Download or read book Improving an Empirical Formula for the Absorption of Sound in the Sea written by C.A.M. van Moll and published by . This book was released on 2008 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Sound Absorption in Sea Water Low Frequency Relaxation Mechanism written by Robert H. Mellen and published by . This book was released on 1983 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: Resonator measurements measurements indicate that the principal B(OH)-3 absorption mechanism in sea water is an exchange between the B(OH)3/B(OH)-4 and HCO-3/CO3-2 equilibria in which coupling to the Ca2+ ion-pairing equilibria provides most of the molal volume change. If either Ca or CO2 are omitted, B(OH)3 absorption is an order of magnitude too low. T-jump measurements indicate a two-step B(OH)3 ionization process in H2O. In sea water, both relaxations occur and are coupled. Present theory shows that pH and absorption may have different relaxation frequencies as experimental data indicates. The empirical pH-dependent absorption formula derived from ocean measurements gives predictions that are consistent with the exchange relaxation model.
Download or read book Underwater Acoustic Modeling and Simulation written by Paul C. Etter and published by CRC Press. This book was released on 2017-12-19 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Global Model for Sound Absorption in Sea Water written by R. H. Mellen and published by . This book was released on 1987 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Attenuation of Low Frequency Sound in the Sea written by and published by . This book was released on 1980 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sound Propagation in the Sea written by Robert J. Urick and published by . This book was released on 1979 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics of Sound in the Sea written by Research Analysis Group and published by . This book was released on 1969 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling of Sound Propagation in the Sea written by Aleksandr Nikolaevich Barkhatov and published by Springer. This book was released on 1971 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is concerned with the application of modeling techniques and procedures to the investigation of sound propagation in the sea. The modeling method affords a means for studying the laws governing the sound fields in the sea and in other, similar media under controlled laboratory conditions and can be used in underwater acoustics as a coroHary to field experiments. The method has a number of advantages, principal of which are the relative simplicity and low cost of model tests by com parison with fuH-scale tests under oceanic conditions, the high accuracy of acoustical mea surements, excellent reproducibility of the measurement results, and the capability of rapidly varying the experimental conditions, which, unlike the conditions of field experiments, are under complete control. For the modeling of sound propagation in the sea the latter is treated, depending on the problem to be solved, either as a volume-homogeneous medium or as a medium possessing regular and randomly-distributed inhomogeneities. We direct our primary attention in the book to the modeling of layered-inhomogeneous media, but we also discuss separate problems bearing on the study of sound propagation in the sea. It is demonstrated in examples how modeling is employed to investigate the sound field in the ocean for certain typical vertical distributions of the velocity of sound in the ocean.
Download or read book A Treatise on Acoustic Radiation written by Sam Hanish and published by . This book was released on 1984 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Digital Underwater Acoustic Communications written by Lufen Xu and published by Academic Press. This book was released on 2016-09-16 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital Underwater Acoustic Communications focuses on describing the differences between underwater acoustic communication channels and radio channels, discusses loss of transmitted sound in underwater acoustic channels, describes digital underwater acoustic communication signal processing, and provides a comprehensive reference to digital underwater acoustic communication equipment. This book is designed to serve as a reference for postgraduate students and practicing engineers involved in the design and analysis of underwater acoustic communications systems as well as for engineers involved in underwater acoustic engineering. - Introduces the basics of underwater acoustics, along with the advanced functionalities needed to achieve reliable communications in underwater environment - Identifies challenges in underwater acoustic channels relative to radio channels, underwater acoustic propagation, and solutions - Shows how multi-path structures can be thought of as time diversity signals - Presents a new, robust signal processing system, and an advanced FH-SS system for multimedia underwater acoustic communications with moderate communication ranges (above 20km) and rates (above 600bps) - Describes the APNFM system for underwater acoustic communication equipment (including both civil and military applications), to be employed in active sonar to improve its performance
Download or read book Investigation of the 1 KHz Sound Absorption in Sea Water written by Vernon Pitkin Simmons and published by . This book was released on 1975 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sound Images of the Ocean written by Peter Wille and published by Springer Science & Business Media. This book was released on 2005-06-14 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sound Images of the Ocean is the first comprehensive overview of acoustic imaging applications in the various fields of marine research, utilization, surveillance, and protection. The book employs 400 sound images of the sea floor and of processes in the sea volume, contributed by more than 120 marine experts from 22 nations.
Download or read book Scientific and Engineering Studies written by Naval Underwater Systems Center (U.S.) and published by . This book was released on 1975 with total page 838 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low Frequency Sound Absorption in Sea Water A New Chemical Relaxation Mechanism written by D. G. Browning and published by . This book was released on 1981 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presented the oral and visual presentation entitled 'Low Frequency Sound Absorption in Sea Water: A New Chemical Relaxation Mechanism?, ' presented at the 101st Meeting of the Acoustical Society of America, 18-22 May 1981, in Ottawa, Ontario, Canada. Excess sound absorption in sea water arises mainly from chemical relaxations involving MgS04 and B(OH)3. The high-frequency (100 kHz) MgS04 relaxation has been identified as a multistep ion-pair process. The low frequency (1 kHz) and B(OH)3 relaxation apparently involves more complex interactions with other constituents. To investigate B(OH)3 interactions in a simpler system, we measured absorption in NH3 solution using the resonator method. We have found alpha max to be proportional to the product of NH(+) and B(OH)4( - ) concentrations; however, the magnitude is much too large to be caused by the ion pair. The mechanism, probably similar to that in sea water, resembles catalysis, the absorption being governed by the large volume change of the faster NH3/NH4(+) equilibrium and the relaxation frequency by the slower B(OH)3/B(OH)4( - ) equilibrium. (Author).
Download or read book A Review of Some Physical and Chemical Factors Affecting the Attenuation of Low Frequency Sound in Seawater written by Daniel J. Whelan and published by . This book was released on 1980 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: An attempt has been made to trace the contributions of various physical and chemical factors which effect the low frequency attenuation of sound observed in deep ocean channels and to establish that chemical relaxational processes do in fact contribute to the overall attenuation of this sound. The available evidence indicates that below 0.5 kHz, attenuation is affected predominantly by diffraction and diffusive scattering, but in the range 0.5 to 2.5 kHz, it is the effects of chemical relaxation processes, involving boric acid/borate and magnesium/carbonate equilibria, which dominate the sound absorption phenomenon.
Download or read book A Survey Report on Basic Problems of Underwater Acoustics Research written by National Research Council (U.S.). Committee on Undersea Warfare and published by . This book was released on 1950 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Underwater Acoustic Modelling and Simulation Third Edition written by P.C. Etter and published by CRC Press. This book was released on 2003-12-08 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
