Hub-and-spoke emergency rescue network planning

In order to achieve the rapid rescue of disaster-stricken cities and simultaneously reduce the construction cost of emergency rescue networks as much as possible, the multi-objective planning method of the three-level hub-and-spoke emergency rescue network was studied by taking the locations of emergency rescue stations and the layout of emergency rescue channels as the foothold. The multi-level structure of the hub-and-spoke network and the characteristics of connection relationship between emergency rescue stations were considered, the locations of three-level emergency rescue stations, the connection relationship between emergency rescue stations, and the level of emergency rescue channels were taken as decision variables, the minimum construction cost of emergency rescue stations at all levels and the minimum average network rescue time were taken as the two objective functions, a three-level hub-and-spoke emergency rescue network planning model was bulit. The niche Pareto genetic algorithm with a three-segment encoding structure for the three-level hub-and-spoke emergency rescue network planning model was designed by combining the characteristics of the decision variables. The emergency rescue network was modelled and solved based on the road network of 14 cities in Gansu Province. The effectiveness of the method was verified, and the optimization results were compared with the traditional three-level emergency rescue network. Research results show that the niche Pareto genetic algorithm with a three-segment encoding structure can effectively solve the hub-and-spoke emergency rescue network planning model. Compared with the optimal solution of the traditional emergency rescue network model, the selected scheme of the Pareto solution in the three-level hub-and-spoke emergency rescue network can reduce the construction cost of emergency rescue stations by 8. 3%, and accelerate the average network rescue time by 3. 5 h. The optimization results can dominate the optimal solution of the traditional emergency rescue network. So, the proposed three-level hub-and-spoke emergency rescue network planning method can take into account the intensive characteristics of hub-and-spoke networks and achieve shorter emergency rescue time.