On warranty of a multistate system under Phase Type Life

A multi-state system subjected to homogenous Poisson shocks is considered.The systemgetsdeterioratedaccordingtothemagnitudeoftheshocksactedonit.With the known probability distribution of the shock magnitude, the life distribution of the system is modeled under Phase Type distribution assumption.Assuming the life distribution of the system exhibits different life pattern in various places of installation according to the environmental conditions of the place. An optimal warranty period is obtained.