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Modeling And Assessing Lava Flow Hazards, Elisabeth Gallant

USF Tampa Graduate Theses and Dissertations

Lava flow hazards are one of the few constant themes across the wide spectrum of volcanic research in the solar system. These dynamic hazards are controlled by the location of the eruption, the topography and material properties of the land upon which the flow spreads, and the properties of the lava (e.g., volume, temperature, and rheology). Understanding the influences on eruption location and how lava flows modify the landscape are important steps to accurately forecast volcanic hazards. Three studies are presented in this dissertation that address di˙erent aspects of modeling and assessing vent opening and lava flow hazards.

The first …

An Evaluation Of The Effects Of A Student Trajectory Enhancement Program (Step Up) On High School Performance, Odalys G. Pritchard

USF Tampa Graduate Theses and Dissertations

The Student Trajectory Enhancement Program (STEP UP) was launched in 2014 by Hillsborough County Public Schools (HCPS) as a six-week summer program that targeted over-age, retained, potentially under-achieving students completing the sixth grade. The purpose of this study was to conduct a summative evaluation of the effectiveness of the STEP UP program in keeping program participants “on track” for high school graduation and to determine if the intended goals of the program were realized.

STEP UP was developed in response to compelling data that there is an unacceptably high number of overage students in middle school in HCPS. STEP UP …

Framing Geologic Numeracy For The Purpose Of Geoscience Education: The Geoscience Quantitative Preparation Survey, Victor J. Ricchezza

USF Tampa Graduate Theses and Dissertations

The Geoscience Quantitative Preparation Survey (GQPS) was developed to address a deficiency in the available literature regarding the competency and preparation of early-career geologists in geoscience job-related quantitative skills – namely, geologic numeracy. The final version of the GQPS included self-confidence, usage, satisfaction, and demographic sections. The GQPS was expected to produce data that would allow for an evaluation of the geologic numeracy of early-career geologists and the success of approximately 20 years of increased focus on quantitatively literate geoscience graduates.

The self-confidence section of the GQPS included quantitative methods and quantitative skills. The usage section asked whether participants used …

A Machine Learning Approach To Predicting Community Engagement On Social Media During Disasters, Adel Alshehri

USF Tampa Graduate Theses and Dissertations

The use of social media is expanding significantly and can serve a variety of purposes. Over the last few years, users of social media have played an increasing role in the dissemination of emergency and disaster information. It is becoming more common for affected populations and other stakeholders to turn to Twitter to gather information about a crisis when decisions need to be made, and action is taken. However, social media platforms, especially on Twitter, presents some drawbacks when it comes to gathering information during disasters. These drawbacks include information overload, messages are written in an informal format, the presence …

Tracking Sediment Bypassing, Geomorphological Analysis, And Regional Sediment Management At Tidal Inlets, Tanya M. Beck

USF Tampa Graduate Theses and Dissertations

Tidal inlets on sandy shorelines separate barrier islands and serve as a conduit for transport of sand and water between embayments and oceans, seas, or other tidally influenced waterbodies. Tides and waves induce currents along the coastline that transport sediment across-shore and alongshore. Coastal managers must optimize barrier-inlet system stability while conserving limited sediment resources, and often base management decisions and engineering design upon geomorphic and numerical models that predict the morphological behavior of tidal inlets on short-to-medium timescales (years to decades). The overall goal of this study was threefold. First, to provide science-based practical guidance for regional sediment management …

Exploring New Teacher Beliefs: Identity, Home-Life, And Culture In The Classroom, Frederick B. Bradley Iii

USF Tampa Graduate Theses and Dissertations

A persistent shortage of science, technology, engineering, and math (STEM) students, teachers, and professionals is seen by many as a threat to the nation’s global economic standing. Deficits in these areas are often attributed to a lack of quality K-12 STEM education, which is due in large part to a high rate of teacher turnover. Moreover, such teacher attrition has been shown to occur far more often in high-need schools and districts; thus serving to further marginalize disadvantaged members of society.

This study occurs within the context of The Robert Noyce Scholarship Program at our research-intensive university in the southeastern …

Beyond Labels And Captions: Contextualizing Grounded Semantics For Explainable Visual Interpretation, Sathyanarayanan Narasimhan Aakur

USF Tampa Graduate Theses and Dissertations

One of the long-standing problems in artificial intelligence is the development of intelligent agents with complete visual understanding. Understanding entails recognition of scene attributes such as actors, objects and actions as well as reasoning about the common semantic structure that combines these attributes into a coherent description. While significant milestones have been achieved in the field of computer vision, majority of the work has been concentrated on supervised visual recognition where complex visual representations are learned and a few discrete categories or labels are assigned to these representations. This implies a closed world where the underlying assumption is that all …

Iron-Virus Interactions: Development And Testing Of The Ferrojan Horse Hypothesis, Chelsea Bonnain

USF Tampa Graduate Theses and Dissertations

Iron is an essential micronutrient for phytoplankton metabolism that limits growth in many regions of the surface ocean. More than 99.9% of oceanic dissolved iron is organically complexed to an iron-binding ligand, many of which have yet to be characterized. This thesis puts forth the Ferrojan Horse Hypothesis, which predicts a role for marine phages in oceanic iron cycling. Based on evidence from non-marine model systems, the Ferrojan Horse Hypothesis suggests that some marine phages (short for bacteriophages, or viruses that infect bacteria) can use iron as a “Trojan Horse” to gain access to host siderophore-bound iron receptors for infection. …

International Teaching Assistants’ Perceptions Of English And Spanish Language Use At The University Of Puerto Rico-Mayagüez, Edward G. Contreras Santiago

USF Tampa Graduate Theses and Dissertations

Globalization and sociopolitical factors impact migration patterns all over the world. In Puerto Rico, these factors created superdiverse environments where languages users have pushed the boundaries of language in order to make sense of their worlds. Even though this language dynamic is natural for locals, it is those who visit from different countries, specifically international graduate students, that have a difficult time adjusting to Puerto Rico’s rich use of English and Spanish. Understanding how international graduate students perceive the language used at the University of Puerto Rico, Mayagüez (UPRM) upon arrival is essential to provide a better experience for future …

Reconstruction Of Radar Images By Using Spherical Mean And Regular Radon Transforms, Ozan Pirbudak

USF Tampa Graduate Theses and Dissertations

The goal of this study is the recovery of functions and finite parametric distributions from their spherical means over spheres and designing a general formula or algorithm for the reconstruction of a function f via its spherical mean transform. The theoretical study is and supported with a numerical implementation based on radar data. In this study, we approach the reconstruction problem in two different way. The first one is to show how the reconstruction problem could be converted to a Prony-type system of equations. After solving this Prony-type system of equations, one can extract the parameters that describe the corresponding …

A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei

USF Tampa Graduate Theses and Dissertations

Water shortage, water contamination, and the emerging challenges in sustainable water resources management (e.g., the likely impacts of climate change and population growth) necessitate adopting a reverse logistics approach, which is the process of moving wastewater from its typical final destination back to the water supply chain for reuse purposes. This practice not only reduces the negative impacts of wastewater on the environment, but also provides an alternative to withdrawal from natural water resources, forming a closed-loop water supply chain. However, the design of such a supply chain requires an appropriate sustainability assessment, which simultaneously accounts for economic, environmental, and …

Sinkhole Lake Infiltration Of Contaminants Of Emerging Concern From Onsite Water Treatment Systems, Ethan A. Upton

USF Tampa Graduate Theses and Dissertations

The advancement in synthetic chemicals commonly referred to as contaminants of emerging concern (CECs) and their application has led to an increase in environmental pollution. The use of septic tanks otherwise referred to as onsite water treatment systems (OWTS), promotes the introduction of CECs into the environment while allowing little in the way of remediation. In order to study the impacts of CECs from OWTS as they infiltrate the environment and the aquifer system, water, sediment, and vegetation samples were collected around a sinkhole lake surrounded by residential housing using OWTSs. The main question of this research project is what …

Rf Power Circuit Designs For Wi-Fi Applications, Krishna Manasa Gollapudi

USF Tampa Graduate Theses and Dissertations

In the field of RF/Microwave Engineering, the Wilkinson Power divider is a passive device frequently used for splitting or combining signals. The power fed to the input port is equally or unequally split between N output ports and delivers better performance by achieving isolation between the output ports while matching all the ports. The design comprises simple transmission lines and provides power divider characteristics with the help of quarter wavelength transmission lines with different topologies.

This thesis describes the design and fabrication of lumped and N way power splitter working at an operating frequency of 2.4 GHz. These circuits are …

The Design Of Passive Networks With Full-Wave Component Models, Eric Valentino

USF Tampa Graduate Theses and Dissertations

In this thesis, the design of passive networks with the aid of full-wave simulation software and geometry-based models of lumped elements is investigated. This is done by examining the results of a number of simulation examples, as well as measured data from manufactured designs to compare against simulated equivalents. One such example is a chip antenna evaluation board design, in which the PCB, antenna, matching components and connector are all modeled. When measured, the simulation agreed with the board’s best matched frequency of 5.5 GHz to within 20 MHz. In another, a new antenna layout is generated from an existing …

Bridging The Achievement Gap: Promoting Equity In Teachers' Use Of Behavior-Specific Praise With Self-Monitoring And Performance Feedback, Ashley E. Knochel

USF Tampa Graduate Theses and Dissertations

Disparities in academic and social outcomes for ethnically diverse students in educational settings has been identified in the literature as the achievement gap. This study examined the impact of teacher training interventions on establishing equity in teacher implementation of a common positive behavior classroom support strategy, behavior-specific praise in four elementary classrooms. Teacher self-monitoring and written performance feedback were used to facilitate teachers to improve classroom practices by establishing proportionate praise and discipline practices across racially diverse students. A multiple-baseline across participants design was used to evaluate the impact of self-monitoring and written performance feedback with and without equity-focused procedures …

The Distribution And Biogeochemistry Of Subtropical Intertidal Microbial Mats, Bert D. Anderson

USF Tampa Graduate Theses and Dissertations

Microbial mats have played an important role in the carbon (C) and nutrient cycles since the Archean Eon and modern mats are important contributors to the biogeochemistry of intertidal wetlands. Microbial mats are flat assemblages of microbes that are currently found in many unvegetated habitats globally. Intertidal salt pans are a common habitat for microbial mats, however little is known about the distribution of microbial mats within the intertidal landscape. Understanding the spatial distribution of microbial mats is critical to developing quantitative estimates of the impacts of microbial mats on their ecosystems. We photographically measured the presence and density of …

Habitat Suitability Index Model Of The Florida Sandhill Crane (Grus Canadensis Pratensis) In West-Central Florida, Courtney E. Buck

USF Tampa Graduate Theses and Dissertations

The Florida Sandhill Crane (Grus canadensis pratensis) is a state threatened endemic subspecies of the Sandhill Crane (Nesbitt & Tacha, 1997). With a population that was estimated at a maximum of 5,000 individuals in 2003 (Nesbitt & Hatchitt, 2008), it is imperative to identify potentially viable habitats, as Florida is rapidly developing. This research develops a Habitat Suitability Index model to determine unsuitable to optimally suitable habitat locations throughout west-central Florida. To do so, six suitability variables based on the crane’s life history were evaluated: Potential nesting area, immediate nesting area, wetland coverage, foraging area, brooding area, and road proximity. …

Increasing Engagement And Academic Performance Of Children With Autism Spectrumdisorder And Attention Difficulties: Do Fidget Spinners Help?, Melanie Byrne B.S.

USF Tampa Graduate Theses and Dissertations

Children with varying exceptionalities including ADHD, Autism Spectrum Disorder, and other learning disabilities often struggle with attention deficits. The persistence of alternative non-behavioral approaches in classrooms to address this deficit presents the need for more research and education about these interventions. Specifically, the fidget spinner is a newer intervention which currently has no empirical evidence to support its use in the classroom setting. The purpose of this study was to examine the effects of fidget spinners on increasing engagement and academic comprehension in a whole classroom environment. A multiple baseline across participants design was used with six children with varying …

Power Graphs Of Quasigroups, Dayvon L. Walker

USF Tampa Graduate Theses and Dissertations

We investigate power graphs of quasigroups. The power graph of a quasigroup takes the elements of the quasigroup as its vertices, and there is an edge from one element to a second distinct element when the second is a left power of the first. We first compute the power graphs of small quasigroups (up to four elements). Next we describe quasigroups whose power graphs are directed paths, directed cycles, in-stars, out-stars, and empty. We do so by specifying partial Cayley tables, which cannot always be completed in small examples. We then consider sinks in the power graph of a quasigroup, …

Play Behaviors In Latino Dual Language Learners: The Relationship Between Maternal Characteristics And Classroom Peer Play, Olivia Hernandez Gonzalez

USF Tampa Graduate Theses and Dissertations

In Head Start, 28.8% of the children enrolled are Dual Language Learners (DLLs), and 84.4% of those speak Spanish as their home language. However, there are limited studies involving DLLs. Using the Ecological Model of Human Development framework with current revisions with culture as part of the microsystem (Bronfenbrenner, 1994; Vélez-Agosto et al., 2017), the current study aimed to identify maternal level factors that may relate to Latinos' classroom peer play while controlling for classroom quality. Forty-five Latino DLL children attending Head Start, their mothers, and their teachers participated in the study. Head Start administrators provided their most recent vocabulary …

Changing High School Science Teacher Beliefs On Student Voice Through Action Research, Katie Laux

USF Tampa Graduate Theses and Dissertations

The purpose of this dissertation research was to explore how engagement in action research influenced high school science teachers’ beliefs and classroom practices related to student voice and participation. This included exploring any affordances or obstacles they experienced with attempting to increase student voice and participation in their classrooms. I facilitated individual action research projects with the teachers, and they were able to discuss individual action research plans and share ideas with colleagues. Four high school science teachers began this research. While all four teachers were selected as cases, only two of the teachers designed and followed through with their …

Synthesis, Discovery And Delivery Of Therapeutic Natural Products And Analogs, Zachary P. Shultz

USF Tampa Graduate Theses and Dissertations

Small molecule drug discovery relies heavily on synthetic organic chemistry to develop novel chemical entities that elicit desirable therapeutic effects. The development of targeted chemical syntheses is of paramount importance to access molecules for biological evaluation and is usually considered the bottleneck in most drug discovery campaigns. Targets for chemical syntheses commonly draw inspiration from molecules of natural origin. Nature harbors a wealth of chemical diversity that has established itself over millions of years through chemical and biological evolution. Organisms have an inherent ability to protect themselves from predators and harmful environments. In doing so, many of them evolve to …

Rethinking Map Literacy And An Analysis Of Quantitative Map Literacy, Ming Xie

USF Tampa Graduate Theses and Dissertations

Maps are increasingly being used in traditional and virtual media, and civic discourse on political, social, and environmental issues, among others, is more and more becoming influenced by them. The often-used expression of a “picture tells a 1000 words” has never been so apt in our progressively more visual world. Despite this increased role and importance of maps, map literacy, as a field of research, remains rather underdeveloped. This is especially so for thematic maps, the very type of map that is finding increasing currency in discourse. As part of this under-developed nature of map literacy, the quantitative skills used …

On Distributed Control Of Multiagent Systems Under Adverse Conditions, Emre Yildirim

USF Tampa Graduate Theses and Dissertations

The objective of this thesis is (1) to show the experimental validation of recently proposed distributed adaptive control architecture for a class of heterogeneous uncertain multiagent systems as well as (2) to theoretically propose a proportional integral controller for multiagent systems having limited resources in the presence of a disturbance with stability analyses.

With regard to (1), the distributed adaptive control architecture used in the experiment utilizes a control input having a nominal part and an adaptive augmentation part for each agent to suppress the effect of uncertainties and disturbances effectively. This architecture is capable to provide uniform ultimate boundedness …

An Optimal Medium-Strength Regularity Algorithm For 3-Uniform Hypergraphs, John Theado

USF Tampa Graduate Theses and Dissertations

Szemere´di’s Regularity Lemma [32, 33] is an important tool in combinatorics, with numerous appli- cations in combinatorial number theory, discrete geometry, extremal graph theory, and theoretical computer science.

The Regularity Lemma hinges on the following concepts. Let G = (V, E) be a graph and let ∅ /= X, Y ⊂ V be a pair of disjoint vertex subsets. We define the density of the pair (X, Y ) by d_G(X, Y ) = |E[X, Y ]|/(|X||Y |) where E[X, Y ] denotes the …

Evolutionary Dynamics Of Influenza Type B In The Presence Of Vaccination: An Ecological Study, Lindsey J. Fiedler

USF Tampa Graduate Theses and Dissertations

Understanding the evolutionary dynamics of influenza type B in human hosts is a public health concern as we strive to minimize the disease burden in seasonal epidemics. Vaccination is considered the best defense against contracting influenza, and everyone over the age of 6 months is advised to get vaccinated before each season. The effect that vaccine-acquired immunity has on the evolution of influenza B remains unclear. In the U.S., vaccine-uptake is irregular across the states, and the differing coverages present an opportunity to study how vaccination influences viral evolution. This thesis analyzes the evolutionary patterns of influenza B in the …

Sorption Of Benzene, Tolueneand Ethylbenzeneby Plasticized Pema And Pema/Pmma Sensing Films Using Aquartz Crystal Microbalance (Qcm) At 298.15k, Deekshitha Adapa

USF Tampa Graduate Theses and Dissertations

Detection of volatile organic compounds (VOC’s) in the environment is important for human health and wellness. Long term exposure of certain VOC’s like benzene, toluene, ethylbenzene and xylene (BTEX) has a severe effect on human health. There are techniques such as gas chromatography, photo ionization, and mass spectroscopy that are time consuming, require gas sampling and are ineffective in real time sensing in air. Acoustic wave devices such as surface acoustic wave (SAW) devices can be used for sensing BTEX compounds in both vapor and liquid phase. The quartz crystal microbalance (QCM) is a low-frequency acoustic wave device, which can …

An Examination Of The Roles Of Classroom Quality And Approaches To Learning On The Early Academic Skills Of Latino Dual Language Learners Enrolled In Head Start, Marcela A. Galicia

USF Tampa Graduate Theses and Dissertations

This thesis examined the relationship between classroom quality, approaches-to-learning, and early academic skills among 384 Latino dual language learners (DLLs) enrolled in Florida Head Start programs. The children were living in low-income homes where Spanish was the primary language spoken by at least one parent. The study analyzed the extent to which approaches-to-learning behaviors moderate early literacy and numeracy skills in Head Start classrooms of varying quality. During the spring of their prek-4 year, the children were administered the English and Spanish Letter-Word Identification and Applied Problems subtests of the WJ-III (Woodcock, McGrew, & Mather, 2001) and the Batería III …

Design And Testing Of A Reciprocating Wind Harvester, Ahmet Topcuoglu

USF Tampa Graduate Theses and Dissertations

Renewable energy sources are vital to reduce dependence on fossil fuels that are harmful for the environment and release greenhouse gases causing global warming. Wind energy is a natural source of energy that is abundant in the environment. While wind turbines are most popular, convenient, and used to harvest energy at large scales, there have been recent studies focusing on harvesting energy from the wind for microdevices. Such micro wind energy harvesters can decrease dependence on batteries.

In this study, a novel, framed flag micro wind harvester was designed and tested, and its behavior at three different wind speeds was …

Demographic Predictors And Reasons For Chronic Absenteeism Amongst Secondary Students With Disabilities, Cashea Holyfield

USF Tampa Graduate Theses and Dissertations

Many students in secondary schools are increasingly impacted by chronic absenteeism. Researchers have consistently concluded that students who are chronically absent are likely to experience negative outcomes such as difficulties in academic achievement, learning, sociability, and mental health (London, Sanchez, & Castrechini, 2016). However, despite the implications of chronic absenteeism, research studies that primarily focus on assessing students with disabilities’ (SWDs) reasons for chronic absenteeism are relatively limited. Although there is some existing research that suggests that SWDs are frequently absent due to health-related reasons, transportation issues, and their perceptions of poor school climate (Erbstein, 2014; Humm-Brundage, Castillo, & Batsche, …