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Articles 36301 - 36330 of 302422

Full-Text Articles in Physical Sciences and Mathematics

Applications For Machine Learning On Readily Available Data From Virtual Reality Training Experiences, Alec Moore Jan 2022

Applications For Machine Learning On Readily Available Data From Virtual Reality Training Experiences, Alec Moore

Electronic Theses and Dissertations, 2020-2023

The purpose of the research presented in this dissertation is to improve virtual reality (VR) training systems by enhancing their understanding of users. While the field of intelligent tutoring systems (ITS) has seen value in this approach, much research into making use of biometrics to improve user understanding and subsequently training, relies on specialized hardware. Through the presented research, I show that with machine learning (ML), the VR system itself can serve as that specialized hardware for VR training systems. I begin by discussing my explorations into using an ecologically valid, specialized training simulation as a testbed to predict knowledge …


Characterizing The Effects Of Porosity And Particle Size On Tir Emissivity Spectral Features Of Olivine, Ryan Galinkin Jan 2022

Characterizing The Effects Of Porosity And Particle Size On Tir Emissivity Spectral Features Of Olivine, Ryan Galinkin

Electronic Theses and Dissertations, 2020-2023

We generated a series of 15 particulate San Carlos olivine samples with varying porosity and particle size. We created five different particle size distributions and each particle size distribution was prepared with three different packing techniques. These samples were then imaged under a microscope and a binarization thresholding technique was used to determine each sample's surface porosity by the ratio of dark, void pixels to the total number of pixels in each image. Our results show that we could estimate surface porosity from the analysis of a microscopic image, a non-destructive technique. These samples were then placed in the Planetary …


Addressing Human-Centered Artificial Intelligence: Fair Data Generation And Classification And Analyzing Algorithmic Curation In Social Media, Amirarsalan Rajabi Jan 2022

Addressing Human-Centered Artificial Intelligence: Fair Data Generation And Classification And Analyzing Algorithmic Curation In Social Media, Amirarsalan Rajabi

Electronic Theses and Dissertations, 2020-2023

With the growing impact of artificial intelligence, the topic of fairness in AI has received increasing attention. Artificial intelligence is observed to have caused unanticipated negative consequences. In this dissertation, we address two critical aspects regarding human-centered artificial intelligence (HCAI), a new paradigm for developing artificial intelligence that is ethical, fair, and helps to improve the human condition. In the first part of this dissertation, we investigate the effect that AI curation of contents by social media platforms has on an online discussions, by studying a polarized discussion in the Twitter network. We then develop a network communication model that …


Authoring Tools For Augmented Reality Scenario Based Training Experiences, Andres Vargas Gonzalez Jan 2022

Authoring Tools For Augmented Reality Scenario Based Training Experiences, Andres Vargas Gonzalez

Electronic Theses and Dissertations, 2020-2023

Augmented Reality's (AR) scope and capabilities have grown considerably in the last few years. AR applications can be run across devices such as phones, wearables, and head-mounted displays (HMDs). The increasing research and commercial efforts in HMDs capabilities allow end users to map a 3D environment and interact with virtual objects that can respond to the physical aspects of the scene. Within this context, AR is an ideal format for in-situ training scenarios. However, building such AR scenarios requires proficiency in game engine development environments and programming expertise. These difficulties can make it challenging for domain experts to create training …


Compact Lens Technologies: Curved Image Sensor And Volumetric Imaging Efficiency, Zhao Ma Jan 2022

Compact Lens Technologies: Curved Image Sensor And Volumetric Imaging Efficiency, Zhao Ma

Electronic Theses and Dissertations, 2020-2023

Compact image systems bring up people's attention in the field of target recognition, surveillance, situation awareness or even photography. Conventional metrics assess image system based on image quality without considering systems' volume. More comprehensive metrics, such as General Image-Quality Equation and the Targeting Task Performance metric, incorporates all image system components from object, lenses to detector and even imaging processing algorithm. All these key factors prohibit these metrics from being applied to image system in a convenient manner. Here, we propose a simple metric, volumetric imaging efficiency, considering both image quality and volume. Only concentrate on optical lenses enables the …


Analysis Of Blue Fountain Pen Ink By Uv-Vis Spectroscopy, Atr-Ftir Spectroscopy, And Thin Layer Chromatography Enhanced With Rgb Spot Evaluation To Construct A Database For Comparison And Identification., Elliot D. Quinteros Jan 2022

Analysis Of Blue Fountain Pen Ink By Uv-Vis Spectroscopy, Atr-Ftir Spectroscopy, And Thin Layer Chromatography Enhanced With Rgb Spot Evaluation To Construct A Database For Comparison And Identification., Elliot D. Quinteros

Dissertations and Theses

Pen ink can be a crucial piece of physical evidence in the area of Forensic Science. For example, evidence such as notes, letters, printed documents, checks, currency, ransom notes, and books may contain ink. Analysis of ink is typically done for identification or differentiation purposes. To improve existing methods, it was proposed to create a database with many samples and experimental information. The methods used and evaluated were thin-layer chromatography (TLC) enhanced with RGB spot evaluation, UV-Vis spectroscopy, and ATR-FTIR spectroscopy. All three methods were used to analyze 89 fountain pen ink samples. All three methods were able to discriminate …


Sea Surface Temperatures And Vertical Wind Shear As Precursors To Tropical Cyclone Activity In The Caribbean And An Expanding Main Developing Region, Keneshia Hibbert Jan 2022

Sea Surface Temperatures And Vertical Wind Shear As Precursors To Tropical Cyclone Activity In The Caribbean And An Expanding Main Developing Region, Keneshia Hibbert

Dissertations and Theses

Sea surface temperatures and vertical wind shear are essential to tropical cyclone formation. TCs need warm SSTs and low shear for genesis. Increasing SSTs and VWS changes influence storm development. This work analyzes SST and VWS trends for the Caribbean, surrounding region, and the Atlantic hurricane main developing region from 1982 to 2020. Storm intensity increases significantly during this period. Annual and seasonal trends show regional SSTs in the MDR are warming annually (0.0219°C yr-1) and per season (0.0280°C yr-1). Simultaneously, VWS decreases during the late rainfall season at 0.0556m/s yr-1 in the MDR and …


Electron Deficient Fluoroarenes: Bridging Deoxyfluorination And Anion-Π Interactions To Produce New Fluorination Reagents, Jordan Houston Kramer Jan 2022

Electron Deficient Fluoroarenes: Bridging Deoxyfluorination And Anion-Π Interactions To Produce New Fluorination Reagents, Jordan Houston Kramer

Dissertations and Theses

Fluorination is a ubiquitous in modern materials and pharmaceuticals due to organofluorine compounds possessing unique physicochemical properties. However, this process is a demanding task due to difficulty in handling key reagents for selective fluorination. One strategy is the usage of deoxyfluorination reagents due to the wide availability of oxygen in many functional moieties. These reagents have allowed to production of new fluorinated materials and pharmaceuticals, yet the costs of several reagents and instabilities for others lead to restricted conditions, functional group tolerance, and safety risks for both users and the environment. Reported here is the culmination of a new hypothesis …


Measuring The Social And Ecological Performance Of Agricultural Innovations On Rangelands: Progress And Plans For An Indicator Framework In The Ltar Network, S. Spiegal, N. P. Webb, E. H. Boughton, R. K. Boughton, A. Bentley Brymer, P. E. Clark, C. D. Holifield Collins, D. L. Hoover Et. Al Jan 2022

Measuring The Social And Ecological Performance Of Agricultural Innovations On Rangelands: Progress And Plans For An Indicator Framework In The Ltar Network, S. Spiegal, N. P. Webb, E. H. Boughton, R. K. Boughton, A. Bentley Brymer, P. E. Clark, C. D. Holifield Collins, D. L. Hoover Et. Al

School of Natural Resources: Faculty Publications

No abstract provided.


The Parker Problem In Hall Magnetohydrodynamics Analytical And Numerical Solutions, Chad Malott Jan 2022

The Parker Problem In Hall Magnetohydrodynamics Analytical And Numerical Solutions, Chad Malott

Electronic Theses and Dissertations, 2020-2023

In this thesis we follow on the mathematical aspects of the previous work of Shivamoggi (2009) on the Parker problem in Hall magnetohydrodynamics (MHD). We will present an analysis involving detailed analytical and numerical solutions to the Parker problem in Hall MHD. We give an analytical formulation for the Parker problem in Hall MHD, involving an initial value problem (IVP) associated with a first order Riccati equation (RE). We present Mathematica software exact solutions directly with special functions and more straightforward solutions that use the change of variables and power series methods without special functions. We give an asymptotic formulation …


Quantum Graph Parameters, Parisa Darbari Kozekanan Jan 2022

Quantum Graph Parameters, Parisa Darbari Kozekanan

Electronic Theses and Dissertations, 2020-2023

This dissertation considers some of the advantages, and limits, of applying quantum computing to solve two important graph problems. The first is estimating a graph's quantum chromatic number. The quantum chromatic number is the minimum number of colors necessary in a two-player game where the players cannot communicate but share an entangled state and must convince a referee with probability one that they have a proper vertex coloring. We establish several spectral lower bounds for the quantum chromatic number. These lower bounds extend the well-known Hoffman lower bound for the classical chromatic number. The second is the Pattern Matching on …


Controls On Carbon Gas Fluxes From A Temperate Forest Soil, Natalie A. White, Ruth K. Varner, Clarice R. Perryman Jan 2022

Controls On Carbon Gas Fluxes From A Temperate Forest Soil, Natalie A. White, Ruth K. Varner, Clarice R. Perryman

Honors Theses and Capstones

Forest soils consume atmospheric methane (CH4), serving as a major global CH4 sink that uptake an estimated 22 ± 12 Tg of CH4 per year. Temperature and soil moisture have been identified as key controls of the microbial consumption of CH4 in forest soils. Climate-driven warming and changing moisture regimes may impact forest soils’ role in the carbon cycle, and recent works suggests that forests could become weaker CH₄ sinks. Long-term monitoring sites can capture these changes, leading to better predictions of CH4 exchange between the atmosphere and soils under climate change. This study …


Robot Guided Exercise Training: The Role Of The Human Model, Selena R. Richards Jan 2022

Robot Guided Exercise Training: The Role Of The Human Model, Selena R. Richards

Honors Theses and Capstones

Physical therapy after an injury can be difficult for patients to access, whether it be due to location, finances, or other factors. To make physical therapy more accessible, robot-guided exercise training can be used. Commercial anthropomorphic robots have been created and have human-like movement, but may still lack qualities that make it easy for a human to understand its intentions intuitively. A human model that mimics the movement of a robot performing human exercises can be used to complement the robot and increase human understanding. The ideal model would be viewable from different angles and could visibly show the difference …


Impact Of Drought Stress On Oak Stomatal Size And Density At Thompson Farm, Nh, Emily Chen Jan 2022

Impact Of Drought Stress On Oak Stomatal Size And Density At Thompson Farm, Nh, Emily Chen

Honors Theses and Capstones

Global climate change is likely to affect northeastern U.S. forests by increasing the frequency and severity of drought events. Historically, droughts rarely occurred in this region, so native tree species are not well-adapted to extreme moisture stress. In the future, the changing climate will likely cause unprecedented levels of low water availability which may have implications on future forest composition. It is hypothesized that trees can respond to these environmental changes by altering their functional traits, also referred to as phenotypic plasticity; for example, by producing leaves with fewer and smaller stomata.

To determine the capacity to which oak trees …


Attempts To Measure Nanosecond Resolved Electronic Dynamics Of Charge Density Wave Phase Transition In 1t-Tas2, Ben Campbell Jan 2022

Attempts To Measure Nanosecond Resolved Electronic Dynamics Of Charge Density Wave Phase Transition In 1t-Tas2, Ben Campbell

Honors Theses and Capstones

Scanning tunneling microscopes allow for atomic spatial resolution but the resulting images are necessarily time-averaged and fast dynamics are lost. Pump-probe spectroscopy is a common optical technique used to measure ultrafast electronic dynamics but the integration of optical pump-probe spectroscopy into an STM requires specialized knowledge and equipment. Alternatively, an all-electronic pump-probe spectroscopy technique has recently been developed for use with an STM that replaces the laser pulses of optical pump-probe with voltage pulses. In this paper, I implemented an all-electronic pump-probe scheme into an existing scanning tunneling microscope using an arbitrary waveform generator and a lock-in amplifier. I developed …


The State Of Innovation And Media Viability In East Africa: From Indepth Media House Surveys, Hesbon Hansen Owilla, Rose Kimani, Ann Hollifield, Julia Wegner, Dennis Reineck, Roland Schürhoff Jan 2022

The State Of Innovation And Media Viability In East Africa: From Indepth Media House Surveys, Hesbon Hansen Owilla, Rose Kimani, Ann Hollifield, Julia Wegner, Dennis Reineck, Roland Schürhoff

Graduate School of Media and Communications

Media houses globally are grappling with how best to produce quality content while at the same time remaining financially viable in the wake of shrinking revenues, technological disruptions, the emergence of peripheral content creators, competition for advertisement revenues from big tech platforms, the COVID-19 pandemic, and a myriad of other changes in the ecosystem. Despite these challenges, it is in the interest of the public that news media organisations (NMOs) produce quality content and do so in a financially sustainable fashion. Media viability, that is, producing quality journalism in a financially sustainable way, is, therefore, a growing area of focus. …


Challenges Of Constructing Entrainment Map For Arbitrary Circadian Models, Yuxuan (Nelson) Wu Jan 2022

Challenges Of Constructing Entrainment Map For Arbitrary Circadian Models, Yuxuan (Nelson) Wu

Honors Theses

The entrainment map, developed by Dr.Diekman and Dr.Bose, is claimed to be a 1-dimensional map that produces a better prediction for phase-locking than methods than the phase response curve for circadian models. In his paper, he constructs the entrainment map for the two-dimensional circadian model, the Novak-Tyson model, and the other two higher-dimensional circadian models. For this thesis, we concentrate on exploring if it is viable to construct the entrainment map for other circadian models that are not included in his paper: the Becker-Weimann model and the Relogio model. In addition, we discuss the challenges of constructing the entrainment map …


Apparatus Improvement And Characterisation For Experiments On Ultra-Cold Plasmas., Jakub Bystrický Jan 2022

Apparatus Improvement And Characterisation For Experiments On Ultra-Cold Plasmas., Jakub Bystrický

Honors Theses

Apparatus for creating ultra-cold neutral plasmas (UNPs) was improved and data on plasma expansion was collected. We increase the trapping efficiency of a quadrupole magneto-optical trap (MOT) by installing a tapered amplifier to increase the power of the cooling laser used to trap atoms. We achieve an improvement in density of trapped atoms from 1 x 1010 cm-3 to 2.5 - 4.5 x 1010 cm-3. In addition, to improve precision and decrease systematic error, the magnetic field induced by inductive current in the MOT's anti-helmholtz coils was suppressed. This was achieved by installing a KEPCO …


Decoding Cyclic Codes Via Gröbner Bases, Eduardo Sosa Jan 2022

Decoding Cyclic Codes Via Gröbner Bases, Eduardo Sosa

Honors Theses

In this paper, we analyze the decoding of cyclic codes. First, we introduce linear and cyclic codes, standard decoding processes, and some standard theorems in coding theory. Then, we will introduce Gr¨obner Bases, and describe their connection to the decoding of cyclic codes. Finally, we go in-depth into how we decode cyclic codes using the key equation, and how a breakthrough by A. Brinton Cooper on decoding BCH codes using Gr¨obner Bases gave rise to the search for a polynomial-time algorithm that could someday decode any cyclic code. We discuss the different approaches taken toward developing such an algorithm and …


"It's Not About The Polar Bears": Evangelical Christian Arguments For Environmentalism, Teresa D. White Jan 2022

"It's Not About The Polar Bears": Evangelical Christian Arguments For Environmentalism, Teresa D. White

Honors Theses

In recent history, white conservative evangelical Christians have formed an influential voting bloc of the Republican party in United States politics. Historically, conservatives have often denied the reality of human-induced climate change and have opposed climate change action and many environmental regulations. However, a number of conservative evangelical Christians have split from their traditionally conservative political views and have accepted the reality of climate change, becoming strong advocates for climate change action. This paper examines the arguments often presented by such advocates. I argue that evangelical environmental advocates craft specific arguments to convince fellow evangelicals to care for the environment …


Nft Sneaker Marketplace Design, Testing, And Challenges, Chris Zhu Jan 2022

Nft Sneaker Marketplace Design, Testing, And Challenges, Chris Zhu

Honors Theses

This paper introduces the preliminary background and implementation of the NFT sneaker marketplace. Specifically, we build sneaker NFTs on top of ERC-20 within the Ethereum network and use a top-to-bottom design mechanism. Our website performs well in its functionality, compatibility, and performance. We discuss possible future steps for security implementation. In particular, we recommend using a cold wallet for clients' transactions and implementing multi-signature contracts to avoid spoofing and repudiation. Introducing the sneaker NFT marketplace will vastly reduce the costs of transactions and delivery time in the physical sneaker marketplace. We hope investors in the physical asset space can find …


Analyzing The Free Energy Of Ions Sampling A Voltage Gated Sodium Ion Channel, Isabel Varghese Jan 2022

Analyzing The Free Energy Of Ions Sampling A Voltage Gated Sodium Ion Channel, Isabel Varghese

Honors Theses

Voltage gated sodium ion channels are implicated in cardiac diseases, seizures, etc., and they play a role in maintaining ionic homeostasis in cells. Computational studies use prokaryotic model because they are simpler but function similarly to human voltage gated sodium ion channels. This study uses molecular dynamics (MD) to study three specific questions regarding voltage gated sodium ion channels of Magnetococcus marinus. The first question in this study is how the free energy of sodium diffusion compares to that of calcium ion diffusion. We were not able to find any physically significant information due to poor sampling and a lack …


Highlights Generation For Tennis Matches Using Computer Vision, Natural Language Processing And Audio Analysis, Alon Liberman Jan 2022

Highlights Generation For Tennis Matches Using Computer Vision, Natural Language Processing And Audio Analysis, Alon Liberman

Senior Independent Study Theses

This project uses computer vision, natural language processing and audio analysis to automatize the highlights generation task for tennis matches. Computer vision techniques such as camera shot detection, hough transform and neural networks are used to extract the time intervals of the points. To detect the best points, three approaches are used. Point length suggests which points correspond to rallies and aces. The audio waves are analyzed to search for the highest audio peaks, which indicate the moments where the crowd cheers the most. Sentiment analysis, a natural language processing technique, is used to look for points where the commentators …


Gaia Contributions To Agroecology By James Lovelock (1919-2022), Steve Gliessman, Charles A. Francis Jan 2022

Gaia Contributions To Agroecology By James Lovelock (1919-2022), Steve Gliessman, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

In writing about the history of agroecology we too often ignore the valuable contributions of British scientist James Lovelock who recently died on his 103rd birthday. A prolific inventor and influential theorist, Lovelock is best known for the Gaia hypothesis first proposed during his innovative work in the 1960s with the United States National Aeronautics and Space Administration. He suggested that ‘the biosphere has a regulatory effect on the Earth’s environment that acts to sustain life’ as written in Gaia: A New Look at Life on Earth (Lovelock 1979). Lovelock further proposed that humans have strongly impacted the planet’s capacity …


Periodic Trends In The Infrared And Optical Absorption Spectra Of Metal Chalcogenide Clusters, Alain Ward Jan 2022

Periodic Trends In The Infrared And Optical Absorption Spectra Of Metal Chalcogenide Clusters, Alain Ward

Theses and Dissertations

We have investigated the Optical absorption, Infrared spectra, Binding Energies, and various other cluster properties to determine the existence of periodic trend for Transition Metal Chalcogenide Clusters ligated with CO ligands. We were motivated to answer the question of whether periodic behavior can be observed in properties of octahedral metal-chalcogenide clusters. We have used the Amsterdam Density Functional code to calculate the electronic structure of Transition Metal Chalcogenide Clusters using gradient-corrected density functional theory. We determined the existence of several periodic trends in properties of octahedral Transition Metal Chalcogenide Clusters TM6Se8(CO)6. To investigate these …


Direction Modulated Brachytherapy For The Treatment Of Cervical Cancer, Dylan Richeson Jan 2022

Direction Modulated Brachytherapy For The Treatment Of Cervical Cancer, Dylan Richeson

Theses and Dissertations

Purpose: To evaluate and compare the performance of 9 experimental DMBT tandem models of varying physical dimensions in relation to 24 previously planned HDR cervical cancer treatment plans from multiple institutions that used conventional tandem and rings or ovoid applicators.

Methods and Materials: The DMBT tandem is designed to be used concurrently with IGABT and is made from an MRI-compatible tungsten-alloy rod with 6 channels grooved out of its periphery. 9 experimental DMBT tandem prototypes were provided. Each of the models was of equal lengths but varied in thickness, channel diameter size, and circle channel diameter size. Replanning …


Incorporating Ontological Information In Biomedical Entity Linking Of Phrases In Clinical Text, Evan French Jan 2022

Incorporating Ontological Information In Biomedical Entity Linking Of Phrases In Clinical Text, Evan French

Theses and Dissertations

Biomedical Entity Linking (BEL) is the task of mapping spans of text within biomedical documents to normalized, unique identifiers within an ontology. Translational application of BEL on clinical notes has enormous potential for augmenting discretely captured data in electronic health records, but the existing paradigm for evaluating BEL systems developed in academia is not well aligned with real-world use cases. In this work, we demonstrate a proof of concept for incorporating ontological similarity into the training and evaluation of BEL systems to begin to rectify this misalignment. This thesis has two primary components: 1) a comprehensive literature review and 2) …


Smart City Management Using Machine Learning Techniques, Mostafa Zaman Jan 2022

Smart City Management Using Machine Learning Techniques, Mostafa Zaman

Theses and Dissertations

In response to the growing urban population, "smart cities" are designed to improve people's quality of life by implementing cutting-edge technologies. The concept of a "smart city" refers to an effort to enhance a city's residents' economic and environmental well-being via implementing a centralized management system. With the use of sensors and actuators, smart cities can collect massive amounts of data, which can improve people's quality of life and design cities' services. Although smart cities contain vast amounts of data, only a percentage is used due to the noise and variety of the data sources. Information and communication technology (ICT) …


Role Of Inhibition And Spiking Variability In Ortho- And Retronasal Olfactory Processing, Michelle F. Craft Jan 2022

Role Of Inhibition And Spiking Variability In Ortho- And Retronasal Olfactory Processing, Michelle F. Craft

Theses and Dissertations

Odor perception is the impetus for important animal behaviors, most pertinently for feeding, but also for mating and communication. There are two predominate modes of odor processing: odors pass through the front of nose (ortho) while inhaling and sniffing, or through the rear (retro) during exhalation and while eating and drinking. Despite the importance of olfaction for an animal’s well-being and specifically that ortho and retro naturally occur, it is unknown whether the modality (ortho versus retro) is transmitted to cortical brain regions, which could significantly instruct how odors are processed. Prior imaging studies show different …


Angular Distribution Of Electron-Helium Scattering In The Presence Of A 1.17 Ev Laser Field, Brian N. Kim Jan 2022

Angular Distribution Of Electron-Helium Scattering In The Presence Of A 1.17 Ev Laser Field, Brian N. Kim

Theses and Dissertations--Physics and Astronomy

We have measured relative differential cross sections for 350 eV electrons scattered by a helium target in the presence of 1.17 eV photons from an Nd:YAG laser. We report an angular distribution of free-free electrons that were scattered elastically at angles between 15o and 80o and of free-free electrons that underwent the process of electron-impact excitation of helium to its unresolved (1s2s)1S and (1s2p)1P excited states at angles between 1o and 80o. Our experiments test the momentum transfer dependence and the relationship between elastic and inelastic scattering in the Kroll-Watson approximation. …