Dynamic optimization of the operation of single-car elevator systems with destination hall call registration: Part II. The solution algorithm

In this study we consider the elevator operation problem of single-car elevator systems with destination hall call registration. In this part we construct a branch-and-bound algorithm to solve the dynamic operation optimization problem formulated in the first part. To calculate lower bounds of the subproblems generated in the course of the branch-and-bound algorithm, we first relax some of the constraints of the subproblems and decompose the relaxed subproblems into three parts. Then, we apply the Lagrangian relaxation method to the decomposed subproblems.