This thesis deals with real time flow control problems in a flexible manufacturing cell which operates in a stochastic environment.;Depending on the part requirement pattern, the corresponding cell performance criterion changes. For a cell with requirement pattern one, meeting due dates will be most important, whereas for a cell with requirement pattern two, maximization of throughput rate will be an important criterion. When a cell has requirement pattern three, minimization of stock-out cost will be an important issue. These three part requirement patterns and corresponding cell objectives are commonly encountered in today's automated manufacturing. Operation of a flexible cell under different requirement patterns requires different flow control methodologies, and these flow control methodologies are quite different from those used for conventional shop operation.;This thesis identifies three different control models according to the cell objectives and then provides a different flow control methodology for each of the three cell objectives using real time control. For a cell with requirement pattern one, the basic approach adopted in this thesis is to develop a state-based dispatching rule that can be applied locally using real time status information. The basic approach for a cell with either requirement pattern two or requirement pattern three is the discretization of time into small control intervals. Within each interval, induction control and dispatching control are based on optimization models, assuming no major cell status changes within the control period. All three distinct flow control methodologies are based on real time cell information. The three cell control methodologies are evaluated using discrete simulation models, with comparisons to the best available alternative control methods. Based on limited experimentation, the three control methodologies are judged to perform well. (Abstract shortented with permission of author.).;There are three basic requirement patterns that are imposed upon a flexible cell operation. Pattern one is for a cell where specific jobs are required by their due dates. Pattern two is for a cell where part requirements must be satisfied at the end of each time bucket. Pattern three is for a cell where part requirement comes in a certain ratio.
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