Batch scheduling duling of incompatible jobs on a single reactor with dynamic arrivals

Korkmaz, Gediz
In this study, a single machine batch-scheduling problem with incompatible jobs and dynamic arrivals is examined. The objective function is the minimization of the total flow time of the jobs. For solving problems a case specific branch and bound algorithm with a heuristic upper bound scheme and two alternative lower bound procedures is used. An extensive computational experiment is conducted to investigate the effects of certain parameters on the computation time. For the most difficult parameter combination branch and bound algorithm can solve the problems about 25 jobs with 4 different job types in a 10 minutes time on average. For the problem types with higher number of jobs and the most difficult parameter combination proposed upper bound heuristic can be used to obtain near optimal solutions.


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In this study, non-permutation flowshops with missing operations are considered. The primary performance criterion is the total cycle time (i.e. makespan) and the secondary criterion is the total flowtime. In order to obtain the schedule with minimum makespan and minimum total flowtime, non-permutation schedules are being generated instead of permutation ones by permitting multiple jobs bypassing stages where misisng operations occur. A heuristic algorithm has been developed in order to generate non-permuta...
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In today's conditions, systems that surround individuals have evolved in structure such that, nature of variable interactions are much more complex and changing continuously. Logistics systems, which constitute an example for such systems, have also necessitated fast management and decision-making in a fast paced environment, under limited sources with the additional effect of increasing customer requirements and competition. In this study, system dynamics approach was shown to be a competent alternative to...
Citation Formats
G. Korkmaz, “Batch scheduling duling of incompatible jobs on a single reactor with dynamic arrivals,” M.S. - Master of Science, Middle East Technical University, 2004.