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Full-Text Articles in Physical Sciences and Mathematics

Review Of A Framework For Sustainable Thinking: Is Ql For Citizenship Even Possible?, Nathan D. Grawe Jul 2022

Review Of A Framework For Sustainable Thinking: Is Ql For Citizenship Even Possible?, Nathan D. Grawe

Numeracy

Van Antwerp and Heun's A Framework for Sustainability Thinking offers an extensive collection of data related to sustainability with an emphasis on energy. Intended for a primary audience of undergraduate students, the authors set the data in the context of the IPARX identity which notes that impacts (I) are the product of population (P), affluence (A), resource intensity of economic activity (R), and impact of the resources (X). In addition to being a useful text for seminars focused on sustainability and energy use, the book provides a context for contemplating the roles of expertise vs. general quantitative literacy when addressing …


Assessing Environmental Sensitivity In San Diego County, California, For Bird Species Of Special Concern, Eda Okan Kilic Jun 2022

Assessing Environmental Sensitivity In San Diego County, California, For Bird Species Of Special Concern, Eda Okan Kilic

USF Tampa Graduate Theses and Dissertations

It is widely recognized that desertification constitutes one of the biggest environmental problems on Earth. Desertification negatively impacts the future of humans and other living things all over the globe. Therefore, the assessment of desertification is essential to both monitor and combat desertification. A number of models are routinely applied to assess desertification. The MEDALUS model is one of the most popular approaches, identifying desertification risk based on an environmentally sensitive area index (ESAI) that integrates climate, vegetation, soils, groundwater, and socio-economic factors to obtain an overall rating. The goal of this study was to measure the potential impacts of …


Relationships Among The Community Of Inquiry, Achievement Emotions, And Academic Achievement In Asynchronous Online Learning In Higher Education, David H. Tai Apr 2022

Relationships Among The Community Of Inquiry, Achievement Emotions, And Academic Achievement In Asynchronous Online Learning In Higher Education, David H. Tai

USF Tampa Graduate Theses and Dissertations

This research aimed to investigate how achievement emotions predict, mediate, and affect academic achievement in online learning. Online learning has been proliferating, but little is known about how emotion mediates cognition in the Community of Inquiry framework. Recent progress in cognitive neuroscience provided the theoretical foundation for researchers to investigate emotion's role in online learning, especially academic achievement. The researcher of this study adopted a quantitative non-experimental research design to investigate how achievement emotions mediated, predicted, and affected academic achievement in the Community of Inquiry framework. The Partial Least Square Structure Equation Modeling (PLS- SEM) method was adopted for statistical …


Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin Nov 2021

Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin

USF Tampa Graduate Theses and Dissertations

Currently, a significant challenge with reverse osmosis-based desalination is reducing the energy consumption and environmental impacts of the process. This project analyzed the viability of using pressure-retarded osmosis (PRO) for energy recovery in seawater desalination facilities using brine concentrate (the draw solution) and other water sources (the feed solution) such as wastewater effluent. The primary goal of this project is to decrease the cost and overall energy consumption of seawater desalination through PRO-based energy recovery. Process modeling, statistical and sensitivity analysis, energy and cost analysis, geospatial and GIS analysis, laboratory-scale testing, water quality analysis, SEM-EDS microscopy, computational fluid dynamics (CFD), …


An Assessment Of Nutrient Improvement In Surface Water Due To The Conversion Of Onsite Sewage Treatment And Disposal Systems To Sewerage, Jenelle A. Mohammed Oct 2021

An Assessment Of Nutrient Improvement In Surface Water Due To The Conversion Of Onsite Sewage Treatment And Disposal Systems To Sewerage, Jenelle A. Mohammed

USF Tampa Graduate Theses and Dissertations

Florida represents approximately 12% of all onsite sewage treatment and disposal systems (OSTDS) in the United States. Properly designed, constructed and maintained OSTDS are effective eco- friendly alternatives for the treatment of domestic wastewater from households not serviced by public sewer systems. However, conventional OSTDS are not designed to effectively remove nitrogen. If installed and improperly used, they may contribute other pollutants. OSTDS have also been linked to degraded water quality in some regions. However, it has been difficult to quantify OSTDS impacts on water quality because of various confounding factors such as point and non-point sources of nutrient input. …


Fiber-Based Supercapacitor For Wearable Electronics, Rohit Lallansingh Yadav Jul 2021

Fiber-Based Supercapacitor For Wearable Electronics, Rohit Lallansingh Yadav

USF Tampa Graduate Theses and Dissertations

Supercapacitors are significant devices that are used for energy storage and also have the capability of delivering energy at a faster rate than batteries. The increase in the significance of portable and wearable electronic equipment giving rise to pace in the development of flexible supercapacitor and flexible electrodes in recent years. A fiber-based supercapacitor (FSCs) is one of the most significant devices which have even helped us give pace knowing the properties of supercapacitor. These FSCs are said to have excellent electrochemical properties and flexibility. This did make function it in different forms of individual fibers or integrated textiles which …


Development And Validation Of A Scale To Measure Songwriting Self-Efficacy (Sses) With Secondary Music Students, Patrick K. Cooper Jul 2021

Development And Validation Of A Scale To Measure Songwriting Self-Efficacy (Sses) With Secondary Music Students, Patrick K. Cooper

USF Tampa Graduate Theses and Dissertations

Social cognitive theory was developed to explain how individuals learn, in part, by witnessing the behavior of others. Self-efficacy is a construct within social cognitive theory which indicates the beliefs that an individual can be successful at a task under specific situational demands. The sources of self-efficacy include self-evaluating past experiences to predict future success, comparing our abilities to those around us, the verbal and social feedback we get from others, and the physiological feelings we experience when engaged in or thinking about the task. Measures of self-efficacy have been shown to be accurate predictors of successful learning outcomes, achievement, …


Parallel Computation Of Feynman Path Integrals And Many-Body Polarization With Application To Metal-Organic Materials, Brant H. Tudor Apr 2021

Parallel Computation Of Feynman Path Integrals And Many-Body Polarization With Application To Metal-Organic Materials, Brant H. Tudor

USF Tampa Graduate Theses and Dissertations

The Space Research Group is a computational outfit, and so the work presented herein will reflect that. Much of our simulation code is developed in-house and so what follows is a small exploration of that development—although the physics underpinning our software development is never ignored for long. Following the programming centric work, the code and the physics are put to the test. The final chapter describes a scientific endeavor in which a new, robust force field has been validated. Indeed, the new potential has taken a first step in proving itself by making accurate predictions in what have historically found …


Laser-Induced Modifications In Two-Dimensional Materials, Tariq Afaneh Nov 2020

Laser-Induced Modifications In Two-Dimensional Materials, Tariq Afaneh

USF Tampa Graduate Theses and Dissertations

Atomically thin two-dimensional (2D) materials have attracted a growing interest in the lastdecade from the fundamental point of view as well as their potential applications in functional devices. Due to their high surface-to-volume ratio, the physical properties of 2D materials are very sensitive to the environmental factor such as surrounding media and illumination conditions (e.g. light-mater interaction). In the first part of this dissertation I will present recent advances in developing laser-assisted methods to tune the physical properties of 2D transition metal dichalcogenides (TMDs). We demonstrate laser-assisted chemical modification ultrathin TMDs, locally replacing selenium by sulfur atoms. The photo-conversion process …


Breakthroughs In Obtaining Qm/Mm Free Energies, Phillip S. Hudson Apr 2020

Breakthroughs In Obtaining Qm/Mm Free Energies, Phillip S. Hudson

USF Tampa Graduate Theses and Dissertations

The computation of free energy is pivotal to understanding the fundamental nature of chemical phenomena. That is, whether a specific molecular outcome occurs spontaneously or is inherently unfavorable. The need to do this with consistent accuracy begs for the use of quantum mechanical (QM) methods. However, techniques for directly computing free energy differences with QM or mixed QM/MM methods are untenable, as the computational expense is quite exorbitant. At present, the most feasible approach for obtaining QM/MM free energies is employing the so-called indirect cycle, which relies on accurately computing free energy differences between low (e.g., molecular mechanical, MM) and …


The Experiences Of African American Male Computer Science Majors In Two Year Colleges, Simone Brookins Jenkins Nov 2019

The Experiences Of African American Male Computer Science Majors In Two Year Colleges, Simone Brookins Jenkins

USF Tampa Graduate Theses and Dissertations

As the field of computer science grows and the computing science workforce demands more qualified workers, the United States workforce will require underrepresented minorities to help meet these demands. African American males are a demographic that can help meet this need but there are few of them pursuing computer science careers and successfully graduating with computer science degrees. The purpose of this qualitative study was to examine the experiences of African American male two-year college students who are in pursuit of a degree in computer science. My findings indicated that the study participants’ experiences such as positive interactions with faculty …


Formulation To Application: Thermomechanical Characterization Of Flexible Polyimides And The Improvement Of Their Properties Via Chain Interaction, Alejandro Rivera Nicholls Nov 2019

Formulation To Application: Thermomechanical Characterization Of Flexible Polyimides And The Improvement Of Their Properties Via Chain Interaction, Alejandro Rivera Nicholls

USF Tampa Graduate Theses and Dissertations

In this work, Polyimides were synthesized by incorporating an aromatic diamine monomer with a methylene linker, 4,4'-methylenebis(2,6-dimethylaniline) (MBDMA), to make a robust main chain along with aliphatic polyetherdiamine backbone linkers to reduce rigidity. The polymers were designed to exhibit thermal properties in between those of conventional aromatic polyimides and polymers with wholly aliphatic ether diamine links. Through dynamic mechanical analysis and differential scanning calorimetry, it is shown that control of the molar ratios of the aromatic MBDMA and the composition and size of the aliphatic polyetherdiamine can be used to tune the glass transition temperature. The materials were characterized and …


Evaluating Conversation Agent Impact On Student Experience In A Distance Education Course, Grover Walters Nov 2019

Evaluating Conversation Agent Impact On Student Experience In A Distance Education Course, Grover Walters

USF Tampa Graduate Theses and Dissertations

We explore the efficacy of conversation agents operating as an instructional aid in a distance education course. Two aspects of efficacy are considered—conversation agent impact on student perceptions of the experience, and how different design features of the agent affect student perceptions of engagement. Evaluation of the agent is accomplished by collecting data from 24 undergraduate participants separated into random groups. We conduct two rounds of mixedmethod evaluation. Between the two rounds, a modification to the agent occurs based on the outcome of the first evaluation. Findings include limitations related to phrasing and data persistence features of the design that …


Measuring And Utilizing High-Dimensional Information Of Optical Fields, Ziyi Zhu Nov 2019

Measuring And Utilizing High-Dimensional Information Of Optical Fields, Ziyi Zhu

USF Tampa Graduate Theses and Dissertations

Currently, many areas of optical techniques including imaging, inspection and communication emphasize the utilization of the high-dimensional information encoded in optical fields. There is also a requirement for novel measurement techniques to extract this high-dimensional information with high-speed and accuracy. We firstly introduce a scan-free direct measurement technique that is capable of simultaneously characterizing the amplitude and phase of a coherent scalar optical field. Our direct measurement approach is constituted of a weak polarization perturbation which is followed by the recording of a polarization-resolving imaging process. The weak perturbation rotates the linear polarization on the spatial frequency domain of the …


Experiences Of Using Intelligent Virtual Assistants By Visually Impaired Students In Online Higher Education, Michele R. Forbes Oct 2019

Experiences Of Using Intelligent Virtual Assistants By Visually Impaired Students In Online Higher Education, Michele R. Forbes

USF Tampa Graduate Theses and Dissertations

In today’s world, the attainment of higher education impacts the acquisition of competitive employment and, thus, quality of life. As a group, persons with disabilities continually fall behind others in such academic progress, requiring new efforts to support their earning of advanced credentials. Though highly beneficial for these individuals, obtaining a degree comes with elevated levels of stress. As enrollment of students with disabilities grows in all formats of higher education, those involved must understand the stress endured by these students and how to diminish it. Theories speculate that technology, such as intelligent virtual assistants, may be a viable tool …


Simulation And Software Development To Understand Interactions Of Guest Molecules Inporous Materials, Douglas M. Franz Jul 2019

Simulation And Software Development To Understand Interactions Of Guest Molecules Inporous Materials, Douglas M. Franz

USF Tampa Graduate Theses and Dissertations

The effect of inclusion of explicit polarization is investigated through several theoret- ical studies of crystalline porous materials herein. In addition to the use of Monte Carlo simulation for such studies, a robust molecular dynamics software is presented which is suitable for analyzing time dependent properties of gases or other molecules in porous materials and other condensed phase systems. Metal-organic frameworks (MOFs) are the main focus of the work included here, a relatively young class of materials originally in- troduced in the early 1990s. These are usually three dimensional crystalline nanoporous materials that exhibit unique properties such as gas separation, …


Towards Fundamental Understanding Of Thermoelectric Properties In Novel Materials Using First Principles Simulations, Artem R. Khabibullin Jun 2018

Towards Fundamental Understanding Of Thermoelectric Properties In Novel Materials Using First Principles Simulations, Artem R. Khabibullin

USF Tampa Graduate Theses and Dissertations

Thermoelectric materials play an important role in energy conversion as they represent environmentally safe and solid state devices with a great potential towards enhancing their efficiency. The ability to generate electric power in a reliable way without using non-renewable resources motivates many experimentalists as well as computational physicists to search and design new thermoelectric materials. Several classes of materials have been identified as good candidates for high efficient thermoelectrics because of their inherently low thermal conductivity. The complex study of the crystal and electronic structures of such materials helps to reveal hidden properties and give fundamental understanding, necessary for the …


Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall Apr 2018

Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall

USF Tampa Graduate Theses and Dissertations

Field learning is an important aspect of geoscience education to teach or reinforce concepts and skills, and the highly social experience of field work can improve learning outcomes, create networks to support future academic success, and promote a sense of belonging in the geosciences. However, field learning presents significant barriers to participation for students with physical disabilities. The introduction of digital data collection and communication devices into traditional field work settings has created new opportunities to expand access to field learning experiences such as remote collaboration; a method of undertaking field work through collaborative teamwork and the use of digital …


Coarse-Grained Modeling Studies Of Polymeric And Granular Systems, Hong Trung Nguyen Apr 2018

Coarse-Grained Modeling Studies Of Polymeric And Granular Systems, Hong Trung Nguyen

USF Tampa Graduate Theses and Dissertations

This Dissertation is devoted to computational study of the solidification, dynamics and mechanics of model semiflexible polymers with variable chain flexibility as well as a computational investigation of the clogging phenomena observed in granular materials.

Chain stiffness is an intrinsic factor that governs single-chain flexibility. It plays a critical role in the physics of polymeric materials. In this work, we employ a coarse-grained polymer model in which chain stiffness can be tuned by a single parameter (bending stiffness kb) that yields chain shape ranging from coil-like to rod-like in the flexible and very stiff limit respectively. In chapter 2, we …


Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele Apr 2018

Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele

USF Tampa Graduate Theses and Dissertations

High-nitrogen-content energetic compounds containing multiple N-N bonds are an attractive alternative towards developing new generation of environmentally friendly, and more powerful energetic materials. High-N content translates into much higher heat of formation resulting in much larger energy output, detonation pressure and velocity upon conversion to large amounts of non-toxic, strongly bonded N2 gas. This thesis describes recent advances in the computational discovery of group-I alkali and hydrogen polynitrogen materials at high pressures using powerful first-principles evolutionary crystal structure prediction methods. This is highlighted by the discovery of a new family of materials that consist of long-sought after all-nitrogen N􀀀 5 …


Application Of Metamaterials To Rf Energy Harvesting And Infrared Photodetection, Clayton M. Fowler Nov 2017

Application Of Metamaterials To Rf Energy Harvesting And Infrared Photodetection, Clayton M. Fowler

USF Tampa Graduate Theses and Dissertations

Techniques for adapting metamaterials for the improvement of RF energy harvesting and infrared photodetection are demonstrated using experimental and computer simulation methods. Two methods for RF energy harvesting are experimentally demonstrated and supported by computer simulation. In the first method, a metamaterial perfect absorber (MPA) is made into a rectenna capable of harvesting RF energy and delivering power to a load by soldering Schottky diodes onto connected split ring resonator (SRR) structures composing the planar metasurface of the perfect absorber. The metamaterial rectenna is accompanied by a ground plane placed parallel to it, which forms a Fabry-Perot cavity between the …


Surfaces And Epitaxial Films Of Corundum-Structured Mixed Metal Oxides., Alan Richard Kramer Nov 2017

Surfaces And Epitaxial Films Of Corundum-Structured Mixed Metal Oxides., Alan Richard Kramer

USF Tampa Graduate Theses and Dissertations

Throughout the last half century of materials science, significant motivations came from, and still do, the industrial applications of these materials. Whether it is electronic, thermal, tribological or chemical in nature, the study of metals, semiconductors and insulators eventually reveals that the surface plays a significant part in the properties of these materials. Understanding metal terminations reveals often that an oxide is the stable state of the metallic surface in an ambient atmosphere and the ability to predict and control these oxides has led to significant strides forward in not just the metallic bulk but the oxide as well.

Here …


Thermodynamic And Kinetic Aspects Of Hen Egg White Lysozyme Amyloid Assembly, Tatiana Miti Nov 2017

Thermodynamic And Kinetic Aspects Of Hen Egg White Lysozyme Amyloid Assembly, Tatiana Miti

USF Tampa Graduate Theses and Dissertations

Deposition of protein fibers with a characteristic cross-β sheet structure is the molecular marker associated with human disorders ranging from Alzheimer's disease to type II diabetes and spongiform encephalopathy. Given the large number of non-disease related proteins and peptides that have been shown to form amyloid fibrils in vitro, it has been suggested that amyloid fibril formation represents a generic protein phase transition. In the last two decades it has become clear that the same protein/peptide can assemble into distinct morphologically and structurally amyloid aggregates depending on the solution conditions. Moreover, recent studies have shown that the early stage, oligomeric …


Sustainable Development Through Urban Agriculture, Eric R. R. Weaver Mar 2017

Sustainable Development Through Urban Agriculture, Eric R. R. Weaver

USF Tampa Graduate Theses and Dissertations

This document includes three completed publications to represent Urban Agriculture as a ideal solution to meet the UN Sustainable Development Goals. The first publication (Weaver, 2017a) provided in Chapter Two examines the stormwater Best Management Practices (BMP) modelling parameters for the current EPA Stormwater Management Model (SWMM) as the first step to developing Urban Agriculture BMPs. The second publication (Weaver, 2015) provided in Chapter Three highlights how many high-rated scholars have identified agriculture as a critical driver for the planetary systems impacts we find with community development. The third publication (Weaver, 2017b) provided in Chapter Four breaks down a completely …


Development And Validation Of A Remote Sensing Model To Identify Anthropogenic Boreholes That Provide Dry Season, Refuge Habitat For Anopheles Vector Mosquitoes In Sub-Saharan Africa, James Pkemoi Kukat Jun 2016

Development And Validation Of A Remote Sensing Model To Identify Anthropogenic Boreholes That Provide Dry Season, Refuge Habitat For Anopheles Vector Mosquitoes In Sub-Saharan Africa, James Pkemoi Kukat

USF Tampa Graduate Theses and Dissertations

A lack of surveillance systems is an impediment to public health intervention for perennial vector-borne disease transmission in northern tropical savanna region of Kenya. The population in this area are mostly poor nomadic pastoralists with little acquired functional immunity to Plasmodium falciparum, due to infrequent challenges with the parasite. A common characteristic in tropical savanna climatic zone is the availability of riverbeds that have anthropogenic boreholes that provide malaria vector mosquitoes, such as Anopheles gambiae s.l and Anopheles funestus, with aquatic refuge habitats for proliferation and endemic transmission to proximity human households during the dry-season. Unfortunately, currently there …


Sound Attenuation Performance Of Fiber-Reinforced Polymer Composite Circumaural Hearing Protection Devices, Steven Christopher Augustine Jan 2015

Sound Attenuation Performance Of Fiber-Reinforced Polymer Composite Circumaural Hearing Protection Devices, Steven Christopher Augustine

USF Tampa Graduate Theses and Dissertations

Personnel who work on the flight deck of an aircraft carrier are exposed to extreme levels of jet engine noise often in excess of 140 decibels (dB). The current circumaural hearing protective devices (CAHPD) employed by flight deck crewmen are inadequate for the level of protection required for these extreme levels of noise. Fiber-reinforced thermoset polymer composite (FRPC) materials such as aramid fibers used in body armor, have high theoretical values of acoustic impedance due to a fundamentally high modulus of elasticity and may offer a superior level of hearing protection over original equipment (OE) thermoplastic CAHPDs. The objective of …


Algae: Opportunities For Biomass Feedstock Production, Wastewater Treatment And Educational Outreach, Trina Cassandra Halfhide May 2014

Algae: Opportunities For Biomass Feedstock Production, Wastewater Treatment And Educational Outreach, Trina Cassandra Halfhide

USF Tampa Graduate Theses and Dissertations

Algae are a diverse group of simple organisms that lack roots, stems or leaves and are able to use sunlight, carbon dioxide, and nutrients to produce complex compounds, such as carbohydrates, proteins and lipids. These compounds, especially lipids, are highly sought-after by agricultural, nutraceutical and energy interests. Although there is great potential for algae derived biofuels, there are technical and economic challenges associated with their cultivation. Relevant to this dissertation, the environmental impacts associated with algae cultivation can be reduced by using municipal and agricultural wastewaters as a water and nutrient source. This research was divided into three sections to …


Epibenthic Mobile Invertebrates Along The Florida Reef Tract: Diversity And Community Structure, Kristin Netchy Mar 2014

Epibenthic Mobile Invertebrates Along The Florida Reef Tract: Diversity And Community Structure, Kristin Netchy

USF Tampa Graduate Theses and Dissertations

Benthic mobile invertebrates are important components of coral-reef diversity and community structure, though, in most cases, their ecological contributions are poorly known. Baseline information on their diversity, prevalence, assemblages, and ecological roles is needed to aid in the conservation of coral-reef habitats. The objectives of this study are to 1) describe diversity and assemblages of epibenthic, mobile invertebrates in shallow water coral-reef communities in Florida, 2) evaluate their ecological roles by reviewing published literature on diet, and 3) measure the degree of linear dependence between mobile invertebrates and scleractinian corals. Underwater surveys were conducted in the summer of 2013 at …


Do Personality Tests Have A Place In Academic Preparation Of Undergradute Hospitality Students, Gunce Malan Jan 2013

Do Personality Tests Have A Place In Academic Preparation Of Undergradute Hospitality Students, Gunce Malan

USF Tampa Graduate Theses and Dissertations

This is a descriptive study that poses the questions and discussion regarding use of personality tests in prediction of future job performance of the current undergraduate hospitality students. A gap exists between the perception of the skills and competencies of high performers and the perception of hospitality students (Berezina et al., 2011; Malan, Berezina & Cobanoglu, 2012). The purpose of this study is to investigate if personality tests will help in predicting the success of students in their preferred job setting as compared to current high performers (managers).

The use of personality tests increased substantially after 1988, when the government …


Assessing Hurricane Preparedness Among Residential Staff At Louisiana State University: A Case Study On Hurricane Isaac, Ashley Marie Weatherall Jan 2013

Assessing Hurricane Preparedness Among Residential Staff At Louisiana State University: A Case Study On Hurricane Isaac, Ashley Marie Weatherall

USF Tampa Graduate Theses and Dissertations

Studying hurricane preparedness among the Resident Assistants (RAs) and Residence Life Coordinators (RLCs) at Louisiana State University (LSU) is imperative to assure that the university housing staff is fully equipped when faced with an oncoming threat. This study seeks to fill a gap in research by investigating the influences of preparedness on student housing employees. A survey was developed and the measures were found to be coherent and internally reliable through the use of factor analysis. Based on theory and previous literature, a linear regression model was developed that quantified the relationship between the independent variable of preparedness and general …