Engineering Commons^™

Improvements Of Atmospheric Deposition Sampling Procedures And Further Analysis Of Its Impact On Utah Lake, Seth Michael Barrus

Theses and Dissertations

This study focused on Atmospheric Deposition (AD) loading on Utah Lake. Utah Lake is susceptible to Harmful Algal Blooms (HABs) because of its large surface area to volume ratio, proximity to Great Basin dust sources, and various wind patterns from close mountain ranges that blow AD towards the lake. In this study, we continued the collection and analysis of AD samples that started in 2017 and 2018, while reporting additional 2019 and 2020 data. We constructed a sampler on Utah Lake itself, which allowed us to better estimate how AD loads were distributed over the lake. An interpolation assumption was …

Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Sttenio Alcantara

Theses and Dissertations

The purpose of this research is to develop best practices for deploying air quality sensors in a remote location such as Mongolia. I discussed the architecture and design constraints when collecting remote air quality sensors data, the challenges that emerge while implementing a sensor-based network in a remote location such as Mongolia. The tradeoffs of using different architectures are described. I observed the usage of electrical heaters in modified gers in remote locations and conclude how effective they are in reducing PM2.5 levels by analyzing air quality data and go through the process of cleaning up the data and removing …

Geoglows Hydroviewer: Open Software-As-A-Service For Localizing Global Hydrologic Forecasts Of The Group On Earth Observations Global Water Sustainability Initiative, Kyler Ralph Ashby

Theses and Dissertations

Earth observation data is increasingly ubiquitous, easily accessible, freely available, and generally usable due to improvements in software, data standards, network infrastructure, and national policies. As a result, greater opportunities arise for using these data in a wider field of application including decision support for local and regional environmental and water resources management efforts. In parts of the world where in situ data are less readily available, global Earth observation data used in such decision support tools can be a boon to underfunded government and private water management agencies. The United Nations Group on Earth Observations Global Water Sustainability initiative …

Preferential Vaporization Potential Of Crude Oils And Its Impact On Flame Flashback Behaviors, Ayuob Al Wahaibi

Theses and Dissertations

As combined cycle gas turbines for power generation operating on light distillate fuels provide a sufficient energy, there is a global trend in using heavy liquids (e.g. HFO, crude oils) for direct-firing in gas turbine. However, using these heavy fuels imposes many challenges due to their wide range of physical/chemical properties, which control near-limit combustion behaviors, such lean blow-out and flashback. In addition, the ignition propensity of these heavy fuels is not reported in crude assays, and utilizing a simple, with small sample, and quick methodology to characterize the ignition propensity is important in determining the fuel quality.

In this …

Optimizing Cost And Performance Of Infrastrucure Alternatives At Contingency Bases In A Hub-And-Spoke Network, Kyle J. Rodriguez

Theses and Dissertations

Military contingency bases require substantial resources and funding sustain and are often not connected to an infrastructure grid. Infrastructure assets produce the required outputs for sustainment, but are often expensive and inefficient, producing a significant logistical burden. With the increasing near-peer threats of opposing military forces, there is a need for more self-sufficient contingency bases with alternatives that reduce resources usage and the cost of sustainment. Accordingly, the goal of this research is to develop an optimization model capable of selecting infrastructure alternative combinations that minimize the overall resource usage and cost of sustainment at the contingency base level.

Gps-Denied Localization Of Daughter-Ships In A Mother-Daughter Ship Collaborative Environment, Ethan W. Jacquin

Theses and Dissertations

This research investigates the possibility of using the communication link between a mothership and daughter-ship UAV and an Extended Kalman Filter algorithm as a replacement of GPS, assuming a ranging link exists between the mothership and daughter-ship and that the mothership is GPS-enabled. A simulation study examines the viability of the approach and the effect of parameters such as distance, altitude, roll angle, speed, ranging sensor noise, and inertial measurement unit uncertainty were considered. The magnitude of the errors between predicted and measured position were examined and a range of acceptable flight parameters was formed.

Stochastic Programming Design For West Africa Logistics Networks, Julius C. Walker

Theses and Dissertations

The USAFRICOM is studying methods to increase the resiliency of its West African Logistic Network, a hub-and-spoke network design responsible for sustaining long term humanitarian and security missions in the West Africa region. This paper employs a two-stage stochastic programming network design modeled on the WALN that builds a flexible supply chain capable of responding to periodic disruptions while maintaining peak resiliency. Elements such as cost, probability, and event-based disruption are integrated into the model to mirror challenges the WALN faces. We demonstrate that incorporating resilient based response mechanism provide a 90% reduction in cost compared to meeting the logistical …

Evaluating The Impact Of Culture On Customer Satisfaction For Fms Projects, Yaquari A. Adams Ii

Theses and Dissertations

The cost, time, and quality pillars of the iron triangle in project management are often considered the most important factors for managers to consider when striving to achieve project success. However, recent literature suggests customer satisfaction and end-user benefit are the most important elements to prioritize during project development. This research analyzes the Air Force Security Assistance Center Construction Division and Foreign Military Sales (FMS) joint construction operations in relation to two Project Management Body of Knowledge (PMBOK) knowledge areas, project stakeholder management and project risk management. Project stakeholder management is addressed by identifying the relationship between cultural competency and …

Experimental And Modeling Of Biomass Char Gasification, Ruochen Wu

Theses and Dissertations

This investigation provides a comprehensive experimental dataset and kinetic model for biomass gasification, over a wide temperature range (1150-1350 °Ï¹) in CO2, H2O and the combination of these two reactant gases over the mole fraction ranges of 0 to 0.5 for H2O and 0 to 0.9 for CO2. The data come from a unique experimental facility that tracks continuous mass loss rates for poplar wood, corn stover and switchgrass over the size range of 6-12.5 mm. In addition, the data include char size, shape, surface and internal temperature and discrete measurements of porosity, total surface area, pore size distribution and …

Signal Transport And Rf Over Fiber Design For Alpaca, Erich Johannes Nygaard

Theses and Dissertations

The design of the RF over fiber signal transport system for the ALPACA receiver is described, with particular attention to the strict noise requirements as well as dynamic range considerations. Also discussed are analytical tools for analyzing dynamic range in the context of RFI-rich radio astronomy observational settings, including formulas for maximum interference to noise ratios and a simulation framework for predicting distortion levels. Phase and gain stability measurements of the signal transport system are presented, including the effects of the multi-strand armored fiber optic cable. The resulting system meets design requirements, with equivalent noise temperature below 900 K in …

Evaluating The Stabilization Of Gypseous And Gypsiferous Sands Using Different Chemical Additives To Mitigate Gypsum Dissolution, Mohammed Kamil Faris

Theses and Dissertations

Gypsum, which is dihydrate calcium sulfate, (CaSO4.2H2O), is widely available in different sizes, from the size of a rock to the size of a few micrometers as a mineral, in different types of soils. It is primarily found mainly in arid and semi-arid areas around the world at different depths. Soils with gypsum and even gypsum rocks are very hard in their dry state. However, these soils and rock will experience remarkable dissolution upon wetting.

The dissolution phenomenon, which takes place in soils that contain gypsum, creates different geotechnical problems within the soil’s profile, along with foundation issues for structures …

Aligning Performance Management Systems For Lasting Outcomes In Humanitarian Operations, Kalyn M. Howard

Theses and Dissertations

Logistics is dynamic, expansive, and critical to organizational success. While it is generally believed that effective logistics management is associated with positive performance outcomes, the links between organizational practice and performance are understudied. This dissertation leverages resource-based theory and organizational learning theory to examine organizational practice and performance in non-traditional logistics settings, with particular focus on military organizations and humanitarian operational settings. First, a meta-analytical study establishes generalizable associations between various operations management practices and performance outcomes. Then, this is applied to dynamic humanitarian logistics settings, exploring how practitioners perceive practice and performance, and how this is reported and documented …

Assessing The Effects Of Reconstruction On The Commercial And Civil Construction Industry Following Hurricane Maria In Puerto Rico, Timothy Jafek Barrett-Rodriguez

Theses and Dissertations

In September 2017 Hurricane Maria made landfall on the U.S territory island of Puerto Rico, causing substantial damage to the already weakened infrastructure and other aspects of the built environment. This research attempted to identify the challenges and opportunities that have been encountered within the Puerto Rican commercial and civil construction industry during the first year of reconstruction, post-Hurricane Maria. This was done by identifying the effects of the storm as well as the strategies of construction companies involved in the reconstruction process. The study used the events occurring after the passing of the hurricane as a case study to …

17 Β-Estradiol And Phytoestrogens Attenuate Apoptotic Cell Death In Hiv-1 Tat Exposed Primary Cortical Cultures, Sheila Marie Adams

Theses and Dissertations

Despite the advent of highly active antiretroviral therapy (HAART), neurological disorders develop in most people infected with human immunodeficiency virus type 1 (HIV-1). The poor CNS delivery of anti-retrovirals allows continued virus production and renders neurons susceptible to the toxic effects of released viral proteins. The neurotoxic potential of HIV-1 viral protein Tat has been shown to include excitotoxicity, oxidative stress, and mitochondrial dysfunction leading to subsequent cell death. Thus, Tat is thought to have a key role in the pathogenesis of HIV-associated neurodegeneration. Estrogens are universally considered to be neuroprotective, as such; estrogens have positive implications in the treatment …

Evaluating The Impacts Of Hurricane Maria On The Residential Construction Industry In Puerto Rico And The Effectiveness Of Reconstruction Efforts, M. Bradley Wells

Theses and Dissertations

In September of 2017, Hurricane Irma and Hurricane Maria, both category 5 hurricanes, swept across the Caribbean, including the U.S. Territory island of Puerto Rico. These two storms, particularly Hurricane Maria, caused catastrophic damages from high winds and flooding to the island paradise. This research investigates the direct effects that Hurricane Maria had on the residential construction industry within Puerto Rico and evaluates how to better prioritize and manage these types of efforts in the future. This research was initiated to identify challenges and opportunities that have been encountered within the Puerto Rican construction industry during the first year of …

Identifying High-Potential Work Areas In Engineering For Global Development: Linking Industry Sectors To The Human Development Index, Daniel Oliver Smith

Theses and Dissertations

Those working in Engineering for Global Development seek to improve the conditions in developing countries. A common metric for understanding the development state of a given country is the Human Development Index (HDI), which focuses on three dimensions: health, education, and income. An engineer’s expertise does not always align with any of those dimensions directly, while they still hope to perform impactful work for human development. To discover other areas of expertise that are highly associated with the HDI, correlations and variable selection were performed between all World Development Indicators and the HDI. The resultant associations are presented according to …

Evaluation Of The Cytotoxic Effect Of Salvia Triloba On Osteosarcoma (U2os) Cell Line, Rowan Bahaa El-Din Abd El-Bary

Theses and Dissertations

Despite the huge advancement in the field of cancer treatment, the conventionally used treatments still present significant challenges such as low effectiveness and adverse side effects. Thus, there is a critical need to continuously develop new, more effective and safe drugs against cancer. Herbal plants serve as a potential source for a wide variety of complex compounds with probable anticancer activity. The genus Salvia encompasses about 900 species. Salvia triloba, commonly known as Greek sage, is native to the Middle East and is inherently linked to local traditional medicine systems. It was recently shown to possess anti-proliferative activity against breast …

Development Of Plane Rotating Traction System: Based On The High-Speed Rail (72+128+72) M Continuous Prestressed Concrete Beam Bridge, Weinan Wang

Theses and Dissertations

With the advent of rotate construction techniques, it is easy to build a new bridge crossing over existing structures, rivers and valleys quickly, easily and safely. Although the general concept of the rotating method is similar for different engineering characteristics, it is necessary to make some changes, which are more in line with the requirements of the particular project. Based on a 3-spans (72+128+72)m continuous concrete bridge, this paper presents a new rotation method, the down-slide-way unbalanced rotation system, which can save time and reduce cost compared to the up-slide-way rotation method. Through the improvements of the traction system and …

On The Characterization Of Natural Language Structure And Literary Stylometry - A Network Science Approach, Younis Anas Younis Al Rozz

Theses and Dissertations

Natural language processing (NLP) techniques have been through many advancements in recent years, linguistics and scientist utilized these techniques to solve many challenges related to written language and literary. Problems such as finding the genetic relationships among languages, attributing author of a text and categorizing text by genre have been treated throughout the years using conventional statistical methods, for instance, bag of words (BoW), N-gram, the frequency of words and the lexical distance between words. By considering written language as a complex system, network science tools and techniques can be used to address those problems. A unified methodology is proposed …

The Evolution Of The Southeastern North American Margin From Integrated Analyses Of Potential Field Data: Continent-Continent Collision And Rifting, Patrick D. Duff

Theses and Dissertations

The southeastern North American margin (SENAM) is one of the world’s oldest intact passive margins, containing the ancient southern Appalachian Mountains, the South Georgia Rift (SGR), and the Central Atlantic Magmatic Province (CAMP).

Potential field data is used in combination with seismic imaging, borehole data, and surface geology to better constrain the lithospheric configuration created by Appalachian orogenesis and Atlantic rifting. In combination with filtering techniques, maps and 2D potential field forward models, and Euler inverse modeling are used to illuminate the pre-Cretaceous basement including basement faults, shear zones, and granites in the hinterland of the southern Appalachians, and rift …

Geophysical Study Of Gold Mineralized Zones In The Carolina Terrane Of South Carolina, Saad Saud Alarifi

Theses and Dissertations

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he goal of this study was to calibrate and test geophysical methods for the detection of geological structural and disseminated sulfides in the area of the four largest gold deposits in the Southern Appalachian of South Carolina. The Coastal plain sediments, vegetation and saprolite covering the mining areas remain the most challenging in this region. The work focused on the calibration of high-resolution gravity, and helicopter electromagnetic (EM) and magnetic data provided by OceanaGold over the Haile and Brewer Mines; then calibrating the regional gravity and aeromagnetic data over the four gold mines in South Carolina. Observed geophysical fields …

Helicobacter’S Effects On Colitis/Colon Cancer And The Response To Indole 3-Carbinol, Rasha Raheem Abdulhamza Alkarkoushi

Theses and Dissertations

Enterohepatic Helicobacter (EHH) species are gram-negative bacteria, which are poorly studied. Several studies suggest that EHH species contribute to inflammatory bowel disease IBD in humans. IBD and colorectal cancer (CRC) has emerged as a public health challenge worldwide. Indole-3-carbinol (I3C) is one of the natural dietary indoles abundant in Brassica (cruciferous) vegetables. The aryl hydrocarbon receptor (AhR) plays an essential role as a regulator by controlling the balance between Tregs and Th17 cells. The activation of AhR by ligands derived from food or intestinal microbiota is an essential control mechanism in that balance. Moreover, many studies showed indoles achieving chemo-preventive …

Advancing The Accessibility, Reusability, And Interoperability Of Environmental Modeling Workflows Through Web Services, Xiaohui Qiao

Theses and Dissertations

Global flood forecasting can benefit developing countries and ungauged regions that lack observational data, computational infrastructure, and human capacity for streamflow modeling. Many technical challenges exist to provide flood predictions on a global scale. First, existing land surface forecasts use coarse resolution grid cells, which provide limited information when used for flood forecasting at local scales. There is, so far, no modeling system that can provide rapid and accurate global flood predictions with low cost. Second, accurate flood predictions often require integrating interdisciplinary models, data sources, and analysis routines into a workflow. Limited accessibility, reusability, and interoperability of models restrict …

Spacecraft Position Estimation And Attitude Determination Using Terrestrial Illumination Matching, Liberty M. Shockley

Theses and Dissertations

An algorithm to conduct spacecraft position estimation and attitude determination via terrestrial illumination matching (TIM) is presented consisting of a novel method that uses terrestrial lights as a surrogate for star fields. Although star sensors represent a highly accurate means of attitude determination with considerable spaceflight heritage, with Global Positioning System (GPS) providing position, TIM provides a potentially viable alternative in the event of star sensor or GPS malfunction or performance degradation. The research defines a catalog of terrestrial light constellations, which are then implemented within the TIM algorithm for position acquisition of a generic spacecraft bus. With the algorithm …

The Effect Of Aeration Rate And Free-Floating Carrier Media On The Emission Of Bacillus Globigii In Bioaerosols, Andrew J. Owens

Theses and Dissertations

Aerosols produced by turbulent mechanical mixing and bubble aeration at Waste Water Treatment Plants (WWTPs) become bioaerosols with the entrainment of biological materials. Bioaerosols become a public health risk when human pathogens are present. This study evaluated bioaerosols containing Bacillus globigii (BG) spores, and the effects that aeration rate and the addition of Free-Floating Carrier Media (FFCM) had on the amount of BG spores collected following aerosolization. A series of laboratory-scale experiments investigated two different sizes of floating polystyrene spheres as FFCM and four different aeration rates. When the differences in compared aeration rates were sufficiently large, a positive correlation …

A Machine Learning Approach To Characterizing Particle Morphology In Nuclear Forensics, Daniel A. Gum

Theses and Dissertations

A machine learning approach is taken to characterizing a group of synthetic uranium bearing particles. SEM images of these lab-created particles were converted into a binary representation that captured morphological features in accordance with a guide established by Los Alamos National Laboratory. Each particle in the dataset contains an association with chemical creation conditions: processing method, precipitation temperature and pH, calcination temperature are most closely tied to particle morphology. Additionally, trained classifiers are able to relate final products between particles, implying that morphological features are shared between particles with similar composition.

Preferred Treatment Methods For Patients With Inflammatory Bowel Disease, James L. Deitschel

Theses and Dissertations

Shared decision making is the concept of physicians involving patients in the treatment planning process. The University of Maryland Medical Center is interested in applying shared decision making to the treatment of patients with Inflammatory Bowel Disease (IBD). The two treatment methods analyzed in this study were medical management and surgery. To explore patient preferences between these two alternatives, a discrete choice experiment (DCE) was employed. The responses for the DCE were binary, so logistic regression models were explored. The conditional logistic regression model was determined to be the most appropriate for this analysis. After step-wise regression was performed, a …

Novel Planar Wire-Grid Antenna Arrays For Automotive Radars Operating At 77 Ghz, Hossam Helaly

Theses and Dissertations

Automotive radars are the critical components for future driving assistance technologies. Nowadays, their usage is a constraint on the premium segment automobiles; however, there are intensive studies to facilitate these technologies to the lower segment. The main challenges that face automakers to develop new automotive radars are fabrication cost, compactness, bandwidth, and radiation properties. This research focuses on developing a novel class of planar antenna arrays, which operate at a frequency of 77 GHz. The proposed arrays can be fabricated using multilayered cheap printed circuit board lamination technology. The proposed antennas are arrayed using mixed wire-gridding and corporate arraying techniques, …

Beneficiation Of Coal Using Supercritical Water And Carbon Dioxide Extraction, Matthew Decuir Virginia Commonwealth University Cl

Theses and Dissertations

This work explores the use of carbon dioxide, water, and their mixtures as solvent for the pre-combustion beneficiation of raw coal without using any toxic mineral acids in the temperature range of 200-400℃. The fluid polarity, ionic constant, and supercritical point can be adjusted by H₂O/CO₂ ratio and temperature. Adding carbon dioxide to hydrothermal fluid also increases the ionization by forming carbonic acid. Extractions with supercritical fluids have several benefits including enhanced mass transport, ease of separation and recycle, wide range of extractive capability and tunability, better inherent safety, and in the case of carbon dioxide and …

Using Nano- And Micro- Structural Materials For Concrete Environmental Applications, Hala Nabeel Elia

Theses and Dissertations

Utilized globally in the construction industry, concrete is an integral component of homes, roads, airports, skyscrapers, and tunnels. Traditional concrete components are cement, fine aggregate (sand), coarse aggregate (gravel or crushed stone), and water. When cement and water compound together they will make a paste which binds all the aggregates together to make the concrete. Unfortunately, every one ton of cement manufactured emits 0.9 ton of CO2into the air. The goal of this two-part work was to obtain an environmentally friendly concrete. The first part used supplementary cementitious materials (SCM), fly ash and silica fume, to create concrete with high …