查询词典 periodic

Examplesof periodic sound sources are musical instruments, vowel sounds, the whistling wind and bird songs. Nonperiodic sound sources include unpitched percussion instruments, coughs and sneezes and rushing water.

乐器的演奏、元音、鸟鸣及风声都是周期性的声音，而打击乐器声、咳嗽声、喷嚏声以及流水声则是非周期性的。

Since the establishment of China , we have made great achievements in the economic construction . However , the economic development has followed an unsmooth way with periodic fluctuation .

自建国以来，我国经济建设取得了举世瞩目的伟大成就，但经济的发展也是在不断的周期波动中曲折前进的。

In the scheme,fixed channels are allocated to cells for exclusive use as nominal channels and reallocated after periodic time in terms of time-variant traffic distribution using ununiform compact pattern allocation algorithm.First available algorithm is used to assign dynamic channels .

在该方案中，固定信道采用非均匀压缩图案分配算法分配给各小区作为标称信道专用，并定期根据变化了的业务条件进行重新分配，动态信道的指派采用最先可行FA算法。

U.S. barge rates have been strong for the past two years for a shrinking fleet of barges, increased upbound movements of cargo and periodic unscheduled closures at lock and dam facilities or for low navigation problems related to low or high water conditions.

由于驳船数量不断减少、北向货运有所增加、船闸大坝不定期关闭以及水位状况致使通航率低等问题，美国驳船运价在过去两年里保持强劲势头。

Numerical calculation of the unsteady flow within turbomachinery The periodic unsteady flow within impeller/vaneless diffuser or impeller/vaned diffuser was numerical simulated in this thesis. The simulation was calculated on the CFX software flat.

离心风机内部非定常流动的数值模拟本文对叶轮/无叶扩压器和叶轮/有叶扩压器两种结构形式的离心风机内部流动进行了全流场非定常流动数值模拟。

However, the effect from impeller did not keep to the outlet of the vaneless diffuser. Through analyzing the periodic mean field, an unsteady effect region was found within the region whose biggest radius ratio was less than 1. 2 in the vaneless diffuser. The unsteady flow at three flow rate conditions had the similar unsteady characteristic.

无叶扩压器内近前盘r-6面上锁相平均流场的分析表明，当叶轮处于不同周向位置时，无叶扩压器内的流动表现出非定常流动特性，尤其是在人口区域非定常流动特性更为明显。

For fluid system with periodic boundary conditions, it is proved that virial theorem does not hold, and neither the calculation method based on that theorem.

为了计算分子动力学系统中压力的分布，考察了文献中报导的压力算法。

The intensity ratio of TO and LO inMCT was observed to be different. Such difference was explained in terms of the different Ramangeometry arrangement.〓. The laser-induced micro-photoluminescence in the range of 1000～5000〓(1.34eV～1.83eV) was found for the first time in LPE MCT epilayer. The center of photoluminescence wasat 2750〓 or 1.62eV and the FWHM of luminescence was 2000〓 or 0.25eV. We assume thatthe photoluminescence is due to recombination of electron from an anion vacancy resonance levelto the top of valance. In addition, new Raman shift was observed at 750〓 in LPE MCTepitaxial film.〓. The laser-induced micro-photoluminescence with quasi-periodic structure was observed forthe first time at room temperature in one of MOVPE MCT epitaxial film samples. The range offluorescence was from 1.46eV to 2.21eV, i.e., 1.73eV above the conduction band edge.

2首次在LPE生长的碲镉汞外延薄膜的显微Raman谱中，在1000～5000〓范围发现了激光激发显微荧光，该荧光的发光范围换算为电子伏特标度为1.34eV～1.83eV，荧光的发光中心大约位于2750〓，即1.62eV，发光的半峰高宽约为2000〓或0.25eV；指出该显微荧光来源于碲镉汞薄膜中的阴性离子空位共振能级的激光激发发光；观察到了碲镉汞外延薄膜中一个新的Raman散射峰，位于750〓位置； 3首次在一块用MOVPE方法生长的〓Te外延薄膜的显微Raman谱中，发现了1.46eV至2.21eV范围并伴随有周期结构的显微荧光峰，该发光峰对应的能带中心位于〓Te材料导带底上方1.73eV，通过研究得出样品在1.46eV至2.21eV范围的显微荧光峰是由于改进 MOCVD 生长工艺，提高了碲镉汞外延薄膜的结构质量所致；通过分析指出该显微荧光来源于外延层中的阴性离子空位的共振能级发光。

About four out of five people with RLS also experience periodic limb movements during sleep, according to Winkelman.

Winkelman指出，大约五分之四的RLS患者在睡觉时会有周期性的肢体运动。

Periodic limb movements -- jerking or twitching of the legs or feet -- occur in a fairly set pattern, with a still period in between."It almost looks as if they're guided by a metronome," said Winkelman.

周期性的肢体运动——腿或脚以一种设置好的程序摇动或抽搐，运动之间有一个平静阶段，似乎他们受到节拍器的指导。

Where's the switch I could just turn off and on,this ain't what I chose to be

开关在哪里我要控制它，这不是我的结局

A start-up called Unvarnished has begun a site where people can post anonymous reviews of your work on your social-networking account.

一家名为Unvarnished的新公司开始了一个人们可以藉由自己的社交网路帐号发表对於己身工作情况的匿名评语网站。