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2008

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Hydrogen Peroxide Formation Rates In A Pemfc Anode And Cathode: Effect Of Humidity And Temperature, Vijay A. Sethuraman, John W. Weidner, Andrew T. Haug, Sathya Motupally, Lesia V. Protsailo Jan 2008

Hydrogen Peroxide Formation Rates In A Pemfc Anode And Cathode: Effect Of Humidity And Temperature, Vijay A. Sethuraman, John W. Weidner, Andrew T. Haug, Sathya Motupally, Lesia V. Protsailo

Faculty Publications

Hydrogen peroxide (H2O2) formation rates in a proton exchange membrane fuel cell (PEMFC) anode and cathode were estimated as a function of humidity and temperature by studying the oxygen reduction reaction (ORR) on a rotating ring disk electrode. Fuel cell conditions were replicated by depositing a film of Pt/Vulcan XC-72 catalyst onto the disk and by varying the temperature, dissolved O2 concentration, and the acidity levels in hydrochloric acid (HClO4). The HClO4 acidity was correlated to ionomer water activity and hence fuel cell humidity. The H2O2 formation rates showed …

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The Impact Of Incorporating Specific Literacy Strategies In A Mathematics Classroom, Katherine Rudnicki Jan 2008

The Impact Of Incorporating Specific Literacy Strategies In A Mathematics Classroom, Katherine Rudnicki

Mathematical and Computing Sciences Masters

This research study looked at the impact of incorporating specific literacy strategies into a mathematics classroom. The literacy strategies used in this study included graphic organizers, connecting picture books to math content, summarizing and think aloud techniques, and student journals for reflection. The strategies used were beneficial in promoting mathematical concepts and ideas in new and different ways. It was found that student engagement increased with the variety of strategies used. Student vocabulary and classroom discussion began to develop in a positive way in terms of accuracy and insightfulness as a result of the literacy strategies used. Implementation of the …

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Exploring Mathematics Assessments, Kelley Barz Jan 2008

Exploring Mathematics Assessments, Kelley Barz

Mathematical and Computing Sciences Masters

Students will take more than one type of assessment throughout their educational career. It is the teacher' s job to determine which type of assessment will help their students achieve success. The researcher believes that the state of Virginia has a limited amount of alternative assessments for students with special needs. She decided to investigate which types of assessments would be effective for her students. The children who participated in this study are students who receive special education and English as a Second or Other Language (ESOL) services. The researcher created several alternative mathematics assessments and administered them to four …

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Leaving The Traditional Classroom: A Look At Direct Instruction Versus Differentiated Instruction, Robert D. Dunham Jan 2008

Leaving The Traditional Classroom: A Look At Direct Instruction Versus Differentiated Instruction, Robert D. Dunham

Mathematical and Computing Sciences Masters

The purpose of this study is to determine the effect of pedagogy on a students' performance on their formal assessment at the end of a unit. In the literature review direct instruction and differentiated instruction are compared and contrasted as the articles are synthesized to offer insight on the opposing views of instruction. In this study two classes were taught the same content for a unit; one class was taught by direct instruction while the other class was taught via differentiated instruction. Results indicated that students can be successful in learning the content no matter which method was used to …

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Using Strategies To Aid In Mathematical Problem Solving, Jennifer A. Smith Jan 2008

Using Strategies To Aid In Mathematical Problem Solving, Jennifer A. Smith

Mathematical and Computing Sciences Masters

Students across the state are taking standardized mathematics assessments. Their scores on these assessments determine their schedule for the following year, as well as contribute to district, regional and state wide data. These assessments tend to consist of questions that are made up of word problems used to see if a student understands the content. The purpose of this study is to provide students with literacy strategies to help them gain a greater understanding of the word problem and allow them to more successfully answer the questions. Through the study students were presented with three literacy strategies, using key vocabulary …

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History In The Making (Volume 1), Csusb - Alpha Delta Nu Chapter Of The Phi Alpha Theta National History Honor Society Jan 2008

History In The Making (Volume 1), Csusb - Alpha Delta Nu Chapter Of The Phi Alpha Theta National History Honor Society

History in the Making

No abstract provided.

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Relationship Between Self-Reported Lifestyle Habits, Social Support, And Physiological Factors Associated With Hypertension : A Biopsychosocial Investigation, Deborah A. Chiumento Jan 2008

Relationship Between Self-Reported Lifestyle Habits, Social Support, And Physiological Factors Associated With Hypertension : A Biopsychosocial Investigation, Deborah A. Chiumento

PCOM Psychology Dissertations

The relationship between hypertension and related biological, psychological, and social variables among patients diagnosed with hypertension was investigated utilizing the biopsychosocial model. Fifty-four participants from one outpatient private medical office were administered a demographic form, the Beck Anxiety Inventory (BAI), the Health Adherence Behavior Inventory (HABIT), the Inventory for Cognitive Distortions (ICD), and the Multidimensional Scale of Perceived Social Support (MSPSS). Results indicated that the participants' use of caffeine positively correlated with their high blood pressure readings. In addition, participants who reported having significant social support engaged in more health promoting behaviors. These findings were consistent with the hypotheses. Limitations …

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Reports From Fundamentalism’S Front Lines: ‘The Pilot’ And Its Correspondents, 1920-1947, William Vance Trollinger Jan 2008

Reports From Fundamentalism’S Front Lines: ‘The Pilot’ And Its Correspondents, 1920-1947, William Vance Trollinger

History Faculty Publications

Religion and the Culture of Print in Modern America explores how a variety of print media—religious tracts, newsletters, cartoons, pamphlets, self-help books, mass-market paperbacks, and editions of the Bible from the King James Version to contemporary "Bible-zines"—have shaped and been shaped by experiences of faith since the Civil War. Edited by Charles L. Cohen and Paul S. Boyer, whose comprehensive historical essays provide a broad overview to the topic, this book is the first on the history of religious print culture in modern America and a well-timed entry into the increasingly prominent contemporary debate over the role of religion in …

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Meshless Hemodynamics Modeling And Evolutionary Shape Optimization Of Bypass Grafts Anastomoses, Zaher El Zahab Jan 2008

Meshless Hemodynamics Modeling And Evolutionary Shape Optimization Of Bypass Grafts Anastomoses, Zaher El Zahab

Electronic Theses and Dissertations

Objectives: The main objective of the current dissertation is to establish a formal shape optimization procedure for a given bypass grafts end-to-side distal anastomosis (ETSDA). The motivation behind this dissertation is that most of the previous ETSDA shape optimization research activities cited in the literature relied on direct optimization approaches that do not guaranty accurate optimization results. Three different ETSDA models are considered herein: The conventional, the Miller cuff, and the hood models. Materials and Methods: The ETSDA shape optimization is driven by three computational objects: a localized collocation meshless method (LCMM) solver, an automated geometry pre-processor, and a genetic-algorithm-based …

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Stochastic Resource Constrained Project Scheduling With Stochastic Task Insertion Problems, Sandra Archer Jan 2008

Stochastic Resource Constrained Project Scheduling With Stochastic Task Insertion Problems, Sandra Archer

Electronic Theses and Dissertations

The area of focus for this research is the Stochastic Resource Constrained Project Scheduling Problem (SRCPSP) with Stochastic Task Insertion (STI). The STI problem is a specific form of the SRCPSP, which may be considered to be a cross between two types of problems in the general form: the Stochastic Project Scheduling Problem, and the Resource Constrained Project Scheduling Problem. The stochastic nature of this problem is in the occurrence/non-occurrence of tasks with deterministic duration. Researchers Selim (2002) and Grey (2007) laid the groundwork for the research on this problem. Selim (2002) developed a set of robustness metrics and used …

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Hurricane Evacuation: Origin, Route And Destination, Vinayak Dixit Jan 2008

Hurricane Evacuation: Origin, Route And Destination, Vinayak Dixit

Electronic Theses and Dissertations

Recent natural disasters have highlighted the need to evacuate people as quickly as possible. During hurricane Rita in 2005, people were stuck in queue buildups and large scale congestions, due to improper use of capacity, planning and inadequate response to vehicle breakdown, flooding and accidents. Every minute is precious in situation of such disaster scenarios. Understanding evacuation demand loading is an essential part of any evacuation planning. One of the factors often understood to effect evacuation, but not modeled has been the effect of a previous hurricane. This has also been termed as the 'Katrina Effect', where, due to the …

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Experimental Analysis Of The Hydrogen Sulfide Absortion Phenomena In Brine/Oil Mixtures As A Function Of System Pressure And H2s, Luis Zea Jan 2008

Experimental Analysis Of The Hydrogen Sulfide Absortion Phenomena In Brine/Oil Mixtures As A Function Of System Pressure And H2s, Luis Zea

Electronic Theses and Dissertations

In underground oil reservoirs, Hydrogen sulfide is usually found coexisting with the oil due to bacteria reduction over a long period of time. The amount of H2S in the oil varies from place to place around the globe. When the oil extraction process begins, the presence of Hydrogen sulfide becomes noticeable as drilling tools, piping and other equipment suffer from sulfide stress cracking, electrochemical corrosion and corrosion fatigue. For this reason, the oil industry invests millions of dollars per year trying to find better ways to reduce the amount of H2S in oil. An important part of the current investigations …

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The Acute Toxicity Of Ground Recycled Automobile Tires On Aquatic Life With Model Species P. Promelas, Trillian Baldassari Jan 2008

The Acute Toxicity Of Ground Recycled Automobile Tires On Aquatic Life With Model Species P. Promelas, Trillian Baldassari

Electronic Theses and Dissertations

Used tires have the potential for becoming popular in pollution control media used in stormwater applications including pervious pavement sub bases, green roof growth media, and upflow filters. Using tire crumb to decrease nutrients can minimize impacts on ecology while reducing the human footprint left by used tires. However, if tire crumb is not examined for toxicity, the ecological balance could unknowingly be disrupted. This research tested the acute toxicity of tire crumb in aquatic systems by finding the Lethal Concentration for 50% kill (LC50). Using an extreme tire crumb load, P. promelas (fathead minnow) were exposed to leachates created …

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Characteristics Of Red Light Running Crashesin Florida, Dina Elnashar Jan 2008

Characteristics Of Red Light Running Crashesin Florida, Dina Elnashar

Electronic Theses and Dissertations

Red light running is one of the main contributing factors of crashes in urban areas in Florida and the United States. Nationwide, according to preliminary estimates by the Federal Highway Administration (FHWA) 2001, there were nearly 218,000 red-light running crashes at intersections. These crashes resulted in as many as 181,000 injuries and 880 fatalities, and an economic loss estimated at $14 billion per year nationwide, According to the Community Traffic Safety Team Florida Coalition (A statewide traffic safety group) there were 9,348 crashes involving red-light running in Florida and 127 fatalities in 1999. This research study focused on studying the …

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The Calibration And Verification Of Simulation Models For Toll Plazas, Christopher Russo Jan 2008

The Calibration And Verification Of Simulation Models For Toll Plazas, Christopher Russo

Electronic Theses and Dissertations

A great deal of research has been conducted on Central Florida toll roads to better understand the characteristics of the tolling operation. In this thesis, the development and calibration of a toll plaza simulation models will be analyzed using two simulation programs varying mostly in their modeling theory. The two models utilized are, SHAKER, a deterministic queuing model for vehicles utilizing toll collection facilities, and VISSIM, a globally popular stochastic simulation software. The benefits of simulation models leads to the purpose of this thesis, which is to examine the effectiveness of two toll modeling programs that are similar in purpose …

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Metadata And Data Management In High Performance File And Storage Systems, Peng Gu Jan 2008

Metadata And Data Management In High Performance File And Storage Systems, Peng Gu

Electronic Theses and Dissertations

With the advent of emerging "e-Science" applications, today's scientific research increasingly relies on petascale-and-beyond computing over large data sets of the same magnitude. While the computational power of supercomputers has recently entered the era of petascale, the performance of their storage system is far lagged behind by many orders of magnitude. This places an imperative demand on revolutionizing their underlying I/O systems, on which the management of both metadata and data is deemed to have significant performance implications. Prefetching/caching and data locality awareness optimizations, as conventional and effective management techniques for metadata and data I/O performance enhancement, still play their …

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Automated Regression Testing Approach To Expansion And Refinement Of Speech Recognition Grammars, Raul Dookhoo Jan 2008

Automated Regression Testing Approach To Expansion And Refinement Of Speech Recognition Grammars, Raul Dookhoo

Electronic Theses and Dissertations

This thesis describes an approach to automated regression testing for speech recognition grammars. A prototype Audio Regression Tester called ART has been developed using Microsoft's Speech API and C#. ART allows a user to perform any of three tasks: automatically generate a new XML-based grammar file from standardized SQL database entries, record and cross-reference audio files for use by an underlying speech recognition engine, and perform regression tests with the aid of an oracle grammar. ART takes as input a wave sound file containing speech and a newly created XML grammar file. It then simultaneously executes two tests: one with …

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Evaluation Of Climatic And Ecohydrological Effects On Longwave Radiation And Evapotranspiration, Maria Rizou Jan 2008

Evaluation Of Climatic And Ecohydrological Effects On Longwave Radiation And Evapotranspiration, Maria Rizou

Electronic Theses and Dissertations

Modern tools, nontraditional datasets and a better understanding of the interaction between climate and ecohydrology are continuously being developed as today's society is in critical need for improving water management, predicting hydrometeorological hazards and forecasting future climate. In particular, the study of the intra- and inter-annual variations in grass productivity and evapotranspiration caused by variations in precipitation/soil moisture and other biophysical factors is of great significance due to their relation to future climatic changes. The research presented here falls in three parts. In the first part of the dissertation, a land use adaptable model, based on the superposition of the …

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Sustainable Fault-Handling Of Reconfigurable Logic Using Throughput-Driven Assessment, Carthik Sharma Jan 2008

Sustainable Fault-Handling Of Reconfigurable Logic Using Throughput-Driven Assessment, Carthik Sharma

Electronic Theses and Dissertations

A sustainable Evolvable Hardware (EH) system is developed for SRAM-based reconfigurable Field Programmable Gate Arrays (FPGAs) using outlier detection and group testing-based assessment principles. The fault diagnosis methods presented herein leverage throughput-driven, relative fitness assessment to maintain resource viability autonomously. Group testing-based techniques are developed for adaptive input-driven fault isolation in FPGAs, without the need for exhaustive testing or coding-based evaluation. The techniques maintain the device operational, and when possible generate validated outputs throughout the repair process. Adaptive fault isolation methods based on discrepancy-enabled pair-wise comparisons are developed. By observing the discrepancy characteristics of multiple Concurrent Error Detection (CED) configurations, …

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Modeling Lane-Based Traffic Flow In Emergency Situations In The Presence Of Multiple Heterogeneous Flows, Amani Saleh Jan 2008

Modeling Lane-Based Traffic Flow In Emergency Situations In The Presence Of Multiple Heterogeneous Flows, Amani Saleh

Electronic Theses and Dissertations

In recent years, natural, man-made and technological disasters have been increasing in magnitude and frequency of occurrence. Terrorist attacks have increased after the September 11, 2001. Some authorities suggest that global warming is partly the blame for the increase in frequency of natural disasters, such as the series of hurricanes in the early-2000's. Furthermore, there has been noticeable growth in population within many metropolitan areas not only in the US but also worldwide. These and other facts motivate the need for better emergency evacuation route planning (EERP) approaches in order to minimize the loss of human lives and property. This …

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Alayzing The Effects Of Modularity On Search Spaces, Ozlem Garibay Jan 2008

Alayzing The Effects Of Modularity On Search Spaces, Ozlem Garibay

Electronic Theses and Dissertations

We are continuously challenged by ever increasing problem complexity and the need to develop algorithms that can solve complex problems and solve them within a reasonable amount of time. Modularity is thought to reduce problem complexity by decomposing large problems into smaller and less complex subproblems. In practice, introducing modularity into evolutionary algorithm representations appears to improve search performance; however, how and why modularity improves performance is not well understood. In this thesis, we seek to better understand the effects of modularity on search. In particular, what are the effects of module creation on the search space structure and how …

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Comparison Of Theoretical Models Of Power Spectral Density To The Experimental Value For Spectrum Of Irradiance Fluctuations, Craig Hershberger Jan 2008

Comparison Of Theoretical Models Of Power Spectral Density To The Experimental Value For Spectrum Of Irradiance Fluctuations, Craig Hershberger

Electronic Theses and Dissertations

A propagation experiment was designed, assembled, and conducted on an extended range to verify theoretical temporal models for weak to strong fluctuation theory. Laser light intensity was propagated over terrain at the Kennedy Space Center (Florida), and detected using optical receivers at a distance of 13.3 Km from the optical source. The intensity data from the experiment was used to generate an experimental Power Spectral Density (PSD) function. The theoretical Mutual Coherence Function (MCF) and Wave Structure Function (WSF) as set forth by Andrews/Phillips , were evaluated to determine the effective relationship between the statistical moments of the random optical …

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Data Communication With A Nano-Satellite Using Satellite Personal Communication Networks (S-Pcns), Khudeja Khan Jan 2008

Data Communication With A Nano-Satellite Using Satellite Personal Communication Networks (S-Pcns), Khudeja Khan

Electronic Theses and Dissertations

Satellites typically communicate with locations on the ground to receive commands and send data back. Establishing reliable communications generally requires dedicated ground stations, which in turn require hardware and expertise. Developers of nano-satellites, however, may not have the expertise or resources necessary for establishing a dedicated ground station. Therefore, the use of an existing communication system, such as the Satellite Personal Communication Networks (S-PCNs), is attractive. Another shortcoming of the fixed ground stations, already available, is that they are normally only able to communicate with Low Earth Orbit (LEO) nano-satellites four times per day (two10-minute windows separated by 90 minutes, …

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Vcluster: A Portable Virtual Computing Library For Cluster Computing, Hua Zhang Jan 2008

Vcluster: A Portable Virtual Computing Library For Cluster Computing, Hua Zhang

Electronic Theses and Dissertations

Message passing has been the dominant parallel programming model in cluster computing, and libraries like Message Passing Interface (MPI) and Portable Virtual Machine (PVM) have proven their novelty and efficiency through numerous applications in diverse areas. However, as clusters of Symmetric Multi-Processor (SMP) and heterogeneous machines become popular, conventional message passing models must be adapted accordingly to support this new kind of clusters efficiently. In addition, Java programming language, with its features like object oriented architecture, platform independent bytecode, and native support for multithreading, makes it an alternative language for cluster computing. This research presents a new parallel programming model …

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Impact Of Construction On Freeway Traffic Operations, Seema Jagtap Jan 2008

Impact Of Construction On Freeway Traffic Operations, Seema Jagtap

Electronic Theses and Dissertations

This study provides an insight into the impact of construction activities on traffic operations. Specifically, the topic of interest for this thesis is to study the impact of construction on traffic operations for construction projects on Interstate 4 from SR 434 to John Young Parkway, from SR 528 to SR 535, and from SR 482 to SR 528. These three projects were chosen because they were the only projects on Interstate 4 where both construction data and loop detector data were available for analysis. The data was collected by examining the Florida Department of Transportation daily inspection reports which had …

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A Multi-Objective No-Regret Decision Making Model With Bayesian Learning For Autonomous Unmanned Systems, Matthew Howard Jan 2008

A Multi-Objective No-Regret Decision Making Model With Bayesian Learning For Autonomous Unmanned Systems, Matthew Howard

Electronic Theses and Dissertations

The development of a multi-objective decision making and learning model for the use in unmanned systems is the focus of this project. Starting with traditional game theory and psychological learning theories developed in the past, a new model for machine learning is developed. This model incorporates a no-regret decision making model with a Bayesian learning process which has the ability to adapt to errors found in preconceived costs associated with each objective. This learning ability is what sets this model apart from many others. By creating a model based on previously developed human learning models, hundreds of years of experience …

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Novel Complex Adaptive Signal Processing Techniques Employing Optimally Derived Time-Varying Convergence Factors With Applicatio, Raghuram Ranganathan Jan 2008

Novel Complex Adaptive Signal Processing Techniques Employing Optimally Derived Time-Varying Convergence Factors With Applicatio, Raghuram Ranganathan

Electronic Theses and Dissertations

In digital signal processing in general, and wireless communications in particular, the increased usage of complex signal representations, and spectrally efficient complex modulation schemes such as QPSK and QAM has necessitated the need for efficient and fast-converging complex digital signal processing techniques. In this research, novel complex adaptive digital signal processing techniques are presented, which derive optimal convergence factors or step sizes for adjusting the adaptive system coefficients at each iteration. In addition, the real and imaginary components of the complex signal and complex adaptive filter coefficients are treated as separate entities, and are independently updated. As a result, the …

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Development Of Hydraulic And Soil Properties For Soil Amendments And Native Soils For Retention Ponds In Marion County, Florida, Lisa Naujock Jan 2008

Development Of Hydraulic And Soil Properties For Soil Amendments And Native Soils For Retention Ponds In Marion County, Florida, Lisa Naujock

Electronic Theses and Dissertations

The vadose zone plays an important role in managing stormwater. Predicting the water balance and water movement is crucial in ground water remediation to keep water suitable for use. To aid in understanding soils ability to transmit and store water, soil and hydraulic properties were analyzed for soils in Marion County, Florida, and potential soil amendments. Soil and hydraulic properties were examined for two soil amendments and for the soils in Marion County, Florida, at the South Oak and the Hunter's Trace locations. The hydraulic properties measured were the soil moisture retention curve (SMRC) and saturated hydraulic conductivity (Ks). The …

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A Low Phase Noise K-Band Oscillator Utilizing An Embedded Dielectric Resonator On Multilayer High Frequency Laminates, Ajay Subramanian Jan 2008

A Low Phase Noise K-Band Oscillator Utilizing An Embedded Dielectric Resonator On Multilayer High Frequency Laminates, Ajay Subramanian

Electronic Theses and Dissertations

K-Band (18 to 26 GHz) dielectric resonator oscillators are typically used as a local oscillator in most K-Band digital transmitter/receiver topologies. Traditionally, the oscillator itself is made up of an active device, a dielectric resonator termination network, and a passive load matching network. The termination network embodies a cylindrical high permittivity dielectric resonator that is coupled on the same plane as a current carrying transmission line. This configuration provides an adequate resonance needed for oscillation but has some limitations. In order to provide a high Q resonance the entire oscillator is placed in a metal box to prevent radiation losses. …

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Reducing Effluent Phosphorus And Nitrogen Concentrations From A Stormwater Detention Pond Using A Chamber Upflow Filter And Skim, Patrick Ryan Jan 2008

Reducing Effluent Phosphorus And Nitrogen Concentrations From A Stormwater Detention Pond Using A Chamber Upflow Filter And Skim, Patrick Ryan

Electronic Theses and Dissertations

Stormwater runoff is a known pollutant source capable of causing surface water degradation, especially in highly populated areas such as Central Florida. Wet detention ponds manage this stormwater, but most of the ponds do not remove enough nutrients, specifically nitrogen and phosphorus, to meet TMDL regulations. This research provides a possible addition to a detention pond in Seminole County, Florida using a Chamber Upflow Filter and Skimmer (CUFS), which can increase the removal of phosphorus and nitrogen by the system. Water enters the system through the skimmer, which floats on the surface of the detention pond. It travels from the …

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