Location of facilities in the design of the global logistics hub network taking into account the time discount coefficient

In this research, the problem of designing a logistics hub network to improve flow management in the implementation of global transport operations has been investigated. In this case, shipments can be moved directly or indirectly between points. In indirect shipping mode, the shipment first enters the hub network and then is sent to customers. In this case, there is a certain discount factor that reduces the time it takes for the product to reach end customers. The objective function of the proposed model is to minimize the fixed costs of constructing a hub, the cost of constructing an inter-hub infrastructure, the cost of transportation if the equipment is transported directly, and the cost of transportation if the hub network is used. The limitations of the model also include locating logistics hubs, managing flow between points, calculating transport time, and finally managing flow between network points. To evaluate the performance of the proposed model, a researcher-made numerical example based on real-world conditions with randomly generated data and sensitivity analysis on the problem outputs was performed. According to the results, it can be seen that the proposed model can produce justified and optimal global answers and therefore can solve real-world problems. Also, based on the sensitivity analysis, it can be seen that with increasing the amount of capacity, the values of the target function decrease. In other words, if capacity is increased, there is a need for fewer vehicles and thus costs are reduced. It is also clear that as capacity increases, the number of vehicles to respond to decreases. In fact, the greater the carrying capacity, the easier it is to manage the flow between the hubs as well as the direct transmission, thus reducing the number of vehicles. In addition, as the cost of building infrastructure increases/decreases, the cost of the entire system is affected.