391

tial equations is assumed and some familiarity with perturbation techniques would be useful.

The book is aimed at the applied mathematician at the advanced under- graduate or graduate level and concentrates on singular perturbat ion prob- lems. These problems are divided into two types: layer-type problems and cumulative-perturbation problems.

The text is comprehensive and is written in five chapters. Chapter 1 is a short introduction and contains some background on asymptot ic expansions, limit process expansions, matching and general asymptot ic expansions. The following three chapters are more substantial. Chapter two deals with the application of limit process expansions to ordinary differential equations: this is achieved by considering a series of examples. In chapter three cumu- lative perturbation problems are tackled using the multiple-variable expansion procedures: again a series of examples is considered and in particular there is a large section devoted to satellite problems. Chapter four applies the methods discussed earlier to partial differential equations, again through a series of examples, including some taken from biology. Finally, chapter five considers in some detail examples taken from fluid mechanics.

There is a considerable number of problems for the student to try, an essential feature of any text-book, but unfortunately answers are not supplied. In addition, there are many references to help the reader to take his studies further. Perhaps this book is too comprehensive for the average undergraduate but it is essential reading for the graduate or research worker in this field and is a useful reference work for the bookshelf.

H. CLARK

Energy Management Principles, by Craig B. Smith, Pergamon, New York, 1981. ISBN 0-08-028036-6, xx + 395 pages, 125 illustrations, hard cover approx. £24.70: paperback (ISBN 0-08-028811-1) US$29.50

This is a rather disappointing book from the pen of a senior engineer of wide experience of energy management in the USA. With a dramatic cover, showing a silhouette of a process plant structure against a vivid yellow back- ground, and approximately 400 pages the book promises a lot but fails to deliver.

Perhaps a major cause of the failure lies in the rather confused objectives of the author. In the Preface he claims to be writing for the "junior, senior or first year graduate engineer" but some 400 pages later the book is for the "senior, graduate or practising engineer or architect". Furthermore, whilst the cover implies an interest in process plant energy management the book is heavily biased towards the HVAC field and specifically USA practices.

The structure of the book and the presentation of the material is difficult to fault, although the insertion of appendices between chapters is rather an irritating feature. Indeed the appendices comprise nearly one seventh of

392

the book, a rather high percentage which could easily have been reduced. The judicious selection of photographs can enhance the presentation of

written material but on this occasion Dr. Smith must have had a bad day. Most of the dozen or so photographs he uses must rank among the most unin- teresting ever taken, for example, a typical HVAC pump (p. 120), a dirty fluorescent tube (p. 191) and a close-up of an electric motor casing (p. 363).

A study of techniques used by primitive man, and even animals, to produce a comfortable environment can provide Modern Man with salutary lessons in the conservation of energy. However, I question the need in a book of this nature to devote four pages to the antics of desert rodents.

This book contains much useful information and good engineering prac- tice but the interests of conservation would have been served much better if the tome had been half its present thickness.

ALAN WRIGHT

Automatic Assembly, by Geoffrey Boothroyd, Corrado Poli and Laurence E. Murch, Marcel Dekker, New York, 1982. ISBN 0-8247-1531-4, viii + 378 pages, illustrated, hard cover Sfr. 135.00.

This book is a welcome return to print of the earlier "Mechanised Assembly" with revisions, updating and extensions in the automatic assembly field to justify its new title of "Automat ic Assembly".

This is perhaps the only analysis of performance of the various widely- used means of automated assembly and it is invaluable for an understanding of the principles of automation. Featured is the information necessary to select and apply various feeding and transfer mechanisms in the automation of assembly. Component and product design to make automatic assembly feasible are also discussed. The performance and economics of assembly machine systems are analysed. Programmable assembly machines and robots are evaluated and comparisons made of the different assembly machine types.

A simplification of the economic analysis made of savings would be more practical and some mention of discounted cash flow techniques in this con- text would have been of value. More information should have been included on the use of micropressors as a means of machine control and of their ad- vantages in increasing machine reliability and flexibility and their ability to print-out information of value to management, such as the downtime (with causes) for each workhead. In the design of assembly machines a discussion on the sub-contracting of design work -- such as orientating devices in bowl feeders versus "in-house design" -- would have been of interest. Also, infor- mation on the pitfalls of estimating "debugging" and development time and allowing adequately for this should have been made.

Along with the Product Data Memoranda series from the Institution of Production Engineers, "Automat ic Assembly" offers an excellent s tudy of the field of assembly automation and is a necessary and worthwhile pur- chase for people involved in this field.