Some new applications of the total time on test transforms

The concept of total time on test transforms (TTT) is well known for its applications in different fields of scientific study. In this article we present four applications of TTT in reliability theory. First we characterize ageing criteria such as IFRA and NBU in terms of TTT. Then we utilize an iterated version to construct bathtub shaped hazard quantile functions and corresponding lifetime models. Further, an index is developed for numerically measuring the extent of IFR-ness of a life distribution. Finally we demonstrate how the distributional properties such as kurtosis and skewness can be derived from the TTT.