Ocean Acoustics Program
Author: J. Michael McKisic
Publisher:
Published: 1981
Total Pages: 108
ISBN-13:
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Ocean Acoustics Program Summary for FY's 83 and 84
Author: J McKisic (Michael)
Publisher:
Published: 1985
Total Pages: 191
ISBN-13:
DOWNLOAD EBOOKOcean Acoustics
Author: J.A. DeSanto
Publisher: Springer Science & Business Media
Published: 2013-11-11
Total Pages: 295
ISBN-13: 3642812945
DOWNLOAD EBOOKThis 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.
Report of a Survey of US Academic Programs in Ocean and Underwater Acoustics
Author: K. W. Lackie
Publisher:
Published: 1997
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOKUnderwater acoustics remains the principal means to detect and locate submarines and other underwater objects. For this reason, the Office of Naval Research has sponsored a vigorous research program in underwater acoustics and related fields at both academic institutions and Navy in house organizations for many years. Unfortunately, no other Federal Government funding agency sponsors research in this area, and as a result the health, strength, and growth of the field in the US depends entirely on the ONR program. Interviews of senior U.S. acoustician and visits to a number of major institutions indicate that recent reductions in Naval research budgets have caused a significant decline in the vitality of the ocean acoustics research community in the U.S., especially in its capability to train graduate students in at sea experimental techniques and maintain its sea going infrastructure. Although a number of initiatives are identified that would improve the situation, only an increase in financial support will completely solve the problem. The current level of Federal funding is inadequate to support long-term Navy requirements for acoustician, though it may be adequate for the current environment of reduced budgets and priorities. The strength of this field, virtually the only one entrusted entirely to ONR's care, is not being sustained.
Ocean Acoustics Education and Expertise
Author: National Academies of Sciences Engineering and Medicine
Publisher:
Published: 2025-04-23
Total Pages: 0
ISBN-13: 9780309706872
DOWNLOAD EBOOKOcean Acoustics - the study of sound in the ocean, how it travels, interacts with, and is affected by its underwater surroundings - is a growing and critical field. Sound from both natural and human-generated sources can be an effective tool for probing the ocean environment. While the first applications of ocean acoustics began in the military, applications today encompass offshore energy production, national security, environmental monitoring, climate science, exploration and mapping, as well as fundamental ocean science. Even as demand for ocean acoustics grows, workforce development is challenged by both the multidisciplinary nature of the field and its widely varying career paths. Ocean acoustics may be housed in a diversity of departments in higher education institutions, and career paths and trajectory of formal education can range from the vocational/associates' level through the doctorate level. This report examines the state of ocean acoustics education; assesses expected demand for acoustics expertise over the next decade; identifies competencies required across higher education and professional training programs; and presents strategies to raise the profile of careers in ocean acoustics. The report recommends a number of actions that federal agencies, industry, and academia can take to develop the expertise needed to meet current and future workforce demands.
Fundamentals of Ocean Acoustics
Author: L. Brekhovskikh
Publisher: Springer Science & Business Media
Published: 2013-03-14
Total Pages: 262
ISBN-13: 3662023423
DOWNLOAD EBOOKThe 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.
Management Plan for Ocean Environmental Acoustics Programs in Support of Mobile Sonar Technology Development
Author: Carey D. Smith
Publisher:
Published: 1975
Total Pages: 64
ISBN-13:
DOWNLOAD EBOOKThe role of the U.S. Navy as a credible world sea power is placing increasing demands on sonar systems development for ASW. The management of the Navy's Ocean Environmental Acoustic Program (EVA) is of great concern because of the critical nature of this support service to systems development. At present, sonar developers and operators do not have sufficient EVA data and models available for optimum systems design and use. The deficiency is primarily due to a technological gap between EVA program outputs and the system developers requirements. The most effective and efficient management and implementation of the EVA program is therefore required. A detailed plan for a program management structure in NAVSEA (Sonar Technology Division) is presented; it calls for the establishment of a technical group assigned the responsibility for developing and maintaining a working relationship between environmental acousticians and systems developers.
Fundamentals of Acoustical Oceanography
Author: Herman Medwin
Publisher: Academic Press
Published: 1997-11-05
Total Pages: 739
ISBN-13: 0080532160
DOWNLOAD EBOOKThe 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
Report of a Survey of US Academic Programs in Ocean and Underwater Acoustics
Author: K. W. Lackie
Publisher:
Published: 1997
Total Pages:
ISBN-13:
DOWNLOAD EBOOKUnderwater acoustics remains the principal means to detect and locate submarines and other underwater objects. For this reason, the Office of Naval Research has sponsored a vigorous research program in underwater acoustics and related fields at both academic institutions and Navy in house organizations for many years. Unfortunately, no other Federal Government funding agency sponsors research in this area, and as a result the health, strength, and growth of the field in the US depends entirely on the ONR program. Interviews of senior U.S. acoustician and visits to a number of major institutions indicate that recent reductions in Naval research budgets have caused a significant decline in the vitality of the ocean acoustics research community in the U.S., especially in its capability to train graduate students in at sea experimental techniques and maintain its sea going infrastructure. Although a number of initiatives are identified that would improve the situation, only an increase in financial support will completely solve the problem. The current level of Federal funding is inadequate to support long-term Navy requirements for acoustician, though it may be adequate for the current environment of reduced budgets and priorities. The strength of this field, virtually the only one entrusted entirely to ONR's care, is not being sustained.
Computational Ocean Acoustics
Author: Finn B. Jensen
Publisher: Springer Science & Business Media
Published: 2011-06-10
Total Pages: 808
ISBN-13: 1441986782
DOWNLOAD EBOOKSenior level/graduate level text/reference presenting state-of-the- art numerical techniques to solve the wave equation in heterogeneous fluid-solid media. Numerical models have become standard research tools in acoustic laboratories, and thus computational acoustics is becoming an increasingly important branch of ocean acoustic science. The first edition of this successful book, written by the recognized leaders of the field, was the first to present a comprehensive and modern introduction to computational ocean acoustics accessible to students. This revision, with 100 additional pages, completely updates the material in the first edition and includes new models based on current research. It includes problems and solutions in every chapter, making the book more useful in teaching (the first edition had a separate solutions manual). The book is intended for graduate and advanced undergraduate students of acoustics, geology and geophysics, applied mathematics, ocean engineering or as a reference in computational methods courses, as well as professionals in these fields, particularly those working in government (especially Navy) and industry labs engaged in the development or use of propagating models.
