When installed for bilge pumping or ballast duty, centrifugal pumps require a () to remove air from the suction pipe.
An emergency bilge pumping system is provided and should be () of the main bilge pumping system, according to the SOLAS 74 Convention.
A simple pumping system consists of a suction branch, a pump and ().
A simple pumping system consists of a suction branch, a pump and ().
在阿尔卡特的传输设备及光波分复用设备中,大量使用了光放大器,在光放大器中使用了一种功能叫着PUMPING的激光器,该激光器在光放大器中的作用是()。