The noise generator is used as a basic USB device, USES the control transfer and interrupt transfer.
本课题设计的噪声发生器作为基础usb设备，采用了控制传输和中断传输。
By use of VVVF technology to directly control elevator door operation simplified the mechanical structure of elevator door device with low noise in door closing and leveling in exact position.
采用VVVF技术对电梯开门机直接拖动，使电梯门机装置机械结构简化，关闭时噪声低，且可靠到位。
Muffler is the conventional muffling device in the noise control of compressor.
消声器是压缩机噪声控制中常用的消声装置。
Muffler is the conventional muffling device in the noise control of compressor.
消声器是压缩机噪声控制中常用的消声装置。
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