针对自适应前馈控制方法的缺点，提出一种周期性振动主动控制的自适应反馈控制方法。
As the adaptive feedforward control method used for active control of periodic vibration has many shortcomings, an adaptive feedback control method was proposed based on on-line frequency estimation.
本文通过尾水管内流动的模拟，导出了由尾水涡带所引起的周期性振动的振动频率和脉动压力的计算公式。
This paper gives the flow simulation of hydraulic turbine draft tubes. Then, the calculation formula of the frequency and force of vibration of the draft tube are derived.
海浪是海面起伏形状的传播，是水质点离开平衡位置，作周期性振动，并向一定方向传播而形成的一种波动。
The waves of the sea is the shape of the spread, and is left at the water quality, balance position periodic vibration and spread to certain direction, in the form of a wave.
应用推荐