脊波

The information Radon coefficient wrap-around of the line on a finite field was caused by the modular arithmetic so that the Radon coefficient information in the periodic oscillations direction was processed with discrete cosine transformation, and other direction information was processed with wavelet analysis in order to reduce the wrap-around of rebuilding information. At the same time, according to the characteristic of the noise, one kind of denoising threshold selection plan was proposed.

正交有限脊波分析处理信息时，有限域平面上的直线由于模运算的存在而引起信息Radon系数的卷绕，为此，对Radon系数周期振荡方向的信息采用离散余弦变换处理，其他方向信息采用小波分析处理，以减少卷绕对信息重建影响；同时，结合图像信息中噪声的特点，提出了一种去噪浮动阈值的选取方案。

According to the field plot of TE10 wave mode in rectangular ridged waveguide,the equivalent capacitance and equivalent inductance are approximately calculated by quasi-static method,and the resonant frequency which is namely cutoff frequency is derived.

由矩形正脊波导中主模TE10波模的分布结构特征，用准静态方法近似的计算出等效电容和等效电感，从而计算出谐振频率，也就是矩形正脊波导的截止频率。

Based on a localization principle and subband decomposition, monoscale ridgelet and curvelet were proposed, both of which were derived from ridgelet transform and can efficiently deal with smooth images with smooth edges including straight and curve singularity. They, hence, are of better application potention. sparse representation;optimal basis;ridgelet;curvelet;image denoising;non-parametric estimation

单尺度脊波和Curvelet变换由脊波变换发展而来，分别利用了函数局部化和频带剖分的思想，将脊波理论发展到了一个更高的阶段，这两种变换都能"近似最优"的表示直线和曲线奇异，因而具有更好的应用前景。

Various kinds of water rippleswere formed on the sediments,including straight-crested,undulatory,lingoid and rhomboid ripples by the action of water flow.

水流的作用产生各种水流波痕，包括直脊波痕、波曲波痕、舌形波痕和菱形波痕。

Firstly, the definition of image representation, measure of sparsity, and the basic methods of sparse representation are reviewed. And then, we analyze the performance of nonlinear approximation of Ridgelet, Curvelet, Contourlet and Bandelet transform.

论文阐述了信号表示的定义、稀疏性度量以及图像稀疏表示的基本理论方法，分析与比较了脊波变换、曲线波变换、Contourlet变换、Bandelet变换各自的非线性逼近性能。

Several digital ridgelet transforms are compared in this paper.

本文著重比较脊波变换的几种不同数字实现及对於小波的改进。

Several digital ridgelet transforms are compared in this paper.

本文着重比较脊波变换的几种不同数字实现及对于小波的改进。

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。

An approximate analytical approach, which can be used to analyze the optical characteristics of metal-clad step or graded index waveguides in near cutoff, is presented at first. The mode propagation characteristics of metal-clad step index waveguides in near cutoff are comprehensively analyzed.

GaAs/GaAlAs异质结光波导材料是目前集成光学中的重要材料，本论文在系统介绍外延生长技术的基础上，利用普通的液相外延炉，成功地生长出可用于光波导器件制作的、表面较光滑并具有较大面积（14×16mm〓）的GaAs/GaAlAs异质结光波导材料，C-V法测得波导层载流子浓度为2—4×10〓cm〓，Al-Schottky接触的反向电压大于20伏，平板波导和脊波导通光实验良好。

The integrated optical chip we designed in the dissertation is composed of a symmetrical Y-branch power splitter, two phase modulators and the TE/TM mode polarizer. Here the up-electrode of phase modulator covers the rib waveguide directly. For the metal-cladded rib waveguide, the loss of different mode is different.

由于相位调制器采用上下电极结构，上电极直接覆盖在脊波导之上；因此利用金属覆盖的脊波导对不同偏振模式的光具有不同的传输损耗这一特性，将相位调制器的上电极同时作为TE/TM模式偏振器使用，这样无需制作额外的偏振器，整个器件的尺寸可以减小。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。