A bi-objective sustainable EOQ model with all-units discounts
研究了一个考虑全单位折扣的双目标可持续EOQ模型，同时最小化成本和二氧化碳排放，并刻画了帕累托最优解集的特征，对库存管理者和可持续运营研究者有参考价值。
A bi-objective sustainable Economic Order Quantity (EOQ) model considering all-units discounts is addressed. Two criteria are considered in the model, namely, the classical cost function of the EOQ and a CO 2 emission function, which must be simultaneously minimized. Moreover, all-units discounts are taken into account since they are a very common practice in real world wholesalers/sellers businesses to encourage higher volume sales in order to reduce the inventory level. Therefore, the aim of the new model is to identify the non-dominated solution set (Pareto optimal set). It will be shown that the Pareto optimal solution set for the new sustainable EOQ variant is not always a convex set (or equivalently, the nondominated solution set could occasionally be non-continuous) and this set is defined by means of cases study (depending on the problem’s variables values). The new characterization of the Pareto optimal set of the new extension of this bi-objective sustainable EOQ model allows us to define the corresponding Pareto frontier. These findings have been implemented in Python and tested for a randomly generated set of instances.