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Sample records for sonar sound beam

  1. Tongue-driven sonar beam steering by a lingual-echolocating fruit bat.

    Directory of Open Access Journals (Sweden)

    Wu-Jung Lee

    2017-12-01

    Full Text Available Animals enhance sensory acquisition from a specific direction by movements of head, ears, or eyes. As active sensing animals, echolocating bats also aim their directional sonar beam to selectively "illuminate" a confined volume of space, facilitating efficient information processing by reducing echo interference and clutter. Such sonar beam control is generally achieved by head movements or shape changes of the sound-emitting mouth or nose. However, lingual-echolocating Egyptian fruit bats, Rousettus aegyptiacus, which produce sound by clicking their tongue, can dramatically change beam direction at very short temporal intervals without visible morphological changes. The mechanism supporting this capability has remained a mystery. Here, we measured signals from free-flying Egyptian fruit bats and discovered a systematic angular sweep of beam focus across increasing frequency. This unusual signal structure has not been observed in other animals and cannot be explained by the conventional and widely-used "piston model" that describes the emission pattern of other bat species. Through modeling, we show that the observed beam features can be captured by an array of tongue-driven sound sources located along the side of the mouth, and that the sonar beam direction can be steered parsimoniously by inducing changes to the pattern of phase differences through moving tongue location. The effects are broadly similar to those found in a phased array-an engineering design widely found in human-made sonar systems that enables beam direction changes without changes in the physical transducer assembly. Our study reveals an intriguing parallel between biology and human engineering in solving problems in fundamentally similar ways.

  2. Echolocating bats emit a highly directional sonar sound beam in the field

    DEFF Research Database (Denmark)

    Surlykke, Annemarie; Boel Pedersen, Simon; Jakobsen, Lasse

    2009-01-01

    Bats use echolocation or biosonar to navigate and find prey at night. They emit short ultrasonic calls and listen for reflected echoes. The beam width of the calls is central to the function of the sonar, but directionality of echolocation calls has never been measured from bats flying in the wild....... We used a microphone array to record sounds and determine horizontal directionality for echolocation calls of the trawling Daubenton's bat, Myotis daubentonii, flying over a pond in its natural habitat. Myotis daubentonii emitted highly directional calls in the field. Directionality increased...... and directionality can be explained by the simple piston model. The model also suggests that the increase in the emitted intensity in the field is caused by the increased directionality, focusing sound energy in the forward direction. The bat may increase directionality by opening the mouth wider to emit a louder...

  3. IDENTIFIKASI PROFIL DASAR LAUT MENGGUNAKAN INSTRUMEN SIDE SCAN SONAR DENGAN METODE BEAM PATTERN DISCRETE-EQUI-SPACED UNSHADED LINE ARRAY

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-05-01

    which was a sea of Riau Island in Indonesia. Side scan sonar (SSS is an instrument based on sonar system wich capable of showing the image of two-dimensional surface of the seabed with contour conditions, topography, and the underwater target simultaneously. Beam Pattern Discrete-equispaced unshaded Line Array Method is used to compute the two-dimensional beam pattern which depends on the angle of the incoming sound waves from the axis of the array are acceptable depending on the angle at which the sound beam array. This research was conducted in December 2016 in the sea Punggur, Batam, Riau Islands-Indonesia, with coordinate system  104 ° 08,7102 E and 1° 03,2448 N until 1 ° 03.3977N and 104 ° 08,8133 E,  using Side Scan Sonar Tow C-Max CM2 fish instruments with a frequency of 325 kHz. The Results obtained from the recording there are 7 targets, and Beam pattern of Discrete-Beam method Equi-Spaced unshaded Line Array in targets 4 have the highest value in the Pattern is 21:08 dB directivity. The results of the model's beam pattern have anaxis value at the incidence angle (o of the directivity pattern (dB are not on the value 0 or the central beam pattern generated on the target 6 with incident angle -1.5 o and 1.5o have declined by -40 dB. Characteristics of bottom sediment in the sea waters Punggur found more sand.Discrete-method result Beam Equi-Spaced unshaded Line Array discovered the sunken wreck. Keywords: Side Scan Sonar, Beam Pattern Discrete-Equi-Spaced Unshaded Line Array, Incidence angle, Directivity pattern

  4. Sperm whales reduce foraging effort during exposure to 1-2 kHz sonar and killer whale sounds.

    Science.gov (United States)

    Isojunno, Saana; Cure, Charlotte; Kvadsheim, Petter Helgevold; Lam, Frans-Peter Alexander; Tyack, Peter Lloyd; Wensveen, Paul Jacobus; Miller, Patrick James O'Malley

    2016-01-01

    The time and energetic costs of behavioral responses to incidental and experimental sonar exposures, as well as control stimuli, were quantified using hidden state analysis of time series of acoustic and movement data recorded by tags (DTAG) attached to 12 sperm whales (Physeter macrocephalus) using suction cups. Behavioral state transition modeling showed that tagged whales switched to a non-foraging, non-resting state during both experimental transmissions of low-frequency active sonar from an approaching vessel (LFAS; 1-2 kHz, source level 214 dB re 1 µPa m, four tag records) and playbacks of potential predator (killer whale, Orcinus orca) sounds broadcast at naturally occurring sound levels as a positive control from a drifting boat (five tag records). Time spent in foraging states and the probability of prey capture attempts were reduced during these two types of exposures with little change in overall locomotion activity, suggesting an effect on energy intake with no immediate compensation. Whales switched to the active non-foraging state over received sound pressure levels of 131-165 dB re 1 µPa during LFAS exposure. In contrast, no changes in foraging behavior were detected in response to experimental negative controls (no-sonar ship approach or noise control playback) or to experimental medium-frequency active sonar exposures (MFAS; 6-7 kHz, source level 199 re 1 µPa m, received sound pressure level [SPL] = 73-158 dB re 1 µPa). Similarly, there was no reduction in foraging effort for three whales exposed to incidental, unidentified 4.7-5.1 kHz sonar signals received at lower levels (SPL = 89-133 dB re 1 µPa). These results demonstrate that similar to predation risk, exposure to sonar can affect functional behaviors, and indicate that increased perception of risk with higher source level or lower frequency may modulate how sperm whales respond to anthropogenic sound.

  5. Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

    DEFF Research Database (Denmark)

    Falk, Benjamin; Jakobsen, Lasse; Surlykke, Annemarie

    2014-01-01

    Echolocating bats use active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance and pursuit of prey. The sensing behavior of bats includes the planning of 3D spatial trajectory paths, which are guided by echo information....... The temporal patterning of sonar sound groups was related to path planning around obstacles in the forest. Together, these results contribute to our understanding of how bats coordinate echolocation and flight behavior to represent and navigate their environment........ In this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. Using high-speed video and audio recordings, we reconstructed and analyzed 3D flight trajectories, sonar beam aim...

  6. Sonar sound groups and increased terminal buzz duration reflect task complexity in hunting bats

    DEFF Research Database (Denmark)

    Hulgard, K.; Ratcliffe, J. M.

    2016-01-01

    to prey under presumably more difficult conditions. Specifically, we found Daubenton's bats, Myotis daubentonii, produced longer buzzes when aerial-hawking versus water-trawling prey, but that bats taking revolving air- and water-borne prey produced more sonar sound groups than did the bats when taking...

  7. Evaluation of a Single-Beam Sonar System to Map Seagrass at Two Sites in Northern Puget Sound, Washington

    Science.gov (United States)

    Stevens, Andrew W.; Lacy, Jessica R.; Finlayson, David P.; Gelfenbaum, Guy

    2008-01-01

    Seagrass at two sites in northern Puget Sound, Possession Point and nearby Browns Bay, was mapped using both a single-beam sonar and underwater video camera. The acoustic and underwater video data were compared to evaluate the accuracy of acoustic estimates of seagrass cover. The accuracy of the acoustic method was calculated for three classifications of seagrass observed in underwater video: bare (no seagrass), patchy seagrass, and continuous seagrass. Acoustic and underwater video methods agreed in 92 percent and 74 percent of observations made in bare and continuous areas, respectively. However, in patchy seagrass, the agreement between acoustic and underwater video was poor (43 percent). The poor agreement between the two methods in areas with patchy seagrass is likely because the two instruments were not precisely colocated. The distribution of seagrass at the two sites differed both in overall percent vegetated and in the distribution of percent cover versus depth. On the basis of acoustic data, seagrass inhabited 0.29 km2 (19 percent of total area) at Possession Point and 0.043 km2 (5 percent of total area) at the Browns Bay study site. The depth distribution at the two sites was markedly different. Whereas the majority of seagrass at Possession Point occurred between -0.5 and -1.5 m MLLW, most seagrass at Browns Bay occurred at a greater depth, between -2.25 and -3.5 m MLLW. Further investigation of the anthropogenic and natural factors causing these differences in distribution is needed.

  8. Problems in nonlinear acoustics: Scattering of sound by sound, parametric receiving arrays, nonlinear effects in asymmetric sound beams and pulsed finite amplitude sound beams

    Science.gov (United States)

    Hamilton, Mark F.

    1989-08-01

    Four projects are discussed in this annual summary report, all of which involve basic research in nonlinear acoustics: Scattering of Sound by Sound, a theoretical study of two nonconlinear Gaussian beams which interact to produce sum and difference frequency sound; Parametric Receiving Arrays, a theoretical study of parametric reception in a reverberant environment; Nonlinear Effects in Asymmetric Sound Beams, a numerical study of two dimensional finite amplitude sound fields; and Pulsed Finite Amplitude Sound Beams, a numerical time domain solution of the KZK equation.

  9. On doing two things at once: dolphin brain and nose coordinate sonar clicks, buzzes and emotional squeals with social sounds during fish capture.

    Science.gov (United States)

    Ridgway, Sam; Samuelson Dibble, Dianna; Van Alstyne, Kaitlin; Price, DruAnn

    2015-12-01

    Dolphins fishing alone in open waters may whistle without interrupting their sonar clicks as they find and eat or reject fish. Our study is the first to match sound and video from the dolphin with sound and video from near the fish. During search and capture of fish, free-swimming dolphins carried cameras to record video and sound. A hydrophone in the far field near the fish also recorded sound. From these two perspectives, we studied the time course of dolphin sound production during fish capture. Our observations identify the instant of fish capture. There are three consistent acoustic phases: sonar clicks locate the fish; about 0.4 s before capture, the dolphin clicks become more rapid to form a second phase, the terminal buzz; at or just before capture, the buzz turns to an emotional squeal (the victory squeal), which may last 0.2 to 20 s after capture. The squeals are pulse bursts that vary in duration, peak frequency and amplitude. The victory squeal may be a reflection of emotion triggered by brain dopamine release. It may also affect prey to ease capture and/or it may be a way to communicate the presence of food to other dolphins. Dolphins also use whistles as communication or social sounds. Whistling during sonar clicking suggests that dolphins may be adept at doing two things at once. We know that dolphin brain hemispheres may sleep independently. Our results suggest that the two dolphin brain hemispheres may also act independently in communication. © 2015. Published by The Company of Biologists Ltd.

  10. Review: Marine Seismic And Side-Scan Sonar Investigations For Seabed Identification With Sonar System

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-06-01

    Full Text Available Marine seismic reflection data have been collected for decades and since the mid-to late- 1980s much of this data is positioned relatively accurately. Marine geophysical acquisition of data is a very expensive process with the rates regularly ship through dozens of thousands of euros per day. Acquisition of seismic profiles has the position is determined by a DGPS system and navigation is performed by Hypack and Maxview software that also gives all the offsets for the equipment employed in the survey. Examples of some projects will be described in terms of the project goals and the geophysical equipment selected for each survey and specific geophysical systems according to with the scope of work. For amplitude side scan sonar image, and in the multi-frequency system, color, becoming a significant properties of the sea floor, the effect of which is a bully needs to be fixed. The main confounding effect is due to absorption of water; geometric spread; shape beam sonar function (combined transmit-receive sonar beam intensity as a function of tilt angle obtained in this sonar reference frame; sonar vehicle roll; form and function of the seabed backscatter (proportion incident on the seabed backscattered signal to sonar as a function of the angle of incidence relative to the sea floor; and the slope of the seabed. The different angles of view are generated by the translation of the sonar, because of the discrete steps involved by the sequential pings, the angular sampling of the bottom.

  11. Colour Sonar: Multi-Frequency Sidescan Sonar Images of the Seabed in the Inner Sound of the Pentland Firth, Scotland

    Directory of Open Access Journals (Sweden)

    Duncan Tamsett

    2016-03-01

    Full Text Available The backscatter response of a seabed to an incident sonar signal is dependent on the carrier wave frequency: i.e., the seabed is acoustically colourful. Colour is implemented in a prototype three-frequency sidescan sonar system deployed in the Pentland Firth, north Scotland. Sonar amplitude data as a function of frequency are processed to render them an unconfounded effect of the seabed normalized to the response at a reference inclination angle, for colour to be a meaningful property of the seabed. Methods for mapping data at sonar frequencies to optical primary colours for human visualisation are explored. We recommend methods that in our opinion generate colour characteristics harmonious with human vision in which: shadow is white; saturation black; colour shade darkness is proportional to backscatter strength; and shades of red, green and blue are seen in proportion to the backscatter amplitudes of the low-, mid- and high-frequency sonar data. Frequency equalisation is applied to achieve a balance in colour responses in images. The seabed in the survey area is acoustically colourful. Using the “negative BGR” colour mapping method: a weakly backscattering sand dune in the north of the survey area appears as shades of light blue and purple; a strongly backscattering halo of cobbles around the dune appears as shades of hazel brown; a strongly backscattering gravel ridge across the south of the survey area appears as shades of royal blue; and exposed rock as textures ranging in colour from light brown to light blue/green. There is evidence for colour anisotropy (a dependence of colour on the direction of ensonification. Similarities between anthropic colour sonar and the natural sonar of Microchiropteran bats are noted. Bats’ sonar satisfies the information criteria for acoustic colour, and it is hypothesized that it informs a colourfully-perceived world view.

  12. Combining split-beam and dual-frequency identification sonars to estimate abundance of anadromous fishes in the Roanoke River, North Carolina

    Science.gov (United States)

    Hughes, Jacob B.; Hightower, Joseph E.

    2015-01-01

    Riverine hydroacoustic techniques are an effective method for evaluating abundance of upstream migrating anadromous fishes. To use these methods in the Roanoke River, North Carolina, at a wide site with uneven bottom topography, we used a combination of split-beam sonar and dual-frequency identification sonar (DIDSON) deployments. We aimed a split-beam sonar horizontally to monitor midchannel and near-bottom zones continuously over the 3-month spring monitoring periods in 2010 and 2011. The DIDSON was rotated between seven cross-channel locations (using a vertical aim) and nearshore regions (using horizontal aims). Vertical deployment addressed blind spots in split-beam coverage along the bottom and provided reliable information about the cross-channel and vertical distributions of upstream migrants. Using a Bayesian framework, we modeled sonar counts within four cross-channel strata and apportioned counts by species using species proportions from boat electrofishing and gill netting. Modeled estimates (95% credible intervals [CIs]) of total upstream migrants in 2010 and 2011 were 2.5 million (95% CI, 2.4–2.6 million) and 3.6 million (95% CI, 3.4–3.9 million), respectively. Results indicated that upstream migrants are extremely shore- and bottom-oriented, suggesting nearshore DIDSON monitoring improved the accuracy and precision of our estimates. This monitoring protocol and model may be widely applicable to river systems regardless of their cross-sectional width or profile.

  13. Passive Sonar Target Detection Using Statistical Classifier and Adaptive Threshold

    Directory of Open Access Journals (Sweden)

    Hamed Komari Alaie

    2018-01-01

    Full Text Available This paper presents the results of an experimental investigation about target detecting with passive sonar in Persian Gulf. Detecting propagated sounds in the water is one of the basic challenges of the researchers in sonar field. This challenge will be complex in shallow water (like Persian Gulf and noise less vessels. Generally, in passive sonar, the targets are detected by sonar equation (with constant threshold that increases the detection error in shallow water. The purpose of this study is proposed a new method for detecting targets in passive sonars using adaptive threshold. In this method, target signal (sound is processed in time and frequency domain. For classifying, Bayesian classification is used and posterior distribution is estimated by Maximum Likelihood Estimation algorithm. Finally, target was detected by combining the detection points in both domains using Least Mean Square (LMS adaptive filter. Results of this paper has showed that the proposed method has improved true detection rate by about 24% when compared other the best detection method.

  14. Sound Beams with Shockwave Pulses

    Science.gov (United States)

    Enflo, B. O.

    2000-11-01

    The beam equation for a sound beam in a diffusive medium, called the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, has a class of solutions, which are power series in the transverse variable with the terms given by a solution of a generalized Burgers’ equation. A free parameter in this generalized Burgers’ equation can be chosen so that the equation describes an N-wave which does not decay. If the beam source has the form of a spherical cap, then a beam with a preserved shock can be prepared. This is done by satisfying an inequality containing the spherical radius, the N-wave pulse duration, the N-wave pulse amplitude, and the sound velocity in the fluid.

  15. Real-Time 3D Sonar Modeling And Visualization

    Science.gov (United States)

    1998-06-01

    looking back towards Manta sonar beam, Manta plus sonar from 1000m off track. 185 NUWC sponsor Erik Chaum Principal investigator Don Brutzman...USN Sonar Officer LT Kevin Byrne USN Intelligence Officer CPT Russell Storms USA Erik Chaum works in NUWC Code 22. He supervised the design and...McGhee, Bob, "The Phoenix Autonomous Underwater Vehicle," chapter 13, AI-BasedMobile Robots, editors David Kortenkamp, Pete Bonasso and Robin Murphy

  16. Cost-Effective Mapping of Benthic Habitats in Inland Reservoirs through Split-Beam Sonar, Indicator Kriging, and Historical Geologic Data

    Energy Technology Data Exchange (ETDEWEB)

    Venteris, Erik R.; May, Cassandra

    2014-04-23

    Because bottom substrate composition is an important control on the temporal and spatial location of the aquatic community, accurate maps of benthic habitats of inland lakes and reservoirs provide valuable information to managers, recreational users, and scientists. Therefore, we collected vertical, split-beam sonar data (roughness [E1], hardness [E2], and bathymetry) and sediment samples to make such maps. Statistical calibration between sonar parameters and sediment classes was problematic because the E1:E2 ratios for soft (muck and clay) sediments overlapped a lower and narrower range for hard (gravel) substrates. Thus, we used indicator kriging (IK) to map the probability that unsampled locations did not contain coarse sediments. To overcome the calibration issue we tested proxies for the natural processes and anthropogenic history of the reservoir as potential predictive variables. Of these, a geologic map proved to be the most useful. The central alluvial valley and mudflats contained mainly muck and organic-rich clays. The surrounding glacial till and shale bedrock uplands contained mainly poorly sorted gravels. Anomalies in the sonar data suggested that the organic-rich sediments also contained trapped gases, presenting additional interpretive issues for the mapping. We extended the capability of inexpensive split-beam sonar units through the incorporation of historic geologic maps and other records as well as validation with dredge samples. Through the integration of information from multiple data sets, were able to objectively identify bottom substrate and provide reservoir users with an accurate map of available benthic habitat.

  17. Cost-effective mapping of benthic habitats in inland reservoirs through split-beam sonar, indicator kriging, and historical geologic data.

    Directory of Open Access Journals (Sweden)

    Erik R Venteris

    Full Text Available Because bottom substrate composition is an important control on the temporal and spatial location of the aquatic community, accurate maps of benthic habitats of inland lakes and reservoirs provide valuable information to managers, recreational users, and scientists. Therefore, we collected vertical, split-beam sonar data (roughness [E1], hardness [E2], and bathymetry and sediment samples to make such maps. Statistical calibration between sonar parameters and sediment classes was problematic because the E1:E2 ratios for soft (muck and clay sediments overlapped a lower and narrower range for hard (gravel substrates. Thus, we used indicator kriging (IK to map the probability that unsampled locations did not contain coarse sediments. To overcome the calibration issue we tested proxies for the natural processes and anthropogenic history of the reservoir as potential predictive variables. Of these, a geologic map proved to be the most useful. The central alluvial valley and mudflats contained mainly muck and organic-rich clays. The surrounding glacial till and shale bedrock uplands contained mainly poorly sorted gravels. Anomalies in the sonar data suggested that the organic-rich sediments also contained trapped gases, presenting additional interpretive issues for the mapping. We extended the capability of inexpensive split-beam sonar units through the incorporation of historic geologic maps and other records as well as validation with dredge samples. Through the integration of information from multiple data sets, were able to objectively identify bottom substrate and provide reservoir users with an accurate map of available benthic habitat.

  18. Problems in nonlinear acoustics: Pulsed finite amplitude sound beams, nonlinear acoustic wave propagation in a liquid layer, nonlinear effects in asymmetric cylindrical sound beams, effects of absorption on the interaction of sound beams, and parametric receiving arrays

    Science.gov (United States)

    Hamilton, Mark F.

    1990-12-01

    This report discusses five projects all of which involve basic theoretical research in nonlinear acoustics: (1) pulsed finite amplitude sound beams are studied with a recently developed time domain computer algorithm that solves the KZK nonlinear parabolic wave equation; (2) nonlinear acoustic wave propagation in a liquid layer is a study of harmonic generation and acoustic soliton information in a liquid between a rigid and a free surface; (3) nonlinear effects in asymmetric cylindrical sound beams is a study of source asymmetries and scattering of sound by sound at high intensity; (4) effects of absorption on the interaction of sound beams is a completed study of the role of absorption in second harmonic generation and scattering of sound by sound; and (5) parametric receiving arrays is a completed study of parametric reception in a reverberant environment.

  19. A risk function for behavioral disruption of Blainville's beaked whales (Mesoplodon densirostris from mid-frequency active sonar.

    Directory of Open Access Journals (Sweden)

    David Moretti

    Full Text Available There is increasing concern about the potential effects of noise pollution on marine life in the world's oceans. For marine mammals, anthropogenic sounds may cause behavioral disruption, and this can be quantified using a risk function that relates sound exposure to a measured behavioral response. Beaked whales are a taxon of deep diving whales that may be particularly susceptible to naval sonar as the species has been associated with sonar-related mass stranding events. Here we derive the first empirical risk function for Blainville's beaked whales (Mesoplodon densirostris by combining in situ data from passive acoustic monitoring of animal vocalizations and navy sonar operations with precise ship tracks and sound field modeling. The hydrophone array at the Atlantic Undersea Test and Evaluation Center, Bahamas, was used to locate vocalizing groups of Blainville's beaked whales and identify sonar transmissions before, during, and after Mid-Frequency Active (MFA sonar operations. Sonar transmission times and source levels were combined with ship tracks using a sound propagation model to estimate the received level (RL at each hydrophone. A generalized additive model was fitted to data to model the presence or absence of the start of foraging dives in 30-minute periods as a function of the corresponding sonar RL at the hydrophone closest to the center of each group. This model was then used to construct a risk function that can be used to estimate the probability of a behavioral change (cessation of foraging the individual members of a Blainville's beaked whale population might experience as a function of sonar RL. The function predicts a 0.5 probability of disturbance at a RL of 150 dBrms re µPa (CI: 144 to 155 This is 15dB lower than the level used historically by the US Navy in their risk assessments but 10 dB higher than the current 140 dB step-function.

  20. Use of Multibeam and Dual-Beam Sonar Systems to Observe Cavitating Flow Produced by Ferryboats: In a Marine Renewable Energy Perspective

    Directory of Open Access Journals (Sweden)

    Francisco Francisco

    2017-07-01

    Full Text Available With the prospect to deploy hydrokinetic energy converters in areas with heavy boat traffic, a study was conducted to observe and assess the depth range of cavitating flow produced by ferryboats in narrow channels. This study was conducted in the vicinity of Finnhamn Island in Stockholm Archipelago. The objectives of the survey were to assess whether the sonar systems were able to observe and measure the depth of what can be cavitating flow (in a form of convected cloud cavitation produced by one specific type of ferryboats frequently operating in that route, as well as investigate if the cavitating flow within the wake would propagate deep enough to disturb the water column underneath the surface. A multibeam and a dual-beam sonar systems were used as measurement instruments. The hypothesis was that strong and deep wake can disturb the optimal operation of a hydrokinetic energy converter, therefore causing damages to its rotors and hydrofoils. The results showed that both sonar system could detect cavitating flows including its strength, part of the geometrical shape and propagation depth. Moreover, the boat with a propeller thruster produced cavitating flow with an intense core reaching 4 m of depth while lasting approximately 90 s. The ferry with waterjet thruster produced a less intense cavitating flow; the core reached depths of approximately 6 m, and lasted about 90 s. From this study, it was concluded that multibeam and dual-beam sonar systems with operating frequencies higher than 200 kHz were able to detect cavitating flows in real conditions, as long as they are properly deployed and the data properly analyzed.

  1. Principles of underwater sound

    National Research Council Canada - National Science Library

    Urick, Robert J

    1983-01-01

    ... the immediately useful help they need for sonar problem solving. Its coverage is broad-ranging from the basic concepts of sound in the sea to making performance predictions in such applications as depth sounding, fish finding, and submarine detection...

  2. Directional sound beam emission from a configurable compact multi-source system

    KAUST Repository

    Zhao, Jiajun

    2018-01-12

    We propose to achieve efficient emission of highly directional sound beams from multiple monopole sources embedded in a subwavelength enclosure. Without the enclosure, the emitted sound fields have an indistinguishable or omnidirectional radiation directivity in far fields. The strong directivity formed in the presence of the enclosure is attributed to interference of sources under degenerate Mie resonances in the enclosure of anisotropic property. Our numerical simulations of sound emission from the sources demonstrate the radiation of a highly directed sound beam of unidirectional or bidirectional patterns, depending on how the sources are configured inside the enclosure. Our scheme, if achieved, can solve the challenging problem of poor directivity of a subwavelength sound system, and can guide beam forming and collimation by miniaturized devices.

  3. Multiresolution 3-D reconstruction from side-scan sonar images.

    Science.gov (United States)

    Coiras, Enrique; Petillot, Yvan; Lane, David M

    2007-02-01

    In this paper, a new method for the estimation of seabed elevation maps from side-scan sonar images is presented. The side-scan image formation process is represented by a Lambertian diffuse model, which is then inverted by a multiresolution optimization procedure inspired by expectation-maximization to account for the characteristics of the imaged seafloor region. On convergence of the model, approximations for seabed reflectivity, side-scan beam pattern, and seabed altitude are obtained. The performance of the system is evaluated against a real structure of known dimensions. Reconstruction results for images acquired by different sonar sensors are presented. Applications to augmented reality for the simulation of targets in sonar imagery are also discussed.

  4. The shock formation distance in a bounded sound beam of finite amplitude.

    Science.gov (United States)

    Tao, Chao; Ma, Jian; Zhu, Zhemin; Du, Gonghuan; Ping, Zihong

    2003-07-01

    This paper investigates the shock formation distance in a bounded sound beam of finite amplitude by solving the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation using frequency-domain numerical method. Simulation results reveal that, besides the nonlinearity and absorption, the diffraction is another important factor that affects the shock formation of a bounded sound beam. More detailed discussions of the shock formation in a bounded sound beam, such as the waveform of sound pressure and the spatial distribution of shock formation, are also presented and compared for different parameters.

  5. Cetacean Social Behavioral Response to Sonar Exposure

    Science.gov (United States)

    2015-09-30

    likely a social response which anticipates against potential loss of social cohesion, which may be induced by masking of their communication signals...Discrimination of fast click series produced by Risso’s dolphins for echolocation or communication . Wensveen P. et al (in review). The effectiveness of ramp...up of naval sonar to reduce sound levels received by marine mammals : experimental tests with humpback whales. Kvadsheim et al. (2015). The 3S2

  6. Modeling Effectiveness of Gradual Increases in Source Level to Mitigate Effects of Sonar on Marine Mammals

    NARCIS (Netherlands)

    Benda-Beckmann, A.M. von; Wensveen, P.J.; Kvadsheim, P.H.; Lam, F.P.A.; Miller, P.J.O.; Tyack, P.L.; Ainslie, M.A.

    2013-01-01

    Ramp-up or soft-start procedures (i.e., gradual increase in the source level) are used to mitigate the effect of sonar sound on marine mammals, although no one to date has tested whether ramp-up procedures are effective at reducing the effect of sound on marine mammals. We investigated the

  7. Optimization of Natural Frequencies and Sound Power of Beams Using Functionally Graded Material

    Directory of Open Access Journals (Sweden)

    Nabeel T. Alshabatat

    2014-01-01

    Full Text Available This paper presents a design method to optimize the material distribution of functionally graded beams with respect to some vibration and acoustic properties. The change of the material distribution through the beam length alters the stiffness and the mass of the beam. This can be used to alter a specific beam natural frequency. It can also be used to reduce the sound power radiated from the vibrating beam. Two novel volume fraction laws are used to describe the material volume distributions through the length of the FGM beam. The proposed method couples the finite element method (for the modal and harmonic analysis, Lumped Parameter Model (for calculating the power of sound radiation, and an optimization technique based on Genetic Algorithm. As a demonstration of this technique, the optimization procedure is applied to maximize the fundamental frequency of FGM cantilever and clamped beams and to minimize the sound radiation from vibrating clamped FGM beam at a specific frequency.

  8. Monitoring upstream sinkhole development by detailed sonar profiling

    Energy Technology Data Exchange (ETDEWEB)

    Rigbey, S. [Acres International Ltd., Niagara Falls, ON (Canada)

    2004-09-01

    This paper describes the development and use of a simple sonar system that has been used by engineers for routine monitoring of small sinkholes on the upstream face of a distressed earth dam. Improper construction of the dam led to the development of several sinkholes measuring 10 to 20 m in diameter upstream from the dam which is founded on deep alluvial sands and gravels. The dam has a central core of silt and leakage varies between 200 and 500 l/s, depending on the water level of the reservoir. The main issues with the upstream blanket are: improper fill placement due to the inability to dewater the area properly; omission of a filter material between the blanket and the alluvium foundation; thin placement of fill and runnelling of the blanket prior to impoundment; and, short upstream extent of the blanket. A downstream weighting toe of material was placed to address the seepage and piping that developed immediately following impounding. Other incidents continued over the years, such as downstream sinkholes, slumping of the crest and repairs about 12 years after construction. An inverter filter was also constructed to better control the seepage. Simple bathymetric surveys conducted by sounding the bottom of the reservoir from the ice surface each winter revealed the presence of several large sinkholes. Although infilling programs were conducted, sinkholes redeveloped after each program. The bathymetric surveys were found to be limited in accuracy and repeatability. Therefore, it was not possible to monitor small developments on a yearly basis. A 3-dimensional seepage model was developed to reconcile some of the unexplained piezometric patterns and to better understand the seepage patterns. However, this was also unsuccessful on its own. A trial sonar survey was then undertaken in 2002 by a Vancouver-based sonar company using an Imagenix profiling sonar head. It was successful in locating a small, previously unknown sinkhole measuring a few metres in diameter at

  9. Directional sound beam emission from a configurable compact multi-source system

    KAUST Repository

    Zhao, Jiajun; Jadhali, Rasha Al; Zhang, Likun; Wu, Ying

    2018-01-01

    We propose to achieve efficient emission of highly directional sound beams from multiple monopole sources embedded in a subwavelength enclosure. Without the enclosure, the emitted sound fields have an indistinguishable or omnidirectional radiation

  10. Experimental Investigation of Propagation and Reflection Phenomena in Finite Amplitude Sound Beams.

    Science.gov (United States)

    Averkiou, Michalakis Andrea

    Measurements of finite amplitude sound beams are compared with theoretical predictions based on the KZK equation. Attention is devoted to harmonic generation and shock formation related to a variety of propagation and reflection phenomena. Both focused and unfocused piston sources were used in the experiments. The nominal source parameters are piston radii of 6-25 mm, frequencies of 1-5 MHz, and focal lengths of 10-20 cm. The research may be divided into two parts: propagation and reflection of continuous-wave focused sound beams, and propagation of pulsed sound beams. In the first part, measurements of propagation curves and beam patterns of focused pistons in water, both in the free field and following reflection from curved targets, are presented. The measurements are compared with predictions from a computer model that solves the KZK equation in the frequency domain. A novel method for using focused beams to measure target curvature is developed. In the second part, measurements of pulsed sound beams from plane pistons in both water and glycerin are presented. Very short pulses (less than 2 cycles), tone bursts (5-30 cycles), and frequency modulated (FM) pulses (10-30 cycles) were measured. Acoustic saturation of pulse propagation in water is investigated. Self-demodulation of tone bursts and FM pulses was measured in glycerin, both in the near and far fields, on and off axis. All pulse measurements are compared with numerical results from a computer code that solves the KZK equation in the time domain. A quasilinear analytical solution for the entire axial field of a self-demodulating pulse is derived in the limit of strong absorption. Taken as a whole, the measurements provide a broad data base for sound beams of finite amplitude. Overall, outstanding agreement is obtained between theory and experiment.

  11. Reliability of fish size estimates obtained from multibeam imaging sonar

    Science.gov (United States)

    Hightower, Joseph E.; Magowan, Kevin J.; Brown, Lori M.; Fox, Dewayne A.

    2013-01-01

    Multibeam imaging sonars have considerable potential for use in fisheries surveys because the video-like images are easy to interpret, and they contain information about fish size, shape, and swimming behavior, as well as characteristics of occupied habitats. We examined images obtained using a dual-frequency identification sonar (DIDSON) multibeam sonar for Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, striped bass Morone saxatilis, white perch M. americana, and channel catfish Ictalurus punctatus of known size (20–141 cm) to determine the reliability of length estimates. For ranges up to 11 m, percent measurement error (sonar estimate – total length)/total length × 100 varied by species but was not related to the fish's range or aspect angle (orientation relative to the sonar beam). Least-square mean percent error was significantly different from 0.0 for Atlantic sturgeon (x̄  =  −8.34, SE  =  2.39) and white perch (x̄  = 14.48, SE  =  3.99) but not striped bass (x̄  =  3.71, SE  =  2.58) or channel catfish (x̄  = 3.97, SE  =  5.16). Underestimating lengths of Atlantic sturgeon may be due to difficulty in detecting the snout or the longer dorsal lobe of the heterocercal tail. White perch was the smallest species tested, and it had the largest percent measurement errors (both positive and negative) and the lowest percentage of images classified as good or acceptable. Automated length estimates for the four species using Echoview software varied with position in the view-field. Estimates tended to be low at more extreme azimuthal angles (fish's angle off-axis within the view-field), but mean and maximum estimates were highly correlated with total length. Software estimates also were biased by fish images partially outside the view-field and when acoustic crosstalk occurred (when a fish perpendicular to the sonar and at relatively close range is detected in the side lobes of adjacent beams). These sources of

  12. Anti-bat tiger moth sounds: Form and function

    Directory of Open Access Journals (Sweden)

    Aaron J. CORCORAN, William E. CONNER, Jesse R. BARBER

    2010-06-01

    Full Text Available The night sky is the venue of an ancient acoustic battle between echolocating bats and their insect prey. Many tiger moths (Lepidoptera: Arctiidae answer the attack calls of bats with a barrage of high frequency clicks. Some moth species use these clicks for acoustic aposematism and mimicry, and others for sonar jamming, however, most of the work on these defensive functions has been done on individual moth species. We here analyze the diversity of structure in tiger moth sounds from 26 species collected at three locations in North and South America. A principal components analysis of the anti-bat tiger moth sounds reveals that they vary markedly along three axes: (1 frequency, (2 duty cycle (sound production per unit time and frequency modulation, and (3 modulation cycle (clicks produced during flexion and relaxation of the sound producing tymbal structure. Tiger moth species appear to cluster into two distinct groups: one with low duty cycle and few clicks per modulation cycle that supports an acoustic aposematism function, and a second with high duty cycle and many clicks per modulation cycle that is consistent with a sonar jamming function. This is the first evidence from a community-level analysis to support multiple functions for tiger moth sounds. We also provide evidence supporting an evolutionary history for the development of these strategies. Furthermore, cross-correlation and spectrogram correlation measurements failed to support a “phantom echo” mechanism underlying sonar jamming, and instead point towards echo interference [Current Zoology 56 (3: 358–369, 2010].

  13. Swath sonar mapping of Earth's submarine plate boundaries

    Science.gov (United States)

    Carbotte, S. M.; Ferrini, V. L.; Celnick, M.; Nitsche, F. O.; Ryan, W. B. F.

    2014-12-01

    The recent loss of Malaysia Airlines flight MH370 in an area of the Indian Ocean where less than 5% of the seafloor is mapped with depth sounding data (Smith and Marks, EOS 2014) highlights the striking lack of detailed knowledge of the topography of the seabed for much of the worlds' oceans. Advances in swath sonar mapping technology over the past 30 years have led to dramatic improvements in our capability to map the seabed. However, the oceans are vast and only an estimated 10% of the seafloor has been mapped with these systems. Furthermore, the available coverage is highly heterogeneous and focused within areas of national strategic priority and community scientific interest. The major plate boundaries that encircle the globe, most of which are located in the submarine environment, have been a significant focus of marine geoscience research since the advent of swath sonar mapping. While the location of these plate boundaries are well defined from satellite-derived bathymetry, significant regions remain unmapped at the high-resolutions provided by swath sonars and that are needed to study active volcanic and tectonic plate boundary processes. Within the plate interiors, some fossil plate boundary zones, major hotspot volcanoes, and other volcanic provinces have been the focus of dedicated research programs. Away from these major tectonic structures, swath mapping coverage is limited to sparse ocean transit lines which often reveal previously unknown deep-sea channels and other little studied sedimentary structures not resolvable in existing low-resolution global compilations, highlighting the value of these data even in the tectonically quiet plate interiors. Here, we give an overview of multibeam swath sonar mapping of the major plate boundaries of the globe as extracted from public archives. Significant quantities of swath sonar data acquired from deep-sea regions are in restricted-access international archives. Open access to more of these data sets would

  14. SAFT-assisted sound beam focusing using phased arrays (PA-SAFT) for non-destructive evaluation

    Science.gov (United States)

    Nanekar, Paritosh; Kumar, Anish; Jayakumar, T.

    2015-04-01

    Focusing of sound has always been a subject of interest in ultrasonic non-destructive evaluation. An integrated approach to sound beam focusing using phased array and synthetic aperture focusing technique (PA-SAFT) has been developed in the authors' laboratory. The approach involves SAFT processing on ultrasonic B-scan image collected by a linear array transducer using a divergent sound beam. The objective is to achieve sound beam focusing using fewer elements than the ones required using conventional phased array. The effectiveness of the approach is demonstrated on aluminium blocks with artificial flaws and steel plate samples with embedded volumetric weld flaws, such as slag and clustered porosities. The results obtained by the PA-SAFT approach are found to be comparable to those obtained by conventional phased array and full matrix capture - total focusing method approaches.

  15. Principles of Sonar Performance Modeling

    NARCIS (Netherlands)

    Ainslie, M.A.

    2010-01-01

    Sonar performance modelling (SPM) is concerned with the prediction of quantitative measures of sonar performance, such as probability of detection. It is a multidisciplinary subject, requiring knowledge and expertise in the disparate fields of underwater acoustics, acoustical oceanography, sonar

  16. Benthic Mapping in Long Island Sound

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — QTCView is used with an incorporated depthfinder to create a sonar map of the bottom to the west of the Charles Island, in Long Island Sound in Connecticut waters....

  17. FPGA-Based Sonar Processing

    National Research Council Canada - National Science Library

    Graham, Paul; Nelson, Brent

    1998-01-01

    This paper presents the application of time-delay sonar beamforming and discusses a multi-board FPGA system for performing several variations of this beamforming method in real-time for realistic sonar arrays...

  18. Acoustic Imaging of Selected Areas of Gdansk Bay with the Aid of Parametric Echosounder and Side-Scan Sonar

    Directory of Open Access Journals (Sweden)

    Grelowska Grażyna

    2017-12-01

    Full Text Available The article presents and analyses the data recorded during sounding of the Gdansk Bay seabed with the aid of a parametric echosounder and a side-scan sonar. The accuracy of seabed structure examination, as a condition for obtaining valuable results, requires correct configuration of echolocation devices and proper calibration of peripheral devices, such as the survey unit geographical position sensor - GPS, the navigation unit, the MRU-Z sensor of pitch, roll and heave, and the sound velocity meter, which deliver the data to the bathymetric measurement system. Parametric seabed profilers deliver two types of data: the envelope, and the detailed echo signal without processing. The envelope is used for data visualisation in the form of online echograms, while the echo signal is stored for further analyses, to be performed using dedicated software or, after relevant conversion, in arbitrary programming environment1. The presented data analysis is illustrated by selected sample images recorded by the parametric echosounder and the side-scan sonar during Gdansk Bay sounding.

  19. Directional Acoustic Wave Manipulation by a Porpoise via Multiphase Forehead Structure

    Science.gov (United States)

    Zhang, Yu; Song, Zhongchang; Wang, Xianyan; Cao, Wenwu; Au, Whitlow W. L.

    2017-12-01

    Porpoises are small-toothed whales, and they can produce directional acoustic waves to detect and track prey with high resolution and a wide field of view. Their sound-source sizes are rather small in comparison with the wavelength so that beam control should be difficult according to textbook sonar theories. Here, we demonstrate that the multiphase material structure in a porpoise's forehead is the key to manipulating the directional acoustic field. Computed tomography (CT) derives the multiphase (bone-air-tissue) complex, tissue experiments obtain the density and sound-velocity multiphase gradient distributions, and acoustic fields and beam formation are numerically simulated. The results suggest the control of wave propagations and sound-beam formations is realized by cooperation of the whole forehead's tissues and structures. The melon size significantly impacts the side lobes of the beam and slightly influences the main beams, while the orientation of the vestibular sac mainly adjusts the main beams. By compressing the forehead complex, the sound beam can be expanded for near view. The porpoise's biosonar allows effective wave manipulations for its omnidirectional sound source, which can help the future development of miniaturized biomimetic projectors in underwater sonar, medical ultrasonography, and other ultrasonic imaging applications.

  20. Directionality of nose-emitted echolocation calls from bats without a nose-leaf (Plecotus auritus)

    DEFF Research Database (Denmark)

    Jakobsen, Lasse; Hallam, John; Moss, Cynthia F

    2018-01-01

    All echolocating bats and whales measured to date emit a directional bio-sonar beam that affords them a number of advantages over an omni-directional beam, i.e. reduced clutter, increased source level and inherent directional information. In this study we investigated the importance...... of a directional sound emission for navigation through echolocation by measuring the sonar beam of brown long-eared bats, Plecotus auritusP. auritus emits sound through the nostrils but has no external appendages to readily facility a directional sound emission as found in most nose emitters. The study shows...... that P. auritus, despite the lack of an external focusing apparatus, emits a directional echolocation beam (Directivity index=13 dB) and that the beam is more directional vertically (-6 dB angle at 22°) than horizontally (-6dB angle at 35°). Using a simple numerical model we find that the recorded...

  1. Slope angle studies from multibeam sonar data on three seamounts in Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Kodagali, V.N.

    Slope angles are powerful morphometric tools. Slope angle studies in manganese nodule areas using the Multi Beam Sonar (MBS) data is useful to the mining geologist. A technique to convert depth grid generated from MBS data to slope angle values data...

  2. The transmission of finite amplitude sound beam in multi-layered biological media

    Science.gov (United States)

    Liu, Xiaozhou; Li, Junlun; Yin, Chang; Gong, Xiufen; Zhang, Dong; Xue, Honghui

    2007-02-01

    Based on the Khokhlov Zabolotskaya Kuznetsov (KZK) equation, a model in the frequency domain is given to describe the transmission of finite amplitude sound beam in multi-layered biological media. Favorable agreement between the theoretical analyses and the measured results shows this approach could effectively describe the transmission of finite amplitude sound wave in multi-layered biological media.

  3. The transmission of finite amplitude sound beam in multi-layered biological media

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaozhou [Key Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093 (China)]. E-mail: xzliu@nju.edu.cn; Li, Junlun [Key Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093 (China); Yin, Chang [Key Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093 (China); Gong, Xiufen [Key Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093 (China); Zhang, Dong [Key Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093 (China); Xue, Honghui [Key Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093 (China)

    2007-02-19

    Based on the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, a model in the frequency domain is given to describe the transmission of finite amplitude sound beam in multi-layered biological media. Favorable agreement between the theoretical analyses and the measured results shows this approach could effectively describe the transmission of finite amplitude sound wave in multi-layered biological media.

  4. The transmission of finite amplitude sound beam in multi-layered biological media

    International Nuclear Information System (INIS)

    Liu, Xiaozhou; Li, Junlun; Yin, Chang; Gong, Xiufen; Zhang, Dong; Xue, Honghui

    2007-01-01

    Based on the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, a model in the frequency domain is given to describe the transmission of finite amplitude sound beam in multi-layered biological media. Favorable agreement between the theoretical analyses and the measured results shows this approach could effectively describe the transmission of finite amplitude sound wave in multi-layered biological media

  5. Vespertilionid bats control the width of their biosonar sound beam dynamically during prey pursuit

    DEFF Research Database (Denmark)

    Jakobsen, Lasse; Surlykke, Annemarie

    2010-01-01

    Animals using sound for communication emit directional signals, focusing most acoustic energy in one direction. Echolocating bats are listening for soft echoes from insects. Therefore, a directional biosonar sound beam greatly increases detection probability in the forward direction and decreases...

  6. NMFS Water Column Sonar Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water column sonar data are an important component of fishery independent surveys, habitat studies and other research. NMFS water column sonar data are archived here.

  7. Extraordinary lateral beaming of sound from a square-lattice phononic crystal

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Xiaoxue; Qiu, Chunyin; He, Hailong; Peng, Shasha; Ke, Manzhu [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Liu, Zhengyou, E-mail: zyliu@whu.edu.cn [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Institute for Advanced Studies, Wuhan University, Wuhan 430072 (China)

    2017-03-03

    Highlights: • An extraordinary lateral beaming phenomenon is observed in a finite phononic crystal made of square lattice. • The phenomenon can be explained by the equivalence of the states located around the four corners of the first Brillouin zone. • The lateral beaming behavior enables a simple design of acoustic beam splitters. • In some sense, the phenomenon can be described by a near zero refractive index. - Abstract: This work revisits the sound transmission through a finite phononic crystal of square lattice. In addition to a direct, ordinary transmission through the sample, an extraordinary lateral beaming effect is also observed. The phenomenon stems from the equivalence of the states located around the four corners of the first Brillouin zone. The experimental result agrees well with the theoretical prediction. The lateral beaming behavior enables a simple design for realizing acoustic beam splitters.

  8. On the Sediment Dynamics in a Tidally Energetic Channel: The Inner Sound, Northern Scotland

    Directory of Open Access Journals (Sweden)

    Jason McIlvenny

    2016-04-01

    Full Text Available Sediment banks within a fast-flowing tidal channel, the Inner Sound in the Pentland Firth, were mapped using multi-frequency side-scan sonar. This novel technique provides a new tool for seabed sediment and benthic habitat mapping. The sonar data are supplemented by sediment grab and ROV videos. The combined data provide detailed maps of persistent sand and shell banks present in the Sound despite the high energy environment. Acoustic Doppler Current Profiler (ADCP data and numerical model predictions were used to understand the hydrodynamics of the system. By combining the hydrodynamics and sediment distribution data, we explain the sediment dynamics in the area. Sediment particle shape and density, coupled with persistent features of the hydrodynamics, are the key factors in the distribution of sediment within the channel. Implications for tidal energy development planned for the Sound are discussed.

  9. Sidescan Sonar Image Matching Using Cross Correlation

    DEFF Research Database (Denmark)

    Thisen, Erik; Sørensen, Helge Bjarup Dissing; Stage, Bjarne

    2003-01-01

    When surveying an area for sea mines with a sidescan sonar, the ability to find the same object in two different sonar images is helpful to determine the nature of the object. The main problem with matching two sidescan sonar images is that a scene changes appearance when viewed from different vi...

  10. Sonar backscatter differentiation of dominant macrohabitat types in a hydrothermal vent field.

    Science.gov (United States)

    Durand, Sébastien; Legendre, Pierre; Juniper, S Kim

    2006-08-01

    Over the past 20 years, sonar remote sensing has opened ways of acquiring new spatial information on seafloor habitat and ecosystem properties. While some researchers are presently working to improve sonar methods so that broad-scale high-definition surveys can be effectively conducted for management purposes, others are trying to use these surveying techniques in more local areas. Because ecosystem management is scale-dependent, there is a need to acquire spatiotemporal knowledge over various scales to bridge the gap between already-acquired point-source data and information available at broader scales. Using a 675-kHz single-pencil-beam sonar mounted on the remotely operated vehicle ROPOS, 2200 m deep on the Juan de Fuca Ridge, East Pacific Rise, five dominant habitat types located in a hydrothermal vent field were identified and characterized by their sonar signatures. The data, collected at different altitudes from 1 to 10 m above the seafloor, were depth-normalized. We compared three ways of handling the echoes embedded in the backscatters to detect and differentiate the five habitat types; we examined the influence of footprint size on the discrimination capacity of the three methods; and we identified key variables, derived from echoes that characterize each habitat type. The first method used a set of variables describing echo shapes, and the second method used as variables the power intensity values found within the echoes, whereas the last method combined all these variables. Canonical discriminant analysis was used to discriminate among the five habitat types using the three methods. The discriminant models were constructed using 70% of the data while the remaining 30% were used for validation. The results showed that footprints 20-30 cm in diameter included a sufficient amount of spatial variation to make the sonar signatures sensitive to the habitat types, producing on average 82% correct classification. Smaller footprints produced lower percentages of

  11. Directionality of nose-emitted echolocation calls from bats without a nose leaf (Plecotus auritus).

    Science.gov (United States)

    Jakobsen, Lasse; Hallam, John; Moss, Cynthia F; Hedenström, Anders

    2018-02-13

    All echolocating bats and whales measured to date emit a directional bio-sonar beam that affords them a number of advantages over an omni-directional beam, i.e. reduced clutter, increased source level and inherent directional information. In this study, we investigated the importance of directional sound emission for navigation through echolocation by measuring the sonar beam of brown long-eared bats, Plecotus auritus Plecotus auritus emits sound through the nostrils but has no external appendages to readily facilitate a directional sound emission as found in most nose emitters. The study shows that P. auritus , despite lacking an external focusing apparatus, emits a directional echolocation beam (directivity index=13 dB) and that the beam is more directional vertically (-6 dB angle at 22 deg) than horizontally (-6 dB angle at 35 deg). Using a simple numerical model, we found that the recorded emission pattern is achievable if P. auritus emits sound through the nostrils as well as the mouth. The study thus supports the hypothesis that a directional echolocation beam is important for perception through echolocation and we propose that animals with similarly non-directional emitter characteristics may facilitate a directional sound emission by emitting sound through both the nostrils and the mouth. © 2018. Published by The Company of Biologists Ltd.

  12. Effects of Sound on the Behavior of Wild, Unrestrained Fish Schools.

    Science.gov (United States)

    Roberts, Louise; Cheesman, Samuel; Hawkins, Anthony D

    2016-01-01

    To assess and manage the impact of man-made sounds on fish, we need information on how behavior is affected. Here, wild unrestrained pelagic fish schools were observed under quiet conditions using sonar. Fish were exposed to synthetic piling sounds at different levels using custom-built sound projectors, and behavioral changes were examined. In some cases, the depth of schools changed after noise playback; full dispersal of schools was also evident. The methods we developed for examining the behavior of unrestrained fish to sound exposure have proved successful and may allow further testing of the relationship between responsiveness and sound level.

  13. Modeling and control of sound radiation by simply supported and cantilever beam coupled with smart material

    Directory of Open Access Journals (Sweden)

    Vitaly Makarenko

    2007-03-01

    Full Text Available  In this paper forced vibration of the beam due to bonded piezoelectric patch is considered. When an external excitation is applied to the beam, it starts to vibrate, and the resulting acoustic response is predicted from the analytical model, which is based on Bernoulli-Euler theory of beam vibration. Analytical research of the sound radiation by a finite elastic beam is done for criteria based on minimal total sound power level. Helmholtz equation and inhomogeneous differential equation for beam transverse motion defines the solution to this problem. Such solutions were found for boundary conditions of simply supported and cantilever beams. In order to solve the task two analytical methods were used for simply supported beam. The solutions received by Fourier transform and Green functions approach give the very similar results, thus, proving methods reliability. At the case studies the exerted voltage, phase, location and piezoelectric actuator length are varied in order to establish their influence on noise attenuation.

  14. Analysis of the Detectability of Sonar Under the Virtual Battlefield

    Directory of Open Access Journals (Sweden)

    Hou Chengyu

    2014-08-01

    Full Text Available Due to the high propagation speed and the low attenuation in the water, the sonar has played a crucial role in developing the ocean resources and the marine target detection. Therefore, simulation of the sonar detectability is indispensable to the virtual battlefield. This paper will combine the background noise model of the ocean, the reverberation model, the target strength model and the transmission loss to build the sonar performance model, and realize the calculation of the sonar detectability. Ultimately, the parameters’ effect in the sonar equation on the performance of the sonar detection is analyzed, and the validity of this model is verified by two serving sonars parameters.

  15. A micro-Doppler sonar for acoustic surveillance in sensor networks

    Science.gov (United States)

    Zhang, Zhaonian

    Wireless sensor networks have been employed in a wide variety of applications, despite the limited energy and communication resources at each sensor node. Low power custom VLSI chips implementing passive acoustic sensing algorithms have been successfully integrated into an acoustic surveillance unit and demonstrated for detection and location of sound sources. In this dissertation, I explore active and passive acoustic sensing techniques, signal processing and classification algorithms for detection and classification in a multinodal sensor network environment. I will present the design and characterization of a continuous-wave micro-Doppler sonar to image objects with articulated moving components. As an example application for this system, we use it to image gaits of humans and four-legged animals. I will present the micro-Doppler gait signatures of a walking person, a dog and a horse. I will discuss the resolution and range of this micro-Doppler sonar and use experimental results to support the theoretical analyses. In order to reduce the data rate and make the system amenable to wireless sensor networks, I will present a second micro-Doppler sonar that uses bandpass sampling for data acquisition. Speech recognition algorithms are explored for biometric identifications from one's gait, and I will present and compare the classification performance of the two systems. The acoustic micro-Doppler sonar design and biometric identification results are the first in the field as the previous work used either video camera or microwave technology. I will also review bearing estimation algorithms and present results of applying these algorithms for bearing estimation and tracking of moving vehicles. Another major source of the power consumption at each sensor node is the wireless interface. To address the need of low power communications in a wireless sensor network, I will also discuss the design and implementation of ultra wideband transmitters in a three dimensional

  16. Radar, sonar, and holography an introduction

    CERN Document Server

    Kock, Winston E

    1974-01-01

    Radar, Sonar, and Holography: An Introduction provides an introduction to the technology of radar and sonar. Because the new science of holography is affecting both these fields quite strongly, the book includes an explanation of the fundamental principles underlying this new art (including the subjects of wave coherence, interference, and diffraction) and of the hologram process itself. Finally, numerous examples are discussed which show how holography is providing new horizons to radar and sonar systems. The book thus also provides a simple approach to the new technology of holography. The

  17. Multibeam sonar backscatter data processing

    Science.gov (United States)

    Schimel, Alexandre C. G.; Beaudoin, Jonathan; Parnum, Iain M.; Le Bas, Tim; Schmidt, Val; Keith, Gordon; Ierodiaconou, Daniel

    2018-06-01

    Multibeam sonar systems now routinely record seafloor backscatter data, which are processed into backscatter mosaics and angular responses, both of which can assist in identifying seafloor types and morphology. Those data products are obtained from the multibeam sonar raw data files through a sequence of data processing stages that follows a basic plan, but the implementation of which varies greatly between sonar systems and software. In this article, we provide a comprehensive review of this backscatter data processing chain, with a focus on the variability in the possible implementation of each processing stage. Our objective for undertaking this task is twofold: (1) to provide an overview of backscatter data processing for the consideration of the general user and (2) to provide suggestions to multibeam sonar manufacturers, software providers and the operators of these systems and software for eventually reducing the lack of control, uncertainty and variability associated with current data processing implementations and the resulting backscatter data products. One such suggestion is the adoption of a nomenclature for increasingly refined levels of processing, akin to the nomenclature adopted for satellite remote-sensing data deliverables.

  18. Application of passive sonar technology to mineral processing and oil sands applications : if you can measure it, you can manage it

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, C.; Viega, J.; Fernald, M. [CiDRA Corp., Wallingford, CT (United States)

    2007-07-01

    SONAR-based flow and entrained air measurement instruments were described. This new class of industrial flow and compositional analyzers was developed by CiDRA to provide new measurement insight and quantifiable value to industrial process operators. Passive sonar array-based processing units have been installed worldwide in several industrial applications and are particularly suited for a wide range of mineral processing applications, including slurry flow rate measurement and fluid characterization. This paper also described the SONAR-based, clamp-on SONARtrac technology, a scalable platform that provides several other value added measurements and information such as speed of sound, entrained air/gas, gas hold-up, and velocity profile. Oil sands, tailings and bitumen slurries present considerable measurement challenges for in-line flow measurement devices in terms of measurement accuracy, reliability and maintenance. The sonar-based technology platform has been used in a variety of oil sands processes, hydrotransport, and minerals beneficiation applications. This paper described these applications with particular reference to difficult slurry flow measurement and control in the areas of comminution and flotation such as mill discharge, hydrocyclone feed/overflow, final concentrate, thickener discharge, and tailings. 5 refs., 4 tabs., 23 figs.

  19. Seafloor Characterisation of the Gakkel Ridge using Multibeam Sonar, Backscatter and Sidescan Data

    Science.gov (United States)

    Hatzky, J.; Schenke, H. W.

    2003-04-01

    The Gakkel Ridge in the Arctic Ocean was the object of the Arctic Mid-Ocean Ridge Expedition (AMORE) which was carried out by the research icebreakers R/V "Polarstern" (Germany) and USCGC "Healy" (USA) in the boreal summer 2001. This largely unexplored mid-ocean ridge (MOR) is of particular scientific interest due to its volcanic activity and tectonic structure. With spreading rates of 13mm/a in the western and 6 mm/a in the eastern part Gakkel Ridge is the slowest spreading MOR on earth (Michael et al., 2001). The surveyed area which is situated between 82°N / 8°W and 87°N / 75°E has a length of 8890 km and a varying width from 18 to 46 km. The range of measured depths reaches from 566 m on the top of a huge seamount to 5673 m in the central rift valley. Prominent underwater features of remarkable morphologic diversity (e.g. small volcanoes embedded in massive ridge flanks) were discovered in this region. One of the most important goals of the expedition was the compilation of a high resolution grid which serves as basis for a three dimensional digital terrain model (DTM), the derivation of contour lines and the production of bathymetric maps. Accordingly, two hull-mounted multibeam sonars were used for the depth data acquisition: the "Hydrosweep DS-2" system onboard "Polarstern" and the "Seabeam 2112" system onboard "Healy". In order to calculate a combined grid out of two independent data sets different technical specifications of both sonar systems (e.g. frequency, opening angle, number of beams, accuracy) had to be taken into account. Dense sea ice cover made the sonar measurements difficult. Thick floes caused hydroacoustic disturbances that heavily debased the data quality. Outliers and blunders of depths and navigation data had to be corrected in a drawn-out post-processing by appropriate software tools. Both echo sounding systems recorded backscatter information and sidescan data during the entire cruise. Onboard "Polarstern" the sub-bottom profiling

  20. The fusion of large scale classified side-scan sonar image mosaics.

    Science.gov (United States)

    Reed, Scott; Tena, Ruiz Ioseba; Capus, Chris; Petillot, Yvan

    2006-07-01

    This paper presents a unified framework for the creation of classified maps of the seafloor from sonar imagery. Significant challenges in photometric correction, classification, navigation and registration, and image fusion are addressed. The techniques described are directly applicable to a range of remote sensing problems. Recent advances in side-scan data correction are incorporated to compensate for the sonar beam pattern and motion of the acquisition platform. The corrected images are segmented using pixel-based textural features and standard classifiers. In parallel, the navigation of the sonar device is processed using Kalman filtering techniques. A simultaneous localization and mapping framework is adopted to improve the navigation accuracy and produce georeferenced mosaics of the segmented side-scan data. These are fused within a Markovian framework and two fusion models are presented. The first uses a voting scheme regularized by an isotropic Markov random field and is applicable when the reliability of each information source is unknown. The Markov model is also used to inpaint regions where no final classification decision can be reached using pixel level fusion. The second model formally introduces the reliability of each information source into a probabilistic model. Evaluation of the two models using both synthetic images and real data from a large scale survey shows significant quantitative and qualitative improvement using the fusion approach.

  1. High frequency sonar variability in littoral environments: Irregular particles and bubbles

    Science.gov (United States)

    Richards, Simon D.; Leighton, Timothy G.; White, Paul R.

    2002-11-01

    Littoral environments may be characterized by high concentrations of suspended particles. Such suspensions contribute to attenuation through visco-inertial absorption and scattering and may therefore be partially responsible for the observed variability in high frequency sonar performance in littoral environments. Microbubbles which are prevalent in littoral waters also contribute to volume attenuation through radiation, viscous and thermal damping and cause dispersion. The attenuation due to a polydisperse suspension of particles with depth-dependent concentration has been included in a sonar model. The effects of a depth-dependent, polydisperse population of microbubbles on attenuation, sound speed and volume reverberation are also included. Marine suspensions are characterized by nonspherical particles, often plate-like clay particles. Measurements of absorption in dilute suspensions of nonspherical particles have shown disagreement with predictions of spherical particle models. These measurements have been reanalyzed using three techniques for particle sizing: laser diffraction, gravitational sedimentation, and centrifugal sedimentation, highlighting the difficulty of characterizing polydisperse suspensions of irregular particles. The measurements have been compared with predictions of a model for suspensions of oblate spheroids. Excellent agreement is obtained between this model and the measurements for kaolin particles, without requiring any a priori knowledge of the measurements.

  2. A Study to Interpret the Biological Significance of Behavior Associated with 3S Experimental Sonar Exposures

    Science.gov (United States)

    2015-09-30

    species; 2.) quantitative comparison of behavior, and behavioral changes, during sonar presentation and playback of killer whale sounds across the 3S... foraging dives were pre-classified from the remaining dives first by determining a break-point depth in the depth versus duration relationship, and then...AIC point to divide dive depth versus duration relationships (Fig. 2). 50.8% of dives greater than 15m in depth were classified as foraging dives

  3. Sonar Tank Area

    Data.gov (United States)

    Federal Laboratory Consortium — The Sonar Tank Facility permits low cost initial 'wet' testing and check out prior to full scale deployment at sea. It can manage controlled conditions calibration...

  4. High-Resolution Sonars: What Resolution Do We Need for Target Recognition?

    Directory of Open Access Journals (Sweden)

    Pailhas Yan

    2010-01-01

    Full Text Available Target recognition in sonar imagery has long been an active research area in the maritime domain, especially in the mine-counter measure context. Recently it has received even more attention as new sensors with increased resolution have been developed; new threats to critical maritime assets and a new paradigm for target recognition based on autonomous platforms have emerged. With the recent introduction of Synthetic Aperture Sonar systems and high-frequency sonars, sonar resolution has dramatically increased and noise levels decreased. Sonar images are distance images but at high resolution they tend to appear visually as optical images. Traditionally algorithms have been developed specifically for imaging sonars because of their limited resolution and high noise levels. With high-resolution sonars, algorithms developed in the image processing field for natural images become applicable. However, the lack of large datasets has hampered the development of such algorithms. Here we present a fast and realistic sonar simulator enabling development and evaluation of such algorithms.We develop a classifier and then analyse its performances using our simulated synthetic sonar images. Finally, we discuss sensor resolution requirements to achieve effective classification of various targets and demonstrate that with high resolution sonars target highlight analysis is the key for target recognition.

  5. Digital sonar design in underwater acoustics principles and applications

    CERN Document Server

    Li, Qihu

    2012-01-01

    "Digital Sonar Design in Underwater Acoustics Principles and Applications" provides comprehensive and up-to-date coverage of research on sonar design, including the basic theory and techniques of digital signal processing, basic concept of information theory, ocean acoustics, underwater acoustic signal propagation theory, and underwater signal processing theory. This book discusses the general design procedure and approaches to implementation, the design method, system simulation theory and techniques, sonar tests in the laboratory, lake and sea, and practical validation criteria and methods for digital sonar design. It is intended for researchers in the fields of underwater signal processing and sonar design, and also for navy officers and ocean explorers. Qihu Li is a professor at the Institute of Acoustics, Chinese Academy of Sciences, and an academician of the Chinese Academy of Sciences.

  6. Adaptive motion compensation in sonar array processing

    NARCIS (Netherlands)

    Groen, J.

    2006-01-01

    In recent years, sonar performance has mainly improved via a significant increase in array ap-erture, signal bandwidth and computational power. This thesis aims at improving sonar array processing techniques based on these three steps forward. In applications such as anti-submarine warfare and mine

  7. Sonar path correction in synthetic aperture processing

    NARCIS (Netherlands)

    Groen, J.; Hansen, R.E.; Sabel, J.C.

    2003-01-01

    In the next generation of mine hunting sonars, in particular on Autonomous Underwater Vehicles (AUVs), Synthetic Aperture Sonar (SAS) will play an important role. The benefit of SAS is to increase resolution and signal-tonoise ratio by coherent processing of successive pings. A challenge in SAS is

  8. Converting a Monopole Emission into a Dipole Using a Subwavelength Structure

    Science.gov (United States)

    Fan, Xu-Dong; Zhu, Yi-Fan; Liang, Bin; Cheng, Jian-chun; Zhang, Likun

    2018-03-01

    High-efficiency emission of multipoles is unachievable by a source much smaller than the wavelength, preventing compact acoustic devices for generating directional sound beams. Here, we present a primary scheme towards solving this problem by numerically and experimentally enclosing a monopole sound source in a structure with a dimension of around 1 /10 sound wavelength to emit a dipolar field. The radiated sound power is found to be more than twice that of a bare dipole. Our study of efficient emission of directional low-frequency sound from a monopole source in a subwavelength space may have applications such as focused ultrasound for imaging, directional underwater sound beams, miniaturized sonar, etc.

  9. Side-Scan-Sonar Points for Hudson River, NY

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Side Scan Point Files. These points correspond to individual pings which produced hte side-scan-sonar backscatter imagery. Sonar data were collected November 6 to...

  10. Long range echo classification for minehunting sonars

    NARCIS (Netherlands)

    Theije, P.A.M. de; Groen, J.; Sabel, J.C.

    2006-01-01

    This paper focesus on single-ping classification of sea mines, at a range of about 400 m, and combining a hull mounted sonar (HMS) and a propelled variable-depth sonar (PDVS). The deleoped classifier is trained and tested on a set of simulated realistic echoes of mines and non-mines. As the mines

  11. High-Resolution Multibeam Sonar Survey and Interactive 3-D Exploration of the D-Day Wrecks off Normandy

    Science.gov (United States)

    Mayer, L. A.; Calder, B.; Schmidt, J. S.

    2003-12-01

    Historically, archaeological investigations use sidescan sonar and marine magnetometers as initial search tools. Targets are then examined through direct observation by divers, video, or photographs. Magnetometers can demonstrate the presence, absence, and relative susceptibility of ferrous objects but provide little indication of the nature of the target. Sidescan sonar can present a clear image of the overall nature of a target and its surrounding environment, but the sidescan image is often distorted and contains little information about the true 3-D shape of the object. Optical techniques allow precise identification of objects but suffer from very limited range, even in the best of situations. Modern high-resolution multibeam sonar offers an opportunity to cover a relatively large area from a safe distance above the target, while resolving the true three-dimensional (3-D) shape of the object with centimeter-level resolution. The combination of 3-D mapping and interactive 3-D visualization techniques provides a powerful new means to explore underwater artifacts. A clear demonstration of the applicability of high-resolution multibeam sonar to wreck and artifact investigations occurred when the Naval Historical Center (NHC), the Center for Coastal and Ocean Mapping (CCOM) at the University of New Hampshire, and Reson Inc., collaborated to explore the state of preservation and impact on the surrounding environment of a series of wrecks located off the coast of Normandy, France, adjacent to the American landing sectors The survey augmented previously collected magnetometer and high-resolution sidescan sonar data using a Reson 8125 high-resolution focused multibeam sonar with 240, 0.5° (at nadir) beams distributed over a 120° swath. The team investigated 21 areas in water depths ranging from about three -to 30 meters (m); some areas contained individual targets such as landing craft, barges, a destroyer, troop carrier, etc., while others contained multiple smaller

  12. Review of research on sonar imaging technology in China

    Science.gov (United States)

    Guo, Haitao; Li, Renping; Xu, Feng; Liu, Liyuan

    2013-11-01

    Over the past 20 years, sonar imaging technology particularly for the high-technology sector has been a focus of research, in which many developed countries, especially those with coast lines, have been competing with each other. It has seen a rapid development with increasing widespread applications that has played an important and irreplaceable role in underwater exploration with great prospects for social, economic, scientific, and military benefits. The fundamental techniques underlying sonar imaging, including multi-beamforming, synthetic-aperture and inverse synthetic-aperture sonar, acoustic lensing, and acoustical holography, are described in this paper. This is followed by a comprehensive and systematic review on the advantages and disadvantages of these imaging techniques, applicability conditions, development trends, new ideas, new methods, and improvements in old methods over recent years with an emphasis on the situation in China, along with a bold and constructive prediction to some development characteristics of sonar imaging technology in the near future in China. The perspectives presented in this paper are offered with the idea of providing some degree of guidance and promotion of research on sonar imaging technology.

  13. Insights into Optimal Soft Start and Shutdown Procedures for Stationary or Moving Sound Sources

    NARCIS (Netherlands)

    Ainslie, M.A.; Benda-Beckmann, A.M. von

    2012-01-01

    To reduce the risk of impact on marine life of underwater sound generated by anthropogenic activities (such as offshore construction, seismic surveys and sonar searches), various mitigation measures are often put in place. Two commonly adopted mitigation measures are the soft start (or "ramp-up" –

  14. Directionality of sperm whale sonar clicks and its relation to piston radiation theory

    DEFF Research Database (Denmark)

    Beedholm, K.; Møhl, Bertel

    2006-01-01

    This paper investigates the applicability to sperm whales of the theory of sound radiating from a piston. The theory is applied to a physical model and to a series of sperm whale clicks. Results show that wave forms of off-axis signals can be reproduced by convolving an on-axis signal...... with the spatial impulse response of a piston. The angle of a recorded click can be estimated as the angle producing the spatial impulse response that gives the best match with the observation when convolved with the on-axis wave form. It is concluded that piston theory applies to sperm whale sonar click emission....

  15. Numerical Solution of the Kzk Equation for Pulsed Finite Amplitude Sound Beams in Thermoviscous Fluids

    Science.gov (United States)

    Lee, Yang-Sub

    A time-domain numerical algorithm for solving the KZK (Khokhlov-Zabolotskaya-Kuznetsov) nonlinear parabolic wave equation is developed for pulsed, axisymmetric, finite amplitude sound beams in thermoviscous fluids. The KZK equation accounts for the combined effects of diffraction, absorption, and nonlinearity at the same order of approximation. The accuracy of the algorithm is established via comparison with analytical solutions for several limiting cases, and with numerical results obtained from a widely used algorithm for solving the KZK equation in the frequency domain. The time domain algorithm is used to investigate waveform distortion and shock formation in directive sound beams radiated by pulsed circular piston sources. New results include predictions for the entire process of self-demodulation, and for the effect of frequency modulation on pulse envelope distortion. Numerical results are compared with measurements, and focused sources are investigated briefly.

  16. Implementation of Signal Processing in Stereo-Scopic Active Sonar Using Heterodyne System

    Directory of Open Access Journals (Sweden)

    BOKHARI Syed Umar

    2012-10-01

    Full Text Available “SONAR” is an acronym for sound ranging and navigation. It uses sound waves to detect an object in the surroundings and calculate its distance. This device has a very important applications in shipbuilding industry and military systems. Moreover it’s also being extensively used in deep sea research of new species of plants and minerals, where it is practically impossible for humans to go. The most important feature of this system is the usage of ultrasonicfrequency to detect objects that are important for data collection or detection. Transmitting an ultra sonic frequency using an electronic oscillator is not a very difficult task, the real challenge is to design a reciever that could carry out a particular modulation technique to convert an ultra-sonic frequency to an audiblefrequency. In this paper, we propose aseteroscopic active SONAR proto-type. Further, we performed a seriers of expeirments using modulation techniques. The results obtained from the experiments gives us a braod understanding of the different behaviour of asignal.

  17. Echolocation call intensity and directionality in flying short-tailed fruit bats, Carollia perspicillata (Phyllostomidae)

    DEFF Research Database (Denmark)

    Brinkløv, Signe; Jakobsen, Lasse; Ratcliffe, John M

    2011-01-01

    The directionality of bat echolocation calls defines the width of bats' sonar "view," while call intensity directly influences detection range since adequate sound energy must impinge upon objects to return audible echoes. Both are thus crucial parameters for understanding biosonar signal design....... a longer and narrower sonar range than previously thought. C. perspicillata orient and forage in the forest interior and the narrow beam might be adaptive in clutter, by reducing the number and intensity of off-axis echoes....

  18. Seafloor identification in sonar imagery via simulations of Helmholtz equations and discrete optimization

    Science.gov (United States)

    Engquist, Björn; Frederick, Christina; Huynh, Quyen; Zhou, Haomin

    2017-06-01

    We present a multiscale approach for identifying features in ocean beds by solving inverse problems in high frequency seafloor acoustics. The setting is based on Sound Navigation And Ranging (SONAR) imaging used in scientific, commercial, and military applications. The forward model incorporates multiscale simulations, by coupling Helmholtz equations and geometrical optics for a wide range of spatial scales in the seafloor geometry. This allows for detailed recovery of seafloor parameters including material type. Simulated backscattered data is generated using numerical microlocal analysis techniques. In order to lower the computational cost of the large-scale simulations in the inversion process, we take advantage of a pre-computed library of representative acoustic responses from various seafloor parameterizations.

  19. Audio-Visual Fusion for Sound Source Localization and Improved Attention

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byoung Gi; Choi, Jong Suk; Yoon, Sang Suk; Choi, Mun Taek; Kim, Mun Sang [Korea Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Dai Jin [Pohang University of Science and Technology, Pohang (Korea, Republic of)

    2011-07-15

    Service robots are equipped with various sensors such as vision camera, sonar sensor, laser scanner, and microphones. Although these sensors have their own functions, some of them can be made to work together and perform more complicated functions. AudioFvisual fusion is a typical and powerful combination of audio and video sensors, because audio information is complementary to visual information and vice versa. Human beings also mainly depend on visual and auditory information in their daily life. In this paper, we conduct two studies using audioFvision fusion: one is on enhancing the performance of sound localization, and the other is on improving robot attention through sound localization and face detection.

  20. Audio-Visual Fusion for Sound Source Localization and Improved Attention

    International Nuclear Information System (INIS)

    Lee, Byoung Gi; Choi, Jong Suk; Yoon, Sang Suk; Choi, Mun Taek; Kim, Mun Sang; Kim, Dai Jin

    2011-01-01

    Service robots are equipped with various sensors such as vision camera, sonar sensor, laser scanner, and microphones. Although these sensors have their own functions, some of them can be made to work together and perform more complicated functions. AudioFvisual fusion is a typical and powerful combination of audio and video sensors, because audio information is complementary to visual information and vice versa. Human beings also mainly depend on visual and auditory information in their daily life. In this paper, we conduct two studies using audioFvision fusion: one is on enhancing the performance of sound localization, and the other is on improving robot attention through sound localization and face detection

  1. The Method of a Standalone Functional Verifying Operability of Sonar Control Systems

    Directory of Open Access Journals (Sweden)

    A. A. Sotnikov

    2014-01-01

    Full Text Available This article describes a method of standalone verifying sonar control system, which is based on functional checking of control system operability.The main features of realized method are a development of the valid mathematic model for simulation of sonar signals at the point of hydroacoustic antenna, a valid representation of the sonar control system modes as a discrete Markov model, providing functional object verification in real time mode.Some ways are proposed to control computational complexity in case of insufficient computing resources of the simulation equipment, namely the way of model functionality reduction and the way of adequacy reduction.Experiments were made using testing equipment, which was developed by department of Research Institute of Information Control System at Bauman Moscow State Technical University to verify technical validity of industrial sonar complexes.On-board software was artificially changed to create malfunctions in functionality of sonar control systems during the verifying process in order to estimate verifying system performances.The method efficiency was proved by the theory and experiment results in comparison with the basic methodology of verifying technical systems.This method could be also used in debugging of on-board software of sonar complexes and in development of new promising algorithms of sonar signal processing.

  2. Digital Signal Processing Applied to the Modernization Of Polish Navy Sonars

    Directory of Open Access Journals (Sweden)

    Marszal Jacek

    2014-04-01

    Full Text Available The article presents the equipment and digital signal processing methods used for modernizing the Polish Navy’s sonars. With the rapid advancement of electronic technologies and digital signal processing methods, electronic systems, including sonars, become obsolete very quickly. In the late 1990s a team of researchers of the Department of Marine Electronics Systems, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, began work on modernizing existing sonar systems for the Polish Navy. As part of the effort, a methodology of sonar modernization was implemented involving a complete replacement of existing electronic components with newly designed ones by using bespoke systems and methods of digital signal processing. Large and expensive systems of ultrasound transducers and their dipping and stabilisation systems underwent necessary repairs but were otherwise left unchanged. As a result, between 2001 and 2014 the Gdansk University of Technology helped to modernize 30 sonars of different types.

  3. A Study for Optimum Survey Method of Underwater Structure Using the Dual Sonar Sensor

    Directory of Open Access Journals (Sweden)

    Youngseok Kim

    2017-01-01

    Full Text Available We have developed dual sonar equipment and an improved operating method for improving resolution in order to solve the problems of limitations of the optical equipment and the application method of SSS (side scan sonar in the investigation of damage of underwater structures. We analyzed the influence factors of the resolution of sonar data through the comparison of resolution and data quality in indoor test. Also we confirmed the problems about the overlapping area of the dual sonar. Depth and distance were analyzed as major influencing factors for survey angle. Specimens were scanned while adjusting distance and towfish angle according to depth change in order to verify applicability of the developed dual sonar in the field experiment. Optimal resolution was found to be 3 cm in specimen spacing, and 20 sample data items were extracted. We developed the regression model based on the multiple regression analysis and developed the RealDualSONAR-DAQ tool, the dual sonar optimum operating method program based on proposed correlation equations. We can use the developed tools to get the value of the major influencing factors for dual sonar operation and obtain high quality sonar data to analyze damage of underwater structures.

  4. Water Column Sonar Data Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The collection and analysis of water column sonar data is a relatively new avenue of research into the marine environment. Primary uses include assessing biological...

  5. Velocity of sound measurements in gaseous per-fluorocarbons and their custom mixtures

    CERN Document Server

    Vacek, V; Lindsay, S

    2000-01-01

    An inexpensive sonar instrument was prepared for measurements of sound velocity in two fluorocarbon vapors; per-fluoro-n-propane (C3F8), per-fluoro-n-butane (C4F10), and their custom mixtures. The apparatus, measurement principle and instrument software are described. All sound velocity measurements in per-fluorocarbons were made in the low pressure range between 0.01 and 0.4 MPa, and at temperatures between 253 and 303 K. The purity of the C3F8 and C4F10 samples was checked using gas chromatography. Uncertainties in the speed of sound measurements were better than ± 0.1 %. Comparisons were made with theoretical predictions of sound velocity for the two individual components. The instrument was then used for concentration monitoring of custom C3F8/C4F10 mixtures.

  6. Sea ice draft in the Weddell Sea, measured by upward looking sonars

    Directory of Open Access Journals (Sweden)

    A. Behrendt

    2013-06-01

    Full Text Available The presented database contains time-referenced sea ice draft values from upward looking sonar (ULS measurements in the Weddell Sea, Antarctica. The sea ice draft data can be used to infer the thickness of the ice. They were collected during the period 1990–2008. In total, the database includes measurements from 13 locations in the Weddell Sea and was generated from more than 3.7 million measurements of sea ice draft. The files contain uncorrected raw drafts, corrected drafts and the basic parameters measured by the ULS. The measurement principle, the data processing procedure and the quality control are described in detail. To account for the unknown speed of sound in the water column above the ULS, two correction methods were applied to the draft data. The first method is based on defining a reference level from the identification of open water leads. The second method uses a model of sound speed in the oceanic mixed layer and is applied to ice draft in austral winter. Both methods are discussed and their accuracy is estimated. Finally, selected results of the processing are presented. The data can be downloaded from doi:10.1594/PANGAEA.785565.

  7. An Improved Prediction Model for the Impact Sound Level of Lightweight Floors: Introducing Decoupled Floor-Ceiling and Beam-Plate Moment

    DEFF Research Database (Denmark)

    Mosharrof, Mohammad Sazzad; Brunskog, Jonas; Ljunggren, Fredrik

    2011-01-01

    the impact sound pressure level in a receiving room for a coupled floor structure where floor and ceiling are rigidly connected by beams. A theoretical model for predicting the impact sound level for a decoupled floor structure, which has no rigid mechanical connections between the floor and the ceiling......, is developed. An analytical method has been implemented, where a spatial Fourier transform method as well as the Poisson’s sum formula is applied to model transformed plate displacements. Radiated sound power was calculated from these displacements and normalized sound pressure levels were calculated in one...... and is found to be dependent on frequency, showing significant improvement in predicting impact sound level at high frequency region....

  8. Reconstruction of Sound Source Pressures in an Enclosure Using the Phased Beam Tracing Method

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho; Ih, Jeong-Guon

    2009-01-01

    . First, surfaces of an extended source are divided into reasonably small segments. From each source segment, one beam is projected into the field and all emitted beams are traced. Radiated beams from the source reach array sensors after traveling various paths including the wall reflections. Collecting...... all the pressure histories at the field points, source-observer relations can be constructed in a matrix-vector form for each frequency. By multiplying the measured field data with the pseudo-inverse of the calculated transfer function, one obtains the distribution of source pressure. An omni......-directional sphere and a cubic source in a rectangular enclosure were taken as examples in the simulation tests. A reconstruction error was investigated by Monte Carlo simulation in terms of field point locations. When the source information was reconstructed by the present method, it was shown that the sound power...

  9. NPS ARIES Forward Look Sonar Integration

    National Research Council Canada - National Science Library

    Healey, A. J; Horner, D. P

    2004-01-01

    This work integrated an experimental Blazed Array Forward Looking Sonar (FLS) developed by the University of Washington, Applied Physics Laboratories into the ARIES autonomous underwater vehicle (AUV...

  10. A Mobile Robot Sonar System with Obstacle Avoidance.

    Science.gov (United States)

    1994-03-01

    WITH OBSTACLE - AVOIDANCE __ by __ Patrick Gerard Byrne March 1994 Thesis Advisor : Yutaka Kanayama Approved for public release; distribution is...point p is on a line L whose normal has an orientation a and whose distance from the origin is r (Figure 5). This method has an advantage in expressing...sonar(FRONTR); Wine(&pl); while(hitl I >’- 100.0 11 hitl 1 - 0.0 ){ hitl I = sonar(FRONTR); I skipO; line(&p3); gat- robO (&posit 1); while(positl.x

  11. Airborne Low-Frequency Sonar (ALFS) Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The ALFS lab is dedicated to support acoustic data analysis and processing software support to the AN/AQS-22 dipping sonar system. It includes stand-alone Software...

  12. Sea-floor morphology and sedimentary environments in western Block Island Sound, offshore of Fishers Island, New York

    Science.gov (United States)

    McMullen, Katherine Y.; Poppe, Lawrence J.; Danforth, William W.; Blackwood, Dann S.; Winner, William G.; Parker, Castle E.

    2015-01-01

    Multibeam-bathymetric and sidescan-sonar data, collected by the National Oceanic and Atmospheric Administration in a 114-square-kilometer area of Block Island Sound, southeast of Fishers Island, New York, are combined with sediment samples and bottom photography collected by the U.S. Geological Survey from 36 stations in this area in order to interpret sea-floor features and sedimentary environments. These interpretations and datasets provide base maps for studies on benthic ecology and resource management. The geologic features and sedimentary environments on the sea floor are products of the area’s glacial history and modern processes. These features include bedrock, drumlins, boulders, cobbles, large current-scoured bathymetric depressions, obstacle marks, and glaciolacustrine sediments found in high-energy sedimentary environments of erosion or nondeposition; and sand waves and megaripples in sedimentary environments characterized by coarse-grained bedload transport. Trawl marks are preserved in lower energy environments of sorting and reworking. This report releases the multibeam-bathymetric, sidescan-sonar, sediment, and photographic data and interpretations of the features and sedimentary environments in Block Island Sound, offshore Fishers Island.

  13. Cleaning Massive Sonar Point Clouds

    DEFF Research Database (Denmark)

    Arge, Lars Allan; Larsen, Kasper Green; Mølhave, Thomas

    2010-01-01

    We consider the problem of automatically cleaning massive sonar data point clouds, that is, the problem of automatically removing noisy points that for example appear as a result of scans of (shoals of) fish, multiple reflections, scanner self-reflections, refraction in gas bubbles, and so on. We...

  14. Reflection and Transmission of a Focused Finite Amplitude Sound Beam Incident on a Curved Interface

    Science.gov (United States)

    Makin, Inder Raj Singh

    Reflection and transmission of a finite amplitude focused sound beam at a weakly curved interface separating two fluid-like media are investigated. The KZK parabolic wave equation, which accounts for thermoviscous absorption, diffraction, and nonlinearity, is used to describe the high intensity focused beam. The first part of the work deals with the quasilinear analysis of a weakly nonlinear beam after its reflection and transmission from a curved interface. A Green's function approach is used to define the field integrals describing the primary and the nonlinearly generated second harmonic beam. Closed-form solutions are obtained for the primary and second harmonic beams when a Gaussian amplitude distribution at the source is assumed. The second part of the research uses a numerical frequency domain solution of the KZK equation for a fully nonlinear analysis of the reflected and transmitted fields. Both piston and Gaussian sources are considered. Harmonic components generated in the medium due to propagation of the focused beam are evaluated, and formation of shocks in the reflected and transmitted beams is investigated. A finite amplitude focused beam is observed to be modified due to reflection and transmission from a curved interface in a manner distinct from that in the case of a small signal beam. Propagation curves, beam patterns, phase plots and time waveforms for various parameters defining the source and media pairs are presented, highlighting the effect of the interface curvature on the reflected and transmitted beams. Relevance of the current work to biomedical applications of ultrasound is discussed.

  15. Acoustical characteristic predictions of a multi-layer system of a submerged vehicle hull mounted sonar simplified to an infinite planar model

    Directory of Open Access Journals (Sweden)

    Sung-Hee Kim

    2012-06-01

    Full Text Available Hull Mounted Sonar (HMS is a long range submerged vehicle's hull-mounted passive sonar system which detects low-frequency noise caused by machineries of enemy ships or submerged vehicles. The HMS needs a sound absorption /insulation multi-layer structure to shut out the self-noise from own machineries and to amplify signals from outside. Therefore, acoustic analysis of the multi-layer system should be performed when the HMS is designed. This paper simplified the HMS multi-layer system to be an infinite planar multi-layer model. Also, main excitations that influence the HMS were classified into mechanical, plane wave and turbulent flow excitation, and the investigations for each excitation were performed for various models. Stiffened multi-layer analysis for mechanical excitation and general multi-layer analysis for turbulent flow excitation were developed. The infinite planar multi-layer analysis was expected to be more useful for preliminary design stage of HMS system than the infinite cylindrical model because of short analysis time and easiness of parameter study.

  16. Selection of a Suitable Wall Pressure Spectrum Model for Estimating Flow-Induced Noise in Sonar Applications

    Directory of Open Access Journals (Sweden)

    V. Bhujanga Rao

    1995-01-01

    Full Text Available Flow-induced structural noise of a sonar dome in which the sonar transducer is housed, constitutes a major source of self-noise above a certain speed of the vessel. Excitation of the sonar dome structure by random pressure fluctuations in turbulent boundary layer flow leads to acoustic radiation into the interior of the dome. This acoustic radiation is termed flow-induced structural noise. Such noise contributes significantly to sonar self-noise of submerged vessels cruising at high speed and plays an important role in surface ships, torpedos, and towed sonars as well. Various turbulent boundary layer wall pressure models published were analyzed and the most suitable analytical model for the sonar dome application selected while taking into account high frequency, fluid loading, low wave number contribution, and pressure gradient effects. These investigations included type of coupling that exists between turbulent boundary layer pressure fluctuations and dome wall structure of a typical sonar dome. Comparison of theoretical data with measured data onboard a ship are also reported.

  17. Mid-Frequency Sonar Interactions with Beaked Whales

    National Research Council Canada - National Science Library

    Foote, Kenneth G; Feijoo, Gonzalo R; Rye, Kent; Reidenberg, Joy; Hastings, Mardi

    2007-01-01

    The top-level goal of this project is to build an interactive online modeling and visualization system, called the Virtual Beaked Whale, to enable users to predict mid-frequency sonar-induced acoustic...

  18. A novel approach to surveying sturgeon using side-scan sonar and occupancy modeling

    Science.gov (United States)

    Flowers, H. Jared; Hightower, Joseph E.

    2013-01-01

    Technological advances represent opportunities to enhance and supplement traditional fisheries sampling approaches. One example with growing importance for fisheries research is hydroacoustic technologies such as side-scan sonar. Advantages of side-scan sonar over traditional techniques include the ability to sample large areas efficiently and the potential to survey fish without physical handling-important for species of conservation concern, such as endangered sturgeons. Our objectives were to design an efficient survey methodology for sampling Atlantic Sturgeon Acipenser oxyrinchus by using side-scan sonar and to developmethods for analyzing these data. In North Carolina and South Carolina, we surveyed six rivers thought to contain varying abundances of sturgeon by using a combination of side-scan sonar, telemetry, and video cameras (i.e., to sample jumping sturgeon). Lower reaches of each river near the saltwater-freshwater interface were surveyed on three occasions (generally successive days), and we used occupancy modeling to analyze these data.We were able to detect sturgeon in five of six rivers by using these methods. Side-scan sonar was effective in detecting sturgeon, with estimated gear-specific detection probabilities ranging from 0.2 to 0.5 and river-specific occupancy estimates (per 2-km river segment) ranging from 0.0 to 0.8. Future extensions of this occupancy modeling framework will involve the use of side-scan sonar data to assess sturgeon habitat and abundance in different river systems.

  19. Making sound vortices by metasurfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Liping; Qiu, Chunyin, E-mail: cyqiu@whu.edu.cn; Lu, Jiuyang; Tang, Kun; Ke, Manzhu; Peng, Shasha [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Jia, Han [State Key Laboratory of Acoustics and Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190 (China); Liu, Zhengyou [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Institute for Advanced Studies, Wuhan University, Wuhan 430072 (China)

    2016-08-15

    Based on the Huygens-Fresnel principle, a metasurface structure is designed to generate a sound vortex beam in airborne environment. The metasurface is constructed by a thin planar plate perforated with a circular array of deep subwavelength resonators with desired phase and amplitude responses. The metasurface approach in making sound vortices is validated well by full-wave simulations and experimental measurements. Potential applications of such artificial spiral beams can be anticipated, as exemplified experimentally by the torque effect exerting on an absorbing disk.

  20. Light and Sound

    CERN Document Server

    Karam, P Andrew

    2010-01-01

    Our world is largely defined by what we see and hear-but our uses for light and sound go far beyond simply seeing a photo or hearing a song. A concentrated beam of light, lasers are powerful tools used in industry, research, and medicine, as well as in everyday electronics like DVD and CD players. Ultrasound, sound emitted at a high frequency, helps create images of a developing baby, cleans teeth, and much more. Light and Sound teaches how light and sound work, how they are used in our day-to-day lives, and how they can be used to learn about the universe at large.

  1. An integrated environment for fast development and performance assessment of sonar image processing algorithms - SSIE

    DEFF Research Database (Denmark)

    Henriksen, Lars

    1996-01-01

    The sonar simulator integrated environment (SSIE) is a tool for developing high performance processing algorithms for single or sequences of sonar images. The tool is based on MATLAB providing a very short lead time from concept to executable code and thereby assessment of the algorithms tested...... of the algorithms is the availability of sonar images. To accommodate this problem the SSIE has been equipped with a simulator capable of generating high fidelity sonar images for a given scene of objects, sea-bed AUV path, etc. In the paper the main components of the SSIE is described and examples of different...... processing steps are given...

  2. A novel underwater dam crack detection and classification approach based on sonar images.

    Science.gov (United States)

    Shi, Pengfei; Fan, Xinnan; Ni, Jianjun; Khan, Zubair; Li, Min

    2017-01-01

    Underwater dam crack detection and classification based on sonar images is a challenging task because underwater environments are complex and because cracks are quite random and diverse in nature. Furthermore, obtainable sonar images are of low resolution. To address these problems, a novel underwater dam crack detection and classification approach based on sonar imagery is proposed. First, the sonar images are divided into image blocks. Second, a clustering analysis of a 3-D feature space is used to obtain the crack fragments. Third, the crack fragments are connected using an improved tensor voting method. Fourth, a minimum spanning tree is used to obtain the crack curve. Finally, an improved evidence theory combined with fuzzy rule reasoning is proposed to classify the cracks. Experimental results show that the proposed approach is able to detect underwater dam cracks and classify them accurately and effectively under complex underwater environments.

  3. A novel underwater dam crack detection and classification approach based on sonar images.

    Directory of Open Access Journals (Sweden)

    Pengfei Shi

    Full Text Available Underwater dam crack detection and classification based on sonar images is a challenging task because underwater environments are complex and because cracks are quite random and diverse in nature. Furthermore, obtainable sonar images are of low resolution. To address these problems, a novel underwater dam crack detection and classification approach based on sonar imagery is proposed. First, the sonar images are divided into image blocks. Second, a clustering analysis of a 3-D feature space is used to obtain the crack fragments. Third, the crack fragments are connected using an improved tensor voting method. Fourth, a minimum spanning tree is used to obtain the crack curve. Finally, an improved evidence theory combined with fuzzy rule reasoning is proposed to classify the cracks. Experimental results show that the proposed approach is able to detect underwater dam cracks and classify them accurately and effectively under complex underwater environments.

  4. Sound radiation contrast in MR phase images. Method for the representation of elasticity, sound damping, and sound impedance changes

    International Nuclear Information System (INIS)

    Radicke, Marcus

    2009-01-01

    The method presented in this thesis combines ultrasound techniques with the magnetic-resonance tomography (MRT). An ultrasonic wave generates in absorbing media a static force in sound-propagation direction. The force leads at sound intensities of some W/cm 2 and a sound frequency in the lower MHz range to a tissue shift in the micrometer range. This tissue shift depends on the sound power, the sound frequency, the sound absorption, and the elastic properties of the tissue. A MRT sequence of the Siemens Healthcare AG was modified so that it measures (indirectly) the tissue shift, codes as grey values, and presents as 2D picture. By means of the grey values the sound-beam slope in the tissue can be visualized, and so additionally sound obstacles (changes of the sound impedance) can be detected. By the MRT images token up spatial changes of the tissue parameters sound absorption and elasticity can be detected. In this thesis measurements are presented, which show the feasibility and future chances of this method especially for the mammary-cancer diagnostics. [de

  5. Probability-Based Recognition Framework for Underwater Landmarks Using Sonar Images †.

    Science.gov (United States)

    Lee, Yeongjun; Choi, Jinwoo; Ko, Nak Yong; Choi, Hyun-Taek

    2017-08-24

    This paper proposes a probability-based framework for recognizing underwater landmarks using sonar images. Current recognition methods use a single image, which does not provide reliable results because of weaknesses of the sonar image such as unstable acoustic source, many speckle noises, low resolution images, single channel image, and so on. However, using consecutive sonar images, if the status-i.e., the existence and identity (or name)-of an object is continuously evaluated by a stochastic method, the result of the recognition method is available for calculating the uncertainty, and it is more suitable for various applications. Our proposed framework consists of three steps: (1) candidate selection, (2) continuity evaluation, and (3) Bayesian feature estimation. Two probability methods-particle filtering and Bayesian feature estimation-are used to repeatedly estimate the continuity and feature of objects in consecutive images. Thus, the status of the object is repeatedly predicted and updated by a stochastic method. Furthermore, we develop an artificial landmark to increase detectability by an imaging sonar, which we apply to the characteristics of acoustic waves, such as instability and reflection depending on the roughness of the reflector surface. The proposed method is verified by conducting basin experiments, and the results are presented.

  6. Real-time underwater object detection based on an electrically scanned high-resolution sonar

    DEFF Research Database (Denmark)

    Henriksen, Lars

    1994-01-01

    The paper describes an approach to real time detection and tracking of underwater objects, using image sequences from an electrically scanned high-resolution sonar. The use of a high resolution sonar provides a good estimate of the location of the objects, but strains the computers on board, beca...

  7. Effects of Internal Waves on Sound Propagation in the Shallow Waters of the Continental Shelves

    Science.gov (United States)

    2016-09-01

    resolves to f > 375 Hz . A frequency of 2 kHz, which is around the frequency range of a mid-frequency sonar, was used for the study and is well above...the 375 Hz threshold. 2. Gaussian Beam Option Ray trace models are unable to approximate the effects of caustics, which are regions of intense

  8. HULU SUNGAI PERAK BED SEDIMENT MAPPING USING UNDERWATER ACOUSTIC SONAR

    Directory of Open Access Journals (Sweden)

    N. Arriafdi

    2016-09-01

    Full Text Available Development in acoustic survey techniques in particular side scan sonar have revolutionized the way we are able to image, map and understand the riverbed environment. It is now cost effective to image large areas of the riverbed using these techniques and the backscatter image created from surveys provides base line data from which thematic maps of the riverbed environment including maps of morphological geology, can be derived when interpreted in conjunction with in situ sampling data. This article focuses on investigation characteristics of sediments and correlation of side scan backscatter image with signal strength. The interpretation of acoustic backscatter rely on experienced interpretation by eye of grey scale images produced from the data. A 990F Starfish Side Scan Sonar was used to collect and develop a series of sonar images along 6 km of Hulu Sungai Perak. Background sediments could be delineated accurately and the image textures could be linked to the actual river floor appearance through grab sampling. A major difference was found in the acoustic returns from the two research area studies: the upstream area shows much rougher textures. This is due to an actual differences in riverbed roughness, caused by a difference in bottom currents and sediment dynamics in the two areas. The highest backscatter correlates with coarsest and roughness sediment. Result suggest that image based backscatter classification shows considerable promise for interpretation of side scan sonar data for the production of geological maps.

  9. Textural Segmentation of High-Resolution Sidescan Sonar Images

    National Research Council Canada - National Science Library

    Kalcic, Maria; Bibee, Dale

    1995-01-01

    .... The high resolution of the 455 kHz sonar imagery also provides much information about the surficial bottom sediments, however their acoustic scattering properties are not well understood at high frequencies...

  10. Recent Developments in SOBEK Passive Sonar Technology

    NARCIS (Netherlands)

    Hunter, A.J.; Fillinger, L.; Zampolli, M.; Clarijs, M.C.

    2012-01-01

    Surveillance of waterside locations for protection against threats from small fast surface vessels and underwater intruders is a very relevant but challenging problem. For this reason, the Netherlands Organisation for Applied Scientific Research (TNO) is developing SOBEK – a family of passive sonar

  11. Sensor Fusion - Sonar and Stereo Vision, Using Occupancy Grids and SIFT

    DEFF Research Database (Denmark)

    Plascencia, Alfredo; Bendtsen, Jan Dimon

    2006-01-01

    to the occupied and empty regions. SIFT (Scale Invariant Feature Transform) feature descriptors are  interpreted using gaussian probabilistic error models. The use of occupancy grids is proposed for representing the sonar  as well as the features descriptors readings. The Bayesian estimation approach is applied...... to update the sonar and the SIFT descriptors' uncertainty grids. The sensor fusion yields a significant reduction in the uncertainty of the occupancy grid compared to the individual sensor readings....

  12. Development of Discrete Power Supply with Charge Pump Method for High Powered Sonar System

    Directory of Open Access Journals (Sweden)

    Kristian Ismail

    2012-07-01

    Full Text Available Power supply is one of the electronic devices that can provide electric energy for electronic systems or other systems. There are several types of power supplies that can be applied depend on the requirement and functions. One example is the use of power supply for sonar systems. Sonar system is a device which can be used to detect a target under water. The sonar system is an electronic circuit that requires a power supply with specific characteristics when the sonar functions as a transmitter and a receiver in the specific span time (when on and the specific lag time (when off. This paper discusses the design of power supply for high-powered sonar systems with discrete methods in which high power supply is only applied when the acoustic waves radiated under water. Charge pump was used to get the appropriate output voltage from lower input voltage. Charge pump utilized a combination of series and parallel connections of capacitors. The working mode of this power supply used the lag time as the calculation of time to charge charge pump capacitors in parallel while the span time was used for the calculation of discharging the charge pump capacitors in series.

  13. Biologically-inspired radar and sonar lessons from nature

    CERN Document Server

    Balleri, Alessio; Baker, Chris

    2017-01-01

    This book presents some of the recent work that has been carried out to investigate how sophisticated sensing techniques used in nature can be applied to radar and sonar systems to improve their performance.

  14. SONAR: A High-Throughput Pipeline for Inferring Antibody Ontogenies from Longitudinal Sequencing of B Cell Transcripts.

    Science.gov (United States)

    Schramm, Chaim A; Sheng, Zizhang; Zhang, Zhenhai; Mascola, John R; Kwong, Peter D; Shapiro, Lawrence

    2016-01-01

    The rapid advance of massively parallel or next-generation sequencing technologies has made possible the characterization of B cell receptor repertoires in ever greater detail, and these developments have triggered a proliferation of software tools for processing and annotating these data. Of especial interest, however, is the capability to track the development of specific antibody lineages across time, which remains beyond the scope of most current programs. We have previously reported on the use of techniques such as inter- and intradonor analysis and CDR3 tracing to identify transcripts related to an antibody of interest. Here, we present Software for the Ontogenic aNalysis of Antibody Repertoires (SONAR), capable of automating both general repertoire analysis and specialized techniques for investigating specific lineages. SONAR annotates next-generation sequencing data, identifies transcripts in a lineage of interest, and tracks lineage development across multiple time points. SONAR also generates figures, such as identity-divergence plots and longitudinal phylogenetic "birthday" trees, and provides interfaces to other programs such as DNAML and BEAST. SONAR can be downloaded as a ready-to-run Docker image or manually installed on a local machine. In the latter case, it can also be configured to take advantage of a high-performance computing cluster for the most computationally intensive steps, if available. In summary, this software provides a useful new tool for the processing of large next-generation sequencing datasets and the ontogenic analysis of neutralizing antibody lineages. SONAR can be found at https://github.com/scharch/SONAR, and the Docker image can be obtained from https://hub.docker.com/r/scharch/sonar/.

  15. Side-Scan-Sonar Lines for Hudson River, NY

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Side Scan Sonar and Subbottom Profiler Tracklines. Data was collected November 5 to December 15, 2009, in the estuary north from Saugerties to Troy. Fugro utilized...

  16. Bathymetry mapping using a GPS-sonar equipped remote control boat: Application in waste stabilisation ponds

    Science.gov (United States)

    Coggins, Liah; Ghadouani, Anas; Ghisalberti, Marco

    2014-05-01

    Traditionally, bathymetry mapping of ponds, lakes and rivers have used techniques which are low in spatial resolution, sometimes subjective in terms of precision and accuracy, labour intensive, and that require a high level of safety precautions. In waste stabilisation ponds (WSP) in particular, sludge heights, and thus sludge volume, are commonly measured using a sludge judge (a clear plastic pipe with length markings). A remote control boat fitted with a GPS-equipped sonar unit can improve the resolution of depth measurements, and reduce safety and labour requirements. Sonar devices equipped with GPS technology, also known as fish finders, are readily available and widely used by people in boating. Through the use of GPS technology in conjunction with sonar, the location and depth can be recorded electronically onto a memory card. However, despite its high applicability to the field, this technology has so far been underutilised. In the case of WSP, the sonar can measure the water depth to the top of the sludge layer, which can then be used to develop contour maps of sludge distribution and to determine sludge volume. The coupling of sonar technology with a remotely operative vehicle has several advantages of traditional measurement techniques, particularly in removing human subjectivity of readings, and the sonar being able to collect more data points in a shorter period of time, and continuously, with a much higher spatial resolution. The GPS-sonar equipped remote control boat has been tested on in excess of 50 WSP within Western Australia, and has shown a very strong correlation (R2 = 0.98) between spot readings taken with the sonar compared to a sludge judge. This has shown that the remote control boat with GPS-sonar device is capable of providing sludge bathymetry with greatly increased spatial resolution, while greatly reducing profiling time. Remotely operated vehicles, such as the one built in this study, are useful for not only determining sludge

  17. PMHT Approach for Multi-Target Multi-Sensor Sonar Tracking in Clutter.

    Science.gov (United States)

    Li, Xiaohua; Li, Yaan; Yu, Jing; Chen, Xiao; Dai, Miao

    2015-11-06

    Multi-sensor sonar tracking has many advantages, such as the potential to reduce the overall measurement uncertainty and the possibility to hide the receiver. However, the use of multi-target multi-sensor sonar tracking is challenging because of the complexity of the underwater environment, especially the low target detection probability and extremely large number of false alarms caused by reverberation. In this work, to solve the problem of multi-target multi-sensor sonar tracking in the presence of clutter, a novel probabilistic multi-hypothesis tracker (PMHT) approach based on the extended Kalman filter (EKF) and unscented Kalman filter (UKF) is proposed. The PMHT can efficiently handle the unknown measurements-to-targets and measurements-to-transmitters data association ambiguity. The EKF and UKF are used to deal with the high degree of nonlinearity in the measurement model. The simulation results show that the proposed algorithm can improve the target tracking performance in a cluttered environment greatly, and its computational load is low.

  18. Improving Protection Agains Intruders Using Passive Sonar

    NARCIS (Netherlands)

    Fillinger, L.; Hunter, A.J.; Zampolli, M.; Clarijs, M.C.; Verolme, J.L.

    2011-01-01

    Divers and small vessels are increasingly recognized as a potential threat to high value assets. Harbour and waterside surveillance systems that are used to counter the threat of divers are usually based on active sonar, whose performance can be limited by reverberation in a harbour environment.

  19. Groups of bats improve sonar efficiency through mutual suppression of pulse emissions.

    Directory of Open Access Journals (Sweden)

    Jenna eJarvis

    2013-06-01

    Full Text Available How bats adapt their sonar behavior to accommodate the noisiness of a crowded day roost is a mystery. Some bats change their pulse acoustics to enhance the distinction between theirs and another bat’s echoes, but additional mechanisms are needed to explain the bat sonar system’s exceptional resilience to jamming by conspecifics. Variable pulse repetition rate strategies offer one potential solution to this dynamic problem, but precisely how changes in pulse rate could improve sonar performance in social settings is unclear. Here we show that bats decrease their emission rates as population density increases, following a pattern that reflects a cumulative mutual suppression of each other’s pulse emissions. Playback of artificially-generated echolocation pulses similarly slowed emission rates, demonstrating that suppression was mediated by hearing the pulses of other bats. Slower emission rates did not support an antiphonal emission strategy but did reduce the relative proportion of emitted pulses that overlapped with another bat’s emissions, reducing the relative rate of mutual interference. The prevalence of acoustic interferences occurring amongst bats was empirically determined to be a linear function of population density and mean emission rates. Consequently as group size increased, small reductions in emission rates spread across the group partially mitigated the increase in interference rate. Drawing on lessons learned from communications networking theory we show how modest decreases in pulse emission rates can significantly increase the net information throughput of the shared acoustic space, thereby improving sonar efficiency for all individuals in a group. We propose that an automated acoustic suppression of pulse emissions triggered by bats hearing each other's emissions dynamically optimizes sonar efficiency for the entire group.

  20. Automated detection of submerged navigational obstructions in freshwater impoundments with hull mounted sidescan sonar

    Science.gov (United States)

    Morris, Phillip A.

    The prevalence of low-cost side scanning sonar systems mounted on small recreational vessels has created improved opportunities to identify and map submerged navigational hazards in freshwater impoundments. However, these economical sensors also present unique challenges for automated techniques. This research explores related literature in automated sonar imagery processing and mapping technology, proposes and implements a framework derived from these sources, and evaluates the approach with video collected from a recreational grade sonar system. Image analysis techniques including optical character recognition and an unsupervised computer automated detection (CAD) algorithm are employed to extract the transducer GPS coordinates and slant range distance of objects protruding from the lake bottom. The retrieved information is formatted for inclusion into a spatial mapping model. Specific attributes of the sonar sensors are modeled such that probability profiles may be projected onto a three dimensional gridded map. These profiles are computed from multiple points of view as sonar traces crisscross or come near each other. As lake levels fluctuate over time so do the elevation points of view. With each sonar record, the probability of a hazard existing at certain elevations at the respective grid points is updated with Bayesian mechanics. As reinforcing data is collected, the confidence of the map improves. Given a lake's current elevation and a vessel draft, a final generated map can identify areas of the lake that have a high probability of containing hazards that threaten navigation. The approach is implemented in C/C++ utilizing OpenCV, Tesseract OCR, and QGIS open source software and evaluated in a designated test area at Lake Lavon, Collin County, Texas.

  1. Modulation, resolution and signal processing in radar, sonar and related systems

    CERN Document Server

    Benjamin, R; Costrell, L

    1966-01-01

    Electronics and Instrumentation, Volume 35: Modulation, Resolution and Signal Processing in Radar, Sonar and Related Systems presents the practical limitations and potentialities of advanced modulation systems. This book discusses the concepts and techniques in the radar context, but they are equally essential to sonar and to a wide range of signaling and data-processing applications, including seismology, radio astronomy, and band-spread communications.Organized into 15 chapters, this volume begins with an overview of the principal developments sought in pulse radar. This text then provides a

  2. Sonar Headphone Selection for Optimum Performance: An Overview

    National Research Council Canada - National Science Library

    Russotti, Joseph

    1995-01-01

    .... The advantages and disadvantages of open and sealed circumaural headsets and recent developments in noise canceling headsets are discussed, along with the possibility of reducing noise levels in sonar spaces to permit use of higher fidelity headphone designs.

  3. SONAR: A high-throughput pipeline for inferring antibody ontogenies from longitudinal sequencing of B cell transcripts

    Directory of Open Access Journals (Sweden)

    Chaim A Schramm

    2016-09-01

    Full Text Available The rapid advance of massively parallel or next-generation sequencing technologies has made possible the characterization of B cell receptor repertoires in ever greater detail, leading to a proliferation of software tools for processing and annotating this data. Of especial interest, however, is the capability to track the development of specific antibody lineages across time, which remains beyond the scope of most current programs. We have previously reported on the use of techniques such as inter- and intra-donor analysis and CDR3 tracing to identify transcripts related to an antibody of interest. Here, we present Software for the Ontogenic aNalysis of Antibody Repertoires (SONAR, capable of automating both general repertoire analysis and specialized techniques for investigating specific lineages. SONAR annotates next-generation sequencing data, identifies transcripts in a lineage of interest, and tracks lineage development across multiple time points. SONAR also generates figures, such as identity-divergence plots and longitudinal phylogenetic birthday trees, and provides interfaces to other programs such as DNAML and BEAST. SONAR can be downloaded as a ready-to-run Docker image or manually installed on a local machine. In the latter case, it can also be configured to take advantage of a high-performance computing cluster for the most computationally intensive steps, if available. In summary, this software provides a useful new tool for the processing of large next-generation sequencing datasets and the ontogenic analysis of neutralizing antibody lineages. SONAR can be found at https://github.com/scharch/SONAR and the Docker image can be obtained from https://hub.docker.com/r/scharch/sonar/.

  4. Correlation Based Testing for Passive Sonar Picture Rationalization

    National Research Council Canada - National Science Library

    Mellema, Garfield R

    2007-01-01

    .... The sample correlation coefficient, is a statistical measure of relatedness. This paper describes the application of a test based on that measure to compare tracks produced by a probabilistic data association filter from a set of towed array sonar data. Keywords.

  5. Thermal management of thermoacoustic sound projectors using a free-standing carbon nanotube aerogel sheet as a heat source.

    Science.gov (United States)

    Aliev, Ali E; Mayo, Nathanael K; Baughman, Ray H; Avirovik, Dragan; Priya, Shashank; Zarnetske, Michael R; Blottman, John B

    2014-10-10

    Carbon nanotube (CNT) aerogel sheets produce smooth-spectra sound over a wide frequency range (1-10(5) Hz) by means of thermoacoustic (TA) sound generation. Protective encapsulation of CNT sheets in inert gases between rigid vibrating plates provides resonant features for the TA sound projector and attractive performance at needed low frequencies. Energy conversion efficiencies in air of 2% and 10% underwater, which can be enhanced by further increasing the modulation temperature. Using a developed method for accurate temperature measurements for the thin aerogel CNT sheets, heat dissipation processes, failure mechanisms, and associated power densities are investigated for encapsulated multilayered CNT TA heaters and related to the thermal diffusivity distance when sheet layers are separated. Resulting thermal management methods for high applied power are discussed and deployed to construct efficient and tunable underwater sound projector for operation at relatively low frequencies, 10 Hz-10 kHz. The optimal design of these TA projectors for high-power SONAR arrays is discussed.

  6. Thermal management of thermoacoustic sound projectors using a free-standing carbon nanotube aerogel sheet as a heat source

    International Nuclear Information System (INIS)

    Aliev, Ali E; Mayo, Nathanael K; Baughman, Ray H; Avirovik, Dragan; Priya, Shashank; Zarnetske, Michael R; Blottman, John B

    2014-01-01

    Carbon nanotube (CNT) aerogel sheets produce smooth-spectra sound over a wide frequency range (1–10 5 Hz) by means of thermoacoustic (TA) sound generation. Protective encapsulation of CNT sheets in inert gases between rigid vibrating plates provides resonant features for the TA sound projector and attractive performance at needed low frequencies. Energy conversion efficiencies in air of 2% and 10% underwater, which can be enhanced by further increasing the modulation temperature. Using a developed method for accurate temperature measurements for the thin aerogel CNT sheets, heat dissipation processes, failure mechanisms, and associated power densities are investigated for encapsulated multilayered CNT TA heaters and related to the thermal diffusivity distance when sheet layers are separated. Resulting thermal management methods for high applied power are discussed and deployed to construct efficient and tunable underwater sound projector for operation at relatively low frequencies, 10 Hz–10 kHz. The optimal design of these TA projectors for high-power SONAR arrays is discussed. (paper)

  7. Sound beam manipulation based on temperature gradients

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Feng [Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China); School of Physics & Electronic Engineering, Changshu Institute of Technology, Changshu 215500 (China); Quan, Li; Liu, Xiaozhou, E-mail: xzliu@nju.edu.cn; Gong, Xiufen [Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)

    2015-10-28

    Previous research with temperature gradients has shown the feasibility of controlling airborne sound propagation. Here, we present a temperature gradients based airborne sound manipulation schemes: a cylindrical acoustic omnidirectional absorber (AOA). The proposed AOA has high absorption performance which can almost completely absorb the incident wave. Geometric acoustics is used to obtain the refractive index distributions with different radii, which is then utilized to deduce the desired temperature gradients. Since resonant units are not applied in the scheme, its working bandwidth is expected to be broadband. The scheme is temperature-tuned and easy to realize, which is of potential interest to fields such as noise control or acoustic cloaking.

  8. Behavioral Response of Reef Fish and Green Sea Turtles to Midfrequency Sonar.

    Science.gov (United States)

    Watwood, Stephanie L; Iafrate, Joseph D; Reyier, Eric A; Redfoot, William E

    2016-01-01

    There is growing concern over the potential effects of high-intensity sonar on wild fish populations and commercial fisheries. Acoustic telemetry was employed to measure the movements of free-ranging reef fish and sea turtles in Port Canaveral, FL, in response to routine submarine sonar testing. Twenty-five sheepshead (Archosargus probatocephalus), 28 gray snapper (Lutjanus griseus), and 29 green sea turtles (Chelonia mydas) were tagged, with movements monitored for a period of up to 4 months using an array of passive acoustic receivers. Baseline residency was examined for fish and sea turtles before, during, and after the test event. No mortality of tagged fish or sea turtles was evident from the sonar test event. There was a significant increase in the daily residency index for both sheepshead and gray snapper at the testing wharf subsequent to the event. No broad-scale movement from the study site was observed during or immediately after the test.

  9. Adaptive Port-Starboard Beamforming of Triplet Sonar Arrays

    NARCIS (Netherlands)

    Groen, J.; Beerens, S.P.; Been, R.; Doisy, Y.

    2005-01-01

    Abstract—For a low-frequency active sonar (LFAS) with a triplet receiver array, it is not clear in advance which signal processing techniques optimize its performance. Here, several advanced beamformers are analyzed theoretically, and the results are compared to experimental data obtained in sea

  10. MSPOT a performance optimisation tool for ASW sonar

    NARCIS (Netherlands)

    Beerens, S.P.; Benders, F.P.A.

    2012-01-01

    Several navies are operating or procuring low-frequency active sonar systems (LFAS) as the primary part of their ASW capability. Since LFAS is a relatively new sensor with a performance strongly depending on environmental conditions, the proper operational sensor settings, such as depth and pulse

  11. Sonar Image Enhancements for Improved Detection of Sea Mines

    DEFF Research Database (Denmark)

    Jespersen, Karl; Sørensen, Helge Bjarup Dissing; Zerr, Benoit

    1999-01-01

    In this paper, five methods for enhancing sonar images prior to automatic detection of sea mines are investigated. Two of the methods have previously been published in connection with detection systems and serve as reference. The three new enhancement approaches are variance stabilizing log...... transform, nonlinear filtering, and pixel averaging for speckle reduction. The effect of the enhancement step is tested by using the full prcessing chain i.e. enhancement, detection and thresholding to determine the number of detections and false alarms. Substituting different enhancement algorithms...... in the processing chain gives a precise measure of the performance of the enhancement stage. The test is performed using a sonar image database with images ranging from very simple to very complex. The result of the comparison indicates that the new enhancement approaches improve the detection performance....

  12. Applying multibeam sonar and mathematical modeling for mapping seabed substrate and biota of offshore shallows

    Science.gov (United States)

    Herkül, Kristjan; Peterson, Anneliis; Paekivi, Sander

    2017-06-01

    Both basic science and marine spatial planning are in a need of high resolution spatially continuous data on seabed habitats and biota. As conventional point-wise sampling is unable to cover large spatial extents in high detail, it must be supplemented with remote sensing and modeling in order to fulfill the scientific and management needs. The combined use of in situ sampling, sonar scanning, and mathematical modeling is becoming the main method for mapping both abiotic and biotic seabed features. Further development and testing of the methods in varying locations and environmental settings is essential for moving towards unified and generally accepted methodology. To fill the relevant research gap in the Baltic Sea, we used multibeam sonar and mathematical modeling methods - generalized additive models (GAM) and random forest (RF) - together with underwater video to map seabed substrate and epibenthos of offshore shallows. In addition to testing the general applicability of the proposed complex of techniques, the predictive power of different sonar-based variables and modeling algorithms were tested. Mean depth, followed by mean backscatter, were the most influential variables in most of the models. Generally, mean values of sonar-based variables had higher predictive power than their standard deviations. The predictive accuracy of RF was higher than that of GAM. To conclude, we found the method to be feasible and with predictive accuracy similar to previous studies of sonar-based mapping.

  13. Surficial geology of the sea floor in Long Island Sound offshore of Plum Island, New York

    Science.gov (United States)

    McMullen, K.Y.; Poppe, L.J.; Danforth, W.W.; Blackwood, D.S.; Schaer, J.D.; Ostapenko, A.J.; Glomb, K.A.; Doran, E.F.

    2010-01-01

    The U.S. Geological Survey (USGS), the Connecticut Department of Environmental Protection, and the National Oceanic and Atmospheric Administration (NOAA) have been working cooperatively to interpret surficial sea-floor geology along the coast of the Northeastern United States. NOAA survey H11445 in eastern Long Island Sound, offshore of Plum Island, New York, covers an area of about 12 square kilometers. Multibeam bathymetry and sidescan-sonar imagery from the survey, as well as sediment and photographic data from 13 stations occupied during a USGS verification cruise are used to delineate sea-floor features and characterize the environment. Bathymetry gradually deepens offshore to over 100 meters in a depression in the northwest part of the study area and reaches 60 meters in Plum Gut, a channel between Plum Island and Orient Point. Sand waves are present on a shoal north of Plum Island and in several smaller areas around the basin. Sand-wave asymmetry indicates that counter-clockwise net sediment transport maintains the shoal. Sand is prevalent where there is low backscatter in the sidescan-sonar imagery. Gravel and boulder areas are submerged lag deposits produced from the Harbor Hill-Orient Point-Fishers Island moraine segment and are found adjacent to the shorelines and just north of Plum Island, where high backscatter is present in the sidescan-sonar imagery.

  14. Second harmonic sound field after insertion of a biological tissue sample

    Science.gov (United States)

    Zhang, Dong; Gong, Xiu-Fen; Zhang, Bo

    2002-01-01

    Second harmonic sound field after inserting a biological tissue sample is investigated by theory and experiment. The sample is inserted perpendicular to the sound axis, whose acoustical properties are different from those of surrounding medium (distilled water). By using the superposition of Gaussian beams and the KZK equation in quasilinear and parabolic approximations, the second harmonic field after insertion of the sample can be derived analytically and expressed as a linear combination of self- and cross-interaction of the Gaussian beams. Egg white, egg yolk, porcine liver, and porcine fat are used as the samples and inserted in the sound field radiated from a 2 MHz uniformly excited focusing source. Axial normalized sound pressure curves of the second harmonic wave before and after inserting the sample are measured and compared with the theoretical results calculated with 10 items of Gaussian beam functions.

  15. On the environmental impact of continuous active sonar

    NARCIS (Netherlands)

    Vossen, R. van; Spek, E. van der; Dekeling, R.P.A.; Beerens, S.P.; Lam, F.P.A.; Benda Beckmann, A.M. von

    2013-01-01

    Continuous Active Sonar (CAS) is an emerging technology in anti-submarine warfare operations. The feasibility of the technology has been demonstrated and it has been shown that CAS has a potential to reduce false alarm rates in reverberation-limited conditions. Now that the feasibility has been

  16. Archaeological use of Synthetic Aperture Sonar on deepwater wreck sites in Skagerrak

    DEFF Research Database (Denmark)

    Maarleveld, Thijs J.; Ødegård, Øyvind; Hansen, Roy E.

    2018-01-01

    Marine archaeological surveying in deep waters has so far been challenging, mainly due to operational and technological constraints. The standard tool has been Side Scan Sonar (SSS) towed behind a surface vessel. Synthetic Aperture Sonar (SAS) technology is not subject to the traditional range....../resolution tradeoff, and produces results of considerably higher quality than traditional SSS. In 2015 and 2016 a comprehensive mapping of wrecks in Skagerrak, a large deepwater area off the south coast of Norway was undertaken, using an interferometric SAS system deployed on an autonomous underwater vehicle...

  17. Contact-Level Multistatic Sonar Data Simulator for Tracker Performance Assessment

    National Research Council Canada - National Science Library

    Grimmett, Doug; Coraluppi, Stefano

    2006-01-01

    ...). A brief description of the simulation approach is given, which includes simple sonar equation modeling, resulting in sensor-to-sensor target fading effects, as well as contact localization modeling...

  18. 77 FR 52317 - Record of Decision for Surveillance Towed Array Sensor System Low Frequency Active Sonar

    Science.gov (United States)

    2012-08-29

    ... DEPARTMENT OF DEFENSE Department of the Navy Record of Decision for Surveillance Towed Array Sensor System Low Frequency Active Sonar AGENCY: Department of the Navy, DoD. ACTION: Notice of decision... to employ up to four Surveillance Towed Array Sensor System Low Frequency Active (SURTASS LFA) sonar...

  19. Enhanced echolocation via robust statistics and super-resolution of sonar images

    Science.gov (United States)

    Kim, Kio

    Echolocation is a process in which an animal uses acoustic signals to exchange information with environments. In a recent study, Neretti et al. have shown that the use of robust statistics can significantly improve the resiliency of echolocation against noise and enhance its accuracy by suppressing the development of sidelobes in the processing of an echo signal. In this research, the use of robust statistics is extended to problems in underwater explorations. The dissertation consists of two parts. Part I describes how robust statistics can enhance the identification of target objects, which in this case are cylindrical containers filled with four different liquids. Particularly, this work employs a variation of an existing robust estimator called an L-estimator, which was first suggested by Koenker and Bassett. As pointed out by Au et al.; a 'highlight interval' is an important feature, and it is closely related with many other important features that are known to be crucial for dolphin echolocation. A varied L-estimator described in this text is used to enhance the detection of highlight intervals, which eventually leads to a successful classification of echo signals. Part II extends the problem into 2 dimensions. Thanks to the advances in material and computer technology, various sonar imaging modalities are available on the market. By registering acoustic images from such video sequences, one can extract more information on the region of interest. Computer vision and image processing allowed application of robust statistics to the acoustic images produced by forward looking sonar systems, such as Dual-frequency Identification Sonar and ProViewer. The first use of robust statistics for sonar image enhancement in this text is in image registration. Random Sampling Consensus (RANSAC) is widely used for image registration. The registration algorithm using RANSAC is optimized for sonar image registration, and the performance is studied. The second use of robust

  20. Studies on a Spatialized Audio Interface for Sonar

    Science.gov (United States)

    2011-10-03

    addition of spatialized audio to visual displays for sonar is much akin to the development of talking movies in the early days of cinema and can be...than using the brute-force approach. PCA is one among several techniques that share similarities with the computational architecture of a

  1. Inversion of Side Scan Sonar Motion and Posture in Seabed Geomorphology

    Directory of Open Access Journals (Sweden)

    Tao Weiliang

    2017-08-01

    Full Text Available Side scan sonar measurement platform, affected by underwater environment and its own motion precision, inevitably has posture and motion disturbance, which greatly affects accuracy of geomorphic image formation. It is difficult to sensitively and accurately capture these underwater disturbances by relying on auxiliary navigation devices. In this paper, we propose a method to invert motion and posture information of the measurement platform by using the matching relation between the strip images. The inversion algorithm is the key link in the image mosaic frame of side scan sonar, and the acquired motion posture information can effectively improve seabed topography and plotting accuracy and stability. In this paper, we first analyze influence of platform motion and posture on side scan sonar mapping, and establish the correlation model between motion, posture information and strip image matching information. Then, based on the model, a reverse neural network is established. Based on input, output of neural network, design of and test data set, a motion posture inversion mechanism based on strip image matching information is established. Accuracy and validity of the algorithm are verified by the experimental results.

  2. Automatic classification techniques for type of sediment map from multibeam sonar data

    Science.gov (United States)

    Zakariya, R.; Abdullah, M. A.; Che Hasan, R.; Khalil, I.

    2018-02-01

    Sediment map can be important information for various applications such as oil drilling, environmental and pollution study. A study on sediment mapping was conducted at a natural reef (rock) in Pulau Payar using Sound Navigation and Ranging (SONAR) technology which is Multibeam Echosounder R2-Sonic. This study aims to determine sediment type by obtaining backscatter and bathymetry data from multibeam echosounder. Ground truth data were used to verify the classification produced. The method used to analyze ground truth samples consists of particle size analysis (PSA) and dry sieving methods. Different analysis being carried out due to different sizes of sediment sample obtained. The smaller size was analyzed using PSA with the brand CILAS while bigger size sediment was analyzed using sieve. For multibeam, data acquisition includes backscatter strength and bathymetry data were processed using QINSy, Qimera, and ArcGIS. This study shows the capability of multibeam data to differentiate the four types of sediments which are i) very coarse sand, ii) coarse sand, iii) very coarse silt and coarse silt. The accuracy was reported as 92.31% overall accuracy and 0.88 kappa coefficient.

  3. Boundary layer structure observed by Shipborne Doppler Sonar in the Suez Canal zone

    Energy Technology Data Exchange (ETDEWEB)

    Fiocco, G. (Rome Univ. (Italy). Ist. di Fisica); Mastrantonio, G.; Ricotta, A. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. per il Plasma nello Spazio)

    Observations of the boundary layer with a monostatic Sonar and other instrumentation were carried out in the Suez canal zone in January and March 1979, from the Italian m.v. Salernum on its way to and from a GARP assignment. The Sonar was operated almost continuously throughout the passages. In addition to the intensity records, an off-line Doppler analysis involving the use of the fast Fourier transform of the digitized Sonar echoes has provided the vertical component w of the velocity. In general, because of efficient filtering and of the good quality of the data, a vertical profile of w has been determined for each transmitted pulse. During a prolonged stay in the Bitter lakes vertical profiles of temperature and humidity were also obtained by deploying a tethered balloon. Large temporal and spatial temperature contrasts exist in the canal zone due to the presence of the desert and of large and small bodies of water. The ensuring phenomenology during the time of observation was quite varied.

  4. AWARE Sonar and Sperm Whale Tagging (DE9906, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The AWARE sonar and sperm whale tagging cruise primarily focuses on whales in the continental shelf areas, with the following objectives: 1) Develop a better...

  5. AWARE Sonar and Sperm Whale Tagging (DE0007, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The AWARE sonar and sperm whale tagging cruise primarily focuses on whales in the continental shelf areas, with the following objectives: 1) Develop a better...

  6. Sonar gas flux estimation by bubble insonification: application to methane bubble flux from seep areas in the outer Laptev Sea

    Science.gov (United States)

    Leifer, Ira; Chernykh, Denis; Shakhova, Natalia; Semiletov, Igor

    2017-06-01

    Sonar surveys provide an effective mechanism for mapping seabed methane flux emissions, with Arctic submerged permafrost seepage having great potential to significantly affect climate. We created in situ engineered bubble plumes from 40 m depth with fluxes spanning 0.019 to 1.1 L s-1 to derive the in situ calibration curve (Q(σ)). These nonlinear curves related flux (Q) to sonar return (σ) for a multibeam echosounder (MBES) and a single-beam echosounder (SBES) for a range of depths. The analysis demonstrated significant multiple bubble acoustic scattering - precluding the use of a theoretical approach to derive Q(σ) from the product of the bubble σ(r) and the bubble size distribution where r is bubble radius. The bubble plume σ occurrence probability distribution function (Ψ(σ)) with respect to Q found Ψ(σ) for weak σ well described by a power law that likely correlated with small-bubble dispersion and was strongly depth dependent. Ψ(σ) for strong σ was largely depth independent, consistent with bubble plume behavior where large bubbles in a plume remain in a focused core. Ψ(σ) was bimodal for all but the weakest plumes. Q(σ) was applied to sonar observations of natural arctic Laptev Sea seepage after accounting for volumetric change with numerical bubble plume simulations. Simulations addressed different depths and gases between calibration and seep plumes. Total mass fluxes (Qm) were 5.56, 42.73, and 4.88 mmol s-1 for MBES data with good to reasonable agreement (4-37 %) between the SBES and MBES systems. The seepage flux occurrence probability distribution function (Ψ(Q)) was bimodal, with weak Ψ(Q) in each seep area well described by a power law, suggesting primarily minor bubble plumes. The seepage-mapped spatial patterns suggested subsurface geologic control attributing methane fluxes to the current state of subsea permafrost.

  7. Side-Scan_Sonar backscatter tiles for Hudson River, NY (.xtf)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Raw XTF files. Sonar data were collected November 6 to December 15, 2009, in the estuary north from Saugerties to Troy. Data Collection and Processing: The...

  8. Assessing Sonar Performance in Realistic Environments

    Science.gov (United States)

    2012-10-01

    Her Majesty the Queen in Right of Canada (Department of National Defence), 2012 c© Sa Majesté la Reine en droit du Canada (Ministère de la Défense... Victoria Class submarine. Q316 included a number of objectives specific to the ASPIRE project. These included demonstrating the use of gliders for the... Victoria Class C3 Optimization’ for the high level architecture for synthetic environment simulations • 20EA05: ‘Support to CMS: Ruggedized Sonar Test

  9. Submarine Upward Looking Sonar Ice Draft Profile Data and Statistics

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of upward looking sonar draft data collected by submarines in the Arctic Ocean. It includes data from both U.S. Navy and Royal Navy...

  10. Propagation of Sound in a Bose-Einstein Condensate

    International Nuclear Information System (INIS)

    Andrews, M.R.; Kurn, D.M.; Miesner, H.; Durfee, D.S.; Townsend, C.G.; Inouye, S.; Ketterle, W.

    1997-01-01

    Sound propagation has been studied in a magnetically trapped dilute Bose-Einstein condensate. Localized excitations were induced by suddenly modifying the trapping potential using the optical dipole force of a focused laser beam. The resulting propagation of sound was observed using a novel technique, rapid sequencing of nondestructive phase-contrast images. The speed of sound was determined as a function of density and found to be consistent with Bogoliubov theory. This method may generally be used to observe high-lying modes and perhaps second sound. copyright 1997 The American Physical Society

  11. Detection Classification and Localisation of Marine Mammals Using the Passive Acoustic Capabilities of an LFAS System

    NARCIS (Netherlands)

    Robert, M.K.; IJsselmuide, S.P. van; Beerens, S.P.

    2004-01-01

    World-wide a concern is emerging about the influence of man-made sound on marine life and more particularly marine mammals, who fully depend on sound in their natural behaviour. High power active sonars systems like Low Frequency Active Sonar (LFAS) are at stake. These systems, designed for long

  12. Real-Time Classification of Seagrass Meadows on Flat Bottom with Bathymetric Data Measured by a Narrow Multibeam Sonar System

    Directory of Open Access Journals (Sweden)

    Masahiro Hamana

    2016-01-01

    Full Text Available Seagrass meadows, one of the most important habitats for many marine species, provide essential ecological services. Thus, society must conserve seagrass beds as part of their sustainable development efforts. Conserving these ecosystems requires information on seagrass distribution and relative abundance, and an efficient, accurate monitoring system. Although narrow multibeam sonar systems (NMBSs are highly effective in resolving seagrass beds, post-processing methods are required to extract key data. The purpose of this study was to develop a simple method capable of detecting seagrass meadows and estimating their relative abundance in real time using an NMBS. Because most seagrass meadows grow on sandy seafloors, we proposed a way of discriminating seagrass meadows from the sand bed. We classify meadows into three categories of relative seagrass abundance using the 95% confidence level of beam depths and the depth range of the beam depth. These are respectively two times the standard deviation of beam depths, and the difference between the shallowest and the deepest depths in a 0.5 × 0.5 m grid cell sampled with several narrow beams. We examined Zostera caulescens Miki, but this simple NMBS method of seagrass classification can potentially be used to map seagrass meadows with longer shoots of other species, such as Posidonia, as both have gas filled cavities.

  13. Robot path Planning Using  SIFT and Sonar Sensor Fusion

    DEFF Research Database (Denmark)

    Plascencia, Alfredo; Raposo, Hector

    2007-01-01

    and evidential grid maps, respectively. The approach is illustrated using actual measurements from a laboratory robot. The sensory information is obtained from a sonar array and the Scale Invariant Feature Transform (SIFT) algorithm. Finally, the resulting two evidential maps based on Bayes and Dempster theories...

  14. Sonar: a multibase and parametric interface software for SDI

    International Nuclear Information System (INIS)

    Fonseca Passos, M.C.J. da

    1986-01-01

    Sonar - an automated service for selective dissemination of information (SDI) - developed by the Centro de Informacoes Nucleares (CIN) of the Comissao Nacional de Energia Nuclear (CNEN) is described. Emphasis is given to the multibase feature of the system based on the parametric interface between the system and an external data base reading subroutine. (Author) [pt

  15. Bayesian reconstruction of seafloor shape from side-scan sonar measurements using a Markov Random Field

    OpenAIRE

    Woock, P.; Pak, Alexey

    2014-01-01

    To explore the seafloor, a side-scan sonar emits a directed acoustic signal and then records the returning (reflected) signal intensity as a function of time. The inversion of that process is not unique: multiple shapes may lead to identical measured responses. In this work, we suggest a Bayesian approach to reconstructing the 3D shape of the seafloor from multiple sonar measurements, inspired by the state-of-the-art methods of inverse raytracing that originated in computer vision. The space ...

  16. Prospects for using sonar for underwater archeology on the Yenisei: surveying a 19th century shipwreck

    Science.gov (United States)

    Goncharov, A. E.; Mednikov, D. M.; Karelin, N. M.; Nasyrov, I. R.

    2016-11-01

    Current progress in underwater archeology is based on a rich arsenal of high-tech appliances, among which sonar technology plays a key role; it enables scientists not only to detect submerged archeological objects, but to examine them in high definition without having to conduct diving operations or use expensive underwater unmanned vehicles. While the majority of sensational scientific discoveries using sonar have been made in saltwater environments, freshwater ones, rivers in particular, have seen limited activity. The river Yenisei in central Siberia contains an unrecorded number of shipwrecks that await being discovered and studied. In this article we focus on the peculiarities of using sonar for detecting archeological sites on the Yenisei. This article is based on the results of the 2016 expedition, which has determined the location of Thames, a 19th century British steam schooner which was wrecked on the Yenisei.

  17. Recreational-Grade Sidescan Sonar: Transforming a Low-Cost Leisure Gadget into a High Resolution Riverbed Remote Sensing Tool

    Science.gov (United States)

    Hamill, D. D.; Buscombe, D.; Wheaton, J. M.; Wilcock, P. R.

    2016-12-01

    The size and spatial organization of bed material, bed texture, is a fundamental physical attribute of lotic ecosystems. Traditional methods to map bed texture (such as physical samples and underwater video) are limited by low spatial coverage, and poor precision in positioning. Recreational grade sidescan sonar systems now offer the possibility of imaging submerged riverbed sediments at coverages and resolutions sufficient to identify subtle changes in bed texture, in any navigable body of water, with minimal cost, expertise in sonar, or logistical effort, thereby facilitating the democratization of acoustic imaging of benthic environments, to support ecohydrological studies in shallow water, not subject to the rigors of hydrographic standards, nor the preserve of hydroacoustic expertise and proprietary hydrographic industry software. We investigate the possibility of using recreational grade sidescan sonar for sedimentary change detection using a case study of repeat sidescan imaging of mixed sand-gravel-rock riverbeds in a debris-fan dominated canyon river, at a coverage and resolution that meets the objectives of studies of the effects of changing bed substrates on salmonid spawning. A repeat substrate mapping analysis on data collected between 2012 and 2015 on the Colorado River in Glen, Marble, and Grand Canyons will be presented. A detailed method has been developed to interpret and analyze non-survey-grade sidescan sonar data, encoded within an open source software tool developed by the authors. An automated technique to quantify bed texture directly from sidescan sonar imagery is tested against bed sediment observations from underwater video and multibeam sonar. Predictive relationships between known bed sediment observations and bed texture metrics could provide an objective means to quantify bed textures and to relate changes in bed texture to biological components of an aquatic ecosystem, at high temporal frequency, and with minimal logistical effort

  18. Monitoring the US ATLAS Network Infrastructure with perfSONAR-PS

    CERN Document Server

    McKee, S; The ATLAS collaboration; Laurens, P; Severini, H; Wlodek, T; Wolff, S; Zurawski, J

    2012-01-01

    We will present our motivations for deploying and using the perfSONAR-PS Performance Toolkit at ATLAS sites in the United States and describe our experience in using it. This software creates a dedicated monitoring server, capable of collecting and performing a wide range of passive and active network measurements. Each independent instance is managed locally, but able to federate on a global scale; enabling a full view of the network infrastructure that spans domain boundaries. This information, available through web service interfaces, can easily be retrieved to create customized applications. USATLAS has developed a centralized “dashboard” offering network administrators, users, and decision makers the ability to see the performance of the network at a glance. The dashboard framework includes the ability to notify users (alarm) when problems are found, thus allowing rapid response to potential problems and making perfSONAR-PS crucial to the operation of our distributed computing infrastructure.

  19. AFSC/RACE/GAP/Prescott: Norton Sound Shoreline

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We assembled approximately 230,000 National Ocean Service (NOS) bathymetric soundings from 39 lead-line and single-beam echosounder hydrographic surveys conducted...

  20. AFSC/RACE/GAP/Prescott: Norton Sound Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We assembled approximately 230,000 National Ocean Service (NOS) bathymetric soundings from 39 lead-line and single-beam echosounder hydrographic surveys conducted...

  1. AFSC/RACE/GAP/Prescott: Norton Sound Features

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We assembled approximately 230,000 National Ocean Service (NOS) bathymetric soundings from 39 lead-line and single-beam echosounder hydrographic surveys conducted...

  2. AFSC/RACE/GAP/Prescott: Norton Sound Sediments

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We assembled approximately 230,000 National Ocean Service (NOS) bathymetric soundings from 39 lead-line and single-beam echosounder hydrographic surveys conducted...

  3. 'Merge' - A Filter for the Fusion of Dual-Frequency Sidescan Sonar Data

    National Research Council Canada - National Science Library

    Neill, Roger

    1997-01-01

    A filtering and data fusion technique is described which uses the correlation between the two data streams of a dual-frequency sidescan sonar in order to discriminate against noise and preferentially...

  4. Automatic Detection of Sand Ripple Features in Sidescan Sonar Imagery

    Science.gov (United States)

    2014-07-09

    Among the features used in forensic scientific fingerprint analysis are terminations or bifurcations of print ridges. Sidescan sonar imagery of ripple...always be pathological cases. The size of the blocks of pixels used in determining the ripple wavelength is evident in the output images on the right in

  5. Measurement of Rayleigh Wave Beams Using Angle Beam Wedge Transducers as the Transmitter and Receiver with Consideration of Beam Spreading.

    Science.gov (United States)

    Zhang, Shuzeng; Li, Xiongbing; Jeong, Hyunjo

    2017-06-20

    A theoretical model, along with experimental verification, is developed to describe the generation, propagation and reception of a Rayleigh wave using angle beam wedge transducers. The Rayleigh wave generation process using an angle beam wedge transducer is analyzed, and the actual Rayleigh wave sound source distributions are evaluated numerically. Based on the reciprocity theorem and considering the actual sound source, the Rayleigh wave beams are modeled using an area integral method. The leaky Rayleigh wave theory is introduced to investigate the reception of the Rayleigh wave using the angle beam wedge transducers, and the effects of the wave spreading in the wedge and transducer size are considered in the reception process. The effects of attenuations of the Rayleigh wave and leaky Rayleigh wave are discussed, and the received wave results with different sizes of receivers are compared. The experiments are conducted using two angle beam wedge transducers to measure the Rayleigh wave, and the measurement results are compared with the predictions using different theoretical models. It is shown that the proposed model which considers the wave spreading in both the sample and wedges can be used to interpret the measurements reasonably.

  6. New sonar waveforms for active torpedo warning using an LFAS system

    NARCIS (Netherlands)

    IJsselmuide, S.P. van; Beerens, S.P.; Doisy, Y.; Deruaz, L.

    2003-01-01

    Low Frequency Active Sonar (LFAS) systems are originally designed for ASW purposes. Although their main purpose is detection of submarines, they can, if adjusted waveforms are transmitted, also be used for detection of small fast moving targets (torpedoes). In this study the Detection,

  7. [A focused sound field measurement system by LabVIEW].

    Science.gov (United States)

    Jiang, Zhan; Bai, Jingfeng; Yu, Ying

    2014-05-01

    In this paper, according to the requirement of the focused sound field measurement, a focused sound field measurement system was established based on the LabVIEW virtual instrument platform. The system can automatically search the focus position of the sound field, and adjust the scanning path according to the size of the focal region. Three-dimensional sound field scanning time reduced from 888 hours in uniform step to 9.25 hours in variable step. The efficiency of the focused sound field measurement was improved. There is a certain deviation between measurement results and theoretical calculation results. Focal plane--6 dB width difference rate was 3.691%, the beam axis--6 dB length differences rate was 12.937%.

  8. Physics of thermo-acoustic sound generation

    Science.gov (United States)

    Daschewski, M.; Boehm, R.; Prager, J.; Kreutzbruck, M.; Harrer, A.

    2013-09-01

    We present a generalized analytical model of thermo-acoustic sound generation based on the analysis of thermally induced energy density fluctuations and their propagation into the adjacent matter. The model provides exact analytical prediction of the sound pressure generated in fluids and solids; consequently, it can be applied to arbitrary thermal power sources such as thermophones, plasma firings, laser beams, and chemical reactions. Unlike existing approaches, our description also includes acoustic near-field effects and sound-field attenuation. Analytical results are compared with measurements of sound pressures generated by thermo-acoustic transducers in air for frequencies up to 1 MHz. The tested transducers consist of titanium and indium tin oxide coatings on quartz glass and polycarbonate substrates. The model reveals that thermo-acoustic efficiency increases linearly with the supplied thermal power and quadratically with thermal excitation frequency. Comparison of the efficiency of our thermo-acoustic transducers with those of piezoelectric-based airborne ultrasound transducers using impulse excitation showed comparable sound pressure values. The present results show that thermo-acoustic transducers can be applied as broadband, non-resonant, high-performance ultrasound sources.

  9. Mapping of sound scattering objects in the northern part of the Barents Sea and their geological interpretation

    Science.gov (United States)

    Sokolov, S. Yu.; Moroz, E. A.; Abramova, A. S.; Zarayskaya, Yu. A.; Dobrolubova, K. O.

    2017-07-01

    On cruises 25 (2007) and 28 (2011) of the R/V Akademik Nikolai Strakhov in the northern part of the Barents Sea, the Geological Institute, Russian Academy of Sciences, conducted comprehensive research on the bottom relief and upper part of the sedimentary cover profile under the auspices of the International Polar Year program. One of the instrument components was the SeaBat 8111 shallow-water multibeam echo sounder, which can map the acoustic field similarly to a side scan sonar, which records the response both from the bottom and from the water column. In the operations area, intense sound scattering objects produced by the discharge of deep fluid flows are detected in the water column. The sound scattering objects and pockmarks in the bottom relief are related to anomalies in hydrocarbon gas concentrations in bottom sediments. The sound scattering objects are localized over Triassic sequences outcropping from the bottom. The most intense degassing processes manifest themselves near the contact of the Triassic sequences and Jurassic clay deposits, as well as over deep depressions in a field of Bouguer anomalies related to the basement of the Jurassic-Cretaceous rift system

  10. Multibeam sonar (DIDSON) assessment of American shad (Alosa sapidissima) approaching a hydroelectric dam

    Science.gov (United States)

    Grote, Ann B.; Bailey, Michael M.; Zydlewski, Joseph D.; Hightower, Joseph E.

    2014-01-01

    We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major dam removal and river restoration project. Multibeam sonar (dual-frequency identification sonar, DIDSON) surveys were conducted continuously at the fishway entrance from May to July in 2011. A 5% subsample of DIDSON data contained 43 793 fish targets, the majority of which were of Excellent (15.7%) or Good (73.01%) observation quality. Excellent quality DIDSON targets (n = 6876) were apportioned by species using a Bayesian mixture model based on four known fork length distributions (river herring (alewife,Alosa psuedoharengus, and blueback herring, Alosa aestivalis), American shad, Alosa sapidissima) and two size classes (one sea-winter and multi-sea-winter) of Atlantic salmon (Salmo salar). 76.2% of targets were assigned to the American shad distribution; Atlantic salmon accounted for 15.64%, and river herring 8.16% of observed targets. Shad-sized (99.0%) and salmon-sized (99.3%) targets approached the fishway almost exclusively during the day, whereas river herring-sized targets were observed both during the day (51.1%) and at night (48.9%). This approach demonstrates how multibeam sonar imaging can be used to evaluate community composition and species-specific movement patterns in systems where there is little overlap in the length distributions of target species.

  11. Studies of the system-environment interaction by electron-beam emission from a sounding rocket payload in the ionosphere

    International Nuclear Information System (INIS)

    Myers, N.B.

    1989-01-01

    The CHARGE-2 sounding rocket payload was designed to measure the transient and steady-state electrical charging of a space vehicle a low-Earth-orbit altitudes during the emission of a low-power electron beam from the vehicle. In addition to the electron gun, the payload contained several diagnostics to monitor plasma and waves resulting from the beam/space/vehicle interaction. The payload was separated into two sections, the larger section carried a 1-keV electron gun and was referred to as the mother vehicle. The smaller section, referred to as the daughter, was connected to the mother by an insulated, conducting tether and was deployed to a distance of up to 426 m across the geomagnetic field. Payload stabilization was obtained using thrusters that released cold nitrogen gas. In addition to performing electron beam experiments, the mother vehicle contained a high-voltage power supply capable of applying up to +450 V and 28 mA to the daughter through the tether. The 1-keV electron beam was generated at beam currents of 1 mA to 48 mA, measured at the exit aperture of the electron gun. Steady-state potentials of up to 560 V were measured for the mother vehicle. The daughter attained potentials of up to 1,000 V relative to the background ionosphere and collected currents up to 6.5 mA. Thruster firings increased the current collection to the vehicle firing the thrusters and resulted in neutralization of the payload. The CHARGE-2 experiment was unique in that for the first time a comparison was made of the current collection between an electron beam-emitting vehicle and a non-emitting vehicle at high potential (400 V to 1,000 V). The daughter current collection agreed well with the Parker-Murphy model, while the mother current collection always exceeded the Parker-Murphy limit and even exceeded the Langmuir-Blodgett predicted current below 240 km

  12. 3D sound in the telepresence project BEAMING

    DEFF Research Database (Denmark)

    Olesen, Søren Krarup; Markovic, Milos; Madsen, Esben

    2012-01-01

    three applications: A general purpose theatrical scene, a teaching situation and a medical patient-visiting-doctor scenario. The March 2012 project review deals with the teaching situation. This involves a single microphone recording followed by signal processing that reconstructs the spatial content......The involvement of Aalborg University in the EU project BEAMING will be presented. BEAMING deals with telepresence including multiple modalities; vision, haptics and audio, of which the latter is of main interest here. The setup consists of two types of locations: The Destination, where the Locals...... for the Visitor, 3D audio is provided through headphones. It is rendered based on the Locals' coordinates via a common Internet database including local positional tracking to ensure that information on the Visitor's head rotation has a minimum delay through the network. The BEAMING project currently addresses...

  13. Glomar challenger

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, J P

    1969-01-01

    The Glomar Challenger has a length of 400 ft, a 65-ft beam, and a depth of 27 ft 6-in. She has a draft of 20 ft with a gross displacement of 10,500 long tons. The principal specifications of the vessel are tabulated. To achieve dynamic positioning, 4 fixed thrusters and the vessel's 2 propulsion screws are utilized. The ''fix'' is obtained by placing a sonar beacon, with self contained batteries, on the ocean floor at a selected site. The vessel is provided with 4 hydrophones installed in the hull at the 4 corners of a square. The sonar beacon radiates sound waves at a fixed pulse rate. If the vessel is directly over the beacon, the sound waves will arrive at all hydrophones simultaneously. A difference in time of arrival indicates the vessel is off location. The sound signals received by the hydrophones are fed into a computer. They are changed into coordinate information, which serves as the primary function of determining corrective action by the vessel's propulsion and thruster system. The computer feeds back information into a control system, which enables the propulsion and thrusters to automatically respond, in order to keep the vessel on the predetermined location. The major drilling components are listed. The deep-sea drilling project is described. A summary of the first leg is given in tabular form.

  14. Modulation of the sound press level by the treatment of polymer diaphragms through ion implantation method

    International Nuclear Information System (INIS)

    Yeo, Sunmog; Park, Jaewon; Lee, Hojae

    2010-01-01

    We present two different surface modification treatments, an ion implantation, and an ion beam mixing, and show that the surface modifications caused by these treatments are useful tools to modulate the sound press level. The ion implantations on various polymer diaphragms cause an increase in the resonant frequency so that the sound press level is lowered at low frequencies. On the contrary, a Cu or Fe 2 O 3 coating by using an ion beam mixing method causes a decrease in the resonant frequency, resulting in a high sound press level at low frequencies. We discuss the physical reasons for the change in the sound press level due to the ion-implantation methods.

  15. Deep sea mega-geomorphology: Progress and problems

    Science.gov (United States)

    Bryan, W. B.

    1985-01-01

    Historically, marine geologists have always worked with mega-scale morphology. This is a consequence both of the scale of the ocean basins and of the low resolution of the observational remote sensing tools available until very recently. In fact, studies of deep sea morphology have suffered from a serious gap in observational scale. Traditional wide-beam echo sounding gave images on a scale of miles, while deep sea photography has been limited to scales of a few tens of meters. Recent development of modern narrow-beam echo sounding coupled with computer-controlled swath mapping systems, and development of high-resolution deep-towed side-scan sonar, are rapidly filling in the scale gap. These technologies also can resolve morphologic detail on a scale of a few meters or less. As has also been true in planetary imaging projects, the ability to observe phenomena over a range of scales has proved very effective in both defining processes and in placing them in proper context.

  16. Hearing abilities and sound reception of broadband sounds in an adult Risso's dolphin (Grampus griseus).

    Science.gov (United States)

    Mooney, T Aran; Yang, Wei-Cheng; Yu, Hsin-Yi; Ketten, Darlene R; Jen, I-Fan

    2015-08-01

    While odontocetes do not have an external pinna that guides sound to the middle ear, they are considered to receive sound through specialized regions of the head and lower jaw. Yet odontocetes differ in the shape of the lower jaw suggesting that hearing pathways may vary between species, potentially influencing hearing directionality and noise impacts. This work measured the audiogram and received sensitivity of a Risso's dolphin (Grampus griseus) in an effort to comparatively examine how this species receives sound. Jaw hearing thresholds were lowest (most sensitive) at two locations along the anterior, midline region of the lower jaw (the lower jaw tip and anterior part of the throat). Responses were similarly low along a more posterior region of the lower mandible, considered the area of best hearing in bottlenose dolphins. Left- and right-side differences were also noted suggesting possible left-right asymmetries in sound reception or differences in ear sensitivities. The results indicate best hearing pathways may vary between the Risso's dolphin and other odontocetes measured. This animal received sound well, supporting a proposed throat pathway. For Risso's dolphins in particular, good ventral hearing would support their acoustic ecology by facilitating echo-detection from their proposed downward oriented echolocation beam.

  17. U.S. and Australian Mine Warfare Sonar Performance Assessment Using SWAT and Hodgson Models

    National Research Council Canada - National Science Library

    Dubsky, Barbra

    2000-01-01

    The purpose of this thesis was to investigate a shallow coastal region to compile a detailed environmental picture of its sediment composition and water characteristics and from this model MCM sonar...

  18. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... The principles are similar to sonar used by boats and submarines. The ultrasound image is immediately visible ... principles involved in the sonar used by bats, ships and fishermen. When a sound wave strikes an ...

  19. Foreign Body Retrieval

    Medline Plus

    Full Text Available ... The principles are similar to sonar used by boats and submarines. The ultrasound image is immediately visible ... principles involved in the sonar used by bats, ships and fishermen. When a sound wave strikes an ...

  20. Neural network modeling of a dolphin's sonar discrimination capabilities

    OpenAIRE

    Andersen, Lars Nonboe; René Rasmussen, A; Au, WWL; Nachtigall, PE; Roitblat, H.

    1994-01-01

    The capability of an echo-locating dolphin to discriminate differences in the wall thickness of cylinders was previously modeled by a counterpropagation neural network using only spectral information of the echoes [W. W. L. Au, J. Acoust. Soc. Am. 95, 2728–2735 (1994)]. In this study, both time and frequency information were used to model the dolphin discrimination capabilities. Echoes from the same cylinders were digitized using a broadband simulated dolphin sonar signal with the transducer ...

  1. Nonlinear propagation of phase-conjugate focused sound beams in water

    Science.gov (United States)

    Brysev, A. P.; Krutyansky, L. M.; Preobrazhensky, V. L.; Pyl'nov, Yu. V.; Cunningham, K. B.; Hamilton, M. F.

    2000-07-01

    Nonlinear propagation of phase-conjugate, focused, ultrasound beams is studied. Measurements are presented of harmonic amplitudes along the axis and in the focal plane of the conjugate beam, and of the waveform and spectrum at the focus. A maximum peak pressure of 3.9 MPa was recorded in the conjugate beam. The measurements are compared with simulations based on the KZK equation, and satisfactory agreement is obtained.

  2. Sea-floor geology in northwestern Block Island Sound, Rhode Island

    Science.gov (United States)

    McMullen, Katherine Y.; Poppe, Lawrence J.; Ackerman, Seth D.; Blackwood, Dann S.; Woods, D.A.

    2014-01-01

    Multibeam-echosounder and sidescan-sonar data, collected by the National Oceanic and Atmospheric Administration in a 69-square-kilometer area of northwestern Block Island Sound, are used with sediment samples, and still and video photography of the sea floor, collected by the U.S. Geological Survey at 43 stations within this area, to interpret the sea-floor features and sedimentary environments. Features on the sea floor include boulders, sand waves, scour depressions, modern marine sediments, and trawl marks. Boulders, which are often several meters wide, are found in patches in the shallower depths and tend to be overgrown with sessile flora and fauna. They are lag deposits of winnowed glacial drift, and reflect high-energy environments characterized by processes associated with erosion and nondeposition. Sand waves and megaripples tend to have crests that either trend parallel to shore with 20- to 50-meter (m) wavelengths or trend perpendicular to shore with several-hundred-meter wavelengths. The sand waves reflect sediment transport directions perpendicular to shore by waves, and parallel to shore by tidal or wind-driven currents, respectively. Scour depressions, which are about 0.5 m lower than the surrounding sea floor, have floors of gravel and coarser sand than bounding modern marine sediments. These scour depressions, which are conspicuous in the sidescan-sonar data because of their more highly reflective coarser sediment floors, are likely formed by storm-generated, seaward-flowing currents and maintained by the turbulence in bottom currents caused by their coarse sediments. Areas of the sea floor with modern marine sediments tend to be relatively flat to current-rippled and sandy.

  3. Generation of the vorticity mode by sound in a Bingham plastic

    Science.gov (United States)

    Perelomova, Anna; Wojda, Pawel

    2011-10-01

    This study investigates interaction between acoustic and non-acoustic modes, such as vorticity mode, in some class of a non-newtonian fluid called Bingham plastic. The instantaneous equations describing interaction between different modes are derived. The attention is paid to the nonlinear effects in the field of intense sound. The resulting equations which describe dynamics of both sound and the vorticity mode apply to both periodic and aperiodic sound of any waveform. They use only instantaneous quantities and do not imply averaging over the sound period. The theory is illustrated by an example of acoustic force of vorticity induced in the field of a Gaussian sound beam. Some unusual peculiarities in both sound and the vorticity induced in its field as compared to a newtonian fluid, are discovered.

  4. A Spatial Reference Grid for Real-Time Autonomous Underwater Modeling using 3-D Sonar

    Energy Technology Data Exchange (ETDEWEB)

    Auran, P.G.

    1996-12-31

    The offshore industry has recognized the need for intelligent underwater robotic vehicles. This doctoral thesis deals with autonomous underwater vehicles (AUVs) and concentrates on a data representation for real-time image formation and analysis. Its main objective is to develop a 3-D image representation suitable for autonomous perception objectives underwater, assuming active sonar as the main sensor for perception. The main contributions are: (1) A dynamical image representation for 3-D range data, (2) A basic electronic circuit and software system for 3-D sonar sampling and amplitude thresholding, (3) A model for target reliability, (4) An efficient connected components algorithm for 3-D segmentation, (5) A method for extracting general 3-D geometrical representations from segmented echo clusters, (6) Experimental results of planar and curved target modeling. 142 refs., 120 figs., 10 tabs.

  5. The Blackboard Model of Computer Programming Applied to the Interpretation of Passive Sonar Data

    National Research Council Canada - National Science Library

    Liebing, David

    1997-01-01

    ... (location, course, speed, classification, etc.). At present the potential volume of data produced by modern sonar systems is so large that unless some form of computer assistance is provided with the interpretation of this data, information...

  6. Sound and sound sources

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Wahlberg, Magnus

    2017-01-01

    There is no difference in principle between the infrasonic and ultrasonic sounds, which are inaudible to humans (or other animals) and the sounds that we can hear. In all cases, sound is a wave of pressure and particle oscillations propagating through an elastic medium, such as air. This chapter...... is about the physical laws that govern how animals produce sound signals and how physical principles determine the signals’ frequency content and sound level, the nature of the sound field (sound pressure versus particle vibrations) as well as directional properties of the emitted signal. Many...... of these properties are dictated by simple physical relationships between the size of the sound emitter and the wavelength of emitted sound. The wavelengths of the signals need to be sufficiently short in relation to the size of the emitter to allow for the efficient production of propagating sound pressure waves...

  7. Recommendations for improved and coherent acquisition and processing of backscatter data from seafloor-mapping sonars

    Science.gov (United States)

    Lamarche, Geoffroy; Lurton, Xavier

    2018-06-01

    Multibeam echosounders are becoming widespread for the purposes of seafloor bathymetry mapping, but the acquisition and the use of seafloor backscatter measurements, acquired simultaneously with the bathymetric data, are still insufficiently understood, controlled and standardized. This presents an obstacle to well-accepted, standardized analysis and application by end users. The Marine Geological and Biological Habitat Mapping group (Geohab.org) has long recognized the need for better coherence and common agreement on acquisition, processing and interpretation of seafloor backscatter data, and established the Backscatter Working Group (BSWG) in May 2013. This paper presents an overview of this initiative, the mandate, structure and program of the working group, and a synopsis of the BSWG Guidelines and Recommendations to date. The paper includes (1) an overview of the current status in sensors and techniques available in seafloor backscatter data from multibeam sonars; (2) the presentation of the BSWG structure and results; (3) recommendations to operators, end-users, sonar manufacturers, and software developers using sonar backscatter for seafloor-mapping applications, for best practice methods and approaches for data acquisition and processing; and (4) a discussion on the development needs for future systems and data processing. We propose for the first time a nomenclature of backscatter processing levels that affords a means to accurately and efficiently describe the data processing status, and to facilitate comparisons of final products from various origins.

  8. A simulation of temperature influence on echolocation click beams of the Indo-Pacific humpback dolphin (Sousa chinensis).

    Science.gov (United States)

    Song, Zhongchang; Zhang, Yu; Wang, Xianyan; Wei, Chong

    2017-10-01

    A finite element method was used to investigate the temperature influence on sound beams of the Indo-Pacific humpback dolphin. The numerical models of a dolphin, which originated from previous computed tomography (CT) scanning and physical measurement results, were used to investigate sound beam patterns of the dolphin in temperatures from 21 °C to 39 °C, in increments of 2 °C. The -3 dB beam widths across the temperatures ranged from 9.3° to 12.6°, and main beam angle ranged from 4.7° to 7.2° for these temperatures. The subsequent simulation suggested that the dolphin's sound beam patterns, side lobes in particular, were influenced by temperature.

  9. Acoustic beam control in biomimetic projector via velocity gradient

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Xiaowei; Dong, Erqian; Song, Zhongchang [Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education, Xiamen University, Xiamen 361005 (China); Zhang, Yu, E-mail: yuzhang@xmu.edu.cn, E-mail: dzk@psu.edu; Tang, Liguo [Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education, Xiamen University, Xiamen 361005 (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005 (China); Cao, Wenwu, E-mail: yuzhang@xmu.edu.cn, E-mail: dzk@psu.edu [Department of Mathematics and Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Li, Songhai [Sanya Key Laboratory of Marin Mammal and Marine Bioacoustics, Sanya Institute of Deep-Sea Science and Engineering, Chinese Academy of Science, Sanya 57200 (China); Zhang, Sai [Faculty of Science, Jiangsu University, Zhenjiang 212013 (China)

    2016-07-04

    A biomimetic projector (BioP) based on computerized tomography of pygmy sperm whale's biosonar system has been designed using gradient-index (GRIN) material. The directivity of this BioP device was investigated as function of frequency and the velocity gradient of the GRIN material. A strong beam control over a broad bandwidth at the subwavelength scale has been achieved. Compared with a bare subwavelength source, the main lobe pressure of the BioP is about five times as high and the angular resolution is one order of magnitude better. Our results indicate that this BioP has excellent application potential in miniaturized underwater sonars.

  10. The Delphinus array for passive marine mammal detection

    NARCIS (Netherlands)

    Sheldon-Robert, M.K.; Beerens, S.P.; Lam, F.P.A.

    2008-01-01

    To protect marine mammals from potential negative impacts of high-power sound from tactical sonar, the use of passive acoustic monitoring prior and during sonar exercises is a possible non-intrusive solution for the monitoring requirements for naval forces. Particularly deep-diving beaked whales

  11. Automatic Sound Generation for Spherical Objects Hitting Straight Beams Based on Physical Models.

    Science.gov (United States)

    Rauterberg, M.; And Others

    Sounds are the result of one or several interactions between one or several objects at a certain place and in a certain environment; the attributes of every interaction influence the generated sound. The following factors influence users in human/computer interaction: the organization of the learning environment, the content of the learning tasks,…

  12. Oculina Banks Bathymetry 2002 from Multi-beam and Sidescan Sonar Surveys (NODC Accession 0090252)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are the result of a multi-beam echosounder survey conducted in the OHAPC by the M/V Liberty Star in October 2002. Two forms of data are available: 1)...

  13. Data fusion from multiple passive sonar nodes for target localisation and false alarm reduction

    NARCIS (Netherlands)

    Hunter, A.J.; Fillinger, L.; Zampolli, M.; Clarijs, M.C.

    2012-01-01

    A PHD particle filter implementation has been detailed for the fusion of measurements from multiple passive sonar nodes. It has been demonstrated on simulated metadata and on experimental passive acoustic data of divers and small boats collected in an operational port environment. Fusion at the

  14. Advanced signal processing theory and implementation for sonar, radar, and non-invasive medical diagnostic systems

    CERN Document Server

    Stergiopoulos, Stergios

    2009-01-01

    Integrates topics of signal processing from sonar, radar, and medical system technologies by identifying their concept similarities. This book covers non-invasive medical diagnostic system applications, including intracranial ultrasound, a technology that attempts to address non-invasive detection on brain injuries and stroke.

  15. SIMONA: A multi-purpose acoustic data simulator for development and testing of sonar signal processing

    NARCIS (Netherlands)

    Robert, M.K.; Groen, J.; Konijnendijk, N.J.

    2005-01-01

    The development of undersea defence technologies such as sonar relies heavily on the availability of high quality acoustic data. However, data acquisition is particularly expensive as sea trials involve experienced manpower and costly high-tech equipment. Also, at sea, the environment remains

  16. The influence of air-filled structures on wave propagation and beam formation of a pygmy sperm whale (Kogia breviceps) in horizontal and vertical planes.

    Science.gov (United States)

    Song, Zhongchang; Zhang, Yu; Thornton, Steven W; Li, Songhai; Dong, Jianchen

    2017-10-01

    The wave propagation, sound field, and transmission beam pattern of a pygmy sperm whale (Kogia breviceps) were investigated in both the horizontal and vertical planes. Results suggested that the signals obtained at both planes were similarly characterized with a high peak frequency and a relatively narrow bandwidth, close to the ones recorded from live animals. The sound beam measured outside the head in the vertical plane was narrower than that of the horizontal one. Cases with different combinations of air-filled structures in both planes were used to study the respective roles in controlling wave propagation and beam formation. The wave propagations and beam patterns in the horizontal and vertical planes elucidated the important reflection effect of the spermaceti and vocal chambers on sound waves, which was highly significant in forming intensive forward sound beams. The air-filled structures, the forehead soft tissues and skull structures formed wave guides in these two planes for emitted sounds to propagate forward.

  17. Beaming teaching application: recording techniques for spatial xylophone sound rendering

    DEFF Research Database (Denmark)

    Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup

    2012-01-01

    BEAMING is a telepresence research project aiming at providing a multimodal interaction between two or more participants located at distant locations. One of the BEAMING applications allows a distant teacher to give a xylophone playing lecture to the students. Therefore, rendering of the xylophon...... to spatial improvements mainly in terms of the Apparent Source Width (ASW). Rendered examples are subjectively evaluated in listening tests by comparing them with binaural recording....

  18. Propagation and Signal Modeling

    Science.gov (United States)

    Jensen, Finn B.

    The use of sound in the sea is ubiquitous: Apart from the military aspect of trying to detect an adversary’s mines and submarines, ship-mounted sonars measure water depth, ship speed, and the presence of fish shoals. Side-scan systems are used for mapping the bottom topography, sub-bottom profilers for getting information about the deeper layering, and other sonar systems for locating pipelines and cables on the seafloor. Sound is also used for navigating submerged vehicles, for underwater communications and for tracking marine mammals. Finally, in the realm of ‘acoustical oceanography’ and ‘ocean acoustic tomography,’ sound is used for measuring physical parameters of the ocean environment and for monitoring oceanic processes [1-6].

  19. Foley Sounds vs Real Sounds

    DEFF Research Database (Denmark)

    Trento, Stefano; Götzen, Amalia De

    2011-01-01

    This paper is an initial attempt to study the world of sound effects for motion pictures, also known as Foley sounds. Throughout several audio and audio-video tests we have compared both Foley and real sounds originated by an identical action. The main purpose was to evaluate if sound effects...

  20. 78 FR 13869 - Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy...

    Science.gov (United States)

    2013-03-01

    ...-123-LNG; 12-128-NG; 12-148-NG; 12- 158-NG] Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; CE FLNG, LLC; Consolidated...-NG Puget Sound Energy, Inc Order granting long- term authority to import/export natural gas from/to...

  1. Killer whale presence in relation to naval sonar activity and prey abundance in northern Norway

    NARCIS (Netherlands)

    Kuningas, S.; Kvadsheim, P.H.; Lam, F.P.A.; Miller, P.J.O.

    2013-01-01

    In this study, retrospective data on naval sonar activity and prey abundance were correlated with killer whale sightings within a fjord basin in northern Norway. In addition, passive acoustic and visual marine mammal surveys were conducted before, during, and after a specific navy exercise in 2006.

  2. Final report of DOE project "Detection, Localization and Diagnosis of Performance Problems Using PerfSONAR"

    Energy Technology Data Exchange (ETDEWEB)

    Dovrolis, Konstantinos [Georgia Tech

    2014-04-15

    We present the development of a middleware service, called Pythia, that is able to detect, localize, and diagnose performance problems in the network paths that interconnect research sites that are of interest to DOE. The proposed service can analyze perfSONAR data collected from all participating sites.

  3. Sound radiation contrast in MR phase images. Method for the representation of elasticity, sound damping, and sound impedance changes; Schallstrahlungskontrast in MR-Phasenbildern. Methode zur Darstellung von Elastizitaets-, Schalldaempfungs- und Schallimpedanzaenderungen

    Energy Technology Data Exchange (ETDEWEB)

    Radicke, Marcus

    2009-12-18

    The method presented in this thesis combines ultrasound techniques with the magnetic-resonance tomography (MRT). An ultrasonic wave generates in absorbing media a static force in sound-propagation direction. The force leads at sound intensities of some W/cm{sup 2} and a sound frequency in the lower MHz range to a tissue shift in the micrometer range. This tissue shift depends on the sound power, the sound frequency, the sound absorption, and the elastic properties of the tissue. A MRT sequence of the Siemens Healthcare AG was modified so that it measures (indirectly) the tissue shift, codes as grey values, and presents as 2D picture. By means of the grey values the sound-beam slope in the tissue can be visualized, and so additionally sound obstacles (changes of the sound impedance) can be detected. By the MRT images token up spatial changes of the tissue parameters sound absorption and elasticity can be detected. In this thesis measurements are presented, which show the feasibility and future chances of this method especially for the mammary-cancer diagnostics. [German] Die in dieser Arbeit praesentierte Methode kombiniert Ultraschalltechniken mit der Magnetresonanztomographie (MRT). Eine Ultraschallwelle ruft in absorbierenden Medien eine statische Kraft in Schallausbreitungsrichtung hervor. Die Kraft fuehrt bei Schallintensitaeten von einigen W/cm{sup 2} und einer Schallfrequenz im niederen MHz-Bereich zu einer Gewebeverschiebung im Mikrometerbereich. Diese Gewebeverschiebung haengt ab von der Schallleistung, der Schallfrequenz, der Schallabsorption und den elastischen Eigenschaften des Gewebes. Es wurde eine MRT-Sequenz der Siemens Healthcare AG modifiziert, so dass sie (indirekt) die Gewebeverschiebung misst, als Grauwerte kodiert und als 2D-Bild darstellt. Anhand der Grauwerte kann der Schallstrahlverlauf in dem Gewebe visualisiert werden, und so koennen zusaetzlich Schallhindernisse (Aenderungen der Schallkennimpedanz) aufgespuert werden. Mit den

  4. Wall-corner classification using sonar: a new approach based on geometric features.

    Science.gov (United States)

    Martínez, Milagros; Benet, Ginés

    2010-01-01

    Ultrasonic signals coming from rotary sonar sensors in a robot gives us several features about the environment. This enables us to locate and classify the objects in the scenario of the robot. Each object and reflector produces a series of peaks in the amplitude of the signal. The radial and angular position of the sonar sensor gives information about location and their amplitudes offer information about the nature of the surface. Early works showed that the amplitude can be modeled and used to classify objects with very good results at short distances-80% average success in classifying both walls and corners at distances less than 1.5 m. In this paper, a new set of geometric features derived from the amplitude analysis of the echo is presented. These features constitute a set of characteristics that can be used to improve the results of classification at distances from 1.5 m to 4 m. Also, a comparative study on classification algorithms widely used in pattern recognition techniques has been carried out for sensor distances ranging between 0.5 to 4 m, and with incidence angles ranging between 20° to 70°. Experimental results show an enhancement on the success in classification rates when these geometric features are considered.

  5. Blue whales respond to anthropogenic noise.

    Directory of Open Access Journals (Sweden)

    Mariana L Melcón

    Full Text Available Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to stop calling at any time of day, showing no diel pattern in their sensitivity to sonar. Conversely, the likelihood of whales emitting calls increased when ship sounds were nearby. Whales did not show a differential response to ship noise as a function of the time of the day either. These results demonstrate that anthropogenic noise, even at frequencies well above the blue whales' sound production range, has a strong probability of eliciting changes in vocal behavior. The long-term implications of disruption in call production to blue whale foraging and other behaviors are currently not well understood.

  6. 3S2: Behavioral Response Studies of Cetaceans to Navy Sonar Signals in Norwegian Waters

    Science.gov (United States)

    2015-09-30

    Sonar Signals in Norwegian Waters Peter L. Tyack University of St Andrews School of Biology Scottish Oceans Institute East Sands St Andrews...with a tagged minke whale. Data in the top 4 panels were derived from observations from the trackboat (‘ MOB ’). Note the strong change in diving

  7. Development of Optophone with No Diaphragm and Application to Sound Measurement in Jet Flow

    Directory of Open Access Journals (Sweden)

    Yoshito Sonoda

    2012-01-01

    Full Text Available The optophone with no diaphragm, which can detect sound waves without disturbing flow of air and sound field, is presented as a novel sound measurement technique and the present status of development is reviewed in this paper. The method is principally based on the Fourier optics and the sound signal is obtained by detecting ultrasmall diffraction light generated from phase modulation by sounds. The principle and theory, which have been originally developed as a plasma diagnostic technique to measure electron density fluctuations in the nuclear fusion research, are briefly introduced. Based on the theoretical analysis, property and merits as a wave-optical sound detection are presented, and the fundamental experiments and results obtained so far are reviewed. It is shown that sounds from about 100 Hz to 100 kHz can be simultaneously detected by a visible laser beam, and the method is very useful to sound measurement in aeroacoustics. Finally, present main problems of the optophone for practical uses in sound and/or noise measurements and the image of technology expected in the future are shortly shown.

  8. 75 FR 81284 - Nationwide Use of High Frequency and Ultra High Frequency Active SONAR Technology; Draft...

    Science.gov (United States)

    2010-12-27

    ... Frequency and Ultra High Frequency Active SONAR Technology; Draft Programmatic Environmental Assessment and... Programmatic Environmental Assessment (PEA) for the Nationwide Use of High Frequency (HF) and Ultra High... potential impacts of each alternative on the human and natural environments. DATES: Comments and related...

  9. 78 FR 70567 - Nationwide Use of High Frequency and Ultra High Frequency Active SONAR Technology; Final...

    Science.gov (United States)

    2013-11-26

    ... Frequency and Ultra High Frequency Active SONAR Technology; Final Programmatic Environmental Assessment and... each alternative on the human and natural environments. FOR FURTHER INFORMATION CONTACT: If you have... Programmatic Environmental Assessment The scope of the PEA focuses on potential impacts associated with the...

  10. The application of standard definitions of sound to the fields of underwater acoustics and acoustical oceanography

    Science.gov (United States)

    Carey, William M.

    2004-05-01

    Recent societal concerns have focused attention on the use of sound as a probe to investigate the oceans and its use in naval sonar applications. The concern is the impact the use of sound may have on marine mammals and fishes. The focus has changed the fields of acoustical oceanography (AO) and underwater acoustics (UW) because of the requirement to communicate between disciplines. Multiple National Research Council publications, Dept. of Navy reports, and several monographs have been written on this subject, and each reveals the importance as well as the misapplication of ASA standards. The ANSI-ASA standards are comprehensive, however not widely applied. The clear definition of standards and recommendations of their use is needed for both scientists and government agencies. Traditionally the U.S. Navy has been responsible for UW standards and calibration; the ANSI-ASA standards have been essential. However, recent changes in the Navy and its laboratory structure may necessitate a more formal recognition of ANSI-ASA standards and perhaps incorporation of UW-AO in the Bureau of Standards. A separate standard for acoustical terminology, reference levels, and notation used in the UW-AO is required. Since the problem is global, a standard should be compatible and cross referenced with the International Standard (CEI/IEC 27-3).

  11. Oceanographic data collected during the EX1602 Mission System Shakedown/CAPSTONE Mapping on NOAA Ship OKEANOS EXPLORER in the North Pacific Ocean from 2016-02-12 to 2016-02-17 (NCEI Accession 0145342)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations used the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp sub-bottom profiler...

  12. 3D Imaging with a Sonar Sensor and an Automated 3-Axes Frame for Selective Spraying in Controlled Conditions

    Directory of Open Access Journals (Sweden)

    David Reiser

    2017-02-01

    Full Text Available Autonomous selective spraying could be a way for agriculture to reduce production costs, save resources, protect the environment and help to fulfill specific pesticide regulations. The objective of this paper was to investigate the use of a low-cost sonar sensor for autonomous selective spraying of single plants. For this, a belt driven autonomous robot was used with an attached 3-axes frame with three degrees of freedom. In the tool center point (TCP of the 3-axes frame, a sonar sensor and a spray valve were attached to create a point cloud representation of the surface, detect plants in the area and perform selective spraying. The autonomous robot was tested on replicates of artificial crop plants. The location of each plant was identified out of the acquired point cloud with the help of Euclidian clustering. The gained plant positions were spatially transformed from the coordinates of the sonar sensor to the valve location to determine the exact irrigation points. The results showed that the robot was able to automatically detect the position of each plant with an accuracy of 2.7 cm and could spray on these selected points. This selective spraying reduced the used liquid by 72%, when comparing it to a conventional spraying method in the same conditions.

  13. Sound Use, Sequential Behavior and Ecology of Foraging Bottlenose Dolphins, Tursiops Truncatus

    Science.gov (United States)

    1999-09-01

    Richards, 1992; Nowacek et al, 1995). In addition, we have extensive information about the distribution, anatomy , life history, diet, and general... anatomy of a sonar signal generator. In Animal Sonar: Processes and Performance (ed. P. E. Nachtigall and P. W. B. Moore), pp. 67-77. Plenum Press...Mwanza, N. (1994). Day-journey length and daily diet of solitary male gorillas in lowland and highland habitats. International journal of Primatology

  14. Unified model to predict flexural shear behavior of externally bonded RC beams

    International Nuclear Information System (INIS)

    Colotti, V.; Spadea, G.; Swamy, R.N.

    2006-01-01

    Structural strengthening with externally bonded reinforcement is now recognized as a cost-effective, structurally sound and practically efficient method of rehabilitating deteriorating and damaged reinforced concrete beams. There is now an urgent need to develop a sound engineering basis which can predict the failure loads of all such strengthened beams in a reliable and consistent manner. Existing models to predict the behavior at ultimate of strengthened beams suffer from many limitations and weaknesses. This paper presents a unified global model, based on the Strut-and-Tie approach, to predict the failure loads of reinforced concrete beams strengthened for flexure and/or shear. This structural model is based on rational engineering principles, considers all the possible failure modes, and incorporates the load transfer mechanism bond to reflect the debonding phenomena which has a dominant influence on the failure process of plated beams. The model is validated against about 200 strengthened beam test reported in the literature and failing in flexure and/or shear, involving a large number of structural variables and steel, carbon and glass fiber reinforced polymer laminates as reinforcing medium. (author)

  15. Okeanos Explorer (EX1703): Howland/Baker PRIMNM and PIPA (ROV/Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  16. Okeanos Explorer (EX1702): American Samoa Expedition: Suesuega o le Moana o Amerika Samoa (ROV/Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  17. Okeanos Explorer (EX1705): American Samoa, Kingman/Palmyra, Jarvis (ROV & Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  18. Okeanos Explorer (EX1706): Johnston Atoll (ROV/Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  19. High frequency ion sound waves associated with Langmuir waves in type III radio burst source regions

    Directory of Open Access Journals (Sweden)

    G. Thejappa

    2004-01-01

    Full Text Available Short wavelength ion sound waves (2-4kHz are detected in association with the Langmuir waves (~15-30kHz in the source regions of several local type III radio bursts. They are most probably not due to any resonant wave-wave interactions such as the electrostatic decay instability because their wavelengths are much shorter than those of Langmuir waves. The Langmuir waves occur as coherent field structures with peak intensities exceeding the Langmuir collapse thresholds. Their scale sizes are of the order of the wavelength of an ion sound wave. These Langmuir wave field characteristics indicate that the observed short wavelength ion sound waves are most probably generated during the thermalization of the burnt-out cavitons left behind by the Langmuir collapse. Moreover, the peak intensities of the observed short wavelength ion sound waves are comparable to the expected intensities of those ion sound waves radiated by the burnt-out cavitons. However, the speeds of the electron beams derived from the frequency drift of type III radio bursts are too slow to satisfy the needed adiabatic ion approximation. Therefore, some non-linear process such as the induced scattering on thermal ions most probably pumps the beam excited Langmuir waves towards the lower wavenumbers, where the adiabatic ion approximation is justified.

  20. Dose-response relationships for the onset of avoidance of sonar by free-ranging killer whales

    NARCIS (Netherlands)

    Miller, P.J.O.; Antunes, R.N.; Wensveen, P.J.; Samarra, F.I.P.; Alves, A.C.; Tyack, P.L.; Kvadsheim, P.H.; Kleivane, L.; Lam, F.P.A.; Ainslie, M.A.; Thomas, L.

    2014-01-01

    Eight experimentally controlled exposures to 1−2 kHz or 6−7 kHz sonar signals were conducted with four killer whale groups. The source level and proximity of the source were increased during each exposure in order to reveal response thresholds. Detailed inspection of movements during each exposure

  1. Sound

    CERN Document Server

    Robertson, William C

    2003-01-01

    Muddled about what makes music? Stuck on the study of harmonics? Dumbfounded by how sound gets around? Now you no longer have to struggle to teach concepts you really don t grasp yourself. Sound takes an intentionally light touch to help out all those adults science teachers, parents wanting to help with homework, home-schoolers seeking necessary scientific background to teach middle school physics with confidence. The book introduces sound waves and uses that model to explain sound-related occurrences. Starting with the basics of what causes sound and how it travels, you'll learn how musical instruments work, how sound waves add and subtract, how the human ear works, and even why you can sound like a Munchkin when you inhale helium. Sound is the fourth book in the award-winning Stop Faking It! Series, published by NSTA Press. Like the other popular volumes, it is written by irreverent educator Bill Robertson, who offers this Sound recommendation: One of the coolest activities is whacking a spinning metal rod...

  2. Monitoring the US ATLAS Network Infrastructure with perfSONAR-PS

    International Nuclear Information System (INIS)

    McKee, Shawn; Lake, Andrew; Laurens, Philippe; Severini, Horst; Wlodek, Tomasz; Wolff, Stephen; Zurawski, Jason

    2012-01-01

    Global scientific collaborations, such as ATLAS, continue to push the network requirements envelope. Data movement in this collaboration is routinely including the regular exchange of petabytes of datasets between the collection and analysis facilities in the coming years. These requirements place a high emphasis on networks functioning at peak efficiency and availability; the lack thereof could mean critical delays in the overall scientific progress of distributed data-intensive experiments like ATLAS. Network operations staff routinely must deal with problems deep in the infrastructure; this may be as benign as replacing a failing piece of equipment, or as complex as dealing with a multi-domain path that is experiencing data loss. In either case, it is crucial that effective monitoring and performance analysis tools are available to ease the burden of management. We will report on our experiences deploying and using the perfSONAR-PS Performance Toolkit at ATLAS sites in the United States. This software creates a dedicated monitoring server, capable of collecting and performing a wide range of passive and active network measurements. Each independent instance is managed locally, but able to federate on a global scale; enabling a full view of the network infrastructure that spans domain boundaries. This information, available through web service interfaces, can easily be retrieved to create customized applications. The US ATLAS collaboration has developed a centralized “dashboard” offering network administrators, users, and decision makers the ability to see the performance of the network at a glance. The dashboard framework includes the ability to notify users (alarm) when problems are found, thus allowing rapid response to potential problems and making perfSONAR-PS crucial to the operation of our distributed computing infrastructure.

  3. Measurement of fish movements at depths to 6000 m using a deep-ocean lander incorporating a short base-line sonar utilizing miniature code-activated transponder technology

    Science.gov (United States)

    Bagley, P. M.; Bradley, S.; Priede, I. G.; Gray, P.

    1999-12-01

    Most research on animal behaviour in the deep ocean (to depths of 6000 m) is restricted to the capture of dead specimens or viewing activity over small areas of the sea floor by means of cameras or submersibles. This paper describes the use of a miniature acoustic code-activated transponder (CAT) tag and short base-line sonar to track the movements of deep-sea fish in two dimensions over an area 1 km in diameter centred on a lander platform. The CAT tags and sonar are transported to the deep-sea floor by means of a subsea mooring which is ballasted so that it lands and remains on the sea floor for the duration of the tracking experiment (the lander). A description of the CAT, lander and short base-line sonar is given. Results are presented to illustrate the operation of the system.

  4. Method and Apparatus for Characterizing Pressure Sensors using Modulated Light Beam Pressure

    Science.gov (United States)

    Youngquist, Robert C. (Inventor)

    2003-01-01

    Embodiments of apparatuses and methods are provided that use light sources instead of sound sources for characterizing and calibrating sensors for measuring small pressures to mitigate many of the problems with using sound sources. In one embodiment an apparatus has a light source for directing a beam of light on a sensing surface of a pressure sensor for exerting a force on the sensing surface. The pressure sensor generates an electrical signal indicative of the force exerted on the sensing surface. A modulator modulates the beam of light. A signal processor is electrically coupled to the pressure sensor for receiving the electrical signal.

  5. Okeanos Explorer (EX1606): CAPSTONE Wake Island Unit PRIMNM (ROV & Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen 3260 chirp...

  6. Okeanos Explorer (EX1608): FY17 Ship and ROV Shakedown

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen 3260 chirp...

  7. Okeanos Explorer (EX1602): Mission System Shakedown/CAPSTONE Mapping

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp sub-bottom...

  8. Okeanos Explorer (EX1605L2): CAPSTONE CNMI and Mariana Trench MNM (Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen 3260 chirp...

  9. Do top predators cue on sound production by mesopelagic prey?

    Science.gov (United States)

    Baumann-Pickering, S.; Checkley, D. M., Jr.; Demer, D. A.

    2016-02-01

    Deep-scattering layer (DSL) organisms, comprising a variety of mesopelagic fishes, and squids, siphonophores, crustaceans, and other invertebrates, are preferred prey for numerous large marine predators, e.g. cetaceans, seabirds, and fishes. Some of the DSL species migrate from depth during daylight to feed near the surface at night, transitioning during dusk and dawn. We investigated if any DSL organisms create sound, particularly during the crepuscular periods. Over several nights in summer 2015, underwater sound was recorded in the San Diego Trough using a high-frequency acoustic recording package (HARP, 10 Hz to 100 kHz), suspended from a drifting surface float. Acoustic backscatter from the DSL was monitored nearby using a calibrated multiple-frequency (38, 70, 120, and 200 kHz) split-beam echosounder (Simrad EK60) on a small boat. DSL organisms produced sound, between 300 and 1000 Hz, and the received levels were highest when the animals migrated past the recorder during ascent and descent. The DSL are globally present, so the observed acoustic phenomenon, if also ubiquitous, has wide-reaching implications. Sound travels farther than light or chemicals and thus can be sensed at greater distances by predators, prey, and mates. If sound is a characteristic feature of pelagic ecosystems, it likely plays a role in predator-prey relationships and overall ecosystem dynamics. Our new finding inspires numerous questions such as: Which, how, and why have DSL organisms evolved to create sound, for what do they use it and under what circumstances? Is sound production by DSL organisms truly ubiquitous, or does it depend on the local environment and species composition? How may sound production and perception be adapted to a changing environment? Do predators react to changes in sound? Can sound be used to quantify the composition of mixed-species assemblages, component densities and abundances, and hence be used in stock assessment or predictive modeling?

  10. Olympic Coast National Marine Sanctuary - mos120_0602b - Side scan sonar mosaic from survey effort 120_0602

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (70-90 m water depths) was mosaiced from acoustic data collected in 2006 aboard the R/V Tatoosh. A Klein System 3000...

  11. Olympic Coast National Marine Sanctuary - mos120_0602a - Side scan sonar mosaic from survey effort 120_0602

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (35-55 m water depths) was mosaiced from acoustic data collected in 2006 aboard the R/V Tatoosh. A Klein System 3000...

  12. Olympic Coast National Marine Sanctuary - mos122_0702.tif - Side scan sonar mosaic from survey effort 122_0702.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (15-35 m water depths) was mosaiced from acoustic data collected in 2007 aboard the R/V Tatoosh. A Klein System 3000...

  13. Analysis of a new unidimensional model and lateral vibrations of 1-3 piezocomposite side scan sonar array

    CSIR Research Space (South Africa)

    Shatalov, MY

    2006-01-01

    Full Text Available . Lamb modes of the 1-3 piezocomposites are investigated in term of the Certon-Patat membrane model by means of direct variational method application. A new design of a 1-3 piezocomposite side scan SONAR array is considered. An implementation of the array...

  14. Assessment of directionality performances: comparison between Freedom and CP810 sound processors.

    Science.gov (United States)

    Razza, Sergio; Albanese, Greta; Ermoli, Lucilla; Zaccone, Monica; Cristofari, Eliana

    2013-10-01

    To compare speech recognition in noise for the Nucleus Freedom and CP810 sound processors using different directional settings among those available in the SmartSound portfolio. Single-subject, repeated measures study. Tertiary care referral center. Thirty-one monoaurally and binaurally implanted subjects (24 children and 7 adults) were enrolled. They were all experienced Nucleus Freedom sound processor users and achieved a 100% open set word recognition score in quiet listening conditions. Each patient was fitted with the Freedom and the CP810 processor. The program setting incorporated Adaptive Dynamic Range Optimization (ADRO) and adopted the directional algorithm BEAM (both devices) and ZOOM (only on CP810). Speech reception threshold (SRT) was assessed in a free-field layout, with disyllabic word list and interfering multilevel babble noise in the 3 different pre-processing configurations. On average, CP810 improved significantly patients' SRTs as compared to Freedom SP after 1 hour of use. Instead, no significant difference was observed in patients' SRT between the BEAM and the ZOOM algorithm fitted in the CP810 processor. The results suggest that hardware developments achieved in the design of CP810 allow an immediate and relevant directional advantage as compared to the previous-generation Freedom device.

  15. Okeanos Explorer (EX1701): Kingman/Palmyra, Jarvis (Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen...

  16. Severity of Expert-Identified Behavioural Responses of Humpback Whale, Minke Whale, and Northern Bottlenose Whale to Naval Sonar

    NARCIS (Netherlands)

    Sivle, L.D.; Kvadsheim, P.H.; Cure, C.; Isojunno, S.; Wensveen, P.J.; Lam, F.P.A.; Visser, F.; Kleivane, L.; Tyack, P.L.; Harris, C.M.; Miller, P.J.O.

    2015-01-01

    Controlled exposure experiments using 1 to2 kHz sonar signals were conducted with 11 humpback whales (Megaptera novaeangliae), one minke whale (Balaenoptera acutorostrata), and one northern bottlenose whale (Hyperoodon ampullatus) during three field trials from 2011 to 2013. Ship approaches without

  17. Natural and anthropogenic events influence the soundscapes of four bays on Hawaii Island.

    Science.gov (United States)

    Heenehan, Heather L; Van Parijs, Sofie M; Bejder, Lars; Tyne, Julian A; Southall, Brandon L; Southall, Hugh; Johnston, David W

    2017-11-15

    The soundscapes of four bays along the Kona Coast of Hawaii Island were monitored between January 2011 and March 2013. Equivalent, unweighted sound pressure levels within standard 1/3rd-octave bands (dB re: 1μPa) were calculated for each recording. Sound levels increased at night and were lowest during the daytime when spinner dolphins use the bays to rest. A tsunami provided an opportunity to monitor the soundscape with little anthropogenic component. We detected a decrease in sound levels and variability in one of the busiest bays. During the daytime in the 3.15kHz 1/3rd octave band, we detected 92 loud outliers from vessels, aquaculture, and military mid-frequency active sonar. During one military mid-frequency active sonar event sound levels reached 45.8dB above median ambient noise levels. The differences found in the bays illustrate the importance of understanding soundscapes to effectively manage noise pollution in marine ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Distribution of surficial sediment in Long Island Sound and adjacent waters: Texture and total organic carbon

    Science.gov (United States)

    Poppe, L.J.; Knebel, H.J.; Mlodzinska, Z.J.; Hastings, M.E.; Seekins, B.A.

    2000-01-01

    The surficial sediment distribution within Long Island Sound has been mapped and described using bottom samples, photography, and sidescan sonar, combined with information from the geologic literature. The distributions of sediment type and total organic carbon (TOC) reveal several broad trends that are largely related to the sea-floor geology, the bathymetry, and the effects of modern tidal- and wind-driven currents. Sediment types are most heterogeneous in bathymetrically complex and shallow nearshore areas; the heterogeneity diminishes and the texture fines with decreasing bottom-current energy. Lag deposits of gravel and gravelly sand dominate the surficial sediment texture in areas where bottom currents are the strongest (such as where tidal flow is constricted) and where glacial till crops out at the sea floor. Sand is the dominant sediment type in areas characterized by active sediment transport and in shallow areas affected by fine-grained winnowing. Silty sand and sand-silt-clay mark transitions within the basin from higher- to lower-energy environments, suggesting a diminished hydraulic ability to sort and transport sediment. Clayey silt and silty clay are the dominant sediment types accumulating in the central and western basins and in other areas characterized by long-term depositional environments. The amount of TOC in the sediments of Long Island Sound varies inversely with sediment grain size. Concentrations average more than 1.9% (dry weight) in clayey silt, but are less than 0.4% in sand. Generally, values for TOC increase both toward the west in the Sound and from the shallow margins to the deeper parts of the basin floor. Our data also suggest that TOC concentrations can vary seasonally.

  19. Bubble Clouds and their Transport within the Surf Zone as Measured with a Distributed Array of Upward-Looking Sonars

    National Research Council Canada - National Science Library

    Dahl, Peter

    2000-01-01

    ... in the surf zone and the effects of these bubbles on acoustic propagation. This paper discusses data gathered by the Applied Physics Laboratory, University of Washington, using a set of four upward-looking sonars (frequency 240 kHz...

  20. Oscillations of end loaded cantilever beams

    International Nuclear Information System (INIS)

    Macho-Stadler, E; Elejalde-García, M J; Llanos-Vázquez, R

    2015-01-01

    This article presents several simple experiments based on changing transverse vibration frequencies in a cantilever beam, when acted on by an external attached mass load at the free end. By using a mechanical wave driver, available in introductory undergraduate laboratories, we provide various experimental results for end loaded cantilever beams that fit reasonably well into a linear equation. The behaviour of the cantilever beam’s weak-damping resonance response is studied for the case of metal resonance strips. As the mass load increases, a more pronounced decrease occurs in the fundamental frequency of beam vibration. It is important to note that cantilever construction is often used in architectural design and engineering construction projects but current analysis also predicts the influence of mass load on the sound generated by musical free reeds with boundary conditions similar to a cantilever beam. (paper)

  1. Oscillations of end loaded cantilever beams

    Science.gov (United States)

    Macho-Stadler, E.; Elejalde-García, M. J.; Llanos-Vázquez, R.

    2015-09-01

    This article presents several simple experiments based on changing transverse vibration frequencies in a cantilever beam, when acted on by an external attached mass load at the free end. By using a mechanical wave driver, available in introductory undergraduate laboratories, we provide various experimental results for end loaded cantilever beams that fit reasonably well into a linear equation. The behaviour of the cantilever beam’s weak-damping resonance response is studied for the case of metal resonance strips. As the mass load increases, a more pronounced decrease occurs in the fundamental frequency of beam vibration. It is important to note that cantilever construction is often used in architectural design and engineering construction projects but current analysis also predicts the influence of mass load on the sound generated by musical free reeds with boundary conditions similar to a cantilever beam.

  2. Acoustic modelling and simulation of next generation torpedoes.

    NARCIS (Netherlands)

    Schippers, P.; Benders, F.P.A.

    2003-01-01

    Since 1987 sonar performance modelling is developed at TNO Physics and Electronics Laboratory. This is based on propagation modelling in a given environment together with modelling of the sonar based on its specific parameters. Beam forming, pulse type and signal processing are taken into account.

  3. Detection and Classification of Marine mammals using an LFAS system

    NARCIS (Netherlands)

    IJsselmuide, S.P. van; Beerend, S.P.

    2004-01-01

    World wide a concern is emerging about the influence of man-made sound in the sea on marine life, and particularly about high power active sonars systems. Most concern lies with marine mammals, which fully depend on sound in their natural behaviour (foraging, navigation and communication). One of

  4. Sound algorithms

    OpenAIRE

    De Götzen , Amalia; Mion , Luca; Tache , Olivier

    2007-01-01

    International audience; We call sound algorithms the categories of algorithms that deal with digital sound signal. Sound algorithms appeared in the very infancy of computer. Sound algorithms present strong specificities that are the consequence of two dual considerations: the properties of the digital sound signal itself and its uses, and the properties of auditory perception.

  5. 46 CFR 7.20 - Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and...

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and easterly entrance to Long Island Sound, NY. 7.20 Section 7.20... Atlantic Coast § 7.20 Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island...

  6. Impact of bathymetric system advances on hydrography

    Digital Repository Service at National Institute of Oceanography (India)

    Ranade, G.

    undergone unprecedented changes with the advancement in the motion sensor technology. By late 1970 gyro stabilized accelerometer based attitude monitoring systems, computing roll, pitch and heave sensing and came in to existence. Doppler sonar principle...). “Multibeam bathymetric sonar: Sea Beam and Hydrochart”, Mar. Geod., vol. 4, pp.77-93. 4. Urick, R. (1975), “Principles of Underwater Acoustics”, McGraw – Hill. 5. Christian de Moustier, C. (1987). “Online Sea Beam acoustic imaging, Proc. Oceans ‘87...

  7. Passive synthetic aperture sonar techniques in combination with tow ship noise canceling: application to a triplet towed array

    NARCIS (Netherlands)

    Colin, M.E.G.D.; Groen, J.

    2002-01-01

    An important issue in research on passive ASW operations is improvement in signal-to-noise ratio (SNR) and bearing resolution for targets emitting low frequency signals. One of the techniques believed to improve these characteristics is Synthetic Aperture Sonar (SAS). The method is based on the

  8. Operationele Oceanografie en Rapid Environmental Assessment (Operational Oceanography and Rapid Environmental Assessment)

    National Research Council Canada - National Science Library

    te Raa, L. A; Lam, F. P; Schouten, M. W

    2008-01-01

    .... Possible applications of operational oceanography in REA include improved sonar performance predictions with three-dimensional sound speed forecasts, support of AUV mission planning with the help...

  9. An approach towards solving refraction problems in EM1002 multi-beam echo-sounder system

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, W.A.

    Multi-beam echo-sounding is the technique in which multiple beams of acoustic in nature are sent down to seabed and upon reflection, they are received back and processed to give depths values. The report is focused to give a brief idea about EM1002...

  10. Automatic Target Recognition in Synthetic Aperture Sonar Images Based on Geometrical Feature Extraction

    Directory of Open Access Journals (Sweden)

    J. Del Rio Vera

    2009-01-01

    Full Text Available This paper presents a new supervised classification approach for automated target recognition (ATR in SAS images. The recognition procedure starts with a novel segmentation stage based on the Hilbert transform. A number of geometrical features are then extracted and used to classify observed objects against a previously compiled database of target and non-target features. The proposed approach has been tested on a set of 1528 simulated images created by the NURC SIGMAS sonar model, achieving up to 95% classification accuracy.

  11. Algorithms and data structures for automated change detection and classification of sidescan sonar imagery

    Science.gov (United States)

    Gendron, Marlin Lee

    During Mine Warfare (MIW) operations, MIW analysts perform change detection by visually comparing historical sidescan sonar imagery (SSI) collected by a sidescan sonar with recently collected SSI in an attempt to identify objects (which might be explosive mines) placed at sea since the last time the area was surveyed. This dissertation presents a data structure and three algorithms, developed by the author, that are part of an automated change detection and classification (ACDC) system. MIW analysts at the Naval Oceanographic Office, to reduce the amount of time to perform change detection, are currently using ACDC. The dissertation introductory chapter gives background information on change detection, ACDC, and describes how SSI is produced from raw sonar data. Chapter 2 presents the author's Geospatial Bitmap (GB) data structure, which is capable of storing information geographically and is utilized by the three algorithms. This chapter shows that a GB data structure used in a polygon-smoothing algorithm ran between 1.3--48.4x faster than a sparse matrix data structure. Chapter 3 describes the GB clustering algorithm, which is the author's repeatable, order-independent method for clustering. Results from tests performed in this chapter show that the time to cluster a set of points is not affected by the distribution or the order of the points. In Chapter 4, the author presents his real-time computer-aided detection (CAD) algorithm that automatically detects mine-like objects on the seafloor in SSI. The author ran his GB-based CAD algorithm on real SSI data, and results of these tests indicate that his real-time CAD algorithm performs comparably to or better than other non-real-time CAD algorithms. The author presents his computer-aided search (CAS) algorithm in Chapter 5. CAS helps MIW analysts locate mine-like features that are geospatially close to previously detected features. A comparison between the CAS and a great circle distance algorithm shows that the

  12. On Estimation Of The Orientation Of Mobile Robots Using Turning Functions And SONAR Information

    Directory of Open Access Journals (Sweden)

    Dorel AIORDACHIOAIE

    2003-12-01

    Full Text Available SONAR systems are widely used by some artificial objects, e.g. robots, and by animals, e.g. bats, for navigation and pattern recognition. The objective of this paper is to present a solution on the estimation of the orientation in the environment of mobile robots, in the context of navigation, using the turning function approach. The results are shown to be accurate and can be used further in the design of navigation strategies of mobile robots.

  13. Effect of longitudinal vibration of fluid-filled pipe with elastic wall on sound transmission character

    Directory of Open Access Journals (Sweden)

    DONG Peng

    2017-01-01

    Full Text Available When one end of a fluid-filled pipe with an elastic wall is fixed and a harmonic force effect acts on the other end,a steady longitudinal vibration will be produced. Compared to the pipeline resonance mode,the amplitude of the steady longitudinal vibration of an elastic pipe is greater,and the effect on the sound is also greater. The study of the steady longitudinal vibration of pipes can better describe the effects of fluid-filled pipelines on the radiation sound field of the pipe opening. Through the contrast between the analysis calculation of the equivalent beam model and the experimental results,the accuracy of the equivalent beam model for the calculation of the steady longitudinal vibration of pipelines is verified,and a method of isolating the steady longitudinal vibration state is proposed and verified.

  14. Discrimination of Cylinders with Different Wall Thicknesses using Neural Networks and Simulated Dolphin Sonar Signals

    DEFF Research Database (Denmark)

    Andersen, Lars Nonboe; Au, Whitlow; Larsen, Jan

    1999-01-01

    This paper describes a method integrating neural networks into a system for recognizing underwater objects. The system is based on a combination of simulated dolphin sonar signals, simulated auditory filters and artificial neural networks. The system is tested on a cylinder wall thickness...... difference experiment and demonstrates high accuracy for small wall thickness differences. Results from the experiment are compared with results obtained by a false killer whale (pseudorca crassidens)....

  15. Statistically sound evaluation of trace element depth profiles by ion beam analysis

    International Nuclear Information System (INIS)

    Schmid, K.; Toussaint, U. von

    2012-01-01

    This paper presents the underlying physics and statistical models that are used in the newly developed program NRADC for fully automated deconvolution of trace level impurity depth profiles from ion beam data. The program applies Bayesian statistics to find the most probable depth profile given ion beam data measured at different energies and angles for a single sample. Limiting the analysis to % level amounts of material allows one to linearize the forward calculation of ion beam data which greatly improves the computation speed. This allows for the first time to apply the maximum likelihood approach to both the fitting of the experimental data and the determination of confidence intervals of the depth profiles for real world applications. The different steps during the automated deconvolution will be exemplified by applying the program to artificial and real experimental data.

  16. On the design and construction of drifting-mine test targets for sonar, radar and electro-optical detection experiments

    NARCIS (Netherlands)

    Dol, H.S.

    2014-01-01

    The timely detection of small hazardous objects at the sea surface, such as drifting mines, is challenging for ship-mounted sensor systems, both for underwater sensor systems like sonar and above-water sensor systems like radar and electro-optics (lidar, infrared/visual cameras). This is due to the

  17. Convergent acoustic field of view in echolocating bats

    DEFF Research Database (Denmark)

    Jakobsen, Lasse; Ratcliffe, John M; Surlykke, Annemarie

    2013-01-01

    Most echolocating bats exhibit a strong correlation between body size and the frequency of maximum energy in their echolocation calls (peak frequency), with smaller species using signals of higher frequency than larger ones. Size-signal allometry or acoustic detection constraints imposed on wavel......Most echolocating bats exhibit a strong correlation between body size and the frequency of maximum energy in their echolocation calls (peak frequency), with smaller species using signals of higher frequency than larger ones. Size-signal allometry or acoustic detection constraints imposed...... on wavelength by preferred prey size have been used to explain this relationship. Here we propose the hypothesis that smaller bats emit higher frequencies to achieve directional sonar beams, and that variable beam width is critical for bats. Shorter wavelengths relative to the size of the emitter translate...... into more directional sound beams. Therefore, bats that emit their calls through their mouths should show a relationship between mouth size and wavelength, driving smaller bats to signals of higher frequency. We found that in a flight room mimicking a closed habitat, six aerial hawking vespertilionid...

  18. Underwater object classification using scattering transform of sonar signals

    Science.gov (United States)

    Saito, Naoki; Weber, David S.

    2017-08-01

    In this paper, we apply the scattering transform (ST)-a nonlinear map based off of a convolutional neural network (CNN)-to classification of underwater objects using sonar signals. The ST formalizes the observation that the filters learned by a CNN have wavelet-like structure. We achieve effective binary classification both on a real dataset of Unexploded Ordinance (UXOs), as well as synthetically generated examples. We also explore the effects on the waveforms with respect to changes in the object domain (e.g., translation, rotation, and acoustic impedance, etc.), and examine the consequences coming from theoretical results for the scattering transform. We show that the scattering transform is capable of excellent classification on both the synthetic and real problems, thanks to having more quasi-invariance properties that are well-suited to translation and rotation of the object.

  19. Mapping nuclear craters on Enewetak Atoll, Marshall Islands

    Science.gov (United States)

    Hampson, John C., Jr.

    1986-01-01

    In 1984, the U.S. Geological Survey conducted a detailed geologic analysis of two nuclear test craters at Enewetak Atoll, Marshall Islands, on behalf of the Defense Nuclear Agency. A multidisciplinary task force mapped the morphology, surface character, and subsurface structure of two craters, OAK and KOA. The field mapping techniques include echo sounding, sidescan sonar imaging, single-channel and multichannel seismic reflection profiling, a seismic refraction survey, and scuba and submersible operations. All operations had to be navigated precisely and correlatable with subsequent drilling and sampling operations. Mapping with a high degree of precision at scales as large as 1:1500 required corrections that often are not considered in marine mapping. Corrections were applied to the bathymetric data for location of the echo- sounding transducer relative to the navigation transponder on the ship and for transducer depth, speed of sound, and tidal variations. Sidescan sonar, single-channel seismic reflection, and scuba and submersible data were correlated in depth and map position with the bathymetric data to provide a precise, internally consistent data set. The multichannel and refraction surveys were conducted independently but compared well with bathymetry. Examples drawn from processing the bathymetric, sidescan sonar, and single- channel reflection data help illustrate problems and procedures in precision mapping.

  20. Plasma density enhancements created by the ionization of the Earth's upper atmosphere by artificial electron beams

    DEFF Research Database (Denmark)

    Neubert, Torsten; Banks, P.M.

    line) and down-going differential energy flux. The equations are solved numerically, using the MSIS atmospheric model and the IRI ionospheric model. The results from the model compare well with recent observations from the CHARGE 2 sounding rocket experiment. Two aspects of the beam-neutral atmosphere...... interaction are discussed: First we investigate the limits on the electron beam current that can be emitted from a space. craft without substantial spacecraft charging. This question is important because the charging of the spacecraft to positive potentials limits the current and the escape energy of the beam...... electrons and thereby limits the ionization of the neutral atmosphere. As an example we find from CHARGE 2 observations and from the model calculations that below about 180 km, secondary electrons generated through the ionization of the neutral atmosphere by 1-10 keV electron beams from sounding rockets...

  1. Leak detection in the primary reactor coolant piping of nuclear power plant by applying beam-microphone technology

    International Nuclear Information System (INIS)

    Kasai, Yoshimitsu; Shimanskiy, Sergey; Naoi, Yosuke; Kanazawa, Junichi

    2004-01-01

    A microphone leak detection method was applied to the inlet piping of the ATR-prototype reactor, Fugen. Statistical analysis results showed that the cross-correlation method provided the effective results for detection of a small leakage. However, such a technique has limited application due to significant distortion of the signals on the reactor site. As one of the alternative methods, the beam-microphone provides necessary spatial selectivity and its performance is less affected by signal distortion. A prototype of the beam-microphone was developed and then tested at the O-arai Engineering Center of the Japan Nuclear Cycle Development Institute (JNC). On-site testing of the beam-microphone was carried out in the inlet piping room of an RBMK reactor of the Leningrad Nuclear Power Plant (LNPP) in Russia. A leak sound imitator was used to simulate the leakage sound under the leakage flow condition of 1-3 gpm (0.23-0.7 m 3 /h). Analysis showed that signal distortion does not seriously affect the performance of this method, and that sound reflection may result in the appearance of ghost sound sources. The test results showed that the influences of sound reflection and background noise were smaller at the high frequencies where the leakage location could be estimated with an angular accuracy of 5deg which is the range of localization accuracy required for the leak detection system. (author)

  2. Assessment of bridge scour in the lower, middle, and upper Yangtze River estuary with riverbed sonar profiling techniques.

    Science.gov (United States)

    Zheng, Shuwei; Xu, Y Jun; Cheng, Heqin; Wang, Bo; Lu, Xuejun

    2017-12-12

    Riverbed scour of bridge piers can cause rapid loss in foundation strength, leading to sudden bridge collapse. This study used multi-beam echo sounders (Seabat 7125) to map riverbed surrounding the foundations of four major bridges in the lower, middle, and upper reaches of the 700-km Yangtze River Estuary (YRE) during June 2015 and September 2016. The high-resolution data were utilized to analyze the morphology of the bridge scour and the deformation of the wide-area riverbed (i.e., 5-18 km long and 1.3-8.3 km wide). In addition, previous bathymetric measurements collected in 1998, 2009, and 2013 were used to determine riverbed erosion and deposition at the bridge reaches. Our study shows that the scour depth surrounding the bridge foundations progressed up to 4.4-19.0 m in the YRE. Over the past 5-15 years, the total channel erosion in some river reaches was up to 15-17 m, possessing a threat to the bridge safety in the YRE. Tide cycles seemed to have resulted in significant variation in the scour morphology in the lower and middle YRE. In the lower YRE, the riverbed morphology displayed one long erosional ditch on both sides of the bridge foundations and a long-strip siltation area distributed upstream and downstream of the bridge foundations; in the middle YRE, the riverbed morphology only showed erosional morphology surrounding the bridge foundations. Large dunes caused deep cuts and steeper contours in the bridge scour. Furthermore, this study demonstrates that the high-resolution grid model formed by point cloud data of multi-beam echo sounders can clearly display the morphology of the bridge scour in terms of wide areas and that the sonar technique is a very useful tool in the assessment of bridge scours.

  3. An Adaptive Cultural Algorithm with Improved Quantum-behaved Particle Swarm Optimization for Sonar Image Detection.

    Science.gov (United States)

    Wang, Xingmei; Hao, Wenqian; Li, Qiming

    2017-12-18

    This paper proposes an adaptive cultural algorithm with improved quantum-behaved particle swarm optimization (ACA-IQPSO) to detect the underwater sonar image. In the population space, to improve searching ability of particles, iterative times and the fitness value of particles are regarded as factors to adaptively adjust the contraction-expansion coefficient of the quantum-behaved particle swarm optimization algorithm (QPSO). The improved quantum-behaved particle swarm optimization algorithm (IQPSO) can make particles adjust their behaviours according to their quality. In the belief space, a new update strategy is adopted to update cultural individuals according to the idea of the update strategy in shuffled frog leaping algorithm (SFLA). Moreover, to enhance the utilization of information in the population space and belief space, accept function and influence function are redesigned in the new communication protocol. The experimental results show that ACA-IQPSO can obtain good clustering centres according to the grey distribution information of underwater sonar images, and accurately complete underwater objects detection. Compared with other algorithms, the proposed ACA-IQPSO has good effectiveness, excellent adaptability, a powerful searching ability and high convergence efficiency. Meanwhile, the experimental results of the benchmark functions can further demonstrate that the proposed ACA-IQPSO has better searching ability, convergence efficiency and stability.

  4. Applicability of neutrino beams to Earth exploration

    International Nuclear Information System (INIS)

    Dolgoshein, B.A.; Kalinovskij, A.N.

    1985-01-01

    The projects on applicability of neutrino beams from high energy accelerators for geological exploration and study of the Earth structure are discussed. The GENIUS (Geological Exploration by Neutrino Induced Underground Sound) project is among them. It covers detecting and studying space-time characteristics of acoustic signal arising in case of neutrino interaction with Earth depth rocks discussed. The GEMINI (Geological Exploration with Muons Induced by neutrino interactions) project represents one more possibility for using geotron neutrino beam for the purpose of geological exploration. The GEOSCAN project represents the possibility for applying high energy neutrino beams for the purpose of the Earth translusence to determine the changes in the density of internal part of the Earth. The necessity of detailed investigations of the problem of applicability of neutrino beams in the field of the Earth exploration is pointed out

  5. PREFACE: Aerodynamic sound Aerodynamic sound

    Science.gov (United States)

    Akishita, Sadao

    2010-02-01

    The modern theory of aerodynamic sound originates from Lighthill's two papers in 1952 and 1954, as is well known. I have heard that Lighthill was motivated in writing the papers by the jet-noise emitted by the newly commercialized jet-engined airplanes at that time. The technology of aerodynamic sound is destined for environmental problems. Therefore the theory should always be applied to newly emerged public nuisances. This issue of Fluid Dynamics Research (FDR) reflects problems of environmental sound in present Japanese technology. The Japanese community studying aerodynamic sound has held an annual symposium since 29 years ago when the late Professor S Kotake and Professor S Kaji of Teikyo University organized the symposium. Most of the Japanese authors in this issue are members of the annual symposium. I should note the contribution of the two professors cited above in establishing the Japanese community of aerodynamic sound research. It is my pleasure to present the publication in this issue of ten papers discussed at the annual symposium. I would like to express many thanks to the Editorial Board of FDR for giving us the chance to contribute these papers. We have a review paper by T Suzuki on the study of jet noise, which continues to be important nowadays, and is expected to reform the theoretical model of generating mechanisms. Professor M S Howe and R S McGowan contribute an analytical paper, a valuable study in today's fluid dynamics research. They apply hydrodynamics to solve the compressible flow generated in the vocal cords of the human body. Experimental study continues to be the main methodology in aerodynamic sound, and it is expected to explore new horizons. H Fujita's study on the Aeolian tone provides a new viewpoint on major, longstanding sound problems. The paper by M Nishimura and T Goto on textile fabrics describes new technology for the effective reduction of bluff-body noise. The paper by T Sueki et al also reports new technology for the

  6. Burial and exhumation of temperate bedrock reefs as elucidated by repetitive high-resolution sea floor sonar surveys: Spatial patterns and impacts to species' richness and diversity

    Science.gov (United States)

    Storlazzi, Curt D.; Fregoso, Theresa A.; Figurski, Jared D.; Freiwald, Jan; Lonhart, Steve I.; Finlayson, David P.

    2013-01-01

    To understand how chronic sediment burial and scour contribute to variation in the structure of algal and invertebrate communities on temperate bedrock reefs, the dynamics of the substrate and communities were monitored at locations that experience sand inundation and adjacent areas that do not. Co-located benthic scuba-transect surveys and high-resolution swath-sonar surveys were completed on bedrock reefs on the inner shelf of northern Monterey Bay, CA, in early winter 2009, spring 2010, and summer 2010. Analysis of the sonar surveys demonstrates that during the 8 months over which the surveys were conducted, 19.6% of the study area was buried by sand while erosion resulted in the exposure of bedrock over 13.8% of the study area; the remainder underwent no change between the surveys. Substrate classifications from the benthic transect surveys correlated with classifications generated from the sonar surveys, demonstrating the capacity of high-resolution sonar surveys to detect burial of bedrock reefs by sediment. On bedrock habitat that underwent burial and exhumation, species' diversity and richness of rock-associated sessile and mobile organisms were 50–66% lower as compared to adjacent stable bedrock habitat. While intermediate levels of disturbance can increase the diversity and richness of communities, these findings demonstrate that burial and exhumation of bedrock habitat are sources of severe disturbance. We suggest that substrate dynamics must be considered when developing predictions of benthic community distributions based on sea floor imagery. These results highlight the need for predictive models of substrate dynamics and for a better understanding of how burial and exhumation shape benthic communities.

  7. Exploring science with sound: sonification and the use of sonograms as data analysis tool

    CERN Multimedia

    CERN. Geneva; Williams, Genevieve

    2017-01-01

    Resonances, periodicity, patterns and spectra are well-known notions that play crucial roles in particle physics, and that have always been at the junction between sound/music analysis and scientific exploration. Detecting the shape of a particular energy spectrum, studying the stability of a particle beam in a synchrotron, and separating signals from a noisy background are just a few examples where the connection with sound can be very strong, all sharing the same concepts of oscillations, cycles and frequency. This seminar will focus on analysing data and their relations by translating measurements into audible signals and using the natural capability of the ear to distinguish, characterise and analyse waveform shapes, amplitudes and relations. This process is called data sonification, and one of the main tools to investigate the structure of the sound is the sonogram (sometimes also called a spectrogram). A sonogram is a visual representation of how the spectrum of a certain sound signal changes with time...

  8. Sonar atlas of caverns comprising the U.S. Strategic Petroleum Reserve. Volume 2, Big Hill Site, Texas.

    Energy Technology Data Exchange (ETDEWEB)

    Rautman, Christopher Arthur; Lord, Anna Snider

    2007-08-01

    Downhole sonar surveys from the four active U.S. Strategic Petroleum Reserve sites have been modeled and used to generate a four-volume sonar atlas, showing the three-dimensional geometry of each cavern. This volume 2 focuses on the Big Hill SPR site, located in southeastern Texas. Volumes 1, 3, and 4, respectively, present images for the Bayou Choctaw SPR site, Louisiana, the Bryan Mound SPR site, Texas, and the West Hackberry SPR site, Louisiana. The atlas uses a consistent presentation format throughout. The basic geometric measurements provided by the down-cavern surveys have also been used to generate a number of geometric attributes, the values of which have been mapped onto the geometric form of each cavern using a color-shading scheme. The intent of the various geometrical attributes is to highlight deviations of the cavern shape from the idealized cylindrical form of a carefully leached underground storage cavern in salt. The atlas format does not allow interpretation of such geometric deviations and anomalies. However, significant geometric anomalies, not directly related to the leaching history of the cavern, may provide insight into the internal structure of the relevant salt dome.

  9. Sonar atlas of caverns comprising the U.S. Strategic Petroleum Reserve. Volume 1, Bayou Choctaw site, Louisiana.

    Energy Technology Data Exchange (ETDEWEB)

    Rautman, Christopher Arthur; Lord, Anna Snider

    2007-10-01

    Downhole sonar surveys from the four active U.S. Strategic Petroleum Reserve sites have been modeled and used to generate a four-volume sonar atlas, showing the three-dimensional geometry of each cavern. This volume 1 focuses on the Bayou Choctaw SPR site, located in southern Louisiana. Volumes 2, 3, and 4, respectively, present images for the Big Hill SPR site, Texas, the Bryan Mound SPR site, Texas, and the West Hackberry SPR site, Louisiana. The atlas uses a consistent presentation format throughout. The basic geometric measurements provided by the down-cavern surveys have also been used to generate a number of geometric attributes, the values of which have been mapped onto the geometric form of each cavern using a color-shading scheme. The intent of the various geometrical attributes is to highlight deviations of the cavern shape from the idealized cylindrical form of a carefully leached underground storage cavern in salt. The atlas format does not allow interpretation of such geometric deviations and anomalies. However, significant geometric anomalies, not directly related to the leaching history of the cavern, may provide insight into the internal structure of the relevant salt dome.

  10. Sonar atlas of caverns comprising the U.S. Strategic Petroleum Reserve. Volume 3, Bryan Mound Site, Texas.

    Energy Technology Data Exchange (ETDEWEB)

    Rautman, Christopher Arthur; Lord, Anna Snider

    2007-09-01

    Downhole sonar surveys from the four active U.S. Strategic Petroleum Reserve sites have been modeled and used to generate a four-volume sonar atlas, showing the three-dimensional geometry of each cavern. This volume 3 focuses on the Bryan Mound SPR site, located in southeastern Texas. Volumes 1, 2, and 4, respectively, present images for the Bayou Choctaw SPR site, Louisiana, the Big Hill SPR site, Texas, and the West Hackberry SPR site, Louisiana. The atlas uses a consistent presentation format throughout. The basic geometric measurements provided by the down-cavern surveys have also been used to generate a number of geometric attributes, the values of which have been mapped onto the geometric form of each cavern using a color-shading scheme. The intent of the various geometrical attributes is to highlight deviations of the cavern shape from the idealized cylindrical form of a carefully leached underground storage cavern in salt. The atlas format does not allow interpretation of such geometric deviations and anomalies. However, significant geometric anomalies, not directly related to the leaching history of the cavern, may provide insight into the internal structure of the relevant salt dome.

  11. Sonar atlas of caverns comprising the U.S. Strategic Petroleum Reserve. Volume 4, West Hackberry site, Louisiana.

    Energy Technology Data Exchange (ETDEWEB)

    Rautman, Christopher Arthur; Lord, Anna Snider

    2007-09-01

    Downhole sonar surveys from the four active U.S. Strategic Petroleum Reserve sites have been modeled and used to generate a four-volume sonar atlas, showing the three-dimensional geometry of each cavern. This volume 4 focuses on the West Hackberry SPR site, located in southwestern Louisiana. Volumes 1, 2, and 3, respectively, present images for the Bayou Choctaw SPR site, Louisiana, the Big Hill SPR site, Texas, and the Bryan Mound SPR site, Texas. The atlas uses a consistent presentation format throughout. The basic geometric measurements provided by the down-cavern surveys have also been used to generate a number of geometric attributes, the values of which have been mapped onto the geometric form of each cavern using a color-shading scheme. The intent of the various geometrical attributes is to highlight deviations of the cavern shape from the idealized cylindrical form of a carefully leached underground storage cavern in salt. The atlas format does not allow interpretation of such geometric deviations and anomalies. However, significant geometric anomalies, not directly related to the leaching history of the cavern, may provide insight into the internal structure of the relevant salt dome.

  12. Imagining Sound

    DEFF Research Database (Denmark)

    Grimshaw, Mark; Garner, Tom Alexander

    2014-01-01

    We make the case in this essay that sound that is imagined is both a perception and as much a sound as that perceived through external stimulation. To argue this, we look at the evidence from auditory science, neuroscience, and philosophy, briefly present some new conceptual thinking on sound...... that accounts for this view, and then use this to look at what the future might hold in the context of imagining sound and developing technology....

  13. Development of Prediction Tool for Sound Absorption and Sound Insulation for Sound Proof Properties

    OpenAIRE

    Yoshio Kurosawa; Takao Yamaguchi

    2015-01-01

    High frequency automotive interior noise above 500 Hz considerably affects automotive passenger comfort. To reduce this noise, sound insulation material is often laminated on body panels or interior trim panels. For a more effective noise reduction, the sound reduction properties of this laminated structure need to be estimated. We have developed a new calculate tool that can roughly calculate the sound absorption and insulation properties of laminate structure and handy ...

  14. Parameterizing Sound: Design Considerations for an Environmental Sound Database

    Science.gov (United States)

    2015-04-01

    associated with, or produced by, a physical event or human activity and 2) sound sources that are common in the environment. Reproductions or sound...Rogers S. Confrontation naming of environmental sounds. Journal of Clinical and Experimental Neuropsychology . 2000;22(6):830–864. 14 VanDerveer NJ

  15. Making fictions sound real - On film sound, perceptual realism and genre

    Directory of Open Access Journals (Sweden)

    Birger Langkjær

    2010-05-01

    Full Text Available This article examines the role that sound plays in making fictions perceptually real to film audiences, whether these fictions are realist or non-realist in content and narrative form. I will argue that some aspects of film sound practices and the kind of experiences they trigger are related to basic rules of human perception, whereas others are more properly explained in relation to how aesthetic devices, including sound, are used to characterise the fiction and thereby make it perceptually real to its audience. Finally, I will argue that not all genres can be defined by a simple taxonomy of sounds. Apart from an account of the kinds of sounds that typically appear in a specific genre, a genre analysis of sound may also benefit from a functionalist approach that focuses on how sounds can make both realist and non-realist aspects of genres sound real to audiences.

  16. Making fictions sound real - On film sound, perceptual realism and genre

    Directory of Open Access Journals (Sweden)

    Birger Langkjær

    2009-09-01

    Full Text Available This article examines the role that sound plays in making fictions perceptually real to film audiences, whether these fictions are realist or non-realist in content and narrative form. I will argue that some aspects of film sound practices and the kind of experiences they trigger are related to basic rules of human perception, whereas others are more properly explained in relation to how aesthetic devices, including sound, are used to characterise the fiction and thereby make it perceptually real to its audience. Finally, I will argue that not all genres can be defined by a simple taxonomy of sounds. Apart from an account of the kinds of sounds that typically appear in a specific genre, a genre analysis of sound may also benefit from a functionalist approach that focuses on how sounds can make both realist and non-realist aspects of genres sound real to audiences.

  17. Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

    International Nuclear Information System (INIS)

    Nerilli, Francesca; Vairo, Giuseppe

    2016-01-01

    In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

  18. Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

    Energy Technology Data Exchange (ETDEWEB)

    Nerilli, Francesca [Unicusano - Università degli Studi Niccolò Cusano Telematica Roma, 00166 Rome (Italy); Vairo, Giuseppe [Università degli Studi di Roma “Tor Vergata”- (DICII), 00133 Rome (Italy)

    2016-06-08

    In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

  19. Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

    Science.gov (United States)

    Nerilli, Francesca; Vairo, Giuseppe

    2016-06-01

    In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

  20. Acoustics of finite asymmetric exotic beams: Examples of Airy and fractional Bessel beams

    Science.gov (United States)

    Mitri, F. G.

    2017-12-01

    hybrid method to analyze quantitatively the scattering, radiation force, and spin torque by any finite asymmetric (or symmetric) acoustic beam with potential applications in various fields of applied physics (such as beam-forming, imaging, and mechanical effects of asymmetric sound beams).

  1. Sound Absorbers

    Science.gov (United States)

    Fuchs, H. V.; Möser, M.

    Sound absorption indicates the transformation of sound energy into heat. It is, for instance, employed to design the acoustics in rooms. The noise emitted by machinery and plants shall be reduced before arriving at a workplace; auditoria such as lecture rooms or concert halls require a certain reverberation time. Such design goals are realised by installing absorbing components at the walls with well-defined absorption characteristics, which are adjusted for corresponding demands. Sound absorbers also play an important role in acoustic capsules, ducts and screens to avoid sound immission from noise intensive environments into the neighbourhood.

  2. Making Sound Connections

    Science.gov (United States)

    Deal, Walter F., III

    2007-01-01

    Sound provides and offers amazing insights into the world. Sound waves may be defined as mechanical energy that moves through air or other medium as a longitudinal wave and consists of pressure fluctuations. Humans and animals alike use sound as a means of communication and a tool for survival. Mammals, such as bats, use ultrasonic sound waves to…

  3. Abnormal sound detection device

    International Nuclear Information System (INIS)

    Yamada, Izumi; Matsui, Yuji.

    1995-01-01

    Only components synchronized with rotation of pumps are sampled from detected acoustic sounds, to judge the presence or absence of abnormality based on the magnitude of the synchronized components. A synchronized component sampling means can remove resonance sounds and other acoustic sounds generated at a synchronously with the rotation based on the knowledge that generated acoustic components in a normal state are a sort of resonance sounds and are not precisely synchronized with the number of rotation. On the other hand, abnormal sounds of a rotating body are often caused by compulsory force accompanying the rotation as a generation source, and the abnormal sounds can be detected by extracting only the rotation-synchronized components. Since components of normal acoustic sounds generated at present are discriminated from the detected sounds, reduction of the abnormal sounds due to a signal processing can be avoided and, as a result, abnormal sound detection sensitivity can be improved. Further, since it is adapted to discriminate the occurrence of the abnormal sound from the actually detected sounds, the other frequency components which are forecast but not generated actually are not removed, so that it is further effective for the improvement of detection sensitivity. (N.H.)

  4. Sound recovery via intensity variations of speckle pattern pixels selected with variance-based method

    Science.gov (United States)

    Zhu, Ge; Yao, Xu-Ri; Qiu, Peng; Mahmood, Waqas; Yu, Wen-Kai; Sun, Zhi-Bin; Zhai, Guang-Jie; Zhao, Qing

    2018-02-01

    In general, the sound waves can cause the vibration of the objects that are encountered in the traveling path. If we make a laser beam illuminate the rough surface of an object, it will be scattered into a speckle pattern that vibrates with these sound waves. Here, an efficient variance-based method is proposed to recover the sound information from speckle patterns captured by a high-speed camera. This method allows us to select the proper pixels that have large variances of the gray-value variations over time, from a small region of the speckle patterns. The gray-value variations of these pixels are summed together according to a simple model to recover the sound with a high signal-to-noise ratio. Meanwhile, our method will significantly simplify the computation compared with the traditional digital-image-correlation technique. The effectiveness of the proposed method has been verified by applying a variety of objects. The experimental results illustrate that the proposed method is robust to the quality of the speckle patterns and costs more than one-order less time to perform the same number of the speckle patterns. In our experiment, a sound signal of time duration 1.876 s is recovered from various objects with time consumption of 5.38 s only.

  5. Sound Search Engine Concept

    DEFF Research Database (Denmark)

    2006-01-01

    Sound search is provided by the major search engines, however, indexing is text based, not sound based. We will establish a dedicated sound search services with based on sound feature indexing. The current demo shows the concept of the sound search engine. The first engine will be realased June...

  6. The sound manifesto

    Science.gov (United States)

    O'Donnell, Michael J.; Bisnovatyi, Ilia

    2000-11-01

    Computing practice today depends on visual output to drive almost all user interaction. Other senses, such as audition, may be totally neglected, or used tangentially, or used in highly restricted specialized ways. We have excellent audio rendering through D-A conversion, but we lack rich general facilities for modeling and manipulating sound comparable in quality and flexibility to graphics. We need coordinated research in several disciplines to improve the use of sound as an interactive information channel. Incremental and separate improvements in synthesis, analysis, speech processing, audiology, acoustics, music, etc. will not alone produce the radical progress that we seek in sonic practice. We also need to create a new central topic of study in digital audio research. The new topic will assimilate the contributions of different disciplines on a common foundation. The key central concept that we lack is sound as a general-purpose information channel. We must investigate the structure of this information channel, which is driven by the cooperative development of auditory perception and physical sound production. Particular audible encodings, such as speech and music, illuminate sonic information by example, but they are no more sufficient for a characterization than typography is sufficient for characterization of visual information. To develop this new conceptual topic of sonic information structure, we need to integrate insights from a number of different disciplines that deal with sound. In particular, we need to coordinate central and foundational studies of the representational models of sound with specific applications that illuminate the good and bad qualities of these models. Each natural or artificial process that generates informative sound, and each perceptual mechanism that derives information from sound, will teach us something about the right structure to attribute to the sound itself. The new Sound topic will combine the work of computer

  7. Unsound Sound

    DEFF Research Database (Denmark)

    Knakkergaard, Martin

    2016-01-01

    This article discusses the change in premise that digitally produced sound brings about and how digital technologies more generally have changed our relationship to the musical artifact, not simply in degree but in kind. It demonstrates how our acoustical conceptions are thoroughly challenged...... by the digital production of sound and, by questioning the ontological basis for digital sound, turns our understanding of the core term substance upside down....

  8. Source Array Support for Continuous Monitoring of Fish Population and Behavior by Instantaneous Continental-Shelf-Scale Imaging Using Ocean-Waveguide Acoustics

    National Research Council Canada - National Science Library

    Rynne, Ed; Gillette, David

    2006-01-01

    ...) Multistatic ASW Capability Enhancement Program (MACE) as the source of underwater sounds to support active bi-static sonar capabilities for monitoring fish populations and behaviors during a September/October 2006 sea test off the coast of Maine...

  9. Early Sound Symbolism for Vowel Sounds

    Directory of Open Access Journals (Sweden)

    Ferrinne Spector

    2013-06-01

    Full Text Available Children and adults consistently match some words (e.g., kiki to jagged shapes and other words (e.g., bouba to rounded shapes, providing evidence for non-arbitrary sound–shape mapping. In this study, we investigated the influence of vowels on sound–shape matching in toddlers, using four contrasting pairs of nonsense words differing in vowel sound (/i/ as in feet vs. /o/ as in boat and four rounded–jagged shape pairs. Crucially, we used reduplicated syllables (e.g., kiki vs. koko rather than confounding vowel sound with consonant context and syllable variability (e.g., kiki vs. bouba. Toddlers consistently matched words with /o/ to rounded shapes and words with /i/ to jagged shapes (p < 0.01. The results suggest that there may be naturally biased correspondences between vowel sound and shape.

  10. Sound Art and Spatial Practices: Situating Sound Installation Art Since 1958

    OpenAIRE

    Ouzounian, Gascia

    2008-01-01

    This dissertation examines the emergence and development ofsound installation art, an under-recognized tradition that hasdeveloped between music, architecture, and media art practicessince the late 1950s. Unlike many musical works, which are concernedwith organizing sounds in time, sound installations organize sounds inspace; they thus necessitate new theoretical and analytical modelsthat take into consideration the spatial situated-ness of sound. Existingdiscourses on “spatial sound” privile...

  11. Monitoring the US ATLAS Network Infrastructure with perfSONAR-PS

    CERN Document Server

    McKee, S; The ATLAS collaboration; Laurens, P; Severini, H; Wlodek, T; Wolff, S; Zurawski, J

    2012-01-01

    Global scientific collaborations, such as ATLAS, continue to push the network requirements envelope. Data movement in this collaboration is routinely including the regular exchange of petabytes of datasets between the collection and analysis facilities in the coming years. These requirements place a high emphasis on networks functioning at peak efficiency and availability; the lack thereof could mean critical delays in the overall scientific progress of distributed data-intensive experiments like ATLAS. Network operations staff routinely must deal with problems deep in the infrastructure; this may be as benign as replacing a failing piece of equipment, or as complex as dealing with a multidomain path that is experiencing data loss. In either case, it is crucial that effective monitoring and performance analysis tools are available to ease the burden of management. We will report on our experiences deploying and using the perfSONAR-PS Performance Toolkit[8] at ATLAS sites in the United States. This software cr...

  12. Object Classification in Semi Structured Enviroment Using Forward-Looking Sonar

    Directory of Open Access Journals (Sweden)

    Matheus dos Santos

    2017-09-01

    Full Text Available The submarine exploration using robots has been increasing in recent years. The automation of tasks such as monitoring, inspection, and underwater maintenance requires the understanding of the robot’s environment. The object recognition in the scene is becoming a critical issue for these systems. On this work, an underwater object classification pipeline applied in acoustic images acquired by Forward-Looking Sonar (FLS are studied. The object segmentation combines thresholding, connected pixels searching and peak of intensity analyzing techniques. The object descriptor extract intensity and geometric features of the detected objects. A comparison between the Support Vector Machine, K-Nearest Neighbors, and Random Trees classifiers are presented. An open-source tool was developed to annotate and classify the objects and evaluate their classification performance. The proposed method efficiently segments and classifies the structures in the scene using a real dataset acquired by an underwater vehicle in a harbor area. Experimental results demonstrate the robustness and accuracy of the method described in this paper.

  13. Bending of electromagnetic beams and head-tail radio sources

    Energy Technology Data Exchange (ETDEWEB)

    Bodo, G; Ferrari, A; Massaglia, S [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Turin Univ. (Italy). Ist. di Fisica)

    1981-08-01

    An interpretation is presented of bridge bending in head-tail radio sources in the framework of an electromagnetic beam model. The physical effect responsible for the structural distortion is proposed to be the refraction of a large-amplitude wave in a medium with a density gradient perpendicular to the wave propagation vector; this gradient is consistently produced by the relative motion of the beam source in the surrounding medium with a velocity higher than the speed of sound. These effects are calculated in some detail and a quantitative fit of model parameters to the typical radio source associated with NGC 1265 is discussed.

  14. Sound a very short introduction

    CERN Document Server

    Goldsmith, Mike

    2015-01-01

    Sound is integral to how we experience the world, in the form of noise as well as music. But what is sound? What is the physical basis of pitch and harmony? And how are sound waves exploited in musical instruments? Sound: A Very Short Introduction looks at the science of sound and the behaviour of sound waves with their different frequencies. It also explores sound in different contexts, covering the audible and inaudible, sound underground and underwater, acoustic and electronic sound, and hearing in humans and animals. It concludes with the problem of sound out of place—noise and its reduction.

  15. Ultrasound beam characteristics of a symmetric nodal origami based array

    Science.gov (United States)

    Bilgunde, Prathamesh N.; Bond, Leonard J.

    2018-04-01

    Origami-the ancient art of paper folding-is being explored in acoustics for effective focusing of sound. In this short communication, we present a numerical investigation of beam characteristics for an origami based ultrasound array. A spatial re-configuration of array elements is performed based upon the symmetric nodal origami. The effect of fold angle on the ultrasound beam is evaluated using frequency domain and transient finite element analysis. It was found that increase in the fold angle reduces near field length by 58% and also doubles the beam intensity as compared to the linear array. Transient analysis also indicated 80% reduction in the -6dB beam width, which can improve the lateral resolution of phased array. Such a spatially re-configurable array could potentially be used in the future to reduce the cost of electronics in the phased array instrumentation.

  16. What is Sound?

    OpenAIRE

    Nelson, Peter

    2014-01-01

    What is sound? This question is posed in contradiction to the every-day understanding that sound is a phenomenon apart from us, to be heard, made, shaped and organised. Thinking through the history of computer music, and considering the current configuration of digital communi-cations, sound is reconfigured as a type of network. This network is envisaged as non-hierarchical, in keeping with currents of thought that refuse to prioritise the human in the world. The relationship of sound to musi...

  17. Broadcast sound technology

    CERN Document Server

    Talbot-Smith, Michael

    1990-01-01

    Broadcast Sound Technology provides an explanation of the underlying principles of modern audio technology. Organized into 21 chapters, the book first describes the basic sound; behavior of sound waves; aspects of hearing, harming, and charming the ear; room acoustics; reverberation; microphones; phantom power; loudspeakers; basic stereo; and monitoring of audio signal. Subsequent chapters explore the processing of audio signal, sockets, sound desks, and digital audio. Analogue and digital tape recording and reproduction, as well as noise reduction, are also explained.

  18. Propagation of sound

    DEFF Research Database (Denmark)

    Wahlberg, Magnus; Larsen, Ole Næsbye

    2017-01-01

    properties can be modified by sound absorption, refraction, and interference from multi paths caused by reflections.The path from the source to the receiver may be bent due to refraction. Besides geometrical attenuation, the ground effect and turbulence are the most important mechanisms to influence...... communication sounds for airborne acoustics and bottom and surface effects for underwater sounds. Refraction becomes very important close to shadow zones. For echolocation signals, geometric attenuation and sound absorption have the largest effects on the signals....

  19. mos113_0401r.tif -- Side scan sonar image from survey effort HMPR-113-2004-01r in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (50-80 m water depths) was mosaiced from acoustic data collected in 2004 aboard the NOAA ship McArthurII.A Klein System...

  20. mos119_0601c.tif-- Side scan sonar image from survey effort HMPR-119-2006-01c in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (120-210 m water depths) was mosaiced from acoustic data collected in April 2006 aboard the NOAA ship McArthurII. A...

  1. mos113_0401d.tif -- Side scan sonar image from survey effort HMPR-113-2004-01d in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (120-350 m water depths) was mosaiced from acoustic data collected in 2004 aboard the NOAA ship McArthurII. A Klein...

  2. mos114_0402b.tif -- Side scan sonar image from survey effort HMPR-114-2004-02b in the Olympic Coast National Marine Sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar image of the sea floor was mosaiced from data collected in August 2004 onboard the NOAA vesselTatoosh. An EG&G 272 side scan system was used...

  3. mos119_0601a.tif-- Side scan sonar image from survey effort HMPR-119-2006-01a in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (90-270 m water depths) was mosaiced from acoustic data collected in April 2006 aboard the NOAA ship McArthurII.A Klein...

  4. mos118_0503a.tif -- Side scan sonar image from survey effort HMPR-118-2005-03a in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar imagery of the sea floor (140-350 m water depths) was mosaiced from acoustic data collected in 2005 aboard the NOAA ship McArthurII. A Klein...

  5. The relation between Arctic sea ice surface elevation and draft: A case study using coincident AUV sonar and airborne scanning laser

    DEFF Research Database (Denmark)

    Doble, Martin J.; Skourup, Henriette; Wadhams, Peter

    2011-01-01

    Data are presented from a survey by airborne scanning laser profilometer and an AUV-mounted, upward looking swath sonar in the spring Beaufort Sea. The air-snow (surface elevation) and water-ice (draft) surfaces were mapped at 1 x 1 m resolution over a 300 x 300 m area. Data were separated into l...

  6. Making fictions sound real

    DEFF Research Database (Denmark)

    Langkjær, Birger

    2010-01-01

    This article examines the role that sound plays in making fictions perceptually real to film audiences, whether these fictions are realist or non-realist in content and narrative form. I will argue that some aspects of film sound practices and the kind of experiences they trigger are related...... to basic rules of human perception, whereas others are more properly explained in relation to how aesthetic devices, including sound, are used to characterise the fiction and thereby make it perceptually real to its audience. Finally, I will argue that not all genres can be defined by a simple taxonomy...... of sounds. Apart from an account of the kinds of sounds that typically appear in a specific genre, a genre analysis of sound may also benefit from a functionalist approach that focuses on how sounds can make both realist and non-realist aspects of genres sound real to audiences....

  7. Sound sensitivity of neurons in rat hippocampus during performance of a sound-guided task

    Science.gov (United States)

    Vinnik, Ekaterina; Honey, Christian; Schnupp, Jan; Diamond, Mathew E.

    2012-01-01

    To investigate how hippocampal neurons encode sound stimuli, and the conjunction of sound stimuli with the animal's position in space, we recorded from neurons in the CA1 region of hippocampus in rats while they performed a sound discrimination task. Four different sounds were used, two associated with water reward on the right side of the animal and the other two with water reward on the left side. This allowed us to separate neuronal activity related to sound identity from activity related to response direction. To test the effect of spatial context on sound coding, we trained rats to carry out the task on two identical testing platforms at different locations in the same room. Twenty-one percent of the recorded neurons exhibited sensitivity to sound identity, as quantified by the difference in firing rate for the two sounds associated with the same response direction. Sensitivity to sound identity was often observed on only one of the two testing platforms, indicating an effect of spatial context on sensory responses. Forty-three percent of the neurons were sensitive to response direction, and the probability that any one neuron was sensitive to response direction was statistically independent from its sensitivity to sound identity. There was no significant coding for sound identity when the rats heard the same sounds outside the behavioral task. These results suggest that CA1 neurons encode sound stimuli, but only when those sounds are associated with actions. PMID:22219030

  8. Acoustically-Equipped Ocean Gliders for Environmental and Oceanographic Research

    Science.gov (United States)

    2015-09-30

    operations, including use of tactical sonars, have been linked to marine mammal strandings and fatalities ( Barlow and Gisiner, 2006), particularly of...REFERENCES Barlow , J., and R. Gisiner. 2006. Mitigating, monitoring, and assessing the effects of anthropogenic sound on beaked whales. J

  9. Detection to the DepositFan Occurring in the Sun Moon Lake Using Geophysical Sonar Data

    Science.gov (United States)

    Mimi, L.

    2014-12-01

    Located in central Taiwan, the Sun Moon Lake is an U-shaped basin with the waters capacity for 138.68 × 106m³. The water is input through two underground tunnels from the Wu-Jie dam in the upstream of the Zhuo-shui river. Although the Wu-Jie dam has been trying to keep the tunnels transporting clean water into the lake, the water is still mixed with muds. The silty water brings the deposits accumulating outwards from positions of the tunnel outlets resulting in a deposit fan formed in the lake. To monitor how the fan is accumulated is then very important in terms of environmental issue, tourism and electric power resources. Institute of Oceanography, National Taiwan University therefore conducted projects to use the multi-beam echo sounders to collect bathymetric data, and used the Chirp sub-bottom profiler to explore silted pattern inside the deposit fan. With these data, underwater topographic maps were plotted to observe the shape and internal structure of the fan. Moreover, two sets of data obtained in 2006 and 2012 were used to estimate the siltation magnitude and pattern in the six years period.The multi-beam sounder is Resons Seabat 9001s model; it collects 60 values in each of the swaths positioned by the DGPS method.The sub-bottom profiler is the EdgeTech 3100P Chirp Sonar, its acoustic wave frequency is in 2 ~ 16kHz. The data give the siltation amount in the Sun Moon Lake was around 3× 106 m³, which gives annual siltation rate at 5× 105 m³. The leading edge of the deposit fan has been expanded westwards 2 km from the water outlet since the tunnel was built 70 years ago; however, outside the deposit fan, the siltation shows insignificant amount on the water bottom.In the past few years the siltation mainly occurs outside in the east side of lake, more closer to the water outlets, the terrain had been increased from 744 m to 746 m (748.5 meters is stranded level of the lake).Observing sub-bottom profiler data, we can clearly see the location of the

  10. Memory for product sounds: the effect of sound and label type.

    Science.gov (United States)

    Ozcan, Elif; van Egmond, René

    2007-11-01

    The (mnemonic) interactions between auditory, visual, and the semantic systems have been investigated using structurally complex auditory stimuli (i.e., product sounds). Six types of product sounds (air, alarm, cyclic, impact, liquid, mechanical) that vary in spectral-temporal structure were presented in four label type conditions: self-generated text, text, image, and pictogram. A memory paradigm that incorporated free recall, recognition, and matching tasks was employed. The results for the sound type suggest that the amount of spectral-temporal structure in a sound can be indicative for memory performance. Findings related to label type suggest that 'self' creates a strong bias for the retrieval and the recognition of sounds that were self-labeled; the density and the complexity of the visual information (i.e., pictograms) hinders the memory performance ('visual' overshadowing effect); and image labeling has an additive effect on the recall and matching tasks (dual coding). Thus, the findings suggest that the memory performances for product sounds are task-dependent.

  11. 33 CFR 167.1702 - In Prince William Sound: Prince William Sound Traffic Separation Scheme.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false In Prince William Sound: Prince William Sound Traffic Separation Scheme. 167.1702 Section 167.1702 Navigation and Navigable Waters COAST....1702 In Prince William Sound: Prince William Sound Traffic Separation Scheme. The Prince William Sound...

  12. Sounds Exaggerate Visual Shape

    Science.gov (United States)

    Sweeny, Timothy D.; Guzman-Martinez, Emmanuel; Ortega, Laura; Grabowecky, Marcia; Suzuki, Satoru

    2012-01-01

    While perceiving speech, people see mouth shapes that are systematically associated with sounds. In particular, a vertically stretched mouth produces a /woo/ sound, whereas a horizontally stretched mouth produces a /wee/ sound. We demonstrate that hearing these speech sounds alters how we see aspect ratio, a basic visual feature that contributes…

  13. Sound Zones

    DEFF Research Database (Denmark)

    Møller, Martin Bo; Olsen, Martin

    2017-01-01

    Sound zones, i.e. spatially confined regions of individual audio content, can be created by appropriate filtering of the desired audio signals reproduced by an array of loudspeakers. The challenge of designing filters for sound zones is twofold: First, the filtered responses should generate...... an acoustic separation between the control regions. Secondly, the pre- and post-ringing as well as spectral deterioration introduced by the filters should be minimized. The tradeoff between acoustic separation and filter ringing is the focus of this paper. A weighted L2-norm penalty is introduced in the sound...

  14. Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

    International Nuclear Information System (INIS)

    Pedersen, Eja; Berg, Frits van den; Bakker, Roel; Bouma, Jelte

    2010-01-01

    Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road traffic sound could mask wind turbine sound or, in contrast, increases annoyance due to wind turbine noise. Annoyance of road traffic and wind turbine noise was measured in the WINDFARMperception survey in the Netherlands in 2007 (n=725) and related to calculated levels of sound. The presence of road traffic sound did not in general decrease annoyance with wind turbine noise, except when levels of wind turbine sound were moderate (35-40 dB(A) Lden) and road traffic sound level exceeded that level with at least 20 dB(A). Annoyance with both noises was intercorrelated but this correlation was probably due to the influence of individual factors. Furthermore, visibility and attitude towards wind turbines were significantly related to noise annoyance of modern wind turbines. The results can be used for the selection of suitable sites, possibly favouring already noise exposed areas if wind turbine sound levels are sufficiently low.

  15. Structure-borne sound structural vibrations and sound radiation at audio frequencies

    CERN Document Server

    Cremer, L; Petersson, Björn AT

    2005-01-01

    Structure-Borne Sound"" is a thorough introduction to structural vibrations with emphasis on audio frequencies and the associated radiation of sound. The book presents in-depth discussions of fundamental principles and basic problems, in order to enable the reader to understand and solve his own problems. It includes chapters dealing with measurement and generation of vibrations and sound, various types of structural wave motion, structural damping and its effects, impedances and vibration responses of the important types of structures, as well as with attenuation of vibrations, and sound radi

  16. Bending of electromagnetic beams and head-tail radio sources

    International Nuclear Information System (INIS)

    Bodo, G.; Ferrari, A.; Massaglia, S.; Turin Univ.

    1981-01-01

    An interpretation is presented of bridge bending in head-tail radio sources in the framework of an electromagnetic beam model. The physical effect responsible for the structural distortion is proposed to be the refraction of a large-amplitude wave in a medium with a density gradient perpendicular to the wave propagation vector; this gradient is consistently produced by the relative motion of the beam source in the surrounding medium with a velocity higher than the speed of sound. These effects are calculated in some detail and a quantitative fit of model parameters to the typical radio source associated with NGC 1265 is discussed. (author)

  17. Biomimetic Sonar for Electrical Activation of the Auditory Pathway

    Directory of Open Access Journals (Sweden)

    D. Menniti

    2017-01-01

    Full Text Available Relying on the mechanism of bat’s echolocation system, a bioinspired electronic device has been developed to investigate the cortical activity of mammals in response to auditory sensorial stimuli. By means of implanted electrodes, acoustical information about the external environment generated by a biomimetic system and converted in electrical signals was delivered to anatomically selected structures of the auditory pathway. Electrocorticographic recordings showed that cerebral activity response is highly dependent on the information carried out by ultrasounds and is frequency-locked with the signal repetition rate. Frequency analysis reveals that delta and beta rhythm content increases, suggesting that sensorial information is successfully transferred and integrated. In addition, principal component analysis highlights how all the stimuli generate patterns of neural activity which can be clearly classified. The results show that brain response is modulated by echo signal features suggesting that spatial information sent by biomimetic sonar is efficiently interpreted and encoded by the auditory system. Consequently, these results give new perspective in artificial environmental perception, which could be used for developing new techniques useful in treating pathological conditions or influencing our perception of the surroundings.

  18. Side-scan sonar techniques for the characterization of physical properties of artificial benthic habitats

    Directory of Open Access Journals (Sweden)

    Wen-Miin Tian

    2011-01-01

    Full Text Available Side-scan sonar observations conducted at Mito artificial habitat site in the southwest coast off Taiwan, documented the locations of both concrete cubic blocks (more than 10,000 units and scrapped steel boats (39 units deployed previously. Based on their geographic locations, the concrete cubic artificial reefs could be grouped into 14 reef sets. About 30% of the reefs were deployed out of the promulgated site area. For the purpose of artificial habitat site identification and fishery resources management, a database structure was designed to accommodate types and positions of reefs, information of reef sets, bathymetric contours, textures of bottom sediments and geomorphological characteristics. The effectiveness of Mito artificial habitat site was evaluated to be positive after the deployment of both concrete block reefs and steel boat reefs.Observações com sonar de varredura lateral ao largo de Mito na costa sudoeste de Taiwan, revelou a localização de mais de 10.000 blocos de concreto e 39 embarcações de ferro assentados previamente como recifes artificiais. Com base nas imagens obtidas, os cubos de concreto formam 14 grupos separados. Cerca de 30% das unidades de concreto foram assentadas fora das áreas previstas. Para a identificacão correta dos recifes artificiais e manejo adequado dos recursos pesqueiros, foi organizada uma base de dados com informações sobre forma, materiais e posição, e arranjo espacial das unidades recifais, bem como dados de batimetria, natureza do sedimento do fundo e geomorfologia. A eficiência dos recifes artificiais de Mito foi avaliada positivamente após o assentamento tanto das unidades de concreto quanto das embarcações de ferro.

  19. InfoSound

    DEFF Research Database (Denmark)

    Sonnenwald, Diane H.; Gopinath, B.; Haberman, Gary O.

    1990-01-01

    The authors explore ways to enhance users' comprehension of complex applications using music and sound effects to present application-program events that are difficult to detect visually. A prototype system, Infosound, allows developers to create and store musical sequences and sound effects with...

  20. The Sound of Science

    Science.gov (United States)

    Merwade, Venkatesh; Eichinger, David; Harriger, Bradley; Doherty, Erin; Habben, Ryan

    2014-01-01

    While the science of sound can be taught by explaining the concept of sound waves and vibrations, the authors of this article focused their efforts on creating a more engaging way to teach the science of sound--through engineering design. In this article they share the experience of teaching sound to third graders through an engineering challenge…

  1. hab108_0201_east.tif -- Side scan sonar image (East mosaic) from survey effort HMPR-108-2002-01 in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This side scan sonar image of the sea floor (120-350 m water depths) was mosaiced from data collected in 2002.An Edgetech DF1000 side scan system was used for...

  2. Disturbance-specific social responses in long-finned pilot whales, Globicephala melas

    NARCIS (Netherlands)

    Visser, F.; Curé, C.; Kvadsheim, P.H.; Lam, F.P.A.; Tyack, P.L.; Miller, P.J.O.

    2016-01-01

    Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: Tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of

  3. Undergraduates Conducting Research Using High-Resolution Multibeam and Sidescan Sonar to Map and Characterize the Seabed: the BEAMS Program

    Science.gov (United States)

    Harris, M. S.; Sautter, L.

    2017-12-01

    The College of Charleston's BEnthic Acoustic Mapping and Survey (BEAMS) Program has just completed its 10th year of operation, and has proven to be remarkably effective at activating and maintaining undergraduate student interest in conducting research using sophisticated software, state-of-the-art instrumentation, enormous datasets, and significant experiential time. BEAMS students conduct research as part of a minimum 3-course sequence of marine geology-based content, marine geospatial software, and seafloor research courses. Over 140 students have completed the program, 56% of the graduated students remain active in the marine geospatial workforce or academic arenas. Forty-eight percent (48%) of those students are female. As undergraduates, students not only conduct independent research projects, but present their work at national conferences each year. Additionally, over 90 % of all "BEAMers" have been provided a 2-3 day at-sea experience on a dedicated BEAMS Program multibeam survey research cruise, and many students also volunteer as survey technicians aboard NOAA research vessels. Critical partnerships have developed with private industry to provide numerous collaborative opportunities and an employment/employer pipeline, as well as provision of software and hardware at many fiscal levels. Ongoing collaboration with the Marine Institute of Ireland and the National and Kapodistrian University of Athens has also provided valuable field opportunities and collaborative experiences. This talk will summarize the program while highlighting some of the key areas and topics investigated by students, including detailed geomorphologic studies of continental margins, submarine canyons, tectonic features and seamounts. Students also work with NOAA investigators to aid in the characterization of fish and deep coral habitats, and with BOEM researchers to study offshore windfield suitability and submerged cultural landscapes. Our sister program at the University of

  4. Echo 7: Magnetospheric properties determined by artificial electron beams

    International Nuclear Information System (INIS)

    Nemzek, R.J.

    1990-01-01

    The sounding rocket Echo 7 was launched from the Poker Flat Research Range. An on-board accelerator injected high-power electron beams into the magnetospheric tail near L = 6.5. After mirroring at the southern conjugate point, about 20 percent of the initial beam electrons returned to the North as Conjugate Echoes, where detectors (scintillators and spectrometers) on four subpayloads measured their energy and bounce time. The other 80 percent of the beam was pitch angle diffused by wave near the equatorial plane either into the conjugate atmosphere or up to mirror points above the payload. Comparison of measured values to calculations showed that the actual magnetosphere during the flight was well-described by the Tsyganenko-Usmanov model magnetosphere with a Kp value of 2- or 2+. Analysis of echo energies yielded values for the highly variable magnetospheric convection electric field

  5. The Textile Form of Sound

    DEFF Research Database (Denmark)

    Bendixen, Cecilie

    Sound is a part of architecture, and sound is complex. Upon this, sound is invisible. How is it then possible to design visual objects that interact with the sound? This paper addresses the problem of how to get access to the complexity of sound and how to make textile material revealing the form...... goemetry by analysing the sound pattern at a specific spot. This analysis is done theoretically with algorithmic systems and practical with waves in water. The paper describes the experiments and the findings, and explains how an analysis of sound can be catched in a textile form....

  6. Higher-Order Statistics for the Detection of Small Objects in a Noisy Background Application on Sonar Imaging

    Directory of Open Access Journals (Sweden)

    M. Amate

    2007-01-01

    Full Text Available An original algorithm for the detection of small objects in a noisy background is proposed. Its application to underwater objects detection by sonar imaging is addressed. This new method is based on the use of higher-order statistics (HOS that are locally estimated on the images. The proposed algorithm is divided into two steps. In a first step, HOS (skewness and kurtosis are estimated locally using a square sliding computation window. Small deterministic objects have different statistical properties from the background they are thus highlighted. The influence of the signal-to-noise ratio (SNR on the results is studied in the case of Gaussian noise. Mathematical expressions of the estimators and of the expected performances are derived and are experimentally confirmed. In a second step, the results are focused by a matched filter using a theoretical model. This enables the precise localization of the regions of interest. The proposed method generalizes to other statistical distributions and we derive the theoretical expressions of the HOS estimators in the case of a Weibull distribution (both when only noise is present or when a small deterministic object is present within the filtering window. This enables the application of the proposed technique to the processing of synthetic aperture sonar data containing underwater mines whose echoes have to be detected and located. Results on real data sets are presented and quantitatively evaluated using receiver operating characteristic (ROC curves.

  7. Reduction of heart sound interference from lung sound signals using empirical mode decomposition technique.

    Science.gov (United States)

    Mondal, Ashok; Bhattacharya, P S; Saha, Goutam

    2011-01-01

    During the recording time of lung sound (LS) signals from the chest wall of a subject, there is always heart sound (HS) signal interfering with it. This obscures the features of lung sound signals and creates confusion on pathological states, if any, of the lungs. A novel method based on empirical mode decomposition (EMD) technique is proposed in this paper for reducing the undesired heart sound interference from the desired lung sound signals. In this, the mixed signal is split into several components. Some of these components contain larger proportions of interfering signals like heart sound, environmental noise etc. and are filtered out. Experiments have been conducted on simulated and real-time recorded mixed signals of heart sound and lung sound. The proposed method is found to be superior in terms of time domain, frequency domain, and time-frequency domain representations and also in listening test performed by pulmonologist.

  8. Model-based seafloor characterization employing multi-beam angular backscatter data - A comparative study with dual-frequency single beam

    Digital Repository Service at National Institute of Oceanography (India)

    Haris, K.; Chakraborty, B.; De, C.; Desai, R.G.P.; Fernandes, W.A.

    developed by Jackson et al., 3 has been extensively applied to this approach. 4-6 In this work, characterization of seafloor sediments is achieved by employing a MB system (Simrad EM 1002) operable at 95 kHz. Here, the seafloor parameters are estimated... pre-formed beams data were acquired during two cruises using the EM1002 echo-sounding system installed onboard CRV Sagar Sukti (cruises: SASU-108 and 134). 13,14 Besides calculating the angular backscatter strengths using the MB system, the modeled...

  9. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2008-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  10. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2010-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  11. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2007-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  12. Non-contact test of coating by means of laser-induced ultrasonic excitation and holographic sound representation

    International Nuclear Information System (INIS)

    Crostack, H.A.; Pohl, K.Y.; Radtke, U.

    1991-01-01

    In order to circumvent the problems of introducing and picking off sound, which occur in conventional ultrasonic testing, a completely non-contact test process was developed. The ultrasonic surface wave required for the test is generated without contact by absorption of laser beams. The recording of the ultrasound also occurs by a non-contact holographic interferometry technique, which permits a large scale representation of the sound. Using the example of MCrAlY and ZrO 2 layers, the suitability of the process for testing thermally sprayed coatings on metal substrates is identified. The possibilities and limits of the process for the detection and description of delamination and cracks are shown. (orig.) [de

  13. NASA Space Sounds API

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has released a series of space sounds via sound cloud. We have abstracted away some of the hassle in accessing these sounds, so that developers can play with...

  14. 77 FR 27720 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2012-05-11

    ...-injurious) thresholds for underwater sound sources (except explosives and tactical active sonar) based on... this recommendation as a mitigation measure to be impracticable for both economic and practical reasons... vessel activity, Apache will follow NMFS' Marine Mammal Viewing Guidelines and Regulations and will alter...

  15. Sound Insulation between Dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit

    2011-01-01

    Regulatory sound insulation requirements for dwellings exist in more than 30 countries in Europe. In some countries, requirements have existed since the 1950s. Findings from comparative studies show that sound insulation descriptors and requirements represent a high degree of diversity...... and initiate – where needed – improvement of sound insulation of new and existing dwellings in Europe to the benefit of the inhabitants and the society. A European COST Action TU0901 "Integrating and Harmonizing Sound Insulation Aspects in Sustainable Urban Housing Constructions", has been established and runs...... 2009-2013. The main objectives of TU0901 are to prepare proposals for harmonized sound insulation descriptors and for a European sound classification scheme with a number of quality classes for dwellings. Findings from the studies provide input for the discussions in COST TU0901. Data collected from 24...

  16. Remembering that big things sound big: Sound symbolism and associative memory.

    Science.gov (United States)

    Preziosi, Melissa A; Coane, Jennifer H

    2017-01-01

    According to sound symbolism theory, individual sounds or clusters of sounds can convey meaning. To examine the role of sound symbolic effects on processing and memory for nonwords, we developed a novel set of 100 nonwords to convey largeness (nonwords containing plosive consonants and back vowels) and smallness (nonwords containing fricative consonants and front vowels). In Experiments 1A and 1B, participants rated the size of the 100 nonwords and provided definitions to them as if they were products. Nonwords composed of fricative/front vowels were rated as smaller than those composed of plosive/back vowels. In Experiment 2, participants studied sound symbolic congruent and incongruent nonword and participant-generated definition pairings. Definitions paired with nonwords that matched the size and participant-generated meanings were recalled better than those that did not match. When the participant-generated definitions were re-paired with other nonwords, this mnemonic advantage was reduced, although still reliable. In a final free association study, the possibility that plosive/back vowel and fricative/front vowel nonwords elicit sound symbolic size effects due to mediation from word neighbors was ruled out. Together, these results suggest that definitions that are sound symbolically congruent with a nonword are more memorable than incongruent definition-nonword pairings. This work has implications for the creation of brand names and how to create brand names that not only convey desired product characteristics, but also are memorable for consumers.

  17. An Antropologist of Sound

    DEFF Research Database (Denmark)

    Groth, Sanne Krogh

    2015-01-01

    PROFESSOR PORTRAIT: Sanne Krogh Groth met Holger Schulze, newly appointed professor in Musicology at the Department for Arts and Cultural Studies, University of Copenhagen, to a talk about anthropology of sound, sound studies, musical canons and ideology.......PROFESSOR PORTRAIT: Sanne Krogh Groth met Holger Schulze, newly appointed professor in Musicology at the Department for Arts and Cultural Studies, University of Copenhagen, to a talk about anthropology of sound, sound studies, musical canons and ideology....

  18. The effect of nonlinear propagation on heating of tissue: A numerical model of diagnostic ultrasound beams

    Science.gov (United States)

    Cahill, Mark D.; Humphrey, Victor F.; Doody, Claire

    2000-07-01

    Thermal safety indices for diagnostic ultrasound beams are calculated under the assumption that the sound propagates under linear conditions. A non-axisymmetric finite difference model is used to solve the KZK equation, and so to model the beam of a diagnostic scanner in pulsed Doppler mode. Beams from both a uniform focused rectangular source and a linear array are considered. Calculations are performed in water, and in attenuating media with tissue-like characteristics. Attenuating media are found to exhibit significant nonlinear effects for finite-amplitude beams. The resulting loss of intensity by the beam is then used as the source term in a model of tissue heating to estimate the maximum temperature rises. These are compared with the thermal indices, derived from the properties of the water-propagated beams.

  19. Effect of electron beam on quality and physiological metabolism of blueberry

    International Nuclear Information System (INIS)

    Zhou Huijuan; Ye Zhengwen; Zhang Xueying; Su Mingshen; Du Jihong; Zhang Minqian

    2013-01-01

    In order to explore safe, simple and effective storage technology, experiment was conducted with 'ai li ao te' blueberry for studying the effect of electron beam on quality and physiological metabolism. Fruit was stored at temperature of (1 ± 0.5)℃, with RH of 80% ∼ 85%, and treated with electron beam of 0.5, 1, 1.5, 2, 3 kGy. The results showed that the proper dose of electron beam could decline the bad fruit rate and weightlessness, restrain respiration intensity, alleviate the decline of soluble solids, acid and Vc content. Meanwhile it did not have significant negative effects on pulp colour. All these showed that electron beam of 1 kGy treatment could keep the best storage quality of blueberry, keep the sound berry and weightlessness rate at > 90% and < 10% respectively, prolong the effective storage time from 30d to 60d. (authors)

  20. Summary of Session 4 "Beam Energy"

    CERN Document Server

    Siemko, A

    2011-01-01

    In this session, the possible scenarios for the beam energy in the LHC 2011 run were discussed. The benefits for the physics reach for physics operations at s larger than 7 TeV were reviewed. The main goal was, however, to establish the necessary information for a sound risk analysis by assessing the probability of thermal runaway and evaluating the consequences of a hypothetical incident. A new technique to improve the knowledge of joint resistances of the cooper busbars and therefore the reliability of the risk analysis has also been discussed.

  1. Long Island Sound Environmental Studies; 01 October 1991 to 31 August 1998 (NODC Accession 9900223)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Abstract: This CD-ROM (Compact Disk - Read Only Memory) contains sidescan sonar, high-resolution seismic-reflection, bathymetric, textural, and bibliographic data...

  2. Sound specificity effects in spoken word recognition: The effect of integrality between words and sounds

    DEFF Research Database (Denmark)

    Strori, Dorina; Zaar, Johannes; Cooke, Martin

    2017-01-01

    Recent evidence has shown that nonlinguistic sounds co-occurring with spoken words may be retained in memory and affect later retrieval of the words. This sound-specificity effect shares many characteristics with the classic voice-specificity effect. In this study, we argue that the sound......-specificity effect is conditional upon the context in which the word and sound coexist. Specifically, we argue that, besides co-occurrence, integrality between words and sounds is a crucial factor in the emergence of the effect. In two recognition-memory experiments, we compared the emergence of voice and sound...... from a mere co-occurrence context effect by removing the intensity modulation. The absence of integrality led to the disappearance of the sound-specificity effect. Taken together, the results suggest that the assimilation of background sounds into memory cannot be reduced to a simple context effect...

  3. Active sound reduction system and method

    NARCIS (Netherlands)

    2016-01-01

    The present invention refers to an active sound reduction system and method for attenuation of sound emitted by a primary sound source, especially for attenuation of snoring sounds emitted by a human being. This system comprises a primary sound source, at least one speaker as a secondary sound

  4. Sound Symbolism in Basic Vocabulary

    Directory of Open Access Journals (Sweden)

    Søren Wichmann

    2010-04-01

    Full Text Available The relationship between meanings of words and their sound shapes is to a large extent arbitrary, but it is well known that languages exhibit sound symbolism effects violating arbitrariness. Evidence for sound symbolism is typically anecdotal, however. Here we present a systematic approach. Using a selection of basic vocabulary in nearly one half of the world’s languages we find commonalities among sound shapes for words referring to same concepts. These are interpreted as due to sound symbolism. Studying the effects of sound symbolism cross-linguistically is of key importance for the understanding of language evolution.

  5. Disturbance-specific social responses in long-finned pilot whales, Globicephala melas

    Science.gov (United States)

    Visser, Fleur; Curé, Charlotte; Kvadsheim, Petter H.; Lam, Frans-Peter A.; Tyack, Peter L.; Miller, Patrick J. O.

    2016-06-01

    Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of tagged individuals were recorded along with the social behaviour of their groups. All three disturbance types resulted in larger group sizes, increasing social cohesion during disturbance. However, the nature and magnitude of other responses differed between disturbance types. Tagging effort resulted in a clear increase in synchrony and a tendency to reduce surface logging and to become silent (21% of cases), whereas pilot whales increased surface resting during sonar exposure. Killer whale sounds elicited increased calling rates and the aggregation of multiple groups, which approached the sound source together. This behaviour appears to represent a mobbing response, a likely adaptive social defence against predators or competitors. All observed response-tactics would reduce risk of loss of group coordination, suggesting that, in social pilot whales, this could drive behavioural responses to disturbance. However, the behavioural means used to achieve social coordination depends upon other considerations, which are disturbance-specific.

  6. Sounding the Alarm: An Introduction to Ecological Sound Art

    Directory of Open Access Journals (Sweden)

    Jonathan Gilmurray

    2016-12-01

    Full Text Available In recent years, a number of sound artists have begun engaging with ecological issues through their work, forming a growing movement of ˝ecological sound art˝. This paper traces its development, examines its influences, and provides examples of the artists whose work is currently defining this important and timely new field.

  7. Experiences from using Autonomous Underwater Vehicles and Synthetic Aperture Sonar for Sediment and Habitat Mapping

    Science.gov (United States)

    Thorsnes, T.; Bjarnadóttir, L. R.

    2017-12-01

    Emerging platforms and tools like autonomous underwater vehicles and synthetic aperture sonars provide interesting opportunities for making seabed mapping more efficient and precise. Sediment grain-size maps are an important product in their own right and a key input for habitat and biotope maps. National and regional mapping programmes are tasked with mapping large areas, and survey efficiency, data quality, and resulting map confidence are important considerations when selecting the mapping strategy. Since 2005, c. 175,000 square kilometres of the Norwegian continental shelf and continental slope has been mapped with respect to sediments, habitats and biodiversity, and pollution under the MAREANO programme (www.mareano.no). At present the sediment mapping is based on a combination of ship-borne multibeam bathymetry and backscatter, visual documentation using a towed video platform, and grab sampling. We have now tested a new approach, using an Autonomous Underwater Vehicle (AUV) as the survey platform for the collection of acoustic data (Synthetic Aperture Sonar (SAS), EM2040 bathymetry and backscatter) and visual data (still images using a TFish colour photo system). This pilot project was conducted together the Norwegian Hydrographic Service, the Institute of Marine Research (biology observations) and the Norwegian Defence Research Establishment (operation of ship and AUV). The test site reported here is the Vesterdjupet area, offshore Lofoten, northern Norway. The water depth is between 170 and 300 metres, with sediments ranging from gravel, cobbles and boulders to sandy mud. A cold-water coral reef, associated with bioclastic sediments was also present in the study area. The presentation will give an overview of the main findings and experiences gained from this pilot project with a focus on geological mapping and will also discuss the relevance of AUV-based mapping to large-area mapping programmes like MAREANO.

  8. Sound Stuff? Naïve materialism in middle-school students' conceptions of sound

    Science.gov (United States)

    Eshach, Haim; Schwartz, Judah L.

    2006-06-01

    Few studies have dealt with students’ preconceptions of sounds. The current research employs Reiner et al. (2000) substance schema to reveal new insights about students’ difficulties in understanding this fundamental topic. It aims not only to detect whether the substance schema is present in middle school students’ thinking, but also examines how students use the schema’s properties. It asks, moreover, whether the substance schema properties are used as islands of local consistency or whether one can identify more global coherent consistencies among the properties that the students use to explain the sound phenomena. In-depth standardized open-ended interviews were conducted with ten middle school students. Consistent with the substance schema, sound was perceived by our participants as being pushable, frictional, containable, or transitional. However, sound was also viewed as a substance different from the ordinary with respect to its stability, corpuscular nature, additive properties, and inertial characteristics. In other words, students’ conceptions of sound do not seem to fit Reiner et al.’s schema in all respects. Our results also indicate that students’ conceptualization of sound lack internal consistency. Analyzing our results with respect to local and global coherence, we found students’ conception of sound is close to diSessa’s “loosely connected, fragmented collection of ideas.” The notion that sound is perceived only as a “sort of a material,” we believe, requires some revision of the substance schema as it applies to sound. The article closes with a discussion concerning the implications of the results for instruction.

  9. Sound symbolism: the role of word sound in meaning.

    Science.gov (United States)

    Svantesson, Jan-Olof

    2017-09-01

    The question whether there is a natural connection between sound and meaning or if they are related only by convention has been debated since antiquity. In linguistics, it is usually taken for granted that 'the linguistic sign is arbitrary,' and exceptions like onomatopoeia have been regarded as marginal phenomena. However, it is becoming more and more clear that motivated relations between sound and meaning are more common and important than has been thought. There is now a large and rapidly growing literature on subjects as ideophones (or expressives), words that describe how a speaker perceives a situation with the senses, and phonaesthemes, units like English gl-, which occur in many words that share a meaning component (in this case 'light': gleam, glitter, etc.). Furthermore, psychological experiments have shown that sound symbolism in one language can be understood by speakers of other languages, suggesting that some kinds of sound symbolism are universal. WIREs Cogn Sci 2017, 8:e1441. doi: 10.1002/wcs.1441 For further resources related to this article, please visit the WIREs website. © 2017 Wiley Periodicals, Inc.

  10. Sound-by-sound thalamic stimulation modulates midbrain auditory excitability and relative binaural sensitivity in frogs.

    Science.gov (United States)

    Ponnath, Abhilash; Farris, Hamilton E

    2014-01-01

    Descending circuitry can modulate auditory processing, biasing sensitivity to particular stimulus parameters and locations. Using awake in vivo single unit recordings, this study tested whether electrical stimulation of the thalamus modulates auditory excitability and relative binaural sensitivity in neurons of the amphibian midbrain. In addition, by using electrical stimuli that were either longer than the acoustic stimuli (i.e., seconds) or presented on a sound-by-sound basis (ms), experiments addressed whether the form of modulation depended on the temporal structure of the electrical stimulus. Following long duration electrical stimulation (3-10 s of 20 Hz square pulses), excitability (spikes/acoustic stimulus) to free-field noise stimuli decreased by 32%, but returned over 600 s. In contrast, sound-by-sound electrical stimulation using a single 2 ms duration electrical pulse 25 ms before each noise stimulus caused faster and varied forms of modulation: modulation lasted sound-by-sound electrical stimulation varied between different acoustic stimuli, including for different male calls, suggesting modulation is specific to certain stimulus attributes. For binaural units, modulation depended on the ear of input, as sound-by-sound electrical stimulation preceding dichotic acoustic stimulation caused asymmetric modulatory effects: sensitivity shifted for sounds at only one ear, or by different relative amounts for both ears. This caused a change in the relative difference in binaural sensitivity. Thus, sound-by-sound electrical stimulation revealed fast and ear-specific (i.e., lateralized) auditory modulation that is potentially suited to shifts in auditory attention during sound segregation in the auditory scene.

  11. Sound specificity effects in spoken word recognition: The effect of integrality between words and sounds.

    Science.gov (United States)

    Strori, Dorina; Zaar, Johannes; Cooke, Martin; Mattys, Sven L

    2018-01-01

    Recent evidence has shown that nonlinguistic sounds co-occurring with spoken words may be retained in memory and affect later retrieval of the words. This sound-specificity effect shares many characteristics with the classic voice-specificity effect. In this study, we argue that the sound-specificity effect is conditional upon the context in which the word and sound coexist. Specifically, we argue that, besides co-occurrence, integrality between words and sounds is a crucial factor in the emergence of the effect. In two recognition-memory experiments, we compared the emergence of voice and sound specificity effects. In Experiment 1 , we examined two conditions where integrality is high. Namely, the classic voice-specificity effect (Exp. 1a) was compared with a condition in which the intensity envelope of a background sound was modulated along the intensity envelope of the accompanying spoken word (Exp. 1b). Results revealed a robust voice-specificity effect and, critically, a comparable sound-specificity effect: A change in the paired sound from exposure to test led to a decrease in word-recognition performance. In the second experiment, we sought to disentangle the contribution of integrality from a mere co-occurrence context effect by removing the intensity modulation. The absence of integrality led to the disappearance of the sound-specificity effect. Taken together, the results suggest that the assimilation of background sounds into memory cannot be reduced to a simple context effect. Rather, it is conditioned by the extent to which words and sounds are perceived as integral as opposed to distinct auditory objects.

  12. Analysis, Synthesis, and Perception of Musical Sounds The Sound of Music

    CERN Document Server

    Beauchamp, James W

    2007-01-01

    Analysis, Synthesis, and Perception of Musical Sounds contains a detailed treatment of basic methods for analysis and synthesis of musical sounds, including the phase vocoder method, the McAulay-Quatieri frequency-tracking method, the constant-Q transform, and methods for pitch tracking with several examples shown. Various aspects of musical sound spectra such as spectral envelope, spectral centroid, spectral flux, and spectral irregularity are defined and discussed. One chapter is devoted to the control and synthesis of spectral envelopes. Two advanced methods of analysis/synthesis are given: "Sines Plus Transients Plus Noise" and "Spectrotemporal Reassignment" are covered. Methods for timbre morphing are given. The last two chapters discuss the perception of musical sounds based on discrimination and multidimensional scaling timbre models.

  13. Michael Jackson's Sound Stages

    OpenAIRE

    Morten Michelsen

    2012-01-01

    In order to discuss analytically spatial aspects of recorded sound William Moylan’s concept of ‘sound stage’ is developed within a musicological framework as part of a sound paradigm which includes timbre, texture and sound stage. Two Michael Jackson songs (‘The Lady in My Life’ from 1982 and ‘Scream’ from 1995) are used to: a) demonstrate the value of such a conceptualisation, and b) demonstrate that the model has its limits, as record producers in the 1990s began ignoring the conventions of...

  14. ABOUT SOUNDS IN VIDEO GAMES

    Directory of Open Access Journals (Sweden)

    Denikin Anton A.

    2012-12-01

    Full Text Available The article considers the aesthetical and practical possibilities for sounds (sound design in video games and interactive applications. Outlines the key features of the game sound, such as simulation, representativeness, interactivity, immersion, randomization, and audio-visuality. The author defines the basic terminology in study of game audio, as well as identifies significant aesthetic differences between film sounds and sounds in video game projects. It is an attempt to determine the techniques of art analysis for the approaches in study of video games including aesthetics of their sounds. The article offers a range of research methods, considering the video game scoring as a contemporary creative practice.

  15. Sound [signal] noise

    DEFF Research Database (Denmark)

    Bjørnsten, Thomas

    2012-01-01

    The article discusses the intricate relationship between sound and signification through notions of noise. The emergence of new fields of sonic artistic practices has generated several questions of how to approach sound as aesthetic form and material. During the past decade an increased attention...... has been paid to, for instance, a category such as ‘sound art’ together with an equally strengthened interest in phenomena and concepts that fall outside the accepted aesthetic procedures and constructions of what we traditionally would term as musical sound – a recurring example being ‘noise’....

  16. Beneath sci-fi sound: primer, science fiction sound design, and American independent cinema

    OpenAIRE

    Johnston, Nessa

    2012-01-01

    Primer is a very low budget science-fiction film that deals with the subject of time travel; however, it looks and sounds quite distinctively different from other films associated with the genre. While Hollywood blockbuster sci-fi relies on “sound spectacle” as a key attraction, in contrast Primer sounds “lo-fi” and screen-centred, mixed to two channel stereo rather than the now industry-standard 5.1 surround sound. Although this is partly a consequence of the economics of its production, the...

  17. mos115_0403.TIF -- Multibeam backscatter sonar image for the nearshore Cape Flattery area: Data from survey effort HMPR-115-2004-03 in the Olympic Coast national marine sanctuary.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This multibeam backscatter sonar image of the sea floor (0-200 m water depths) was mosaiced from data collected fromvarious mapping efforts each October from...

  18. Probing the magnetsophere with artificial electron beams

    International Nuclear Information System (INIS)

    Winckler, J.R.

    1981-01-01

    An analysis is conducted of the University of Minnesota Electron Echo experiments, which so far have included five sounding rocket experiments. The concept of the Echo experiment is to inject electron beam pulses from a rocket into the ionosphere at altitudes in the range from 100 to 300 km. The electrons move to the conjugate hemisphere following magnetic field lines and return on neighboring field lines to the neighborhood of the rocket where the pulses may be detected and analyzed. Attention is given to the detection and analysis of echoes, the structure of echoes, and the Echo V experiment. The Echo V experiment showed clearly that detection of remote echo beams by atmospheric fluorescence using low light level TV system is not a viable technique. A future experiment is to use throw-away detectors for direct remote echo detection

  19. Sound classification of dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit

    2012-01-01

    National schemes for sound classification of dwellings exist in more than ten countries in Europe, typically published as national standards. The schemes define quality classes reflecting different levels of acoustical comfort. Main criteria concern airborne and impact sound insulation between...... dwellings, facade sound insulation and installation noise. The schemes have been developed, implemented and revised gradually since the early 1990s. However, due to lack of coordination between countries, there are significant discrepancies, and new standards and revisions continue to increase the diversity...... is needed, and a European COST Action TU0901 "Integrating and Harmonizing Sound Insulation Aspects in Sustainable Urban Housing Constructions", has been established and runs 2009-2013, one of the main objectives being to prepare a proposal for a European sound classification scheme with a number of quality...

  20. Vocal Imitations of Non-Vocal Sounds

    Science.gov (United States)

    Houix, Olivier; Voisin, Frédéric; Misdariis, Nicolas; Susini, Patrick

    2016-01-01

    Imitative behaviors are widespread in humans, in particular whenever two persons communicate and interact. Several tokens of spoken languages (onomatopoeias, ideophones, and phonesthemes) also display different degrees of iconicity between the sound of a word and what it refers to. Thus, it probably comes at no surprise that human speakers use a lot of imitative vocalizations and gestures when they communicate about sounds, as sounds are notably difficult to describe. What is more surprising is that vocal imitations of non-vocal everyday sounds (e.g. the sound of a car passing by) are in practice very effective: listeners identify sounds better with vocal imitations than with verbal descriptions, despite the fact that vocal imitations are inaccurate reproductions of a sound created by a particular mechanical system (e.g. a car driving by) through a different system (the voice apparatus). The present study investigated the semantic representations evoked by vocal imitations of sounds by experimentally quantifying how well listeners could match sounds to category labels. The experiment used three different types of sounds: recordings of easily identifiable sounds (sounds of human actions and manufactured products), human vocal imitations, and computational “auditory sketches” (created by algorithmic computations). The results show that performance with the best vocal imitations was similar to the best auditory sketches for most categories of sounds, and even to the referent sounds themselves in some cases. More detailed analyses showed that the acoustic distance between a vocal imitation and a referent sound is not sufficient to account for such performance. Analyses suggested that instead of trying to reproduce the referent sound as accurately as vocally possible, vocal imitations focus on a few important features, which depend on each particular sound category. These results offer perspectives for understanding how human listeners store and access long

  1. Sound Art Situations

    DEFF Research Database (Denmark)

    Krogh Groth, Sanne; Samson, Kristine

    2017-01-01

    and combine theories from several fields. Aspects of sound art studies, performance studies and contemporary art studies are presented in order to theoretically explore the very diverse dimensions of the two sound art pieces: Visual, auditory, performative, social, spatial and durational dimensions become......This article is an analysis of two sound art performances that took place June 2015 in outdoor public spaces in the social housing area Urbanplanen in Copenhagen, Denmark. The two performances were On the production of a poor acoustics by Brandon LaBelle and Green Interactive Biofeedback...... Environments (GIBE) by Jeremy Woodruff. In order to investigate the complex situation that arises when sound art is staged in such contexts, the authors of this article suggest exploring the events through approaching them as ‘situations’ (Doherty 2009). With this approach it becomes possible to engage...

  2. Characteristic sounds facilitate visual search.

    Science.gov (United States)

    Iordanescu, Lucica; Guzman-Martinez, Emmanuel; Grabowecky, Marcia; Suzuki, Satoru

    2008-06-01

    In a natural environment, objects that we look for often make characteristic sounds. A hiding cat may meow, or the keys in the cluttered drawer may jingle when moved. Using a visual search paradigm, we demonstrated that characteristic sounds facilitated visual localization of objects, even when the sounds carried no location information. For example, finding a cat was faster when participants heard a meow sound. In contrast, sounds had no effect when participants searched for names rather than pictures of objects. For example, hearing "meow" did not facilitate localization of the word cat. These results suggest that characteristic sounds cross-modally enhance visual (rather than conceptual) processing of the corresponding objects. Our behavioral demonstration of object-based cross-modal enhancement complements the extensive literature on space-based cross-modal interactions. When looking for your keys next time, you might want to play jingling sounds.

  3. Determining the speed of sound in the air by sound wave interference

    Science.gov (United States)

    Silva, Abel A.

    2017-07-01

    Mechanical waves propagate through material media. Sound is an example of a mechanical wave. In fluids like air, sound waves propagate through successive longitudinal perturbations of compression and decompression. Audible sound frequencies for human ears range from 20 to 20 000 Hz. In this study, the speed of sound v in the air is determined using the identification of maxima of interference from two synchronous waves at frequency f. The values of v were correct to 0 °C. The experimental average value of {\\bar{ν }}\\exp =336 +/- 4 {{m}} {{{s}}}-1 was found. It is 1.5% larger than the reference value. The standard deviation of 4 m s-1 (1.2% of {\\bar{ν }}\\exp ) is an improved value by the use of the concept of the central limit theorem. The proposed procedure to determine the speed of sound in the air aims to be an academic activity for physics classes of scientific and technological courses in college.

  4. Fluid Sounds

    DEFF Research Database (Denmark)

    Explorations and analysis of soundscapes have, since Canadian R. Murray Schafer's work during the early 1970's, developed into various established research - and artistic disciplines. The interest in sonic environments is today present within a broad range of contemporary art projects and in arch......Explorations and analysis of soundscapes have, since Canadian R. Murray Schafer's work during the early 1970's, developed into various established research - and artistic disciplines. The interest in sonic environments is today present within a broad range of contemporary art projects...... and in architectural design. Aesthetics, psychoacoustics, perception, and cognition are all present in this expanding field embracing such categories as soundscape composition, sound art, sonic art, sound design, sound studies and auditory culture. Of greatest significance to the overall field is the investigation...

  5. The influence of environmental sound training on the perception of spectrally degraded speech and environmental sounds.

    Science.gov (United States)

    Shafiro, Valeriy; Sheft, Stanley; Gygi, Brian; Ho, Kim Thien N

    2012-06-01

    Perceptual training with spectrally degraded environmental sounds results in improved environmental sound identification, with benefits shown to extend to untrained speech perception as well. The present study extended those findings to examine longer-term training effects as well as effects of mere repeated exposure to sounds over time. Participants received two pretests (1 week apart) prior to a week-long environmental sound training regimen, which was followed by two posttest sessions, separated by another week without training. Spectrally degraded stimuli, processed with a four-channel vocoder, consisted of a 160-item environmental sound test, word and sentence tests, and a battery of basic auditory abilities and cognitive tests. Results indicated significant improvements in all speech and environmental sound scores between the initial pretest and the last posttest with performance increments following both exposure and training. For environmental sounds (the stimulus class that was trained), the magnitude of positive change that accompanied training was much greater than that due to exposure alone, with improvement for untrained sounds roughly comparable to the speech benefit from exposure. Additional tests of auditory and cognitive abilities showed that speech and environmental sound performance were differentially correlated with tests of spectral and temporal-fine-structure processing, whereas working memory and executive function were correlated with speech, but not environmental sound perception. These findings indicate generalizability of environmental sound training and provide a basis for implementing environmental sound training programs for cochlear implant (CI) patients.

  6. Sound Surfing Network (SSN): Mobile Phone-based Sound Spatialization with Audience Collaboration

    OpenAIRE

    Park, Saebyul; Ban, Seonghoon; Hong, Dae Ryong; Yeo, Woon Seung

    2013-01-01

    SSN (Sound Surfing Network) is a performance system that provides a new musicalexperience by incorporating mobile phone-based spatial sound control tocollaborative music performance. SSN enables both the performer and theaudience to manipulate the spatial distribution of sound using the smartphonesof the audience as distributed speaker system. Proposing a new perspective tothe social aspect music appreciation, SSN will provide a new possibility tomobile music performances in the context of in...

  7. The Influence of Changing Sea Conditions on Shipping Noise, Including Effects of Wind, Fish and Climate Change

    NARCIS (Netherlands)

    Ainslie, M.A.; Jong, C.A.F. de

    2011-01-01

    Early human interest in ambient noise in the sea, especially during and after the Second World War, resulted from its effect on limiting the performance of military search sonar [Urick 1983]. While that interest continues, it is now accompanied by non-military uses of underwater sound, such as

  8. Enhancing Tele-robotics with Immersive Virtual Reality

    Science.gov (United States)

    2017-11-03

    The spheres displayed in the virtual environment represent the real-world readings from the robot in real-time from its LRF and sonar sensors. In...Inc., is comprised of an advanced graphics rendering engine, sound engine, and physics and animation engines. This game engine is capable of delivering

  9. Sound Exposure of Symphony Orchestra Musicians

    DEFF Research Database (Denmark)

    Schmidt, Jesper Hvass; Pedersen, Ellen Raben; Juhl, Peter Møller

    2011-01-01

    dBA and their left ear was exposed 4.6 dB more than the right ear. Percussionists were exposed to high sound peaks >115 dBC but less continuous sound exposure was observed in this group. Musicians were exposed up to LAeq8h of 92 dB and a majority of musicians were exposed to sound levels exceeding......Background: Assessment of sound exposure by noise dosimetry can be challenging especially when measuring the exposure of classical orchestra musicians where sound originate from many different instruments. A new measurement method of bilateral sound exposure of classical musicians was developed...... and used to characterize sound exposure of the left and right ear simultaneously in two different symphony orchestras.Objectives: To measure binaural sound exposure of professional classical musicians and to identify possible exposure risk factors of specific musicians.Methods: Sound exposure was measured...

  10. ELF waves and ion resonances produced by an electron beam emitting rocket in the ionosphere

    International Nuclear Information System (INIS)

    Winckler, J.R.; Abe, Y.; Erickson, K.N.

    1986-01-01

    Results are reported from the ECHO-6 electron-beam-injection experiment, performed in the auroral-zone ionosphere on March 30, 1983 using a sounding rocket equipped with two electron guns and a free-flying plasma-diagnostics instrument package. The data are presented in extensive graphs and diagrams and characterized in detail. Large ELF wave variations, superposed on the strong beam-sector-directed quasi-dc component, are observed in the 100-eV beam-induced plasma when the beam is injected in a transverse spiral, but not when it is injected upward parallel to the magnetic-field line. ELF activity is found to be suppressed whenever the rocket passed through field lines with auroral activity, suggesting that the waves are produced by the interaction of the beam potentials, plasma currents, and return currents neutralizing the accelerator payload. 12 references

  11. Letter-Sound Reading: Teaching Preschool Children Print-to-Sound Processing

    Science.gov (United States)

    Wolf, Gail Marie

    2016-01-01

    This intervention study investigated the growth of letter sound reading and growth of consonant-vowel-consonant (CVC) word decoding abilities for a representative sample of 41 US children in preschool settings. Specifically, the study evaluated the effectiveness of a 3-step letter-sound teaching intervention in teaching preschool children to…

  12. Modelling Hyperboloid Sound Scattering

    DEFF Research Database (Denmark)

    Burry, Jane; Davis, Daniel; Peters, Brady

    2011-01-01

    The Responsive Acoustic Surfaces workshop project described here sought new understandings about the interaction between geometry and sound in the arena of sound scattering. This paper reports on the challenges associated with modelling, simulating, fabricating and measuring this phenomenon using...... both physical and digital models at three distinct scales. The results suggest hyperboloid geometry, while difficult to fabricate, facilitates sound scattering....

  13. The influence of ski helmets on sound perception and sound localisation on the ski slope

    Directory of Open Access Journals (Sweden)

    Lana Ružić

    2015-04-01

    Full Text Available Objectives: The aim of the study was to investigate whether a ski helmet interferes with the sound localization and the time of sound perception in the frontal plane. Material and Methods: Twenty-three participants (age 30.7±10.2 were tested on the slope in 2 conditions, with and without wearing the ski helmet, by 6 different spatially distributed sound stimuli per each condition. Each of the subjects had to react when hearing the sound as soon as possible and to signalize the correct side of the sound arrival. Results: The results showed a significant difference in the ability to localize the specific ski sounds; 72.5±15.6% of correct answers without a helmet vs. 61.3±16.2% with a helmet (p < 0.01. However, the performance on this test did not depend on whether they were used to wearing a helmet (p = 0.89. In identifying the timing, at which the sound was firstly perceived, the results were also in favor of the subjects not wearing a helmet. The subjects reported hearing the ski sound clues at 73.4±5.56 m without a helmet vs. 60.29±6.34 m with a helmet (p < 0.001. In that case the results did depend on previously used helmets (p < 0.05, meaning that that regular usage of helmets might help to diminish the attenuation of the sound identification that occurs because of the helmets. Conclusions: Ski helmets might limit the ability of a skier to localize the direction of the sounds of danger and might interfere with the moment, in which the sound is firstly heard.

  14. 77 FR 37318 - Eighth Coast Guard District Annual Safety Zones; Sound of Independence; Santa Rosa Sound; Fort...

    Science.gov (United States)

    2012-06-21

    ...-AA00 Eighth Coast Guard District Annual Safety Zones; Sound of Independence; Santa Rosa Sound; Fort... Coast Guard will enforce a Safety Zone for the Sound of Independence event in the Santa Rosa Sound, Fort... during the Sound of Independence. During the enforcement period, entry into, transiting or anchoring in...

  15. Material sound source localization through headphones

    Science.gov (United States)

    Dunai, Larisa; Peris-Fajarnes, Guillermo; Lengua, Ismael Lengua; Montaña, Ignacio Tortajada

    2012-09-01

    In the present paper a study of sound localization is carried out, considering two different sounds emitted from different hit materials (wood and bongo) as well as a Delta sound. The motivation of this research is to study how humans localize sounds coming from different materials, with the purpose of a future implementation of the acoustic sounds with better localization features in navigation aid systems or training audio-games suited for blind people. Wood and bongo sounds are recorded after hitting two objects made of these materials. Afterwards, they are analysed and processed. On the other hand, the Delta sound (click) is generated by using the Adobe Audition software, considering a frequency of 44.1 kHz. All sounds are analysed and convolved with previously measured non-individual Head-Related Transfer Functions both for an anechoic environment and for an environment with reverberation. The First Choice method is used in this experiment. Subjects are asked to localize the source position of the sound listened through the headphones, by using a graphic user interface. The analyses of the recorded data reveal that no significant differences are obtained either when considering the nature of the sounds (wood, bongo, Delta) or their environmental context (with or without reverberation). The localization accuracies for the anechoic sounds are: wood 90.19%, bongo 92.96% and Delta sound 89.59%, whereas for the sounds with reverberation the results are: wood 90.59%, bongo 92.63% and Delta sound 90.91%. According to these data, we can conclude that even when considering the reverberation effect, the localization accuracy does not significantly increase.

  16. Waveform analysis of sound

    CERN Document Server

    Tohyama, Mikio

    2015-01-01

    What is this sound? What does that sound indicate? These are two questions frequently heard in daily conversation. Sound results from the vibrations of elastic media and in daily life provides informative signals of events happening in the surrounding environment. In interpreting auditory sensations, the human ear seems particularly good at extracting the signal signatures from sound waves. Although exploring auditory processing schemes may be beyond our capabilities, source signature analysis is a very attractive area in which signal-processing schemes can be developed using mathematical expressions. This book is inspired by such processing schemes and is oriented to signature analysis of waveforms. Most of the examples in the book are taken from data of sound and vibrations; however, the methods and theories are mostly formulated using mathematical expressions rather than by acoustical interpretation. This book might therefore be attractive and informative for scientists, engineers, researchers, and graduat...

  17. Sound Settlements

    DEFF Research Database (Denmark)

    Mortensen, Peder Duelund; Hornyanszky, Elisabeth Dalholm; Larsen, Jacob Norvig

    2013-01-01

    Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice......Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice...

  18. Sounds of silence: How to animate virtual worlds with sound

    Science.gov (United States)

    Astheimer, Peter

    1993-01-01

    Sounds are an integral and sometimes annoying part of our daily life. Virtual worlds which imitate natural environments gain a lot of authenticity from fast, high quality visualization combined with sound effects. Sounds help to increase the degree of immersion for human dwellers in imaginary worlds significantly. The virtual reality toolkit of IGD (Institute for Computer Graphics) features a broad range of standard visual and advanced real-time audio components which interpret an object-oriented definition of the scene. The virtual reality system 'Virtual Design' realized with the toolkit enables the designer of virtual worlds to create a true audiovisual environment. Several examples on video demonstrate the usage of the audio features in Virtual Design.

  19. How Pleasant Sounds Promote and Annoying Sounds Impede Health: A Cognitive Approach

    Directory of Open Access Journals (Sweden)

    Tjeerd C. Andringa

    2013-04-01

    Full Text Available This theoretical paper addresses the cognitive functions via which quiet and in general pleasurable sounds promote and annoying sounds impede health. The article comprises a literature analysis and an interpretation of how the bidirectional influence of appraising the environment and the feelings of the perceiver can be understood in terms of core affect and motivation. This conceptual basis allows the formulation of a detailed cognitive model describing how sonic content, related to indicators of safety and danger, either allows full freedom over mind-states or forces the activation of a vigilance function with associated arousal. The model leads to a number of detailed predictions that can be used to provide existing soundscape approaches with a solid cognitive science foundation that may lead to novel approaches to soundscape design. These will take into account that louder sounds typically contribute to distal situational awareness while subtle environmental sounds provide proximal situational awareness. The role of safety indicators, mediated by proximal situational awareness and subtle sounds, should become more important in future soundscape research.

  20. Sound synthesis and evaluation of interactive footsteps and environmental sounds rendering for virtual reality applications.

    Science.gov (United States)

    Nordahl, Rolf; Turchet, Luca; Serafin, Stefania

    2011-09-01

    We propose a system that affords real-time sound synthesis of footsteps on different materials. The system is based on microphones, which detect real footstep sounds from subjects, from which the ground reaction force (GRF) is estimated. Such GRF is used to control a sound synthesis engine based on physical models. Two experiments were conducted. In the first experiment, the ability of subjects to recognize the surface they were exposed to was assessed. In the second experiment, the sound synthesis engine was enhanced with environmental sounds. Results show that, in some conditions, adding a soundscape significantly improves the recognition of the simulated environment.

  1. It sounds good!

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Both the atmosphere and we ourselves are hit by hundreds of particles every second and yet nobody has ever heard a sound coming from these processes. Like cosmic rays, particles interacting inside the detectors at the LHC do not make any noise…unless you've decided to use the ‘sonification’ technique, in which case you might even hear the Higgs boson sound like music. Screenshot of the first page of the "LHC sound" site. A group of particle physicists, composers, software developers and artists recently got involved in the ‘LHC sound’ project to make the particles at the LHC produce music. Yes…music! The ‘sonification’ technique converts data into sound. “In this way, if you implement the right software you can get really nice music out of the particle tracks”, says Lily Asquith, a member of the ATLAS collaboration and one of the initiators of the project. The ‘LHC...

  2. Musical Sound, Instruments, and Equipment

    Science.gov (United States)

    Photinos, Panos

    2017-12-01

    'Musical Sound, Instruments, and Equipment' offers a basic understanding of sound, musical instruments and music equipment, geared towards a general audience and non-science majors. The book begins with an introduction of the fundamental properties of sound waves, and the perception of the characteristics of sound. The relation between intensity and loudness, and the relation between frequency and pitch are discussed. The basics of propagation of sound waves, and the interaction of sound waves with objects and structures of various sizes are introduced. Standing waves, harmonics and resonance are explained in simple terms, using graphics that provide a visual understanding. The development is focused on musical instruments and acoustics. The construction of musical scales and the frequency relations are reviewed and applied in the description of musical instruments. The frequency spectrum of selected instruments is explored using freely available sound analysis software. Sound amplification and sound recording, including analog and digital approaches, are discussed in two separate chapters. The book concludes with a chapter on acoustics, the physical factors that affect the quality of the music experience, and practical ways to improve the acoustics at home or small recording studios. A brief technical section is provided at the end of each chapter, where the interested reader can find the relevant physics and sample calculations. These quantitative sections can be skipped without affecting the comprehension of the basic material. Questions are provided to test the reader's understanding of the material. Answers are given in the appendix.

  3. Sound Velocity in Soap Foams

    International Nuclear Information System (INIS)

    Wu Gong-Tao; Lü Yong-Jun; Liu Peng-Fei; Li Yi-Ning; Shi Qing-Fan

    2012-01-01

    The velocity of sound in soap foams at high gas volume fractions is experimentally studied by using the time difference method. It is found that the sound velocities increase with increasing bubble diameter, and asymptotically approach to the value in air when the diameter is larger than 12.5 mm. We propose a simple theoretical model for the sound propagation in a disordered foam. In this model, the attenuation of a sound wave due to the scattering of the bubble wall is equivalently described as the effect of an additional length. This simplicity reasonably reproduces the sound velocity in foams and the predicted results are in good agreement with the experiments. Further measurements indicate that the increase of frequency markedly slows down the sound velocity, whereas the latter does not display a strong dependence on the solution concentration

  4. Numerical methods for axisymmetric and 3D nonlinear beams

    Science.gov (United States)

    Pinton, Gianmarco F.; Trahey, Gregg E.

    2005-04-01

    Time domain algorithms that solve the Khokhlov--Zabolotzskaya--Kuznetsov (KZK) equation are described and implemented. This equation represents the propagation of finite amplitude sound beams in a homogenous thermoviscous fluid for axisymmetric and fully three dimensional geometries. In the numerical solution each of the terms is considered separately and the numerical methods are compared with known solutions. First and second order operator splitting are used to combine the separate terms in the KZK equation and their convergence is examined.

  5. The magnetized electron-acoustic instability driven by a warm, field-aligned electron beam

    International Nuclear Information System (INIS)

    Sooklal, A.; Mace, R.L.

    2004-01-01

    The electron-acoustic instability in a magnetized plasma having three electron components, one of which is a field-aligned beam of intermediate temperature, is investigated. When the plasma frequency of the cool electrons exceeds the electron gyrofrequency, the electron-acoustic instability 'bifurcates' at sufficiently large propagation angles with respect to the magnetic field to yield an obliquely propagating, low-frequency electron-acoustic instability and a higher frequency cyclotron-sound instability. Each of these instabilities retains certain wave features of its progenitor, the quasiparallel electron-acoustic instability, but displays also new magnetic qualities through its dependence on the electron gyrofrequency. The obliquely propagating electron-acoustic instability requires a lower threshold beam speed for its excitation than does the cyclotron-sound instability, and for low to intermediate beam speeds has the higher maximum growth rate. When the plasma is sufficiently strongly magnetized that the plasma frequency of the cool electrons is less than the electron gyrofrequency, the only instability in the electron-acoustic frequency range is the strongly magnetized electron-acoustic instability. Its growth rate and real frequency exhibit a monotonic decrease with wave propagation angle and it grows at small to intermediate wave numbers where its parallel phase speed is approximately constant. The relevance of the results to the interpretation of cusp auroral hiss and auroral broadband electrostatic noise is briefly discussed

  6. OMNIDIRECTIONAL SOUND SOURCE

    DEFF Research Database (Denmark)

    1996-01-01

    A sound source comprising a loudspeaker (6) and a hollow coupler (4) with an open inlet which communicates with and is closed by the loudspeaker (6) and an open outlet, said coupler (4) comprising rigid walls which cannot respond to the sound pressures produced by the loudspeaker (6). According...

  7. The velocity of sound

    International Nuclear Information System (INIS)

    Beyer, R.T.

    1985-01-01

    The paper reviews the work carried out on the velocity of sound in liquid alkali metals. The experimental methods to determine the velocity measurements are described. Tables are presented of reported data on the velocity of sound in lithium, sodium, potassium, rubidium and caesium. A formula is given for alkali metals, in which the sound velocity is a function of shear viscosity, atomic mass and atomic volume. (U.K.)

  8. Product sounds : Fundamentals and application

    NARCIS (Netherlands)

    Ozcan-Vieira, E.

    2008-01-01

    Products are ubiquitous, so are the sounds emitted by products. Product sounds influence our reasoning, emotional state, purchase decisions, preference, and expectations regarding the product and the product's performance. Thus, auditory experience elicited by product sounds may not be just about

  9. Using data crawlers and semantic Web to build financial XBRL data generators: the SONAR extension approach.

    Science.gov (United States)

    Rodríguez-García, Miguel Ángel; Rodríguez-González, Alejandro; Colomo-Palacios, Ricardo; Valencia-García, Rafael; Gómez-Berbís, Juan Miguel; García-Sánchez, Francisco

    2014-01-01

    Precise, reliable and real-time financial information is critical for added-value financial services after the economic turmoil from which markets are still struggling to recover. Since the Web has become the most significant data source, intelligent crawlers based on Semantic Technologies have become trailblazers in the search of knowledge combining natural language processing and ontology engineering techniques. In this paper, we present the SONAR extension approach, which will leverage the potential of knowledge representation by extracting, managing, and turning scarce and disperse financial information into well-classified, structured, and widely used XBRL format-oriented knowledge, strongly supported by a proof-of-concept implementation and a thorough evaluation of the benefits of the approach.

  10. Using Data Crawlers and Semantic Web to Build Financial XBRL Data Generators: The SONAR Extension Approach

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Rodríguez-García

    2014-01-01

    Full Text Available Precise, reliable and real-time financial information is critical for added-value financial services after the economic turmoil from which markets are still struggling to recover. Since the Web has become the most significant data source, intelligent crawlers based on Semantic Technologies have become trailblazers in the search of knowledge combining natural language processing and ontology engineering techniques. In this paper, we present the SONAR extension approach, which will leverage the potential of knowledge representation by extracting, managing, and turning scarce and disperse financial information into well-classified, structured, and widely used XBRL format-oriented knowledge, strongly supported by a proof-of-concept implementation and a thorough evaluation of the benefits of the approach.

  11. Using Data Crawlers and Semantic Web to Build Financial XBRL Data Generators: The SONAR Extension Approach

    Science.gov (United States)

    Rodríguez-García, Miguel Ángel; Rodríguez-González, Alejandro; Valencia-García, Rafael; Gómez-Berbís, Juan Miguel

    2014-01-01

    Precise, reliable and real-time financial information is critical for added-value financial services after the economic turmoil from which markets are still struggling to recover. Since the Web has become the most significant data source, intelligent crawlers based on Semantic Technologies have become trailblazers in the search of knowledge combining natural language processing and ontology engineering techniques. In this paper, we present the SONAR extension approach, which will leverage the potential of knowledge representation by extracting, managing, and turning scarce and disperse financial information into well-classified, structured, and widely used XBRL format-oriented knowledge, strongly supported by a proof-of-concept implementation and a thorough evaluation of the benefits of the approach. PMID:24587726

  12. Suppression of sound radiation to far field of near-field acoustic communication system using evanescent sound field

    Science.gov (United States)

    Fujii, Ayaka; Wakatsuki, Naoto; Mizutani, Koichi

    2016-01-01

    A method of suppressing sound radiation to the far field of a near-field acoustic communication system using an evanescent sound field is proposed. The amplitude of the evanescent sound field generated from an infinite vibrating plate attenuates exponentially with increasing a distance from the surface of the vibrating plate. However, a discontinuity of the sound field exists at the edge of the finite vibrating plate in practice, which broadens the wavenumber spectrum. A sound wave radiates over the evanescent sound field because of broadening of the wavenumber spectrum. Therefore, we calculated the optimum distribution of the particle velocity on the vibrating plate to reduce the broadening of the wavenumber spectrum. We focused on a window function that is utilized in the field of signal analysis for reducing the broadening of the frequency spectrum. The optimization calculation is necessary for the design of window function suitable for suppressing sound radiation and securing a spatial area for data communication. In addition, a wide frequency bandwidth is required to increase the data transmission speed. Therefore, we investigated a suitable method for calculating the sound pressure level at the far field to confirm the variation of the distribution of sound pressure level determined on the basis of the window shape and frequency. The distribution of the sound pressure level at a finite distance was in good agreement with that obtained at an infinite far field under the condition generating the evanescent sound field. Consequently, the window function was optimized by the method used to calculate the distribution of the sound pressure level at an infinite far field using the wavenumber spectrum on the vibrating plate. According to the result of comparing the distributions of the sound pressure level in the cases with and without the window function, it was confirmed that the area whose sound pressure level was reduced from the maximum level to -50 dB was

  13. Habitat information in the region on the underwater San Andreas Fault - Topic: Exploring the Undersea San Andreas Fault: Revealing the Past, Present, and Future at the Centennial of the Great 1906 Earthquake

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — During this exploration, the first comprehensive high-resolution multi-beam sonar and seismic reflection survey of the Northern San Andreas Fault (NSAF) was...

  14. 33 CFR 334.410 - Albemarle Sound, Pamlico Sound, and adjacent waters, NC; danger zones for naval aircraft operations.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Albemarle Sound, Pamlico Sound... AND RESTRICTED AREA REGULATIONS § 334.410 Albemarle Sound, Pamlico Sound, and adjacent waters, NC; danger zones for naval aircraft operations. (a) Target areas—(1) North Landing River (Currituck Sound...

  15. Simulation of Sound Waves Using the Lattice Boltzmann Method for Fluid Flow: Benchmark Cases for Outdoor Sound Propagation.

    Science.gov (United States)

    Salomons, Erik M; Lohman, Walter J A; Zhou, Han

    2016-01-01

    Propagation of sound waves in air can be considered as a special case of fluid dynamics. Consequently, the lattice Boltzmann method (LBM) for fluid flow can be used for simulating sound propagation. In this article application of the LBM to sound propagation is illustrated for various cases: free-field propagation, propagation over porous and non-porous ground, propagation over a noise barrier, and propagation in an atmosphere with wind. LBM results are compared with solutions of the equations of acoustics. It is found that the LBM works well for sound waves, but dissipation of sound waves with the LBM is generally much larger than real dissipation of sound waves in air. To circumvent this problem it is proposed here to use the LBM for assessing the excess sound level, i.e. the difference between the sound level and the free-field sound level. The effect of dissipation on the excess sound level is much smaller than the effect on the sound level, so the LBM can be used to estimate the excess sound level for a non-dissipative atmosphere, which is a useful quantity in atmospheric acoustics. To reduce dissipation in an LBM simulation two approaches are considered: i) reduction of the kinematic viscosity and ii) reduction of the lattice spacing.

  16. Sounding out the logo shot

    OpenAIRE

    Nicolai Jørgensgaard Graakjær

    2013-01-01

    This article focuses on how sound in combination with visuals (i.e. ‘branding by’) may possibly affect the signifying potentials (i.e. ‘branding effect’) of products and corporate brands (i.e. ‘branding of’) during logo shots in television commercials (i.e. ‘branding through’). This particular focus adds both to the understanding of sound in television commercials and to the understanding of sound brands. The article firstly presents a typology of sounds. Secondly, this typology is applied...

  17. Sound intensity

    DEFF Research Database (Denmark)

    Crocker, Malcolm J.; Jacobsen, Finn

    1998-01-01

    This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique.......This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique....

  18. Sound Intensity

    DEFF Research Database (Denmark)

    Crocker, M.J.; Jacobsen, Finn

    1997-01-01

    This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique.......This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique....

  19. SoleSound

    DEFF Research Database (Denmark)

    Zanotto, Damiano; Turchet, Luca; Boggs, Emily Marie

    2014-01-01

    This paper introduces the design of SoleSound, a wearable system designed to deliver ecological, audio-tactile, underfoot feedback. The device, which primarily targets clinical applications, uses an audio-tactile footstep synthesis engine informed by the readings of pressure and inertial sensors...... embedded in the footwear to integrate enhanced feedback modalities into the authors' previously developed instrumented footwear. The synthesis models currently implemented in the SoleSound simulate different ground surface interactions. Unlike similar devices, the system presented here is fully portable...

  20. Sound engineering for diesel engines; Sound Engineering an Dieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Enderich, A.; Fischer, R. [MAHLE Filtersysteme GmbH, Stuttgart (Germany)

    2006-07-01

    The strong acceptance for vehicles powered by turbo-charged diesel engines encourages several manufacturers to think about sportive diesel concepts. The approach of suppressing unpleasant noise by the application of distinctive insulation steps is not adequate to satisfy sportive needs. The acoustics cannot follow the engine's performance. This report documents, that it is possible to give diesel-powered vehicles a sportive sound characteristic by using an advanced MAHLE motor-sound-system with a pressure-resistant membrane and an integrated load controlled flap. With this the specific acoustic disadvantages of the diesel engine, like the ''diesel knock'' or a rough engine running can be masked. However, by the application of a motor-sound-system you must not negate the original character of the diesel engine concept, but accentuate its strong torque characteristic in the middle engine speed range. (orig.)

  1. Sonic mediations: body, sound, technology

    NARCIS (Netherlands)

    Birdsall, C.; Enns, A.

    2008-01-01

    Sonic Mediations: Body, Sound, Technology is a collection of original essays that represents an invaluable contribution to the burgeoning field of sound studies. While sound is often posited as having a bridging function, as a passive in-between, this volume invites readers to rethink the concept of

  2. System for actively reducing sound

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2005-01-01

    A system for actively reducing sound from a primary noise source, such as traffic noise, comprising: a loudspeaker connector for connecting to at least one loudspeaker for generating anti-sound for reducing said noisy sound; a microphone connector for connecting to at least a first microphone placed

  3. Measuring the 'complexity'of sound

    Indian Academy of Sciences (India)

    Sounds in the natural environment form an important class of biologically relevant nonstationary signals. We propose a dynamic spectral measure to characterize the spectral dynamics of such non-stationary sound signals and classify them based on rate of change of spectral dynamics. We categorize sounds with slowly ...

  4. Controlling sound with acoustic metamaterials

    DEFF Research Database (Denmark)

    Cummer, Steven A. ; Christensen, Johan; Alù, Andrea

    2016-01-01

    Acoustic metamaterials can manipulate and control sound waves in ways that are not possible in conventional materials. Metamaterials with zero, or even negative, refractive index for sound offer new possibilities for acoustic imaging and for the control of sound at subwavelength scales....... The combination of transformation acoustics theory and highly anisotropic acoustic metamaterials enables precise control over the deformation of sound fields, which can be used, for example, to hide or cloak objects from incident acoustic energy. Active acoustic metamaterials use external control to create......-scale metamaterial structures and converting laboratory experiments into useful devices. In this Review, we outline the designs and properties of materials with unusual acoustic parameters (for example, negative refractive index), discuss examples of extreme manipulation of sound and, finally, provide an overview...

  5. Beam-Beam Effects

    International Nuclear Information System (INIS)

    Herr, W; Pieloni, T

    2014-01-01

    One of the most severe limitations in high-intensity particle colliders is the beam-beam interaction, i.e. the perturbation of the beams as they cross the opposing beams. This introduction to beam-beam effects concentrates on a description of the phenomena that are present in modern colliding beam facilities

  6. Sound intensity as a function of sound insulation partition

    OpenAIRE

    Cvetkovic , S.; Prascevic , R.

    1994-01-01

    In the modern engineering practice, the sound insulation of the partitions is the synthesis of the theory and of the experience acquired in the procedure of the field and of the laboratory measurement. The science and research public treat the sound insulation in the context of the emission and propagation of the acoustic energy in the media with the different acoustics impedance. In this paper, starting from the essence of physical concept of the intensity as the energy vector, the authors g...

  7. Okeanos Explorer (EX1403): East Coast Mapping and Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam, single beam, and subbottom sonar data will be collected 24 hours a day. XBT casts will be conducted regularly for multibeam calibration. The ship's...

  8. Okeanos Explorer (EX1402L3): Gulf of Mexico Mapping and ROV Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam mapping, single beam, water column sonar, sub-bottom profile, water column profile, ship sensor, ROV sensor, video and image data will all be collected...

  9. Heart Sound Localization and Reduction in Tracheal Sounds by Gabor Time-Frequency Masking

    OpenAIRE

    SAATCI, Esra; Akan, Aydın

    2018-01-01

    Background and aim: Respiratorysounds, i.e. tracheal and lung sounds, have been of great interest due to theirdiagnostic values as well as the potential of their use in the estimation ofthe respiratory dynamics (mainly airflow). Thus the aim of the study is topresent a new method to filter the heart sound interference from the trachealsounds. Materials and methods: Trachealsounds and airflow signals were collected by using an accelerometer from 10 healthysubjects. Tracheal sounds were then pr...

  10. Interactive physically-based sound simulation

    Science.gov (United States)

    Raghuvanshi, Nikunj

    The realization of interactive, immersive virtual worlds requires the ability to present a realistic audio experience that convincingly compliments their visual rendering. Physical simulation is a natural way to achieve such realism, enabling deeply immersive virtual worlds. However, physically-based sound simulation is very computationally expensive owing to the high-frequency, transient oscillations underlying audible sounds. The increasing computational power of desktop computers has served to reduce the gap between required and available computation, and it has become possible to bridge this gap further by using a combination of algorithmic improvements that exploit the physical, as well as perceptual properties of audible sounds. My thesis is a step in this direction. My dissertation concentrates on developing real-time techniques for both sub-problems of sound simulation: synthesis and propagation. Sound synthesis is concerned with generating the sounds produced by objects due to elastic surface vibrations upon interaction with the environment, such as collisions. I present novel techniques that exploit human auditory perception to simulate scenes with hundreds of sounding objects undergoing impact and rolling in real time. Sound propagation is the complementary problem of modeling the high-order scattering and diffraction of sound in an environment as it travels from source to listener. I discuss my work on a novel numerical acoustic simulator (ARD) that is hundred times faster and consumes ten times less memory than a high-accuracy finite-difference technique, allowing acoustic simulations on previously-intractable spaces, such as a cathedral, on a desktop computer. Lastly, I present my work on interactive sound propagation that leverages my ARD simulator to render the acoustics of arbitrary static scenes for multiple moving sources and listener in real time, while accounting for scene-dependent effects such as low-pass filtering and smooth attenuation

  11. 27 CFR 9.151 - Puget Sound.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Puget Sound. 9.151 Section... Sound. (a) Name. The name of the viticultural area described in this section is “Puget Sound.” (b) Approved maps. The appropriate maps for determining the boundary of the Puget Sound viticultural area are...

  12. How Pleasant Sounds Promote and Annoying Sounds Impede Health : A Cognitive Approach

    NARCIS (Netherlands)

    Andringa, Tjeerd C.; Lanser, J. Jolie L.

    2013-01-01

    This theoretical paper addresses the cognitive functions via which quiet and in general pleasurable sounds promote and annoying sounds impede health. The article comprises a literature analysis and an interpretation of how the bidirectional influence of appraising the environment and the feelings of

  13. Of Sound Mind: Mental Distress and Sound in Twentieth-Century Media Culture

    NARCIS (Netherlands)

    Birdsall, C.; Siewert, S.

    2013-01-01

    This article seeks to specify the representation of mental disturbance in sound media during the twentieth century. It engages perspectives on societal and technological change across the twentieth century as crucial for aesthetic strategies developed in radio and sound film production. The analysis

  14. Sounds scary? Lack of habituation following the presentation of novel sounds.

    Directory of Open Access Journals (Sweden)

    Tine A Biedenweg

    Full Text Available BACKGROUND: Animals typically show less habituation to biologically meaningful sounds than to novel signals. We might therefore expect that acoustic deterrents should be based on natural sounds. METHODOLOGY: We investigated responses by western grey kangaroos (Macropus fulignosus towards playback of natural sounds (alarm foot stomps and Australian raven (Corvus coronoides calls and artificial sounds (faux snake hiss and bull whip crack. We then increased rate of presentation to examine whether animals would habituate. Finally, we varied frequency of playback to investigate optimal rates of delivery. PRINCIPAL FINDINGS: Nine behaviors clustered into five Principal Components. PC factors 1 and 2 (animals alert or looking, or hopping and moving out of area accounted for 36% of variance. PC factor 3 (eating cessation, taking flight, movement out of area accounted for 13% of variance. Factors 4 and 5 (relaxing, grooming and walking; 12 and 11% of variation, respectively discontinued upon playback. The whip crack was most evocative; eating was reduced from 75% of time spent prior to playback to 6% following playback (post alarm stomp: 32%, raven call: 49%, hiss: 75%. Additionally, 24% of individuals took flight and moved out of area (50 m radius in response to the whip crack (foot stomp: 0%, raven call: 8% and 4%, hiss: 6%. Increasing rate of presentation (12x/min ×2 min caused 71% of animals to move out of the area. CONCLUSIONS/SIGNIFICANCE: The bull whip crack, an artificial sound, was as effective as the alarm stomp at eliciting aversive behaviors. Kangaroos did not fully habituate despite hearing the signal up to 20x/min. Highest rates of playback did not elicit the greatest responses, suggesting that 'more is not always better'. Ultimately, by utilizing both artificial and biological sounds, predictability may be masked or offset, so that habituation is delayed and more effective deterrents may be produced.

  15. Sound localization and occupational noise

    Directory of Open Access Journals (Sweden)

    Pedro de Lemos Menezes

    2014-02-01

    Full Text Available OBJECTIVE: The aim of this study was to determine the effects of occupational noise on sound localization in different spatial planes and frequencies among normal hearing firefighters. METHOD: A total of 29 adults with pure-tone hearing thresholds below 25 dB took part in the study. The participants were divided into a group of 19 firefighters exposed to occupational noise and a control group of 10 adults who were not exposed to such noise. All subjects were assigned a sound localization task involving 117 stimuli from 13 sound sources that were spatially distributed in horizontal, vertical, midsagittal and transverse planes. The three stimuli, which were square waves with fundamental frequencies of 500, 2,000 and 4,000 Hz, were presented at a sound level of 70 dB and were randomly repeated three times from each sound source. The angle between the speaker's axis in the same plane was 45°, and the distance to the subject was 1 m. RESULT: The results demonstrate that the sound localization ability of the firefighters was significantly lower (p<0.01 than that of the control group. CONCLUSION: Exposure to occupational noise, even when not resulting in hearing loss, may lead to a diminished ability to locate a sound source.

  16. Plasma waves stimulated by electron beams in the lab and in the auroral ionosphere

    International Nuclear Information System (INIS)

    Holzworth, R.H.; Harbridge, W.B.; Koons, H.C.

    1982-01-01

    This chapter describes the experimental laboratory simulation of ionospheric rocket observed phenomena. The NASA sounding rocket 27.010 AE was launched in 1978 in order to study plasma dynamics in the auroral ionosphere. The rocket carried an electron accelerator and a full complement of plasma diagnostic devices including electric and magnetic receivers, particle detectors and photometers. The simulation was conducted in the large vacuum chamber at NASA's Johnson Space Center. The electron beam was operated at 4 kilovolts and the electron current modulated at 3 kiloherz from 0 to 80 milliamps during the rocket flight, resulting in the pulsing of the beam in and out of beam plasma discharge (BPD) and a variety of propagating wave modes. It is concluded that the electron-beam-produced BPD in the rocket is similar to that seen in the lab. The very low frequency (VLF) spectrum during BPD is examined

  17. The effect of sound speed profile on shallow water shipping sound maps

    NARCIS (Netherlands)

    Sertlek, H.Ö.; Binnerts, B.; Ainslie, M.A.

    2016-01-01

    Sound mapping over large areas can be computationally expensive because of the large number of sources and large source-receiver separations involved. In order to facilitate computation, a simplifying assumption sometimes made is to neglect the sound speed gradient in shallow water. The accuracy of

  18. Sound wave transmission (image)

    Science.gov (United States)

    When sounds waves reach the ear, they are translated into nerve impulses. These impulses then travel to the brain where they are interpreted by the brain as sound. The hearing mechanisms within the inner ear, can ...

  19. Sound & The Society

    DEFF Research Database (Denmark)

    Schulze, Holger

    2014-01-01

    How are those sounds you hear right now socially constructed and evaluated, how are they architecturally conceptualized and how dependant on urban planning, industrial developments and political decisions are they really? How is your ability to hear intertwined with social interactions and their ...... and their professional design? And how is listening and sounding a deeply social activity – constructing our way of living together in cities as well as in apartment houses? A radio feature with Nina Backmann, Jochen Bonz, Stefan Krebs, Esther Schelander & Holger Schulze......How are those sounds you hear right now socially constructed and evaluated, how are they architecturally conceptualized and how dependant on urban planning, industrial developments and political decisions are they really? How is your ability to hear intertwined with social interactions...

  20. Predicting outdoor sound

    CERN Document Server

    Attenborough, Keith; Horoshenkov, Kirill

    2014-01-01

    1. Introduction  2. The Propagation of Sound Near Ground Surfaces in a Homogeneous Medium  3. Predicting the Acoustical Properties of Outdoor Ground Surfaces  4. Measurements of the Acoustical Properties of Ground Surfaces and Comparisons with Models  5. Predicting Effects of Source Characteristics on Outdoor Sound  6. Predictions, Approximations and Empirical Results for Ground Effect Excluding Meteorological Effects  7. Influence of Source Motion on Ground Effect and Diffraction  8. Predicting Effects of Mixed Impedance Ground  9. Predicting the Performance of Outdoor Noise Barriers  10. Predicting Effects of Vegetation, Trees and Turbulence  11. Analytical Approximations including Ground Effect, Refraction and Turbulence  12. Prediction Schemes  13. Predicting Sound in an Urban Environment.

  1. Okeanos Explorer (EX1609): Main Hawaiian Island Shakedown

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam, split-beam, and/or ADCP sonar mapping operations will be conducted 24 hours a day throughout the cruise. Sub-bottom profile mapping will be conducted...

  2. Importance of beam-beam tune spread to collective beam-beam instability in hadron colliders

    International Nuclear Information System (INIS)

    Jin Lihui; Shi Jicong

    2004-01-01

    In hadron colliders, electron-beam compensation of beam-beam tune spread has been explored for a reduction of beam-beam effects. In this paper, effects of the tune-spread compensation on beam-beam instabilities were studied with a self-consistent beam-beam simulation in model lattices of Tevatron and Large Hodron Collider. It was found that the reduction of the tune spread with the electron-beam compensation could induce a coherent beam-beam instability. The merit of the compensation with different degrees of tune-spread reduction was evaluated based on beam-size growth. When two beams have a same betatron tune, the compensation could do more harm than good to the beams when only beam-beam effects are considered. If a tune split between two beams is large enough, the compensation with a small reduction of the tune spread could benefit beams as Landau damping suppresses the coherent beam-beam instability. The result indicates that nonlinear (nonintegrable) beam-beam effects could dominate beam dynamics and a reduction of beam-beam tune spread by introducing additional beam-beam interactions and reducing Landau damping may not improve the stability of beams

  3. Sounds of Web Advertising

    DEFF Research Database (Denmark)

    Jessen, Iben Bredahl; Graakjær, Nicolai Jørgensgaard

    2010-01-01

    Sound seems to be a neglected issue in the study of web ads. Web advertising is predominantly regarded as visual phenomena–commercial messages, as for instance banner ads that we watch, read, and eventually click on–but only rarely as something that we listen to. The present chapter presents...... an overview of the auditory dimensions in web advertising: Which kinds of sounds do we hear in web ads? What are the conditions and functions of sound in web ads? Moreover, the chapter proposes a theoretical framework in order to analyse the communicative functions of sound in web advertising. The main...... argument is that an understanding of the auditory dimensions in web advertising must include a reflection on the hypertextual settings of the web ad as well as a perspective on how users engage with web content....

  4. The Aesthetic Experience of Sound

    DEFF Research Database (Denmark)

    Breinbjerg, Morten

    2005-01-01

    to react on. In an ecological understanding of hearing our detection of audible information affords us ways of responding to our environment. In my paper I will address both these ways of using sound in relation to computer games. Since a game player is responsible for the unfolding of the game, his......The use of sound in (3D) computer games basically falls in two. Sound is used as an element in the design of the set and as a narrative. As set design sound stages the nature of the environment, it brings it to life. As a narrative it brings us information that we can choose to or perhaps need...... exploration of the virtual space laid out before him is pertinent. In this mood of exploration sound is important and heavily contributing to the aesthetic of the experience....

  5. Sounding the field: recent works in sound studies.

    Science.gov (United States)

    Boon, Tim

    2015-09-01

    For sound studies, the publication of a 593-page handbook, not to mention the establishment of at least one society - the European Sound Studies Association - might seem to signify the emergence of a new academic discipline. Certainly, the books under consideration here, alongside many others, testify to an intensification of concern with the aural dimensions of culture. Some of this work comes from HPS and STS, some from musicology and cultural studies. But all of it should concern members of our disciplines, as it represents a long-overdue foregrounding of the aural in how we think about the intersections of science, technology and culture.

  6. Sound Clocks and Sonic Relativity

    Science.gov (United States)

    Todd, Scott L.; Menicucci, Nicolas C.

    2017-10-01

    Sound propagation within certain non-relativistic condensed matter models obeys a relativistic wave equation despite such systems admitting entirely non-relativistic descriptions. A natural question that arises upon consideration of this is, "do devices exist that will experience the relativity in these systems?" We describe a thought experiment in which `acoustic observers' possess devices called sound clocks that can be connected to form chains. Careful investigation shows that appropriately constructed chains of stationary and moving sound clocks are perceived by observers on the other chain as undergoing the relativistic phenomena of length contraction and time dilation by the Lorentz factor, γ , with c the speed of sound. Sound clocks within moving chains actually tick less frequently than stationary ones and must be separated by a shorter distance than when stationary to satisfy simultaneity conditions. Stationary sound clocks appear to be length contracted and time dilated to moving observers due to their misunderstanding of their own state of motion with respect to the laboratory. Observers restricted to using sound clocks describe a universe kinematically consistent with the theory of special relativity, despite the preferred frame of their universe in the laboratory. Such devices show promise in further probing analogue relativity models, for example in investigating phenomena that require careful consideration of the proper time elapsed for observers.

  7. Non-Wovens as Sound Reducers

    Science.gov (United States)

    Belakova, D.; Seile, A.; Kukle, S.; Plamus, T.

    2018-04-01

    Within the present study, the effect of hemp (40 wt%) and polyactide (60 wt%), non-woven surface density, thickness and number of fibre web layers on the sound absorption coefficient and the sound transmission loss in the frequency range from 50 to 5000 Hz is analysed. The sound insulation properties of the experimental samples have been determined, compared to the ones in practical use, and the possible use of material has been defined. Non-woven materials are ideally suited for use in acoustic insulation products because the arrangement of fibres produces a porous material structure, which leads to a greater interaction between sound waves and fibre structure. Of all the tested samples (A, B and D), the non-woven variant B exceeded the surface density of sample A by 1.22 times and 1.15 times that of sample D. By placing non-wovens one above the other in 2 layers, it is possible to increase the absorption coefficient of the material, which depending on the frequency corresponds to C, D, and E sound absorption classes. Sample A demonstrates the best sound absorption of all the three samples in the frequency range from 250 to 2000 Hz. In the test frequency range from 50 to 5000 Hz, the sound transmission loss varies from 0.76 (Sample D at 63 Hz) to 3.90 (Sample B at 5000 Hz).

  8. Sounds of Space

    Science.gov (United States)

    Gurnett, D. A.

    2005-12-01

    Starting in the early 1960s, spacecraft-borne plasma wave instruments revealed that space is filled with an astonishing variety of radio and plasma wave sounds, which have come to be called "sounds of space." For over forty years these sounds have been collected and played to a wide variety of audiences, often as the result of press conferences or press releases involving various NASA projects for which the University of Iowa has provided plasma wave instruments. This activity has led to many interviews on local and national radio programs, and occasionally on programs haviang world-wide coverage, such as the BBC. As a result of this media coverage, we have been approached many times by composers requesting copies of our space sounds for use in their various projects, many of which involve electronic synthesis of music. One of these collaborations led to "Sun Rings," which is a musical event produced by the Kronos Quartet that has played to large audiences all over the world. With the availability of modern computer graphic techniques we have recently been attempting to integrate some of these sound of space into an educational audio/video web site that illustrates the scientific principles involved in the origin of space plasma waves. Typically I try to emphasize that a substantial gas pressure exists everywhere in space in the form of an ionized gas called a plasma, and that this plasma can lead to a wide variety of wave phenomenon. Examples of some of this audio/video material will be presented.

  9. Sound Synthesis and Evaluation of Interactive Footsteps and Environmental Sounds Rendering for Virtual Reality Applications

    DEFF Research Database (Denmark)

    Nordahl, Rolf; Turchet, Luca; Serafin, Stefania

    2011-01-01

    We propose a system that affords real-time sound synthesis of footsteps on different materials. The system is based on microphones, which detect real footstep sounds from subjects, from which the ground reaction force (GRF) is estimated. Such GRF is used to control a sound synthesis engine based ...... a soundscape significantly improves the recognition of the simulated environment....

  10. Characteristics of a sandy depositional lobe on the outer Mississippi fan from SeaMARC IA sidescan sonar images

    Science.gov (United States)

    Twichell, David C.; Schwab, William C.; Nelson, C. Hans; Kenyon, Neil H.; Lee, Homa J.

    1992-01-01

    SeaMARC IA sidescan sonar images of the distal reaches of a depositional lobe on the Mississippi Fan show that channelized rather than unconfined transport was the dominant transport mechanism for coarse-grained sediment during the formation of this part of the deep-sea fan. Overbank sheet flow of sands was not an important process in the transport and deposition of the sandy and silty sediment found on this fan. The dendritic distributary pattern and the high order of splaying of the channels, only one of which appears to have been active at a time, suggest that coarse-grained deposits on this fan are laterally discontinuous.

  11. Okeanos Explorer (EX1404L1): Shakedown and Mapping, NE Seamounts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam, single beam, and subbottom sonar data will be collected 24 hours a day and XBT casts will be conducted at an interval defined by prevailing oceanographic...

  12. Oceanographic data collected during the EX1404L1 (Shakedown and Mapping, NE Seamounts) expedition on NOAA Ship OKEANOS EXPLORER in the North Atlantic Ocean from 2014-08-09 to 2014-08-30 (NCEI Accession 0121584)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam, single beam, and subbottom sonar data will be collected 24 hours a day and XBT casts will be conducted at an interval defined by prevailing oceanographic...

  13. Using therapeutic sound with progressive audiologic tinnitus management.

    Science.gov (United States)

    Henry, James A; Zaugg, Tara L; Myers, Paula J; Schechter, Martin A

    2008-09-01

    Management of tinnitus generally involves educational counseling, stress reduction, and/or the use of therapeutic sound. This article focuses on therapeutic sound, which can involve three objectives: (a) producing a sense of relief from tinnitus-associated stress (using soothing sound); (b) passively diverting attention away from tinnitus by reducing contrast between tinnitus and the acoustic environment (using background sound); and (c) actively diverting attention away from tinnitus (using interesting sound). Each of these goals can be accomplished using three different types of sound-broadly categorized as environmental sound, music, and speech-resulting in nine combinations of uses of sound and types of sound to manage tinnitus. The authors explain the uses and types of sound, how they can be combined, and how the different combinations are used with Progressive Audiologic Tinnitus Management. They also describe how sound is used with other sound-based methods of tinnitus management (Tinnitus Masking, Tinnitus Retraining Therapy, and Neuromonics).

  14. Letter-Sound Knowledge: Exploring Gender Differences in Children When They Start School Regarding Knowledge of Large Letters, Small Letters, Sound Large Letters, and Sound Small Letters

    Directory of Open Access Journals (Sweden)

    Hermundur Sigmundsson

    2017-09-01

    Full Text Available This study explored whether there is a gender difference in letter-sound knowledge when children start at school. 485 children aged 5–6 years completed assessment of letter-sound knowledge, i.e., large letters; sound of large letters; small letters; sound of small letters. The findings indicate a significant difference between girls and boys in all four factors tested in this study in favor of the girls. There are still no clear explanations to the basis of a presumed gender difference in letter-sound knowledge. That the findings have origin in neuro-biological factors cannot be excluded, however, the fact that girls probably have been exposed to more language experience/stimulation compared to boys, lends support to explanations derived from environmental aspects.

  15. ''Accelerators and Beams,'' multimedia computer-based training in accelerator physics

    International Nuclear Information System (INIS)

    Silbar, R. R.; Browman, A. A.; Mead, W. C.; Williams, R. A.

    1999-01-01

    We are developing a set of computer-based tutorials on accelerators and charged-particle beams under an SBIR grant from the DOE. These self-paced, interactive tutorials, available for Macintosh and Windows platforms, use multimedia techniques to enhance the user's rate of learning and length of retention of the material. They integrate interactive ''On-Screen Laboratories,'' hypertext, line drawings, photographs, two- and three-dimensional animations, video, and sound. They target a broad audience, from undergraduates or technicians to professionals. Presently, three modules have been published (Vectors, Forces, and Motion), a fourth (Dipole Magnets) has been submitted for review, and three more exist in prototype form (Quadrupoles, Matrix Transport, and Properties of Charged-Particle Beams). Participants in the poster session will have the opportunity to try out these modules on a laptop computer

  16. By the sound of it. An ERP investigation of human action sound processing in 7-month-old infants

    Directory of Open Access Journals (Sweden)

    Elena Geangu

    2015-04-01

    Full Text Available Recent evidence suggests that human adults perceive human action sounds as a distinct category from human vocalizations, environmental, and mechanical sounds, activating different neural networks (Engel et al., 2009; Lewis et al., 2011. Yet, little is known about the development of such specialization. Using event-related potentials (ERP, this study investigated neural correlates of 7-month-olds’ processing of human action (HA sounds in comparison to human vocalizations (HV, environmental (ENV, and mechanical (MEC sounds. Relative to the other categories, HA sounds led to increased positive amplitudes between 470 and 570 ms post-stimulus onset at left anterior temporal locations, while HV led to increased negative amplitudes at the more posterior temporal locations in both hemispheres. Collectively, human produced sounds (HA + HV led to significantly different response profiles compared to non-living sound sources (ENV + MEC at parietal and frontal locations in both hemispheres. Overall, by 7 months of age human action sounds are being differentially processed in the brain, consistent with a dichotomy for processing living versus non-living things. This provides novel evidence regarding the typical categorical processing of socially relevant sounds.

  17. Sound as Popular Culture

    DEFF Research Database (Denmark)

    The wide-ranging texts in this book take as their premise the idea that sound is a subject through which popular culture can be analyzed in an innovative way. From an infant’s gurgles over a baby monitor to the roar of the crowd in a stadium to the sub-bass frequencies produced by sound systems...... in the disco era, sound—not necessarily aestheticized as music—is inextricably part of the many domains of popular culture. Expanding the view taken by many scholars of cultural studies, the contributors consider cultural practices concerning sound not merely as semiotic or signifying processes but as material......, physical, perceptual, and sensory processes that integrate a multitude of cultural traditions and forms of knowledge. The chapters discuss conceptual issues as well as terminologies and research methods; analyze historical and contemporary case studies of listening in various sound cultures; and consider...

  18. Fourth sound in relativistic superfluidity theory

    International Nuclear Information System (INIS)

    Vil'chinskij, S.I.; Fomin, P.I.

    1995-01-01

    The Lorentz-covariant equations describing propagation of the fourth sound in the relativistic theory of superfluidity are derived. The expressions for the velocity of the fourth sound are obtained. The character of oscillation in sound is determined

  19. The science of sound recording

    CERN Document Server

    Kadis, Jay

    2012-01-01

    The Science of Sound Recording will provide you with more than just an introduction to sound and recording, it will allow you to dive right into some of the technical areas that often appear overwhelming to anyone without an electrical engineering or physics background.  The Science of Sound Recording helps you build a basic foundation of scientific principles, explaining how recording really works. Packed with valuable must know information, illustrations and examples of 'worked through' equations this book introduces the theory behind sound recording practices in a logical and prac

  20. Nuclear sound

    International Nuclear Information System (INIS)

    Wambach, J.

    1991-01-01

    Nuclei, like more familiar mechanical systems, undergo simple vibrational motion. Among these vibrations, sound modes are of particular interest since they reveal important information on the effective interactions among the constituents and, through extrapolation, on the bulk behaviour of nuclear and neutron matter. Sound wave propagation in nuclei shows strong quantum effects familiar from other quantum systems. Microscopic theory suggests that the restoring forces are caused by the complex structure of the many-Fermion wavefunction and, in some cases, have no classical analogue. The damping of the vibrational amplitude is strongly influenced by phase coherence among the particles participating in the motion. (author)

  1. Scanning behavior in echolocating common pipistrelle bats (Pipistrellus pipistrellus.

    Directory of Open Access Journals (Sweden)

    Anna-Maria Seibert

    Full Text Available Echolocating bats construct an auditory world sequentially by analyzing successive pulse-echo pairs. Many other mammals rely upon a visual world, acquired by sequential foveal fixations connected by visual gaze saccades. We investigated the scanning behavior of bats and compared it to visual scanning. We assumed that each pulse-echo pair evaluation corresponds to a foveal fixation and that sonar beam movements between pulses can be seen as acoustic gaze saccades. We used a two-dimensional 16 microphone array to determine the sonar beam direction of succeeding pulses and to characterize the three dimensional scanning behavior in the common pipistrelle bat (Pipistrellus pipistrellus flying in the field. We also used variations of signal amplitude of single microphone recordings as indicator for scanning behavior in open space. We analyzed 33 flight sequences containing more than 700 echolocation calls to determine bat positions, source levels, and beam aiming. When searching for prey and orienting in space, bats moved their sonar beam in all directions, often alternately back and forth. They also produced sequences with irregular or no scanning movements. When approaching the array, the scanning movements were much smaller and the beam was moved over the array in small steps. Differences in the scanning pattern at various recording sites indicated that the scanning behavior depended on the echolocation task that was being performed. The scanning angles varied over a wide range and were often larger than the maximum angle measurable by our array. We found that echolocating bats use a "saccade and fixate" strategy similar to vision. Through the use of scanning movements, bats are capable of finding and exploring targets in a wide search cone centered along flight direction.

  2. Students' Learning of a Generalized Theory of Sound Transmission from a Teaching-Learning Sequence about Sound, Hearing and Health

    Science.gov (United States)

    West, Eva; Wallin, Anita

    2013-04-01

    Learning abstract concepts such as sound often involves an ontological shift because to conceptualize sound transmission as a process of motion demands abandoning sound transmission as a transfer of matter. Thus, for students to be able to grasp and use a generalized model of sound transmission poses great challenges for them. This study involved 199 students aged 10-14. Their views about sound transmission were investigated before and after teaching by comparing their written answers about sound transfer in different media. The teaching was built on a research-based teaching-learning sequence (TLS), which was developed within a framework of design research. The analysis involved interpreting students' underlying theories of sound transmission, including the different conceptual categories that were found in their answers. The results indicated a shift in students' understandings from the use of a theory of matter before the intervention to embracing a theory of process afterwards. The described pattern was found in all groups of students irrespective of age. Thus, teaching about sound and sound transmission is fruitful already at the ages of 10-11. However, the older the students, the more advanced is their understanding of the process of motion. In conclusion, the use of a TLS about sound, hearing and auditory health promotes students' conceptualization of sound transmission as a process in all grades. The results also imply some crucial points in teaching and learning about the scientific content of sound.

  3. Numerical comparison of patch and sandwich piezoelectric transducers for transmitting ultrasonic waves

    CSIR Research Space (South Africa)

    Loveday, PW

    2006-03-01

    Full Text Available in the waveguide. Piezoelectric patch transducers are frequently employed, by researchers, for exciting waves in beam like structures. Sonar systems frequently make use of resonant transducers, such as sandwich transducers, for acoustic wave generation...

  4. Digitizing a sound archive

    DEFF Research Database (Denmark)

    Cone, Louise

    2017-01-01

    Danish and international artists. His methodology left us with a large collection of unique and inspirational time-based media sound artworks that have, until very recently, been inaccessible. Existing on an array of different media formats, such as open reel tapes, 8-track and 4 track cassettes, VHS......In 1990 an artist by the name of William Louis Sørensen was hired by the National Gallery of Denmark to collect important works of art – made from sound. His job was to acquire sound art, but also recordings that captured rare artistic occurrences, music, performances and happenings from both...

  5. Parallel-plate third sound waveguides with fixed and variable plate spacings for the study of fifth sound in superfluid helium

    International Nuclear Information System (INIS)

    Jelatis, G.J.

    1983-01-01

    Third sound in superfluid helium four films has been investigated using two parallel-plate waveguides. These investigations led to the observation of fifth sound, a new mode of sound propagation. Both waveguides consisted of two parallel pieces of vitreous quartz. The sound speed was obtained by measuring the time-of-flight of pulsed third sound over a known distance. Investigations from 1.0-1.7K were possible with the use of superconducting bolometers, which measure the temperature component of the third sound wave. Observations were initially made with a waveguide having a plate separation fixed at five microns. Adiabatic third sound was measured in the geometry. Isothermal third sound was also observed, using the usual, single-substrate technique. Fifth sound speeds, calculated from the two-fluid theory of helium and the speeds of the two forms of third sound, agreed in size and temperature dependence with theoretical predictions. Nevertheless, only equivocal observations of fifth sound were made. As a result, the film-substrate interaction was examined, and estimates of the Kapitza conductance were made. Assuming the dominance of the effects of this conductance over those due to the ECEs led to a new expression for fifth sound. A reanalysis of the initial data was made, which contained no adjustable parameters. The observation of fifth sound was seen to be consistent with the existence of an anomalously low boundary conductance

  6. Sound propagation in cities

    NARCIS (Netherlands)

    Salomons, E.; Polinder, H.; Lohman, W.; Zhou, H.; Borst, H.

    2009-01-01

    A new engineering model for sound propagation in cities is presented. The model is based on numerical and experimental studies of sound propagation between street canyons. Multiple reflections in the source canyon and the receiver canyon are taken into account in an efficient way, while weak

  7. Hamiltonian Algorithm Sound Synthesis

    OpenAIRE

    大矢, 健一

    2013-01-01

    Hamiltonian Algorithm (HA) is an algorithm for searching solutions is optimization problems. This paper introduces a sound synthesis technique using Hamiltonian Algorithm and shows a simple example. "Hamiltonian Algorithm Sound Synthesis" uses phase transition effect in HA. Because of this transition effect, totally new waveforms are produced.

  8. Exploring Noise: Sound Pollution.

    Science.gov (United States)

    Rillo, Thomas J.

    1979-01-01

    Part one of a three-part series about noise pollution and its effects on humans. This section presents the background information for teachers who are preparing a unit on sound. The next issues will offer learning activities for measuring the effects of sound and some references. (SA)

  9. Photoacoustic Sounds from Meteors.

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, Richard E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tencer, John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sweatt, William C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hogan, Roy E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Boslough, Mark B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Spurny, Pavel [Academy of Sciences of the Czech Republic (ASCR), Prague (Czech Republic)

    2015-03-01

    High-speed photometric observations of meteor fireballs have shown that they often produce high-amplitude light oscillations with frequency components in the kHz range, and in some cases exhibit strong millisecond flares. We built a light source with similar characteristics and illuminated various materials in the laboratory, generating audible sounds. Models suggest that light oscillations and pulses can radiatively heat dielectric materials, which in turn conductively heats the surrounding air on millisecond timescales. The sound waves can be heard if the illuminated material is sufficiently close to the observer’s ears. The mechanism described herein may explain many reports of meteors that appear to be audible while they are concurrently visible in the sky and too far away for sound to have propagated to the observer. This photoacoustic (PA) explanation provides an alternative to electrophonic (EP) sounds hypothesized to arise from electromagnetic coupling of plasma oscillation in the meteor wake to natural antennas in the vicinity of an observer.

  10. Urban Sound Interfaces

    DEFF Research Database (Denmark)

    Breinbjerg, Morten

    2012-01-01

    This paper draws on the theories of Michel de Certeau and Gaston Bachelard to discuss how media architecture, in the form of urban sound interfaces, can help us perceive the complexity of the spaces we inhabit, by exploring the history and the narratives of the places in which we live. In this pa......This paper draws on the theories of Michel de Certeau and Gaston Bachelard to discuss how media architecture, in the form of urban sound interfaces, can help us perceive the complexity of the spaces we inhabit, by exploring the history and the narratives of the places in which we live....... In this paper, three sound works are discussed in relation to the iPod, which is considered as a more private way to explore urban environments, and as a way to control the individual perception of urban spaces....

  11. Sound field separation with sound pressure and particle velocity measurements

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Jacobsen, Finn; Leclère, Quentin

    2012-01-01

    separation techniques make it possible to distinguish between outgoing and incoming waves from the two sides, and thus NAH can be applied. In this paper, a separation method based on the measurement of the particle velocity in two layers and another method based on the measurement of the pressure...... and the velocity in a single layer are proposed. The two methods use an equivalent source formulation with separate transfer matrices for the outgoing and incoming waves, so that the sound from the two sides of the array can be modeled independently. A weighting scheme is proposed to account for the distance......In conventional near-field acoustic holography (NAH) it is not possible to distinguish between sound from the two sides of the array, thus, it is a requirement that all the sources are confined to only one side and radiate into a free field. When this requirement cannot be fulfilled, sound field...

  12. Electromagnetic sounding of the Earth's interior

    CERN Document Server

    Spichak, Viacheslav V

    2015-01-01

    Electromagnetic Sounding of the Earth's Interior 2nd edition provides a comprehensive up-to-date collection of contributions, covering methodological, computational and practical aspects of Electromagnetic sounding of the Earth by different techniques at global, regional and local scales. Moreover, it contains new developments such as the concept of self-consistent tasks of geophysics and , 3-D interpretation of the TEM sounding which, so far, have not all been covered by one book. Electromagnetic Sounding of the Earth's Interior 2nd edition consists of three parts: I- EM sounding methods, II- Forward modelling and inversion techniques, and III - Data processing, analysis, modelling and interpretation. The new edition includes brand new chapters on Pulse and frequency electromagnetic sounding for hydrocarbon offshore exploration. Additionally all other chapters have been extensively updated to include new developments. Presents recently developed methodological findings of the earth's study, including seism...

  13. 21 CFR 876.4590 - Interlocking urethral sound.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Interlocking urethral sound. 876.4590 Section 876...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4590 Interlocking urethral sound. (a) Identification. An interlocking urethral sound is a device that consists of two metal sounds...

  14. Poetry Pages. Sound Effects.

    Science.gov (United States)

    Fina, Allan de

    1992-01-01

    Explains how elementary teachers can help students understand onomatopoeia, suggesting that they define onomatopoeia, share examples of it, read poems and have students discuss onomatopoeic words, act out common household sounds, write about sound effects, and create choral readings of onomatopoeic poems. Two appropriate poems are included. (SM)

  15. Mobile sound: media art in hybrid spaces

    OpenAIRE

    Behrendt, Frauke

    2010-01-01

    The thesis explores the relationships between sound and mobility through an examination\\ud of sound art. The research engages with the intersection of sound, mobility and\\ud art through original empirical work and theoretically through a critical engagement with\\ud sound studies. In dialogue with the work of De Certeau, Lefebvre, Huhtamo and Habermas\\ud in terms of the poetics of walking, rhythms, media archeology and questions of\\ud publicness, I understand sound art as an experimental mobil...

  16. Thermoacoustic focusing lens by symmetric Airy beams with phase manipulations

    Science.gov (United States)

    Liu, Chen; Xia, Jian-Ping; Sun, Hong-Xiang; Yuan, Shou-Qi

    2017-12-01

    We report the realization of broadband acoustic focusing lenses based on two symmetric thermoacoustic phased arrays of Airy beams, in which the units of thermoacoustic phase control are designed by employing air with different temperatures surrounded by rigid insulated boundaries and thermal insulation films. The phase delays of the transmitted and reflected units could cover a whole 2π interval, which arises from the change of the sound velocity of air induced by the variation of the temperature. Based on the units of phase control, we design the transmitted and reflected acoustic focusing lenses with two symmetric Airy beams, and verify the high self-healing focusing characteristic and the feasibility of the thermal insulation films. Besides, the influences of the bending angle of the Airy beam on the focusing performance are discussed in detail. The proposed acoustic lens has advantages of broad bandwidth (about 4.8 kHz), high focusing performance, self-healing feature, and simple structure, which enable it to provide more schemes for acoustic focusing. It has excellent potential applications in acoustic devices.

  17. Coherent beam-beam effects

    International Nuclear Information System (INIS)

    Chao, A.W.

    1992-01-01

    There are two physical pictures that describe the beam-beam interaction in a storage ring collider: The weak-strong and the strong-strong pictures. Both pictures play a role in determining the beam-beam behavior. This review addresses only the strong-strong picture. The corresponding beam dynamical effects are referred to as the coherent beam-beam effects. Some basic knowledge of the weak-strong picture is assumed. To be specific, two beams of opposite charges are considered. (orig.)

  18. Sound source measurement by using a passive sound insulation and a statistical approach

    Science.gov (United States)

    Dragonetti, Raffaele; Di Filippo, Sabato; Mercogliano, Francesco; Romano, Rosario A.

    2015-10-01

    This paper describes a measurement technique developed by the authors that allows carrying out acoustic measurements inside noisy environments reducing background noise effects. The proposed method is based on the integration of a traditional passive noise insulation system with a statistical approach. The latter is applied to signals picked up by usual sensors (microphones and accelerometers) equipping the passive sound insulation system. The statistical approach allows improving of the sound insulation given only by the passive sound insulation system at low frequency. The developed measurement technique has been validated by means of numerical simulations and measurements carried out inside a real noisy environment. For the case-studies here reported, an average improvement of about 10 dB has been obtained in a frequency range up to about 250 Hz. Considerations on the lower sound pressure level that can be measured by applying the proposed method and the measurement error related to its application are reported as well.

  19. Film sound in preservation and presentation

    NARCIS (Netherlands)

    Campanini, S.

    2014-01-01

    What is the nature of film sound? How does it change through time? How can film sound be conceptually defined? To address these issues, this work assumes the perspective of film preservation and presentation practices, describing the preservation of early sound systems, as well as the presentation

  20. Analyzing the Pattern of L1 Sounds on L2 Sounds Produced by Javanese Students of Stkip PGRI Jombang

    Directory of Open Access Journals (Sweden)

    Daning Hentasmaka

    2015-07-01

    Full Text Available The studyconcerns on an analysis on the tendency of first language (L1 sound patterning on second language (L2 sounds done by Javanese students.Focusing on the consonant sounds, the data were collected by recording students’ pronunciationof English words during the pronunciation test. The data then analysed through three activities: data reduction, data display, and conclusion drawing/ verification. Theresult showedthatthe patterning of L1 sounds happened on L2 sounds especially on eleven consonant sounds: the fricatives [v, θ, ð, ʃ, ʒ], the voiceless stops [p, t, k], and the voiced stops [b, d, g].Thosepatterning case emergedmostlyduetothe difference in the existence of consonant sounds and rules of consonant distribution. Besides, one of the cases was caused by the difference in consonant clusters between L1 and L2

  1. ANALYZING THE PATTERN OF L1 SOUNDS ON L2 SOUNDS PRODUCED BY JAVANESE STUDENTS OF STKIP PGRI JOMBANG

    Directory of Open Access Journals (Sweden)

    Daning Hentasmaka

    2015-07-01

    Full Text Available The studyconcerns on an analysis on the tendency of first language (L1 sound patterning on second language (L2 sounds done by Javanese students.Focusing on the consonant sounds, the data were collected by recording students’ pronunciationof English words during the pronunciation test. The data then analysed through three activities: data reduction, data display, and conclusion drawing/ verification. Theresult showedthatthe patterning of L1 sounds happened on L2 sounds especially on eleven consonant sounds: the fricatives [v, θ, ð, ʃ, ʒ], the voiceless stops [p, t, k], and the voiced stops [b, d, g].Thosepatterning case emergedmostlyduetothe difference in the existence of consonant sounds and rules of consonant distribution. Besides, one of the cases was caused by the difference in consonant clusters between L1 and L2.

  2. Opponent Coding of Sound Location (Azimuth) in Planum Temporale is Robust to Sound-Level Variations.

    Science.gov (United States)

    Derey, Kiki; Valente, Giancarlo; de Gelder, Beatrice; Formisano, Elia

    2016-01-01

    Coding of sound location in auditory cortex (AC) is only partially understood. Recent electrophysiological research suggests that neurons in mammalian auditory cortex are characterized by broad spatial tuning and a preference for the contralateral hemifield, that is, a nonuniform sampling of sound azimuth. Additionally, spatial selectivity decreases with increasing sound intensity. To accommodate these findings, it has been proposed that sound location is encoded by the integrated activity of neuronal populations with opposite hemifield tuning ("opponent channel model"). In this study, we investigated the validity of such a model in human AC with functional magnetic resonance imaging (fMRI) and a phase-encoding paradigm employing binaural stimuli recorded individually for each participant. In all subjects, we observed preferential fMRI responses to contralateral azimuth positions. Additionally, in most AC locations, spatial tuning was broad and not level invariant. We derived an opponent channel model of the fMRI responses by subtracting the activity of contralaterally tuned regions in bilateral planum temporale. This resulted in accurate decoding of sound azimuth location, which was unaffected by changes in sound level. Our data thus support opponent channel coding as a neural mechanism for representing acoustic azimuth in human AC. © The Author 2015. Published by Oxford University Press.

  3. Archive of bathymetry data collected in South Florida from 1995 to 2015

    Science.gov (United States)

    Hansen, Mark Erik; DeWitt, Nancy T.; Reynolds, Billy J.

    2017-08-10

    DescriptionLand development and alterations of the ecosystem in south Florida over the past 100 years have decreased freshwater and increased nutrient flows into many of Florida's estuaries, bays, and coastal regions. As a result, there has been a decrease in the water quality in many of these critical habitats, often prompting seagrass die-offs and reduced fish and aquatic life populations. Restoration of water quality in many of these habitats will depend partly upon using numerical-circulation and sediment-transport models to establish water-quality targets and to assess progress toward reaching restoration targets. Application of these models is often complicated because of complex sea floor topography and tidal flow regimes. Consequently, accurate and modern sea-floor or bathymetry maps are critical for numerical modeling research. Modern bathymetry data sets will also permit a comparison to historical data in order to help assess sea-floor changes within these critical habitats. New and detailed data sets also support marine biology studies to help understand migratory and feeding habitats of marine life.This data series is a compilation of 13 mapping projects conducted in south Florida between 1995 and 2015 and archives more than 45 million bathymetric soundings. Data were collected primarily with a single beam sound navigation and ranging (sonar) system called SANDS developed by the U.S. Geological Survey (USGS) in 1993. Bathymetry data for the Estero Bay project were supplemented with the National Aeronautics and Space Administration's (NASA) Experimental Advanced Airborne Research Lidar (EAARL) system. Data from eight rivers in southwest Florida were collected with an interferometric swath bathymetry system. The projects represented in this data series were funded by the USGS Coastal and Marine Geology Program (CMGP), the USGS South Florida Ecosystem Restoration Project- formally named Placed Based Studies, and other non-Federal agencies. The purpose of

  4. Breaking the Sound Barrier

    Science.gov (United States)

    Brown, Tom; Boehringer, Kim

    2007-01-01

    Students in a fourth-grade class participated in a series of dynamic sound learning centers followed by a dramatic capstone event--an exploration of the amazing Trashcan Whoosh Waves. It's a notoriously difficult subject to teach, but this hands-on, exploratory approach ignited student interest in sound, promoted language acquisition, and built…

  5. Sound therapies for tinnitus management.

    Science.gov (United States)

    Jastreboff, Margaret M

    2007-01-01

    Many people with bothersome (suffering) tinnitus notice that their tinnitus changes in different acoustical surroundings, it is more intrusive in silence and less profound in the sound enriched environments. This observation led to the development of treatment methods for tinnitus utilizing sound. Many of these methods are still under investigation in respect to their specific protocol and effectiveness and only some have been objectively evaluated in clinical trials. This chapter will review therapies for tinnitus using sound stimulation.

  6. Structural dynamic response of target container against proton beam

    International Nuclear Information System (INIS)

    Kikuchi, Kenji; Ishikura, Syuichi; Futakawa, Masatoshi; Hino, Ryutaro

    1997-01-01

    Stress waves were analyzed for a target container of neutron science research project using a high-intensity proton accelerator that generates high energy and high current proton beam. In the mercury target, the pulsed proton beam generates intense power density in the course of spallation reaction and causes pressure wave in the mercury and stress wave in the target container due to a sudden temperature change. Structural integrity of the target container depends on the power intensity at a maximum energy deposit. A broad proton profile is favorable to the structural assessment of the container rather than narrow one. Stress wave have propagated in the target container at a speed of sound. It only takes 0.1 ms for the size of 40 cm length stainless steel container. Further assessment is necessary to optimize a geometry of the container and establish a method to evaluate a life time. (author)

  7. Structural dynamic response of target container against proton beam

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Kenji; Ishikura, Syuichi; Futakawa, Masatoshi; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    Stress waves were analyzed for a target container of neutron science research project using a high-intensity proton accelerator that generates high energy and high current proton beam. In the mercury target, the pulsed proton beam generates intense power density in the course of spallation reaction and causes pressure wave in the mercury and stress wave in the target container due to a sudden temperature change. Structural integrity of the target container depends on the power intensity at a maximum energy deposit. A broad proton profile is favorable to the structural assessment of the container rather than narrow one. Stress wave have propagated in the target container at a speed of sound. It only takes 0.1 ms for the size of 40 cm length stainless steel container. Further assessment is necessary to optimize a geometry of the container and establish a method to evaluate a life time. (author)

  8. Effect of Micro-Bubbles in Water on Beam Patterns of Parametric Array

    Science.gov (United States)

    Hashiba, Kunio; Masuzawa, Hiroshi

    2003-05-01

    The improvement in efficiency of a parametric array by nonlinear oscillation of micro-bubbles in water is studied in this paper. The micro-bubble oscillation can increase the nonlinear coefficient of the acoustic medium. The amplitude of the difference-frequency wave along the longitudinal axis and its beam patterns in the field including the layer with micro-bubbles were analyzed using a Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation. As a result, the largest improvement in efficiency was obtained and a narrow parametric beam was formed by forming a layer with micro-bubbles in front of a parametric sound radiator as thick as about the shock formation distance. If the layer becomes significantly thicker than the distance, the beam of the difference-frequency wave in the far-field will become broader. If the layer is significantly thinner than the distance, the intensity level of the wave in the far-field will be too low.

  9. Numerical Model on Sound-Solid Coupling in Human Ear and Study on Sound Pressure of Tympanic Membrane

    Directory of Open Access Journals (Sweden)

    Yao Wen-juan

    2011-01-01

    Full Text Available Establishment of three-dimensional finite-element model of the whole auditory system includes external ear, middle ear, and inner ear. The sound-solid-liquid coupling frequency response analysis of the model was carried out. The correctness of the FE model was verified by comparing the vibration modes of tympanic membrane and stapes footplate with the experimental data. According to calculation results of the model, we make use of the least squares method to fit out the distribution of sound pressure of external auditory canal and obtain the sound pressure function on the tympanic membrane which varies with frequency. Using the sound pressure function, the pressure distribution on the tympanic membrane can be directly derived from the sound pressure at the external auditory canal opening. The sound pressure function can make the boundary conditions of the middle ear structure more accurate in the mechanical research and improve the previous boundary treatment which only applied uniform pressure acting to the tympanic membrane.

  10. Sounds in one-dimensional superfluid helium

    International Nuclear Information System (INIS)

    Um, C.I.; Kahng, W.H.; Whang, E.H.; Hong, S.K.; Oh, H.G.; George, T.F.

    1989-01-01

    The temperature variations of first-, second-, and third-sound velocity and attenuation coefficients in one-dimensional superfluid helium are evaluated explicitly for very low temperatures and frequencies (ω/sub s/tau 2 , and the ratio of second sound to first sound becomes unity as the temperature decreases to absolute zero

  11. Conditioned sounds enhance visual processing.

    Directory of Open Access Journals (Sweden)

    Fabrizio Leo

    Full Text Available This psychophysics study investigated whether prior auditory conditioning influences how a sound interacts with visual perception. In the conditioning phase, subjects were presented with three pure tones ( =  conditioned stimuli, CS that were paired with positive, negative or neutral unconditioned stimuli. As unconditioned reinforcers we employed pictures (highly pleasant, unpleasant and neutral or monetary outcomes (+50 euro cents, -50 cents, 0 cents. In the subsequent visual selective attention paradigm, subjects were presented with near-threshold Gabors displayed in their left or right hemifield. Critically, the Gabors were presented in synchrony with one of the conditioned sounds. Subjects discriminated whether the Gabors were presented in their left or right hemifields. Participants determined the location more accurately when the Gabors were presented in synchrony with positive relative to neutral sounds irrespective of reinforcer type. Thus, previously rewarded relative to neutral sounds increased the bottom-up salience of the visual Gabors. Our results are the first demonstration that prior auditory conditioning is a potent mechanism to modulate the effect of sounds on visual perception.

  12. Robust segmentation and retrieval of environmental sounds

    Science.gov (United States)

    Wichern, Gordon

    The proliferation of mobile computing has provided much of the world with the ability to record any sound of interest, or possibly every sound heard in a lifetime. The technology to continuously record the auditory world has applications in surveillance, biological monitoring of non-human animal sounds, and urban planning. Unfortunately, the ability to record anything has led to an audio data deluge, where there are more recordings than time to listen. Thus, access to these archives depends on efficient techniques for segmentation (determining where sound events begin and end), indexing (storing sufficient information with each event to distinguish it from other events), and retrieval (searching for and finding desired events). While many such techniques have been developed for speech and music sounds, the environmental and natural sounds that compose the majority of our aural world are often overlooked. The process of analyzing audio signals typically begins with the process of acoustic feature extraction where a frame of raw audio (e.g., 50 milliseconds) is converted into a feature vector summarizing the audio content. In this dissertation, a dynamic Bayesian network (DBN) is used to monitor changes in acoustic features in order to determine the segmentation of continuously recorded audio signals. Experiments demonstrate effective segmentation performance on test sets of environmental sounds recorded in both indoor and outdoor environments. Once segmented, every sound event is indexed with a probabilistic model, summarizing the evolution of acoustic features over the course of the event. Indexed sound events are then retrieved from the database using different query modalities. Two important query types are sound queries (query-by-example) and semantic queries (query-by-text). By treating each sound event and semantic concept in the database as a node in an undirected graph, a hybrid (content/semantic) network structure is developed. This hybrid network can

  13. Accelerators and Beams, multimedia computer-based training in accelerator physics

    International Nuclear Information System (INIS)

    Silbar, R.R.; Browman, A.A.; Mead, W.C.; Williams, R.A.

    1999-01-01

    We are developing a set of computer-based tutorials on accelerators and charged-particle beams under an SBIR grant from the DOE. These self-paced, interactive tutorials, available for Macintosh and Windows platforms, use multimedia techniques to enhance the user close-quote s rate of learning and length of retention of the material. They integrate interactive On-Screen Laboratories, hypertext, line drawings, photographs, two- and three-dimensional animations, video, and sound. They target a broad audience, from undergraduates or technicians to professionals. Presently, three modules have been published (Vectors, Forces, and Motion), a fourth (Dipole Magnets) has been submitted for review, and three more exist in prototype form (Quadrupoles, Matrix Transport, and Properties of Charged-Particle Beams). Participants in the poster session will have the opportunity to try out these modules on a laptop computer. copyright 1999 American Institute of Physics

  14. Sound-Symbolism Boosts Novel Word Learning

    Science.gov (United States)

    Lockwood, Gwilym; Dingemanse, Mark; Hagoort, Peter

    2016-01-01

    The existence of sound-symbolism (or a non-arbitrary link between form and meaning) is well-attested. However, sound-symbolism has mostly been investigated with nonwords in forced choice tasks, neither of which are representative of natural language. This study uses ideophones, which are naturally occurring sound-symbolic words that depict sensory…

  15. Second sound tracking system

    Science.gov (United States)

    Yang, Jihee; Ihas, Gary G.; Ekdahl, Dan

    2017-10-01

    It is common that a physical system resonates at a particular frequency, whose frequency depends on physical parameters which may change in time. Often, one would like to automatically track this signal as the frequency changes, measuring, for example, its amplitude. In scientific research, one would also like to utilize the standard methods, such as lock-in amplifiers, to improve the signal to noise ratio. We present a complete He ii second sound system that uses positive feedback to generate a sinusoidal signal of constant amplitude via automatic gain control. This signal is used to produce temperature/entropy waves (second sound) in superfluid helium-4 (He ii). A lock-in amplifier limits the oscillation to a desirable frequency and demodulates the received sound signal. Using this tracking system, a second sound signal probed turbulent decay in He ii. We present results showing that the tracking system is more reliable than those of a conventional fixed frequency method; there is less correlation with temperature (frequency) fluctuation when the tracking system is used.

  16. Archive of side scan sonar and swath bathymetry data collected during USGS cruise 10CCT01 offshore of Cat Island, Gulf Islands National Seashore, Mississippi, March 2010

    Science.gov (United States)

    DeWitt, Nancy T.; Flocks, James G.; Pfeiffer, William R.; Wiese, Dana S.

    2010-01-01

    In March of 2010, the U.S. Geological Survey (USGS) conducted geophysical surveys east of Cat Island, Mississippi (fig. 1). The efforts were part of the USGS Gulf of Mexico Science Coordination partnership with the U.S. Army Corps of Engineers (USACE) to assist the Mississippi Coastal Improvements Program (MsCIP) and the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazards Susceptibility Project by mapping the shallow geological stratigraphic framework of the Mississippi Barrier Island Complex. These geophysical surveys will provide the data necessary for scientists to define, interpret, and provide baseline bathymetry and seafloor habitat for this area and to aid scientists in predicting future geomorpholocial changes of the islands with respect to climate change, storm impact, and sea-level rise. Furthermore, these data will provide information for barrier island restoration, particularly in Camille Cut, and provide protection for the historical Fort Massachusetts. For more information refer to http://ngom.usgs.gov/gomsc/mscip/index.html. This report serves as an archive of the processed swath bathymetry and side scan sonar data (SSS). Data products herein include gridded and interpolated surfaces, surface images, and x,y,z data products for both swath bathymetry and side scan sonar imagery. Additional files include trackline maps, navigation files, GIS files, Field Activity Collection System (FACS) logs, and formal FGDC metadata. Scanned images of the handwritten FACS logs and digital FACS logs are also provided as PDF files. Refer to the Acronyms page for expansion of acronyms and abbreviations used in this report or hold the cursor over an acronym for a pop-up explanation. The USGS St. Petersburg Coastal and Marine Science Center assigns a unique identifier to each cruise or field activity. For example, 10CCT01 tells us the data were collected in 2010 for the Coastal Change and Transport (CCT) study and the data were collected during the first field

  17. Underwater Sound Propagation from Marine Pile Driving.

    Science.gov (United States)

    Reyff, James A

    2016-01-01

    Pile driving occurs in a variety of nearshore environments that typically have very shallow-water depths. The propagation of pile-driving sound in water is complex, where sound is directly radiated from the pile as well as through the ground substrate. Piles driven in the ground near water bodies can produce considerable underwater sound energy. This paper presents examples of sound propagation through shallow-water environments. Some of these examples illustrate the substantial variation in sound amplitude over time that can be critical to understand when computing an acoustic-based safety zone for aquatic species.

  18. CRED Gridded Bathymetry of the 1955 Eruption Site and Seamount (100-022) in the Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-022b is a 60-m ASCII grid of depth data collected near 1955 Eruption Site multibeam bathymetry data from a SeaBeam 210 sonar aboard the R/V...

  19. Okeanos Explorer (EX1607): CAPSTONE Wake Island PRI MNM (Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include 24 hour/day mapping operations using the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries...

  20. Sound topology, duality, coherence and wave-mixing an introduction to the emerging new science of sound

    CERN Document Server

    Deymier, Pierre

    2017-01-01

    This book offers an essential introduction to the notions of sound wave topology, duality, coherence and wave-mixing, which constitute the emerging new science of sound. It includes general principles and specific examples that illuminate new non-conventional forms of sound (sound topology), unconventional quantum-like behavior of phonons (duality), radical linear and nonlinear phenomena associated with loss and its control (coherence), and exquisite effects that emerge from the interaction of sound with other physical and biological waves (wave mixing).  The book provides the reader with the foundations needed to master these complex notions through simple yet meaningful examples. General principles for unraveling and describing the topology of acoustic wave functions in the space of their Eigen values are presented. These principles are then applied to uncover intrinsic and extrinsic approaches to achieving non-conventional topologies by breaking the time revers al symmetry of acoustic waves. Symmetry brea...

  1. Diffuse sound field: challenges and misconceptions

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2016-01-01

    Diffuse sound field is a popular, yet widely misused concept. Although its definition is relatively well established, acousticians use this term for different meanings. The diffuse sound field is defined by a uniform sound pressure distribution (spatial diffusion or homogeneity) and uniform...... tremendously in different chambers because the chambers are non-diffuse in variously different ways. Therefore, good objective measures that can quantify the degree of diffusion and potentially indicate how to fix such problems in reverberation chambers are needed. Acousticians often blend the concept...... of mixing and diffuse sound field. Acousticians often refer diffuse reflections from surfaces to diffuseness in rooms, and vice versa. Subjective aspects of diffuseness have not been much investigated. Finally, ways to realize a diffuse sound field in a finite space are discussed....

  2. Side-Scan Sonar Image Mosaic Using Couple Feature Points with Constraint of Track Line Positions

    Directory of Open Access Journals (Sweden)

    Jianhu Zhao

    2018-06-01

    Full Text Available To obtain large-scale seabed surface image, this paper proposes a side-scan sonar (SSS image mosaic method using couple feature points (CFPs with constraint of track line positions. The SSS geocoded images are firstly used to form a coarsely mosaicked one and the overlapping areas between adjacent strip images can be determined based on geographic information. Inside the overlapping areas, the feature point (FP detection and registration operation are adopted for both strips. According to the detected CFPs and track line positions, an adjustment model is established to accommodate complex local distortions as well as ensure the global stability. This proposed method effectively solves the problem of target ghosting or dislocation and no accumulated errors arise in the mosaicking process. Experimental results show that the finally mosaicked image correctly reflects the object distribution, which is meaningful for understanding and interpreting seabed topography.

  3. New sidescan sonar and gravity evidence that the Nova-Canton Trough is a fracture zone

    Science.gov (United States)

    Joseph, Devorah; Taylor, Brian; Shor, Alexander N.

    1992-05-01

    A 1990 sidescan sonar survey in the eastern region of the Nova-Canton Trough mapped 138°-striking abyssal-hill fabric trending into 70°-striking trough structures. The location and angle of intersection of the abyssal hills with the eastern Nova-Canton Trough effectively disprove a spreading-center origin of this feature. Free-air gravity anomalies derived from satellite altimetry data show continuity, across the Line Islands, of the Nova-Canton Trough with the Clipperton Fracture Zone. The Canton-Clipperton trend is copolar, about a pole at 30°S, 152°W, with other coeval Pacific-Farallon fracture-zone segments, from the Pau to Marquesas fracture zones. This copolarity leads us to postulate a Pacific-Farallon spreading pattern for the magnetic quiet zone region north and east of the Manihiki Plateau, with the Nova-Canton Trough originating as a transform fault in this system.

  4. WODA Technical Guidance on Underwater Sound from Dredging.

    Science.gov (United States)

    Thomsen, Frank; Borsani, Fabrizio; Clarke, Douglas; de Jong, Christ; de Wit, Pim; Goethals, Fredrik; Holtkamp, Martine; Martin, Elena San; Spadaro, Philip; van Raalte, Gerard; Victor, George Yesu Vedha; Jensen, Anders

    2016-01-01

    The World Organization of Dredging Associations (WODA) has identified underwater sound as an environmental issue that needs further consideration. A WODA Expert Group on Underwater Sound (WEGUS) prepared a guidance paper in 2013 on dredging sound, including a summary of potential impacts on aquatic biota and advice on underwater sound monitoring procedures. The paper follows a risk-based approach and provides guidance for standardization of acoustic terminology and methods for data collection and analysis. Furthermore, the literature on dredging-related sounds and the effects of dredging sounds on marine life is surveyed and guidance on the management of dredging-related sound risks is provided.

  5. Detecting change in stochastic sound sequences.

    Directory of Open Access Journals (Sweden)

    Benjamin Skerritt-Davis

    2018-05-01

    Full Text Available Our ability to parse our acoustic environment relies on the brain's capacity to extract statistical regularities from surrounding sounds. Previous work in regularity extraction has predominantly focused on the brain's sensitivity to predictable patterns in sound sequences. However, natural sound environments are rarely completely predictable, often containing some level of randomness, yet the brain is able to effectively interpret its surroundings by extracting useful information from stochastic sounds. It has been previously shown that the brain is sensitive to the marginal lower-order statistics of sound sequences (i.e., mean and variance. In this work, we investigate the brain's sensitivity to higher-order statistics describing temporal dependencies between sound events through a series of change detection experiments, where listeners are asked to detect changes in randomness in the pitch of tone sequences. Behavioral data indicate listeners collect statistical estimates to process incoming sounds, and a perceptual model based on Bayesian inference shows a capacity in the brain to track higher-order statistics. Further analysis of individual subjects' behavior indicates an important role of perceptual constraints in listeners' ability to track these sensory statistics with high fidelity. In addition, the inference model facilitates analysis of neural electroencephalography (EEG responses, anchoring the analysis relative to the statistics of each stochastic stimulus. This reveals both a deviance response and a change-related disruption in phase of the stimulus-locked response that follow the higher-order statistics. These results shed light on the brain's ability to process stochastic sound sequences.

  6. Directional sound radiation from substation transformers

    International Nuclear Information System (INIS)

    Maybee, N.

    2009-01-01

    This paper presented the results of a study in which acoustical measurements at two substations were analyzed to investigate the directional behaviour of typical arrays having 2 or 3 transformers. Substation transformers produce a characteristic humming sound that is caused primarily by vibration of the core at twice the frequency of the power supply. The humming noise radiates predominantly from the tank enclosing the core. The main components of the sound are harmonics of 120 Hz. Sound pressure level data were obtained for various directions and distances from the arrays, ranging from 0.5 m to over 100 m. The measured sound pressure levels of the transformer tones displayed substantial positive and negative excursions from the calculated average values for many distances and directions. The results support the concept that the directional effects are associated with constructive and destructive interference of tonal sound waves emanating from different parts of the array. Significant variations in the directional sound pattern can occur in the near field of a single transformer or an array, and the extent of the near field is significantly larger than the scale of the array. Based on typical dimensions for substation sites, the distance to the far field may be much beyond the substation boundary and beyond typical setbacks to the closest dwellings. As such, the directional sound radiation produced by transformer arrays introduces additional uncertainty in the prediction of substation sound levels at dwellings within a few hundred meters of a substation site. 4 refs., 4 figs.

  7. Underwater Gliders by Dr. Kevin Smith [video

    OpenAIRE

    Naval Postgraduate School Physics

    2015-01-01

    NPS Physics NPS Physics Research Projects Underwater glider research is currently underway in the physics department at the naval postgraduate in Monterey Ca. Dr. Kevin Smith is a specialist in underwater acoustics and sonar systems. He and his team are currently focused on autonomous underwater gliders and developing systems capable of detecting parameters in the ocean and listening for various sources of sound.

  8. On the sound absorption coefficient of porous asphalt pavements for oblique incident sound waves

    NARCIS (Netherlands)

    Bezemer-Krijnen, Marieke; Wijnant, Ysbrand H.; de Boer, Andries; Bekke, Dirk; Davy, J.; Don, Ch.; McMinn, T.; Dowsett, L.; Broner, N.; Burgess, M.

    2014-01-01

    A rolling tyre will radiate noise in all directions. However, conventional measurement techniques for the sound absorption of surfaces only give the absorption coefficient for normal incidence. In this paper, a measurement technique is described with which it is possible to perform in situ sound

  9. Neuroplasticity beyond sounds

    DEFF Research Database (Denmark)

    Reybrouck, Mark; Brattico, Elvira

    2015-01-01

    Capitalizing from neuroscience knowledge on how individuals are affected by the sound environment, we propose to adopt a cybernetic and ecological point of view on the musical aesthetic experience, which includes subprocesses, such as feature extraction and integration, early affective reactions...... and motor actions, style mastering and conceptualization, emotion and proprioception, evaluation and preference. In this perspective, the role of the listener/composer/performer is seen as that of an active "agent" coping in highly individual ways with the sounds. The findings concerning the neural...

  10. Underwater Cylindrical Object Detection Using the Spectral Features of Active Sonar Signals with Logistic Regression Models

    Directory of Open Access Journals (Sweden)

    Yoojeong Seo

    2018-01-01

    Full Text Available The issue of detecting objects bottoming on the sea floor is significant in various fields including civilian and military areas. The objective of this study is to investigate the logistic regression model to discriminate the target from the clutter and to verify the possibility of applying the model trained by the simulated data generated by the mathematical model to the real experimental data because it is not easy to obtain sufficient data in the underwater field. In the first stage of this study, when the clutter signal energy is so strong that the detection of a target is difficult, the logistic regression model is employed to distinguish the strong clutter signal and the target signal. Previous studies have found that if the clutter energy is larger, false detection occurs even for the various existing detection schemes. For this reason, the discrete Fourier transform (DFT magnitude spectrum of acoustic signals received by active sonar is applied to train the model to distinguish whether the received signal contains a target signal or not. The goodness of fit of the model is verified in terms of receiver operation characteristic (ROC, area under ROC curve (AUC, and classification table. The detection performance of the proposed model is evaluated in terms of detection rate according to target to clutter ratio (TCR. Furthermore, the real experimental data are employed to test the proposed approach. When using the experimental data to test the model, the logistic regression model is trained by the simulated data that are generated based on the mathematical model for the backscattering of the cylindrical object. The mathematical model is developed according to the size of the cylinder used in the experiment. Since the information on the experimental environment including the sound speed, the sediment type and such is not available, once simulated data are generated under various conditions, valid simulated data are selected using 70% of the

  11. Statistics of natural binaural sounds.

    Directory of Open Access Journals (Sweden)

    Wiktor Młynarski

    Full Text Available Binaural sound localization is usually considered a discrimination task, where interaural phase (IPD and level (ILD disparities at narrowly tuned frequency channels are utilized to identify a position of a sound source. In natural conditions however, binaural circuits are exposed to a stimulation by sound waves originating from multiple, often moving and overlapping sources. Therefore statistics of binaural cues depend on acoustic properties and the spatial configuration of the environment. Distribution of cues encountered naturally and their dependence on physical properties of an auditory scene have not been studied before. In the present work we analyzed statistics of naturally encountered binaural sounds. We performed binaural recordings of three auditory scenes with varying spatial configuration and analyzed empirical cue distributions from each scene. We have found that certain properties such as the spread of IPD distributions as well as an overall shape of ILD distributions do not vary strongly between different auditory scenes. Moreover, we found that ILD distributions vary much weaker across frequency channels and IPDs often attain much higher values, than can be predicted from head filtering properties. In order to understand the complexity of the binaural hearing task in the natural environment, sound waveforms were analyzed by performing Independent Component Analysis (ICA. Properties of learned basis functions indicate that in natural conditions soundwaves in each ear are predominantly generated by independent sources. This implies that the real-world sound localization must rely on mechanisms more complex than a mere cue extraction.

  12. Statistics of natural binaural sounds.

    Science.gov (United States)

    Młynarski, Wiktor; Jost, Jürgen

    2014-01-01

    Binaural sound localization is usually considered a discrimination task, where interaural phase (IPD) and level (ILD) disparities at narrowly tuned frequency channels are utilized to identify a position of a sound source. In natural conditions however, binaural circuits are exposed to a stimulation by sound waves originating from multiple, often moving and overlapping sources. Therefore statistics of binaural cues depend on acoustic properties and the spatial configuration of the environment. Distribution of cues encountered naturally and their dependence on physical properties of an auditory scene have not been studied before. In the present work we analyzed statistics of naturally encountered binaural sounds. We performed binaural recordings of three auditory scenes with varying spatial configuration and analyzed empirical cue distributions from each scene. We have found that certain properties such as the spread of IPD distributions as well as an overall shape of ILD distributions do not vary strongly between different auditory scenes. Moreover, we found that ILD distributions vary much weaker across frequency channels and IPDs often attain much higher values, than can be predicted from head filtering properties. In order to understand the complexity of the binaural hearing task in the natural environment, sound waveforms were analyzed by performing Independent Component Analysis (ICA). Properties of learned basis functions indicate that in natural conditions soundwaves in each ear are predominantly generated by independent sources. This implies that the real-world sound localization must rely on mechanisms more complex than a mere cue extraction.

  13. Moth hearing and sound communication

    DEFF Research Database (Denmark)

    Nakano, Ryo; Takanashi, Takuma; Surlykke, Annemarie

    2015-01-01

    Active echolocation enables bats to orient and hunt the night sky for insects. As a counter-measure against the severe predation pressure many nocturnal insects have evolved ears sensitive to ultrasonic bat calls. In moths bat-detection was the principal purpose of hearing, as evidenced by compar......Active echolocation enables bats to orient and hunt the night sky for insects. As a counter-measure against the severe predation pressure many nocturnal insects have evolved ears sensitive to ultrasonic bat calls. In moths bat-detection was the principal purpose of hearing, as evidenced...... by comparable hearing physiology with best sensitivity in the bat echolocation range, 20–60 kHz, across moths in spite of diverse ear morphology. Some eared moths subsequently developed sound-producing organs to warn/startle/jam attacking bats and/or to communicate intraspecifically with sound. Not only...... the sounds for interaction with bats, but also mating signals are within the frequency range where bats echolocate, indicating that sound communication developed after hearing by “sensory exploitation”. Recent findings on moth sound communication reveal that close-range (~ a few cm) communication with low...

  14. Cylindrical target Li-beam-driven hohlraum experiments

    International Nuclear Information System (INIS)

    Derzon, M.S.; Aubert, J.; Chandler, G.A.

    1998-06-01

    The authors performed a series of experiments on the Particle Beam Fusion Accelerator II (PBFA II) in May, 1994, and obtained a brightness temperature of 61 ± 2 eV for an ion-beam heated hohlraum. The hohlraum was a 4-mm-diameter, right-circular cylinder with a 1.5-mm-thick gold wall, a low-density CH foam fill, and a 1.5- or 3-mm-diameter diagnostic aperture in the top. The nominal parameters of the radially-incident PBFA II Li ion beam were 9 MeV peak energy (∼10 MeV at the gas cell) at the target at a peak power of 2.5 ± 0.3 TW/cm 2 and a 15 ns pulse width. Azimuthal variations in intensity of a factor of 3, with respect to the mean, were observed. Nonuniformities in thermal x-ray emission across the area of the diagnostic hole were also observed. Time-dependent hole-closure velocities were measured: the time-averaged velocity of ∼2 cm/micros is in good agreement with sound speed estimates. Unfolded x-ray spectra and brightness temperatures as a function of time are reported and compared to simulations. Hole closure corrections are discussed with comparisons between XRD and bolometer measurements. Temperature scaling with power on target is also presented

  15. Seabed habitat mapping employing single and multi-beam backscatter data: A case study from the western continental shelf of India

    Digital Repository Service at National Institute of Oceanography (India)

    Haris, K.; Chakraborty, B.; Ingole, B.S.; Menezes, A.A.A.; Srivastava, R.

    Hz MBES data were acquired using the EM1002 echo-sounding system installed onboard RV “Sagar Sukti” in April 2007. The Simrad EM1002 is a phase interpolated beam-forming MBES with 128 transducer elements forming 111 beams in a semicircular array of 45... cm radius. This echo-sounder was calibrated following a “patch test” to minimize navigational and motion errors as described in the Simrad EM1002 installation manual. The line spacing was around three to four times water depth to provide sufficient...

  16. Simulation of sound waves using the Lattice Boltzmann Method for fluid flow: Benchmark cases for outdoor sound propagation

    NARCIS (Netherlands)

    Salomons, E.M.; Lohman, W.J.A.; Zhou, H.

    2016-01-01

    Propagation of sound waves in air can be considered as a special case of fluid dynamics. Consequently, the lattice Boltzmann method (LBM) for fluid flow can be used for simulating sound propagation. In this article application of the LBM to sound propagation is illustrated for various cases:

  17. Beacons of Sound

    DEFF Research Database (Denmark)

    Knakkergaard, Martin

    2018-01-01

    The chapter discusses expectations and imaginations vis-à-vis the concert hall of the twenty-first century. It outlines some of the central historical implications of western culture’s haven for sounding music. Based on the author’s study of the Icelandic concert-house Harpa, the chapter considers...... how these implications, together with the prime mover’s visions, have been transformed as private investors and politicians took over. The chapter furthermore investigates the objectives regarding musical sound and the far-reaching demands concerning acoustics that modern concert halls are required...

  18. Sound & The Senses

    DEFF Research Database (Denmark)

    Schulze, Holger

    2012-01-01

    How are those sounds you hear right now technically generated and post-produced, how are they aesthetically conceptualized and how culturally dependant are they really? How is your ability to hear intertwined with all the other senses and their cultural, biographical and technological constructio...... over time? And how is listening and sounding a deeply social activity – constructing our way of living together in cities as well as in apartment houses? A radio feature with Jonathan Sterne, AGF a.k.a Antye Greie, Jens Gerrit Papenburg & Holger Schulze....

  19. CRED Gridded Bathymetry of Nihoa Island and transit to Kauai (100-026) in the Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-026b is a 60-m ASCII grid of depth data collected near Nihoa multibeam bathymetry data from a SeaBeam 210 sonar aboard the R/V Kai'imikai-O-Kanaloa...

  20. CRED Gridded Bathymetry of St. Rogatien and Brooks Banks (100-018) in the Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-018b is a 60-m ASCII grid of depth data collected near St. Rogatien multibeam bathymetry data from a SeaBeam 210 sonar aboard the R/V Kai'imikai-O-Kanaloa...