由於地球資源有限，且人口持續激增，使得能源緊缺的時期將提前到來，導致環保議題備受重視。因此，愈來愈多的製造商投入舊產品的產品再生活動，其主要理由有二，第一為重覆再利用舊產品，經由再製後的商品因具環保概念而引起消費者的親睞；第二則為政府法令上的限制，讓製造商們能夠在消費者將舊產品丟棄前進行回收且再利用，以符合對環境有利的製造活動。
傳統的生產系統，製造商只有新產品生產線，而加入舊產品回收及再製造後，製造商將同時面對新產品及再製造產品兩種生產系統，稱之為混合生產系統。製造商所需考慮的因素將更加複雜，因此如何擬定適合的生產策略為製造商最關心的議題。故本研究主要針對混合生產系統，將考量製造系統及再製造所涉及的相關成本，例如回收、拆解，建構出製造商的混合生產系統之模式。此外由於產品回收具不確定性及兩種產品存在競爭關係，因此特別將產品間替代關係、產能限制及舊產品的零組件耐用程度皆納入模式，期望使模式更加完備。而模式以追求製造商之利潤極大化為目的，將製造商總收益函數扣除生產所產生的總成本即得利潤函數，透過軟體規劃求得最佳新產品生產數量與最佳舊產品回收率，並將最佳值代回模式，即可得到期望總利潤及期望再製造生產數量。同時本研究利用敏感度分析，找出相關重要參數對本模式的影響關係，進而提供決策者擬定最佳的生產策略。

Owing to the scarceness of natural resources and the increase of the world protection the problem of energy shortage has become a serious issue which has to be deal with nowadays and as a result, the focus of environmental protection has been essentially critical. Therefore, more and more manufacturers and companies are involved in the recycle of used products. This can explained by the following two main reasons: First of all, products with regeneration process are attractive to consumers who possess the concept of environmental protection. Secondly, on account of the restriction of law, manufactures have to effectively recycle and reuse the abandoned old or broken products in order to be beneficial to the environment.
Typical production systems have only new products in production line. When manufacturers collect used-products and perform the process of remanufacturing, they use production lines: for producing the new products and the remanufacturing products, respectively, and which are called “Hybrid system with remanufacturing.” It is desirable to establish a suitable strategy for such a remanufacturing system. In this paper, focus it on a hybrid remanufacturing system, we consider related costs with manufacturing and remanufacturing processes to construct a model in determining the optimal strategy of production. In addition, due to the variability of the collection of used-product and competition between the new and the remanufacturing products, we also consider the impacts of capacity constraint, product substitution and limitations of component availability. The model is utilized by the Lingo software to obtain the optimal new product production quantities and the collect rate of the used-product. The expected total profit and remanufacturing quantities can also be derived. Finally, sensitivity analyses are conducted on various parameters to gain insight into the proposed model.

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