Digital Commons Network^™

"There Is Nothing Else Like It": The Innovative Personality Of Lowney Turner Handy, Nathan Crews

Masters Theses

No abstract provided.

An Assessment Of Schools' Wellness Policies And Teachers’ Perspectives And Confidence In Teaching Nutrition In Elementary Schools In Jeddah, Saudi Arabia, Asma Yahya

Masters Theses

Nutrition education in school can provide students with the knowledge and skills to improve their eating behavior and overall health. This study aimed to evaluate the content of school wellness policies and understand teacher perspectives about teaching nutrition education at their schools in Jeddah, Saudi Arabia. In 2020, electronic surveys were used to evaluate the wellness policies in 11 elementary all-female government schools and teachers’ perspectives about the nutrition education offered in three elementary all-female government schools. Sixty-one teachers and eleven principals participated in this study. Fisher’s exact tests were used to test the differences between teachers’ perspectives and their …

Bigheaded Carp Spatial Reproductive Dynamics And Population Genetics In Large River Tributaries, Samuel J. Schaick

Masters Theses

Fisheries managers are devoting considerable effort, time, and funding towards limiting the spread of invasive Bighead and Silver (bigheaded) Carp. A better understanding of factors that influence spatial patterns of bigheaded carp reproduction can help fisheries managers prevent their spread. To examine factors that influence spatial patterns of reproduction, we sampled ichthyoplankton using drift nets and larval push nets in three tributaries of the Illinois and Wabash Rivers March-September 2016-2018. We compared relative abundances of bigheaded carp eggs and larvae among tributaries using catch per unit effort (CPUE). Abiotic data were analyzed from individual study tributaries and pooled among tributaries …

Construct Validity Of The Teate Depression Inventory: Convergent And Discriminant Validity And Equivalence For Black/African American And White/Caucasian Samples, Dylin Coons

Masters Theses

The purpose of this study was to replicate the construct validity of a new measure of depression, the Teate Depression Inventory (TDI; Balsamo & Saggino, 2013), with the primary focus on Black/African American participants. Research has purported that Black/African Americans experience inequality in obtaining mental health care for internalizing disorders. This may partially be caused by errors in diagnosing these individuals with symptoms. Correctly diagnosing internalizing disorders is a critical step in obtaining appropriate treatment. More research on depression and anxiety is needed to enhance mental health practices by addressing the need for professionals to be culturally competent and conscious …

Exploring Secondary Students’ Abilities In Judging The Credibility Of Digital Content On The Internet, Katie Dailey

Masters Theses

The shift from print to digital environments has created an opportunity and responsibility for educators to focus on instructional planning and practices that reflects the growing complexity of online texts students helping to ensure that their students are information literate. The purpose of this qualitative study is to explore the how 83 eleventh grade high school English students judge the credibility of information on the internet. The researcher used methodological triangulation to qualitatively analyze by comparing and aligning data from the survey results, observations of students during class discussions, responses to class assignments, and the quality ratings of students’ think-aloud …

Therapeutic Dna: Delivery And As A Delivery Vehicle, Natalie J. Holl

Masters Theses

"A review of gene delivery methods and gene editing methods, as well as original research utilizing DNA as a delivery vehicle is presented in the following thesis. Thousands of diseases have been linked to genes. Gene therapy, either delivering therapeutic genes or editing DNA bases, has arisen as a treatment option with the potential to cure diseases, rather than just ease symptoms. Genes and editing tools need to be delivered to cells for these therapies to be effective and many techniques have been developed to address the issue of delivery. Nonviral and viral methods have been used to deliver nucleic …

Optical Fiber Based Integrity Test Of Civil Engineering Materials: Numerical Analysis, Ruoyu Zhong

Masters Theses

“Major advancement in Civil Engineering cannot be accomplished without the help of sensors. Among different types of sensors, fiber-optic sensor is known for its light weight, high accuracy, resolution, immunity to electromagnetic interference, and resistance to harsh environment. This research mainly focuses on fiber-optic sensor application on concrete structures as temperature sensor. Thermal Integrity Profiling (TIP) is a non-destructive integrity testing method which makes use of the hydration heat from the concrete curing process to detect defects within a drilled shaft. Any defect of concrete could result in a temperature anomaly in a drilled shaft. The accuracy of the current …

Soil-Water-Energy Nexus Of Green Roofs, Katherine Ann Bartels

Masters Theses

"As the urban landscape continues to sprawl into previously undeveloped land to accommodate population growth, the need to design cities that effectively manage urban stormwater is imperative for a sustainable future. Green roofs use rain-harvesting techniques to reduce urban stormwater discharge while simultaneously providing traditional roof services as well as several ecosystem services. However, green roof media design varies greatly among commercial applications, and little guidance is available to engineers when selecting the media for prospective green roofs. Efforts to maximize stormwater retention and enhance urban heat island mitigation capabilities of green roofs while concurrently reducing nutrient loading were examined …

Decoupled Finite Element Methods For General Steady Two-Dimensional Boussinesq Equations, Lioba Boveleth

Masters Theses

"This work presents two kinds of decoupled finite element methods for the steady natural convection problem in two dimensions. Firstly, the standard Galerkin finite element method is derived in detail stating algorithms needed for the realization in MATLAB. A numerical example verifies the error convergence. Secondly, using iteration, the Boussinesq equations are decoupled into the Navier-Stokes equations and a parabolic problem. The resulting problems are solved either in parallel or sequentially. Finally, the same numerical example as before is used to confirm the convergence and analyze the methods in terms of iteration performance. In addition to a higher flexibility and …

In-Situ X-Ray Imaging Of The Selective Laser Melting Process, Meelap M. Coday

Masters Theses

"Fusion-based metal additive manufacturing (AM) has garnered much interest in recent decades. Despite the popularity of fusion-based AM technologies such as selective laser melting (SLM), there are still fundamental questions and uncertainties that need to be addressed. In this work, we focus on the understanding of the undercooling in the SLM process and the uncertainties induced by the laser beam size, power, and scan speed. First, we report the estimation of undercooling in the SLM process from the solidification rate measured by in-situ high-speed synchrotron x-ray imaging, based on the dendrite growth velocity model. The undercooling changes as a function …

Shock Wave Propagation Behavior At Corners And Crosscuts In Five Small-Scale Tunnel Scenarios, David Pierre Doucet

Masters Theses

"Shock wave propagation in tunnels and other enclosed environments is substantially more complicated than in an open-air or even a surface detonation. There is still much to learn about how shock wave properties change as a wave propagates in an enclosed space, such as a mine tunnel, inside of a building, or city street. The geometry of the enclosure will have a large role in the propagation of the shock wave. This means that many different tunnel designs must be studied. This work tested five different designs using a modular small-scale model. The scenarios tested were Straight-line, Single Turn, Around …

Attack Detection And Mitigation In Mobile Robot Formations, Arnold Fernandes

Masters Theses

"A formation of cheap and agile robots can be deployed for space, mining, patrolling, search and rescue applications due to reduced system and mission cost, redundancy, improved system accuracy, reconfigurability, and structural flexibility. However, the performance of the formation can be altered by an adversary. Therefore, this thesis investigates the effect of adversarial inputs or attacks on a nonholonomic leader-follower-based robot formation and introduces novel detection and mitigation schemes.

First, an observer is designed for each robot in the formation in order to estimate its state vector and to compute the control law. Based on the healthy operation of the …

Analysis Of Energy Economy In Muon Catalyzed Fusion Considering External X-Ray Reactivation, Nishant Raghav Pillai

Masters Theses

"An analysis of the energy economy of a theoretical muon-catalyzed nuclear fusion system has been made by invoking the use of point kinetic equations, Monte Carlo radiation transport simulations, and from a review of existing literature on muon-catalyzed fusion. An external X-ray reactivation source is proposed as a novel way to increase the number of fusions per muon and thereby overcome the so-called alpha sticking problem that has long been considered the primary impediment to breakeven muon-catalyzed fusion power. Free electron lasers, synchrotrons and Wakefield accelerators are discussed as possible bright X-ray photon sources. The addition of an intense external …

Evaluation Of Engineering Properties Of Soil In Al Butayn, Mudarraj Al Qassim And Turubah - Hail Saudi Arabia, Turki Essam A. Sehly

Masters Theses

"Fractures, sinkhole, building cracks, and ground subsidence have spread in many regions of the Kingdom of Saudi Arabia, some of which are related to seismic activity, others due to the presence of unstable soils (collapsing soils and Expansive soils) and others because of faults, while others result from drawing groundwater at great rates. The current study has several facts related to the formation of cracks and landslides, including:
1) A general study of geomorphology and geology of the study areas.
2) The causes affecting the formation of cracks and subsidence.
3) Detailed geomorphological and geological studies of the locations of …

Design And Development Of Power Processing Units For Applications In Electrically-Propelled Satellite Systems, Kartikeya Jayadurga Prasad Veeramraju

Masters Theses

"Electrospray technology provides a way to ionize specialized liquids by applying high voltages across a sharp porous tip and a metallic mesh. This technology is widely used in the field of mass spectroscopy for generating ions for testing purposes. The dawn of nano-satellites posed new challenges in the miniaturization of many conventional satellite sub-systems. One significant challenge faced in such a process was the miniaturization of the propulsion system. Electrosprays have started to find their application in the field of Aerospace Engineering and now are formally known as Electrospray Thrusters. These thrusters provide high specific impulse and are attractive substitutes …

Data Analytics Of Natural Gas Injection Enhanced Oil Recovery For Unconventional Reservoirs, Ali Waqar

Masters Theses

"Unconventional Enhanced Oil recovery, via the injection of natural gas has attracted great attention, as studies and projects have shown to be promising. An overview of pertinent studies has been carried out. Core Scale Laboratory Experiments, Core Scale Simulation, Field Scale simulation and pilot projects are analyzed. Data is collected for Core, Reservoir, Operational, and recovery information. Thereafter, Data analysis techniques are applied to identify data ranges, distributions, trends, relationships, and to eventually reach conclusions.

Huff and Puff injection is the preferred mode of injection, delivering most promising results for unconventional reservoirs. Across all the studies, with increase in amount …

Evaluation Of Eor Potential Of Low Salinity Polymer In Enhancing Heavy Oil Recovery On The Alaska North Slope, Shize Yin

Masters Theses

"Alaska's North Slope (ANS) contains vast amount of viscous oil resources that have not been extracted. This study focuses on the investigation over the potential shown by low-salinity polymer flooding in improving the recovery of ANS heavy oil through laboratory experiments.

At the beginning, coreflooding experiments were performed with silica sandpacks. The synergy between low-salinity water flooding and polymer flooding was proved, and the low-salinity polymer showed a better performance than the normal-salinity polymer. Further, the sandpacks prepared with formation sand from an oilfield on the ANS was then employed so as to simulate the reservoir condition. A series of …

On Predicting Stopping Time Of Human Sequential Decision-Making Using Discounted Satisficing Heuristic, Mounica Devaguptapu

Masters Theses

“Human sequential decision-making involves two essential questions: (i) "what to choose next?", and (ii) "when to stop?". Assuming that the human agents choose an alternative according to their preference order, our goal is to model and learn how human agents choose their stopping time while making sequential decisions. In contrary to traditional assumptions in the literature regarding how humans exhibit satisficing behavior on instantaneous utilities, we assume that humans employ a discounted satisficing heuristic to compute their stopping time, i.e., the human agent stops working if the total accumulated utility goes beyond a dynamic threshold that gets discounted with time. …

Experimental Evaluation Of A Honeycomb Structure In Open Channel Flows, Kyle David Hix

Masters Theses

“Designing and controlling open channel flows presents many challenges. One such challenge is energy dissipation. This challenge is currently addressed by several means, including the use of honeycomb structures. Energy dissipation by honeycomb structures has been studied for pressurized conduit flows; however, their ability to dissipate energy in free-surface flows remains largely unexamined. This work introduces a comprehensive experimental study designed to estimate the energy dissipation through a honeycomb structure in a free-surface flow.

This work examined the energy dissipation for a range of flows, pipe lengths, and pipe diameters in two flumes. PVC pipes ranging from 6 inches to …

Computer Vision Based Deep Learning Models For Cyber Physical Systems, Muhammad Monjurul Karim

Masters Theses

“Cyber-Physical Systems (CPSs) are complex systems that integrate physical systems with their counterpart cyber components to form a close loop solution. Due to the ability of deep learning in providing sensor data-based models for analyzing physical systems, it has received increased interest in the CPS community in recent years. However, developing vision data-based deep learning models for CPSs remains critical since the models heavily rely on intensive, tedious efforts of humans to annotate training data. Besides, most of the models have a high tradeoff between quality and computational cost. This research studies deep learning algorithms to achieve affordable and upgradable …

Comparison Of Reynolds-Averaged Navier-Stokes Turbulence Models For Simulating Boundary Layers In Hypersonic Flows, Jorge-Valentino Kurose Bretzke

Masters Theses

“This study describes the use of Computational Fluid Dynamics (CFD) codes to simulate hypersonic boundary layers using several different turbulent closure models and comparing Reynolds-Averaged Navier-Stokes (RANS) simulations against Direct Numerical Simulations (DNS) of similar test cases. The test cases in this study consist of a flat plate in a Mach 8 freestream with a zero pressure gradient and wall recovery ratio of 0.48, as well as a Mach 8 axisymmetric nozzle also with a cold wall. The RANS models used in this study are the Spalart-Allmaras model, Baldwin-Lomax model, Menter K-Omega Baseline and Menter K-Omega Shear Stress Transport models. …

Determining Variable Depth To Bedrock Using Ert And Masw: A Geophysical Investigation In St. Louis, Mo, Justin James Clinton

Masters Theses

“The research involves a geophysical study in the Maremec River Valley in St. Louis County, Missouri. The geophysical methods described in this paper can provide a relatively quick, inexpensive, and accurate means in investigating the lithologic characteristics of the subsurface. Method selection is ultimately dependent of the type of investigation and site-specific characteristics. In this investigation, Electrical Resistivity Tomography (ERT) data and Mutli-Channel Analysis of Surface Waves (MASW) data were acquired to image the bedrock beneath the Maremec River to an approximate depth of 110 ft or an elevation of 300 ft for a proposed wastewater tunnel. Two overlapping dipole-dipole …

On The Investigation Of Hot Tearing Behavior Of Continuous Cast Steel, Yanru Lu

Masters Theses

”Hot tearing has long been recognized as a major problem that plagues the development of the continuous casting process and results in low-quality products. Understanding of the mechanisms and the required conditions for the hot tearing formation is important for industries but has not been well-established yet. Thus, this research focuses on the hot tearing issue observed in continuous cast steel, by providing a summary of the current research progress and then introducing a new laboratory method to determine the thermo-mechanical properties relevant to hot tearing of different steel grades under different solidification conditions. In this method, an apparatus was …

Aquatic Plants And Their Application To Successful Floating Treatment Wetlands, Katherine May Mazanec

Masters Theses

“This research aims to mitigate eutrophication of freshwater habitats affected by urban stormwater runoff. Two highly impacted urban ponds near the Missouri S&T campus in Rolla were the focus of this research on the application of floating treatment wetlands (FTWs). An FTW consists of a man-made floating mat that is planted with emergent or floating macrophytes. The plants grow on the mat and their roots extend into the water column below the mat. Plant tissues, especially roots in direct contact with the water, take up nutrients, act as biofilm growth sites, and may facilitate precipitation of nutrients. With urbanization, ponds …

The Role Of Tectonic Inheritance, Plate-Reorganization, And Magma Flare-Ups In The Evolution Of The Sevier Orogeny, J. Daniel Quick

Masters Theses

"The temporal and spatial distribution of strain associated with the Sevier Orogeny in western North America is significantly different in the southern end of the belt, at the latitude of Las Vegas, than further to the north at the latitude of Salt Lake City. Until this study, reasons for these differences were speculative as a lack of thrust kinematic data in the intervening region hindered along strike correlation across the belt. A crystallization age of 100.18 ± 14 0.04 Ma was determined for zircons extracted from a recently recognized ash fall tuff near the base of the synorogenic Iron Springs …

Evaluation Of The Symbiotic Relation Between Endophyte And Poplar Trees Exposed To Landfill Leachate, Catalina Vega Hurtado

Masters Theses

“The contamination of soil and groundwater from leachate leakage from landfill has turned, nowadays, into a global public issue. One of the main concerns about this pollutant is the potential threat to human and ecosystem health. The current research studied endophyte bacteria in association with poplar trees (Populus sp.), as a method of bioremediation of landfill leachates. The objective of the project was to identify treatment strategies that may improve plant performance (survival rates, plant fitness, and degradation efficacy) with the purpose of being implemented in phytoremediation plots, aimed to intercept and treat landfill leachate, before the contamination of watershed. …

Link Between Energy Investment In Biosynthesis And Cellular Resistance To Oxidative Insult: Test The Cost-Quality Hypothesis In Insects, Taiwo Bolanle Iromini

Masters Theses

“The metabolic cost of growth is the amount of energy invested to fuel the anabolic biochemical reactions of biosynthesis. It has been implicated in the efficiency of farm animals and fishes, thus, increased economic profit. The metabolic cost of growth in the cockroach nymph was reported to be 20-fold higher than that of the painted lady butterfly caterpillar. The cost-quality hypothesis was proposed to explain the extremely low biosynthesis energy cost in painted lady caterpillar when physiological and ecological processes the metabolic growth cost was attributed to could not. In this study, the cost-quality hypothesis was tested.

Midgut cells were …

Performance Evaluation Of Alsi10mg Fabricated By A Selective Laser Melting Process, David Michael Murphy

Masters Theses

“Selective laser melting is becoming a widely used additive manufacturing technique that melts metal powder in a layer by layer process in order to build a desired part or geometry. Like many additive processes, selective laser melting allows for fabrication of parts with complex geometries. In order to fabricate a fully dense part there are a number of variables to take into account including: powder characteristics, laser parameters, and environmental parameters. Each of these variables can affect the microstructure and thus the mechanical performance of an additively manufactured part. In this work, the aluminum alloy AlSi10Mg was investigated. AlSi10Mg is …

Combining Laser Aided Ablation And Polishing To Minimize Surface Roughness Of Additively Manufactured Aluminium Components, Sahil Bipinkumar Patel

Masters Theses

“The surface roughness of additively manufactured parts is much higher than the acceptable range for most applications, thus post-processing is needed to qualify these parts for use. Laser polishing can be used to bring the surface roughness in an admissible range, but if the initial roughness is very high then the energy density for the polishing process needs to be very high to achieve a significant reduction in roughness. This high energy density can produce many process defects. Also, laser polishing alone cannot get rid of high wavelength asperities. Any waviness in the part can be linked with initial waviness …

3d Printing Reinforced Concrete Structures, Bryce Tyler Tafolla

Masters Theses

"This study aims to investigate a 3D printing method to directly incorporate continuous reinforcement into concrete structures. The ability to design and produce complex structures with optimized topographical configuration can be used to reduce potential material waste while maintaining the required structural strength. Furthermore, the ability to actively incorporate reinforcement into printed members substantially reduces potential labor requirements and eliminates the need to set up formwork.

The study began its initial approach with a manual extrusion process containing reinforcement to observe the necessary constraints required to achieve a printing system with this functionality. The second stage of development was designing …