Ana dağıtım üssü kaplama akış problemi ve kapasite kullanımı

Hub location problems occupy an important place among transportation problems. In such problems, each node in the network including hubs can be the origin or destination point of a transport demand. What makes hubs different from the other nodes is that they also act as transit points, that is, they enable the combined demand moved from different origin nodes to be sent by separating according to destination nodes. The existence of hubs simplifies the structure of the transport network. At the same time, hubs ensure better use of the capacity of transportation vehicles and decreases the unit transportation cost due to the possibility of transporting large volumes between hubs. Hub location problems are frequently encountered in the design of cargo distribution, airline passenger transport and telecommunication networks. In this study, hub-covering problem, which is a special hub location problem, is emphasized. The basic assumption for this type of problems is that some nodes in the network cannot be directly or indirectly connected due to distance, time or cost constraints. Capacity utilization and transportation costs are generally ignored in the mathematical models developed for the hub - covering problem. To fill this gap in the literature, a deterministic multiple assignment mixed integer optimization model has been developed. How and to what extent the change in different model parameters affects the best solution for the proposed model was examined by numerical experiments using a benchmark data set. As a result, it was revealed how important it is to consider the aforementioned elements in the hub -covering problem and practical insights have been provided.