In system designing, this dissertation introduces the mechanism of system design, and designed the system hardware parts, including the mech-electronic control parts and the related circuits.

在此基础上，重点研究了液晶电视特性参数综合测量系统的硬件设计，包括整个机械部分的设计及部件选择，机电控制部分的控制方案及电路设计。

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Derailleur gears have a front mech (short for front gear mechanism) to shift the chain between two or three chainrings and a rear mech (short for rear gear mechanism) with up to 10 sprockets.

BBC: Sport