A thermal power source heats up the fluid.
The failure rate of the components depends on the temperature,
the position of the three components monitors the liquid level in
the tank, and in turn, the liquid level determines the temperature.
The main characteristic of this system is that it can be modeled by
a stochastic hybrid process, where the discrete and continuous
parts interact in a closed loop. As a consequence, simulating
this process and computing related reliability index has been a
challenge for the dynamic reliability community. To our best
knowledge, optimization of maintenance policies for the heated
hold-up tank has not been addressed yet in the literature.