Abstract:

In order to realize scientific and efficient post-disaster transfer of the population after the occurrence of major natural disasters, the emergency bus evacuation planning considering the transfer urgency was studied according to the different severity of the disaster. Firstly, a continuous emergency bus evacuation model was established with the goal of minimizing the evacuation completion time and evacuation delay satisfaction degree. Secondly, a HS-GA based on transfer urgency coding was designed and applied for problem-solving, and the effectiveness of the algorithm was verified using examples of different scales. Finally, the evacuation planning considering the transfer urgency was compared with those without considering the transfer urgency based on the case. The results show that the HS-GA is better than Genetic Algorithm (GA) and Neighborhood Search GA (NS-GA). According to the case solved by HS-GA, a comparison is made with evacuation planning that does not consider transfer urgency. When transfer urgency is considered, the evacuation delay dissatisfaction degree is reduced by 51.4%. Additionally, shorter evacuation completion times are observed at both Class I and Class II disaster sites. The average time taken to arrive at the shelter is also found to be shorter. At the same time, the dissatisfaction degrees of evacuation delay considering the urgency of transfer under different emergency bus quantity are all lower. The evacuation model considers the evacuation priority of the hard-hit areas under different severity of the disaster, and can make reasonable dispatch arrangements under the circumstance of limited rescue vehicles, which is more objective and in line with the actual situation.

Key words: emergency bus, evacuation planning, transfer urgency, harmonic search genetic algorithm (HS-GA), evacuation delay dissatisfaction degree