Performance analysis of flow lines with non-linear flow of material
The book under review deals with some of the problems of manufacturing systems with special reference to random disruptions in the flow of material from one work station to another. The material is divided into six chapters and two appendices: Introduction. Issue. Goals and Methods of Flow Line Analysis. Assembly/Disassembly of Systems with random processing times. Flow Lines with Rework Loops and Machine-specific processing times. Conclusions and suggestions for further research: Appendices: A: Derivation for the discrete material flow line. B: Derivation for the continuous material flow line. Bibliography. The author, perhaps rightly, places emphasis on the development of analytical tools in preference to simulation methods. Each of the chapters is supported by numerical illustrations with appropriate inference of algorithms. Since the two machine line is an appropriate unit of the larger assembly and exhibits most of the salient features of the assembly of which it is a part, the author has, rightly dwelt at great length the problem of two machine subsystem. To facilitate the analysis the author has imposed suitable constraints on the processing time, time to failure and time to repair resulting in the Markov behaviour of the system. The very complexity is due to the interaction of the two machines; however the very exponential/geometric nature of the distributions of the various time spans makes the analysis elegant and leads to the determination of the expected value of the cost. Using these results the author is able to present the realistic picture of the assembly as a whole. The bibliography is extensive and the author has taken pains to make the literature survey complete in all respect. The reviewer is of the opinion that the assumption of exponential character for the distribution of various time spans is too much of a simplification and may not be appropriate for real life problems. It could have been nice if the author has avoided the path of least resistance and explore the possibility of analysis of the basic two machine unit when at least one of the random times does not obey exponential/geometric distribution. Had he done so he would have realised the richer theory of renewal/regenerative stochastic processes would have still made the analysis look elegant and at the same time would have let to a more general method of estimating the cost functions. Neverthless the book is of considerable interest to assembly operation designers, OR analysts and management scientists in general. Applied probabilists will also find the book interesting.
scientific article; zbMATH DE number 1344815