群速度

The maps at short periods reveal an evident lateral heterogeneity in the curst of North-China, quite well in agreement with known geological and tectonic features.

四、将研究区域划分为0.25°×0.25°的网格，用面波层析成像方法，反演得到了4s-40s周期的群速度分布图像。

The effects of group velocity dispersion on nonlinear optical loop mirror OTDM demultiplexer are analyzed theoretically and numerically in this paper.

本文就群速度色散对非线性光纤环镜型OTDM解复用器的影响进行了理论与数值分析。

Concepts of group velocity and dispersion in electrodynamics course are discussed in this paper.

讨论了电动力学教学过程有关群速度及色散的概念。

The GKS stability theorem for one-dimensional model of hyperbolic initial and boundary value problem, Trefethen's explanation and extension based on the concept of group velocity are generalized firstly. Another possible high-frequency instability mechanism in numerical realization of MTF is pointed out based on his explanation and extension, namely, coupling effect of outgoing harmonic wave along one direction and node motion in the other directions can reverse the energy propagation in multi-dimensional discrete grids.

本文概述了—维双曲型偏微分方程组初边值问题数值稳定性的GKS定理及Trefethen基于群速度概念对这一定理的解释和推广；并应用Trefethen的解释和推广指出了MTF在数值实现中可能出现的另一种高频失稳机制，即在多维离散网格中，沿某一空间方向的外行简谐波，由于与其他空间方向节点运动的耦合效应可以使能量传播方向反向。

The function relation of pulse group velocity with frequency and rain rate is obtained.

分析了脉冲波展宽效应机理，得到脉冲波群速度与电波频率、降雨率的函数关系。

Meanwhile group velocity is negative in the presence of the band gap range.

同时在禁带出现的区域群速度为负值。

Our results suggest that the negative group velocity does exist different formation with band gap range.

我们的结果表明群速度的负值的确存在于有序介质中的禁带区域内。

The group velocity dispersion properties of photonic crystal fiber were investigated in detail by equivalent index model.

应用等效折射率模型对折射率导模光子晶体光纤的群速度色散特性进行了详细的讨论。

It is shown that an increase of intensity will lead to strengthen the effect of group velocity dispersion.

并且指出，增加脉冲能量会导致群速度色散效应增强。

The group velocity is estimated as 1/35 of the light speed in vacuum.

群速度估计为真空光速的1/35。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。