本研究探討回收具有來源不確定性之共用元件，再製造後銷售產品到市場之問題。系統生產兩種共用同一回收核心元件之再製造產品，分別滿足高級 (high end) 與普通 (low end) 兩種市場需求。每一期，企業必須根據存貨水準決定共用核心元件回收量、兩種產品的再製造量、以及兩種產品的供給量。每期可回收的核心共用元件數量是隨機變數。決策變數間的相依性與回收數量的不確定性使得本問題變得非常複雜。若無妥善的管理機制將導致企業利潤顯著降低。本研究利用連續決策過程 (Sequential Decision Process) 建構數學模式，並運用數值迭代法 (Value Iteration Algorithm) 有效率求解，目標是最大化產品規劃周期內總利潤。求得之穩態解有助於探討決策變數與存貨水準間的關係，最後我們還探討可回收數量變異對於決策變數的影響。

This paper presents a dynamic stochastic optimization model to jointly determine marketing and operations decisions in a remanufacturing system. In the system, two remanufactured products share a common recycled core component. One remanufactured product is for the high end market and the other is for the low end market. The company has to decide how many common core components to recycle, how many high end and low end products to remanufacture, and how many high end and low end products to sell in each period given the market conditions. The main source of the uncertainty is the number of the common recycled core component available in each period. The inter-dependence among decision variables and the uncertainty make this problem extremely complicated. Without proper control policies, the company will result in significantly lower profits.
Sequential decision processes are used to formulate the problem. The objective is to maximize the sum of total profits over the planning horizon. Efficient value iteration algorithm is developed to solve the problem. The stationary solutions provide relationships between values of decision variables and inventory levels. The impact of the uncertainty is also discussed.

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