Li and Zhang (2010) considered the problem of construct
asymptotic confidence interval for the ratio of means of two two-parameter exponential distributions. Kharrati-Kopaei
et al. (2013) consider simultaneous fiducial generalized confidence intervals for differences of the location parameters of
several exponential distributions under heteroscedasticity. In the quality control study and the experimental design, a more
important parameter of interest is the mean lifespan of certain products. For example, it is known that the product quality
directly affects the competitive advantage of an enterprise in the market. The quality of the product and its lifespan are