查询词典 periodicity of function

The bulk of solid-state physics theory and research is focused on crystals , largely because the periodicity of atoms in a crystal — its defining characteristic —facilitates mathematical modeling, and also because crystalline materials often have electrical , magnetic , optical , or mechanical properties that can be exploited for engineering purposes.

固体的内部结构和运动形式很复杂，这方面的研究是从晶体开始的，因为晶体的内部结构简单，而且具有明显的规律性，较易研究。以后进一步研究一切处于凝聚状态的物体的内部结构、内部运动以及它们和宏观物理性质的关系。这类研究统称为凝聚态物理学。

Since Bloch's Theorem applies only to periodic potentials, and since unceasing random movements of atoms in a crystal disrupt periodicity, Bloch's Theorem is only an approximation, but it has proven to be a tremendously valuable approximation, without which most solid-state physics analysis would be intractable.

由于布洛赫定理仅对周期性势场的情况严格成立，而由于实际的晶体中不可避免的有各种缺陷或者原子相对于平衡位置的位移，所以布洛赫定理对于实际晶体来说只是一个近似。但是布洛赫定理对于固体物理的研究不可或缺。

Because the speech signal is periodicity at sonant which vocal cords surge in low frequency and similarity to white noises at surd , the pitch can be detected in traditional way through the correlation operation without the speech produce model

在人类语音的浊音段，声带发生较低频率的振荡，语音信号呈明显的准周期性，而在清音段，语音信号则类似于白噪声。

It means to recognize periodicity by analyzing the spectral density of periodically variable sequence, then to judge the measured period true or false through the statistical examination of Fisher's Kappa and Bartlett's Kolmogorovsmirnov.

第三节"波动周期的模型测定法"以"收入—支出"结构和"需求导向"为基本构架，通过建立中国宏观经济波动模型来测定宏观经济内生变量波动的周期长度，这种通过解析思路测定经济变量波动周期的方法，具有理论支撑，其科学性、可信性是显而易见的。

The daily variation of the telluric field E had per 9 periodicity, and the amplitUde |E| showed abnormal changes.

大地电场E具有日变倍9周期性和振幅|E|变化特征；4。

We find that external noise can destroy the periodicity of the transient current and cancel the long-time average current peaks.

我们发现噪声可以破坏瞬时电流的周期性并削减长时平均电流的峰值。

The cycle undulatory theory tell us that there is certain periodicity in economical development. This kind of periodic performance almost simultaneously expands for the many economic activity, then universal declines, contracts and recovers, thus influend economy development.

周期波动理论认为经济发展存在周期性，这种周期性表现为很多经济活动差不多同时扩张、继之以普遍的衰退、收缩与复苏，从而影响经济的发展；而景气理论则是在周期波动理论的基础上，构建景气指数来监测宏观经济受经济周期波动的影响。

With the improvement of the structural complication and strength index of the engine structure, during the work process, the bending-shaft produce bent and torsion because of the action of periodicity variational air pressure, inertia pressure evocabled by the to-and-fro and whirligig motion and torque, therefore, engine bending-shaft must be provided with the preferable fatigue intensity and the structure rigidity through making use of the material of high intensity and the reasonable forging technique.

随着发动机结构的复杂化和强化指标的不断提高，曲轴在工作过程中，由于受到周期性变化的气压力、往复和旋转运动引起的惯性力以及弯矩、扭矩的共同作用，既产生弯曲又出现扭转，这就要求发动机曲轴具有高的疲劳强度和结构刚度。

By analyzing periodicity of α-helices and β-strands, sequences of aminophenol are transformed into sequences of hydrophobic values and process it by wavelet analysis and Fourier transform so that Power Spectrum Density was gained.

本文在分析了α螺旋和β折叠的周期性基础上，将氨基酸序列映射为疏水值序列并对其进行小波分析然后再做傅立叶变换从而得到平均功率谱图。

Large scale structure of universe, bolometric flux, luminosity distance, quasars, galaxies, redshift space, redshift periodicity.

宇宙大尺度结构，谱视亮度，光度距离，类星体，星系，红移空间，红移的周期性。

We are forbidden from giving money to these shoeless, skinny children, as this will perpetuate begging.

向光着脚，骨瘦如柴的孩子施舍是不可以的，因为要招来无休无止的乞讨。

It would be hard not to fall victim to some sharpeyed policeman.

要想不被某个目光锐利的警察抓到，谈何容易。