Suchergebnisse

Presents a framework to determine manufacturing planning and
control system requirements that reflect differences in manufacturing
strategy and process technology in a business. Manufacturing planning
and control systems represent a critical part of the manufacturing
infrastructure and support functions, and their design needs to be
closely linked to decisions regarding a firm′s manufacturing strategy
and choice of processes. Discusses examples of companies which have
developed a good fit between their manufacturing planning and control
systems and their manufacturing strategy in terms of the framework
presented.

Describes an integrative microcomputer‐based exercise, ITEC, used
in teaching manufacturing strategy and manufacturing planning and
control courses. The exercise allows students the opportunity to gain
actual experience in making strategic decisions in manufacturing and in
managing the flow of materials in complex operations. It gives students
experience in making process choice decisions, and reinforces their
understanding of the difference between the planning and execution
decisions necessary to manage manufacturing operations using MRPII
planning logic under dynamic conditions. It provides experience in
managing both batch and line operations and is useful in demonstrating
the introduction of Just‐in‐Time manufacturing. The exercise also
provides experience in scheduling and co‐ordinating vendor operations to
support manufacturing requirements. Because of the uncertainty in
customer demand, process yields and vendor deliveries, students gain
insight and facility in managing complex operations with imperfect
information. Outlines the structure of ITEC, its educational benefits,
and its application within undergraduate, masters and executive
education classes.

ABSTRACTManaging the trade‐off between achieving a stable master production schedule (MPS) and being responsive to changes in customer requirements is a difficult problem in many firms where providing a high level of customer service is viewed as an important competitive factor. One alternative for managing this trade‐off is to freeze an agreed portion of the MPS. This paper investigates the impact of adjustments in the design parameters of MPS freezing methods on two performance measures (MPS lot‐sizing cost and stability) under stochastic demand conditions in a rolling planning horizon environment given a service level target. Simulation experiments are reported which indicate that many of the conclusions regarding the design of MPS freezing methods obtained under deterministic demand conditions hold under stochastic demand.

Narasimhan and Wang (2000) provide a valuable addition to the research base by identifying a limitation in two of the original equations in Bozarth and Berry (1997), which we resolve, and a possible research direction for the calibration of indifference profiles. However, they fall short in their interpretation of key conceptual and methodological issues, including the distinction between indifference and ideal profiles, the difference between individual profile dimensions and overall congruence, and firm versus industry‐level manufacturing strategy research. We use this opportunity to clear up these points of confusion, and to reaffirm the value of the methodology introduced in Bozarth and Berry (1997).

ABSTRACTThis paper presents a measurement methodology, based on existing research in the manufacturing strategy and general strategy areas, for evaluating the congruence between market needs and manufacturing plant capabilities. The proposed methodology has several important advantages over current approaches. First, the methodology uses available data and statistical techniques to measure market‐manufacturing congruence. As a result, it is not dependent on assumptions about "classic" process choices. Second, the proposed methodology can evaluate the strategic fit between market needs and manufacturing in light of one or more performance criteria. Third, the methodology can be used to derive scalar measures of market‐manufacturing congruence, allowing users to evaluate congruence for a large number of products, customers, or market segments.The theoretical basis, research objectives and major steps of the methodology are discussed, followed by an illustrative example from a North American manufacturer. Finally, the applicability of the methodology to a wide range of strategic manufacturing decisions is discussed.

ABSTRACTThis paper presents a branch and bound algorithm for assigning men to machines in a production system. The labor assignment problem of concern in this paper occurs when 1) a single operator can service several semi‐automatic machines simultaneously, 2) the service and machine processing times are different among the machines and are deterministic, 3) a strict cyclic service discipline is assumed, and 4) the combined costs of idle labor and machine time are to be minimized. The paper includes a formal definition of the labor assignment problem, a description of the branch and bound algorithm, and a discussion of the computational experience with the algorithm.

ABSTRACTA branch and bound algorithm is presented for determining the minimum number of telephone operators, and their shift schedules, required to meet demand that varies over a 24 hour operating period. An integer linear programming formulation is used, and the algorithm is described in terms of its separation, relaxation, fathoming, and branching procedures. Computational results are provided, using actual operating data. The results indicate that practical sized problems can be solved by the algorithm, involving as many as 100 different shift type variables and demand profiles typical of those encountered in many telephone traffic exchanges.

ABSTRACTMaintaining a stable master production schedule (MPS) is difficult for many firms, especially when material requirements planning is used to manage production operations. This paper is concerned with the problem of measuring MPS stability, and the impact on stability of three important decision variables in managing the MPS within a rolling‐horizon framework in a make‐to‐stock environment: the method used to freeze the MPS, the proportion of the MPS frozen, and the length of the planning horizon for the MPS. Simulation experiments conducted to determine the impact of these decision variables, as well as other important product demand and cost characteristics, on MPS stability are reported. The results indicate MPS stability can be influenced by managerial action directed toward management of the MPS as well as changes in important product cost and requirements characteristics.

A sample of 63 Danish companies is divided into four strategic groups. Each group represents a distinct manufacturing strategy. These strategic groups are then used to investigate relationships with the implementation of bundles of manufacturing practices such as JIT and TQM, and with operational performance. The results suggest that using strategic groups as a representation of companies' manufacturing strategy can improve the understanding of companies' implementation of bundles of manufacturing practices and of their operational performance. The results indicate that the degree of environmental fit differs amongst the groups and that companies do not necessarily have to conduct an extensive implementation of all bundles of manufacturing practices in order to perform well on important performance dimensions according to their manufacturing strategy. Finally, the study adds to the scarce literature on small country studies.

The basic tasks of a business are straight‐forward – getting
and keeping customers and making profits, both set within the context of
the short and long term. Explicit in these is not only a need for
marketing and manufacturing to work well in themselves but to work well
together. Companies, however, typically fail in this provision. To move
to a more competitive response in today′s difficult markets requires
more than co‐existence, it requires a shared partnership between the
core parts of the firm. Shared understanding of marketing and
manufacturing′s approach is the starting point. The other is building on
a shared understanding of the market itself. In such a way, a move to
being customer‐driven starts to take shape.

This research compares Material Requirements Planning (MRP), Kanban, and Period Batch Control (PBC) as alternative approaches to the planning and control of multi‐cell manufacturing involving flow cells and assembly. Since previous research on performance of these systems in cellular manufacturing has been primarily conceptual, the experiments reported here provide new insights into their comparative performance.The results show that the production environment is a major factor in system choice. Three operating factors—Master Production Schedule (MPS) volume variation, MPS mix variation, and setup time/lot size—clearly affect system choice. All systems performed well under Justin‐Time (JIT) conditions; there was no advantage to Kanban. Under the mixed conditions of high MPS variation, but small setup time/lot sizes, PBC produced superior performance compared to Kanban and MRP. Under non‐JIT conditions, MRP was seen as clearly more effective. Finally, the results indicate that when conditions permit very small lot sizes relative to requirements, Kanban may perform best, even when MPS variation is high.

Reports a new method for preparing a product structure analysis to
improve the effectiveness of the master scheduling function for products
that are manufactured on an assemble‐to‐order basis. This methodology
for conducting product structure analysis uses relational database
management software to identify common and unique material in a product
structure. Highlights example results of the application of methodology.

ABSTRACTThis paper is concerned with planning work‐center capacity levels in manufacturing firms that employ a material requirements planning (MRP) system. It presents four procedures for developing work‐center capacity plans designed to insure the production of components and assemblies as specified by the MRP plan and the master production schedule (MPS). These procedures (capacity planning using overall factors, capacity bills, resource profiles, and capacity requirements planning) are compared using simulation analysis. The results indicate that the performance of a procedure when measured against the MPS depends on the operating conditions of the manufacturing system. The results also indicate that the choice of a particular procedure often represents a compromise among the benefits of improved MPS performance, the costs of preparing and processing data, and the premium expenses required for more frequent adjustments in work‐center capacity levels.

ABSTRACTIn multi‐stage production‐inventory systems, the demand for precursor items derives from the demand for successor items at the later stages in the system. This paper presents a method for evaluating the performance of two different strategies for forecasting the demand for precursor items. The dependent strategy relies on successor item forecasts to build a precursor item forecast, while the independent strategy relies on the extrapolation of past precursor demand. An expression indicating the conditions under which one strategy is preferred to the other is developed, and the effect of changing these conditions is illustrated with simulation results.

1. Perspectives on disaggregation -- 2. Disaggregation in manufacturing and service organizations: survey of problems and research -- 3. Toward a theory of hierarchical coordination and conflict -- 4. An MSA view of disaggregation -- 5. Hierarchical planning systems: a production application -- 6. Optimal aggregation and disaggregation in hierarchical planning -- 7. A hierarchical approach for the planning of a complex production system -- 8. A hierarchical approach to multilocation inventory systems -- 9. A disaggregation problem and a search enumeration algorithm for a multiplant, multiproduct scheduling application -- 10. An efficient algorithm for multi-item scheduling -- 11. Large scale optimization for master production scheduling -- 12. Multi-item scheduling with reflection programming -- 13. An approach to the analysis of integrated production-distribution systems -- 14. Empirical relationships among budgets, other financially-oriented aggregate plans, and the master production schedule (MPS) -- 15. Hedging the master schedule -- 16. The disaggregation problem in the paper industry -- 17. An economic lot size algorithm for multi-level inventory systems with acyclic network structures -- 18. Impact of a product structure measure on the effectiveness of lot sizing techniques -- 19. The effects of joint lot size strategies on capacity related performance in a multi-stage production-inventory system -- 20. The impact of capacity on lot sizing decisions -- 21. Variations in optimizing serial multi-stage production/inventory systems -- 22. Priority updating procedures in dynamic job shop simulation studies: the impact on measures of performance under different due date assignment rules -- 23. A review of flowshop scheduling research -- 24. An aggregate-disaggregate approach to the large scale multiple project scheduling problem -- 25. Shift scheduling for telephone operators and service office employees -- 26. A complete control system for workforce management at a post office -- 27. Decision making in the public sector: an application of goal interval programming for disaggregation in the post office -- 28. Disaggregation of manpower in a service organization -- 29. Facilities planning in the railroad industry: the need for disaggregation -- 30. Vehicle dispatching — sweep algorithm and extensions -- 31. Navy enlisted manpower planning -- 32. A public policy optimization model with simulation of disaggregation aspects: formulation of energy R and D policy -- 33. Costs and benefits of a computer based regional blood inventory system -- 34. Multi-level police patrol planning -- 35. Disaggregation of the decisions to allocate patrol resources to police precincts -- 36. Economically optimal quantity and mix of fire department services -- 37. Disaggregation planning, scheduling and allocation of nursing staff -- 38. 'Disaggregate mathematical models of optimal hospital bed management -- 39. Recursive modeling of outpatient health care settings -- 40. Nurse scheduling: a case of disaggregation in the public sector -- 41. Computerized scheduling of hospital nursing personnel: disaggregation to accommodate individual preferences and nonroutine constraints -- 42. Disaggregating health utilization data for planning -- 43. Scheduling workers in situations having highly variable manpower requirements -- 44. Optimal scheduling of two consecutive work periods -- 45. A simple method for obtaining cyclic employee schedules -- 46. Heuristic work force scheduling with variable shift lengths and labor productivity differences: a case study of encoder staffing.