查询词典 combination frequency

The results show that the Ni-Fe coatings are acid-resistant to HNO3 and H2SO4.For Ni-Fe alloys without exfoliation,the EIS is composed by a capacitive arc at high frequency and an inductive arc at low frequency, and the radius of capacitive arc decreases rapidly and the inductive component weakens and disappears with time.

结果表明：Ni-Fe合金镀层具有良好的耐酸腐蚀性；在3.5wt%NaCl溶液中，腐蚀发生之前的镍铁合金镀层的电化学阻抗谱由一个高频容抗弧和一个低频的感抗弧组成；随着浸泡时间的延长，容抗弧半径快速减小，感抗弧减弱并消失。

For AA8090 alloy without exfoliation , the EIS is comprised by a depressed capacitive arc at high frequency and an inductive arc at low frequency, and the inductive component weakens and also disappears with time.

结果表明，剥蚀发生之前，AA8090合金电化学阻抗谱由一个压缩的高频容抗弧和一个低频感抗弧组成，且低频感抗成分随浸泡时间延长而减弱并消失；一旦发生剥蚀，其电化学阻抗谱即由一个高频和一个低频两个容抗弧组成。

A series of theoretical and experimental studies on the microstrip patch antennas with dielectric superstrates is carried out systematically. Firstly, a comprehensive survey of the microstrip antenna technology and its theories are presented. Then, two analysis techniques, named as the spectral domain Green's function method and the spectral domain integral equation method are developed. The SDGF method is a simplified analysis technique, which takes advantage of the spectral domain immittance approach to find the dyadic Green's function for the stratified media, and obtains the complete closed-form formulas for radiation patterns, directivity, efficiency, gain etc. Some interesting calculated results are presented. The SDIE method is capable of determining resonant frequency, radiation characteristics, input impedance etc, for the covered microstrip patch antennas. Comparing with other full-wave analyses it reduced computation and mathematical labour remarkably. The singularities near the pole location of the surface-wave modes and the difficulty of the integral computation over infinite range of oscillating integrands are dealt with actively and documented well. Results predicted by the SDIE method agree extremely well with our experimental results for resonant frequencies of various superstrates. The superstrate effects on impedance and radiation characteristics also have been investigated experimentally so that the gap due to lack of measured data and computed results for multi-layered superstrate has been filled to some degrees and two useful observations have been achieved for weakening the resonant frequency shift and optimizing the microstrip antenna gain. As a meaningful application, the design and analysis of a 4×4 patch array are introduced.

实用微带天线普遍加介质覆盖层来防护热，物理损伤和环境影响，也可能在飞行或严酷气候条件下自然形成覆盖层本论文对带介质覆盖层的微带贴片天线系统地作了一系列理论和实验研究首先，对微带天线技术和理论作了全面的综述然后，发展了两种分析方法，称为谱域格林函数法和谱域积分方程法SDGF法是一种简化的分析技术，它利用谱域导抗法来求得分层媒质的并矢格林函数，并得出方向图、方向性系数、增益等参数的完整的闭式公式，给出了一些令人感兴趣的计算结果SDIE法能确定介质覆盖微带天线的谐振频率、辐射特性和输入阻抗等与其它全波分析方法相比，它明显减小了计算量和数学工作量已有效地处理了表面波模极点附近的奇异性和对振荡的被积函数的无限区间积分计算的困难对于不同覆盖层情况下的谐振频率，由SDIE法所预示的结果与我们的实验结果吻合得很好对于覆盖层对阻抗和辐射特性的影响也已作了实验研究这在某种程度上填补了缺少实验数据和计算结果之间的间隙，并得出了缓解谐振频率偏移和优化天线增益的两点有用的结论作为有意义的应用，介绍了一个4×4元矩形贴片天线阵的设计和分析。

The paper introduced the basic concept and theory of model analysis and structure dynamic analysis;performed the model analysis of the whole framework of hydraulic pressure and calculated the first ten-rank inherency frequency and corresponding vibratory-type;analyzed and estimated the first three-rank inherency frequency and corresponding vibratory-type of hydraulic pressure.

对液压机的整体机架进行有限元模态分析，得到了机架的前十阶固有频率和相应的固有振型，并对前三阶固有频率和振型进行了详尽的分析和评价。

He showed us a video frequency in which the CEO of Microsoft shouted crazily before a conference.At first, all of us laughed at the insaneness of the CEO, but when we heard the man in the video frequency said,"I love this company", and at the same time we heard Liu Chang's explanation,we fell in silence. Beyond the laughter, we were deeply impressed by the power and charm of the enthusiasm. We will benefit from it in our whole life.

他还播放了一个微软CEO在开会前近乎疯狂的大叫的视频，在视频播放的前面阶段里，大家都在为那个CEO的疯狂而感到好笑，但转到最后当视频里的人说"I love this company "以及刘畅的解说时，现场安静了下来，笑声之外，我们更多的收获是知道了热情的力量，热情的魅力，这将是我们一生都受用不完的。

Comparisons reveal that: plan of GSM Modem is fit for circumstances of low communicating frequency , insensitiveness of data delay and low cost; plan of GPRS DTU adapts to occasions of high communicating frequency, low delay, large data flow and restrict requirement of security.

比较的结果表明，GSM Modem方式适合于通讯频率小，数据延迟不敏感，费用低的场合；GPRS DTU方式适合于通讯频率大，数据延迟小，数据量大，安全性要求高的场合。

The low-frequency instability in variable speed constant frequency doubly fed induction generator which is widely used in wind power generation is studied.

研究了广泛应用于风力发电的变速恒频双馈感应电机系统中的低频不稳定现象。

The instantaneous frequency of a real signal is one of the most important concepts in time-frequency analysis.

瞬时频率是时频分析中的核心概念之一，它的定义也一直是信号处理领域的理论难题。

The transfer matrix and diffractive integral formula in frequency domain were acquired by rotating the input and output optical field π/2 in the phase space. Accordingly the fractional Fourier transforms of a first-order optical system in frequency domain were also obtained.

通过将输入输出光场在相空间中作π/2角旋转，得到了一阶光学系统在频域的传输矩阵和衍射积分公式，进而得到了一阶光学系统在频域的分数傅里叶表示。

The methods of adaptive median filter, variance ratio of interclass and intraclass segmentation, and mathematical morphology were used to decrease the noise of original welded seam image, to extract welded seam region, and to carry on high frequency enhancement transformation for the interior of extracted welded seam with frequency range sharpening.

利用自适应中值滤波方法和类间、类内方差比分割法及数学形态学方法对原始焊缝图像进行降噪和提取焊缝区域，并对提取的焊缝内部进行频域锐化的高频加强变换。

The witness also told the jury at the Royal Courts of Justice in London that he saw a paparazzo fighting with a member of the public who was trying to stop him taking pictures in the minutes before the emergency services arrived.

他还告诉在伦敦皇家法庭的陪审团，在急救服务到来之前，他当时看见一个狗仔队正和一群阻止他拍照的人打架。

The entire N／C program on a tape is made up of an accumulation of these successive data blocks.

纸带上的整个数控程序由这些连续数据单元连接而成。