Transactions on Fuzzy Sets and Systems (TFSS), vol.3, no.1, pp.171-183, 2024 (Peer-Reviewed Journal)
Although optimization of weighted objectives is ubiquitous in production scheduling, the literature
concerning the determination of weights used in these objectives is scarce. Authors usually suppose that weights
are given in advance, and focus on the solution methods for the specific problem at hand. However, weights directly
settle the class of optimal solutions, and are of utmost importance in any practical scheduling problem. In this
study, we propose a new weighting approach for single machine scheduling problems. First, factor weights to be
used in customer evaluation are found by solving a nonlinear optimization problem using the covariance matrix
adaptation evolutionary strategy (CMAES) under fuzzy environment that takes a pairwise comparison matrix
as input. Next, customers are sorted using the technique for order of preference by similarity to ideal solution
(TOPSIS) by means of which job weights are obtained. Finally, taking these weights as an input, a total weighted
tardiness minimization problem is solved by using mixed-integer linear programming to find the best job sequence.
This combined methodology may help companies make robust schedules not based purely on subjective judgment,
find the best compromise between customer satisfaction and business needs, and thereby ensure profitability in the
long run.