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Articles 31 - 60 of 19508

Full-Text Articles in Physical Sciences and Mathematics

Alternative Adjacency Matrices And Spatial Analysis, Jaeseong Hwang Jun 2024

Alternative Adjacency Matrices And Spatial Analysis, Jaeseong Hwang

Dissertations

Spatial analysis is essential for comprehending the spatial distribution of diseases and various phenomena across geographic regions. This study investigates the utilization of alternative adjacency matrices in spatial analysis, with a specific focus on implementing Poisson regression models. This study intricately explores the methodology behind constructing alternative weight matrices, specifying weight matrices, and comparing the performance of Poisson models using five different weight matrices.

The popular Poisson model model is described, and five different definitions of weight matrices are defined, which are the following: binary weight matrix, inverse distance weight matrix using Euclidean distance, Graph distance matrix, Path matrix, and …


Quasi-Monte Carlo Estimation For Functional Generalized Linear Mixed Models., Ruvini Kumari Jayamaha Hitihamilage Jun 2024

Quasi-Monte Carlo Estimation For Functional Generalized Linear Mixed Models., Ruvini Kumari Jayamaha Hitihamilage

Dissertations

Functional Data Analysis (FDA) is a topic of growing interest in the statistics community and is applied in a wide range of fields such as Anthropology, Epidemiology, Meteorology, Neurology and Engineering. The data in FDA are smooth curves or surfaces in time or space which can be conceptualized as functions. Because of the smooth nature of the data and the measurements are highly correlated, making the classical methods such as univariate or multivariate analysis are infeasible for such data. Functional data Analysis (FDA) deals with these kinds of more detailed, complex, and structured data.

In this dissertation, we propose a …


A Microgenetic Learning Analysis Of Contextuality In Reasoning About Exponential Modeling, Elahe Allahyari Jun 2024

A Microgenetic Learning Analysis Of Contextuality In Reasoning About Exponential Modeling, Elahe Allahyari

Dissertations

This work explores the complex cognitive processes students engage in when addressing contextual tasks requiring linear and exponential models. Grounded within Piagetian constructivism and the Knowledge in Pieces (KiP) epistemological perspective (diSessa, 1993, 2018), this empirical study in a clinical setting develops a Microgenetic Learning Analysis (MLA) of the reasoning of 14 students from an Algebra II course. It reveals the critical role of cognitive disequilibrium as an essential cognitive state for conceptual development and the process of reorganizing knowledge systems. The study uncovers the fluctuations in students’ reasoning patterns and the significant impact on students’ reasoning patterns of task-specific …


An Experimental Study Of Supervised Machine Learning Techniques For Minor Class Prediction Utilizing Kernel Density Estimation: Factors Impacting Model Performance, Abdullah Mana Alfarwan Jun 2024

An Experimental Study Of Supervised Machine Learning Techniques For Minor Class Prediction Utilizing Kernel Density Estimation: Factors Impacting Model Performance, Abdullah Mana Alfarwan

Dissertations

This dissertation examined classification outcome differences among four popular individual supervised machine learning (ISML) models (logistic regression, decision tree, support vector machine, and multilayer perceptron) when predicting minor class membership within imbalanced datasets. The study context and the theoretical population sampled focus on one aspect of the larger problem of student retention and dropout prediction in higher education (HE): identification.

This study differs from current literature by implementing an experimental design approach with simulated student data that closely mirrors HE situational and student data. Specifically, this study tested the predictive ability of the four ISML classification models (CLS) under experimentally …


Environmental Fate And Transport Of Pfas In Wastewater Treatment Plant Effluent Discharged To Rapid Infiltration Basins, Kai M. Trobisch Jun 2024

Environmental Fate And Transport Of Pfas In Wastewater Treatment Plant Effluent Discharged To Rapid Infiltration Basins, Kai M. Trobisch

Masters Theses

Fate and transport of per- and polyfluoroalkyl substances (PFAS) in wastewater treatment plant (WWTP) effluent discharged to rapid infiltration basins (RIBs) is investigated using data from 26 WWTPs in Michigan and numerical modeling to assess the role of air-water interface (AWI) sorption in modulating mass fluxes to the saturated zone. Analysis of RIB physical properties yields a median separation distance of 6.5 meters between land surface and the water table, and a continuum of area-normalized effluent fluxes ranging from 0.01 to 0.62 meters per day. A subset of WWTPs with RIBs indicate higher PFAS concentrations in groundwater than effluent with …


Moral Responsibility And Other Visceral Attitudes Of Western Michigan University Students Toward Food Waste, Quinn Heiser Jun 2024

Moral Responsibility And Other Visceral Attitudes Of Western Michigan University Students Toward Food Waste, Quinn Heiser

Masters Theses

Despite the large number of people that go hungry on a regular basis in America, food waste remains a looming issue, globally and nationally. Both American college students and the universities themselves contribute a large portion to the national food waste totals. A dichotomy that is especially curious is the difference between students who live on-campus and whose main source of meals is the dining centers, versus students who live off campus and rely mainly on groceries to make meals independently. However, food waste has seldom been studied in the context of the fact that college is a major transition …


A Tale Of Two Toroidal Graphs, Akshat Gulgulia Apr 2024

A Tale Of Two Toroidal Graphs, Akshat Gulgulia

Honors Theses

A graph is toroidal if it can be embedded on a torus which is a doughnut-shaped surface. Two well-known examples of toroidal graphs are the complete graph K5 and the complete bipartite graph K3,3. In this thesis we elucidate the association of the subject matter with two renowned enigmas in graph theory, namely the Five Princes Problem and the Three Utilities Problems. Additionally, we look at their association with several renowned theorems in topological graph theory. We explore the link between these two graphs and a contemporary labeling concept.


Finite State And Sequential Automata, Kriti Gulgulia Apr 2024

Finite State And Sequential Automata, Kriti Gulgulia

Honors Theses

No abstract provided.


Virtual Reality As An Adjunct To Behavior Therapy: A Systematic Literature Review, Alya Alharrasi Apr 2024

Virtual Reality As An Adjunct To Behavior Therapy: A Systematic Literature Review, Alya Alharrasi

Honors Theses

The World Health Organization (WHO) projects that by 2030, mental disorders will become the primary source of global disease burden [1]. Anxiety-related disorders, including specific phobias, post-traumatic stress disorder (PTSD), and various forms of general or specific anxiety, are the most rapidly growing mental health disorders worldwide [2]. In the United States (US), over 1 in 10 American youths are experiencing depression, resulting in a severe impact on their personal, academic, or professional encounters and social engagements [3]. Similarly, anxiety disorders affect up to one-third of the US population during their lifetime [4].

Due to the growth of mental health …


5675 Wiredcats Scouting Hub, Sebastian Smiley Apr 2024

5675 Wiredcats Scouting Hub, Sebastian Smiley

Honors Theses

The WiredCats Scouting Hub was created to provide FIRST team 5675 with an application that allows them to make more informed strategic decisions regarding their competitive play. The app synthesizes data from multiple sources, parsing multiple data formats into a single source of truth. It also presents data to users through graphs and charts and provides interactive tables. The application meets the requirements set forth by the leadership of team 5675, effectively providing the capabilities they seek.


Kalamazoo Nature Center Mobile Application, Jacob Tebben Apr 2024

Kalamazoo Nature Center Mobile Application, Jacob Tebben

Honors Theses

This project aimed to address the challenge of enhancing visitor engagement and information dissemination at the Kalamazoo Nature Center (KNC) through the development of an integrated mobile and desktop application system. This initiative arose due to the limitations posed by traditional mobile applications which often become outdated and need to be updated by a dedicated software team. This project was designed for any user of the KNC desktop app to be able to update content on the mobile app, without the need of a dedicated software team.

The mobile application was designed for visitor use, enabling them to access up-to-date …


A Petrological Characterization Of The Iutzi Member Of Lucas Formation, Michigan Basin, Moira Burns Apr 2024

A Petrological Characterization Of The Iutzi Member Of Lucas Formation, Michigan Basin, Moira Burns

Honors Theses

It is thought that most Phanerozoic dolomites form via the replacement of precursor calcium carbonate [CaCO3] with dolomite [CaMg(CO3)2] through a dissolution-precipitation reaction with a Mg-bearing fluid. Although this may be widely accepted, the timing, conditions, settings, and mechanisms associated with the dolomitization process are still strongly debated, resulting in the proposal of various dolomitization models. The association between evaporite minerals and dolomite in the rock record is common and has led many to propose a model genetically associating evaporative fluids and dolomitization. The evaporative model posits as marine fluids evaporate and become more …


Establishing Practical Equivalence Of Factor Loadings In Multigroup Confirmatory Factor Analysis, Christopher Edward Shank Apr 2024

Establishing Practical Equivalence Of Factor Loadings In Multigroup Confirmatory Factor Analysis, Christopher Edward Shank

Dissertations

This dissertation compares the performance of equivalence test (EQT) and null hypothesis test (NHT) procedures for identifying invariant and noninvariant factor loadings under a range of experimental manipulations. EQT is the statistically appropriate approach when the research goal is to find evidence of group similarity rather than group difference; despite this, the conventional approach to measurement invariance analysis relies upon NHT. EQT has proved effective for invariance detection using global model-data fit statistics in simulated and real-world data (Counsell et al., 2020) but its use in partial measurement invariance (PMI) analysis for evaluation of factor loading differences between groups has …


Probing Shielding Tensor Components Of Amino Acids Using Nuclear Magnetic Resonance, Shiva Agarwal, Sungsool Wi, Michael Famiano, John Miller, Zbigniew Chajecki Apr 2024

Probing Shielding Tensor Components Of Amino Acids Using Nuclear Magnetic Resonance, Shiva Agarwal, Sungsool Wi, Michael Famiano, John Miller, Zbigniew Chajecki

Waldo Library Student Exhibits

Amino acids combine to form proteins in living organisms; most are chiral. On Earth amino acids appear only in the L- form, which is likely due to the amplification of enantiomeric excess (ee). However, a small ee for the L-form of amino acids has been observed in meteorites that have fallen on Earth. One possibility for this ee is the effect of antisymmetric components of the magnetic shielding tensor for 14N nuclei in amino acids, which in NMR manifests as the antisymmetric chemical shift (ACS). This can result in preferential destruction of their D-form through interactions with polarized leptons (e.g., …


Hydrophobic Deep Eutectic Solvents: Liquid-Liquid Extraction Of Organic Water Pollutants, Abigail Louise Maletta Apr 2024

Hydrophobic Deep Eutectic Solvents: Liquid-Liquid Extraction Of Organic Water Pollutants, Abigail Louise Maletta

Masters Theses

Pollution is a topic of significant research within the scientific community. The massive demand for industrial processes to deliver the technology and resources we rely on has opened numerous avenues for pollutants to enter the environment, affecting air, water, soil, and the food chain. Oftentimes, these pathways are intertwined, and the interplay between water and air currents spreads pollution globally, creating a cascade of environmental impacts. Water, a vital resource for all forms of life, is particularly susceptible to industrial pollution. Among the most prevalent water pollutants are heavy metals, such as lead and mercury, and organic compounds, often released …


Comparison Of Atmospheric Pressure Chemical Ionization And Electrospray Ionization Mass Spectrometry For The Direct Analysis Of Hops Bittering Compounds, Chhiring Sherpa Apr 2024

Comparison Of Atmospheric Pressure Chemical Ionization And Electrospray Ionization Mass Spectrometry For The Direct Analysis Of Hops Bittering Compounds, Chhiring Sherpa

Masters Theses

Hops acids are essential components in the beer brewing process containing alpha acids (α-acids) and beta acids (β-acids) as the major hops bittering compounds. Quantifying these acids is vital for quality control and determining bitterness levels and hops variety profiles. Current industry standards, like High-Performance Liquid Chromatography with Ultraviolet detection (HPLC-UV) and Ultraviolet Spectroscopy (UV-Vis), though effective, are time-consuming and solvent-intensive, providing incomplete information.

This research introduces a novel method using mass spectrometry with atmospheric pressure chemical ionization (APCI-MS) to analyze hops bittering acids without chromatographic separations. This approach offers rapid analysis, high throughput, and eco-friendliness.

Comparison with direct electrospray …


Development Of An App For The Kalamazoo Nature Center, Ernest Au Dec 2023

Development Of An App For The Kalamazoo Nature Center, Ernest Au

Honors Theses

Kalamazoo Nature Center (KNC), which has been recognized by its peers as one of the top nature centers in the country, is home to over 14 miles of hiking trails winding through woods, wetlands, and prairies. There are numerous places/plots in KNC that have an interesting and impressive history besides being home to a variety of animals and hundreds of wildflowers and other plant life. To improve the visitor’s experience at KNC, we will design a software app via the senior capstone project at the department of Computer Science at WMU. As the first step towards establishing a reference model …


The Factors Affecting Fashion Trends Have Changing Over The Years By Different Age Groups & The Evolution Of Media., Omnahqiran Dazz Nov 2023

The Factors Affecting Fashion Trends Have Changing Over The Years By Different Age Groups & The Evolution Of Media., Omnahqiran Dazz

Honors Theses

Introduction:

Fashion trends undergo continuous evolution, influenced by factors such as age groups and the ever-changing landscape of media. This research delves into the intricate relationship between these elements. Initially driven by a passion for fashion, the project expanded to explore the profound impact of social media evolution over the past 15-20 years.

Objectives: Investigate changing fashion trends across age groups.

Examine the evolution of media.

Analyze the factors affecting current-day fashion trends.

Explore the influence of social media on fashion choices.

This study provides invaluable insights for fashion designers, brands, and retailers, aiding in the development of effective market …


Origin Of The Mega-Streamlined Morphology In Ne Africa And Arabia: Remote Sensing And Field-Based Investigations, Mohamed Samy Mohamed Elhebery Aug 2023

Origin Of The Mega-Streamlined Morphology In Ne Africa And Arabia: Remote Sensing And Field-Based Investigations, Mohamed Samy Mohamed Elhebery

Dissertations

Mega-streamlined landforms on Earth and Mars have been attributed to aeolian, glaciogenic, fluvial, and tectonic processes. Identifying the forces that shaped these landforms is paramount for understanding landscape evolution and constraining paleo-climate models and ice sheet reconstructions. Exhumed Late Ordovician glacial deposits and landscape of the North Gondwana are reported here for the first time from SE Egypt. Using field and remote sensing (Advanced Land Observing Satellite [ALOS], Phased Array L-band Synthetic Aperture Radar (PALSAR) radar, multispectral Landsat TM datasets, and digital elevation models (DEMs) I mapped the distribution of the Late Ordovician glacial features (i.e. deposits and landforms) in …


Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link Aug 2023

Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link

Masters Theses

Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated …


Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link Aug 2023

Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link

Masters Theses

Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated with …


On Phishing: Proposing A Host-Based Multi-Layer Passive/Active Anti-Phishing Approach Combating Counterfeit Websites, Wesam Harbi Fadheel Aug 2023

On Phishing: Proposing A Host-Based Multi-Layer Passive/Active Anti-Phishing Approach Combating Counterfeit Websites, Wesam Harbi Fadheel

Dissertations

Phishing is the starting point of most cyberattacks, mainly categorized as Email, Websites, Social Networks, Phone calls (Vishing), and SMS messaging (Smishing). Phishing refers to an attempt to collect sensitive data, typically in the form of usernames, passwords, credit card numbers, bank account information, etc., or other crucial facts, intending to use or sell the information obtained. Similar to how a fisherman uses bait to catch a fish, an attacker will pose as a trustworthy source to attract and deceive the victim.

This study explores the efficacy of host-side APT (Anti-Phishing Techniques) based onWebsite features like Lexical, Host-Based, or Content-Based …


Simulating Strongly Coupled Many-Body Systems With Quantum Algorithms, Manqoba Qedindaba Hlatshwayo Aug 2023

Simulating Strongly Coupled Many-Body Systems With Quantum Algorithms, Manqoba Qedindaba Hlatshwayo

Dissertations

The complexity of the nuclear many-body problem is a severe obstacle to finding a general and accurate numerical approach needed to simulate medium-mass and heavy nuclei. Even with the advent of exascale classical computing, the impediment of exponential growth of the Hilbert space renders the problem intractable for most classical calculations. In the last few years, quantum algorithms have become an attractive alternative for practitioners because quantum computers are more efficient in simulating quantum physics than classical computers. While a fully fault-tolerant universal quantum computer will not be realized soon, this dissertation explores quantum algorithms for simulating nuclear physics suitable …


Chemical And Genetic Composition Analysis Of Organic And Nonorganic Tortilla Chips, Aubrey White-Day Jun 2023

Chemical And Genetic Composition Analysis Of Organic And Nonorganic Tortilla Chips, Aubrey White-Day

Honors Theses

The aim of this study was to explore the chemical and genetic differences between organic and nonorganic tortilla chips using GC-MS and PCR. Twenty chip brands were selected: 10 organic and 10 nonorganic. A survey on shopping preferences was created and distributed to compare results of public opinion to experimental data. It yielded 212 responses. All organic chip brands, and one out of ten nonorganic chip brands, tested negative for GMOs. This study concluded that there are minimal chemical differences based on Jaccard similarity indicies and stark genetic differences between organic and nonorganic tortilla chips. In comparing statistical analyses to …


Learning Finite Mixture Of Ising Graphical Models, Chong Gu Jun 2023

Learning Finite Mixture Of Ising Graphical Models, Chong Gu

Dissertations

The Ising model is valuable in examining complex interactions within a system, but its estimation is challenging. In this work, we proposed penalized likelihood procedures to infer conditional dependence structure when observed data come from heterogeneous resources in high-dimensional setting. The proposed method can be efficiently implemented by taking advantage of coordinate-ascent, minorization–maximization principles and EM algorithm. A BIC-type criterion will be utilized for the selection of the tuning parameter in the penalized likelihood approaches. The effectiveness of the proposed method is supported by simulation studies and a real-world example.


Functional Generalized Linear Mixed Models, Harmony Luce Jun 2023

Functional Generalized Linear Mixed Models, Harmony Luce

Dissertations

With the advancements in data collection technologies, researchers in various fields such as epidemiology, chemometrics, and environmental science face the challenges of obtaining useful information from more detailed, complex, and intricately-structured data. Since the existing methods often are not suitable for such data, new statistical methods are developed to accommodate the complicated data structures.

As a part of such efforts, this dissertation proposes Functional Generalized Linear Mixed Model (FGLMM), which extends classical generalized linear mixed models to include functional covariates. Functional Data Analysis (FDA) is a rapidly developing area of statistics for data which can be naturally viewed as smooth …


Copper-Indazolate Nanojars: Synthesis And Characterization, Nicholas Alexander Rudell Jun 2023

Copper-Indazolate Nanojars: Synthesis And Characterization, Nicholas Alexander Rudell

Masters Theses

The field of synthetic supramolecular chemistry has exploded since the first syntheses of crown ethers by Charles Pedersen in the 1960s, leading to further development in the area of macrocycles and incorporation into a vast array of metal-organic structures. Supramolecular chemistry came to the forefront of science with the 1987 Nobel Prize in Chemistry, awarded jointly to Donald J. Cram, Jean-Marie Lehn, and Charles Pedersen “for their development and use of molecules with structure-specific interactions of high selectivity.”

Nanojars are supramolecular metal-organic complexes with a high affinity for hydrophilic anions and can efficiently transfer such anions from water into organic …


Nonparametric Tests For Replicated Latin Squares, Joseph Yang Jun 2023

Nonparametric Tests For Replicated Latin Squares, Joseph Yang

Dissertations

Two classes of nonparametric procedures for a replicated Latin square design that test for both general and increasing alternatives are developed. The two classes of procedures are similar in the sense that both transform the data so that existing well-known tests for randomized complete block designs can be utilized. On the other hand, the two classes differ in the way that the data is transformed - one class essentially aggregates the data while the other class aligns the data. Within these contexts, the exact distributions and asymptotic distributions are discussed, when applicable. The exact distributions are easily computed using the …


Evaluating The Performance Of Estimators In Sem And Irt With Ordinal Variables, Bo Klauth Jun 2023

Evaluating The Performance Of Estimators In Sem And Irt With Ordinal Variables, Bo Klauth

Dissertations

In conducting confirmatory factor analysis with ordered response items, the literature suggests that when the number of responses is five and item skewness (IS) is approximately normal, researchers can employ maximum likelihood with robust standard errors (MLR). However, MLR can yield biased factor loadings (FL) and FL standard errors (FLSE) when the variables are ordinal. Other estimators are available. Unweighted least squares and weighted least squares with adjusted mean and variance (ULSMV and WLSMV) are known as the estimators for CFA with ordinal variables (CFA-OV). Another estimator, marginal maximum likelihood (MML), is used in the item response theory (IRT), specifically …


The Luminous Power Of Accretion Disks In Active Galactic Nuclei, Imogen Jade Courtney Apr 2023

The Luminous Power Of Accretion Disks In Active Galactic Nuclei, Imogen Jade Courtney

Honors Theses

Active Galactic Nuclei (AGN) are the most luminous long-lived objects in the universe. The phenomenon of the immense luminosities we observe for AGN has interested physicists and astronomers for over a century and continues to fascinate scientists today. The work in this thesis aims to provide an introductory exploration of this phenomenon. This thesis uses a simple model of AGN accretion disks that was developed under the standard disk model proposed by Shakura & Sunyev in 1973 under the simplest assumptions. The model accurately demonstrates how physical parameters, such as the temperature, radiative flux, luminosity, and spectra, scale through an …