This paper considers a single-machine scheduling problem in which penalities occur when a job is completed early or late. The objective is to minimize the total penalty subject to restrictive assumptions on the due dates and penalty functions for jobs. A procedure is presented for finding an optimal schedule.

We evaluate operations management–related journals based on a novel indicator of journal quality—the Author Affiliation Index (AAI). We explain the basic rationale behind the AAI, as well as its advantages and disadvantages with respect to other such indicators of journal quality. We provide a specific recipe for its calculation and apply it to 27 journals in which researchers in the field of operations management might wish to publish. We compare the resulting journal rankings to those from published survey reports and citation analyses and test AAI for sensitivity to its inputs. We find the rankings from AAI to be consistent with other studies and to be robust with respect to changes in inputs.

In the context of production scheduling, inserted idle time (IIT) occurs whenever a resource is deliberately kept idle in the face of waiting jobs. IIT schedules are particularly relevant in multimachine industrial situations where earliness costs and=or dynamically arriving jobs with due dates come into play. We provide a taxonomy of environments in which IIT scheduling is relevant, review the extant literature on IIT scheduling, and identify areas of opportunity for future research.

EXECUTIVE SUMMARYThis paper introduces a new dispatching rule to job shop scheduling, extending earlier results to a multi-machine environment.

This paper addresses the problem of n jobs to be scheduled on a single machine in such a way that flow time variation is minimized. When the measure of variation is total absolute difference of completion times (TADC) the problem is shown to be quite simple. Sufficient conditions are shown for minimal TADC and a simple method for generating an optimal solution is provided. When the measure of variation is variance of flow time the problem is much more difficult. For this case a heuristic method for scheduling is proposed. The heuristic is simple and provides solutions which compare favorably with others found in the literature.production/scheduling: flow shop, programming: heuristic

We address a single‐machine scheduling problem in which penalties are assigned for early and tardy completion of jobs. These penalties are common in industrial settings where early job completion can cause the cash commitment to resources in a time frame earlier than needed, giving rise to early completion penalties. Tardiness penalties arise from a variety of sources, such as loss of customer goodwill, opportunity costs of lost sales, and direct cash penalties. Accounting for earliness cost makes the performance measure nonregular, and this nonregularity has apparently discouraged researchers from seeking solutions to this problem. We found that it is not much more difficult to design an enumerative search for this problem than it would be if the performance measure were regular. We present and demonstrate an efficient timetabling procedure which can be embedded in an enumerative algorithm allowing the search to be conducted over the domain of job permutations.© 1993 John Wiley & Sons, Inc.

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This report examines the practice of using work load limits to control the release of orders to a job shop. Load limits function in the following general way. Whenever the inventory of work at a work center exceeds some critical value (its “load limit”), further release of orders which are routed to that work center are blocked from entering the shop. After the inventory is “worked off,” release of work to the shop gateways is again permitted. Load‐limited order release is intuitively appealing because it appears to be a method for reducing system inventory and flow times. The practice of load limiting order release is becoming popularized by some of the recent production planning software products now on the market. A notable example is OPT. In this report, analytical results for an M/M/1 queueing model, along with existing simulation studies of multi‐machine job shops are interpreted to form a theory about the effects of using load limits.The major finding here is the proposition that system flow time, inventory, and order tardiness all deteriorate to the extent that load limits introduce idle time into the schedule. Based on the arguments presented here, a very cautious approach toward the use of input control schemes for anywhere but gateway work centers would be advised. The conclusions drawn here are to a great extent arrived at by interpreting the research results of others, so there is a clear need for further research which tests these assertions in a more direct and controlled way.