A Metro Freight Plan for Mixed Passenger and Freight Transportation

Algorithm 3

Procedure of VND

(i)	Step 1: Enter the initial solution and neighborhood structure set of the VND, go to Step 2.
(ii)	Step 2: Let until , and then go to Step 3.
(iii)	Step 3: Use the neighborhood structure to perform a local search to generate a new solution , and then go to Step 4.
(iv)	Step 4: If , it means that is better than the current optimal solution , then let and continue to search within the current neighborhood structure (); otherwise, let . Meanwhile if , go to Step 5; otherwise, go to Step 3.
(v)	Step 5: Until the termination criterion is met, the optimal solution is returned.