Coordinating In Supply and Distribution of Relief Items in Humanitarian Logistics Based on Quantity Flexibility Contracts and Outsourcing

In this study, we examine a supply chain of several products and four levels including suppliers (domestic and foreign), relief organizations (Red Crescent Organization), demand points (patient wards in the hospital). The Quantity Flexibility Contract provides coordination for inventory management by determining the order quantity between the relief organization and the internal supplier. Due to the many shortcomings, limited construction time and lack of facilities for mass production and increased costs, the use of outsourcing can increase the expected sales of the chain and also provide faster relief in times of crisis. Therefore, by presenting a mathematical model to minimize costs and times, we try to provide relief to the injured at the lowest cost and in the fastest time. By solving the model, we found that among the various parameters, the objective function is more sensitive to the demand parameter and domestic production capacity than other parameters, which shows the necessary accuracy of planners in this field to these parameters in crisis situations.