Gharehgozlii - Department of Industrial Engineering, Faculty of Engineering, University of Tehran
Tavakkoli-Mogahddamii - Associate professor, Department of Industrial Engineering, Faculty of Engineering, University of Tehran
Zaerpour - Department of Industrial Engineering, Faculty of Engineering, University of Tehran

This paper presents a new mixed-integer goal programming (MIGP) model for a parallel machine scheduling problem with sequence-dependent setup times and release dates. Two objectives are considered in the model to minimize the total weighted flow time and the total weighted tardiness simultaneously. Due to the complexity of the above model and uncertainty involved in real-world scheduling problems, it is sometimes unrealistic or even impossible to acquire exact input data. Hence, the researchers consider the parallel-machine scheduling problem with sequence-dependent set-up times under the hypothesis of fuzzy processing time's knowledge and two fuzzy objectives as the MIGP model. In addition, a quite effective and applicable methodology for solving the above fuzzy model is presented. Finally, the effectiveness of the proposed model and the denoted methodology is demonstrated through some test problems.

parallel mahine scheduling; mixed-integer goal programming; fuzzy theory; sequence-dependent setup time; release date