Emergency supplies distributing and vehicle routes programming based on particle swarm optimization

Fuzzy demands,dynamic transportation network,and prioritized supplying and distribution are the typical characters of emergency supplies under eruption incident(s).Making use of the triangular fuzzy numbers of fuzzy mathematics to describe the emergency demands for supplies,and the speed of time-dependent function to simulate the real dynamics states of the road network,as well as thinking of the prioritized condition,the paper set up an optimization model for scheduling emergency supplies, which had a multi-objective and could choose a road to avoid congestion in special period of time,and strictly meet the needs of time requirement of the real supply orders.Then a Particle Swarm Optimization algorithm has been designed according to the characteristics of the model.A vector encoding method with"discrete-continuous variables encoding"for every particle was put forward,a Fitness Function was proposed according to the objective functions,a strategy for continues renewing the location and velocity of each particle was proposed.It could better solve the problems of discrete and continuous combinatorial optimization variables for the mathematical model of the emergency dispatch.With the help of an empirical analysis in combination with two examples,the algorithms was proved suitable and validity when the direct comparison of exact solutions obtained by the MATLAB was done.