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This paper considers the application of cellular manufacturing (CM) to batch production by exploring the shop floor performance trade-offs associated with shops employing different levels of CM. The literature has alluded to a continuum that exists between the purely departmentalized job shop and the completely cellular shop. However, the vast majority of CM research exists at the extremes of this continuum. Here, we intend to probe performance relationships by comparing shops that exist at different stages of CM adoption. Specifically, we begin with a hypothetical departmentalized shop found in the CM literature, and in a stepwise fashion, form independent cells. At each stage, flow time and tardiness performance is recorded. Modeling results indicate that, depending on shop conditions and managerial objectives, superior shop performance may be recorded by the job shop, the cell shop, or by one of the shops between these extreme points. In fact, under certain conditions, shops that contain partially formed cells perform better than shops that use completely formed cells. Additional results demonstrate that in order to achieve excellent performance, managers investigating specific layouts need to pay especially close attention to changes in machine utilization as machine groups are partitioned into cells. [ABSTRACT FROM AUTHOR]

We present a framework for managing vital customer priorities in job-shop manufacturing environments. We introduce the notion of attaining near-perfect on-time delivery service to a small portion of the firm's customers who contribute to a substantial portion of its sales revenue and profits. Consequently we postulate that appropriate order review and release (ORR) policies, along with the dispatching rules used to schedule customer orders, can be combined effectively to achieve the desired customer service results. Several dispatching rules specifically designed for this study are tested under different operating environments in order to derive the recommended set of ORR and dispatching rule policies. Capacity-based ORR procedures, in conjunction with dispatching rules that pace a job's progress through different operations in its route, provide the best overall performance. The nature of trade-offs inherent in managing the priorities of vitally important customers are also identified and presented in the form of managerial recommendations that can be used to enhance a job shop's overall performance. [ABSTRACT FROM AUTHOR]

We investigate the performance of capacity-sensitive order review and release (ORR) procedures in job shop environments that have not been previously explored. Previous research has ignored the case of job shops which must perform to very tight due-dates because of time-sensitive customers! We propose and test a new capacity sensitive ORR procedure called path based bottleneck (PBB) in such environments, along with the modified infinite loading (ML) procedure which has been shown to work well in several studies. We compare the performance of these two controlled release rules with that of immediate release rule under different conditions of capacity utilization and customer specified exogenous due- dates. Our results indicate that PBB performs well in lowering total costs when due-dates are fight, while MIL is a better procedure with relatively loose to medium due-dates. We also show that in many cases, the shortest processing time (SF1) dispatching rule is a superior performer than a due-date based rule like critical ratio (CR); a conclusion which is contrary to the existing research in this area. In addition, the shop floor control policies recommended are shown to be sensitive to the cost structure of the firm. The managerial implications of this research in providing effective shop floor control in job shops operating under fight due-date conditions are also discussed. [ABSTRACT FROM AUTHOR]