廢棄物的不當處理可能造成環境的汙染。因此，如何做好廢棄物或報廢物的處理成為重要的研究議題。以往工業界對於不良品的處理多數都採取直接報廢的方式。本論文針對包含供應商和買家的整合供應鏈管理系統，不良品不直接報廢，而考慮將不良品重新送回供應商再生產製造，也就是重工。以系統總成本最小化為目標，來決定最佳的運送次數及生產數量。本研究將所欲探討的問題，建立成一個混合整數的非線性規畫問題，運用非線性規畫問題的求解技巧，找出最佳解的特性。然後根據這些特性，發展出有效的求解演算法，本研究更進一步將此演算法建置成一決策支援系統提供給決策者參考使用。

In this paper, we explore the defective items which can be reworked in an integrated vendor-buyer supply chain for the decision maker to determine the optimal number of shipments per production cycle from the vendor to the buyer and lot size per production cycle. The objective function of the total relevant costs considered in our model is mathematically formulated as a mixed-integer nonlinear programming problem. A complete search procedure is provided to find the optimal solution by utilizing the properties derived in this paper. Also, based on the search procedure developed in this paper, we implement a decision support system (DSS) on a personal computer to solve the proposed problem.

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