This paper develops an economic production quantity model in a three-echelon supply chain composing of a supplier, a manufacturer and a wholesaler under two scenarios. As the first scenario, we consider a return contract between the outside supplier and the supplier and also between the manufacturer and the wholesaler, but in the second one, the return policy between the manufacturer and the wh...

This paper consideres an optimal ordering and replacement problem of a continuous time Markovian degradation system. An optimal policy minimizes the expected cost per unit time in an infinite time horizon. The problem is formulated by semi-Markov decision process and the optimality of an (n,N)-policy is shown. Further, the expected cost rate of the system operated under an (n,N)-policy is obtai...

This study analyzes an inventory control problem of a company in stochastic demand environment under carbon emissions regulations. In particular, a continuous review inventory model with multiple suppliers is investigated under carbon taxing and carbon trading regulations. We analyze and compare the optimal (Q,R) policies with order splitting under two ordering policies: sequential ordering and...

BACKGROUND Erythropoiesis-stimulating agents (ESAs) are recommended for treating anemia in patients with chronic kidney disease and end-stage renal disease. However, misappropriate and over-use of these agents can be costly and unnecessary in some settings. OBJECTIVE The primary aim was to identify predictors of adherence to a newly approved ESA inpatient ordering policy. The secondary aims w...

This paper presents a computational intelligence approach for coping with bullwhip effect in supply chains (SCs). An imperialist competitive algorithm (ICA) is employed to decrease the bullwhip effect and cost (inventory, ordering and production) in the MIT beer distribution game. The ICA is used to determine the optimal ordering policy for members of the SC. The results shows the ability of th...