波阵面

The diorama of natural ground scene is modeled from the DEM data base on fractal theory and facet model.

在对地面场景，使用分形插值理论和小面单元模型来对实测的地面场景DEM数据进行处理，最后再利用地面散射特性模型结合地面场景模型和空间关系模型来计算地面场景的RCS数据阵，生成场景回波数据。

Using the Conservation Law of mass, momentum, energy in the form of Euler and equation of the thermodynamics, the interaction between the shock wave and the wall surface of the excavation roadway during the gas explosion is discussed.

文章建立了瓦斯爆炸冲击波的管道物理模型，利用Euler形式的动量、质量、能量守恒方程和热力学方程从理论上解析了瓦斯爆炸过程中爆炸冲击波与掘进巷道壁面相互作用中正反射和斜反射时波阵面上的各个参数，并给出了计算公式和简化公式。

The evolution of the half-peak width of the relative density increment pulse with respect to slow wave also demonstrates the close relation to Δp. Its minimum w〓 decreases with the increase of Δp, which means, slow wave will steepen with the enhancement of Δp and may evolve into slow shock eventually. Numerical results also indicate that the propagation velocity of fast and slow wave increase when Δp increases.

对强扰动情形(Δp＝5)，通过考察相关物理量的径向分布，并借助于对物理量沿波动阵面法向分布的讨论，可以初步判断出由强扰动所造成的慢模磁声波在传播过程中逐渐陡变而演化为慢激波，慢激波在进入日冕前已在色球层中形成，并在此后的传播过程中始终保持这一性质。

Both the offset and tilted fedcoupling-slot array between the curved guide and sectoral guides and longitudinal radiating-slot array on sectoral guide are analyzed by moment method, taking into account of the effects of finite wall thickness and mutual coupling between the slots, employing the acceleration algorithms to accelerate the summation of slowly convergent series of the self-admittance of the waveguide-slot aperture, and introducing the surface Fock functions to simplify the computation of the self-and mutual coupling of the slots on the surface of cylinder.

采用矩量法分别分析弯波导与扇面波导间偏置倾斜馈电耦合缝阵和扇面波导轴向辐射缝面阵，其中计及有限波导壁厚及缝间互耦的影响，运用级数加速算法对波导中自导纳矩阵元级数进行加速处理，并引入表面Fock函数简化圆柱面上缝口面的自耦和互耦的计算。

In view of the development about the certain airborne radar antenna array,considering the structural features of antenna array,analyse the cruces in manufacturing of feed cavity and radiant plate,and present the corresponding solution by mainly dealing with precise positioning style,delicate clamp design,error distribution and compensation method,high speed machining technology design,machining simulation and program optimizing.

某机载雷达平面裂缝阵列天线的单面阵如图1所示。该面阵布置多路裂缝线源，共分布384处长度各不相同的辐射裂缝，每一路线源均由脊型波导口单独馈电。面阵由辐射板和馈电腔两个零件组成，采用整体钎焊成形。线源结构为非对称单脊共线形式，即在普通单脊波导的两侧与辐射裂缝相对应的位置上布置不对称的凹台。

Raypath: A line everywhere perpendicular to wavefronts.

在均匀介质中与波阵面处处垂直的线。

During the last three decades, several models have been proposed to explain the formation of somites, including the clock and wavefront model, the reaction-diffusion type model, clock and induction model, clock and trail model etc. Although some of them are satisfactory in the different aspects of somitogenesis, no one can explain the formation and regulation of somites perfectly.

近三十年来，研究者们就体节的发生和发育提出了多种解释模型，这包括时钟波阵面模型，反应扩散模型，时钟诱导模型，时钟痕迹模型等，虽然这些模型能从不同角度不同程度来解释动物体节发生和发育的不同现象，但无一能够解释体节发生和发育的全部。

This assumption is reasonably justified in the early stages, when the wave front is not far from ground zero.

这种假定在初期阶段波阵面离地面零点不远时是相当合理的。

The Miyun metre-wave aperture synthesis radioteleseope, working at frequency of 232 MHz, consists of: an E-W array of 28 elements each of 9 m aperture. 192 baselines are effected with a full coverage of U-V plane (Fig. 2). The longest baseline is 1,164 m, This instrument is designed for source survey and detection of peculiar source in north declinations.

密云米波综合孔径射电望远镜工作在232MHz，由28面直径9米的东-西天线阵组成，天线阵全长1164米，u-v平面覆盖完整，适于进行北赤纬天区射电源普查及特殊源搜索。2×12小时观测得&热噪音限制&灵敏度0.05Jy，综合方向束3′。8×3′。8cscδ，视场8°×8°，可以在两年以内完成δ≥+30°天区的普查，并开展选区监测。

The method of measuring aerial camera photograph height and auto focuing using area array CCD and wavelet transform is proposed and the design scheme is given out.

提出了一种利用面阵CCD和小波变换理论测量航空相机摄影高度并自动完成相机调焦的方法。给出了实测系统的设计方案。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。