject to linear shear but does not meet the condition of β*, the TWT instability is that of inertia-gravity wave.

在大气层结比较稳定的情况下，如果基本气流在低层和高层较大(有可能存在低空急流和高空急流)，此时产生的β中尺度不稳定扰动相对于基流向东传播，甚至于快速向东传播。基本气流在垂直方向上的风速切变对于中尺度横波型的扰动起着不稳定的作用。如果考虑基流的二次切变，可以得到涡旋Rossby波的相速度表达式，涡旋Rossby波相对于基本气流是单向传播的。涡旋Rossby波产生的物理根源是基本流场的风速二次切变，亦即基本流场y方向的平均涡度在空间z方向上的不均匀所致。涡旋Rossby波的相速度与纬向波数也有关，它的能量是频散的，其在纬向x方向也存在群速度。在基本流场的风速存在二次切变时，横波型不稳定可能是混合的涡旋Rossby重力波的不稳定；而在基本流场的风速仅仅存在线性切变，不存在二次切变时，横波型扰动的不稳定则是重力惯性波的不稳定。

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。

Firstly, because the triangle constrained matching propagation begins with the initial corresponding triangulations formed by a few seed points in the stereo pairs, this dissertation studies the affects of different numbers and different distributions of seed points on the image matching results through experimental analysis, and proposes a seed point selection strategy for different image texture conditions, an automatic selection algorithm is also designed that gives good distribution quality for a defined number of seed points.

首先，针对匹配传播过程中的种子点选取问题，通过实验分析研究了不同数量与分布的种子点所构成的初始三角网对匹配结果的影响，进而提出了不同影像条件下的种子点选取策略和一种自动提取一定数量、满足一定分布均匀度的种子点自动选取算法；其次，研究了海量数据情况下同名三角网的快速构建、数据组织存储与局部动态更新的方法；在此基础上，本文提出了随机传播、基于三角形拓扑关系的邻近传播和顾及纹理特征的自适应传播等三种传播策略，分别介绍了其详细的实现算法，并通过实验分析对这几种传播策略进行了比较，实验结果证明自适应传播方法在匹配的可靠性上最优。

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。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。