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Title: COMPARATIVE MORPHOLOGY OF SOUND PRODUCING MECHANISMS IN TWO SPECIES OF OPHIDIID FISHES.
Creator: RITTGERS, NANCY GOLDCAMP., Florida Atlantic University
Abstract/Description: The sound producing mechanisms of Chilara taylori (Girard) and Ophidion grayi (Fowler) are sexually dimorphic. These mechanisms involve the airbladder, a modified anterior axial skeleton and three pairs of muscles; all have an enlarged first vertebra and a pair of similarly modified and enlarged first ribs. In the male Chilara taylori, two thin convex bones are embedded in the anterior face of the airbladder. Slits are present in the lateral wall of the airbladder just behind the embedded...
Show moreThe sound producing mechanisms of Chilara taylori (Girard) and Ophidion grayi (Fowler) are sexually dimorphic. These mechanisms involve the airbladder, a modified anterior axial skeleton and three pairs of muscles; all have an enlarged first vertebra and a pair of similarly modified and enlarged first ribs. In the male Chilara taylori, two thin convex bones are embedded in the anterior face of the airbladder. Slits are present in the lateral wall of the airbladder just behind the embedded bones. The male Ophidion grayi has a very rigid airbladder. Highly modified third ribs shaped like inverted ram's horns are embedded in the airbladder wall. These ribs encircle a membranous area in the anterior of the airbladder in which a median rocker bone is embedded. The sound producing mechanisms of the females of both species lack specialized bones associated with the airbladder. Their sound producing mechanisms are not as well developed as in the male.
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Date Issued: 1980
PURL: http://purl.flvc.org/fcla/dt/14020
Subject Headings: Fish sounds
Format: Document (PDF)

$Measurements of transmission fluctuations at three ranges for refracted paths through the deep ocean$

Title: Measurements of transmission fluctuations at three ranges for refracted paths through the deep ocean.
Creator: DeFerrari, H. A., Davis, R. I., Nguyen, H., Tusting, Robert F., Williams, N. J., Harbor Branch Oceanographic Institute
Date Issued: 1983
PURL: http://purl.flvc.org/fau/fd/FA00007174
Subject Headings: Acoustics, Sound, Underwater acoustics, Sound--Speed, Sound--Transmission
Format: Document (PDF)

Title: Sparse representation classification of dolphin whistles using local binary patterns.
Creator: Esfahanian, Mahdi, Zhuang, Hanqi, Erdol, Nurgun, Graduate College
Date Issued: 2013-04-12
PURL: http://purl.flvc.org/fcla/dt/3361295
Subject Headings: Dolphins, Dolphin sounds, Bioacoustics
Format: Document (PDF)

Title: Scattering of sound from a fluid-loaded cylindrical shell with a finite length mass inhomogeneity.
Creator: Lefevre, Thierry Alain., Florida Atlantic University, Cuschieri, Joseph M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The problem investigated in this thesis is that of an infinite, fluid-loaded, elastic cylindrical shell with an inhomogeneity of finite length excited by an acoustic plane wave. Seven inhomogeneities are considered to examine the parameters that influence the scattering. A full numerical approach and an iterative approach are developed to solve the shell and acoustic equations of motion expressed in the wavenumber domain. The response Green's function in the spatial domain is obtained using...
Show moreThe problem investigated in this thesis is that of an infinite, fluid-loaded, elastic cylindrical shell with an inhomogeneity of finite length excited by an acoustic plane wave. Seven inhomogeneities are considered to examine the parameters that influence the scattering. A full numerical approach and an iterative approach are developed to solve the shell and acoustic equations of motion expressed in the wavenumber domain. The response Green's function in the spatial domain is obtained using the hybrid analytical numerical technique, while the far-field scattered pressure is obtained by applying the Stationary Phase approximation. An analytical approach for the special case of a concentrated ring is developed, and the results compared to those from the full numerical solution. The range of applicability of the iterative approach is also investigated. The results show that the scattering pattern is a function of the spectral contents of the inhomogeneity distribution, and that the inhomogeneity mass influenced both the scattering pattern, and the scattering level. From the results it was also noted that an oblique angle of incidence steered the main lobe of the scattering pattern in the direction of the incoming acoustic wave. It is also demonstrated that the concentrated ring is usually a poor model to represent inhomogeneity of finite length.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15385
Subject Headings: Elastic plates and shells, Sound
Format: Document (PDF)

Title: A comparison of shallow water sound propagation measurements and computer model predictions.
Creator: Cichock, Joseph Arnold., Florida Atlantic University, Glegg, Stewart A. L.
Abstract/Description: High-resolution sound propagation measurements were made on a 1/10000 th-scale model of the Santa Lucia Escarpment, located off the Southern California coast. The tank was modified from previous experiments using a rubber coating on the tank bottom. High frequency, high resolution, Transmission Loss measurements were made on the SFTF range, Dania Florida. The Parabolic Equation Model RAM was used to validate these measurement sets. A new approach to account for shear wave effects on the...
Show moreHigh-resolution sound propagation measurements were made on a 1/10000 th-scale model of the Santa Lucia Escarpment, located off the Southern California coast. The tank was modified from previous experiments using a rubber coating on the tank bottom. High frequency, high resolution, Transmission Loss measurements were made on the SFTF range, Dania Florida. The Parabolic Equation Model RAM was used to validate these measurement sets. A new approach to account for shear wave effects on the Transmission Loss for the RAM model was developed. Using this new approach, the scaled low frequency Santa Lucia measurements showed excellent agreement with the RAM calculated TL, but there were discrepancies in the predictions of the high frequency at sea measurements at ranges greater than 1 km.
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Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/12706
Subject Headings: Underwater acoustics, Sound--Transmission
Format: Document (PDF)

Title: MEASUREMENT, ANALYSIS, CLASSIFICATION AND DETECTION OF GUNSHOT AND GUNSHOT-LIKE SOUNDS.
Creator: Baliram, Rajesh Singh, Zhuang, Hanqi, Florida Atlantic University, Department of Computer and Electrical Engineering and Computer Science, College of Engineering and Computer Science
Abstract/Description: The recent uptick in senseless shootings in otherwise quiet and relatively safe environments is powerful evidence of the need, now more than ever, to reduce these occurrences. Artificial intelligence (AI) can play a significant role in deterring individuals from attempting these acts of violence. The installation of audio sensors can assist in the proper surveillance of surroundings linked to public safety, which is the first step toward AI-driven surveillance. With the increasing popularity...
Show moreThe recent uptick in senseless shootings in otherwise quiet and relatively safe environments is powerful evidence of the need, now more than ever, to reduce these occurrences. Artificial intelligence (AI) can play a significant role in deterring individuals from attempting these acts of violence. The installation of audio sensors can assist in the proper surveillance of surroundings linked to public safety, which is the first step toward AI-driven surveillance. With the increasing popularity of machine learning (ML) processes, systems are being developed and optimized to assist personnel in highly dangerous situations. In addition to saving innocent lives, supporting the capture of the responsible criminals is part of the AI algorithm that can be hosted in acoustic gunshot detection systems (AGDSs). Although there has been some speculation that these AGDSs produce a higher false positive rate (FPR) than reported in their specifications, optimizing the dataset used for the model’s training and testing will enhance its performance. This dissertation proposes a new gunshot-like sound database that can be incorporated into a dataset for improved training and testing of a ML gunshot detection model. Reduction of the sample bias (that is, a bias in ML caused by an incomplete database) is achievable. The Mel frequency cepstral coefficient (MFCC) feature extraction process was utilized in this research. The uniform manifold and projection (UMAP) algorithm revealed that the MFCCs of this newly created database were the closest sounds to a gunshot sound, as compared to other gunshot-like sounds reported in literature. The UMAP algorithm reinforced the outcome derived from the calculation of the distances of the centroids of various gunshot-like sounds in MFCCs’ clusters. Further research was conducted into the feature reduction aspect of the gunshot detection ML model. Reducing a feature set to a minimum, while also maintaining a high accuracy rate, is a key parameter of a highly efficient model. Therefore, it is necessary for field deployed ML applications to be computationally light weight and highly efficient. Building on the discoveries of this research can lead to the development of highly efficient gunshot detection models.
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Date Issued: 2022
PURL: http://purl.flvc.org/fau/fd/FA00014110
Subject Headings: Firearms, Sound, Detectors, Machine learning
Format: Document (PDF)

Title: Effects of nature-based sounds on patient anxiety during the preoperative period.
Creator: Cullum, Alcinda Louise., Florida Atlantic University, Locsin, Rozzano
Abstract/Description: This study investigated the effect of nature-based sounds on the preoperative anxiety of 30 patients scheduled for elective surgical procedures. Preoperative anxiety was measured utilizing a visual analog scale. Of the 30 subjects who were randomly placed in either control or experimental groups, 15 subjects comprised the experimental group who were provided with nature-based sounds, and 15 subjects comprised the control group who listened to non-vocal musical sounds. Pre-test data were...
Show moreThis study investigated the effect of nature-based sounds on the preoperative anxiety of 30 patients scheduled for elective surgical procedures. Preoperative anxiety was measured utilizing a visual analog scale. Of the 30 subjects who were randomly placed in either control or experimental groups, 15 subjects comprised the experimental group who were provided with nature-based sounds, and 15 subjects comprised the control group who listened to non-vocal musical sounds. Pre-test data were collected upon admission to the preoperative area, while post-test data were collected prior to entering the operating room suite. Measurements consisting of blood pressure, heart rate, and respiratory rate were also obtained both times. Using the t-statistic, results showed significant differences in the anxiety responses and the systolic blood pressures of patients who were provided with nature-based sounds than those provided with non-vocal musical sounds. The results of this study suggest that nature-based sound decreases anxiety responses of the preoperative patient.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15390
Subject Headings: Nature sounds, Preoperative care, Music therapy
Format: Document (PDF)

Title: A numerical study of fuselage scattering effects on rotor noise.
Creator: Atalla, Noureddine., Florida Atlantic University, Glegg, Stewart A. L., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This thesis considers the effect of scattering on the sound radiation from rotating sources. The study is carried out using a combined numerical implementation of ray acoustics and the paraxial ray approximation. A detailed description of the theoretical background to these methods is presented, along with a description of their numerical implementation. Application of the method to classical problems is considered to prove the accuracy and the power of the approach. Application of the method...
Show moreThis thesis considers the effect of scattering on the sound radiation from rotating sources. The study is carried out using a combined numerical implementation of ray acoustics and the paraxial ray approximation. A detailed description of the theoretical background to these methods is presented, along with a description of their numerical implementation. Application of the method to classical problems is considered to prove the accuracy and the power of the approach. Application of the method to some typical problems involving scattering of noise from propellers and rotors is presented. It is found that for impulsive acoustic signatures the scattering effects are important especially in the sideline direction from a helicopter fuselage. The effects of sharp edges on the steady loading noise from tilt-rotor configurations indicates that there is a new mechanism for generating impulsive acoustic signatures caused by scattering by sharp edges of the fuselage. The acoustic signatures generated by this mechanism can appear very similar to other types of impulsive source generated by aerodynamic interactions on the blade and therefore must be important. This type of source can be eliminated if the fuselage has rounded edges. Flow effects on scattering problems have also been considered. It was shown that the flow causes a modification and displacement of the lobes of the directivity pattern and the shadow zone, which can be important at Mach numbers greater than 0.2. The main conclusion of this thesis is that scattering effects cannot be ignored for highly directional rotating sources next to rigid scattering objects as is always the case for propellers and helicopters rotors.
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Date Issued: 1991
PURL: http://purl.flvc.org/fcla/dt/12276
Subject Headings: Sound-waves--Scattering, Rotors--Noise
Format: Document (PDF)

Title: A volume scattering model for sediment classification through acoustic means.
Creator: Jenkins, Michael Gerard., Florida Atlantic University, LeBlanc, Lester R.
Abstract/Description: A simple model is developed to evaluate the acoustic scattering environment of sediments based on the envelope function of digital sub-bottom sonar data. Scattering pressure and intensity histograms are produced from model results. These histograms are compared to the theoretical distributions expected for scattering event pressure and intensity. Sediment composition is inferred from the determined acoustic scattering environment. The model has been applied to X-Star digital sub-bottom data...
Show moreA simple model is developed to evaluate the acoustic scattering environment of sediments based on the envelope function of digital sub-bottom sonar data. Scattering pressure and intensity histograms are produced from model results. These histograms are compared to the theoretical distributions expected for scattering event pressure and intensity. Sediment composition is inferred from the determined acoustic scattering environment. The model has been applied to X-Star digital sub-bottom data taken in the vicinity of St. John's Harbor, New Brunswick. Model results are compared to ground truth (Borehole logs) taken within the survey area. This comparison indicates general trends within the sediment scattering environment which may be linked to sediment composition. Distinct differences in model results were noted over areas of differing sediment types.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14945
Subject Headings: Sedimentation analysis, Underwater acoustics, Sound--Reverberation
Format: Document (PDF)

Title: ORIENTATION OF BLACKTIP SHARKS (CARCHARHINUS LIMBATUS) TO UNDERWATER SOUND.
Creator: Sullivan, Caroline, Kajiura, Stephen, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description: Sharks respond to low frequency pulsed sounds but are documented to lack the capacity to detect these sounds beyond the acoustic near field. The purpose of my study was to quantify the distance blacktip sharks (Carcharhinus limbatus) oriented to sound stimuli, and determine if responses occurred in the far field. Using an aerial drone and underwater speaker, C. limbatus were filmed responding to sound stimuli (100 – 200 Hz; 200 – 400 Hz; and 400 – 800 Hz). Upon detection, C. limbatus elicited...
Show moreSharks respond to low frequency pulsed sounds but are documented to lack the capacity to detect these sounds beyond the acoustic near field. The purpose of my study was to quantify the distance blacktip sharks (Carcharhinus limbatus) oriented to sound stimuli, and determine if responses occurred in the far field. Using an aerial drone and underwater speaker, C. limbatus were filmed responding to sound stimuli (100 – 200 Hz; 200 – 400 Hz; and 400 – 800 Hz). Upon detection, C. limbatus elicited a 20 – 160° turn from the speaker, and rapidly swam away. Sharks responded to all frequencies from at least 62 m, and 71.6% of all responses (n = 209) occurred in the far field. This indicates that blacktip sharks can detect and orient away from a sound stimulus at distances that extend beyond the acoustic near field, which suggests that they are not detecting sound using the inner ear otoconia.
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Date Issued: 2022
PURL: http://purl.flvc.org/fau/fd/FA00014104
Subject Headings: Blacktip shark, Carcharhinus limbatus, Underwater sound
Format: Document (PDF)

Title: Developmental types of shallow-water asteroids of McMurdo Sound, Antarctica.
Creator: Bosch, Isidro, Pearse, J. S., Harbor Branch Oceanographic Institute
Date Issued: 1990
PURL: http://purl.flvc.org/FCLA/DT/3333150
Subject Headings: Starfishes, Starfishes--Development, McMurdo Sound (Antarctica)
Format: Document (PDF)

Title: The migration behavior, fine structure, and bioluminescent activity of krill sound-scattering layers.
Creator: Greene, C. H., Widder, Edith A., Youngbluth, Marsh J., Tamse, A., Johnson, G. E.
Date Issued: 1992
PURL: http://purl.flvc.org/FCLA/DT/3343817
Subject Headings: Krill, Euphausiacea, Sound scattering layers, Echo scattering layers
Format: Document (PDF)

Title: Medusae from McMurdo sound, Ross Sea including the descriptions of two new species, Leuckartiara brownei and Benthocodon hyalinus.
Creator: Larson, R. J., Harbison, G. R., Harbor Branch Oceanographic Institute
Date Issued: 1990
PURL: http://purl.flvc.org/FCLA/DT/3333178
Subject Headings: Medusae, Species, McMurdo Sound (Antarctica), Hydrozoa
Format: Document (PDF)

Title: Inexpensive underwater data communication.
Creator: Spragg, Donald Edgar, An, Edgar
Date Issued: 2012-04-06
PURL: http://purl.flvc.org/fcla/dt/3350926
Subject Headings: Underwater data communication, Underwater acoustic communication, Sound pickup and reproduction
Format: Document (PDF)

Title: Cardiac patterns during another infant's cry sound in neonates of depressed mothers.
Creator: Cotler, Joseph, Charles E. Schmidt College of Science, Department of Psychology
Abstract/Description: Past research indicates there is a link between physiological responses and adaptive social responses to another individual's distress. Scholars have theorized that humans may be predisposed, both physiologically and behaviorally to responding to others, especially those who are in distress. Maternal depression has been associated with dysregulated emotional development and may possibly affect the physiological and behavioral responses of a neonate. The present research examined the...
Show morePast research indicates there is a link between physiological responses and adaptive social responses to another individual's distress. Scholars have theorized that humans may be predisposed, both physiologically and behaviorally to responding to others, especially those who are in distress. Maternal depression has been associated with dysregulated emotional development and may possibly affect the physiological and behavioral responses of a neonate. The present research examined the relationship between neonates' physiological and behavioral responses to naturally generated (compared to artificial) stimuli of other neonates, as well as the role of maternal depression in the responses. Specifically, heart rate, heart period, and heart period variability were measured to assess the newborns' reaction to cries generated by both other newborns and digitally modulated sources. This study found that newborns of depressed mothers had higher heart period variability and showed less behavioral distress when hearing the cry of another infant.
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Date Issued: 2013
PURL: http://purl.flvc.org/FAU/3360769
Subject Headings: Heart sounds, Auscultation, Human physiology, Depression in children, Prevention
Format: Document (PDF)

Title: AN INVESTIGATION OF THE EFFECT OF SOURCE MEASUREMENT TECHNIQUES ON THE COHERENCE FUNCTION.
Creator: BULLWINKEL, PAUL EDWARD., Florida Atlantic University, Dunn, Stanley E.
Abstract/Description: This report presents the results of an experimental investigation of the effects of using different source measurement techniques in implementing the coherence function for source identification purposes. Frequency domain measurements leading to the coherence function are developed with regard to providing a causal relation for a single input, single output, linear system. The use of a near microphone or accelerometer for source measurements is presented with particular interest paid to the...
Show moreThis report presents the results of an experimental investigation of the effects of using different source measurement techniques in implementing the coherence function for source identification purposes. Frequency domain measurements leading to the coherence function are developed with regard to providing a causal relation for a single input, single output, linear system. The use of a near microphone or accelerometer for source measurements is presented with particular interest paid to the effect of introducing noise into the input measurement. Experimental results show that while a near microphone provides a more accurate coherence statement than an accelerometer, the input of correlated noise may be a problem. The possibility of an empirical criteria for the source to noise signal difference at the near microphone is raised as a means to help avoid this problem.
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Date Issued: 1978
PURL: http://purl.flvc.org/fcla/dt/13930
Subject Headings: Spectrum analysis--Research, Sound analyzers--Research
Format: Document (PDF)

Title: Vocal behavior of captive Atlantic bottlenose dolphins in a swim program.
Creator: Boege, Deborah Dorothy., Florida Atlantic University, Bourne, Godfrey R.
Abstract/Description: Dolphins emit distinct vocalizations in the contexts of stressful situations, such as when captured in nets. It has been assumed among animal rights groups that the presence of human swimmers causes stress in captive Atlantic bottlenose dolphins (Tursiops truncatus). Stress may be expressed in dolphin vocalizations and the associated visual behaviors before, during, and after swim sessions with humans. Thus, these behaviors were recorded to elucidate quantitative vocal patterns suggestive of...
Show moreDolphins emit distinct vocalizations in the contexts of stressful situations, such as when captured in nets. It has been assumed among animal rights groups that the presence of human swimmers causes stress in captive Atlantic bottlenose dolphins (Tursiops truncatus). Stress may be expressed in dolphin vocalizations and the associated visual behaviors before, during, and after swim sessions with humans. Thus, these behaviors were recorded to elucidate quantitative vocal patterns suggestive of conspecific stress. Significant differences among vocalization types within sample sessions were found only for whistles between During II and After sessions. Other comparisons indicated no significant differences for vocalization production frequencies between the presence or absence of human swimmers. Additionally, correlations found among the seven vocalization types and all five sample sessions indicated only that one variable, i.e. the presence or absence of human swimmers, was being measured in several different ways (by the different vocalization type production frequencies). Thus, conspecific stress, if indeed it can be measured by vocalization production frequency, does not appear to occur more often in the presence of human swimmers.
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Date Issued: 1994
PURL: http://purl.flvc.org/fcla/dt/15027
Subject Headings: Bottlenose dolphin--Behavior, Animal sounds, Mammals--Behavior
Format: Document (PDF)

Title: Interaction of acoustic waves generated by coupled finite fluid-loaded plates.
Creator: Kaina, Rachid., Florida Atlantic University, Cuschieri, Joseph M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The response of fluid-loaded plates has been extensively studied in the past. However, most of the work deals with either infinite plates or finite plates with particular boundary conditions and the results are generally presented only in the limit of small wavelengths compared with the dimensions of the plates. Furthermore, the problem of coupled finite plates where both the acoustic interaction and structural interaction are included in the solution has not been considered. In this...
Show moreThe response of fluid-loaded plates has been extensively studied in the past. However, most of the work deals with either infinite plates or finite plates with particular boundary conditions and the results are generally presented only in the limit of small wavelengths compared with the dimensions of the plates. Furthermore, the problem of coupled finite plates where both the acoustic interaction and structural interaction are included in the solution has not been considered. In this dissertation the response of two coupled finite plates set in two alternative configurations is considered. The plates are simply supported on two edges, with arbitrary boundary conditions on the remaining two edges. The solutions obtained for the response of the plates include both the structural interaction at the common junction and the acoustic interaction due to the scattered pressure from each of the two plates. The results are presented in terms of the vibrational power flow into and out of each plate component. The solution is based on a formulation developed in the wavenumber domain combined with the Mobility Power Flow method. Using this approach, different substructural elements coupled under different boundary conditions to form a complex global structure can be considered. The detailed spatial and temporal scales of the structure response are not lost when using this method. In obtaining the solution for the scattering from the fluid-loaded plates, a modal decomposition in the direction normal to the simply supported edge is used. A spatial Fourier-transform decomposition is used in the other direction. Due to the finiteness of the plate, eight unknowns parameters are obtained in the transformed result. The solution for these eight unknown parameters is obtained from the boundary conditions and the condition that the response must remain finite. Two analytical approaches are used to solve the final plate integral equation. The first approach consists of an approximation method which obtains a solution based on the solution of the corresponding infinite plate problem. The second approach is a more accurate solution based on the Projection Method for the solution of integral equations. Both of the approaches used in the solution provide accurate predictions at high frequencies. At low frequencies especially for low structural damping or for heavy fluid loading, only the Projection Method gives reliable results. This is attributed to the fact that at low frequencies, the influence of the edges of the plates on the scattering is significant. The overall results obtained from this analysis indicate that the fluid loading and the plate characteristics have a significant influence on the acoustic scattering properties, especially in the case of heavy fluid loading. The application of the method to coupled fluid-loaded plates indicates that the junction enhances the scattering properties. The acoustical interaction between the coupled plates increases the contribution to scattering from subsonic wavenumber components. In the absence of the interaction, only supersonic wavenumbers contribute to the scattering. Inclusion of acousticlal interaction requires both supersonic and subsonic components. The significance of the contribution from the subsonic wavenumber components is dependent on the type of the fluid loading.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/12341
Subject Headings: Finite element method, Plates (Engineering), Acoustic emission, Sound--Transmission
Format: Document (PDF)

Title: High-Speed High-Frequency Acoustic Communications in Ports and Shallow Water.
Creator: Blue, Patrick Michael, Beaujean, Pierre-Philippe, Florida Atlantic University
Abstract/Description: A detailed study of a novel method for high-speed acoustic communications in ports and shallow water is presented. A series of field experiments, coupled with simulated results using an acoustic channel model have been conducted to outline the optimal modulation schemes for use in the highly reverberant and Doppler dominated shallow water acoustic channel. Field experiments were conducted in the vicinity of the SeaTech marina and the Port Everglades turning basin in water depths of 2 to 15...
Show moreA detailed study of a novel method for high-speed acoustic communications in ports and shallow water is presented. A series of field experiments, coupled with simulated results using an acoustic channel model have been conducted to outline the optimal modulation schemes for use in the highly reverberant and Doppler dominated shallow water acoustic channel. Field experiments were conducted in the vicinity of the SeaTech marina and the Port Everglades turning basin in water depths of 2 to 15 meters and ranges of between 25 and 75 meters. An automated FAU acoustic modem transmitted BPSK and QPSK modulated messages centered at 300 kHz, with a source level of 173 dB re 1pPa and a symbol bandwidth of 25, 50 or 75 kHz. The coded rate varied from 25000 to 150000 bits per second. These high data rates are made possible using a high resolution Decision Feedback Equalizer with an efficient Doppler compensation process. The results of this study demonstrate the ability of such a system to transmit video images in a shallow water environment.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012504
Subject Headings: Underwater acoustics, Deep-sea sounding, Seawater--Acoustic properties
Format: Document (PDF)

Title: Bio-Inspired Modified Turbulent Boundary Layers.
Creator: French, Stone A., Glegg, Stewart, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: The reduction of drag and sound pressure levels (SPL) are desirable traits in many fluidics’ applications ranging from high-speed transportation to energy generation. Inspiration has been found in some species of owls that possess boundary layer control surface treatments on their wings that appear to reduce SPL while in flight. This modification of the flow over the wings is known as the development of a modified boundary layer (MBL). Virginia Tech is working in collaboration with Florida...
Show moreThe reduction of drag and sound pressure levels (SPL) are desirable traits in many fluidics’ applications ranging from high-speed transportation to energy generation. Inspiration has been found in some species of owls that possess boundary layer control surface treatments on their wings that appear to reduce SPL while in flight. This modification of the flow over the wings is known as the development of a modified boundary layer (MBL). Virginia Tech is working in collaboration with Florida Atlantic University to investigate this reduction in SPL experimentally but requires the assistance of RANS simulation to obtain drag results. This thesis investigates the drag effects of the rod style geometries being evaluated at VT to mimic the MBL of an owl. In doing this it was found that the height of the rods has a direct correlation with the amount of drag induced by the presence of the rods in the flow field.
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Date Issued: 2021
PURL: http://purl.flvc.org/fau/fd/FA00013826
Subject Headings: Turbulent boundary layer, Sound pressure, Biomimicry, Drag (Aerodynamics)
Format: Document (PDF)

FAU Theses and Dissertations (33)	+ -
HBOI Faculty Contributions (8)	+ -
FAU Graduate Student Research (1)	+ -
FAU Undergraduate Student Research (1)	+ -

Underwater acoustics (6)	+ -
Sound--Transmission (5)	+ -
Sound (4)	+ -
Animal sounds (3)	+ -
Sound-waves--Scattering (3)	+ -

Acoustical engineering (2)	+ -
Animal communication (2)	+ -
Atlantic spotted dolphin--Behavior (2)	+ -
Dolphins--Physiology (2)	+ -
Electromagnetic waves--Scattering (2)	+ -
Faulkner, William,--1897-1962--As I lay dying (2)	+ -
Faulkner, William,--1897-1962--Sound and the fury (2)	+ -
Fish sounds (2)	+ -
McMurdo Sound (Antarctica) (2)	+ -
Signal processing (2)	+ -
Sonar (2)	+ -
Sound scattering layers (2)	+ -
Three-dimensional display systems (2)	+ -
Acoustic emission (1)	+ -
Acoustic surface waves. (1)	+ -
Acoustics (1)	+ -
Animal communication. (1)	+ -
Auscultation (1)	+ -
Bioacoustics (1)	+ -
Bioacoustics. (1)	+ -
Bioluminescence (1)	+ -
Biomimicry (1)	+ -
Blacktip shark (1)	+ -
Bottlenose dolphin--Behavior (1)	+ -
Carcharhinus limbatus (1)	+ -

Sanctuary. (1)	+ -
Sound and the fury. (1)	+ -

Electronic Thesis or Dissertation (33)	+ -
article (8)	+ -
abstract (2)	+ -

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