Zoning Constrained Machine Layout Problem with Mutual Clearances

Document Type : Article


1 Industrial Engineering/Engineering Faculty/Sakarya University/Sakarya/Turkey

2 Sakarya University


A single row machine layout problem is studied with zoning
constraints and mutual clearances under an enhanced objective of
minimizing material flow cost and machine installation cost. The problem is
restricted by positive and negative zoning constraints to represent real
life problems. Moreover, clearances needed between machine pairs are
divided in to two types, which are must and extra clearances, and extra
clearances are reduced by mutual use between adjacent machines to
decrease material flow costs. Objective function also considers machine
installation cost which usually neglected in machine layout problems in
literature but a necessity in real life problems. Two mathematical models
are formulated, which are nonlinear and linear mixed integer programs, to
solve the problem optimally and to compare the effect of
linearity/nonlinearity in mathematical programming formulations in terms
of solution quality and time. The mathematical models are not effective
in terms of time for large problem instances, therefore a genetic
algorithm is proposed generating high quality solutions in reasonable
time. Effectiveness of the algorithm is revealed by solving several
problem instances and a sensitivity analysis is performed for genetic
algorithm parameters. The cost reductions by means of considering machine
installation costs and mutual clearances are also presented.