Research On Emewgency Rescue Route Selection Based On Cumulative Prospect Theory

With the continuous expansion of the city scale,the contradiction between supply and demand of urban traffic is prominent.When various natural or human factors lead to emergencies,scientific and rational selection of emergency traffic rescue route is of great significance for improving the efficiency of emergency traffic rescue and ensuring the safety of people’s lives and property.The random distribution of urban road network in time and space leads to its high degree of uncertainty.A large number of studies have proved that the cumulative prospect theory has certain applicability to the problem of route selection under uncertain conditions.Based on the cumulative prospect theory,considering that decision makers are not fully rational under the conditions of risk and uncertainty,this paper studies the emergency rescue route selection under emergencies,and provides a reliable and effective theoretical basis for the corresponding management departments.Firstly,combining domestic and abroad current research status,starting from the definition and characteristics of emergencies,this paper analyzes the impact of emergencies on urban traffic from three aspects: road facilities,road network structure and traffic control,according to emergency vehicles.According to the driving characteristics of emergency vehicles,the influencing factors of emergency rescue routeselection under normal conditions and emergencies are analyzed respectively.Secondly,by comparing the cumulative prospect theory with the expected utility theory,and based on previous research results,the applicability of the cumulative prospect theory in route selection is demonstrated.Then based on the cumulative prospect theory,the route selection model of emergency rescue vehicles is established.According to the characteristics of emergency traffic,the multi-reference point of the cumulative prospect theory is extended.The travel time and traffic volume are proposed as two heterogeneous references point,the weight function of the model is determined by the personal subjective probability of the decision maker,and the relationship between α and foreground value is analyzed through a simple network.Further considering that due to the influence of various uncertain factors in the actual driving process,the decision-makers’ route selection is usually dynamic.Therefore,based on the risk appetite of the decision-makers,a dynamic path selection model of emergency rescue based on cumulative prospect theory is constructed,and the algorithm of the model is given.The model is verified by a simple network.Then,an example is given to compare the cumulative prospect theory with the expected utility theory.The results show that the cumulative prospect theory is more in line with the actual decision-making behavior of decision makers.Finally,taking the actual road network near Shenyang Olympic Sports Center as an example,44 nodes of the road network and four medical emergency points were selected to simulate the simultaneous occurrence of large-scale fire and a major road traffic accident.The model established in this paper calculates the optimal path from each medical emergency point to each incident point,verifies the validity of the model,and provides an important reference for the relevant emergency decision-makers to plan the route of emergency vehicles reasonably.