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Performance Evaluation Of A Triple Concentric Tube Heat Exchanger Using Deionized Water And Oil-40, Huda Majid Hasen

Baghdad Science Journal

This study examines experimentally the performance of a horizontal triple concentric tube heat exchanger TCTHE made of copper metal using water as cooling fluid and oil-40 as hot fluid. Hot fluid enters the inner annular tube of the TCTHE in a direction at a temperature of 50, 60 and 70 oC and a flow rate of 20 l/hr. On the other hand, the cooling fluid enters the inner tube and the outer annular tube in the reverse direction (counter current flow) at a temperature of 25 oC and flow rates of 10, 15, 20, 25, 30 and 35 l/hr. The …

Developing Firmware For Space Weather Probes 2 Using Hdl Coder, Nicholas L. Wallace

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

GPS and wireless communications are affected by interference from the ionosphere. Space weather affects plasma in the ionosphere, causing communication disruptions and reliability issues. To better understand how space weather affects the ionosphere, instruments are flown in space to collect data about the electrical characteristics of plasma in the ionosphere. Space systems require a lot of time and effort to develop and test. This thesis explores how a high level tool can be used to simplify the process and some obstacles that still exist with developing some space systems. To do this, the firmware architecture of a new version of …

Consumption Of A Western Diet Enhanced Colitis-Associated Colorectal Cancer And Dysbiosis Of The Fecal Microbiome In Mice Notwithstanding Dietary Intervention Or Fecal Microbiome Transfer, Daphne Michelle Rodriguez Jimenez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In a rodent model of inflammation-associated colorectal cancer, consumption of a Western-style diet increases gut inflammation and enhances risk of developing colon tumors. The goal of this dissertation was to understand the contribution of bacteria within the large intestine on colon inflammation and colon tumorigenesis. Two pre-clinical animal studies were performed using two different intervention strategies to shift the microbiome, and potentially gut inflammation and tumor development: 1) an experiment using dietary supplementation with black raspberries, a functional food enriched in bioactive anthocyanins with purported antiinflammatory activity, and 2) an experiment using fecal microbiota transfer from mice fed a healthy …

A Cohesive Simulation And Testing Platform For Civil Autonomous Aerial Sensing And Operations, Stockton G. Slack

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Drones (also known as sUAS or small Uncrewed Aerial Systems) are often flown with cameras to take images of an area of land. These images can then be used to create a map by stitching these images together. This map can then be analyzed using scientific principles to learn things about the land and make decisions or take action based on the information.

The scientific application of drones is very advantageous, but flying a drone is inherently dangerous, impacting the safety of the airspace (particularly in the event of a crash), and drones are more dangerous the bigger they are. …

Cislunar Navigation Techniques And Navigation Performance Optimization, Quinn P. Moon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nova-C is a lunar lander developed by the private company Intuitive Machines to deliver commercial payloads to the Moon. The IM-1 mission set for 2023 will launch and land the Nova-C near the Moon's south pole. In this research, various navigation techniques are explored to determine the lander's position and velocity during key segments. This process is studied for key mission events including trajectory correction maneuvers (TCMs), lunar orbit insertion (LOI), and descent orbit insertion (DOI). Each mission segment, referred to as an Orbit Determination Segment (OD), is analyzed with three different navigation techniques: Monte Carlo Analysis, Linear Covariance Analysis, …

Precipitation And Soil Properties Determine Long-Term Consequences Of Disturbance And Invasion In Drylands, Tyson Terry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Disturbance and invasive species have dramatic effects on desert plant communities, often resulting in degradation or shifts to alternative plant communities. Climate and soil properties determine water availability to plants, and have been thought to drive patterns of recovery following disturbance and potential for invasion.

In chapter II we used a combination of natural gas pipelines and satellite imagery to understand how recovery from a uniform disturbance differs across precipitation and soil gradients. We used a recovery ratio (disturbed/undisturbed) of pipeline pixels and their undisturbed nearest neighbor pixel to quantify recovery in a comparable way across precipitation gradients. We found …

A Mechanistic Examination Of Interspecific Competition Between Wild And Domestic Herbivores, Courtney Check

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large herbivores, such as mule deer and cattle have similar life histories and likely compete for resources. However, quantifying the extent to which these species compete and the specific resources they compete for has proved challenging. My research examines if cattle influence deer abundance and behavior due to competition for forage, competition for shade, and/or by affecting the predation risk of deer. Using a grid of autonomous trail cameras, I was able to determine if cattle abundance influences local deer abundance in relation to specific resources and habitat features. Using GPS data from collared deer, I was also able to …

Preservice Teacher Engineering Design Teaching Efficacy, Laura Wheeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Science educators are tasked with enacting The Next Generation Science Standards that include engineering core ideas and practices. Many teacher preparation programs and content courses do not include or require engineering design leading many science teachers to believe they are unprepared to teach engineering design. The lack of experience and belief of being unprepared to teach engineering design results in preservice educators’ lack of engineering design teaching self-efficacy. Preparation programs inclusion of efficacy in is essential to understanding later enactment. This mixed-method case study researched the engineering design teaching self-efficacy of eleven preservice educators during an engineering design unit taught …

From Flames To Forage: How Wildfire Affects Elk Behavior And Abundance, Megan M. Whetzel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Rocky Mountain elk (Cervus elaphus nelsoni) is an ecologically and culturally important wildlife species in the Intermountain West, but it is facing habitat changes caused by increasing fire activity. Wildfire frequency is projected to continue to change into the future, yet increases in annual area burned and increases in area burned at high severity may actually represent opportunities for some species. Large herbivores like elk may benefit from increased access to regenerating areas where forage abundance and quality are often elevated. Therefore, effective management of wildlife populations may depend on quantifying how large ungulates, like elk, alter …

The Intersections Of Payments For Ecosystem Services, Gender, And Conditionality In A Bolivian Case Study, Alicia Potter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Payments for Ecosystem Services (PES) have gained traction since the 1990s and are designed to provide cash or in-kind incentives to natural resource managers who alter land management behavior to protect ecosystem services. Conservation programs generally are known to interact with household and community gender dynamics. For other types of cash transfers, recent literature has noted that presence of conditionality (a key aspect of PES) may create or reinforce gender inequalities, which often manifest in household divisions of labor and decision-making where women may be obligated to complete more unpaid work or experience less control over resources.

Based on a …

App-Based Academic Interventions For Children With Autism, Cassity R. Haverkamp

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Technology, such as tablet/phone apps, robots, video games, and virtual reality, can be used to teach skills to autistic children. Research on technology supports for autistic youth often focus on social skills, a main part of an autism diagnosis. However, autistic children may also have academic challenges, and fewer studies have looked at how technology can teach academic skills to children with autism. We created three studies to look at how academic apps may benefit autistic children. In the first study, we reviewed studies that looked at how academic apps can increase the academic skills of children with autism. We …

Laboratory Measurements At The Impact Point Of A Falling Jet, Garrett Richins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dams and spillways play a vital role in managing water resources. Many of these hydraulic structures feature a falling jet when discharging downstream. Engineers design plunge pools to receive jets with enough water depth or a protective liner to protect the river bottom so that scour is avoided. Quantifying the pressures at the bottom of the falling jet is a key component to determining the potential for scour and the need for mitigation techniques.

In the laboratory setting, significant discrepancies have been observed between different measurement methods to measure mean and fluctuating pressures of a falling jet intercepting a solid …

Mission Planning Techniques For Cooperative Leo Spacecraft Constellations, Skylar A. Cox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research develops a mission planning approach that allows different systems to cooperate in accomplishing a single mission goal. Using the techniques described allows satellites to cooperate in efficiently maneuvering, or collecting images of Earth and transmitting the collected data to users on the ground. The individual resources onboard each satellite, like fuel, memory capacity and pointing agility, are used in a manner that ensures the goals and objectives of the mission are realized in a feasible way. A mission plan can be generated for each satellite within the cooperating group that collectively optimize the mission objectives from a global …

Generalizing Deep Learning Methods For Particle Tracing Using Transfer Learning, Shubham Gupta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Particle tracing is a very important method for scientific visualization of vector fields, but it is computationally expensive. Deep learning can be used to speed up particle tracing, but existing deep learning models are domain-specific. In this work, we present a methodology to generalize the use of deep learning for particle tracing using transfer learning. We demonstrate the performance of our approach through a series of experimental studies that address the most common simulation design scenarios: varying time span, Reynolds number, and problem geometry. The results show that our methodology can be effectively used to generalize and accelerate the training …

Diversity In Tech: Analyzing The Mismatch Between Corporate Framing And Impact, Rana Abulbasal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This doctoral dissertation investigates the discrepancy between tech companies' substantial investments in diversity programs and the persistently low representation of Black, Indigenous, and people of color (BIPOC) employees. Despite extensive efforts, discrimination and harassment against women and people of color persist in the industry. The study employs a critical interdisciplinary approach, comprising sociological perspectives on diversity management and two empirical studies. The first scrutinizes tech companies' framing strategies of diversity initiatives on their websites, while the second explores the impact of Diversity, Equity, and Inclusion (DEI) policies on women of color in the industry. By identifying shortcomings and proposing recommendations, …

Durability Of Wireless Charging Systems Embedded Into Concrete Pavements For Electric Vehicles, Pilaiwan Vaikasi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The interest in electric vehicles (EVs) has been growing around the world significantly. EVs run on electricity by charging power to their batteries. However, a concern in the operation of the EVs is raised because they have an insufficient battery charge to reach their destination. In-motion, inductive power transfer (IPT) embedded into the roadway for the EVs can ease the need to use a charging stationary. This project focused on the durability of the dynamic charging IPT electronics integrated into concrete pavements. This research collaborated with electrical and mechanical engineering colleagues from the Advancing Sustainability through Powered Infrastructure for Roadway …

Mird Pamphlet No 28, Part 2: Comparative Evaluation Of Mirdcalc Dosimetry Software Across A Compendium Of Diagnostic Radiopharmaceuticals, Daniel Lafontaine

Faculty, Staff and Student Publications

Radiopharmaceutical dosimetry is usually estimated via organ-level MIRD schema-style formalisms, which form the computational basis for commonly used clinical and research dosimetry software. Recently, MIRDcalc internal dosimetry software was developed to provide a freely available organ-level dosimetry solution that incorporates up-to-date models of human anatomy, addresses uncertainty in radiopharmaceutical biokinetics and patient organ masses, and offers a 1-screen user interface as well as quality assurance tools. The present work describes the validation of MIRDcalc and, secondarily, provides a compendium of radiopharmaceutical dose coefficients obtained with MIRDcalc. Biokinetic data for about 70 currently and historically used radiopharmaceuticals were obtained from the …

Dissemination Of Class A Cephalosporinases And Class D Carbapenemases In Escherichia Coli Isolates From A Tertiary Hospital In Sudan

Faculty, Staff and Student Publications

Introduction

The high prevalence of urinary tract infections (UTIs) and rising resistance to beta-lactam antibiotics, which is a global therapeutic concern, are caused by Escherichia coli (E. coli) extended-spectrum beta-lactamases (ESBLs) producers. It is unclear how E. coli that produces ESBLs spreads throughout Gezira state, Sudan. The study aimed to evaluate the dissemination of class A and class D resistance genes among E. coli and to recognize the antibacterial activity of the locally used cephalosporins and carbapenems.

Methods

One hundred and fifteen isolates of uropathogenic E. coli were collected from patients who attended a tertiary hospital. The isolates …

Kokkos-Enhanced Exampi, Evan Drake Suggs

Masters Theses and Doctoral Dissertations

Kokkos provides in-memory advanced data structures, concurrency, and algorithm to support advanced C++ parallel programming. MPI provides the most widely used message passing model for inter-node communication. Many programmers use both Kokkos and the Message Passing Interface (MPI) together. In this thesis, Kokkos is integrated within an MPI implementation to obtain performance and functionality benefits both for the MPI itself, and for applications that use both Kokkos+MPI. For instance, it will be possible in this model to pass first-class Kokkos objects directly to extended C++-based MPI APIs. In particular, efforts to achieve this type of integrated model is expressed using …

City Of Devils, Preston Trammell

Masters Theses and Doctoral Dissertations

This thesis contains two parts: a craft paper on merging fantasy and mystery genres and the first fifty pages of an adult fantasy mystery novel. The craft paper explores different strategies authors use to navigate the tension between mystery and the supernatural, and it analyzes these strategies in three novels, Storm Front by Jim Butcher, Ninth House by Leigh Bardugo, and The 7 ½ Deaths of Evelynn Hardcastle by Stuart Turton, all of which are mystery-fantasy novels involving the supernatural. The novel pages in the thesis are from City of Devils, which follows Kassandra Thorpe, a private investigator who receives …

A Study Of Higher Education Alumni Perceptions Of In-Person Or Online Engagement, Jacquelyn T. Johnson

Masters Theses and Doctoral Dissertations

The purpose of this study is to investigate the preferred methods of communication and alumni engagement of higher education institution alumni donors in an era with increased social media and electronic communications. During and after the COVID-19 pandemic, Alumni Relations Offices (AROs) were challenged with a changing world environment and new ways in which people were interacting with each other and especially their alma maters. Through a quantitative formatted questionnaire and qualitative focus groups, a Stratified Alumni Engagement Model is suggested to create a varied engagement approach for AROs.   This research is based upon the social exchange theory, the theory …

Effect Of Heat Treatment On The Mechanical And Corrosion Properties Of The Cocrnifeal Heas, Ahmed Korra

Masters Theses and Doctoral Dissertations

High entropy alloys (HEAs) are a relatively new class of metallic materials that have shown great potential for use in extreme environments, such as high temperatures and corrosive conditions. Among the different types of HEAs, CoCrNiFeAl HEAs are potential materials for a wide range of applications, including aerospace, biomedical, and energy storage. This work focused on the effects of heat treatment temperatures from 800 °C to 1100 °C on the microstructure and mechanical properties of these alloys, as well as their electrochemical corrosion behavior. A thermodynamic model was implemented to predict the performance of the material. The results of this …

The Impact Of Interdepartmental Psychological Safety On Interdepartmental Conflict Management Styles, Ryan Limpus

Masters Theses and Doctoral Dissertations

Conflict is an inevitable part of life, and organizations spend a sizable amount of time addressing it. Literature has shown a connection between conflict management styles and psychological safety, but little research has been afforded to these interactions applied across departments. Data were collected from various companies across the United States using an anonymous survey to quantify respondents’ perceived level of general psychological safety, interdepartmental psychological safety, and preferred styles of conflict management. The results of this study indicated that a significant difference between interdepartmental and general psychological safety exists and is positively correlated with each other. Furthermore, certain styles …

Developing A Predictive Geospatial Habitat Model For A Rare Species Of Salamander In Tennessee: A Case Study For The Green Salamander (Aneides Aeneus), Erin Gaylord

Masters Theses and Doctoral Dissertations

Green Salamanders (Aneides aeneus; Cope and Packard 1881) are a secretive and cryptic species of salamander that can be relatively difficult to detect, due to their occupation of arboreal habitats. The incorporation of geospatial tools is critical in developing models that can be used to predict undocumented locations in Tennessee and elsewhere. Locating the species in Tennessee was accomplished through a total of 18 localities and with that, several habitat characteristics were able to be identified including, but not limited to: appropriately shaded and structured rocks, typical fauna co-occurring within the area, and general topography of the area. Of the …

Analyzing The Labor Shortage In The Construction Industry And The Best Practices To Increase Worker Satisfaction, Cade Batchman

Construction Management

The construction industry is facing a significant labor shortage, which has far-reaching implications for the industry and the economy. This paper explores the causes of the shortage and the practices being implemented to address it. Economic changes, technological advancements, union/open shop dynamics, educational shifts, and the industry's image all contribute to the shortage. The economic rebound from the 1980s recession and the lack of new entrants into the field have created a demand-supply gap. Additionally, slow adoption of technology and the perception of construction work as physically demanding and risky have deterred potential workers. The decline in union membership has …

Predicting Dynamic Fragmentation Characteristics From High-Impact Energy Events Utilizing Terrestrial Static Arena Test Data And Machine Learning, Katharine Larsen, Riccardo Bevilacqua, Omkar S. Mulekar, Elisabetta L. Jerome, Thomas J. Hatch-Aguilar

Student Works

To continue space operations with the increasing space debris, accurate characterization of fragment fly-out properties from hypervelocity impacts is essential. However, with limited realistic experimentation and the need for data, available static arena test data, collected utilizing a novel stereoscopic imaging technique, is the primary dataset for this paper. This research leverages machine learning methodologies to predict fragmentation characteristics using combined data from this imaging technique and simulations, produced considering dynamic impact conditions. Gaussian mixture models (GMMs), fit via expectation maximization (EM), are used to model fragment track intersections on a defined surface of intersection. After modeling the fragment distributions, …

Fiber-Based Seismic Damage And Collapse Assessment Of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Indices, Yu-Fu Ko, Jessica Gonzalez

Mineta Transportation Institute

Near-fault earthquakes can have major effects on transportation systems due to the structural damage they impose on bridges. Therefore, it is imperative to assess the seismic damage of bridges appropriately, and this research focuses on reinforced concrete (RC) bridges. This research advances the seismic performance assessment of RC single-column pier-supported bridges with flexural failure under near-fault ground motion by use of ductility coefficients and damage indices. The methodology included modeling fiber-based nonlinear beam-column elements to simulate the damage development process of RC bridge piers under earthquake loadings, considering the global buckling of longitudinal steel bars, examining the cracking and spalling …

System-Of-Systems Integration For Civil Infrastructures Resiliency Toward Multihazard Events, Vahid Balali

Mineta Transportation Institute

Civil infrastructure systems—facilities that supply principal services, such as electricity, water, transportation, etc., to a community—are the backbone of modern society. These systems are frequently subject to multi-hazard events, such as earthquakes. The poor resiliency of these infrastructures results in many human casualties and significant economic losses every year. An outline of a holistic view that considers how different civil infrastructure systems operate independently and how they interact and communicate with each other is required to have a resilient infrastructure system. More specifically a systems engineering approach is required to enable infrastructure to remain resilient in the case of extreme …

Community Space Planning And Design Guide For Enhanced Wildfire Resilience In Heber, Utah, Devin Macfarlane

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The wildland urban interface (WUI) is the fastest growing land type in the conterminous United States. These areas are prone to catastrophic wildfire events. In response to rapid population growth, Heber City, Utah is planning a significant amount of development within the WUI. This thesis project is aimed at proactively addressing wildfire risk in the WUI of Heber through two main strategies: regional geospatial planning and public space design to create wildfire resilient communities. Researching principles of wildfire adaptive practice and planning for defensible space led to the development of a list of criteria. This list was developed in the …

Growth And Emergent Functionalities Of Oxide Thin Films Utilizing Interface Engineering, Detian Yang

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

Complex oxide interfaces have offered intriguing novel emergent phenomena and multiple functionalities through interfacial reconstructions of spin, orbital, charge, and lattice degrees of freedom. Interface engineering via manipulating interfacial interaction, defects and multiple interfacial quantum charges and orders constitutes the essential method and technique to achieve desired functionalities in oxide heterostructures. In this thesis, shown are two examples of utilizing interfacial reconstruction and interfacial strain engineering to achieve intrinsic exchange bias and realize epitaxial growth of mixed-valence hexagonal manganite thin films, respectively.

Firstly, we demonstrated intrinsic exchange bias induced by interfacial reconstruction in Ni_xCo_yFe_3-x-yO …