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Investigation Into Karst Of Southwest Missouri Using Electrical Resistivity, Donald Zachary Wormington

Graduate Theses/Dissertations

Nixa, Missouri is located on the southwestern edge of the Ozark Dome which has a karst geomorphological environment. Near surface geophysical methods can be used in determining the location and nature of karst features such as caves and sinkholes. Electrical resistivity methods have been shown to be among the most useful methods in deciphering sinkholes and caves. To investigate a known cave and related sinkholes and faults within Mississippian carbonates south of Nixa, Missouri, a series of two-dimensional electrical resistivity profiles were collected using the dipole-dipole and Schlumberger arrays. Terrain data was collected to include in modeling. The data were …

Vision-Based Human Fall Detection In Smart Homes, Snigdha Chaudhari

Graduate Theses/Dissertations

Falling is one of the leading causes of death from unintentional injuries in older adults. They are more common in people over the age of 65. Wearable sensor-based solutions are commercially available, but they possess limitations like recharging the sensors, and wearing them can be intrusive to the user. Consequently, vision-based fall detection approaches offer a feasible alternative due to the ever-increasing presence of cameras in smart homes. This thesis presents a novel two-stage human fall detection system for smart homes. The proposed approach uses humans as a sensor. It is a vision-based two-stage process where Stage-1 is dedicated to …

Modeling Strategy For Emi Filter And Flyback Transformer, Ruijie He

Doctoral Dissertations

“The switch-mode power supply is key to miniaturizing power adapters. However, the switching nature of the circuit introduces issues in conducted emissions. In a flyback converter, the transformer serves as the path for common mode current flowing from the primary side to the secondary side. Different winding technologies have been invented and implemented to reduce the capacitance between the primary side and the secondary side. But the repeatability of the winding is still poor due to the fluctuations of the winding machine. Thus, the resulting conducted emission has a fluctuation that can lead to failure in the compliance tests. EMI …

Characterization And Modeling Of Esd Events, Risk And Protection, Jianchi Zhou

Doctoral Dissertations

“The ESD (Electrostatic discharge) failures have been raising critical reliability problems in electronic devices design. However, not all the ESD scenarios have been specified by the IEC standard and the characterizations of the ESD risk for different scenarios are essential to evaluate the ESD robustness of the devices in the real word.

The insulation of plastic enclosures provides protection against ESD to the electronic system inside. However, seams between plastic parts are often unavoidable. Different plastic arrangements are constructed to investigate the spark length and current derivatives and to understand the ESD spark behavior for geometries having spark lengths longer …

Exhibition: Land Of Immortals 众神之地, Yi Bing (Bing-Yi Huang) 黄冰逸

Zhou Documents

This document is a Chinese version outline for the artist’s exhibition Land of Immortals (众神之地). The exhibition was held in NewYork during Asia Week, and co-presented by INK studio (墨斋) and Joan B. Mirviss Gallery. It centers on Bingyi’s research journey through the Taihang Mountain. The text mainly introduces the four series on view—Eight Views of Bewilderment (罔象八景), Land of Immortals (众神之地), Eyes of Chaos (混沌之眼), and handscroll The Other Shore. Through her distinctive ink language, she weaves Han dynasty cosmology, Song dynasty traditional landscape and Taoism-Buddhist philosophy together. It also includes brief institutional introductions for the artist and Joan …

Global Modeling Of Millimeter-Wave Transistors: Analysis Of Electromagnetic-Wave Propagation Effects, Soheil Nouri, Samir M. El-Ghazaly

Electrical Engineering Faculty Publications and Presentations

In this study, the transmission line concept and the electron transport theory are consolidated in a global modeling approach, the wave-electron-transport (WET) model, to account for the physical phenomena in millimeter-wave devices. No equivalent circuit model is required to represent the innate properties of the device. Hence, the model is reliable for both small- and large-signal analyses. The electrodes of a transistor act as coupled multi-conductor transmission lines at millimeter-wave bands. The WET model consists of a device solver to obtain solutions for carrier-transport equations of the intrinsic device, and an electromagnetic solver (EM solver) to provide solutions for the …

Modular Expandable Multiinput Multioutput (Mimo) High Step-Up Transformerless Dc-Dc Converter, Zahra Saadatizadeh, Pedram Chavoshipour Heris, H. Alan Mantooth

Electrical Engineering Faculty Publications and Presentations

In this paper, a Multi-Input Multi-Output (MIMO) high step-up transformerless DC-DC converter is proposed. The proposed converter can expand the number of ports from both input and output terminals. Also, it has a modular structure using voltage multiplier cells (a switch, two diodes, a capacitor, and an inductor). The proposed converter is useful for a wide range of applications and has the merit of interfacing multiple hybrid voltage sources with each other to supply different loads with various voltage levels. All the output voltages of the output ports can be regulated at the same time by tuning separate controlling parameters. …

An Efficient Electro-Thermal Compact Mode Of Sic Power Mosfets Including Third Quadrant Behavior, Arman Ur Rashid, Md Maksudul Hossain, Yuheng Wu, Hayden Seth Carlton, H. Alan Mantooth, Britt Brooks

Electrical Engineering Faculty Publications and Presentations

This paper presents an efficient physics-based electro-thermal model that solves some advanced problems of modeling Silicon Carbide (SiC) power MOSFETs. It is the first electro-thermal model that simulates the temperature dependency of the first and the third quadrant characteristics, including the reverse recovery of the body diode accurately and efficiently. It extends from a previous work that demonstrated the isothermal physics-based model of the gate-dependent body diode. Physics-based temperature scaling of the first and third quadrant allows simulation of the self-heating effect in a wide range of temperatures (27 °C–200 °C), even for the synchronous operation. Moreover, a physics-based modeling …

Response Of Antarctic Soil Fauna To Climate-Driven Changes Since The Last Glacial Maximum, Andre L.C. Franco, Byron J. Adams, Melisa A. Diaz, Nathan P. Lemoine, Nicholas B. Dragone, Noah Fierer, W. Berry Lyons, Ian Hogg, Diana H. Wall

Biological Sciences Faculty Research and Publications

Understanding how terrestrial biotic communities have responded to glacial recession since the Last Glacial Maximum (LGM) can inform present and future responses of biota to climate change. In Antarctica, the Transantarctic Mountains (TAM) have experienced massive environmental changes associated with glacial retreat since the LGM, yet we have few clues as to how its soil invertebrate-dominated animal communities have responded. Here, we surveyed soil invertebrate fauna from above and below proposed LGM elevations along transects located at 12 features across the Shackleton Glacier region. Our transects captured gradients of surface ages possibly up to 4.5 million years and the soils …

Underwater Video As A Tool To Quantify Fish Density In Complex Coastal Habitats, Ronald Baker, Dakota Bilbrey, Aaron Bland, Frank D’Alonzo Iii, Hannah Ehrmann, Sharon Havard, Zoe Porter, Sarah Ramsden, Alexandra Rodriquez

University Faculty and Staff Publications

Habitat loss is a serious issue threatening biodiversity across the planet, including coastal habitats that support important fish populations. Many coastal areas have been extensively modified by the construction of infrastructure such as ports, seawalls, docks, and armored shorelines. In addition, habitat restoration and enhancement projects often include constructed breakwaters or reefs. Such infrastructure may have incidental or intended habitat values for fish, yet their physical complexity makes quantitatively sampling these habitats with traditional gears challenging. We used a fleet of unbaited underwater video cameras to quantify fish communities across a variety of constructed and natural habitats in Perdido and …

Study Of Contamination Resulting From Historical Mining Within The Old Lead Belt: Mineral Fork Watershed, 2021-2022, Tessa Nicole Mortensen

Masters Theses

“The Old Lead Belt in Missouri has been mined extensively over the past two hundred years, and with historical mining practices often not meeting modern environmental protection standards many areas have significant soil and water contamination as a result. This study focuses on the Mineral Fork River’s watershed in Washington County, Missouri, which includes portions of four separate Superfund sites. In this study, we exam the impact of historical mining on the health of alluvial systems, as evaluated by lead, zinc, and barium (barite) concentrations in the suspended and sediments within tributaries of the Mineral Fork River system. To relate …

Zinc Plating From Alkaline Non-Cyanide Bath, Abdul J. Mohammed

Masters Theses

“Alkaline non-cyanide zinc plating baths are preferred when trying to avoid the toxicity of cyanide baths or corrosivity of acid baths. Without additives, alkaline zincate baths produce powdery non-adherent deposits which have no use in commercial plating. Additives must be added at optimum concentrations to produce adherent, bright and uniform zinc deposits. In this study electrochemical tests were used to determine effects of additives on cathodic polarization, throwing power and morphology of deposits. Current density distribution in a unique bath of 37.5 g L^-1 Zn and 210 g L^-1 NaOH was modelled using COMSOL and validated two plating …

Particle Swarm Optimization For Critical Experiment Design, Cole Michael Kostelac

Masters Theses

“Critical experiments are used by nuclear data evaluators and criticality safety engineers to validate nuclear data and computational methods. Many of these experiments are designed to maximize the sensitivity to a certain nuclide-reaction pair in an energy range of interest. Traditionally, a parameter sweep is conducted over a set of experimental variables to find a configuration that is critical and maximally sensitive. As additional variables are added, the total number of configurations increases exponentially and quickly becomes prohibitively computationally expensive to calculate, especially using Monte Carlo methods.

This work presents the development of a particle swarm optimization algorithm to design …

Characterization Of Cermet Fuel For Nuclear Thermal Propulsion (Ntp), James Floyd Mudd

Masters Theses

“A manned flight to Mars is met with many technical challenges, not the least of which is the development of propulsion technology capable of moving a transit vehicle from Earth orbit to Mars orbit. NASA is investigating Nuclear Thermal Propulsion (NTP) as a way of reducing flight time and providing the option for a mid-mission abort. NTP, which uses a high temperature nuclear reactor to heat a propellant, requires advanced fuel materials capable of withstanding temperatures well in excess of 2000 K. Among the fuel options are ceramic metal (cermet) composites composed of refractory metals and Ultra-High Temperature Ceramics (UHTCs). …

Validation Of Athlet-Cd With Cora-28 Test, Murat Tuter

Masters Theses

“Following the incidents at Chernobyl and Fukushima, severe accidents at nuclear power plants (NPP) have become a global concern. These accidents generally occur because of a failure in the reactor cooling system (RCS) and result in the melting of the reactor core and fission product release. This event is mostly caused by a LOCA, loss of flow accident, station blackout or loss of heat sink. During a severe accident, generation of hydrogen as a result of steam-zircaloy fuel cladding is a significant safety concern. To better understand and prevent the hydrogen generation issue, safety related experiments and safety related codes …

Several Problems In Nonlinear Schrödinger Equations, Tim Van Hoose

Masters Theses

“We study several different problems related to nonlinear Schrödinger equations….

We prove several new results for the first equation: a modified scattering result for both an averaged version of the equation and the full equation, as well as a set of Strichartz estimates and a blowup result for the 3d cubic problem.

We also present an exposition of the classical work of Bourgain on invariant measures for the second equation in the mass-subcritical regime”--Abstract, page iv.

A Convolutional Neural Network (Cnn) For Defect Detection Of Additively Manufactured Parts, Musarrat Farzana Rahman

Masters Theses

“Additive manufacturing (AM) is a layer-by-layer deposition process to fabricate parts with complex geometries. The formation of defects within AM components is a major concern for critical structural and cyclic loading applications. Understanding the mechanisms of defect formation and identifying the defects play an important role in improving the product lifecycle. The convolutional neural network (CNN) has been demonstrated to be an effective deep learning tool for automated detection of defects for both conventional and AM processes. A network with optimized parameters including proper data processing and sampling can improve the performance of the architecture. In this study, for the …

Controlling Microalloy Interactions On Precipitation, Hot Ductility, And Microstructure -- Mechanical Property Relationships, Madhuri Varadarajan

Masters Theses

“One of the main problems faced in the continuous casting of micro-alloy steels is the formation of transverse cracks. Transverse cracks are surface, or near-surface cracks formed perpendicular to the casting direction. The research focuses on using laboratory hot tensile tests methods to determine the low ductility ranges in high strength steel grades with different micro-alloy additions of titanium, niobium, and vanadium. The hot ductility of commercially produced as-cast slab and beam blank samples was evaluated using two experimental methods: tensile testing utilizing a servo-hydraulic load frame with a resistance furnace and thermomechanical testing using rapid Joule heating. The tests …

Validation Of Edna Metabarcoding : A Comparison To Traditional Survey Methods In Ozark Streams, Veronica Marian Lee

Masters Theses

Environmental DNA (eDNA) sampling provides a method for assessing fish communities that has potential as a supplement to traditional sampling methods due to its ability to save time as well as its non-invasive nature. This is a method in which from just one sample, eDNA from multiple individual species are able to be sequenced in tandem and the resulting reads identified to describe a community. In order to evaluate this technique and its efficacy for monitoring fish community diversity, we collected water samples alongside surveys performed by the Missouri Department of Conservation sampling program in summers 2020-21. DNA were extracted …

Pressure Relief Wells: Analysis Of Subsurface Heterogeneity To Evaluate Relief Well Locations For Mississippi River Levees, Emma Marie Young

Masters Theses

“When designing pressure relief well systems, it is imperative to understand what major geomorphology and heterogenies features are present, such as buried oxbow lakes, especially when the feature is parallel to the source, such as the Mississippi River. When present, there is a notable greater increase in head pressures, especially on the landward tow of the levee. This can cause erosional features that originally thought of to have been protected from by installing pressure relief wells. When comparing the effective hydraulic conductivities of horizontal clay layers and vertical clay layers spanning the length of the model, little to no noticeable …

B-Sure (Bereavement Support Research): The Differential Experiences Of Peer And Professional Support In Grief, Andrea Crowley

Theses and Dissertations (Comprehensive)

Abstract

The project aimed to investigate the differential experiences of those who have received peer or professional support for grief and bereavement. Although much is known with regards to the perceived impacts of peer and professional support in general, there is little research surrounding these support types in the context of grief and bereavement, the potential for these support types to be complementary, and how the COVID-19 pandemic may have impacted the experiences of those receiving these forms of support. The main goal of this project was to address a significant gap in the literature by investigating the following questions: …

First Language Loss And Maintenance In Adolescents And Young Adults From Immigrant Backgrounds, Wanxin Li

Theses and Dissertations (Comprehensive)

Abstract

Language attrition is a documented phenomenon that occurs when individuals progressively lose their first language (Schmid et al., 2007). This is particularly common among individuals who relocate to a country that speaks a foreign language that differs from their first language, as the societal language eventually becomes their dominant language. Deterioration and loss of the first language (L1) may result in consequences such as loss of ethnic and cultural identity, leading to the loss of a link to one’s country of origin (Cho & Krashen, 1998). Thus, the present study examined factors that may contribute to L1 attrition. The …

Community Stress And Resilience During Covid-19: Assessing The Emotional Profile Of The City Of Hamilton Using A Social Media Analysis, Senyo Agbeyaka

Theses and Dissertations (Comprehensive)

This study investigated stress and resilience at the neighbourhood level in Hamilton Ontario in pre- and peri-pandemic conditions using a social media analysis. Sentiment analysis of geo-located Twitter posts produced within Hamilton census tract boundaries was conducted using Stresscapes and EMOTIVE, validated software that extract and code emotional information from human language expressions about stress and hope (a proxy for stress), respectively. Baseline levels of both emotions were measured using aggregate scores at the census tract level in Hamilton from tweets produced during two pre-pandemic periods (March 2019 to July 2019; and August 2019 to February 2020), with a replication …

The Hidden Side Of Work-Family Boundary Management: Uncovering The Role Of Cognitive Boundary Work And Boundary Context, Victoria Daniel

Theses and Dissertations (Comprehensive)

Work-family life is becoming increasingly complex for the modern-day working parent, making boundaries that define the physical, temporal, and psychological aspects of work and family domains evermore important in how people choose to structure and manage the interface. However, the literature on boundary management has predominantly studied the enactment of certain boundaries and treated these boundary constructs as stable (e.g., general preferences and tendencies to behaviourally integrate or segment work and family). This research has also largely been conducted in contexts where the environment naturally created a way to organize the interface without the employees having to do as much …

Impact Of Inducing Self-Compassion On The Use Of Safety Behaviours In Social Situations, Kamila Szczyglowski

Theses and Dissertations (Comprehensive)

Safety behaviours are commonly used in an attempt to decrease anxiety experienced in social settings. These behaviours, however, have been found to maintain anxiety. Self-compassion has shown promise for reducing anxiety and post-event rumination. The aim of the present studies was to examine the impact of a self-compassion induction on safety behaviours. It was hypothesized that inducing self-compassion would lead to lower safety behaviour use compared to control conditions. For the first two studies, participants were randomly assigned to complete self-compassion inductions or control writing prompts in relation to imagining a pre-determined social situation. Study 3 followed a similar procedure …

A Grounded Theory Exploration Of The Changing Dynamic In Mission Among Pentecostals In Ontario: The Emergence Of Humanitarianism., Todd Manuel

Theses and Dissertations (Comprehensive)

Abstract

This dissertation explores the changing nature of mission among Pentecostal churches in Ontario. The findings of this grounded theory qualitative research project suggest that mission in those Pentecostal churches in Ontario under review have switched the priority of the juxtaposed foci of salvific and humanitarian such that the latter is now their primary means for expressing mission.

Christianity is a mission-oriented faith tradition. Throughout history, it is the case that the church’s understanding and expression of mission has adjusted and adapted according to the context and culture it has found itself in. In the ever changing religious and cultural …

Fifth-Dimensional Warfare And National Security In Canada: Situating Microdeviation Theory Within C-59: An Act Respecting National Security Matters, Hayden Slight

Theses and Dissertations (Comprehensive)

In an era of rapid technological change, the growing threat environment in the cyber dimension will continue to influence how a sovereign nation contends with attacks that can occur from any corner of the world. The growing adaptation and expansion of technology belonging to the Internet of Things (IoT) and the increasing prevalence of social media (Facebook, Twitter) has also influenced the spreading of attack surfaces that can become victim to exploitation by motivated parties including foreign states and terrorist groups. Against this backdrop, Canada’s own efforts to modernize and reinforce its own national security agencies resulted in the developing …

Exploring Climate, Wellbeing, Resilience, And Resistance In 2slgbtq+ Leisure Spaces: A Mixed Methods Study To Advance Inclusion, Tin Vo

Theses and Dissertations (Comprehensive)

Participating in queer sports groups, rainbow choirs, trans virtual discussion groups and other Two-Spirit, lesbian, gay, bisexual, transgender, queer, and other sexually and gender diverse (2SLGBTQ+) leisure activities can offer participants safety from societal heterosexism and cisgenderism and opportunities for community connection and peer support, as well as foster their overall wellbeing. Yet, transgender/gender nonconforming (TGNC), racialized, and/or disabled individuals, and those with other diverse identities are often marginalized in these spaces. Though researchers have studied exclusion within 2SLGBTQ+ leisure spaces, relatively little is known about how the climate of these spaces shapes social and mental health outcomes. Connected to …

How Narcissism Relates To (Non-) Cooperation, Christopher Chinn

Theses and Dissertations (Comprehensive)

Cooperative behaviour is integral to modern society. Individuals who are high in trait narcissism have personality traits that appear inconsistent with cooperation, such as selfishness, competitiveness, and antagonism. Research has yet to determine whether these individuals, when given the opportunity, are less likely to engage in cooperative behaviour, to the detriment of others. The present studies investigated the effect of several distinct expressions of trait narcissism on cooperation in social dilemmas and potential underlying causes of non-cooperation in narcissistic individuals. In Study 1, participants (N = 355) were randomly assigned to one of three prisoner’s dilemma conditions (control, low …

The Kepler Problem On Complex And Pseudo-Riemannian Manifolds, Michael R. Astwood

Theses and Dissertations (Comprehensive)

The motion of objects in the sky has captured the attention of scientists and mathematicians since classical times. The problem of determining their motion has been dubbed the Kepler problem, and has since been generalized into an abstract problem of dynamical systems. In particular, the question of whether a classical system produces closed and bounded orbits is of importance even to modern mathematical physics, since these systems can often be analysed by hand. The aforementioned question was originally studied by Bertrand in the context of celestial mechanics, and is therefore referred to as the Bertrand problem. We investigate the qualitative …