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Title: NAVIGATION AIDS IN ROUTE TRAINING: INCREASE NAVIGATION SPEED, DECREASE ROUTE RETENTION?.
Creator: Holmquist, John, Lee, Gene, University of Central Florida
Abstract / Description: In the case of one car following another to a destination, it is very effective at getting the second vehicle to the destination quickly; however, the driver of the second car may not learn the route. Yet, for individuals, such as firefighters, law enforcement, and military personnel, it is imperative that a route be learned quickly and accurately and that an awareness of the situation is maintained while they traverse the given route. This leads to three questions, (a) will navigation aids...
Show moreIn the case of one car following another to a destination, it is very effective at getting the second vehicle to the destination quickly; however, the driver of the second car may not learn the route. Yet, for individuals, such as firefighters, law enforcement, and military personnel, it is imperative that a route be learned quickly and accurately and that an awareness of the situation is maintained while they traverse the given route. This leads to three questions, (a) will navigation aids affect initial route navigation; (b) will navigation aids affect retention; and (c) will navigation aids affect situation awareness while en route? The hypotheses of this study were that navigation aids would significantly increase the speed at which a person can initially navigate a route, but the use of the aids would significantly decrease the retention of the route navigated. The findings of this study support the hypotheses. The results suggest that participants that followed a confederate and participants that were given verbal directions were quicker and made fewer errors than participants that reviewed a map or initially figured the route out on their own (control group). The study also showed that as the participants navigated the route for a second time with no navigational assistance, the ones that reviewed a map or that were in the control group outperformed participants that initially had a confederate to follow or were given verbal directions their first time through. Finally, no real effects were found on the participants' situation awareness during the retention portion of the study.
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Date Issued: 2005
Identifier: CFE0000520, ucf:46453
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000520

Title: ON MODELING HIV INFECTION OF CD4+ T CELLS.
Creator: Comerford, Amy, Mohapatra, Ram, University of Central Florida
Abstract / Description: We examine an early model for the interaction of HIV with CD4+ T cells in vivo and define possible parameters and effects of said parameters on the model. We then examine a newer, more simplified model for the interaction of HIV with CD4+ T cells that also considers four populations: uninfected T cells, latently infected T cells, actively infected T cells, and free virus. The stability of both the disease free steady state and the endemically infected steady state are examined utilizing...
Show moreWe examine an early model for the interaction of HIV with CD4+ T cells in vivo and define possible parameters and effects of said parameters on the model. We then examine a newer, more simplified model for the interaction of HIV with CD4+ T cells that also considers four populations: uninfected T cells, latently infected T cells, actively infected T cells, and free virus. The stability of both the disease free steady state and the endemically infected steady state are examined utilizing standard methods and the Routh-Hurwitz criteria. We show that if N, the number of infectious virions produced per actively infected T cell, is less than a critical value, , then the uninfected state is the only steady state in the non negative orthant, and this state is stable. We establish an expression for . If , then the uninfected steady state is unstable, and the endemically infected state can be stable or unstable, depending on the value of the parameters utilized.
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Date Issued: 2006
Identifier: CFE0001093, ucf:46769
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001093

Title: USING THE SOFTWARE ADAPTER TO CONNECT LEGACY SIMULATION MODELS TO THE RTI.
Creator: Rachapalli, Deepak Kumar, Rabelo, Luis, University of Central Florida
Abstract / Description: The establishment of a network of persistent shared simulations depends on the presence of a robust standard for communicating state information between those simulations. The High Level Architecture (HLA) can serve as the basis for such a standard. While the HLA is architecture, not software, use of Run Time Infrastructure (RTI) software is required to support operations of a federation execution. The integration of RTI with existing simulation models is complex and requires a lot of...
Show moreThe establishment of a network of persistent shared simulations depends on the presence of a robust standard for communicating state information between those simulations. The High Level Architecture (HLA) can serve as the basis for such a standard. While the HLA is architecture, not software, use of Run Time Infrastructure (RTI) software is required to support operations of a federation execution. The integration of RTI with existing simulation models is complex and requires a lot of expertise. This thesis implements a less complex and effective interaction between a legacy simulation model and RTI using a middleware tool known as Distributed Manufacturing Simulation (DMS) adapter. Shuttle Model, an Arena based discrete-event simulation model for shuttle operations, is connected to the RTI using the DMS adapter. The adapter provides a set of functions that are to be incorporated within the Shuttle Model, in a procedural manner, in order to connect to RTI. This thesis presents the procedure when the Shuttle Model connects to the RTI, to communicate with the Scrub Model for approval of its shuttle's launch.
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Date Issued: 2006
Identifier: CFE0000922, ucf:46764
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000922

Title: PREDICTING RISKS OF INVASION OF CAULERPA SPECIES IN FLORIDA.
Creator: Glardon, Christian, Walters, Linda, University of Central Florida
Abstract / Description: Invasions of exotic species are one of the primary causes of biodiversity loss on our planet (National Research Council 1995). In the marine environment, all habitat types including estuaries, coral reefs, mud flats, and rocky intertidal shorelines have been impacted (e.g. Bertness et al. 2001). Recently, the topic of invasive species has caught the public's attention. In particular, there is worldwide concern about the aquarium strain of the green alga Caulerpa taxifolia (Vahl) C. Agardh...
Show moreInvasions of exotic species are one of the primary causes of biodiversity loss on our planet (National Research Council 1995). In the marine environment, all habitat types including estuaries, coral reefs, mud flats, and rocky intertidal shorelines have been impacted (e.g. Bertness et al. 2001). Recently, the topic of invasive species has caught the public's attention. In particular, there is worldwide concern about the aquarium strain of the green alga Caulerpa taxifolia (Vahl) C. Agardh that was introduced to the Mediterranean Sea in 1984 from the Monaco Oceanographic Museum. Since that time, it has flourished in thousands of hectares of near-shore waters. More recently, C. taxifolia has invaded southern Californian and Australian waters. Since the waters of Florida are similar to the waters of the Mediterranean Sea and other invasive sites my study will focus on determining potential invasion locations in Florida. I will look at the present distribution of C. taxifolia - native strain in Florida as well as the distribution of the whole genus around the state. During this study, I address three questions: 1) What is the current distribution of Caulerpa spp. in Florida? 2) Can I predict the location of potential Caulerpa spp. invasions using a set of environmental parameters and correlate them to the occurrence of the algae with the support of Geographic Information System (GIS) maps? 3) Using the results of part two, is there an ecological preferred environment for one or all Caulerpa spp. in Florida? To answer these questions, I surveyed 24 areas in each of 6 zones chosen in a stratified manner along the Floridian coastline to evaluate the association of potential indicators Caulerpa. Latitude, presence or absence of seagrass beds, human population density, and proximity to marinas were chosen as the 4 parameters expected to correlate to Caulerpa occurrences. A logistic regression model assessing the association of Caulerpa occurrence with measured variables has been developed to predict current and future probabilities of Caulerpa spp. presence throughout the state. Fourteen different species of Caulerpa spp. were found in 26 of the 132 sites visited. There was a positive correlation between Caulerpa spp. and seagrass beds presence and proximity to marinas. There was a negative correlation with latitude and human population density. C. taxifolia – aquarium strain wasn't found. Percent correct for our model was of 61.5% for presence and 98.1% for absence. This prediction model will allow us to focus on particular areas for future surveys.
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Date Issued: 2006
Identifier: CFE0001041, ucf:46796
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001041

Title: ADAPTING THE MODIFIED CAM CLAY CONSTITUTIVE MODEL TO THE COMPUTATIONAL ANALYSIS OF DENSE GRANULAR SOILS.
Creator: Arvelo, Jose, Chopra, Manoj, University of Central Florida
Abstract / Description: The computational constitutive Modified Cam Clay Model (MCCM) was developed at Cambridge to study the behavior of clays and has been proven to be effective. In this study, this model is extended to the case of dense sands to analyze the accuracy of the stress-strain behavior. This analysis is based on triaxial test data applied to remolded and compacted sand samples under drained conditions. The laboratory triaxial tests were performed by the Florida Department of Transportation to research...
Show moreThe computational constitutive Modified Cam Clay Model (MCCM) was developed at Cambridge to study the behavior of clays and has been proven to be effective. In this study, this model is extended to the case of dense sands to analyze the accuracy of the stress-strain behavior. This analysis is based on triaxial test data applied to remolded and compacted sand samples under drained conditions. The laboratory triaxial tests were performed by the Florida Department of Transportation to research the permeability effect in sandy soils compacted up to 95% of maximum unit weight at the optimum moisture content. Each soil sample was tested using different stress paths. In addition, these data were also used to obtain the soil parameters. These soil parameters are used as input data for the Modified Cam Clay Model. Moreover, a computer program in MATLAB was developed based on the MCCM constitutive theory and application in order to predict the stress-strain response for overconsolidated soils under drained condition. Based on observations of the qualitative behavior of these soils, a modification is proposed in this thesis to the original constitutive model to improve the predicted stress-strain behavior. The results of the computer program are typically presented in the deviatoric stress versus shear strain and the stress path plane (deviatoric stress versus mean effective stress). These are the principal plots used for the behavior prediction of soil specimens. Furthermore, the results of the computer program were compared to the laboratory triaxial test data. In general, it is may be concluded that, MCCM with some modification, is applicable to dense sands.
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Date Issued: 2005
Identifier: CFE0000894, ucf:46630
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000894

Title: AN OPTIMIZED KINETICS MODEL FOR OH CHEMILUMINESCENCE AT HIGH TEMPERATURES AND ATMOSPHERIC PRESSURES.
Creator: Hall, Joel, Petersen, Eric, University of Central Florida
Abstract / Description: Chemiluminescence from the OH(A-X) transition near 307 nm is a commonly used diagnostic in combustion applications such as flame chemistry, shock-tube experiments, and reacting-flow visualization. Measurements of the chemiluminescent intensity provide a simple, cost-effective, non-intrusive look at the combustion environment. The presence of the ultra-violet emission is often used as an indicator of the flame zone in practical combustion systems, and its intensity may be correlated to the...
Show moreChemiluminescence from the OH(A-X) transition near 307 nm is a commonly used diagnostic in combustion applications such as flame chemistry, shock-tube experiments, and reacting-flow visualization. Measurements of the chemiluminescent intensity provide a simple, cost-effective, non-intrusive look at the combustion environment. The presence of the ultra-violet emission is often used as an indicator of the flame zone in practical combustion systems, and its intensity may be correlated to the temperature distribution or other parameters of interest. While absolute measurements of the ground-state OH(X) concentrations are well-defined, there is no elementary relation between emission from the electronically excited state (OH*) and its absolute concentration. Thus, to enable quantitative emission measurements, a kinetics model has been assembled and optimized to predict OH* formation and quenching at combustion conditions. Shock-tube experiments were conducted in mixtures of H2/O2/Ar, CH4/O2/Ar and CH4/H2/O2/Ar with high levels of argon dilution (> 98%). Elementary reactions to model OH*, along with initial estimates of their rate coefficients, were taken from the literature. The important formation steps follow. CH + O2 = OH* + CO (R0) H + O + M = OH* + M (R1) H + OH + OH = OH* + H2O (R2) Sensitivity analyses were performed to design experiments at conditions most sensitive to the formation reactions. A fitting routine was developed to express the key rate parameters as a function of a single rate, k1 at the reference temperature (1490 K). With all rates so expressed, H2/CH4 mixtures were designed to uniquely determine the value of k1 at the reference temperature, from which the remaining rate parameters were calculated. Quenching rates were fixed at their literature values. Comparisons to predictions of previously available models show marked improvement relative to the new shock-tube data. An approach for using this work in the calibration of further measurements is outlined taking examples from a recent ethane oxidation study. The new model qualitatively matches the experimental data over the range of conditions studied and provides quantitative results applicable to real combustion environments, containing higher-order hydrocarbon fuels and lower levels of dilution in air.
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Date Issued: 2005
Identifier: CFE0000888, ucf:46642
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000888

Title: THE DEVELOPMENT OF A FUZZY MODEL TO QUANTIFY TRAINING ANDEDUCATIONAL FACTORS AND THE RESULTING IMPACT ON STUDENT SUCCESSAND LEARNING.
Creator: Butler, Chandre, McCauley-Bell, Pamela, University of Central Florida
Abstract / Description: The utilization of fuzzy mathematical modeling for quantification of the quality of training and educational delivery is an innovative application that can result in measurable and repeatable results. This research was designed to apply proven quantification techniques and Industrial Engineering methodologies to a nontraditional environment. The outcomes of this research provide the foundation, initial steps and preliminary validation for the development of a systematic fuzzy theoretical...
Show moreThe utilization of fuzzy mathematical modeling for quantification of the quality of training and educational delivery is an innovative application that can result in measurable and repeatable results. This research was designed to apply proven quantification techniques and Industrial Engineering methodologies to a nontraditional environment. The outcomes of this research provide the foundation, initial steps and preliminary validation for the development of a systematic fuzzy theoretical model to be applied for the quantification of various areas within training and education delivery. The test bed for this methodology is Orange County Public School system, the twelfth largest school district in the nation. The organizational and operational factors of a large school district are highly compatible with Systems Engineering concepts. The debate over education reform has drawn from referenced areas within the Industrial Engineering community including quality, continuous improvement, benchmarking and metrics development, data analysis, and scientific/systemic justification requirements. In spite of these applications, the literature does not reflect a consistent and broad application of these techniques in addressing the evaluation and quantification of educational delivery systems. This research draws on the previously listed areas within Industrial Engineering to apply these techniques to enhance the understanding and promote quantification of the multiple factors acting on the educational delivery system. The importance of addressing these issues is a national concern given the significant changes in the United States educational delivery system. For example, over the past 40 years there has been a more than three-hundred percent increase in per-pupil appropriations yet the academic performance gains have been limited and the quantification and measurement of those gains is even more limited. This body of work willidentify the systems, sub-systems, system factors, and factor degrees of existence necessary to quantify and measure these performance changes. Finally, the research will quantify the inputs and produce a model that provides a numeric value that represents the condition of the system and various subsystems of an educational system.
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Date Issued: 2005
Identifier: CFE0000890, ucf:46640
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000890

Title: EFFECTS OF CONTENT AUGMENTATION STRATEGIES IN AN INSTRUCTIONAL VIRTUAL ENVIRONMENT.
Creator: Hamilton, Roger, Kincaid, J. Peter, University of Central Florida
Abstract / Description: Content augmentation strategies (CAS) are instructional methods which specify the overlaying of content objects by content augmentation objects in order to increase the effectiveness and efficiency of instruction. The goals of this research were to build a comprehensive framework around CASs, determine the experimental effects of CASs in an instructional virtual environment (VE), and make recommendations regarding the employment and further study of CASs in instructional virtual environments....
Show moreContent augmentation strategies (CAS) are instructional methods which specify the overlaying of content objects by content augmentation objects in order to increase the effectiveness and efficiency of instruction. The goals of this research were to build a comprehensive framework around CASs, determine the experimental effects of CASs in an instructional virtual environment (VE), and make recommendations regarding the employment and further study of CASs in instructional virtual environments. The VE experiment examined the effectiveness and efficiency impact of six different content augmentation strategies which overlayed different content augmentation objects onto four immersive VE scenarios. Sixty university students, 40 men and 20 women, executed three CAS-enhanced training missions and one no-CAS test mission. The task involved the recall and correct application of specific rules for three subtasks of a military helicopter landing zone scouting mission. The strategies included a no-strategy control condition, an arrow condition, an audio coaching condition, a text coaching condition, an arrow plus audio coaching condition, and an arrow plus text coaching condition. Statistical and decision analyses were conducted on the effectiveness and efficiency performance data. Statistically significant differences were found which supported the general superiority of the audio content augmentation strategy for these tasks. This dissertation may be the first use of a decision analysis approach for analyzing the results of behavioral data for instructional design decisions. The decision analysis approach used decision trees, simulation and optimization to obtain content augmentation strategy rankings. As this approach is normally used for course of action analysis and comparing alternative system configurations, the validity of this approach in this context has yet to be determined. The decision analysis approach obtained plausible and similar, but not identical recommendations to the statistical approach. The decision analysis approach may constitute a limited instantiation of a proposed optimal stimulus set instructional design model which conceptually framed the experiment. Training guideline recommendations, experimental procedure recommendations, and a comprehensive framework for future research are also presented.
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Date Issued: 2005
Identifier: CFE0000884, ucf:46638
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000884

Title: EFFECTIVENESS AND KINETICS OF FERRATE AS ADISINFECTANT FOR BALLAST WATER.
Creator: Jessen, Andrea, Randall, Andrew, University of Central Florida
Abstract / Description: The introduction of aquatic nuisance species (ANS) and bacterial pathogens from discharge of ballast water by sea-faring vessels is an ongoing problem that threatens ecosystems and human health. This study investigates the disinfecting capability of ferrate in a marine environment on several organisms listed in international standards for ballast water management. Organisms were grown in a saline solution and were treated with dosages of ferrate ranging from 0.25-5.0 mg/l. A ferrate dose of 5...
Show moreThe introduction of aquatic nuisance species (ANS) and bacterial pathogens from discharge of ballast water by sea-faring vessels is an ongoing problem that threatens ecosystems and human health. This study investigates the disinfecting capability of ferrate in a marine environment on several organisms listed in international standards for ballast water management. Organisms were grown in a saline solution and were treated with dosages of ferrate ranging from 0.25-5.0 mg/l. A ferrate dose of 5 mg/l resulted in almost complete kill for all organisms tested. Smaller dosages have also been very effective, particularly if all organic material from the nutrient broth used to cultivate them is removed by washing the cells with saline solution. Ferrate appears to act very quickly, with tailing occurring after about 5-15 minutes. Analyses of the data with the CT approach, the Chick-Watson and Hom's models, and an oxidant demand equation derived from equations recommended by the Water Environment Federation (WEF) are in good agreement that ferrate concentration is more important than contact time. The Hom's model appeared to most accurately represent the action of ferrate on these organisms. Salinity and pH did not adversely affect results, and regrowth was not a problem. Two measures to reduce clumping did not eliminate the observed tailing effect, suggesting a different mechanism for this phenomena. These preliminary tests indicate that ferrate could be a very effective disinfectant in the treatment of ballast water, and the short half-life of ferrate is an advantage, since the ballast water is subsequently released into the environment.
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Date Issued: 2006
Identifier: CFE0001287, ucf:46891
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001287

Title: IDENTIFYING FACTORS THAT INFLUENCE GENDER DISPARITIES IN PHYSICIAN INCOME: IMPLICATIONS FOR PUBLIC POLICY.
Creator: Bolyard, Wendy, Wan, Thomas, University of Central Florida
Abstract / Description: Research has shown that female physicians continue to earn less than their male counterparts. From both social justice and feminist perspectives, laws requiring equal pay should provide just income for females as compared to males. However, the literature continues to indicate that in general females earn less than males, a trend that is also true for physicians. Theoretically informed postulates are measured here with structural equation modeling to test the influence of the unique latent...
Show moreResearch has shown that female physicians continue to earn less than their male counterparts. From both social justice and feminist perspectives, laws requiring equal pay should provide just income for females as compared to males. However, the literature continues to indicate that in general females earn less than males, a trend that is also true for physicians. Theoretically informed postulates are measured here with structural equation modeling to test the influence of the unique latent construct "specialization" on the income gap while controlling for demographic and contextual variables. The analysis tests the assumption that the influence of specialization is the same for females and males. If the influence of specialization and other variables differs by gender, gender bias in physician income may be conceptually implied. The study uses three waves of data from the Community Tracking Study Physician Survey (CTS). The study finds an income gap between females and males in three waves of the CTS. Gini coefficients show females continue to experience greater income inequality than males, with the Lorenz curves for males being closer to the equality lines. Using 1999 income data, there is a statistically significant income gap between female and male physicians when controlling for weeks worked. Information Technology (IT) use was found to be the most reliable construct measuring the unique latent variable specialization. Structural equation modeling showed indicators of specialization have an influence on the income gap. The variables in the CTS Physician Survey made for a poor construct that failed to measure specialization as a uni-dimensional construct. The variables that influence the income gap were different for females than for males. As policy makers revise or create better laws to protect income equality, gender differences must be taken into consideration.
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Date Issued: 2006
Identifier: CFE0001245, ucf:46909
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001245

Title: SMART MATERIAL ACTUATION AND MORPHING FOR UNMANNED AIRCRAFT SYSTEMS.
Creator: Da Silva Lima, Caio H, Kauffman, Jeffrey L., University of Central Florida
Abstract / Description: The intent of this thesis is to outline the design, analysis, and characterization of an axially compressed piezocomposite actuator and, in particular, to determine the correlation and accuracy of two models used to predict deflection of an axially compressed piezocomposite bimorph. Restrictions in material properties lead to vehicle inefficiencies caused by the discontinuous geometry of deflected control surfaces in unmanned aircraft systems. This performance disadvantage in discrete control...
Show moreThe intent of this thesis is to outline the design, analysis, and characterization of an axially compressed piezocomposite actuator and, in particular, to determine the correlation and accuracy of two models used to predict deflection of an axially compressed piezocomposite bimorph. Restrictions in material properties lead to vehicle inefficiencies caused by the discontinuous geometry of deflected control surfaces in unmanned aircraft systems. This performance disadvantage in discrete control surfaces is caused in part by the sharp edges that are formed when the surface is pivoted. Flow continuity over the body of a vehicle is important in minimizing the effects of drag and, in turn, increasing aerodynamic performance. An efficient alternative to discrete control surface actuation is axially compressed piezocomposite actuation which could potentially improve the efficiency of the vehicle in all environments. Bimorph performance in angular deflection and displacement for the PA16N and MFC-M8528-P1 piezocomposites is analyzed using a Classical Laminate Plate Theory (CLPT) model and an Elastica model. Model accuracy is verified through experimental testing of a PA16N bimorph. CLPT model is shown to be accurate to within .05 mm and Elastica model is shown to be accurate to within .04 mm for axial forces below 30 N. Correlation between the mathematical models is confirmed. Experimental results for the PA16N show that a 30 N compression force applied to the bimorph can increase the maximum displacement by approximately 2.5 times the original displacement.
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Date Issued: 2016
Identifier: CFH2000095, ucf:45563
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000095

Title: RIGOROUS ANALYSIS OF AN EDGE-BASED NETWORK DISEASE MODEL.
Creator: Mai, Sabrina, Shuai, Zhisheng, University of Central Florida
Abstract / Description: Edge-based network disease models, in comparison to classic compartmental epidemiological models, better capture social factors affecting disease spread such as contact duration and social heterogeneity. We reason that there should exist infinitely many equilibria rather than only an endemic equilibrium and a disease-free equilibrium for the edge-based network disease model commonly used in the literature, as there do not exist any changes in demographic in the model. We modify the commonly...
Show moreEdge-based network disease models, in comparison to classic compartmental epidemiological models, better capture social factors affecting disease spread such as contact duration and social heterogeneity. We reason that there should exist infinitely many equilibria rather than only an endemic equilibrium and a disease-free equilibrium for the edge-based network disease model commonly used in the literature, as there do not exist any changes in demographic in the model. We modify the commonly used network model by relaxing some assumed conditions and factor in a dependency on initial conditions. We find that this modification still accounts for realistic dynamics of disease spread (such as the probability of contracting a disease based off your neighbors' susceptibility to the disease) based on the basic reproduction number. Specifically, if the basic reproduction number is below 1, then the infection dies out; while if the basic reproduction number is above 1, then there is possibility of an epidemic.
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Date Issued: 2019
Identifier: CFH2000537, ucf:45651
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000537

Title: Multiple-Case Study and Exploratory Analysis of the Implementation of Value-Added Teacher Performance Assessment on Eighth Grade Student Achievement in Ohio, Pennsylvania, and Tennessee.
Creator: Carter, James, Taylor, Rosemarye, Doherty, Walter, Hahs-Vaughn, Debbie, Gordon, William, University of Central Florida
Abstract / Description: The goal of this research was to analyze the academic impact of the implementation of the Value Added Assessment Model. The researcher analyzed the Value Added Assessment Models in the three Value Added Assessment Model states that had implemented the Value Added Assessment Model for more than five years. Additionally, the research was done by analyzing the academic impact as measured by the eighth grade reading NAEP and the eighth grade mathematics NAEP. The researcher paired the three...
Show moreThe goal of this research was to analyze the academic impact of the implementation of the Value Added Assessment Model. The researcher analyzed the Value Added Assessment Models in the three Value Added Assessment Model states that had implemented the Value Added Assessment Model for more than five years. Additionally, the research was done by analyzing the academic impact as measured by the eighth grade reading NAEP and the eighth grade mathematics NAEP. The researcher paired the three states that had implemented Value Added Assessment Model for more than five years, with three demographically matched states that had not implemented Value Added Assessment Model. The states were matched as follows: Ohio (Value Added Assessment Model implementing state) with Michigan (non Value Added Assessment Model state), Pennsylvania (Value Added Assessment Model implementing state) with Virginia (non Value Added Assessment Model state) and Tennessee (Value Added Assessment Model implementing state) with Georgia (non Value Added Assessment Model state). The mean composite scale score in NAEP from the following categories of students were compared and analyzed: 1) All students 2) White students 3) Black students 4) National School Lunch Program Eligible Students 5) National School Lunch Program Ineligible Students 6) Exceptional Education students. The results of the study indicated that the impact of Value Added Assessment Model on academic impact as measured by the eighth grade reading NAEP and the eighth grade mathematics NAEP was negligible.
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Date Issued: 2014
Identifier: CFE0005468, ucf:52862
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005468

Title: The Evolution of Shared Responsibility and Instructional Risk Communication in Brazil's Campaign against the Zika Virus.
Creator: Mauricio Soares, Rodrigo Augusto, Sellnow, Timothy, Sellnow, Deanna, Littlefield, Robert, University of Central Florida
Abstract / Description: This study provides an evaluation of instructional risk communication practices in Brazil's response to the Zika virus during the 2016/2017 campaign. The communication was instructionally focused, explaining the way the disease is transmitted, what to do if the person is infected, and characteristics of the mosquito. The authorities also tried to convince the publics that, because the mosquito breeds in everyone's houses and apartments, everyone could be part of the solution. The social,...
Show moreThis study provides an evaluation of instructional risk communication practices in Brazil's response to the Zika virus during the 2016/2017 campaign. The communication was instructionally focused, explaining the way the disease is transmitted, what to do if the person is infected, and characteristics of the mosquito. The authorities also tried to convince the publics that, because the mosquito breeds in everyone's houses and apartments, everyone could be part of the solution. The social, economic and cultural characteristics of the country, the population's low levels of health literacy, and a long-lasting government credibility problem in the country make Brazil's fight against these types of diseases considerably difficult. The IDEA model (T. Sellnow (&) D. Sellnow, 2013) was used as the theoretical grounding for the analysis. This study presents the concepts of collective efficacy and shared responsibility and recommendations for risk and crisis communication practitioners as well as government agencies with regard to engaging the population in managing this type of disease outbreak. Knowledge about how to generate and share strategic communication of this nature is increasingly important as the spread of novel diseases is increasing in frequency and intensity (Kilpatrick (&) Randolph, 2012).
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Date Issued: 2018
Identifier: CFE0007050, ucf:51974
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007050

Title: IDEOLOGICAL VOTING ON THE SUPREME COURT: AN ANALYSIS OF JUDICIAL ACTIVISM ON THE BURGER AND REHNQUIST COURTS, 1969-2004.
Creator: Larsen, Tiahna, Lanier, Drew, University of Central Florida
Abstract / Description: The influence of ideology and attitudes on the decision-making process of Supreme Court justices has been well documented, such that the attitudinal model has emerged as the dominant paradigm for understanding judicial behavior. When ideology and personal preferences seem to eclipse legal factors, such as adherence to precedent and deference to the democratically-elected branches, outcries of Ã‚Â"judicial activismÃ‚Â" have occurred. Previous studies ...
Show moreThe influence of ideology and attitudes on the decision-making process of Supreme Court justices has been well documented, such that the attitudinal model has emerged as the dominant paradigm for understanding judicial behavior. When ideology and personal preferences seem to eclipse legal factors, such as adherence to precedent and deference to the democratically-elected branches, outcries of Ã‚Â"judicial activismÃ‚Â" have occurred. Previous studies (Lindquist and Cross 2009) have operationalized judicial activism and have provided measures for studying behavior that may be considered activist (as opposed to restrainist), further supporting the premise that ideology trumps other extra-attitudinal and legal factors in the judicial decision-making process. While the attitudinal model indicates that ideology is the strongest predictor of judicial decision-making, this research will include a number of legal variables that have significantly influenced justicesÃ‚Â' votes. As previous studies have demonstrated, an integrated model that combines a number of critical variables can have more explanatory power than one that relies on attitudinal reasons alone (Banks 1999; Hurwitz and Stefko 2004; Mishler and Sheehan 1996). As such, the purpose of this research is to examine individual level decision-making of the most ideological justices on the Burger and Rehnquist Courts (1969-2004) in regards to their activist behavior to overrule legal precedents and invalidate federal statutes. This research will employ multivariate regression analysis to assess the effects of attitudinal, legal and extra-attitudinal factors in the judicial decision-making process.
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Date Issued: 2010
Identifier: CFE0003287, ucf:48531
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003287

Title: LANDFILL GAS TO ENERGY: INCENTIVES & BENEFITS.
Creator: Amini, Hamid, Reinhart, Debra, University of Central Florida
Abstract / Description: Municipal solid waste (MSW) management strategies typically include a combination of three approaches, recycling, combustion, and landfill disposal. In the US approximately 54% of the generated MSW was landfilled in 2008, mainly because of its simplicity and cost-effectiveness. However, landfills remain a major concern due to potential landfill gas (LFG) emissions, generated from the chemical and biological processes occurring in the disposed waste. The main components of LFG are methane (50...
Show moreMunicipal solid waste (MSW) management strategies typically include a combination of three approaches, recycling, combustion, and landfill disposal. In the US approximately 54% of the generated MSW was landfilled in 2008, mainly because of its simplicity and cost-effectiveness. However, landfills remain a major concern due to potential landfill gas (LFG) emissions, generated from the chemical and biological processes occurring in the disposed waste. The main components of LFG are methane (50-60%) and carbon dioxide (40-50%). Although LFG poses a threat to the environment, if managed properly it is a valuable energy resource due to the methane content. Currently there are over 550 active LFG to energy (LFGTE) facilities in the US, producing renewable energy from LFG. A major challenge in designing/operating a LFGTE facility is the uncertainty in LFG generation rate predictions. LFG generation rates are currently estimated using models that are dependent upon the waste disposal history, moisture content, cover type, and gas collection system, which are associated with significant uncertainties. The objectives of this research were to: (1) Evaluate various approaches of estimating LFG generation and to quantify the uncertainty of the model outcomes based on case-study analysis, (2) Present a methodology to predict long-term LFGTE potential under various operating practices on a regional scale, and (3) Investigate costs and benefits of emitting vs. collecting LFG emissions with regards to operation strategies and regulations. The first-order empirical model appeared to be insensitive to the approach taken in quantifying the model parameters, suggesting that the model may be inadequate to accurately describe LFG generation and collection. The uncertainty values for the model were, in general, at their lowest within five years after waste placement ended. Because of the exponential nature, the uncertainty increased as LFG generation declined to low values decades after the end of waste placement. A methodology was presented to estimate LFGTE potential on a regional scale over a 25-year timeframe with consideration of modeling uncertainties. The methodology was demonstrated for the US state of Florida, and showed that Florida could increase the annual LFGTE production by more than threefold by 2035 through installation of LFGTE facilities at all landfills. Results showed that diverting food waste could significantly reduce fugitive LFG emissions, while having minimal effect on the LFGTE potential. Estimates showed that with enhanced landfill operation and energy production practices, LFGTE power density could be comparable to technologies such as wind, tidal, and geothermal. More aggressive operations must be considered to avoid fugitive LFG emissions, which could significantly affect the economic viability of landfills. With little economic motivation for US landfill owners to voluntarily reduce fugitive emissions, regulations are necessary to increase the cost of emitting GHGs. In light of the recent economic recession, it is not likely that a carbon tax will be established; while a carbon trading program will enforce emission caps and provide a tool to offset some costs and improve emission-reduction systems. Immediate action establishing a US carbon trading market with carbon credit pricing and trading supervised by the federal government may be the solution. Costs of achieving high lifetime LFG collection efficiencies are unlikely to be covered with revenues from tipping fee, electricity sales, tax credits, or carbon credit trading. Under scenarios of highly regulated LFG emissions, sustainable landfilling will require research, development, and application of technologies to reduce the marginal abatement cost, including: (1) Diverting rapidly decomposable waste to alternative treatment methods, (2) Reducing fugitive emissions through usage daily/intermediate covers with high oxidation potential, (3) Increasing the lifetime LFG collection efficiency, and (4) Increasing LFG energy value - for instance by producing high-methane gas through biologically altering the LFG generation pathway.
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Date Issued: 2011
Identifier: CFE0003960, ucf:48682
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003960

Title: Human Spaceflight Decision-Making as a Potential Well Problem.
Creator: Litwin, Ari, Handberg, Roger, Dolan, Thomas, Houghton, David, Sadri, Houman, University of Central Florida
Abstract / Description: This study investigates funding within the US human spaceflight program in the time-period from 2004 to 2012. The approach taken employed the (")potential well(") model from physical science. The potential well model constrains any physical body trapped within it, and similarly a political (")funding well(") will constrain all programmatic decision-making.Two potential well models are employed, one represents classical physics while the other represents quantum physics. Since each model...
Show moreThis study investigates funding within the US human spaceflight program in the time-period from 2004 to 2012. The approach taken employed the (")potential well(") model from physical science. The potential well model constrains any physical body trapped within it, and similarly a political (")funding well(") will constrain all programmatic decision-making.Two potential well models are employed, one represents classical physics while the other represents quantum physics. Since each model results in motion with certain properties, it can be seen if funding decisions also exhibit similar properties. In physics, the bifurcation between the classical world of aggregate bodies and the quantum world of individual particles is an indicator of deeper physical principles. This study seeks to explore whether this bifurcation exists in the political world as well. If so, it would help explain space policy evolution from 2004 to 2012, and provide evidence concerning the usefulness of physical models for discovering further trends in social science, including political science.The study of a bifurcation in space policy political decision-making resulted in an unclear relationship since some properties were found to be similar to their physical counterpart, some were found to be different, and one property, the quantization of funding into discrete increments, was absent from political decision-making. Further studies are required to explore this bifurcation in greater detail. However, the potential well did prove to be a powerful model in explaining the evolution of human spaceflight policy in 2004 to 2012 as it provided a framework to explain dynamics that may have otherwise remained unclear.
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Date Issued: 2012
Identifier: CFE0004401, ucf:49370
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004401

Title: Recidivism Measurement and Sanction Effectiveness in Youth Diversion Programs.
Creator: Maroney, Thomas, Wan, Thomas, Sanborn, Joseph, Wolf, Ross, Zhang, Ning, University of Central Florida
Abstract / Description: With the rapid growth of juvenile offender diversion programs, which use many non-traditional sanctions, the effectiveness of sanction combinations in juvenile diversion programs and in each individual program needs to be evaluated. Those making sanctioning decisions currently do so based on intuition rather than using an evidence- or theory-based approach. Considerable research has examined the relationship between offender risk factors and recidivism (who is more likely to reoffend?) and...
Show moreWith the rapid growth of juvenile offender diversion programs, which use many non-traditional sanctions, the effectiveness of sanction combinations in juvenile diversion programs and in each individual program needs to be evaluated. Those making sanctioning decisions currently do so based on intuition rather than using an evidence- or theory-based approach. Considerable research has examined the relationship between offender risk factors and recidivism (who is more likely to reoffend?) and between offender risk factors and sanctions (who is more likely to receive what sanctions?), but little is known about the relationship between sanctions and recidivism (which sanctions best reduce recidivism and for whom?). Furthermore, recidivism studies vary drastically in how they measure or quantify recidivism. This variability of approach makes comparing studies difficult and provides a less-than-complete picture of recidivism in general. The present study used data from one specific youth diversion program to test certain hypotheses of sanctioning by developing and testing a model for assigning sanction combinations to certain offenders on the basis of their individual characteristics. The study first developed measurement models for Offender Risk Propensity, Multiplicity of Sanctions, and Recidivism using structural equation modeling (SEM). Then predictive models were developed to test specific relationships. Understanding the effectiveness of certain sanction packages on certain offenders can form the basis for effective sanctioning in youth diversion programs. This study sought to answer three research questions: What is the best way to measure recidivism? Does completion of a restorative justice program reduce recidivism? Which sanctions, if any, reduce recidivism for specific offender types? To answer the first question: a multi-indicator latent construct of recidivism did a very good job of measuring variation in recidivism. Multiple indicators analyzed simultaneously produced a robust tool that can be used in other recidivism studies and help to reduce comparability issues between studies. The recidivism construct, when tested as a function of completion of the restorative justice program, was seen to produce a significant model having an overall good fit with the data. Thus to answer the second research question: offenders' completion status for the restorative justice program was shown to be a significant predictor of the latent construct of recidivism at the 0.05 level (two-tailed), with those who failed to complete (or chose not to participate) having higher recidivism than did those who completed the program. To answer the third research question: the assignment of specific sanctions (both those suggested by research and theory and those traditionally assigned by this and similar programs) on the entire data set (and on various subsets) of this study have no statistically significant impact on recidivism at the 0.05 level (two tailed).The findings suggest many policy implications. Consistency is all but nonexistent in recidivism measurements in the academic literature and in program review studies. A multi-indicator latent construct of recidivism, such as the one proposed and proven effective in this study, provides a more complete picture than simply conceptualizing recidivism by one dummy variable. This recidivism model can be used as the endogenous variable to evaluate programs and their practices and could reduce the problem of study comparability. This could lead to a better understanding of program characteristics and their impact on offender success. This study also found that completion of the Neighborhood Restorative Justice Program was a significant predictor of recidivism, yet none of the eleven most commonly assigned sanctions were seen to have a significant impact on recidivism for any subgroup. Proponents of restorative justice argue that it is the programs' characteristics and not their specific activities that make the programs successful. Reintegrative Shaming Theory and Labeling Theory support this claim and suggest the best approach to address youth criminal behavior is to admonish the act and not the actor, have the offender and community agree on a plan to make the community whole after that criminal act, and prevent repeated interaction with the formal criminal justice system which encourages the youth to see themself as a deviant and engage in further deviant behavior. These characteristics should be further examined and widely employed if confirmed.
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Date Issued: 2012
Identifier: CFE0004406, ucf:49392
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004406

Title: Facilitating Adaptive Team Performance: The Influence of Membership Fluidity on Learning.
Creator: Bedwell, Wendy, Salas, Eduardo, Jentsch, Kimberly, Jentsch, Florian, Rico Munoz, Ramon, Fiore, Stephen, University of Central Florida
Abstract / Description: Organizations across work domains that utilize teams to achieve organizational outcomes experience change. Resources change. Project deadlines change. Personnel change. Within the scientific community, research has recently surged on the topic of team adaptation to address the issue of change specifically within teams. There have generally been two lines of research regarding team adaptation (task and membership). This effort is focused on membership. Teams are not static(-)members come and...
Show moreOrganizations across work domains that utilize teams to achieve organizational outcomes experience change. Resources change. Project deadlines change. Personnel change. Within the scientific community, research has recently surged on the topic of team adaptation to address the issue of change specifically within teams. There have generally been two lines of research regarding team adaptation (task and membership). This effort is focused on membership. Teams are not static(-)members come and go. The membership adaptation literature has traditionally focused on the performance effects of newcomers to teams. Yet in practice, more and more teams today experience membership loss without replacement. Military units are stretched to capacity. Economic conditions have forced organizations to do more with less. When members leave, they are rarely, if ever, replaced. The very nature of some organizations lends itself to fluid team memberships. Consider an emergency room where a team of nurses and doctors work on Patient A. When a more critical Patient B arrives that requires the expertise of one of those team members, that doctor will leave the Patient A to tend to the Patient B. This practice is common in such work environments. Yet despite the prevalence of this practice, the scientific community knows very little about the impact of losing members on team performance. The current study examines the impact of membership fluidity on team performance. The purpose of this study was twofold. First, there was the need to address an empirical gap in the adaptation literature by focusing on membership changes (loss and loss with replacement) in non-creative tasks. Second was the consideration of the processes underlying adaptation(-)namely learning, operationalized as the development of effective shared mental models (SMMs). Thus, a primary goal was to determine the magnitude of team performance decrements associated with such changes within a decision-making task as well as the associated changes in team process. Results suggest that three-person intact teams demonstrated greater adaptive performance than membership loss with replacement teams. Furthermore, two-person intact teams developed more similar task and team interaction SMMs than membership loss teams when SMMs were indexed as a Euclidean distance score. There were no differences in the level of sharedness regarding task, team interaction or teammate SMMs for three-person intact teams as compared to membership loss with replacement teams. However, when teammate SMMs were operationalized as the personality facets (i.e., the Big 5) in exploratory analyses, three-person intact teams did develop more similar SMMs regarding the agreeableness facet than membership loss with replacement teams. Additionally, when operationalized as Euclidean distance, the agreeableness facet significantly predicted adaptive team performance(-)specifically, the smaller the distance (i.e., more similar the MMs), the greater the adaptive performance in teams. When operationalized as the similarity index, the neuroticism facet significantly predicted adaptive team performance such that the more similar the SMMs, the greater the adaptive performance in teams. Results suggest that membership fluidity does negatively influence the development of shared mental models among teammates. Furthermore, this study provides additional evidence that teammate and team interaction mental models, which are typically not examined together in team studies, are differentially influenced by membership fluidity and differentially predict outcomes like adaptive team performance. This suggests researchers should include both of these cognitive components of team performance to fully understand the nature of these constructs.
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Date Issued: 2012
Identifier: CFE0004356, ucf:49448
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004356

Title: Automatic Scenario Generation using Procedural Modeling Techniques.
Creator: Martin, Glenn, Hughes, Charles, Moshell, Jack, Fiore, Stephen, Orooji, Ali, University of Central Florida
Abstract / Description: Training typically begins with a pre-existing scenario. The training exercise is performed and then an after action review is sometimes held. This (")training pipeline(") is repeated for each scenario that will be used that day. This approach is used routinely and often effectively, yet it has a number of aspects that can result in poor training. In particular, this process commonly has two associated events that are undesirable. First, scenarios are re-used over and over, which can reduce...
Show moreTraining typically begins with a pre-existing scenario. The training exercise is performed and then an after action review is sometimes held. This (")training pipeline(") is repeated for each scenario that will be used that day. This approach is used routinely and often effectively, yet it has a number of aspects that can result in poor training. In particular, this process commonly has two associated events that are undesirable. First, scenarios are re-used over and over, which can reduce their effectiveness in training. Second, additional responsibility is placed on the individual training facilitator in that the trainer must now track performance improvements between scenarios. Taking both together can result in a multiplicative degradation in effectiveness. Within any simulation training exercise, a scenario definition is the starting point. While these are, unfortunately, re-used and over-used, they can, in fact, be generated from scratch each time. Typically, scenarios include the entire configuration for the simulators such as entities used, time of day, weather effects, entity starting locations and, where applicable, munitions effects. In addition, a background story (exercise briefing) is given to the trainees. The leader often then develops a mission plan that is shared with the trainee group. Given all of these issues, scientists began to explore more purposeful, targeted training. Rather than an ad-hoc creation of a simulation experience, there was an increased focus on the content of the experience and its effects on training. Previous work in scenario generation, interactive storytelling and computational approaches, while providing a good foundation, fall short on addressing the need for adaptive, automatic scenario generation. This dissertation addresses this need by building up a conceptual model to represent scenarios, mapping that conceptual model to a computational model, and then applying a newer procedural modeling technique, known as Functional L-systems, to create scenarios given a training objective, scenario complexity level desired, and sets of baseline and vignette scenario facets.A software package, known as PYTHAGORAS, was built and is presented that incorporates all these contributions into an actual tool for creating scenarios (both manual and automatic approaches are included). This package is then evaluated by subject matter experts in a scenario-based (")Turing Test(") of sorts where both system-generated scenarios and human-generated scenarios are evaluated by independent reviewers. The results are presented from various angles.Finally, a review of how such a tool can affect the training pipeline is included. In addition, a number of areas into which scenario generation can be expanded are reviewed. These focus on additional elements of both the training environment (e.g., buildings, interiors, etc.) and the training process (e.g., scenario write-ups, etc.).
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Date Issued: 2012
Identifier: CFE0004265, ucf:49525
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004265

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