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2021

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Articles 301 - 330 of 27876

Full-Text Articles in Physical Sciences and Mathematics

Salt Marshes As Groundwater Buffers For Development: A Survey Of South Carolina Salt Marsh Basins, Alicia M. Wilson, Meghan Shanahan, Erik M. Smith Dec 2021

Salt Marshes As Groundwater Buffers For Development: A Survey Of South Carolina Salt Marsh Basins, Alicia M. Wilson, Meghan Shanahan, Erik M. Smith

Faculty Publications

Salt marshes serve as zones of intense groundwater mixing and reaction between freshwater uplands and estuaries. This raises the question of whether the impacts of upland development on nutrient and carbon species can be transmitted through salt marshes via groundwater, or whether salt marshes can buffer estuarine waters from coastal development. We sampled groundwater from fifteen tidal creek basins in South Carolina to test for compositional differences associated with development and marsh width. Groundwater samples from near creekbanks and below freshwater uplands were analyzed for salinity, total dissolved nitrogen and phosphorus, and dissolved organic carbon. Analyses revealed significantly higher TDN …


Predicting Stocks With Lstm-Based Drnn And Gan, Duy Ngo Dec 2021

Predicting Stocks With Lstm-Based Drnn And Gan, Duy Ngo

Master's Projects

Trading equities can be very lucrative for some and a gamble for others. Professional traders and retail traders are constantly amassing information to be a step ahead of the market to profit off the value of stocks on the market. Some of the tools in their arsenal include different types of calculations based on a variety of data collected on a stock. Technical analysis is a technique for traders to analyze the data of equities presented on charts. Often, the way the price changes over time can be used as an indicator for traders to predict how future prices will …


Ecological Exposure And Effects Of Microplastics In Crabs Along The Pacific Coast, Dorothy A. Horn Dec 2021

Ecological Exposure And Effects Of Microplastics In Crabs Along The Pacific Coast, Dorothy A. Horn

Dissertations and Theses

Microplastics have been documented across the global oceans as an ubiquitous pollutant. Found in the water column, sediment, shorelines, estuaries, freshwater streams and rivers along with terrestrial soils, flora and fauna. The continuous input of plastic waste into the marine environment doesn't seem to be slowing as the amount of plastic created each year increases globally.

This study investigated (1) the effects of microplastic ingestion in the indicator species, the Pacific mole crab (Emerita analoga), testing the predator avoidance behavior, reproductive output and parasitism effects when an adult female gravid crab had ingested microplastics (2) adult mortality, hatching …


Management Of Meadow Fescue Pasture For High-Producing Dairy Cows In Northern Japan, K. Sudo, K. Ochiai, T. Ikeda Dec 2021

Management Of Meadow Fescue Pasture For High-Producing Dairy Cows In Northern Japan, K. Sudo, K. Ochiai, T. Ikeda

IGC Proceedings (1993-2023)

The objective of this study was to establish an intensive grazing system of meadow fescue (Festuca elatior L.) pasture for high-producing dairy cows in some areas of Japan where soil freezes in winter. Plant succession of meadow fescue pastures that had been grazed at different plant heights and milk production from cows grazed on meadow fescue pasture compared to that from cows grazed on perennial ryegrass pasture were surveyed over a five year period. Succession of meadow fescue pasture depended on the management of plant height before grazing use. Milk production from cows grazed on meadow fescue pasture was …


Leaf Blade Selection By Sheep In Kleingrass (Panicum Coloratum L.) Pastures With Different Deferment Periods, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri Dec 2021

Leaf Blade Selection By Sheep In Kleingrass (Panicum Coloratum L.) Pastures With Different Deferment Periods, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1993-2023)

The winter use of standing dead biomass produced by warm season grasses during the previous growing season may be an alternative to grazing systems in the semi-arid Pampean Region of Argentina. This study evaluated: 1) the effect of different deferment periods on the leaf blade percentage and quality of ‘kleingrass’ (Panicum coloratum L.), a warm season specie recently introduced to that region, and 2) whether rams grazing the vegetation accumulated during these different periods are able to select leaf blades to maintain the quality of their diets. It was generated three treatments by deferment of the forage produced after …


Microhistological Estimation Of Leaf Blade Percentage In Diets From Monoespecific Pastures, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri Dec 2021

Microhistological Estimation Of Leaf Blade Percentage In Diets From Monoespecific Pastures, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1993-2023)

Although a decrease in the leaf-stem ratio affects the nutritive value of pastures, herbivores can reinforce selection for leaf blades to maintain the quality of their diets. This study evaluated whether the percentage of fragments with furrows in blades could be used to estimate the relative intake of this part of the leaves by herbivores grazing monoespecific pastures. It was worked with vegetation of kleingrass (Panicum coloratum L.) from paddocks with three deferment periods. Blade samples, and different plant part mixtures hand compounded were in vitro digested. The digestion residues were microhistological analyzed determining the number of fragment with …


Evaluation Of Kentucky Bluegrass (Poa Pratensis L.) For Creating Sustainable Grazing Swards In Hokkaido, T. Saigusa, S. Tejima, Y. Ogawa, S. Takahashi Dec 2021

Evaluation Of Kentucky Bluegrass (Poa Pratensis L.) For Creating Sustainable Grazing Swards In Hokkaido, T. Saigusa, S. Tejima, Y. Ogawa, S. Takahashi

IGC Proceedings (1993-2023)

Kentucky bluegrass (Poa pratensis L.) is generally considered to be a weed in the meadows of Hokkaido. However, a revaluation of this species should be undertaken in terms of its useful characteristics for labor-saving management on farms in marginal areas. The performance of steers (Holstein-Friesian) and botanical composition of Kentucky bluegrass swards were investigated under the stocking methods of set and rotational grazing and compared with timothy (Phleum pratense L.) swards. Kentucky bluegrass was stable over the grazing season under both methods, although timothy decreased rapidly. The average daily gain of steers raised on Kentucky bluegrass swards was …


Finland, A Package Deal: Disciplinary Climate In Science Classes, Science Dispositions And Science Literacy, Larry J. Grabau, Jari Levonen, Kalle Juuti Dec 2021

Finland, A Package Deal: Disciplinary Climate In Science Classes, Science Dispositions And Science Literacy, Larry J. Grabau, Jari Levonen, Kalle Juuti

Plant and Soil Sciences Faculty Publications

Finland’s educational prowess, though tempered by recent international assessments, has remained intact. This report focused on lessons that could be learned regarding secondary-level science education from the Program for International Student Assessment (PISA) 2015, science-focused assessment. That PISA iteration included not only science literacy but also students’ science dispositions (epistemology, enjoyment, interest, and self-efficacy) and the schools’ science climate measures (disciplinary climate and teaching support). Due to the hierarchical nature of the PISA data, multilevel models were employed in this Finnish study, involving 5582 students from 167 schools. Science dispositions (as outcome measures) were differently associated with teaching support and …


Investigation Of The Effect Of Fly Ash Released From Kütahya Thermal Power Plants By Using Remote Sensing Methods, Güzide Kalyoncu Ergüler, Fatma Melis Bayindir, Ayşe Dağliyar Dec 2021

Investigation Of The Effect Of Fly Ash Released From Kütahya Thermal Power Plants By Using Remote Sensing Methods, Güzide Kalyoncu Ergüler, Fatma Melis Bayindir, Ayşe Dağliyar

Bulletin of the Mineral Research and Exploration

In order to determine the long-term effect of thermal power plants, the satellite images of Seyitömer and Tunçbilek Thermal Power Plants and their vicinities were analyzed by using the software of ERDAS IMAGINE v9.1 and PCI Geomatica 2017. The normalized difference vegetation index (NDVI) was determined by using red and near-infrared bands of Landsat satellite images, and areas containing vegetation were revealed in the images. In order to obtain the temporal change in the vegetation areas, the relevant image change detection analysis was applied and the one-year and thirty-year temporal change of vegetation cover is for r = 4 km, …


Metasurfaces For Nano-Illumination In Lidar And Lighting Applications, Sehyeon Kim Dec 2021

Metasurfaces For Nano-Illumination In Lidar And Lighting Applications, Sehyeon Kim

Graduate Theses - Physics and Optical Engineering

The development of a non-scanning laser-based imaging lidar system based on a diffractive optical element with potential applications in advanced driver assistance systems, autonomous vehicles, drone navigation, and mobile devices is reported. The proposed lidar utilizes image processing with homography. The emphasis in the design approach has been on compactness and cost of the final system for it to be deployable both as standalone or complementary to existing lidar sensors, enabling fusion sensing in the applications. This work describes the basic elements of the proposed lidar system. It presents the potential ranging mechanisms, along with their experimental results demonstrating the …


Extending The Quality Of Secure Service Model To Multi-Hop Networks, Paul M. Simon, Scott R. Graham Dec 2021

Extending The Quality Of Secure Service Model To Multi-Hop Networks, Paul M. Simon, Scott R. Graham

Faculty Publications

Rarely are communications networks point-to-point. In most cases, transceiver relay stations exist between transmitter and receiver end-points. These relay stations, while essential for controlling cost and adding flexibility to network architectures, reduce the overall security of the respective network. In an effort to quantify that reduction, we extend the Quality of Secure Service (QoSS) model to these complex networks, specifically multi-hop networks. In this approach, the quantification of security is based upon probabilities that adversarial listeners and disruptors gain access to or manipulate transmitted data on one or more of these multi-hop channels. Message fragmentation and duplication across available channels …


Piezoelectricity In Hafnia, Sangita Dutta, Pratyush Buragohain, Sebastjan Glinsek, Claudia Richter, Hugo Aramberri, Haidong Lu, Uwe Schroeder, Emmanuel Defay, Alexei Gruverman, Jorge Íñiguez Dec 2021

Piezoelectricity In Hafnia, Sangita Dutta, Pratyush Buragohain, Sebastjan Glinsek, Claudia Richter, Hugo Aramberri, Haidong Lu, Uwe Schroeder, Emmanuel Defay, Alexei Gruverman, Jorge Íñiguez

Department of Physics and Astronomy: Faculty Publications

Because of its compatibility with semiconductor-based technologies, hafnia (HfO2) is today’s most promising ferroelectric material for applications in electronics. Yet, knowledge on the ferroic and electromechanical response properties of this all-important compound is still lacking. Interestingly, HfO2 has recently been predicted to display a negative longitudinal piezoelectric effect, which sets it apart from classic ferroelectrics (e.g., perovskite oxides like PbTiO3) and is reminiscent of the behavior of some organic compounds. The present work corroborates this behavior, by first-principles calculations and an experimental investigation of HfO2 thin films using piezoresponse force microscopy. Further, the simulations …


“Transitioning Organisations From A Data Quagmire To Knowledge Nirvana Through The Digital Thread”, David Twohig, Barry Heavey Dec 2021

“Transitioning Organisations From A Data Quagmire To Knowledge Nirvana Through The Digital Thread”, David Twohig, Barry Heavey

Level 3

Historically, organisations have managed product data in a combination of Microsoft Office, Sharepoint and Document Management Systems. In this paper, we explore how different technologies can be leveraged to create digital product profiles, and in doing so structure data to enable effective knowledge management.


Interfacial Engineering And Photoelectrochemistry Of Patterned Metal/Semiconductor Heterostructures, Che Tan Dec 2021

Interfacial Engineering And Photoelectrochemistry Of Patterned Metal/Semiconductor Heterostructures, Che Tan

McKelvey School of Engineering Theses & Dissertations

Photoelectrochemical (PEC) cells enable the conversion of solar energy into storable fuels, which is critical in overcoming the intermittent nature of this largest renewable source. However, the majority of semiconductors used as photoelectrodes in these cells have low conversion efficiencies and/or stabilities. Silicon (Si) is an attractive semiconductor material for photoelectrodes, but the development of efficient Si-based photoanodes is challenging due to their instability in alkaline solutions. Thus, one focus of this dissertation is the design and fabrication of highly stable nickel (Ni)-patterned Si photoanodes through interfacial engineering of the barrier heights. Recently, hot carriers in plasmonic metal nanostructures have …


Deep Convolutional Neural Networks For Accurate Diagnosis Of Covid-19 Patients Using Chest X-Ray Image Databases From Italy, Canada, And The Usa, Amgad A. Salama, Samy H. Darwish, Samir M. Abdel-Mageed, Radwa A. Meshref, Ehab I. Mohamed Dec 2021

Deep Convolutional Neural Networks For Accurate Diagnosis Of Covid-19 Patients Using Chest X-Ray Image Databases From Italy, Canada, And The Usa, Amgad A. Salama, Samy H. Darwish, Samir M. Abdel-Mageed, Radwa A. Meshref, Ehab I. Mohamed

The University of Louisville Journal of Respiratory Infections

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), famously known as COVID-19, has quickly become a global pandemic. Chest X-ray (CXR) imaging has proven reliable, fast, and cost-effective for identifying COVID-19 infections, which proceeds to display atypical unilateral patchy infiltration in the lungs like typical pneumonia. We employed the deep convolutional neural network (DCNN) ResNet-34 to detect and classify CXR images from patients with COVID-19 and Viral Pneumonia and Normal Controls.

Methods: We created a single database containing 781 source CXR images from four different international sub-databases: the Società Italiana di Radiologia Medica e Interventistica (SIRM), the GitHub Database, the …


Comparison Of Major Cloud Providers, Justin Berman Dec 2021

Comparison Of Major Cloud Providers, Justin Berman

Other Student Works

This paper will compare the following major cloud providers: Microsoft Azure, Amazon AWS, Google Cloud, and IBM Cloud. An introduction to the companies and their history, fundamentals and services, strengths and weaknesses, costs, and their security will be discussed throughout this writing.


Dark Energy At Early Times And Act Data: A Larger Hubble Constant Without Late-Time Priors, V. Poulin, Tristan L. Smith, A. Bartlett Dec 2021

Dark Energy At Early Times And Act Data: A Larger Hubble Constant Without Late-Time Priors, V. Poulin, Tristan L. Smith, A. Bartlett

Physics & Astronomy Faculty Works

Recent observations using the Atacama Cosmology Telescope (ACT) have provided ground-based cosmic microwave background (CMB) maps with higher angular resolution than the Planck satellite. These have the potential to put interesting constraints on models resolving the “Hubble tension.” In this paper we fit two models of early dark energy (EDE) (an increase in the expansion rate around matter/radiation equality) to the combination of ACT data with large-scale measurements of the CMB either from the WMAP or the Planck satellite (including lensing), along with measurements of the baryon acoustic oscillations and uncalibrated supernovae luminosity distance. We study a phenomenological axionlike potential …


M-Subharmonic Functions On The Projective Space PN, Gokhan Gogus, Azimbay Sadullaev Dec 2021

M-Subharmonic Functions On The Projective Space PN, Gokhan Gogus, Azimbay Sadullaev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

We consider a class of quasi m-subharmonic functions in the projective space ℙn. Similarly to the m-subharmonic functions, we will show a number of potential properties of quasi m-subharmonic functions. We introduce the concepts of Green’s function Vqm*(z,K,ℙn), ��m-measure ωqm*(z,E,D) and study m-regularities of compact sets K ⊂ ℙn. In contrast to the complex space ℂn, we will prove that in the projective space ℙn the locally …


Odu Research Is Showcased In ‘Waters Rising’ Exhibition At The Chrysler Museum Of Art, Amber Kennedy Dec 2021

Odu Research Is Showcased In ‘Waters Rising’ Exhibition At The Chrysler Museum Of Art, Amber Kennedy

News Items

No abstract provided.


Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang Dec 2021

Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang

Geoscience Faculty Research

The Yangzhuang iron deposit is a Kiruna-type iron oxide-apatite (IOA) deposit within the Ningwu mining district of the Middle and Lower Yangtze River Metallogenic Belt (MLYRMB), China. This study applies a numerical modeling approach to identify the key processes associated with the formation of the deposit that cannot be easily identified using traditional analytical approaches, including the duration of the mineralizing process and the genesis of iron orebodies within intrusions associated with the deposit. This approach highlights the practical value of numerical modeling in quantitatively analyzing mineralizing processes during the formation of mineral deposits and assesses how these methods can …


Difference Schemes Of High Accuracy For Equation Of Spin Waves In Magnets, Mirsaid Aripov, Dauletbay Utebaev, Zhusipbay Nurullaev Dec 2021

Difference Schemes Of High Accuracy For Equation Of Spin Waves In Magnets, Mirsaid Aripov, Dauletbay Utebaev, Zhusipbay Nurullaev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

Three-parameter difference schemes of the finite element method with a high order of accuracy are considered in the article for a mathematical model of spin waves in magnets (Sobolev-type equations). Discretization of time and space variables is conducted on the basis of the finite element method. The parameters of the scheme allow choosing the best approximation and accuracy, and an economic algorithm for numerical implementation. Theorems on the stability and convergence of the considered difference schemes are obtained.


Interpretation Of De Sitter Space Of Second Kind, Abdulaziz Artikbaev, Botirjon Mamadaliyev Dec 2021

Interpretation Of De Sitter Space Of Second Kind, Abdulaziz Artikbaev, Botirjon Mamadaliyev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

In a five-dimensional pseudo-Euclidean space of index two, the geometry on its sphere is studied. The equivalence of the geometry on a sphere of imaginary radius on de Sitter space is shown. The interpretation of the geometry on a sphere of imaginary radius, inside the sphere of imaginary radius of the Minkowski four-dimensional space, is implemented. We study a curve in a five-dimensional pseudo-Euclidean space of index two and determine the membership condition of the curve to a sphere of imaginary radius.


Dirichlet Problem In The Class Of A(Z)-Harmonic Functions, Shohruh Khursanov Dec 2021

Dirichlet Problem In The Class Of A(Z)-Harmonic Functions, Shohruh Khursanov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

This paper work is devoted to the study of the Dirichlet problem in the class of A(z)-harmonic functions.


Electrodeless Electrochemistry Enabled By Nonthermal Plasma, Harold Oldham Dec 2021

Electrodeless Electrochemistry Enabled By Nonthermal Plasma, Harold Oldham

McKelvey School of Engineering Theses & Dissertations

The increasing availability and decreasing cost of electricity generated by renewable resources have motivated research into electrified chemical processing, whereby electrical energy is used to drive chemical transformations. Electricity-intensive processing techniques such as electrochemistry using solid electrodes has attracted attention in this context for the synthesis of organic compounds, such as high-value pharmaceuticals and renewable chemical production. Selective chemical transformations are achieved in conventional aqueous electrochemical systems by using external circuitry to bias solid electrodes, allowing for the preferential transfer of electrons between the electrode-liquid interface. Despite having the ability to promote controlled electrochemical reactions, configurations using solid electrodes are …


Modifying The Aspect Survey To Support The Validity Of Student Perception Data From Different Active Learning Environments, Nicole Naibert, Erin E. Shortlidge, Jack Barbera Dec 2021

Modifying The Aspect Survey To Support The Validity Of Student Perception Data From Different Active Learning Environments, Nicole Naibert, Erin E. Shortlidge, Jack Barbera

Chemistry Faculty Publications and Presentations

Measuring students’ perceptions of active learning activities may provide valuable insight into their engagement and subsequent performance outcomes. A recently published measure, the Assessing Student Engagement in Class Tool (ASPECT), was developed to assess student perceptions of various active learning environments. As such, we sought to use this measure in our courses to assess the students’ perceptions of different active learning environments. Initial results analyzed with confirmatory factor analysis (CFA) indicated that the ASPECT did not function as expected in our active learning environments. Therefore, before administration within an introductory biology course that incorporated two types of active learning strategies, …


Identifying Bots On Twitter With Benford’S Law, Sanmesh Bhosale Dec 2021

Identifying Bots On Twitter With Benford’S Law, Sanmesh Bhosale

Master's Projects

Over time Online Social Networks (OSNs) have grown exponentially in terms of active users and have now become an influential factor in the formation of public opinions. Due to this, the use of bots and botnets for spreading misinformation on OSNs has become a widespread concern. The biggest example of this was during the 2016 American Presidential Elections, where Russian bots on Twitter pumped out fake news to influence the election results.

Identifying bots and botnets on Twitter is not just based on visual analysis and can require complex statistical methods to score a profile based on multiple features and …


On The Study Of Age-Related Physiological Decline In C. Elegans, Drew Benjamin Sinha Dec 2021

On The Study Of Age-Related Physiological Decline In C. Elegans, Drew Benjamin Sinha

McKelvey School of Engineering Theses & Dissertations

Aging decline is a universal and unescapable phenomenon; as organisms reach maturity and continue living, physiological function inevitably declines, resulting in mortality. While the study of mortality has been long studied, technical and practical challenges have limited the equally important study of how/when individuals deteriorate and what types of factors affect that deterioration. This gap in knowledge is not only evident in a relative lack of empirical data on physiological decline, but considerable debate around the analysis and conceptual interpretations of the little data that is available.

In this dissertation, I use quantitative reasoning and analysis of longitudinal data to …


Ultrafast Spectroscopy Of Air Lasing In Filaments, Brian Robert Kamer Dec 2021

Ultrafast Spectroscopy Of Air Lasing In Filaments, Brian Robert Kamer

Optical Science and Engineering ETDs

Filamentation in air is a phenomenon that has been extensively investigated for the last two decades. At sufficiently high intensity, even air is a nonlinear medium. These intensities are reached with ultrashort pulses (50 to 100 fs) of more than 1 J energy, which self-focus in air, reach ionizing intensities of oxygen and nitrogen, creating a plasma that defocuses the beam. The air filament is a self-induced waveguide resulting from a balance of focusing and defocusing. In this work new techniques were developed to visualize and analyze this phenomenon through its emission, in particu- lar the UV emission of the …


Utilizing Software Engineering And Cloud Computing Principles To Develop The Revised Self-Report Assessment Of Functional Visual Performance (R-Srafvp) Application, Kirk Hedlich Dec 2021

Utilizing Software Engineering And Cloud Computing Principles To Develop The Revised Self-Report Assessment Of Functional Visual Performance (R-Srafvp) Application, Kirk Hedlich

Culminating Experience Projects

Can principles from software engineering and concepts from cloud computing be applied to and aid in the development of a small project, specifically improving the use of the Revised Self-Report Assessment of Functional Visual Performance (R-SRAFVP)? The target for this project is to create a new application and improve on existing attempts to move the R-SRAFVP assessment from an electronic document format to a web-based application. The new application should provide better ease of use, simplicity in design and understanding for use, and hopefully increased access and adoption by Occupation Therapists who specialize in low vision rehabilitation. The benefits of …


Limits On Parameter Estimation Of Quantum Channels, Vishal Katariya Dec 2021

Limits On Parameter Estimation Of Quantum Channels, Vishal Katariya

LSU Doctoral Dissertations

The aim of this thesis is to develop a theoretical framework to study parameter estimation of quantum channels. We begin by describing the classical task of parameter estimation that we build upon. In its most basic form, parameter estimation is the task of obtaining an estimate of an unknown parameter from some experimental data. This experimental data can be seen as a number of samples of a parameterized probability distribution. In general, the goal of such a task is to obtain an estimate of the unknown parameter while minimizing its error.

We study the task of estimating unknown parameters which …