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Full-Text Articles in Physical Sciences and Mathematics

Quasi 3-Dimensional Electrical Resistivity Mapping Of Air-Filled Karst Conduits And Policy Implications, Charles W. Mccrackin Oct 2011

Quasi 3-Dimensional Electrical Resistivity Mapping Of Air-Filled Karst Conduits And Policy Implications, Charles W. Mccrackin

USF Tampa Graduate Theses and Dissertations

This study assesses the capability and practical applications of quasi 3-Dimensional (3D) electrical resistivity surveying (ER) for mapping air-filled karst conduits. Vadose zone caves within the Brooksville Ridge of West Central Florida are relatively similar in architecture, with N-S elongation, and do not consist of an interconnected network of conduits. A high resolution quasi-3D ER survey was performed over two mapped cave systems on the Brooksville Ridge. The resultant survey verified the general effectiveness of quasi-3D ER in locating the two known near-surface cave features. Several other locations in the survey show similar or stronger resistivity anomalies trending in a …


Tracking The Deepwater Horizon Oil Spill: A Modeling Perspective, Yonggang Liu, Robert H. Weisberg, Chuanmin Hu, Lianyuan Zheng Feb 2011

Tracking The Deepwater Horizon Oil Spill: A Modeling Perspective, Yonggang Liu, Robert H. Weisberg, Chuanmin Hu, Lianyuan Zheng

Yonggang Liu

The Deepwater Horizon oil spill was caused by a drilling rig explosion on 20 April 2010 that killed 11 people. It was the largest oil spill in U.S. history and presented an unprecedented threat to Gulf of Mexico marine resources. Although oil gushing to the surface diminished after the well was capped, on 15 July 2010, much remains to be known about the oil and the dispersants beneath the surface, including their trajectories and effects on marine life. A system for tracking the oil, both at the surface and at depth, was needed for mitigation efforts and ship survey guidance. …


Statistical Analysis And Mechanistic Modeling Of Water Quality: Hillsborough Bay, Florida, Keith Hackett Jan 2011

Statistical Analysis And Mechanistic Modeling Of Water Quality: Hillsborough Bay, Florida, Keith Hackett

USF Tampa Graduate Theses and Dissertations

Nutrient pollution has been identified as a significant threat to U.S. coastal and estuarine water quality. Though coastal and estuarine waters need nutrients to maintain a healthy, productive ecosystem, excess nutrients can lead to eutrophication. There are significant potential negative consequences associated with eutrophication, including loss of habitat, loss of economic activity, and direct threats to human health. Hillsborough Bay experienced eutrophication in the 1960s and 1970s due to a rapidly growing population and associated increases in nutrient pollution. These eutrophic conditions led to more frequent phytoplankton and macroalgae blooms and declines in seagrasses. To address these problems, a series …


Evaluation Of Trajectory Modeling In Different Dynamic Regions Using Normalized Cumulative Lagrangian Separation, Yonggang Liu, Robert H. Weisberg Jan 2011

Evaluation Of Trajectory Modeling In Different Dynamic Regions Using Normalized Cumulative Lagrangian Separation, Yonggang Liu, Robert H. Weisberg

Yonggang Liu

The Lagrangian separation distance between the endpoints of simulated and observed drifter trajectories is often used to assess the performance of numerical particle trajectory models. However, the separation distance fails to indicate relative model performance in weak and strong current regions, such as a continental shelf and its adjacent deep ocean. A new skill score is proposed based on the cumulative Lagrangian separation distances normalized by the associated cumulative trajectory lengths. This skill score is used to evaluate surface trajectories implied by Global HYCOM hindcast surface currents as gauged against actual satellite-tracked drifter trajectories in the eastern Gulf of Mexico …


Evolution Of The Loop Current System During The Deepwater Horizon Oil Spill Event As Observed With Drifters And Satellites, Yonggang Liu, Robert H. Weisberg, Charles Kovach, Rolf Riethmüller Jan 2011

Evolution Of The Loop Current System During The Deepwater Horizon Oil Spill Event As Observed With Drifters And Satellites, Yonggang Liu, Robert H. Weisberg, Charles Kovach, Rolf Riethmüller

Yonggang Liu

The ocean circulation patterns of the Gulf of Mexico (GOM) Loop Current (LC) system and their effects on the advection of the oil discharged during the Deepwater Horizon incident are described using in situ surface drifter trajectories and satellite observations from May to August 2010. These observations include altimetry-derived surface geostrophic velocities, sea surface temperature, ocean color, and surface oil locations. The elongated, northwestward penetrating LC retreated back from its northernmost position in late April 2010 and stayed farther away from the surface oil in the north during May 2010. Although the main body of the surface oil slick remained …


A Comparison Of Ecological Conditions And Relationships In An Altered Wetland And An Unaltered Wetland, Mark Kiyoshi Hurst Jan 2011

A Comparison Of Ecological Conditions And Relationships In An Altered Wetland And An Unaltered Wetland, Mark Kiyoshi Hurst

USF Tampa Graduate Theses and Dissertations

The purpose of the study is to identify and quantify the hydrologic and ecologic differences between two adjacent sections of Colt Creek; one section unaltered and one section altered by clearing and drainage. These differences were measured by monitoring water levels, groundcover vegetation in each of the two areas, and monitoring numbers and species of birds utilizing the two areas. Surface water levels were measured in three locations: in the historic Colt Creek flow way, in the ditch draining the creek, and in an adjacent wetland strand. In addition, a shallow monitor well in the creek was used to measure …


The Impact Of Supply Chain And Network Structure On The Environmental Performance Of Sustainability-Focused Companies, Ozan Ozcan Jan 2011

The Impact Of Supply Chain And Network Structure On The Environmental Performance Of Sustainability-Focused Companies, Ozan Ozcan

USF Tampa Graduate Theses and Dissertations

The goal of this dissertation was to contribute to our understanding of the relationship between supply chain structure and the pursuit of a sustainability-driven corporate strategy. The literature indicates that in order to pursue a sustainability-focused strategy, an increased level of integration across the supply chain is required. However, there are also industry-level dynamics that impact observed levels of vertical integration. That is, some industries are naturally more integrated than others based on the maturity level of the industry. Thus, some firms may experience opposing forces regarding their sourcing strategies once they choose to pursue a sustainability-focused strategy.

To explore …


Analytical Methods To Support Risk Identification And Analysis In Healthcare Systems, Laila Nadime Cure Vellojin Jan 2011

Analytical Methods To Support Risk Identification And Analysis In Healthcare Systems, Laila Nadime Cure Vellojin

USF Tampa Graduate Theses and Dissertations

Healthcare systems require continuous monitoring of risk to prevent adverse events. Risk analysis is a time consuming activity that depends on the background of analysts and available data. Patient safety data is often incomplete and biased. This research proposes systematic approaches to monitor risk in healthcare using available patient safety data. The methodologies combine traditional healthcare risk analysis methods with safety theory concepts, in an innovative manner, to allocate available evidence to potential risk sources throughout the system. We propose the use of data mining to analyze near-miss reports and guide the identification of risk sources. In addition, we propose …


Smart Grid Functionality Of A Pv-Energy Storage System, Nenad Damnjanovic Jan 2011

Smart Grid Functionality Of A Pv-Energy Storage System, Nenad Damnjanovic

USF Tampa Graduate Theses and Dissertations

Renewable Energy will be the key to preserving the Earth's remaining resources and continuing this surge of technological progress that we have experienced this past century. New philosophies of how/when/where energy should be consumed and produced are attempting to improve upon the current grid infrastructure. The massive advancement in communications, renewable and control systems will allow this new-age electric grid to maximize its efficiency while reducing cost. Renewable, "green" energy is now at the forefront of innovation. As the world population increases, there will be a need to free ourselves from natural resources as much as possible. Advanced Energy Storage …


Apparent Total Evaporative Resistance Values From Human Trials Over A Range Of Metabolic And Heat Stress Levels, Matthew David Dooris Jan 2011

Apparent Total Evaporative Resistance Values From Human Trials Over A Range Of Metabolic And Heat Stress Levels, Matthew David Dooris

USF Tampa Graduate Theses and Dissertations

Failure to maintain thermal equilibrium can cause uncontrollable increases in body core temperature beyond critical upper limits. In selecting clothing, consideration must be given to the heat transfer properties of clothing that may restrict the cooling capacity of the human body under heat stress conditions, most importantly, apparent total evaporative resistance (Re,T,a). This study calculated and compared Re,T,a for five clothing ensembles under varying heat stress conditions, including three relative humidity (RH) levels and three stages of heat stress to determine if Re,T,a values varied or remained the same with …


A Pilot Study Of Small-Scale Variations In Outdoor Benzene Concentrations, Samantha Catherine Fridh Jan 2011

A Pilot Study Of Small-Scale Variations In Outdoor Benzene Concentrations, Samantha Catherine Fridh

USF Tampa Graduate Theses and Dissertations

Benzene is an important toxic chemical in urban air and known human carcinogen released substantially by mobile sources. It's important to understand the spatial variation of benzene concentrations in order to understand exposures of susceptible sub-populations such as children and minority groups. Current monitoring networks use large and expensive air samplers that require electricity and restrict the location and number of samplers, not allowing for fine spatial resolution data.

The goals of this study are to develop and evaluate protocols for passive sampling and analysis of ambient benzene concentrations, and conduct a pilot study investigating small-scale variations over an area …


Population Biology, Ecology, And Ecosystem Contributions Of The Eastern Oyster (Crassostrea Virginica) From Natural And Artificial Habitats In Tampa Bay, Florida, Michael Drexler Jan 2011

Population Biology, Ecology, And Ecosystem Contributions Of The Eastern Oyster (Crassostrea Virginica) From Natural And Artificial Habitats In Tampa Bay, Florida, Michael Drexler

USF Tampa Graduate Theses and Dissertations

The objective of this project was to document the status of oysters, Crassostrea virginica, from non-reef habitats throughout Tampa Bay, Florida, and assess the ecosystem contributions of those populations relative to reef-dwelling oysters. The aspects of oyster ecology studied here include condition, prevalence and intensity of disease (Perkinsus marinus - dermo), reproductive activity (including stage, fecundity, and juvenile recruitment), adult oyster density, and the faunal community associated with the oysters.

The predominant source of variation was seasonal, with lesser contributions among sites, and in most cases, little or no effect of the habitat type. Oysters populations from each habitat …


Simplified Methodology For Designing Parabolic Trough Solar Power Plants, Ricardo Vasquez Padilla Jan 2011

Simplified Methodology For Designing Parabolic Trough Solar Power Plants, Ricardo Vasquez Padilla

USF Tampa Graduate Theses and Dissertations

The performance of parabolic trough based solar power plants over the last 25 years has proven that this technology is an excellent alternative for the commercial power industry. Compared to conventional power plants, parabolic trough solar power plants produce significantly lower levels of carbon dioxide, although additional research is required to bring the cost of concentrator solar plants to a competitive level. The cost reduction is focused on three areas: thermodynamic efficiency improvements by research and development, scaling up of the unit size, and mass production of the equipment. The optimum design, performance simulation and cost analysis of the parabolic …


Statistical Models For Environmental And Health Sciences, Yong Xu Jan 2011

Statistical Models For Environmental And Health Sciences, Yong Xu

USF Tampa Graduate Theses and Dissertations

Statistical analysis and modeling are useful for understanding the behavior of different phenomena. In this study we will focus on two areas of applications: Global warming and cancer research. Global Warming is one of the major environmental challenge people face nowadays and cancer is one of the major health problem that people need to solve.

For Global Warming, we are interest to do research on two major contributable variables: Carbon dioxide (CO2) and atmosphere temperature. We will model carbon dioxide in the atmosphere data with a system of differential equations. We will develop a differential equation for each of six …


Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North Jan 2011

Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North

Environmental Sustainability Books

Jointly sponsored by the Hoffman Environmental Research Institute, the National Cave & Karst Research Institute, and the International Association of Hydrogeologists, the 2011 International Conference on Karst Hydrogeology and Ecosystems was held at Western Kentucky University in Bowling Green, Kentucy on 8-10 June 2011. Topics include karst geomorphology, engineering and modeling, isotope geochemistry, and cultural and educational aspects of karst environments.


Environmental Health In The Latin American And Caribbean Region: Use Of Water Storage Containers, Water Quality, And Community Perception, Erlande Omisca Jan 2011

Environmental Health In The Latin American And Caribbean Region: Use Of Water Storage Containers, Water Quality, And Community Perception, Erlande Omisca

USF Tampa Graduate Theses and Dissertations

Water quality and availability are important issues in many developing countries where portions of populations still lack access to potable water. Throughout the English-speaking Caribbean and parts of Latin America, households and businesses invest in water supply systems even when they are connected to and pay for water services from a private or state owned provider. Inconsistent supplies of water from the water companies have led many people to invest in storage tanks which, if operated correctly, can provide water throughout the day even when the supply from the main is low or zero. While these individual systems help to …


A Modeling Analysis Of Dissolved Carbon Dioxide Discharged From Howard F. Curren Advanced Wastewater Treatment Plant, Dustin Capps Jan 2011

A Modeling Analysis Of Dissolved Carbon Dioxide Discharged From Howard F. Curren Advanced Wastewater Treatment Plant, Dustin Capps

USF Tampa Graduate Theses and Dissertations

Currently, the US Environmental Protection Agency primarily regulates the discharge of dissolved nitrogen and phosphorous from wastewater treatment plants in the United States. A recent study has shown that the treated effluent of many plants contains concentrations of dissolved carbon dioxide well above the expected theoretical equilibrium concentration of 0.6 mg/L, indicating that carbon dioxide may have been overlooked as a possible pollutant in receiving waters. For this reason, it is necessary to examine the possible presence of a discharge plume containing high levels of dissolved CO2 downstream from the outfall of a major wastewater treatment plant in Tampa, Florida. …


An Examination Of The Impacts Of Urbanization On Green Space Access And Water Resources: A Developed And Developing World Perspective, Heather E. Wright Wendel Jan 2011

An Examination Of The Impacts Of Urbanization On Green Space Access And Water Resources: A Developed And Developing World Perspective, Heather E. Wright Wendel

USF Tampa Graduate Theses and Dissertations

This dissertation addresses the impact of urbanization and land use change on the availability and accessibility of two urban amenities that are often inequitably distributed: green space and water features. Diverse methodologies were utilized in order to gain a better understanding of the role of these amenities in improving urban quality of life and integrated water management. Using an interdisciplinary approach, this research provides a unique perspective within both a developed and developing world context by evaluating aspects of urbanization to emphasize more sustainable and integrated approaches to development.

A preliminary analysis highlights potential drivers of green space revitalization in …


Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do Jan 2011

Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do

USF Tampa Graduate Theses and Dissertations

To date, most studies on the fate and removal of endocrine disrupting compounds (EDCs) and pharmaceutical and personal care products (PPCPs) in wastewater focus on their fate in municipal wastewater treatment plants, and mostly under aerobic condition. There are limited studies related to anaerobic condition and (to our knowledge) no study on the removal of EDCs in landfill leachate by AnMBR. Moreover, for most studies under anaerobic condition, the removal of EDCs was only reported in the liquid phase; solid phase extraction was not reported, thereby preventing mass balance in the studies.

This research was conducted to investigate the potential …


Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi Jan 2011

Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi

USF Tampa Graduate Theses and Dissertations

In the rural areas of Madagascar only 29% of the population has access to clean water and 10% has access to improved sanitation. It has been estimated that environmental risk factors, such as inadequate access to clean drinking water and proper sanitation, are responsible for 94% of the diarrheal disease burden. This study was focused on testing a point-of-use technology called the Tulip filter, which is a siphon ceramic candle filter impregnated with silver. The purpose is to assess its feasibility for implementation in rural regions of Madagascar through a laboratory study performed at the University of South Florida.

The …


Examining Reasons For Bottled Water Consumption: A Case Study In Pensacola, Florida, Marina Leigh Foote Jan 2011

Examining Reasons For Bottled Water Consumption: A Case Study In Pensacola, Florida, Marina Leigh Foote

USF Tampa Graduate Theses and Dissertations

Over-consumption in developed economies undoubtedly puts a large strain on the environment, and many would argue that the damage is irreversible. Current uses and rates of consumption of freshwater resources are also deemed to be unsustainable. A large contributor to the high demand for water is the shift in consumer preferences from tap to bottled water. In the last few decades, bottled water companies have set unprecedented records, surpassing all other types of non-alcoholic beverages to become the second largest beverage market next to soda. Bottled water has been on the rise due to its supposed safety, purity and convenience. …


Relative Abundance And Spatial Distribution Of Lepomid Sunfishes In The Peace River, Justin Henry Heller Jan 2011

Relative Abundance And Spatial Distribution Of Lepomid Sunfishes In The Peace River, Justin Henry Heller

USF Tampa Graduate Theses and Dissertations

This study examines spatially continuous sampling data in order to investigate patterns of abundance and distribution of three recreationally important sunfish species (bluegill, redear, and spotted sunfish) along the main-stem of the Peace River, a large softwater river located in southwest Florida. A total of 467 electrofishing transects were sampled biannually from spring 2008 to spring 2010. Sampling sites ranged from the headwaters of the Peace River in Polk County, FL to the oligohaline waters located in Charlotte County, FL. All fish were collected with boat mounted electrofishing gear, and aquatic habitat and physiochemical water quality measurements were recorded at …


Road-Based Landscape Metrics For Quantifying Habitat Fragmentation, Rebecca Whitehead Loraamm Jan 2011

Road-Based Landscape Metrics For Quantifying Habitat Fragmentation, Rebecca Whitehead Loraamm

USF Tampa Graduate Theses and Dissertations

Landscape metrics measure the composition and configuration of habitats within landscapes; often the goal is to measure fragmentation. While a variety of existing metrics characterize the connectivity and contiguity of habitat patches, most do not explicitly consider the fragmenting effects of roads in their formulations. This research develops a set of new landscape metrics that explicitly quantify how roads disconnect and break apart habitat patches. This research introduces the following four metrics to consider the fragmenting effects of transportation networks: (1) Number of Connected Patches, a measure of connectivity; (2) Euclidean Nearest Neighbor-Roads, a measure of proximity; (3) Road Density, …


Assessment Of A Countywide Stormwater Pond Improvement Project: Impacts Of The Hillsborough County Adopt-A-Pond Program, Anthony Thomas Betts Jan 2011

Assessment Of A Countywide Stormwater Pond Improvement Project: Impacts Of The Hillsborough County Adopt-A-Pond Program, Anthony Thomas Betts

USF Tampa Graduate Theses and Dissertations

Comparative research was conducted to assess the environmental impacts of the Adopt-a-Pond program, which operates throughout Hillsborough County, Florida. The Adopt-a-Pond program was established in 1992 and designed to address nonpoint pollution through outreach and stormwater pond enhancement. However, the program had never been thoroughly and scientifically evaluated. Therefore, assessments of water quality and vegetative characteristics were made at ninety Adopt-a-Pond participants and eleven control ponds to explore the potential impacts of the program on measurable environmental parameters. Statistical analysis of the results failed to demonstrate any statistically significant environmental improvements associated with the Adopt-a-Pond program, and measures of program …


The Influence Of Meteorological Parameters On Rainfall And Severe Weather In Pinellas County, Fl, Cristina A. Mazza Jan 2011

The Influence Of Meteorological Parameters On Rainfall And Severe Weather In Pinellas County, Fl, Cristina A. Mazza

USF Tampa Graduate Theses and Dissertations

Pinellas County is located on a peninsula in Florida that experiences daily patterns of sea breeze associated rainfall mainly during the summer months of June through August. Previously, rainfall patterns, amounts and timing and severe weather in Pinellas County have not been examined considering dominant wind flow patterns, sea breeze circulations and other atmospheric variables. To improve forecasting of local mesoscale phenomena, this project examined the rainfall patterns, amounts and timing and severe weather occurrences that occur as a result of sea breezes and associated prevailing wind regimes within Pinellas County for the months of June, July and August for …


Evaluating The Effects Of Beach Nourishment On Loggerhead Sea Turtle (Caretta Caretta) Nesting In Pinellas County, Florida, Corey R. Leonard Ozan Jan 2011

Evaluating The Effects Of Beach Nourishment On Loggerhead Sea Turtle (Caretta Caretta) Nesting In Pinellas County, Florida, Corey R. Leonard Ozan

USF Tampa Graduate Theses and Dissertations

The health of Florida's beaches are vital to the survival of loggerhead sea turtles (Caretta caretta), as nearly half of the world's loggerheads nest on the states beaches. Many of the beaches utilized by the turtles have undergone nourishment projects in hopes of combating erosion of the shoreline, protecting beachfront property, and creating more suitable beaches for tourism. Although it is argued that beach nourishment benefits sea turtles by providing more nesting habitat, the effects of the Pinellas County nourishment projects on loggerhead nesting are unknown. Beach nourishment can alter the compaction, moisture content, and temperature of the sand, all …


Evaluating The Effectiveness Of Irrigation Restrictions Within Key Communities In Tampa, Florida, Lin Allen Ozan Jan 2011

Evaluating The Effectiveness Of Irrigation Restrictions Within Key Communities In Tampa, Florida, Lin Allen Ozan

USF Tampa Graduate Theses and Dissertations

The City of Tampa, Florida has instituted water restrictions over the past decade that have been primarily aimed at mitigating non-essential usage of water resources by limiting domestic lawn irrigation. The mandatory restrictions are enforced by the issuance of citations to violators, which is intended to promote compliance and deter from subsequent violations. This thesis provides a thorough investigation of historical water restriction with relation to compliance in order to determine which factors might be related to high rates of water usage within key Tampa communities. The objectives are to: (1) develop a GIS data set that can be used …


Stable Isotope Studies Of Paleoenvironment And Paleoclimate From Afar, Ethiopia, Zelalem K. Bedaso Jan 2011

Stable Isotope Studies Of Paleoenvironment And Paleoclimate From Afar, Ethiopia, Zelalem K. Bedaso

USF Tampa Graduate Theses and Dissertations

The sedimentary deposits of the Hadar Formation at Dikika and the Mount Galili Formation at Galili preserve a wealth of paleoenvironmental and paleoclimatic records spanning the last 5.29 Ma. Stable carbon and oxygen isotopic compositions of herbivore tooth enamel were analyzed for more than 600 specimens of 15 different taxa from 10 stratigraphic intervals. The application of carbon and oxygen isotopes here aims principally at reconstructing shifts in the relative abundance of C4 grasses, and its implications for climate indicators including temperature, aridity, and seasonality. The full range of δ13Cenamel values throughout the Plio-Pleistocene signifies a …


Informal Karst Education In The United States And Internationally, Leslie A. North Jan 2011

Informal Karst Education In The United States And Internationally, Leslie A. North

USF Tampa Graduate Theses and Dissertations

Despite the abundance of karst terrains and the important role they play in a wide variety of roles including supplying freshwater drinking supplies, no single, comprehensive study investigates the role of informal education for the improved understanding and protection of the terrains. Commonly overlooked anthropogenic karst disturbances partially occur because of the poor dissemination of scientific information to the general populace and policymakers and budgetary and time constraints of municipalities, thus generating a need to use informal education to fill these shortcomings. The purpose of this study was to: 1) establish the status of and quantify the amount of karst-related …