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Full-Text Articles in Physical Sciences and Mathematics

Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore Aug 2019

Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore

Electronic Theses and Dissertations

Natural caves represent one of the most difficult environments to map with modern 3D technologies. In this study I tested two relatively new methods for 3D mapping in Tipton-Haynes Cave near Johnson City, Tennessee: Structure from Motion Photogrammetry and Computer Vision using Tango, an RGB-D (Red Green Blue and Depth) technology. Many different aspects of these two methods were analyzed with respect to the needs of average cave explorers. Major considerations were cost, time, accuracy, durability, simplicity, lighting setup, and drift. The 3D maps were compared to a conventional cave map drafted with measurements from a modern digital survey instrument …


Algebraic Properties Of Neural Codes., Katie C. Christensen Aug 2019

Algebraic Properties Of Neural Codes., Katie C. Christensen

Electronic Theses and Dissertations

The neural rings and ideals as algebraic tools for analyzing the intrinsic structure of neural codes were introduced by C. Curto, V. Itskov, A. Veliz-Cuba, and N. Youngs in 2013. Since then they have been investigated in several papers, including the 2017 paper by S. G\"unt\"urk\"un, J. Jeffries, and J. Sun, in which the notion of polarization of neural ideals was introduced. We extend their ideas by introducing the polarization of motifs and neural codes, and show that these notions have very nice properties which allow the studying of the intrinsic structure of neural codes of length $n$ via the …


Aerobic Photolysis Mecbl: Structure And Electronic Properties Of Cbl-O-O-Ch3 Intermediate., Aida Bazarganpour Aug 2019

Aerobic Photolysis Mecbl: Structure And Electronic Properties Of Cbl-O-O-Ch3 Intermediate., Aida Bazarganpour

Electronic Theses and Dissertations

The photolysis of methylcobalamin (coenzyme B12) results in homolytic cleavage of the Co-C bond, forming cob(II)alamin and the Co(II)/CH3 radical pair (RP) which further react with O2 to form the intermediate (R-O-O-Cbl) that involves in the aerobic photolysis. It has been suggested that the key intermediate (R-O-O-Cbl) involves in aerobic photolysis is the insertion of O2 between the Co-C bond. Clearly, the exposure of light is needed to induce the activation Co-C bond for generating the Co(II)/CH3 radical pair (RP). The intermediate (R-O-O-Cbl) undergoes further decomposition to aldehyde as the final product of aerobic …


Allee Effects Introduced By Density Dependent Phenology., Timothy James Pervenecki Aug 2019

Allee Effects Introduced By Density Dependent Phenology., Timothy James Pervenecki

Electronic Theses and Dissertations

We consider both the nonspatial model and spatial model of a species that gives birth to eggs at the end of the year. It is assumed that the timing of emergence from eggs is controled by phenology, which is density dependent. In general, the solution maps for our models are implicit; When the solution map is explicit, it is extremely complex and it is easier to work with the implicit map. We derive integral conditions for which the nonspatial model exhibits strong Allee effect. We also provide a necessary condition and a sufficient condition for the existence of positive equilibrium …


Novel Bayesian Methodology In Multivariate Problems., Debamita Kundu Aug 2019

Novel Bayesian Methodology In Multivariate Problems., Debamita Kundu

Electronic Theses and Dissertations

This dissertation involves developing novel Bayesian methodology for multivariate problems. In particular, it focuses on two contexts: shrinkage based variable selection in multivariate regression and simultaneous covariance estimation of multiple groups. Both these projects are centered around fully Bayesian inference schemes based on hierarchical modeling to capture context-specific features of the data and the development of computationally efficient estimation algorithm. Variable selection over a potentially large set of covariates in a linear model is quite popular. In the Bayesian context, common prior choices can lead to a posterior expectation of the regression coefficients that is a sparse (or nearly sparse) …


A Study Of Big Field Multivariate Cryptography., Ryann Cartor Aug 2019

A Study Of Big Field Multivariate Cryptography., Ryann Cartor

Electronic Theses and Dissertations

As the world grapples with the possibility of widespread quantum computing, the cryptosystems of the day need to be up to date. Multivariate Public Key Cryptography is a leading option for security in a post quantum society. One goal of this work is to classify the security of multivariate schemes, especially C*variants. We begin by introducing Multivariate Public Key Cryptography and will then discuss different multivariate schemes and the main types of attacks that have been proven effective against multivariate schemes. Once we have developed an appropriate background, we analyze security of different schemes against particular attacks. Specifically, we …


Characterizing Majority Rule On Various Discrete Models Of Consensus., Trevor Leach Aug 2019

Characterizing Majority Rule On Various Discrete Models Of Consensus., Trevor Leach

Electronic Theses and Dissertations

In any social structure, there is often a need to reach decisions, not only within a group but between groups as well, sometimes even urgently so. Each of the individuals constituting these groups has their own preference for the decision to be made. We will discuss the problem of aggregating individual preferences into a collective preference and under what conditions we are required to select a collective majority. In this dissertation we will look at three models of consensus and show the conditions vary based on the model.


Electrodeposition Of Hydrogen Molybdenum Bronze Films And Electrochemical Reduction Of Carbon Dioxide At Low Over Potentials, Sami Alharbi Aug 2019

Electrodeposition Of Hydrogen Molybdenum Bronze Films And Electrochemical Reduction Of Carbon Dioxide At Low Over Potentials, Sami Alharbi

Electronic Theses and Dissertations

Hydrogen molybdenum oxide, known has molybdenum bronze, is a material of interest due to catalyzing electron transfer reactions. Specifically, molybdenum bronze is an electrocatalyst toward carbon dioxide reduction. Electrochemical deposition from a peroxymolybdic acid solution is a method for preparing molybdenum bronze films. This work demonstrates reproducible electrodeposition on indium tin oxide substrates and conductive carbon paper. Film thickness depends on concentration, time and pH. After characterization by film thickness, resistance, XRD and XPS, the as deposited films served as the working electrode for electrochemical reduction of carbon dioxide in 0.1 M NaHCO3. Ion chromatography determined formate resulting …


Debris-Slide Susceptibility Modelling Using Gis Technology In The Great Smoky Mountains National Park, Raja Das Aug 2019

Debris-Slide Susceptibility Modelling Using Gis Technology In The Great Smoky Mountains National Park, Raja Das

Electronic Theses and Dissertations

Debris-slides are one of the most frequently occurring geological hazards in metasedimentary rocks of the Anakeesta ridge in Great Smoky Mountains National Park (GRSM), which often depends on the influence of multiple causing factors or geo-factors such as geological structures, slope, topographic elevation, land use, soil type etc. or a combination of these factors. The main objective of the study was to understand the control of geo-factors in initiating debris-slides using different knowledge and data-driven methods in GIS platform. The study was performed in three steps: (1) Evaluation of geometrical relationship between geological discontinuity and topographic orientation in initiation of …


Investigation Of Student Understanding Of Implicit Differentiation, Connor Chu Aug 2019

Investigation Of Student Understanding Of Implicit Differentiation, Connor Chu

Electronic Theses and Dissertations

Challenges that students face in first semester calculus have been found to be a factor in high attrition rates of students from science, technology, engineering, and mathematics (STEM) majors. With an increase in the demand for STEM graduates, an attempt must be made to remedy this issue. Research has shown that students have difficulties with many topics in the realm of calculus. Of these, students have been found to struggle with the concept of derivative and ideas related to it. However, some derivative topics have not been examined as thoroughly as others. Implicit differentiation, a technique that allows us to …


Evaluating Fluid Fluxes From Deep-Sea Seepage Habitats, Leigha E. Peterson Jul 2019

Evaluating Fluid Fluxes From Deep-Sea Seepage Habitats, Leigha E. Peterson

Electronic Theses and Dissertations

The permanently dark deep-sea, located at oceanic water depths greater than 200 m, represents the largest potential habitat space on Earth. The physicochemical conditions of the planet’s largest biome are tightly coupled to the exchange of matter and energy from terrestrial and sea-floor end-members. In fact, global ocean and climate systems are significantly impacted by deep-sea processes. Seafloor vents and seeps appear to act as geologic exchange conduits, returning recycled materials to the hydrosphere to sustain another generation of life. Despite submarine seepage having control on global elemental cycling, it is estimated that less than 1% of the deep-sea has …


An Epidemiological Model With Simultaneous Recoveries, Ariel B. Farber Jun 2019

An Epidemiological Model With Simultaneous Recoveries, Ariel B. Farber

Electronic Theses and Dissertations

Epidemiological models are an essential tool in understanding how infection spreads throughout a population. Exploring the effects of varying parameters provides insight into the driving forces of an outbreak. In this thesis, an SIS (susceptible-infectious-susceptible) model is built partnering simulation methods, differential equations, and transition matrices with the intent to describe how simultaneous recoveries influence the spread of a disease in a well-mixed population. Individuals in the model transition between only two states; an individual is either susceptible — able to be infected, or infectious — able to infect others. Events in this model (infections and recoveries) occur by way …


Development Of Bismuth Oxyhalide Photocatalysts For Environmental And Industrial Applications, Robert Arthur May 2019

Development Of Bismuth Oxyhalide Photocatalysts For Environmental And Industrial Applications, Robert Arthur

Electronic Theses and Dissertations

Heterogeneous semiconductor photocatalysis, of interest for water splitting and environmental remediation applications, uses light to drive reactions. Metal oxide and sulfide semiconductors have been previously studied but have limitations that include large band gap energies and high rates of recombination. Bismuth oxyhalides (BiOX) are an emerging class of photocatalysts with tunable band gaps and low rates of recombination due to their unique crystal structures. Studies of BiOX photocatalytic activity have largely focused on removal of azo dyes from aqueous solutions, with little attention paid to degradation byproducts. Furthermore, these catalysts have not been explored as a means to conduct organic …


Paper Structure Formation Simulation, Tyler R. Seekins May 2019

Paper Structure Formation Simulation, Tyler R. Seekins

Electronic Theses and Dissertations

On the surface, paper appears simple, but closer inspection yields a rich collection of chaotic dynamics and random variables. Predictive simulation of paper product properties is desirable for screening candidate experiments and optimizing recipes but existing models are inadequate for practical use. We present a novel structure simulation and generation system designed to narrow the gap between mathematical model and practical prediction. Realistic inputs to the system are preserved as randomly distributed variables. Rapid fiber placement (~1 second/fiber) is achieved with probabilistic approximation of chaotic fluid dynamics and minimization of potential energy to determine flexible fiber conformations. Resulting digital packed …


New Methodologies For Examining And Supporting Student Reasoning In Physics, John C. Speirs May 2019

New Methodologies For Examining And Supporting Student Reasoning In Physics, John C. Speirs

Electronic Theses and Dissertations

Learning how to reason productively is an essential goal of an undergraduate education in any STEM-related discipline. Many non-physics STEM majors are required to take introductory physics as part of their undergraduate programs. While certain physics concepts and principles may be of use to these students in their future academic careers and beyond, many will not. Rather, it is often expected that the most valuable and longlasting learning outcomes from a physics course will be a repertoire of problem-solving strategies, a familiarity with mathematizing real-world situations, and the development of a strong set of qualitative inferential reasoning skills.

For more …


Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias May 2019

Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias

Electronic Theses and Dissertations

Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To …


Optical Memory Behavior, Metallophilic Luminescence, And Chemical Sensing Ability Of Inorganic And Organometallic Complexes: Development Of Optoelectronic Materials, Aaron D. Nicholas May 2019

Optical Memory Behavior, Metallophilic Luminescence, And Chemical Sensing Ability Of Inorganic And Organometallic Complexes: Development Of Optoelectronic Materials, Aaron D. Nicholas

Electronic Theses and Dissertations

This dissertation is divided into three sections: (1) optical memory, (2) metallophilic-based luminescence, and (3) chemical sensors. (1) Optical memory behavior of d10metal Cu(I) thiocyanate salts are investigated to explore their potential use in the development of digital data storage devices. From this study we have discovered a new class of CuSCN(3-BrPy)2optical memory material which undergo a reduction in emission intensity upon laser irradiation. This loss of emission intensity can be reversed simply by heating the sample to room temperature. The mechanism by which this emission loss occurs has been studied, revealing a migrating Br atom …


Nontraditional Hydrogen Bonding In Asymmetric Lewis Acid Catalysis, Brandon Vernier May 2019

Nontraditional Hydrogen Bonding In Asymmetric Lewis Acid Catalysis, Brandon Vernier

Electronic Theses and Dissertations

In the field of asymmetric induction, there is a shift from the synthesis of reaction

specific chiral auxiliaries towards a broader mechanistic approach. Our approach is to

develop a theory of asymmetric catalyst design from first principles. The Diels-Alder

reaction of 2-methacrolein and 1,3-cyclopentadiene in the presence of 15 mole % lmenthoxy

aluminum dichloride, reported by Koga, achieved the (S)-exo-Diels-Alder

cycloadduct with 72% ee (0% ee Endo for acrolein). The dramatic change from 72% to 0%

ee is a significant fact that has been overlooked in practical organic synthesis.

In the first phase of this work, the conformational landscape of …


The Effects Of Constructed Wetlands On Metal Solubilization And Bioavailability In Passive Mine Remediation, Elizabeth Cochran May 2019

The Effects Of Constructed Wetlands On Metal Solubilization And Bioavailability In Passive Mine Remediation, Elizabeth Cochran

Electronic Theses and Dissertations

The legacy of coal mining in Appalachia has left many watersheds impacted by abandoned mine drainage. The drainage degrades streams, groundwater and habitats with acidity and toxic heavy metals. The Lowber Passive Remediation System has been in operation since 2004 to remediate high amounts of dissolved Fe, SO4, Al, and Mn. The site consists of six settling ponds and an extensive wetlands at the finish. This study investigated the resolubilization of Fe and Mn in the wetlands and the role of bacteria in resolubilization. During three seasons, field measurements of water quality and lab analysis of Fe, Mn, …


Water Quality Assessment Of Deer Lakes County Park Before, During And After Unconventional Shale Gas Drilling, Daniel Robinson May 2019

Water Quality Assessment Of Deer Lakes County Park Before, During And After Unconventional Shale Gas Drilling, Daniel Robinson

Electronic Theses and Dissertations

Allegheny County, Pennsylvania, signed a lease to allow unconventional natural gas extraction from Marcellus Shale beneath Deer Lakes County Park in 2014. The park has three man-made lakes and four waterways that eventually flow into the Allegheny River. Drilling commenced in early 2016, and there are now five producing wells. The park has an extensive abandoned coal mine network and several abandoned oil and gas wells. Thus, an independent water quality study was undertaken beginning in July 2015. Samples from seven different sites in the park were used to establish a water quality baseline prior to the drilling. Monthly sampling …


Unconventional Gas Extraction In Southwestern Pennsylvania: Complaints, Production, And Water Quality, Dannielle Pratt May 2019

Unconventional Gas Extraction In Southwestern Pennsylvania: Complaints, Production, And Water Quality, Dannielle Pratt

Electronic Theses and Dissertations

The dramatic rise in unconventional oil and gas extraction in Pennsylvania has presented a challenge to the Pennsylvania Department of Environmental Protection in managing regulatory required data, and the uniformity of public access via their online databases. This study analyzed over a decade of all the oil and gas complaints and unconventional gas production in Washington County. Of the 1,811 wells drilled between 2004 and 2018, 1,683 are producing, 74 are plugged, 52 regulatory inactive, and 2 abandoned. The PADEP received 10,389 complaints from 2004 to 2018. Only 2,420 of 4,489 water quality complaints were resolved within the legally required …


Unconventional Oil And Gas Extraction In Ohio: Regulations, Production And Water Quality, Brittany Garman May 2019

Unconventional Oil And Gas Extraction In Ohio: Regulations, Production And Water Quality, Brittany Garman

Electronic Theses and Dissertations

The Utica shale play is the main target for unconventional oil and gas extraction in Ohio. Over 2,000 wells have been drilled since the first in 2011. This rapid expansion has led to concerns over the availability of information and potential environmental impacts. An assessment of readily available data was done through an examination of the ODNR website for oil and gas regulations, permits, spud and completion reports, water usage and waste data, and complaints, as well as brine and de-icer application. Water quality testing of an exceptional warm water tributary in the Captina Creek watershed in Belmont County, Ohio …


Synthesis, Characterization And Crystal Growth Of I2-Ii-Iv-Vi4 And I4-Ii-Iv2-Vi7 Diamond-Like Semiconductors With Potential In Ir-Nlo Applications, Jennifer Glenn May 2019

Synthesis, Characterization And Crystal Growth Of I2-Ii-Iv-Vi4 And I4-Ii-Iv2-Vi7 Diamond-Like Semiconductors With Potential In Ir-Nlo Applications, Jennifer Glenn

Electronic Theses and Dissertations

In this dissertation, several new and existing diamond-like semiconductors (DLSs) were synthesized and investigated for their potential in infrared nonlinear optical (IR-NLO) applications. In Chapter 2 growth of large single crystals of Li2MnGeS4 was carried out using iodine vapor transport and a newly created graphite-tube containment system. This crystallization method produced sizable single crystals on the scale of 2x1x1 mm3, that were used to determine the material’s magnetic properties. Magnetization data indicate that the compound is antiferromagnetic with a Néel temperature of 10 K and an effective magnetic moment of 5.6 /f.u.. The specific heat …


Learning Science: Physical And Life Sciences In Curricula Across U.S. Schools Of Nursing, Valerie C. Sauda May 2019

Learning Science: Physical And Life Sciences In Curricula Across U.S. Schools Of Nursing, Valerie C. Sauda

Electronic Theses and Dissertations

Nursing educators are being challenged to provide curriculum that meets the changing healthcare environment and demand for creative, innovative nurses to assist in transforming healthcare into the future (Benner, Sutphen, Leonard, & Day, 2010; Institute Of Medicine, 2011). The liberal education provided within a baccalaureate of science in nursing (BSN) degree program provides a diversity of courses within the curriculum, including courses in the natural, physical, mathematical, and social sciences (American Association of Colleges of Nursing [AACN], 2008). Although nursing programs have included science courses in curriculum since the early 1900s (Nutting & Dock, 1907), there is lack of nursing …


Climate-Driven Migration: Prioritizing Cultural Resources Threatened By Secondary Impacts Of Climate Change, Frankie St. Amand May 2019

Climate-Driven Migration: Prioritizing Cultural Resources Threatened By Secondary Impacts Of Climate Change, Frankie St. Amand

Electronic Theses and Dissertations

Archaeological sites suffer increasingly destructive primary impacts of climate-driven natural hazards, including sea level rise, flooding, and erosion. Action is generally limited to mitigation and salvage of immediately threatened sites, with little attention or forethought given to secondary effects, such as destruction of interior archaeological resources by inland migration of affected populations. The United Nations predicts a growing trend in resettlement of climate-affected communities from areas where in-situ infrastructure adaptations are not economically feasible, legal, or physically possible. While adapting existing urban infrastructure (e.g., abating combined sewage overflows) is a viable option in the primary impact zone (e.g. coastal areas …


Luminescence Antenna Behavior In Lanthanide Complexes And Luminescence Sensing In Group 11 Iodides, Francis Barnes May 2019

Luminescence Antenna Behavior In Lanthanide Complexes And Luminescence Sensing In Group 11 Iodides, Francis Barnes

Electronic Theses and Dissertations

In this thesis luminescent materials are studied. The luminescent materials studied are lanthanide complexes and group 11 iodide sensing abilities. Emission intensity of the lanthanide complexes through direct excitation of the lanthanide ion are relatively weak. To overcome this, three unique organic ligands were utilized to synthesize lanthanide nitrate complexes in which higher emission intensity can be observed via the antenna effect. Increased emission intensity resulted for EuIII and TbIII complexes for each ligand except triphenylphosphane oxide (only the TbIII complex demonstrated increased emission intensity). Latva’s empirical rule allows for the antenna effect to occur, in which …


Valuing The Economic Benefits Of Conservation Lands In Downeast Maine, Lesley Lichko May 2019

Valuing The Economic Benefits Of Conservation Lands In Downeast Maine, Lesley Lichko

Electronic Theses and Dissertations

Natural ecosystems provide numerous benefits that contribute to humans and the economy, including market goods such as timber and forest products, as well as benefits that are not directly measured in the marketplace, such as wildlife habitat provision and recreational provision. These benefits are collectively known as ecosystem services. Natural ecosystems are under significant pressure to be converted to other uses from factors such as shifts in ownership, land use change, fragmentation and climate change. To counter these effects, and to protect ecosystem services, public and private entities have worked to place land in conservation; however, conservation is often controversial …


Tide And Storm Surge Dynamics In Estuaries Of Variable Morphology, Preston Spicer May 2019

Tide And Storm Surge Dynamics In Estuaries Of Variable Morphology, Preston Spicer

Electronic Theses and Dissertations

Storm surges are the most destructive component of coastal storms, and climate change is predicted to enhance the frequency of intense storm events in the future. Currently, most storm surge forecasting assumes linear surges and the extent to which this assumption leads to model inaccuracies is currently unknown. The goals of this research are to characterize storm surge in estuaries and determine the contribution of nonlinear tide-surge interaction to total inland surges. A citizen science experiment was conducted in four estuaries in Maine. Results show the estuary shape influences surges through convergence, friction and man-made constrictions. These mechanisms modified total …


450degree C Aln Thin Film Growth On Nitrided C-Plane Sapphire Substrates, Roger Eastman Feeley May 2019

450degree C Aln Thin Film Growth On Nitrided C-Plane Sapphire Substrates, Roger Eastman Feeley

Electronic Theses and Dissertations

Low temperature (LT) growth of strongly textured AlN by molecular beam epitaxy (MBE) has not been extensively investigated. The low mobility of Al adatoms provides a challenge for growth of AlN at low temperatures (<600 >°C). Consequently, AlN growth by MBE is typically at temperatures >700 °C. Growth at these temperatures can limit the selection of substrates and materials to grow with the AlN. Highly oriented, LT AlN thin films (<50 >nm) were grown on c-­‐plane sapphire, using an interrupted growth procedure. Films were grown by periodically interrupting the Al flux with a nitridation. This two-­‐step cycle was repeated until …


A 2000 Year Saharan Dust Event Record From A European Alps Ice Core, Heather Clifford May 2019

A 2000 Year Saharan Dust Event Record From A European Alps Ice Core, Heather Clifford

Electronic Theses and Dissertations

Ice core archives provide the most direct and detailed evidence of past climate and atmospheric conditions, however, traditional ice core sampling (~1-cm resolution) does not provide significant environmental detail in low accumulation and compressed ice core sites. Advances in ice core sampling techniques allows for the capability to detect environmental signals in compressed ice found deeper in the core using finer sampling resolutions. Using the Climate Change Institute’s W.M. Keck Laser Ice Facility non-destructive, ultra-high-resolution, continuously sampled laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS) sampling on ice cores, we are able to resolve proxies for both climatological and meteorological scale events …