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(1 - 9 of 9)
- Title
- THE RESPONSE OF A GENERAL CIRCULATION CLIMATE MODEL TOHIGH LATITUDE FRESHWATER FORCING IN THE ATLANTIC BASINWITH RESPECT TOTROPICAL CYCLONE-LIKE VORTICES.
- Creator
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Paulis, Victor, Clarke, Thomas, University of Central Florida
- Abstract / Description
-
The current cycle of climate change along with increases in hurricane activity, changing precipitation patterns, glacial melt, and other extremes of weather has led to interest and research into the global correlation or teleconnection between these events. Examination of historical climate records, proxies and observations is leading to formulation of hypotheses of climate dynamics with modeling and simulation being used to test these hypotheses as well as making projections. Ocean currents...
Show moreThe current cycle of climate change along with increases in hurricane activity, changing precipitation patterns, glacial melt, and other extremes of weather has led to interest and research into the global correlation or teleconnection between these events. Examination of historical climate records, proxies and observations is leading to formulation of hypotheses of climate dynamics with modeling and simulation being used to test these hypotheses as well as making projections. Ocean currents are believed to be an important factor in climate change with thermohaline circulation (THC) fluctuations being implicated in past cycles of abrupt change. Freshwater water discharge into high-latitude oceans attributed to changing precipitation patterns and glacial melt, particularly the North Atlantic, has also been associated with historical abrupt climate changes and is believed to have inhibited or shut down the THC overturning mechanism by diluting saline surface waters transported from the tropics. Here we analyze outputs of general circulation model (GCM) simulations parameterized by different levels of freshwater flux (no flux (control), 0.1 Sverdrup (Sv) and 1.0 Sv) with respect to tropical cyclone-like vortices (TCLVs) to determine any trend in simulated tropical storm frequency, duration, and location relative to flux level, as well as considering the applicability of using GCMs for tropical weather research. Increasing flux levels produced fewer storms and storm days, increased storm duration, a southerly and westerly shift (more pronounced for the 0.1 Sv level) in geographic distribution and increased activity near the African coast (more pronounced for the 1.0 Sv level). Storm intensities and tracks were not realistic compared to observational (real-life) values and is attributed to the GCM resolution not being fine enough to realistically simulate storm (microscale) dynamics.
Show less - Date Issued
- 2007
- Identifier
- CFE0001810, ucf:47339
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001810
- Title
- WHAT'S BLACK AND WHITE AND NOT READ ALL OVER?: AN EXAMINATION OF THE EVOLVING LANDSCAPE OF NEWSPAPERS THROUGH THE LENS OF THE NEW YORK TIMES.
- Creator
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Reiber, Anne, Bagley, George, Brunson, Richard, University of Central Florida
- Abstract / Description
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The research and statistics gathered in this thesis begin in 2000. Newspapers began experiencing change due to technology before 2000. However, the information necessary to complete this thesis only goes back to that year. Since the year 2000, the newspaper industry has struggled to adapt to the age of ever-changing technology. Newspapers across the US, including large and well-established publications have been forced to find new strategies that allow them to keep up with new digital...
Show moreThe research and statistics gathered in this thesis begin in 2000. Newspapers began experiencing change due to technology before 2000. However, the information necessary to complete this thesis only goes back to that year. Since the year 2000, the newspaper industry has struggled to adapt to the age of ever-changing technology. Newspapers across the US, including large and well-established publications have been forced to find new strategies that allow them to keep up with new digital technologies. The New York Times was the focus of this study, but it is only one part of a very large industry. However, it is one of the most successful papers of the digital age and offers a thorough look into the newspaper industry. Therefore, its strategies to adapt to digital and its overall business model were compared to newspapers throughout the nation. The intent of this thesis is to have a better understanding of the future of the newspaper industry in the digital age, including newspapers in small, medium and large markets. A look into The New York Times' history provides a better understanding of how newspapers have already been affected by the digital age, and its business model offers guidance for other newspapers on how to adapt. This thesis focused on analyzing at least one newspaper to represent each market including a small, medium and large market newspaper then determining if the methods The New York Times uses would be adaptable and scalable to their newspapers. This thesis determines which newspapers could use The New York Times' strategies to their benefit and draws conclusions on the future of the newspaper industry as a whole.
Show less - Date Issued
- 2017
- Identifier
- CFH2000271, ucf:45847
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000271
- Title
- ANALYSIS, MODELING, AND SIMULATION OF THE TIDES IN THE LOXAHATCHEE RIVER ESTUARY (SOUTHEASTERN FLORIDA).
- Creator
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Bacopoulos, Peter, Hagen, Scott, University of Central Florida
- Abstract / Description
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Recent cooperative efforts between the University of Central Florida, the Florida Department of Environmental Protection, and the South Florida Water Management District explore the development of a two-dimensional, depth-integrated tidal model for the Loxahatchee River estuary (Southeastern Florida). Employing a large-domain approach (i.e., the Western North Atlantic Tidal model domain), two-dimensional tidal flows within the Loxahatchee River estuary are reproduced to provide: 1)...
Show moreRecent cooperative efforts between the University of Central Florida, the Florida Department of Environmental Protection, and the South Florida Water Management District explore the development of a two-dimensional, depth-integrated tidal model for the Loxahatchee River estuary (Southeastern Florida). Employing a large-domain approach (i.e., the Western North Atlantic Tidal model domain), two-dimensional tidal flows within the Loxahatchee River estuary are reproduced to provide: 1) recommendations for the domain extent of an integrated, surface/groundwater, three-dimensional model; 2) nearshore, harmonically decomposed, tidal elevation boundary conditions. Tidal simulations are performed using a two-dimensional, depth-integrated, finite element-based code for coastal and ocean circulation, ADCIRC-2DDI. Multiple variations of an unstructured, finite element mesh are applied to encompass the Loxahatchee River estuary and different spatial extents of the Atlantic Intracoastal Waterway (AIW). Phase and amplitude errors between model output and historical data are quantified at five locations within the Loxahatchee River estuary to emphasize the importance of including the AIW in the computational domain. In addition, velocity residuals are computed globally to reveal significantly different net circulation patterns within the Loxahatchee River estuary, as depending on the spatial coverage of the AIW.
Show less - Date Issued
- 2006
- Identifier
- CFE0000925, ucf:46755
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000925
- Title
- ESTUARINE INFLUENCE ON TIDALLY DRIVEN CIRCULATION IN THE SOUTH ATLANTIC BIGHT.
- Creator
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Bacopoulos, Peter, Hagen, Scott, University of Central Florida
- Abstract / Description
-
A high-resolution, finite element-based, shallow water equation model is developed to simulate the tides in the South Atlantic Bight. The model is constructed to include all of the estuarine features along the southeastern United States seaboard: coastal inlets, rivers and tidal creeks, sounds and lagoons, intertidal zones including salt marshes and mangrove swamps, and the Atlantic Intracoastal Waterway. The estuaries are represented in the finite element mesh using triangular elements with...
Show moreA high-resolution, finite element-based, shallow water equation model is developed to simulate the tides in the South Atlantic Bight. The model is constructed to include all of the estuarine features along the southeastern United States seaboard: coastal inlets, rivers and tidal creeks, sounds and lagoons, intertidal zones including salt marshes and mangrove swamps, and the Atlantic Intracoastal Waterway. The estuaries are represented in the finite element mesh using triangular elements with side lengths on the order of tens of meters. Also incorporated into the model is a spatially distributed bottom friction parameterization, based on the various landcover and benthic characteristics in the domain. The motivation to use this comprehensive representation of the system was inspired by a desire to capably account for the full estuarine tidal physics. In this approach, no calibration is performed and the model is used as a tool to assess the physical processes it describes. Upon its development, the model is first validated by accurately simulating tidal hydrodynamics in the South Atlantic Bight including the described estuaries. Variants of the model are then constructed by selectively removing estuarine features from the domain. All model representations are subsequently applied in nearly identical simulations: the only differing factor between the simulations being the inland extent of the estuaries described. The solutions are compared with respect to including versus excluding the estuarine features of the domain. Where water surface elevations are shown to be unaffected by the estuarine features of the South Atlantic Bight, tidal velocities exhibit far more sensitivity. This effect is pronounced locally, with regional effects extending offshore. Further analysis is performed on cross-sectional flows recomposed locally and on tidal energetics diagnosed throughout the domain. It is discovered that the high frictional environment of the vast estuarine surface area plays a role in local and regional tidal circulation in the South Atlantic Bight.
Show less - Date Issued
- 2009
- Identifier
- CFE0002891, ucf:48028
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002891
- Title
- X-ray Radiation Enabled Cancer Detection and Treatment with Nanoparticles.
- Creator
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Hossain, Mainul, Su, Ming, Behal, Aman, Gong, Xun, Hu, Haiyan, Kapoor, Vikram, Deng, Weiwei, University of Central Florida
- Abstract / Description
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Despite significant improvements in medical sciences over the last decade, cancer still continues to be a major cause of death in humans throughout the world. Parallel to the efforts of understanding the intricacies of cancer biology, researchers are continuously striving to develop effective cancer detection and treatment strategies. Use of nanotechnology in the modern era opens up a wide range of possibilities for diagnostics, therapies and preventive measures for cancer management....
Show moreDespite significant improvements in medical sciences over the last decade, cancer still continues to be a major cause of death in humans throughout the world. Parallel to the efforts of understanding the intricacies of cancer biology, researchers are continuously striving to develop effective cancer detection and treatment strategies. Use of nanotechnology in the modern era opens up a wide range of possibilities for diagnostics, therapies and preventive measures for cancer management. Although, existing strategies of cancer detection and treatment, using nanoparticles, have been proven successful in case of cancer imaging and targeted drug deliveries, they are often limited by poor sensitivity, lack of specificity, complex sample preparation efforts and inherent toxicities associated with the nanoparticles, especially in case of in-vivo applications. Moreover, the detection of cancer is not necessarily integrated with treatment. X-rays have long been used in radiation therapy to kill cancer cells and also for imaging tumors inside the body using nanoparticles as contrast agents. However, X-rays, in combination with nanoparticles, can also be used for cancer diagnosis by detecting cancer biomarkers and circulating tumor cells. Moreover, the use of nanoparticles can also enhance the efficacy of X-ray radiation therapy for cancer treatment.This dissertation describes a novel in vitro technique for cancer detection and treatment using X-ray radiation and nanoparticles. Surfaces of synthesized metallic nanoparticles have been modified with appropriate ligands to specifically target cancer cells and biomarkers in vitro. Characteristic X-ray fluorescence signals from the X-ray irradiated nanoparticles are then used for detecting the presence of cancer. The method enables simultaneous detection of multiple cancer biomarkers allowing accurate diagnosis and early detection of cancer. Circulating tumor cells, which are the primary indicators of cancer metastasis, have also been detected where the use of magnetic nanoparticles allows enrichment of rare cancer cells prior to detection. The approach is unique in that it integrates cancer detection and treatment under one platform, since, X-rays have been shown to effectively kill cancer cells through radiation induced DNA damage. Due to high penetrating power of X-rays, the method has potential applications for in vivo detection and treatment of deeply buried cancers in humans. The effect of nanoparticle toxicity on multiple cell types has been investigated using conventional cytotoxicity assays for both unmodified nanoparticles as well as nanoparticles modified with a variety of surface coatings. Appropriate surface modifications have significantly reduced inherent toxicity of nanoparticles, providing possibilities for future clinical applications. To investigate cellular damages caused by X-ray radiation, an on-chip biodosimeter has been fabricated based on three dimensional microtissues which allows direct monitoring of responses to X-ray exposure for multiple mammalian cell types. Damage to tumor cells caused by X-rays is known to be significantly higher in presence of nanoparticles which act as radiosensitizers and enhance localized radiation doses. An analytical approach is used to investigate the various parameters that affect the radiosensitizing properties of the nanoparticles. The results can be used to increase the efficacy of nanoparticle aided X-ray radiation therapy for cancer treatment by appropriate choice of X-ray beam energy, nanoparticle size, material composition and location of nanoparticle with respect to the tumor cell nucleus.
Show less - Date Issued
- 2012
- Identifier
- CFE0004547, ucf:49242
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004547
- Title
- Computational Fluid Dynamics Proof of Concept and Analysis of a Self-Powered Fontan Circulation.
- Creator
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Ni, Marcus, Kassab, Alain, Divo, Eduardo, Chopra, Manoj, University of Central Florida
- Abstract / Description
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The Fontan circulation is a result of the last (third stage) surgical procedure to correct a single ventricle congenital cardiac disorder in children. Although the Fontan circulation has been successfully established in surgeries over the years, it is flawed and can lead in certain cases to pre-mature death. The main cause of this failure is due to increased pulmonary vascular resistance due to loss pulse pressure and blood flow. In healthy circulations, the heart pumps directly to the lungs,...
Show moreThe Fontan circulation is a result of the last (third stage) surgical procedure to correct a single ventricle congenital cardiac disorder in children. Although the Fontan circulation has been successfully established in surgeries over the years, it is flawed and can lead in certain cases to pre-mature death. The main cause of this failure is due to increased pulmonary vascular resistance due to loss pulse pressure and blood flow. In healthy circulations, the heart pumps directly to the lungs, where as (")Single Ventricle(") patients must use a single sided heart to supply blood to the rest of the body before the lungs. Improvements to the Fontan circulation have been proposed, but they require extensive care or external devices. We propose a (")Self-Powered(") Fontan circulation that will inject energy into the pulmonary system by adding an injection jet shunt (IJS) directly from the heart. The IJS will provide the pulse pressure, blood flow, and entrainment that the pulmonary vascular system needs to function at a healthy level. The difference between a healthy and sick Fontan circulation is 3-5[mmHg] in the IVC. The goal of the IJS is to cause this 3-5[mmHg] pressure drop in the IVC. In the analysis of the Fontan, ascertaining energy losses due to flow jet impingements and flow mixing is critical. Moreover, in order to better understand surgical alternatives is it important to have a robust multi-scale 0D-3D CFD analysis tool that permits investigation of surgical alternatives in a virtual physics-based environment. To this end, a lumped parameter model (LPM) is tightly coupled at the time step level with a full 3D computational fluid dynamics (CFD) model. Using this model scheme, the Fontan test section is no longer being modeled by the LPM. Therefore, it is not limited by the 0D nature of the vascular resistance, capacitance, and inertia bed model. The CFD can take over at the area of interest which accounts for flow directionality and momentum transfer that the LPM is unable to capture. To efficiently calculate optimal IJS configurations, a closed loop steady state model was created to solve a simplified Fontan circulation in 3D. Three models were created with several different optimized configurations, a synthetic model (average dimensions of 2-4 year-old Fontan patients), and two patient-specific models (10 and 24-year-old). The model configurations include changes in the IJS nozzle diameter and IJS placement along the pulmonary artery. These configurations are compared to a baseline model with no IJS. All three models suggest that the IJS helps to decrease IVC pressure while increasing pulse pressure and blood flow to the pulmonary system.
Show less - Date Issued
- 2017
- Identifier
- CFE0006630, ucf:51303
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006630
- Title
- MASS CONSERVATION ANALYSIS FOR THE LOWER ST. JOHNS RIVER USING CONTINUOUS AND DISCONTINUOUS GALERKIN FINITE ELEMENT METHODS.
- Creator
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Thomas, Lillie, Hagen, Scott, University of Central Florida
- Abstract / Description
-
This thesis provides a mass conservation analysis of the Lower St. Johns River for the purpose of providing basis for future salinity transport modeling. The analysis provides an assessment of the continuous (CG) and discontinuous (DG) Galerkin finite element methods with respect to their mass conservation properties. The following thesis also presents a rigorous literature review pertaining to salinity transport in the Lower St. Johns River, from which this effort generates the data used to...
Show moreThis thesis provides a mass conservation analysis of the Lower St. Johns River for the purpose of providing basis for future salinity transport modeling. The analysis provides an assessment of the continuous (CG) and discontinuous (DG) Galerkin finite element methods with respect to their mass conservation properties. The following thesis also presents a rigorous literature review pertaining to salinity transport in the Lower St. Johns River, from which this effort generates the data used to initialize and validate numerical simulations. Two research questions are posed and studied in this thesis: can a DG-based modeling approach produce mass conservative numerical solutions; and what are the flow interactions between the river and the marshes within the coastal region of the Lower St. Johns River? Reviewing the available data provides an initial perspective of the ecosystem. For this, salinity data are obtained and assembled for three modeling scenarios. Each scenario, High Extreme, Most Variable, and Low Extreme, is 30 days long (taken from year 1999) and represents a unique salinity regime in the Lower St. Johns River. Time-series of salinity data is collected at four stations in the lower and middle reaches of the Lower St. Johns River, which provides a vantage point for assessing longitudinal variation of salinity. As an aside, precipitation and evaporation data is presented for seven stations along the entire St. Johns River, which provides added insight into salinity transport in the river. A mass conservation analysis is conducted for the Lower St. Johns River. The analysis utilizes a segmentation of the Lower St. Johns River, which divides the domain into sections based on physical characteristics. Mass errors are then calculated for the CG and DG finite element methods to determine mass conservative abilities. Also, the flow interactions (i.e., volume exchange) between the river and marshes are evaluated through the use of tidal prisms. The CG- and DG- finite element methods are then tested in tidal simulation performance, which the results are then compared to observed tides and tidal currents at four stations within the lower portion of the Lower St. Johns River. Since the results show that the DG model outperforms the CG model, the DG model is used in the tidally driven salinity transport simulations. Using four stations within the lower and middle part of the Lower St. Johns River, simulated and observed water levels and salinity concentrations are compared.
Show less - Date Issued
- 2011
- Identifier
- CFE0003736, ucf:48797
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003736
- Title
- Ok, Ladies, Now Let's Get Information: Recognizing Moments of Rhetorical Identification in Beyonc(&)#233;'s Digital Activism.
- Creator
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Arban, Garrett, Jones, Natasha, Vie, Stephanie, Wheeler, Stephanie, University of Central Florida
- Abstract / Description
-
This research seeks to understand how activists are encouraging audiences to identify with their work in digital spaces through a case study of Beyonc(&)#233; Knowles-Carter's activism. The current scholarship surrounding digital activism is extensive and has offered a detailed look at individual tools used in activist movements, but there is a lack of research that recognizes the complex network of tools that are often used by an activist or activist group. To address this gap in the...
Show moreThis research seeks to understand how activists are encouraging audiences to identify with their work in digital spaces through a case study of Beyonc(&)#233; Knowles-Carter's activism. The current scholarship surrounding digital activism is extensive and has offered a detailed look at individual tools used in activist movements, but there is a lack of research that recognizes the complex network of tools that are often used by an activist or activist group. To address this gap in the research, this thesis offers an analysis of three specific activist tools used by Beyonc(&)#233; to encourage her fans and other audiences to identify with and participate in her activism. This study investigates the methods Beyonc(&)#233; employs to get her multiple audiences informed and engaged through an analysis of her activist blog, the (")Formation(") music video, and her live performance during the 2016 Super Bowl halftime show. Specifically, the purpose of this study is to assess, from a rhetorical standpoint, how Beyonc(&)#233; is inviting her audiences to respond and become engaged.The analysis of these three activist tools utilizes qualitative data analysis, focusing on Burke's (1969) concept of rhetorical identification to understand how her activist messages are presented across mediums. To expand on the findings of this analysis, a reception study on Beyonc(&)#233;'s (")Formation(") music video and 2016 Super Bowl performance was conducted to gauge the success of her rhetorical methods. The findings of this study recognize the need to continue looking at the multiple tools used by activists to understand the complexity of their rhetorical work online. This study also provides methods for analyzing the intertextual nature of digital activism so that further research can be done. While this study begins to address the gap in the current scholarship, more research needs to be done to study the current rhetorical practices of digital activists.
Show less - Date Issued
- 2017
- Identifier
- CFE0006557, ucf:51344
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006557
- Title
- A COUPLED CFD-LUMPED PARAMETER MODEL OF THE HUMAN CIRCULATION: ELUCIDATING THE HEMODYNAMICS OF THE HYBRID NORWOOD PALLIATIVE TREATMENT AND EFFECTS OF THE REVERSE BLALOCK-TAUSSIG SHUNT PLACEMENT AND DIAMETER.
- Creator
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Ceballos, Andres, Kassab, Alain, Bai, Yuanli, Deng, Weiwei, DeCampli, William, Divo, Eduardo, University of Central Florida
- Abstract / Description
-
The Hybrid Norwood (HN) is a relatively new first stage procedure for neonates with Hypoplastic Left Heart Syndrome (HLHS), in which a sustainable univentricular circulation is established in a less invasive manner than with the standard procedure. A computational multiscale model of such HLHS circulation following the HN procedure was used to obtain detailed hemodynamics. Implementation of a reverse-BT shunt (RBTS), a synthetic bypass from the main pulmonary to the innominate artery placed...
Show moreThe Hybrid Norwood (HN) is a relatively new first stage procedure for neonates with Hypoplastic Left Heart Syndrome (HLHS), in which a sustainable univentricular circulation is established in a less invasive manner than with the standard procedure. A computational multiscale model of such HLHS circulation following the HN procedure was used to obtain detailed hemodynamics. Implementation of a reverse-BT shunt (RBTS), a synthetic bypass from the main pulmonary to the innominate artery placed to counteract aortic arch stenosis, and its effects on local and global hemodynamics were studied.A synthetic and a 3D reconstructed, patient derived anatomy after the HN procedure were utilized, with varying degrees of distal arch obstruction, or stenosis, (nominal and 90% reduction in lumen) and varying RBTS diameters (3.0, 3.5, 4.0 mm). A closed lumped parameter model (LPM) for the peripheral or distal circulation coupled to a 3D Computational Fluid Dynamics (CFD) model that allows detailed description of the local hemodynamics was created for each anatomy. The implementation of the RBTS in any of the chosen diameters under severe stenosis resulted in a restoration of arterial perfusion to near-nominal levels. Shunt flow velocity, vorticity, and overall wall shear stress levels are inverse functions of shunt diameter, while shunt perfusion and systemic oxygen delivery correlates positively with diameter. No correlation of shunt diameter with helicity was recorded.In the setting of the hybrid Norwood circulation, our results suggest: (1) the 4.0mm RBTS may be more thrombogenic when implemented in the absence of severe arch stenosis and (2) the 3.0mm and 3.5mm RBTS may be a more suitable alternative, with preference to the latter since it provides similar hemodynamics at lower levels of wall shear stress.
Show less - Date Issued
- 2015
- Identifier
- CFE0005772, ucf:50068
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005772
