查询词典 wave velocity

Arteriosclerosis has a huge influence on human's health. Currently the diagnosis of arteriosclerosis is based on invasive cardiac catheter measurement, but this method could cause subject's great inconvenience and might be dangerous. In this regard, this paper proposes a non-invasive pulse characteristic points locating system for arteriosclerotic degree examination. The pulse characteristic points we use include pacemaker, percussion wave peak, dicrotic notch and dicrotic wave peak. From the pulse characteristic points, we can calculate the arteriosclerotic degree examination parameters, such as pulse wave velocity, stiffness index and reflection index, etc. Those parameters can be used for diagnosing the degree of arteriosclerosis.

动脉硬化对於人体健康有极大的影响，然而目前动脉硬化的诊断主要在於侵入式的心导管量测，容易造成受测者的诸多不便及危险性；有鉴於此，本论文系设计一应用於动脉硬化程度检测之脉波特徵点定位系统，如：起搏点、主波峰顶点、重搏切迹与重搏波顶点等，经由准确的脉波特徵点定位计算出脉波传导速率、硬化指数与反弹指数等动脉硬化程度检测参数，透过这些数据，可提供医师在诊断动脉硬化程度上的辅助。

For pass through the low velocity zone,the S wave of earthquakes with epicentral distance of 9°~36° are weak,so the LG wave are used to determine the epicentral distance of the earthquake in shadow area of S wave.

由于来自震中距9°～36°的地震经过了低速层，造成了S波不发育。

The results show that when gravity wave's propagating in the homogenous winds, the nonlinearity is stronger in the fair wind than in the contrary wind, the background winds change the propagation velocity and path, and when gravity wave's propagating in the homogenous winds, the vertical wavelength decreases, the average upgoing energy flux reduces which implies the ambient winds absorb the energy of the wave, realizes coupling of the different atmosphere layers.

结果表明，当重力波在均匀风场中传播时，非线性效应在顺风场中比在逆风场中更显著，背景风会改变重力波在水平方向的传播速度和传播路径；当重力波在剪切风场中传播时，重力波在垂直方向上平均能流随高度的增高而减少，表明背景吸收了重力波的能量，在重力波向上传播的过程中，实现了大气各层之间的耦合。

The results of computation show that this method is very effective for reducing and controlling the transverse oscillation of wave motion and for the calculation of wave particle velocity of wave motion on free surface, w...

计算表明：这种0—1混合型边界元的剖分方式，在控制和减缓波浪&横向振动&幅度及水面单元水质点波动速度的计算方面，显示出了其独到的优越和灵活之处，为时域内的波浪非线性变形计算提供了时步上的数值保证

When the velocity proportion of longitudinal wave to transverse wave of a bed is distinctly different from that of another bed, the reflection factor will be changed with the variation of incident angle according to the elastic wave mechanics, which is the foundation of AVO theory.

由弹性波动力学理论可知，当一种岩层纵、横波速度与另一种岩层纵、横波速度之比明显不同时，反射系数随入射角的变化而变化。

In the process of building and using the mass concrete structures, because of the effect of out-side condition and themselves, some faults will form in the structure, these faults will effect the bearing capability and endurance Using nondestructive testing method to test the concrete"s quality and diagnose its healthy, which has the significant sense in assessing the safety stability and research of the administering diseasesThis dissertation mostly researched the testing methods in the mass concrete structure, discussed the principles, methods, features, sphere of application of the ultrasonic testing in the mass concrete structure with faults, used dynamic FEM to simulate the testing process, discussed when the concrete structure with cracks is under the effect of the pulse, how the elastic waves propagate and what are their changing feature, Researched the principles of the first-arriving waves" phase when the cracks" depths are not same, obtained the relation between the inversion point and the cracks" depth, which has the direction sense in the application of projects,The second part of this dissertation is CT , which used the ultrasonic wave running through the tested-substance to get arriving-time of the ultrasonic wave, then inverse the image This dissertation drawed one CT program which can well present the different little cells ultrasonic wave velocity profiles of the substance, thereby to diagnose the quality of the part of the tested-substance, CT has the better using foreground..

在混凝土结构的施工及使用过程中，由于受其自身及外界各种因素的影响，常常会产生一些缺陷，对结构物的承载能力和耐久性造成严重影响，采用无损检测技术进行质量检测和健康诊断，这对混凝土结构开展安全、稳定性评估以及病害隐患治理研究具有重要意义。本论文主要针对大体积混凝土结构缺陷的检测方法展开研究工作，重点讨论了超声波法检测混凝土结构裂缝的基本原理和方法及其特点、适用范围，运用动力有限元数值模拟其检测过程，探讨了有裂缝缺陷的混凝土结构在脉冲荷载作用下弹性波的传播及其变化特征，研究了不同裂缝深度下首波相位变化规律，得出了反转临界点与裂缝深度之间的关系，这对实际工程应用具有指导意义。声波CT是一种新的无损检测技术，它是利用声波穿透被检测体获取声波接收时间，来进行计算机反演成像的技术。本文利用直射线法编制了层析成像程序，能较好地呈现被检测物体各微小单元的声波速度分布图像，从而对检测体的质量状况作出诊断评估，具有较好的应用发展前景。

The frequency-dependent sensitivity coefficients with respect to the parameters of the radial layers are computed quantitatively. Comparing the horizontal permeability with the vertical permeability, the horizontal mobility plays the predominant role over the entire frequency range. The Stoneley wave is more sensitive to the velocity of the horizontally propagating SH wave than the flexural wave.

利用灵敏度曲线定量研究了不同频率下地层各个参数对相速度和衰减系数的贡献大小，主要结果显示模式波的衰减受水平渗透率影响明显，而垂直渗透率的变化对模式波几乎无影响；斯通利波对水平向传播的横波速度比弯曲波的灵敏度高。

Secondly, the direct demodulation detection system of 8mm wave band 32-channel on the background of millimeter-wave focal plane imaging is built, according to millimeter-wave passive detection theory, at the same time, the principle experiment is carried out, and the basic theory of millimeter-wave detection are confirmed.

其次，根据被动毫米波探测理论搭建了以毫米波焦平面成像为应用背景的8mm波段32通道直接检波式探测系统，并进行了原理性实验，验证了被动毫米波探测的基本理论。

The stable wave-field propagators of one-way wave equation for Born and Rytov approximations are derived by using the local Born and local Rytov approximation methods in the scatter theory of wave-field propagation, and their application effects in prestack depth migration imaging of wave equation are compared theor...

利用波场传播散射理论中的局部Born近似和局部Rytov近似，分别导出了单程波方程的稳定的Born近似波场传播算子和稳定的Rytov近似波场传播算子，然后从理论和实践上比较了它们在地震数据波动方程叠前深度偏移成像中的应用效果。

Wave protection effects of circular arc wave walls and paraboilc wave walls are compared and analyzed,showing that curving wave walls are very effective in preventing overtopping .

文章中就圆弧型及抛物型曲面挡浪墙的防浪效果进行了对比，说明曲线防浪墙对阻止越浪是十分有效的。

"Yes, now you can give yourself airs," she said, you have got what you wanted.

"对了，您现在高兴了，"她说道，这是您所期待的。

Then the LORD said to me: Rebel Israel is inwardly more just than traitorous Judah.

上主于是对我说：＂失节的以色列比失信的犹大，更显得正义。