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Predictive Modeling Of Sulfide Removal In Tray Aerators, Jumoke O. Faborode 2010 University of Central Florida

Predictive Modeling Of Sulfide Removal In Tray Aerators, Jumoke O. Faborode

Electronic Theses and Dissertations

Hydrogen sulfide is commonly found in many Florida potable groundwater supplies. Removing sulfur species, particularly hydrogen sulfide is important because if left untreated, sulfide can impact finished water quality, corrosivity, create undesirable taste and odor, and oxidize to form visible turbidity and color. This document presents the results of a study designed to investigate the removal efficiencies of a variety of tray aerators in Central Florida in order to develop a predictive mathematical model that could be used to determine tray effectiveness for sulfide removal. A literature review was performed that indicated there was limited information regarding the removal of ...


Learning From Geometry In Learning For Tactical And Strategic Decision Domains, Jason Gauci 2010 University of Central Florida

Learning From Geometry In Learning For Tactical And Strategic Decision Domains, Jason Gauci

Electronic Theses and Dissertations

Artificial neural networks (ANNs) are an abstraction of the low-level architecture of biological brains that are often applied in general problem solving and function approximation. Neuroevolution (NE), i.e. the evolution of ANNs, has proven effective at solving problems in a variety of domains. Information from the domain is input to the ANN, which outputs its desired actions. This dissertation presents a new NE algorithm called Hypercube-based NeuroEvolution of Augmenting Topologies (HyperNEAT), based on a novel indirect encoding of ANNs. The key insight in HyperNEAT is to make the algorithm aware of the geometry in which the ANNs are embedded ...


A Taxonomy Of Lean Six Sigma Success Factors For Service Organizations, Reza N. Hajikordestani 2010 University of Central Florida

A Taxonomy Of Lean Six Sigma Success Factors For Service Organizations, Reza N. Hajikordestani

Electronic Theses and Dissertations

Six Sigma is a business improvement strategy that aims to improve process performance using a structured methodology that identifies and removes the causes of defects in manufacturing and business processes, while implementing the lean concepts attempts to remove wasteful activities from those processes. In practice, the Six Sigma strategy and the Lean philosophy are combined and often viewed as one integrated philosophy, where the philosophy of Lean Six Sigma simultaneously removes wasteful activities from a process and reduces the variability of that process. This thesis research reviews the concepts and implementation of Lean thinking, Six Sigma strategy, and the integrated ...


Fast-Response Liquid Crystal Displays, Meizi Jiao 2010 University of Central Florida

Fast-Response Liquid Crystal Displays, Meizi Jiao

Electronic Theses and Dissertations

After about five decades of extensive material research and device development, followed by massive investment in manufacturing technology, thin-film-transistor liquid-crystaldisplay (TFT-LCD) has finally become the dominant flat panel display technology. Nowadays, LCD performances, such as viewing angle, contrast ratio, and resolution, have reached acceptable levels. The remaining major technical challenges are response time, light efficiency, and sunlight readability. Fast response time is desired to reduce motion blur and to enable field sequential color displays using red (R), green (G), and blue (B) LEDs (light emitting diodes) without noticeable color breakup. Sequential RGB colors would eliminate the commonly used spatial color ...


Thermal Performance Of Cryogenic Multilayer Insulation At Various Layer Spacings, Wesley Louis Johnson 2010 University of Central Florida

Thermal Performance Of Cryogenic Multilayer Insulation At Various Layer Spacings, Wesley Louis Johnson

Electronic Theses and Dissertations

Multilayer insulation (MLI) has been shown to be the best performing cryogenic insulation system at high vacuum (less than 10-3 torr), and is widely used on spaceflight vehicles. Over the past 50 years, many numerous investigations of MLI have yielded a general understanding of the many variables associated with MLI. MLI has been shown to be a function of variables such as warm boundary temperature, the number of reflector layers, and the spacer material in between reflectors, the interstitial gas pressure and the interstitial gas. Because conduction between reflectors increases with the thickness of the spacer material, and yet the ...


Effects Of Flight Factors On Pilot Performance, Workload, And Stress At Final Approach To Landing Phase Of Flight, Kyongsun Lee 2010 University of Central Florida

Effects Of Flight Factors On Pilot Performance, Workload, And Stress At Final Approach To Landing Phase Of Flight, Kyongsun Lee

Electronic Theses and Dissertations

Since human errors are one of the major causes of flight accidents, the design and operation of the modern aircraft system deals with them seriously. Particularly, the pilot workload on aviation causes human errors. Whenever new procedures are introduced and operated, the aircraft capabilities have been checked in every aspect. However, there has been little study on the impact of the new procedures such as LDLP, SCDA, SATS, and Steep Angle approach on the pilot performance, workload, and stress. In this study, different methods have been tried to understand the relationship between new procedures and the pilots in terms of ...


Optimized Market Introduction Of Large Capital Products (Lcp) With Long Development And Learning Cycles, Antje Lembcke 2010 University of Central Florida

Optimized Market Introduction Of Large Capital Products (Lcp) With Long Development And Learning Cycles, Antje Lembcke

Electronic Theses and Dissertations

Any product sold is expected to be reliable and available when the customer wants to operate it. Companies that produce large capital products (LCP), such as rockets, satellites, or large gas turbines to generate electrical energy, tend to shy away from extending their testing and validation method above the requirements by law, mainly due to the very high costs of each additional test and the uncertain return on investment. This research shows that today’s state of the art validation methods for LCP, required by law, or suggested in literature, and adapted by these industries, are not capable of capturing ...


Evaluating The Benefits Of 3d Stereo In Modern Video Games, Tad Litwiller 2010 University of Central Florida

Evaluating The Benefits Of 3d Stereo In Modern Video Games, Tad Litwiller

Electronic Theses and Dissertations

We present a study that investigates user performance benefits of 3D stereo in modern video games. Based on an analysis of several video games that are best suited for use with commercial 3D stereo drivers and vision systems, we chose five modern titles focusing on racing, first person shooter, third person shooter, and sports game genres. For each game, quantitative and qualitative measures were taken to determine if users performed better and learned faster in the experimental group (3D stereo display) than in the control group (2D display). A game experience pre-questionnaire was used to classify participants into beginner, intermediate ...


Query Processing In Location-Based Services, Fuyu Liu 2010 University of Central Florida

Query Processing In Location-Based Services, Fuyu Liu

Electronic Theses and Dissertations

With the advances in wireless communication technology and advanced positioning systems, a variety of Location-Based Services (LBS) become available to the public. Mobile users can issue location-based queries to probe their surrounding environments. One important type of query in LBS is moving monitoring queries over mobile objects. Due to the high frequency in location updates and the expensive cost of continuous query processing, server computation capacity and wireless communication bandwidth are the two limiting factors for large-scale deployment of moving object database systems. To address both of the scalability factors, distributed computing has been considered. These schemes enable moving objects ...


Nonlinear Absorption And Free Carrier Recombination In Direct Gap Semiconductors, Peter D. Olszak 2010 University of Central Florida

Nonlinear Absorption And Free Carrier Recombination In Direct Gap Semiconductors, Peter D. Olszak

Electronic Theses and Dissertations

Nonlinear absorption of Indium Antimonide (InSb) has been studied for many years, yet due to the complexity of absorption mechanisms and experimental difficulties in the infrared, this is still a subject of research. Although measurements have been made in the past, a consistent model that worked for both picosecond and nanosecond pulse widths had not been demonstrated. In this project, temperature dependent two-photon (2PA) and free carrier absorption (FCA) spectra of InSb are measured using femtosecond, picosecond, and nanosecond IR sources. The 2PA spectrum is measured at room temperature with femtosecond pulses, and the temperature dependence of 2PA and FCA ...


Perceived Service Quality's Impact On Behavioral Intentions In The Timeshare Industry, Leonard Pollar II 2010 University of Central Florida

Perceived Service Quality's Impact On Behavioral Intentions In The Timeshare Industry, Leonard Pollar Ii

Electronic Theses and Dissertations

This study created a model using factor analysis and structural equation modeling to investigate the relationship of service quality, word-of-mouth recommendation and price sensitivity of individuals who experienced a timeshare mini vacation at a branded timeshare resort. The constructs of service quality were developed by creating a survey tool. A total of 4,797 surveys were electronically sent resulting in a total of 1,275 of the individuals surveyed who met the criteria of staying at a branded hotel or resort during their mini vacation. Six different variables were created from the ordinal level questions on the survey: Resort Accommodations ...


Conventional And Zvt Synchronous Buck Converter Design, Analysis, And Measurement, Mark Cory 2010 University of Central Florida

Conventional And Zvt Synchronous Buck Converter Design, Analysis, And Measurement, Mark Cory

Electronic Theses and Dissertations

The role played by power converting circuits is extremely important to almost any electronic system built today. Circuits that use converters of any type depend on power that is consistent in form and reliable in order to properly function. In addition, today's demands require more efficient use of energy, from large stationary systems such as power plants all the way down to small mobile devices such as laptops and cell phones. This places a need to reduce any losses to a minimum. The power conversion circuitry in a system is a very good place to reduce a large amount ...


Transfer And Development Length Of Strands In Post-Tensioned Members After Anchor Head Failure, Elie El Zghayar 2010 University of Central Florida

Transfer And Development Length Of Strands In Post-Tensioned Members After Anchor Head Failure, Elie El Zghayar

Electronic Theses and Dissertations

Post-tensioning tendons in segmental bridge construction are often only anchored within the deviator and pier segments. The effectiveness of the post-tensioning (PT) system is therefore dependent on proper functioning of the anchorages. On August 28, 2000 a routine inspection of the Mid-Bay Bridge (Okaloosa County, Florida) revealed corrosion in numerous PT tendons. Moreover, one of the 19-strand tendons was completely slacked, with later inspection revealing a corrosion-induced failure at the pier anchor location. Anchorage failure caused all PT force to transfer to the steel duct located within the pier segment that in turn slipped and caused the tendon to go ...


A Study Of The Strength Of Pervious Pavement Systems, Ikenna Uju 2010 University of Central Florida

A Study Of The Strength Of Pervious Pavement Systems, Ikenna Uju

Electronic Theses and Dissertations

This thesis presents a study on the strength properties of the different pervious pavement systems installed at the Stormwater Management Academy field laboratory at University of Central Florida (UCF), Orlando. The strength tests were performed both in the laboratory and in the field. Laboratory testing was conducted to determine the compressive strength and flexural strength of the various pavement surfaces. Evaluation of field pavement performance was performed by comparing the deflection basins using the Falling Weight Deflectometer test on pervious concrete and porous asphalt with conventional impervious concrete and asphalt pavements of similar layer profile and thickness, respectively. From literature ...


Assessment Of Aquifer Storage And Recovery Impact On Phosphorus Stability In Lake Sediment, Sha Liu 2010 University of Central Florida

Assessment Of Aquifer Storage And Recovery Impact On Phosphorus Stability In Lake Sediment, Sha Liu

Electronic Theses and Dissertations

Lake Okeechobee, the second largest natural freshwater lake in the United States, had experienced a historical drought in 2007-2008 and the inflow to Lake Okeechobee has been reduced by 40% of the average daily mean between warm phase and cold phase due to the impact of Atlantic Multidecadal Oscillation in the past six decades. To cope with this water resources management problem, the US Army Corps of Engineers (USACE) proposed the largest national implementation plan of aquifer storage and recovery (ASR) project in the Kissimmee River Basin. Routine operation of ASR will deliver recovered water from ASR wells into the ...


Analysis Of The Florida's Showcase Green Envirohome Water/Wastewater Systems And Development Of A Cost-Benefit Green Roof Optimization Model, Brian Rivera 2010 University of Central Florida

Analysis Of The Florida's Showcase Green Envirohome Water/Wastewater Systems And Development Of A Cost-Benefit Green Roof Optimization Model, Brian Rivera

Electronic Theses and Dissertations

The Florida Showcase Green Envirohome (FSGE) incorporates many green technologies. FSGE is built to meet or exceed 12 green building guidelines and obtain 8 green building certificates. The two-story 3292 ft2 home is a "Near Zero-Loss Home", "Near Zero-Energy Home", "Near Zero-Runoff Home", and "Near Zero-Maintenance Home". It is spawned from the consumer-driven necessity to build a home resistant to hurricanes, tornadoes, floods, fire, mold, termites, impacts, and even earthquakes given up to 500% increase in insurance premiums in natural disaster zones, the dwindling flexibility and coverage of insurance policies, and rising energy, water and maintenance costs (FSGE 2008). The ...


Evaluation Of Oxidized Media Filtration Processes For The Treatment Of Hydrogen Sulfide In Groundwater, Vito Trupiano 2010 University of Central Florida

Evaluation Of Oxidized Media Filtration Processes For The Treatment Of Hydrogen Sulfide In Groundwater, Vito Trupiano

Electronic Theses and Dissertations

This study evaluated alternative sulfide treatment processes for potable water systems that rely on groundwater supplies. Research for this study was conducted at the Imperial Lakes (IL) and Turner Road (TR) water treatment plants (WTPs) in Polk County, Florida. These WTPs are in the process of refurbishment and expansion, and will require the installation of a new groundwater well. The IL and TR WTPs both rely upon groundwater sources that contain total sulfide at concentrations ranging from 1.4 to 2.6 mg/L. Sulfide is a concern because if left untreated it can impact finished water quality, corrosivity, create ...


Designing Of Energy Efficient Indoor Environments Using A Localized Radial Basis Function Meshless Method, Victor Huayamave 2010 University of Central Florida

Designing Of Energy Efficient Indoor Environments Using A Localized Radial Basis Function Meshless Method, Victor Huayamave

Electronic Theses and Dissertations

Around the world, the energy over consumption issue has been one of the key socio-economic and political challenges, which has drastically worsened over the last few years. Over the years engineers and environmentalists have proposed several approaches to improve energy efficiency. One is to reduce energy demand by improving consumption habits and a second approach is to introduce the use of a "greener" concept by using biomaterials in a diverse and more efficient manner in engineering construction to create energy efficient environments. This work will investigate the effects of using "green" stabilized earth materials to provide and enhance thermal regulation ...


Thermal Detection Of Biomarkers Using Phase Change Nanoparticles, Chaoming Wang 2010 University of Central Florida

Thermal Detection Of Biomarkers Using Phase Change Nanoparticles, Chaoming Wang

Electronic Theses and Dissertations

Most of existing techniques cannot be used to detect molecular biomarkers (i.e., protein and DNA) contained in complex body fluids due to issues such as enzyme inhibition or signal interference. This thesis describes a nanoparticle-based thermal detection method for the highly sensitive detections of multiple DNA biomarkers or proteins contained in different type of fluids such as buffer solution, cell lysate and milk by using solid-liquid phase change nanoparticles as thermal barcodes. Besides, this method has also been applied for thrombin detection by using RNA aptamer-functionalized phase change nanoparticles as thermal probes. Furthermore, using nanostructured Si surface that have ...


Vaporization Characteristics Of Pure And Blended Biofuel Droplet Injected Into Hot Stream Of Air, Abhishek Saha 2010 University of Central Florida

Vaporization Characteristics Of Pure And Blended Biofuel Droplet Injected Into Hot Stream Of Air, Abhishek Saha

Electronic Theses and Dissertations

The combustion dynamics and stability are dependent on the quality of mixing and vaporization of the liquid fuel in the pre-mixer. The vaporization characteristics of different blends of biofuel droplets injected into the air stream in the pre-mixer are modeled in this current study. The focus of this work is on the blended alternate fuels which are lately being considered for commercial use. Two major alternate fuels analyzed are ethanol and Rapeseed Methyl Esters (RME). Ethanol is being used as a substitute for gasoline, while RME is an alternative for diesel. In the current work, the vaporization characteristics of a ...


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