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Characterization Of Landfill Leachate For Enhanced Metal Recovery, Hanna Fulford, Amisha Shah, Inez Hua, Nadezhda Zyaykina, Lori Hoagland, Alejandro Rodriguez Sanchez, Umut Bicim

Discovery Undergraduate Interdisciplinary Research Internship

Landfills contain a trove of valuable materials, such as critical, precious, and rare earth metals, that are integral to the United State’s economy and national security. The leachate that filters through landfills picks up these materials, which allows for the possibility of recovery. For this research, samples will be analyzed from landfills throughout the Midwestern United States to provide a baseline on water quality constituents, elements present, and microbial activity. Preliminary data for this study was acquired by analyzing samples of landfill leachate from a landfill in northern Indiana. pH readings indicate that the leachate is slightly basic. It also …

Using Facies Analysis And Reservoir Characterization Of The Albian-Cenomanian Nanushuk Formation To Assist In Better Understanding Interactions Between Shoreface, Deltaic, And Fluvial Systems On The North Slope, Alaska, Andrea Smoot

Theses and Dissertations

The Albian-Cenomanian Nanushuk Formation located on the North Slope of Alaska is the result of fluvial, deltaic, and shoreface processes and has been the focus of recent petroleum exploration activity in the Colville Basin. The Nanushuk and underlying Torok formations together contain an estimated 8.7 billion barrels of oil and 25 trillion cubic feet of natural gas reserves within the resource-rich North Slope. The Nanushuk Formation is composed of sediment sourced from the Chukotka Peninsula to the west and deposited axially within the Colville Basin. High sedimentation rates led to rapid progradation of shoreface and deltaic systems, which effectively filled …

Falling Through The Cracks Of Education: A Comparative Analysis Of Canada’S And The United States’ Use Of Standardized Testing Within The Realm Of Public Education, Micaela Baldner

University of Miami International and Comparative Law Review

The education system is foundational to society. Public education is based on the concept of equal educational opportunities for all. Although the purpose of standardized testing is the elimination of bias to prevent certain segments of society’s students from receiving unfair academic advantages, there is little empirical verification that suggests that standardized testing actually achieves its intended purpose. In fact, the evidence indicates that standardized testing negatively impacts low-income, marginalized, and English-learning students, as achievement gaps for these groups have remained the same or have even grown with the increased use of such tests. This article will discuss the intended …

Winter Commencement: December 16-17, 2021, University Of North Dakota

UND Commencement Programs

UND Winter Commencement program from December 16 and 17, 2021.

State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr

Doctoral Dissertations and Master's Theses

Today, the exploration and exploitation of space continues to become a more common occurrence. All types of spacecraft (S/C) utilize various types of thermal management solutions to mitigate the effects of thermal loading from the unforgiving vacuum of space. Without an appropriately designed thermal system, components on-board the S/C can experience failure or malfunction due to fluctuations in temperatures either beyond the designed operational parameters or unstable oscillating temperatures. The purpose of this study is to perform a comprehensive review of technologies available today that are being used for thermal management onboard S/C in addition to investigating the means to …

Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah

Doctoral Dissertations and Master's Theses

Cryogenic sprays have many applications in modern engineering. Cooling of electronic equipment subject to high heat flows, surgical ablation of gastrointestinal mucosae or orbital maneuvering are a few examples of their versatility. However, the atomization of a cryogenic liquid is a complex process. During such an event, aerodynamic effects associated with secondary atomization are further affected by thermodynamic flashing. A better understanding of the characteristics of cryogenic sprays is then necessary to allow for improved design and optimization in applications. The overarching objective of this study is to document such characteristics. The numerical simulation was performed over cryogenic nitrogen spray …

Paleoindian Response To Climate Change In The Northern Jornada Del Muerto, Christopher Wayne Merriman

Anthropology ETDs

Human-environment interaction is a long-standing and productive line of inquiry that includes the study of cultural responses to climate change. However, demonstrating a causal relationship between climate change and the consequent culture change is rarely straightforward for numerous reasons. In this dissertation I develop an optimality model to predict how Paleoindians should have responded to changes in precipitation across the Late Pleistocene-Early Holocene. The water supply model (WSM) ranks water supplies much like the diet breadth model ranks food resources. To adjust the WSM for climate change, paleoclimate records from playas in the northern Jornada del Muerto were used in …

Predicting Stocks With Lstm-Based Drnn And Gan, Duy Ngo

Master's Projects

Trading equities can be very lucrative for some and a gamble for others. Professional traders and retail traders are constantly amassing information to be a step ahead of the market to profit off the value of stocks on the market. Some of the tools in their arsenal include different types of calculations based on a variety of data collected on a stock. Technical analysis is a technique for traders to analyze the data of equities presented on charts. Often, the way the price changes over time can be used as an indicator for traders to predict how future prices will …

The Effect Of Virtual Labs On High School Student Attitudes Towards Chemistry, Emily Koehler

Dissertations, Theses, and Projects

This mixed-methods action research project evaluated high school chemistry student attitudes towards chemistry before and after the students completed a virtual laboratory. Students were surveyed by utilizing the Attitude Toward the Subject of Chemistry Inventory (Bauer, 2008) and a random sample of students were interviewed by the author. Survey scores in five subscales (emotional satisfaction, anxiety, intellectual accessibility, interest and utility, and fear) were compared through statistical analysis of mean, standard deviation, and t-test. Student attitudes were not significantly different before and after the virtual laboratory experience but did show a general decrease in perceptions of interest and utility of …

Positive Influences On Why They Stay: A Qualitative Study On The Contributing Factors To Teacher Retention In Rural North Dakota, Jennifer A. Jung

Dissertations, Theses, and Projects

An alarming number of educators are leaving the field within the first five years of employment. Midwestern rural schools experience a slightly higher percentage of turnover than do their urban counterparts. Due to this shortage of teachers, many districts across the nation have employed strategies to recruit and retain competent teachers. This qualitative study employs a phenomenological approach seeking to identify common themes among teachers who are long-staying teachers in a rural district (those with 1000 or fewer students). Both the social constructivism and teacher career cycle theoretical frameworks have been utilized to support the researcher’s understanding of rural teachers' …

The Effects Of Activity-Based And Inquiry-Based Teaching Methods On Student Attitude And Perception Toward Geometry, Wade Hukriede

Dissertations, Theses, and Projects

This quantitative action research project evaluated high school students’ attitude and perceptions toward geometry before and after two units that were taught. The first unit was taught using a more traditional style of teaching while the second method incorporated activity-based and inquiry-based lessons into a traditional method of teaching. The students were surveyed by using a modified version of Bauer’s (2008) Attitude Toward the Subject of Chemistry Inventory. The survey was changed to focus on the students’ attitudes and perceptions toward geometry. Survey scores in the subscales: interest and utility, anxiety, intellectual accessibility, fear and emotional satisfaction were compared through …

Electric Vehicle Integration In San Francisco, Lisa Farmos

Master's Projects and Capstones

California’s Executive Order N-79-20 requires all new cars and passenger trucks sold in California to be zero-emissions by 2035. Electric vehicles (EVs) are the primary alternative fuel solution. However, there are widespread barriers to ownership, particularly for those in lower socioeconomic classes. A literature review of barriers to EV ownership shows the primary barrier is insufficient overnight charging infrastructure. Geospatial data of EV charging infrastructure and 2020 census tract data were used to map average income versus EV charging infrastructure in San Francisco. Data maps confirm the literature review findings: there is a positive correlation between income and EV charging …

Salt Marshes As Groundwater Buffers For Development: A Survey Of South Carolina Salt Marsh Basins, Alicia M. Wilson, Meghan Shanahan, Erik M. Smith

Faculty Publications

Salt marshes serve as zones of intense groundwater mixing and reaction between freshwater uplands and estuaries. This raises the question of whether the impacts of upland development on nutrient and carbon species can be transmitted through salt marshes via groundwater, or whether salt marshes can buffer estuarine waters from coastal development. We sampled groundwater from fifteen tidal creek basins in South Carolina to test for compositional differences associated with development and marsh width. Groundwater samples from near creekbanks and below freshwater uplands were analyzed for salinity, total dissolved nitrogen and phosphorus, and dissolved organic carbon. Analyses revealed significantly higher TDN …

An Open Source Direct Messaging And Enhanced Recommendation System For Yioop, Aniruddha Dinesh Mallya

Master's Projects

Recommendation systems and direct messaging systems are two popular components of web portals. A recommendation system is an information filtering system that seeks to predict the "rating" or "preference" a user would give to an item and a direct messaging system allows private communication between users of any platform. Yioop, is an open source, PHP search engine and web portal that can be configured to allow users to create discussion groups, blogs, wikis etc.

In this project, we expanded on Yioop’s group system so that every user now has a personal group. Personal groups were then used to add user …

Intracavity Phase Interferometry Based Fiber Sensors, Luke Jameson Horstman

Optical Science and Engineering ETDs

Intracavity Phase Interferometry (IPI) is a detection technique that exploits the inherent sensitivity of a laser's frequency to the parameters of its cavity. Intracavity interferometry is orders of magnitude more sensitive than its extracavity alternatives. This dissertation improves on previous free-space proof-of-concept designs. By implementing the technique in fiber optics, using optical parametric oscillation, and investigating non-Hermitian quantum mechanics and dispersion tailoring enhancement techniques, IPI has become more applicable and sensitive. Ring and linear IPI configurations were realized in this work, both operating as bidirectional fiber optical parametric oscillators. The benefit of using externally pumped synchronous optical parametric oscillation is …

Robotic Olfactory-Based Navigation With Mobile Robots, Lingxiao Wang

Doctoral Dissertations and Master's Theses

Robotic odor source localization (OSL) is a technology that enables mobile robots or autonomous vehicles to find an odor source in unknown environments. It has been viewed as challenging due to the turbulent nature of airflows and the resulting odor plume characteristics. The key to correctly finding an odor source is designing an effective olfactory-based navigation algorithm, which guides the robot to detect emitted odor plumes as cues in finding the source. This dissertation proposes three kinds of olfactory-based navigation methods to improve search efficiency while maintaining a low computational cost, incorporating different machine learning and artificial intelligence methods.

A. …

Synthetic Aperture Optical Imaging Interferometric Microscopy With Improved Image Quality, Preyom K. Dey

Electrical and Computer Engineering ETDs

The resolution limit of optical microscopy can be extended by using Imaging Interferometric Microscopy (IIM), which uses a low numerical aperture (NA) objective lens to achieve resolution equivalent to that of a high-NA objective lens with multiple sub-images. Along with the resolution enhancement challenge, IIM often suffers from poor image quality. In this dissertation, several image quality improvement methods are proposed and verified with simulation and experimental results. Next, techniques to extend the resolution limit of IIM to ≤ 100nm using a low-NA objective lens are demonstrated. An experimental technique of using a grating coupler on …

Flax/Acrylic Flow Turbine Blade Manufactured By In Situ Polymerisation (Isp) Monomer Infusion Under Flexible Tooling (Mift), Y Qin, R Cullen, John Summerscales, Jasper Graham-Jones, Maozhou Meng, Richard Pemberton

School of Engineering, Computing and Mathematics

A flax fabric reinforced acrylic thermoplastic matrix component has been manufactured as two half blades (front and back respectively) with the parts bonded together with a wood dust acrylic polymer to produce a component with the same thermoplastic polymer used for the composite matrix and the adhesive. The mould profile is for a floating offshore wind (FLOW) turbine blade at scale 1:50. This model represents the NREL 5 MW reference wind turbine. The blades are not scaled geometrically, but instead have been adapted to produce Froude scaled thrust, in spite of much lower Reynolds numbers at reduced scale and when …

Solvation Of Isoelectronic Halide And Alkali Metal Ions By Argon Atoms, Carly A. Rock, Sarah N. Arradondo, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work systematically examines the interactions of alkali metal cations and their isoelectronic halide counterparts with up to six solvating Ar atoms (M+Arn and X–Arn, where M = Li, Na, K, and Rb; X = H, F, Cl, and Br; and n = 1–6) via full geometry optimizations with the MP2 method and robust, correlation-consistent quadruple-ζ (QZ) basis sets. 116 unique M+Arn and X–Arn stationary points have been characterized on the MP2/QZ potential energy surface. To the best of our knowledge, approximately two dozen of these stationary points have been reported here for the first time. Some of these new …

Correlating Sentiment In Reddit’S Wallstreetbets With The Stock Market Using Machine Learning Techniques, Sultan Ali Alzaabi

Theses

The issue that this study addresses is to observe whether there exists a statistical relation between the stock market and Reddit’s wallstreetbets. Previous research mainly focused on the relation between the stock market and Twitter. To gather data for the study, comments were scrapped from the subreddit wallstreetbets for a period of four months, Jan 1, 2021, till April 30, 2021. Different sentiment classifiers were, then, applied on a sample of the data to observe the most accurate classifier for the study. The study concluded that the most accurate sentiment classifier was an SVM classifier trained on 80% of Reddit …

Ecological Exposure And Effects Of Microplastics In Crabs Along The Pacific Coast, Dorothy A. Horn

Dissertations and Theses

Microplastics have been documented across the global oceans as an ubiquitous pollutant. Found in the water column, sediment, shorelines, estuaries, freshwater streams and rivers along with terrestrial soils, flora and fauna. The continuous input of plastic waste into the marine environment doesn't seem to be slowing as the amount of plastic created each year increases globally.

This study investigated (1) the effects of microplastic ingestion in the indicator species, the Pacific mole crab (Emerita analoga), testing the predator avoidance behavior, reproductive output and parasitism effects when an adult female gravid crab had ingested microplastics (2) adult mortality, hatching …

Management Of Meadow Fescue Pasture For High-Producing Dairy Cows In Northern Japan, K. Sudo, K. Ochiai, T. Ikeda

IGC Proceedings (1977-2023)

The objective of this study was to establish an intensive grazing system of meadow fescue (Festuca elatior L.) pasture for high-producing dairy cows in some areas of Japan where soil freezes in winter. Plant succession of meadow fescue pastures that had been grazed at different plant heights and milk production from cows grazed on meadow fescue pasture compared to that from cows grazed on perennial ryegrass pasture were surveyed over a five year period. Succession of meadow fescue pasture depended on the management of plant height before grazing use. Milk production from cows grazed on meadow fescue pasture was …

Leaf Blade Selection By Sheep In Kleingrass (Panicum Coloratum L.) Pastures With Different Deferment Periods, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1977-2023)

The winter use of standing dead biomass produced by warm season grasses during the previous growing season may be an alternative to grazing systems in the semi-arid Pampean Region of Argentina. This study evaluated: 1) the effect of different deferment periods on the leaf blade percentage and quality of ‘kleingrass’ (Panicum coloratum L.), a warm season specie recently introduced to that region, and 2) whether rams grazing the vegetation accumulated during these different periods are able to select leaf blades to maintain the quality of their diets. It was generated three treatments by deferment of the forage produced after …

Microhistological Estimation Of Leaf Blade Percentage In Diets From Monoespecific Pastures, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1977-2023)

Although a decrease in the leaf-stem ratio affects the nutritive value of pastures, herbivores can reinforce selection for leaf blades to maintain the quality of their diets. This study evaluated whether the percentage of fragments with furrows in blades could be used to estimate the relative intake of this part of the leaves by herbivores grazing monoespecific pastures. It was worked with vegetation of kleingrass (Panicum coloratum L.) from paddocks with three deferment periods. Blade samples, and different plant part mixtures hand compounded were in vitro digested. The digestion residues were microhistological analyzed determining the number of fragment with …

Evaluation Of Kentucky Bluegrass (Poa Pratensis L.) For Creating Sustainable Grazing Swards In Hokkaido, T. Saigusa, S. Tejima, Y. Ogawa, S. Takahashi

IGC Proceedings (1977-2023)

Kentucky bluegrass (Poa pratensis L.) is generally considered to be a weed in the meadows of Hokkaido. However, a revaluation of this species should be undertaken in terms of its useful characteristics for labor-saving management on farms in marginal areas. The performance of steers (Holstein-Friesian) and botanical composition of Kentucky bluegrass swards were investigated under the stocking methods of set and rotational grazing and compared with timothy (Phleum pratense L.) swards. Kentucky bluegrass was stable over the grazing season under both methods, although timothy decreased rapidly. The average daily gain of steers raised on Kentucky bluegrass swards was …

The Pow+Tree Strategy’S Effects On The Argumentative Writing Of Struggling Secondary Students, Matthias Grünke

Journal of Educational Research and Practice

The present study aims to evaluate the effects of an argumentative writing strategy (POW+TREE) on four struggling ninth graders’ ability to produce persuasive texts regarding their point of view on different questions. I applied a multiple-baseline design to evaluate outcomes across participants. The results indicate the intervention helped students to write more extensive essays, and evidence shows an increase in quality. Follow-up data suggest the effects remained after the treatment ended. I also discuss future research and the findings’ implications for practitioners.

Accuracy Of Routine 2d Echocardiography To Estimate Pda Type And Dimension And Predict Device Selection For Successful Pda Occlusion, Mohammed Omar Galal, Zaheer Ahmed, Arif Hussain, Masroor Sharfi, Yahia El Mahdi, Fayzah El Khattab, Amjad Alkouatli, Riad Abou Zahr

Journal of the Saudi Heart Association

Background: Assessment of the shape and dimensions of PDA is usually done angiographically and in the majority of cases need arterial access. Our aim was to evaluate the value of routine 2 D echocardiography (ECHO) in predicting type, dimensions of PDA and to anticipate device size to be used during the intervention. Material and Methods: The charts of all patients who underwent transcatheter closure of PDA between January 2015 and December 2020 were reviewed. Their pre-procedure ECHO and catheterization details at the time of device closure were analyzed. Results: Total of 139 patients were reviewed and 8 were excluded because …

The Effect Of A Financial Crisis On Household Finances: A Case Study Of Iceland’S Financial Crisis, Axel Hall, Andri S. Scheving, Gylfi Zoega

Journal of Financial Crises

Iceland experienced a financial crisis in 2008–2009 when its banking system collapsed, the currency lost half its value, most businesses became technically insolvent, house prices fell, and household debt increased due to indexation to foreign currencies or the price level. This paper tells the story of the crisis and maps the losses to households using a dataset from tax returns that includes all taxpayers in the country and contains the value of housing, mortgage debt, disposable income, and net worth. For relative losses in net worth, the results show that families with children, especially those with parents aged between 24 …

Elementary Teachers’ Verbal Support Of Engineering Integration In An Interdisciplinary Project, Sarah Lilly, Anne M. Mcalister, Jennifer L. Chiu

Journal of Pre-College Engineering Education Research (J-PEER)

Despite emphasis on authentic science, technology, engineering, mathematics, and computer science (STEM+CS) projects in classrooms, research continues to demonstrate opportunity gaps in learning STEM+CS for students with disabilities. This study investigates how teachers verbally support students in two differently tracked classrooms to engage in engineering lessons that integrate science and computer science. Specifically, this study explores how the same elementary teachers both implicitly and explicitly support students across two classroom contexts, one class section with a larger proportion of students who were tracked into accelerated mathematics and another class section with a larger proportion of students with individualized educational plans …

Modeling Deception: A Case Study Of Email Phishing, Abdullah Almoqbil, Brian C. O'Connor, Richard Anderson, Jibril Shittu, Patrick Mcleod

Proceedings from the Document Academy

Information manipulation for deception continues to evolve at a remarkable rate. Artificial intelligence has greatly reduced the burden of combing through documents for evidence of manipulation; but it has also enabled the development of clever modes of deception.

In this study, we modeled deception attacks by examining phishing emails that successfully evaded detection by the Microsoft 365 filtering system. The sample population selected for this study was the University of North Texas students, faculty, staff, alumni and retirees who maintain their university email accounts. The model explains why certain individuals and organizations are selected as targets, and identifies potential counter …