Improvement of Instantaneous Availabilities by Decreasing Delay Time

Many situations exist where a system cannot go to a repair station immediately when a unit fails. This paper models a 1-out-of-2:G hot standby system which is used intermittently. The system in Model I is a 2-unit parallel redundant system where only one user is allowed in the system. However, in Model II, two users are allowed to use the system. Model II uses two units independently (it is not a 2-unit parallel redundant system) when two users are in the system. Model I is equivalent to Model I when there is only one user in the system. Two problems are discussed: 1) the effect of a delay time on instantaneous system availability, 2) the possibility of trade-off between the delay time and the failure rate of a unit on instantaneous availability.