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Littérature scientifique sur le sujet « Physical acoustics, underwater and ultrasonic »

Auteur : Grafiati

Publié le 1 février 2025

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Articles de revues sur le sujet "Physical acoustics, underwater and ultrasonic"

Godin, Oleg A., et Kay L. Gemba. « Graduate programs in physical, engineering, and underwater acoustics at the Naval Postgraduate School ». Journal of the Acoustical Society of America 152, n^o 4 (octobre 2022) : A122. http://dx.doi.org/10.1121/10.0015752.

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The Departments of Physics and of Electrical and Computer Engineering at the Naval Postgraduate School offer graduate programs in acoustics leading to MS and PhD degrees in applied physics and engineering acoustics. Engineering acoustics degrees can be completed in either traditional or distance learning modes. The departments also offer stand-alone academic certificate programs in fundamentals of engineering acoustics, underwater acoustics, and sonar system applications, with a set of three certificates leading to a MS degree in engineering acoustics. MS and PhD programs are interdisciplinary, with courses and laboratory work drawn principally from the fields of physics and electrical engineering. Subjects covered include waves and oscillations; fundamentals of physical and structural acoustics; the generation, propagation, and reception of sound in the ocean; civilian and military applications of sonar systems; and acoustic signal processing. Topics of recent theses and dissertations include development and field testing of novel sensors for atmospheric and ocean acoustics, modeling and measurements of ambient noise and sound propagation in the ocean, sound scattering in underwater waveguides, acoustic vector sensors and vector field properties, acoustic communications, noise interferometry, time reversal in acoustics, geo-acoustic inversion, acoustic remote sensing of the ocean, and acoustics of autonomous underwater and aerial vehicles.

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Lynch, James F., et Charles C. Church. « Introduction to the Special Issue on COVID-19 ». Journal of the Acoustical Society of America 153, n^o 1 (janvier 2023) : 573–75. http://dx.doi.org/10.1121/10.0017033.

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The COVID-19 pandemic has been a global event affecting all aspects of human life and society, including acoustic aspects. In this Special Issue on COVID-19 and acoustics, we present 48 papers discussing the acoustical impacts of the pandemic and how we deal with it. The papers are divided into seven categories which include: physical masking and speech production, speech perception, noise, the underwater soundscape, the urban soundscape, pathogen transmissibility, and medical diagnosis.

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Kuyama, Tamio. « New Research Fields of Ultrasonic Electronics and Underwater Acoustics ». Japanese Journal of Applied Physics 29, S1 (1 janvier 1990) : 8. http://dx.doi.org/10.7567/jjaps.29s1.8.

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Mallik, Wrik, Rajeev K. Jaiman et Jasmin Jelovica. « Predicting transmission loss in underwater acoustics using convolutional recurrent autoencoder network ». Journal of the Acoustical Society of America 152, n^o 3 (septembre 2022) : 1627–38. http://dx.doi.org/10.1121/10.0013894.

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Underwater noise transmission in the ocean environment is a complex physical phenomenon involving not only widely varying physical parameters and dynamical scales but also uncertainties in the ocean parameters. It is challenging to construct generalized physical models that can predict transmission loss in a broad range of situations. In this regard, we propose a convolutional recurrent autoencoder network (CRAN) architecture, which is a data-driven deep learning model for learning far-field acoustic propagation. Being data-driven, the CRAN model relies only on the quality of the data and is agnostic to how the data are obtained. The CRAN model can learn a reduced-dimensional representation of physical data and can predict the far-field acoustic signal transmission loss distribution in the ocean environment. We demonstrate the ability of the CRAN model to learn far-field transmission loss distribution in a two-dimensional ocean domain with depth-dependent sources. Results show that the CRAN can learn the essential physical elements of acoustic signal transmission loss generated due to geometric spreading, refraction, and reflection from the ocean surface and bottom. Such ability of the CRAN to learn complex ocean acoustics transmission has the potential for real-time far-field underwater noise prediction for marine vessel decision-making and online control.

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Ballard, Megan, Michael R. Haberman, Neal A. Hall, Mark F. Hamilton, Tyrone M. Porter et Preston S. Wilson. « Graduate acoustics education in the Cockrell School of Engineering at The University of Texas at Austin ». Journal of the Acoustical Society of America 152, n^o 4 (octobre 2022) : A124. http://dx.doi.org/10.1121/10.0015759.

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While graduate study in acoustics takes place in several colleges and schools at The University of Texas at Austin (UT Austin), including Communication, Fine Arts, Geosciences, and Natural Sciences, this poster focuses on the acoustics program in Engineering. The core of this program resides in the Departments of Mechanical Engineering (ME) and Electrical and Computer Engineering (ECE). Acoustics faculty in each department supervise graduate students in both departments. One undergraduate and nine graduate acoustics courses are taught in ME and ECE. Instructors for these courses include staff at Applied Research Laboratories at UT Austin, where many of the graduate students have research assistantships. The undergraduate course, taught every fall, begins with basic physical acoustics and proceeds to draw examples from different areas of engineering acoustics. Three of the graduate courses are taught every year: a two course sequence on physical acoustics, and a transducers course. The remaining six graduate acoustics courses, taught in alternate years, are on nonlinear acoustics, underwater acoustics, ultrasonics, architectural acoustics, wave phenomena, and acoustic metamaterials. An acoustics seminar is held most Fridays during the long semesters, averaging over ten per semester since 1984. The ME and ECE departments both offer Ph.D. qualifying exams in acoustics.

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Kukshtel, Natalie, Ying-Tsong Lin et Glen Gawarkiewicz. « Localization of an acoustic autonomous underwater vehicle using multi-channel back-propagation methods ». Journal of the Acoustical Society of America 153, n^o 3_supplement (1 mars 2023) : A302. http://dx.doi.org/10.1121/10.0018933.

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Autonomous underwater vehicles (AUVs) are extremely useful tools for studying the acoustics of complex ocean environments due to their ability to detect environmental changes with greater spatial resolution than fixed moorings. During the New England Shelf Break Acoustics (NESBA) experiments in May 2021, an AUV system was deployed to collect acoustic data for investigating the local biological, physical, and geological oceanography. This acoustic AUV system was comprised of a modified REMUS 600 vehicle, a hull-mounted 3.5 kHz transducer, and a towed multi-channel hydrophone array. Along mission profiles where the AUV is fully submerged but too shallow for bottom-lock navigation, one challenge is accurate localization of the AUV. Localization was performed in post-processing using multi-channel back-propagation methods applied to AUV source signals received at mooring hydrophones in the NESBA network as well as ship-towed sound source signals received at the AUV-towed array. Uncertainty in the localization estimates due to spatiotemporal sound speed changes was investigated, and hydrophone mooring tilt angle was determined by minimizing the localization uncertainty. Following localization, this AUV acoustic data was used to investigate local seafloor sub-bottom properties and the acoustic effects of biological scattering layers and varying physical oceanography. [Work supported by the Office of Naval Research.]

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Kelly, Mark, et Chengzhi Shi. « Ray tracing of long-range underwater acoustic vortex wave propagation ». Journal of the Acoustical Society of America 153, n^o 3_supplement (1 mars 2023) : A219. http://dx.doi.org/10.1121/10.0018712.

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The underwater acoustic communications environment is severely band-limited, which leads to a bottleneck in data transfer. Existing methods of data transfer in underwater acoustic communications applications typically rely primarily on conventional temporal and frequency modulation techniques and achieve bit rates peaking at approximately 40 kb/s. One method of easing the bottleneck and increasing the data rate is to explore further potential degrees of freedom which may be utilized. Acoustic orbital angular momentum (OAM) is a physical quantity that characterizes the rotation in a propagating helical pressure wavefront. The unique phase patterns of OAM carrying vortex waves form an orthogonal basis which may be useful as an additional degree of freedom in acoustics communications applications; however, the long-distance propagation of these waves is largely unstudied. By employing BELLHOP’s ray tracing algorithm, the dominant features of a propagating OAM carrying vortex wave are tracked over long ranges (to and beyond 1 km) under various environmental conditions. This provides essential guidance in the design of the sending and receiving arrays of high-speed underwater communications systems, which rely on multiplexing acoustic OAMs.

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Becker, Kyle M., Robert H. Headrick et Thomas C. Weber. « “Mud acoustics” and the ocean acoustics program ». Journal of the Acoustical Society of America 152, n^o 4 (octobre 2022) : A100. http://dx.doi.org/10.1121/10.0015675.

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Shallow water acoustics is one of the major thrusts of the Office of Naval Research Ocean Acoustics Program and has been an important area of interest to Navy programs since at least the work of Pekeris, Ewing, and Worzel in the 1940’s. In the 1950’s and early 1960’s, there was a flurry of activity both in the US and UK focused on propagation within and reflection from the seabed and the acoustical characteristics marine sediments. This work formed the basis of a research program carried out by the applied ocean acoustics branch of the acoustics division at the Naval Research Laboratory in the 1970’s. In April 1991, with the Cold War coming to an end, and a shift in interest from blue water to the littorals, ONR sponsored a workshop on shallow water acoustics at the Woods Hole Oceanographic Institution. This meeting, including underwater acousticians, geologists, geophysicists, and physical oceanographers, largely set the stage for the next 30 years of shallow water acoustics research supported by ONR. Prominent efforts include the ONR Geoclutter Program and the Shallow Water 2006 experiments, both focused on regions dominated by sandy bottoms. This talk describes more recent efforts in regions characterized by muddy bottoms.

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Hsu, Jin-Chen, Herwandi Alwi, Chun-Hao Wei, Kai-Li Liao et Che-Ting Huang. « Reflections of High-Frequency Pulsed Ultrasound by Underwater Acoustic Metasurfaces Composed of Subwavelength Phase-Gradient Slits ». Crystals 13, n^o 5 (20 mai 2023) : 846. http://dx.doi.org/10.3390/cryst13050846.

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We numerically and experimentally investigated the behavior of high-frequency underwater ultrasounds reflected by gradient acoustic metasurfaces. Metasurfaces were fabricated with a periodic array of gradient slits along the surface of a steel specimen. The finite element method was adopted for the acoustics–structure interaction problem to design the metasurfaces and simulate the reflected fields of the incident ultrasound. Our metasurfaces yielded anomalous reflection, specular reflection, apparent negative reflection, and radiation of surface-bounded modes for ultrasonic waves impinging on the metasurfaces at different incident angles. The occurrence of these reflection behaviors could be explained by the generalized Snell’s law for a gradient metasurface with periodic supercells. We showed that at some incident angles, strong anomalous reflection could be generated, which could lead to strong retroreflection at specific incident angles. Furthermore, we characterized the time evolution of the reflections using pulsed ultrasound. The simulated transient process revealed the formation of propagating reflected ultrasound fields. The experimentally measured reflected ultrasound signals verified the distinct reflection behaviors of the metasurfaces; strong anomalous reflection steering the ultrasound pulse and causing retroreflection was observed. This study paves the way for designing underwater acoustic metasurfaces for ultrasound imaging and caustic engineering applications using pulsed ultrasound in the high-frequency regime.

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KWON, HYU-SANG, YOUNG-CHUL CHOI, JIN-HO PARK et DOO-BYUNG YOON. « AN ENHANCED REFLECTION REMOVAL TECHNIQUE AND ITS APPLICATIONS ». Modern Physics Letters B 22, n^o 11 (10 mai 2008) : 1153–58. http://dx.doi.org/10.1142/s0217984908015991.

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Electroacoustic transducers using piezoelectric materials are popular in various applications such as underwater acoustics, ultrasound, earthquakes and elastic wave propagations. Especially, they are widely used in non-destructive testing for ultrasonic or acoustic emission transducers. In general, they generate and receive waves through media to find meaningful targets or physical characteristics of materials. However, in most uses, the media are bounded with finite dimensions, therefore there are multiple transmitting paths reflected from the boundaries. Such reflections corrupt the principal path signal to be analyzed. To overcome this problem, gating technique to gate successively transmitting and receiving signals, in other words, tone-burst signal technique, is most representatively used. This basically isolates the direct signal before the arrival of reflected signals in the time domain, and therefore it is also described as time windowing or time-selective windowing techniques without loss of generality. These techniques have inherent overlap problems invoked by long pulse duration, especially slightly damped signals or low frequency waves. An enhancement technique of shortening the pulses by digital filtering is proposed and successively applied in practical uses. It can isolate the principal path signal from reflected signals. Thereafter the signal can be perfectly recovered after removing reflections.

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Thèses sur le sujet "Physical acoustics, underwater and ultrasonic"

Kourchi, Hasna. « Μétaréseaux pοur la réflexiοn et la transmissiοn anοrmales de frοnts d’οnde acοustique dans l’eau ». Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMLH36.

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Un métaréseau est un assemblage périodique de diffuseurs conçu pour réfléchir ou réfracter une onde vers une direction anormale, non prévue par les lois de Snell-Descartes. Dans ce travail, nous avons conçu, fabriqué et caractérisé expérimentalement de tels métaréseaux pour le contrôle des ondes ultrasonores dans l’eau, en utilisant des tubes et des cylindres en laiton ainsi que des supports plastiques imprimés en 3D. Ces métaréseaux permettent de rediriger un front d'onde incident vers une direction arbitraire souhaitée, avec une efficacité élevée (proche de 100 %), aussi bien en réflexion sur une surface (comme l’interface eau/air) qu'en transmission. L’approche théorique repose sur les principes de la diffraction de Bragg et sur les interactions constructives et destructives des ondes. Les résultats de cette thèse démontrent l'efficacité des métaréseaux à induire des phénomènes acoustiques tels que la rétro-réflexion et la réponse asymétrique, grâce à l’utilisation de structures résonantes et non résonantes, validées par des simulations par éléments finis et des expérimentations. Cette recherche ouvre de nouvelles perspectives pour la manipulation des ondes acoustiques sous-marines, avec des applications potentielles dans les domaines de la détection, de l'absorption et de la réflexion des ondes en milieu marin
A metagrating is a periodic assembly of scatterers designed to reflect or refract a wave toward an anomalous direction, not predicted by Snell's law. In this work, we designed, fabricated, and experimentally characterized such metagratings for the control of ultrasonic waves in water, using brass tubes and cylinders as well as 3D-printed plastic supports. These metagratings enable the redirection of an incident wavefront to an arbitrarily desired direction with high efficiency (close to 100%), both in reflection on a surface (e.g., the water/air interface) and in transmission. The theoretical approach is based on the principles of Bragg diffraction and constructive and destructive wave interactions. The results of this thesis demonstrate the efficiency of metagratings in inducing acoustic phenomena such as retroreflection and asymmetric wave response, achieved through the use of resonant and non-resonant structures, validated by finite element simulations and experiments. This research opens new perspectives for the manipulation of underwater acoustic waves, with potential applications in the fields of wave detection, absorption, and reflection in marine environments

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Woolfe, Katherine. « A scaled physical model for underwater sound radiation from a partially submerged cylindrical shell under impact ». Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44874.

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The motivation for this study is to create a scaled laboratory model of a steel construction pile being driven by an impact hammer, which can provide controlled data to aid understanding and development of a structural acoustics numerical model simulating full-scale impact pile driving. The scaled model is approximately thirty times shorter than a typical 30-meter long Cast-in-Shell-Steel (CISS) pile. The relationship between the impact force, structural vibrations, and radiated sound field is analyzed. The time-domain acoustic intensity in the radial direction is found to be predominately negative immediately following excitation by the impact force. Analysis of the radial intensity shows that during the hammer strike, there is a net flow of energy from the structure into the water; however, because the structure and water are acoustically coupled a significant portion of the energy immediately flows back into the cylinder following hammer impact. This fluid-structure interaction results in a highly damped acoustic pulse in the water that propagates to the far field. In addition, the frequency spectra of the impact force, model pile wall acceleration in the radial direction in air and water, and underwater acoustic pressure are analyzed to find transfer functions between these variables. The transfer function between impact force and sound pressure is of particular interest because it can be used to calculate the system response for any other applied hammer force. This transfer function analysis has potential applications in mitigating noise generated by impact pile driving.

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Anderson, Shaun David. « Space-time-frequency processing from the analysis of bistatic scattering for simple underwater targets ». Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45771.

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The development of low-frequency SONAR systems, using a network of autonomous systems in unmanned vehicles, provides a practical means for bistatic measurements (i.e. when the source and receiver are widely separated, thus allowing multiple viewpoints of a target). Furthermore, time-frequency analysis, in particular Wigner-Ville analysis, takes advantage of the evolution of the time dependent echo spectrum to differentiate a man-made target (e.g. an elastic spherical shell, or cylinder) from a natural one of the similar shape (e.g. a rock). Indeed, key energetic features of man-made objects can aid in identification and classification in the presence of clutter and noise. For example, in a fluid-loaded thin spherical shell, an energetic feature is the mid-frequency enhancement echoes (MFE) that result from antisymmetric Lamb waves propagating around the circumference of the shell, which have been shown to be an acoustic feature useful in this pursuit. This research investigates the enhancement and benefits of bistatic measurements using the Wigner-Ville analysis along with acoustic imaging methods. Additionally, the advantage of joint space-time-frequency coherent processing is investigated for optimal array processing to enhance the detection of non-stationary signals across an array. The proposed methodology is tested using both numerical simulations and experimental data for spherical shells and solid cylinders. This research was conducted as part of the Shallow Water Autonomous Mine Sensing Initiative (SWAMSI) sponsored by ONR.

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Svensson, Elin. « Physical modelling of acoustic shallow-water communication channels ». Doctoral thesis, Stockholm : Farkost och flyg, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4572.

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Real, Gaultier. « An ultrasonic testbench for reproducing the degradation of sonar performance in fluctuating ocean ». Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4753/document.

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Le milieu océanique est sujet à de nombreuses sources de fluctuations. Les plus importantes sont les ondes internes, très fréquentes et entrainant des fluctuations de la distribution spatiale du champ de célérité du son. En raison de la longue période de ces phénomènes comparée au temps de propagation des ondes acoustiques pour des applications sonar, le processus peut être considéré figé dans le temps pour chaque réalisation stochastique du milieu. Le développement de bancs d’essais permettant de reproduire les effets de la turbulence atmosphérique a permis des avancées considérables dans le domaine de l’optique adaptative. Nous voyons donc un fort intérêt dans la possibilité de reproduire les effets des ondes internes sur la propagation du son en environnement contrôlé. Un protocole expérimental dans une cuve d’eau est proposé: une onde ultrasonore est transmise à travers une lentille acoustique aléatoirement rugueuse, ce qui produit des distorsions du front d’onde reçu. Les fluctuations des signaux reçus sont contrôlées en modifiant les paramètres statistiques de rugosité de la lentille. Ces paramètres sont reliés à l’analyse dimensionnelle permettant de classifier les configurations étudiées selon des régimes de fluctuations et de prédire les moments statistiques du champ acoustique jusqu’à l’ordre quatre. Une excellente correspondance est observée entre notre protocole expérimental et des résultats théoriques et numériques.La dégradation des performances des techniques de détection classiques appliquées à nos données expérimentales souligne le besoin de techniques correctives. Un état de l’art des techniques existantes dans divers domaines est proposé
The ocean medium is subject to many sources of fluctuations. The most critical ones were found to be internal waves, occurring frequently and inducing fluctuations of the spatial distribution of the sound speed field. Because of the fairly long period of this phenomenon as compared to the propagation time of acoustic waves for sonar applications, the process can be considered frozen in time for each stochastic realization of the medium. The development of testbenches allowing to reproduce the effect of atmospheric turbulence on optic waves propagation under laboratory conditions lead to considerable advancements in the field of adaptive optics. We therefore see a vivid interest in being able to reproduce the effects of internal waves on sound propagation in controlled environments. An experimental protocol in a water tank is proposed: an ultrasonic wave is transmitted through a randomly rough acoustic lens, producing distortions of the received wavefront. The induced signal fluctuations are controlled by tuning the statistical parameters of the roughness of the lens. Especially, they are linked to dimensional parameters allowing to classify the configurations into regimes of fluctuations and to predict the statistical moment of the acoustic pressure up to the fourth order. A remarkable relevance of our experimental scheme is found when compared to theoretical and simulation results. The degradation of classical signal processing techniques when applied to our acquired data highlights the need for corrective detection techniques. A review of the existing techniques in other domains is proposed

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Van, Komen David Franklin. « Deep Learning to Predict Ocean Seabed Type and Source Parameters ». BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/9213.

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In the ocean, light from the surface dissipates quickly leaving sound the only way to see at a distance. Different sediment types on the ocean floor and water properties like salinity, temperature, and ocean depth all change how sound travels across long distances. Hard sediment types, such as sand and bedrock, are highly reflective while softer sediment types, such as mud, are more absorptive and change the received sound upon arrival. Unfortunately, the vast majority of the ocean floor is not mapped and the expenses involved in creating such a map are far too great. Traditional signal processing methods in underwater acoustics attempt to localize sources and estimate seabed properties, but require a priori decisions and fall victim to ill conditioning and non-linear relationships between the unknowns and are computationally expensive. To address these problems, a deep learning method is proposed to distinguish between seabed types while also predicting source parameters such as source-receiver range from simulated training data. In this thesis, several studies are presented that explore the effectiveness of convolutional neural networks to make predictions from two types of sounds that propagated through the ocean: impulsive explosions and ship noise. These studies show that time-series signals and spectrograms contain sufficient information for deep learning, and additional preprocessing for feature extraction is not necessary. Training data considerations, such as randomness in the network weights and inclusion of representative variability are also explored. In all, this study shows that deep learning is a useful tool in underwater acoustics and has significant potential for seabed parameter estimation.

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Campbell, Castillo Inez. « The effects of physical, biological and anthropogenic noise on the occurrence of dolphins in the Pacific region of the Panama Canal ». Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/4484.

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The main aim of this thesis was to investigate the occurrence of dolphins in Pacific waters adjacent to the Panama Canal in the context of biological, temporal and spatial factors. Acoustic data were collected at 101 sites at a range of distances and depths from the shipping region. Data were collected between March 2010 and April 2011 in a diurnal cycle over a total of 114 recording days. Received sound levels were split into 1/3 Octave bandwidths to study variation in sound pressure levels and then converted to spectrum density levels to show the sound components of the background noise in this region. Generalised Linear Models were used to relate dolphin whistle detections to temporal, spatial, environmental and acoustic variables. The major sources of background noise were biological noise from soniferous fish and snapping shrimp and anthropogenic noise from vessels characterised by mid to high frequencies produced by artisanal fishing boats. There was monthly and diurnal variation with some locations characterised by loud sounds in the mid to high frequencies at night. Whistle characteristics analysis revealed that the frequencies and range of the whistles were different to those previously reported under similar conditions. Whistles varied diurnally and in the presence of fish chorus and fishing boats. The study highlights a strong correlation between fish choruses and whistle detection. Temporal and spatial models showed that whistle detections varied monthly and in relation to fish noise and small vessel engine noise. Dolphins were distributed throughout most of the study area; however, whistle detections varied with distance from the coast. The results provide new knowledge about background noise composition in this region and provide the first information on the ecology of dolphin whistles in relation to this background noise, especially to fish chorus.

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Livres sur le sujet "Physical acoustics, underwater and ultrasonic"

R, Kerman B., et Conference on Natural Physical Sources of Underwater Sound (1990 : Cambridge, England), dir. Natural physical sources of underwater sound : Sea surface sound (2). Dordrecht : Kluwer Academic Publishers, 1993.

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Kerman, B. R. Natural physical sources of underwater sound : Sea surface sound (2). Dordrecht : Springer Science, 1993.

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Italy), International School of Physical Acoustics (4th 1991. Acoustic sensing and probing : Fourth course of the International School on Physical Acoustics, 3-10 October 1991, Erice, Italy. Singapore : World Scientific, 1992.

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W, Povey M. J., McClements D. J, Institute of Physics (Great Britain). Physical Acoustics Group. et Institute of Acoustics (Great Britain), dir. Developments in acoustics and ultrasonics : Proceedings of the meeting organised by the IOP Physical Acoustics Group, Leeds, UK, 24-25 September 1991. Bristol, UK : Institute of Physics Pub., 1992.

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Diachok, O. Full Field Inversion Methods in Ocean and Seismo-Acoustics. Dordrecht : Springer Netherlands, 1995.

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M, Langton C., Palmer S. B, Institute of Acoustics (Great Britain), Institute of Physics (Great Britain) et Physical Acoustics Group, dir. Ultrasonic studies of bone : Proceedings of a one day meeting of the Physical Acoustics Group of the Institute of Physics and the Institute of Acoustics, 20th May 1987. Bristol : Institute of Physics, 1987.

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D, Richardson M., dir. High-frequency seafloor acoustics. New York : Springer, 2007.

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Ambedkar, B. Ultrasonic Coal-Wash for De-Ashing and De-Sulfurization : Experimental Investigation and Mechanistic Modeling. Berlin, Heidelberg : Springer Berlin Heidelberg, 2012.

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1943-, Buckingham M. J., et Potter John, dir. Sea surface sound '94 : Proceedings of the III International Meeting on Natural Physical Processes Related to Sea Surface Sound, University of California, Lake Arrowhead, 7-11 March 1994. Singapore : World Scientific, 1995.

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Physical Acoustics : Underwater Scattering and Radiation (Physical Acoustics). Academic Pr, 1992.

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Chapitres de livres sur le sujet "Physical acoustics, underwater and ultrasonic"

Ueha, Sadayuki. « Recent Development of Ultrasonic Motors ». Dans Physical Acoustics, 189–96. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_17.

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Fay, B. « Ultrasonic Backscattering : Fundamentals and Applications ». Dans Physical Acoustics, 41–53. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_5.

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Reibold, R., et P. Kwiek. « Optical Nearfield of Ultrasonic Light Diffraction ». Dans Physical Acoustics, 129–42. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_12.

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Alippi, A., A. Bettucci et F. Craciun. « Ultrasonic Waves in Monodimensional Periodic Composites ». Dans Physical Acoustics, 13–19. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_2.

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Euvrard, D., et O. Mechiche Alami. « Underwater Sound Scattering by Surface Gravity Waves ». Dans Physical Acoustics, 313–18. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_36.

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Quentin, Gerard J. « Use of Short Pulses and Ultrasonic Spectroscopy in Scattering Studies ». Dans Physical Acoustics, 119–28. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_11.

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Singh, V. R., et Ravinder Agarwal. « Study of Inhomogeneous and Heterogeneous Ultrasonic Waves in Kidney Stones ». Dans Physical Acoustics, 621–23. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_83.

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Blomme, Erik, Rudy Briers et Oswald Leroy. « Analysis of the Nearfield of Laser Light Diffracted by a Plane Ultrasonic Wave ». Dans Physical Acoustics, 243–48. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_26.

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Sliwinski, Antoni. « Modulation Effects in Light Diffraction by Two Ultrasonic Beams and Application in Signal Processing ». Dans Physical Acoustics, 165–78. Boston, MA : Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-9573-1_15.

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Giurgiutiu, Victor, et Bin Lin. « Physical Basis for Ultrasonic Acoustics ». Dans Handbook of Advanced Non-Destructive Evaluation, 1–40. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-30050-4_57-1.

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Actes de conférences sur le sujet "Physical acoustics, underwater and ultrasonic"

Chen, Yunfei, Dapeng Yu, Bing Jia, Zhenshan Wang, Jintao Yong et Yanjie Wang. « Influence of Physical Parameters on Echo Spectrum of Underwater Target ». Dans 2024 OES China Ocean Acoustics (COA), 1–6. IEEE, 2024. http://dx.doi.org/10.1109/coa58979.2024.10723637.

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Capps, R. N. « The Role of Physical Acoustics in the Development of Specialty Polymers for Underwater Acoustical Applications ». Dans IEEE 1985 Ultrasonics Symposium. IEEE, 1985. http://dx.doi.org/10.1109/ultsym.1985.198692.

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Thakare, Dhawal R., Prabhu Rajagopal et Pierre Belanger. « Ultrasonic guided waves in bone system with degradation ». Dans 5th Pacific Rim Underwater Acoustics Conference. Acoustical Society of America, 2016. http://dx.doi.org/10.1121/2.0000147.

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Leighton, Timothy G. « The acoustic bubble : Oceanic bubble acoustics and ultrasonic cleaning ». Dans 5th Pacific Rim Underwater Acoustics Conference. Acoustical Society of America, 2015. http://dx.doi.org/10.1121/2.0000121.

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Norli, Petter, Emilie Vallée, Magne Aanes, Asbjørn Spilde, Henrik Duerud, Fabrice Prieur, Tore Bjåstad, Øyvind Standal et Martijn Frijlink. « Ultrasonic detection of stress corrosion cracks in gaseous atmosphere using Broadband transducers ». Dans International Conference on Underwater Acoustics. ASA, 2019. http://dx.doi.org/10.1121/2.0001334.

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Blanc, Silvia, Igor Prario, Mariano Cinquini, Patricio Bos et Analia Tolivia. « Ultrasonic scattering responses from phytoplankton : Measurements and modelling ». Dans 2017 IEEE/OES Acoustics in Underwater Geosciences Symposium (RIO Acoustics). IEEE, 2017. http://dx.doi.org/10.1109/rioacoustics.2017.8349702.

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BANGASH, MA, W. MOLKENSTRUCK, R. REIBOLD et RC CHIVERS. « A DETAILED COMPARISON OF ULTRASONIC FIELD MEASUREMENT TECHNIQUES ». Dans Autumn Conference 1995 - Physical Acoustics Symposium. Institute of Acoustics, 2024. http://dx.doi.org/10.25144/20121.

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HOPPER, C., S. ASSOUS, DA GUNN, PD JACKSON, JG REES, MA LOVELL et LM LINNETT. « BIOLOGICALLY-INSPIRED ULTRASONIC SIGNALS FOR PHYSICAL CHARACTERISATION OF GEOLOGICAL MATERIALS ». Dans Spring Conference Acoustics 2008. Institute of Acoustics, 2023. http://dx.doi.org/10.25144/17543.

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BLAKEY, JR, et RC CHIVERS. « THE EFFECTIVE RADIUS CONCEPT FOR PIEZOELECTRIC ULTRASONIC TRANSDUCERS AND ITS PHYSICAL INTERPRETATION ». Dans Acoustics '90. Institute of Acoustics, 2024. http://dx.doi.org/10.25144/21281.

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CHALLIS, RE, RJ FREEMANTLE et AK HOLMES. « ON ULTRASONIC COMPRESSION WAVE ABSORPTION IN UNFILLED AND FILLED POLYMERS ». Dans Autumn Conference 1995 - Physical Acoustics Symposium. Institute of Acoustics, 2024. http://dx.doi.org/10.25144/20122.

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