在下游廠商決定上游合作廠商時，廠商出貨產品的品質為重要的決定因素，其中抽樣驗收計畫常常做為確保產品品質的手段，當抽樣品質符合預先設定的品質標準時允收該貨批，否則將拒收。在設定產品品質標準時，產品壽命常常會被視為判斷產品品質的要素，為了估計產品壽命以確定產品品質，過往常常會使用壽命試驗來獲得產品的壽命資料。然而在科技不斷進步的同時，產品壽命也越來越長，因此使用壽命試驗會使廠商花費過多的時間來等待產品的失效發生，或甚至在試驗結束時仍未記錄到產品失效。即使運用加速壽命試驗方法能加速產品失效的發生，但在測試過程中收集到的壽命相關資訊仍然相當有限，於是利用退化資料來評估產品品質的退化試驗便因應而生。退化試驗運用在產品的品質特徵會隨使用時間產生退化的產品上，並且藉由紀錄品質特徵值的衰退來推估產品品質。
　　為了更有效率的獲取退化資料，加速技術也被運用在退化試驗上，雖然使用二種應力水準能夠使設計出來的實驗最有效率，但二應力實驗卻無法驗證設定的模型與實際情況是否相符。在實驗模型設定錯誤的情況下，三應力實驗也會比二應力實驗更具穩健性，於是本研究希望以三應力設計加速實驗提供使用者多一層保障。
　　於是本研究將引用4：2：1理論作為分配不同應力下樣本比例的分配標準，並在考量實驗成本與抽樣風險下，建構一個產品退化服從Wiener過程（維納過程）的三應力水準加速退化試驗抽樣計畫。並以Liao & Tseng (2006)所提供之案例作示範，求得不同參數下之最佳抽樣計劃的設計。

When manufacturers decide on upstream partners, the quality of the supplied products is a crucial determining factor. A sampling acceptance plan is commonly used as a means to ensure product quality. Under this plan, if the sampled quality meets the predefined standards, the batch is accepted; otherwise, it is rejected. Product lifespan is often considered a key element in determining product quality. Traditionally, life tests have been conducted to estimate product lifespan and ensure product quality. However, as technology advances, product lifespans have been increasing, leading to extended waiting times for product failures during life testing or even a lack of failure data by the end of the testing period. To address this, degradation testing using degradation data has emerged as an alternative for evaluating product quality.
This study aims to provide users with an additional layer of robustness by employing a three-level stress design for accelerated degradation testing. The study adopts the 4:2:1 theory as a standard for allocating different sample proportions under various stress levels. Considering the experimental cost and sampling risk, a three-stress levels accelerated degradation test acceptance sampling plan based on Wiener process is developed. Optimal sampling plans under different parameters are designed using a case provided by Liao & Tseng (2006) as a demonstration.

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