The piston slides noiselessly up and down. 这个活塞上下活动,没有响声。
The traditional transformer is trending towards pocketsize and noiselessly in inverter using high-frequency link technique,but the control circuit becomes difficult to be designed. 高频链技术使逆变器中变压器趋向于小型、无噪声化,但增加了控制电路的设计难度。