چكيده به لاتين
Emergency Medical Services (EMS), plays an important role in health systems. EMS responsible the pre-hospital services such as: providing medical services at the demand points and transporting patients to the proper hospitals.
In this thesis a mathematical model has presented for the medical emergency services services. In addition to locating ambulance bases, the proposed model addresses the location of air ambulance bases and transfer points for dispatching helicopters to on-demand areas, which is important for marginal demand areas and patients with emergencies. In addition, for patients who transported by helicopter to hospitals, hospitals have been designated as helipads. In this case, the patients who have been transferred to the transfer point will be transferred only to the hospitals equipped with helipads.
The objective function of this thesis minimizes the time of transfering from ambulance bases to demand points for the farthest demand point as well as the time of transfer from demand points to hospitals for the farthest demand point. Also, for the purpose of better allocation of emergency facilities to patients and allocation of patients to appropriate hospitals with their physical conditions, disease type classification has been performed for patients. Patients will then be assigned to a hospital that can treat their illness. The uncertainty in this issue is based on the demand and time parameter and uses a scenario-based planning approach to deal with uncertainty. It also addresses the issue of disruption at points of transition that are unable to provide services under specific and unfavorable conditions.
Ahwaz City Emergency is considered as a case study of this thesis. The results of solving the robust model presented using Ahwaz city data show that out of the proposed areas for the construction of ambulance bases, active points are located in the densely populated areas of the city. By comparing the ambulance bases constructed in the certainity situation, it can be stated that the model in robust state to enable all the scenarios and meet the demand of all the regions, activates the ambulance bases in the eastern part of Ahwaz city which has a population density.
By examining the model without considering the transfer points and comparing the results with the mode of considering the points of transfer, it is concluded that the value of the objective function is significantly different in the case of the points of transfer and is better than the case regardless of the points of transfer.
