Digital Commons Network^™

Alkali-~Activated Fly Ash Binders: Feasibility As A Sustainable Alternative To Ordinary Portland Cement For Pre-~Cast Systems, Kimberly Sierra

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fresh, load-dependent, transport, and durability properties of alkali-activated fly ash mortars were studied. The influences of activator concentration, solution-to-binder ratio, curing condition, activator type, and sodium silicate-to-total solution ratio on the properties of the studied alkali-activated mortars were examined. This study was divided in two phases. The first phase dealt with the use of sodium hydroxide as the sole activator. The second phase of the study was divided into two parts, both of which used a combination of sodium hydroxide and sodium silicate as the activator solution. Part I of phase II used elevated temperature curing conditions, whereas part II …

The Visual Framing Of The Three Cycles Of Climate Control In The New York Times 1851 To Present, Jason Lee Thompson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explored the visual framing of climate control in The New York Times through three cycles of media history. Although no peer-reviewed study has explored this specific topic, a wealth of prior communication articles on both the visual and textual aspects of climate change and geoengineering in the media was mined in order to discover the frames present. Once the visual frames of climate control (war, fix, people, and impacts) were revealed a content analysis was conducted in order to see which frame elements were most and least frequent considering the images of climate control. When combining all three …

Architectural Form, Orientation, And Energy For Residential Design In The Southern Nevada Region., Ludwing Vaca

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the population increase, the high demand of energy from the residential sector, as well as the harsh weather conditions of the Las Vegas region, there needs to be careful consideration in the design of new homes. Energy efficiency in a single family residential building can be augmented early in the design process by careful consideration of the building form and orientation. A systematic investigation and analysis was taken to study the effects of five building forms and different orientations along the cardinal points using the software BEopt version 2.4.0.1. To connect the study to real world circumstances, a residential …

A Phenomenology Study Of First-~Year Teachers Looking At The Shared Lived Experience Of Learning To Grade, Brandon Lee Yost

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study describes the phenomenon of how first-year teachers learn to evaluate students learning by (letter) grades. Grades seem simple enough; but in reality, each grade carries serious consequences with it – for either good or bad. For example, grades affect benefits/consequences at home; they affect placement in remedial or advanced courses; they affect grade level promotion; they affect participation in programs, i.e. extracurricular activities like sports; they affect high school graduation, college acceptance, and scholarship eligibility (Brookhart, 1991; Marzano, 2000).

Despite the extreme importance of grades and how they can influence a person’s life over a period of time …

Glass Shards At Pinnacle Point Rock Shelter 5-~6, South Africa: Are They From The Last Super-~Eruption Of Toba?, Amber Elizabeth Ciravolo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cryptotephra, in the form of individual glass shards, have been discovered in paleoarchaeological site PP5-6 North at Pinnacle Point, Western Cape, South Africa. This marks the first documentation of cryptotephra in a South African paleoarchaeological site. PP5-6 North is a rock shelter in the cliffs along the coast of the Western Cape and is one of a series of caves and rock shelters at Pinnacle Point that were inhabited by early modern humans. The presence of cryptotephra at PP5-6 is an important discovery in terms of tephra preservation in cave deposits as well as the possibility of tephra being present …

Optimization Of The Development Process For Air Sampling Filter Standards, Rajah Marie Mena

UNLV Theses, Dissertations, Professional Papers, and Capstones

Air monitoring is an important analysis technique in health physics. However, creating standards which can be used to calibrate detectors used in the analysis of the filters deployed for air monitoring can be challenging. The activity of a standard should be well understood, this includes understanding how the location within the filter affects the final surface emission rate. The purpose of this research is to determine the parameters which most affect uncertainty in an air filter standard and optimize these parameters such that calibrations made with them most accurately reflect the true activity contained inside. A deposition pattern was chosen …

Factor Analysis Of The Sport Interference Checklist With Collegiate Athletes, Travis Albert Loughran

UNLV Theses, Dissertations, Professional Papers, and Capstones

There are a variety of cognitive and behavioral factors that have been indicated to have a negative impact on sport performance. College student-athletes may be at particular risk to evidence problems that interfere with optimal sport performance due to high physical, social, and emotional demands. To fully understand what factors influence student-athlete sport performance, appropriate, psychometrically validated assessment measures are needed. The Sport Interference Checklist (SIC) is an assessment tool that was developed to assess sport performance in both training and competitive situations for student-athletes. The SIC includes two scales, the Problems in Sport Training Scale (PSTS) and the Problems …

A Comparison Of Beliefs And Attitudes About Body Image, Eating And Weight Between Incarcerated And Non-~Incarcerated Females, Anne R. Lindsay

UNLV Theses, Dissertations, Professional Papers, and Capstones

Abstract

Incarceration and substance abuse are two of the largest public health issues in America. While the U.S. makes up only 5% of the world’s population, it accounts for 25% of its prisoners. Incarceration affects more than 2.2 million individuals who will eventually return to their families and communities with ongoing family, social and health issues. Women in prison are a particularly vulnerable and underserved population, generally of low education and socio-economic status and although they account for a small percent of the prison population, many are mothers of young children who are likely to become incarcerated themselves. Substance abuse …

The Comparison Of Two Supine Manikins And The Use Of A Shock And Vibration Isolation System For Litter Patients In Air Medical Transport, Karina Karlui Saenz Acosta

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studies show that repeated shock and vibration during aero medical and ground transport are causing patient pain and may be adversely affecting patients’ medical outcome. Patients with spine and head injuries and other severe neurological injuries are the most vulnerable to repeated shock and vibration exposure caused by the vehicle. It is crucial to minimize the effects of these forces on patients during air and ground medical transport. The development of new medical evacuation platforms creates a need to better understand the effects of human exposure to shock and vibration. The use of human subjects to measure whole body vibration …

What Do We See: Number Line Estimation With Eye Tracking, Sarah Ann Salas

UNLV Theses, Dissertations, Professional Papers, and Capstones

The following paper presents a study investigating adult number line estimation patterns through use of an eye tracker. Estimation patterns were examined by changing the range of the number line on which the estimations occur from the typical ranges of 0-100 and 0-1000 to a more difficult range of 0-723. There were two main conditions of the experiment; in one condition the number to estimate and the number line were presented simultaneously, and in the other condition, the number line presentation was delayed. In each of the two conditions of the experiment, eye fixations and area of interest analysis were …

Characterization Of Gold And Related Mineralization At The North Bullion Carlin System, Railroad Project, A Nevada Carlin-~Type Gold Prospect, Melanie Nicole Newton

UNLV Theses, Dissertations, Professional Papers, and Capstones

A study of the North Bullion Carlin system, a Nevada Carlin-type gold prospect located on trend with the large Carlin-type gold deposits (CTGD) of the Carlin Trend, identified characteristics of ore and alteration mineralization, mineral paragenesis, and pyrite and whole rock geochemistry that are similar to characteristics that typify Carlin-type gold deposits. The North Bullion Carlin system is hosted in Devonian shelf carbonates and the Mississippian overlap assemblage, host rocks that are different from typical CTGD shelf-slope carbonate assemblage host rocks. The mineralogy and ore-stage gold-bearing pyrite rims at North Bullion are not as well developed as they are in …

Dissolution Of Nontronite In Low Water Activity Brines And Implications For The Aqueous History Of Mars, Michael Henry Steiner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Water is essential to life on Earth and is likely to play a role in determining the habitability of other planets. Pure liquid water is not stable on the surface of Mars but brines can temporarily remain liquid, and increasing evidence suggests the presence of recent liquid water, including brines, on Mars. Brines can host life at temperatures as low as -30 ºC and some organisms can live at activities of water as low as 0.61. Therefore, if brines have been present on Mars, they may act as habitable environments.

The Fe-rich smectite nontronite, (CaO0.5,Na)0.3 Fe3+2(Si,Al)4O10(OH)2·nH2O, has been detected on …

Testing Established Models Of Hydrothermal Fluid Distribution Around Porphyry Deposits: The Application Of Fluid Inclusion Research To Porphyry Deposit Exploration, Wyatt Moyer Bain

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Kabba porphyry copper prospect in northwestern Arizona contains two zones of porphyry style mineralization and alteration, which are spatially separated by a north-south trending normal fault. These two zones are referred to as the Kabba footwall and hanging wall and are hypothesized to represent the root and intermediate depth levels of the same porphyry-like hydrothermal system, respectively. If this hypothesis is correct, then fluid inclusions found in the hanging wall and footwall should have the physical and chemical characteristics of fluid inclusions in the root and intermediate depth levels of other known porphyry deposits. Vein and alteration petrography, fluid …

Designing, Building And Testing A Solar Thermoelectric Generation, Steg, For Energy Delivery To Remote Residential Areas In Developing Regions, Yacouba Moumouni

UNLV Theses, Dissertations, Professional Papers, and Capstones

New alternatives and inventive renewable energy techniques which encompass both generation and power management solutions are fundamental for meeting remote residential energy supply and demand today, especially if the grid is quasi-inexistent. Solar thermoelectric generators can be a cost-effective alternative to photovoltaics for a remote residential household power supply. A complete solar thermoelectric energy harvesting system is presented for energy delivery to remote residential areas in developing regions. To this end, the entire system was built, modeled, and then validated with LTspice simulator software via thermal-to-electrical analogy schemes. Valuable data in conjunction with two novel LTspice circuits were obtained, showing …

Safety Analysis Of Freeway Segments With Unobserved Heterogeneity And Second Order Spatial Effects, Eneliko Mujuni Mulokozi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Safety analysis of freeway networks entails the quantification of crash frequency influencing factors which include roadway and traffic characteristics, environmental factors as well as human factors. This quantification can be used to detect locations with large impacts on the occurrence of crashes which in turn assist engineers and planners to improve safety levels of the network. Roadway characteristics are comprised of the physical elements of the road geometry such as section length, median and right shoulders, speed-exchange lanes, the number of main facility as well as geometry of the entrance from and exit to the main freeway facility. Traffic characteristics …

Compression Of Climate Data Through Artificial Neural Networks, Astha Puri

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lately, there has been a tremendous increase in the number of climate monitoring

stations in various parts of the country producing abundant climate data. Among climate data parameters, humidity and temperature are the two parameters influencing hydrological and agricultural processes, weather monitoring, and having critical effect on living organisms. As more data is being generated over time, there is a strong need to develop compression methods for efficient transfer and storage of this data.

The main goal of this thesis is to perform compression of humidity and temperature

data via prediction. As these are critical components of climate, it is …

Ediacaran Ocean Redox Evolution, Swapan Kumar Sahoo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The relative role that environmental versus intrinsic biological factors played in

shaping the history of life on Earth is a fundamental but unanswered question in the

natural sciences. Most famously, it has been heavily debated if the emergence and

diversification of early animals during the Ediacaran Period (ca. 635–541 Ma) was tied to

a rise in atmospheric-oceanic oxygen levels. Temporally discontinuous geochemical data and patchy fossil record in literature are inadequate to chart the Ediacaran redox history and its causal relationship with the biotic evolution. My PhD study aims for a multiproxy geochemical record within a well-established stratigraphic framework of …

Ecosystem Response To Recent Climate Change In Alpine Environments, Patrick Shawn Sawyer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent variations in meteorological conditions indicate the earth’s climate is changing in ways that can impact delicate ecological balances in sensitive regions. These impacts threaten the essential services provided by such ecosystems. Determining how climate changes are affecting the biosphere is essential to adapt and mitigate harmful consequences. In order to mitigate the negative effects of climate change and adapt to shifting ecological resource constraints, it is imperative to locate such changes and determine vulnerability of ecological resources to changing environmental conditions.

Identifying climate driven ecological changes faces numerous challenges given the reliance on vegetation indices as the primary measure …

Rewetting Of Artificially Desiccated Soils: Effect Of Gravity On Vapor-Phase Diffusion, Taylor Arland Ball

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soil desiccation has been suggested as an economically viable alternative for stabilizing water soluble contaminants in deep vadose zones such as at the Hanford Site. This approach would result in a large volume of the vadose zone being dried out in an effort to eliminate the transport mechanism for aqueous phase contaminants. Protecting the top and sides of the desiccated vadose zone from rewetting is a realistic possibility; however, it would be extremely difficult to restrict the upward migration of water from beneath the desiccated zone. One scenario related to the rewetting of the desiccated soil involves the upward migration …

Assessing The Importance Of Nurse Plant Associations To The Growth Of Pre-~Reproductive Yucca Brevifolia, Eric James Chameroy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Facilitation and competition among plant species, in addition to abiotic factors, play an important role in determining plant community structure in arid and semi-arid environments. I conducted a study in Dry Lake Valley, Lincoln County, Nevada, USA to investigate the importance of nurse plant associations to pre-reproductive Yucca brevifolia (Joshua tree). Dry Lake Valley lies within a transition desert between the Mojave and Great Basin Deserts with ecotonal plant communities consisting of species representative of both deserts. A vegetation survey described the communities in which this study was conducted as a Y. brevifolia woodland dominated by an understory of Ephedra …

Simulation Of An Air Cooled Single-Effect Solar Absorption Cooling System With Evacuated Tube Collectors, Mohsen Jahandardoost

UNLV Theses, Dissertations, Professional Papers, and Capstones

Consistently increasing CO2 emission and ozone depletion from synthetic refrigerants are serious environmental issues challenging the scientific community. Absorption cooling systems give scope of utilizing low grade energy source for generating cooling effect. Solar energy is one of these low grade energy sources and with considering the fact that cooling demand increases with the intensity of solar radiation, solar refrigeration has been considered as a logical solution.

This thesis consists of two different simulation stages, in the first stage, a single effect lithium bromide absorption cooling system with constant cooling capacity is modeled and the effect of ambient and generator …

High Pressure X-~Ray Absorption Spectroscopy Studies Of Heavy-~Fermion Cerium And Uranium Compounds, Daniel Antonio

UNLV Theses, Dissertations, Professional Papers, and Capstones

Investigations into f- electron heavy-fermion materials have revealed a wide range of novel behavior. Hydrostatic pressure is a valuable "clean" non-thermal parameter that can be used to systematically study them by tuning their ground state properties. The rare earth compound CeCu2Ge2 shows an unusual two-domed region of unconventional superconductivity under pressure, similar to its isostructural counterpart CeCu2Si2. While the lower pressure dome at about 10 GPa is caused by a magnetic quantum critical point (QCP), the higher one at about 16 GPa is less well understood. Previous structural measurements have indicated that it may be caused by critical valence fluctuations, …

Object Detection And Tracking In Wide Area Surveillance Using Thermal Imagery, Santosh Bhusal

UNLV Theses, Dissertations, Professional Papers, and Capstones

The main objective behind this thesis is to examine how existing vision-based detection and tracking algorithms perform in thermal imagery-based video surveillance. While color-based surveillance has been extensively studied, these techniques can not be used during low illumination, at night, or with lighting changes and shadows which limits their applicability. The main contributions in this thesis are (1) the creation of a new color-thermal dataset, (2) a detailed performance comparison of different color-based detection and tracking algorithms on thermal data and (3) the proposal of an adaptive neural network for false detection rejection.

Since there are not many publicly available …

A Performer's Guide To Dean Gronemeier's Nature Alley, Lonny James Benoit

UNLV Theses, Dissertations, Professional Papers, and Capstones

This document is a resource designed to aid performers in preparation of Dean Gronemeier’s Nature Alley, an advanced four-mallet solo for marimba. A biographical sketch of Dean Gronemeier, general overview of the composition, and the seven main themes of Nature Alley are presented within this document. Specific attention will be given to the musical and technical considerations associated with each of the seven themes.

Generalized Catalan Numbers And Some Divisibility Properties, Jacob Bobrowski

UNLV Theses, Dissertations, Professional Papers, and Capstones

I investigate the divisibility properties of generalized Catalan numbers by ex-

tending known results for ordinary Catalan numbers to their general case. First, I define the general Catalan numbers and provide a new derivation of a known formula. Second, I show several combinatorial representations of generalized Catalan numbers and survey bijections across these representation. Third, I extend several divisibility results proved by Koshy. Finally, I prove conditions under which sufficiently large primes form blocks of divisibility and indivisibility of the generalized Catalan numbers, extending a known result by Alter and Kubota.

Fast Transient Digitizer And Pcb Interface, Kevin Thomas Buck

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis outlines the design, layout and characterization of an application specific integrated circuit (ASIC) and a printed circuit board (PCB) designed to discretize an input signal and read out the data at a user desired interval to replicate the input signal at a lower frequency or pulse rate with no quantization error. The ASIC for this task utilizes 128 individual capacitive storage cells to capture data at approximately 200 ps intervals, thus the chip can capture approximately 25 ns of an input signal. The read out rate can be adjusted to the desired rate by the user by changing …

Chemical And Electronic Structure Of Surfaces And Interfaces In Cadmium Telluride Based Photovoltaic Devices, Douglas Arthur Duncan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The surface and interface properties are of the upmost importance in the understanding, optimization, and application for photovoltaic devices. Often the chemical, electronic, and morphological properties of the films are empirically optimized, however when progress slows, a fundamental understanding of these properties can lead to breakthroughs. In this work, surfaces and interfaces of solar cell-relevant films are probed with a repertoire of X-ray analytical and microanalysis techniques including X-ray photoelectron (XPS), X-ray excited Auger electron (XAES), X-ray emission (XES) spectroscopies, and atomic force (AFM) and scanning electron (SEM) microscopies.

Silicon-based devices currently dominate the solar market, which is rather inflexible …

Fall Detection By Using Video, Robert J. Gripentog

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cameras have become common in our society and as a result there is more video available today than ever before. While the video can be used for entertainment or possibly as storage it can also be used as a sensor capturing crucial information, The information captured can be put to all types of uses, but one particular use is to identify a fall. The importance of identifying a fall can be seen especially in the older population that is affected by falls every year. The falls experienced by the elderly are devastating as they can cause apprehension to normal life …

Thank You For Your Time! Would You Mind Donating To Our Cause? The Effect Of Gratitude On Prosocial Behavior, Matthew L. Hortt

UNLV Theses, Dissertations, Professional Papers, and Capstones

A random assignment experiment examined the effects of three expressions of gratitude on two prosocial behaviors: volunteering and making monetary donations to charitable organizations. The results indicated that two of the expressions of gratitude had a significant opposite effect on the two prosocial behaviors. Both a verbal thank-you speech and a hand written thank-you note, resulted in a significant reduction in the amount of pledged volunteer hours, while resulting in a significant increase in the amount of pledged charitable dollars. The third expression of gratitude, a ten dollar thank-you gift card, produced no significant findings for either prosocial behavior. The …

Study Of Machine Learning Methods In Intelligent Transportation Systems, Vishal Jha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Machine learning and data mining are currently hot topics of research and are applied in database, artificial intelligence, statistics, and so on to discover valuable knowledge and the patterns in big data available to users. Data mining is predominantly about processing unstructured data and extracting meaningful information from them for end users to help take business decisions. Machine learning techniques use mathematical algorithms to find a pattern or extract meaning out from big data. The popularity of such techniques in analyzing business problems has been enhanced by the arrival of big data.

The main objective of this thesis is to …