16 Production Planning of Remanufactured Products with Inventory …
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stage, a growth stage, a maturity stage, and a decline stage. Then, it was shown
that the optimal production plan with the minimal cost was different in each stage
under the time-series forecast of the demand quantity and the collecting quantity
in each period. Hsueh assumed that remanufacturing was performed in continuous
production, and ignored the ordering cost of remanufactured products and the inventory cost of collected used products. Therefore, it would be a more realistic solution
may be obtained by selecting an appropriate type of production system from continuous production and lot production depending on the characteristics of the product.
Furthermore, the effects of product-specific ordering costs and inventory costs on
an optimal production planning, and the effects of uncertainty on the forecasted
demand quantity and collecting quantity depending on product characteristics were
not considered in (Hsueh 2011).
This paper deals with a production plan of products with a short life-cycle and
evaluates the environmental impact by a life-cycle simulation (LCS) technique. The
simulation model includes an inventory management model with system parameters: ordering cost of newly manufactured products and remanufactured products,
and inventory cost of newly manufactured products and collected products. The
demand quantity and collecting quantity are predicted by the product characteristics to each stage divided by the elapsed time since shipment containing introductory/growth/maturity/decline stages. Assuming that the predicted quantity is different
from the actual value, the influence of the system parameter on the optimal production
plan of the newly manufactured products, the influence of the prediction accuracy on
the system cost, and the influence of system parameters on the optimal production
method of the remanufactured products are investigated to each stage.
16.2 Development of LCS Software
16.2.1 Assumptions About the Life Cycle of Recycling
Products
An example of the time-series prediction of demand quantity and collecting quantity
used in this study is shown in Fig. 16.1, in which the characteristic four stages that
exist in the general product life cycle are included.
• Introductory stage: Demand keeps constant at a small value, t ∈ [0, 30]. It is
supposed that there is no collection of the used products at this stage.
• Growth stage: Demand continues to increase significantly after the introductory
stage,t ∈ [30, 60].
• Maturity stage: Demand remains constant at a largest value,t ∈ [60, 135].
• Decline stage: Demand is decreasing due to the appearance of new products,t ∈
[135, 250].
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stage, a growth stage, a maturity stage, and a decline stage. Then, it was shown
that the optimal production plan with the minimal cost was different in each stage
under the time-series forecast of the demand quantity and the collecting quantity
in each period. Hsueh assumed that remanufacturing was performed in continuous
production, and ignored the ordering cost of remanufactured products and the inventory cost of collected used products. Therefore, it would be a more realistic solution
may be obtained by selecting an appropriate type of production system from continuous production and lot production depending on the characteristics of the product.
Furthermore, the effects of product-specific ordering costs and inventory costs on
an optimal production planning, and the effects of uncertainty on the forecasted
demand quantity and collecting quantity depending on product characteristics were
not considered in (Hsueh 2011).
This paper deals with a production plan of products with a short life-cycle and
evaluates the environmental impact by a life-cycle simulation (LCS) technique. The
simulation model includes an inventory management model with system parameters: ordering cost of newly manufactured products and remanufactured products,
and inventory cost of newly manufactured products and collected products. The
demand quantity and collecting quantity are predicted by the product characteristics to each stage divided by the elapsed time since shipment containing introductory/growth/maturity/decline stages. Assuming that the predicted quantity is different
from the actual value, the influence of the system parameter on the optimal production
plan of the newly manufactured products, the influence of the prediction accuracy on
the system cost, and the influence of system parameters on the optimal production
method of the remanufactured products are investigated to each stage.
16.2 Development of LCS Software
16.2.1 Assumptions About the Life Cycle of Recycling
Products
An example of the time-series prediction of demand quantity and collecting quantity
used in this study is shown in Fig. 16.1, in which the characteristic four stages that
exist in the general product life cycle are included.
• Introductory stage: Demand keeps constant at a small value, t ∈ [0, 30]. It is
supposed that there is no collection of the used products at this stage.
• Growth stage: Demand continues to increase significantly after the introductory
stage,t ∈ [30, 60].
• Maturity stage: Demand remains constant at a largest value,t ∈ [60, 135].
• Decline stage: Demand is decreasing due to the appearance of new products,t ∈
[135, 250].