Three repair strategiesJos! e e M. Rocha-Mart! ı ınez* E.S.F.M. del I.P.N., Edificio 9, U. P. ''Adolfo L ! o opez Mateos'', Col. Zacatenco, 07738 M ! e exico, D.F., Mexico
SUMMARYThree imperfect repair strategies, derived from a discrete-time model of failure and repair, are implemented on items brand A (car, computer, washer, etc.), which are low quality with respect to equivalent items brand B (the leading brand in the market) in the sense that items brand A usually fail faster than items brand B do, in order to increase their lifetimes so that they have a chance to compete in durability against items brand B. The implementation of those strategies is performed by probabilistic simulations of the model. The effectiveness of these strategies is measured by comparing the expected 'output' lifetimes of items brand A under each strategy with respect to the expected lifetime of items brand B and the mean value of the total number of repair actions required on items brand A under one strategy with respect to the other two. The algorithm for designing a computer program for simulating those strategies is included. Some results concerning a relationship between a generalized memoryless property of geometric (exponential) distributions and the convolution property of probability (moment) generating functions are detected and also included.