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THE RESPONSE OF A GENERAL CIRCULATION CLIMATE MODEL TOHIGH LATITUDE FRESHWATER FORCING IN THE ATLANTIC BASINWITH RESPECT TOTROPICAL CYCLONE-LIKE VORTICES
Title
THE RESPONSE OF A GENERAL CIRCULATION CLIMATE MODEL TOHIGH LATITUDE FRESHWATER FORCING IN THE ATLANTIC BASINWITH RESPECT TOTROPICAL CYCLONE-LIKE VORTICES.
Creator
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.
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Date Issued
2007
Identifier
CFE0001810, ucf:47339
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0001810
IMAGE QUALITY ANALYSIS USING GLCM
Title
IMAGE QUALITY ANALYSIS USING GLCM.
Creator
Gadkari, Dhanashree, Clarke, Thomas, University of Central Florida
Abstract / Description
Gray level co-occurrence matrix has proven to be a powerful basis for use in texture classification. Various textural parameters calculated from the gray level co-occurrence matrix help understand the details about the overall image content. The aim of this research is to investigate the use of the gray level co-occurrence matrix technique as an absolute image quality metric. The underlying hypothesis is that image quality can be determined by a comparative process in which a sequence of...
Show moreGray level co-occurrence matrix has proven to be a powerful basis for use in texture classification. Various textural parameters calculated from the gray level co-occurrence matrix help understand the details about the overall image content. The aim of this research is to investigate the use of the gray level co-occurrence matrix technique as an absolute image quality metric. The underlying hypothesis is that image quality can be determined by a comparative process in which a sequence of images is compared to each other to determine the point of diminishing returns. An attempt is made to study whether the curve of image textural features versus image memory sizes can be used to decide the optimal image size. The approach used digitized images that were stored at several levels of compression. GLCM proves to be a good discriminator in studying different images however no such claim can be made for image quality. Hence the search for the best image quality metric continues.
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Date Issued
2004
Identifier
CFE0000273, ucf:46223
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0000273
USING MODELING AND SIMULATION TO EVALUATE DISEASE CONTROL MEASURES
Title
USING MODELING AND SIMULATION TO EVALUATE DISEASE CONTROL MEASURES.
Creator
Atkins, Tracy, Clarke, Thomas, University of Central Florida
Abstract / Description
This dissertation introduced several issues concerning the analysis of diseases by showing how modeling and simulation could be used to assist in creating health policy by estimating the effects of such policies. The first question posed was how would education, vaccination and a combination of these two programs effect the possible outbreak of meningitis on a college campus. After creating a model representative of the transmission dynamics of meningitis and establishing parameter values...
Show moreThis dissertation introduced several issues concerning the analysis of diseases by showing how modeling and simulation could be used to assist in creating health policy by estimating the effects of such policies. The first question posed was how would education, vaccination and a combination of these two programs effect the possible outbreak of meningitis on a college campus. After creating a model representative of the transmission dynamics of meningitis and establishing parameter values characteristic of the University of Central Florida main campus, the results of a deterministic model were presented in several forms. The result of this model was the combination of education and vaccination would eliminate the possibility of an epidemic on our campus. Next, we used simulation to evaluate how quarantine and treatment would affect an outbreak of influenza on the same population. A mathematical model was created specific to influenza on the UCF campus. Numerical results from this model were then presented in tabular and graphical form. The results comparing the simulations for quarantine and treatment show the best course of action would be to enact a quarantine policy on the campus thus reducing the maximum number of infected while increasing the time to reach this peak. Finally, we addressed the issue of performing the analysis stochastically versus deterministically. Additional models were created with the progression of the disease occurring by chance. Statistical analysis was done on the mean of 100 stochastic simulation runs comparing that value to the one deterministic outcome. The results for this analysis were inconclusive, as the results for meningitis were comparable while those for influenza appeared to be different.
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Date Issued
2010
Identifier
CFE0003232, ucf:48535
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0003232
A WEARABLE HEAD-MOUNTED PROJECTION DISPLAY
Title
A WEARABLE HEAD-MOUNTED PROJECTION DISPLAY.
Creator
Martins, Ricardo, Clarke, Thomas, University of Central Florida
Abstract / Description
Conventional head-mounted projection displays (HMPDs) contain of a pair of miniature projection lenses, beamsplitters, and miniature displays mounted on the helmet, as well as a retro-reflective screen placed strategically in the environment. We have extened the HMPD technology integrating the screen into a fully mobile embodiment. Some initial efforts of demonstrating this technology has been captured followed by an investigation of the diffraction effects versus image degradation caused by...
Show moreConventional head-mounted projection displays (HMPDs) contain of a pair of miniature projection lenses, beamsplitters, and miniature displays mounted on the helmet, as well as a retro-reflective screen placed strategically in the environment. We have extened the HMPD technology integrating the screen into a fully mobile embodiment. Some initial efforts of demonstrating this technology has been captured followed by an investigation of the diffraction effects versus image degradation caused by integrating the retro-reflective screen within the HMPD. The key contribution of this research is the conception and development of a mobile-HMPD (M-HMPD). We have included an extensive analysis of macro- and microscopic properties that encompass the retro-reflective screen. Furthermore, an evaluation of the overall performance of the optics will be assessed in both object space for the optical designer and visual space for the possible users of this technology. This research effort will also be focused on conceiving a mobile M-HMPD aimed for dual indoor/outdoor applications. The M-HMPD shares the known advantage such as ultra-lightweight optics (i.e. 8g per eye), unperceptible distortion (i.e. ≤ 2.5%), and lightweight headset (i.e. ≤ 2.5 lbs) compared with eyepiece type head-mounted displays (HMDs) of equal eye relief and field of view. In addition, the M-HMPD also presents an advantage over the preexisting HMPD in that it does not require a retro-reflective screen placed strategically in the environment. This newly developed M-HMPD has the ability to project clear images at three different locations within near- or far-field observation depths without loss of image quality. This particular M-HMPD embodiment was targeted to mixed reality, augmented reality, and wearable display applications.
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Date Issued
2010
Identifier
CFE0003431, ucf:48390
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0003431
A Fitness Function Elimination Theory for Blackbox Optimization and Problem Class Learning
Title
A Fitness Function Elimination Theory for Blackbox Optimization and Problem Class Learning.
Creator
Anil, Gautham, Wu, Annie, Wiegand, Rudolf, Stanley, Kenneth, Clarke, Thomas, Jansen, Thomas, University of Central Florida
Abstract / Description
The modern view of optimization is that optimization algorithms are not designed in a vacuum, but can make use of information regarding the broad class of objective functions from which a problem instance is drawn. Using this knowledge, we want to design optimization algorithms that execute quickly (efficiency), solve the objective function with minimal samples (performance), and are applicable over a wide range of problems (abstraction). However, we present a new theory for blackbox...
Show moreThe modern view of optimization is that optimization algorithms are not designed in a vacuum, but can make use of information regarding the broad class of objective functions from which a problem instance is drawn. Using this knowledge, we want to design optimization algorithms that execute quickly (efficiency), solve the objective function with minimal samples (performance), and are applicable over a wide range of problems (abstraction). However, we present a new theory for blackbox optimization from which, we conclude that of these three desired characteristics, only two can be maximized by any algorithm.We put forward an alternate view of optimization where we use knowledge about the problem class and samples from the problem instance to identify which problem instances from the class are being solved. From this Elimination of Fitness Functions approach, an idealized optimization algorithm that minimizes sample counts over any problem class, given complete knowledge about the class, is designed. This theory allows us to learn more about the difficulty of various problems, and we are able to use it to develop problem complexity bounds.We present general methods to model this algorithm over a particular problem class and gain efficiency at the cost of specifically targeting that class. This is demonstrated over the Generalized Leading-Ones problem and a generalization called LO**, and efficient algorithms with optimal performance are derived and analyzed. We also tighten existing bounds for LO***. Additionally, we present a probabilistic framework based on our Elimination of Fitness Functions approach that clarifies how one can ideally learn about the problem class we face from the objective functions. This problem learning increases the performance of an optimization algorithm at the cost of abstraction.In the context of this theory, we re-examine the blackbox framework as an algorithm design framework and suggest several improvements to existing methods, including incorporating problem learning, not being restricted to blackbox framework and building parametrized algorithms. We feel that this theory and our recommendations will help a practitioner make substantially better use of all that is available in typical practical optimization algorithm design scenarios.
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Date Issued
2012
Identifier
CFE0004511, ucf:49268
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004511
Inquiry as Practice for Continuous Improvement: A Framework for the Curricular Redesign of the Education Doctorate in Curriculum and Instruction Research Continuum at the University of Central Florida.
Title
Inquiry as Practice for Continuous Improvement: A Framework for the Curricular Redesign of the Education Doctorate in Curriculum and Instruction Research Continuum at the University of Central Florida.
Creator
Clark, Paola, Boote, David, Vitale, Thomas, Hopp, Carolyn, Swan, Bonnie, University of Central Florida
Abstract / Description
This design-based research study was conducted at the University of Central Florida with the aim of informing the Education Doctorate in Curriculum and Instruction research course sequence within the College of Education and Human Performance. The main purpose of this dissertation was to enhance and enrich the Ed.D. in Curriculum and Instruction research continuum courses to ensure that they support the use of applied research and practical theory as central to the development of scholarly...
Show moreThis design-based research study was conducted at the University of Central Florida with the aim of informing the Education Doctorate in Curriculum and Instruction research course sequence within the College of Education and Human Performance. The main purpose of this dissertation was to enhance and enrich the Ed.D. in Curriculum and Instruction research continuum courses to ensure that they support the use of applied research and practical theory as central to the development of scholarly practitioners. In order to fulfill its purpose, this study addressed three main goals: clarifying the Ed.D. in Curriculum and Instruction program goals, objectives, and research continuum learning outcomes; developing research course sequence curriculum maps; and redesigning sample curriculum units for individual research courses.The curriculum mapping and redesign process was supported by research-based design choices in alignment with the practice-oriented nature of the program. These design choices included the Carnegie Project on the Education Doctorate Working Principles and Design Concepts, in particular the use of Inquiry as Practice as the main redesign framework in combination with improvement science principles. These frameworks were first used as foundations to clarify the Ed.D. in Curriculum and Instruction program goal and overall objectives. Later, user-centered design principles were applied to create faculty and student personas in order to inform the redefinition of individual research course learning outcomes. In addition, the frameworks were used to create alignment matrices and demonstrate where they supported each of the program objectives. This iterative process was carried out simultaneously with the course curriculum map redesign for each of the research continuum courses using backward design principles, the spiral curriculum model, and taking into consideration the most suitable instructional modality for learning outcomes, including the best suited education technology choices. Further, some proposed sample course units were developed in greater detail utilizing Universal Design for Learning principles and the prioritization of learning outcomes. Course contents were selected based on cognitive and reasoning learning theories pertaining to mixed method courses for professional practitioners.The developed prototypes support the continuous Ed.D. in Curriculum and Instruction curriculum redesign efforts of the program and College of Education and Human Performance at the University of Central Florida and clearly distinguish the Ed.D. in Curriculum and Instruction program from traditional, research-based doctorates. Similarly, at the national level, this study also sought to benefit other CPED-influenced professional practice programs, as they also consider the careful redesign of their research or inquiry sequences to define their programs as ones that fully address the needs of advanced professional educators. Acknowledging the limitations of this study, further studies should identifying the motivational, cognitive, and organizational causes affecting student learning outcomes. Implementing and evaluating the prototypes developed to ensure their effectiveness in preparing scholarly practitioners to act as agents of change in their professional practices.
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Date Issued
2016
Identifier
CFE0006285, ucf:51585
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006285
An approach to improve the failure rate model of a solid state laser by utilizing the Physics of Failure Methodology.
Title
An approach to improve the failure rate model of a solid state laser by utilizing the Physics of Failure Methodology.
Creator
Thompson, Omar, Kincaid, John, Bass, Michael, Clarke, Thomas, Wiegand, Rudolf, Shumaker, Randall, Bass, Michael, University of Central Florida
Abstract / Description
The ability to predict the failure rate of any military laser is very critical. In-field laser usage does not support the troubleshooting and repairing of a complex electro optical system. The only published laser failure rate model was last updated by the Department of Defense in 1975. Consequently, the failure rate predicted is inaccurate due to model deficiencies. This dissertatiodatn has developed a laser failure rate model for diode pumped lasers with improved failure rate prediction...
Show moreThe ability to predict the failure rate of any military laser is very critical. In-field laser usage does not support the troubleshooting and repairing of a complex electro optical system. The only published laser failure rate model was last updated by the Department of Defense in 1975. Consequently, the failure rate predicted is inaccurate due to model deficiencies. This dissertatiodatn has developed a laser failure rate model for diode pumped lasers with improved failure rate prediction accuracy. The model has surpassed the capabilities of the Department of Defense model by the inclusion of key performance attributes that are currently not taken into account. The scope of work completed was based on a tailored Physics of Failure methodology. The research approach implemented was: 1. Integration of Failure Mode and Effects Analysis to evaluate deployed laser failure. 2. Beam simulation for alignment tolerance analysis. 3. Thermal and vibration effects analysis on laser performance. 4. Analysis and development of a methodology to represent a resonator failure rate model. A secondary contribution of this research effort is supporting the update of the current laser failure rate model. The success of revising the current model relies on leveraging the work of other organizations in the area of failure rate modeling and reliability predictions.
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Date Issued
2011
Identifier
CFE0004587, ucf:49214
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004587