查询词典 wave velocity

We analyzed the air gun signals in the 185Km-long seismic line. And the records showed that the air gun signal is full of seismic phase information. Based on these phases, we developed the P-wave velocity model for this area and find an obvious low-velocity layer, which is coherent to what people obtained from other geophysical methods in this area.

我们分析了气枪激发信号在长185km测线上的记录，拾取包含的丰富震相信息(如Pg，Pn，PmP等)，并在此基础上反演了该地区的P波速度模型，模型结果显示该地区存在明显的低速层，这与在该地区进行的其他地球物理探测结果一致。

Shear wave velocity is a parameter that geophysicists always want to obtain and is essential in AVO forward modelling. But at present there is no effective method to calculate shear velocity.

横波速度一直是地球物理学家非常希望得到的，也是AVO正演模拟必不可少的参数，而目前缺少具有理论基础的计算横波速度的方法。

In the paper, the velocity charactedstics of guided wave s along single interface and low-velocity lay-er in cross-hole seismic surveys are researched.

本文研究了井间地震勘探中单界面和低速层导波的速度特征。

Moreover, strong anisotropy is observed in the north and southcentral Tien Shan. Fast Pn velocity in the southcentral Tien Shan is nearly in NS directions, which is consistent with the SKS wave anisotropy concerning mantle flow. However, fast Pn velocity directions in the northcentral Tien Shan show a southward rotation variation. We estimate that it is probably related to the inserting of the crust of the Chu basin from the southern Kazakhstan platform to the central Tien Shan, which caused a change of stress fields and lithosphere deformation.

中天山北部和南部的各向异性也存在一定的差异，南部各向异性的快波方向为近南北方向，与SKS波的各向异性特征基本一致，反映了地幔物质的迁移方向；北部各向异性的快波方向呈向南凸出的旋转趋势，估计与哈萨克地台南缘楚河盆地地壳块体向天山挤入造成应力场的改变和岩石层变形有关。

The formation mechanism of the absolute instability and gyrotron backward wave oscillations is analyzed, and the methods to suppress the parasitical modes are discussed.The nonlinear theory model of gyro-TWT is consummated by considering the influence of tapered magnetic field and waveguide radius, electron velocity spread, and waveguide loss on electron beam-wave interaction. The large-signal characteristic of gyro-TWT, such as launching loss and absolute instability, are also analyzed in detail. This work establishes the foundation for the development of a gyro-TWT amplifier.

重点研究了两段损耗波导结构和损耗陶瓷结构回旋行波管中的电子注-波互作用，分析了绝对不稳定性和回旋返波振荡的形成机制和抑制寄生模式的方法；完善了回旋行波管的非线性理论模型，并考虑了磁场和波导半径渐变、速度零散、波导损耗等因素对注-波互作用的影响；详细分析了发射损耗、相位稳定性等回旋行波管的大信号特征，为回旋行波管放大器的研制奠定了基础。

In such a medium, the direction of the Poynting vector monochromatic plane wave is antiparallel to that of its phase velocity. Because of that, DNG displays some unusual electromagnetic properties such as backward-wave effect, negative refractive effect, perfect lens and a limit situation, zero index of refraction materials.

在这种材料中，单色均匀平面波的相速方向和坡印亭矢量方向是相反的，因此使双负材料表现出一系列反常的电磁特性如：回波效应、负折射效应、完美透镜效应和一种极限情况即零折射率材料等。

The velocities of ultrasonic wave and rock drillability are measured in perpendicular and parallel directions of the bedding plane of core samples which were cut from the approach hole of Chinese continental scientific drilling. Rock drillability index and P-wave velocity anisotropy coefficient are calculated from the testing data; and the results are discussed.

通过室内实验分别测定了岩芯垂直于和平行于地层层面方向的可钻性及声波速度，得到了岩石可钻性各向异性指数和波速各向异性系数，并对结果进行了讨论。

Because the temperature along the pipeline is not a constant, it changes the velocity of the negative-pressure-wave; the Romberg algorithm of numeric integral and the searching for algorithm are emloyed to locate the leakage.Multi-scale decomposition and reconstruction of wavelet transform is applied to filter the noise of negative-pressure-wave, which was brought by leakage. With the capacity to detect the signal singularity fast and accurately, wavelet transform was used to catch the break point of pressure signal. The work improved the accuracy of Δt in location formula, and the location accuracy is improved.

利用小波变换的多分辨分析和重构技术，对采集到的管道发生泄漏时产生的负压波信号进行了消噪处理；并利用小波变换技术对信号奇异点快速、准确的识别能力，对经过消噪处理后的负压波信号进行了奇异点捕捉，准确确定了定位公式中上、下游站点采集到的负压波奇异点的时间差△t，从而提高了定位的精度。

By using the similarity of wave crest to cylindrical lens ,a new method for measuring the velocity of liquid phase wave in the range of specified wavelengths was proposed, its applicational scope was determined by means of simulation evaluation,and meantime,this model was simulated in the lab.

探讨了低表面张力液体的表面波波速与波长的关系，利用该液体的单个波峰性质与圆柱透镜性质相似的特点，提出了一种新的在特定波长范围内测量该液体相速度的方法，并通过模拟计算确定了该测量方法的适用范围，同时在实验室模拟了该模型，实验结果表明在一定范围内该测量方法具有较高的精度。

And at the same time, through discussing the mechanism of earth wave absorbing tomography, it is known the CT of seismic absorption imaging method is better than the wave velocity imaging method in the identify ability of faultage crushed zone whose body structural plane is flabbiness and the dimensions is small.

阐述了地震波在粘弹性介质传播过程中具有的衰减特性，探讨了地震波吸收层析成像的机理，得知地震吸收CT成像方法，对岩体软弱结构面、裂隙和规模较小的断层破碎带的识别能力，要强于波速成像方法。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。