Remanufacturing is recognized as a major circular economy option to recover and upgrade functions from post-use products. However, the inefficiencies associated with operations, mainly due to the uncertainty and variability of material flows and product conditions, undermine the growth of remanufacturing. With the objective of supporting the design and management of more proficient and robust remanufacturing processes, this paper proposes a generic and reconfigurable simulation model of remanufacturing systems. The developed model relies upon a modular framework that enables the user to handle multiple process settings and production control policies, among which token-based policies. Customizable to the characteristics of the process under analysis, this model can support logistics performance evaluation of different production control policies, thus enabling the selection of the optimal policy in specific business contexts. The proposed model is applied to a real remanufacturing environment in order to validate and demonstrate its applicability and benefits in the industrial settings.

Development of technology and expansion of social media emerge group-buying mechanism as a popular strategy. In this paper, two competitive retailers are considered that sell the same product to a customer in a market, group buying and individual buying. Three different competition scenarios are considered. In order to implement the first two strategies, the Stackelberg model is used where the group-buying retailer and the individual-buying retailer are assumed to be the leader and follower, respectively. For the third strategy, the Nash equilibrium is applied when they decide separately. We analyse the optimal and equilibrium strategy in each scenario. And also determine the conditions for each retailer to be present in the market in each scenario. Finally, a numerical example is provided, in order to illustrate the effectiveness of the aforementioned three scenarios in models.