PLA (People’s liberation army) is the world’s largest military force. It consist of five department which includes the ground force, naval force, air force, rocket force and strategic planning force.
Chinese cops while learning their posture take help of stick, pins, cross stick for back.
These cops insert pins to their collar to ensure having the perfect posture. A slight change in position and the pain would remind them to keep their attention and hence avoid sleepiness.
Image 1 and 2 source: mirror.co.uk )
The picture well depicts how discipline is followed while serving in offer.