Yardım kuruluşlarının yardımlaşması altında afet öncesi yardım malzemelerinin envanter planlaması

Frequent disasters with devastating consequences have been experienced worldwide within the last decades. In the preparedness phase of disaster management, relief inventory pre-positioning plays a vital role to achieve successful delivery of relief aid. In this study, we analyze two cooperation scenarios between two relief agencies which aim to optimize their pre-disaster stocking decisions by means of a newsvendor-based quantitative model. In the first scenario, both of the organizations agree to share their residual inventory and also decide on their stocking levels together to optimize their joint efforts. In the second cooperation scenario, they agree to share their residual inventory, but they give their stocking decisions independently and try to optimize the "returns" from their own aid efforts. We obtain the unique optimal inventory levels under a Centralized Model (CM) and the unique Nash Equilibrium under a Decentralized Model (DM) analytically. We also conduct extensive numerical analyses to get insights about the importance of cooperative efforts by introducing the term "price of anarchy" into the humanitarian operations literature stream. Moreover, relief items may not reach the other organization intact or the arrival time of the aid may be late. Therefore, the organization that faces stock-out after demand realization cannot use all the items which come from the other organization. As another novel contribution, we introduce the ratio of usable relief items as a "reliability factor" and the existence of this factor changes the analytical findings completely. We believe that our study leads to useful insights for humanitarian organizations which may ignore the importance of horizontal cooperation and doubt the resulting opportunities.