摘要:

Efficient sequencing of a mix of end-products in a final assembly shop is particularly well suited for a pull manufacturing environment, such as just-in-time (JIT). Since each product imposes different requirements on the feeder shops, in terms of parts' production, the feeder shops are driven by the sequence of final assembly. We developed a mathematical model and an algorithm for the final-assembly sequencing (FAS) problem. Our model links the FAS problem to smoothing the work-in-process levels of parts in the feeder shops. We designed an efficient local search procedure, based on selective pairwise interchanges, to solve a lexicographic minimax formulation of the FAS problem. Extensive testing revealed that the algorithm consistently provided excellent results in a tractable running time.

ISSN:0020-7543    

DOI:10.1080/00207548908942542

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

An algorithm for the near real-time dispatching and routing of multiple products in a Flexible Assembly System (FAS) environment, called schedule, was described in an earlier paper. This paper presents extended test conditions and results associated with the use of schedule over the test conditions. The extended testing includes results on algorithm performance for larger and more complex assemblies, larger workloads, parametrization on the urgency factor setting in schedule randomization of job due-dates, and a distribution of the job release dates for the workloads assigned to the FAS.

ISSN:0020-7543    

DOI:10.1080/00207548908942543

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Fluidized-bed fixturing systems have recently emerged as one of the significant solutions to the insatiable demand for viable flexible fixturing systems for incorporation in modern computer-integrated manufacturing environments. Herein, viable CAD tools are developed to predict the performance of these fixturing systems under different loading conditions associated with various manufacturing processes such as metal cutting, assembly, etc. In particular, workpiece-fixture interactions in a compacted fluidized-bed fixture are considered for axial, lateral and torsional loading conditions, which may be superposed to effectively represent a general three-dimensional loading condition imposed by a typical manufacturing operation.

ISSN:0020-7543    

DOI:10.1080/00207548908942544

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Research into alternate routings suggests that basing process plans solely on machine and expected batch characteristics may be ignoring two important elements. (1) As actual batch quantities vary from their expected values, the balance between fixed and variable process components sometimes shifts, causing different machines to exhibit lower total processing costs. (2) As the most cost-effective machines become disproportionately loaded, the efficiency of the system may be served by considering alternative machines that are more generally available. The focus of this study is to investigate the significance of considering actual process quantity and relative resource availability under common conditions.

ISSN:0020-7543    

DOI:10.1080/00207548908942545

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

In this paper, an analysis of multiple projects-multiple resources-constrained scheduling problems is presented. A multi-objective management perspective has been used to arrive at schedules for the best utilization of scarce resources. The analysis is accomplished by means of two familiar techniques such as integer goal programming and simulation. Both the techniques are compared by studying some real-life construction projects. Multiple performance measures are used to establish the validity of each technique and also to set directions for project managers to select situation-based technique.

ISSN:0020-7543    

DOI:10.1080/00207548908942546

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The intention of this paper is to develop a framework in order to compare various concepts in production control. It encompasses specific versions of the concepts of Statistical Inventory Control, Manufacturing Resource Planning with safety stocks, Manufacturing Resource Planning with overplanning, Just-In-Time and Optimized Production Technology. This framework will hopefully serve to simplify answers to the important question: ‘Which concept fits which production situation? ’ The development of this framework starts with an abstract description of the production situation in terms of a number of characteristics. Next a suitable choice of performance indicators is specified. The selected characteristics are converted into measurable representative variables. Some conjectures about dominance regions for control concepts are indicated. These conjectures are to be verified by simulation experiments in the near future.

ISSN:0020-7543    

DOI:10.1080/00207548908942547

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

A heuristic algorithm for solving the quadratic assignment formulation to the plant layout problem is presented. The algorithm involves deriving an initial assignment of departments to sites (a construction phase) and then, possibly, improving the solution through exchange between pairs of departments. A ‘classical’ numerical example is used to demonstrate the effectiveness, costwise and in terms of computational effort, of the algorithm. Finally, a set of examples previously used by various authors is assembled and solved in the Appendix. Results are compared to optimal solution values and to the average solution of another known heuristic. These examples could serve as a sample set for testing the effectiveness of other approaches to this problem.

ISSN:0020-7543    

DOI:10.1080/00207548908942548

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Just-in-time production systems are gaining tremendous popularity in modern production environments. Based on the concept of producing exactly the required quantity and type of products, these systems display an excellent ability to adapt to changes in demand as well as permitting greatly reduced work-in-process inventories.

ISSN:0020-7543    

DOI:10.1080/00207548908942549

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

In this paper we examine the direct use of cost/profit information in random and flow shops where early shipments are forbidden. The ‘forbidden early shipment’ environment is typical of many JIT situations, since vendors must deliver parts on their due dates, not before. Hence an order finishing early must be held in a finished-goods inventory until its shipment date. Therefore managerial policies are needed which finish jobs right on time, neither early nor late. This paper looks at value-based and time-based priority scheduling rules and examines the performance of these rules in money terms, as well as by earliness and tardiness measures. Overall, the results show that forbidding early shipments has a major impact on the performance of the value rules proposed in our earlier research.

ISSN:0020-7543    

DOI:10.1080/00207548908942550

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

ISSN:0020-7543    

DOI:10.1080/00207548908942552

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor