不完美生產系統下，考量不良品重工及原物料補貨之經濟批量排程問題

On an Economic Lot Scheduling Problem under an Imperfect Production Process with Reworks and Raw Materia

林智勇(Jhin-Yong Lin)

指導教授 ： 宮大川

中原大學/電機資訊學院/工業與系統工程研究所/碩士(2011年)

https://doi.org/10.6840/cycu201101099

摘要

本研究以上下游製程中，不完美生產系統下的「經濟批量排程問題」為基本架構，同時考量原物料補貨、製程內檢驗、不完美重工製程、丟棄以及短缺。由於生產設備的老化可能使生產製程退化，導致製程偏移至失控狀態，並產生出不良品，因此本研究假設每一個產品被生產出來後，會立刻由檢驗製程檢查並將良品或不良品分類。所有產品被檢驗後，所有不良品會經由重工製程進行重工。然而，重工製程並非完美，無法將所有不良品重工成為良品，還是有部分產品必須被丟棄，且因此造成下游製程的需求短缺。根據上述不完美生產系統下的經濟批量排程問題，利用共同週期法建立數學模式。其目標是決定一組近似最佳解以最小化每單位時間總成本。近似最佳解包涵共同週期以及每種原物料補貨的間隔週期（每次補貨量可供給多少週期的用量）。本研究根據三種方法提出三種演算法進行求解，包括二分法、封閉形式解以及粒子群演算法，並利用數值範例驗證所提出的模式。最後進行敏感度分析並探討分析的結果。本研究試圖為同時考量不良品重工以及原物料補貨之不完美製程中的經濟批量排程問題，提供管理者指引以評估適當的生產週期以及原物料的採購量。

關鍵字

檢驗 ； 重工 ； 不完美製程 ； 原物料補貨 ； 經濟批量排程問題

並列摘要

This research focuses on solving the Economic Lot Scheduling Problem (ELSP) under an imperfect production process that includes joint material replenishment, in-production screening process, imperfect rework process, scraps and shortage. The aging of a production facility may deteriorate the production process and the facility may shift to an out-of-control state wherein nonconforming items are produced. All defective items, which are defected by the screening process, may be reworked immediately after the production process finishes. However, since the rework process is imperfect, scraps are produced during the rework processes. The ELSP, in a deteriorating production system, is formulated by the Common Cycle (CC) approach. The objective is to determine near-optimal solutions, which include a common production cycle time and replenishment cycles of raw materials, for minimizing the expected total cost per unit time. Three problem solving procedures are developed to find near-optimal solutions for the proposed model. To demonstrate the model, the study provides a numerical example that illustrates the derivation of the solutions. Sensitivity analysis is also performed and discussed. The results show that the proposed deterministic model can provide managers with guidelines for evaluating the proper production cycle time and the purchase quantity of raw materials under a joint material replenishment policy.

並列關鍵字

rework ； imperfect production process ； screening process ； economic lot scheduling problem ； raw material replenishment

參考文獻

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