OPTIMUM GENERALIZED COMPOUND LINEAR PLAN FOR MULTIPLE-STEP STEP-STRESS ACCELERATED LIFE TESTS

In this paper, we consider an  i.e., multiple step-stress accelerated life testing (ALT) experiment with unequal duration of time . It is assumed that the time to failure of a product follows Rayleigh distribution with a log-linear relationship between stress and lifetime and also we assume a generalized Khamis-Higgins model for the effect of changing stress levels. Taking into account that the problem of choosing the optimal time for ۳-step step-stress tests under compound linear plan was initially attempted by Khamis and Higgins [۱۶]. We ever first have developed a generalized compound linear plan for multiple-step step-stress setting using variance-optimality criteria. Some numerical examples are discussed to illustrate the proposed procedures.

Keywords:

accelerated life testing , Rayleigh distribution , cumulative exposure model , maximum likelihood estimate , generalized compound linear plan