Investigating Chaos in Ocean Acoustics

Investigating Chaos in Ocean Acoustics PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 91

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Book Description
Chaos is a term assigned to a class of motions in deterministic systems whose time history has a sensitive dependence on initial conditions. Such phenomenon has previously been shown to exhibit in ocean acoustics ray tracing, and called ray chaos by the ocean acoustics community. Since 1995, we have made a further investigation on the ray chaos, as a basic research sponsored by the Office of Naval Research (Grant No. N00014-95-10443). The results of this investigation are presented in this report. Two new topics are addressed. The first is the chaos in three-dimensional (3-D) ray tracing. We study the chaos in Heard-to-Ascension (HA) propagation, and California-to-Hawaii (CH) propagation. Chaos appeared in both cases. Loss of predictability occurred in HA case. However, CH problem was predicted with high accuracy even in the presence of chaos. Comparison between the HA and the CH case leads to a hypothesis on overcoming ray chaos. The signature of chaos in the received signals is discussed. The second topic is the chaos in double-channel propagation. We use the 2-D equations and a double-channel model to study the effects of internal waves on chaos. Then we use the 3-D ray equations and measured sound speed data to conduct a further investigation. Numerical results show that chaos in a double-channel is likely to be induced by internal waves. Much larger chaoticity was observed when measured sound speed data were used.

Ray and Wave Chaos in Ocean Acoustics

Ray and Wave Chaos in Ocean Acoustics PDF Author: Denis Makarov
Publisher: World Scientific
ISBN: 9814273171
Category : Science
Languages : en
Pages : 412

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Book Description
A systematic study of chaotic ray dynamics in underwater acoustic waveguides began in the mid-1990s when it was realized that this factor plays a crucial role in long-range sound propagation in the ocean. The phenomenon of ray chaos and its manifestation at a finite wavelength ? wave chaos ? have been investigated by combining methods from the theory of wave propagation and the theory of dynamical and quantum chaos. This book is the first monograph summarizing results obtained in this field. Emphasis is made on the exploration of ray and modal structures of the wave field in an idealized environmental model with periodic range dependence and in a more realistic model with sound speed fluctuations induced by random internal waves. The book is intended for acousticians investigating the long-range sound transmission through the fluctuating ocean and also for researchers studying waveguide propagation in other media. It will be of major interest to scientists working in the field of dynamical and quantum chaos.

Ocean Acoustics

Ocean Acoustics PDF Author: Anatoly Kistovich
Publisher: Springer Nature
ISBN: 3030358844
Category : Science
Languages : en
Pages : 171

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Book Description
This book presents a comprehensive overview of hydroacoustics and describes the physical basis of acoustic processes observed in the sea. In addition, it discusses the basic concepts and provides simplified models of sound propagation and acoustic phenomena at the boundary between environments. Lastly, the book examines in detail a number of applications of ocean acoustics and methods. The ocean is the last reserve of natural resources. It is also an essential element in the biosphere, ensuring the latter’s balance, and plays a pivotal role in the Earth’s climate system and global warming. Consequently, studying the ocean is one of humankind’s most critical scientific tasks, but penetrating its mysteries is no mean feat. Acoustics (hydroacoustics) is one of the most powerful tools for examining the water layer and beyond, since sound waves are the only type of radiation that can propagate over distances of hundreds and even thousands of kilometers in the ocean. This unique resource appeals to specialists working in the fields of ocean and atmosphere physics, students and postgraduate students studying sea physics and oceanology, and anyone who is interested in the problems the ocean is currently facing.

Fundamentals of Ocean Acoustics

Fundamentals of Ocean Acoustics PDF Author: L. Brekhovskikh
Publisher: Springer Science & Business Media
ISBN: 3662023423
Category : Science
Languages : en
Pages : 262

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Book Description
The continents of our planet have already been exploited to a great extent. Therefore man is turning his sight to the vast spaciousness of the ocean whose resources - mineral, biological, energetic, and others - are just beginning to be used. The ocean is being intensively studied. Our notions about the dynam ics of ocean waters and their role in forming the Earth's climate as well as about the structure of the ocean bottom have substantially changed during the last two decades. An outstanding part in this accelerated exploration of the ocean is played by ocean acoustics. Only sound waves can propagate in water over large distances. Practically all kinds of telemetry, communication, location, and re mote sensing of water masses and the ocean bottom use sound waves. Propa gating over thousands of kilometers in the ocean, they bring information on earthquakes, eruptions of volcanoes, and distant storms. Projects using acoustical tomography systems for exploration of the ocean are presently be ing developed. Each of these systems will allow us to determine the three-di mensional structure of water masses in regions as large as millions of square kilometers.

Hamiltonian Chaos Beyond the KAM Theory

Hamiltonian Chaos Beyond the KAM Theory PDF Author: Albert C. J. Luo
Publisher: Springer Science & Business Media
ISBN: 3642127185
Category : Science
Languages : en
Pages : 312

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Book Description
“Hamiltonian Chaos Beyond the KAM Theory: Dedicated to George M. Zaslavsky (1935—2008)” covers the recent developments and advances in the theory and application of Hamiltonian chaos in nonlinear Hamiltonian systems. The book is dedicated to Dr. George Zaslavsky, who was one of three founders of the theory of Hamiltonian chaos. Each chapter in this book was written by well-established scientists in the field of nonlinear Hamiltonian systems. The development presented in this book goes beyond the KAM theory, and the onset and disappearance of chaos in the stochastic and resonant layers of nonlinear Hamiltonian systems are predicted analytically, instead of qualitatively. The book is intended for researchers in the field of nonlinear dynamics in mathematics, physics and engineering. Dr. Albert C.J. Luo is a Professor at Southern Illinois University Edwardsville, USA. Dr. Valentin Afraimovich is a Professor at San Luis Potosi University, Mexico.

Investigation of Ocean Acoustics Using Autonomous Instrumentation to Quantify the Water-sediment Boundary Properties

Investigation of Ocean Acoustics Using Autonomous Instrumentation to Quantify the Water-sediment Boundary Properties PDF Author: Jason David Holmes
Publisher:
ISBN:
Category : Marine sediments
Languages : en
Pages : 630

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Book Description


Underwater Acoustic Modeling

Underwater Acoustic Modeling PDF Author: P.C. Etter
Publisher: CRC Press
ISBN: 9780419201908
Category : Architecture
Languages : en
Pages : 364

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Book Description
Underwater Acoustic Modeling provides the only comprehensive source on how to translate our physical understanding of sound in the sea into mathematical formulas solvable by computers.

Underwater Acoustic Modelling and Simulation, Third Edition

Underwater Acoustic Modelling and Simulation, Third Edition PDF Author: P.C. Etter
Publisher: CRC Press
ISBN: 0203417658
Category : Technology & Engineering
Languages : en
Pages : 447

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Book Description
Underwater Acoustic Modeling and Simulation examines the translation of our physical understanding of sound in the sea into mathematical models that can simulate acoustic propagation, noise and reverberation in the ocean. These models are used in a variety of research and operational applications to predict and diagnose the performance of complex sonar systems operating in the undersea environment. Previous editions of the book have provided invaluable guidance to sonar technologists, acoustical oceanographers and applied mathematicians in the selection and application of underwater acoustic models. Now that simulation is fast becoming an accurate, efficient and economical alternative to field-testing and at-sea training, this new edition will also provide useful guidance to systems engineers and operations analysts interested in simulating sonar performance. Guidelines for selecting and using available propagation, noise and reverberation models are highlighted. Specific examples of each type of model are discussed to illustrate model formulations, assumptions and algorithm efficiency. Instructive case studies demonstrate applications in sonar simulation.

Underwater Acoustic Modelling and Simulation

Underwater Acoustic Modelling and Simulation PDF Author: P.C. Etter
Publisher: CRC Press
ISBN: 1482295148
Category : Technology & Engineering
Languages : en
Pages : 447

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Book Description
Underwater Acoustic Modeling and Simulation examines the translation of our physical understanding of sound in the sea into mathematical models that can simulate acoustic propagation, noise and reverberation in the ocean. These models are used in a variety of research and operational applications to predict and diagnose the performance of complex s

Underwater Acoustics and Ocean Dynamics

Underwater Acoustics and Ocean Dynamics PDF Author: Lisheng Zhou
Publisher: Springer
ISBN: 9811024227
Category : Science
Languages : en
Pages : 126

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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.