| Almost all products are released to the market with warranty. From a manufacturer's point of view, designing a good maintenance program is an important issue. This dissertation develops maintenance policies under warranty period to minimize the total warranty cost. This research consists of two major parts: Maintenance policies under one-dimensional warranty period and maintenance policies under two-dimensional warranty period.; For one-dimensional warranty problems, maintenance policies which consist of minimal repair and preventive maintenance are analyzed for cases of known and unknown failure parameters of the item's failure distribution.; For the second case, two types of Bayesian policies are considered. An extensive simulation comparing the performance of these maintenance policies is performed.; For the two-dimensional warranty problem, three maintenance/replacement policies are proposed. Under the assumption of a linear relationship between usage and time after purchase, a replacement policy with control limits and a maintenance policy consisting of minimal repair/preventive maintenance are studied. A maintenance policy modeled by dynamic programming is also studied. |
