Comparative Study Between Crisp and Fuzzy Solutions for Job- Shop Scheduling Problems
نویسنده
چکیده
Optimizing jobshop-scheduling problems (JSSPs), in wh ich imprecise processing times are modeled as fuzzy numbers, results in more flexible solution. That is, the produced schedule is flexible; it stays valid and can cope with all possible durations within the specified range. In this paper, we present evidences that support the claim that solving JSSPs with fuzzy processing times would produce schedules less sensitive to variations in processing times. Empirical evidence is introduced to show that optimal solutions of the crisp JSSPs seem more sensitive to the variations in processing times than the optimal solutions of the fuzzy JSSPs. Therefore; optimizing fuzzy JSSPs cannot be reduced to optimizing crisp JSSPs. To show this, three different benchmark problems, FT 6x6, La11, and La12 were tested using their crisp and fuzzy processing times.
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