Advances inUnderwater Acoustics


Book Description

Underwater acoustics, despite the relatively short history, has already found practical application in many areas of human activity. It allows, among others, depth research, data transmission, and underwater observation and provides maritime transport safety and security against terrorists. Moreover, underwater acoustic technologies are also widely used in medicine, biology, and many other fields. Therefore, it is one of the most developing areas. This book is a collection of experiences of scientists from around the world engaged in research, design, and construction, as well as the daily use of underwater acoustic systems. Giving this book in the hands of the reader, we hope that it will be a treasure trove of knowledge and inspiration for further research in the field of underwater acoustics.




Mobile Ad Hoc Networking


Book Description

"An excellent book for those who are interested in learning the current status of research and development . . . [and] who want to get a comprehensive overview of the current state-of-the-art." —E-Streams This book provides up-to-date information on research and development in the rapidly growing area of networks based on the multihop ad hoc networking paradigm. It reviews all classes of networks that have successfully adopted this paradigm, pointing out how they penetrated the mass market and sparked breakthrough research. Covering both physical issues and applications, Mobile Ad Hoc Networking: Cutting Edge Directions offers useful tools for professionals and researchers in diverse areas wishing to learn about the latest trends in sensor, actuator, and robot networking, mesh networks, delay tolerant and opportunistic networking, and vehicular networks. Chapter coverage includes: Multihop ad hoc networking Enabling technologies and standards for mobile multihop wireless networking Resource optimization in multiradio multichannel wireless mesh networks QoS in mesh networks Routing and data dissemination in opportunistic networks Task farming in crowd computing Mobility models, topology, and simulations in VANET MAC protocols for VANET Wireless sensor networks with energy harvesting nodes Robot-assisted wireless sensor networks: recent applications and future challenges Advances in underwater acoustic networking Security in wireless ad hoc networks Mobile Ad Hoc Networking will appeal to researchers, developers, and students interested in computer science, electrical engineering, and telecommunications.




Digital Sonar Design in Underwater Acoustics


Book Description

"Digital Sonar Design in Underwater Acoustics Principles and Applications" provides comprehensive and up-to-date coverage of research on sonar design, including the basic theory and techniques of digital signal processing, basic concept of information theory, ocean acoustics, underwater acoustic signal propagation theory, and underwater signal processing theory. This book discusses the general design procedure and approaches to implementation, the design method, system simulation theory and techniques, sonar tests in the laboratory, lake and sea, and practical validation criteria and methods for digital sonar design. It is intended for researchers in the fields of underwater signal processing and sonar design, and also for navy officers and ocean explorers. Qihu Li is a professor at the Institute of Acoustics, Chinese Academy of Sciences, and an academician of the Chinese Academy of Sciences.




Underwater Acoustic Modeling and Simulation


Book Description

Underwater Acoustic Modeling and Simulation, Fourth Edition continues to provide the most authoritative overview of currently available propagation, noise, reverberation, and sonar-performance models. This fourth edition of a bestseller discusses the fundamental processes involved in simulating the performance of underwater acoustic systems and emphasizes the importance of applying the proper modeling resources to simulate the behavior of sound in virtual ocean environments. New to the Fourth Edition Extensive new material that addresses recent advances in inverse techniques and marine-mammal protection Problem sets in each chapter Updated and expanded inventories of available models Designed for readers with an understanding of underwater acoustics but who are unfamiliar with the various aspects of modeling, the book includes sufficient mathematical derivations to demonstrate model formulations and provides guidelines for selecting and using the models. Examples of each type of model illustrate model formulations, model assumptions, and algorithm efficiency. Simulation case studies are also included to demonstrate practical applications. Providing a thorough source of information on modeling resources, this book examines the translation of our physical understanding of sound in the sea into mathematical models that simulate acoustic propagation, noise, and reverberation in the ocean. The text shows how these models are used to predict and diagnose the performance of complex sonar systems operating in the undersea environment.










Underwater Acoustics and Ocean Dynamics


Book Description

These proceedings are a collection of 16 selected scientific papers and reviews by distinguished international experts that were presented at the 4th Pacific Rim Underwater Acoustics Conference (PRUAC), held in Hangzhou, China in October 2013. The topics discussed at the conference include internal wave observation and prediction; environmental uncertainty and coupling to sound propagation; environmental noise and ocean dynamics; dynamic modeling in acoustic fields; acoustic tomography and ocean parameter estimation; time reversal and matched field processing; underwater acoustic localization and communication as well as measurement instrumentations and platforms. These proceedings provide insights into the latest developments in underwater acoustics, promoting the exchange of ideas for the benefit of future research.




An Introduction to Underwater Acoustics


Book Description

Presented in a clear and concise way as an introductory text and practical handbook, the book provides the basic physical phenomena governing underwater acoustical waves, propagation, reflection, target backscattering and noise. It covers the general features of sonar systems, transducers and arrays, signal processing and performance evaluation. It provides an overview of today's applications, presenting the working principles of the various systems. From the reviews: "Presented in a clear and concise way as an introductory text and practical handbook, the book provides the basic physical phenomena governing underwater acoustical waves, propagation, reflection, target backscattering and noise. ⦠It provides an overview of todayâs applications, presenting the working principles of the various systems." (Oceanis, Vol. 27 (3-4), 2003) "This book is a general survey of Underwater Acoustics, intended to make the subject âas easily accessible as possible, with a clear emphasis on applications.â In this the author has succeeded, with a wide variety of subjects presented with minimal derivation ⦠. There is an emphasis on technology and on intuitive physical explanation ⦠." (Darrell R. Jackson, Journal of the Acoustic Society of America, Vol. 115 (2), February, 2004) "This is an exciting new scientific publication. It is timely and welcome ⦠. Furthermore, it is up to date and readable. It is well researched, excellently published and ranks with earlier books in this discipline ⦠. Many persons in the marine science field including acousticians, hydrographers, oceanographers, fisheries scientists, engineers, educators, students ⦠and equipment manufacturers will benefit greatly by reading all or part of this text. The author is to be congratulated on his fine contribution ⦠." (Stephen B. MacPhee, International Hydrographic Review, Vol. 4 (2), 2003)




Sonar and Underwater Acoustics


Book Description

Sonar and Underwater Acoustics brings together all the concepts necessary for designers and users of sonar systems. Unlike other books on this subject, which are often too specialized, this book is accessible to a wider audience. The first part focuses on the acoustic environment, antenna structures, and electric acoustic interface. The latter provides knowledge required to design, as well as the development and implementation of chain processes for an active sonar from the conditioning input to output processing. The reader will find a comprehensive range of all problems encountered in underwater acoustics for a sonar application, from physical phenomena governing the environment and the corresponding constraints, through to the technical definition of transducers and antennas, and the types of signal processing involved. In one section, measures in underwater acoustics are also proposed.




Progress in Underwater Acoustics


Book Description

IMAGE TRACKS AT HALIFAX by L.B. Felsen All living kind much effort spend Some model modes, some model rays, To cope with their environment Some feel that spectra all portrays. Some use their eyes, some use their nose Then there are those who with despatch, To sense where other things repose. Take refuge in the ocean wedge. For one group, nothing's more profound Than to explore the world with sound. If things get messy, randomize. These audio diagnosticians What's partly smooth, determinize. You ponder, is it this or that? Go by the name of acousticians. And wish you were a lowly bat They regularly meet to check Whether their sonogram's on track. The meeting's hosts did treat us well. With images stored in their packs, They let the climate cast its spell. This year they came to Halifax. No weath'ry hope was placed in vain. There they combined with ocean types We were exposed to wind and rain, And each could hear the other's gripes. We glimpsed blue sky through clouds dispersed. A meeting naturally does start But rainy sequence was reversed: Reviewing present state of art. The ocean types would like it wet What we found out is where it's at: Yet they got stuck with sun instead. We cannot hope to match the bat Each confrence has the same refrain: Computer printouts by the reams It has been fun to meet again.