Description: period of time during which a system or component is operational and in service, but not in use; Name: it
Description: Time interval throughout which an item is in an idle state; Name: Idle time
Description: translation i of a pair of gears or a multiple gear pair is the ratio of the angle speed wa (or the speed na) of the first driving wheel to that of the last driven wheel wb (or nb); Name: Transmission ratio of the transmission