View All Items

Title: MULTIPHYSICS SIMULATION OF DIELECTROPHORESIS ENRICHMENT FOR DETECTION OF LOW PARASITEMIA PLASMODIUM FALCIPARUM IN HUMAN BLOOD.
Creator: Oladokun, Oladiran, Du, E., Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Malaria is an ancient lethargic disease that remains a global burden. It has been difficult to end the scourge of P. falciparum malaria because of the parasites’ drug resistance so early diagnosis of malaria is crucial. Microscopy remains the gold standard but has limited reliability in detecting malaria parasites. This study proffered a method towards detection of low parasitemia P. falciparum infected RBCs (Pf-RBCs) based on dielectrophoresis (DEP). A microfluidic device was designed for...
Show moreMalaria is an ancient lethargic disease that remains a global burden. It has been difficult to end the scourge of P. falciparum malaria because of the parasites’ drug resistance so early diagnosis of malaria is crucial. Microscopy remains the gold standard but has limited reliability in detecting malaria parasites. This study proffered a method towards detection of low parasitemia P. falciparum infected RBCs (Pf-RBCs) based on dielectrophoresis (DEP). A microfluidic device was designed for label-free cell sorting of Pf-RBCs from other whole blood in a continuous manner, based on the intrinsic electrical signatures of the cells. The design was validated by a finite element simulation using COMSOL Multiphysics. Simulations show the feasibility of the separation in a 9-mm long microfluidic channel under laminar flow conditions, using a low voltage supply of +/-10 V at 50 kHz.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014415
Subject Headings: Plasmodium falciparum, Microfluidic devices, Dielectrophoresis, Biomedical engineering, Point-of-care testing
Format: Document (PDF)

Title: MODELING, IMPLEMENTATION AND CONTROL OF A CVT BASED PTO FOR A SMALL SCALE MHK-TURBINE IN LOW FLOW SPEED OPERATION.
Creator: Pimentel, Hugo, Dhanak, Manhar, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Modeling, implementation, field testing and control of a power takeoff (PTO) device equipped with a ball-type continuously variable transmission (B-CVT) for a small marine hydrokinetic (MHK) turbine deployed from a floating unmanned autonomous mobile catamaran platform is described. The turbine is a partially submerged multi-blade undershot waterwheel (USWW). A validated numerical torque model for the MHK turbine has been derived and a speed controller has been developed, implemented and...
Show moreModeling, implementation, field testing and control of a power takeoff (PTO) device equipped with a ball-type continuously variable transmission (B-CVT) for a small marine hydrokinetic (MHK) turbine deployed from a floating unmanned autonomous mobile catamaran platform is described. The turbine is a partially submerged multi-blade undershot waterwheel (USWW). A validated numerical torque model for the MHK turbine has been derived and a speed controller has been developed, implemented and tested in the field. The dependance of the power generated as a function of number and submergence level of turbine blades has been investigated and the number of blades that maximizes power production is determined. Bench and field testing in support of characterizing the power conversion capabilities of MHK turbine and PTO are described. Detailed results of the final torque and power coefficient models, the controls architecture, and the MHK turbine performance with varying numbers of blades are provided.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014417
Subject Headings: Marine turbines, Renewable energy, Marine turbines--Transmission devices, Continuously variable transmission
Format: Document (PDF)

Title: SMALL UNMANNED MARINE HYDROKINETIC PLATFORMS FOR POWER GENERATION IN COASTAL AND TIDAL WATERS.
Creator: McKinney, Adriana, Dhanak, Manhar, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: The feasibility and optimization of small unmanned mobile marine hydrokinetic (MHK) energy platforms for harvesting marine current energy in coastal and tidal waters are examined. A case study of a platform based on the use of a free-surface waterwheel (FSWW) mounted on an autonomous unmanned surface vehicle (USV) was conducted. Such platforms can serve as recharging stations for aerial drones (UAVs), enabling extension of the UAVs’ autonomous operating time. An unmanned MHK platform...
Show moreThe feasibility and optimization of small unmanned mobile marine hydrokinetic (MHK) energy platforms for harvesting marine current energy in coastal and tidal waters are examined. A case study of a platform based on the use of a free-surface waterwheel (FSWW) mounted on an autonomous unmanned surface vehicle (USV) was conducted. Such platforms can serve as recharging stations for aerial drones (UAVs), enabling extension of the UAVs’ autonomous operating time. An unmanned MHK platform potentially meets this need with sustainable power harvested from water currents. For the case study, six different waterwheel configurations were field-tested in the Intracoastal Waterway of South Florida in support of determining the configuration that produced the most power. Required technologies for unmanned operations of the MHK platform were developed and tested. The data from the field-testing were analyzed to develop an empirical relation between the wheel’s theoretical hydrokinetic power produced and the mechanical power harnessed by the MHK platform with various waterwheel configurations during field-testing. The field data was also used to determine the electrical power generated by the FSWW configurations during field-testing. The study has led to the development of standardized testing procedures. The empirical relation is used to examine predicted power production through scaling up different physical aspects of the waterwheel.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014412
Subject Headings: Ocean engineering, Renewable energy, Marine turbines
Format: Document (PDF)

Title: EXPLORING UNDULATORY SWIMMING BEHAVIORS WITH DEEP REINFORCEMENT LEARNING.
Creator: Alvaro, Alejandro, Verma, Siddhartha, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: The capability to navigate in the proximity of solid surfaces while avoiding collision and maintaining high efficiency is essential for the effective design and operation of underwater vehicles. The underlying capability involves a variety of challenges, and a potential approach to overcome such obstacles is to rely on biomimetic or bio-inspired design. Through evolution, organisms have developed methods of locomotion optimized for their specific environment. One of the common forms of...
Show moreThe capability to navigate in the proximity of solid surfaces while avoiding collision and maintaining high efficiency is essential for the effective design and operation of underwater vehicles. The underlying capability involves a variety of challenges, and a potential approach to overcome such obstacles is to rely on biomimetic or bio-inspired design. Through evolution, organisms have developed methods of locomotion optimized for their specific environment. One of the common forms of locomotion found in underwater organisms is undulatory swimming. These undulatory swimmers display different swimming behaviors based on the flow conditions in their environment. These behaviors take advantage of changes in the flow field caused by the presence of obstructions and obstacles upstream or adjacent to the swimmer. For example, a free swimmer in near-proximity to a flat plane can experience changes in lift and drag during locomotion. The reduced drag can benefit the swimmer, however, changes in lift may lead to a collision with obstacles. Despite the abundance of qualitative data from observing these undulatory swimmers, there is a lack of quantitative data, creating a disconnect in understanding how these organisms have evolved to exploit the presence of walls and obstacles. By employing a combination of traditional computational fluid dynamics and novel neural network-based techniques it is possible to emulate the evolution of learned behavior in biological organisms. The current work uses deep reinforcement learning coupled with two-dimensional numerical simulations of self-propelled swimmers to better understand behavior observed in nature.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014402
Subject Headings: Reinforcement learning, Computational fluid dynamics, Autonomous underwater vehicles
Format: Document (PDF)

Title: FLOW-MEDIATED NAVIGATION AND COORDINATION OF ARTIFICIAL SWIMMERS USING DEEP REINFORCEMENT LEARNING.
Creator: Nair, Aishwarya, Verma, Siddhartha, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Aquatic organisms are able to achieve swimming efficiencies that are much higher than any underwater vehicle that has been designed by humans. This is mainly due to the adaptive swimming patterns that they display in response to changes in their environment and their behaviors, i.e., hunting, fleeing, or foraging. In this work, we explore these adaptations from a hydrodynamics standpoint, using numerical simulations to emulate self-propelled artificial swimmers in various flow fields. Apart...
Show moreAquatic organisms are able to achieve swimming efficiencies that are much higher than any underwater vehicle that has been designed by humans. This is mainly due to the adaptive swimming patterns that they display in response to changes in their environment and their behaviors, i.e., hunting, fleeing, or foraging. In this work, we explore these adaptations from a hydrodynamics standpoint, using numerical simulations to emulate self-propelled artificial swimmers in various flow fields. Apart from still or uniform flow, the most likely flow field encountered by swimmers are those formed by the wakes of solid objects, such as roots of aquatic vegetation, or underwater structures. Therefore, a simplified bio-inspired design of porous structures consisting of nine cylinders was considered to identify arrangements that could produce wakes of varying velocities and enstrophy, which in turn might provide beneficial environments for underwater swimmers. These structures were analyzed using a combination of numerical simulations and experiments, and the underlying flow physics was examined using a variety of data-analysis techniques. Subsequently, in order to recreate the adaptations of natural swimmers in different flow regimes, artificial swimmers were positioned in each of these different types of flow fields and then trained to optimize their movements to maximize swimming efficiency using deep reinforcement learning. These artificial swimmers utilize a sensory input system that allows them to detect the velocity field and pressure on the surface of their body, which is similar to the lateral line sensing system in biological fish. The results demonstrate that the information gleaned from the simplified lateral line system was sufficient for the swimmer to replicate naturally found behaviors such as K´arm´an gaiting. The phenomenon of schooling in underwater organisms is similarly thought to provide opportunities for swimmers to increase their energy efficiency, along with the other associated benefits. Thus, multiple swimmers were trained using multi-agent reinforcement learning to discover optimal swimming patterns at the group level as well as the individual level.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014413
Subject Headings: Reinforcement learning, Hydrodynamics, Computational fluid dynamics, .
Format: Document (PDF)

Title: THE DETECTABILITY OF GOLIATH GROUPER SOUNDS IN NEARSHORE WATERS USING A NORMAL MODES PROPAGATION MODEL.
Creator: Marcheggiani, Joseph P., Cherubin, Laurent, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: This research presents findings from an in-situ experiment utilizing a hydrophone line array to capture the sound production of the Goliath grouper. Analysis revealed that Goliath grouper calls exhibit multiple frequency components, including one high-amplitude component and 2 to 3 low-amplitude components. The primary high-amplitude component is concentrated in the 30 to 70 Hz band, peaking around 50 Hz, while low-amplitude components span 20 to 30 Hz, 70 to 115 Hz, and 130 to 200 Hz....
Show moreThis research presents findings from an in-situ experiment utilizing a hydrophone line array to capture the sound production of the Goliath grouper. Analysis revealed that Goliath grouper calls exhibit multiple frequency components, including one high-amplitude component and 2 to 3 low-amplitude components. The primary high-amplitude component is concentrated in the 30 to 70 Hz band, peaking around 50 Hz, while low-amplitude components span 20 to 30 Hz, 70 to 115 Hz, and 130 to 200 Hz. Comparison between in-situ data and results from a normal modes transmission loss model identified regions where echo level increased with propagation distance. This suggests that the loudness of the call may not necessarily indicate proximity, indicating the Goliath grouper might rely on other cues for localization, such as changes in the frequency profile of its call. Two methods for estimating call distance are presented. The first method vi utilized a transmission loss model and measured transmission loss across a hydrophone line array. This method could also determine the source level of the calls, yielding source level estimates ranging from 124.01 to 144.83 dB re 1 μPa. The second method employed match field filtering, validating the accuracy of the transmission loss model. Both methods produced similar call distance estimations, ranging from 11.5 to 17.1 meters, placing the grouper inside or near its typical habitat.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014377
Subject Headings: Epinephelus itajara, Groupers, Fish sounds, Acoustics, Sound--Transmission
Format: Document (PDF)

Title: INFLUENCE OF DEFORMATION CONSTRAINTS OF HONEYCOMB CORE CELLS ON THE BENDING STIFFNESS OF SINGLE-FACE SANDWICH.
Creator: Ayanoglu, Mustafa Oguzhan, Carlsson, Leif A., Du, E, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: This research focuses on deformation constraints of honeycomb core cells in a sandwich imposed by bonds to the face sheets. Specifically, the influence of one-sided core constraints on the bending stiffness of a single-face honeycomb core sandwich is examined. To characterize the unconstrained in-plane compressive response of honeycomb core, a range of honeycomb cores was experimentally examined. Cores with a thin cell wall displayed extensive bending deformation of inclined cell walls while...
Show moreThis research focuses on deformation constraints of honeycomb core cells in a sandwich imposed by bonds to the face sheets. Specifically, the influence of one-sided core constraints on the bending stiffness of a single-face honeycomb core sandwich is examined. To characterize the unconstrained in-plane compressive response of honeycomb core, a range of honeycomb cores was experimentally examined. Cores with a thin cell wall displayed extensive bending deformation of inclined cell walls while cores with thicker walls failed by a shear-type instability of the cells indicated by tilting of vertical cell wall segments. The modulus and compressive strength of the core were compared to the predictions from unit cell models. The results show that geometrical imperfections such as deviation from the intended cell wall angle cause in-plane anisotropy and have strong influence on modulus and strength of the core. Modulus and strength were in reasonable agreement with predictions from unit cell models for cell wall modulus and strength between 5-12 GPa and 72-171 MPa for the set of cores examined.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014438
Subject Headings: Honeycomb structures, Materials--Compression testing, Sandwich construction
Format: Document (PDF)

Title: ATTITUDE MEASURING SENSOR FOR A TOWED BODY.
Creator: Flitton, Garrett, Dhanak, Manhar, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: The Design and Development of a remote attitude-measuring sensor package (RASP) for use onboard an underwater tow fish to analyze its dynamic movement while towing is described. The RASP will be used to determine the orientation, acceleration, and gyroscopic attitude of the tow fish. The collection of this data is important for understanding the trim of the tow fish under different towing conditions behind a manned surface vessel or unmanned underwater vehicle. The trim data acquired will...
Show moreThe Design and Development of a remote attitude-measuring sensor package (RASP) for use onboard an underwater tow fish to analyze its dynamic movement while towing is described. The RASP will be used to determine the orientation, acceleration, and gyroscopic attitude of the tow fish. The collection of this data is important for understanding the trim of the tow fish under different towing conditions behind a manned surface vessel or unmanned underwater vehicle. The trim data acquired will inform the extent to which post-processing of collected three-axis electromagnetic field data would be required. The RASP has been analyzed in the laboratory with a mechanical testing rig that was designed and built to validate the accuracy and performance of the entire sensor package system. The developed package will aid in the assessment of the performance of the tow fish in field operations with the sensor package implemented on the tow fish.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014423
Subject Headings: Sensors, Marine towing, Electromagnetic fields
Format: Document (PDF)

Title: BACKGROUND STRUCTURE FUNCTIONS, A BASIS TO REDUCE ACOUSTIC POWER REQUIREMENTS AND IMPROVE IMAGES.
Creator: Kobold, Michael C., Beaujean, Pierre-Philippe J., Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Background Structure Functions (BSFs) are wavefront distortion metrics, functions of Sound Speed Profiles (SSPs) that are functions of depth. Use of these BSFs is a synthesis form of Matched Field Processing (MFP) that detects signals that are otherwise lost to receivers. Underwater Acoustics (UWA) can use these models to forecast communication and imaging performance and to reduce power radiated into the sea. This reduction of Transmission Loss (TL) occurs because the commercial wavefront...
Show moreBackground Structure Functions (BSFs) are wavefront distortion metrics, functions of Sound Speed Profiles (SSPs) that are functions of depth. Use of these BSFs is a synthesis form of Matched Field Processing (MFP) that detects signals that are otherwise lost to receivers. Underwater Acoustics (UWA) can use these models to forecast communication and imaging performance and to reduce power radiated into the sea. This reduction of Transmission Loss (TL) occurs because the commercial wavefront control has an input format that accepts BSFs. The BSF plots represent the purely statistical distortion for communications and remote sensing. Another source of TL reduction comes from the enclosed BSF-based phase and phase variance forecasting that protects equalizers from losing phase-lock. Protecting the equalizers protects the Signal To Noise (SNR) ratios. This dissertation derives the UWA version of these metrics and applies them to the following locations of our SSPs: The BSFs use measured, corrected, and verified SSP groups for 132 different locations in the Atlantic Ocean and the Gulf of Mexico from a Navy Ocean Atlas, as well as 64 SSPs in two areas in the littorals, Port Everglades, and Saint Andrew Bay, plus tidal variations. Since BSFs digitize the propagation into one or more segments, our purely statistical phase screen model uses only 3 or 4 degrees of freedom (DOFs) per segment compared to many dozen DOFs for conventional structure functions. The BSFs forecast communications and imaging performance, including range, in locations where acoustic measurements are not available, but SSPs are. A separate algorithm forecasts Gouy phase anomalies from background SSPs, which otherwise requires a priori knowledge of anomaly location and use of Catastrophe theory due to ray theory failure at focuses. Avoiding these anomalies and loss of Phase-Locked Loops (PLLs) also helps maintain SNR and lowers transmission power requirements. Combining with phase parameters and performance forecasts improves UWA propagation efficiency using the background (SSPs). In a spatial version of delay equalization, BSF analysis also produces the enclosed Shear Distortion Ratios (SDRs) for the same locations mentioned above, to allow optimum selection of image enhancement algorithms that mitigate image shear distortion.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014395
Subject Headings: Underwater acoustics, Sound--Speed, Ocean engineering
Format: Document (PDF)

Title: NANOPARTICLE-INDUCED CATALYTIC CARBON CAPTURE: A MICROFLUIDICS APPROACH.
Creator: Donjuan, Joshua, Kim, Myeongsub, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Due to technological advancement, energy consumption and demand have been increasing significantly, primarily satisfied by fossil fuel consumption. This reliance on fossil fuels results in substantial greenhouse gas emissions, with CO₂ being the most prominent contributor to global warming. To mitigate this issue and prevent CO₂ emissions, Carbon Capture, Utilization, and Storage (CCUS) technologies are employed. Among these, the amine scrubbing method is widely used due to its high CO2...
Show moreDue to technological advancement, energy consumption and demand have been increasing significantly, primarily satisfied by fossil fuel consumption. This reliance on fossil fuels results in substantial greenhouse gas emissions, with CO₂ being the most prominent contributor to global warming. To mitigate this issue and prevent CO₂ emissions, Carbon Capture, Utilization, and Storage (CCUS) technologies are employed. Among these, the amine scrubbing method is widely used due to its high CO2 capture efficiency and regenerative ability. However, this method has drawbacks, including high toxicity, corrosion, and substantial freshwater consumption. To develop an environmentally sustainable carbon capture solution, researchers are exploring alternatives such as the use of seawater and enhanced CO2 capture with catalysts. In this study, we analyze the catalytic performance of nickel nanoparticles (NiNPs) in seawater with carboxymethyl cellulose (CMC) polymers. Using flow-focusing geometry-based microfluidic channels, we investigated CO₂ dissolution at various concentrations of nanoparticles and CMC polymers. The objective is to optimize the concentration of nanoparticles and CMC polymers for effective CO₂ dissolution. We utilized NiNPs with diameters of 100 nm and 300 nm in CMC concentrations of 100 ml/L, 200 ml/L, and 300 ml/L. Additionally, NiNP concentrations ranging from 6 mg/L to 150 mg/L were tested for CO₂ dissolution in seawater. The results indicated that a concentration of 10 mg/L NiNPs in 100 mg/L CMC provided a CO₂ dissolution of 57%, the highest for this specific CMC concentration. At CMC concentrations of 200 ml/L and 300 ml/L, NiNP concentrations of 70 mg/L and 90 mg/L achieved CO₂ dissolution rates of 58.8% and 67.2%, respectively.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014483
Subject Headings: Carbon sequestration, Global warming, Polymer chemistry, Nanoparticles
Format: Document (PDF)

Title: SPONTANEOUS HYDROGEN GENERATION WITH SILICON NANOPARTICLES AND WATER.
Creator: Axelrod, Kevin Eric, Kim, Myeongsub, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Over the past decade, hydrogen gas generation has been a critical component toward clean energy due to its high specific energy content. Generating hydrogen gas from water is crucial for future applications, including space transportation. Recent studies show promising results using silicon nanoparticles (SiNPs) for spontaneous hydrogen generation, but most methods require external energy like high temperature or pressure. In this work, we investigated hydrogen production from SiNPs without...
Show moreOver the past decade, hydrogen gas generation has been a critical component toward clean energy due to its high specific energy content. Generating hydrogen gas from water is crucial for future applications, including space transportation. Recent studies show promising results using silicon nanoparticles (SiNPs) for spontaneous hydrogen generation, but most methods require external energy like high temperature or pressure. In this work, we investigated hydrogen production from SiNPs without external energy by leveraging high pH water using sodium hydroxide and optimizing the process with a microfluidic approach. When comparing the physical dispersion methods using the 0.1 mg/mL case, ultrasonic bath produced more hydrogen than magnetic stirrer. In this thesis, 0.01% dextran with pure SiNPs at concentrations of 0.1 mg/mL, 0.2 mg/mL, and 0.3 mg/mL was analyzed. The highest concentration with dextran generated at least 40% less hydrogen than silicon alone, thus dextran did not increase hydrogen gas.
Show less
Date Issued: 2024
PURL: http://purl.flvc.org/fau/fd/FA00014480
Subject Headings: Hydrogen, Hydrogen as fuel, Silicon, Nanoparticles
Format: Document (PDF)

Title: Acoustic Tonal and Vector Properties of Red Hind Grouper Vocalizationd.
Creator: Matthews, Cameron Anthony, Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Vertebrates are the most prodigious vocalizing animals in existence, and the most diverse methods of acoustic communication among vertebrates can be found in the ocean. Relatively many teleost fish are gifted with the ability to communicate acoustically, and the family of serranidae often performs this as a function of the swim bladder. Epinephelus Guttatus (E. guttatus), or more commonly the red hind grouper, is equipped with a drum shaped swim bladder acting as a monopole under typical...
Show moreVertebrates are the most prodigious vocalizing animals in existence, and the most diverse methods of acoustic communication among vertebrates can be found in the ocean. Relatively many teleost fish are gifted with the ability to communicate acoustically, and the family of serranidae often performs this as a function of the swim bladder. Epinephelus Guttatus (E. guttatus), or more commonly the red hind grouper, is equipped with a drum shaped swim bladder acting as a monopole under typical ocean conditions. This configuration allows for what is understood to be omnidirectional projection of tones approximately centered between 40 and 440 Hz and spanning anywhere from 40 to 200 Hz of bandwidth and modulation effects based on observed data provided by researchers. Prior studies on many other fish show correlation in acoustic communication profile with length, size and sexual identity. In the red hind, sexual dimorphism leads to an inherent female identity in all juvenile fish which converts to male according to environmental factors, recommending at least consistent organs across both sexes be assumed even if not in use. Much research has been performed on male fish vocalization in terms of spectral content. Communication in fish is a complex multi-modal process, with acoustic communication being important for many of the species, particularly those in the littoral regions of the worlds’ oceans. If identifying characteristics of the red hind vocalization can be isolated based on detection, classification, tracking and localizing methodologies, then these identifying characteristics may indeed lead to passive feature identification that allows for estimation of individual fish mass. Hypotheses based on vector, cyclostationary and classical tonal mechanics are presented for consideration. A battery of test data collection events, applying pre-recorded fish vocalizations to a geolocated undersea sound source were conducted. The results are supplied with the intent of validating hypothesis in a non-expert system manner that shows how a series of biological metrics may be assessed for detection, classification, localization and mass estimation for an individual vocalizing red hind grouper
Show less
Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00004826, http://purl.flvc.org/fau/fd/FA00004826
Subject Headings: Wave-motion, Theory of., Sound production by animals., Fishes--Vocalization., Bioacoustics., Animal communication., Underwater acoustics., Acoustic surface waves.
Format: Document (PDF)

Title: Propulsive performance of an under-actuated robotic ribbon fin.
Creator: Liu, Hanlin, Curet, Oscar M
Date Issued: 2017-06-02
PURL: http://purl.flvc.org/fau/flvc_fau_islandoraimporter_10.1088_1748-3190_aa7184_1642527109
Format: Document (PDF)

Title: Motion-Compensated Acoustic Positioning in Very Shallow Waters Using Spread-Spectrum Signaling and a Tetrahedral Ultrashort Baseline Array.
Creator: Beaujean, Pierre-Philippe J., Bon, Antoine, An, Edgar
Date Issued: 2010-09-01
PURL: http://purl.flvc.org/fau/flvc_fau_islandoraimporter_10.4031_MTSJ.44.5.4_1629744733
Format: Citation

Title: The Comprehensive Evaluation of Performance and Environmental Influence on MPSK Modulated High-Speed Acoustic Communications in Shallow Water.
Creator: Proteau, Joshua C., Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A daily study spanning a month of the shallow water acoustic channel was conducted to estimate the environmental influence on performance of an underwater acoustic communications system. An automated acoustic modem transmitted phase-coherent modulated sequences of identical data with 186 dB re IpPa source level, at coded rates from 4000 to 16000 bits/s with 4 or 8 kHz symbol bandwidth, three times daily for a month. A 64 channel Mills-Cross receiver array was used with horizontal and vertical...
Show moreA daily study spanning a month of the shallow water acoustic channel was conducted to estimate the environmental influence on performance of an underwater acoustic communications system. An automated acoustic modem transmitted phase-coherent modulated sequences of identical data with 186 dB re IpPa source level, at coded rates from 4000 to 16000 bits/s with 4 or 8 kHz symbol bandwidth, three times daily for a month. A 64 channel Mills-Cross receiver array was used with horizontal and vertical beams each containing 32 and 33 elements respectively, spaced 0.03 meters apart, with a sampling frequency of 72 kHz. Source and receiver were deployed at depths of 20 meters respectively, with a 720 meter separation range. Environmental measurements of wind velocity and direction, surface wave activity, current and sound velocity profiles, and tidal measurements were performed. Results demonstrate reliable achievement of high data-rate shallow water acoustic communications using phase-coherent modulation techniques.
Show less
Date Issued: 2006
PURL: http://purl.flvc.org/fau/fd/FA00012541
Subject Headings: Underwater acoustics--Measurement, Artificial satellites in telecommunication, Underwater acoustic telemetry, Signal processing--Digital techniques
Format: Document (PDF)

Title: Numerical Simulation of an Ocean Current Turbine Operating in a Wake Field.
Creator: Pyakurel, Parakram, VanZwieten, James H., Dhanak, Manhar R., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: An Ocean Current Turbine (OCT) numerical simulation for creating, testing and tuning flight and power takeoff controllers, as well as for farm layout optimization is presented. This simulation utilizes a novel approach for analytically describing oceanic turbulence. This approach has been integrated into a previously developed turbine simulation that uses unsteady Blade Element Momentum theory. Using this, the dynamical response and power production of a single OCT operating in ambient...
Show moreAn Ocean Current Turbine (OCT) numerical simulation for creating, testing and tuning flight and power takeoff controllers, as well as for farm layout optimization is presented. This simulation utilizes a novel approach for analytically describing oceanic turbulence. This approach has been integrated into a previously developed turbine simulation that uses unsteady Blade Element Momentum theory. Using this, the dynamical response and power production of a single OCT operating in ambient turbulence is quantified. An approach for integrating wake effects into this single device numerical simulation is presented for predicting OCT performance within a farm. To accomplish this, far wake characteristics behind a turbine are numerically described using analytic expressions derived from wind turbine wake models. These expressions are tuned to match OCT wake characteristics calculated from CFD analyses and experimental data. Turbine wake is characterized in terms of increased turbulence intensities and decreased mean wake velocities. These parameters are calculated based on the performance of the upstream OCT and integrated into the environmental models used by downstream OCT. Simulation results are presented that quantify the effects of wakes on downstream turbine performance over a wide range of relative downstream and cross stream locations for both moored and bottom mounted turbine systems. This is done to enable the development and testing of flight and power takeoff controllers designed for maximizing energy production and reduce turbine loadings.
Show less
Date Issued: 2016
PURL: http://purl.flvc.org/fau/fd/FA00004737, http://purl.flvc.org/fau/fd/FA00004737
Subject Headings: Turbulence--Mathematical models., Marine turbines--Mathematical models., Wind turbines--Aerodynamics--Mathematical models., Structural dynamics., Computational fluid dynamics., Fluid dynamic measurements., Atmospheric circulation.
Format: Document (PDF)

Title: Optimization of an Ocean Current Turbine Design and Prediction of Wake Propagation in an Array.
Creator: Kawssarani, Ali, VanZwieten, James H., Seiffert, Betsy, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This research focused on maximizing the power generated by an array of ocean current turbines. To achieve this objective, the produced shaft power of an ocean current turbine (OCT) has been quantified using CFD without adding a duct, as well as over a range of duct geometries. For an upstream duct, having a diameter 1.6 times the rotor diameter, the power increased by 8.35% for a duct that extends 1 diameter upstream. This research also focused on turbine array optimization, providing a...
Show moreThis research focused on maximizing the power generated by an array of ocean current turbines. To achieve this objective, the produced shaft power of an ocean current turbine (OCT) has been quantified using CFD without adding a duct, as well as over a range of duct geometries. For an upstream duct, having a diameter 1.6 times the rotor diameter, the power increased by 8.35% for a duct that extends 1 diameter upstream. This research also focused on turbine array optimization, providing a mathematical basis for calculating the water velocity within an array of OCTs. After developing this wake model, it was validated using experimental data. As the downstream distance behind the turbine increases, the analytic results become closer to the experimental results, with a difference of 3% for TI = 3% and difference of 4% for TI = 15%, both at a downstream distance of 4 rotor diameters.
Show less
Date Issued: 2018
PURL: http://purl.flvc.org/fau/fd/FA00013077
Subject Headings: Turbines--Design and construction., Marine turbines., Ocean current energy, Ocean wave power
Format: Document (PDF)

Title: Spectral evaluation of motion compensated adv systems for ocean turbulence measurements.
Creator: Egeland, Matthew Nicklas, von Ellenrieder, Karl, VanZwieten, James H., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A motion compensated ADV system was evaluated to determine its ability to make measurements necessary for characterizing the variability of the ambient current in the Gulf Stream. The impact of IMU error relative to predicted turbulence spectra was quantified, as well as and the ability of the motion compensation approach to remove sensor motion from the ADV measurements. The presented data processing techniques are shown to allow the evaluated ADV to be effectively utilized for quantifying...
Show moreA motion compensated ADV system was evaluated to determine its ability to make measurements necessary for characterizing the variability of the ambient current in the Gulf Stream. The impact of IMU error relative to predicted turbulence spectra was quantified, as well as and the ability of the motion compensation approach to remove sensor motion from the ADV measurements. The presented data processing techniques are shown to allow the evaluated ADV to be effectively utilized for quantifying ambient current fluctuations from 0.02 to 1 Hz (50 to 1 seconds) for dissipation rates as low as 3x10-7. This measurement range is limited on the low frequency end by IMU error, primarily by the calculated transformation matrix, and on the high end by Doppler noise. Inshore testing has revealed a 0.37 Hz oscillation inherent in the towfish designed and manufactured as part of this project, which can nearly be removed using the IMU.
Show less
Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004191, http://purl.flvc.org/fau/fd/FA00004191
Subject Headings: Fluid dynamic measurements, Fluid mechanics -- Mathematical models, Motion control systems, Ocean atmosphere interaction, Ocean circulation, Turbulence, Wave motion, Theory of
Format: Document (PDF)

Title: Evolution and application of a parallel algorithm for explicit transient finite element analysis on SIMD/MIMD computers.
Creator: Das, Partha S., Florida Atlantic University, Case, Robert O., Tsai, Chi-Tay, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The development of a parallel data structure and an associated elemental decomposition algorithm for explicit finite element analysis for massively parallel SIMD computer, the DECmpp 12000 (MasPar MP-1) machine, is presented, and then extended to implementation on the MIMD computer, Cray-T3D. The new parallel data structure and elemental decomposition algorithm are discussed in detail and is used to parallelize a sequential Fortran code that deals with the application of isoparametric...
Show moreThe development of a parallel data structure and an associated elemental decomposition algorithm for explicit finite element analysis for massively parallel SIMD computer, the DECmpp 12000 (MasPar MP-1) machine, is presented, and then extended to implementation on the MIMD computer, Cray-T3D. The new parallel data structure and elemental decomposition algorithm are discussed in detail and is used to parallelize a sequential Fortran code that deals with the application of isoparametric elements for the nonlinear dynamic analysis of shells of revolution. The parallel algorithm required the development of a new procedure, called an 'exchange', which consists of an exchange of nodal forces at each time step to replace the standard gather-assembly operations in sequential code. In addition, the data was reconfigured so that all nodal variables associated with an element are stored in a processor along with other element data. The architectural and Fortran programming language features of the MasPar MP-1 and Cray-T3D computers which are pertinent to finite element computations are also summarized, and sample code segments are provided to illustrate programming in a data parallel environment. The governing equations, the finite element discretization and a comparison between their implementation on Von Neumann and SIMD-MIMD parallel computers are discussed to demonstrate their applicability and the important differences in the new algorithm. Various large scale transient problems are solved using the parallel data structure and elemental decomposition algorithm and measured performances are presented and analyzed in detail. Results show that Cray-T3D is a very promising parallel computer for finite element computation. The 32 processors of this machine shows an overall speedup of 27-28, i.e. an efficiency of 85% or more and 128 processors shows a speedup of 70-77, i.e. an efficiency of 55% or more. The Cray-T3D results demonstrated that this machine is capable of outperforming the Cray-YMP by a factor of about 10 for finite element problems with 4K elements, therefore, the method of developing the parallel data structure and its associated elemental decomposition algorithm is recommended for implementation on other finite element code in this machine. However, the results from MasPar MP-1 show that this new algorithm for explicit finite element computations do not produce very efficient parallel code on this computer and therefore, the new data structure is not recommended for further use on this MasPar machine.
Show less
Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/12500
Subject Headings: Finite element method, Algorithms, Parallel computers
Format: Document (PDF)

Title: The finite element method as a parametric tool in the design and analysis of a pressure vessel having a threaded closure.
Creator: Merkl, Garrett Andrew., Florida Atlantic University, Case, Robert O., Tsai, Chi-Tay, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The finite element method is a very powerful tool used to analyze a variety of problems in engineering. This thesis looks at the finite element method as a tool and several important modeling features of concern. A well known finite element software package, ANSYS, will be used to demonstrate a diverse number of its capabilities, and several procedures followed in solving a specific engineering problem. The subject matter involves a nonlinear contact analysis of a pressure vessel having a...
Show moreThe finite element method is a very powerful tool used to analyze a variety of problems in engineering. This thesis looks at the finite element method as a tool and several important modeling features of concern. A well known finite element software package, ANSYS, will be used to demonstrate a diverse number of its capabilities, and several procedures followed in solving a specific engineering problem. The subject matter involves a nonlinear contact analysis of a pressure vessel having a threaded closure. The choice of this application is prompted by an interest in better understanding how the finite element method is implemented in the design and analysis of different pressure vessel parameters. A parametric finite element analysis was performed. Load and stress distributions along the threaded region of the vessel were examined for parameters including number of threads, thread pitch, diameter ratio, closure plug length, and thread profile.
Show less
Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15243
Subject Headings: Finite element method, Pressure vessels--Design and construction, Strains and stresses--Mathematical models
Format: Document (PDF)

FAU Theses and Dissertations (653)	+ -
FAU College Collections (23)	+ -
Open Educational Resources (1)	+ -

Fluid dynamics (35)	+ -
Mathematical models (28)	+ -
Underwater acoustics (23)	+ -
Finite element method (21)	+ -
Composite materials (20)	+ -

Testing (20)	+ -
Hydrodynamics (18)	+ -
Structural dynamics (18)	+ -
Fracture mechanics (17)	+ -
Design and construction (16)	+ -
Reinforced concrete (15)	+ -
Computational fluid dynamics (14)	+ -
Oceanographic submersibles (14)	+ -
Turbulence (14)	+ -
Adaptive signal processing (13)	+ -
Marine turbines (13)	+ -
Cathodic protection (12)	+ -
Vortex-motion (12)	+ -
Steel--Corrosion (11)	+ -
Corrosion and anti-corrosives (10)	+ -
Reinforced concrete--Corrosion (10)	+ -
Robotics (10)	+ -
Strains and stresses (10)	+ -
Underwater navigation (10)	+ -
Wave motion, Theory of (10)	+ -
Florida Atlantic University -- History (9)	+ -
Renewable energy sources (9)	+ -
Sandwich construction (9)	+ -
Underwater acoustic telemetry (9)	+ -
Vibration (9)	+ -

Florida (2)	+ -
Florida, Straits of (1)	+ -
Gulf Stream (1)	+ -
Planning (1)	+ -
United States (1)	+ -

Electronic Thesis or Dissertation (653)	+ -
article (12)	+ -
Program Review (9)	+ -
open educational resource (1)	+ -

Search In

Pages

Pages

Sort Results By:

Narrow results by:

Collection

Topical Subject

Geographic Subject

Genre Subject

Genre

Type of Resource

Language

Creator

Format

Owner