Prescheduled switching time: A new strategy for systems with standby components

Abstract

Reliability improvement is a major industrial concern. A commonly known approach to improve the reliability of a system is the so-called ‘redundancy strategy’ in which redundant components are used in the subsystems to achieve considerable enhancements in total system reliability. Generally, the two active and standby strategies are the ones most used in addressing reliability optimization problems (ROPs). The present article proposes a new structure for the standby strategy that revolutionizes its conventional structure into one that considers a predefined time at which a component starts operation without the need for a switching system to activate it. The standby component actively enters the system at the predefined time; this naturally improves system reliability by relaxing the need for the switch to a considerable extent, which is especially useful in cases of a poor switching system. The objective in this problem is to determine the best time for the component to join the system. According to the new strategy, the system typically uses its switching system whenever there is a need for a component to join the subsystem but the component may also join the system automatically at a predefined time in order to reduce the likelihood of system failure.