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Field Quantization For Radiative Decay Of Plasmons In Finite And Infinite Geometries, Maryam Bagherian Mar 2019

Field Quantization For Radiative Decay Of Plasmons In Finite And Infinite Geometries, Maryam Bagherian

USF Tampa Graduate Theses and Dissertations

We investigate field quantization in high-curvature geometries. The models and calculations can help with understanding the elastic and inelastic scattering of photons and electrons in nanostructures and probe-like metallic domains. The results find important applications in high-resolution photonic and electronic modalities of scanning probe microscopy, nano-optics, plasmonics, and quantum sensing.

Quasistatic formulation, leading to nonretarded quantities, is employed and justified on the basis of the nanoscale, here subwavelength, dimensions of the considered domains of interest.

Within the quasistatic framework, we represent the nanostructure material domains with frequency-dependent dielectric functions. Quantities associated with the normal modes of the electronic systems, the …


Regeneration Of Trace Metals During Phytoplankton Decay: An Experimental Study, Adrienne P. Hollister Mar 2019

Regeneration Of Trace Metals During Phytoplankton Decay: An Experimental Study, Adrienne P. Hollister

USF Tampa Graduate Theses and Dissertations

Trace metals act as important nutrients, and sometimes toxins, to phytoplankton and other marine microorganisms. When phytoplankton decay, the elements in their cells are released back into the water column through regeneration (also referred to as remineralization), one of the processes responsible for governing concentrations of dissolved trace metals and macronutrients in depth profiles. In order to experimentally study regeneration, controlled experimental incubations of mixed phytoplankton assemblages from the Gulf of Mexico (GoM) and monocultures of the diatom Pseudo-nitzschia dolorosa and the dinoflagellate Karenia brevis were placed in the dark and monitored as they decayed with naturally present bacteria. Over …


An Assessment Of The Influence Of Local Conditions On The Economic And Environmental Sustainability Of Drain Water Heat Recovery Systems, Anusha Ravichandran Mar 2019

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 …


Cave Dripwater Isotopic Signals Related To The Altitudinal Gradient Of Mount-Lebanon: Implication For Speleothem Studies, Carole Nehme, Sophie Verheyden, Fadi H. Nader, Jocelyne Adjizian-Gerard, Dominique Genty, Kevin De Bont, Benedicte Minster, Ghada Salem, David Verstraten, Philippe Clayes Mar 2019

Cave Dripwater Isotopic Signals Related To The Altitudinal Gradient Of Mount-Lebanon: Implication For Speleothem Studies, Carole Nehme, Sophie Verheyden, Fadi H. Nader, Jocelyne Adjizian-Gerard, Dominique Genty, Kevin De Bont, Benedicte Minster, Ghada Salem, David Verstraten, Philippe Clayes

International Journal of Speleology

An important step in paleoclimate reconstructions based on vadose cave carbonate deposits or speleothems is to evaluate the sensitivity of the cave environment and speleothems to regional climate. Accordingly, we studied four caves, located at different altitudes along the western flank of Mount-Lebanon (Eastern Mediterranean). The objectives of this study are to identify the present-day variability in temperature, pCO2, and water isotopic composition and to assess the possible influence of the altitudinal gradient on cave drip waters and cave streams. We present here an overview of the spatial variability of rainwater based on local and regional data, and …


Ice-Cliff Failure Via Retrogressive Slumping, Byron R. Parizek, Knut Christianson, Richard B. Alley, Denis Voytenko, Irena Vaňková, Timothy H. Dixon, Ryan T. Walker, David M. Holland Mar 2019

Ice-Cliff Failure Via Retrogressive Slumping, Byron R. Parizek, Knut Christianson, Richard B. Alley, Denis Voytenko, Irena Vaňková, Timothy H. Dixon, Ryan T. Walker, David M. Holland

School of Geosciences Faculty and Staff Publications

Retrogressive slumping could accelerate sea-level rise if ice-sheet retreat generates ice cliffs much taller than observed today. The tallest ice cliffs, which extend roughly 100 m above sea level, calve only after ice-flow processes thin the ice to near flotation. Above some ice-cliff height limit, the stress state in ice will satisfy the material-failure criterion, resulting in faster brittle failure. New terrestrial radar data from Helheim Glacier, Greenland, suggest that taller subaerial cliffs are prone to failure by slumping, unloading submarine ice to allow buoyancy-driven full-thickness calving. Full-Stokes diagnostic modeling shows that the threshold cliff height for slumping is likely …


Mechanical Significance Of Morphological Variation In Diprotodont Incisors, Philip J.R. Morris, Philip G. Cox, Samuel N. Cobb Mar 2019

Mechanical Significance Of Morphological Variation In Diprotodont Incisors, Philip J.R. Morris, Philip G. Cox, Samuel N. Cobb

School of Geosciences Faculty and Staff Publications

All rodents possess a single pair of enlarged incisors that grow throughout life. This condition (diprotodonty) is characteristic of Rodentia, but is also found in other mammals such as lagomorphs, hyraxes, the aye-aye and common wombat. This study surveyed lower incisor morphology across extant diprotodonts to examine shape variation within and between rodents and other diprotodonts, and to determine if tooth shape varies in a manner predictable from mechanics. Six linear and area variables were recorded from microCT scans of the mandibles of 33 diprotodont mammals. The curvature of the rodent lower incisors, as measured by the proportion of a …


Timing And Rates Of Events In The Generic Volcanic Earthquake Swarm Model, Tianyu Rong Feb 2019

Timing And Rates Of Events In The Generic Volcanic Earthquake Swarm Model, Tianyu Rong

USF Tampa Graduate Theses and Dissertations

In this thesis I combine data from 29 volcanic earthquake swarms that follow the pattern predicted by the Generic Volcanic Earthquake Swarm Model (GVESM; Benoit and McNutt, 1996) to investigate whether the relative timing of various parameters of pre-eruptive volcanic earthquake swarms could be used to forecast the time of an impending eruption. Based on the analysis of seismic unrest preceding many eruptions, the GVESM suggests that it is common to see an increase first in high-frequency earthquakes, then low-frequency earthquakes, then the onset of volcanic tremor. While this pattern is useful to volcano-seismologists, the relative timing and durations of …


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 Feb 2019

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 Feb 2019

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.


Detecting Rtl Trojans Using Artificial Immune Systems And High Level Behavior Classification, Farhath Zareen Feb 2019

Detecting Rtl Trojans Using Artificial Immune Systems And High Level Behavior Classification, Farhath Zareen

USF Tampa Graduate Theses and Dissertations

Security assurance in a computer system can be viewed as distinguishing between self and non-self. Artificial Immune Systems (AIS) are a class of machine learning (ML) techniques inspired by the behavior of innate biological immune systems, which have evolved to accurately classify self-behavior from non-self-behavior. This work aims to leverage AIS-based ML techniques for identifying certain behavioral traits in high level hardware descriptions, including unsafe or undesirable behaviors, whether such behavior exists due to human error during development or due to intentional, malicious circuit modifications, known as hardware Trojans, without the need fora golden reference model. We explore the use …


Exploring The Behavior Of Model Fit Criteria In The Bayesian Approximate Measurement Invariance: A Simulation Study, Abeer Atallah S. Alamri Feb 2019

Exploring The Behavior Of Model Fit Criteria In The Bayesian Approximate Measurement Invariance: A Simulation Study, Abeer Atallah S. Alamri

USF Tampa Graduate Theses and Dissertations

Measurement invariance (MI) is conducted to ensure that differences found in the results of group comparisons are due to true substantive differences and not methodological artifacts. Previous cross-cultural and cross-national studies with large number of groups showed that the advanced measurement invariance level was rarely held when utilizing the traditional (frequentist) MI approach. The Bayesian approximate measurement invariance (BAMI) was introduced to override the traditional MI strict assumption, because trivial non-invariance in parameters across groups is allowed. Although the concept of the BAMI, which has been utilized since 2013, was incorporated into the context of structural equation modeling, there is …


Time Scavengers: An Educational Website To Communicate Climate Change And Evolutionary Theory To The Public Through Blogs, Web Pages, And Social Media Platforms, Adriane R. Lam, Jennifer E. Bauer, Susanna Fraass, Sarah L. Sheffield, Maggie R. Limbeck, Rose M. Borden, Megan E. Thompson-Munson, Andrew J. Fraass, J. M. Hills, Cameron E. Muskelly, Kyle R. Hartshorn, Raquel Bryant Feb 2019

Time Scavengers: An Educational Website To Communicate Climate Change And Evolutionary Theory To The Public Through Blogs, Web Pages, And Social Media Platforms, Adriane R. Lam, Jennifer E. Bauer, Susanna Fraass, Sarah L. Sheffield, Maggie R. Limbeck, Rose M. Borden, Megan E. Thompson-Munson, Andrew J. Fraass, J. M. Hills, Cameron E. Muskelly, Kyle R. Hartshorn, Raquel Bryant

School of Geosciences Faculty and Staff Publications

Climate change and evolution are topics at the forefront of political discussions, debates, and the public sphere. Regardless of evidence on both topics, the public as a whole still believes they are under debate. It is imperative that the public have access to correct and easy-to-digest information on these topics to make informed environmental and ecological decisions. To date, scientifically accurate digital platforms aimed at informing the public on these topics are overly complex and jargon-ridden. Time Scavengers (www.timescavengers.blog) was created to address these issues and is maintained by a group of academics, graduate students, avocational scientists, and educators. The …


Absorber And Window Study – Cdsexte1-X/Cdte Thin Film Solar Cells, Chih-An Hsu Jan 2019

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 …


Isolution 1.0: An Isotope Evolution Model Describing The Stable Oxygen (Δ18O) And Carbon (Δ13C) Isotope Values Of Speleothems, Michael Deininger, Denis Scholz Jan 2019

Isolution 1.0: An Isotope Evolution Model Describing The Stable Oxygen (Δ18O) And Carbon (Δ13C) Isotope Values Of Speleothems, Michael Deininger, Denis Scholz

International Journal of Speleology

Stable oxygen and carbon isotope ratios (δ13C and δ18O) are the most applied climate and environmental proxies in speleothems allowing to infer past changes in cave drip water δ13C and δ18O related to climate and environmental variations from above the cave. However, disequilibrium isotope fractionation processes can modify δ13C and δ18O values in speleothems, which is in most cases difficult to estimate due to inter-dependencies on various cave specific parameter. To better understand the effect of these disequilibrium isotope fractionation processes proxy system models were developed in recent …


Calculus Application To Topographic Mapping, Veronica Zapata Jan 2019

Calculus Application To Topographic Mapping, Veronica Zapata

Undergraduate Journal of Mathematical Modeling: One + Two

The goal of the paper is to find the volume of water in a ditch. An example image of ditch is given in Appendix C. The first act that before any calculation can be performed is to record the field work. Once at the property the ditch must be identified. Three points of elevations per section should be measured by the surveyor; one point is at the center of the ditch (the lowest point) and the two ones are at the ends (the highest points). The sections are detailed in Appendix A. Using the elevation points from the property, we …


Using The Sir Epidemiology Model With Vector Transmission To Predict The Effectiveness Of A Viral Marketing Campaign And The Spread Of Product Adoption, Michael Freed Jan 2019

Using The Sir Epidemiology Model With Vector Transmission To Predict The Effectiveness Of A Viral Marketing Campaign And The Spread Of Product Adoption, Michael Freed

Undergraduate Journal of Mathematical Modeling: One + Two

Stevelab, LLC is working on an app that will be released within the year. For planning purposes, the company needs to be able to predict how well the app will spread in its initial phase. Because the pilot launch will be limited to Hillsborough County, FL, there is a limited population. The marketing strategy is to sell the application to places where people gather to mingle and socialize, with a particular focus to the bar scene. Customers of the bar can use the app for free. In addition to our direct sales efforts, we can expect the bar owners to …


Equilibrium Ratio Of Polymers To Monomers In Cooperative Polymerization Of Amyloid-Β Protein, Tina Gagliardo Jan 2019

Equilibrium Ratio Of Polymers To Monomers In Cooperative Polymerization Of Amyloid-Β Protein, Tina Gagliardo

Undergraduate Journal of Mathematical Modeling: One + Two

Amyloid-β42 is a protein polymer that catalyzes the formation of pathogenic amyloid plaques that are a prominent feature in the brain tissue of patients who suffer from Alzheimer’s disease. Aβ42 polymerizes via a nucleation-elongation mechanism; several monomers must first congregate into a nucleus before it can elongate into a polymer. The nucleation step is energetically unfavorable since a nucleus smaller than 7 to 8 monomeric units is unstable, therefore the pieces tend to dissociate faster than they can bond together. A solution of Aβ42 will consist of 100% monomers and oligomers smaller than the nucleus when the total concentration is …


Calculating Water Wavelength Using Dispersion Relation And Approximation, Chantelle Lee Jan 2019

Calculating Water Wavelength Using Dispersion Relation And Approximation, Chantelle Lee

Undergraduate Journal of Mathematical Modeling: One + Two

The dispersion relation equation is used to directly compute wave number and wave length to compliment water wave pressure sensor readings. Waves are measured to help coastal engineering to better mitigate coastal infrastructures. Various given wave periods and water depths are used to show how the dispersion relation equation could compute wave length. Also, shallow and deep-water approximations are formulated from the dispersion relation equation and the results are compared.


Effects Of Change In Tire Pressure Upon Efficiency Of A Vehicle, Haider Ali Khan Jan 2019

Effects Of Change In Tire Pressure Upon Efficiency Of A Vehicle, Haider Ali Khan

Undergraduate Journal of Mathematical Modeling: One + Two

The objective of this paper is to compare the difference in the efficiency of acceleration, of a 2018 Audi A8, in two distinct scenarios where the tire pressure is kept at a maximum and partial level. The approach towards solving the issue is multi-faceted, the efficiency is dependent on the difference in the time it takes for the car to accelerate, thus to obtain the elapsed time, the foundational basis is set by the relations between Torque/Force, and RPM/Speed of the vehicle. All the calculations are completed by using the data extracted from the car’s specifications set (Automobile Catalog). Newton’s …


Population And Mortality Predictions Of The Florida Manatee – Ten Year Watercraft Mortality, Dylan Lehigh Jan 2019

Population And Mortality Predictions Of The Florida Manatee – Ten Year Watercraft Mortality, Dylan Lehigh

Undergraduate Journal of Mathematical Modeling: One + Two

The West Indian Manatee is currently listed as a threatened species by the U.S Fish and Wildlife service. A threatened designation means population levels still are at risk of becoming endangered again in the foreseeable future. This project seeks to forecast how many manatees would perish from watercraft strikes (the greatest threat to their survival) based upon the most current method utilized for projecting manatee population growth.

The latest version, known as the Core Biological Model (version 6) or CBMv6, was employed along with the most current manatee population data, which was provided by Dr. Jeffrey A. Hostetler. Dr. Hostetler …


A Mathematical Model For The Upper Limits Of Thyroid Volume In Adolescents, Jacob Treanor Jan 2019

A Mathematical Model For The Upper Limits Of Thyroid Volume In Adolescents, Jacob Treanor

Undergraduate Journal of Mathematical Modeling: One + Two

This paper describes a mathematical model that relates age to the volume of the thyroid gland, given in milliliters, of adolescents based on data from a 1997 study by the World Health Organization (W.H.O.) (World Health Organization, 1997). Using the upper limit per age group provided by the data, a model was constructed through integration of the second derivative of the data for males and females, ages 6-15. It was concluded that the upper limit for the thyroid volume could be expressed by one of two second order polynomial equations, depending on gender, with any values significantly larger than those …


Locating Centers Of Mass With Image Processing, Amina Gahramanova Jan 2019

Locating Centers Of Mass With Image Processing, Amina Gahramanova

Undergraduate Journal of Mathematical Modeling: One + Two

The center of mass of a rigid body is a unique point that represents the mean position of all matter that composes it. Allowing representing complex bodies as a single point, this concept is underlying the basis of all essential mechanical calculations, and is therefore a crucial consideration in engineering. The paper shows how to devise a fast and convenient way of locating the centroid of planar objects of different shapes. For several shapes that can be represented as regions bounded by graphs of functions, this point can be found by using integral calculus. However, solving for the center of …


Using Moment Of Inertia And Observable Planetary Features To Approximate The Two-Layer Structure Of Earth, Jupiter, And Neptune, Selena Kimball Jan 2019

Using Moment Of Inertia And Observable Planetary Features To Approximate The Two-Layer Structure Of Earth, Jupiter, And Neptune, Selena Kimball

Undergraduate Journal of Mathematical Modeling: One + Two

This paper examines the interior structure and composition of Earth, Jupiter, and Neptune by using moment of inertia (MoI) and observable planetary features to create approximate two-layer interior structure models. The moment inertia of a uniform sphere, hollow sphere, and a sphere with a shell are derived to calculate the radius and density variables that identify the relationship between the different radii and densities of the two layers. A two-layer model of the planet’s interior can then be formulated based on the radius, density, known MoI factor and the surface density or the assumed composition density of the planet. The …


Using Matrices To Balance Chemical Reactions And Modeling The Implications Of A Balanced Reaction, Emilee Barrett Jan 2019

Using Matrices To Balance Chemical Reactions And Modeling The Implications Of A Balanced Reaction, Emilee Barrett

Undergraduate Journal of Mathematical Modeling: One + Two

This paper explores an alternative way to balancing equations of chemical reactions and understanding why it is necessary to use balanced equations in science. To balance a chemical equation chemists often guess the coefficients that would balance the equation and check if it works. An alternative method is to use matrices to determine the coefficients of a balanced chemical reaction through solving a system of linear Diophantine equations. After determining the coefficients, a balanced chemical reaction can be formed and used to model how the different coefficients impact the overall reaction. Then it can lead to larger applications within the …


Bicycle Speed Through Different Gears With Drag, Ian Larson Jan 2019

Bicycle Speed Through Different Gears With Drag, Ian Larson

Undergraduate Journal of Mathematical Modeling: One + Two

When riding a bicycle, the rider experiences two forces: the force of the road that acts upon the rear wheel while pedaling, and an opposing force that exerts on the bicycle/cyclist, called aerodynamic drag force (drag). When adjusting Newton’s equation in the second law of motion, the instantaneous change in velocity is equal to the object’s net force divided by its mass. The corresponding differential equation has not been solved analytically. With the bicycle starting at rest at t=0, we solved the equation numerically for any time t by using what is known as Euler’s Method to plot the …


Integrating The Equation Of Hydrostatics For Groundwater Under Non-Isothermal Conditions, Megan A. Levine Jan 2019

Integrating The Equation Of Hydrostatics For Groundwater Under Non-Isothermal Conditions, Megan A. Levine

Undergraduate Journal of Mathematical Modeling: One + Two

Groundwater is an important area of study for several scientific fields and is relevant to many problems in our everyday life. One way the study of groundwater has become different in this age of technology is through modeling. Modeling is used in numerous fields to visualize complex problems and view inaccessible areas, such as under the Earth. An essential part of groundwater modeling is to know water pressure at any depth underground. The difficulty in calculating this is that there are several variables that affect water pressure, all of which are affected by one another and all are calculated by …


Calculating The Electromotive Force Through A Loop, Esteban Leal Jan 2019

Calculating The Electromotive Force Through A Loop, Esteban Leal

Undergraduate Journal of Mathematical Modeling: One + Two

This is a short article which utilizes the equations of Faraday’s law, Ampere’s law, and Ohm’s law. We manipulate the formulas to solve a practical application in which the electromotive force must be calculated. With the successful calculation of the electromotive force, we can use this technique in larger applications.


Acid-Base Titration, David Pierre Jan 2019

Acid-Base Titration, David Pierre

Undergraduate Journal of Mathematical Modeling: One + Two

Titration is an analytical method used in biomedical sciences and analytical chemistry laboratories to determine the quantity or the concentration of a known or unknown substance. There are many kinds of titrations, but this investigation is fundamentally based on acid-base titration, in which the development of a mathematical titration model is explained and determined. In a titration experiment, the concentration and volume of the base added is proportionally equal to those of the acid. The concentration of the substance is determined by following this principle. Moreover, these calculations are usually approximate. Thus, the construction of a titration model is done …


The Sons Report (1989-1994, Mathematical Association Of America): The Way It Was, Linda R. Sons Jan 2019

The Sons Report (1989-1994, Mathematical Association Of America): The Way It Was, Linda R. Sons

Numeracy

Recollections and commentary by Linda R. Sons on a 1994 national report entitled Quantitative Reasoning for College Graduates: A Complement to the Standards. Professor Sons chaired the committee which wrote the report and championed its use.

This paper traces the development of the 1994 MAA report Quantitative Reasoning for College Graduates: A Complement to the Standards--a report which is still surprisingly relevant. The paper highlights some major parts of the report, describing the context in which its conclusions were made. Additionally, it challenges and encourages those continuing the quest for QL in the nation by noting progress made …


Three Formative Questions In The Quantitative Literacy Movement, Dorothy Wallace Jan 2019

Three Formative Questions In The Quantitative Literacy Movement, Dorothy Wallace

Numeracy

In this essay we remember early discussions attempting to answer three questions that played a formative role in our understanding of and approach to numeracy, quantitative literacy, and quantitative reasoning: (1) What is numeracy? (2) Should the QL movement promote any specific kind of pedagogy? (3) What organizational structure will best support QL?

As the QL movement has progressed, these three questions continue to be difficult to answer. As a result, they have been useful formative guides for institutions and organizations seeking to improve the quantitative reasoning of students. Now that the quantitative literacy movement has a firmer standing in …