Acoustical Imaging

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Acoustical Imaging

Author : Helmut Ermert
Publisher : Springer Science & Business Media
ISBN 13 : 1461533708
Total Pages : 918 pages
Book Rating : 4.4/5 (615 download)

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Book Synopsis Acoustical Imaging by : Helmut Ermert

Download or read book Acoustical Imaging written by Helmut Ermert and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 918 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the proceedings of the 19th International Symposium on Acoustical Imaging at the Ruhr-University Bochum, Germany during April 3 -5, 1991. It was the first time that the symposium was held in Europe after major political changes happened in that area. The freedom to travel for all people from eastern European countries was an obvious reason for the great numbers of sub mitted abstracts and for numerous conference participants. 193 of 239 submitted contributions from 29 countries were accepted for presentation by authors from USA (13%), Canada (2%), Japan (7%), Peoples Republic of China (7%), United Kingdom (4%), France (7%), Italy (3%), Poland (4%), Soviet Union (7%), Germany (28%) and other countries (18%). 283 scientists from 29 countries attended the conference representing the interdisciplinary field between mathematics, physics, engineering and medicine. 151 papers were available for publication in this proceedings covering the topics 1. Mathematics and Physics of Acoustical Imaging 2. Components and Systems 3. Applications in Medicine and Biology 4. Applications in Nondestructive Testing 5. Remote Sensing Applications 6. Industrial Applications A relative large number of contributions on acoustical microscopy was included in the conference program within topics 3 and 4. Also, papers on "non-traditional" acoustical imaging subjects, e. g. on phonon imaging and on remote sensing in the atmosphere, have broadened the scope of the conference. The success and stimulation of the conference and of the papers presented in this volume is owed, of course to the authors and participants.

Acoustical Imaging

Author : John Powers
Publisher : Springer
ISBN 13 : 9780306409882
Total Pages : 0 pages
Book Rating : 4.4/5 (98 download)

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Book Synopsis Acoustical Imaging by : John Powers

Download or read book Acoustical Imaging written by John Powers and published by Springer. This book was released on 1982-10-01 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains forty-one papers presented at the Eleventh International Symposium on Acoustical Imaging held on 4-7 Ma~ in Monterey, California. The objective of this conference series is to bring together workers in diverse areas and applications of Acoustical Imaging for interaction and exchange of ideas. People working in other aspects of scalar wave theory and applications also benefit from this series. The papers presented here demonstrate continued growth in the activity of this field. In this conference there was emphasis on New Techniques, Acoustic Tomography, Tissue Characterization, Signal Processing, Inversion Techniques, and Transducers and Arrays. The success and stimulation of the conference and of the papers presented in this volume is owed, of course to the authors and participants. Many thanks are due to the authors and their co-workers for their diligence and enthusiasm in performing their research, preparing their manuscripts and presenting their results. The editor would like to express his appreciation to each and every one of them.

Acoustical Imaging

Author : Woon Siong Gan
Publisher : John Wiley & Sons
ISBN 13 : 0470661607
Total Pages : 437 pages
Book Rating : 4.4/5 (76 download)

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Book Synopsis Acoustical Imaging by : Woon Siong Gan

Download or read book Acoustical Imaging written by Woon Siong Gan and published by John Wiley & Sons. This book was released on 2012-07-23 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technology of acoustical imaging has advanced rapidly over the last sixty years, and now represents a sophisticated technique applied to a wide range of fields including non-destructive testing, medical imaging, underwater imaging and SONAR, and geophysical exploration. Acoustical Imaging: Techniques and Applications for Engineers introduces the basic physics of acoustics and acoustical imaging, before progressing to more advanced topics such as 3D and 4D imaging, elasticity theory, gauge invariance property of acoustic equation of motion and acoustic metamaterials. The author draws together the different technologies in sonar, seismic and ultrasound imaging, highlighting the similarities between topic areas and their common underlying theory. Key features: Comprehensively covers all of the important applications of acoustical imaging. Introduces the gauge invariance property of acoustic equation of motion, with applications in the elastic constants of isotropic solids, time reversal acoustics, negative refraction, double negative acoustical metamaterial and acoustical cloaking. Contains up to date treatments on latest theories of sound propagation in random media, including statistical treatment and chaos theory. Includes a chapter devoted to new acoustics based on metamaterials, a field founded by the author, including a new theory of elasticity and new theory of sound propagation in solids and fluids and tremendous potential in several novel applications. Covers the hot topics on acoustical imaging including time reversal acoustics, negative refraction and acoustical cloaking. Acoustical Imaging: Techniques and Applications for Engineers is a comprehensive reference on acoustical imaging and forms a valuable resource for engineers, researchers, senior undergraduate and graduate students.

Acoustical Imaging

Author : Iwaki Akiyama
Publisher : Springer Science & Business Media
ISBN 13 : 140208823X
Total Pages : 503 pages
Book Rating : 4.4/5 (2 download)

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Book Synopsis Acoustical Imaging by : Iwaki Akiyama

Download or read book Acoustical Imaging written by Iwaki Akiyama and published by Springer Science & Business Media. This book was released on 2010-11-03 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works. Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: (1) Strain Imaging, (2) Biological and Medical Applications, (3) Acoustic Microscopy, (4) Non-Destructive Evaluation and Industrial Applications, (5) Components and Systems, (6) Geophysics and Underwater Imaging, (7) Physics and Mathematics, (8) Medical Image Analysis, (9) FDTD method and Other Numerical Simulations.

Acoustical Imaging

Author : Michael P. André
Publisher : Springer Science & Business Media
ISBN 13 : 9789048132553
Total Pages : 399 pages
Book Rating : 4.1/5 (325 download)

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Book Synopsis Acoustical Imaging by : Michael P. André

Download or read book Acoustical Imaging written by Michael P. André and published by Springer Science & Business Media. This book was released on 2011-07-24 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the course of the years the volumes in the Acoustical Imaging Series have developed to become well-known and appreciated reference works. Offering both a broad perspective on the state of the art in the field as well as an in-depth look at its leading edge research, this Volume 30 in the Series contains again an excellent collection of contributions, presented in five major categories:

Acoustical Imaging

Author : Keith Wang
Publisher : Springer Science & Business Media
ISBN 13 : 1468437550
Total Pages : 829 pages
Book Rating : 4.4/5 (684 download)

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Book Synopsis Acoustical Imaging by : Keith Wang

Download or read book Acoustical Imaging written by Keith Wang and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 829 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains forty-six of the papers presented at the Ninth International Symposium on Acoustical Imaging held December 3-6, 1979, in Houston, Texas. The theme of the confer ence was the integration of applications technology. The major objective of the conference was to promote interaction among researchers working on different applications of acoustical imaging. In addition to serving as a state-of-the-art research ref erence, this volume includes six tutorial review papers. For convenience, all the papers are grouped under the following headings: methods, transducers, processing and display, phased array considerations, acoustic microscopy/non-destructive evalu ation, reconstructive tomography and inversion techniques, tissue characterization and impediography, nedica1 applications, under water applications, and seismic applications. The editor would like to thank the authors and the confer ence participants. The editor would also like to express his appreciation for the assistance in evaluating the abstracts from the following members of the Program Committee: Mahfuz Ahmed, University of California Irvine l:1edica1 Center; Pierre A1ais, Paris University, France; C.B. Burckhardt, Hoffman-Laroche, Basel, Switzerland; B.P. Hildebrand, Spectron Development Labora tories, Inc., Costa Mesa, California; Larry W. Kessler, Sonoscan, Inc., Bensenville, Illinois; Rolf Uue11er, University of Hinnesota, l1inneapo1is, Uinnesota; John P. Powers, Naval Post Graduate School, J:1onterey, California; Jerry L. Sutton, Naval Ocean Systems Center, San Diego, California; F.L. Thurstone, Duke University, Durham, North Carolina; Robert C. Waag, University of Rochester, Rochester, New York; and Glen Wade, University of California, Santa Barbara, California.

Acoustical Imaging

Author : M. Kaveh
Publisher : Springer Science & Business Media
ISBN 13 : 1461327792
Total Pages : 589 pages
Book Rating : 4.4/5 (613 download)

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Book Synopsis Acoustical Imaging by : M. Kaveh

Download or read book Acoustical Imaging written by M. Kaveh and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume constitutes the proceedings of the Thirteenth Inter national Symposium on Acoustical Imaging which was held in Minneapolis, Minnesota during October 26-28, 1983. Forty-eight research papers were presented during the meeting by researchers from twelve countries, again demonstrating the true international character of these meetings. Of these presentations this volume contains forty-two complete manuscripts. The abstracts for addi tional papers that were not available at publication time are also included. According to the recent tradition of these symposia an inter disciplinary program under the general theme of acoustical imaging was organized. This can clearly be observed from the wide range of topics and approaches contained in the following manuscripts. There are papers of mathematical nature dealing with the basis of image formation and algorithms for digitally carrying out specific imaging tasks. One finds manuscripts dealing with the design and construction of imaging transducers as well as complete imaging systems. Applications include medical imaging and nondestructive testing, seismic and underwater imaging. This volume, therefore, should be of interest to active researchers in acoustical imaging as a report on current research and to workers in signal process ing, sonics and ultrasonics who are interested in exploring the diverse areas of application for their fields of interest. These proceedings are organized in seven topical sections, paral leling the sessions of the conference. These are: Inversion and Tomography, Microscopy, Scattering and Propagation, Tissue and Material Characterization, Signal Processing, Transducers and Arrays, Imaging Systems and Special Techniques.

Acoustical Imaging

Author : Walter Arnold
Publisher : Springer Science & Business Media
ISBN 13 : 9781402024016
Total Pages : 802 pages
Book Rating : 4.0/5 (24 download)

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Book Synopsis Acoustical Imaging by : Walter Arnold

Download or read book Acoustical Imaging written by Walter Arnold and published by Springer Science & Business Media. This book was released on 2004-09-16 with total page 802 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustical imaging has become an indispensable tool in a variety of fields. Since its introduction, the applications have grown and cover a variety of techniques, producing significant results in fields as disparate as medicine and seismology. Cutting-edge trends continue to be discussed worldwide. This book contains the proceedings of the 27th International Symposium on Acoustical Imaging (AI27), which took place in Saarbrücken, Germany, from March 24th to March 27th 2003. The Symposium belongs to a conference series in existence since 1968. AI27 comprised sessions on: Medical Imaging, Non-Destructive Testing, Seismic Imaging, Physics and Mathematics of Acoustical Imaging, Acoustic Microscopy. During two well-attended workshops the applications of quantitative acoustical imaging in biology and medical applications, and in near-field imaging of materials, were discussed. Based on its cross-disciplinary aspects, the authors of the papers of AI27 present experiments, theory and construction of new instruments.

Acoustical Imaging

Author : John P. Powers
Publisher : Springer Science & Business Media
ISBN 13 : 1468411373
Total Pages : 647 pages
Book Rating : 4.4/5 (684 download)

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Book Synopsis Acoustical Imaging by : John P. Powers

Download or read book Acoustical Imaging written by John P. Powers and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 647 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains forty-one papers presented at the Eleventh International Symposium on Acoustical Imaging held on 4-7 Ma~ in Monterey, California. The objective of this conference series is to bring together workers in diverse areas and applications of Acoustical Imaging for interaction and exchange of ideas. People working in other aspects of scalar wave theory and applications also benefit from this series. The papers presented here demonstrate continued growth in the activity of this field. In this conference there was emphasis on New Techniques, Acoustic Tomography, Tissue Characterization, Signal Processing, Inversion Techniques, and Transducers and Arrays. The success and stimulation of the conference and of the papers presented in this volume is owed, of course to the authors and participants. Many thanks are due to the authors and their co-workers for their diligence and enthusiasm in performing their research, preparing their manuscripts and presenting their results. The editor would like to express his appreciation to each and every one of them.

Acoustical Imaging

Author : A.F. Metherell
Publisher : Springer Science & Business Media
ISBN 13 : 1461329434
Total Pages : 778 pages
Book Rating : 4.4/5 (613 download)

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Book Synopsis Acoustical Imaging by : A.F. Metherell

Download or read book Acoustical Imaging written by A.F. Metherell and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 778 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the Proceedings of the Eighth International Symposium on Acoustical Imaging, held in Key Biscayne, Miami, Florida May 29th to June 2nd, 1978. The title of the Symposium was changed again this year by dropping the word "Holography" to reflect the further emphasis on the general imaging aspects of the Symposium and the de-emphasis on the Holographic aspects. Because of this continued changing nature of the Symposium Series this volume has undergone the title change from ACOUSTICAL HOLOGRAPHY to ACOUSTICAL IMAGING. The 47 papers presented here illustrate the continued growth in this dynamic field. There has been a large emphasis on Array Technology as well as Underwater Applications, Seismic Applications, Transducers, New Methods, Acoustic Microscopy, Non-destructive Testing, Computer Tomography Techniques, Medical Applications as well as Tissue Characterization. The meeting was a great success and a stimulating experience for all concerned due principally to the enthusiasm and contrib utions of all of the authors represented here. The editor wishes to extend his appreciation and thanks to each and everyone of them. The editor also wishes to thank the members of the Program Committee who helped in selecting the papers and giving their able advice on the details of the meeting. The Program Committee con sisted of Pierre Alais, University of Paris, Byron B. Brendon, Holosonics, Inc. , C. B. Burckhardt, Hoffman-LaRoche and Co. , Basle, Switzerland, Philip S. Green, Stanford Research Institute, Menlo Park, California, B. P.

Acoustical Imaging

Author : Yu Wei
Publisher : Springer Science & Business Media
ISBN 13 : 1461529581
Total Pages : 767 pages
Book Rating : 4.4/5 (615 download)

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Book Synopsis Acoustical Imaging by : Yu Wei

Download or read book Acoustical Imaging written by Yu Wei and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 105 theses contained in this book are selected from those whose authors were present at the 20th International Symposium on Acoustical Imaging. held at Southeast University. Nanjing. China. during September 12-14. 1992. It was the first time that the symposium had been held in China. Our efforts to host the conference goes back to the 15th International Symposium on Acoustical Imaging held in Halifax. Canada. in 1986. We are glad that the 20th symposium has been successfully held at last. We are ardent for the symposium not only because we attach much importance to the field of acoustical imaging. but also because we admire the tradition of the serious academic exploration and friendly cooperation of the scholars attending the symposium. The theses in this book are from 21 countries and those by Mr. G. Wade. Takuso Sato. J. F. Greenleaf. K. J. Langenberg. and Wencai Yang are the specially invited papers. These theses cover such important fields of acoustical imaging as follows: 1. Mathematics and physics of acoustical imaging; 2. Components and industry application; 3. Applications in medicine and biology; 4. Applications in nondestructive testing; 5. Applications in geophysics; 6. Underwater acoustical imaging. All these theses reflect the latest progress in theory and technology. We are very grateful to all the authors who have provided these theses.

Acoustical Imaging

Author : Woon Siong Gan
Publisher : John Wiley & Sons
ISBN 13 : 1119941717
Total Pages : 437 pages
Book Rating : 4.1/5 (199 download)

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Book Synopsis Acoustical Imaging by : Woon Siong Gan

Download or read book Acoustical Imaging written by Woon Siong Gan and published by John Wiley & Sons. This book was released on 2012-05-11 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technology of acoustical imaging has advanced rapidly over the last sixty years, and now represents a sophisticated technique applied to a wide range of fields including non-destructive testing, medical imaging, underwater imaging and SONAR, and geophysical exploration. Acoustical Imaging: Techniques and Applications for Engineers introduces the basic physics of acoustics and acoustical imaging, before progressing to more advanced topics such as 3D and 4D imaging, elasticity theory, gauge invariance property of acoustic equation of motion and acoustic metamaterials. The author draws together the different technologies in sonar, seismic and ultrasound imaging, highlighting the similarities between topic areas and their common underlying theory. Key features: Comprehensively covers all of the important applications of acoustical imaging. Introduces the gauge invariance property of acoustic equation of motion, with applications in the elastic constants of isotropic solids, time reversal acoustics, negative refraction, double negative acoustical metamaterial and acoustical cloaking. Contains up to date treatments on latest theories of sound propagation in random media, including statistical treatment and chaos theory. Includes a chapter devoted to new acoustics based on metamaterials, a field founded by the author, including a new theory of elasticity and new theory of sound propagation in solids and fluids and tremendous potential in several novel applications. Covers the hot topics on acoustical imaging including time reversal acoustics, negative refraction and acoustical cloaking. Acoustical Imaging: Techniques and Applications for Engineers is a comprehensive reference on acoustical imaging and forms a valuable resource for engineers, researchers, senior undergraduate and graduate students.

Acoustical Imaging

Author : Walter Arnold
Publisher : Springer Science & Business Media
ISBN 13 : 1402024029
Total Pages : 761 pages
Book Rating : 4.4/5 (2 download)

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Book Synopsis Acoustical Imaging by : Walter Arnold

Download or read book Acoustical Imaging written by Walter Arnold and published by Springer Science & Business Media. This book was released on 2013-06-05 with total page 761 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustical imaging has become an indispensable tool in a variety of fields. Since its introduction, the applications have grown and cover a variety of techniques, producing significant results in fields as disparate as medicine and seismology. Cutting-edge trends continue to be discussed worldwide. This book contains the proceedings of the 27th International Symposium on Acoustical Imaging (AI27), which took place in Saarbrücken, Germany, from March 24th to March 27th 2003. The Symposium belongs to a conference series in existence since 1968. AI27 comprised sessions on: Medical Imaging, Non-Destructive Testing, Seismic Imaging, Physics and Mathematics of Acoustical Imaging, Acoustic Microscopy. During two well-attended workshops the applications of quantitative acoustical imaging in biology and medical applications, and in near-field imaging of materials, were discussed. Based on its cross-disciplinary aspects, the authors of the papers of AI27 present experiments, theory and construction of new instruments.

Acoustical Imaging

Author : Michael Halliwell
Publisher : Springer Science & Business Media
ISBN 13 : 0306471078
Total Pages : 565 pages
Book Rating : 4.3/5 (64 download)

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Book Synopsis Acoustical Imaging by : Michael Halliwell

Download or read book Acoustical Imaging written by Michael Halliwell and published by Springer Science & Business Media. This book was released on 2006-05-26 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: The origin ofthe International Acoustical Imaging Symposium series can be traced to 1967, when a meeting on acoustical holography was held in C alifornia. In those days, acoustical holography was at the leading edge of research but, as the importance of this subject waned, so the title of the series was changed from Acoustical Holography to Acoustical Imaging in 1978. The early Symposia were held at various venues in the United States. In 1980. the series became international, with the Symposium that year taking place in Cannes in France. The pattern now is to try to met alternately in the USA and in another part of the world so that active researchers everywhere can conveniently attend at a reasonably high frequency. It was a great privilege for us in Bristol in the United Kingdom to be chosen to host the 25th Symposium, which convened on 19 March 2000 and spread over four days. We were blessed not only by good weather, but also by the attendance ofnearly 100 pa rticipants who came from 17 c ountries. A large number of papers were accepted for presentation, either orally or as posters. Whether an oral presentation or a poster, all were considered to have equal merit, and no distinction is made between them in the published proceedings. There were no parallel sessions, so every participant could attend every presentation. The re sultant disciplinary cross fertilisation maintained the t radition of past Symposia.

Acoustical Imaging

Author : Hugh W. Jones
Publisher : Springer Science & Business Media
ISBN 13 : 1468453203
Total Pages : 670 pages
Book Rating : 4.4/5 (684 download)

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Book Synopsis Acoustical Imaging by : Hugh W. Jones

Download or read book Acoustical Imaging written by Hugh W. Jones and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 15 follows the format of earlier volumes in the series. The contents give the next installment in the varied aspects of acoustical imaging research. On this occasion, some emphasis was placed on the rela tionship of l1nderwater acoustics to acoustical imaging and a volume of papers under the title "Underwater Acoustics Proceedings from the 12th ICA Symposium held in Halifax," will appear at roughly the same time as this volume. There is no duplication in these volumes but they are in terlinked, at least to the extent that papers from common conference sessions appear in one or another volume. An innovation is the review paper presented at the beginning of the volume "A History of Acoustical Imaging," by G Wade. This fairly detailed review comes at a point in time when so much has been achieved and in some cases passed by, that a record of some of the earlier work might help to keep a balance with the large collections of research papers which have appeared in the many volumes.

Acoustical Imaging

Author : Eric Ash
Publisher : Springer Science & Business Media
ISBN 13 : 1461397804
Total Pages : 758 pages
Book Rating : 4.4/5 (613 download)

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Book Synopsis Acoustical Imaging by : Eric Ash

Download or read book Acoustical Imaging written by Eric Ash and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 758 pages. Available in PDF, EPUB and Kindle. Book excerpt: The formation of images by ultrasound is a fascinating study, with well-established, yet rapidly growing, applic ations in medicine and with increasing relevance to a surprisingly disparate set of problems in the non-destructive examination of materials and components. The present volume is a record of the research presented at the Twelfth International Symposium on Acoustic Imaging, held in London during July 1982. Whilst, therefore, it offers primarily a snap-shot in time of a rapidly developing field, it is so organized that it will also serve as a high-speed entry into the literature for someone embarking, for the first time, on· researches in this branch of applied science. As in previous volumes, some of the work reported is concerned with topics which, whilst of critical importance to the performance of any imaging system, - e.g. transducers, signal processing may not address themselves to image formation per se. A new departure is the inclusion of photo-acoustic imaging a subject of rapidly growing importance for many of the same application areas relevant to acoustical imaging.

Acoustical Imaging

Author : Sydney Lees
Publisher : Springer Science & Business Media
ISBN 13 : 1441985883
Total Pages : 651 pages
Book Rating : 4.4/5 (419 download)

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Book Synopsis Acoustical Imaging by : Sydney Lees

Download or read book Acoustical Imaging written by Sydney Lees and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 651 pages. Available in PDF, EPUB and Kindle. Book excerpt: The contents of this volume are the proceedings of the 23'd International Symposium on Acoustical Imaging which took place 13-16 April, 1997, in Boston, Massachusetts. The first Symposium met 25 years ago. Originally the Symposium met in California, then elsewhere within the United States but beginning in 1988 the Symposia began to meet outside of the United States as welL It is now being held about every eighteen months, alternately in the United States and then outside. The present pattern is to hold one meeting in East Asia, then in the USA, then in Europe and again in the USA However, for scheduling reasons the next Symposium will be in Santa Barbara, California, followed by England and then East Asia. It is to be noted that the Symposium is a free standing institution, not associated with any other organization. Each meeting is the total responsibility of its chairman with the advice of past chairmen. Papers are submitted in response to the call for them and reviewed by an International Scientific Advisory Board . . The quality depends entirely on the response to the calL It is gratifYing to note that the Symposium has attained the status that attracts high quality contributions despite (or perhaps because ot) the loose structure. Two factors that have appeal are that there is only one session and that there is time during the meeting for extensive discussion.