Digital Commons Network^™

The Geodetic Strain Rates From Gnss In The North American-Carribean-Cocos Triple Junction In Guatemala And Implications For Seismic Hazard, Tanaya Kashyap

Masters Theses

"Geodetic velocity data are pivotal for deciphering seismic risks, providing initial constraints for crustal surface strain rates. Gaining an understanding of the 2D surface strain tensor across an entire area necessitates knowledge of the surface velocity field, yet geodetic data such as measurements from the Global Navigation Satellite System (GNSS) are dispersed across the Earth’s surface. In the current scope of study, we have employed various methodologies to estimate strain rates in Guatemala, utilizing GNSS velocity data and leveraging the open-source Python tool Strain_2D. Strain_2D facilitates the computation of strain rates through diverse methods applied to the same dataset and …

Investigating Accident-Tolerant Cladding In A Molten Salt-Cooled Micro-Reactor Using Multi-Physics Analysis And Uncertainty Quantification, Alexander Niles Foutch

Masters Theses

"Renewed interest in nuclear safety has resulted in development of accident-tolerant materials, such as cladding. Although developed for light water reactors, their use in more advanced reactors would save time and development costs for other new materials. This paper performed a Multiphysics investigation into the power profile, thermodynamics, heat transfer, and tensor mechanics of four candidate materials (Haynes 230, Zircaloy-4, FeCrAl, and SiC-SiC), using the highly benchmarked Kilo power design as an example of a high-temperature, highly enriched, sodium-cooled microreactor environment.

From neutronic code MCNP, no significant difference in power profile was found among the four. Using finite element software …

Discrete Event Simulation (Des) In Swapping/Charging Of Battery Electric Vehicles In Underground Mining, Albert Einstein Amponsem

Masters Theses

"With climate change concerns escalating, international agreements such as the Kyoto Protocol, the US Presidential Policy, and the Paris Agreement aim to reduce greenhouse gas (GHG) emissions, targeting significant reductions by 2050. The mining sector, a notable contributor to GHG emissions primarily through diesel-powered material haulage, emits approximately 68 million tons of CO₂ annually. Transitioning to Battery Electric Trucks (BETs) presents a viable mitigation strategy by replacing diesel trucks with electric alternatives, thus eliminating CO₂ emissions.

However, the effectiveness of BETs hinges on optimized battery swapping and charging procedures. This study employs Discrete Event Simulation (DES), a computational …

Environmental Health And Impact Of Workload On Errors For Wildland Fire Personnel, Michael Bryan Held

Masters Theses

"This thesis offers an analysis of how environmental health and workload affect wildland fire dispatchers and firefighters, combining results from two studies. The first study, "Environmental Health of Wildland Firefighters: A Scoping Review," performs a scoping review of scientific literature that examines the unique environmental health challenges wildland firefighters face. The review points out the increased risks to safety, health, and well-being from more exposure to natural hazards, identifying key research gaps and priorities. It stresses the need to broaden the geographic and demographic scope of studies, improve analytical methods, and increase research funding and focus for wildland firefighters.

The …

The Graduation Walk: Pareto Optimization Of Degree Paths, Arianna Gail Sy Chaves

Masters Theses

"A student’s academic history, course availability at their institution, and the overall degree of difficulty of the schedule for each semester are all critical factors in their academic success and experience. This thesis proposes an advanced recommendation algorithm that considers these real and conflicting factors that are involved in identifying a prudent degree path - a semester-by-semester course schedule to graduation - for each student. The original contribution of this work is the use of weighted-sum multi-objective constraint programming to minimize an increased number of optimization criteria and identify Pareto-optimal degree paths to be recommended to the student. The conflicting …

Metal-Ion Doped Borate Bioactive Glasses- A Novel Direction In Minimizing Nosocomial Infections And Antibiotic Resistance, Sarah Fakher

Masters Theses

"Nosocomial infections represent a formidable challenge and induce a substantial burden on patients and healthcare systems. These infections result from the interaction of numerous pathogenic microorganisms, particularly bacteria, and lead to increased morbidity, mortality, and healthcare costs. Extensive research has been carried out to devise innovative solutions, mainly focusing on antimicrobial natural and synthetic substances. However, the proclivity of bacterial strains to form biofilms complicates treatment and elevates antibiotic resistance, prompting research into pioneering more effective and versatile antibacterial strategies. Borate bioactive glasses (BBGs) are the latest, remarkable classes of biomaterials with a wide array of medical applications, owing to …

Human Arm Stiffness Estimation Method Developed For Overground Physical Interaction Experiments: Experimental Validation And Perspectives For Future Applications, Tarani Kanth Kamma

Masters Theses

"To build a physically interactive robot for overground applications, it is crucial to first understand the biomechanics of humans underlying overground physical human-robot interaction (pHRI) tasks. Estimating human arm stiffness during overground interactive tasks is a promising first step toward this goal. For this, an arm stiffness estimation technique was developed in our previous works that consider the unique challenges involving overground pHRI, such as the need to estimate the arm stiffness from a short duration of data with fewer repetitions. In this work, our stiffness estimation method is further validated with a passive spring setup with known stiffness values, …

Groundwater Movement In Boiling Spring, Onyx Spring, Yelton Spring, Wilkins Spring, Hudgens Spring And Natural Bridge Spring, Katherin Roxana Montes Chamorro

Masters Theses

"Onyx Spring, Boiling Spring, Yelton Spring, Wilkins Spring, Hudgens Spring, and Natural Spring are located on public land in Pulaski and Phelps County, Missouri. They were selected randomly to determine groundwater movement and compare water chemistry from the springs that are connected.

Using a dye tracing method, we were able to determine the direction of groundwater flow and a water multiparameter sonde was used to characterize the water chemistry at each point of the springs. As a result, from the six springs studied only three springs are connected which are Yelton, Onyx and Boiling Spring. Regarding to water chemistry this …

Computational Fluid Dynamics Analysis Of Thermal-Hydraulic Phenomena In Nuclear Reactor Systems, Mehedi Hasan Tusar

Masters Theses

"A computational analysis of thermal-hydraulic processes in nuclear reactor systems is performed, leveraging Computational Fluid Dynamics (CFD) to advance the design and ensure the safety of nuclear reactors. Divided into two primary sections, the initial part examines thermal-hydraulic behavior in the Replacement Research Reactor (RRR) operating at 20 megawatts and evaluates potential enhancements for the Missouri University of Science and Technology Reactor (MSTR) to operate at an increased capacity of 2 megawatts from the existing 0.2 megawatts. Detailed simulations reveal insights into flow characteristics, temperature distributions, and pressure drops, highlighting the effective use of realistic and porous media modeling techniques …

Iterative Power Flow Control Architecture For Dc-Ac-Ac Triple Active Bridge Converters: Design, Simulation, And Hardware Testing, Jonathan Henri Saelens

Masters Theses

Driven by widespread electrification and escalating energy demands, efficient and cost-effective converter systems are necessary to maintain and improve our nation's electrical grid. Facilitating this necessity are power electronic converters in applications such as smart grids, renewable energy integration, and electric vehicles. Guided by the demand for improved converter topologies and conversion efficiency, much research has been conducted on varying designs, development, and control implementations. One such topology gaining significant research attention is the triple active bridge (TAB) converter. The TAB is a three-port power converter enabling both bidirectional power flow on each port and galvanic isolation for safety and …

Fe-Ni-Cu-Pge Sulfide Transport Mechanisms And Carbon-Sulfur Interactions In Lower Crustal Magmatic Settings: A Study From The Valmaggia Ultramafic Pipe, Ivrea-Verbano Zone, Italy, Shelby Leann Clark

Masters Theses

"Constraining the processes that control the transport and deposition of sulfides in the deep lithosphere is an important step in expanding ore deposit exploration search space to include exhumed lower crustal rocks. The ultramafic sulfide ore-bearing Valmaggia pipe in the Ivrea-Verbano Zone of NW Italy, an exhumed cross section of the overlying lower continental crust and subcontinental lithospheric mantle, gives critical insight into metallogenic processes in lower crustal settings. The ~300 m wide metasomatized pipe hosts Fe-Ni-Cu-(PGE±Co±Au) sulfide mineralization that is commonly associated with locally abundant carbonates and hydrous silicates (phlogopite, amphibole). Previous studies suggested that sulfides were physically transported …

Dig Limits Optimization Using Binary Integer Linear Programming Method In Open Pit Mines, Hussam Naif Altalhi

Masters Theses

"Dig limits optimization is the process for classifying different materials (e.g., ore, stockpile material, and waste) into appropriately sized contiguous zones for open pit mining. The efficient determination of dig-limits is crucial for profitable and sustainable resource extraction in mining. Previous research has focused on defining dig-limits manually or using optimization approaches, but these methods are limited to only handling two material destinations (ore and waste). Thus, there is a need for operations research methods that consider the selectivity of mining equipment and can optimize dig-limits for metal mining operations with more than two material destinations. Consequently, the objective of …

Simulation Of Lc Circuits In Cylindrical Photoemission Driven Cavities Using Coupled Monte Carlo And Particle-In-Cell Codes, Ravi Sanjay Shastri

Masters Theses

"This work presents a computational experiment simulating irradiation of gold in a cylindrical cavity. The full 3-D simulation with a B-Dot diagnostic is modeled, and a subset of the results are compared to modeling the system as a coupled anode/cathode (AK) gap and transmission line. The cavity is filled with N2 and Ne gasses at pressures ranging from vacuum to 1000 mTorr. Space-charge limited emission physics, electric discharge physics, LC circuit physics, and Monte-Carlo methods are explored.

The computation process happens in two steps. First, the electron emission material is irradiated with an input x-ray photon spectrum to produce a …

A Binary Integer Linear Programming Model For Optimizing Underground Stope Layout, Theophilus Mensah

Masters Theses

"Underground mine planning engineers face significant challenges when determining what geometry provides the most profitable and safe stope for extraction. Several techniques and optimization algorithms have been developed in recent years, but most fail to find optimal solutions because they are heuristic or LP-based without efficient geometric constraints. This thesis work proposes a two-dimensional binary linear programming (BILP) model for determining the optimal combination of blocks in a stope that maximizes the economic value of the layout of stopes for a sublevel deposit. The work draws from Queyranne and Wolsey’s (2017 & 2018) formulations of tight constraints for bounded up/down …

Validation Of Athlet With Purdue University Multi-Dimensional Integral Test Assembly (Puma) Test, Emin Fatih Ozdem

Masters Theses

"Following the Three Mile Island Unit 2 (TMI-2) disaster, the development of a diagnostic system for emergency situations in a nuclear power plant was identified as an essential research area to strengthen the safety of nuclear power plants. A real-time estimation system of vital safety parameters on the main side of a PWR (Pressurized Water Reactor) facility was investigated since precise post-event scenario estimations are thought to be a crucial component of the diagnostic system. The alarm system of the plant can detect an SB-LOCA (Small Break Loss-Of-Coolant-Accident), but there were a couple of potential long-term transient occurrences. The accident …

Hysplit In Simulating The Atmospheric Dispersion Of Hazardous Aerosols: A Case Study In St. Louis, Missouri, Ahmet Tolga Odabasi

Masters Theses

"Atmospheric dispersion and transmission play an important role in the behavior and effects of air pollution. Human health can be adversely affected by air pollution in a variety of ways, both immediately and over time. The Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) modeling program, a computer model and software package, tracks the transport trajectories and distributions of air pollution and various pollutants, including radioactive pollutants, in the atmosphere. It also facilitates research on pollution sources. This study simulated the transport of hazardous aerosols in St. Louis region for the years 2020, 2021, and 2022 using the HYSPLIT modeling …

High Strain Rate Analysis Of 3d Printed Concrete As Compared To Conventionally Cast Concrete, Weston Mcleod Thomsen

Masters Theses

"3D Printed Concrete (3DPC) is a developing method of construction that has advantages over conventional methods, including formwork reduction, complex geometry, and expedited construction. This technology has potential benefits for the military when considering the austere environments that forward operating bases are built in. This study aims to assess 3DPC applications in protective structures that protect critical assets from explosive blasts. These protective structures experience a high-strain rate response during blast loading of the structure, and the effects of this have yet to be analyzed in the literature concerning 3DPC. With the lack of prior research, the focus here will …

Incarcerated To Educated: The On-Campus Experiences Of College Students Post Incarceration, Taylor Comer

Masters Theses

As reentry rates continue to climb in the United States, more individuals with felony convictions on their criminal records will be looking to obtain post-secondary education to make themselves more marketable in the workforce. The purpose of this narrative study was to examine the experiences of three individuals that pursued higher education after being released from prison. It was determined that the criminality of these individuals had minimal impact on their experiences in higher education, and that there are other components of their identity that have a heavier influence on their likelihood of success. The other components of their identities …

Social Gender Norms And Depression In College Students, Derek Deeney

Masters Theses

The primary purpose of this quantitative study was to determine if there was a relationship between the conformity to social gender norms (masculine and feminine) and depression among male and female college students at a mid-sized, four-year public institution in the Midwest. A secondary purpose was to investigate if there was a difference in depression between males and females, and if a there was a difference in conformity to social gender norms (masculine and feminine) between males and females. Understanding the trends in social norm conformity and depression can lead to changes in how faculty and staff in higher education …

The Role Of Study Abroad Directors In The Internationalization Of Higher Education, Alexandra Tserenova

Masters Theses

This study looks at the preparation and job description for those serving as directors of study abroad on the college campus. For this study three professionals who work in director positions were interviewed as well as their job descriptions were analyzed to determine what the expectations are for those in these positions. Study abroad professionals engage with students, faculty, external agencies, and other educational institutions worldwide. They are required to collaborate with many different constituents in the areas of program development, recruitment, risk management, program implementation, as well as pre- and post-departure orientations.

Exploring A Medicinal Strain Of White-Rot Fungus For Biofuel Applications, Kortney L. Lucius

Masters Theses

The major limitation to producing biofuels from lignocellulosic biomass, such as miscanthus straw, is the difficulty in accessing fermentable carbohydrates encased in lignin. Traditional methods for separating lignin are economically and environmentally costly. Biological pretreatment using white-rot fungi, such as Trametes versicolor, has been demonstrated to potentially reduce the need for harsh chemical and physical pretreatment methods. Despite these efforts, the process of converting lignocellulose to ethanol remains financially challenging. To explore a potential co-product for the process, this study evaluated the efficacy of T. versicolor strain CM-101, known for producing the valuable medicinal macromolecule polysaccharide-K (PSK), as a …

Synthesis Of A Basket-Shaped Host Molecule Based On P-Tert-Butylcalix[4]Arene Featuring Pyridinyl Groups For Volatile Guest Molecule, Boluwatife S. Ajewole

Masters Theses

Supramolecular and Molecular chemistry offer an expanding array of applications for the development of smart devices, with calixarene-based molecular baskets playing a pivotal role in host-guest chemistry. A key concept in this field is the design of "smart" molecules with gate-like features, which can selectively transport chemical or biochemical species that are volatile, reactive, or sensitive to typical solution environments. These molecular hosts are engineered with predefined groups that respond to external stimuli, such as changes in concentration, temperature, or pH.

Molecular baskets are synthetic host molecules designed to capture guest molecules selectively through adjustable gates. In our study, we …

Characterization Of The Kansas River Alluvial Aquifer Using Towed Transient Electromagnetic Geophysical Method, Jonathon Daniel Voss

Masters Theses

"Forecasted urban development areas west of Kansas City, Kansas in the coming decades has caused an increase of research into water resources (Butler et al. 2022). A location of investigation has been the Kansas River Alluvial Aquifer (KRAA) for shallow ground water resources. To investigate the KRAA structure and grain texture, the towed transient electromagnetic system (tTEM) in conjunction with direct push electrical conductivity logs and lithology wells were used to investigate four locations between Lawrence and Manhattan, Kansas. In total, 110 line-kilometers of tTEM data was collected. The tTEM data collected were high quality and through inversions of the …

Time Series Anomaly Detection Using Generative Adversarial Networks, Shyam Sundar Saravanan

Masters Theses

"Anomaly detection is widely used in network intrusion detection, autonomous driving, medical diagnosis, credit card frauds, etc. However, several key challenges remain open, such as lack of ground truth labels, presence of complex temporal patterns, and generalizing over different datasets. In this work, we propose TSI-GAN, an unsupervised anomaly detection model for time-series that can learn complex temporal patterns automatically and generalize well, i.e., no need for choosing dataset-specific parameters, making statistical assumptions about underlying data, or changing model architectures. To achieve these goals, we convert each input time-series into a sequence of 2D images using two encoding techniques with …

Evaluating The Influence Of Operator Practices On Hydraulic Shovel Productivity And Energy Consumption Using Telemetry Data, Noah Adekunle Aluko

Masters Theses

"Hydraulic shovels are increasingly being adopted in the mining industry, which is known for its significant energy consumption and carbon emissions. Technological improvements in hydraulic shovels aim at bolstering energy efficiency and productivity because of the drive to curb energy consumption and enhance energy efficiency. However, one aspect that is often overlooked is the vital role of operators. Although the influence of operators’ practices on excavators’ energy efficiency has been acknowledged in past studies, there is a paucity of quantitative research assessing this influence in the context of hydraulic shovels.

The main objectives of this study are to 1) develop …

The Deep Bsde Method, Daniel Kovach

Masters Theses

"The curse of dimensionality is the non-linear growth in computing time as the dimension of a problem increases. Using the Deep Backwards Stochastic Differential Equation (Deep BSDE) method developed in [HJE18], I approximate the solution at an initial time to a one-dimensional diffusion equation. Although we only approximate a one-dimensional equation, this method extends well to higher dimensions because it overcomes the curse of dimensionality by evaluating the given partial differential equation along "random characteristics''. In addition to the implementation, I also present most of the mathematical theory needed to understand this method"-- Abstract, p. iii

Radiofrequency Interference Detection Using Lstmand Statistical Analysis Discriminator, Luke Smith

Masters Theses

"Wireless devices are becoming increasingly pervasive across all aspects of society. Examples of such devices include radios, routers, mobile phones, tablets, and more. As the number of radio frequency (RF) devices continues to rise, so does the amount of interference and noise increase. This is why an efficient approach to interference detection is explored. Most research within this area has been done strictly within the frequency domain as viewing a signal within this domain provides many insights into what makes the signal. This has, however, led to the time domain being underutilized for this area of research.

To explore the …

Laboratory Scale Experimental Analysis Of The Effect Of Surfactants On Acid Mist Suppression During Copper Electrowinning, Thurman Kollie Elgin

Masters Theses

"The reduction in acid mist generation is an industrial occupational objective in the electrowinning industry of base metals. The technology of electrowinning as an extractive metallurgical technique of metals proficiently contributed to the recovery of pure base metals. During the process of electrowinning, oxygen bubbles are generated on the anode of the electrowinning cell because of the over potential in the cell due to high voltage. The bubbles formed tend to contain sulfuric acid of the electrolyte in the form of liquid-gas ascending particles of the solution. As these bubbles ascend to the surface of the solution, they burst at …

Processing & Properties Of Zirconium Carbide Manufactured By Ceramic On-Demand Extrusion, Clare Sabata

Masters Theses

"This research focuses on the development of a zirconium carbide (ZrC) paste for use in material extrusion direct ink write additive manufacturing (AM) followed by the pressure less densification of ZrC and the mechanical and thermal characterization of the resulting ceramics. A highly loaded, aqueous paste was developed using commercial ZrC powder ball milled to ~1 μm. Optimal dispersant, binder, and solids loading were found by rheological characterization. The paste composition consisted of 46-47 vol% ZrC, 43.5 vol% distilled water, 8.1 vol% dispersant, and 1.6 vol% binder. A yield stress of ~8 Pa allowed for shape retention upon removal of …

Microwave Materials Characterization Of Geopolymers, Jared Sinkey

Masters Theses

"The purpose of this work was to develop a process for studying geopolymer materials using a microwave materials characterization approach. Such an approach is known to provide information about chemical and physical properties of materials. As such, in this work, the focus is on the role of water in the geopolymer curing process. To do this, specimens were prepared and cast and microwave measurements conducted throughout the curing process using a short-circuited rectangular waveguide (SC-RWG) measurement technique. In this technique, the complex reflection properties/coefficient of the sample are measured. The effect of sample length and dielectric properties on materials characterization …