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Title: Analysis of ship hull and plate vibrations caused by wave forces.
Creator: Lakitosh, Fnu, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: In the present dissertation, the hydrodynamic and hydro-elastic characteristics of ship hull and plate vibrations are analyzed using theoretical and numerical methods. The wave forces are determined using a suite of methods which include the Froude-Krylov method for incident wave forces, Wagner's method and ABS rules for the slamming wave force, and numerical methods for nonlinear wave radiation forces. Finite difference methods are developed to determine the wave forced vibrations of ship...
Show moreIn the present dissertation, the hydrodynamic and hydro-elastic characteristics of ship hull and plate vibrations are analyzed using theoretical and numerical methods. The wave forces are determined using a suite of methods which include the Froude-Krylov method for incident wave forces, Wagner's method and ABS rules for the slamming wave force, and numerical methods for nonlinear wave radiation forces. Finite difference methods are developed to determine the wave forced vibrations of ship hull plates which are modeled using a range of plate theories including nonlinear plate theory with and without material damping and orthotropic plate theory for stiffened hull plates. For small amplitude deformation of thin plates, a semi-theoretical superposition method is used to determine the free and forced vibrations. The transient ship hull vibration due to whipping is also analyzed using the finite difference method. Results, in the form of deformations and stress distributions, are obtained for a range of scantling and wave parameters to identify key parameters to consider in ship structural design.
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Date Issued: 2012
PURL: http://purl.flvc.org/FAU/3342196
Subject Headings: Vibration (Marine engineering), Hulls (Naval architecture), Ships, Hydraulic impact, Ocean waves, Mathematical models, Fluid dynamics, Mathematical models
Format: Document (PDF)

Title: Analysis of the influence of voids on the hygroelastic properties of paper.
Creator: Subramanian, Lakshmikanthan., Florida Atlantic University, Carlsson, Leif A., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The influence of voids on the hygroelastic properties of paper has been investigated using analytical and numerical methods. Paper was modeled as a laminate made of cell-wall layers. A continuous fiber orientation distribution was introduced into the laminate model to derive the baseline properties of the papersheet. The voids in the papersheet were modeled as reinforcements with zero elastic properties. The reduction of elastic stiffnesses of isotropic materials containing different shapes...
Show moreThe influence of voids on the hygroelastic properties of paper has been investigated using analytical and numerical methods. Paper was modeled as a laminate made of cell-wall layers. A continuous fiber orientation distribution was introduced into the laminate model to derive the baseline properties of the papersheet. The voids in the papersheet were modeled as reinforcements with zero elastic properties. The reduction of elastic stiffnesses of isotropic materials containing different shapes and volume fractions of pores were analyzed using Voigt, Reuss, foam and combination models. Hashin's two-phase bounding model and Christensen's three-phase self-consistent models were also used to predict the elastic stiffnesses of isotropic porous materials. The influence of voids on the engineering constants of orthotropic materials was analyzed using 2-D and 3-D finite element models. The invariance of hygroexpansion in the presence of voids was demonstrated using analytical and numerical methods. The theoretical model predictions were correlated with previously published experimental results.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14915
Subject Headings: Paper, Papermaking, Micromechanics
Format: Document (PDF)

Title: Analysis of Turbulence Observed in the Florida Current using an ADCP.
Creator: Denton, John E., Dhanak, Manhar, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The observation of turbulence in the Florida Current is presented with the use of velocity measurements collected with an Acoustic Doppler Current Profiler (ADCP). The research is conducted through application of the theories of Taylor and Kolmogorov and related derivations, and processing tools of MATLAB software to this Eulerian observation of flow [1]. The velocity profile of the Florida Current is deduced in terms of its turbulent character with shear, acceleration, gradient, Reynolds...
Show moreThe observation of turbulence in the Florida Current is presented with the use of velocity measurements collected with an Acoustic Doppler Current Profiler (ADCP). The research is conducted through application of the theories of Taylor and Kolmogorov and related derivations, and processing tools of MATLAB software to this Eulerian observation of flow [1]. The velocity profile of the Florida Current is deduced in terms of its turbulent character with shear, acceleration, gradient, Reynolds Number, Reynolds Stress, Welch power spectrum density of current velocity, wavenumbers of Taylor’s hypothesis and Kolmogorov, wavenumber spectrum, eddy diameters, diapycnal diffusivity, and the Richardson Number. Processing methods are validated with results of other research conducted in the Florida Current with the use of a Multi-Scale Profiler, and an Advanced Microstructure Profiler for determination of shear, dissipation, diffusivity, and estimates of turbulent eddy diameters based on Taylor’s Hypothesis [1][4]. A spectral analysis is developed and is compared with Kolmogorov’s -5/3-Law. The process and the results of the analysis are described.
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Date Issued: 2018
PURL: http://purl.flvc.org/fau/fd/FA00013173
Subject Headings: Florida Current, Turbulence--Measurement, Underwater acoustics--Data processing, Doppler effect
Format: Document (PDF)

Title: An analytical and experimental investigation of a multicellular box beam bridge system using an acrylic model.
Creator: Ravichandran, T. V., Florida Atlantic University, Reddy, Dronnadula V., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This thesis presents an experimental investigation of a 1: 20 scale acrylic model to study the behavior of a multicellular box beam bridge system. The design of a 1: 2 scale concrete model is presented in the early part of the thesis. The acrylic model was tested under simulated AASHTO HS 20-44 loading. The load distribution characteristics of the bridge system was evaluated based on the strains and deflections at various points on the bridge model. The experimental results are presented by...
Show moreThis thesis presents an experimental investigation of a 1: 20 scale acrylic model to study the behavior of a multicellular box beam bridge system. The design of a 1: 2 scale concrete model is presented in the early part of the thesis. The acrylic model was tested under simulated AASHTO HS 20-44 loading. The load distribution characteristics of the bridge system was evaluated based on the strains and deflections at various points on the bridge model. The experimental results are presented by transverse distribution curves of strains and deflections for various load locations. Grillage analysis of the bridge system was performed and the results compared well with the experimental values.
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Date Issued: 1988
PURL: http://purl.flvc.org/fcla/dt/14445
Subject Headings: Bridges, Box girder--Design and construction
Format: Document (PDF)

Title: Analytical and experimental studies on the static and fatigue behavior of precast prestressed concrete multibox beam bridge system.
Creator: Kozhikote, Ramkumar P., Florida Atlantic University, Arockiasamy, Madasamy, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The feasibility of the use of precast prestressed concrete multi-box beams with transverse post tensioning is examined for a medium span bridge system based on analytical and experimental studies on a 1:2.5 scale model. Constant amplitude fatigue loading was applied on the model at typical locations simulating HS20-44 AASHTO truck loading. The performance of the bridge system was evaluated in terms of deflections, strains in the concrete, wheel load distribution, and behavior of longitudinal...
Show moreThe feasibility of the use of precast prestressed concrete multi-box beams with transverse post tensioning is examined for a medium span bridge system based on analytical and experimental studies on a 1:2.5 scale model. Constant amplitude fatigue loading was applied on the model at typical locations simulating HS20-44 AASHTO truck loading. The performance of the bridge system was evaluated in terms of deflections, strains in the concrete, wheel load distribution, and behavior of longitudinal joints with increasing number of cycles of fatigue loading. A grillage analysis of the bridge system was carried out to predict the elastic behavior and the cracking moments and the results compared with the experimental values.
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Date Issued: 1989
PURL: http://purl.flvc.org/fcla/dt/14512
Subject Headings: Prestressed concrete beams--Fatique, Bridges, Box girder, Box beams
Format: Document (PDF)

Title: Analytical studies of concrete double-tee bridge system prestressed with FRP materials.
Creator: Qiao, Pizhong., Florida Atlantic University, Arockiasamy, Madasamy, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The finite element analyses of the concrete bridge system and single double-tee beams are carried out using both orthotropic and isotropic modeling including linear and nonlinear behavior. The orthotropic concrete double-tee bridge system is modeled to predict the deformational behavior of bridge deck under the AASHTO service loading conditions in the static regimes. The nonlinear analyses of reinforced and prestressed concrete rectangular beams are also carried out to verify the validity of...
Show moreThe finite element analyses of the concrete bridge system and single double-tee beams are carried out using both orthotropic and isotropic modeling including linear and nonlinear behavior. The orthotropic concrete double-tee bridge system is modeled to predict the deformational behavior of bridge deck under the AASHTO service loading conditions in the static regimes. The nonlinear analyses of reinforced and prestressed concrete rectangular beams are also carried out to verify the validity of modeling. Both the linear and nonlinear finite element analyses for single double-tee beams prestressed with FRP materials are carried out in this study. In this research, the MARC finite element software on the VAX frame is used as a tool to carry out the analyses.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14936
Subject Headings: Finite element method, Fiber reinforced plastic, Bridges, Concrete--Floors, Prestressed concrete beams
Format: Document (PDF)

Title: Analyzing the effect of fin morphology on the propulsive performance of an oscillating caudal fin using a robotic model.
Creator: Fischer, Tyler M., Curet, Oscar M., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A bio-inspired robotic underwater vessel was developed to test the effect of fin morphology on the propulsive performance of caudal fin. The robotic vessel, called The Bullet Fish, features a cylindrical body with a hemisphere at the forward section and a conical body at the stern. The vessel uses an oscillating caudal fin for thrust generation. The robotic vessel was tested in a recirculating flume for seven different caudal fins that range different bio-inspired forms and aspect ratios. The...
Show moreA bio-inspired robotic underwater vessel was developed to test the effect of fin morphology on the propulsive performance of caudal fin. The robotic vessel, called The Bullet Fish, features a cylindrical body with a hemisphere at the forward section and a conical body at the stern. The vessel uses an oscillating caudal fin for thrust generation. The robotic vessel was tested in a recirculating flume for seven different caudal fins that range different bio-inspired forms and aspect ratios. The experiments were performed at four different flow velocities and two flapping frequencies: 0.5 and 1.0 Hz. We found that for 1 Hz flapping frequency that in general as the aspect-ratio decreases both thrust production tends and power decrease resulting in a better propulsive efficiency for aspect ratios between 0.9 and 1.0. A less uniform trend was found for 0.5 Hz, where our data suggest multiple efficiency peaks. Additional experiments on the robotic model could help understand the propulsion aquatic locomotion and help the design of bio-inspired underwater vehicles.
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Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00004944, http://purl.flvc.org/fau/fd/FA00004944
Subject Headings: Robotics., Robots--Kinematics., Artificial intelligence., Biomimetics., Bioinformatics., Stereotypes (Social psychology)
Format: Document (PDF)

Title: APPLICABILITY OF CATHODIC PROTECTION IN PREVENTION OF CORROSION DAMAGE TO STEEL TENDONS IN PRESTRESSED CONCRETE (HIGH STRENGTH STEEL, HYDROGEN EMBRITTLEMENT, BRITTLE CRACKING).
Creator: SCANNELL, WILLIAM THOMAS., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A series of experiments were performed on a single tendon in a prestressed concrete slab for the purpose of studying the susceptibility of the high strength steel to brittle fracture as a result of cathodic protection. The procedure first involved impressing an anodic current until active potentials were recorded along the tendon length. Subsequently, cathodic polarization of the midsection of the tendon to -1.3 V(SCE) was effected. After a prescribed time, the tendon was removed and...
Show moreA series of experiments were performed on a single tendon in a prestressed concrete slab for the purpose of studying the susceptibility of the high strength steel to brittle fracture as a result of cathodic protection. The procedure first involved impressing an anodic current until active potentials were recorded along the tendon length. Subsequently, cathodic polarization of the midsection of the tendon to -1.3 V(SCE) was effected. After a prescribed time, the tendon was removed and sectioned into 15 ern lengths. Each segment strand was then notched and strained to failure, in three-point bending, in order to determine any effect of cathodic protection on the mechanical properties of the material. Differences in average failure loads were compared to determine if a loss of load-bearing capacity and brittle fracture occurred due to hydrogen absorption.
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Date Issued: 1986
PURL: http://purl.flvc.org/fcla/dt/14324
Subject Headings: Prestressed concrete--Testing, Steel--Corrosion
Format: Document (PDF)

Title: APPLICATION OF A MICROPROCESSOR TO ACOUSTIC DATA SAMPLING AND MANAGEMENT TASKS (AS APPLIED TO MANGANESE NODULE MINING).
Creator: MURPHY, DAVID PAUL, JR., Florida Atlantic University, Davidson, J. Blaine, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Methods of collecting information about the deep ocean sediments are considered. A compact, flexible data collection and management system based on microprocessor technology is developed. The hardware of the system is detailed and a typical software operating system is presented which controls sensor operations, stores temporary data and communicates with a shipboard computer system.
Date Issued: 1979
PURL: http://purl.flvc.org/fcla/dt/13987
Subject Headings: Microprocessors, Marine sediments--Sampling, Manganese nodules
Format: Document (PDF)

Title: Application of G.I.S. for the stormwater drainage facilities, Village of Tequesta.
Creator: Rolley, Nathalie Anne-Claire., Florida Atlantic University, Scarlatos, Panagiotis (Pete) D., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The purpose of this study was to define the best Geographic Information System (G.I.S.) Software to manage the Storm Water Drainage Facilities for the Utilities Department of the Village of Tequesta, Florida. GeoMedia Professional was chosen, for its convenient user interface and its compatibility with other G.I.S. software such as ArcView or ARC/INFO. The GIS system displays the information in a map with different layers showing features such as drains or sewers. Subsystems were used to...
Show moreThe purpose of this study was to define the best Geographic Information System (G.I.S.) Software to manage the Storm Water Drainage Facilities for the Utilities Department of the Village of Tequesta, Florida. GeoMedia Professional was chosen, for its convenient user interface and its compatibility with other G.I.S. software such as ArcView or ARC/INFO. The GIS system displays the information in a map with different layers showing features such as drains or sewers. Subsystems were used to define the Levels of Standards (LOS) for the drainage system of the village. The data was collected from different sources such as Palm Beach County, or the property appraisers. The features are linked to databases, where the user can interface with the system and analyze the storm water network of the village. In the end, an interactive map was created with all the data, which provided a sufficient management tool for the Utilities Department.
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Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/12723
Subject Headings: Geographic information systems, Storm sewers--Florida--Tequesta
Format: Document (PDF)

Title: Application of MANOVA and Mahalanobis Distance in quality control.
Creator: Seth, Mahua., Florida Atlantic University, Mazouz, Abdel Kader, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Many quality control problems are multivariate in nature since multiple process or product variables are measured and monitored in modern industry. Occasionally a multiple population, multi-variable scenario is encountered in parallel line manufacturing system. This work deals with the analysis of such system using multivariate techniques such as Canonical Analysis, MANOVA and Mahalanobis Distance. Using such techniques, the significant differences between the populations and the magnitude...
Show moreMany quality control problems are multivariate in nature since multiple process or product variables are measured and monitored in modern industry. Occasionally a multiple population, multi-variable scenario is encountered in parallel line manufacturing system. This work deals with the analysis of such system using multivariate techniques such as Canonical Analysis, MANOVA and Mahalanobis Distance. Using such techniques, the significant differences between the populations and the magnitude and directions of the variations within and between the populations were determined. Also, elimination/reduction of such variations using multivariate techniques led to a drastic improvement of the production system. A methodology for application of such multivariate techniques for the purpose of quality assurance and improvement was developed here. The application of this methodology was performed on a pager production line and the results obtained show the benefits and the feasibility of the use of multivariate techniques for on-line monitoring and quality control.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15381
Subject Headings: Quality control, Beepers--Quality control, Process control
Format: Document (PDF)

Title: APPLICATION OF ORGAN-ON-A-CHIP TECHNOLOGY FOR MASS TRANSPORT ANALYSIS IN PHYSIOLOGICAL AND PATHOLOGICAL CONDITIONS.
Creator: Mosavati, Babak, Du, Sarah, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Mass transport is important for all biological functions to protect the cell’s environment and to keep its balance of nutrients, proteins and keep the organism alive. We are motivated to study two different types of mass transport, glucose and oxygen that are critical in human system. Specifically, this study focused on mass and oxygen transport in human placenta and oxygen transport in transfusion of artificial oxygen carriers. Studying these processes in vivo or ex vivo are difficult due to...
Show moreMass transport is important for all biological functions to protect the cell’s environment and to keep its balance of nutrients, proteins and keep the organism alive. We are motivated to study two different types of mass transport, glucose and oxygen that are critical in human system. Specifically, this study focused on mass and oxygen transport in human placenta and oxygen transport in transfusion of artificial oxygen carriers. Studying these processes in vivo or ex vivo are difficult due to ethical or technical challenges. In this dissertation, Organ-on-a-chip devices were used to simulate placental barrier and blood vessels. In first device, 3D placenta–on-a-chip device consists of a polycarbonate membrane and two Poly dimethylsiloxane microchannels was used. Human umbilical vein endothelial cells were cultured in microfluidic devices and mass transport was measured. In the second device, 3-lane OrganoPlate was used to develop the placental barrier model. The human umbilical vein endothelial cells and trophoblast cells cultured in two microchannels compartmented by polycarbonate membrane (first device) and extracellular matrix gel (second device) to mimic the placental barrier in vitro. Finally, the glucose transfer across the placental barrier affected by malaria parasite was investigated. The results of this study can be used for better understanding of placental malaria pathology and drug efficacy testing.
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Date Issued: 2022
PURL: http://purl.flvc.org/fau/fd/FA00013963
Subject Headings: Organs-on-chips, Biomedical engineering
Format: Document (PDF)

Title: An application of perturbation techniques to the vibration analysis of structures with viscoelastic coating modifications.
Creator: Kelly, William Joseph, Jr., Florida Atlantic University, Stevens, Karl K., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Proper application of matrix perturbation theory to the structural modification of vibrating systems yields accurate results without resolving the eigenvalue problem. For this reason it seems that the method may require less computer time and cost in performing iterative type design work. This thesis investigates the application of first-order perturbation techniques to a torsional shaft system subject to viscoelastic damping treatment modifications. The modifications are of general form in...
Show moreProper application of matrix perturbation theory to the structural modification of vibrating systems yields accurate results without resolving the eigenvalue problem. For this reason it seems that the method may require less computer time and cost in performing iterative type design work. This thesis investigates the application of first-order perturbation techniques to a torsional shaft system subject to viscoelastic damping treatment modifications. The modifications are of general form in that the coating length and thickness are not restricted. Large modifications are built up by a series of small first-order perturbations. In addition to developing a better understanding of the usefulness of this application of perturbation theory, the goal of this paper is also to understand the nonproportional damping effects of partial viscoelastic coatings.
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Date Issued: 1988
PURL: http://purl.flvc.org/fcla/dt/14455
Subject Headings: Vibration, Perturbation (Mathematics)
Format: Document (PDF)

Title: Application of probabilistic analogy to groundwater contamination problems.
Creator: Qiu, Xin., Florida Atlantic University, Su, Tsung-Chow, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This thesis addresses the groundwater contamination problem from a probabilistic point of view. The objective of this study is to obtain analytical solutions for the backward type Kolmogorov equations governing certain crucial variables in the case of a two-dimensional medium. These include the rate at which pollutants enter the protected zone and the length of time that a pollutant particle takes to travel from a given location to the boundary of the protected zone. It is assumed that the...
Show moreThis thesis addresses the groundwater contamination problem from a probabilistic point of view. The objective of this study is to obtain analytical solutions for the backward type Kolmogorov equations governing certain crucial variables in the case of a two-dimensional medium. These include the rate at which pollutants enter the protected zone and the length of time that a pollutant particle takes to travel from a given location to the boundary of the protected zone. It is assumed that the groundwater flow is horizontal and uniform, and that a protected zone is located downstream. Analytical solutions are obtained by using the techniques of Laplace transform and separation of variables. Numerical results are given for two cases, one with flow coming from a boundary which is imperious to the pollutant, and another with flow coming from infinity.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14980
Subject Headings: Groundwater--Pollution--Mathematical models, Groundwater flow--Mathematical models, Pollutants
Format: Document (PDF)

Title: Application of relational database to computer-aided process planning.
Creator: Tulpule, Rajiv S., Florida Atlantic University, Han, Chingping (Jim), College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The present trend in manufacturing technology indicates strong tendencies to integrate computer aided design (CAD) and computer aided manufacturing (CAM) to attain the computer integrated manufacturing (CIM) system. Computer aided process planning (CAPP) system serves as the key linkage that interfaces CAD and CAM. In this research, a CAPP system, namely, RD-CAPP was developed using the variant process planning approach. This system is used to generate process plans automatically. The RD-CAPP...
Show moreThe present trend in manufacturing technology indicates strong tendencies to integrate computer aided design (CAD) and computer aided manufacturing (CAM) to attain the computer integrated manufacturing (CIM) system. Computer aided process planning (CAPP) system serves as the key linkage that interfaces CAD and CAM. In this research, a CAPP system, namely, RD-CAPP was developed using the variant process planning approach. This system is used to generate process plans automatically. The RD-CAPP system developed during this research uses group technology (GT) concepts and a relational data model. The application of the relational database management system and GT provides various advantages such as ease of information management, ease of modification and updating of information stored, ease of interlinking of various databases, etc. The effectiveness of the system described has been verified through the use of industrial data. The results of the study along with the development of various modules and the computer programs are discussed in this thesis.
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Date Issued: 1989
PURL: http://purl.flvc.org/fcla/dt/14550
Subject Headings: Computer-aided design, CAD/CAM systems, Engineering design--Data processing
Format: Document (PDF)

Title: APPLICATION OF SIGNAL DECOMPOSITION TO IMPROVE TIME DELAY ESTIMATES FOR SYNTHETIC APERTURE SONAR MOTION COMPENSATION.
Creator: Gazagnaire, Julia, Beaujean, Pierre-Philippe, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Synthetic Aperture Sonar (SAS) provides the best opportunity for side-looking sonar mounted on underwater platforms to achieve high-resolution images. However, SAS processing requires strict constraints on resolvable platform motion. The most common approach to estimate this motion is to use the Redundant Phase Center (RPC) technique. Here the ping interval is set, such that a portion of the sonar array overlaps as the sensor moves forward. The time delay between the pings received on these...
Show moreSynthetic Aperture Sonar (SAS) provides the best opportunity for side-looking sonar mounted on underwater platforms to achieve high-resolution images. However, SAS processing requires strict constraints on resolvable platform motion. The most common approach to estimate this motion is to use the Redundant Phase Center (RPC) technique. Here the ping interval is set, such that a portion of the sonar array overlaps as the sensor moves forward. The time delay between the pings received on these overlapping elements is estimated using cross-correlation. These time delays are then used to infer the pingto-ping vehicle motion. Given the stochastic nature of the operational environment, some level of decorrelation between these two signals is likely. In this research, two iterative signal decomposition methods well suited for nonlinear and non-stationary signals, are investigated for their potential to improve the Time Delay Estimation (TDE). The first of this type, the Empirical Mode Decomposition (EMD) was introduced by Huang in the seminal paper, The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis and is the foundation for the algorithms used in this research. This method decomposes a signal into a finite sequence of simple components termed Intrinsic Mode Functions (IMFs). The Iterative Filter (IF) approach, developed by Lin, Wang and Zhou, builds on the EMD framework. The sonar signals considered in this research are complex baseband signals. Both the IF and EMD algorithms were designed to decompose real signals. However, the IF variant, the Multivariate Fast Iterative Filtering (MFIF) Algorithm, developed by Cicone, and the EMD variant, the Fast and Adaptive Multivariate Empirical Mode Decomposition (FAMVEMD) algorithm, developed by Thirumalaisamy and Ansell, preserve both the magnitude and phase in the decomposition and hence were chosen for this analysis.
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Date Issued: 2021
PURL: http://purl.flvc.org/fau/fd/FA00013795
Subject Headings: Sonar, Signal processing, Synthetic apertures
Format: Document (PDF)

Title: THE APPLICATION OF THE ENERGY ACCOUNTANCY EQUATION IN THE INVESTIGATION OF ENERGY TRANSFER IN A THIN WALLED SHELL STRUCTURE.
Creator: SCHAPLEY, RAMON FRANK, II., Florida Atlantic University, Dunn, Stanley E., Cuschieri, Joseph M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The Energy Accountancy method is used to describe the response of a system by accounting for the various energy components in a system, that is components describing the input energy, the energy dissipated, and the energy transfered by the system. These components are functions of quantities that can be determined either through measurement or finite element analysis of the system. This concept is used in this study to determine the response of a small diameter pipe containing two different...
Show moreThe Energy Accountancy method is used to describe the response of a system by accounting for the various energy components in a system, that is components describing the input energy, the energy dissipated, and the energy transfered by the system. These components are functions of quantities that can be determined either through measurement or finite element analysis of the system. This concept is used in this study to determine the response of a small diameter pipe containing two different fluids, air and water. The results of this study have shown that the Snergy Accountancy method can be used to describe the response of a thin walled shell structure with good results. It has also been shown in this study that in small diameter pipes the fluid contained by the system can be considered to act as a reactive medium in the response of the structure.
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Date Issued: 1985
PURL: http://purl.flvc.org/fcla/dt/14277
Subject Headings: Force and energy--Analysis, Force and energy--Measurement
Format: Document (PDF)

Title: APPLICATIONS OF DIGITAL HOLOGRAPHIC IMAGING TOWARDS CHARACTERIZATION OF MARINE PLANKTON DISTRIBUTIONS AND BIOPHYSICAL INTERACTIONS.
Creator: Barua, Ranjoy, Nayak, Aditya R., Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: Characterization of the distribution and biophysical interactions of oceanic planktonic organisms is crucial to address fundamental science questions associated with climate change, marine ecology, pollution, and ocean optics. Thus, development of instrumentation techniques for monitoring plankton at high spatial and temporal resolutions is important. This dissertation deals with the advancements made in applying digital holography – a 3-D non-intrusive, freestream imaging technique – to...
Show moreCharacterization of the distribution and biophysical interactions of oceanic planktonic organisms is crucial to address fundamental science questions associated with climate change, marine ecology, pollution, and ocean optics. Thus, development of instrumentation techniques for monitoring plankton at high spatial and temporal resolutions is important. This dissertation deals with the advancements made in applying digital holography – a 3-D non-intrusive, freestream imaging technique – to address three different applications associated with marine plankton monitoring and ecology. In the first project, an autonomous in-line digital holographic microscope was successfully deployed for rapid in situ detection of the harmful dinoflagellate, Karenia brevis in the coastal Gulf of Mexico. Monitoring K. brevis abundance and distribution are crucial for early warning systems and implementing preventative measures to limit potential damage. The holographic system was successfully paired with a convolutional neural network for automated data processing to ensure rapid and accurate K. brevis detection.
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Date Issued: 2022
PURL: http://purl.flvc.org/fau/fd/FA00014096
Subject Headings: Marine plankton, Holography, Digital holographic microscopy
Format: Document (PDF)

Title: Applications of evolutionary algorithms in mechanical engineering.
Creator: Nelson, Kevin M., Florida Atlantic University, Huang, Ming Z., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Many complex engineering designs have conflicting requirements that must be compromised to effect a successful product. Traditionally, the engineering approach breaks up the complex problem into smaller sub-components in known areas of study. Tradeoffs occur between the conflicting requirements and a sub-optimal design results. A new computational approach based on the evolutionary processes observed in nature is explored in this dissertation. Evolutionary algorithms provide methods to solve...
Show moreMany complex engineering designs have conflicting requirements that must be compromised to effect a successful product. Traditionally, the engineering approach breaks up the complex problem into smaller sub-components in known areas of study. Tradeoffs occur between the conflicting requirements and a sub-optimal design results. A new computational approach based on the evolutionary processes observed in nature is explored in this dissertation. Evolutionary algorithms provide methods to solve complex engineering problems by optimizing the entire system, rather than sub-components of the system. Three standard forms of evolutionary algorithms have been developed: evolutionary programming, genetic algorithms and evolution strategies. Mathematical and algorithmic details are described for each of these methods. In this dissertation, four engineering problems are explored using evolutionary programming and genetic algorithms. Exploiting the inherently parallel nature of evolution, a parallel version of evolutionary programming is developed and implemented on the MasPar MP-1. This parallel version is compared to a serial version of the same algorithm in the solution of a trial set of unimodal and multi-modal functions. The parallel version had significantly improved performance over the serial version of evolutionary programming. An evolutionary programming algorithm is developed for the solution of electronic part placement problems with different assembly devices. The results are compared with previously published results for genetic algorithms and show that evolutionary programming can successfully solve this class of problem using fewer genetic operators. The finite element problem is cast into an optimization problem and an evolutionary programming algorithm is developed to solve 2-D truss problems. A comparison to LU-decomposition showed that evolutionary programming can solve these problems and that it has the capability to solve the more complex nonlinear problems. Finally, ordinary differential equations are discretized using finite difference representation and an objective function is formulated for the application of evolutionary programming and genetic algorithms. Evolutionary programming and genetic algorithms have the benefit of permitting over-constraining a problem to obtain a successful solution. In all of these engineering problems, evolutionary algorithms have been shown to offer a new solution method.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/12514
Subject Headings: Mechanical engineering, Genetic algorithms, Evolutionary programming (Computer science)
Format: Document (PDF)

Title: APPLYING BLIND SOURCE SEPARATION TO MAGNETIC ANOMALY DETECTION.
Creator: Nieves, Eric, Beaujean, Pierre-Philippe, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description: The research shows a novel approach for the Magnetic Anomaly Differentiation and Localization Algorithm, which simultaneously localizes multiple magnetic anomalies with weak total field signatures (tens of nT). In particular, it focuses on the case where there are two homogeneous targets with known magnetic moments. This was done by analyzing the magnetic signals and adapting Independent Component Analysis (ICA) and Simulated Annealing (SA) to solve the problem statement. The results show the...
Show moreThe research shows a novel approach for the Magnetic Anomaly Differentiation and Localization Algorithm, which simultaneously localizes multiple magnetic anomalies with weak total field signatures (tens of nT). In particular, it focuses on the case where there are two homogeneous targets with known magnetic moments. This was done by analyzing the magnetic signals and adapting Independent Component Analysis (ICA) and Simulated Annealing (SA) to solve the problem statement. The results show the groundwork for using a combination of fastICA and SA to give localization errors of 3 meters or less per target in simulation and achieved a 58% success rate. Experimental results experienced additional errors due to the effects of magnetic background, unknown magnetic moments, and navigation error. While one target was localized within 3 meters, only the latest experimental run showed the second target approaching the localization specification. This highlighted the need for higher signal-to-noise ratio and equipment with better navigational accuracy. The data analysis was used to provide recommendations on the needed equipment to minimize observed errors and improve algorithm success.
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Date Issued: 2020
PURL: http://purl.flvc.org/fau/fd/FA00013610
Subject Headings: Magnetic anomalies, Simulated annealing (Mathematics), Independent component analysis, Unmanned vehicles
Format: Document (PDF)

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