探討多次定期等量運送對不良品部分可重工修復之生產系統的批量與運送次數之最佳決策

Determining the optimal production - shipment policy for EPQ model with multiple deliveries and repair of reworkable defective items

張瀞云(Ching-Yun Chang)

指導教授 ： 邱元錫

朝陽科技大學/理工學院/工業工程與管理系/碩士(2009年)

摘要

本研究使用數學模式推導出最佳生產批量及最佳運送次數，在不完美生產系統中包含不良品部分可重工修復，以及良品分期定量運送，並統整顧客端的良品持有成本，使期望年存貨成本最小化。假設生產過程不完美，且不良品在進行重工前會先挑出無法重工的部分先予以報廢，而剩下的不良品在重新加工修復後均可以完全修復。由於傳統經濟生產批量(EPQ)所假設的需求為連續運送與現實情況有所差異，故本研究為符合實際狀況，探討分期定量運送模式。

本研究針對以上假設建立三個數學模式：(1) 產品在重工完成後進行運送且包含顧客端存貨持有成本之最佳生產批量及運送次數之決策；(2) 在重工完成前運送且重工時間小於運送間隔時間並包含顧客端存貨成本之最佳生產批量及運送次數之決策；(3) 在重工完成前運送且重工時間大於等於運送間隔時間並包含顧客端存貨成本之最佳生產批量之決策。接著提出實例來做驗證，並對其參數做敏感度分析，期望本研究之模式能夠因應實際情況，提供業界處理不良品重工與分期運送上可以作為參考之依據。

關鍵字

分期定量運送 ； 不完美品質生產系統 ； 不良品部份可重工修復 ； 報廢品 ； EPQ ； 最佳運送次數

並列摘要

This paper determines the optimal lot size and delivery policy for Economic Production Quantity (EPQ) model with reworkable defective items. Traditional EPQ model assumes a continuous delivery policy, but it is not practical. Therefore, this paper studies a multiple delivery policy to conform to the real-life situation. In additions, it is assumed that production process system is imperfect, random defective items are produced due to various inevitable reasons. Not all of defective items are reworkable, a portion of defective items are scrap and are to be discarded before the rework process. The purpose of this study is to determine the optimal lot size and delivery policy for such a realistic system in order to minimize its overall costs.
Three different models are investigated in this study, they are: (1) model of delivery shipments after rework with double variable (Q*,n*). (2) model of delivery shipments before rework and rework time greater than each delivery time with double variable (Q*,n*), and (3) model of delivery shipments before rework and rework time less than each delivery time with single variable (Q*). In the last, numerical examples are provided to demonstrate its practical usage.

並列關鍵字

Multiple deliveries policy ； Imperfect production system ； Repair of reworkable ； Scrap item ； EPQ

參考文獻

[58]王聖嘉，「探討經濟生產批量模式含不良品重工之最佳決策」，博士論文，中原大學工業工程研究所，台中(2003)。

[1]Aderohunmu, R., Mobolurin, A., and Bryson, N. Joint vendor-buyer policy in JIT manufacturing. (1995) Journal of the Operational Research Society, 46 (3), 375-385.

[2]Agnihothri, S. R. and Kenett, R. S., “Integrated production inventory models for imperfect production processes under inspection schedules”, Computers and Industrial Engineering, Vol. 44, Issue 4, pp. 633-650 (2003)

[4]Ahmad Diponegoro, Bhaba R. Sarker, “Finite horizon planning for a production system with permitted shortage and fixed interval deliveries”, Computers & Operations Research, 33, 2387–2404 (2006).

[5]Beatriz Abdul-Jalbar, Jose’ M. Gutie’ rrez, Joaquı’n Sicilia, “An integrated inventory model for the single-vendor two-buyer problem”, Int. J. Production Economics, 108, 246–258 (2007).