“…Beyond the assumptions of constant hazard rates, equivalent studies have been concerned with other lifetime distributions. The gamma distribution was addressed in [18], the Weibull distribution was modeled for a series parallel system in [17], the exponentiated exponential distribution was proposed for the parallel system in [19], reliability equivalence factors of a system with a mixture of independent and non-identical components with delay time were obtained in [20], the exponentiated Weibull distribution was considered for a series parallel system in [21], two types of failure rates in a series-parallel systems were analyzed in [22], the reliability equivalence factors of a general parallel system with a mixture of lifetimes were explored in [23], and improving the reliability of a series-parallel system using the modified Weibull distribution was applied in [24].…”