Assertion: ski tow | /r/CapableOf | utilize system
Facets:
value: to prevent the bull-wheel
type: PURPOSE
value: in the case of a rollback
type: TEMPORAL
Source sentences:
text: In the case of a rollback, some lifts utilize a ratchet like system to prevent the bull-wheel from spinning backwards while newer installations utilize sensors which activate one or more bull-wheel brakes.