本研究的目的是要針對可維修產品,探討MLP-2(multi-level sampling plan with two sampling inspection levels)與精密檢驗之最適混合檢驗策略。更明確地說,在考量檢驗誤差與退貨成本下,以最大化平均單位利潤為目標,探討MLP-2之最佳清查個數(clearance number)和各層的抽樣頻率(sampling frequency),以及於MLP-2抽樣檢驗程序中未檢驗、判定為良品與不良品之產品,施予最佳精密檢驗之比率。分析結果顯示,MLP-2有兩種主要的檢驗策略:(1)一直執行百分百檢驗和(2)自百分百檢驗進入抽樣檢驗後即停止檢驗。而於MLP-2檢驗程序中未檢驗、判定為良品與不良品之產品,應施予精密檢驗之兩種主要比例為:0%和100%。
Under the conditions that inspections in MLP-2 are not perfect and each defective shipped to the buyer will be fined a return cost, this paper investigates a mixed policy between precise inspection and MLP-2 for repairable products. By using the criterion of maximizing the unit net profit, the following decision variables are determined: (1) the optimal clearance number, (2) the optimal sampling frequency of each level, and (3) the proportions on which precise inspection should be taken for the defectives and the non-defectives identified in the procedure of MLP-2 and the non-inspected items. Analytical results indicate that there are two main inspection policies for MLP-2: ”Continue 100% inspection” and ”Stop inspection after 100% inspection;” besides, for the defectives and the non-defectives identified in MLP-2 and the non-inspected items, two main proportions which should be performed precise inspection are: 100% and 0%.