The two major components are: a mechanical drive system and an optical system.

两个主要部件为：一是机械传动系统，另一个部件为光学系统。

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So the theoretical basis is given for design, parameters choice and performances improvement of mechanical drive system.

为机械传动系统的设计、参数的选择以及性能的改进提供了理论依据。

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Familiar with hydraulic systems, pneumatic components, solenoid valves, and mechanical drive system, understand PLC control theory.

熟悉液压系统，气动元件，电磁阀，及机械传动系统，了解PLC控制原理。

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Helping Komatsu persuade the mine operator to switch was a new drive system that instead of the conventional mechanical axle and cogs uses rear-wheel-mounted electrical motors.

FORBES: Magazine Article

Under its shiny new skin, new hardware and software, such as a slimmed down version of Apple's OS X operating system and a flash memory drive, instead of the current iPod's mechanical hard drive, could keep the new device thin and light.

FORBES: The Next iPod