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Full-Text Articles in Engineering

Physical Electronic Properties Of Self-Assembled 2d And 3d Surface Mounted Metal-Organic Frameworks, Radwan Elzein Nov 2018

Physical Electronic Properties Of Self-Assembled 2d And 3d Surface Mounted Metal-Organic Frameworks, Radwan Elzein

USF Tampa Graduate Theses and Dissertations

Metal-organic frameworks stand at the frontiers of molecular electronic research because they combine desirable physical properties of organic and inorganic components. They are crystalline porous solids constructed by inorganic nodes coordinated to organic ligands to form 1D, 2D, or 3D structures. They possess unique characteristics such as ultrahigh surface area crystal lattices up to 10000 m2 g-1, and tunable nanoporous sizes ranging from 0.2 to 50 nm. Their unprecedented structural diversity and flexibility beyond solid state materials can lead to unique properties such as tailorable electronic and ionic conductivity which can serve as interesting platforms for a …


Pursuing Resilience Of Coastal Communities Through Sustainable And Integrated Urban Water Management, Pacia Díaz Nov 2018

Pursuing Resilience Of Coastal Communities Through Sustainable And Integrated Urban Water Management, Pacia Díaz

USF Tampa Graduate Theses and Dissertations

Reliability of water supply in the urban setting has become essential for communities to function and thrive. It is needed for more than mere human consumption and well-being. Although modern cities have water treatment and distribution systems, pressures from urbanization, population growth and the anticipated pressures of climate change are affecting the quality of water supply and the reliability of treatment and distribution systems. There is therefore an urgent need to take appropriate measures to improve the resilience of water supply systems before the impacts are irreversible.

Improving the resilience of water supply systems can be a challenge. In the …


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 Nov 2018

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 …


On The Feasibility Of Profiling, Forecasting And Authenticating Internet Usage Based On Privacy Preserving Netflow Logs, Soheil Sarmadi Nov 2018

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 Nov 2018

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 …


A Cost Benefit Analysis Of Using A Battery Energy Storage System (Bess) Represented By A Unit Commitment Model, Nemanja Mihailovic Nov 2018

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) …


Recovery Of Nutrients From Anaerobically Digested Enhanced Biological Phosphorus Removal (Ebpr) Sludge Through Struvite Precipitation, Maraida Balaguer-Barbosa Oct 2018

Recovery Of Nutrients From Anaerobically Digested Enhanced Biological Phosphorus Removal (Ebpr) Sludge Through Struvite Precipitation, Maraida Balaguer-Barbosa

USF Tampa Graduate Theses and Dissertations

Water resources in Florida have been severely degraded by eutrophic conditions, resulting toxic algae blooms, which negatively affect health and tourism. Eutrophication, or excessive amount of phosphorus (P) and nitrogen (N) in water, overstimulates the production of aquatic plants, depletes dissolved oxygen, and deteriorates the aquatic environment. However, phosphorus is a non-renewable resource essential for all living organisms. In fact, more than half of the total demand for P globally is to supply the food industry, which has concerningly accelerated the depletion rates of phosphate reserves.

In many wastewater treatment plants (WWTPs), the enhanced biological phosphorus removal (EBPR) approach has …


Validating The Accuracy Of Neatwork, A Rural Gravity Fed Water Distribution System Design Program, Using Field Data In The Comarca Ngöbe-Bugle, Panama, Maria Briones Jul 2018

Validating The Accuracy Of Neatwork, A Rural Gravity Fed Water Distribution System Design Program, Using Field Data In The Comarca Ngöbe-Bugle, Panama, Maria Briones

USF Tampa Graduate Theses and Dissertations

Despite the sustainable development goals to increase access to improved water there are still 884 million people in the world without access to an improved water source (WHO, 2017). One method to improve access to water in rural, mountainous areas, is through construction of gravity fed water distribution systems. These systems should be designed based upon fundamental principles of hydraulics. One method of doing so in a time efficient manner with minimal engineering knowledge is to utilize a downloadable computer program such as Neatwork, which aids in design of rural, gravity fed water distribution systems and has been used by …


Forewarned Is Forearmed: Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World By Timothy H. Dixon (2017), Jason Makansi Jul 2018

Forewarned Is Forearmed: Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World By Timothy H. Dixon (2017), Jason Makansi

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

Curbing Catastrophe for the most part lives up to what is claimed in the foreword: “…a compelling account of recent and historical disasters, both natural and human-caused, drawing on common themes and providing a holistic understanding of hazards, disasters, and mitigation for anyone interested in this important and topical subject.” This is a pretty thorough treatment of an extraordinarily complex subject, and the gaps identified in this review should be considered explications more than …


The Effect Of Processing Conditions On The Energetic Diagram Of Cdte Thin Films Studied By Photoluminescence, Shamara P. Collins Jul 2018

The Effect Of Processing Conditions On The Energetic Diagram Of Cdte Thin Films Studied By Photoluminescence, Shamara P. Collins

USF Tampa Graduate Theses and Dissertations

The photovoltaic properties of CdTe-based thin films depend on recombination levels formed in the CdTe layer and at the heterojunction. The localized states are resultant of structural defects (metal sublattice, chalcogen sublattice, interstitial), controlled doping, deposition process, and/or post-deposition annealing. The photoluminescence study of CdTe thin films, from both the bulk and heterojunction, can reveal radiative states due to different defects or impurities. Identification of defects allows for potential explanation of their roles and influence on solar cell performance. A thorough understanding of the material properties responsible for solar cell performance is critical in further advancing the efficiency of devices. …


A Quantitative Analysis Of Shape Characteristics Of Marine Snow Particles With Interactive Visualization: Validation Of Assumptions In Coagulation Models, Palak P. Dave Jun 2018

A Quantitative Analysis Of Shape Characteristics Of Marine Snow Particles With Interactive Visualization: Validation Of Assumptions In Coagulation Models, Palak P. Dave

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon oil spill that started on April 20, 2010, in the Gulf of Mexico was the largest marine oil spill in the history of the petroleum industry. There was an unexpected and prolonged sedimentation event of oil-associated marine snow to the seafloor due to the oil spill. The sedimentation event occurred because of the coagulation process among oil associated marine particles. Marine scientists are developing models for the coagulation process of marine particles and oil, in order to estimate the amount of oil that may reach the seafloor along with marine particles. These models, used certain assumptions regarding …


Channel Camouflage And Manipulation Techniques In Wireless Networks, Song Fang Jun 2018

Channel Camouflage And Manipulation Techniques In Wireless Networks, Song Fang

USF Tampa Graduate Theses and Dissertations

The security of wireless networks and systems is becoming increasingly important as wireless devices are more and more ubiquitous nowadays. The wireless channel exhibits the spatial uncorrelation property, which is that the characteristics of a wireless channel become uncorrelated every half carrier wavelength over distance. This property has prompted an emerging research area that utilizes wireless channel characteristics to achieve location distinction, to detect location changes or facilitate authentication of wireless users, and to establish shared secret key between legitimate communicators. This dissertation includes two work toward the security improvement of existing wireless networks and systems. With the discovered channel …


Sustainable Production Of Bio-Based Succinic Acid From Plant Biomass, Enlin Lo Jun 2018

Sustainable Production Of Bio-Based Succinic Acid From Plant Biomass, Enlin Lo

USF Tampa Graduate Theses and Dissertations

Succinic acid is a compound used for manufacturing lacquers, resins, and other coating chemicals. It is also used in the food and beverage industry as a flavor additive. It is predominantly manufactured from petrochemicals, but it can also be produced more sustainably by fermentation of sugars from renewable feedstocks (biomass). Bio-based succinic acid has excellent potential for becoming a platform chemical (building block) for commodity and high-value chemicals.

In this study, we focused on the production of bio-based succinic acid from the fiber of sweet sorghum (SS), which has a high fermentable sugar content and can be cultivated in a …


Underground Stormwater Treatment Performance In Urban Coastal Catchments: Case Study Of Baffle Boxes In The City Of Tampa, Awet Eyob Tsegay Jun 2018

Underground Stormwater Treatment Performance In Urban Coastal Catchments: Case Study Of Baffle Boxes In The City Of Tampa, Awet Eyob Tsegay

USF Tampa Graduate Theses and Dissertations

In coastal urban regions, underground stormwater treatment units are suitable infrastructure options because they take less space where premium land is expensive. Even then, they should be accessible and ideally small enough to fit into existing stormwater networks. Since 2003, the City of Tampa and Florida’s Department of Transportation (FDOT) have installed 47 baffle boxes into the city’s stormwater pipe networks. Baffle boxes are underground stormwater treatment structures designed to capture sediments and floating debris. Since their deployment, many challenges regarding their practical sediment capturing performance was raised by the city.

The objective of this research was to evaluate the …


Regulatory Methodology And Unmitigated Wetland Loss In Southwest Florida, Kathleen B. Castor Jun 2018

Regulatory Methodology And Unmitigated Wetland Loss In Southwest Florida, Kathleen B. Castor

USF Tampa Graduate Theses and Dissertations

This research used Geographical Information System (GIS) data to estimate the acreage of wetland loss due to small-scale activities (taking into account exempt, permitted, and unauthorized activities) in the Southwest District of the Department of Environmental Protection (DEP) between 2006 and 2011 and compared that net loss with the unmitigated wetland net loss that DEP documented during that time for authorized activities and violations that were discovered. The comparison allowed an estimation of the extent of undocumented small-scale unmitigated wetland loss that occurred during those six years. DEP records show that 88% of non-compliance cases remain unresolved, and the net …


Dynamic Modeling Of An Advanced Wastewater Treatment Plant, Komal Rathore Jun 2018

Dynamic Modeling Of An Advanced Wastewater Treatment Plant, Komal Rathore

USF Tampa Graduate Theses and Dissertations

Advanced wastewater treatment plants have complex biological kinetics, time variant influent rates and long processing times. The modeling and operation control of wastewater treatment plant gets complicated due to these characteristics. However, a robust operational system for a wastewater treatment plant is necessary to increase the efficiency of the plant, reduce energy cost and achieve environmental discharge limits. These discharge limits are set by the National Pollutant Discharge Elimination System (NPDES) for municipal and industrial wastewater treatment plants to limit the amount of nutrients being discharged into the aquatic systems.

This document summarizes the research to develop a supervisory operational …


Emerging Non-Volatile Memory Technologies For Computing And Security, Rekha Govindaraj May 2018

Emerging Non-Volatile Memory Technologies For Computing And Security, Rekha Govindaraj

USF Tampa Graduate Theses and Dissertations

With CMOS technology scaling reaching its limitations rigorous research of alternate and competent technologies is paramount to push the boundaries of computing. Spintronic and resistive memories have proven to be effective alternatives in terms of area, power and performance to CMOS because of their non-volatility, ability for logic computing and easy integration with CMOS. However, deeper investigations to understand their physical phenomenon and improve their properties such as writability, stability, reliability, endurance, uniformity with minimal device-device variations is necessary for deployment as memories in commercial applications. Application of these technologies beyond memory and logic are investigated in this thesis i.e. …


Characterization Of Computed Tomography Radiomic Features Using Texture Phantoms, Muhammad Shafiq Ul Hassan Apr 2018

Characterization Of Computed Tomography Radiomic Features Using Texture Phantoms, Muhammad Shafiq Ul Hassan

USF Tampa Graduate Theses and Dissertations

Radiomics treats images as quantitative data and promises to improve cancer prediction in radiology and therapy response assessment in radiation oncology. However, there are a number of fundamental problems that need to be solved in order to potentially apply radiomic features in clinic. The first basic step in computed tomography (CT) radiomic analysis is the acquisition of images using selectable image acquisition and reconstruction parameters. Radiomic features have shown large variability due to variation of these parameters. Therefore, it is important to develop methods to address these variability issues in radiomic features due to each CT parameter. To this end, …


Elastin-Like Polypeptide Fusion Tag As A Protein-Dependent Solubility Enhancer Of Cysteine-Knot Growth Factors, Tamina L. Johnson Apr 2018

Elastin-Like Polypeptide Fusion Tag As A Protein-Dependent Solubility Enhancer Of Cysteine-Knot Growth Factors, Tamina L. Johnson

USF Tampa Graduate Theses and Dissertations

Elastin-like peptide (ELP) fusions promote therapeutic delivery and efficacy. Recombinant proteins, like neurotrophins, lack bioavailability, have short in vivo half-lives, and require high manufacturing costs. Fusing recombinant proteins with genetically encodable ELPs will increase bioavailability, enhance in vivo solubilization, as well as provide a cost-effective method for purification without the need for chromatography. During expression of neurotrophin-ELP (N-ELP) fusions, dense water-insoluble aggregates known as inclusion bodies (IBs) are formed. Inclusion bodies are partially and misfolded proteins that usually require denaturants like Urea for solubilization. Strong denaturants arrest ELPs stimuli-responsive property and increase unwanted aggregation, making purification difficult, yet possible. The …


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 …


In Situ Extrinsic Doping Of Cdte Thin Films For Photovoltaic Applications, Imran Suhrid Khan Mar 2018

In Situ Extrinsic Doping Of Cdte Thin Films For Photovoltaic Applications, Imran Suhrid Khan

USF Tampa Graduate Theses and Dissertations

The Cadmium Telluride thin film solar cell is one of the leading photovoltaic technologies. Efficiency improvements in the past decade made it a very attractive and practical source of renewable energy. Considering the theoretical limit, there is still room for improvement, especially the cell’s open circuit voltage (VOC). To improve VOC, the p-type carrier concentration and minority carrier lifetime of the CdTe absorber needs to be improved. Both these parameters are directly related to the point defect distribution of the semiconductor, which is a function of deposition stoichiometry, dopant incorporation and post-deposition treatments.

CdTe films were deposited by the Elemental …


Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca Mar 2018

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 …


Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare Mar 2018

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 La0.75Sr0.25FeO3 (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 Mar 2018

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 …


Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones Mar 2018

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. …


Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou Jan 2018

Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou

USF Tampa Graduate Theses and Dissertations

Climate change is a global concern as it may affect many aspects of life, including water supply. A tool used to model climate change’s impacts is called a General Circulation Model (GCM). GCMs project future scenarios including temperature and precipitation, but these are designed at a coarse resolution and require downscaling for employment for regional hydrologic modeling. There is a vast amount of research on downscaling and bias-correcting GCMs data, but it is unknown whether these techniques alter precipitation signals embedded in these models or reproduce climate states that are viable for water resource planning and management. Using the Tampa, …