Study On Two-dimensional Product Warranty Policy Design And Optimization

Since the adoption of reform and opening-up policy in China,the level of product's quality management has made a huge improvement.However,there are still lots of problems need to be solved in product warranty policy design and optimization especially for complex products,such as automobiles and large equipments.Meanwhile,the theory of complex products' warranty policy design and optimization is insufficient to help the manufacturer to make related decisions.Based on our survey on the related manufacturers and literature review on warranty,complex products' two-dimensional warranty policy design and optimization plays a significant role in after-sales service.Accordingly,this dissertation focuses on complex products' two-dimensional warranty policy design and optimization to help the manufacturer to make related decisions.Firstly,the optimal two-dimensional warranty policy is designed and optimized based on a new demand function.The manufacturer often has to make a trade-off between raising warranty cost and boosted demand when designing a longer warranty period.Considering the attractiveness of two-dimensional warranty policy for different usage rates of customers,a new demand function is proposed to model the effect of warranty period on boosting product's sales.Based on the proposed demand function,the boosted sales quantity is analysed when extending the two-dimensional warranty period.Meanwhile,expected warranty cost of two-dimensional warranty is calculated to estimate the raised warranty cost.The optimal two-dimensional warranty policy is designed to maximize the manufacturer's expected profit.Both numerical experiments and a case of truck market in China are conducted to test the performance of the proposed method.Secondly,a customized two-dimensional warranty menu is proposed and optimized for customers with heterogeneous usage rates.Customers are heterogeneous in many aspects such as usage rates,customer's habit and risk attitudes.Heterogeneous customers have different needs on the warranty policy.For a two-dimensional warranty policy,heterogeneous usage rate of customers have different perceptions on warranty period.An attractiveness index is proposed to model customers' perceptions on warranty period with different usage rates.The principles and procedures of designing a customized two-dimensional warranty menu are proposed.Meanwhile,the optimal division strategy of customers and when customers are uncertain of their usage rate are discussed.Numerical experiments of automobiles' warranty menu design are conducted to test the performance of the proposed method.Lastly,the optimal two-dimensional warranty policy,sales price and reliability are jointly designed and optimized from the perspective of product life cycle.Related costs in design process,manufacturing and production,marketing and after-sales service are analysed.The expected profit of the manufacturer during the sales period is calculated.The optimal two-dimensional warranty policy,sales price and reliability in both static market and dynamic market are proposed.Numerical experiments of automobiles based on the proposed method are conducted.Based on the proposed method,this dissertation enriched the related theories on warranty policy design and optimization,and helped the complex products' manufacturers to solve the related two-dimensional warranty policy design problems.