Development of Three-Objective Model for the Location - Allocation of Assistance Centers in a probabilistic Condition of availability to emergency Vehicles

In this paper, the considered set covering issue is a stance of location-allocation issue in which the residents of each the eighteen district of region 6 of Tehran, have definite requirements to receive services (medical first aid) from some of emergency centers. We want to arrange so that at least one center, in each district, provides services to people who have been exposed to incidents. In this regard and to emplacement of these relay centers, a developed multi-objective model is used that has objectives such as minimizing the establishment cost of relay stations, maximizing the total covered population and minimizing the total distances between demand locations and allocated service providers. Since, each of the centers has only an ambulance and these ambulances being out of reach during providing services, possible limitations have been used in this model. So, in this research a combination of multi-objective decision making (MODM) methods and set covering problem (SCP) is used to specify the location of relay centers in 18 districts of region 6 in Tehran. The chosen solution is simulated annealing method that is performed using Matlab software. At the end, the model is implemented through the Ultra Innovative algorithm of particle mass optimization to compare to the answers of the Simulated Annealing algorithm. Results show that both algorithms give the same answers for the considered locations.