查询词典 wave velocity

Therefore the dispersion curves obtained in the field are primarily consisted of the first mode. For a heterogeneous elastic solid consisting of three homogeneous layers whose interlayer has low velocity, the phase velocity V〓 of the first mode will also close up to the Rayleigh wave velocity of the bottom layer when frequency f→OHz, but V〓 of the first mode will close up to the shear wave velocity of the interlayer when f→∞, and there is a cut-off frequency at high frequency region for the first mode and V〓 close up to the compressional velocity of interlayer when interlayer is liquid.

当三层固体介质中存在软夹层时，若f→OHz，则其基阶模式的相速度V〓→V〓（V〓为最底层介质的瑞利波速度）；若f→∞，其基阶模式V〓→V〓（V〓为中间层介质的横波速度）；若三层介质中存在液体夹层，当f→OHz时，基阶模式V〓→V〓，而基阶模式在高频段存在一个截止频率，截止频率处的瑞利波速度V〓→V〓；由此可判定，野外实测的相速度频散曲线不仅有基阶导波模式，同时还应有高阶导波模式波的存在，接收信号中存在模式间的跳跃，因此频散曲线会产生"之"字形现象。

Meanwhile, 2-D spectrum and the corresponding parameters of irregular wave transformation (predominant wave direction and mean wave direction, peak frequency and peak spectrum density, spectrum width, mean period, mean wave length, mean wave crest length and 3-D index and so on)、 1-D frequency spectrum and the corresponding parameters and numerical results of wave height、 wave direction of regular wave transformation are offered.

提供不规则波传播变形二维谱及其谱参数(主波向及平均波向、峰频及谱峰值、谱宽度、平均周期、平均波长、平均波峰长度及三维性指标等等)，不规则波一维频率谱及其谱参数和规则波变形的波高、波向模拟值。

Chapter 2 is devoted to study of exact solutions of the nonlinear evolution equations. Using solutions of a Bernoulli equation instead of tanh in tanh-function method we find some more general solutions of the KdV-Burgers-Kuramoto equation , and by using the nonlinear telegraph equation we show that there are many different choices on its balancing number m and the power n of the nonlinear term in Bernoulli equation by which we can recover the previously known solutions and also can derive new square root type solitary wave solutions. Exact solitary wave solutions for a surface wave equation are obtained by means of the homogeneous balance method. We also present an approach for constructing the solitary wave solutions and non-solitary wave solutions of the nonlinear evolution equations by using the homogeneous balance method directly, which is also used to find the steady state solutions, solitary wave solutions and the non-solitary wave solutions of the 2+1 dimensional dispersive long wave equations. The soliton-like solutions of the BLMP equation and the 2+1 dimensional breaking soliton equation are found by use of the symbolic-computation-based Method.

第二章中研究了非线性发展方程的精确解：用双曲正切函数法中的双曲正切函数换为Bernoulli方程的解的方法而给出KdV-Burgers-Kuramoto方程的精确解并用非线性电波方程为例说明了平衡数m和Bernoulli方程中非线性项的次数n有着多种选择的可能，它不但使我们能找到已知解而且也能找出新的根式孤立波解；用齐次平衡法给出一个曲面波方程的精确孤立波解，并提出直接用齐次平衡法寻找非线性发展方程的孤立波解、非孤立波解的方法，作为应用给出2+1维色散长波方程组等的定态解、孤立波解、非孤立波解等；用Symbolic-computation-basedMethod获得BLMP方程和2+1维破裂孤子方程的类孤子解；提出sine-Gordon型方程的直接求解方法，并获得sine-Gordon方程、双sine-Gordon方程、sinh-Gordon方程、MKdV-sine-Gordon方程和Born-Infeld方程等的精确孤立波解。

This problem is also important and valuable in Nonlinear Optics. It will be very helpful to understand how the aberrations affect the course of three- wave mixing, such as the change of conversion efficiency, the distribution of intensity and phase.Small signal solution of aberrated second harmonic generation is deduced from three-dimension three wave coupling functions. The numerical work gives out lot of results of different aberrations. The effects of the fundamental waves aberrations, which will change the conversion efficiency, distribution of intensity and phase in the frequency conversion, is analyzed. It shows that when walk-off and diffraction effects could be ignored approximately estimation of the phase distribution of second-harmonic wave could be done. The far field divergent angle and second moment radius of harmonic wave will vary with the aberration of fundamental wave, but the far field divergent angle will be obviously smaller than that of fundamental wave. The phase distribution of both fundamental and harmonic wave is measured using Hartmann-Shack wave front sensor in the experiment with 1064nm and 790nm lasers, respectively. Results are given.

首次从三维三波相互作用方程组推导得到了位相畸变光束倍频的小信号解；通过建立国防科学技术人学研究生院学位论文三维数值模型，编写相应仿真程序，首次得到了位相畸变光束倍频过程的大量计算结果，深入细致地研究了位相畸变光束经非线性光学频率变换后谐波的转换效率、光强分布、位相分布以及影响它们的各种因素；得出谐波的远场发散角和光斑二阶矩的变化规律会因为基波像差的不同而不同，但谐波的远场发散角明显地比相应基波的小的结论；得到了在走离效应和衍射效应等影响许多因素可以忽略的情况下，位相畸变传递到二次谐波的估算式；举例分析了KDP三倍频方案中，基波位相畸变对二次谐波和三次谐波的影响；实验工作中，用哈特曼一夏克传感器分别对IO64nm倍频过程和790飞秒超短脉冲倍频过程中的基波和谐波的位相分布进行了测量，给出了相应结果。

Small signal solution of aberrated second harmonic generation is deduced from three-dimension three wave coupling functions. The numerical work gives out lot of results of different aberrations. The effects of the fundamental wave's aberrations, which will change the conversion efficiency, distribution of intensity and phase in the frequency conversion, is analyzed. It shows that when walk-off and diffraction effects could be ignored approximately estimation of the phase distribution of second-harmonic wave could be done. The far field divergent angle and second moment radius of harmonic wave will vary with the aberration of fundamental wave, but the far field divergent angle will be obviously smaller than that of fundamental wave. The phase distribution of both fundamental and harmonic wave is measured using Hartmann-Shack wave front sensor in the experiment with 1064nm and 790nm lasers, respectively. Results are given.

首次从三维三波相互作用方程组推导得到了位相畸变光束倍频的小信号解；通过建立三维数值模型，编写相应仿真程序，首次得到了位相畸变光束倍频过程的大量计算结果，深入细致地研究了位相畸变光束经非线性光学频率变换后谐波的转换效率、光强分布、位相分布以及影响它们的各种因素；得出谐波的远场发散角和光斑二阶矩的变化规律会因为基波像差的不同而不同，但谐波的远场发散角明显地比相应基波的小的结论；得到了在走离效应和衍射效应等影响许多因素可以忽略的情况下，位相畸变传递到二次谐波的估算式；举例分析了KDP三倍频方案中，基波位相畸变对二次谐波和三次谐波的影响；实验工作中，用哈特曼-夏克传感器分别对1064nm倍频过程和790飞秒超短脉冲倍频过程中的基波和谐波的位相分布进行了测量，给出了相应结果。

For a heterogeneous elastic solid consisting of two homogeneous layers, three homogeneous layers whose shear wave velocities increasing with depth, or three homogeneous layers whose interlayer has high velocity, if there are multi-mode dispersion curves, the phase velocity V〓 of the first mode will close up to the Rayleigh wave velocity of the bottom layer when frequency f→OHz, and V〓 of the first mode will close up to the Rayleigh wave velocity of the top layer when f→∞.

由多导波模式的相速度频散曲线还可知，对于二层固体介质、结构层的横波速度随深度而递增的三层固体介质、含硬夹层的三层固体介质而言，若频率f→OHz，其基阶模式的瑞利波相速度V〓→V〓（V〓为最底层介质的瑞利波速度）；若f→∞，其基阶模式的V〓→V〓（V〓为最上层介质的瑞利波速度）；因此，随着频率f逐渐升高，野外实测的瑞利波相速度V〓曲线应该主要为基阶导波模式。

The study covers the vertical displacement distribution character of each mode of Rayleigh wave, theoretical dispersion curve character of multi-modes Rayleigh wave and the characters of the max-mode Rayleigh wave dispersion curve in different layers structure, which are velocity increasing with deep, high velocity layer within underground, low velocity layers within undergroan and high velocity surface layer, within the depth of 15 meters.

研究了地层速度随深度递增型、地层中有硬层或软夹层型、表层为高速的公路型等4种地层结构在15m深度内，瑞利面波各阶模态的位移幅度分布特征、多阶模态面波的理论频散曲线特征以及不同地层结构上的&最大模&面波频散曲线的特征。

Based on the item of national high technology development project, the thesis studies the reasonable construction pattern of the tunnel portal, incidence of the micro-pressure wave and the the effect of bell-mouthed hood, lacunaris hood and expansile hood on alleviating the micro-pressure wave in the situations of single line and double line, obtains the relationship between the max micro-pressure wave and the velocity of the train as well as the relationship between the max micro-pressure wave and distance of measuring point at the velocity of 100km/h-550km/h, compares the different alleviative effect of the three different hood to max micro-pressure wave and finally proposes the reasonable construction pattern of the tunnel portal.

本文针对国家高技术研究发展计划(863计划)课题"磁浮交通沪杭线越黄浦江隧道的工程技术问题研究"，在单洞单线和单洞双线两种工况下，对隧道洞口的合理结构形式和影响范围，以及洞口喇叭形入口缓冲段、多孔壁入口缓冲段以及隧道出口膨胀室对减缓微压波的作用进行了研究，得到了磁浮列车速度在100km/h～550km/h时隧道出口微压波最大值与速度的关系以及微压波最大值与测点距离的关系，比较了三种不同形式缓冲结构对微压波最大值的减缓效果，提出了隧道洞口的合理结构形式。

The lift-off angle of saltating sand grain follows LogNorm4 function distribution; lift-off horizontal velocity, vertical velocity and resultant velocity of saltating sand grain and falling angle and vertical velocity of saltating sand grain follow Gamma function distribution; falling horizontal velocity and resultant velocity of saltating sand grain follow Pearson IV function distribution.

跃移沙粒起跳、降落速度分布函数利用风洞实验获得的沙粒跃移运动的片断轨迹，反推出沙粒起跳角度服从LogNorm4函数分布，跃移沙粒起跳水平、垂直及合成速度均服从Gamma函数分布。

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。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。