The control principle of step motor is exposed, drive control of feed system is carried out by use of motion controller, meanwhile, dot motion control of step motor is also carried out by use of PLC.

阐述了步进电机控制原理，利用运动控制器实现了进给系统的联动控制，利用PLC实现了步进电机的点动控制。

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SilverStone makes many different HTPC style cases, but we chose this one because of its two large cooling fans, six internal hard drive bays, plain black front (no VFDs or exposed ports), solid construction, and it is rackmountable.

ENGADGET: How-To: Build a practical HTPC

Like Dr Hawkins, he believes it won't drive down HIV rates, but could be very important to individuals who have been exposed to the disease.

BBC: NEWS | UK | Magazine | 'Morning-after' pills for HIV?