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- 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.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013963
- Subject Headings
- Organs-on-chips, Biomedical engineering
- Format
- Document (PDF)
- Title
- HYDRODYNAMIC PERFORMANCE AND SEAKEEPING ANALYSIS OF A CATAMARAN IN TRANSFORMING NEAR-SHORE HEAD AND FOLLOWING SEAS.
- Creator
- Ulgen, Kayhan, Dhanak, Manhar R., Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
A computational investigation of the hydrodynamic and seakeeping performance of a catamaran in calm, and in the presence of transforming head and following seas in waters of constant and varying depths is described. Parametric studies were conducted for a selected WAM-V 16 catamaran geometry using OpenFOAM® to uncover the physical phenomena. In the process a methodology has been developed for simulating the interactions between the vehicle and the shallow water environment akin to that in the...
Show moreA computational investigation of the hydrodynamic and seakeeping performance of a catamaran in calm, and in the presence of transforming head and following seas in waters of constant and varying depths is described. Parametric studies were conducted for a selected WAM-V 16 catamaran geometry using OpenFOAM® to uncover the physical phenomena. In the process a methodology has been developed for simulating the interactions between the vehicle and the shallow water environment akin to that in the coastal environment. The multiphase flow around the catamaran, including the six degrees-of-freedom motion of the vehicle, was modeled using a Volume of Fluid (VoF) method and solved using a dynamic mesh. The numerical approach was validated through computing benchmark cases and comparing the results with previous work. It is found that in a calm shallow water environment the total resistance, dynamic trim and sinkage of a catamaran in motion can be significantly impacted by the local water depth. The variations of the impact with depth and length-based Froude numbers are characterized. The impact varies as the vehicle moves from shallow waters to deep water or vice versa. In the presence of head and following small-amplitude seas, interesting interactions between incident waves and those generated by the vehicle are observed and are characterized for their variation with Froude number and water depth.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013942
- Subject Headings
- Seakeeping, Catamarans, Hydrodynamics, Computational fluid dynamics
- Format
- Document (PDF)
- Title
- Numerical Simulation of Marine Hydrokinetic Turbines in Realistic Operating Conditions.
- Creator
- Dunlap, Broc, VanZwieten, James, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
Marine Hydrokinetic (MHK) energy is an alternative to address the demand for cleaner energy sources. This study advanced numerical modeling tools and uses these to evaluate the performance of both a Tidal Turbine (TT) and an Ocean Current Turbine (OCT) operating in a variety of conditions. Inflow models are derived with current speeds ranging from 1.5 to 3 m/s and Turbulence Intensities (TI) of 5-15% and integrated into a TT simulation. An OCT simulation representing a commercial scale 20 m...
Show moreMarine Hydrokinetic (MHK) energy is an alternative to address the demand for cleaner energy sources. This study advanced numerical modeling tools and uses these to evaluate the performance of both a Tidal Turbine (TT) and an Ocean Current Turbine (OCT) operating in a variety of conditions. Inflow models are derived with current speeds ranging from 1.5 to 3 m/s and Turbulence Intensities (TI) of 5-15% and integrated into a TT simulation. An OCT simulation representing a commercial scale 20 m diameter turbine moored to the seafloor via underwater cable is enhanced with the capability to ingest Acoustic Doppler Current Profiler (ADCP) data and simulate fault conditions. ADCP measurements collected off the coast of Ft. Lauderdale during Hurricanes Irma and Maria were post-processed and used to characterize the OCT performance. In addition, a set of common faults were integrated into the OCT model to assess the system response in fault-induced scenarios.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013962
- Subject Headings
- Turbines, Ocean wave power, Simulations, Mathematical models
- Format
- Document (PDF)
- Title
- Numerical Simulation and Performance Characterization of Two Wave Energy Converters.
- Creator
- DePietro, Abigail R., VanZwieten, James, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
This research consists of the numerical model development and simulation of two prototype Wave Energy Convertor designs (WECs) across three simulation types. The first design is an oscillating body WEC called the Platypus designed to capture wave energy as three paddle arms actuate over the surface of the waves. The second design is an overtopping type WEC called the ROOWaC which captures and drains entrained water to generate power. Modeling of these systems was conducted using two...
Show moreThis research consists of the numerical model development and simulation of two prototype Wave Energy Convertor designs (WECs) across three simulation types. The first design is an oscillating body WEC called the Platypus designed to capture wave energy as three paddle arms actuate over the surface of the waves. The second design is an overtopping type WEC called the ROOWaC which captures and drains entrained water to generate power. Modeling of these systems was conducted using two techniques: the Morison load approach implemented using hydrodynamic response coefficients used to model the Platypus and a boundary element method (BEM) frequency-domain approach to model both WEC designs in the time domain. The BEM models included the development of hydrodynamic response coefficients using a discretized panel mesh of the system for calculation of added mass, excitation, and radiation forces. These three model families provided both performance predictions and power output information to WEC developers that supply important data for future full-scale designs. These models were used to predict power generation estimates for both WECs as follows: the Platypus WEC was predicted to have a maximum efficiency range between 14.5-35% and the ROOWaC WEC was predicted to generate a maximum peak average power of 19 W upon preliminary results.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013956
- Subject Headings
- Ocean energy resources--Research, Ocean wave power, Simulations, Mathematical methods and modelling
- Format
- Document (PDF)
- Title
- AN AUTOMATED ANCHORING SYSTEM FOR AN UNMANNED SURFACE VEHICLE.
- Creator
- Fosbrook, Amanda, Dhanak, Manhar, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
The goal of this thesis is to simulate, design and build an automated device that allows unmanned vessels to anchor themselves in specified locations while being United States Coast Guard Navigation Rules compliant. This is a part of a larger project funded by the U.S. Department of Energy for Florida Atlantic University to build an unmanned platform with an Undershot Water Wheel on it. By simulating the environment of the South Florida Intercoastal Water Ways, forces acting on the line,...
Show moreThe goal of this thesis is to simulate, design and build an automated device that allows unmanned vessels to anchor themselves in specified locations while being United States Coast Guard Navigation Rules compliant. This is a part of a larger project funded by the U.S. Department of Energy for Florida Atlantic University to build an unmanned platform with an Undershot Water Wheel on it. By simulating the environment of the South Florida Intercoastal Water Ways, forces acting on the line, anchor and the vessel are analyzed. These forces are used as the guide for the design and build of a line locking mechanism that takes the tension off the winch and a sensor package to monitor the environment the platform is in as well as control of the system. Based off experimental testing, the system was successful in handling all emulated environments with loads exceeding 150lbs of tension.
Show less - Date Issued
- 2021
- PURL
- http://purl.flvc.org/fau/fd/FA00013810
- Subject Headings
- Autonomous vehicles, Anchors
- Format
- Document (PDF)
- Title
- A Design Concept for Launch and Recovery of REMUS 100 AUV from WAM-V 16 USV.
- Creator
- Palmaccio, Brendan, Dhanak, Manhar, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
In this thesis, feasibility of a concept for launch and recovery of the Remus AUV from WAM-V USV is investigated. A modular recovery system which can be added to the WAM-V payload tray was designed, and based on a review of previous literature a CONOPS was developed for the launch and recovery process. The first phase of the CONOPS, which pertains to the position of the REMUS initially on the free surface prior to sling engagement is simulated using ANSYS AQWA. Preprocessing for the...
Show moreIn this thesis, feasibility of a concept for launch and recovery of the Remus AUV from WAM-V USV is investigated. A modular recovery system which can be added to the WAM-V payload tray was designed, and based on a review of previous literature a CONOPS was developed for the launch and recovery process. The first phase of the CONOPS, which pertains to the position of the REMUS initially on the free surface prior to sling engagement is simulated using ANSYS AQWA. Preprocessing for the simulation involved simplification of the model in ANSYS SpaceClaim to achieve a proper mesh as well as theoretical calculations of the input parameters for wave environment and point masses etc. The simulation was evaluated by taking into consideration two wave environment scenarios: beam sea’s (-90 degrees) and head seas (0 degrees). The wave environment was based on a linear frequency range for the waves which considered wavelengths that correspond to half and double the length of the WAM-V 16’. The significance of the simulation is characterized through identifying the ideal direction and wave frequency range for recovery based on the RAOs of the two vehicles.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014216
- Subject Headings
- Autonomous underwater vehicles--Design and construction, Marine engineering, Littoral combat ships
- Format
- Document (PDF)
- Title
- DEVELOPMENT OF MULTIFUNCTIONAL BETA-TRICALCIUM PHOSPHATE SCAFFOLDS FOR ANGIOGENESIS AND OSTEOGENESIS.
- Creator
- Qian, Enze, Kang, Yunqing, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
Rapid and efficient vascularization is still a considerable challenge of a tissue engineered β-tricalcium phosphate (β-TCP) scaffold. To overcome this challenge, branched channels were created in the porous scaffold to stimulate the instant flow of blood supply. The branched channeled porous β-TCP scaffold was fabricated using 3D printing and template-casting method. Human bone mesenchymal stem cells (hBMSC) and human umbilical vein endothelial cells (HUVEC) were seeded in the scaffolds and...
Show moreRapid and efficient vascularization is still a considerable challenge of a tissue engineered β-tricalcium phosphate (β-TCP) scaffold. To overcome this challenge, branched channels were created in the porous scaffold to stimulate the instant flow of blood supply. The branched channeled porous β-TCP scaffold was fabricated using 3D printing and template-casting method. Human bone mesenchymal stem cells (hBMSC) and human umbilical vein endothelial cells (HUVEC) were seeded in the scaffolds and characterized through double-stranded DNA (dsDNA) assay, alkaline phosphatase (ALP) assay and cell migration. Scaffolds were then implanted in the subcutaneous pockets in mice. Hematoxylin and eosin staining and Immunohistochemical staining on vascularization, bone-related markers were carried out. Results showed that branched channels significantly promoted HUVECs’ infiltration, migration, proliferation, and angiogenesis and also promote the proliferation and osteogenesis differentiation of hBMSCs. Scaffolds did not show significant pro-inflammatory effects. In vivo results showed that in the early stage after implantation, cells significantly migrated into branched channeled scaffolds compared to non-channeled and straight channeled scaffolds. More and matured blood vessels formed in the branched channeled scaffolds compared to in non-channeled and straight channeled scaffolds. Besides promoting vascularization, the branched channels also stimulated the infiltration of bone-related cells into the scaffolds. These results suggested that the geometric design of branched channels in the porous β-TCP scaffold promoted rapid vascularization and potentially stimulated bone cell recruitment. To further enhance the function of the scaffold to promote the MSCs differentiation, MnO2 hollow and solid nanoparticles were doped into the scaffold with different concentrations.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014193
- Subject Headings
- Tissue engineering, Bone Regeneration, Beta-tricalcium phosphate
- Format
- Document (PDF)
- Title
- A NEW DECELLULARIZED MATRIX FOR ENGINEERING AN ESOPHAGEAL CANCER MODEL IN A PERFUSION BIOREACTOR.
- Creator
- Brennan, Jordan Michael, Kang, Yunqing, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
The lack of physiologically relevant human esophageal cancer models has as a result that many esophageal cancer studies are encountering major bottleneck challenges in achieving breakthrough progress. To address the issue, here a 3D esophageal tumor tissue model was engineered using a biomimetic decellularized esophageal matrix in a customized bioreactor. To obtain a biomimetic esophageal matrix, a detergent-free, rapid decellularization method was developed to decellularize porcine esophagus...
Show moreThe lack of physiologically relevant human esophageal cancer models has as a result that many esophageal cancer studies are encountering major bottleneck challenges in achieving breakthrough progress. To address the issue, here a 3D esophageal tumor tissue model was engineered using a biomimetic decellularized esophageal matrix in a customized bioreactor. To obtain a biomimetic esophageal matrix, a detergent-free, rapid decellularization method was developed to decellularize porcine esophagus. The decellularized esophageal matrix (DEM) was characterized and the DEM was utilized for the growth of esophageal cancer cell KYSE30 in well plates and the bioreactor. Then the expression of cancerrelated markers of KYSE30 cells was analyzed and compared with formalin-fixed, paraffin-embedded (FFPE) esophageal squamous cell carcinoma (ESCC) tissue biospecimens. Results show that the detergent-free decellularization method preserved the esophageal matrix components and effectively removed cell nucleus. KYSE30 cancer cells proliferated well on and inside the DEM. KYSE30 cells cultured on the DEM in the dynamic bioreactor show different cancer marker expressions than those in the static well plate, and also share some similarities to the FFPE-ESCC biospecimens.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014206
- Subject Headings
- Cancer, Esophageal Neoplasms, Biomimetics
- Format
- Document (PDF)
- Title
- Optimized Parameters Fitting of a Poro-Elastic Acoustic Model with Ultrasonic Measurements for the Monitoring of Corroding Rebar in Reinforced Concrete.
- Creator
- Shaffer, Samuel, Beaujean, Pierre-Philippe, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
Traditional techniques of observing cracking within reinforced structures can be invasive, leading to an increased risk of added corrosion to structures already undergoing corrosive processes. The research presented in this document improves upon a nondestructive method for detecting early crack formation in reinforced concrete. This method includes using acoustic signaling to add a layer of salt water between the sensor and analyzed sample. Following the collection of surface and rebar echo...
Show moreTraditional techniques of observing cracking within reinforced structures can be invasive, leading to an increased risk of added corrosion to structures already undergoing corrosive processes. The research presented in this document improves upon a nondestructive method for detecting early crack formation in reinforced concrete. This method includes using acoustic signaling to add a layer of salt water between the sensor and analyzed sample. Following the collection of surface and rebar echo responses, an adapted version of the novel Biot-Stoll method is used to model sound propagation for poro-elastic mediums. Testing of model parameters and variables has improved the root mean square error (RMSE) by up to 63.7% when studying the full signal, and up to 62.6% for the rebar echo locations. These improvements signify better curve fitting between simulated and measured responses, which lead to increased accuracy in the model parameter outputs.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014265
- Subject Headings
- Reinforced concrete, Reinforcing bars--Corrosion, Ultrasonic testing
- Format
- Document (PDF)
- Title
- UNDERSTANDING BUBBLE GROWTH BEHAVIOR DURING NUCLEATE BOILING.
- Creator
- Ghazvini, Mahyar, Kim, Myeongsub, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
Boiling heat transfer associated with bubble growth is perhaps one of the most efficient cooling methodologies due to its sizeable latent heat during phase change. Despite significant advancement, numerous questions remain regarding the fundamentals of bubble growth mechanisms, a primary source of enhanced heat dissipation. This thesis provides a comprehensive examination of the mechanisms involved in the growth of bubbles during nucleate boiling. By conducting a combination of experiments...
Show moreBoiling heat transfer associated with bubble growth is perhaps one of the most efficient cooling methodologies due to its sizeable latent heat during phase change. Despite significant advancement, numerous questions remain regarding the fundamentals of bubble growth mechanisms, a primary source of enhanced heat dissipation. This thesis provides a comprehensive examination of the mechanisms involved in the growth of bubbles during nucleate boiling. By conducting a combination of experiments and numerical analyses, the goal is to enhance our understanding of bubble growth phenomena and their impact on heat transfer. Initially, the experimental work focuses on comparing the heat transfer performance and parameters related to bubble dynamics between regular and modified fin structures. The findings demonstrate that the modified fin structure, which featured artificial nucleation sites, exhibits superior heat transfer characteristics. This improvement is attributed to changes in the bubble departure diameter, bubble departure frequency, and growth time. Subsequently, an artificial neural network is developed to accurately predict the bubble departure diameter based on the wall superheat and subcooling level. This predictive model provides valuable insights into bubble behavior originating from artificial nucleation sites.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014295
- Subject Headings
- Nucleate boiling, Ebullition, Heat--Transmission
- Format
- Document (PDF)
- Title
- Some topics related to the vibrations of deterministic and non-deterministic metamaterial structures.
- Creator
- Li, Yuchen, Elishakoff, Isaac, Challamel, Noël, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
In this thesis, we will explore different kinds of metamaterial or architectural structural problems, including structures composed of heterogeneous media with bi periodic sub-structures, discrete structures with sub-elements or continuous structures with discrete attached sub-elements. The thesis is composed of seven parts. After having introduced the specificities of metamaterial mechanics, the second chapter is devoted to the vibration of discrete beam problems called Hencky bar-chain...
Show moreIn this thesis, we will explore different kinds of metamaterial or architectural structural problems, including structures composed of heterogeneous media with bi periodic sub-structures, discrete structures with sub-elements or continuous structures with discrete attached sub-elements. The thesis is composed of seven parts. After having introduced the specificities of metamaterial mechanics, the second chapter is devoted to the vibration of discrete beam problems called Hencky bar-chain model in a stochastic framework. It is shown that the lattice beam behaves as a nonlocal continuous beam problem, both in the deterministic and the non-deterministic analyses. The third chapter considers the vibration of continuous beams with the introduction of shear effects and attached periodically oscillators. A discussion on beam modelling, for example Timoshenko beam models or truncated Timoshenko beam models is included. It is shown that the bandgap phenomenon observed for metamaterial beams can be accurately captured by a truncated Timoshenko beam model which means the last term in the Timoshenko equation is not that important.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014289
- Subject Headings
- Metamaterials, Hencky bar-chain model, Lattice theory, Engineering
- Format
- Document (PDF)
- Title
- INVESTIGATING THE ROLE OF BIOMOLECULE/MINERAL INTERACTIONS VIA CALCITE AND CELESTITE MODEL SYSTEMS.
- Creator
- Martin, Andrienne, Merk, Vivian, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
In this research, we use calcite and celestite inorganic model systems to better understand biological crystallization in the presence of organic biomolecules. Our goal is to understand what happens when biomolecules occlude into crystals and how that affects the structural organization. Specifically, we focus on the role the respective biomolecule chemistry plays in regulating the incorporation into a crystal. To visualize and characterize the biomolecule/mineral role in crystallization, a...
Show moreIn this research, we use calcite and celestite inorganic model systems to better understand biological crystallization in the presence of organic biomolecules. Our goal is to understand what happens when biomolecules occlude into crystals and how that affects the structural organization. Specifically, we focus on the role the respective biomolecule chemistry plays in regulating the incorporation into a crystal. To visualize and characterize the biomolecule/mineral role in crystallization, a variety of techniques were used to image and analyze the respective model systems. The synthesized single crystals were characterized by light microscopy (LM). Scanning electron microscopy (SEM) and field-emission SEM (FE-SEM) were used to examine the morphology of the crystals. Structural and topographical analyses were carried out using atomic force microscopy (AFM). Fourier transform infrared spectroscopy (FTIR) and confocal Raman microscopy were both used to characterize functional groups, where Raman spectroscopic mappings provided the region-specific chemical composition of the crystal.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014287
- Subject Headings
- Crystallization, Biomolecules, Calcite, Celestite
- Format
- Document (PDF)
- Title
- MICROFLUIDIC ELECTRICAL IMPEDANCE TECHNOLOGY FOR POINT-OFCARE ASSESSMENT OF SICKLE CELL DISEASE.
- Creator
- Dieujuste, Darryl, Du, Sarah, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
Sickle Cell Disease (SCD) is a genetic disease that affects approximately 100,000 people in the USA and millions worldwide. The disease is defined by a mutation in hemoglobin, the red blood cell’s oxygen carrying component. Under hypoxic (low oxygen) conditions, the mutated hemoglobin (known as HbS) polymerizes into rigid fibers that stretch the cell into a sickle shape. These rigid cells can occlude blood vessels and cause an individual immense pain. Currently, no point-of-care devices exist...
Show moreSickle Cell Disease (SCD) is a genetic disease that affects approximately 100,000 people in the USA and millions worldwide. The disease is defined by a mutation in hemoglobin, the red blood cell’s oxygen carrying component. Under hypoxic (low oxygen) conditions, the mutated hemoglobin (known as HbS) polymerizes into rigid fibers that stretch the cell into a sickle shape. These rigid cells can occlude blood vessels and cause an individual immense pain. Currently, no point-of-care devices exist in the market for assisting those with SCD. Using microfluidics with custom designed portable impedance measuring hardware we can achieve label-free in vitro analyses of SCD rheology. This dissertation presents two impedance-based devices for finger-prick volume blood testing, including a microflow cytometer for SCD diagnostics and a vaso-occlusion tester for monitoring blood flow activities. First, the microflow cytometer is validated by measuring the electrical impedance of individual cells flowing through a narrow microfluidic channel. Cellular impedance is interpreted by changes in subcellular components due to oxygen association-dissociation of hemoglobin, using an equivalent circuit model and Multiphysics simulation. Impedance values of sickle cells exhibit remarkable deviations from normal blood cells. Such deviation is quantified by a conformity score, which allows for measurement of SCD heterogeneity, and potentially disease severity. Findings from this study demonstrate the potential for SCD screening via electrical impedance. Second, a vaso-occlusion tester is validated by measuring the impedance response of blood flow within a microfluidic mimic of capillary bed.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014243
- Subject Headings
- Sickle cell anemia, Microfluidics, Point-of-care testing, Electric Impedance
- Format
- Document (PDF)
- Title
- DESIGN AND FAILURE ANALYSIS OF MULTI-COMPONENT MOORING LINES WITH NON-LINEAR POLYMER SPRINGS FOR FLOATING OFFSHORE WIND TURBINES.
- Creator
- McFadden, Jared, Mahfuz, Hassan, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
This research studied the effects of mooring line pretension, spring safe working load, and spring response curve on peak loads and platform surge. The maximum tension load from the optimized assembly was applied to a modelled section of 8-strand multiplait rope to study stress concentrations. The analyses yielded a mooring line pretensioned at 1250 kN with a 4500 kN safe working load degressive spring was optimal. Fatigue damage from 12-hour duration of 50-year storm conditions was 8.04 × 10...
Show moreThis research studied the effects of mooring line pretension, spring safe working load, and spring response curve on peak loads and platform surge. The maximum tension load from the optimized assembly was applied to a modelled section of 8-strand multiplait rope to study stress concentrations. The analyses yielded a mooring line pretensioned at 1250 kN with a 4500 kN safe working load degressive spring was optimal. Fatigue damage from 12-hour duration of 50-year storm conditions was 8.04 × 10−6. Infinite life is predicted at annual average conditions. The peak tension from 50-year storm conditions of 3671 kN and annual average conditions of 1388 kN was applied to the section model, yielding a maximum stress of 3.70 × 108 Pa and 2.01 × 108 Pa, respectively, from friction and longitudinal compression of the rope’s cross section. The maximum stress from the static structural analysis was 33.5% of polyester’s ultimate strength, based on the maximum stress failure criterion.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014245
- Subject Headings
- Wind turbines--Design and construction, Wind turbines--Testing, Deep-sea moorings
- Format
- Document (PDF)
- Title
- CORROSION MONITORING AND ANALYSIS OF REINFORCED CONCRETE: CORROSION RESISTANT ALLOYS AFTER LONG TERM EXPOSURE TO CHLORIDES.
- Creator
- Taylor, Redmayne, Presuel-Moreno, Francisco, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
- Abstract/Description
-
Reinforced concrete (RC) is the building block of modern architecture and industry. The failure of which is costly and dangerous. Typically made with carbon steel rebars, corrosion resistant alloys provide an alternative method of delaying failure. Stainless steels, while more expensive than carbon steels, provide excellent corrosion resistance, but less is known about the long term monitoring of corrosion activity for stainless steel than for carbon steel. This study looks at samples...
Show moreReinforced concrete (RC) is the building block of modern architecture and industry. The failure of which is costly and dangerous. Typically made with carbon steel rebars, corrosion resistant alloys provide an alternative method of delaying failure. Stainless steels, while more expensive than carbon steels, provide excellent corrosion resistance, but less is known about the long term monitoring of corrosion activity for stainless steel than for carbon steel. This study looks at samples prepared between 2005 and 2009 using 304SS, 316SS, and 2304SS rebars, as well as SMI and Stelax stainless steel clad carbon steel reinforcements embedded in three different concrete mixes. These selected samples are split into two exposure environments, inside humidity chambers within the laboratory and outdoor exposure. Measurements reported here were made monthly over the course of 250 plus days using the Galvanostatic Pulse method, Electrochemical Impedance Spectroscopy, and a Gecor 8 device. These methods were used to determine corrosion current, isolated corrosion current density, and solution resistance. Corrosion current density values calculated from measurements by the Galvanostatic Pulse and Electrochemical Impedance Spectroscopy method are too small to indicate corrosion, based on value ranges provided by Andrade. However, Gecor 8 corrosion current density values indicate low levels or moderate levels of corrosion for all samples compared to the Andrade’s value ranges. The area used by the Gecor is unknown, so it’s possible this is driving up the measured values.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014258
- Subject Headings
- Reinforced concrete, Corrosion resistant alloys, Carbon steel, Corrosion
- Format
- Document (PDF)
- Title
- Automated Launch and Recovery of an Autonomous Underwater Vehicle from an Unmanned Surface Vessel.
- Creator
- Sarda, Edoardo I, Dhanak, Manhar R., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
Research on collaboration among unmanned platforms is essential to improve the applications for autonomous missions, by expanding the working environment of the robotic systems, and reducing the risks and the costs associated with conducting manned operations. This research is devoted to enable the collaboration between an Unmanned Surface Vehicle (USV) and an Autonomous Underwater Vehicle (AUV), by allowing the first one to launch and recover the second one. The objective of this...
Show moreResearch on collaboration among unmanned platforms is essential to improve the applications for autonomous missions, by expanding the working environment of the robotic systems, and reducing the risks and the costs associated with conducting manned operations. This research is devoted to enable the collaboration between an Unmanned Surface Vehicle (USV) and an Autonomous Underwater Vehicle (AUV), by allowing the first one to launch and recover the second one. The objective of this dissertation is to identify possible methods to launch and recover a REMUS 100 AUV from a WAM-V 16 USV, thus developing this capability by designing and implementing a launch and recovery system (LARS). To meet this objective, a series of preliminary experiments was first performed to identify two distinct methods to launch and recover the AUV: mobile and semi-stationary. Both methods have been simulated using the Orcaflex software. Subsequently, the necessary control systems to create the mandatory USV autonomy for the purpose of launch and recovery were developed. Specifically, a series of low-level controllers were designed and implemented to enable two autonomous maneuvers on the USV: station-keeping and speed & heading control. In addition, a level of intelligence to autonomously identify the optimal operating conditions within the vehicles' working environment, was derived and integrated on the USV. Lastly, a LARS was designed and implemented on the vehicles to perform the operation following the proposed methodology. The LARS and all subsystems developed for this research were extensively tested through sea-trials. The methodology for launch and recovery, the design of the LARS and the experimental findings are reported in this document.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004631, http://purl.flvc.org/fau/fd/FA00004631
- Subject Headings
- Underwater acoustic telemetry., Fuzzy systems., Nonlinear control theory., Adaptive signal processing., Oceanographic submersibles--Automatic control., Submersibles--Control systems.
- 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.
Show less - 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
- 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.
Show less - 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
- A Hybrid System for Simulation of Athletic Activities Related to Lower Extremity Biomechanics.
- Creator
- Trepeck, Cameron, Hashemi, Javad, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
In this dissertation, the design and development of a hybrid robotic system that simulates dynamic biomechanical tasks of the lower extremity with emphasis on knee and hip joints are presented. The hybrid system utilizes a mechanical hip and a cadaveric knee/ankle component and can accelerate the whole complex towards the ground. This system is used to simulate complex athletic movements such as landing from a jump at various anatomical orientations of the lower extremity with muscle action....
Show moreIn this dissertation, the design and development of a hybrid robotic system that simulates dynamic biomechanical tasks of the lower extremity with emphasis on knee and hip joints are presented. The hybrid system utilizes a mechanical hip and a cadaveric knee/ankle component and can accelerate the whole complex towards the ground. This system is used to simulate complex athletic movements such as landing from a jump at various anatomical orientations of the lower extremity with muscle action. The dynamic response of the lower extremity is monitored and analyzed during impulsive contact between the ground and the cadaveric leg. The cadaveric knee is instrumented to measure strain of the Anterior Cruciate Ligament (ACL) during simulated high impact sports activities. The mechanical hip allows various kinematics of the hip including flexion as well as abduction. In addition to the flexion and abduction of the mechanical hip, the controlled flexion and extension of the cadaveric knee allows for simulation of complex tasks such as landing from a jump. A large number of tests were performed at various anatomical positions utilizing this device to simulate landing from a jump. ACL strain was measured during these tasks using a Differential Variance Resistance Transducer (DVRT). Ground Reaction Force and muscle forces were measured and monitored using AmCell load cells recorded using the LabView software. one-inch and 6-inch jump landing heights were used for all the simulations. The tests were performed at differing angles of hip flexion (0°, 30°, 45°, 60°) and at two different ankle positions. Plantar flexion and flat-footed landing conditions were simulated and compared in all degrees of hip flexion. These tests were repeated with and without hip abduction in order to study the effects of these landing positions on ACL strain. Hip flexion was found to effect ACL strain: as angle of hip flexion increases, ACL strain decreases. This occurred in both abducted and non-abducted hip positions. Ankle landing position had an effect only in small drop heights, while hip abduction had an effect in large drops. Future tests must be completed to further study these effects. These studies showed that the robotic system can simulate dynamic tasks, apply muscle forces, and move the cadaveric tissue in three dimensional biomechanical positions.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004898, http://purl.flvc.org/fau/fd/FA00004898
- Subject Headings
- Musculoskeletal system--Wounds and injuries., Musculoskeletal system--Mechanical properties., Biomechanics--Computer simulation., Human mechanics., Artificial joints.
- Format
- Document (PDF)
- Title
- A direct thrust measurement system for a waterjet propelled, free running USV.
- Creator
- Grimes, John A., von Ellenrieder, Karl, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
The relationship between cross-flow at a waterjet inlet and delivered thrust is not fully understood. A direct thrust measurement system was designed for a waterjet propelled, free running USV. To induce sway velocity at the waterjet inlet, which was considered equivalent to the cross flow, circles of varying radii were performed at Reynolds Numbers between 3.48 x 106 and 8.7 x 106 and radii from 2.7 to 6.3 boat lengths. Sway velocities were less than twenty percent of mean forward speed with...
Show moreThe relationship between cross-flow at a waterjet inlet and delivered thrust is not fully understood. A direct thrust measurement system was designed for a waterjet propelled, free running USV. To induce sway velocity at the waterjet inlet, which was considered equivalent to the cross flow, circles of varying radii were performed at Reynolds Numbers between 3.48 x 106 and 8.7 x 106 and radii from 2.7 to 6.3 boat lengths. Sway velocities were less than twenty percent of mean forward speed with slip angles that were less than 20°. Thrust Loading Coefficients were compared to sway as a percent of forward speed. In small radius turns, no relationship was seen, while in larger radius turns, peaks of sway velocity corresponded with drops in thrust, but this was determined to be caused by reduced vehicle yaw in these intervals . Decoupling of thrust and yaw rate is recommended for future research.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004023
- Subject Headings
- Oceanographic instruments -- Evaluation, Propellers, Ship propulsion, Ships -- Hydrodynamics, Stability of ships
- Format
- Document (PDF)