查询词典 longitudinal wave

Gravity wave and ozone are two interesting topics in the middle and upper atmosphere. In this dissertation, they are studied by numerical simulation and instrument development respectively.In section one, by using FICE scheme and TIME-GCM, a model of trace gases and OH airglow affected by gravity wave is set up, then the propagation of nonlinear gravity wave and the effect on trace gases and OH airglow are analyzed. The result shows gravity wave excited by tropospause forcing can propagate stably to the mesosphere through the stratosphere so that energy and momentum can be transferred from one region to another. In this process, gravity wave undergoes growth, overturning, convection and breaking. And the no-isothermal structure can accelerate the breaking of gravity wave in mesospause, and the breaking of gravity wave is an important source of convection and small-scale waves.

中文题名气辉的非线性重力波研究及臭氧总量探测仪的研制副题名外文题名 The study of airglow by nonlinear gravity wave and the development of the total ozone spectrometer 论文作者王咏梅导师刘振兴王英鉴学科专业空间物理学研究领域\研究方向学位级别博士学位授予单位中国科学院空间科学与应用研究中心学位授予日期2003 论文页码总数88页关键词臭氧气辉重力波馆藏号BSLW /2003 /P421 /7 重力波和臭氧是中高层大气中研究的两大热门课题，本文分别从理论模式和仪器研制两方面对它们进行了研究。

The numerical results of stationary and transient Green'sfunction for high-velocity surface-head wave on some selected crystals are comparedThrough the above analyse,it is indicate that the first arrival wave mode is thelongitudinal-wave head-wave,and its propagate velocity is equal to the groupvelocity of the longitudinal bulk wave alone the surface.Furthermore,this modedoes not have the Δv/v effect,i.e.,its velocity is the same no matter the surface isfree or metalized.

通过对表面激发的瞬态和稳态Green理论分析和数值计算，表明在压电晶体表面上实际上看到的最高速的最先到达的波动模式是纵波头波，它具有沿表面纵波的群速度，而且对压电晶体，它不具有Δv/v效应，即在自由表面和金属化表面其传播速度是一样的，而压电晶体表面波及伪表面波均存在Δv/v效应。

The solitary wave can be generated considering Goring and Raichlen's movement of a paddle. The proposed original linear solution for the solitary wave generation is expressed in the hypergeometric function. Two disadvantages of the original solution with large trailing wave and skewed wave profile are found by comparing with the theory of solitary wave derived from Boussinesq's equation. The difference between the original linear solution and the solitary wave theory results from the nonlinearity and dispersion of generated waves in the flume.

本文并以弱非线性的孤立波造波问题做为解析之对象，由於孤立波造波板速度为一超越函数，造成解析上的困难；本文以 hypergeometric 函数推求常微分方程式之全解，并与理论波形解比较后，发现由於未考虑非线性及分散性过强等问题，使得线性暂态解较理论波形拉长与歪斜，可能无法有效描述孤立波造波问题，故针对线性之分散关系做出修正。

The caculation results of Pubugou high rockfill dam under the action of design earthquake travclling wave show: in few cases, the seismic response under travelling wave input is less than that under routine input; but in many cases, the former surpasses the latter, and the rate of increase of few components has doubled and redoubled; the strengthened areas of seismic response under the action of travclling wave are in the direction which travelling wave has gone; compared with acceleration and displacement, dynamic stress is even more sensitive to travelling wave input; compared with the direction along river, the effects of travelling wave in the direction cross river are even more intense.

结合瀑布沟高土石坝在设计地震行波输入下的研究表明，行波反应少数情况下弱于常规反应，而大多数情况下则有所增强，个别指标甚至有成倍的增加；行波反应强化区均出现在去波向；与加速度和位移相比，动应力反应对行波输入更为敏感；与坝体顺河向行波效应相比，横河向则更加强化。

By measuring the velocities of the P-wave and S-wave in three orthotropic directions including parallel and vertical directions to the stratum of the rock samples for slate, phyllite, mylonite and metasandstone, and based on the wave velocities of other rocks from the relevant studies, the anisotropic effect of wave velocity ratio of the P-wave and S-wave for most rocks is put forward.

通过对板岩、千枚岩、糜棱岩和变质砂岩等4种各向异性岩石在平行和垂直层理或板理的3个正交方向上进行大量的纵、横波波速试验，并结合对相关文献中己有岩石波速数据的深入分析，提出岩石介质纵、横波波速比的各向异性效应。这种效应广泛存在，其发育程度受到岩石类别的控制。

And by applying the linear dispersion relation of wave, all the properties of wave refraction including wave rays, constant phase lines, phase function and crest lines etc., can be expressed in explicit functions. By introducing an orthogonal curvilinear coordinate along the wave ray and the constant phase line, and with an estimated scale factor, the refraction coefficients along any wave ray can then be determined. The present results are verified by ordinary wave ray theory and some previous numerical results.

就此特例情况在波浪的线性分散关係的应用下，前进波浪折射现象的整体特性，包括波向线、等位相线、位相函数与波峰线皆被导述出明確显然的函数表示；同时引入由沿著波向线与等位相线所构成的完全符合波浪折射几何通性的正交曲线座標，求出其尺度因子后，由能通量守衡原则定出沿著任一条波向线上的折射係数；並由之对往昔纯依两相邻的波向线间的几何类比所给定的折射係数给予导証之。

Based on the research of torsional wave and flexural wave of the transmission shaft , this paper obtained expression of theirs on the sine wave , the cosine wave , the exponential decrease wave , the exponential decrease seiche wave .

针对急剧冲击和大范围转动的特点，将圆柱体转动能量传输信息模型扩展建立在相对论基础上，建立了相对论性转动能量传输信息模型及其在不同坐标系下的转换模型。

In order to probe the absorb coefficients of earth medium by the direct wave, reflected wave and transmied wave amplititude which are picked up from the radar wave racords yielded by finite element method,the paper gives out the attenuated radar wave equations in time domain and the attenuated radar wave differential equations while the motion changes simple harmonic with time and electric parametets change slowly with space.

摘 要 为了用有限元方法生成雷波正演记录，从而拾取直达波、反射波、透射波振幅信息，以确定介质吸收系数，文章在时间域给出了雷达波含衰减项的波动方程，及在运动随时间简谐变化以及电性参数随空间缓变的条件含衰减项的雷达波遵循的简化微分方程。

The shoaling wave height is related to wave steepness. Comparing with wave theories the shoaling coefficient of small amplitude wave theory_ which is not related to wave steepness, disagrees with experimental reset. The experimental result has the trend with Stokes third order shoaling theory, but Stokes wave theory overestimates the shoaling coefficient .

波浪之浅化波高与波浪尖锐度有关，微小振幅波理论中浅化波高与波浪尖锐度无关与实测值不符，实验结果在定性上与Stokes波三阶浅化理论有相同之趋势，但在定量上实验之浅化系数较小，理论值有高估的现象。

The earliest change of ERG in birdshot chorioretinopathy was the prolongation of cone ERG implicit time. Followed by the decrease of dark-adapted b wave amplitude. The b wave amplitude of cone ERG decreased later. The duration of the disease correlates with the amplitude of b wave in the same patient. The a wave was the last affected and the decrease of the a wave amplitude was disproportionate compared to that of b wave, revealing a typical negative type ERG.

结果发现最早的变化为锥细胞ERG潜伏期的延长；接着是暗适应b波振幅下降，锥细胞b波下降较晚，同一患者病程的长短和ERG b波振幅下降幅度一致；a波振幅下降晚于b波，且下降不成比例，出现负相ERG，可作为诊断此疾病的特征性ERG。

It's bell can reach over a meter in diameter.

它的身体最大可以达到直径1米多。

Now they are overdue and I shall have to pay a fine.

现在他们过期了，我不得不付罚款。