THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

This article presents an overview of the developments in stainless steels made since the 1990s. Some of the new applications that involve the use of stainless steel are also introduced. A brief introduction to the various classes of stainless steels, their precipitate phases and the status quo of their production around the globe is given first. The advances in a variety of subject areas that have been made recently will then be presented. These recent advances include (1) new findings on the various precipitate phases (the new J phase, new orientation relationships, new phase diagram for the Fe–Cr system, etc.); (2) new suggestions for the prevention/mitigation of the different problems and new methods for their detection/measurement and (3) new techniques for surface/bulk property enhancement (such as laser shot peening, grain boundary engineering and grain refinement). Recent developments in topics like phase prediction, stacking fault energy, superplasticity, metadynamic recrystallisation and the calculation of mechanical properties are introduced, too. In the end of this article, several new applications that involve the use of stainless steels are presented. Some of these are the use of austenitic stainless steels for signature authentication (magnetic recording), the utilisation of the cryogenic magnetic transition of the sigma phase for hot spot detection (the Sigmaplugs), the new Pt-enhanced radiopaque stainless steel (PERSS) coronary stents and stainless steel stents that may be used for magnetic drug targeting. Besides recent developments in conventional stainless steels, those in the high-nitrogen, low-Ni (or Ni-free) varieties are also introduced. These recent developments include new methods for attaining very high nitrogen contents, new guidelines for alloy design, the merits/demerits associated with high nitrogen contents, etc.

Recent developments in stainless steels

Cellulosic/synthetic fibre reinforced polymer hybrid composites: A review

The Foundations of Statistics By Prof. Leonard J. Savage. (Wiley Publications in Statistics.) Pp. xv + 294. (New York; John Wiley and Sons, Inc.; London: Chapman and Hall, Ltd., 1954.) 48s. net.

Probability and Statistical Inference

Poisson's ratio values for rocks

Contact-resonance atomic force microscopy (CR-AFM) has been used to measure the viscoelastic loss tangent of soft materials such as polymers. Usually, the damping is attributed to the dissipation in the contact volume due to internal friction and air damping of the cantilever. However, partial slip or even full sliding can exist in the contact zone under tangential loading, and thus, the accompanying energy dissipation must be taken into account when measuring the damping constant Q l o c − 1. Here, the stick-to-sliding transition of the tip-sample contact in CR-AFM was studied. Amplitude drops were observed in the resonance curves caused by such stick-to-sliding transitions. The results show that the stick-to-sliding transition arises under small contact forces and large excitation amplitudes. Extra energy loss from full sliding induces large contact damping. The critical lateral displacement needed for the stick-to-sliding transition varies linearly with the contact radius.

Stick-to-sliding transition in contact-resonance atomic force microscopy

Periodic assessment of steam generator tubes of a sodium-cooled nuclear reactor is very crucial for smooth operation of steam generators. To examine the integrity, an in-bore magnetostrictive trans...

Influence of thermal expansion bend and tubesheet geometry on guided wave inspection of steam generator tubes of a fast breeder reactor

Influence of thermal ageing and creep on ultrasonic velocity in 9Cr-1Mo ferritic steel

Non-destructive examination of steam generator (SG) tubes of Fast Breeder Reactors is of paramount importance. The inspection needs to be carried out from the inner side of an SG tube due to the constraint in accessibility. Recently, the magnetostrictive ultrasonic guided wave (MUGW) technique has been proposed as an alternative for the inspection of SG tubes. As a commercial MUGW probe for small-diameter ferromagnetic tubes is not available, it needs to be designed and developed with optimum parameters. This paper proposes a three-step optimization approach for the development of a MUGW probe, namely optimization of the diameter and length of a permanent magnet (for bias) finite element modeling based, optimization of the width of the transmitter and receiver coils of the probe by empirical modeling and the optimization of the number of turns of the transmitter and receiver coils by equivalent circuit models. A MUGW probe is fabricated and tested experimentally to validate the optimized parameters. Experiments show the validity of the approach in terms of generation, long-range propagation (47.6 m) of L(0,2) mode at 300 kHz, and the required sensitivity (multiple 10% wall thickness deep uniform wall loss circumferential grooves) in SG tubes.

Optimization of Geometrical Parameters of a Magnetostrictive Ultrasonic Guided Wave Probe for Tube Inspection

An ultrasonic spectral analysis based methodology has been developed and successfully implemented to measure wall thickness in the range of 0.3 to 0.7 mm in iron thimbles using low frequency ultrasonic waves (around 10 MHz). Conventional ultrasonic techniques cannot be used in such cases because of the low thickness of the thimble and the presence of curvature. Using a low frequency (15 MHz) immersion transducer and low digitization (under 200 MHz), an accuracy of ±10 μm has been achieved. The importance of the window for selection of time domain data for spectral analysis has been clearly brought out. A software program has been developed for automated thickness measurement across a line scan and for displaying the surface plot of thickness variations using the developed methodology.

Anish Kumar

Papers

Stick-to-sliding transition in contact-resonance atomic force microscopy

Influence of thermal expansion bend and tubesheet geometry on guided wave inspection of steam generator tubes of a fast breeder reactor

Influence of thermal ageing and creep on ultrasonic velocity in 9Cr-1Mo ferritic steel

Optimization of Geometrical Parameters of a Magnetostrictive Ultrasonic Guided Wave Probe for Tube Inspection

Ultrasonic Spectral Analysis Methodology for Thickness Mapping of Electrochemical Hydrogen Meter Thimbles