A MULTI-OBJECTIVE ROBUST OPTIMIZATION MODEL FOR LOGISTICS PLANNING IN AN EARTHQUAKE RESPONSE PHASE, CONSIDERING TEMPORARY DISTRIBUTION CENTERS AND MEDICAL CENTERS

Logistics management is a key issue that should be considered for an appropriate response to earthquakes. The problem of interest is the outgrowth of a recent paper [2], where they focused on the logistics of relief items among distribution centers, and the demand nodes and logisticsofinjuredpersonsamongaectedareasandhospitals for a prolonged period of time. The main drawback of their approach is that vehicles require to travel long distances among demand points, distribution centers and hospitals. In fact, they did not consider intermediate/temporary nodes to facilitate the logistics operations. In practice, temporary depots and medical centers are also established to facilitate the logistics of commodities and for serving injured people. This paper presents a multi-objective, multi-period model to manage the logistics of both commodities and injured people in the earthquake response phase. In the presented model, the optimal location of temporary distribution centers and the optimal capacity of medical centers are considered. Relief items can either be directly delivered from distribution centers to aected areas or they can be shipped from distribution centers to temporary depots, and, then, from temporary depots to aected areas. According to uncertain parameters, such as demand quantity, supply quantity, number of injured persons and capacity of medical centers, a robust optimization method is applied to deal with uncertainties. The presented model attempts to minimize the number of unserved persons, the number of unsatised demands and the number of utilized vehicles. The rst two objectives are humanitarian objectives and the third leads to cost eectiveness. The objective functions are of dierent importance. Humanitarian objectives are naturally more important than the third objective. Therefore, the hierarchical approach proposed in [2] is applied to solve the presented model. This approach achieves the optimal solution if the multi-objective model has a single optimal solution. Otherwise, it attains one of the optimal solutions. Finally, the logistics of commodities and injured persons in region 17 of Tehran are studied using the proposed model.