Capacity Oriented Analysis and Design of Production Systems

ISBN-13: 9783540506928 / Angielski / Miękka / 1989 / 245 str.

M.B.M. de Koster

Opis

In production systems there are often capacity oriented performance objectives, like a desired total throughput, a desired average throughput time and average work in-process. Such performance objectives are expressed in "units of products" rather than in specific product types. This book presents a way of modeling and analyzing production systems so, that such capacity oriented performance criteria can be measured in a simple way. The model consists of three basic elements. 1. The product types in the system are aggregated. 2. The product flow is modeled as being continuous. 3. The machines in the model have a finite number of states. Each state has a phase-type sojourn distribution and an associated production speed. Transitions between the states are determined by an irreducible Markov transition matrix. In the book both the mathematical properties and the practical applicabilities of the model are investigated. The model is extensively analyzed for various layouts, like flow lines, assembly disassembly systems and networks where parallel machines share common buffers. Furthermore various ways of controlling the product flow in the model are investigated, such as Base Stock Control, Workload Control, control by finite buffers and control by the Reorder Point System. An approximation technique is developed for a quick estimation of performance measures like throughput and average work-in-process, for networks with layouts and control techniques like those above-mentioned."

Spis treści

1 Aggregate Control of Production Systems.- 1.1 Introduction.- 1.2 Problem formulation.- 1.3 Capacity control structures.- 1.3.1 Local control structures.- 1.3.2 Integral control structures.- 1.4 Capacity modeling of production systems.- 1.5 Contents of the text.- 2 Capacity Analysis of Two-Stage Lines.- 2.1 Case: an insertion department.- 2.1.1 Case descript ion.- 2.1.2 Modeling the insertion department.- 2.2 Literature on two-stage lines.- 2.3 The two-stage model.- 2.3.1 Introduction.- 2.3.2 Model description.- 2.3.3 Model analysis.- 2.3.4 Solution of the model for ?1?0, ?2?0 and ?1??2.- 2.3.5 Numeric results.- 2.3.6 State-dependent failures.- 2.3.7 Comparison with a discrete product model.- 2.4 More complex machines.- 2.4.1 The model.- 2.4.2 Interpretations of the model.- 2.4.3 Model analysis.- 2.5 Control of the two-stage line.- 2.5.1 Infinite buffers and backlogging.- 2.5.2 Control by switching policies.- 2.6 Analysis of buffer behavior.- 2.6.1 Buffer fluctuations.- 2.6.2 Determination of stock increase and stock decrease moments.- 2.6.3 Relations between buffer stock moments and line characteristics.- 2.7 Approximation of complex two-stage lines.- 2.7.1 Introduction.- 2.7.2 More numeric results.- 2.8 Discrete product models.- 2.9 Analysis of the insertion department.- 2.10 Conclusions and preview.- 3 More Complex Systems.- 3.1 Network layouts and analysis techniques.- 3.2 Literature survey.- 3.2.1 Literature on N-stage lines.- 3.2.2 Literature on general layouts.- 3.3 N-stage lines.- 3.3.1 The N-stage continuous flow line.- 3.3.2 Analysis of three-stage lines.- 3.3.2.1 Two machines perfect, one machine unreliable.- 3.3.2.2 More than one machine unreliable.- 3.3.3 Three-machine assembly-disassembly networks.- 3.4 Reversibility of production networks.- 3.4.1 Reversibility in assembly-disassembly networks.- 3.4.2 Buffer-sharing networks.- 4 Analysis of Locally Controlled Systems.- 4.1 Aggregation of two-stage lines.- 4.2 Approximation of flow lines.- 4.2.1 Approximation method 1.- 4.2.2 Approximation method 2 for three-stage lines.- 4.2.3 Method AP2 for N-stage lines.- 4.3 More numeric results and comparisons.- 4.4 Other network layouts.- 4.4.1 Approximation of assembly-disassembly networks.- 4.4.1.1 Networks with a single a/d machine.- 4.4.1.2 Numeric results.- 4.4.2 Buffer-sharing networks.- 4.5 Other types of local control.- 4.6 Discussion.- 5 Analysis of Integrally Controlled Production Systems.- 5.1 Control with the Base-Stock System.- 5.1.1 Model description.- 5.1.2 Approximation by locally controlled lines.- 5.1.3 Additional local restrictions.- 5.2 Approximation of workload-controlled lines.- 5.3 Discrete-product models.- 5.4 Nonstationary behavior and conclusions.- 6 Capacity Modeling of Multiproduct Lines.- 6.1 Aggregates instead of items.- 6.2 Lot-sizing.- 6.3 Work-in-process.- 6.4 Nonstationarity.- 6.5 Conclusions.- 7 Case Studies.- 7.1 A coin-validator production line.- 7.1.1 Case description.- 7.1.2 Design problems.- 7.1.3 Control structure.- 7.1.4 Problems involving operators.- 7.1.5 Modeling the coin-validator line.- 7.1.6 Model analysis.- 7.1.7 Discussion of results.- 7.2 A differential gear factory.- 7.2.1 Case description.- 7.2.2 Control objectives.- 7.2.3 Modeling the case.- 7.2.4 Control of the aggregate flow in the model.- 7.2.5 Analysis of the model.- 7.2.6 Evaluation.- Epilogue.- Appendix A.- Appendix A. 1.- Appendix A. 2.- Appendix A. 3.- Appendix B.- Appendix C.- Appendix D.- References.- Glossary of Notations.