Digital Commons Network^™

Perceptions Of The Effectiveness Of Food Policy Coalitions In Strengthening Community Food Security In The United States., Joseph G. England Iii

USF Tampa Graduate Theses and Dissertations

Food insecurity is experienced most acutely and addressed most innovatively at the community level to which the concept of community food security (CFS) finds purchase (Hamm and Bellows, 2003). In recognition of the many varying dynamics embedded in the CFS concept, Food Policy Coalitions have become an organizational model adapted by communities across the United States. While FPCs have grown in number considerably over the last decade, there remains a considerable lack of empirical research documenting evaluation and engagement methods, as well as strategies used to address community food security. This research, framed by the Community Coalition Action Theory, draws …

Desertification Risk Analysis Based On Soils And Climate In Olive Cultivated Areas In Tulare County, California, Zehra Kavakli Karatas

USF Tampa Graduate Theses and Dissertations

Desertification is one of the most critical environmental problems caused by human activities and climate change. As a result of human activities, land degradation has been seen in many agricultural areas. Intense pressure on cultivated fields causes loss of soil fertility, which can then lead to desertification. Planting plant drought-resistant plants, such as olives, is one strategy for reducing desertification risk in cultivated areas. It is essential to find a way not only how to combat this process but also how to adapt or survive with desertification conditions. Defining desertification risks have a fundamental role in combating drought. The goal …

Fabrication And Characterization Of Electrical Energy Storage And Harvesting Energy Devices Using Gel Electrolytes, Belqasem Aljafari

USF Tampa Graduate Theses and Dissertations

Redox-active materials in the bulk of gel electrolytes are unquestionably holding the primary roles in developing energy harvesting and storage technology. Both technologies are necessary in order to cope with the current challenges of the environmental crises of global warming and finite non-renewable sources while the demand for energy modern societies have been speedily increased. One of the most challenges of making a hybrid device of energy conversion and storage is the cost of the fabrication process. Therefore, gel electrolyte-based materials with redox-active properties can potentially be a promising solution to improve the performance of electrochemical and photoelectrochemical devices for …

Fewer Wetlands More Connectivity: Implications Of Land Use-Land Cover Change In An Agricultural Landscape, Stephanie Lawlor

USF Tampa Graduate Theses and Dissertations

St. Lucie County (SLC) is a 1,782 km2 area in east-central Florida that drains to the Nationally Significant Indian River Lagoon (IRL). It is low lying and nearly level, with widespread non-floodplain wetlands (NFWs) and few natural channels. NFWs comprise the vast majority of SLC wetlands, both in terms of numbers and area. Since the early 20th century, SLC has undergone extensive land use-land cover (LULC) change and is now characterized by citrus farming in the interior and municipalities on its eastern coast on the Atlantic Ocean. This LULC change has been made possible by the construction of an extensive …

Energy Transition Modeling: Social And Technical Dynamics Of Moving To Renewable Energy, Lawrence Gottschamer

USF Tampa Graduate Theses and Dissertations

The majority of global electricity is generated using fossil fuels as an energy source, and the science linking fossil fuel combustion with negative environmental impacts is clear. Recognizing this link, decarbonizing the electricity system is a critical component of climate change mitigation. However, moving electricity generation, distribution, and end-use behavior patterns to renewable energy is a complex socio-technical energy transition challenge with a number of economic, policy, technological, societal and environmental barriers. Energy transition work tends to be siloed within these topics; ignoring complex socio-technical interdependencies impacting electricity system transition dynamics. This work fills the knowledge gap with a ‘systems …

Sundaas Story: A Mixed-Methods Study Of Household Sanitation Provisioning In Urban Informal Housing In India, Sarita Vijay Panchang

USF Tampa Graduate Theses and Dissertations

The aims of this research were to examine sanitation insecurity in urban informal housing through the lens of the built environment, social disparities, and health implications. While the Millennium Development Goals for halving the global proportion of people without access to safe drinking water were met ahead of schedule, progress fell short for sanitation, creating new objectives for the Sustainable Development Goals to be met in 2030. Much research in the Global South is dedicated to community-level sanitation promotion, but often presumes a rural rather than urban setting. Urban informal housing settings constitute a unique challenge due to the range …

Modeling Of Buildings With Electrochromic Windows And Thermochromic Roofs, Hua-Ting Kao

USF Tampa Graduate Theses and Dissertations

Air conditioning and heating have increased substantially during the past two decades. According to a survey, buildings consume about 73% of the total electricity in the United States, accounting for 41% of all other energy in the world. At the same time, building skin technologies are constantly improving. Electrochromic and thermochromic are two exciting new technologies that can help reduce the energy consumption of a building. The purpose of this work is to increase our understanding of how much the use of electrochromic (EC) and thermochromic (TC) technologies can reduce the energy consumption of residential and commercial buildings in two …

The Lampenflora In Show Caves And Its Treatment: An Emerging Ecological Problem, Carlos Baquedano Estévez, Luis Moreno Merino, Almudena De La Losa Román, Juan J. Durán Valsero

International Journal of Speleology

The artificial lighting of caves adapted for touristic visits, leads to the appearance and propagation of a complex community of phototrophic organisms known as “lampenflora”. Formed mainly by algae and cyanobacteria, they produce the degradation of the colonized substrates and decrease the show value of the caves. This phenomenon became famous worldwide in the 1960s due to the damage caused to the paintings in the Lascaux Cave (France). Since then it has become an issue of serious concern to both managers of show caves and to the international scientific community. Over time, the problem has been approached following two complementary …

Design And Implementation Of Degenerate Qpcr/Qrt-Pcr Primers To Detect Microbial Nitrogen Metabolism In Wastewater And Wastewater-Related Samples, Ryan F. Keeley

USF Tampa Graduate Theses and Dissertations

Nitrogen cycling processes can be tracked using quantitative Polymerase Chain Reaction (qPCR) to determine the presence and qReverse Transcriptase-PCR (qRT-PCR) to determine expression of key genes, or ‘biological markers’, for nitrogen metabolism. Nitrification is catalyzed in part, by two enzymes: ammonia monooxygenase (AMO; NH3 NH2OH) and nitrite oxidoreductase (NXR; NO2- NO3-). For denitrification, four enzymes act sequentially: nitrate reductase (NAR/NAP; NO3- NO2-), nitrite reductase (NIR; NO2- NO), nitric oxide reductase (NOR; NO  N2O), and nitrous oxide reductase (NOS; N2O  N2). A principle of wastewater treatment (WWT) is to remove excess nitrogen by taking advantage of natural nitrogen cycling …

Breakdown Mechanisms In Iron Caves. An Example From Brazil, Marcelo R. Barbosa, Allan D.F. Da Silva, Rafael G. De Paula, Georgete M. Dutra, Airton Barata, Iuri V. Brandi, Chrystophe R.P. Da Silva, Robert A. Osborne

International Journal of Speleology

An iron cave in the vicinity of a mine in Carajás, Brazil, was selected to be mined within an assisted elimination project, planned to control all mine advancement operations towards the cave along with a strict speleological physical monitoring. It allowed, in a pioneering way, the recording of events in the cave from the first signs of damage until to the total collapse of the cave. The project lasted four years and it was possible to identify and describe four breakdown mechanisms in iron caves: Fragment downfall, Block downfall, Controlling structure reactivation, and Open discontinuity movement. The mechanisms occurred independently …

Solar Thermal Geothermal Hybrid System With A Bottoming Supercritical Organic Rankine Cycle, Francesca Moloney

USF Tampa Graduate Theses and Dissertations

Climate change has spurred an interest in renewable energy. Many renewable energy technologies are intermittent, such as solar energy, or are dependent on transient conditions such as the ambient temperature in the case of geothermal energy. While solar thermal energy is able to achieve high temperatures and efficiencies, geothermal energy is limited by its lower temperatures which results in low conversion efficiency. There is an opportunity to create a hybrid system using both solar thermal and geothermal energy to improve their stand-alone performance.

In the literature, solar-geothermal hybrid systems are limited by the temperature of the solar field and the …

Design Of Variable Wall Thickness Geometry And Performance Mapping Of Scroll Expanders For Distributed Power Generation, Arun Kumar Narasimhan

USF Tampa Graduate Theses and Dissertations

Low-temperature heat sources such as industrial waste heat, solar, and geothermal are more suitable for small-scale power generation rather than utility scale. In order to maximize the electricity generated from low-temperature heat sources, an efficient expansion device for small-scale power output is necessary. This research work has focused on evaluating the use of a scroll expander and improving its geometrical design for the power output range of 1-25 kW_e.

The first part of the work focusses on modeling the performance of a scroll expander using two non-dimensionless parameters, namely, specific speed and specific diameter. Performance of a scroll …

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

USF Tampa Graduate Theses and Dissertations

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

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

USF Tampa Graduate Theses and Dissertations

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

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

USF Tampa Graduate Theses and Dissertations

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

Design And Testing Of A Reciprocating Wind Harvester, Ahmet Topcuoglu

USF Tampa Graduate Theses and Dissertations

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

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

Prioritizing Rehabilitation Of Sanitary Sewers In Pinellas County, Fl, Jesse T. Hillman

USF Tampa Graduate Theses and Dissertations

Following large rain events, extraneous freshwater contributions known as inflow and infiltration (I/I) bypass the storm sewer and enter the sanitary sewer system. In areas with a high water table, like Pinellas County and the surrounding Tampa Bay area, a majority of the wastewater infrastructure is submerged year round exacerbating the rate of groundwater infiltration. This excess flow overloads the existing wastewater infrastructure leading to sanitary sewer overflows (SSOs). These SSOs result in serious problems for municipalities and utilities across the country.

This study was performed in order to assist Pinellas County Utilities in rehabilitating their southern sewer system. To …

Variations Of Sedimentary Biogenic Silica In The Gulf Of Mexico During The Deepwater Horizon And Ixtoc-I Oil Spill., Jong Jin Lee

USF Tampa Graduate Theses and Dissertations

The goal of this research is to understand the impacts of the 2010 Deepwater Horizon oil spill and the 1970-1980 IXTOC-I oil spill and other anthropogenic activity (e.g. dam construction) on surface water primary productivity by measuring sedimentary biogenic silica. It is known that sedimentary biogenic silica is distinct from mineral – bound silica, therefore it has been used as a proxy record for surface water primary productivity (e.g. diatom blooms). The Deepwater Horizon oil spill resulted in a widespread Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) event. The IXTOC-I oil spill was one of the largest oil spills …

Water Scarcity In The Face Of Hurricanes: Improving The Resilience Of Potable Water Supplies In Selected Florida Counties, Fautemeh Sajadi Bami

USF Tampa Graduate Theses and Dissertations

Severe storms can threaten the reliability and accessibility of drinking water supplies. The state of Florida is frequently impacted by hurricanes and is often struck more than once a year. An example of this can be found in 2017 when hurricanes Harvey, Irma, and Maria caused much damage. Compromised utilities, well contamination, and shortages in bottled water and ice are just some of the problems that may threaten peoples’ drinking water.

Faced with these issues, preparation and response efforts must be effective in order to promote human health. Recent events like Hurricane Irma caused shortages in potable water which suggest …

Storm Surge And Evacuations In Pinellas County, Christianne Pearce

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to determine evacuation decisions of residents in Pinellas County, a vulnerable area in Florida, during Hurricane Irma in 2017, and whether those decisions will impact their future decisions to evacuate. This study also examines the resident’s perception of storm surge flooding during a hurricane. To understand evacuation decisions and storm surge perceptions a survey was conducted on residents in vulnerable areas of Pinellas County. The survey examined multiple aspects including the role of media, relationships, and sociodemographic status on decision making. Another aspect examined if their decision to evacuate for Hurricane Irma will impact …

The Ability Of The U.S. Military’S Wbgt-Based Flag System To Recommend Safe Heat Stress Exposures, David R. Almario

USF Tampa Graduate Theses and Dissertations

The U.S. military currently uses a flag system based on wet-bulb globe temperature (WBGT) and metabolic rate to recommend heat stress exposure limits. This paper addresses the ability of the flag system to recommend safe heat exposures in a non-military population.

Two progressive heat stress studies provided data on 528 observations of safe or unsafe exposures of 4 hours over a range of WBGT conditions and metabolic rates using 29 participants wearing woven cotton clothing. For the two studies, range of WBGT conditions was 25 to 42C, and the range of metabolic rates was 100 to 650 watts. These exposures …

An Assessment Of The Influence Of Local Conditions On The Economic And Environmental Sustainability Of Drain Water Heat Recovery Systems, Anusha Ravichandran

USF Tampa Graduate Theses and Dissertations

Increasing resource demand and decreasing supplies necessitate a paradigm shift in wastewater management from treatment to resource recovery. As the economic and environmental performance of wastewater-based resource recovery systems is location-specific (e.g., terrain slope influences hydro-energy recovery), a holistic view of their sustainability requires a comprehensive analysis on the effect of the local conditions on these systems. Although the internal factors affecting such systems (e.g., water quality and end use) are well studied, there is limited literature on the effect of external factors such as topography, climate and population density. This study evaluated the role of climate and population density …

A Reply To The Comment On “Assessing Preservation Priorities Of Caves And Karst Areas Using The Frequency Of Endemic Cave-Dwelling Species” By Nitzu Et Al. (2018), Int. J. Speleol., 47 (1): 43-52, Eugen I. Nitzu, Ioana N. Meleg, Andrei Giurginca

International Journal of Speleology

No abstract provided.

Comment On “Assessing Preservation Priorities Of Caves And Karst Areas Using The Frequency Of Endemic Cave-Dwelling Species” By Nitzu Et Al. (2018), Int. J. Speleol., 47 (1): 43-52, Oana T. Moldovan, Traian Brad

International Journal of Speleology

No abstract provided.

Absorber And Window Study – Cdsexte1-X/Cdte Thin Film Solar Cells, Chih-An Hsu

USF Tampa Graduate Theses and Dissertations

CdTe an II-VI semiconductor has been a leading thin film photovoltaic material due to its near ideal bandgap and high absorption coefficient [1]. The typical thin film CdTe solar cells have been of the superstrate configuration with CdS (Eg-2.42eV) as the n-type heterojunction partner. Due to the relatively narrow bandgap of CdS, a wider bandgap n-type window layer has recently emerged as a promising substitute: alloys of MgyZn1-yO have been successfully used as the emitter or window layer. The benefits in the usage of MgyZn1-yO (MZO) are its tunable bandgap and wide optical spectrum on optoelectronic devices. Due to an …