Noksan onarım altında garanti maliyeti analizi

AbstractWARRANTY COST ANALYSIS UNDER IMPERFECT REPAIRGülay SamatlıM.S. in Industrial EngineeringSupervisor: Asst. Prof. Mehmet Rüştü TanerNovember 2006Increasing market competition forces manufacturers to offer extensive warranties. Faced withthe challenge of keeping the associated costs under control, most companies seek efficientrectification strategies. In this study, we focus on the repair strategies with the intent ofminimizing the manufacturer?s expected warranty cost expressed as a function of variousparameters such as product reliability, structure of the cost function and the type of thewarranty contract. We consider both one- and two-dimensional warranties, and use quasirenewal processes to model the product failures along with the associated repair actions. Wepropose static, improved and dynamic repair policies, and develop representative costfunctions to evaluate the effectiveness of these alternative policies. We consider products withdifferent reliability structures under the most commonly observed types of warranty contracts.Experimental results indicate that the dynamic policy generally outperforms both static andimproved policies on highly reliable products, whereas the improved policy is the bestperformer for products with low reliability. Although, the increasing number of factors arisingin the analysis of two-dimensional policies renders generalizations difficult, several insightscan be offered for the selection of the rectification action based on empirical evidence.Keywords: Imperfect repair, quasi renewal processes, two-dimensional warranty, warrantycost, numerical methods