Aiming at the shortage of conventional overhead travelling crane control system, the application of a novel control and protective switch in innovation for overhead travelling crane was introduced.

针对传统天车控制系统的不足，介绍了一种新型控制与保护开关在天车改造中的应用。

youdao

Perhaps the more significant, and less noted, event that forced Romney to switch his protective coloring was the resignation in September 2004 of House Speaker Tom Finneran, a staunch social conservative who ruled the Massachusetts House with an iron hand.

CNN: Will Romney lurch to the center?

Sir Alex Ferguson made a tactical switch after 66 minutes, replacing Saha with John O'Shea, who was pushed into a protective role in front of the back four.

BBC: Wayne Rooney celebrates putting Man Utd ahead in the derby