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 Title
 Methodology for fault detection and diagnostics in an ocean turbine using vibration analysis and modeling.
 Creator
 Mjit, Mustapha., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

This thesis describes a methodology for mechanical fault detection and diagnostics in an ocean turbine using vibration analysis and modeling. This methodology relies on the use of advanced methods for machine vibration analysis and health monitoring. Because of some issues encountered with traditional methods such as Fourier analysis for non stationary rotating machines, the use of more advanced methods such as TimeFrequency Analysis is required. The thesis also includes the development of...
Show moreThis thesis describes a methodology for mechanical fault detection and diagnostics in an ocean turbine using vibration analysis and modeling. This methodology relies on the use of advanced methods for machine vibration analysis and health monitoring. Because of some issues encountered with traditional methods such as Fourier analysis for non stationary rotating machines, the use of more advanced methods such as TimeFrequency Analysis is required. The thesis also includes the development of two LabVIEW models. The first model combines the advanced methods for online condition monitoring. The second model performs the modal analysis to find the resonance frequencies of the subsystems of the turbine. The dynamic modeling of the turbine using Finite Element Analysis is used to estimate the baseline of vibration signals in sensors locations under normal operating conditions of the turbine. All this information is necessary to perform the vibration condition monitoring of the turbine.
Show less  Date Issued
 2009
 PURL
 http://purl.flvc.org/FAU/369198
 Subject Headings
 Marine turbines, Mathematical models, Fluid dynamics, Structural dynamics, Composite materials, Mathematical models, Elastic analysis (Engineering)
 Format
 Document (PDF)
 Title
 Application of probabilistic analogy to groundwater contamination problems.
 Creator
 Qiu, Xin., Florida Atlantic University, Su, TsungChow, 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 twodimensional 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 twodimensional 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.
Show less  Date Issued
 1993
 PURL
 http://purl.flvc.org/fcla/dt/14980
 Subject Headings
 GroundwaterPollutionMathematical models, Groundwater flowMathematical models, Pollutants
 Format
 Document (PDF)
 Title
 AN ECONOMETRIC MODEL OF FLORIDA'S GOLD COAST.
 Creator
 BUCCA, JANE KIRKER., Florida Atlantic University, Stronge, William B., College of Business, Department of Economics
 Abstract/Description

This thesis deals with regional econometric models. The first chapter discusses static economic modeling. Chapter Two deals with models of substate regional economics. The third chapter presents an econometric model of Florida's Gold Coast including dynamic analysis of short and long run adjustment.
 Date Issued
 1981
 PURL
 http://purl.flvc.org/fcla/dt/14049
 Subject Headings
 EconomicsFloridaMathematical models, FloridaEconomic conditionsMathematical models
 Format
 Document (PDF)
 Title
 Development and implementation of integrated acoustic and oceanographic numerical modeling in coastal regions.
 Creator
 Walker, Natasha Maria., Florida Atlantic University, Glegg, Stewart A. L., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

An integrated coastal ocean and acoustic propagation model has been implemented to determine the effects of the ocean variations on the acoustic propagation field applied specifically to SFOMC. The ocean dynamics were modeled using the sigma coordinate, orthogonal curvilinear grid, Princeton Ocean Model. By using forcing conditions of tide, river runoff, wind and realistic bottom topography, the resulting time variant regional sound velocity outputs from the model were used as inputs to the...
Show moreAn integrated coastal ocean and acoustic propagation model has been implemented to determine the effects of the ocean variations on the acoustic propagation field applied specifically to SFOMC. The ocean dynamics were modeled using the sigma coordinate, orthogonal curvilinear grid, Princeton Ocean Model. By using forcing conditions of tide, river runoff, wind and realistic bottom topography, the resulting time variant regional sound velocity outputs from the model were used as inputs to the range dependent, parabolic equation, acoustic propagation model, RAM. The results show that the fluctuations in the ocean result in scintillation in the acoustic propagation field, and for higher frequencies this variability is uniformly distributed and at times as much as +/3 dB. High resolution in the POM grid and the range and depth sizes for RAM were important for obtaining reliable simulation results.
Show less  Date Issued
 2002
 PURL
 http://purl.flvc.org/fcla/dt/12901
 Subject Headings
 OceanographyMathematical models, Underwater acousticsMathematical models, Coastal engineering
 Format
 Document (PDF)
 Title
 Convex identification and nonlinear random vibration analysis of elastic and viscoelastic structures.
 Creator
 Fang, Jianjie, Florida Atlantic University, Elishakoff, Isaac, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

This dissertation deals with the identification of boundary conditions of elastic structures, and nonlinear random vibration analysis of elastic and viscoelastic structures through a new energybased equivalent linearization technique. In the part of convex identification, convex models are utilized to represent the degree of uncertainty in the boundary condition modification. This means that the identification is actually the identification of the convex model to which the actual boundary...
Show moreThis dissertation deals with the identification of boundary conditions of elastic structures, and nonlinear random vibration analysis of elastic and viscoelastic structures through a new energybased equivalent linearization technique. In the part of convex identification, convex models are utilized to represent the degree of uncertainty in the boundary condition modification. This means that the identification is actually the identification of the convex model to which the actual boundary stiffness profile belongs. Two examples are presented to illustrate the application of the method. For the beam example the finite element analysis is performed to evaluate the frequencies of a beam with any specific boundary conditions. For the plate example, the Bolotin's dynamic edge effect method, generalized by Elishakoff, is employed to determine the approximate natural frequencies and normal modes of elastically supported isotropic, uniform rectangular plates. In the part of nonlinear random analysis, first a systematic finite element analysis procedure, based on the element's energy formulation, through conventional stochastic linearization technique, is proposed. The procedure is applicable to a wide range of nonlinear random vibration problem as long as element's energy formulations are presented. Secondly, the new energybased stochastic linearization method in finite element analysis setting is developed to improve the conventional stochastic linearization technique. The entire formulation is produced in detail for the first time. The theory is applied to beam problem subjected to spacewise and timewise white noise excitations. Finally, the new energybased stochastic linearization technique is applied to treat nonlinear vibration problems of viscoelastic beams.
Show less  Date Issued
 1996
 PURL
 http://purl.flvc.org/fcla/dt/12467
 Subject Headings
 Elasticity, Viscoelasticity, Structural dynamicsMathematical models, VibrationMathematical models
 Format
 Document (PDF)
 Title
 Performance analysis of linear diversity schemes in generalized gamma fading channels.
 Creator
 Piboongungon, Terawat., Florida Atlantic University, Aalo, Valentine A., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

The main focus of this dissertation is to analyze the performance of linear diversity schemes operating in generalized gamma fading channels. The generalized gamma fading model is a versatile fading envelope that generalizes many of commonly used statistical models that describe signal fluctuations due to multipath, shadowing, or a mixture of such processes. The traditional linear diversity combining techniques such as maximal ratio combining (MRC), equal gain combining (EGC), and selection...
Show moreThe main focus of this dissertation is to analyze the performance of linear diversity schemes operating in generalized gamma fading channels. The generalized gamma fading model is a versatile fading envelope that generalizes many of commonly used statistical models that describe signal fluctuations due to multipath, shadowing, or a mixture of such processes. The traditional linear diversity combining techniques such as maximal ratio combining (MRC), equal gain combining (EGC), and selection combining (SC) are addressed with reference to generalized gamma fading environments. For the special case of Nakagami fading, new expressions for outage probability and errorrate performance of linear diversity schemes with arbitrary fading parameters are derived in terms of the Lauricella function. Effects of correlated fading are also studied. Their fruitful application to third generation (3G) wideband code division multiple access (WCDMA) systems, particularly for multipleinput multipleoutput (MIMO) and 2DRAKE receivers are demonstrated. The results exhibit a finite integral representation that can be used for fast and accurate numerical computation. A detail study is also done on multivariate generalized gamma fading environments. Relevant statistical characterization of the sum of independent generalized gamma random variables is derived and expressed in terms of the multivariable Fox's Hfunction. Since numerical evaluation for the multivariate Fox's Hfunction is difficult, simpler numerical computations are developed using moment generating function and characteristic function approaches. Since some wireless applications may not have enough space among diversity branches, the statistical characterizations of multivariate correlated generalized gamma fading are relevant in such cases. An investigation on the outage performance for multibranch selection combining is performed for the correlated multivariate generalized gamma channel. Finally, the dissertation summarizes the main results and explores some directions for further studies.
Show less  Date Issued
 2005
 PURL
 http://purl.flvc.org/fcla/dt/12135
 Subject Headings
 Numerical integration, Wireless communication systemsMathematical models, Frequency spectraMathematical models
 Format
 Document (PDF)
 Title
 Numerical simulations of the wave bottom boundary layer over sand ripples.
 Creator
 Pierro, Thomas P., Florida Atlantic University, Slinn, D. N., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

Surface gravity waves propagating in the nearshore produce an oscillatory freestream potential flow near the seabed and commonly cause regular twodimensional sand ripples to be formed. The existence of the ripples causes complex turbulent flows to evolve in the boundary layer, which can dissipate significant energy from the surface waves. A timedependent DNS model is used to solve the NavierStokes equations in three dimensions on a transformed curvilinear grid for specified wave parameters...
Show moreSurface gravity waves propagating in the nearshore produce an oscillatory freestream potential flow near the seabed and commonly cause regular twodimensional sand ripples to be formed. The existence of the ripples causes complex turbulent flows to evolve in the boundary layer, which can dissipate significant energy from the surface waves. A timedependent DNS model is used to solve the NavierStokes equations in three dimensions on a transformed curvilinear grid for specified wave parameters. When compared to smooth beds, simulations over wavy topographies demonstrate that turbulence is enhanced due to flow separation in the lee of the ripple crests. Shear instabilities during phases of weak flow and vortex shedding in times of strong flow work together to sustain turbulence throughout the wave period. Resulting flows over ripples exhibit an increase in boundary layer thickness and dissipation rates, as energy is lost to viscous effects in maintaining turbulence.
Show less  Date Issued
 2001
 PURL
 http://purl.flvc.org/fcla/dt/12854
 Subject Headings
 Boundary layerMathematical models, WavesMathematical models, Sand waves
 Format
 Document (PDF)
 Title
 Mathematical modeling of the pit initiation process.
 Creator
 Kappukattil, Lizamma Joseph., Florida Atlantic University, Lee, Rupert U., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

The potential at which pitting corrosion begins under anodic polarization is a function of the environmental parameters. Determination of this characteristic potential enables prediction of pitting susceptibility under specific environmental conditions. The pitting potentials were determined experimentally for AISI 304 stainless steel for different values of chloride ion concentration, sulphate ion concentration, temperature and solution pH. A factorial design technique was employed to study...
Show moreThe potential at which pitting corrosion begins under anodic polarization is a function of the environmental parameters. Determination of this characteristic potential enables prediction of pitting susceptibility under specific environmental conditions. The pitting potentials were determined experimentally for AISI 304 stainless steel for different values of chloride ion concentration, sulphate ion concentration, temperature and solution pH. A factorial design technique was employed to study the individual and interaction effects of parameters in order to investigate the multifaceted nature of the pitting process. An empirical model was developed based on the result of the factorial analysis. The model emphasizes the fact that the pit nucleation process involves interrelated processes, and that the parameters behave differently with respect to each process.
Show less  Date Issued
 1989
 PURL
 http://purl.flvc.org/fcla/dt/14548
 Subject Headings
 Corrosion and anticorrosivesMathematical models, MetalsCorrosion fatigueMathematical models
 Format
 Document (PDF)
 Title
 Subsurface flow generated by a steady wind stress applied at the water surface.
 Creator
 Gurfinkiel, Lionel., Florida Atlantic University, Dhanak, Manhar R.
 Abstract/Description

A turbulent water current induced by winds, through a friction force at the sea surface and subjected to the Coriolis force in shallow water was studied. A Large Eddy Simulation model developed by Zikanov et al. is used to solve the NavierStokes equations. To define the bottom boundary condition, a drag coefficient parameter, based on the ideas of Csanady, is used to evaluate the shear stress at the bottom. To find a suitable bottom boundary condition for this LES simulation, several cases...
Show moreA turbulent water current induced by winds, through a friction force at the sea surface and subjected to the Coriolis force in shallow water was studied. A Large Eddy Simulation model developed by Zikanov et al. is used to solve the NavierStokes equations. To define the bottom boundary condition, a drag coefficient parameter, based on the ideas of Csanady, is used to evaluate the shear stress at the bottom. To find a suitable bottom boundary condition for this LES simulation, several cases were considered with change in drag coefficient property. The effect of variation in the depth of the water column was also considered. Variation in surface deflection of the current, variation of the mass flux and distribution of eddy viscosity with depth of the water column are determined. The cases are compared with the case of a deep water column. Numerical results are also compared with field observations.
Show less  Date Issued
 2003
 PURL
 http://purl.flvc.org/fcla/dt/13030
 Subject Headings
 Oceanatmosphere interactionMathematical models, Turbulence, Wind wavesMathematical models
 Format
 Document (PDF)
 Title
 Timedependent multipath modeling for underwater acoustic wave propagation in shallow water.
 Creator
 Boulanger, Florent Jacques., Florida Atlantic University, Beaujean, PierrePhilippe
 Abstract/Description

A novel acoustic wave propagation model has been developed to determine the effects of the ocean variations on the acoustic propagation field, and to determine the signal measured by a receiver at any distance from an omnidirectional source. The model accounts for environmental conditions. First, a stationary estimate of the complex sound attenuation is computed as a function of frequency and location, using the parabolic equation numerical technique. For a given range, the vertical profile...
Show moreA novel acoustic wave propagation model has been developed to determine the effects of the ocean variations on the acoustic propagation field, and to determine the signal measured by a receiver at any distance from an omnidirectional source. The model accounts for environmental conditions. First, a stationary estimate of the complex sound attenuation is computed as a function of frequency and location, using the parabolic equation numerical technique. For a given range, the vertical profile of the attenuation frequency spectrum is decomposed in the wave number domain. A specific Doppler shift is associated with each wave number. The spacefrequency attenuation filter obtained is applied to the transmitted signal to create timefrequency selective fading. This model has been used to simulate the performance of the General Purpose Acoustic Modem, which transmits MFSK modulated sequences between 15.6 kHz to 32.1 kHz. The range of operation varies from 1 to 5 km, in 15 meters of water. Experimental data have been collected under seastate 2 conditions. The model has been successfully validated when compared to experimental data and to the Crepeau model.
Show less  Date Issued
 2003
 PURL
 http://purl.flvc.org/fcla/dt/12978
 Subject Headings
 Underwater acousticsMathematical models, SoundTransmission, Ocean wavesMathematical models
 Format
 Document (PDF)
 Title
 Statistical modeling of the container inventory control in a distribution network.
 Creator
 Feng, Weiming., Florida Atlantic University, Han, Chingping (Jim), College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

The study of the reusable container inventory control in a distribution network is crucial to the efficiency and cost effectiveness of the transportation systems. In order to minimize the total operation cost of such a transportation network system, all subsystems of the distribution network have to be optimized together as a whole system. In this study, we extended the inventory control concept and developed a multipleinventory control model for the transportation network. We presented a...
Show moreThe study of the reusable container inventory control in a distribution network is crucial to the efficiency and cost effectiveness of the transportation systems. In order to minimize the total operation cost of such a transportation network system, all subsystems of the distribution network have to be optimized together as a whole system. In this study, we extended the inventory control concept and developed a multipleinventory control model for the transportation network. We presented a systematic approach to address all those subsystems as interrelated systems. Mathematical models were developed for the transportation and container inventory control problems first. Then, the statistical modeling method was used to analyze the effects of the container inventory management policies on the performance of the transportation system. Based on the optimization theory, simulation executions were such arranged to lead to the globe optimality. This makes it possible to optimize the variables of inventory control under different control policies without solving mathematical models. A Simulation Code Generator (SCG) was also developed for a general container inventory control system.
Show less  Date Issued
 1997
 PURL
 http://purl.flvc.org/fcla/dt/12525
 Subject Headings
 Inventory controlMathematical models, Containerization, TransportationMathematical models, Inventory controlSimulation methods
 Format
 Document (PDF)
 Title
 Simulation study on option pricing under jump diffusion models.
 Creator
 Rodrigues, Justin, Long, Hongwei, Charles E. Schmidt College of Science, Department of Mathematical Sciences
 Abstract/Description

The main objective of this thesis is to simulate, evaluate and discuss several methods for pricing Europeanstyle options. The BlackScholes model has long been considered the standard method for pricing options. One of the downfalls of the BlackScholes model is that it is strictly continuous and does not incorporate discrete jumps. This thesis will consider two alternate Levy models that include discretized jumps; The Merton Jump Diffusion and Kou's Double Exponential Jump Diffusion. We...
Show moreThe main objective of this thesis is to simulate, evaluate and discuss several methods for pricing Europeanstyle options. The BlackScholes model has long been considered the standard method for pricing options. One of the downfalls of the BlackScholes model is that it is strictly continuous and does not incorporate discrete jumps. This thesis will consider two alternate Levy models that include discretized jumps; The Merton Jump Diffusion and Kou's Double Exponential Jump Diffusion. We will use each of the three models to price real world stock data through software simulations and explore the results.Keywords: Levy Processes, Brownian motion, Option pricing, Simulation, BlackScholes, Merton Jump Diffusion, Kou, Kou's Double Exponential Jump Diffusion.
Show less  Date Issued
 2013
 PURL
 http://purl.flvc.org/fau/fd/FA0004051
 Subject Headings
 Finance  Mathematical models, Levy processes, Prices  Econometric models, Statistical physics, Stochastic processes, Valuation  Econometric models
 Format
 Document (PDF)
 Title
 MODFLOW wetland module which relates interactions with aquifers and sloughs.
 Creator
 Montoya, Angela M., Florida Atlantic University, Restrepo, Jorge I.
 Abstract/Description

Natural and anthropogenic processes have altered wetland habitats. The simulation of surface water movement and its interaction with groundwater and slough channels as it relates to wetlands is very important for many projects. Currently, most groundwater flow models incorporate the wetland system as general head boundary nodes. The purpose of this research was to develop a computer package for the widely used MODFLOW code to simulate threedimensional wetland flow hydroperiods interacting...
Show moreNatural and anthropogenic processes have altered wetland habitats. The simulation of surface water movement and its interaction with groundwater and slough channels as it relates to wetlands is very important for many projects. Currently, most groundwater flow models incorporate the wetland system as general head boundary nodes. The purpose of this research was to develop a computer package for the widely used MODFLOW code to simulate threedimensional wetland flow hydroperiods interacting with aquifers and slough channels. The groundwater flow model was used to reproduce surface water flow process through wetlands, estimating new flow rates and values using a Manning type of equation. This package represents flow routing, the export/import of water, and the evapotranspiration from wetlands during different hydroperiods. The verification procedure for the numerical solution was based on a testcase that was solved using a twodimensional surface water model. This testcase example is a transient solution to the diffusion equation starting with initial conditions depicted by a sinusoidal water surface profile and a flat bottom.
Show less  Date Issued
 1997
 PURL
 http://purl.flvc.org/fcla/dt/15440
 Subject Headings
 Groundwater flowModels, WetlandsMathematical models, Aquifers, Hydrologic models
 Format
 Document (PDF)
 Title
 Migration induced epidemics: dynamics of fluxbased multipatch models.
 Creator
 Liebovitch, Larry S., Schwartz, Ira B.
 Date Issued
 2004
 PURL
 http://purl.flvc.org/FAU/165227
 Subject Headings
 Communicable diseasesEpidemiologyMathematical models, Emerging infectious diseases, Epidemiologic Methods, Epidemiology, Biomathematics, MedicineMathematics, DynamicsMathematical models
 Format
 Document (PDF)
 Title
 Dynamical response of multipatch, fluxbased models to the input of infected people: epidemic response to initiated events.
 Creator
 Liebovitch, Larry S., Schwartz, Ira B., Rho, YoungAh
 Date Issued
 20080721
 PURL
 http://purl.flvc.org/FAU/165229
 Subject Headings
 Communicable diseasesEpidemiologyMathematical models, Epidemiologic Methods, Differential equations, DynamicsMathematical models, Spatial systemsMathematical models, Population dynamics, Emerging infectious diseases
 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
 TurbulenceMathematical models., Marine turbinesMathematical models., Wind turbinesAerodynamicsMathematical models., Structural dynamics., Computational fluid dynamics., Fluid dynamic measurements., Atmospheric circulation.
 Format
 Document (PDF)
 Title
 Data gateway for prognostic health monitoring of oceanbased power generation.
 Creator
 Gundel, Joseph., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

On August 5, 2010 the U.S. Department of Energy (DOE) has designated the Center for Ocean Energy Technology (COET) at Florida Atlantic University (FAU) as a national center for ocean energy research and development. Their focus is the research and development of openocean current systems and associated infrastructure needed to development and testing prototypes. The generation of power is achieved by using a specialized electric generator with a rotor called a turbine. As with all machines,...
Show moreOn August 5, 2010 the U.S. Department of Energy (DOE) has designated the Center for Ocean Energy Technology (COET) at Florida Atlantic University (FAU) as a national center for ocean energy research and development. Their focus is the research and development of openocean current systems and associated infrastructure needed to development and testing prototypes. The generation of power is achieved by using a specialized electric generator with a rotor called a turbine. As with all machines, the turbines will need maintenance and replacement as they near the end of their lifecycle. This prognostic health monitoring (PHM) requires data to be collected, stored, and analyzed in order to maximize the lifespan, reduce downtime and predict when failure is eminent. This thesis explores the use of a data gateway which will separate high level software with low level hardware including sensors and actuators. The gateway will v standardize and store the data collected from various sensors with different speeds, formats, and interfaces allowing an easy and uniform transition to a database system for analysis.
Show less  Date Issued
 2012
 PURL
 http://purl.flvc.org/FAU/3342111
 Subject Headings
 Machinery, Monitoring, Marine turbines, Mathematical models, Fluid dynamics, Structural dynamics
 Format
 Document (PDF)
 Title
 Detection, localization, and identification of bearings with raceway defect for a dynamometer using high frequency modal analysis of vibration across an array of accelerometers.
 Creator
 Waters, Nicholas., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

This thesis describes a method to detect, localize and identify a faulty bearing in a rotating machine using narrow band envelope analysis across an array of accelerometers. This technique is developed as part of the machine monitoring system of an ocean turbine. A rudimentary mathematical model is introduced to provide an understanding of the physics governing the vibrations caused by a bearing with a raceway defect. This method is then used to detect a faulty bearing in two setups : on a...
Show moreThis thesis describes a method to detect, localize and identify a faulty bearing in a rotating machine using narrow band envelope analysis across an array of accelerometers. This technique is developed as part of the machine monitoring system of an ocean turbine. A rudimentary mathematical model is introduced to provide an understanding of the physics governing the vibrations caused by a bearing with a raceway defect. This method is then used to detect a faulty bearing in two setups : on a lathe and in a dynamometer.
Show less  Date Issued
 2012
 PURL
 http://purl.flvc.org/FAU/3359156
 Subject Headings
 Marine turbines, Mathematical models, Vibration, Measurement, Fluid dynamics, Dynamic testing
 Format
 Document (PDF)
 Title
 The broken past: fractals in archaeology.
 Creator
 Liebovitch, Larry S., Brown, Clifford T., Witschey, Walter R. T.
 Date Issued
 20050301
 PURL
 http://purl.flvc.org/fau/165780
 Subject Headings
 Fractals, Nonlinear Systems, Chaos, ArchaeologyMathematical models
 Format
 Document (PDF)
 Title
 Modeling of linear induction machines for analysis and control.
 Creator
 Sinisterra, Armando Jose, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
 Abstract/Description

In this thesis, the analysis of the dynamic response of a Linear Induction Motor as an electromechanical system is done, accounting for all the governing equations implied in the process which are used to develop the corresponding simulation models. Once this model is presented, a feedback control system is implemented in order to analyze the controlled response of the motor, considering the applications and conditions analogue to aircraft launcher systems. Also a comparison between the...
Show moreIn this thesis, the analysis of the dynamic response of a Linear Induction Motor as an electromechanical system is done, accounting for all the governing equations implied in the process which are used to develop the corresponding simulation models. Once this model is presented, a feedback control system is implemented in order to analyze the controlled response of the motor, considering the applications and conditions analogue to aircraft launcher systems. Also a comparison between the Linear and Rotary induction motors describing the differences, similarities and equivalences will be developed.
Show less  Date Issued
 2011
 PURL
 http://purl.flvc.org/FAU/3172944
 Subject Headings
 Electric motors, Induction, Mathematical models, Electric propulsion, Control theory
 Format
 Document (PDF)