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Blockchain-Driven Secure And Transparent Audit Logs, Ashar Ahmad Jan 2019

Blockchain-Driven Secure And Transparent Audit Logs, Ashar Ahmad

Electronic Theses and Dissertations

In enterprise business applications, large volumes of data are generated daily, encoding business logic and transactions. Those applications are governed by various compliance requirements, making it essential to provide audit logs to store, track, and attribute data changes. In traditional audit log systems, logs are collected and stored in a centralized medium, making them prone to various forms of attacks and manipulations, including physical access and remote vulnerability exploitation attacks, and eventually allowing for unauthorized data modification, threatening the guarantees of audit logs. Moreover, such systems, and given their centralized nature, are characterized by a single point of failure. To …

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Scalable Network Design And Management With Decentralized Software-Defined Networking, Kuldip Singh Atwal Jan 2019

Scalable Network Design And Management With Decentralized Software-Defined Networking, Kuldip Singh Atwal

Electronic Theses and Dissertations

Network softwarization is among the most significant innovations of computer networks in the last few decades. The lack of uniform and programmable interfaces for network management led to the design of OpenFlow protocol for the university campuses and enterprise networks. This breakthrough coupled with other similar efforts led to an emergence of two complementary but independent paradigms called software-defined networking (SDN) and network function virtualization (NFV). As of this writing, these paradigms are becoming the de-facto norms of wired and wireless networks alike. This dissertation mainly addresses the scalability aspect of SDN for multiple network types. Although centralized control and …

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Design Of Unimorph Out-Of-Plane Piezoelectric Actuator, Kevin Chan Jan 2019

Design Of Unimorph Out-Of-Plane Piezoelectric Actuator, Kevin Chan

Electronic Theses and Dissertations

Electromechanical transduction is an important component of microelectromechanical systems (MEMS), a technology with wide-ranging applications, including mobile computing, sensors, energy harvesting, and displays. These disparate applications have varying performance requirements, but generally transduction efficiency, mechanical precision, response time, cost, compatibility with photolithography and other fabrication processes, and operability at micro-scale are all desired metrics for MEMS devices. Piezoelectric transduction provides substantial advantages, including precise displacements, quick response times, and high transduction efficiency. These strengths make piezoelectric transduction particularly well-suited for use in resonators, sensors, and energy harvesters. However, piezoelectric transduction also produces much smaller magnitudes of movements than other electromechanical …

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Dynamics Of A Perfectly Premixed Jet Flame Exhibiting Self-Excited High-Frequency, Transverse Thermoacoustic Instabilities, Lucky Tran Jan 2019

Dynamics Of A Perfectly Premixed Jet Flame Exhibiting Self-Excited High-Frequency, Transverse Thermoacoustic Instabilities, Lucky Tran

Electronic Theses and Dissertations

This work is an investigation of the behavior of a premixed turbulent jet flame in a cylindrical dump combustor. The degeneracy of the simple configuration in this study lends itself for a detailed study of inherent mechanisms of a self-excited thermoacoustic instability in isolation from system coupling effects, enabling detailed numerical simulations to be carried out to supplement experimental findings. Tests were done at a nominal pressure of 8 bar and inlet temperature around 450 ˚C. Self-excited large eddy simulations were also carried out in OpenFOAM, using a b-Ξ flame-wrinkling model to model the combustion process. Eigenfrequency analysis in COMSOL …

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Adsorption Capacity Assessment Of Advance Green Environmental Media To Remove Nutrients From Stormwater-Runoff, Hanan Elhakiem Jan 2019

Adsorption Capacity Assessment Of Advance Green Environmental Media To Remove Nutrients From Stormwater-Runoff, Hanan Elhakiem

Electronic Theses and Dissertations

Best Management Practices (BMPs) in stormwater treatment are a suite of treatment alternatives to deal with pollutant removal problems from stormwater runoff. Biosorption-activated media (BAM) are green sorption media consists of recycled materials have shown excellent nutrient removal as an effective BMP by enhancing physicochemical and microbiological processes. In this study, Iron-Filling Green Environmental Media (denoted as IFGEM-3) and Advanced Green Environmental Media 1 and 2 (denoted as AGEM-1 and AGEM-2) were produced and tested for their adsorption capacities as well as removal and recovery potential for phosphate, nitrate, and ammonia against natural soil (baseline) collected from a stormwater retention …

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Simulation Analysis Of A Ventilated Building Integrated Photovoltaic Air-Gap Duct System For Natural Ventilation Of A Building, Arash Zarmehr Jan 2019

Simulation Analysis Of A Ventilated Building Integrated Photovoltaic Air-Gap Duct System For Natural Ventilation Of A Building, Arash Zarmehr

Electronic Theses and Dissertations

We introduce a low-cost and low-maintenance wind-catcher duct system design addition to BIPV systems that increase airflow velocity and decrease air temperature resulting in increased performance for the PV system electricity output. The results of our work demonstrate the design can further enhance energy performance by utilizing the increased airflow from the duct system to naturally ventilate an attic. Similar benefits were observed for different variations of the design under a parametric analysis finding the most optimal configuration to increase airflow velocity and decrease temperature. Building integrated photovoltaics (BIPV) is becoming more popular and widely used to increase sustainability and …

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Multiphase Flow Modeling Of Molten Metal Atomization At High Gas Pressure, Kalpana Hanthanan Arachchilage Jan 2019

Multiphase Flow Modeling Of Molten Metal Atomization At High Gas Pressure, Kalpana Hanthanan Arachchilage

Electronic Theses and Dissertations

The high-pressure gas atomization is well known as one of the best powder manufacturing processes due to its controllability over powder size distribution. However, with the continuous improvement of new alloys, optimizing the operating parameters to maximize the yield is costly and time-consuming. Therefore, it is essential to understand the high-pressure gas atomization process and the effects of different operational parameters on the powder size distribution. Two-phase numerical simulations are performed to capture the interfacial dynamic during the atomization process and to obtain the effects of gas pressure, melt flow rate, and thermophysical properties of atomizing gas and the molten …

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A Framework To Develop Anomaly Detection/Fault Isolation Architecture Using System Engineering Principles, Thomas Clark Jan 2019

A Framework To Develop Anomaly Detection/Fault Isolation Architecture Using System Engineering Principles, Thomas Clark

Electronic Theses and Dissertations

For critical systems, timely recognition of an anomalous condition immediately starts the evaluation process. For complex systems, isolating the fault to a component or subsystem results in corrective action sooner so that undesired consequences may be minimized. There are many unique anomaly detection and fault isolation capabilities available with innovative techniques to quickly discover an issue and identify the underlying problems. This research develops a framework to aid in the selection of appropriate anomaly detection and fault isolation technology to augment a given system. To optimize this process, the framework employs a model based systems engineering approach. Specifically, a SysML …

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Autonomous Robotic Grasping In Unstructured Environments, Amirhossein Jabalameli Jan 2019

Autonomous Robotic Grasping In Unstructured Environments, Amirhossein Jabalameli

Electronic Theses and Dissertations

A crucial problem in robotics is interacting with known or novel objects in unstructured environments. While the convergence of a multitude of research advances is required to address this problem, our goal is to describe a framework that employs the robot's visual perception to identify and execute an appropriate grasp to pick and place novel objects. Analytical approaches explore for solutions through kinematic and dynamic formulations. On the other hand, data-driven methods retrieve grasps according to their prior knowledge of either the target object, human experience, or through information obtained from acquired data. In this dissertation, we propose a framework …

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Supporting Learning In 3d Virtual Environments: The Impact Of Intergenerational Joint Media Engagement, Robert Michlowitz Jan 2019

Supporting Learning In 3d Virtual Environments: The Impact Of Intergenerational Joint Media Engagement, Robert Michlowitz

Electronic Theses and Dissertations

Studies have indicated that intergenerational relationships can assist children to learn more efficiently by providing support. As new forms of media have emerged and become pervasive in our society, it is important to understand how children use them to learn. Just as television coviewing has been observed by past researchers to aid youths to learn with parents and grandparents, three-dimensional virtual learning environments (VLE) are being investigated for their potential. This study seeks to examine the potential learning impact on children, ages 8 to 13, encountering a three-dimensional virtual learning environment with their grandparents. The primary research question this study …

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Modeling And Transient Simulation Of A Fully Integrated Multi-Pressure Heat Recovery Steam Generator Using Siemens T3000, Jonathan Mcconnell Jan 2019

Modeling And Transient Simulation Of A Fully Integrated Multi-Pressure Heat Recovery Steam Generator Using Siemens T3000, Jonathan Mcconnell

Electronic Theses and Dissertations

The focus of this research is on the transient thermodynamic properties and dynamic behavior of a Heat Recovery Steam Generator (HRSG). An HRSG is a crossflow heat exchanger designed for the extraction of energy from the hot exhaust gas of a traditional power plant through boiling induced phase change. Superheated steam is sent through a turbine to generate additional power, raising the overall efficiency of a power plant. The addition of renewable energies and the evolution of smart grids have brought forth a necessity to gain a comprehensive understanding of transient behavior within an HRSG in order to efficiently manage …

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Action Recognition, Temporal Localization And Detection In Trimmed And Untrimmed Video, Rui Hou Jan 2019

Action Recognition, Temporal Localization And Detection In Trimmed And Untrimmed Video, Rui Hou

Electronic Theses and Dissertations

Automatic understanding of videos is one of the most active areas of computer vision research. It has applications in video surveillance, human computer interaction, video sports analysis, virtual and augmented reality, video retrieval etc. In this dissertation, we address four important tasks in video understanding, namely action recognition, temporal action localization, spatial-temporal action detection and video object/action segmentation. This dissertation makes contributions to above tasks by proposing. First, for video action recognition, we propose a category level feature learning method. Our proposed method automatically identifies such pairs of categories using a criterion of mutual pairwise proximity in the (kernelized) feature …

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Sparse Signal Recovery Under Sensing And Physical Hardware Constraints, Davood Mardaninajafabadi Jan 2019

Sparse Signal Recovery Under Sensing And Physical Hardware Constraints, Davood Mardaninajafabadi

Electronic Theses and Dissertations

This dissertation focuses on information recovery under two general types of sensing constraints and hardware limitations that arise in practical data acquisition systems. We study the effects of these practical limitations in the context of signal recovery problems from interferometric measurements such as for optical mode analysis. The first constraint stems from the limited number of degrees of freedom of an information gathering system, which gives rise to highly constrained sensing structures. In contrast to prior work on compressive signal recovery which relies for the most part on introducing additional hardware components to emulate randomization, we establish performance guarantees for …

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Detecting Anomalies From Big Data System Logs, Siyang Lu Jan 2019

Detecting Anomalies From Big Data System Logs, Siyang Lu

Electronic Theses and Dissertations

Nowadays, big data systems (e.g., Hadoop and Spark) are being widely adopted by many domains for offering effective data solutions, such as manufacturing, healthcare, education, and media. A common problem about big data systems is called anomaly, e.g., a status deviated from normal execution, which decreases the performance of computation or kills running programs. It is becoming a necessity to detect anomalies and analyze their causes. An effective and economical approach is to analyze system logs. Big data systems produce numerous unstructured logs that contain buried valuable information. However manually detecting anomalies from system logs is a tedious and daunting …

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A Methodology For Data-Driven Decision-Making In Last Mile Delivery Operations, Edgar Gutierrez Franco Jan 2019

A Methodology For Data-Driven Decision-Making In Last Mile Delivery Operations, Edgar Gutierrez Franco

Electronic Theses and Dissertations

Across all industries, from manufacturing to services, decision-makers must deal day to day with the outcomes from past and current decisions that affect their business. Last-mile delivery is the term used in supply chain management to describe the movement of goods from a hub to final destinations. This research proposes a methodology that supports decision making for the execution of last-mile delivery operations in a supply chain. This methodology offers diverse, hybrid, and complementary techniques (e.g., optimization, simulation, machine learning, and geographic information systems) to understand last-mile delivery operations through data-driven decision-making. The hybrid modeling might create better warning systems …

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Saw Correlator Temperature Compensation Using A Pulse Width Modulated Temperature Controller, Daniel Betancourt Jan 2019

Saw Correlator Temperature Compensation Using A Pulse Width Modulated Temperature Controller, Daniel Betancourt

Electronic Theses and Dissertations

A Surface Acoustic Wave (SAW) correlator built on a Lithium Niobate substrate is temperature compensated in order to maintain a constant center frequency. Frequency shifts as a result of temperature variations limit device performance. An Arduino®-based PWM temperature controller is developed to read the device temperature from a resistance temperature detector located on the SAW wafer and to regulate its temperature to a specified setpoint by providing current to a heater which is co-located with the temperature sensor on the SAW correlator substrate. The final temperature controller achieves frequency shifts of 0.013 MHz from room temperature with a worst-case PPM …

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Multi-Touch Detection And Semantic Response On Non-Parametric Rear-Projection Surfaces, Jason Hochreiter Jan 2019

Multi-Touch Detection And Semantic Response On Non-Parametric Rear-Projection Surfaces, Jason Hochreiter

Electronic Theses and Dissertations

The ability of human beings to physically touch our surroundings has had a profound impact on our daily lives. Young children learn to explore their world by touch; likewise, many simulation and training applications benefit from natural touch interactivity. As a result, modern interfaces supporting touch input are ubiquitous. Typically, such interfaces are implemented on integrated touch-display surfaces with simple geometry that can be mathematically parameterized, such as planar surfaces and spheres; for more complicated non-parametric surfaces, such parameterizations are not available. In this dissertation, we introduce a method for generalizable optical multi-touch detection and semantic response on uninstrumented non-parametric …

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Evolutionary Model Discovery: Automating Causal Inference For Generative Models Of Human Social Behavior, Chathika Gunaratne Jan 2019

Evolutionary Model Discovery: Automating Causal Inference For Generative Models Of Human Social Behavior, Chathika Gunaratne

Electronic Theses and Dissertations

The desire to understand the causes of complex societal phenomena is fundamental to the social sciences. Society, at a macro-scale has many measurable characteristics in the form of statistical distributions and aggregate measures; data which is increasingly abundant with the proliferation of online social media, mobile devices, and the internet of things. However, the decision-making processes and limits of the individuals who interact to generate these statistical patterns are often difficult to unravel. Furthermore, multiple causal factors often interact to determine the outcome of a particular behavior. Quantifying the importance of these causal factors and their interactions, which make up …

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Investigation Of Computer Vision Concepts And Methods For Structural Health Monitoring And Identification Applications, Chuanzhi Dong Jan 2019

Investigation Of Computer Vision Concepts And Methods For Structural Health Monitoring And Identification Applications, Chuanzhi Dong

Electronic Theses and Dissertations

This study presents a comprehensive investigation of methods and technologies for developing a computer vision-based framework for Structural Health Monitoring (SHM) and Structural Identification (St-Id) for civil infrastructure systems, with particular emphasis on various types of bridges. SHM is implemented on various structures over the last two decades, yet, there are some issues such as considerable cost, field implementation time and excessive labor needs for the instrumentation of sensors, cable wiring work and possible interruptions during implementation. These issues make it only viable when major investments for SHM are warranted for decision making. For other cases, there needs to be …

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Experimental And Numerical Investigation Of A Novel Adsorption Bed Design For Cooling Applications, Ramy H. Mohammed Jan 2019

Experimental And Numerical Investigation Of A Novel Adsorption Bed Design For Cooling Applications, Ramy H. Mohammed

Electronic Theses and Dissertations

A global challenge is to develop environmentally friendly, affordable, compact and sustainable technologies to provide heating and cooling power. Adsorption cooling (AC) technology is one of the most promising ways to solve the environmental issues and cut down the energy consumption related to the traditional air conditioning and refrigeration systems. However, AC systems still suffer from poor heat and mass transfer inside the adsorption bed, which is the main obstacle to commercialization of adsorption cooling units. The main goal of this study is designing an efficient adsorption cooling cycle. In this research work, an in-depth scaling analysis of heat and …

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Broadband Mid-Infrared Frequency Combs Generated Via Frequency Division, Qitian Ru Jan 2019

Broadband Mid-Infrared Frequency Combs Generated Via Frequency Division, Qitian Ru

Electronic Theses and Dissertations

Frequency combs have revolutionized metrology and demonstrated numerous applications in science and technology. Combs operating in the mid-infrared region could be beneficial for molecular spectroscopy for several reasons. First, numerous molecules have their spectroscopic signatures in this region. Furthermore, the atmospheric window (3-5μm and 8-14μm) is located here. Additionally, a mid-infrared frequency comb could be employed as a diagnostic tool for the many components of human breath, as well as for detection of harmful gases and contaminants in the atmosphere. In this thesis, I used synchronously pumped subharmonic optical parametric oscillators (OPOs) operating at degeneracy to produce ultra-broadband outputs near …

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Artificial Magnetism And Topological Phenomena In Optics, Midya Parto Jan 2019

Artificial Magnetism And Topological Phenomena In Optics, Midya Parto

Electronic Theses and Dissertations

Recent years have witnessed intense research activities to effectively control the flow of photons using various classes of optical structures such as photonic crystals and metamaterials. In this regard, optics has benefited from concepts in condensed matter and solid-state physics, where similar problems concerning electronic wavefunctions arise. An important example of such correspondence is associated with the photon dynamics under the effect of an artificial magnetic field. This is especially important since photons, as neutral bosons, do not inherently interact with magnetic fields. One way to mitigate this issue is to exploit magneto-optical materials. However, as is well known, using …

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Borrowing Time: The Classical Tradition In The Poetic Thoeries Of T. S. Eliot And Ezra Pound, Nicholas Odom Jan 2019

Borrowing Time: The Classical Tradition In The Poetic Thoeries Of T. S. Eliot And Ezra Pound, Nicholas Odom

Honors Undergraduate Theses

T. S. Eliot and Ezra Pound are two of the most prominent figures of Anglo-American modernist poetry, both having played central roles in the development of a distinct poetic style and atmosphere in the early 20th century by means of their publishing and editing the work of other poets as well as publishing their own poetry. However, Eliot and Pound have an interest in the classical world that is not clearly shared with the majority of other modernist poets, and this interest distinguishes the sense of "modernism" that Eliot and Pound promoted from that of other major modernists like …

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A Narrative Research Study Of Self-Selected Tracking On Motivation In 10th Grade English Language Arts Classes, Audra Greuel Jan 2019

A Narrative Research Study Of Self-Selected Tracking On Motivation In 10th Grade English Language Arts Classes, Audra Greuel

Electronic Theses and Dissertations

The practice of tracking has had longstanding negative impacts on students, especially students in lower academic tracks. This research suggests that tracking develops the themes of a narrative of deficit through inequality and exclusion and impedes student motivation due to the negative implications. A common finding of outside research studies was that of disapproval for the current school organizational structure of tracking due to the negative consequences on students. Furthermore, several research studies developed an outline of positive ways to advocate for a unifying system of educational change. Educational leaders should heed the suggestions of researchers to promote changes within …

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Cultural Responsiveness And K-12 English Learners: Exploring Policy And Implementation Fidelity, Lauren Raubaugh Jan 2019

Cultural Responsiveness And K-12 English Learners: Exploring Policy And Implementation Fidelity, Lauren Raubaugh

Electronic Theses and Dissertations

This critical policy analysis and collective case study, informed by ethnographic techniques, involved reviews of twelve Florida school district ESOL policies (included within the 2016-2019 District English Language Learner Plans, required of all Florida districts to complete) whose English learner (EL) populations met or exceeded ten percent (10%) of their total enrollment. A priori coding of these policy documents was conducted using nine criteria pulled from the literature on culturally responsive practice (CRP), which served as the theoretical framework for the study. Subsequent observations and practitioner interviews within two schools from the same district were conducted in order to ascertain …

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Non-Hermitian And Space-Time Mode Management, Nicholas Nye Jan 2019

Non-Hermitian And Space-Time Mode Management, Nicholas Nye

Electronic Theses and Dissertations

In the last few years, optics has witnessed the emergence of two fields namely metasurfaces and parity-time (PT) symmetry. Optical metasurfaces are engineered structures that provide unique responses to electromagnetic waves, absent in natural materials. On the other hand, PT symmetry has emerged from quantum mechanics, when a new class of non-Hermitian Hamiltonian quantum systems was shown to have real eigenvalues. In this work, we demonstrate how PT-symmetric diffractive structures are capable of eliminating diffraction orders in specific directions, while maintaining/enhancing the remaining orders. In the second part of this work, we emphasize on supersymmetry (SUSY) and its applications in …

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Metastable-State Photoacids: Synthesis, Properties, And Applications, Parth Patel Jan 2019

Metastable-State Photoacids: Synthesis, Properties, And Applications, Parth Patel

Electronic Theses and Dissertations

Reversible photochromic compounds have the ability to reversibly change its color when it absorbs photons of a particular wavelength. This process of color change is a consequence of structural changes within the compound, such as cis-trans photo-isomerization. Some examples of photochromic compounds are spiropyrans, spirooxazines, diarylethenes and azobenzenes. These compounds have been extensively studied for decades, and are used in various applications such as biomedicine, chemical sensors and harvesting solar energy. However, majority of photochromic compounds are initially activated by ultraviolet (UV) light. The use of UV light is harmful for biological applications and photo-degrade the compound over repeated use. …

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Evaluating Pedagogical Methods That Influence Homework Assignment Completion, Kirk Sawyer Jan 2019

Evaluating Pedagogical Methods That Influence Homework Assignment Completion, Kirk Sawyer

Electronic Theses and Dissertations

College students enrolled in an online introductory engineering course are not completing their homework assignments at an acceptable rate which impacts them, the instructor, and the college. This research study employed a quasi-experimental evaluation model to assess the effectiveness of two pedagogical methods designed to positively influence student homework completion rates and student attitudes toward homework. Despite evidence that grading penalties encourage students to submit their homework assignments, such strategies have historically been unsuccessful for the course used in this study. The researcher designed two pedagogical interventions, along with a survey instrument, to measure the impact of the interventions on …

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A Survey Of Investing And Retirement Knowledge And Preferences Of Florida Preservice Teachers, Richard Thripp Jan 2019

A Survey Of Investing And Retirement Knowledge And Preferences Of Florida Preservice Teachers, Richard Thripp

Electronic Theses and Dissertations

New teachers are facing lower pay and less generous retirement benefits than the prior generation, yet their financial and retirement knowledge, concerns, and preferences have received little attention. To investigate these areas, the author developed a 39-item survey instrument and administered it to 314 preservice teachers in undergraduate teacher education courses at the University of Central Florida, who were primarily female elementary and early childhood education juniors and seniors ages 18–25. Florida public employees are offered an unusual choice between a traditional pension plan and a defined-contribution plan similar to a 401(k) in which they can select their own investments, …

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The Aftermath: A Culturally Responsive Mathematical Intervention To Aid Students Affected By Natural Disasters, Brianna Kurtz Jan 2019

The Aftermath: A Culturally Responsive Mathematical Intervention To Aid Students Affected By Natural Disasters, Brianna Kurtz

Electronic Theses and Dissertations

On September 20, 2017, Hurricane Maria struck the island of Puerto Rico. The damage was extensive, and many people found themselves to be natural disaster refugees. As a result, schools in Central Florida saw an influx of new students who had their educations interrupted by the disaster and now were resuming school in a new language of instruction. These students not only faced linguistic challenges but also academic differences due to the high prevalence of poverty and the effects of neocolonialism in their previous schooling. This mixed methods study implemented an intensive intervention in probability to aid students in developing …

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