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On the basis of comparison of several algorithms of the calculation of unstable resonator"s mode. Fast Fourier transform method is chosen in this paper. The model of multi-layer distribution of gain is established. Sampling granularity in real space used in FFT, quotient of guard band and distance between subsections are made certain respectively. The convergence criterion of root-mean-square of plural y which is the quotient of the optical field"s distributions separated by one pass is established. Under the circs of multi-kind of distribution of gain and different measurement of distortion, the output optical field distribution is calculated.

在比较了各种计算腔模方法的基础上，根据角谱传播理论，选择FFT算法，建立谐振腔内多层增益分布模型，分别确定了FFT算法的空间采样间隔、保护带系数和分段计算的距离，选取光场往返一次之比的均方根值收敛准则，计算多种增益分布、不同镜面变形时的谐振腔输出光场分布，同时计算该光场的远场分布和传输有限距离之后的分布。

In order to overcome this problem, in this paper, the surface electric current of the conducting sea surface and the first-order scattering from the conducting plate are obtained by employing Physic Optics method. The backscattering field of the time-dependant sea surface is calculated by using Kirchhoff Approximation. Meanwhile, taking the advantage of a newly developed technique that utilizes the reciprocity theorem, the difficulty in formulating the secondary scattered fields from the composite target is reduced. The dependences of the backscattered field on the parameters, such as the wind speed and the sizes of the plate are discussed.

为了克服这一问题，本文应用物理光学近似求解了导体海面表面电流及导体平板的一阶散射场，应用基尔霍夫近似给出了海面的后向散射场，同时借助互易性定理降低了求解平板和海面之间二次耦合散射场的难度，讨论了平板尺寸、风速等对后向复合散射场的影响。

The conventional numerical simulation of a reverberant field as a launch acoustic environment was introduced. Following the reciprocity theorem used in the coupled FE-BE model, the structural response due to reverberant acoustic excitation was substituted by the sound pressure caused by force excitation on the structure, then the output response power spectrum density of the coupled model subjected to reverberant environment was evaluated based on the stochastic analysis principle.

首先介绍了传统的构建混响声场的数值模拟方法；其后利用声振耦合中的互易定理，将混响声场的激励问题转化为结构模型上力激励引起的场点声压响应问题，并采用随机分析原理，用谱分析方法推导了结构在混响声场激励下的响应计算公式；最后建立了航天器典型结构的声振耦合模型，并分别用传统方法和利用互易定理的方法进行了数值模拟。

The lining point in riprap slope has opposite trend with the wind of itself.

在护坡内外层点的温度场与该点风场呈现出相反的变化趋势，内层点的温度场与该点风场呈现出相同的变化趋势。

In rare earth electrolysis cell , there exist complicated physical fields, and current field is root of other fields.

稀土电解槽中存在着复杂的物理场，而电场是其他物理场的根源，热场、流场是决定稀土电解槽的电解是否能进行的重要因素。

It is shown from this thesis that flow fields on synoptic maps can be decomposed into rotation and deformation fields. Geostrophic non-frictional cyclone and anticyclone vortex patterns are closed circulations around the center point, streamlines of frictional cyclone and anticyclone patterns have spiral forms around the focus point. Saddle fields have four vortex centers (two cyclones and two anticyclones) and a saddle point. Blocking high pressure and cut-off low pressure patterns consist of a vortex center and a saddle point.

本文说明了天气图上的流场可以分解为旋转场和变形场：地转无摩擦的气旋、反气旋的涡旋型式是围绕中心点的闭合环流；考虑摩擦的气旋、反气旋的流型是围绕焦点的螺旋型式；鞍型场有4个涡旋中心点（2个气旋和2个反气旋）与1个鞍点；阻塞高压和切断低压由1个涡旋中心点与1个鞍点组成。

Based on the aberration theory of AWG, a new-type flat-field AWG is designed. The focal signals of all wavelengths of operation are focusing along a straight line perpendicular to the propagation direction. Three stigmatic points restrain three dominant geometry parameters. Furthermore, a new-type flat-field wavelength router with both flat input field and flat focal field is also designed.

基于阵列波导光栅的像差理论，利用三个无像差点约束三个主要结构参量，设计了新型平场聚焦阵列波导光栅，使得所有工作波长的输出信号都聚焦在与光束传输方向垂直的直线上，并进一步将其拓展为同时具有平输入场和平聚焦场的新型平场波长路由器。

The Timberwolves have reached 100 just once in their last nine games and eight of 23 overall.

而森林狼在过去9场比赛中只有1场得分超过100，而所有23场比赛中也只有8场超过100。

The technology of landfill closure was discussed,with analysis of the unit components and function of landfill closure system.

探讨了垃圾填埋场封场工程中的封场覆盖技术，分析了封场覆盖系统各组成部分的结构组成和功能，提出了封场覆盖系统的工程质量控制措施。

A comparison is made between the electrostatic field and universal gravitation field to find out the very similarities between them.

在比较静电场与万有引力场相似性的基础上，归纳出相似性的本质，进而根据相似性由静电场中已有的公式、定理及解题方法推导出万有引力场中与此相似的公式、定理及解题方法。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。