Three-level AHP-based heuristic approach for a multi-objective facility layout problem

In real decision making problems, many conflicting objectives have to be taken into account. With increasing awareness of this, multi-objective problems have become more and more popular. Similarly, the design of the multi-objective facility layout problem (MOFLP) has generally been recognised as an important issue in the modern manufacturing system. The MOFLP is formulated as a quadratic assignment problem (QAP) which is NP-hard and solving MOFLP is a tough problem. A new three-level AHP-based heuristic algorithm for resolving the MOFLP is presented here. It also presents a new normalisation procedure (H-1), and a new heuristic method (H-2) for generating objective weights. The proposed approach consists of three levels. The first level applies AHP to generate paired comparison matrices, the consistency of matrix, to convert inconsistent matrices into consistent ones and then generate a qualitative objective matrix; the second level applies normalisation procedure (H-1) to normalise matrices of qualitative and quantitative objectives and the third level computes the objective weight for qualitative and quantitative objectives. An illustrative example is shown to demonstrate an application of the proposed methodology for solving MOFLP.