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Full-Text Articles in Physical Sciences and Mathematics

The Impact Of Ethical Hacking Within Small Businesses, Nygia Tribbey Oct 2022

The Impact Of Ethical Hacking Within Small Businesses, Nygia Tribbey

Cybersecurity Undergraduate Research Showcase

The Internet has brought about a new way for businesses to reach their customers. With the help of social media, websites, and email marketing, small businesses have gained a lot of new customers. However, these new online customers have also opened up their businesses to a whole new world of cyber crime. Cyber crime is the illegal use of computers and networks to cause damage or steal information. This type of crime affects small businesses as well as large corporations. Small businesses often find themselves at a disadvantage because they don't have the resources to hire an ethical hacker or …


Topological Phase Transitions And Berry-Phase Hysteresis In Exchange-Coupled Nanomagnets, Ahsan Ullah, Xin Li, Yunlong Jin, Rabindra Pahari, Lanping Yue, Xiaoshan S. Xu, Balamurugan Balasubramanian,, David J. Sellmyer, Ralph Skomski Oct 2022

Topological Phase Transitions And Berry-Phase Hysteresis In Exchange-Coupled Nanomagnets, Ahsan Ullah, Xin Li, Yunlong Jin, Rabindra Pahari, Lanping Yue, Xiaoshan S. Xu, Balamurugan Balasubramanian,, David J. Sellmyer, Ralph Skomski

Department of Physics and Astronomy: Faculty Publications

Topological phase in magnetic materials yields a quantized contribution to the Hall effect known as the topological Hall effect, which is often caused by skyrmions, with each skyrmion creating a magnetic flux quantum ±h/e. The control and understanding of topological properties in nanostructured materials is the subject of immense interest for both fundamental science and technological applications, especially in spintronics. In this work, the electron-transport properties and spin structure of exchange-coupled cobalt nanoparticles with an average particle size of 13.7 nm are studied experimentally and theoretically. Magnetic and Hall-effect measurements identify topological phase transitions in the exchange-coupled cobalt …


Mgrre_Thinsections_05_A_60, Mgrre Oct 2022

Mgrre_Thinsections_05_A_60, Mgrre

Thin Sections

No abstract provided.


Electro-Optical Sensors For Atmospheric Turbulence Strength Characterization With Embedded Edge Ai Processing Of Scintillation Patterns, Ernst Polnau, Don L. N. Hettiarachchi, Mikhail A. Vorontsov Oct 2022

Electro-Optical Sensors For Atmospheric Turbulence Strength Characterization With Embedded Edge Ai Processing Of Scintillation Patterns, Ernst Polnau, Don L. N. Hettiarachchi, Mikhail A. Vorontsov

Electro-Optics and Photonics Faculty Publications

This study introduces electro-optical (EO) sensors (TurbNet sensors) that utilize a remote laser beacon (either coherent or incoherent) and an optical receiver with CCD camera and embedded edge AI computer (Jetson Xavier Nx) for in situ evaluation of the path-averaged atmospheric turbulence refractive index structure parameter C-n(2) at a high temporal rate. Evaluation of C-n(2) values was performed using deep neural network (DNN)-based real-time processing of short-exposure laser-beacon light intensity scintillation patterns (images) captured by a TurbNet sensor optical receiver. Several pre-trained DNN models were loaded onto the AI computer and used for TurbNet sensor performance evaluation in a set …


Social Media Time Series Forecasting And User-Level Activity Prediction With Gradient Boosting, Deep Learning, And Data Augmentation, Fred Mubang Oct 2022

Social Media Time Series Forecasting And User-Level Activity Prediction With Gradient Boosting, Deep Learning, And Data Augmentation, Fred Mubang

USF Tampa Graduate Theses and Dissertations

In the overall history of technological innovations, social media has only existed for a brief time, however its influence is undeniable. Researchers have found that it can be used to influence elections, spread health misinformation, and aid with financial pump-and-dump schemes. Keeping all this in mind, it is clear that more research is needed to predict the spread of information on social media in order to combat its malicious use.

To that end, in this dissertation, we explore the use of Machine Learning algorithms to perform time series forecasting and user-level activity prediction in social media. We address the different …


Association Between Use Of Remdesivir And Bradycardia, Gibret Umeukeje Oct 2022

Association Between Use Of Remdesivir And Bradycardia, Gibret Umeukeje

USF Tampa Graduate Theses and Dissertations

Remdesivir received the first emergency use authorization from the FDA for the treatment of COVID-19. Multiple adverse drug reactions (ADR) have been reported since its approval in October 2020. Bradycardia, defined by a decrease in heart rate has been reported as an adverse event for patients receiving remdesivir for COVID-19 treatment. The purpose of the research is to systematically investigate the frequency of occurrence of bradycardia in adults receiving remdesivir using clinical data derived from the FDA Adverse Event Reporting System (FAERS) database. Patients receiving remdesivir were compared to those receiving Paxlovid, Regen-Cov, and Dexamethasone for COVID-19 treatment to see …


Design And Evaluation Of Miniaturized Ion Trap Mass Analyzers Using Simulation, Radhya Weligama Gamage Oct 2022

Design And Evaluation Of Miniaturized Ion Trap Mass Analyzers Using Simulation, Radhya Weligama Gamage

Theses and Dissertations

Mass spectrometry is a technique that analyzes the chemical compositions of compounds based on the mass-to-charge ratio of their ionized constituents. Miniaturized ion trap mass spectrometry finds application in a wide range of fields where portable, rugged, and reliable analytical instruments are required. Ion traps of various designs have been introduced over the past decades, each with their own unique advantages and capabilities. However, the process of developing a novel miniaturized ion trap mass spectrometer continues to be fraught with challenges. This dissertation discusses simulation studies pertaining to the development of a novel dual ion trap, the simplified coaxial ion …


Spectroscopic Properties Of The Astrochemical Molecules [Al, O, Si]X (X = 0, +1), Jacqueline M. Friskey, Vincent J. Esposito, Tarek Trabelsi, Joseph S. Francisco Oct 2022

Spectroscopic Properties Of The Astrochemical Molecules [Al, O, Si]X (X = 0, +1), Jacqueline M. Friskey, Vincent J. Esposito, Tarek Trabelsi, Joseph S. Francisco

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aluminum and silicon are present in large quantities in the interstellar medium, making the triatomic species consisting of both elements intriguing with regard to the foundations of astrochemistry. Spectroscopic parameters have been calculated via high-level ab initio methods to assist with laboratory and observational detection of [Al, O, Si]x(x = 0,+1). All [Al, O, Si]Mx(x = 0,+1) isomers exist in the linear geometry, with linear AlOSi (X 2Π) and linear AlOSi+ (X1Δ) being the most stable neutral and cationic species, respectively. Formation of the neutral species most likely occurs via reaction of …


The Impact Of Covid-19 On Opioid-Related Overdose Deaths In Texas, Bhanumathi Gopal, Tiffany Champagne-Langabeer Oct 2022

The Impact Of Covid-19 On Opioid-Related Overdose Deaths In Texas, Bhanumathi Gopal, Tiffany Champagne-Langabeer

Faculty, Staff and Student Publications

Prior to the COVID-19 pandemic, the United States was facing an epidemic of opioid overdose deaths, clouding accurate inferences about the impact of the pandemic at the population level. We sought to determine the existence of increases in the trends of opioid-related overdose (ORO) deaths in the Greater Houston metropolitan area from January 2015 through December 2021, and to describe the social vulnerability present in the geographic location of these deaths. We merged records from the county medical examiner's office with social vulnerability indexes (SVIs) for the region and present geospatial locations of the aggregated ORO deaths. Time series analyses …


Emotion Quantification Using Variational Quantum State Fidelity Estimation, Jaiteg Singh, Farman Ali, Babar Shah, Kamalpreet Singh Bhangu, Daehan Kwak Oct 2022

Emotion Quantification Using Variational Quantum State Fidelity Estimation, Jaiteg Singh, Farman Ali, Babar Shah, Kamalpreet Singh Bhangu, Daehan Kwak

All Works

Sentiment analysis has been instrumental in developing artificial intelligence when applied to various domains. However, most sentiments and emotions are temporal and often exist in a complex manner. Several emotions can be experienced at the same time. Instead of recognizing only categorical information about emotions, there is a need to understand and quantify the intensity of emotions. The proposed research intends to investigate a quantum-inspired approach for quantifying emotional intensities in runtime. The inspiration comes from manifesting human cognition and decision-making capabilities, which may adopt a brief explanation through quantum theory. Quantum state fidelity was used to characterize states and …


Deep Investigation Of Neutral Gas Origins (Dingo): Hi Stacking Experiments With Early Science Data, Jonghwan Rhee, Richard Dodson, Kristóf Rozgonyi, Sarah Brough, Benne Holwerda, Simon Driver, Attila Popping, Sambit Roychowdhury, Sabine Bellstedt, Michael J. I. Brown, Lister Staveley-Smith, Ivan Baldry, Angel Lopez-Sanchez, Martin Meyer, Elizabeth Mahony, Aaron Robotham, Andrew Hopkins, Karen Lee-Waddell Oct 2022

Deep Investigation Of Neutral Gas Origins (Dingo): Hi Stacking Experiments With Early Science Data, Jonghwan Rhee, Richard Dodson, Kristóf Rozgonyi, Sarah Brough, Benne Holwerda, Simon Driver, Attila Popping, Sambit Roychowdhury, Sabine Bellstedt, Michael J. I. Brown, Lister Staveley-Smith, Ivan Baldry, Angel Lopez-Sanchez, Martin Meyer, Elizabeth Mahony, Aaron Robotham, Andrew Hopkins, Karen Lee-Waddell

Faculty and Staff Scholarship

We present early science results from Deep Investigation of Neutral Gas Origins (DINGO), an H I survey using the Australian Square Kilometre Array Pathfinder (ASKAP). Using ASKAP subarrays available during its commissioning phase, DINGO early science data were taken over ∼60 deg2 of the Galaxy And Mass Assembly (GAMA) 23 h region with 35.5 h integration time. We make direct detections of six known and one new sources at z < 0.01. Using H I spectral stacking, we investigate the H I gas content of galaxies at 0.04 < z < 0.09 for different galaxy colours. The results show that galaxy morphology based on optical colour is strongly linked to H I gas properties. To examine environmental impacts on the H I gas content of galaxies, three subsamples are made based on the GAMA group catalogue. The average H I mass of group central galaxies is larger than those of satellite and isolated galaxies, but with a lower H I gas fraction. We derive a variety of H I scaling relations for physical properties of our sample, including stellar mass, stellar mass surface density, NUV − r colour, specific star formation rate, and halo mass. We find that the derived H I scaling relations are comparable to other published results, with consistent trends also observed to ∼0.5 dex lower limits in stellar mass and stellar surface density. The cosmic H I densities derived from our data are consistent with other published values at similar redshifts. DINGO early science highlights the power of H I spectral stacking techniques with ASKAP


River Discharge Mediates Extent Of Phytoplankton And Harmful Algal Bloom Habitat In The Columbia River Estuary (Usa) During North Pacific Marine Heat Waves, Taylor N. Dodrill, Yangdong Pan, Tawnya D. Peterson Oct 2022

River Discharge Mediates Extent Of Phytoplankton And Harmful Algal Bloom Habitat In The Columbia River Estuary (Usa) During North Pacific Marine Heat Waves, Taylor N. Dodrill, Yangdong Pan, Tawnya D. Peterson

Environmental Science and Management Faculty Publications and Presentations

Marine heat waves (MHWs) have been associated with extensive harmful algal blooms (HABs) in the northeast Pacifc Ocean, but the degree to which these large-scale oceanographic events are mirrored in nearshore environments has not been well established. We compared phytoplankton assemblages in the Lower Columbia River Estuary (LCRE) during two Pacifc MHWs that took place in 2015 and 2019, with observations from 2017, a year with no MHW. These data were paired with environmental data from the summers of 2015–2019 to characterize differences in estuarine conditions during MHWs that promote phytoplankton assemblage transitions and identify HAB-conducive conditions. Bloom densities of …


An Algorithm For Indoor Sars-Cov-2 Transmission, Daniel Maxin, Spencer Gannon Oct 2022

An Algorithm For Indoor Sars-Cov-2 Transmission, Daniel Maxin, Spencer Gannon

Journal of Mind and Medical Sciences

We propose a computer modeling approach for SARS-CoV-2 transmission that can be preferable to a purely mathematical framework. It is illustrated its functionality in a specific case of indoor transmission. Based on literature, we assume that infection is due to aerosols with viral particles that persist and accumulate for hours in the air even after the persons who produced them left the space. We incorporate also restricted opening hours as a mitigation measure and one possible behavioral change in response to this measure. It is shown via several examples how this algorithmic modeling approach can be used to run various …


Evaluating Optical Remote Sensing Methods For Estimating Leaf Area Index For Corn And Soybean, Rohit Nandan, Varaprasad Bandaru, Jiaying He, Craig Daughtry, Prasanna Gowda, Andrew E. Suyker Oct 2022

Evaluating Optical Remote Sensing Methods For Estimating Leaf Area Index For Corn And Soybean, Rohit Nandan, Varaprasad Bandaru, Jiaying He, Craig Daughtry, Prasanna Gowda, Andrew E. Suyker

School of Natural Resources: Faculty Publications

The leaf area index (LAI) is a key crop biophysical variable influencing many vegetation processes. Spatial LAI estimates are essential to develop and improve spatial modeling tools to monitor vegetation conditions at large regional scales. Numerous optical remote sensing methods have been explored to retrieve crop-specific LAI at a regional scale using satellite observations. However, a major challenge is selecting a method that performance well under various conditions without local scale calibration. As such, we assessed the performance of existing statistical and physical approaches, developed based on parametric, non-parametric and radiative transfer model (RTM)-look-up-table based inversion, using field observations from …


Mgrre_Thinsections_05_A_59, Mgrre Oct 2022

Mgrre_Thinsections_05_A_59, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_05_A_58, Mgrre Oct 2022

Mgrre_Thinsections_05_A_58, Mgrre

Thin Sections

No abstract provided.


Seasonal Controls On Nearshore Dissolved Oxygen Variability And Hypoxia In A Coastal Embayment, Ryan K. Walter, Stephen A. Huie, Jon Christian P. Abraham, Alexis Pasulka, Kristen A. Davis, Thomas P. Connolly, Piero L.F. Mazzini, Ian Robbins Oct 2022

Seasonal Controls On Nearshore Dissolved Oxygen Variability And Hypoxia In A Coastal Embayment, Ryan K. Walter, Stephen A. Huie, Jon Christian P. Abraham, Alexis Pasulka, Kristen A. Davis, Thomas P. Connolly, Piero L.F. Mazzini, Ian Robbins

Physics

Declining dissolved oxygen (DO) is emerging as an increasingly important stressor in nearshore ecosystems, and there is a growing need to better understand DO dynamics and hypoxia risk in this highly variable environment. In this study, we collected data from monthly cruises on the inner shelf, continuous nearshore moorings inside and outside a small coastal upwelling embayment (San Luis Obispo Bay in Central California), and weekly phytoplankton measurements inside the bay during the upwelling season. Nearshore DO was generally dominated by low-frequency synoptic variability, with increased DO variance near the surface relative to the bottom and inside the bay compared …


Algorithmic Rationality, Rohit J. Parikh Oct 2022

Algorithmic Rationality, Rohit J. Parikh

Publications and Research

The notion of rationality is much discussed by both Economists and Philosophers. Perhaps you are rational if you accept certain axioms of rationality. If you prefer A to B and B to C then you must prefer A to C. Or you can define rationality in terms of the net results of your behavior. We examine a notion of algorithmic rationality. Even animals upwards from the humble tick carry out algorithms. Are they rational? And can we use this theory to define the IQ of animals?


Preparation, Investigation, And Temperature Sensing Application Of Rgo/Sno2/Co3o4 Composite, Mohamed Morsy Oct 2022

Preparation, Investigation, And Temperature Sensing Application Of Rgo/Sno2/Co3o4 Composite, Mohamed Morsy

Nanotechnology Research Centre

No abstract provided.


P-39 Interdisciplinary Diffusion Lab, Sable Canales, Chloe Gaban, Mickey Kutzner Oct 2022

P-39 Interdisciplinary Diffusion Lab, Sable Canales, Chloe Gaban, Mickey Kutzner

Celebration of Research and Creative Scholarship

Diffusion is a principle in Physics, Chemistry, and Biology. The rate of diffusion is affected by temperature, particle size, concentration, and material type. Students can model the rate of diffusion based on particle size by contrasting blue and yellow dyes. Two petri dishes containing agar-agar receive a drop of dye at the center. The radius of expansion is recorded over time. The variance of the distribution grows as ��2=4����, where ��2 is the variance, D is the diffusion constant, and t is time. Graphing variance versus time gives a slope of 4D. Diffusion constants vary by particle size, allowing for …


P-37 Self And Mixed Delta Moves On Algebraically Split Links, Justyce Goode, Davielle Smith, Yamil Kas-Danouche, Devin Garcia, Anthony Bosman Oct 2022

P-37 Self And Mixed Delta Moves On Algebraically Split Links, Justyce Goode, Davielle Smith, Yamil Kas-Danouche, Devin Garcia, Anthony Bosman

Celebration of Research and Creative Scholarship

A link is an embedding of circles into 3-dimensional space. A Delta-move is a local move on a link diagram. The Delta-Gordian distance between links measures the minimum number of Delta-moves needed to move between link diagrams. We place restrictions on the Delta-move by either requiring the move to only involve a single component of the link, called a self Delta-move, or multiple components of the link, called a mixed Delta-move. We prove a number of results on how (mixed/self) Delta-moves relate to classical link invariants including the Arf invariant and crossing number. This allows us to produce a graph …


P-36 The Delta-Crossing Number For Links, Zachary Duah Oct 2022

P-36 The Delta-Crossing Number For Links, Zachary Duah

Celebration of Research and Creative Scholarship

An m-component link is an embedding of m circles into 3-dimensional space; a 1-component link is called a knot. The diagram for a link may be drawn so that all crossings occur within delta tangles, collections of three crossings as appear in a delta move. The delta crossing number is defined to be the minimal number of delta tangles in such a diagram. The delta crossing number has been well-studied for knots but not for links with multiple components. Using bounds we determine the delta crossing number for several 2-component links with up to 8 crossings as well as for …


Accuracies Of Field Co2–H2O Data From Open-Path Eddy-Covariance Flux Systems: Assessment Based On Atmospheric Physics And Biological Environment, Xinhua Zhou, Tian Gao, Ning Zheng, Bai Yang, Yanlei Li, Fengyuan Yu, Tala Awada, Jiaojun Zhu Oct 2022

Accuracies Of Field Co2–H2O Data From Open-Path Eddy-Covariance Flux Systems: Assessment Based On Atmospheric Physics And Biological Environment, Xinhua Zhou, Tian Gao, Ning Zheng, Bai Yang, Yanlei Li, Fengyuan Yu, Tala Awada, Jiaojun Zhu

School of Natural Resources: Faculty Publications

Ecosystem CO2–H2O data measured by infrared gas analyzers in open-path eddy-covariance (OPEC) systems have numerous applications, such as estimations of CO2 and H2O fluxes in the atmospheric boundary layer. To assess the applicability of the data for these estimations, data uncertainties from analyzer measurements are needed. The uncertainties are sourced from the analyzers in zero drift, gain drift, cross-sensitivity, and precision variability. These four uncertainty sources are individually specified for analyzer performance, but so far no methodology exists yet to combine these individual sources into a composite uncertainty for the specification of an …


Mgrre_Thinsections_10-A_3, Mgrre Oct 2022

Mgrre_Thinsections_10-A_3, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_10-A_4, Mgrre Oct 2022

Mgrre_Thinsections_10-A_4, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_10-A_12, Mgrre Oct 2022

Mgrre_Thinsections_10-A_12, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_10-A_34, Mgrre Oct 2022

Mgrre_Thinsections_10-A_34, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_10-A_51, Mgrre Oct 2022

Mgrre_Thinsections_10-A_51, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_11-A_6, Mgrre Oct 2022

Mgrre_Thinsections_11-A_6, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_11-A_14, Mgrre Oct 2022

Mgrre_Thinsections_11-A_14, Mgrre

Thin Sections

No abstract provided.