Selection of optimal emergency rescue route based on improved ant colony algorithm

The optimal path problem has always been the research core of city emergency rescue. Its research goal has developed from looking for “the shortest path” to searching “the optimal path”. The related algorithms differ in different circumstances. In addition to distance problem, the influence of various practical factors should also be considered under the complicated actual conditions. An improved algorithm is proposed based on the basic ant colony algorithm model, directing at its weakness of slow convergence and stagnation behavior etc. The improved algorithm used the idea of limiting pheromone range of max-min ant colony algorithm for reference to inhibit the stagnation behavior caused by aggregative gap between the shortest path information and the longest. The introduction of partial pheromone update and search strategy has effectively controlled the premature phenomenon and speeded up the solution. Meanwhile, the algorithm´s mathematical model and the methods of parameters combination were improved considering the various sorts of uncertain factors that influence the choice of the optimal path, such as weather, road quality, road condition, vehicle speed etc. in order to obtain a more appropriate driving path in practical condition.