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Mathematical Modeling Of Infectious Diseases With Latency: Homogeneous Mixing And Contact Network, Keith Carlson Jan 2016

Mathematical Modeling Of Infectious Diseases With Latency: Homogeneous Mixing And Contact Network, Keith Carlson

Electronic Theses and Dissertations

In mathematical epidemiology, the standard compartmental models assume homogeneous mixing in the host population, in contrast to the disease spread process over a real host contact network. One approach to incorporating heterogeneous mixing is to consider the population to be a network of individuals whose contacts follow a given probability distribution. In this thesis we investigate in analogy both homogeneous mixing and contact network models for infectious diseases that admit latency periods, such as dengue fever, Ebola, and HIV. We consider the mathematics of the compartmental model as well as the network model, including the dynamics of their equations from …

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Multi-Purpose Device For Analyzing And Measuring Ultra-Short Pulses, Naman Anilkumar Mehta Jan 2016

Multi-Purpose Device For Analyzing And Measuring Ultra-Short Pulses, Naman Anilkumar Mehta

Electronic Theses and Dissertations

Intensity auto correlator is device to measure pulse widths of ultrashort pulses on the order of picoseconds and femtoseconds. I have built an in-house, compact, portable, industry standard intensity auto correlator for measuring ultrashort pulse-widths. My device is suitable for pulse-widths from 500 ps to 50 fs. The impetus for developing this instrument stemmed from our development of a multicore-fiber laser for high power laser applications, which also produces very short pulses that cannot be measured with an oscilloscope. As techniques for measuring short pulse-widths have been well studied, what made my journey exciting was the process of taking an …

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Verification And Automated Synthesis Of Memristor Crossbars, Arya Pourtabatabaie Jan 2016

Verification And Automated Synthesis Of Memristor Crossbars, Arya Pourtabatabaie

Electronic Theses and Dissertations

The Memristor is a newly synthesized circuit element correlating differences in electrical charge and magnetic flux, which effectively acts as a nonlinear resistor with memory. The small size of this element and its potential for passive state preservation has opened great opportunities for data-level parallel computation, since the functions of memory and processing can be realized on the same physical device. In this research we present an in-depth study of memristor crossbars for combinational and sequential logic. We outline the structure of formulas which they are able to produce and henceforth the inherent powers and limitations of Memristive Crossbar Computing. …

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Impact Of Wireless Channel Uncertainty Upon M-Ary Distributed Detection Systems., Zahra Hajibabaei Najafabadi Jan 2016

Impact Of Wireless Channel Uncertainty Upon M-Ary Distributed Detection Systems., Zahra Hajibabaei Najafabadi

Electronic Theses and Dissertations

We consider a wireless sensor network (WSN), consisting of several sensors and a fusion center (FC), which is tasked with solving an $M$-ary hypothesis testing problem. Sensors make $M$-ary decisions and transmit their digitally modulated decisions over orthogonal channels, which are subject to Rayleigh fading and noise, to the FC. Adopting Bayesian optimality criterion, we consider training and non-training based distributed detection systems and investigate the effect of imperfect channel state information (CSI) on the optimal maximum a posteriori probability (MAP) fusion rules and detection performance, when the sum of training and data symbol transmit powers is fixed. Our results …

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Techniques For Automated Parameter Estimation In Computational Models Of Probabilistic Systems, Faraz Hussain Jan 2016

Techniques For Automated Parameter Estimation In Computational Models Of Probabilistic Systems, Faraz Hussain

Electronic Theses and Dissertations

The main contribution of this dissertation is the design of two new algorithms for automatically synthesizing values of numerical parameters of computational models of complex stochastic systems such that the resultant model meets user-specified behavioral specifications. These algorithms are designed to operate on probabilistic systems – systems that, in general, behave differently under identical conditions. The algorithms work using an approach that combines formal verification and mathematical optimization to explore a model's parameter space. The problem of determining whether a model instantiated with a given set of parameter values satisfies the desired specification is first defined using formal verification terminology, …

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Transcriptional And Post-Transcriptional Regulation Of Gene Expression, Jun Ding Jan 2016

Transcriptional And Post-Transcriptional Regulation Of Gene Expression, Jun Ding

Electronic Theses and Dissertations

Regulation of gene expression includes a variety of mechanisms to increase or decrease specific gene products. Gene expression can be regulated at any stage from transcription to post-transcription and it's essential to almost all living organisms, as it increases the versatility and adaptability by allowing the cell to express the needed proteins. In this dissertation, we comprehensively studied the gene regulation from both transcriptional and post-transcriptional points of view. Transcriptional regulation is by which cells regulate the transcription from DNA to RNA, thereby directing gene activity. Transcriptional factors (TFs) play a very important role in transcriptional regulation and they are …

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High Temperature Shock Tube Ignition Studies Of Co2 Diluted Mixtures, Owen Pryor Jan 2016

High Temperature Shock Tube Ignition Studies Of Co2 Diluted Mixtures, Owen Pryor

Electronic Theses and Dissertations

Energy demand is expected to grow by 20% over the next 10 years. In order to account for this increase in energy consumption new and novel combustion techniques are required to mitigate the effects of pollution and fossil fuel dependency. Oxy-fuel combustion in supercritical carbon dioxide (sCO2) cycles can increase plant efficiencies up to 52% and reduce pollutants such as NOX and CO2 by 99%. Supercritical engine cycles have demonstrated electricity costs of $121/MWh, which is competitive in comparison to conventional coal ($95.60/MWh) and natural gas power plants ($128.4/MWe). This increase in efficiency is mainly driven by the near-liquid density …

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Analysis Of Commutativity With State-Chart Graph Representation Of Concurrent Programs., Kishore Debnath Jan 2016

Analysis Of Commutativity With State-Chart Graph Representation Of Concurrent Programs., Kishore Debnath

Electronic Theses and Dissertations

We present a new approach to check for Commutativity in concurrent programs from their run-time state-chart graphs. Two operations are said to be commutative if changing the order of their execution do not change the resultant effect on the working object. Commutative property is capable of boosting performance in concurrent transactions such that transactional concurrency is comparable to a non-blocking linearizable version of a similar data structure type. Transactional concurrency is a technique that analyses object semantics, as object states, to determine conflicts and recovery between conflicting operations. Processes that commute at object level can be executed concurrently at transaction …

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Improving Efficiency In Deep Learning For Large Scale Visual Recognition, Baoyuan Liu Jan 2016

Improving Efficiency In Deep Learning For Large Scale Visual Recognition, Baoyuan Liu

Electronic Theses and Dissertations

The emerging recent large scale visual recognition methods, and in particular the deep Convolutional Neural Networks (CNN), are promising to revolutionize many computer vision based artificial intelligent applications, such as autonomous driving and online image retrieval systems. One of the main challenges in large scale visual recognition is the complexity of the corresponding algorithms. This is further exacerbated by the fact that in most real-world scenarios they need to run in real time and on platforms that have limited computational resources. This dissertation focuses on improving the efficiency of such large scale visual recognition algorithms from several perspectives. First, to …

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Characterization Of Slm-Manufactured Turbine Blade Microfeatures From Superalloy Powders, Brandon Ealy Jan 2016

Characterization Of Slm-Manufactured Turbine Blade Microfeatures From Superalloy Powders, Brandon Ealy

Electronic Theses and Dissertations

The limits of gas turbine technology are heavily influenced by materials and manufacturing capabilities. Inconel remains the material of choice for most hot gas path (HGP) components in gas turbines, however recent increases in turbine inlet temperature (TIT) are associated with the development of advanced convective cooling methods and ceramic thermal barrier coatings. Increasing cycle efficiency and cycle specific work are the primary drivers for increasing TIT. Lately, incremental performance gains responsible for increasing the allowable TIT have been made mainly through innovations in cooling technology, specifically convective cooling schemes. An emerging manufacturing technology may further facilitate the increase of …

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Live Versus Virtual: Cost Benefit Analysis For Applying Simulation Towards Army Aviator Flight Minimums, Dylan Morelle Jan 2016

Live Versus Virtual: Cost Benefit Analysis For Applying Simulation Towards Army Aviator Flight Minimums, Dylan Morelle

Electronic Theses and Dissertations

The Longbow Crew Trainer (LCT) is a cost effective, safe alternative to live training in the AH-64D/E Apache helicopter. Current Army doctrine and regulations have provisions for the limited use of simulator in lieu of aircraft hours toward semiannual minimum flight hour requirements. With the defense budget in decline, the Army must find innovative, cost effective methods to conduct realistic, relevant training to sustain proficiency in their warfighting capabilities. The LCT fully replicates the cockpit environment through training scenarios for requisite crew tasks and missions in a realistic, modular, and transportable solution. An attack helicopter crew can safely train in …

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Biophysical Sources Of 1/F Noises In Neurological Tissue, Alan Paris Jan 2016

Biophysical Sources Of 1/F Noises In Neurological Tissue, Alan Paris

Electronic Theses and Dissertations

High levels of random noise are a defining characteristic of neurological signals at all levels, from individual neurons up to electroencephalograms (EEG). These random signals degrade the performance of many methods of neuroengineering and medical neuroscience. Understanding this noise also is essential for applications such as real-time brain-computer interfaces (BCIs), which must make accurate control decisions from very short data epochs. The major type of neurological noise is of the so-called 1/f-type, whose origins and statistical nature has remained unexplained for decades. This research provides the first simple explanation of 1/f-type neurological noise based on biophysical fundamentals. In addition, noise …

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Catalytically Enhanced Heterogeneous Combustion Of Methane, Anthony Terracciano Jan 2016

Catalytically Enhanced Heterogeneous Combustion Of Methane, Anthony Terracciano

Electronic Theses and Dissertations

Heterogeneous combustion is an advanced internal combustion technique, which enables heat recuperation within the flame by utilizing a highly porous ceramic media as a regenerator. Heat released within the gas phase convectively transfers to the solid media. This heat within the solid media then travels towards the inlet, enabling reactant preheating. Such heat redistribution enables stable burning of both ultra-lean fuel/air mixtures, forming a more diffuse flame through the combustion chamber, and results in reduced pollutant formation. To further enhance heterogeneous combustion, the ceramic media can be coated with catalytically active materials, which facilitates surface based chemical reactions that could …

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Determining The Feasibility Of Using Micro Simulation To Asses Safety Of Pedestrian Crossings, Jenner Darius Jan 2016

Determining The Feasibility Of Using Micro Simulation To Asses Safety Of Pedestrian Crossings, Jenner Darius

Electronic Theses and Dissertations

For the past several decades, pedestrian safety has been an oncoming issue that has thrown the area of transportation engineering into a frenzy. Pedestrian safety has become predominantly one of the leading causes of fatalities in traffic accidents. Florida has been reported as one of the leading states in pedestrian fatalities with 2.56 fatality rate per 100,000 population and about 20 percent of all traffic fatalities in the state of Florida. Nonetheless, as research is being done and hypotheses are being calibrated and produced, there has to be a way of measuring and determining the number of pedestrian-to-vehicle conflicts without …

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Confluence Of Vision And Natural Language Processing For Cross-Media Semantic Relations Extraction, Amara Tariq Jan 2016

Confluence Of Vision And Natural Language Processing For Cross-Media Semantic Relations Extraction, Amara Tariq

Electronic Theses and Dissertations

In this dissertation, we focus on extracting and understanding semantically meaningful relationships between data items of various modalities; especially relations between images and natural language. We explore the ideas and techniques to integrate such cross-media semantic relations for machine understanding of large heterogeneous datasets, made available through the expansion of the World Wide Web. The datasets collected from social media websites, news media outlets and blogging platforms usually contain multiple modalities of data. Intelligent systems are needed to automatically make sense out of these datasets and present them in such a way that humans can find the relevant pieces of …

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Data-Driven Predictive Analytics For Distributed Smart Grid Control, Hamed Valizadehhaghi Jan 2016

Data-Driven Predictive Analytics For Distributed Smart Grid Control, Hamed Valizadehhaghi

Electronic Theses and Dissertations

The smart grid is expected to support an interconnected network of self-contained microgrids. Nonetheless, the distributed integration of renewable generation and demand response adds complexity to the control and optimization of smart grid. Forecasts are essential due to the existence of stochastic variations and uncertainty. Forecasting data are spatio-temporal which means that the data correspond to regular intervals, say every hour, and the analysis has to take account of spatial dependence among the distributed generators or locations. Hence, smart grid operations must take account of, and in fact benefit from the temporal dependence as well as the spatial dependence. This …

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Aeroelastic Investigation Of A Circumferentially Varying Tip Gap In An Axial Compressor Rotor, Ornan David Canon Jan 2016

Aeroelastic Investigation Of A Circumferentially Varying Tip Gap In An Axial Compressor Rotor, Ornan David Canon

Electronic Theses and Dissertations

The tip leakage flow in axial compressors is a significant factor in engine performance and a subject of investigation over the last several decades. Many studies have already shown that the vortices generated by this tip leakage can have a negative impact on the surrounding flow field and overall performance, and could potentially lead to excitations as well. This study examines the effect of these vortices on aeroelasticity. Specifically, it looks at the effect from a circumferentially varying tip gap, such as that produced by casing ovalization. For this project, the casing ovalization of an industrial gas turbine compressor was …

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Content-Based Information Retrieval Via Nearest Neighbor Search, Yinjie Huang Jan 2016

Content-Based Information Retrieval Via Nearest Neighbor Search, Yinjie Huang

Electronic Theses and Dissertations

Content-based information retrieval (CBIR) has attracted significant interest in the past few years. When given a search query, the search engine will compare the query with all the stored information in the database through nearest neighbor search. Finally, the system will return the most similar items. We contribute to the CBIR research the following: firstly, Distance Metric Learning (DML) is studied to improve retrieval accuracy of nearest neighbor search. Additionally, Hash Function Learning (HFL) is considered to accelerate the retrieval process. On one hand, a new local metric learning framework is proposed - Reduced-Rank Local Metric Learning (R2LML). By considering …

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A Study Of Holistic Strategies For The Recognition Of Characters In Natural Scene Images, Muhammad Ali Jan 2016

A Study Of Holistic Strategies For The Recognition Of Characters In Natural Scene Images, Muhammad Ali

Electronic Theses and Dissertations

Recognition and understanding of text in scene images is an important and challenging task. The importance can be seen in the context of tasks such as assisted navigation for the blind, providing directions to driverless cars, e.g. Google car, etc. Other applications include automated document archival services, mining text from images, and so on. The challenge comes from a variety of factors, like variable typefaces, uncontrolled imaging conditions, and various sources of noise corrupting the captured images. In this work, we study and address the fundamental problem of recognition of characters extracted from natural scene images, and contribute three holistic …

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Enhanced Hardware Security Using Charge-Based Emerging Device Technology, Yu Bi Jan 2016

Enhanced Hardware Security Using Charge-Based Emerging Device Technology, Yu Bi

Electronic Theses and Dissertations

The emergence of hardware Trojans has largely reshaped the traditional view that the hardware layer can be blindly trusted. Hardware Trojans, which are often in the form of maliciously inserted circuitry, may impact the original design by data leakage or circuit malfunction. Hardware counterfeiting and IP piracy are another two serious issues costing the US economy more than $200 billion annually. A large amount of research and experimentation has been carried out on the design of these primitives based on the currently prevailing CMOS technology. However, the security provided by these primitives comes at the cost of large overheads mostly …

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Developing New Power Management And High-Reliability Schemes In Data-Intensive Environment, Ruijun Wang Jan 2016

Developing New Power Management And High-Reliability Schemes In Data-Intensive Environment, Ruijun Wang

Electronic Theses and Dissertations

With the increasing popularity of data-intensive applications as well as the large-scale computing and storage systems, current data centers and supercomputers are often dealing with extremely large data-sets. To store and process this huge amount of data reliably and energy-efficiently, three major challenges should be taken into consideration for the system designers. Firstly, power conservation–Multicore processors or CMPs have become a mainstream in the current processor market because of the tremendous improvement in transistor density and the advancement in semiconductor technology. However, the increasing number of transistors on a single die or chip reveals a super-linear growth in power consumption …

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Modeling And Solving Large-Scale Stochastic Mixed-Integer Problems In Transportation And Power Systems, Zhouchun Huang Jan 2016

Modeling And Solving Large-Scale Stochastic Mixed-Integer Problems In Transportation And Power Systems, Zhouchun Huang

Electronic Theses and Dissertations

In this dissertation, various optimization problems from the area of transportation and power systems will be respectively investigated and the uncertainty will be considered in each problem. Specifically, a long-term problem of electricity infrastructure investment is studied to address the planning for capacity expansion in electrical power systems with the integration of short-term operations. The future investment costs and real-time customer demands cannot be perfectly forecasted and thus are considered to be random. Another maintenance scheduling problem is studied for power systems, particularly for natural gas fueled power plants, taking into account gas contracting and the opportunity of purchasing and …

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The Effect Of Vibrations On Cryogens Boil Off During Launch, Transfer And Transport, Erin Schlichenmaier Jan 2016

The Effect Of Vibrations On Cryogens Boil Off During Launch, Transfer And Transport, Erin Schlichenmaier

Electronic Theses and Dissertations

Boil-off of a cryogenic fluid which is caused by the temperature difference between the fluid and its environment is a phenomenon which has long been studied and is well understood. However, vibrational excitation of a cryogenic storage tank and the fluid inside it also play a role in the loss of cryogens. Mechanical energy applied to the system in the form of vibrational input is converted into thermal energy via viscous damping of the fluid. As a result, when a storage tank full of cryogenic fluids is vibrated, it boils off at an increased rate. A series of experiments were …

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Assessing The Effect Of Social Networks On Employee Creativity In A Fast-Food Restaurant Environment, Mitchell Rabinowitz Jan 2016

Assessing The Effect Of Social Networks On Employee Creativity In A Fast-Food Restaurant Environment, Mitchell Rabinowitz

Electronic Theses and Dissertations

Creativity has been widely recognized as critical to the economic success of organizations for over 60 years. Today, it is considered to be the most highly prized "commodity" of businesses. As such, there have been numerous efforts to better understand creativity with the goal of increasing individual creativity and therefore improving the economic success of organizations. An emerging area of research on creativity recognizes creativity as a complex, social process that is dependent upon many factors, including those of an environmental nature. In support of this perspective, a growing amount of research has investigated the effect of social networks on …

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Modeling Mass Transfer And Assessing Cost And Performance Of A Hollow Fiber Nanofiltration Membrane Process, David Yonge Jan 2016

Modeling Mass Transfer And Assessing Cost And Performance Of A Hollow Fiber Nanofiltration Membrane Process, David Yonge

Electronic Theses and Dissertations

Bench-scale water treatment testing of three next generation hollow-fiber (HF) nanofiltration (NF) membranes was conducted to characterize divalent ion rejection capabilities and investigate removal mechanisms. Existing mathematical models were investigated to describe solute transport using synthetic magnesium sulfate solutions including the size exclusion model, homogenous solution diffusion (HSD) model, dimensional analysis, and the HSD model incorporating film theory. Solute transport for two of the membranes were described by HSD theory and were predictive of their 90% divalent ion removal. A third membrane was more accurately modeled using size exclusion and was found to be predictive of its 40% divalent ion …

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Investigation Of The Effect Of Rain On Sea Surface Salinity, Andrea Santos Garcia Jan 2016

Investigation Of The Effect Of Rain On Sea Surface Salinity, Andrea Santos Garcia

Electronic Theses and Dissertations

The Aquarius/SAC-D mission provided Sea Surface Salinity (SSS), globally over the ocean, for almost 4 years. As a member of the AQ/SAC-D Cal/Val team, the Central Florida Remote Sensing Laboratory has analyzed these salinity measurements in the presence of precipitation and has noted the high correlation between the spatial patterns of reduced SSS and the spatial distribution of rain. It was determined that this is the result of a cause and effect relation, and not SSS measurement errors. Thus, it is important to understand these salinity changes due to seawater dilution by rain and the associated near-surface salinity strati?cation. This …

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The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2016, Buenaventura "Ven" Basco Jan 2016

The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2016, Buenaventura "Ven" Basco

Libraries' Newsletters

No abstract provided.

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Can Best Practices In Writing Instruction And Standardized Testing Coexist?, Karen Cannavino Jan 2016

Can Best Practices In Writing Instruction And Standardized Testing Coexist?, Karen Cannavino

Electronic Theses and Dissertations

At the high school level, teachers are tasked with a twofold agenda: they must prepare their students for college level and other post-secondary writing, and they must also make sure they perform well on the standardized writing tests that are required by the state. The stakes in standardized testing continue to rise, especially in Florida. Since the passing of the No Child Left Behind Act in 2002 (NCLB) and the implementation of the Race to the Top Assessment Program (RTTT) in 2009, teachers across the nation have experienced intense pressures related to standardized testing. Many schools' efforts to conform to …

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The Owl Sensor: A Smart Nanostructure For Single Nucleotide Variation Analysis, Rebekah Karadeema Jan 2016

The Owl Sensor: A Smart Nanostructure For Single Nucleotide Variation Analysis, Rebekah Karadeema

Electronic Theses and Dissertations

Analysis of single nucleotide variations (SNVs) in DNA and RNA sequences is extensively used in healthcare for detection of genetic mutations and analysis of drug resistant pathogens. Here we developed a nucleic acid sensor able to differentiate between a fully matched analyte and one with a SNV in a wide temperature range of 5°C-32°C. The sensor, dubbed here the 'Owl Sensor' due to the complex's resemblance to owl eyes, utilizes recent developments in DNA nanotechnology and synthetic biology to self-assemble a fluorescent DNA nanostructure called a Double Crossover, or DX Tile, capable of differentiating SNVs in a large temperature range, …

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A Framework For Transforming Elementary Literacy Coaches' Professional Learning, Lenora Forsythe Jan 2016

A Framework For Transforming Elementary Literacy Coaches' Professional Learning, Lenora Forsythe

Electronic Theses and Dissertations

Elementary literacy coaches serve as one component in a professional learning system to support teacher learning. This dissertation in practice intended to highlight the need for an effective professional learning system for elementary literacy coaches that will enable them to impact teacher and student learning. The pilot study explored needs and perspectives of professional learning opportunities for elementary literacy coaches in a central Florida school district. Findings from the pilot study, along with literature surrounding the topic, resulted in the design of A Framework for Elementary Literacy Coaches' Professional Learning. This Framework utilized components from existing resources to develop access …

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