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analysts and designers of machinery and structures concerned with fatigue or impact. The designer is provided with stress concentrat ion factors and methods for their application. Since all charts are in dimensionless form, the text will also be of value to designers with a limited knowledge of English.

Inspection of the outline in the Contents reveals a system of classification by load type (tension, bending, torsion) and stress concentrat ion geometry. This system of classification will be an aid to most users. In addition, for ease in locating a chart, important pages are marked with a narrow grey screen on the right-hand margin.

In Chapter One, the author discusses: (1) stress concentrat ion and the stress concentrat ion factor, (2) failure theories--normal stress criterion, Mohr theory, maximum shear theory, and Mises criterion, (3) notch sensitivity and (4) design relations for steady, alternating, and combined stresses. Chapter Two is concerned with stress concentrat ions for notches and grooves of various geometries under tension, bending, and torsion. In this chapter, over 44 figures are given and each is discussed with respect to how the stress concentrat ion values were obtained and by whom. Chapter Three deals with stress concentrat ion factors for shoulder fillets. Figures are again preceded by a discussion and are classified according to stress state and fillet shape. Chapter Four establishes stress concentrat ion factors for holes and Chapter Five, the final chapter, deals with stress concentrat ion factors for miscellaneous machine elements: keyseats, splined shafts, gear teeth, press filtted members, bolts and nuts, curved bars, helical springs etc.

This work contains approximately 212 figures and refers to over 381 sources. It will be of value both as a handbook and as a reference text.

K U R T M. M A R S H E K Mechanical Engineering Department,

University of Connecticut, Storrs, Connecticut 06268, U.S.A.

D. J. Leech: Management of Engineering Design. John Wiley & Sons, New York (1972). 258 pp.

THIS book on engineering design deals with design strategy from a value engineering viewpoint. The author informs designers in industry, and students in engineering design of the need for formal problem definition and introduces them to the design specification. He also discusses, in detail, methods for finding answers satisfying specifications, problems associated with producing a final product, and techniques useful in design management.

Intended for use in an undergraduate course, this twenty-chapter, five part text will serve as an introduction to the strategy, organization and communication involved in the design process. In Part l, Defining the Problem, the situation existing between designer and customer, and the relationship of product and profit are covered. Also examined are the topics: the system being designed, starting the design, design objectives, resources, environment, and the design specification.

Part 2 concerns the problem of finding feasible solutions once design specifications are written. It begins with a discussion of the ramifications of design in the context of a "normal commercial world" and follows with methods for creating possible solutions

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and then selecting the best from those available. In Part 3, Making the Hardware, the author reveals the structure and communications within a design team. Part 4, The Management of Design, includes chapters on critical path methods, availability of resources, and accounting. Part 5, Models and Tools of Analysis, has chapters entitled, "Failure, Reliability and Life" , "Models and Optimization", "Optimization and Design", "Linear Programming", and "The Man/Machine Interface". Included at the end of each part are topics for discussion and several useful exercises. At the end of the text is an appendix dealing with value engineering.

Notewor thy are the interesting introductions for each part. A brief discussion of pertinent references as well as the author 's purpose, objectives, and phi losophy--both design and educat ional--are presented. Most readers will share similar views and opinions.

For the engineering school interested in giving their students an introduction to engineering design management and also providing them with managerial tools for modeling and analysis, this book is highly recommended.

K U RT M. M A R S H E K Mechanical Engineering Department,

University of Connecticut, Storrs, Connecticut 06268, U.S.A.

A. D. S. Carter: Mechanical Reliability, The Macmillan Press Ltd, London, (published in U.S.A. and Canada by Halsted Press, Division of John Wiley & Sons, Inc., New York), 1972, 146 pp.

THIS IS an interesting little book that provides adroit handling of much commonly unassembled information. Quoting from the introduction, " . . . the subject has been t r e a t e d . . , with the general mechanical engineer in mind--not the specialist." This objective has been carried out throughout most of the book. Occasionally it is unfortunate for a little more detail could have been very helpful.

The text loses its practical nature in some places by improper (or lack of) definition. For example, quoting from p. 20: "With perfectly smooth loading represented by a unique load the failure rate after the initial application of the load is zero no matter how bad the design." This is a paradoxical statement implying an arbitrary definition of good design that could rightfully be overdesign and economically undesirable. The conventional proof of good design is f reedom from failure under the planned conditions of use.

Not all of the sections are covered in comparable detail. For example, Section 2.2.5 entitled "Complete Life Failure Pat tern" mentions in the first paragraph that there are different additive cases and then refers briefly to Hastings method for calculating the transient failure pattern from the first generation failure patterns. On new devices, both these subject areas can be very important. It would have been helpful if these subjects had been explained in the same detail that was used in earlier sections. With this helpful expansion, much of the material in Section 2.2.5 could constitute a new section perhaps entitled "Life Characteristics of Complex Maintained Equipment ." This should come after the closing material in Section 2.2.5 that completes the bathtub discussion.

Misleading titles and statements in some areas require a specialist to interpret. An example is the statement on p. 26 that: "The purely random phenomena of Section