Table of contents

Volume 7

Number 6, June 1996

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RAPID COMMUNICATION

L863

An electrical capacitance tomography (ECT) sensor consists of multiple electrodes, usually mounted outside an insulating pipe. To calibrate an ECT system it has been necessary to physically fill the sensor consecutively with samples of a low permittivity material and a high permittivity material to be imaged. In some cases, however, it is physically difficult to fill the sensor with a material with a suitable permittivity. This paper describes a calibration method in which the sensor does not have to be filled with the material to be imaged, thus allowing materials of any permittivities in a certain range to be imaged. Experimental results show that the full-range capacitance values predicted by this method are satisfactory, with a root mean square (RMS) error of 7.1%.

PAPERS

869

and

A procedure is derived by which sensory attributes can be scaled as a function of various physical and/or chemical properties of the object to be tested. This procedure consists of four successive steps: (i) design and experiment, (ii) fabrication of specimens according to the design parameters, (iii) assessment of a sensory attribute using sensory evaluation and (iv) derivation of the relationship between the parameters and the sensory attribute. In these steps an experimental design using orthogonal arrays, analysis of variance and regression analyses are used strategically. When a specimen with the design parameters cannot be physically fabricated, an alternative specimen having parameters closest to the design is selected from a group of specimens which can be physically made. The influence of the deviation of actual parameters from the desired ones is also discussed. A method of confirming the validity of the regression equation is also investigated. The procedure is applied to scale the sensory sharpness of kitchen knives as a function of the edge angle and the roughness of the cutting edge.

876

, , and

The basics of insulators' pollution processes are first reviewed, including the main physical and chemical factors involved. A novel fibre-optic-based device for measuring leakage and burst current is described, including the mechanical mounting, electronic modules and the corresponding hardware and calibration software of the equipment developed. A comparative analysis of the advantages and disadvantages of the design with similar equipment is presented. Finally, experimental results in a fog chamber are presented. Some statistical analyses, that can be useful in understanding the pollution process in electrical insulators, will be proposed.

882

A local-field-effect correction scheme, using a neural-network-based approach, is proposed for quantitative voltage contrast measurements (QVCM) in the scanning electron microscope (SEM). This technique showed some (though modest) improvement over an iterative correction scheme proposed previously. The correction technique also gives reasonably accurate voltage measurements on a multi-electrode test structure, even under low-extraction-field conditions for which local field effects are especially serious. The neural network employed is a back-propagation network with an adaptive learning rate to decrease the training time of the correction scheme. A momentum constant is also added to the back-propagation learning rule to minimize the chances of the network becoming stuck in a local minima of the error surface curve. The addition of momentum has a low-pass filtering effect on noise in the training data set and this could possibly account for the modest improvement in performance of this approach over the earlier iterative approach.

888

A fibre-optic probe has been developed for measuring the gas temperature in flames. The principal feature of the method is that the probability distribution function of the gas temperature can be obtained locally in a particle-loaded gas flow. Instant gas temperatures are determined from infrared emission spectra obtained from the interior of a 1.3 MW pulverized coal flame. Thermal radiation from different positions in the furnace is collected with the infrared fibre-optic probe and the emission spectra are measured with a Fourier transform infrared spectrometer. The experiments show that the instant local gas temperature can be extracted from the brightness temperature spectrum at the fundamental band of , at which self-absorption is minimized. The brightness temperature spectrum is very useful for evaluation of the measurement, in that the measuring conditions for applying the method are fulfilled. Good agreement is observed between the temperatures measured with the infrared probe and those measured with a suction pyrometer. The performance and characteristics of the infrared relative to the suction pyrometer method as well as laser methods in flames are compared and discussed. The gas temperature profile and probability distribution functions can be obtained even faster with the infrared probe than can the mean gas temperature with a conventional suction pyrometer.

897

, , , , and

A new full Earth's field dynamic feedback fluxgate magnetometer is described. It is based entirely on digital signal processing and digital feedback control, thereby replacing the classical second harmonic tuned analogue electronics by processor algorithms. Discrete mathematical cross-correlation routines and substantial oversampling reduce the noise to 71 pT root-mean-square in a 0.25 - 10 Hz bandwidth for a full Earth's field range instrument.

904

, and

A simple apparatus for sub-surface electron paramagnetic resonance (EPR) imaging of a cut sample is described. A two-dimensional EPR image corresponding to the electron spin-density distribution of the DPPH test sample has been obtained by using a marginally oscillating self-detecting microwave frequency EPR spectrometer. Higher spatial resolution is obtained by using a deconvolution algorithm and the image processing technique of inverse filtering.

908

, , and

We have studied and tested a digital telephone line compatible with ISDN via optical fibre. We examined the transmission of interface S relative to network termination (NT). The main part of this work concerns an optical fibre microphone that modulates the light signal directly by acoustic vibrations, without any electric intermediate.

911

and

A laser system for displacement measurements, based on the iodine-stabilized He - Ne laser wavelength standard at 633 nm, has been built up. Two resonator mirror moving systems with displacement ranges of 3 and respectively were investigated and the guidance deviations of the latter were corrected. An inductive displacement transducer was calibrated using the measuring laser. The overall measurement uncertainty was estimated for the calibration of the inductive transducer for a displacement length of .

918

, and

An electronic speckle shearing interferometer, or TV shearometer, characterized by a very small shear, has been used to measure the exact vibration amplitude derivative of a vibrating object. The technique is based on a heterodyne speckle shearing interferometer and uses fringe analysis methods appropriate when less than one fringe is observed on the vibrating object.

922

, , and

The paper presents a general mathematical procedure for the calculation of the measuring location of three pairs of laser beams and of the shape of the created measuring volumes after refraction at curved surfaces. The relative displacement in space of the beams and the corresponding velocity component inclinations are also calculated. The beam equations are solved, without any small-angle approximations, for an arrangement corresponding to a 3D laser Doppler anemometer. The proposed method has been validated by comparison with experimental results. The correction procedure has been applied to a typical configuration of a turbomachinery passage and representative beam displacement calculations are presented. Possibilities offered by the method in designing experiments as well as correcting obtained results are discussed.

932

, and

The recently developed dual-probe heat-pulse technology permits the rapid, automatic monitoring of soil volumetric heat capacity, thermal diffusivity, and conductivity. The method relies on parameter fits of equations describing received pulse shape. These, in turn, depend on the particular geometric model assumed to characterize the sensor system. This paper describes an estimation procedure applicable to a wide class of sensor geometries. Key attributes of the method are that: (1) it replaces multidimensional, parameter space searches with a single, univariate optimization; (2) no derivatives are required for point estimates; (3) except for a one-time-only table precalculation, computational requirements are independent of model complexity; and (4) it computes its own initial estimates from the data. A computer implementation of the method is presented along with fits of finite and infinite line source emitters to temperature data from laboratory dual-probe heat-pulse experiments. The results show the new method gives answers identical to the commonly used Marquardt algorithm.

939

, and

A novel interferometric method for determining mechanical stress in vacuum-deposited thin metallic layers on glass substrates is described. Stress in the glass - metal structure affects the curvature and hence the resonant frequencies of the substrate. Thus, by measuring variations of the resonant frequencies, the curvature and hence the stress can be determined. The technique of photo-thermoelastic bending has been adapted to this measurement. Measuring the variation in resonant frequency is a very sensitive method of determining the substrate curvature. Tests of the new technique using thin Cr films on glass demonstrate its effectiveness.

944

, and

A new broad-beam ion source of alkali ions for use in ultra high vacuum was designed, built and tested. The basic principles used have advantages over gas-fed broad-beam ion sources, because there is no need for differential pumping, and because an intrinsically pure ion beam obviates the necessity for charge-to-mass analysis. The source is based on the effect of thermionic emission of ions from solid potassium aluminosilicate emitter. An ion beam current of 0.4 mA has been achieved at an extraction voltage of 3.5 kV with 1.5 cm beam diameter. The degassed broad-beam ion source in operation does not appreciably influence the background pressure in the ultra high vacuum system.

949

, and

An automated system is described which facilitates fast high-resolution measurements of Q, coupling and resonant frequency of modes in a microwave resonator. We demonstrate measurements of Q and coupling with a resolution of and a fractional frequency measurement resolution of . The system is used to measure the temperature-dependence of the mode Q, coupling and resonant frequency for modes in two high-Q cryogenic sapphire resonators. Measurement of the temperature variation of Q is used to estimate the geometric factor, which is a measure of the mode energy confinement to the sapphire element distribution. Measurement of the mode frequency temperature-dependence can be used to determine the effect of paramagnetic impurities in the sapphire.

954

, , and

A portable mechanical tester is described which is both lightweight and cheap to produce. The machine is simple and convenient to operate and requires only a minimum of personnel training. It can be used to measure the fundamental mechanical properties of pliant solids, particularly toughness (in the sense of `work of fracture') using either scissors or wedge tests. This is achieved through a novel hardware integration technique. The circuits are described. The use of the machine does not require a chart recorder but it can be linked to a personal computer, either to show force - displacement relationships or for data storage. The design allows the use of any relatively `soft' mechanical test, i.e. tests in which the deformability of the frame of the machine and its load cell do not introduce significant errors into the results. Examples of its use in measuring the toughness of biomaterials by scissors (paper, wood) and wedges (mung bean starch gels) are given.

DESIGN NOTES

963

It is demonstrated that measurements of power levels expressed in units of decibels are prone to noise-induced bias as a result of the logarithmic nature of the decibel scale. Estimates of the effect of the bias on the mean of a repeated set of values and on the mode value are given, indicating that allowance for noise-induced bias is important in the reporting of measurements made with low values of signal-to-noise ratio of the order < 10.

965

, and

A closed-cycle helium refrigerator is utilized for the development of a facility for performing Mössbauer and electrical resistivity studies at low temperatures down to 18 K. This facility includes a vibration isolation assembly in order to isolate the sample holder from the vibrations arising from the cold head of the closed-cycle refrigerator. A top-loading chamber and a set of bellows are used for this purpose. The performance of the system was tested by recording the spectra of natural iron foil at 300 K when the closed-cycle refrigerator was on and when it was off. The typical width of the outer lines of the Fe spectra obtained was , which indicates the effective isolation of vibration. A facility for electrical resistivity measurements by a four-probe method was also developed for use in the same facility for Mössbauer studies.

969

and

To evaluate temperature-dependent stretching experiments of biological cells down to sub-zero temperatures in a high-frequency electric field, knowledge of the electrical parameters of the suspension is necessary. A measuring system was developed to determine the relative permittivity and the ionic conductivity of supercooled aqueous solutions and suspensions in the frequency range 0.1 - 2 MHz. A parallel-plate capacitor was used in connection with an impedance analyser and a cryostat. The errors caused by the cables needed between analyser and cooled capacitor were minimized. Field homogenization within the measuring space is realized by correcting the reference potential at the guard ring. The starting capacitance at each temperature was reproduced by testing the value after re-assembling the capacitor. Damaging of the capacitor by ice formation is prevented. For testing, a comparison was made with literature data and first measurements of supercooled aqueous solutions.

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020

Measurement Science and Technology Diary of events Published under licence by IOP Publishing Ltd Measurement Science and Technology, Volume 7, Number 6 Citation 1996 Meas. Sci. Technol. 7 020 41 Total downloads Turn on MathJax Get permission to re-use this article Share this article Share this content via email Share on Facebook (opens new window) Share on Twitter (opens new window) Share on Mendeley (opens new window) Article information Abstract Entries marked by * appear here for the first time. 1996 June * 10--12 Introduction to Opto-mechanical Design, Bromley, Kent Details: Sira Technology Center Training Registration, South Hill, Chislehurst, Kent BR7 5EH, UK. E-mail: courses@sira.co.uk, WWW: http://www.sira.co.uk 10--14 European Symp. on Lasers, Optics and Vision for Productivity in Manufacturing I, Besanon, France Details: SPIE, PO Box 10, Bellingham, WA 98227-0010, USA 10--14 2nd European Symp. and Exhib. on Optical Instrument and Systems Design, London, UK Details: EOS Secretariat, BP 147, 91403 Orsay Cedex, France * 13 Advanced Topics in Opto-Mechanics, Bromley, Kent Details: Sira Technology Center Training Registration, South Hill, Chislehurst, Kent BR7 5EH, UK. E-mail: courses@sira.co.uk, WWW: http://www.sira.co.uk 18--21 3rd OPTATEC, Frankfurt am Main, Germany Details: Ms Bettina Knauer, Public Relations and Advertising, Schall Trade Fairs, D-72633 Frickenhausen, Germany 24--27 2nd Airborne Remote Sensing Conference, San Francisco, USA Details: Wendy Raeder, ERIM, PO Box 134001, Ann Arbor, MI 48113-4001, USA * 26--28 Actuators 96, Bremen, Germany Details: Axon Technologie Consult GmbH, Conference Office, Hanseatenhof 8, D-28195 Bremen, Germany * 27 Digital Image Acquisition, Bromley, Kent Details: Sira Technology Center Training Registration, South Hill, Chislehurst, Kent BR7 5EH, UK. E-mail: courses@sira.co.uk, WWW: http://www.sira.co.uk July 2--4 Int. Microscopy and Image Analysis Conf. and Exhib., London, UK Details: Allison Winton, Royal Microscopical Society, 37/38 St Clements, Oxford OX4 1AJ, UK * 4 Laser Safety in Industry and the Laboratory, London, UK Details: Sira Technology Center Training Registration, South Hill, Chislehurst, Kent BR7 5EH, UK. E-mail: courses@sira.co.uk, http://www.sira.co.uk * 10 Advances in Instrumentation for Magnetic Measurements, Cardiff, UK Details: Margaret Swadling, UK Magnetics Society, Berkshire Business Centre, Post Office Lane, Wantage, Oxon OX12 8SH. E-mail: 100520.655@compuserve.com 8--11 8th Int. Symp. on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal Details: Professor M V Heitor, Insstituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1096 Lisboa Codex, Portugal * 15--16 Sensors and Actuators, Manchester, UK Details: Teresa Davies, Conference Department, The Institute of Materials, 1 Carlton House Terrace, London SW1Y 5DB 15--19 Int. Conf. on Quantitative Surface Analysis, Guildford, Surrey, UK Details: QSA-9 Conference Secretariat, Department of Materials Science and Engineering, University of Surrey, Guildford, Surrey, GU2 5XH, UK 17--18 Unsteady Aerodynamics, London, UK Details: The Royal Aeronautical Society, 4 Hamilton Place, London W1, UK 21--26 XVIIth Int. Symp. on Discharges and Electrical Insultation in Vacuum, Berkeley, CA, USA Details: Simone Anders and André Anders, XVIIth ISDEIV Chairs, Lawrence Berkeley Laboratory, MS 53, University of California, Berkeley, CA 94720, USA 22--24 1st. European Magnetic Sensors and Actuators Conf. (EMSA'96), Iasi, Romania Details: Dr H Chiriac, Institute of Technical Physics, 47 Mangeron Blvd., 6600 Iasi 3, Romania 29--1 August Int. Conf. on Applications of Photonic Technology, Montreal, Canada Details: Optical Society of America, Conference Sservices Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA August 4--9 Int. Symp. on Optical Science, Engineering and Instrumentation, Denver, Colorado, USA Details: SPIE, PO Box 10, Bellingham, WA 98227-0010 USA 19--23 17th Congr. of the Int. Commission for Optics, Taejon, Korea Details: Professor B Y Kim, Department of Physics, KAIST, 373-1 Kusong-dong, Yusong-gu, Taejon 305-701, Korea 25--30 13th Int. Conf. on Pattern Recognition, Vienna, Austria Details: c/o Austropa Interconvention, A-1043 Vienna, POB 30, Austria September * 2--3 IAPR Workshops on Remote Sensing and Applications in Industry, Graz, Austria Details: Axel Pinz, Technical University Graz, Institute for Computer Graphics, Muenzgrabenstrasse 11, A-8010 Graz, Austria. E-mail: pinz@icg.tu-graz.ac.at * 9--12 Seventh British Machine Vision Conference, Edinburgh, UK Details: Judith Gordon, Department of Artificial Intelligence, University of Edinburgh, 5 Forrest Hill, Edinburgh EH1 2QL, UK. E-mail: BMVC96@aifh.ed.ac.uk 8--13 CLEO/Europe '96, Hamburg, Germany Details: Meetings and Conferences Department, Institute of Physics, 47 Belgrave Square, London SW1X 8QX, UK 10--13 VIII European Signal Processing Conf., Trieste, Italy Details: The Office, v.S Nicolo 14, 34121 Trieste, Italy 16--19 Int. Conf. on Image Processing, Lausanne, Switzerland Details: Professor Henri Maitre, ICIP-96/Dept IMA, Ecole Nationale Superieure des Telecommunications, 46 Rue Barrault, 75 634 Paris Cedex 13, France 23--26 3rd IEEE Int. Conf. on Dielectric Materials, Measurements and Applications, Bath, UK Details: Louise Hudson, Conference Services, IEE, Savoy Place, London WC2R 0BL, UK * 23--27 European Symp. on Satellite Remote Sensing III, Taormina, Italy Details: EUROPTO c/o Direct Communications GmbH, Xantener Straß e 22, D-10707 Berlin, Germany. E-mail: 100140.3216@compuserve.com 24--27 Boundary Element Conf., Braga, Portugal Details: Sue Owen, Wessex Institute of Technology, Ashurst Lodge, Ashurst, Southampton SO40 7AA, UK 25--28 Advanced Mathematical Tools in Metrology III, Berlin, Germany Details: Physikalisch-Technische Bundesanstalt, Euro-Conference 96, Abbestrasse 2-12, D-10587 Berlin October * 1--3 Symp. on Optical Fiber Measurements, Boulder, CO, USA Details: Gordon Day, National Institute of Standards and Technology (815.00), 325 Broadway, Boulder, CO 80303, USA * 7--10 ICSPAT `96, 7th Int. Conf. on Signal Processing Applications and Technology, Boston, MA, USA Details: Megan Forrester, Miller Freeman, 600 Harrison Street, San Fransisco, CA 94107. E-mail: dsp@mfi.com 7--11 2nd European Symp. and Exhib. on Imaging Sciences and Information Services, Berlin, Germany Details: EOS Secretariat, BP 147, 91403 Orsay Cedex, France * 7--11 European Symp. on Advanced Imaging and Network Technologies, Berlin, Germany Details: EUROPTO, c/o Direct Communications GmbH, Xantener Straß e 22, D-10707 Berlin, Germany 9--11 3rd European Conf. and Exhibition on High Voltage Measurements and Calibration, Milan, Italy Details: Janine Stook, Senior Conference Organiser, ERA Technology Ltd, Cleeve Road, Leatherhead, Surrey KT22 7SA, UK 13--16 3rd Int. Conf. on Electronics, Circuits and Systems, Rodos, Greece Details: ICECS Secretariat, EE Department, University of Patras, 26500, Greece 14--18 American Vacuum Society 43rd Nat. Symp., Philadelphia, PA, USA Details: Angela Mulligan, AVS, 120 Wall Street, 32nd Floor, New York, NY 10005, USA 20--25 Interdisciplinary Laser Science Conf., Rochester, NY, USA Details: Optical Society of America, Conference Services Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA * 29--31 7th Conf. on Signal Processing Applications and Technology, Santa Clara, CA, USA Details: DSP Associates, 49 River Street, Waltham, MA 02154, USA. E-mail: icspat@dspnet.com November 11--15 5th Int. Conf. on Nuclear Microscopy Technologies and Applications, Santa Fe, NM, USA Details: Dr B L Doyle, Dept 1111, MS 1056, Sandia National Laboratories, Albuquerque, NM 87185-1056, USA 20--22 2nd Int. Symp. on Micro Total Analysis Systems, Basel, Switzerland Details: µTAS'96, c/o Mrs E Müller, K-127.1.54, Ciba Geigy Inc., CH-4002-Basel, Switzerland December * 2--6 Lasers '96, Portland, OR, USA Details: LASERS '96, P.O. Box 245, McLean, VA 22101, USA 1997 February 16--21 Optical Fiber Communication Conf., Dallas, TX, USA Details: Optical Society of America, Conference Services Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA May 18--23 Conf. on Lasers and Electro-Optics, Baltimore, MD, USA Details: Optical Society of America, Conference Services Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA 18--23 Quantum Electronics and Laser Science Conf., Baltimore, MD, USA Details: Optical Society of America, Conference Services Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA 19--23 ICRM'97, Gaithersburg, MD, USA Details: Dr J M R Hutchinson, Radioactivity Group, NIST, Gaithersburg, MD 20899, USA June * 9--11 10th Scandinavian Conference on Image Analysis (IAPR), Lappeenranta, Finland SCIA `97, Department of Information Technology, Lappeenranta University of Technology, P.O. Box 20, FIN-53851, Lappeenranta, Finland. E-mail: SCIA97@lut.fi, WWW: http://www.lut.fi/scia97 September 1--4 5th Triennial Int. Symp. on Fluid Control, Measurement and Visualization, Hayama, Japan Details: FLUCOME Desk, Kintetsu International, 7th Floor Takakyu Building, 19 Kanda Matsunaga-cho, Chiyoda-ku, Tokyo 101, Japan 8--12 World Tribology Congr., London, UK Details: Conference Services Department (C491), Institution of Mechanical Engineers, 1 Birdcage Walk, London SW1H 9JJ, UK 15--18 2nd Int. Coll. Micro-Tribology `97, Poland Details: Zygmunt Rymuza, Warsaw University of Technology, Institute for Design of Precise and Optical Instruments, Chodkiewicza 8/623, 02-525 Warszawa, Poland October 11--17 OSA'97 Annual Mtg, Long Beach, CA, USA Details: Optical Society of America, Conference Services Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA 11--17 Interdisciplinary Laser Science Conf., Long Beach, CA, USA Details: Optical Society of America, Conference Services Department, 2010 Massachusetts Ave., NW, Washington DC 20036-1023, USA 1998 March * 31--2 April Second Scientific Instrument Association Conference and Exhibition, London, UK Details: SiA, PO Box 192, Watford, Herts WD1 8GF. WWW: http://www/interlab.co.uk/interlab

BOOK REVIEWS

021

Rather than concentrating on a specific section of sensor technology, this book attempts (and to some extent succeeds) in providing what can only be described as an in-depth overview of the whole field of intelligent sensing. Virtually all of the mathematical analysis normally associated with this subject area is discarded in favour of a practical implementation approach. Explicit diagrams and, in many cases, photographs of the actual sensor element structures are included together with schematics of the relevant signal processing circuits.

A large proportion of the book deals directly with micro-machining and most of the commonly used fabrication processes are described step by step. Integration with on-chip microprocessors, analogue to digital converters and other signal conditioning circuitry are illustrated in detail, with comparisons between the different intelligent systems made in terms of `sensor IQ'. Aspects of control engineering, ranging from simple PID to neural networks and artificial intelligence techniques are also mentioned in the context of intelligent sensing, without getting into too much detail where sensor fusion and data processing are concerned.

Throughout the book, current and proposed industrial standards are referred to and in some instances their meanings and relevance to smart sensing and communications is explained. Given the recent proliferation of field bus, automotive telemetry and device packaging standards, such up to date information is most welcome, though possibly at the risk of obviating much of the book within the next few years.

The only serious omission lies in the field of optical devices where nothing appears in terms of fibre optic sensors. This is a little disappointing given that modern micro-machining technology and the above mentioned communications systems have opened the way for much more of this type of technology in the past few years.

Despite this being a general text, large lists of references appear at the end of each chapter. Unfortunately, these pertain mainly to symposia, workshop and conference proceedings rather than more detailed text books essential to anyone wishing to futher their knowledge in any particular aspect of sensing. Excessive reference to Motorola application reports and other commercial data also detracts from the book's usefulness. A helpful acronym glossary is provided, though not every acronym used by the author appears in it.

The book will be of most use to technicians, though benefit may be gained by engineers, physicists and managers seeking a general introductory text to the field of smart sensors. The analytic content is not deep enough for most university curricula, however it may serve well as an auxilliary text in undergraduate studies.

022

This book provides an excellent introduction to the topic of smart structures and materials. It is easy to read, being only 200 pages long. It begins with a layman's view of the topic, placing smart structures in terms of simple concepts before moving on to a step by step approach to the specifics. The style of the book is meant to be at the awareness level more than the detailed analysis level and the author achieves this successfully. The use of comparative tables in almost every chapter is particularly good for quickly disseminating information. All the important topics are covered, albeit somewhat briefly in some sections. The eight chapters span aspects such as materials, sensing and actuation and signal processing. Several case studies are included and the book concludes by contemplating where the future may be with regard to smart structures and materials. The most detailed chapter of the book deals with the author's principal research field, namely sensing technologies and optical fibres. It is somewhat unfortunate that this is the only chapter which offers a good list of references; this is the only real weakness of the book.

Overall, this is a worthwhile purchase for undergraduates, researchers and industrialists who want to be exposed to the important developing area of smart materials and structures and who want an easy text to read on the subject. The author has done a splendid job of producing a book that should stimulate further interest in a technology which is clearly part of the future.