INTERNATIONAL SOUND AND VIBRATION DIGEST Volume 1, Number 1 Date: September 19, 1994 Editor-in-Chief: Malcolm J. Crocker, Auburn University, USA Assistant Editor: Yana Sokolova, Auburn University, USA Editorial Board: Duan-shi Chen, Jiao Tong University, Shanghai, CHINA Jean L. Guyader, INSA de Lyon, FRANCE Colin H. Hansen, University of Adelaide, AUSTRALIA Hanno Heller, DLR, Braunschweig, GERMANY Nikolay Ivanov, Baltic State University, St. Petersburg, RUSSIA Finn Jacobsen, Danish Technical University, DENMARK G. Krishnappa, Institute for Machinery Research, NRC, CANADA Conny Larsson, Uppsala University, SWEDEN Martin V. Lowson, University of Bristol, UK Leonid M. Lyamshev, Andreev Acoustics Institute, Moscow, RUSSIA M.L. Munjal, Indian Institute of Science, Bangalore, INDIA David E. Newland, The University of Cambridge, UK Michael P. Norton, University of Western Australia, AUSTRALIA A. Selamet, The University of Michigan, Ann Arbor, USA Andrew F. Seybert, University of Kentucky, Lexington, USA Jan W. Verheij, TNO, Delft, THE NETHERLANDS. Current number of subscribers: 1144 To send a submission to the IS&V DIGEST or to subscribe or unsubscribe send information by E-mail to yanas@eng.auburn.edu. TODAY'S DIGEST CONTENTS ITEM 1. Publication begins of the INTERNATIONAL SOUND AND VIBRATION DIGEST. ITEM 2. Causal Systems announces low cost EZ-ANC Active noise Control Kit. ITEM 3. New journal, NOISE ABSTRACTS AND REVIEWS begins publication. ITEM 4. First International Noise Exhibition, dB, to be held in Paris. ITEM 5. Third Edition of Random Vibrations, Spectral and Wavelet Analysis by D.E. Newland is published. ITEM 6. Acoustical Surveillance Conference, Paris - Call for Papers. ITEM 7. Book Review: NOISE AND VIBRATION CONTROL ENGINEERING Edited by Leo L. Beranek and Istvan L. Ver. ************************************************************* ITEM 1 Publication of the IS&V Digest Begins ************************************************************* We are pleased to bring you the first issue of the INTERNATIONAL SOUND AND VIBRATION DIGEST. It is planned to publish successive issues electronically every three or four weeks when sufficient technical and news items have been submitted to the editorial office. The intent of the DIGEST is to bring you the latest information on developments in Sound and Vibration as rapidly as possible and to make use of the low cost electronic means of delivery. Initially the DIGEST will be sent free of charge to all professionals interested throughout the world. Later, if it becomes necessary, it may become desirable to request a small administration fee. The DIGEST will publish technical notes, discussions on recent developments, open letters from readers discussing research problems, queries and requests for help, book-reviews, a calendar of events, conference and other announcements on all aspects of sound and vibration. This is your publication. Please submit all items for publication by E-mail to the Editorial office (E-mail address: yanas@eng.auburn.edu). During the start up phase of the DIGEST it was necessary to send several test messages. We apologize for any inconvenience this may have caused you and for the fact that the computer center inadvertently allowed multiple communications between readers at this time. This will not occur again. New readers who wish to receive the DIGEST (i.e. to "subscribe") or readers who wish to discontinue receiving the DIGEST (i.e. to "unsubscribe") should send an appropriate message to: yanas@eng.auburn.edu. On behalf of the Editorial Board of the INTERNATIONAL SOUND AND VIBRATION DIGEST I should like to welcome you as a reader. I hope that you will be an enthusiastic participant in this venture, that you will submit items to the DIGEST so that it will become a lively exchange of the latest technical information making it useful and interesting to our readers. Malcolm J. Crocker **************************************************************** ITEM 2 Low Cost EZ-ANC Active Noise Control Kit Announced **************************************************************** LOW COST ACTIVE NOISE AND VIBRATION CONTROL Colin H. Hansen Department of Mechanical Engineering University of Adelaide South Australia, 5005. chansen@crackle.aelmg.adelaide.edu.au At the University of Adelaide, South Australia the research group working for the past 5 years on active noise and vibration control have formed a company, Causal Systems, with the intention of developing low cost commercial active control systems. Causal Systems is currently working in partnership with Analog Devices to produce an active noise and vibration control development system, called the EZ-ANC. The EZ-ANC is based on the Analog Devices ADSP-2101 processor and includes electronic hardware and software to produce functional active noise and vibration control systems. It can act as the prototype of a controller for the user's target system. As the EZ-ANC kit contains a full description of the technology, the user may design a low-cost active controller, based on the EZ-ANC for inclusion in products such as vehicles, whitegoods, air conditioners and vibration isolation mounts. The EZ-ANC is designed to work in either a feedforward or feedback arrangement and is provided with full software support for feedforward control. Many of the widely used algorithms are already encoded in the EZ-ANC for immediate use. Alternatively, users may easily download new algorithms or their own proprietary algorithms using an IBM-PC (or an ANSI terminal) and the menu- driven user interface communicating to the EZ-ANC via RS232. The modular form of the supplied software makes it a simple task to incorporate customised control algorithms. It is also easy to communicate with the EZ-ANC while it is performing real time control as a separate UART provides the RS232 interface. This makes it possible to track filter weights and error signals in real time. The EZ-ANC kit includes a circuit board which contains an ADSP- 2101 DSP, A/D and D/A converters, and the connectors required to interface the EZ-ANC to a target system. A total of 128k words of external SRAM is provided for the ADSP-2101. The SRAM is available as external program memory, fixed external data memory, and paged external data memory. A socket for a BOOT EPROM is also provided. The default bootstrap program contains the interactive menu system. Custom control software may be programmed into the EPROM to provide a true turn-key system. The analogue inputs of the EZ-ANC can be connected to analogue error sensors such as condenser microphones or accelerometers. There are six inputs and six outputs with 16-bit conversion accuracy. Each analogue input has its own A/D. All 6 A/Ds sample simultaneously, with an input voltage range of q1V. The A/D devices use sigma-delta technology, and include internal anti- aliasing filters. The D/As are synchronised with the A/Ds so that all sampling of signals is performed at the same time. The D/A devices use sigma-delta technology, and so include reconstruction filters at their outputs. The sampling rate of the A/D and D/A hardware is set by a central oscillator module, and may be varied over the range of 5.6kHz to 48kHz. Software is included which enables the effective sampling rate to become an integer fraction of the hardware sample rate. This facility allows use of the EZ-ANC for low-frequency problems, and provides a means of overcoming group delay in the system The EZ-ANC is designed for single-channel and multi-channel control. Up to 5 output channels are supported by the EZ-ANC in feedforward configurations. It is expected that in the near future boards will be cascaded together to provide practically an unlimited number of channels. The following documentation is supplied with the system. A. EZ-ANZ Experimenter's Manual, including active noise control theory. B. EZ-ANC Hardware & Software Reference Manual, including circuit diagrams and documented source code. Initial release of the EZ-ANC is planned for mid-1994. For more information contact Dr. Colin H. Hansen, Dr. Scott D. Snyder or Mr. George Vokalek at the Department of Mechanical Engineering, University of Adelaide, South Australia 5005. Fax: 61-8-3034367. ************************************************************* ITEM 3 New Journal NOISE ABSTRACTS AND REVIEWS Begins Publication ************************************************************* NOISE ABSTRACTS AND REVIEWS Beginning in the summer of 1994 a new journal "Noise Abstracts and Reviews" will be published. The journal is being published in Russia by the Noise and Vibration Control Society in cooperation with the Russian Institute of Scientific and Technical Information (VINITI) supported by the International Scientific Publications, USA, the Editorial Board of the "Larmbekampfung" Journal, Oldenburg, Germany, and the Baltic State Technical University, St. Petersburg, Russia. Issues will each contain a feature article and will survey major scientific research and developments in noise and vibration control and will contain abstracts of at least fifteen hundred to two thousand papers, reports, patents, and books a year, announcements of international meetings, new developments, recent studies, and a calendar of upcoming events providing an invaluable way for readers to keep up with scientific knowledge and developments in the field. Both theoretical and applied noise control topics will be covered. The journal is to be published in English and Russian. The following topics will be covered: general problems of noise and vibration; noise generation at the source; noise of subsonic and supersonic flows; noise reduction in machinery; noise reduction in vehicles; noise at work places; sound propagation, transmission, and reduction; acoustic materials; environmental noise insulation; noise effects on humans; noise and vibration measurements; analytical noise estimation; noise standards, legislation, and regulations. The journal is intended for those working in the field of noise and vibration control for industry, consulting firms, research institutes, universities and research laboratories. Beginning in July, 1994, "Noise Abstracts and Reviews" will comprise six issues per year. There will be three numbers in 1994 and six numbers are planned annually beginning in 1995. The subscription for the first three issues in 1994 is US $60 postpaid for institutions and libraries and US $45 postpaid for individuals. The annual subscription starting in 1995 is US $120 postpaid for institutions and libraries and US $90 postpaid for individuals. _________________________________________________________________ Checks should be made (in US dollars) to International Scientific Publications and drawn on a US bank. NAME_____________________________________________________________ INSTITUTION______________________________________________________ ADDRESS__________________________________________________________ _________________________________________________________________ FAX#_____________________________________________________________ I would like to subscribe to Noise Abstracts and Reviews: Three issues in 1994: individual ($45 US) þ ; institute or library ($60 US) þ Six issues in 1995: individual ($90 US) þ ; institute or library ($120 US) þ I am enclosing a check for US$ _________. _________________________________________________________________ Please return this form to International Scientific Publications, P.O. Box 13, Auburn AL 36831, USA ************************************************************* ITEM 4 First International Noise Exhibition to be held in Paris ************************************************************* First International Exhibition for Protection Against Noise in Buildings and Public Works Paris, FRANCE; November 15 - 18, 1994 dB, the International Exhibition for Protection Against Noise in Buildings and Public Works, will be held for the first time from 15 to 18 November, 1994 at the Parc des Expositions de Paris, Le Bourget, in conjunction with Batimat Industrie and Expoprotection. It is organized by Blenheim Construction. Blenheim Construction's decision to launch it was taken after close consultations with authorities and trade associations. The Sponsoring Committee is comprised of the following organizations: Ministry of Capital Goods Ministry of Housing Ministry of the Environment Ministry of Health Ministry of Industry Ministry of Labour National Noise Council Agency for the Environment and Energy Saving National Building Federation Institute of Architects French Insulation Committee Products, materials and services on show include: -Acoustics/engineering design offices -Inspection offices -Acoustic correction and absorption -Anti-noise screens -Specialist businesses -Sound forecasting software and IT -Equipment noise insulation -Impact noise insulation -Noise and industrial vibration insulation -Public works and site equipment -Measuring equipment -Highways equipment -Protection for individuals -Roadway surfacings -Financial organizations/investors/insurance -Official, professional and technical organizations -Trade press Already over 50 exhibitors have agreed to take part in the trade show dB. The floor area of the exhibition is 4,000 square metres. For more information on the trade show please contact: Mme. Val‚rie Moullec Advertising and Promotions BLENHEIM CONSTRUCTIONS 22-24 rue du Pr‚sident Wilson 92532 Levallous Perret Cedex FRANCE Phone: 33-1-47-56-50-00 FAX: 33-1-47-56-08-18 ************************************************************* ITEM 5 Third Edition of Random Vibrations, Spectral and Wavelet Analysis ************************************************************** Random Vibrations, Spectral and Wavelet Analysis, 3rd Edition, D.E. Newland, John Wiley, ISBN 0-470-22153-4 (in the USA) Longman, ISBN 0-582-21584-6 (outside USA) This is a substantially expanded edition of An Introduction to Random Vibrations and Spectral Analysis and one of the first engineering books to cover wavelet analysis. The wavelet transform is a new method of signal decomposition. It is a major development in vibration analysis and has taken place since the last edition was completed. A signal's mean-square is broken down into its contributions from different frequencies and different times and the results displayed as a contour map. This display has been likened to the way that notes are shown on a musical scale. It allows the changing spectral composition of non-stationary signals to be measured and compared. All the material on random vibrations and spectral analysis, that proved so popular in the first two editions, has been retained; but now it is supplemented by an extensive new chapter on wavelet analysis. Basic theory is thoroughly described and illustrated, with a detailed explanation of how discrete wavelet transforms work. Computer algorithms are explained and supported by examples and a set of problems. A new appendix lists 10 computer programs for calculating and displaying wavelet transforms. Key features: o retains complete introduction to random vibration and spectral analysis theory o one of the first books to explain wavelet analysis to engineers o presents original material on discrete wavelet analysis in an extensive new Chapter 17 o provides a new appendix of wavelet computer programs in the high level language MATLAB (R) o 27 new diagrams and graphs support and clarify the text o simplifies complicated mathematics wherever possible This book is intended to be used as a self-contained text by senior undergraduates in engineering and the applied sciences, and by postgraduates concerned with vibration and signal analysis. It will also be an important source for engineers in industry who will welcome it as a new reference to practical wavelet analysis. David Newland is a Professor of Engineering at Cambridge University. He is a specialist in vibration analysis and has wide experience as a consultant in industry in both the UK and the USA. (R) MATLAB is a registered trademark of The MathWorks, Inc. ACCOMPANYING WAVELET TOOLBOX As previously announced, the book Random Vibrations, Spectral and Wavelet Analysis (John Wiley, New York, ISBN 0-470-22153-4 in the USA and Longman, ISBN 0-582-21584-6 elsewhere) has an accompanying wavelet toolbox in MATLAB*. This toolbox is now available separately from the book with an accompanying descriptive manual. The expanded toolbox currently has 18 M-files for dilation and harmonic wavelet transforms and the presentation of their results in signal analysis. There is also a short demonstration program. Harmonic wavelets have a simple analytical structure, a fast algorithm, are orthogonal, and have many applications in signal analysis. Musical wavelets are developments of harmonic wavelets which allow greater frequency discrimination. The programs compute the one-dimensional dilation wavelet transform and its inverse, display the results of the transform, map the results as contour and mesh diagrams, and compute two-dimensional dilation wavelet transforms and their inverse. There are also programs to compute the harmonic wavelet transform of a one-dimensional sequence, and its inverse and to compute the harmonic wavelet map of a real sequence. This uses an algorithm based on the FFT and, for most problems, is quicker than the dilation wavelet transform. In addition there are programs to compute the musical wavelet transform of a real signal and its inverse and to display the results of this calculation in the form of a musical wavelet map. This has a presentation similar to the musical stave and produces a diagram similar to a sonogram. Instructions on how to obtain the toolbox can be obtained by e-mail request to den@eng.cam.ac.uk. D.E. Newland *MATLAB is a registered trademark of The MathWorks Inc. Professor David Newland Cambridge University Engineering Department Trumpington St Cambridge, CB2 1PZ, UK From: den@eng.cam.ac.uk (David Newland) ************************************************************* ITEM 6 Acoustical Surveillance Conference in Paris - Call for Papers ************************************************************* CALL FOR PAPERS Second International Conference Acoustical and Vibratory Surveillance Methods and Diagnostic Techniques CLAMART (Paris) France October 10-12, 1995 The First International Conference on Acoustical and Vibratory Surveillance Methods (Cetim, Senlis, October 1992), gave a significant overview of the advances recently achieved in these areas. Due to the success of this former conference, and in order to build on it, a second Conference is now being organized. It will be held in Clamart (Paris), France, from October 10th to 12th, 1995, under similar conditions and with the same objectives. This conference is open to the whole community of scientific and industrial specialists in Acoustics, Vibrations, and related domains. Potential authors are invited to send a minimum 500 word abstract, written in French or in English, to SFM before October 15, 1994. Full papers will be needed for publication by June 1, 1995. TOPICS 1 - Methods and tools: acoustics and vibration modelling techniques; signal processing techniques as applied to surveillance problems; statistical methods; decision-making methods; data fusion 2 - Diagnostic techniques: model-based diagnosis and surveillance; adjustment of these methods; expert systems; neural networks; fuzzy logic 3 - Detection problems and their treatment: specific problems such as shaft crack detection, cavitation, leak detection; process surveillance; transient phenomena 4 - Practical means of surveillance: metrology, new transducers, conditioning, signal acquisition and processing; architecture of surveillance systems; associated strategies and softwares 5 - Experience feedback: case studies; technical and economical assessments of surveillance methods Papers and presentations can be given in French or in English. Simultaneous translation will be available. For more information on this conference please contact: Jean FABRI Societe Francaise des Mecaniciens 39-41 rue Louis Blanc F-92400 Courbevoie, FRANCE Tel: (33) 1-47-17-64-89 FAX: (33) 1-47-17-61-31 **************************************************************** ITEM 7 Book Review: NOISE AND VIBRATION CONTROL ENGINEERING **************************************************************** NOISE AND VIBRATION CONTROL ENGINEERING Principles and Applications, Edited by Leo L. Beranek, and Istvan L. Ver, John Wiley & Sons, Inc., ISBN 0-471-61751-2, New York, 1992, 804 pages, $89.95 This book continues in the tradition of its predecessors: NOISE REDUCTION, in 1960 and NOISE AND VIBRATION CONTROL 1971 both edited by Leo L. Beranek and published by McGraw-Hill. Although a few diagrams or figures and four pages of text are repeated from the 1971 book or the 1960 book, the vast majority of the material in the 1992 book is new. This is not surprising since only four of the present 23 chapter authors took part in the writing of the 1971 book. On the whole the book lives up to the high standard of its predecessors. The editors have selected 21 topics as chapters and the authors have largely written in-depth discussions on these topics usually of the order of 20 to 40 pages in length. One exception is Chapter 9 Interaction of Sound Waves with Solid Structures by Istvan L. Ver which stretches to 122 pages (more than one seventh of the whole book). One might express some concern about the length of the chapter and the imbalance it may cause until one realizes that the chapter contains 10 sections dealing with a variety of topics such as: Types of Wave Motion in Solids, Mechanical Impedance, Response of Finite Structures, Power Transmission between Structural Elements, Sound Radiation from Structures, Sound Excitation and Transmission, Statistical Energy Analysis (SEA), Reciprocity, and Impact Noise. Although the book does contain four applied chapters (18-21) on topics such as 1) Machinery Noise, 2) Noise of Internal Combustion Engines (mostly on diesel engines), 3) Noise of Electrical Machinery and 4) Gear Noise, one wonders why two other important topics: Aircraft Noise and Vehicle Noise and their control have received almost no mention in this book. The book does contain two chapters on: 1) Damage Risk Criteria for Hearing and 2) Criteria for Noise and Vibration. Since the first fourteen chapters deal mainly with physical and engineering fundamentals of acoustics and vibration which are on the whole dealt with in a sophisticated manner by well known authors, the fundamental parts of the book are its strength. Its weaknesses include its lack of discussion of many vibrations topics such as modal analysis. On the whole the authors are to be congratulated on producing a valuable book from which engineers can learn physical fundamentals and techniques useful in many engineering noise and vibration problems. Malcolm J. Crocker ****************************************************************