Download or read book Ray and Wave Chaos in Ocean Acoustics written by Denis Makarov and published by World Scientific. This book was released on 2010 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1. Ray and wave propagation. 1.1. Underwater sound channel. 1.2. Basic equations. 1.3. Geometrical optics approximations and optical-mechanical analogy. The Hamiltonian formalism. 1.4. Ray travel times. 1.5. Range-dependent environments. 1.6. Acoustic ocean tomography. 1.7. Experiments on long-range sound propagation. 1.8. Summary -- 2. Ray chaos. 2.1. Hamiltonian chaos. 2.2. Lyapunov instability. 2.3. Ray-medium resonance. 2.4. Overlapping of resonances. 2.5. Vertical resonance. 2.6. Manifestation of regular and chaotic ray motion in distributions of ray travel times. 2.7. Summary -- 3. Wave chaos. 3.1. The problem of wave chaos. 3.2. Normal modes. 3.3. Mode coupling under chaotic conditions. 3.4. Influence of fine-scale inhomogeneities on wave dynamics. 3.5. Summary -- 4. Chaotic phenomena in random environment. 4.1. Ray chaos in a random medium. 4.2. Travel times of chaotic rays. 4.3. Modal structure of the sound field in a waveguide with random inhomogeneities. 4.4. Wave beam in an ocean acoustic waveguide. 4.5. Arrival times of sound pulses in the presence of internal waves and a mesoscale inhomogeneity. 4.6. Summary -- 5. Glossary of some concepts and notations in Hamiltonian chaos theory

Download or read book Ray and Wave Chaos in Ocean Acoustics written by Denis Makarov and published by World Scientific. This book was released on 2010 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Investigating Chaos in Ocean Acoustics written by and published by . This book was released on 1997 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Fundamentals of Ocean Acoustics written by L. Brekhovskikh and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Hamiltonian Chaos Beyond the KAM Theory written by Albert C. J. Luo and published by Springer Science & Business Media. This book was released on 2011-01-04 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: “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.

Download or read book Sound Propagation through the Stochastic Ocean written by John A. Colosi and published by Cambridge University Press. This book was released on 2016-06-20 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean is opaque to electromagnetic radiation and transparent to low frequency sound, so acoustical methodologies are an important tool for sensing the undersea world. Stochastic sound-speed fluctuations in the ocean, such as those caused by internal waves, result in a progressive randomisation of acoustic signals as they traverse the ocean environment. This signal randomisation imposes a limit to the effectiveness of ocean acoustic remote sensing, navigation and communication. Sound Propagation through the Stochastic Ocean provides a comprehensive treatment of developments in the field of statistical ocean acoustics over the last 35 years. This will be of fundamental interest to oceanographers, marine biologists, geophysicists, engineers, applied mathematicians, and physicists. Key discoveries in topics such as internal waves, ray chaos, Feynman path integrals, and mode transport theory are addressed with illustrations from ocean observations. The topics are presented at an approachable level for advanced students and seasoned researchers alike.

Download or read book Fundamentals of Ocean Acoustics written by Leonid M. Brekhovskikh and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: As man turns his attention from the overcrowded continents of this planet and explores the spaciousness of the ocean, the applications of ocean acoustics become increasingly numerous and important. This book pro- vides an up-to-date introduction to the theory of sound propagation in the ocean, with much new material having been added throughout the second edition. It includes both ray and wave treatments and considerable attention is paid to stochastic problems such as the scattering of sound at rough surfaces and random inhomogeneties. An introductory chapter that discusses the basic experimental data complements the following theoretical chapters.

Download or read book New Directions in Linear Acoustics and Vibration written by Matthew Wright and published by Cambridge University Press. This book was released on 2010-07-26 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Linear acoustics was thought to be fully encapsulated in physics texts of the 1950s, but this view has been changed by developments in physics during the last four decades. There is a significant new amount of theory that can be used to address problems in linear acoustics and vibration, but only a small amount of reported work does so. This book is an attempt to bridge the gap between theoreticians and practitioners, as well as the gap between quantum and acoustic. Tutorial chapters provide introductions to each of the major aspects of the physical theory and are written using the appropriate terminology of the acoustical community. The book will act as a quick-start guide to the new methods while providing a wide-ranging introduction to the physical concepts.

Download or read book Fundamentals of Ocean Acoustics written by L. M. Brekhovskikh and published by . This book was released on 2014-01-15 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of Acoustical Oceanography written by Herman Medwin and published by Academic Press. This book was released on 1997-11-05 with total page 739 pages. Available in PDF, EPUB and Kindle. Book excerpt: The developments in the field of ocean acoustics over recent years make this book an important reference for specialists in acoustics, oceanography, marine biology, and related fields. Fundamentals of Acoustical Oceanography also encourages a new generation of scientists, engineers, and entrepreneurs to apply the modern methods of acoustical physics to probe the unknown sea. The book is an authoritative, modern text with examples and exercises. It contains techniques to solve the direct problems, solutions of inverse problems, and an extensive bibliography from the earliest use of sound in the sea to present references.Written by internationally recognized scientists, the book provides background to measure ocean parameters and processes, find life and objects in the sea, communicate underwater, and survey the boundaries of the sea. Fundamentals of Acoustical Oceanography explains principles of underwater sound propagation, and describes how both actively probing sonars and passively listening hydrophones can reveal what the eye cannot see over vast ranges of the turbid ocean. This book demonstrates how to use acoustical remote sensing, variations in sound transmission, in situ acoustical measurements, and computer and laboratory models to identify the physical and biological parameters and processes in the sea. * Offers an integrated, modern approach to passive and active underwater acoustics* Contains many examples of laboratory scale models of ocean-acoustic environments, as well as descriptions of experiments at sea* Covers remote sensing of marine life and the seafloor* Includes signal processing of ocean sounds, physical and biological noises at sea, and inversions* resents sound sources, receivers, and calibration* Explains high intensities; explosive waves, parametric sources, cavitation, shock waves, and streaming* Covers microbubbles from breaking waves, rainfall, dispersion, and attenuation* Describes sound propagation along ray paths and caustics* Presents sound transmissions and normal mode methods in ocean waveguides

Download or read book Ocean and Seabed Acoustics written by George V. Frisk and published by Pearson Education. This book was released on 1994-01-02 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Respected scientist and educator George V. Frisk draws on his extensive professional experience to demonstrate how the ocean environment provides an excellent setting in which to display general principles of wave propagation that are also applicable to other areas of wave physics. Ocean and Seabed Acoustics proceeds with a derivation of elementary solutions to the wave equation in free space and then progressively addresses problems of increasing complexity. This book concludes with a discussion of acoustic wave propagation due to a point source in an inhomogeneous waveguide with lossy boundaries.

Download or read book Ocean Acoustics written by J.A. DeSanto and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Topics volume is devoted to a study of sound propagation in the ocean. The effect of the interior of the ocean on underwater sound is analogous to the effect of a lens on light. The oceanic lens is related, as in light propagation, to the index of refraction of the medium. The latter is giv~n by the ratio of the sound frequency to the speed of sound in water, typi ca lly about 1500 m s -1. It is the vari ation of the sound speed due to changing temperature, density, salinity, and pres sure in the complex ocean environment which creates the lens effect. Many oceanic processes such as currents, tides, eddies (circulating, translating regions of wa ter), and internal waves (the wave-like structure of the oceanic density variabil ity) contri bute in turn to the changes in sound speed'. The net effect of the ocean lens is to trap and guide sound waves in a channel created by the lens. The trapped sound can then propagate thousands of miles in this oceanic waveguide. In addition to the propagation in the interior of the ocean, sound can propagate into and back out of the ocean bottom as well as scatter from the ocean surface. Just as the sound produced by a loudspeaker in a room is affected by the walls of the room, so the ocean boundaries and the material properties below the ocean bottom are essential ingredients in the problem.

Download or read book Using Smoothed Sound Speed To Reduce Chaoticity of Chaos in Ocean Acoustics written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chaos has been shown in the previous project (N00014-95-10443) to exhibit in three-dimensional (3-D) ray tracing for long-range acoustic transmissions in the ocean. It imposes a limitation on our ability to make long-range predictions. We have previously found that the sound speed fluctuations in the upper ocean might be a reason for large chaoticity. Therefore, we inferred that a smoothed sound speed field could reduce chaoticity and thus improve predictability. This hypothesis is tested and confirmed in this project. We still study the Heard-to-Ascension sound propagation, which has shown large chaoticity and extremely limited predictability, in our previous work, when NODC measured sound speed data were used. In this work, the same NODC data were smoothed by using a sound speed model, so that the sound speed fluctuations in both longitude direction and depth direction are ignored. We use the smoothed sound speed to perform 3-D ray tracing. Numerical results show that chaoticity was significantly reduced and consequently predictability greatly improved. The ray paths show a pattern similar to those constructed using the original NODC data. The travel times, however, were less than the previous results by about 10 seconds, with a relative error of 0.16%. This error was produced by the smoothed sound speed.

Download or read book Understanding Ocean Acoustics written by Jens M. Hovem and published by Cambridge Scholars Publishing. This book was released on 2023-10-17 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater acoustics is important in all underwater sonar systems for object detection, classification, surveillance and for communications links for military and civilian purposes. Sound is also a major tool for studying the ocean environment and the interaction of sound and marine life in general. Understanding Ocean Acoustics emphasises such applications and issues relevant to studies of the ocean environment and aquatic life. Its focus is therefore environmental research and development using low frequencies relevant to fish and sea mammals. For such frequencies, the geoacoustic properties of the bottom cannot be ignored, which requires knowledge about waves in solids, which is missing in most books on underwater acoustics.

Download or read book Ocean Variability Acoustic Propagation written by J. Potter and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 599 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fifteen years ago NATO organised a conference entitled 'Ocean Acoustic Modelling'. Many of its participants were again present at this variability workshop. One such participant. in concluding his 1975 paper, quoted the following from a 1972 literature survey: ' ... history presents a sad lack of communications between acousticians and oceanographers' Have we done any better in the last 15 years? We believe so, but only moderately. There is still a massive underdeveloped potential for acousticians and oceanographers to make significant progress together. Currently, the two camps talk together insufficiently even to avoid simple misun derstandings. such as those in Table 1. Table 1 Ocsanographic and acoustic jargon (from an idea by Pol/ardi Jargon Oceanographic use Acoustic use dbordB decibar (depth in m) decibel (energy level) PE primitive equations parabolic equations convergence zone converging currents converging rays (downwelling water) (high energy density) front thermohaline front wave, ray or time front speed water current speed sound propagation speed 1 The list goes on.

Download or read book Chaos Complexity and Transport written by Cristel Chandre and published by World Scientific. This book was released on 2008 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims to provide the readers with a wide panorama of different aspects related to Chaos, Complexity and Transport. It consists of a collection of contributions ranging from applied mathematics to experiments, presented during the CCT'07 conference (Marseilles, June 4-8, 2007). The book encompasses different traditional fields of physics and mathematics while trying to keep a common language among the fields, and targets a nonspecialized audience.

Download or read book Ocean Acoustics written by Ivan Tolstoy and published by . This book was released on 1966 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: