Digital Commons Network^™

Manipulating Relative Lmx: Effects On Performance, Conflict, And Strain, Keaton A. Fletcher

USF Tampa Graduate Theses and Dissertations

Fundamental to the conceptualization of leader-membership exchange (LMX), particularly within the context of teams, is that leaders do not necessarily treat each follower equally. Studies that have examined LMX within the context of the team often fail to capture these complexities, or rely exclusively upon self-report, or survey-based data to make inferences. Therefore, it is the purpose of this study to examine the effects of experimentally manipulated relative LMX within teams on individual conflict processes, attitudes, and psychological distress, as well as team-level performance. This study examined conflict processes and outcomes within 113 virtual, project teams engaged in a decision-making …

Application Of Modern Foraminiferal Assemblages To Paleoenvironmental Reconstruction: Case Studies From Coastal And Shelf Environments, Christian Haller

USF Tampa Graduate Theses and Dissertations

The aim of paleoenvironmental studies is to reconstruct characteristics of the past environment from fossil assemblages preserved in sedimentary strata. Thus, studies of modern surface assemblages, quantitatively correlated to the environmental parameters, are required before reliable interpretations can be made. For this dissertation, two different techniques were applied in two case studies: a reconstruction making use of a benthic foraminiferal transfer function from the intertidal marshes in the eastern Mississippi Sound, Alabama/Mississippi, and a qualitative reconstruction of ocean current activity on the Western Australian shelf.

Modern salt-marsh foraminifera were collected from Grand Bay, Pascagoula, Fowl River, and Dauphin Island across …

Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark

USF Tampa Graduate Theses and Dissertations

Florida’s seagrasses are ecologically important marine environments which have suffered major degradation caused by increasing anthropogenic pressures. A 2011 seagrass die-off event caused by an algal bloom in the Florida Indian River Lagoon (IRL) was particularly severe with a majority of seagrass lost in areas such as the Banana River. An understanding of how this coastal marine environment changed is an important step toward better managing resources for conservation. Modern tools and methods provide new opportunities to study these changes at the landscape scale, a scale that informs on the larger more comprehensive state of a system. Classified satellite imagery …

Synthesis, Modification, Characterization And Processing Of Molded And Electrospun Thermoplastic Polymer Composites And Nanocomposites, Tamalia Julien

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on the versatility and integrity of a novel, ultrasoft polycarbonate polyurethane (PCPU) by the introduction of nanoparticles and lithium salts. Additionally, the research takes into account the use of electrospinning as a technique to create PCPU and polyimide (PI) fibers. These polymers are of interest as they offer a wide range of properties and uses within the medical and industrial fields.

An industrial batch of an ultrasoft thermoplastic polyurethane (TPU) was synthesized using a two-step process. The first was to create an end capped pre-polymer from methylene bis (4-cyclohexylisocyanate), and a polycarbonate polyol made up of 1,6- …

Geochemical Modeling Of Primary Morb Magmas: Implications For Parental Melting Regimes In Melt Lenses Along-Axis Of The Hess Deep Rift, Stephanie Michelle Drumm

USF Tampa Graduate Theses and Dissertations

The Hess Deep Rift in the East Pacific Rise is a mid-ocean ridge spreading center that produces melts which exhibit geochemical characteristics of evolved MORB. Using basaltic glass samples collected from multiple dive cruises that explored Hess Deep geology, volatile and chemical data were collected at USF using FTIR and EMPA, respectively. In addition, a data suite of samples of glass from Hess Deep were compiled from the EarthChem database. The intention was to use the data suite and models to compare the Hess Deep regime to analog models for mid-ocean ridge crystallization regimes and tectonic structures. The USF and …

The Stability Of Sand Waves In A Tidally-Influenced Shipping Channel, Tampa Bay, Florida, John Willis Gray

USF Tampa Graduate Theses and Dissertations

Tidally-influenced sandwaves are common coastal features present in various settings, including shipping channels. The main shipping channel in Tampa Bay under the Bob Graham Sunshine Skyway Bridge (a.k.a. the Skyway Bridge) contains such sandwave bedforms. Between the years 2000 and 2017, these bedforms have been surveyed with multibeam echosounders (MBES) on 21 occasions with ranging coverage and quality of returns. Surveys between 2000 and 2009 used a 300 kHz Kongsberg EM3000; surveys between 2015 and 2017 used a 400 kHz Reson Seabat 7125. For comparable surveys, bathymetry, backscatter, slope, curvature, planform curvature, and profile curvature maps were created and analyzed. …

Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca

USF Tampa Graduate Theses and Dissertations

Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice …

Adolescents’ Perceptions Of Parenting Practices And Their Influence On Success, Academic Motivation, And School Belonging, David Rubio Jr.

USF Tampa Graduate Theses and Dissertations

Although academic motivation and school belonging positively influence student adjustment and experiences in school, early adolescence marks a time when motivation, belonging, and success in school tend to decline. Research has investigated ways that teachers and peers can support school success and student adjustment. However, there is less research on the role that parents play in supporting students’ success, motivation, and belonging in middle school. Additionally, most research examining the role of parents has focused on parenting styles rather than parenting practices (e.g., parental involvement and parental monitoring). Our understanding of the ways that specific parenting practices may support success, …

Promoter Effects On Iron-Based, Sba-15 Supported Ultra-High Temperature Fischer- Tropsch Catalysts, David P. Weber

USF Tampa Graduate Theses and Dissertations

Promoter effects on SBA-15 supported iron Fischer-Tropsch catalysts were investigated for their potential to improve high temperature catalyst performance. FTS catalysts promoted by manganese (0.15%-1.4%), copper (0.15%-1%), and potassium (0.5%-3%), with all percentages stated on the basis of mass percentage of final catalysts, were prepared and tested at 430°C and ambient pressure in a fixed bed reactor. Manganese showed the ability to promote the FT reaction, increasing both the CO conversion and the average chain length of hydrocarbon products. Compared to the unpromoted catalyst composed only of iron supported on SBA-15, 1.4%Mn (mass) promotion of 15% (mass) iron on SBA-15 …

Improving The Security Of Building Automation Systems Through An Sel4-Based Communication Framework, Richard Habeeb

USF Tampa Graduate Theses and Dissertations

Existing Building Automation Systems (BASs) and Building Automation Networks (BANs) have been shown to have serious cybersecurity problems. Due to the safety-critical and interconnected nature of building subsystems, local and network access control needs to be finer grained, taking into consideration the varying criticality of applications running on heterogeneous devices. In this paper, we present a secure communication framework for BASs that 1) enforces rich access control policy for operating system services and objects, leveraging a microkernel-based architecture; 2) supports fine-grained network access control on a per-process basis; 3) unifies the security control of inter-device and intra-device communication using proxy …

Optimal Latin Hypercube Designs For Computer Experiments Based On Multiple Objectives, Ruizhe Hou

USF Tampa Graduate Theses and Dissertations

Latin hypercube designs (LHDs) have broad applications in constructing computer experiments and sampling for Monte-Carlo integration due to its nice property of having projections evenly distributed on the univariate distribution of each input variable. The LHDs have been combined with some commonly used computer experimental design criteria to achieve enhanced design performance. For example, the Maximin-LHDs were developed to improve its space-filling property in the full dimension of all input variables. The MaxPro-LHDs were proposed in recent years to obtain nicer projections in any subspace of input variables. This thesis integrates both space-filling and projection characteristics for LHDs and develops …

Reduction In Needlestick Injuries Using A Novel Package Of Interventions, Kamal Thakor Patel

USF Tampa Graduate Theses and Dissertations

In 2015 Dr. Pratiksha Vaghela started the “Stop Poking Me” campaign which was aimed at curbing the increase in the number of needlesticks at the James A. Haley Veteran Affairs Hospital (JAHVA). The data for needlesticks was collected by the Occupational Medicine Clinic (OMC) between Oct 2013 and Oct 2016. We then obtained the original data from Dr. Vaghela’s project and compared the data to assess whether the new implementations have truly decreased the number of needlesticks. There was a 23.6% reduction in the number of needlesticks between 2013 and 2016 and even more importantly a 60.1% reduction between 2015 …

Coloring In The Margins: Understanding The Experiences Of Racial/Ethnic And Sexual/Gender Minority Undergraduates In Stem, Jonathan D. Ware

USF Tampa Graduate Theses and Dissertations

Extensive research has documented the experiences and outcomes of women and certain underrepresented racial/ethnic minority groups in STEM educational programs. This paper contributes to current conversations by focusing on the experiences of individuals that identify as both a racial/ethnic and sexual/gender minority (SGM). This paper has two major objectives in mind: (1) provide one of the first empirical studies examining the experiences of SGM students in STEM and (2) interrogate the intersection of racial/ethnic identity and sexual/gender identity within the context of these programs. In order to provide a more robust understanding in these areas, this paper is guided by …

Design, Synthesis, Application Of Biodegradable Polymers, Mussie Gide

USF Tampa Graduate Theses and Dissertations

Bacterial infections have posed a serious threat to the public health due to the significant rise of the infections caused by antibiotic-resistant bacteria. There has been considerable interest in the development of antimicrobial agents which mimic the natural HDPs, and among them biodegradable polymers are newly discovered drug candidates with ease of synthesis and low manufacture cost compared to synthetic host defense peptides. Herein, we present the synthesis of biocompatible and biodegradable polymers including polycarbonate polymers, unimolecular micelle hyperbranched polymers and dendrimers that mimic the antibacterial mechanism of HDPs by compromising bacterial cell membranes. The developed amphiphilic polycarbonates are highly …

Quantifying The Effect Of Topographic Slope On Lava Flow Thickness: A First Step To Improve Lava Flow Volume Estimation Methods, Steven R. Rizo

USF Tampa Graduate Theses and Dissertations

The volume of lava flows provide important information on the magnitude of volcanic eruptions, and accurate volumes are necessary to produce reliable models of lava flow emplacement or constrain the internal structure of volcanoes. The most accurate lava flow volumes are obtainable when the topography before and after an eruption are both known, but information for the topography before lava flow emplacement is absent in non-historic lava flows. To calculate the volume of non-historic lava flows, this pre-emplacement topography needs to be reconstructed. Common methods for this include using inverse distance-weighted averages or global polynomial interpolation methods, but these can …

Reconstructing Historical Hurricane Tracks In The Atlantic Basin: Three Case Studies From The 1840s, Emily L. Cerrito

USF Tampa Graduate Theses and Dissertations

Analyzing past tropical cyclone activity enables researchers to recognize patterns of hurricane variability, estimate hurricane return periods, and assess local risk to future storms. This paleotempestology study used original primary data to make the historical record as comprehensive and accurate as possible for three major hurricanes: October 1844, October 1846, and September 1848. This thesis presents the reconstructed storm tracks, assesses the societal impacts, and evaluates the storm intensity of these three major hurricanes for the eastern U.S. and Cuba. The data utilized in this study include ship logbooks, newspapers, diaries, and instrumental meteorological records. A geographic information system (GIS) …

A Point Cloud Approach To Object Slicing For 3d Printing, William Edward Oropallo Jr.

USF Tampa Graduate Theses and Dissertations

Various industries have embraced 3D printing for manufacturing on-demand, custom printed parts. However, 3D printing requires intelligent data processing and algorithms to go from CAD model to machine instructions. One of the most crucial steps in the process is the slicing of the object. Most 3D printers build parts by accumulating material layers by layer. 3D printing software needs to calculate these layers for manufacturing by slicing a model and calculating the intersections. Finding exact solutions of intersections on the original model is mathematically complicated and computationally demanding. A preprocessing stage of tessellation has become the standard practice for slicing …

Modeling Corrosion Damage And Repair To A 3, Joseph R. Scott

USF Tampa Graduate Theses and Dissertations

The main purpose of this study was to investigate and implement a repair design for corrosion damaged bridge bents in order to resist lateral loading, such as wind loads or ship impact. Using the results from a one-third scale bridge bent constructed and tested for a previous study, non-linear modeling was used to simulate the same corrosion damage and load response. The principle variable considered was damage, represented as a percent of effective area loss of prestressing steel within a designated damage zone along the length of piles. Other influencing variables included: prestress transfer length, localized loss in prestress due …

General Education Teachers’ Perceptions Of Response To Intervention Implementation: A Qualitative Interview Study, Adhwaa Alahmari

USF Tampa Graduate Theses and Dissertations

The purpose of this interview study was to explore teachers’ perceptions of Response to Intervention (RtI) implementation in their school. Particularly, the study explored teachers’ knowledge of RtI, teachers’ perceptions of RtI tiers intervention/instruction in their school, and teachers’ suggestions of RtI implementation in their school. The study design was a qualitative interview study and data were collected from the face-to-face interviews with four teachers in one school. Findings revealed that RtI is meant to identify students’ problems. Positive teachers’ perceptions of their implementation included: (a) Students who demonstrate progress through RtI, (b) Students who receive special education services, (c) …

Comparison Of Functional Porous Organic Polymers (Pops) And Natural Material Zeolite For Nitrogen Removal And Recovery From Synthetic Urine, Yan Zhang

USF Tampa Graduate Theses and Dissertations

Urine comprises around 1% of domestic sewage volume but holds 80% of total nitrogen. Source separation is a sustainable way to wastewater management than traditional way due to low energy cost and preventing certain pollutants into wastewater treatment plants. Currently, removing and recovering nitrogen from source-separated urine has attracted more and more interests. Of them, ion exchange was used for removal and recovery of nitrogen in the form of ammonia from synthetic urine for potential application as a fertilizer in agriculture. No previous research studies were conducted to investigate the removal and recovery of nitrogen from hydrolyzed urine by ion …

Conversion Of Biomass To Liquid Hydrocarbon Fuels Via Anaerobic Digestion: A Feasibility Study, Ahmad Naqi

USF Tampa Graduate Theses and Dissertations

The use of biomass as a potential feedstock for the production of liquid hydrocarbon fuels has been under investigation in the last few decades. This paper discusses a preliminary design and a feasibility study of producing liquid hydrocarbon fuels from biomass through a combined biochemical and thermochemical route. The process involves anaerobic digestion (AD) of the biodegradable portion of the biomass to produce methane rich gas. The methane rich biogas stream is purified by removing contaminants and upgraded to liquid hydrocarbon fuel in a gas to liquid facility (GTL) via thermochemical conversion route. The biogas conversion involves two major steps: …

Developing Motion Platform Dynamics For Studying Biomechanical Responses During Exercise For Human Spaceflight Applications, Kaitlin Lostroscio

USF Tampa Graduate Theses and Dissertations

In future human spaceflight missions, with prolonged exposure to microgravity, resistive and aerobic exercises will be countermeasures for bone loss, muscle loss, and decreased aerobic capacity. Two of the exercises of interest are squats and rowing. The cyclic forces produced during these exercises are at relatively low frequencies which are likely to excite structural resonances of space vehicles. Vibration Isolation Systems (VIS) are being designed to be paired with future exploration exercise devices in order to prevent these cyclic exercise forces from impacting the space vehicle. The VIS may be configured such that a platform supports the human and exercise …

Parallelizing Tabu Search Based Optimization Algorithm On Gpus, Vinaya Malleypally

USF Tampa Graduate Theses and Dissertations

There are many combinatorial optimization problems such as traveling salesman problem, quadratic-assignment problem, flow shop scheduling, that are computationally intractable. Tabu search based simulated annealing is a stochastic search algorithm that is widely used to solve combinatorial optimization problems. Due to excessive run time, there is a strong demand for a parallel version that can be applied to any problem with minimal modifications. Existing advanced and/or parallel versions of tabu search algorithms are specific to the problem at hand. This leads to a drawback of optimization only for that particular problem. In this work, we propose a parallel version of …

An Exploration Of The Relationship Between Institutional Financial Resources And Global Ranking, Matthew S. Anderson

USF Tampa Graduate Theses and Dissertations

Global rankings are a popular way for governments, HEI’s, faculty, staff, and students to compare institutions worldwide, therefore it is important to rank well. However, in order to have top-quality research and education programs, HEI’s need to have significant financial resources. The purpose of this study was to explore the relationship between an institution’s financial resources and its global ranking. The results of this study provide additional insight and a better understanding of global rankings and the nature of the relationship between various financial resources and global rankings.

This was a quantitative study that used ranking data from the Academic …

Performance Evaluation Of Choice Set Generation Algorithms For Modeling Truck Route Choice: Insights From Large Streams Of Truck-Gps Data, Divyakant Tahlyan

USF Tampa Graduate Theses and Dissertations

This thesis evaluates truck route choice set generation algorithms and derives guidance on using the algorithms for effective generation of choice sets for modeling truck route choice. Specifically, route choice sets generated from a breadth first search link elimination (BFS-LE) algorithm are evaluated against observed truck routes derived from large streams of GPS traces of a sizeable truck fleet in the Tampa Bay region of Florida. A systematic evaluation approach is presented to arrive at an appropriate combination of spatial aggregation and minimum number of trips to be observed between each origin-destination (OD) location for evaluating algorithm-generated choice sets. The …

Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare

USF Tampa Graduate Theses and Dissertations

Perovskite-type oxides show irrefutable potential for feasible thermochemical solar-driven CO₂ conversion. These materials exhibit the exact characteristics required by the low temperature reverse water-gas shift chemical looping process. These properties include structural endurance and high oxygen redox capacity, which results in the formation of numerous oxygen vacancies, or active sites for CO₂ conversion. A major drawback is the decrease in oxygen self-diffusion with increasing perovskite particle size. In this study, the La_0.75Sr_0.25FeO₃ (LSF) perovskite oxide was combined with various supports including popular redox materials CeO₂ and ZrO₂ along with more abundant …

Design And Implementation Of A Ferrocement Improved Cookstove In Rural Panama, Josh Donegan

USF Tampa Graduate Theses and Dissertations

Household air pollution contributes to the premature death of more than 4 million people annually. Improved cookstoves are one technological intervention that can potentially reduce exposure to household air pollution. However, improved cookstove implementation programs need to consider measures to increase sustainability and promote long-term adoption. The objectives of this research were 1) to develop and implement a new ferrocement cookstove for Peña Blanca, a rural indigenous community in the Ngäbe-Bugle region of Panama, 2) to evaluate its potential sustainability in comparison to the most common cooking technologies observed in the community, 3) to prepare a construction manual for the …

Design Of Micro-Scale Energy Harvesting Systems For Low Power Applications Using Enhanced Power Management System, Majdi M. Ababneh

USF Tampa Graduate Theses and Dissertations

The great innovations of the last century have ushered continuous progress in many areas of technology, especially in the form of miniaturization of electronic circuits. This progress shows a trend towards consistent decreases in power requirements due to miniaturization. According to the ITRS and industry leaders, such as Intel, the challenge of managing and providing power efficiency still persist as scaling down of devices continues. A variety of power sources can be used in order to provide power to low power applications. Few of these sources have favorable characteristics and can be designed to deliver maximum power such as the …

Adult College Students' Perceptions About Learning Mathematics Via Developmental Mathematical Xmoocs, Pelagia Alesafis Kilgore

USF Tampa Graduate Theses and Dissertations

Debates over the promising change Massive Open Online Courses (MOOCs) might offer to traditional online learning now produce significant attention and discourse among the media and higher education. Ample articles discuss the potential benefits of MOOCs from the perspectives of faculty and administration. However, little is known about students’ perceptions of MOOCs. Given the lack of relevant literature and the reality that MOOCs are created to benefit students, it is important to elicit current college students’ perceptions of MOOCs since it is well documented learning mathematics online has its problems (Ashby, Sadera, & McNary, 2011; Frame, 2012; Ho et al., …

Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones

USF Tampa Graduate Theses and Dissertations

After the notorious outbreak and discovery of Legionella bacteria in 1976, the waterborne pathogen was added to the list of disease-causing agents associated with the built environment. Legionella pneumophila was discovered when it was identified as the agent that caused 34 deaths and an outbreak of pneumonia-like symptoms in several attendees of the 1976 American Legion Convention held in Philadelphia (OSHA, 2017).

Recently published data from the year 2015 reported more than 6,000 Legionnaires’ cases identified in the United States (CDC, 2016). This is a concerning number given that one in every ten infected persons will die of the disease. …