Digital Commons Network^™

Applications Of Micro-X-Ray Fluorescence (Μxrf) Techniques To Ore Formation Questions In Economic Geology, Hannah Adwoa Buamono

Open Access Theses & Dissertations

Advances in x-ray optics over the past decade have enabled a new generation of benchtop micro energy-dispersive x-ray fluorescence (µXRF/EDS) instruments to analyze samples with an x-ray spot size of 25 microns or less and detection limits of tens to hundreds of parts per million. The analysis of samples from mineral (ore) deposits may illustrate some of the capabilities and limitations of these instruments applied to geoscience problems. The qualitative elemental analysis process allows the production of detailed elemental maps which, together with line scan profiles and other petrographic and geochemical evidence, leads to a better definition of key chemical, …

Identifying Particulate Matter Spatial Variation In The El Paso Del Norte Region Using Land-Use Regression Modeling And Data Obtained From A Network Of Low-Cost Sensors, Leonardo Demetrio Vazquez-Raygoza

Open Access Theses & Dissertations

The emergence and rise in popularity of low-cost sensors for atmospheric observation aresetting a new precedent in identifying emission hotspots and providing high-resolution spatial and temporal data. Furthermore, low-cost sensors are becoming popular among institutions and the public, allowing community scientists to become more involved in air quality monitoring. However, concerns about the accuracy and precision of low-cost sensors have been questioned. Most recent research has focused on the utility of real-time monitoring and calibration requirements for these sensors. A low-cost monitoring project has deployed sensors in the El Paso del Norte region in low and high annual average daily …

Curiosity-Driven And Victim-Aware Adversarial Policies, Chen Gong, Zhou Yang, Yunpeng Bai, Jieke Shi, Arunesh Sinha, Bowen Xu, David Lo, Xinwen Hou, Guoliang Fan

Research Collection School Of Computing and Information Systems

Recent years have witnessed great potential in applying Deep Reinforcement Learning (DRL) in various challenging applications, such as autonomous driving, nuclear fusion control, complex game playing, etc. However, recently researchers have revealed that deep reinforcement learning models are vulnerable to adversarial attacks: malicious attackers can train adversarial policies to tamper with the observations of a well-trained victim agent, the latter of which fails dramatically when faced with such an attack. Understanding and improving the adversarial robustness of deep reinforcement learning is of great importance in enhancing the quality and reliability of a wide range of DRL-enabled systems. In this paper, …

Implementation Of Empath X Sla Predictive Tool For A Government Agency, Hui Shan Lee, Shankararaman, Venky, Eng Lieh Ouh

Research Collection School Of Computing and Information Systems

Service Level Agreement (SLA) plays a significant role in the relationship between citizens and the government. It stipulates the quality levels required for the meaningful interaction between the two parties. Most SLA predictive models consider end-to-end duration and frequency of failed service requests as model inputs with little research on the analysis of textual details of the service request. This is an issue for government bodies as the latter do not just want to meet SLA, but also be proactive by knowing the citizens before assisting them. Inclusion of textual data potentially answer to this requirement of knowing the citizen …

Understanding Sentiment Through Context, Richard M.Crowley, M.H. Franco Wong

Research Collection School Of Accountancy

We examine whether empirical results using text-based sentiment of U.S. annual reports depend on the underlying context, within documents, from which sentiment is measured. We construct a clause-level measure of context, showing that sentiment is driven by many different contexts and that positive and negative sentiment are driven by different contexts. We then construct context-level sentiment measures and examine whether sentiment works as expected at the context-level across four prediction problems. Our results demonstrate that document-level sentiment exhibits significant noise in prediction and suggest that document-level aggregation of sentiment leads to missed empirical nuances. The contexts driving sentiment results vary …

An Ethnohistorical Exploration Of Educational Technology Implementation In Metropolitan Omaha Area Public Schools: One Leadership Perspective, Linda M. Ward

Educational Leadership Theses, Dissertations, and Student Creative Activity

An Ethnohistorical Exploration of Educational Technology Implementation in Metropolitan Omaha Area Public Schools is a written account of the evolution of 1:1 program in five public school districts. These metropolitan Omaha area districts share their journey in developing programs that provide equity in accessing educational technology to all students. An annotated history of educational technology and the International Society for Technology in Education (ISTE) standards and their effect on education and educators is also addressed.

Implementing A Reference Backscatter Calibration Technique On A Multi-Sector Multibeam Echosounder, Rui Miguel Aleixo Miguel Cândido

Master's Theses and Capstones

Increasingly, national hydrographic agencies are committing to routine acquisition of seabed backscatter strength estimates from multibeam echosounders (MBES) as part of national programs for seabed characterization. As part of their bathymetric survey mandate, these agencies have a long history of sounding quality control utilizing absolute and relative calibration (reference surfaces and crossover comparisons). Equivalent quality control is, however, not yet in place for managing seabed backscatter strength measurements, as the majority of the collected data is not absolutely referenced.Herein, a new technique for cross-calibrating a MBES with a reference calibrated split beam echosounder (SBES) was implemented. Broadband reference bottom backscatter …

The Effect Of The 2018 Tariffs On European Wine, Henry Johnson

Boise State University Theses and Dissertations

This paper estimates a vector autoregression model for average wine prices across U.S. cities to assess the impact of tariff changes on the U.K., France, Germany, and Spain after they were enacted in October 2019. It uses impulse response functions to gauge how a one-unit impulse in the per-liter duty rate may effect the average wine price in the U.S. and the quantity of wine from various exporters to the U.S. It finds that a one-unit impulse in the duty rate levied against the bloc of countries impacted by the tariff results in a fall in the quantity of wine …

Accessible And Inclusive Online Course Design In Higher Education, Amy Lomellini

Boise State University Theses and Dissertations

The growth of online learning has expanded the reach of higher education to more diverse students than ever before; however, students often face barriers to equitable access to online instructional materials, course activities, and assessments. The challenge of meeting the needs of diverse learners was both highlighted and exacerbated during the COVID-19 pandemic and the rapid shift to remote teaching and learning at many institutions. Disabled students were one group that was particularly affected. Research has explored faculty and students’ (with and without disabilities) perceptions of online learning; however, less is known about instructional designers’ and their team leaders’ roles …

The U.S. Endangered Species Act And Agency Discretion: The Role Of Public Commenting During The Rulemaking Process, Krista Helmstadter Lyons

Boise State University Theses and Dissertations

The most recent International Union for Conservation of Nature (IUCN) Red List classifies 40,084 out of the 142,577 evaluated species as threatened with extinction, with 1,962 of those species identified in the United States. The U.S. Endangered Species Act (ESA) was enacted in 1973 to protect and recover threatened and endangered species from extinction. The ESA federal listing process can be lengthy and arduous, taking years for a species to be proposed for listing. During the process the U.S. Fish and Wildlife Service (FWS) seeks comments from the public and peer reviewers on the proposed rule. Previous research debates the …

Understanding Students' Experience With 1:1 Computer-Supported Collaborative Learning In A Mathematics Classroom, Oscar Antonio Perales Aguilera

Boise State University Theses and Dissertations

There has been a move towards integrating educational technology into K-12 mathematics classrooms. This emphasis has been partly driven by policy, increases in technology resources available, and a need to engage students in their mathematical learning. Most studies on technology integration in mathematics education are focused on teachers’ perceptions or students’ academic achievement. However, we need to learn how students perceive their learning in this type of environment. This dissertation is a basic qualitative study aimed at understanding the experiences of students with 1:1 computer-supported collaborative learning (CSCL) in an Algebraic Reasoning classroom. The study used the mathematical software, Desmos, …

Game-Based Learning: Examining Factors That Influence K-12 Classroom Usage, Sean Ward

Boise State University Theses and Dissertations

Video games have become a popular and accepted part of digital culture and are becoming more accepted as an engaging instructional tool in schools. Integration of games can help develop students’ intrinsic motivation for learning and are a great way for teachers to incorporate student interests and make connections to the curriculum. Classroom usage of digital games is becoming more widespread, but prior research suggests that game-based learning is underutilized as a tool in the teacher toolbox. This study seeks to understand the factors that influence teachers’ decisions to use or not use digital games in their classroom and make …

An Elementary School Principal’S Practices And A Reduced Equity Gap: A Case Study, April Hrovat

Dissertations

During the last 60 years, national standardized testing has confirmed a gap in reading and math scores between White and Black students, often called the achievement, opportunity, equity, or race-based gap (Coleman et al., 1966; NCES, 2021). Researchers have attempted to identify factors that influence these student outcomes (Jayavant, 2016). Leithwood et al. (2004) found that the practices and behaviors of building leaders "are second only to classroom instruction in school-related factors that contribute to what students learn at school" (p. 5). Based on their significant impact, research has been conducted to identify effective social justice and mainstream educational leadership …

Investigating 9-1-1 Call Experience For Medical Emergencies For Future Design, Leanna Machado

Honors College Theses

Emergency calling services have continued to use the 9-1-1 phone number to share information about a medical emergency for around 60 years. However, there are limitations to the current emergency call services that can have improved communication, speed, and accuracy with the implementation of advancing technology. By examining the experience and opinions of 9-1-1 medical emergency callers, we are able to investigate the design of 9-1-1 services to enhance the call experience. The major challenges found in the study are difficulty in verbally explaining the emergency situation and difficulty in describing the location of the emergency. Technologies such as location …

Mgrre_Thinsections_Mgrre-129_6, Mgrre

Thin Sections

No abstract provided.

Mgrre_Thinsections_Mgrre-129_2, Mgrre

Thin Sections

No abstract provided.

Analysis Of Forensic Artifacts In Database Memory Using Support Vector Machine, Mahfuzul I. Nissan

LSU New Orleans Theses and Dissertations

Memory analysis allows forensic investigators to establish a more complete timeline of system activity using a snapshot of main memory (i.e., RAM). Investigators may rely on such analysis to detect malicious activity and understand the scope of what data was exfiltrated. This is of particular interest in the presence of incomplete or untrusted logs, where a privileged user (or an attacker with such capabilities) can altogether bypass or disable logging. In such instances, a forensic investigator can still rely on the fact that data must ultimately be processed in memory, regardless of the information that is recorded in audit logs. …

Photoproducts And Transformations Of Organic Pollutants In Aquatic Environments, Elizabeth Whisenhant

LSU New Orleans Theses and Dissertations

The degradation of petroleum-derived organic pollutants in aquatic systems occurs through lengthened exposure to UV and visible light. In this thesis, organic pollutants include crude oil, refined fuels, and plastic particles or films. The photo-oxidation of these pollutants are monitored over natural waters. To characterize the molecular signatures of photo-oxidized petroleum, bench-scale spills of refined fuels and crude oil were irradiated over Alaskan waters. A 4-component fluorescence PARAFAC model revealed a unique feature associated with photo-oxidized refined fuel unlike traditional “microbial”- or “terrestrial-like” components. In contrast, crude oil photolytically decomposed into humic-like components and oxidized aliphatics. FT-ICR MS data corroborated …

Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide as a working fluid in a closed Brayton cycle is proving to be more efficient than a conventional steam-based Rankine engine. Understanding the heat transfer properties of supercritical fluids is important for the design of a working engine cycle. The thermophysical properties of supercritical fluids tend to vary non-linearly near the pseudo-critical region. Traditionally, empirical correlations are used to calculate the heat transfer coefficient. It has been shown in the literature and within our own studies that these correlations provide inaccurate predictions near the pseudo-critical line, where heat transfer may be deteriorated or enhanced, resulting from strong …

Ultra-Long-Haul Commercial Operations: An Assessment Of Current Health And Safety Standards, Aditya Rathi

Doctoral Dissertations and Master's Theses

The international and national authorities, manufacturers, and commercial airlines have invested extensively in-flight crew operational research and aircraft system development in preparation for ULH flights. Conversely, the progress on health and safety and its impact and standards has received limited attention in the industry. Though stringent medical certification requirements by international and national regulatory bodies ensure no deviance in operational safety, less emphasis has been put on other occupational factors that can impact the aircrew while operating these ULH routes.

The current studies on the topic are sparse and have only focused on factors such as fatigue, sleep loss, circadian …

The Living Breakwaters Pdr Efforts Econcrete Resource Analysis, Guianina Ferrari, Shervon Stephens, Calvin O. Walters Jr.

Publications and Research

On October 29, 2012, Superstorm Sandy impacted 443,000 people and caused nearly $19 billion (about $58 per person in the US) worth of damage within New York City. As part of the New York City infrastructure reparation plan, the Living Breakwaters project in Tottenville addressed coastal resilience, allocating $100M of public funds to a series of artificial breakwaters by the southwest coast of Staten Island. Each breakwater is constructed and designed to mitigate water flow in storm events. ECOncrete, a primary element of the breakwater, is a specialty cast cementitious product that is marine organism-friendly that encourages biocalcification and photosynthesis. …

Computer Ethics In Curriculum, Tiya Williams

Publications and Research

Ethics specifically in Computer Curriculum is a growing problem that has yet to be widely addressed. Although, start of computer ethics being taught has been traced back to the early 1940’s it has not been standardized or implemented in all computer curriculum. The objective of this research is to diagnose the reasons why ethics is so crucial in computer curriculum at all levels. I used surveys to investigate whether students were taught ethics in their computer curriculum. I also conducted surveys for professors at universities and colleges if they were taught ethics while obtaining their degree, as well as if …

Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The fatalities, injuries, and property damage that result from traffic crashes impose a significant burden on society. Current research and practice in traffic safety rely on analysis of quantitative data from crash reports to understand crash severity contributors and develop countermeasures. Despite advances from this effort, quantitative crash data suffers from drawbacks, such as the limited ability to capture all the information relevant to the crashes and the potential errors introduced during data collection. Crash narratives can help address these limitations, as they contain detailed descriptions of the context and sequence of events of the crash. However, the unstructured nature …

Trace Element Behaviors During Igneous Evolution And Hydrothermal Alteration Of An Evolved Rhyolite, The Blawn Formation, Wah Wah Mountains, Utah: Implications For Critical Metal Abundances In Highly Evolved Rhyolites, Drew William Barkoff

UNLV Theses, Dissertations, Professional Papers, and Capstones

A-type rhyolites and granites often contain elevated concentrations of the rare earth elements (REE) and many other critical trace elements relative to I- and S-type rhyolites and granites. Their trace element-enriched nature makes them potentially prospective bulk tonnage, low-grade resources of the REE and many other critical trace elements, including Li, Be, Mo, Sn, and W, but little work has been performed to delineate their economic potential. The 22.1 Ma Red Beryl Rhyolite (RBR) and the 18.3 Ma Tetons Rhyolite (TR) units of the Blawn Formation represent two A-type rhyolite domes located in the southern Wah Wah Mountains of Utah. …

Application Of Experimentally Calibrated Numerical Models For Prediction Of Composite Masonry Prism Strength, James Bristow

UNLV Theses, Dissertations, Professional Papers, and Capstones

The composite masonry prism test is a common laboratory test to determine the compressive strength of a set of masonry prisms (f’mt) to verify that the composite masonry prism assembly, and more importantly, the constituent materials, are providing adequate strength. While constructing masonry structures, the subcontractors, designers, and inspectors rarely provide continuous supervision or inspection of the construction process. Accordingly, verification of grout mix design, mixed proportions, proper installation of blocks, placement of mortar, dimensions of joints, etc. are more traditionally performed on a periodic basis instead. However, through the use and review of the composite masonry prism test results, …

Age And Genesis Of W-Mo-Cu Mineralization, Gold Hill, Utah, Nathan J. Carey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Utah's Gold Hill mining district hosts a Jurassic felsic pluton (~80 km^2) that was emplaced into a Mississippian to Pennsylvanian carbonate-dominated sedimentary sequence and is spatially associated with numerous polymetallic mineral deposits. This study focuses on W-Mo-Cu mineralization at the Lucy L., Doctor, Yellow Hammer, Reaper, and Rustler deposits within the district. The new, detailed petrographic observations, mineral chemistry (on scheelite, molybdenite, chalcopyrite, magnetite, garnet, and pyroxene), and Re-Os molybdenite geochronological data presented here allows for the determination of key mineral associations and paragenesis, the characterization of deposit types and their evolution, and the constraining of the relative and absolute …

A Mechanically Intelligent Hosing-Drone, Blake Hament

UNLV Theses, Dissertations, Professional Papers, and Capstones

This manuscript presents a ”mechanically intelligent” approach to designing a Hosing-Drone for heavy-duty pressure washing. Spraying a hose creates strong reaction forces and torques. Previously demonstrated spraying robots are over-engineered to be very massive with huge inertias. These high inertias ”wash out” the reaction from the spraying. In the proposed approach, the contributions from all observable fluid dynamics, fluid structure interactions, and aerodynamics are studied individually and for the coupled system. Experimental data is collected and fit to dynamic models. These models are used to design a smaller, lighter, more agile vehicle than has been previously demonstrated. An impedance controller …

Hydrogeologic Heterogeneity Identification: Using Inverse Modeling Of Synthetic Borehole Temperatures To Predict Groundwater Flux, Kevin Heintz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Heat has been effectively used as a groundwater tracer for decades, and high-resolution temperature data can better identify and quantify discrete flow zones. Refinements to the numerical modeling of advective heat transfer in borehole temperature sensing deployments can improve understanding of dynamic hydrogeologic systems. In my thesis, I develop a novel two-dimensional coupled radial groundwater flow and heat transfer numerical model that considers intra-borehole vertical flow. To test the performance of this model, I used finite element analysis to generate synthetic data sets consisting of prescribed variable flow fields and resulting borehole temperatures. I input synthetic temperatures into the two-dimensional …

Estimation Of The Parameters In A Mixture Of Two Normal Distributions And The Generalized Pivotal Quantity Method, Md Faruk Hossain

UNLV Theses, Dissertations, Professional Papers, and Capstones

A pivotal quantity is a random variable that is a function of both the random data and the unknown population parameters and whose probability distribution does not depend on any of the unknown parameters. The population parameters here may include nuisance parameters. Historically, pivotal quantities have been used for the construction of test statistics for hypothesis testing of some of these unknown parameters. They have also been used for the construction of confidence intervals for some of these parameters.Generalized pivotal quantities (GPQ) were introduced by Tsui and Weerahandi (1989) and Weerahandi (1993). A GPQ is a function, not only of …

Use Of Healthcare Utilization Records For Analyzing Trends In Clinical Toxoplasmosis: A Comparison Of Nevada And The United States, Elijah Kreutzer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Toxoplasmosis, a zoonotic disease caused by the parasitic protist Toxoplasma gondii, is a ubiquitous, global public health concern with a wide variety of clinical manifestations. Surveillance for the disease is lacking even in developed countries, and what surveillance is present most often focuses on pregnant women. This research investigated trends in clinical toxoplasmosis in Nevada and nationally to address the lack of knowledge concerning how Nevada discharges compare to national discharges in cases of toxoplasmosis. Specifically, this research sought to determine what characterizes toxoplasmosis in Nevada across inpatient, outpatient, and emergency department settings, as well as how these cases differ …