Description: Determined integral of the sound power p over a specified time interval of duration t (starting at t1 and ending at t2); Name: Energy of sound
Description: determined integral of the sound power, p, over a stated time interval of duration t (starting at t1 and ending at t2); Name: sound energy
Description: During a given period of time, percentage of the time during which an item was able to perform when required ; Name: Time based availability