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Sorbent Enrichment Performance Of Aromatic Compounds From Diluted Liquid Solution, Le Meng

USF Tampa Graduate Theses and Dissertations

Sorbent enrichment is treated as the extend sample preparing method from liquid extraction. The theories of liquid extraction also extend to sorbent enrichment, which is based on the distribution equilibrium. With the development of advanced materials, sorbents have been improved dramatically in the past twenty years. Nowadays, more and more enrichment performance cannot be explained from the angle of distribution model.

Herein, the sorption model is emphasized in this study. As the majority exist, aromatic compounds are the focused class of analytes. This study analyzed the sorption from two factors, the interaction between adsorbate and sorbent from their aromaticity, and …

Assessing The Cooling Effects Of Urban Vegetation On Urban Heat Mitigation In Selected U.S. Cities, Qiuyan Yu

USF Tampa Graduate Theses and Dissertations

Urban Heat Island (UHI) is a growing problem worldwide. Mitigation of UHI is necessary for cities to adapt to climate change and enhance sustainable development at a city scale. Cooling cities with urban vegetation management is a sustainable solution for urban heat mitigation. Urban vegetation influences urban microclimate through the shading effect, surface roughness, and evapotranspiration. The differences in horizontal and vertical structures of urban vegetation determine the shading effect, surface roughness, and evapotranspiration. Enhancing the cooling effect of urban vegetation requires a comprehensive understanding of how vegetation structure affects UHI. The effects of horizontal structure on land surface temperature …

Exploring The ‘Spaces Between’: Teachers’ Perceptions Of Teacher Leadership Within Professional Networks, Cynthia B. Bauman

USF Tampa Graduate Theses and Dissertations

The enactment of teacher leadership can be challenged by both policy initiatives and school contexts (Anderson & Cohen, 2015; Hargreaves & Fullan, 2012). However, teachers can have a positive influence on each other and their broader school community by building capacity for leadership, innovation, and student achievement through the relationships, or networks, they develop and maintain (Baker-Doyle, 2015; Hovardas, 2016; Hunzicker, 2012; Moolenaar, Sleegers, & Daly, 2012). This single exploratory case study takes place in a Title I elementary school and uses a combination of Social Network Analysis and content analysis to uncover patterns in teacher professional networks, the context …

Perceived Roles Of Academic Advisors In Pursuing Internationalization At Public State And Community Colleges In Florida, Tony W. Long

USF Tampa Graduate Theses and Dissertations

This research study investigated the perceptions of academic advisors in the Florida College System (FCS) concerning globalization, internationalization, and their role in the process of internationalizing their colleges. Participants in the study included 54 academic advisors from 15 of the 28 colleges in the FCS. The sample was comprised primarily of female advisors with master’s degrees, who had been working in higher education for less than 13 years. This was a nonexperimental, quantitative study and analyses included descriptive statistics, ordinary least squares regression, and Pearson’s product moment correlations.

The results revealed that the responding advisors believe that globalization is inevitable …

Flowgraph Models For Clustered Multistate Time To Event Data, Kristin Hall

USF Tampa Graduate Theses and Dissertations

Healthcare systems have multistate processes. Such processes may be modeled using flowgraphs, which are directed graphs. Flowgraph models support a variety of transition time distributions, easily handle reversibility between states and allow alternate paths to the event or state of interest to be taken. However, estimation of flowgraph and first passage time distribution parameters can lead to incorrect inferences when interdependent data are treated as independent.

In this dissertation, we expand the flowgraph model to accommodate nested and correlated data structures. We develop a framework to incorporate random effects into transition probability and transition time components of a flowgraph model. …

Optical Remote Sensing Of Oil Spills In The Gulf Of Mexico, Shaojie Sun

USF Tampa Graduate Theses and Dissertations

Assessment of oil spills in the ocean using passive remote sensing (i.e., reflected sun light) faces two challenges: detect oil presence/absence and quantify oil volume. While the optical properties of oil allow it to be differentiated from the surrounding marine environment, sun glint can facilitate oil presence/absence detection because the oil-water spatial contrast is enhanced due to wave dampening. However, sun glint also modulates the magnitude and shape of the spectral reflectance of surface oil. In addition to this difficulty, the most critical challenge is how to quantify oil volume (or thickness) through remote sensing. To date, such quantifications have …

Enhancement Of Rainfall-Triggered Shallow Landslide Hazard Assessment At Regional And Site Scales Using Remote Sensing And Slope Stability Analysis Coupled With Infiltration Modeling, Thilanki Maneesha Dahigamuwa Rajaguru Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Landslides cause significant damage to property and human lives throughout the world. Rainfall is the most common triggering factor for the occurrence of landslides. This dissertation presents two novel methodologies for assessment of rainfall-triggered shallow landslide hazard. The first method focuses on using remotely sensed soil moisture and soil surface properties in developing a framework for real-time regional scale landslide hazard assessment while the second method is a deterministic approach to landslide hazard assessment of the specific sites identified during first assessment. In the latter approach, landslide inducing transient seepage in soil during rainfall and its effect on slope stability …

Wastewater In Context: Systems-Based Approaches To Improving Wastewater Infrastructure Transitions, Christine Prouty

USF Tampa Graduate Theses and Dissertations

Coastal communities and ecosystems around the world are some of those most vulnerable to the impacts of climate change. In particular, the wastewater treatment systems in these areas are on the forefront of the effects of increasing frequency, duration, and intensity associated with extreme weather events. As such, decision making about adopting new wastewater technologies or transitioning to an improved treatment portfolio is an important area of research for coastal communities because they are critically linked to the health of the nearby aquatic ecosystems (i.e. tourism, fishing, cultural heritage, climate protection).

The decision making process about technology adoption and transitions …

Aqueous Humor Dynamics And The Constant-Pressure Perfusion Model Of Experimental Glaucoma In Brown-Norway Rats, Kayla R. Ficarrotta

USF Tampa Graduate Theses and Dissertations

Glaucoma affects tens of millions of people and is the leading cause of irreversible blindness worldwide. Virtually all current glaucoma therapies target elevated intraocular pressure (IOP); however, the contribution of intracranial pressure (ICP) to glaucoma has recently garnered interest. Strain at the optic nerve head is now known to depend on the translaminar pressure difference (TLPD), which is the difference between IOP and ICP, rather than IOP alone. A better understanding of how IOP and ICP relate to glaucoma development and progression is essential for developing improved therapies and diagnostic tests. Glaucoma is commonly modeled in rats, yet aqueous humor …

Students’ Opportunity To Learn Surface Area And Volume In Middle Grades Mathematics Textbooks, Sofia Hatziminadakis

USF Tampa Graduate Theses and Dissertations

I conducted a content analysis to examine the treatment of the surface area and volume concepts within four published middle-grades mathematics textbook series. In particular, I examined the treatment of the surface area and volume concepts in terms of the location of surface area and volume lessons in the textbook and the number of pages and lessons devoted to these concepts. I also investigated the sequence of the instructional blocks of surface area and volume lessons. In addition, I evaluated the tasks included in these lessons in regards to the performance expectations of students, the types of visual representations of …

Multilayer Dielectric Rod Waveguide And Dielectric Rod Antenna With Enhanced Performance, Denise C. Lugo

USF Tampa Graduate Theses and Dissertations

This dissertation presents first a comprehensive study of the design and performance of a multilayer dielectric rod waveguide (DRW) with rectangular cross-section. The design is comprised of a high permittivity core encased by a low permittivity cladding. A modal analysis of the multilayer DRW with a 2:1 core aspect ratio is presented and a mathematical model is proposed to characterize the fundamental mode cutoff frequency in terms of the core and cladding permittivity and the core dimensions. The explicit nature of the model is useful for design and it offers an excellent match to the full-wave EM simulation data. The …

A Secure Computing Platform For Building Automation Using Microkernel-Based Operating Systems, Xiaolong Wang

USF Tampa Graduate Theses and Dissertations

Building Automation System (BAS) is a complex distributed control system that is widely deployed in commercial, residential, industrial buildings for monitoring and controlling mechanical/electrical equipment. Through increasing industrial and technological advances, the control components of BAS are becoming increasingly interconnected. Along with potential benefits, integration also introduces new attack vectors, which tremendous increases safety and security risks in the control system. Historically, BAS lacks security design and relies on physical isolation and "security through obscurity". These methods are unacceptable with the "smart building" technologies. The industry needs to reevaluate the safety and security of the current building automation system, and …

Enhancing The Design Of A Cybersecurity Risk Management Solution For Communities Of Trust, James E. Fulford Jr.

USF Tampa Graduate Theses and Dissertations

Research into cybersecurity risks and various methods of evaluating those threats has become an increasingly important area of academic and practitioner investigations. Of particular interest in this field is enhancing the designs and informing capabilities of cybersecurity risk management solutions for users who desire to understand how organizations are impacted when such risks are exploited. Many of the cybersecurity risk management solutions are extremely technical and require their users to have a commensurate level of technical acumen. In the situation evaluated during this research project, the founders of the company being researched had created a highly technical risk management solution …

Structure-Based Design, Synthesis And Applications Of A New Class Of Peptidomimetics: 'Y-Aa Peptides And Their Derivatives, Ma Su

USF Tampa Graduate Theses and Dissertations

Peptidomimetics can mimic hierarchical structures of peptides and proteins. Thus, they are extensively studied for therapeutic applications. To break the limitation of backbones and frameworks and expand the peptidomimetics family, a new class of peptidomimetics - “γ-AApeptides” was developed. Design of γ-AApeptides is based on the chiral peptide nucleic acids (PNAs) backbone.

The World Health Organization estimates that one -third of all deaths in the world are on account of infectious diseases. AMPs are important because of their high activity against broad spectrum microbes, less susceptible to grow resistance and selectivity in binding to bacterial cells over human cells. γ-AApeptides …

Simulation And Optimization Of A Sheathless Size-Based Acoustic Particle Separator, Shivaraman Asoda

USF Tampa Graduate Theses and Dissertations

Standing surface acoustic waves (SSAW) have been widely used for sorting of cells and particles. However, the major challenges faced with the acoustic driven separation process is the need for an optimized setup to achieve effective separation and the range of particles that can be separated. In this thesis, a custom simulation model is studied to investigate and optimize the separation of varying size particles in a sheathless acoustic separation platform that was developed in our research lab. Specifically, the effect of flowrate, pressure amplitude, wavelength and interdigitated transducers (IDTs) physical parameters on the separation efficiency is explored. We also …

Development Of A New Piezoelectric-Based Energy Harvesting Pavement System, Lukai Guo

USF Tampa Graduate Theses and Dissertations

A novel design of a piezoelectric-based energy harvesting pavement system (PZ-EHPS) is introduced in this dissertation work. The design concept of this PZ-EHPS is to transform asphalt layers into a piezoelectric energy harvester to collect dissipated vehicle kinetic energy in a large-scale system, relying on two conductive asphalt layers and one piezoelectric material layer. To verify the feasibility of the above design concept, this dissertation work practically fabricated and tested a series of PZ-EHPS specimens under the loads from a Material Testing System (MTS) in the laboratory, and theoretically analyzed one typical PZ-EHPS specimen via a three-degree-of-freedom electromechanical model and …

Control Of Uncertain Dynamical Systems With Spatial And Temporal Constraints, Ehsan Arabi

USF Tampa Graduate Theses and Dissertations

The overarching objective of this dissertation is the development of feedback control frameworks for uncertain dynamical systems that are subject to spatial and/or temporal constraints. These spatiotemporal constraints usually arise from the physical and/or performance characteristics associated with a considered dynamical system in safety-critical applications, where synthesis and analysis of feedback control laws are not trivial. Specifically, the proposed control architectures in this dissertation mainly contribute to the model reference adaptive control and finite-time control literature. In particular, unlike existing model reference adaptive control approaches that are not capable of enforcing user-defined performance guarantees without an ad-hoc tuning process, the …

On The Feasibility Of Profiling, Forecasting And Authenticating Internet Usage Based On Privacy Preserving Netflow Logs, Soheil Sarmadi

USF Tampa Graduate Theses and Dissertations

Understanding Internet user behavior and Internet usage patterns is fundamental in developing future access networks and services that meet technical as well as Internet user needs. User behavior is routinely studied and measured, but with different methods depending on the research discipline of the investigator, and these disciplines rarely cross. We tackle this challenge by developing frameworks that the Internet usage statistics used as the main features in understanding Internet user behaviors, with the purpose of finding a complete picture of the user behavior and working towards a unified analysis methodology. In this dissertation we collected Internet usage statistics via …

An Analytical Solution For Attainment Of Field Capacity, Ali Aldrees

USF Tampa Graduate Theses and Dissertations

Field Capacity (FC) is a key parameter to quantify in agricultural engineering, irrigation controlling, and soil physics studies. For instance, irrigation studies focuses on determining the optimal amount of water needed by plants to grow following an irrigation system and therefore relies on determining FC. Likewise, the value of FC is a good indicator of soil textures, structures and pore size distributions. For example, loamy soils have a wider distribution of pores leading to high FC values. FC depends on multiple physically-grounded variables which include matric potential value (ψ_FC ), water content at FC (θ_FC ), specific drainage time to …

Lump Solutions And Riemann-Hilbert Approach To Soliton Equations, Sumayah A. Batwa

USF Tampa Graduate Theses and Dissertations

In the first part of this dissertation we introduce two matrix iso-spectral problems, a Kaup-Newell type and a generalization of the Dirac spectral problem, associated with the three-dimensional real Lie algebras sl(2;R) and so(3;R), respectively. Through zero curvature equations, we furnish two soliton hierarchies. Hamiltonian structures for the resulting hierarchies are formulated by adopting

the trace identity. In addition, we prove that each of the soliton hierarchies has a bi-Hamiltonian structure which leads to the integrability in the Liouville sense. The motivation of the first part is to construct soliton hierarchies with infinitely many commuting symmetries and conservation laws.

The …

Quantifying The Probability Of Lethal Injury To Florida Manatees Given Characteristics Of Collision Events., B. Lynn Combs

USF Tampa Graduate Theses and Dissertations

Wherever wildlife share space with boaters, collisions are a potential source of mortality. Establishing protection and speed zones are the primary actions taken to mitigate collision risk. However, creation of protection zones may be a point of contention with stakeholders as new zones can have significant socioeconomic impacts. The Florida Manatee is a prime example of a species whose abundance and viability are constrained by this balance between the needs of humans and wildlife on a shared landscape. The goal of this work is to help further understand the risk to manatees by quantifying the probability of lethal collisions. I …

Evaluating The Use Of Larval Connectivity Information In Fisheries Models And Management In The Gulf Of Mexico, Michael Drexler

USF Tampa Graduate Theses and Dissertations

Connectivity is a major contributor to the overall dynamics of marine populations. However, it still remains challenging to describe connectivity on ecologically meaningful scales of time and space. This is a major impediment to evaluating the impacts of marine protected area with respect to fisheries management objectives.

This dissertation brings together a wide array of spatial and connectivity information in the Gulf of Mexico (GOM) with the goal of 1) understanding the spatial distribution of fish populations and source-sink dynamics and 2) evaluating whether this information can be integrated, through a modeling framework, to identify closed areas that could be …

A Cost Benefit Analysis Of Using A Battery Energy Storage System (Bess) Represented By A Unit Commitment Model, Nemanja Mihailovic

USF Tampa Graduate Theses and Dissertations

This thesis aims to provide a general overview of a cost and benefit analysis of incorporating a battery energy storage system within unit commitment model.

The deregulation of the electricity market in the U.S. has only been around for the last two decades. With renewable energy and energy storage systems becoming less expensive, a decentralized market scheme is becoming more popular and plausible. The scope of this work is to provide a fundamental understanding of unit commitment and a cost analysis of applying a battery energy storage system to an already established power system.

A battery energy storage system (BESS) …

You’Re Not Helping: Unhelpful Workplace Social Support As A Job Stressor, Cheryl E. Gray

USF Tampa Graduate Theses and Dissertations

While support is generally a helpful resource for employees, support can also serve as a job stressor. Unhelpful workplace social support (UWSS) is any action taken by a supervisor and/or colleague that is intended to benefit another worker but is perceived as unhelpful or harmful by the recipient. A series of three studies identified types of UWSS, developed a measure of UWSS, and established a nomological network of variables related to UWSS. In Study 1, critical incidents were collected from 116 employees, and a content analysis revealed 11 distinct categories of UWSS. A measure of UWSS was developed in Study …

Testing The Validity And Utility Of A Career And Technical Education Programs Of Study Evaluation Instrument, Alisha D. Hyslop

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to build on the research already completed by the Association for Career and Technical Education (ACTE) in the development of ACTE’s quality Program of Study Framework and accompanying evaluation instrument to examine the validity of the instrument’s results and its utility when used independently by local educators in a pilot test. The study used a two-phase mixed-methods design. In the first phase, 39 participating programs were evaluated using the instrument, consisting of 102 items organized into 12 elements. Representatives of participating programs, either teachers or administrators, then provided quantitative and qualitative feedback about the …

Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich

USF Tampa Graduate Theses and Dissertations

Using a towed underwater video camera system, benthic habitats were classified along transects in a popular offshore fishing area on the West Florida Shelf (WFS) known as “The Elbow.” Additionally, high resolution multibeam bathymetry and co-registered backscatter data were collected for the entire study area. Using these data, full coverage geologic and biotic habitat maps were developed using both unsupervised and supervised statistical classification methodologies. The unsupervised methodology used was k-means clustering, and the supervised methodology used a random forest algorithm. The two methods produced broadly similar results; however, the supervised methodology outperformed the unsupervised methodology. The results of the …

Harnessing Social Norms To Increase Men's Interest In Heed Careers, Joanna R. Lawler

USF Tampa Graduate Theses and Dissertations

Men’s underrepresentation in the female-dominated domains of healthcare, early education, and the domestic sphere, or HEED roles, remains a persistent problem despite the fact that such careers often afford more job security and wage growth than blue-collar work. A growing body of evidence suggests that their lack of participation in HEED roles is not merely due to a skills mismatch, but rather an identity mismatch. I hypothesized that using descriptive and injunctive norms to reframe a stereotypically feminine career as more compatible with manhood could effectively reduce this identity mismatch. More specifically, I predicted that using a dynamic descriptive norm …

Analysis And New Applications Of Metal Organic Frameworks (Mof): Thermal Conductivity Of A Perovskite-Type Mof And Incorporation Of A Lewis Pair Into A Mof., Wilarachchige D C B Gunatilleke

USF Tampa Graduate Theses and Dissertations

Metal organic frameworks have gained much attention due to their tunable pore sizes and very high surface areas. With the discovery many of these type materials the need has raised to look into new applications of theses porous frameworks. This thesis focuses on the synthesis of a new perovskite-type metal organic framework and measurement of its thermal conductivity in search of its applicability as a thermoelectric material. The second part of this work focuses on the synthesis of a metal organic framework incorporated with a Lewis pair for the first time. The optimum loading amount of the Lewis pair into …

Acoustic Source Localization With A Vtol Suav Deployable Module, Kory Olney

USF Tampa Graduate Theses and Dissertations

A real time acoustic direction-finding module has been developed to estimate the ele- vation and azimuth of an impulsive event while function aboard a small unmanned air- craft vehicle. The generalized cross-correlation with phase transform method was used to estimate time differences of arrival in an 8 channel microphone array. A linear least squares approach was used to calculate an estimate for the direction of arrival. In order to accomplish this task, a vertical takeoff and landing small unmanned aircraft system was assembled to host the direction finding module. The module itself is made up of an eight-channel synchronous analog-to-digital …

Comparison Of Modeled And Measured Pesticide Concentrations In Air, Trenell Davis Boggans

USF Tampa Graduate Theses and Dissertations

Chlorpyrifos (CPF) is a popular organophosphorus insecticide that is heavily used in the agriculture industry as a means of pest control. Chlorpyrifos is known for its toxic effect to inhibit the enzyme acetylcholinesterase (ACHE) in humans and is widely used in areas of California where the site of application is close to occupied areas, such that exposures to residents and bystanders can occur due to secondary drift. Secondary drift refers to the volatilization of a pesticide from the surface to which it was applied (e.g. soil or plant foliage) and subsequent off-site movement in ambient air. Secondary drift is different …