Physical Sciences and Mathematics Commons^™

Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore

USF Tampa Graduate Theses and Dissertations

The flux of CO2 between the ocean and the atmosphere is an important measure in determining local, global, and regional, as well as short term and long term carbon budgets. In this study, air-sea CO2 fluxes measured using a floating chamber were used to examine the spatial and temporal variability of CO2 fluxes in Florida Bay. Measurements of dissolved inorganic carbon and total alkalinity obtained concurrently with chamber measurements of CO2 flux allowed calculation of ΔpCO2 from flux measurements obtained at zero wind velocity. Floating chamber measurements of ΔpCO2 were subsequently coupled with wind speed data to provide a simple …

Investigating The Role Of The Internet In Women And Minority Stem Participation: A Case Study Of Two Florida Engineering Programs, Arland Nguema Ndong

USF Tampa Graduate Theses and Dissertations

Despite our awareness of the fascination modern humans have with the Internet, little is known about how and why colleges and universities create and maintain Websites. At the most general level, in this case study, I hypothesize that university Websites serve as communication and marketing tools in attracting students. At the most specific level, I postulate that civil engineering programs with Web pages depicting images of women and minorities would be more successful in recruiting and retaining women and students of color than civil engineering programs with Web pages displaying fewer or no images of women and minorities. The primary …

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 …

Taxonomy And Geochemistry Of The Globigerinoides Ruber-Elongatus Plexus, With Paleontological Implications, Elizabeth Ann Brown

USF Tampa Graduate Theses and Dissertations

The reliability of foraminifera as stratigraphic index fossils, and as isotopic proxies of marine environments, is based on the assumption that the fossil concepts represent uniform species, responding consistently to their ambient environments. Understanding sources of uncertainty is, therefore, critical. In this dissertation, I explore a potential bias in the application of planktonic foraminifera utilized extensively for Cenozoic paleo-reconstruction and, to a lesser extent, biostratigraphy: the Globigerinoides ruber-elongatus plexus (‘plexus’ meaning a complex network of interconnected members). Taxonomic revisions since 1826 have resulted in the merging of multiple Globigerinoides species names under one general designation (“Globigerinoides ruber”), the implications of …

Solid-State Synthesis Of Imide Ligands For The Self-Assembly Of Metal-Organic Materials, Jason Alexander Perman

USF Tampa Graduate Theses and Dissertations

In this research project, reduction or complete elimination of organic solvents is explored in the synthesis of cyclic imides using a technique that brings reagents into favorable position to react. Cocrystal Controlled Solid-State Synthesis (C³S^y3), takes advantage of supramolecular interactions such as hydrogen bonding and π-π stacking to form a cocrystal which can sequential be heated to complete the condensation reaction and produce a desirable product. Twenty-five successful condensation reactions result in high and clean yield.

C³S^y3 of cyclic imides with auxiliary hydrogen bonding moieties like carboxylic acid, carboxylate or pyridyl groups are …

Fundamental Transversals On The Complexes Of Polyhedra, Joy D'Andrea

USF Tampa Graduate Theses and Dissertations

We present a formal description of `Face Fundamental Transversals' on the faces of the Complexes of polyhedra (meaning threedimensional polytopes). A Complex of a polyhedron is the collection of the vertex points of the polyhedron, line segment edges and polygonal faces of the polyhedron. We will prove that for the faces of any 3-dimensional complex of a polyhedron under face adjacency relations, that a `Face Fundamental Transversal' exists, and it is a union of the connected orbits of faces that are intersected exactly once. While exploring the problem of finding a face fundamental transversal, we have found a partial result …

An Analysis Of Remote Biometric Authentication With Windows, Brandy Marie Eyers

USF Tampa Graduate Theses and Dissertations

One thing that everyone seems to be worried about when it comes to his or her computer is security. If your computer is not secure then private information could be stolen. Many people now use passwords to protect themselves though they are discovering that using multi-factor authentication is much more secure. It allows you to use multiple different proofs of who you are. Biometrics is one of the ways to prove identity. Using it, you could log into a system with just a fingerprint, which is something that is very difficult to steal. We present a suite of software tools …

Mining Associations Using Directed Hypergraphs, Ramanuja N. Simha

USF Tampa Graduate Theses and Dissertations

This thesis proposes a novel directed hypergraph based model for any database. We introduce the notion of association rules for multi-valued attributes, which is an adaptation of the definition of quantitative association rules known in the literature. The association rules for multi-valued attributes are integrated in building the directed hypergraph model. This model allows to capture attribute-level associations and their strength. Basing on this model, we provide association-based similarity notions between any two attributes and present a method for finding clusters of similar attributes. We then propose algorithms to identify a subset of attributes known as a leading indicator that …

Knowledge Guided Non-Uniform Rational B-Spline (Nurbs) For Supporting Design Intent In Computer Aided Design (Cad) Modeling, Khairan Rajab

USF Tampa Graduate Theses and Dissertations

For many years, incompatible computer-aided design (CAD) packages that are based on Non-uniform Rational B-Spline (NURBS) technology carried out the exchange of models and data through either neutral file formats (IGES or STEP) or proprietary formats that have been accepted as quasi industry standards. Although it is the only available solution at the current time, the exchange process most often produces unsatisfactory results. Models that are impeccable in the original modeling system usually end up with gaps or intersections between surfaces on another incompatible system. Issues such as loss of information, change of data accuracy, inconsistent tolerance, and misinterpretation of …

A Sedimentary Record Of Regional Land-Use And Climate Change In The Manatee River, Manatee County, Florida, Patrick Schwing

USF Tampa Graduate Theses and Dissertations

The Manatee River Watershed (Manatee County, FL) has experienced heavy anthropogenic development over the last 100 years and was relatively pristine previous to this development. The population growth within the watershed has surpassed the national trends and has doubled in the last 30 years. The heavy anthropogenic development has led to depletion in natural resources, nutrient loading, coastal erosion, and increased pollution. This study constructs records of sedimentological processes to compare the pre-development records to the past 100 years of anthropogenic development. The first portion of this study identifies specific changes in sedimentation attributed to anthropogenic activity in the Manatee …

Optimization Of Proximity Judgment, Brian Day

USF Tampa Graduate Theses and Dissertations

As humans, we have evolved to see in three dimensions. Our ancestors developed two eyes that only look forward, which allows the visual area that can perceive depth to be most of the field of view. A variety of sensors have been developed which can determine depth in the environment. They range from producing individual points of depth to the depth of everything in the environment. These sensors have become cheap and can now reliably produce accurate depth. Research is needed to determine how to present the proximity information to the people using the sensors. Touch, sound, and vision have …

The Search For The Missing Mantles Of Differentiated Asteroids: Evidence From Taxonomic A-Class Asteroids And Olivine-Dominated Achondrite Meteorites, Michael Peter Lucas

USF Tampa Graduate Theses and Dissertations

The apparent rarity of taxonomic A-class asteroids poses a significant paradox for understanding asteroid differentiation and the dynamical evolution of the early solar system. Based on results from asteroid taxonomic surveys, and on the abundances and mineralogy of different achondrite meteorites, it appears that olivine-dominated mantle remnants are missing from both the asteroid population and in meteorite collections. Several scenarios to explain this paradox have been proposed: (1) olivine mantle material has been stripped away by collisions and only remains as small fragments (< ~5 km), (2) A-class asteroids are abundant but have been altered in some way masking their presence, or (3) differentiated asteroids did not form thick olivine-rich mantles.

We have approached these questions through the collection of taxonomic and observational data on known A-class …

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 …

From Source To Sink: An Isotopic Perspective On The Biogeochemical Relationship Between The Everglades And Florida Bay, Ana Maria Hoare

USF Tampa Graduate Theses and Dissertations

Increasing human populations and activities in coastal areas have led to high nutrient loading and estuarine ecosystem decline. Natural hydrological patterns in South Florida have been drastically altered by changes in water management and land use practices. As a result Florida Bay has experienced a series of negative ecosystem effects including hypersalinity events, degradation of water quality, and harmful algal blooms and declines in upper trophic level populations. To remediate ecosystem decline in Florida's coastal ecosystems, the Comprehensive Everglades Restoration Plan proposes to restore a more natural hydrologic flow in the Everglades. It is expected hydrologic restoration efforts will change …

Robotic Hand Evaluation Based On Task Specific Kinematic Requirements, Carlos Rafael Neninger

USF Tampa Graduate Theses and Dissertations

With the rise autonomous and robotic systems in field applications, the need for dexterous, highly adaptable end effectors has become a major research topic. Control mechanisms of robotics hands with a high number independent actuators is recognized as a complex, high dimensional problem, with exponentially complex algorithms. However, recent studies have shown that human hand motion possesses very high joint correlation which translates into a set of predefined postures, or synergies. The hand produces a motion using a complementing contribution of multiple joints, called synergies. The similarities place variables onto a common dimensional space, effectively reducing the number of independent …

Evanescent Wave Coupling Using Different Subwavelength Gratings For A Mems Accelerometer, Al-Aakhir A. Rogers

USF Tampa Graduate Theses and Dissertations

A novel technique of coupling near-field evanescent waves by means of variable period subwavelength gratings (1.2 ìm and 1.0 ìm), using a 1.55 ìm infrared semiconductor laser is presented for the use of an optical MEMS accelerometer. The subwavelength gratings were fabricated on both glass and silicon substrates respectively.

Optical simulation of the subwavelength gratings was carried out to obtain the maximum coupling efficiency of the two subwavelength gratings; the grating thickness, grating width, and the grating separation were optimized. This was performed for both silicon and glass substrates.

The simulations were used to determine the total system noise, including …

Modeling Direct Runoff Hydrographs With The Surge Function, Denis Voytenko

USF Tampa Graduate Theses and Dissertations

A surge function is a mathematical function of the form f(x)=ax^pe^-bx. We simplify the surge function by holding p constant at 1 and investigate the simplified form as a potential model to represent the full peak of a stream discharge hydrograph. The previously studied Weibull and gamma distributions are included for comparison. We develop an analysis algorithm which produces the best-fit parameters for every peak for each model function, and we process the data with a MATLAB script that uses spectral analysis to filter year-long, 15-minute, stream-discharge data sets. The filtering is necessary to locate the …

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. …

Synthesis Of Small Molecule Inhibitors Of Janus Kinase 2, Phosphodiesterase Iv, Gabaa And Nmda Receptors: Investigation Of Mcmurry, Mannich And Chemoenzymatic Strategies, Meghanath Gali

USF Tampa Graduate Theses and Dissertations

Stilbenoids possess a wide range of biological properties such as, anticancer, antiplatelet aggregation, antiestrogenic, antibacterial, antifungal and antiatherogenic, etc. Owing to these therapeutic values, a great deal of attention attracted in the synthesis of derivatives of stilbenes. During the course of the study, G6 a novel stilbenoid was discovered, through high throughput screening, to be a potent inhibitor of mutated JAK2-V617F. The mutated JAK2 variant has been implicated in various myeloproliferative disorders (MPDs) including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) has been targeted by therapeutics. Chapter 2 describes the synthesis of analogs of the stilbenoid G6 …

Electronic Structure Characterization Of Nanocrystalline Surfaces And Interfaces With Photoemission Spectroscopy, Sebastian Gutmann

USF Tampa Graduate Theses and Dissertations

In this study, photoemission spectroscopy (PES) was used to investigate the electronic properties of nanocrystalline titanium dioxide (TiO₂), zinc oxide (ZnO), and cadmium selenide (CdSe). Electrospray deposition technique enabled the preparation of thin films in vacuum from a dispersion prepared outside the vacuum chamber. This method also allowed the step-wise formation of interfaces and the monitoring of the evolution of the electronic structure with intermittent PES characterization.

The work function of nanocrystalline TiO₂ and ZnO was measured with ultraviolet photoemission spectroscopy (UPS) and low-intensity x-ray photoemission spectroscopy (LIXPS). Measurements on environmentally contaminated surfaces revealed an instantaneous and …

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 …

Physical Models Of Amyloid Fibril Assembly, Shannon Elizabeth Hill

USF Tampa Graduate Theses and Dissertations

Formation of large fibers and plaques by amyloid proteins is recognized as the molecular hallmark of an increasing number of human disorders, including Parkinson's disease, Alzheimer's disease and even type II diabetes. The broader objective of my research is to unravel the basic mechanisms that initiate and regulate fibril formation by amyloidogenic proteins. This objective is significant because even basic aspects of how fibril formation proceeds from a soluble, monomeric protein to an insoluble amyloid fibril remain much debated. Furthermore, there is increasingly strong evidence suggesting that intermediates of the aggregation process, with properties distinct from those of mature fibrils, …

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 …

Grouper: A Packet Classification Algorithm Allowing Time-Space Tradeoffs, Joshua Adam Kuhn

USF Tampa Graduate Theses and Dissertations

This thesis presents an algorithm for classifying packets according to arbitrary (including noncontiguous) bitmask rules. As its principal novelty, the algorithm is parameterized by the amount of memory available and can customize its data structures to optimize classification time without exceeding the given memory bound. The algorithm thus automatically trades time for space efficiency as needed. The two extremes of this time-space tradeoff (linear search through the rules versus a single table that maps every possible packet to its class number) are special cases of the general algorithm we present. Additional features of the algorithm include its simplicity, its open-source …

High-Resolution Event Stratigraphy Of Mm-Scale Laminated Sediments From Coastal Salt Ponds: St. John, Us Virgin Islands, Rebekka Amie Larson

USF Tampa Graduate Theses and Dissertations

A multi-proxy approach is utilized on mm- to cm-scale laminated sediment records in coastal salt ponds on St. John, U.S. Virgin Islands to characterize the sediments, identify their sources and depositional processes/events (heavy rainfall, tropical cyclones, tsunamis). Historical records are combined with high-resolution geochronology (short-lived radioisotopes, ²¹⁰Pb, ¹³⁷Cs, ⁷Be) and scanning elemental techniques (XRF and LA-ICP-MS) to link depositional events to how they are manifested in the sedimentary record. Volcanic rocks are the terrigenous sediment source and the sedimentary signature of terrigenous sediment in the geologic record consists of higher amounts of Al, Fe, Ti, Co, and …

Assessment Of The Dependence Of Ventilation Image Calculation From 4d-Ct On Deformation And Ventilation Algorithms, Kujtim Latifi

USF Tampa Graduate Theses and Dissertations

Ventilation imaging using 4D-CT is a convenient and cost effective functional imaging methodology which might be of value in radiotherapy treatment planning to spare functional lung volumes. To calculate ventilation imaging from 4D-CT we must use deformable image registration (DIR). This study validates the DIR methods and investigates the dependence of calculated ventilation on DIR methods and ventilation algorithms.

The first hypothesis is if ventilation algorithms are robust then they will be insensitive to the precise DIR used provided the DIR is accurate. The second hypothesis is that the change in Houndsfield Unit (HU) method is less dependent on the …

Automorphism Groups Of Quandles, Jennifer Macquarrie

USF Tampa Graduate Theses and Dissertations

This thesis arose from a desire to better understand the structures of automorphism groups and inner automorphism groups of quandles. We compute and give the structure of the automorphism groups of all dihedral quandles. In their paper Matrices and Finite Quandles, Ho and Nelson found all quandles (up to isomorphism) of orders 3, 4, and 5 and determined their automorphism groups. Here we find the automorphism groups of all quandles of orders 6 and 7. There are, up to isomoprhism, 73 quandles of order 6 and 289 quandles of order 7.

Crystal Engineering Of Pharmaceutical Cocrystals, Sreya Mukherjee

USF Tampa Graduate Theses and Dissertations

Pharmaceutical cocrystals use principles of crystal engineering for the design of crystalline forms of drugs and can improve their solubility, bioavailability, stability and other important properties without changing the efficacy of the drug. Herein reported are pharmaceutical cocrystals of two API's, caffeine and Pentoxifylline.

Research has indicated that caffeine has the ability to reverse AB; plaque deposition in the brain (believed to be the primary cause of Alzheimer's pathogenesis) and thus revert memory and improve cognitive impairment. But owing to the fast absorption rate and short half life, a controlled release formulation of caffeine would be clinically beneficial. Thus, novel …

Selection And Implementation Of Technologies For The Re-Engineering Of An Existing Software System, Stan William Naspinski

USF Tampa Graduate Theses and Dissertations

A major hurdle for any company to cross is the act of re-engineering software if they wish to stay relevant. With the speed that software and technology advances, it would be ignorant for any product to stagnate. With that comes the inherent difficulties of choosing which of the older technologies to keep (if any) and which newer technologies to employ in the re-engineered solution. Once that is covered, the actual implementation presents its own set of challenges to both the decision makers and developers in the process.

This thesis describes a case study, in particular the efforts put forth to …

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 …