In DVD focus servo system, the skew of the disc induces periodic disturbance whose frequency is the same with the rotation frequency of the disc.

在DVD聚焦伺服系统中，光盘翘曲会导致产生与光盘转动频率相同的周期性扰动。

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At the same time optical rotation of the particles was realized. The rotation frequency was measured by CCD camera and quadrant photodiode detector (QD).

同时利用CCD相机和四像限探测器(QD)测量了粒子光致旋转的转动频率，研究了粒子的旋转频率随激光功率的变化关系。

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Time domain synchronous averaging can reduce the signal not coherent to rotation frequency effectively, and extract the repetitive signals directly related to machine operation condition.

而时域同步平均可以有效衰减与回转频率无关的干扰，提取与工作状态直接相关的周期信号。

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"If the sudden frequency change is neglected, then after only eight hours, a complete rotation of the pulsar is lost in our counting, and we can no longer determine at which rotational phase the gamma-ray photons reach the detector aboard Fermi, " Pletsch explained.

MSN: Oddball pulsating star hiccups as it spins