Study on the Optimization of Hub-and-Spoke Logistics Network regarding Traffic Congestion
Algorithm 1
Mutational particle swarm optimization.
Step 1: initialization—setting the values of and the maximum number of iterations . Generate the original population and calculate the fitness of individuals in the population , record the and ,, keep the value of , and meanwhile randomly generate the corresponding new individuals that obtain .
Step 2: If the number of iterations is equal to , turn to Step 5; otherwise, turn to Step 3.
Step 3: The population evolves according to formulae (26) and (25); calculate the individual fitness .
Step 4: compare and . If , modify to generate a new . If the value of is better than , use to save ; meanwhile randomly generate the corresponding individuals that obtain . Otherwise, turn to step 2.
