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- Fatal accidents have decreased in frequency over recent years. 近年来死亡事故发生的频率已经下降。
- Impact in power frequency variation. 频率变化之影响。
- The VCO presented in this paper has a tunable frequency over 290-470 MHz under control voltage from 1V to 5V, with an output power of 2.20-2.30dBm. 锁相环中的VCO采用了差分对结构的LC压控振荡器结构;在1V到5V的控制电压下能产生290到470的可调频率;输出功率为2.;20到2
- Fatal road accidents have decreased in frequency over recent years. 近年来致命交通事故发生率已经下降。
- Contrail Frequency over the United States from Surface Observations. 地面观测得到的美国飞行云发生的频率。
- The disconnector shall operator at the power frequency short circuit while MOA's failure under the abnormal conditions. 避雷器带脱离的目的是当避雷器在异常情况下发生故障损坏时，工频短路电流使脱离器工作，脱离器接地端自动脱开，使故障的避雷器与系统脱离，并表明故障避雷器更换。
- The vibration is varied in frequency over a range on the order of 5 to 2,00 0 cps, usually at a constant octave. 振动的频率在5到2000赫的范围内变化，通常用一常值的八阶变化率。
- A review on the study on power frequency electromagnetic field hazards to organisms. 工频电磁场生理危害的研究进展。
- The vibration is varied in frequency over a range on the order of 5 to 2, 000 cps, usually at a constant octave. 振动的频率在5到2000赫的范围内变化,通常用一常值的八阶变化率。
- The New Techniques Development of High Voltage High Power Frequency Converter of ABB Co. ABB高压大功率变频器的最新技术发展
- When the frequency changer has malfunction, power frequency is adopted, and the motor speed is nonadjustable. 万一变频器出现故障时，可工频驱动，转速不可调。
- It is pointed out that the power frequency electromagnetic field is inductive field,but not radiation field. 对输变电工程工频电磁场、无线电干扰进行了理论分析,指出输变电工程工频电磁场是感应场,而非辐射场。
- The frequency ranges of eddy contributions to CO2 fluxes were mostly within 0.01-2.0 Hz,and the eddy translated by low frequency over canopy contributed more of CO2 fluxes. 湍流通量贡献区主要在0.;01~2Hz频率范围内;冠层上方低频传输的湍涡贡献了更多的CO2通量
- The average EEG(AEEG) increased while the average mean power frequency (MPF) and comprexity of EEG decreased in muscle fatigue. 肌肉疲劳过程中平均脑电值(AEEG)均值增加,平均功率频率值(MPF)和脑电信号复杂度[C(n)]均值下降,该现象广泛分布于整个大脑皮层;
- The attenuation coefficient shows approximately linear behaviour with frequency over the frequency range used,and the attenuation slope increases with the void content. 结果表明:超声衰减系数与频率之间存在线性关系,而且其斜率随孔隙率的增大而增大。
- Review neutral line potential shift protecto,rdepict mostly index of power frequency overvoltage 、 undervoltage and electric surge protection. 通过对中性线电位偏移保护器的回顾,简述了中性线电位保护器的设计思想和工频过、欠电压保护的主要指标。
- The orcs' efforts to escape from the camps or even fight amongst themselves had greatly decreased in frequency over time.The orcs were becoming increasingly aloof and lethargic. 兽人试图越狱逃跑的行为，甚至是他们内部的斗殴都大幅度减少，兽人们变得越来越冷漠和嗜睡。
- The principle of arc-suppression coil with three phases and five columns,and theory of power frequency extinguishing arcing were introduced. 介绍了三相五柱式消弧线圈的工作原理,单相电弧接地过电压的工频熄弧理论。
- For three-phase AC power supply systems and locomotive converter complex and electric locomotives gradually tend to adopt a one-way AC power frequency. 因三相交流供电系统和机车变流装置复杂，电力机车逐渐趋向采用工频单向交流电。
- Secondly, two classical models of distributed parameter DLSP: power frequency model and time-domain model.Based on these two models dynamic phasor model has been deduced. 其次，本文分析了同杆双回线分布参数的两种经典模型：工频量模型和时域模型，并在此基础上推导了时变动态相量模型。
