Tabu search approaches for the multi-level warehouse layout problem with adjacency constraints

Abstract

A new multi-level warehouse layout problem, the multi-level warehouse layout problem with adjacency constraints (MLWLPAC), is investigated. The same item type is required to be located in adjacent cells, and horizontal and vertical unit travel costs are product dependent. An integer programming model is proposed to formulate the problem, which is NP hard. Along with a cube-per-order index policy based heuristic, the standard tabu search (TS), greedy TS, and dynamic neighbourhood based TS are presented to solve the problem. The computational results show that the proposed approaches can reduce the transportation cost significantly.

Keywords:

• warehouse layout
• multi-level
• tabu search
• adjacency constraints

Acknowledgements

This research is supported by an NSERC Discovery grant and CFI funding.