隨著科技不斷進步，高科技產品之系統組成越來越複雜，消費者對於產品可靠度要求更是提高。在產品生產過程中，機台一旦出現問題，導致產線必須停機維修，不但影響原定生產計劃，造成消費者損失，也使消費者對廠商不信任，影響後續合作關係，形成雙輸局面。近年來，提供產品保固服務已成為市場上常見的行銷方式之一，一方面，保固可視為廠商對產品品質之信心，有助於吸引消費者購買產品；另一方面，廠商為了降低保固成本，而更著重於提升產品品質，產生正向循環。然而，保固策略隨著產品日漸複雜，提供之服務也越來越多樣化，如何提供有利於廠商以及消費者之保固服務，成為廠商面臨之重大挑戰。
本研究以廠商角度出發，透過建構二維保固成本模型，分析採用預燒試驗與否之成本表現，提供廠商在不同情境下之決策方針。本研究針對較複雜或大型之產品，如汽車、車床或工業用機械等，搭配二維保固販售，並加入預燒以及預防性保養政策進行探討。在早夭期階段，對產品採用加速預燒試驗，目的為篩選早期失效產品，避免失效品流入市場，並透過加速程度縮短預燒時間；而使用期以及磨耗期階段，則透過周期性預防保養，並引用虛擬年齡概念在固定期間對產品進行不完美維修，目的為避免產品在使用過程中失效，以降低使用者損失，同時減少廠商保固成本，透過演算法求得最佳預燒時間以及最佳預防保養間隔，使廠商保固成本最小化。我們發現當保固維修成本高以及產品早期失效率高時，廠商採用預防保養之決策較佳，且透過敏感度分析我們也發現，保固維修成本對廠商總保固成本造成之影響最大。

This study investigates a two-dimensional warranty for a complex and large scale product, such as a vehicle, lathe, or industrial machinery, with consideration of
burn-in and preventive maintenance. Two-dimensional warranties consider both usage and age, which are different from one-dimensional ones that only consider
age, for different types of consumers. For example, vehicles are often sold with basic warranties of three years or 10 thousand kilometers, and the warranty would
be terminated when either the age or usage reaches the predetermined requirement.
Burn-in is the testing process to identify defective products under supervised
conditions and prevent the introduction of products, which may have failures occurred, in the premature period to the market. Periodic preventive maintenance
can reduce the occurrence of unexpected failures under normal usage, prevent consumers’ loss, and decrease the warranty cost. Previous studies on one-dimensional
or two-dimensional warranties often investigated preventive maintenance policies and the integration of warranties and burn-in. Research on the integration of burn-in and preventive maintenance into two-dimensional
warranties has not been extensively studied. Thus, this study investigates the optimal two-dimensional warranty with consideration of the burn-in and preventive maintenance to reduce the product failure rate with the aim of minimizing the costs for the firm.

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