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Full-Text Articles in Physical Sciences and Mathematics

Sustainable Development In Hazard Mitigation Planning, Brooke Morrell Apr 2023

Sustainable Development In Hazard Mitigation Planning, Brooke Morrell

Goal 11: Sustainable Cities and Communities

No abstract provided.


Survival Models With Background Mortality, Shujie Chen Apr 2023

Survival Models With Background Mortality, Shujie Chen

Theses and Dissertations

In this dissertation, we focus on studying three mixture cure models with background mortality. With the development of treatment, patients may be cured and suffer from other cause of death. The cure model with background mortality can measure the population cure which refers to the patients with comparable mortality with their counterpart in general population. Three types of survival models are investigated, including generalized odds rate (GOR) model, cure model with background mortality for right censoring and interval censoring, and extended illness death model via incorporating “cure” fraction. All methods are validated via comprehensive simulation studies and real data application. …


Reactive End Capped Polybenzimidazole Oligomers For High Temperature Thermosets And Improved Membranes For Electrochemical Devices, Caroline Marie Rohlfing Apr 2023

Reactive End Capped Polybenzimidazole Oligomers For High Temperature Thermosets And Improved Membranes For Electrochemical Devices, Caroline Marie Rohlfing

Theses and Dissertations

Polybenzimidazoles (PBI) are heterocyclic polymers that possess high thermal and oxidative stability. The inherent strength and chemical and thermal stability of PBI make it ideal for use in extreme environments; however, the current processing of PBI molded parts makes the process practically and economically unfavorable. These intrinsic properties make PBIs of particular interest for many industrial applications, varying from fabrics to membrane materials to molded parts. Processing these molded parts is extremely difficult, as the high glass transition temperature and extremely high melting point (>500°C) of PBI result in poor flow properties of PBI resins even at high temperatures. …


Extreme Covering Systems, Primes Plus Squarefrees, And Lattice Points Close To A Helix, Jack Robert Dalton Apr 2023

Extreme Covering Systems, Primes Plus Squarefrees, And Lattice Points Close To A Helix, Jack Robert Dalton

Theses and Dissertations

This dissertation considers three different topics.

In the first part, we prove that if the least modulus of a distinct covering system is 4, its largest modulus is at least 60; also, if the least modulus is 3, the least common multiple of the moduli is at least 120; finally, if the least modulus is 4, the least common multiple of the moduli is at least 360. The constants 60, 120, and 360 are best possible, they cannot be replaced by larger constants. We also show that there do not exist distinct covering systems with all of the moduli in …


Advancements In Parametric Modal Regression, Qingyang Liu Apr 2023

Advancements In Parametric Modal Regression, Qingyang Liu

Theses and Dissertations

This dissertation considers statistical inference methods for parametric modal regression models. In Chapter 1, we motivate the mode as the measure of central tendency instead of the median or the mean with an example. Following the motivational example, we include an overview of existing modal regression models. Later, in the same chapter, we explain advantages of the parametric modal regression models over existing nonparametric modal regression models. In Chapter 2, we address issues in statistical inference brought in by data contaminated with measurement error. With measurement error in covariates, statistical inference methods designed for modal regression models with error-free covariates …


Utilizing Deep Learning Methods In The Identification And Synthesis Of Gene Regulations, Jiandong Wang Apr 2023

Utilizing Deep Learning Methods In The Identification And Synthesis Of Gene Regulations, Jiandong Wang

Theses and Dissertations

Gene expression is the fundamental differentiation and development process of life. Although all cells in an organism have essentially the same DNA, cell types and activities vary due to changes in gene expression. Gene expression can be influenced by many gene regulations. RNA editing contributes to the variety of RNA and proteins by allowing single nucleotide substitution. Reverse transcription can alter the expression status of genes by inducing genetic diversity and polymorphism via novel insertions, deletions, and recombination events. Gene regulation is critical to normal development because it enables cells to respond rapidly to environmental changes. However, identifying gene regulations …


Evaluation Of A Radium-Thorium Disequilibrium Sediment Method Used To Model And Assess Porewater And Submarine Groundwater Exchange In The Coastal Marsh, Madeline R. Bodine Apr 2023

Evaluation Of A Radium-Thorium Disequilibrium Sediment Method Used To Model And Assess Porewater And Submarine Groundwater Exchange In The Coastal Marsh, Madeline R. Bodine

Theses and Dissertations

Ground, pore, and surface water exchange has been extensively studied in beach and near shore environments but has been long neglected in saltmarsh systems due to their complexity. Saltmarsh systems are of particular importance as they are the interface between fresh and saltwater. Saltmarshes impact carbon exchange, release and sequestration, and they process particulate matter. Understanding the characteristics of a marsh system such as the nutrient and particulate loads in conjunction with the flux of water exchange through the marsh provides a deeper understanding of these systems and can impact our understanding of the global water and carbon cycles, as …


Semantics-Based Data Security Models, Theppatorn Rhujittawiwat Apr 2023

Semantics-Based Data Security Models, Theppatorn Rhujittawiwat

Theses and Dissertations

In this dissertation, we studied how an adversary could attack databases and how the system could prevent or recover from such an attack. Our motivation to improve the current security capabilities of database management systems. We provided better recovery capabilities of database management systems by incorporating data provenance. We also expand our study to express security and privacy needs of data in the Internet of Things (IoT) environments such as a smart home environment. For this, we proposed a stream data security model to theoretically represent the data in the IoT network. We built a dynamic authorization model on our …


Hydrothermal Liquefaction Of Saccharina Latissima For The Production Of Biofuel, Mayokun A. Oke Apr 2023

Hydrothermal Liquefaction Of Saccharina Latissima For The Production Of Biofuel, Mayokun A. Oke

Mechanical Engineering Theses

We performed hydrothermal liquefaction of brown macroalga (Saccharina latissima) in the presence of homogenous and heterogenous catalysts such as KOH, Na2CO3, Pd/C, HZSM-5, Ce/HZSM-5, and Ni/SiO2-Al2O3 in hot compressed water, to investigate their effects on product yield and composition in the biocrude. To investigate hydrocarbon production, we used methanol as co-solvent (methanol-to-water 1/4 vol.%) and as the only liquefaction solvent. We carried out the experiments in a batch reactor at 330oC and 120-130 bar, and varying temperature, algae-to-water ratio, residence time, and pretreatment method. The biocrude yields …


Montana Bureau Of Mines And Geology Butte Alluvial And Bedrock Controlled Groundwater Area Monitoring 2022 Data Summary Report, Montana Bureau Of Mines And Geology Apr 2023

Montana Bureau Of Mines And Geology Butte Alluvial And Bedrock Controlled Groundwater Area Monitoring 2022 Data Summary Report, Montana Bureau Of Mines And Geology

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Modeling Immune System Dynamics During Hiv Infection And Treatment With Differential Equations, Nicole Rychagov Apr 2023

Modeling Immune System Dynamics During Hiv Infection And Treatment With Differential Equations, Nicole Rychagov

CODEE Journal

An inquiry-based project that discusses immune system dynamics during HIV infection using differential equations is presented. The complex interactions between healthy T-cells, latently infected T-cells, actively infected T-cells, and the HIV virus are modeled using four nonlinear differential equations. The model is adapted to simulate long term HIV dynamics, including the AIDS state, and is used to simulate the long term effects of the traditional antiretroviral therapy (ART). The model is also used to test viral rebound over time of combined application of ART and a new drug that blocks the reactivation of the viral genome in the infected cells …


Sharprazor: Automatic Removal Of Hair And Ruler Marks From Dermoscopy Images, Reda Kasmi, Jason Hagerty, Reagan Harris Young, Norsang Lama, Januka Nepal, Jessica Miinch, William V. Stoecker, R. Joe Stanley Apr 2023

Sharprazor: Automatic Removal Of Hair And Ruler Marks From Dermoscopy Images, Reda Kasmi, Jason Hagerty, Reagan Harris Young, Norsang Lama, Januka Nepal, Jessica Miinch, William V. Stoecker, R. Joe Stanley

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Background: The removal of hair and ruler marks is critical in handcrafted image analysis of dermoscopic skin lesions. No other dermoscopic artifacts cause more problems in segmentation and structure detection. Purpose: The aim of the work is to detect both white and black hair, artifacts and finally inpaint correctly the image. Method: We introduce a new algorithm: SharpRazor, to detect hair and ruler marks and remove them from the image. Our multiple-filter approach detects hairs of varying widths within varying backgrounds, while avoiding detection of vessels and bubbles. The proposed algorithm utilizes grayscale plane modification, hair enhancement, segmentation using tri-directional …


Jwst’S Pearls: Dust Attenuation And Gravitational Lensing In The Backlit-Galaxy System Vv 191, William C. Keel, Rogier A. Windhorst, Rolf A. Jansen, Seth H. Cohen, Jake Summers, Benne Holwerda, Sarah T. Bradford, Clayton D. Robertson, Giovanni Ferrami, Stuart Wyithe, Haojing Yan, Christopher J. Conselice, Simon P. Driver, Aaron Robotham, Norman A. Grogin, Christopher N. A. Willmer, Anton M. Koekemoer, Brenda L. Frye, Nimish P. Hathi, Russell E. Ryan Jr., Nor Pirzkal, Madeline A. Marshall, Dan Coe, Jose M. Diego, Thomas J. Broadhurst, Michael J. Rutkowski, Lifan Wang, S. P. Willner, Andreea Petric, Cheng Cheng, Adi Zitrin Apr 2023

Jwst’S Pearls: Dust Attenuation And Gravitational Lensing In The Backlit-Galaxy System Vv 191, William C. Keel, Rogier A. Windhorst, Rolf A. Jansen, Seth H. Cohen, Jake Summers, Benne Holwerda, Sarah T. Bradford, Clayton D. Robertson, Giovanni Ferrami, Stuart Wyithe, Haojing Yan, Christopher J. Conselice, Simon P. Driver, Aaron Robotham, Norman A. Grogin, Christopher N. A. Willmer, Anton M. Koekemoer, Brenda L. Frye, Nimish P. Hathi, Russell E. Ryan Jr., Nor Pirzkal, Madeline A. Marshall, Dan Coe, Jose M. Diego, Thomas J. Broadhurst, Michael J. Rutkowski, Lifan Wang, S. P. Willner, Andreea Petric, Cheng Cheng, Adi Zitrin

Faculty and Staff Scholarship

We present the first JWST observations of the z = 4.11 luminous radio galaxy TN J1338–1942, obtained as part of the ‘Prime Extragalactic Areas for Reionization and Lensing Science’ (‘PEARLS’) project. Our NIRCam observations, designed to probe the key rest-frame optical continuum and emission line features at this redshift, enable resolved spectral energy distribution modelling that incorporates both a range of stellar population assumptions and radiative shock models. With an estimated stellar mass of log10(M/M⊙) ∼ 10.9, TN J1338–1942 is confirmed to be one of the most massive galaxies known at this epoch. Our observations also reveal extremely high equivalent-width …


Consumers And Eco-Labels: A Quantitative Analysis Of The Effects Of Various Sustainability Certification Models On Consumer Opinions, William F. Joseph Apr 2023

Consumers And Eco-Labels: A Quantitative Analysis Of The Effects Of Various Sustainability Certification Models On Consumer Opinions, William F. Joseph

Senior Theses

This research consists of an econometric analysis of the efficacy of a privatized sustainability certification model versus a proposed government-endorsed sustainability certification model within the United Sates market. Today, the widely accepted model of sustainability certification is constituted by a large market of private certifiers. By analyzing the effects of the current model and alongside the effects of a hypothetical government-endorsed system on consumer preferences for sustainably produced goods, the thesis aims to motivate further discussion into the possible benefit of adopting a government-sponsored sustainability certification system. In general, analysis of the data suggests much more promising and significant effects …


Modeling The Probability Of A Successful Stolen Base Attempt In Major League Baseball, Cade Stanley Apr 2023

Modeling The Probability Of A Successful Stolen Base Attempt In Major League Baseball, Cade Stanley

Senior Theses

In Major League Baseball (MLB), the outcome of a stolen base attempt has important implications. Success moves the runner closer to scoring, while failure records an out and removes the runner from the basepaths altogether. Therefore, it is important that the decision by a coach or player to steal a base is well-informed. In this thesis, I explore a statistical approach to making this decision. I train logistic regression and random forest models, using data about the game situation and about the runner, pitcher, and catcher involved in the stolen base attempt, to estimate the probability that a stolen base …


Templates To Transition: Making Solar-Generated Electricity Accessible For Lagos Residents, Adeola O. Adebajo Apr 2023

Templates To Transition: Making Solar-Generated Electricity Accessible For Lagos Residents, Adeola O. Adebajo

Senior Theses

According to the EPA, direct energy production results in at least 25% of the world’s emissions. This refers to emissions produced by burning coal, natural gas, and oil for electricity and heat. With the increasing effects of climate change, sustainable energy is becoming increasingly important as the world shifts away from fossil fuels. However, implementation of renewable energy sources is not as fast or as widespread as necessary. This paper aims to identify feasible solutions to the problem of renewable energy affordability in Nigeria especially in growing megacities like Lagos to ensure long lasting and climatefriendly energy sources. Two major …


Synthesis And Characterization Of Some Disubstituted Cyclopentadienyl Rhenium Complexes As Potential Candidates In Semiconductive Materials, Chloe Vernon Apr 2023

Synthesis And Characterization Of Some Disubstituted Cyclopentadienyl Rhenium Complexes As Potential Candidates In Semiconductive Materials, Chloe Vernon

Senior Honors Theses

Since 2000, when the Nobel Prize in Chemistry as awarded for conductive polymer research few studies have been performed concerning the conductive capabilities of discrete organometallic compounds. For this project, organometallic compounds were formed specifically with a transition metal included in the structure. Through oxidation and reduction reactions, the variation in the electrical conductivity could allow for an analysis of whether this unique structure would allow for tunability. The goal of this research was to begin with aromatic substituted fulvenes and perform various multistep synthesis processes, utilizing thallium salt intermediates, to produce several disubstituted cyclopentadienyl rhenium complexes. In this project, …


An Analysis Of Successful Sqlia For Future Evolutionary Prediction, Andrew Pechin Apr 2023

An Analysis Of Successful Sqlia For Future Evolutionary Prediction, Andrew Pechin

Senior Honors Theses

Web applications are a fundamental component of the internet, many interact with backend databases. Securing web applications and their databases from hackers should be a top priority for cybersecurity researchers. Structured Query Language (SQL) injection attacks (SQLIA) constitute a significant threat to web applications. They can hijack the backend databases to steal personally identifiable information (PII), initiate scams, or launch more sophisticated cyberattacks. SQLIA has evolved since its conception in the early 2000s and will continue to do so in the coming years. This paper analyzes past literature and successful SQLIA from specific time periods to identify themes and methods …


Prevalence Of Sars-Cov-2 Antibodies In Liberty University Student Population, Emily Bonus Apr 2023

Prevalence Of Sars-Cov-2 Antibodies In Liberty University Student Population, Emily Bonus

Senior Honors Theses

In 2020, the virus SARS-CoV-2 gained attention as it spread around the world. Its antibodies are poorly understood, and little research focuses on those with few COVID-19 complications yet large numbers of close contacts: university students. This longitudinal study recorded SARS-CoV-2 antibody presence in 107 undergraduate Liberty University students twice during early 2021. After extensive data cleaning and the application of various statistical tests and ANOVAs, the data seems to show that in the case of COVID-19 infections, SARS-CoV-2 IgM antibodies are immediately produced, and then IgG antibodies follow later. However, the COVID-19 vaccine causes the production of both IgM …


Unique Factorization In The Rings Of Integers Of Quadratic Fields: A Method Of Proof, Zachary Warren Apr 2023

Unique Factorization In The Rings Of Integers Of Quadratic Fields: A Method Of Proof, Zachary Warren

Senior Honors Theses

It is a well-known property of the integers, that given any nonzero aZ, where a is not a unit, we are able to write a as a unique product of prime numbers. This is because the Fundamental Theorem of Arithmetic (FTA) holds in the integers and guarantees (1) that such a factorization exists, and (2) that it is unique. As we look at other domains, however, specifically those of the form O(√D) = {a + bD | a, bZ, D a negative, squarefree integer}, we find that …


The Climate Change Hope Scale: Does The Three-Factor Model Fit An Adult Sample?, Yuhan Bi, Victoria Angulo, Michal Newhouse-Van Vlerin, Orei Z. Odents, Kimberly A. Barchard Apr 2023

The Climate Change Hope Scale: Does The Three-Factor Model Fit An Adult Sample?, Yuhan Bi, Victoria Angulo, Michal Newhouse-Van Vlerin, Orei Z. Odents, Kimberly A. Barchard

Psychology Faculty Presentations

The Climate Change Hope Scale (CCHS; Li & Monroe, 2017) adapted Synder et al.'s (1991) Hope Scale to focus specifically on climate change. In an adolescent sample, the CCHS has three factors: Personal-sphere willpower and waypower, Collective-sphere willpower and waypower, and Lack of willpower and waypower. Our research tests if Li and Monroe's (2017) three-factor model fits the data from an adult sample.


Phenotypic And Target-Based Drug Discovery, Angelica Veronica Carmona Apr 2023

Phenotypic And Target-Based Drug Discovery, Angelica Veronica Carmona

Theses & Dissertations

Batten Disease or Neuronal Ceroid Lipofuscinosis (NCL) is a group of rare, fatal, inherited pediatric neurodegenerative lysosomal storage disorders. NCLs are characterized by intracellular accumulation of an auto-fluorescent lipopigment called ceroid lipofuscin and neurodegeneration. Several forms of NCLs exist, some of which share some of the same features and symptoms but vary in severity and onset of symptoms with respect to age. Some common symptoms include progressive loss of vision, mental and motor deterioration, epileptic seizures, premature death, and in the rare adult-onset, dementia. Subtypes of NCLs occur when one of 13 different genes are mutated, and only two subtypes …


Concept Validation: Collecting Composite Samples To Understand The Presence Of Per- And Polyfluoroalkyl Substances (Pfas) In Michigan Forested Areas, Nicole Renee Sanabria Apr 2023

Concept Validation: Collecting Composite Samples To Understand The Presence Of Per- And Polyfluoroalkyl Substances (Pfas) In Michigan Forested Areas, Nicole Renee Sanabria

Masters Theses

This research discusses the results of a state-wide study conducted by The Michigan Department of Environment, Great Lakes, and Energy to assess the presence of PFAS in shallow soils of state-owned forested areas in Michigan utilizing a composite sampling method. One sample collected from each of Michigan’s 83 counties reveals the presence of PFAS in all but one sample, with total PFAS concentrations ranging from non-detect to 2.016 μg/kg (dry weight). PFOS is generally detected at the highest concentrations, ranging from non-detect to 0.88 μg/kg, followed by PFBA, with concentrations ranging from non-detect to 0.69 μg/kg, and PFOA, with concentrations …


Galaxy And Mass Assembly (Gama): Low-Redshift Quasars And Inactive Galaxies Have Similar Neighbors, Maria B. Stone, Clare F. Wethers, Roberto De Propris, Jari Kotilainen, Nischal Acharya, Benne W. Holwerda, Jonathan Loveday, Steven Phillipps Apr 2023

Galaxy And Mass Assembly (Gama): Low-Redshift Quasars And Inactive Galaxies Have Similar Neighbors, Maria B. Stone, Clare F. Wethers, Roberto De Propris, Jari Kotilainen, Nischal Acharya, Benne W. Holwerda, Jonathan Loveday, Steven Phillipps

Faculty and Staff Scholarship

We explore the properties of galaxies in the proximity (within a ∼2 Mpc radius sphere) of Type I quasars at 0.1 <z <0.35, to check whether and how an active galaxy influences the properties of its neighbors. We further compare these with the properties of neighbors around inactive galaxies of the same mass and redshift within the same volume of space, using the Galaxy and Mass Assembly spectroscopic survey. Our observations reveal no significant difference in properties such as the number of neighbors, morphologies, stellar mass, star formation rates, and star formation history between the neighbors of quasars and those of the comparison sample. This implies that quasar activity in a host galaxy does not significantly affect its neighbors (e.g., via interactions with the jets). Our results suggest that quasar host galaxies do not strongly differ from the average galaxy within the specified mass and redshift range. Additionally, the implication of the relatively minor importance of the environmental effect on and from quasars is that nuclear activity is more likely triggered by internal and secular processes.


Ramanujan–Sato Series For 1/Π, Timothy Huber, Daniel Schultz, Dongxi Ye Apr 2023

Ramanujan–Sato Series For 1/Π, Timothy Huber, Daniel Schultz, Dongxi Ye

School of Mathematical & Statistical Sciences Faculty Publications

We compute Ramanujan–Sato series systematically in terms of Thompson series and their modular equations. A complete list of rational and quadratic series corresponding to singular values of the parameters is derived.


Statistical Clustering Of Networks With Additional Information, Paul Atandoh Apr 2023

Statistical Clustering Of Networks With Additional Information, Paul Atandoh

Dissertations

As the online market grows rapidly, many companies and researchers are interested in analyzing product review dataset which includes ratings and text review data. In the first project, we mainly focus on analyzing the text review data. In the current literature, it is common to use only text analysis tools to analyze review dataset. But in our work, we propose a method that utilizes both a text analysis method such as topic modeling and a statistical network model to build network among individuals and find interesting communities. We introduce a promising framework that incorporates topic modeling technique to define the …


Zonality In Graphs, Andrew Bowling Apr 2023

Zonality In Graphs, Andrew Bowling

Dissertations

Graph labeling and coloring are among the most popular areas of graph theory due to both the mathematical beauty of these subjects as well as their fascinating applications. While the topic of labeling vertices and edges of graphs has existed for over a century, it was not until 1966 when Alexander Rosa introduced a labeling, later called a graceful labeling, that brought the area of graph labeling to the forefront in graph theory. The subject of graph colorings, on the other hand, goes back to 1852 when the young British mathematician Francis Guthrie observed that the countries in a map …


Using Visual Imagery To Develop Multiplication Fact Strategies, Gina Kling Apr 2023

Using Visual Imagery To Develop Multiplication Fact Strategies, Gina Kling

Dissertations

The learning of basic facts, or the sums and products of numbers 0–10 and their related differences and quotients, has always been a high priority for elementary school teachers. While memorization of basic facts has been a hallmark of elementary school, current recommendations focus on a more nuanced development of fluency with these facts. Fluency is characterized by the ability to demonstrate flexibility, accuracy, efficiency, and appropriate strategy use. Despite recommendations to focus on strategy use, there is insufficient information on instructional approaches that are effective for developing strategies, particularly for multiplication facts. Using visual imagery with dot patterns has …


High-Dimensional Variable Selection Via Knockoffs Using Gradient Boosting, Amr Essam Mohamed Apr 2023

High-Dimensional Variable Selection Via Knockoffs Using Gradient Boosting, Amr Essam Mohamed

Dissertations

As data continue to grow rapidly in size and complexity, efficient and effective statistical methods are needed to detect the important variables/features. Variable selection is one of the most crucial problems in statistical applications. This problem arises when one wants to model the relationship between the response and the predictors. The goal is to reduce the number of variables to a minimal set of explanatory variables that are truly associated with the response of interest to improve the model accuracy. Effectively choosing the true influential variables and controlling the False Discovery Rate (FDR) without sacrificing power has been a challenge …


Socially Aware Natural Language Processing With Commonsense Reasoning And Fairness In Intelligent Systems, Sirwe Saeedi Apr 2023

Socially Aware Natural Language Processing With Commonsense Reasoning And Fairness In Intelligent Systems, Sirwe Saeedi

Dissertations

Although Artificial Intelligence (AI) promises to deliver ever more user-friendly consumer applications, recent mishaps involving fake information and biased treatment serve as vivid reminders of the pitfalls of AI. AI can harbor latent biases and flaws that can cause harm in diverse and unexpected ways. It is crucial to understand the reasons for, mechanisms behind, and circumstances under which AI can fail. For instance, a lack of commonsense reasoning can lead to biased or unfair decisions made by Machine Learning (ML) systems. For example, if an ML system is trained on data that is biased or unrepresentative of the real …