# Effect of Dummy Machines in the Gupta’s Heuristics for Permutation Flow Shop Problems

VIT University

^{1}01 Jan 2012-pp 391-398

TL;DR: This paper deals with improving the make span in an FSP using the concept of Dummy Machine in Gupta’s Heuristics to get two more sequences having make spans that may be optimal/near optimal.

Abstract: Optimizing the Make Span is one of the important performance parameters in a flow shop scheduling problem (FSP). The problem is NP hard. In a general Permutation FSP, the total number of possible sequences is (n!). The job for a shop floor supervisor is that he has to schedule the jobs such that the total processing time is minimum. In the shop floor, due to limited computing facilities and capabilities, still the classical heuristics are popular as they are simple and easy to compute manually for smaller problems. However, in many cases, we get only one sequence. This paper deals with improving the make span in an FSP using the concept of Dummy Machine in Gupta’s Heuristics. In such cases, we can get two more sequences having make spans that may be optimal/near optimal. The effect of dummy machine is analyzed using the well-known Taillard benchmark problems.

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RAND Corporation

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