Phased Mission Systems—Modeling and Reliability
All complex systems can be considered as a collection of subsystems where each subsystem does its designated job. An automobile consists of several 142mechanical, electrical, and automated subsystems. Such systems are called phased mission (PM) systems. The system works when the subsystems work sequentially in several phases to complete the job for which it was designed. Another example of a PM system is an aircraft flight—different phases of the flight consist of takeoff, the ascent of the aircraft, altered flight due to interfaces, descent, and finally the landing. A boiling water reactor could face a “loss of coolant” accident. The corrective action in this case consists of three phases—cooling of initial core process, suppression core cooling, and removal of residual heat. Computer processing units, communication satellites, and satellite launchers are other examples of PM systems.