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Title: Applications of Deep Learning Models for Traffic Prediction Problems.
Creator: Rahman, Rezaur, Hasan, Samiul, Abdel-Aty, Mohamed, Zaki Hussein, Mohamed, University of Central Florida
Abstract / Description: Deep learning coupled with existing sensors based multiresolution traffic data and future connected technologies has immense potential to improve traffic operation and management. But to deal with complex transportation problems, we need efficient modeling frameworks for deep learning models. In this study, we propose two different modeling frameworks using Deep Long Short-Term Memory Neural Network (LSTM NN) model to predict future traffic state (speed and signal queue length). In our first...
Show moreDeep learning coupled with existing sensors based multiresolution traffic data and future connected technologies has immense potential to improve traffic operation and management. But to deal with complex transportation problems, we need efficient modeling frameworks for deep learning models. In this study, we propose two different modeling frameworks using Deep Long Short-Term Memory Neural Network (LSTM NN) model to predict future traffic state (speed and signal queue length). In our first problem, we present a modeling framework using deep LSTM NN model to predict traffic speeds in freeways during regular traffic condition as well as under extreme traffic demand, such as a hurricane evacuation. The approach is tested using real-world traffic data collected during hurricane Irma's evacuation for the interstate 75 (I-75), a major evacuation route in Florida. We perform several experiments for predicting speeds for 5 min, 10 min, and 15 min ahead of current time. The results are compared against other traditional prediction models such as K-Nearest Neighbor, Analytic Neural Network (ANN), Auto-Regressive Integrated Moving Average (ARIMA). We find that LSTM-NN performs better than these parametric and non-parametric models. Apart from the improvement in traffic operation, the proposed method can be integrated with evacuation traffic management systems for a better evacuation operation. In our second problem, we develop a data-driven real-time queue length prediction technique using deep LSTM NN model. We consider a connected corridor where information from vehicle detectors (located at the intersection) will be shared to consecutive intersections. We assume that the queue length of an intersection in the next cycle will depend on the queue length of the target and two upstream intersections in the current cycle. We use InSync Adaptive Traffic Control System (ATCS) data to train a Long Short-Term Memory Neural Network model capturing time-dependent patterns of a queue of a signal. To select the best combination of hyperparameters, we use sequential model-based optimization (SMBO) technique. Our experiment results show that the proposed modeling framework performs very well to predict the queue length. Although we run our experiments predicting the queue length for a single movement, the proposed method can be applied for other movements as well. Queue length prediction is a crucial part of an ATCS to optimize control parameters and this method can improve the existing signal optimization technique for ATCS.
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Date Issued: 2019
Identifier: CFE0007516, ucf:52654
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007516

Title: Real-time SIL Emulation Architecture for Cooperative Automated Vehicles.
Creator: Gupta, Nitish, Pourmohammadi Fallah, Yaser, Rahnavard, Nazanin, Vosoughi, Azadeh, University of Central Florida
Abstract / Description: This thesis presents a robust, flexible and real-time architecture for Software-in-the-Loop (SIL) testing of connected vehicle safety applications. Emerging connected and automated vehicles (CAV) use sensing, communication and computing technologies in the design of a host of new safety applications. Testing and verification of these applications is a major concern for the automotive industry. The CAV safety applications work by sharing their state and movement information over wireless...
Show moreThis thesis presents a robust, flexible and real-time architecture for Software-in-the-Loop (SIL) testing of connected vehicle safety applications. Emerging connected and automated vehicles (CAV) use sensing, communication and computing technologies in the design of a host of new safety applications. Testing and verification of these applications is a major concern for the automotive industry. The CAV safety applications work by sharing their state and movement information over wireless communication links. Vehicular communication has fueled the development of various Cooperative Vehicle Safety (CVS) applications. Development of safety applications for CAV requires testing in many different scenarios. However, the recreation of test scenarios for evaluating safety applications is a very challenging task. This is mainly due to the randomness in communication, difficulty in recreating vehicle movements precisely, and safety concerns for certain scenarios. We propose to develop a standalone Remote Vehicle Emulator (RVE) that can reproduce V2V messages of remote vehicles from simulations or from previous tests, while also emulating the over the air behavior of multiple communicating nodes. This is expected to significantly accelerate the development cycle. RVE is a unique and easily configurable emulation cum simulation setup to allow Software in the Loop (SIL) testing of connected vehicle applications in a realistic and safe manner. It will help in tailoring numerous test scenarios, expediting algorithm development and validation as well as increase the probability of finding failure modes. This, in turn, will help improve the quality of safety applications while saving testing time and reducing cost.The RVE architecture consists of two modules, the Mobility Generator, and the Communication emulator. Both of these modules consist of a sequence of events that are handled based on the type of testing to be carried out. The communication emulator simulates the behavior of MAC layer while also considering the channel model to increase the probability of successful transmission. It then produces over the air messages that resemble the output of multiple nodes transmitting, including corrupted messages due to collisions. The algorithm that goes inside the emulator has been optimized so as to minimize the communication latency and make this a realistic and real-time safety testing tool. Finally, we provide a multi-metric experimental evaluation wherein we verified the simulation results with an identically configured ns3 simulator. With the aim to improve the quality of testing of CVS applications, this unique architecture would serve as a fundamental design for the future of CVS application testing.
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Date Issued: 2018
Identifier: CFE0007185, ucf:52280
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007185

Title: The Performance and Power Impact of Using Multiple DRAM Address Mapping Schemes in Multicore Processors.
Creator: Jadaa, Rami, Heinrich, Mark, DeMara, Ronald, Yuan, Jiann-Shiun, University of Central Florida
Abstract / Description: Lowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic...
Show moreLowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic mapping scheme over the fixed one. Results show that applications' performance varies according to the mapping scheme used, and a dynamic mapping scheme achieves up to 2x increase in peak bandwidth utilization and around 30% higher energy efficiency than a system using only a single fixed scheme Moreover, the technique can be used to limit memory accesses into a subset of the memory devices by controlling data allocation at a finer granularity, providing a method to throttle main memory by allowing un-accessed devices to be put into power-down mode, hence saving power to meet a certain power budget.
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Date Issued: 2011
Identifier: CFE0004121, ucf:49118
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004121

Title: Design, Characterization and Analysis of Electrostatic Discharge (ESD) Protection Solutions in Emerging and Modern Technologies.
Creator: Liu, Wen, Liou, Juin, Yuan, Jiann-Shiun, Sundaram, Kalpathy, Shen, Zheng, Chen, Quanfang, University of Central Florida
Abstract / Description: Electrostatic Discharge (ESD) is a significant hazard to electronic components and systems. Based on a specific processing technology, a given circuit application requires a customized ESD consideration that includes the devices' operating voltage, leakage current, breakdown constraints, and footprint. As new technology nodes mature every 3-5 years, design of effective ESD protection solutions has become more and more challenging due to the narrowed design window, elevated electric field and...
Show moreElectrostatic Discharge (ESD) is a significant hazard to electronic components and systems. Based on a specific processing technology, a given circuit application requires a customized ESD consideration that includes the devices' operating voltage, leakage current, breakdown constraints, and footprint. As new technology nodes mature every 3-5 years, design of effective ESD protection solutions has become more and more challenging due to the narrowed design window, elevated electric field and current density, as well as new failure mechanisms that are not well understood. The endeavor of this research is to develop novel, effective and robust ESD protection solutions for both emerging technologies and modern complementary metal(-)oxide(-)semiconductor (CMOS) technologies.The Si nanowire field-effect transistors are projected by the International Technology Roadmap for Semiconductors as promising next-generation CMOS devices due to their superior DC and RF performances, as well as ease of fabrication in existing Silicon processing. Aiming at proposing ESD protection solutions for nanowire based circuits, the dimension parameters, fabrication process, and layout dependency of such devices under Human Body Mode (HBM) ESD stresses are studied experimentally in company with failure analysis revealing the failure mechanism induced by ESD. The findings, including design methodologies, failure mechanism, and technology comparisons should provide practical knowhow of the development of ESD protection schemes for the nanowire based integrated circuits. Organic thin-film transistors (OTFTs) are the basic elements for the emerging flexible, printable, large-area, and low-cost organic electronic circuits. Although there are plentiful studies focusing on the DC stress induced reliability degradation, the operation mechanism of OTFTs subject to ESD is not yet available in the literature and are urgently needed before the organic technology can be pushed into consumer market. In this work, the ESD operation mechanism of OTFT depending on gate biasing condition and dimension parameters are investigated by extensive characterization and thorough evaluation. The device degradation evolution and failure mechanism under ESD are also investigated by specially designed experiments. In addition to the exploration of ESD protection solutions in emerging technologies, efforts have also been placed in the design and analysis of a major ESD protection device, diode-triggered-silicon-controlled-rectifier (DTSCR), in modern CMOS technology (90nm bulk). On the one hand, a new type DTSCR having bi-directional conduction capability, optimized design window, high HBM robustness and low parasitic capacitance are developed utilizing the combination of a bi-directional silicon-controlled-rectifier and bi-directional diode strings. On the other hand, the HBM and Charged Device Mode (CDM) ESD robustness of DTSCRs using four typical layout topologies are compared and analyzed in terms of trigger voltage, holding voltage, failure current density, turn-on time, and overshoot voltage. The advantages and drawbacks of each layout are summarized and those offering the best overall performance are suggested at the end.
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Date Issued: 2012
Identifier: CFE0004571, ucf:49199
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004571

Title: THE EFFECTS OF PHOSPHATE AND SILICATE INHIBITORS ON SURFACE ROUGHNESS AND COPPER RELEASE IN WATER DISTRIBUTION SYSTEMS.
Creator: MacNevin, David, Taylor, James, University of Central Florida
Abstract / Description: The effects of corrosion inhibitors on water quality and the distribution system were studied. This dissertation investigates the effect of inhibitors on iron surface roughness, copper surface roughness, and copper release. Corrosion inhibitors included blended poly/ortho phosphate, sodium orthophosphate, zinc orthophosphate, and sodium silicate. These inhibitors were added to a blend of surface water, groundwater, and desalinated brackish water. Surface roughness of galvanized iron, unlined...
Show moreThe effects of corrosion inhibitors on water quality and the distribution system were studied. This dissertation investigates the effect of inhibitors on iron surface roughness, copper surface roughness, and copper release. Corrosion inhibitors included blended poly/ortho phosphate, sodium orthophosphate, zinc orthophosphate, and sodium silicate. These inhibitors were added to a blend of surface water, groundwater, and desalinated brackish water. Surface roughness of galvanized iron, unlined cast iron, lined cast iron, and polyvinyl chloride was measured using pipe coupons exposed for three months. Roughness of each pipe coupon was measured with an optical surface profiler before and after exposure to inhibitors. For most materials, inhibitor did not have a significant effect on surface roughness; instead, the most significant factor determining the final surface roughness was the initial surface roughness. Coupons with low initial surface roughness tended to have an increase in surface roughness during exposure, and vice versa, implying that surface roughness tended to regress towards an average or equilibrium value. For unlined cast iron, increased alkalinity and increased temperature tended to correspond with increases in surface roughness. Unlined cast iron coupons receiving phosphate inhibitors were more likely to have a significant change in surface roughness, suggesting that phosphate inhibitors affect stability of iron pipe scales. Similar roughness data collected with new copper coupons showed that elevated orthophosphate, alkalinity, and temperature were all factors associated with increased copper surface roughness. The greatest increases in surface roughness were observed with copper coupons receiving phosphate inhibitors. Smaller increases were observed with copper coupons receiving silicate inhibitor or no inhibitor. With phosphate inhibitors, elevated temperature and alkalinity were associated with larger increases in surface roughness and blue-green copper (II) scales.. Otherwise a compact, dull red copper (I) scale was observed. These data suggest that phosphate inhibitor addition corresponds with changes in surface morphology, and surface composition, including the oxidation state of copper solids. The effects of corrosion inhibitors on copper surface chemistry and cuprosolvency were investigated. Most copper scales had X-ray photoelectron spectroscopy binding energies consistent with a mixture of Cu2O, CuO, Cu(OH)2, and other copper (II) salts. Orthophosphate and silica were detected on copper surfaces exposed to each inhibitor. All phosphate and silicate inhibitors reduced copper release relative to the no inhibitor treatments, keeping total copper below the 1.3 mg/L MCLG for all water quality blends. All three kinds of phosphate inhibitors, when added at 1 mg/L as P, corresponded with a 60% reduction in copper release relative to the no inhibitor control. On average, this percent reduction was consistent across varying water quality conditions in all four phases. Similarly when silicate inhibitor was added at 6 mg/L as SiO2, this corresponded with a 25-40% reduction in copper release relative to the no inhibitor control. Hence, on average, for the given inhibitors and doses, phosphate inhibitors provided more predictable control of copper release across changing water quality conditions. A plot of cupric ion concentration versus orthophosphate concentration showed a decrease in copper release consistent with mechanistic control by either cupric phosphate solubility or a diffusion limiting phosphate film. Thermodynamic models were developed to identify feasible controlling solids. For the no inhibitor treatment, Cu(OH)2 provided the closest prediction of copper release. With phosphate inhibitors both Cu(OH)2 and Cu(PO4)·2H2O models provided plausible predictions. Similarly, with silicate inhibitor, the Cu(OH)2 and CuSiO3·H2O models provided plausible predictions.
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Date Issued: 2008
Identifier: CFE0002001, ucf:47621
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002001

Title: CONTROL STRATEGY FOR MAXIMIZING POWER CONVERSION EFFICIENCY AND EFFECTIVENESS OF THREE PORT SOLAR CHARGING STATION FOR ELECTRIC VEHICLES.
Creator: Hamilton, Christopher, Batarseh, Issa, University of Central Florida
Abstract / Description: Recent trends in the energy sector have provided opportunities in the research of alternative energy sources and optimization of systems that harness these energy sources. With the rising cost of fossil fuel and rising concern about detrimental effects that fossil fuel consumption has on the environment, electric vehicles are becoming more prevalent. A study put out in 2009 gives a prediction that in the year 2025, 20% of new vehicles will be PHEVs. As energy providers become more concerned...
Show moreRecent trends in the energy sector have provided opportunities in the research of alternative energy sources and optimization of systems that harness these energy sources. With the rising cost of fossil fuel and rising concern about detrimental effects that fossil fuel consumption has on the environment, electric vehicles are becoming more prevalent. A study put out in 2009 gives a prediction that in the year 2025, 20% of new vehicles will be PHEVs. As energy providers become more concerned about a growing population and diminishing energy source, they are looking into alternative energy sources such as wind and solar power. Much of this is done on a large scale with vast amounts of land used for solar or wind farms to provide energy to the grid. However, as population grows, requirements of the physical components of a power transmission system will become more demanding and the need for remote micro-grids will become more prevalent. Micro-grids are essentially smaller subsystems of a distribution system that provide power to a confined group of loads, or households. Using the idea of micro grid technology, a solar charging station can be used as a source to provide energy for the immediate surroundings, or also to electric vehicles that are demanding energy from the panels. Solar charging stations are becoming very popular, however the need for improvement and optimization of these systems is needed. This thesis will present a method for redesigning the overall architecture of the controls and power electronics of typical carports so that efficiency, reliability and modularity are achieved. Specifically, a typical carport, as seen commonly today, has been built on the University of Central Florida campus in Orlando. This carport was designed in such a way that shifting from conventional charging methods is made easy while preserving the fundamental requirements of a practical solar carport.
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Date Issued: 2010
Identifier: CFE0003490, ucf:48954
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003490

Title: A NEW FRAMEWORK FOR QOS PROVISIONING IN WIRELESS LANS USING THE P-PERSISTENT MAC PROTOCOL.
Creator: Anna, Kiran Babu, Bassiouni, Mostafa, University of Central Florida
Abstract / Description: The support of multimedia traffic over IEEE 802.11 wireless local area networks (WLANs) has recently received considerable attention. This dissertation has proposed a new framework that provides efficient channel access, service differentiation and statistical QoS guarantees in the enhanced distributed channel access (EDCA) protocol of IEEE 802.11e. In the first part of the dissertation, the new framework to provide QoS support in IEEE 802.11e is presented. The framework uses three...
Show moreThe support of multimedia traffic over IEEE 802.11 wireless local area networks (WLANs) has recently received considerable attention. This dissertation has proposed a new framework that provides efficient channel access, service differentiation and statistical QoS guarantees in the enhanced distributed channel access (EDCA) protocol of IEEE 802.11e. In the first part of the dissertation, the new framework to provide QoS support in IEEE 802.11e is presented. The framework uses three independent components, namely, a core MAC layer, a scheduler, and an admission control. The core MAC layer concentrates on the channel access mechanism to improve the overall system efficiency. The scheduler provides service differentiation according to the weights assigned to each Access Category (AC). The admission control provides statistical QoS guarantees. The core MAC layer developed in this dissertation employs a P-Persistent based MAC protocol. A weight-based fair scheduler to obtain throughput service differentiation at each node has been used. In wireless LANs (WLANs), the MAC protocol is the main element that determines the efficiency of sharing the limited communication bandwidth of the wireless channel. In the second part of the dissertation, analytical Markov chain models for the P-Persistent 802.11 MAC protocol under unsaturated load conditions with heterogeneous loads are developed. The Markov models provide closed-form formulas for calculating the packet service time, the packet end-to-end delay, and the channel capacity in the unsaturated load conditions. The accuracy of the models has been validated by extensive NS2 simulation tests and the models are shown to give accurate results. In the final part of the dissertation, the admission control mechanism is developed and evaluated. The analytical model for P-Persistent 802.11 is used to develop a measurement-assisted model-based admission control. The proposed admission control mechanism uses delay as an admission criterion. Both distributed and centralized admission control schemes are developed and the performance results show that both schemes perform very efficiently in providing the QoS guarantees. Since the distributed admission scheme control does not have a complete state information of the WLAN, its performance is generally inferior to the centralized admission control scheme. The detailed performance results using the NS2 simulator have demonstrated the effectiveness of the proposed framework. Compared to 802.11e EDCA, the scheduler consistently achieved the desired throughput differentiation and easy tuning. The core MAC layer achieved better delays in terms of channel access, average packet service time and end-to-end delay. It also achieved higher system throughput than EDCA for any given service differentiation ratio. The admission control provided the desired statistical QoS guarantees.
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Date Issued: 2010
Identifier: CFE0003243, ucf:48513
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003243

Title: CURRICULUM CONTROL AND TEACHERS' PERCEPTIONS OF PROFESSIONAL DISCRETION AND SATISFACTION.
Creator: May, Donald, Pawlas, George, University of Central Florida
Abstract / Description: The goal of this research was to investigate teachers' perceptions of professional discretion and satisfaction related to internal and external factors of curriculum control. Results of the study were intended to provide data to policy makers and school district administrators that could be used in the development and implementation of the curriculum reform process. Middle and high school teachers in a large central Florida school district completed the survey. The survey's six...
Show moreThe goal of this research was to investigate teachers' perceptions of professional discretion and satisfaction related to internal and external factors of curriculum control. Results of the study were intended to provide data to policy makers and school district administrators that could be used in the development and implementation of the curriculum reform process. Middle and high school teachers in a large central Florida school district completed the survey. The survey's six constructs were 1. Influence of Teacher Beliefs 2. Perceptions of Success and Satisfaction 3. Influence of Tests and Curriculum Guides 4. Teacher Control of Pedagogy 5. Leadership 6. Maintaining High Standards The research questions focused on determining the difference in perspectives due to years of teaching experience, level of teaching (middle or high school), and curriculum control category (high, medium, or low). The results revealed there was not significant disagreement among teacher perceptions based on years of teaching experience. However, results indicated significant differences in perceptions based on level of teaching and curriculum control category in regard to the six survey constructs. The construct of leadership revealed significant differences between both levels of teaching and curriculum control categories. Overall, the results indicated a significant relationship among curriculum control policies and effects on teachers' perceptions of professional discretion and satisfaction. The literature on curriculum reform efforts since the 1980s, specifically in the areas of curriculum standards, textbook adoption policies, testing policies and leadership practices, framed the study. The literature review focused on existing research issues within the six constructs and the research questions. The information gained from this study may be used to inform policies, improve teachers' working conditions, and promote teacher and leadership effectiveness. Recommendations for practice were addressed in terms of what policy makers, school district administrators, and individual classroom teachers can and should do to implement and support meaningful curriculum reform. The researcher emphasized that recognizing the professional expertise and knowing the perspective of teachers are key to the development and implementation of an effective curriculum reform process.
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Date Issued: 2010
Identifier: CFE0003210, ucf:48572
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003210

Title: Field Evaluation of Insync Adaptive Traffic Signal Control System in Multiple Environments Using Multiple Approaches.
Creator: Shafik, Md Shafikul Islam, Radwan, Essam, Abou-Senna, Hatem, Eluru, Naveen, University of Central Florida
Abstract / Description: Since the beginning of signalization of intersections, the management of traffic congestion is one of most critical challenges specifically for the city and urbanized area. Almost all the municipal agencies struggle to manage the perplexities associated with traffic congestion or signal control. The Adaptive Traffic Control System (ATCS), an advanced and major technological component of the Intelligent Transportation Systems (ITS) is considered the most dynamic and real-time traffic...
Show moreSince the beginning of signalization of intersections, the management of traffic congestion is one of most critical challenges specifically for the city and urbanized area. Almost all the municipal agencies struggle to manage the perplexities associated with traffic congestion or signal control. The Adaptive Traffic Control System (ATCS), an advanced and major technological component of the Intelligent Transportation Systems (ITS) is considered the most dynamic and real-time traffic management technology and has potential to effectively manage rapidly varying traffic flow relative to the current state-of-the-art traffic management practices.InSync ATCS is deployed in multiple states throughout the US and expanding on a large scale. Although there had been several 'Measure of Effectiveness' studies performed previously, the performance of InSync is not unquestionable especially because the previous studies failed to subject for multiple environments, approaches, and variables. Most studies are accomplished through a single approach using simple/na(&)#239;ve before-after method without any control group/parameter. They also lacked ample statistical analysis, historical, maturation and regression artifacts. An attempt to evaluate the InSync ATCS in varying conditions through multiple approaches was undertaken for the SR-434 and Lake Underhill corridor in Orange County, Florida. A before-after study with an adjacent corridor as control group and volume as a control parameter has been performed where data of multiple variables were collected by three distinct procedures. The average/floating-car method was utilized as a rudimentary data collection process and 'BlueMac' and 'InSync' system database was considered as secondary data sources. Data collected for three times a day for weekdays and weekends before and after the InSync ATCS was deployed.Results show variation in both performance and scale. It proved ineffective in some of the cases, especially for the left turns, total intersection queue/delay and when the intersection volumes approach capacity. The results are verified through appropriate statistical analysis.
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Date Issued: 2017
Identifier: CFE0006915, ucf:51687
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006915

Title: On Obama Administration Gun Policy With Continual Reference To The Multiple Streams Model.
Creator: Hristakopoulos, Michael, Vieux, Andrea, Wilson, Bruce, Kinsey, Barbara, University of Central Florida
Abstract / Description: The Multiple Streams model developed by John Kingdon (1995) and Nikolaos Zahariadis (2007) provides a valuable framework for understanding the nature of policy change. This investigation draws extensively upon the Multiple Streams framework in order to understand the development of gun-control policy initiatives under President Barack Obama.The investigation uses a case-study approach with in-depth analysis of four different mass-shooting events that took place in the United States between...
Show moreThe Multiple Streams model developed by John Kingdon (1995) and Nikolaos Zahariadis (2007) provides a valuable framework for understanding the nature of policy change. This investigation draws extensively upon the Multiple Streams framework in order to understand the development of gun-control policy initiatives under President Barack Obama.The investigation uses a case-study approach with in-depth analysis of four different mass-shooting events that took place in the United States between 2009 and 2012. Reconstruction of the shooting events and detailed parsing of the Obama administration's official responses to each incident, when viewed through the Multiple Streams lens, clearly explain why Obama's aggressive policy initiative was so delayed in its emergence in spite of several shootings and the President's clearly stated belief that gun-reform was a necessary step for the federal government. While the term (")policy change(") is broad and may encompass all sorts of governmental responsiveness, the term herein should be interpreted in the narrowest sense: exclusively encompassing legislative initiatives.Ultimately, the investigation concludes that numerous factors, but most prominently concerns about the timing and results of the 2010 Midterm and 2012 General Elections, prevented an aggressive pursuit of gun-reform prior to January 2013. The tragic shooting of 28 people in Newtown, Connecticut, then served as a prime focusing event for the President to aggressively engage a long-standing goal.
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Date Issued: 2013
Identifier: CFE0004865, ucf:49716
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004865

Title: Modeling and Simulation of All-electric Aircraft Power Generation and Actuation.
Creator: Woodburn, David, Wu, Xinzhang, Batarseh, Issa, Georgiopoulos, Michael, Haralambous, Michael, Chow, Louis, University of Central Florida
Abstract / Description: Modern aircraft, military and commercial, rely extensively on hydraulic systems. However, there is great interest in the avionics community to replace hydraulic systems with electric systems. There are physical challenges to replacing hydraulic actuators with electromechanical actuators (EMAs), especially for flight control surface actuation. These include dynamic heat generation and power management.Simulation is seen as a powerful tool in making the transition to all-electric aircraft by...
Show moreModern aircraft, military and commercial, rely extensively on hydraulic systems. However, there is great interest in the avionics community to replace hydraulic systems with electric systems. There are physical challenges to replacing hydraulic actuators with electromechanical actuators (EMAs), especially for flight control surface actuation. These include dynamic heat generation and power management.Simulation is seen as a powerful tool in making the transition to all-electric aircraft by predicting the dynamic heat generated and the power flow in the EMA. Chapter 2 of this dissertation describes the nonlinear, lumped-element, integrated modeling of a permanent magnet (PM) motor used in an EMA. This model is capable of representing transient dynamics of an EMA, mechanically, electrically, and thermally.Inductance is a primary parameter that links the electrical and mechanical domains and, therefore, is of critical importance to the modeling of the whole EMA. In the dynamic mode of operation of an EMA, the inductances are quite nonlinear. Chapter 3 details the careful analysis of the inductances from finite element software and the mathematical modeling of these inductances for use in the overall EMA model.Chapter 4 covers the design and verification of a nonlinear, transient simulation model of a two-step synchronous generator with three-phase rectifiers. Simulation results are shown.
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Date Issued: 2013
Identifier: CFE0005074, ucf:49975
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005074

Title: Structural and Functional Studies of Glycine Riboswitches and Development of Fab Chaperone Assisted RNA Crystallography.
Creator: Sherman, Eileen, Ye, Jingdong, Kolpashchikov, Dmitry, Koculi, Eda, Harper, James, Self, William, University of Central Florida
Abstract / Description: The glycine riboswitch is a structured RNA found upstream of genes in mRNA transcripts in many bacteria, functioning as a biofeedback gene regulator. Upon binding glycine, a complete RNA transcript including gene sequences is transcribed, effectively turning on gene expression. In an effort to understand the intricacies of its functioning, many mutants of the riboswitch were made and characterized during Ph. D. work, resulting in discovery of a P0 duplex/kink-turn motif involving a few...
Show moreThe glycine riboswitch is a structured RNA found upstream of genes in mRNA transcripts in many bacteria, functioning as a biofeedback gene regulator. Upon binding glycine, a complete RNA transcript including gene sequences is transcribed, effectively turning on gene expression. In an effort to understand the intricacies of its functioning, many mutants of the riboswitch were made and characterized during Ph. D. work, resulting in discovery of a P0 duplex/kink-turn motif involving a few nucleotides upstream of the established glycine riboswitch sequence which changed its ligand binding characteristics (Chapter 1). Previously, the two aptamers of the riboswitch were thought to cooperatively bind glycine, but with the inclusion of this leader sequence which forms a kink turn motif with the linker between the two aptamers, glycine binding in one aptamer no longer requires glycine binding in the other. Furthermore, the Kd from three species tested are now a similar, lower value of about 5 (&)#181;M, indicating authenticity of this new consensus sequence. Glycine binding and interaptamer interaction both enhanced one another in trans aptamer assays. Another discovery from this was a shortened construct including all of aptamer II but only part of aptamer I in which a few specific nucleotides prevented glycine binding in aptamer II (Chapter 2). This may provide insight into the nature of interaptamer interactions in the full switch; addition of an oligonucleotide complimentary to these nucleotides restored glycine binding ability to aptamer II. With future development, this could also be a useful molecular biology tool, using two signals, glycine and an oligonucleotide, to allow gene expression.To precisely understand how any macromolecule functions, a 3D structure, obtainable by x-ray crystallography, is vital. A new technique to accomplish that for RNA, precedented in the protein world, is Fab chaperoned crystallography, which has advantages compared to RNA alone. A phage displayed library of Fabs with reduced codon diversity designed for RNA was created, the YSGR Min library (Chapter 3). Its Fabs had specificities and affinities equal to or greater than previous libraries which were originally created for phage displayed selection against proteins. Fab chaperoned RNA crystallography is currently in progress for the glycine riboswitch; the best resolution thus far is 5.3 (&)#197; (Chapter 4). In addition to providing molecular insight into its gene regulation mechanism, a structure of the glycine riboswitch could be applied for use in structure based drug design of novel antibiotics targeting the riboswitch to disrupt important downstream carbon cycle genes in pathogenic bacteria.
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Date Issued: 2014
Identifier: CFE0005549, ucf:50285
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005549

Title: THE FORGOTTEN THIRD BRANCH: THE SUPREME COURT, PUBLIC OPINION, AND THE MEDIA.
Creator: Pitchman, Adrien, Schmidt, Cynthia, University of Central Florida
Abstract / Description: The three branches of government rely on public engagement for the prosperity of the nation. Moreover, informed public opinion is a fundamental tenant of democracy. With that in mind, this paper aims to explore the relationship between the Judicial Branch and the public. Specifically, this paper examines and questions the Supreme Court's efficacy communicating with the public. American constituents are inundated on a daily basis by the clamor of D.C. politics. The twenty four hour news cycle...
Show moreThe three branches of government rely on public engagement for the prosperity of the nation. Moreover, informed public opinion is a fundamental tenant of democracy. With that in mind, this paper aims to explore the relationship between the Judicial Branch and the public. Specifically, this paper examines and questions the Supreme Court's efficacy communicating with the public. American constituents are inundated on a daily basis by the clamor of D.C. politics. The twenty four hour news cycle has given way to politicized headlines and exaggerated pundit commentary on contentious national issues. In a technological age where information is instant and the public has become accustomed to soundbites for education, the Supreme Court is left out of place. Both the Executive Branch and Legislative Branch converse directly with the public when necessary. Politicians frequently address their constituents or discuss complicated issues with voters first hand. However, the Supreme Court has rejected this strategy and instead relies almost exclusively on the press to relay their decisions. The judicial branch is the only third of our government without constant communication to the American people. As a result, the judiciary is relatively ignored by its citizens. By discussing a number of landmark cases since the turn of the century, this paper aims to analyze how those decisions were both announced to the public by the media and how the public received them. The Court has certainly adopted the press as an agent of communication. But is the media truly the proper outlet for the Court's rulings?
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Date Issued: 2015
Identifier: CFH0004771, ucf:45392
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004771

Title: SUPPORT SYSTEMS IN ADOLESCENTS WITH TYPE 1 DIABETES MELLITUS AND THE RELATIONSHIP TO DIABETES-RELATED STRESS, CONFLICT, AND METABOLIC CONTROL.
Creator: Foarde, Samuel, LaManna, Jacqueline, University of Central Florida
Abstract / Description: The purpose of this integrated review of the literature was to explore the effects of social support on diabetes-related stress, conflict, and metabolic control in adolescents with type 1 diabetes mellitus (T1DM). Social support was examined in four subgroups: adolescents with T1DM, family caregivers, peers, and teachers. Relevant findings in the literature revealed a significant deficiency of research devoted to adolescent males with diabetes as well as fathers as primary and secondary...
Show moreThe purpose of this integrated review of the literature was to explore the effects of social support on diabetes-related stress, conflict, and metabolic control in adolescents with type 1 diabetes mellitus (T1DM). Social support was examined in four subgroups: adolescents with T1DM, family caregivers, peers, and teachers. Relevant findings in the literature revealed a significant deficiency of research devoted to adolescent males with diabetes as well as fathers as primary and secondary caregivers. Studies highlighted the importance of fostering autonomy and positive self-image in adolescents with T1DM and described effective interventions to improve diabetes-related stress, reduce disease-related conflict, and improve metabolic control. Findings suggested that nurses caring for adolescents with T1DM and their families should foster positive, open communication, while identifying barriers to problem solving, coping, stress, and optimal glycemic control. Interventions that educate caregivers and peers on how to better communicate and provide support are critical in fostering positive psychological and physiological outcomes in the adolescent with T1DM. The findings of this study may provide guidance in the way that nurses assess, identify, and counsel adolescents with TIDM regarding their disease management and access to support systems.
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Date Issued: 2013
Identifier: CFH0004324, ucf:45057
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004324

Title: Repro, But Make It Fashion: Discourses on Sex, Sexuality, and Reproduction in Teen Vogue Magazine.
Creator: Londono, Estefany, Carter, Shannon, Armato, Michael, Donley, Amy, Bubriski, Anne, University of Central Florida
Abstract / Description: There are many possible sources for youth to become educated about sexuality and reproduction, however the media are cited as particularly powerful and prominent sources of information (Jaworski, 2009). Particularly in an era in which abstinence-only messaging dominates sex education, media become a source to which young people turn and where they receive much of their sex-based messaging. Due to backlash over problematic content that perpetuates gender stereotypes and relays harmful messages...
Show moreThere are many possible sources for youth to become educated about sexuality and reproduction, however the media are cited as particularly powerful and prominent sources of information (Jaworski, 2009). Particularly in an era in which abstinence-only messaging dominates sex education, media become a source to which young people turn and where they receive much of their sex-based messaging. Due to backlash over problematic content that perpetuates gender stereotypes and relays harmful messages about sex and sexuality, some magazines, including Teen Vogue, have attempted to shift towards more feminist-minded content (Keller, 2011, Milkie, 2002). This study is a qualitative critical feminist media analysis that examined the framing of sex, sexuality, and reproduction content in a sample of 60 Teen Vogue articles, an online publication that targets adolescents and young adults. The analysis revealed that overall, articles conveyed positive representations of sexuality, advocating for affirming and evidence-based sex education, self-empowerment through knowledge, and comprehensive reproductive healthcare for all. However, contradictory frames of sex stigmatization and a reproductive rights framework that advocates primarily for abortion rights were still highly prevalent in the data. Considering media is a significant component of the sexual socialization of youth, Sex Positive framing of sexuality which prioritizes pleasure, healthy relationships and sexual dynamics, and inclusive and affirmative sex education helps to create new narratives in media concerning how sex is viewed. These messages may have positive impacts by creating healthier sexual scripts and becoming dominant narratives in the future. However, articles in the data also utilized fear-mongering tactics that are notoriously used in abstinence-only sex education. These messages aid in further stigmatizing young people not only for having sex but also for not being informed of the potential associated risks, creating a harmful paradox that may counteract the goals of sexual health and sex positivity. Additionally, reproductive rights and reproductive justice messaging and the presentation of policy updates relevant to young readers has the potential to inform and socialize young people to be better informed about sex and sexuality, which may, in turn, lead to greater sexual empowerment. Such messaging may also empower youth activists in a time of political turmoil, connecting teen readers to what is going on around them, and providing concrete actions they can take to create political change. ?
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Date Issued: 2019
Identifier: CFE0007832, ucf:52815
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007832

Title: Scalable Map Information Dissemination for Connected and Automated Vehicle Systems.
Creator: Gani, S M Osman, Pourmohammadi Fallah, Yaser, Vosoughi, Azadeh, Yuksel, Murat, Chatterjee, Mainak, Hasan, Samiul, University of Central Florida
Abstract / Description: Situational awareness in connected and automated vehicle (CAV) systems becomes particularly challenging in the presence of non-line of sight objects and/or objects beyond the sensing range of local onboard sensors. Despite the fact that fully autonomous driving requires the use of multiple redundant sensor systems, primarily including camera, radar, and LiDAR, the non-line of sight object detection problem still persists due to the inherent limitations of those sensing techniques. To tackle...
Show moreSituational awareness in connected and automated vehicle (CAV) systems becomes particularly challenging in the presence of non-line of sight objects and/or objects beyond the sensing range of local onboard sensors. Despite the fact that fully autonomous driving requires the use of multiple redundant sensor systems, primarily including camera, radar, and LiDAR, the non-line of sight object detection problem still persists due to the inherent limitations of those sensing techniques. To tackle this challenge, the inter-vehicle communication system is envisioned that allows vehicles to exchange self-status updates aiming to extend their effective field of view and thus compensate for the limitations of the vehicle tracking subsystem that relies substantially on onboard sensing devices. Tracking capability in such systems can be further improved through the cooperative sharing of locally created map data instead of transmitting only self-update messages containing core basic safety message (BSM) data. In the cooperative sharing of safety messages, it is imperative to have a scalable communication protocol to ensure optimal use of the communication channel. This dissertation contributes to the analysis of the scalability issue in vehicle-to-everything (V2X) communication and then addresses the range issue of situational awareness in CAV systems by proposing a content-adaptive V2X communication architecture. To that end, we first analyze the BSM scheduling protocol standardized in the SAE J2945/1 and present large-scale scalability results obtained from a high-fidelity simulation platform to demonstrate the protocol's efficacy to address the scalability issues in V2X communication. By employing a distributed opportunistic approach, the SAE J2945/1 congestion control algorithm keeps the overall offered channel load within an optimal operating range, while meeting the minimum tracking requirements set forth by upper-layer applications. This scheduling protocol allows event-triggered and vehicle-dynamics driven message transmits that further the situational awareness in a cooperative V2X context. Presented validation results of the congestion control algorithm include position tracking errors as the performance measure, with the age of communicated information as the evaluation measure. In addition, we examine the optimality of the default settings of the congestion control parameters. Comprehensive analysis and trade-off study of the control parameters reveal some areas of improvement to further the algorithm's efficacy. Motivated by the effectiveness of channel congestion control mechanism, we further investigate message content and length adaptations, together with transmit rate control. Reasonably, the content of the exchanged information has a significant impact on the map accuracy in cooperative driving systems. We investigate different content control schemes for a communication architecture aimed at map sharing and evaluate their performance in terms of position tracking error. This dissertation determines that message content should be concentrated to mapped objects that are located farther away from the sender to the edge of the local sensor range. This dissertation also finds that optimized combination of message length and transmit rate ensures the optimal channel utilization for cooperative vehicular communication, which in turn improves the situational awareness of the whole system.
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Date Issued: 2019
Identifier: CFE0007634, ucf:52470
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007634

Title: Effluent Water Quality Improvement Using Silt Fences and Stormwater Harvesting.
Creator: Gogo-Abite, Ikiensinma, Chopra, Manoj, Wanielista, Martin, Nam, Boo Hyun, Weishampel, John, University of Central Florida
Abstract / Description: Construction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and...
Show moreConstruction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and other impervious surfaces are routinely discharged into ponds for treatment before being released into a receiving water body. Stormwater harvesting from a pond for irrigation of adjacent lands is promoted as one approach to reducing pond discharge while supplementing valuable potable water used for irrigation. The reduction of pond discharge reduces the mass of pollutants in the discharge. In the dissertation, presented is the investigation of the effectiveness of temporary sediment barriers and then, development of a modeling approach to a stormwater harvesting pond to provide a comprehensive stormwater management pollution reduction assessment tool.The first part of the research presents the investigation of the performance efficiencies of silt fence fabrics in turbidity and sediment concentration removal, and the determination of flow-through-rate on simulated construction sites in real time. Two silt fence fabrics, (1) woven and the other (2) nonwoven were subjected to material index property tests and a series of field-scale tests with different rainfall intensities and events for different embankment slopes on a tilting test-bed. Collected influent and effluent samples were analyzed for sediment concentration and turbidity, and the flow-through-rate for each fabric was evaluated. Test results revealed that the woven and nonwoven silt fence achieved 11 and 56 percent average turbidity reduction efficiency, respectively. Each fabric also achieved 20 and 56 percent average sediment concentration removal efficiency, respectively. Fabric flow-through-rates were functions of the rainfall intensity and embankment slope. The nonwoven fabric exhibited higher flow-through-rates than the woven fabric in both field-scale and laboratory tests.In the second part of the study, a Stormwater Harvesting and Assessment for Reduction of Pollution (SHARP) model was developed to predict operation of wet pond used for stormwater harvesting. The model integrates the interaction of surface water and groundwater in a catchment area. The SHARP model was calibrated and validated with actual pond water elevation data from a stormwater pond at Miramar Lakes, Miramar, Florida. Model evaluation showed adequate prediction of pond water elevation with root mean square error between 0.07 and 0.12 m; mean absolute error was between 0.018 and 0.07 m; and relative index of agreement was between 0.74 and 0.98 for both calibration and validation periods. The SHARP model is capable of assessing harvesting safe-yield and discharge from a pond, including the prediction of the percentage of runoff into a harvesting pond that is not discharged.The combination of silt fence and/or polyacrylamide PAM before stormwater harvesting pond in a treatment train for the reduction of pollutants from construction sites has the potential of significantly exceeding a performance standard of 85 percent reduction typically required by local authorities. In fact, the stringent requirement of equaling pre- and post-development pollutant loading is highly achievable by the treatment train approach. The significant contribution from the integration of the SHARP model to the treatment train is that real-time assessment of pollutant loading reduction by volume can be planned and controlled to achieve target performance standards.
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Date Issued: 2012
Identifier: CFE0004539, ucf:49244
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004539

Title: Infectious Disease Risks in Developing Countries: A Non-Market Valuation Exercise.
Creator: Samajpati, Shreejata, Gerking, Shelby, Dickie, Mark, Caputo, Michael, Roy, Joyashree, University of Central Florida
Abstract / Description: This dissertation focuses on the non-market valuation of health-risks of malaria, an infectious disease that imposes a substantive public health burden across the globe, hitting particularly hard the tropical developing nations of Africa and Asia. The United Nations Millennium Development Goals include malaria control as a priority and large investments are underway to promote effective prevention and treatment. Despite such concerted supply-side efforts, malaria-related mortality and...
Show moreThis dissertation focuses on the non-market valuation of health-risks of malaria, an infectious disease that imposes a substantive public health burden across the globe, hitting particularly hard the tropical developing nations of Africa and Asia. The United Nations Millennium Development Goals include malaria control as a priority and large investments are underway to promote effective prevention and treatment. Despite such concerted supply-side efforts, malaria-related mortality and morbidity still abound due to a complex interface of factors like climate-change, poverty, inadequate control behavior, infection and prevention externalities, parasite resistance etc. This research project digs into the demand-side of the health problem, considers the "externality" dimension to prevention, and primarily asks the question: how do individuals in developing countries view competing disease-control (prevention) measures, viz. a publicly-administered community-level malaria control measure as against private preventive choices. A theoretical model is developed to help explore the public-private interplay of health risks of malaria. The malaria-endemic regions of Kolkata (India) and its rural fringes comprise the site for an empirical investigation. A field survey (Malaria Risk and Prevention Survey, October-December, 2011) incorporating a mix of stated and revealed preference techniques of health valuation is implemented. Risk-perceptions of respondents are elicited using a measurable visual-aid and individuals' perceived valuations of health-risk reductions, randomly offered with the public and private health treatments, are empirically ascertained. Using a Likelihood Ratio Test on the structural risk parameters, it is seen that individuals' valuations of health risk reductions are the same across the private and public treatments. The comparative valuation exercise, thus, corroborates the externality dimension to malaria control, calling for greater public action to combat malaria. The viability of such a scaled-up public malaria program, in the context of Kolkata, is discussed by comparing the public treatment willingness to pay estimates with the annual estimated costs that the Kolkata Municipal Corporation, the civic body in the city of Kolkata, maintains on account of vector control. Results from the comparative valuation exercises also support the idea that private prevention is generally responsive to prevention costs, indicating the importance of price incentives to induce greater prevention. The issues of health valuation and price sensitivity are further explored across various split-samples differentiated on the basis of socio-economic attributes, disease exposure, actual prevention efforts and perceived malaria risks of survey respondents. Such auxiliary exercises help analyze the valuation question in greater depth, and generate policy insights into the potential factors that shape private prevention behavior.
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Date Issued: 2012
Identifier: CFE0004594, ucf:49195
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004594

Title: The Response of American Police Agencies to Digital Evidence.
Creator: Yesilyurt, Hamdi, Wan, Thomas, Potter, Roberto, Applegate, Brandon, Lang, Sheau-Dong, University of Central Florida
Abstract / Description: Little is known about the variation in digital forensics practice in the United States as adopted by large local police agencies. This study investigated how environmental constraints, contextual factors, organizational complexity, and organizational control relate to the adoption of digital forensics practice. This study integrated 3 theoretical perspectives in organizational studies to guide the analysis of the relations: institutional theory, contingency theory, and adoption-of-innovation...
Show moreLittle is known about the variation in digital forensics practice in the United States as adopted by large local police agencies. This study investigated how environmental constraints, contextual factors, organizational complexity, and organizational control relate to the adoption of digital forensics practice. This study integrated 3 theoretical perspectives in organizational studies to guide the analysis of the relations: institutional theory, contingency theory, and adoption-of-innovation theory. Institutional theory was used to analyze the impact of environmental constraints on the adoption of innovation, and contingency theory was used to examine the impacts of organizational control on the adoption of innovation. Adoption of innovation theory was employed to describe the degree to which digital forensics practice has been adopted by large municipal police agencies having 100 or more sworn police officers.The data set was assembled primarily by using Law Enforcement Management and Administrative Statistics (LEMAS) 2003 and 1999. Dr. Edward Maguire`s survey was used to obtain 1 variable. The joining up of the data set to construct the sample resulted in 345 large local police agencies. The descriptive results on the degree of adoption of digital forensics practice indicate that 37.7% of large local police agencies have dedicated personnel to address digital evidence, 32.8% of police agencies address digital evidence but do not have dedicated personnel, and only 24.3% of police agencies have a specialized unit with full-time personnel to address digital evidence. About 5% of local police agencies do nothing to address digital evidence in any circumstance. These descriptive statistics indicate that digital evidence is a matter of concern for most large local police agencies and that they respond to varying degrees to digital evidence at the organizational level. Agencies that have not adopted digital forensics practice are in the minority. The structural equation model was used to test the hypothesized relations, easing the rigorous analysis of relations between latent constructs and several indicator variables. Environmental constraints have the largest impact on the adoption of innovation, exerting a positive influence. No statistically significant relation was found between organizational control and adoption of digital forensic practice. Contextual factors (task scope and personnel size) positively influence the adoption of digital forensics. Structural control factors, including administrative weight and formalization, have no significant influence on the adoption of innovation. The conclusions of the study are as follows. Police agencies adopt digital forensics practice primarily by relying on environmental constraints. Police agencies exposed to higher environmental constraints are more frequently expected to adopt digital forensics practice. Because organizational control of police agencies is not significantly related to digital forensics practice adoption, police agencies do not take their organizational control extensively into consideration when they consider adopting digital forensics practice. The positive influence of task scope and size on digital forensics practice adoption was expected. The extent of task scope and the number of personnel indicate a higher capacity for police agencies to adopt digital forensics practice. Administrative weight and formalization do not influence the adoption of digital forensics practice. Therefore, structural control and coordination are not important for large local police agencies to adopt digital forensics practice.The results of the study indicate that the adoption of digital forensics practice is based primarily on environmental constraints. Therefore, more drastic impacts on digital forensics practice should be expected from local police agencies' environments than from internal organizational factors. Researchers investigating the influence of various factors on the adoption of digital forensics practice should further examine environmental variables. The unexpected results concerning the impact of administrative weight and formalization should be researched with broader considerations.
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Date Issued: 2011
Identifier: CFE0004181, ucf:49081
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004181

Title: A mathematical model for feral cat ecology with application to disease.
Creator: Sharpe, Jeff, Nevai, A, Shuai, Zhisheng, Qi, Yuanwei, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: We formulate and analyze a mathematical model for feral cats living in an isolated colony. The model contains compartments for kittens, adult females and adult males. Kittens are born at a rate proportional to the population of adult females and mature at equal rates into adult females and adult males. Adults compete with each other in a manner analogous to Lotka-Volterra competition. This competition comes in four forms, classified by gender. Native house cats, and their effects are also...
Show moreWe formulate and analyze a mathematical model for feral cats living in an isolated colony. The model contains compartments for kittens, adult females and adult males. Kittens are born at a rate proportional to the population of adult females and mature at equal rates into adult females and adult males. Adults compete with each other in a manner analogous to Lotka-Volterra competition. This competition comes in four forms, classified by gender. Native house cats, and their effects are also considered, including additional competition and abandonment into the feral population. Control measures are also modeled in the form of per-capita removal rates. We compute the net reproduction number (R_0) for the colony and consider its influence. In the absence of abandonment, if R_0(>)1, the population always persists at a positive equilibrium and if R_0 (<)= 1, the population always tends toward local extinction. This work will be referred to as the core model.The model is then expanded to include a set of colonies (patches) such as those in the core model (this time neglecting the effect of abandonment). Adult females and kittens remain in their native patch while adult males spend a fixed proportion of their time in each patch. Adult females experience competition from both the adult females living in the same patch as well as the visiting adult males. The proportion of adult males in patch j suffer competition from both adult females resident to that patch as well the proportion of adult males also in the patch. We formulate a net reproduction number for each patch (a patch reproduction number) R_j. If R_j(>)1 for at least one patch, then the collective population always persists at some nontrivial (but possibly semitrivial) steady state. We consider the number of possible steady states and their properties. This work will be referred to as the patch model.Finally, the core model is expanded to include the introduction of the feline leukemia virus. Since this disease has many modes of transmission, each of which depends on the host's gender and life-stage, we regard this as a model disease. A basic reproduction number R_0 for the disease is defined and analyzed. Vaccination terms are included and their role in disease propagation is analyzed. Necessary and sufficient conditions are given under which the disease-free equilibrium is stable.
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Date Issued: 2016
Identifier: CFE0006502, ucf:51389
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006502

Control (7)	+ -
control (7)	+ -
Digital Control (6)	+ -
simulation (5)	+ -
Adaptive Control (4)	+ -

Robotics (4)	+ -
cooperative control (4)	+ -
digital control (4)	+ -
locus of control (4)	+ -
Control Systems (3)	+ -
Motor Control (3)	+ -
Noise control (3)	+ -
corrosion control (3)	+ -
corrosion inhibitor (3)	+ -
gender (3)	+ -
gun control (3)	+ -
intimate partner violence (3)	+ -
modeling (3)	+ -
nonholonomic (3)	+ -
optimal control (3)	+ -
robust control (3)	+ -
social control (3)	+ -
soft switching (3)	+ -
workload (3)	+ -
Adolescents (2)	+ -
Bandwidth (2)	+ -
Cerebellum (2)	+ -
Compatibilism (2)	+ -
Cooperative Control (2)	+ -
Corrosion (2)	+ -

ETD Collection (183)	+ -
Honors Collection (18)	+ -
PRISM: Political & Rights Issues & Social Movements (2)	+ -

University of Central Florida (195)	+ -
Batarseh, Issa (18)	+ -
Qu, Zhihua (16)	+ -
Xu, Yunjun (15)	+ -
Haralambous, Michael (13)	+ -

Behal, Aman (12)	+ -
Lin, Kuo-Chi (12)	+ -
Das, Tuhin (11)	+ -
Simaan, Marwan (8)	+ -
Kassab, Alain (7)	+ -
Corzine, Harold (5)	+ -
Kutkut, Nasser (5)	+ -
Sundaram, Kalpathy (5)	+ -
Arnold, Vicky (4)	+ -
Duranceau, Steven (4)	+ -
Engineering (4)	+ -
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Huff-Corzine, Lin (4)	+ -
Jasinski, Jana (4)	+ -
Kauffman, Jeffrey (4)	+ -
Reckdenwald, Amy (4)	+ -
Sims, Valerie (4)	+ -
Vosoughi, Azadeh (4)	+ -
Wu, Xinzhang (4)	+ -
Xu, Chengying (4)	+ -
Yuan, Jiann-Shiun (4)	+ -
Abdel-Aty, Mohamed (3)	+ -
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