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Effect Of Flow-Acoustic Resonant Interactions On Aerodynamic Response Of Transitional Airfoils, Joseph Hayden

Doctoral Dissertations and Master's Theses

A high-accuracy numerical study is conducted to examine the impact of flow-acoustic resonant interactions on the aerodynamic response of symmetric and cambered airfoils in the realistic transitional flow regimes with Rec=140,000 and M=0.0465 as well as the low Reynolds number flow regime with Rec=10,000 and M=0.2. The symmetric NACA-0012 and the cambered SD7003 airfoils are investigated at various angles of attack that have been found previously to include both the tone and no-tone producing regimes, with specific focus on the aerodynamic lift response. Additional simulations are conducted with a low-intensity synthetic turbulence introduced upstream of the airfoils in order to …

Application Of Floating Pedal Regenerative Braking For A Rear-Wheel-Drive Parallel-Series Plug-In Hybrid Electric Vehicle With An Automatic Transmission, Dylan Lewis Lewton

Doctoral Dissertations and Master's Theses

As the world continues to move further away from our reliance on fossil fuels, hybrid vehicles are becoming ever more popular. Braking is a system on both hybrid and normal vehicles that involves a significant amount of power and energy. A hybrid can recapture some of that energy using regenerative braking. In this thesis, a method is devised to blend hydraulic and regenerative braking in the most effective manner. A MATLAB Simulink model was built to simulate a parallel-series plug-in hybrid electric vehicle. The model allows for the implementation of a regenerative brake controller that utilizes floating pedal regen, custom …

More Electric Systems Architecture Effect On Business Jet Performance, Kelsey M. Mazur

Doctoral Dissertations and Master's Theses

A more-electric systems architecture, using current state of the art components, is proposed for the business jet Dassault Falcon 2000. A model of the existing aircraft, both of its overall flying characteristics and performance and of its detail systems layout, is created using Pacelab APDc and SysArcc programs. The model is validated with respect to the aircraft published data. Then, another model of the same aircraft is created but, this time, it is for the aircraft with the new architecture and their respective performance is compared. In particular, this results in changes in mission range and the overall system's weight. …

A Detailed Uncertainty Analysis Of Heat Transfer Experiments Using Temperature Sensitive Paint, Anish Prasad

Doctoral Dissertations and Master's Theses

Heat transfer experiments for different cooling techniques for a gas turbine blade are performed and the data are collected via temperature sensitive paint, ammeter, thermocouple and manometer measurement techniques. These data are subjected to uncertainty analysis and the major contributing parameter in the uncertainty is found. A tool to identify the major contributing parameter is devised to reduce the uncertainty in the experiment. Further the effect of temperature difference (surface temperature to bulk temperature) is studied to determine the impact on uncertainty and to determine its importance. The analysis between various implementations of the student’s t distribution are conducted to …

Configuration Validation Of A Novel In-Space Propellant Storage And Transfer System, Priyadarshan Sundararaju

Doctoral Dissertations and Master's Theses

The concept of developing a new technology for on-orbit storage and refueling system has been a great interest among scientists for many decades. This study is about Centaur-based on-orbit propellant storage and transfer. This system takes the advantage of rotational settling to a simple fluid management (FM) system. Specifically, enabling settled fluid transfer and settled pressure control between two tanks. This thesis work focuses on configuration and validation of static and dynamic stability, mass gauging and CFD analysis of the rotational propellant transfer method in space. The application of this technology in Low Earth Orbit (LEO) and Geo-Synchronous Orbit (GEO) …

Turbulence Control In Wall Jets, Jonathan Latim

Doctoral Dissertations and Master's Theses

The turbulent boundary layer has been the focus of many studies over the last century or so due to its engineering significance. Recent studies have shown that the turbulent boundary layer encapsulates extremely energetic large-scale structures which play a much more significant role in its dynamics than has been previously thought. Further, these large scales amplitude and frequency modulate the finer scales of turbulence. This offers a path to control wall turbulence by controlling the large-scales of the flow. The focus of this thesis is to establish ways to manipulate the energy of the large-scale structures in a model turbulent …

Infrasound Propagation In Terrestrial Planetary Atmospheres, Lynsey B. Schroeder

Doctoral Dissertations and Master's Theses

Acoustic waves in the infrasonic frequency range, that is below 10 Hertz, have been observed to propagate to high altitudes in Earth's atmosphere. These waves have many sources, both natural and artificial, such as seismic events, convective storm systems, and nuclear explosions. Here, we seek to better understand the characteristics of atmospheric infrasound- below 0.1 Hz in particular- so as to improve the ability to detect their presence and sources. It is well-known that ambient attributes of an atmosphere, such as temperature, density, and composition, directly affect the propagation and growth of waves, and therefore it is likely that these …

Investigating The Impact Of Green Exercise On Population Health And Well-Being In A Small Community In Ireland:A Novel Approach Using A Natural Laboratory Ecosystem., Nollaig O'Sullivan, Aoife Donnelly, Tadhg Macintyre, Giles Warrington

Articles

Green exercise is defined as undertaking physical activity whilst being directly exposed to nature (Pretty et al., 2005; 2007). Pretty et al. (2003) were among the first wave of researchers to investigate the synergistic benefits of incorporating physical activity and exposure to the natural environment to produce positive psychological affect. Over the past decade, investigations into the possible additive effects on well-being of green exercise and how it can be used as an influential tool to help combat the rising rate of both physical inactivity and non –communicable disease has gained prominence in scientific literature. However, there is still a …

Effect Of A Yogurt Intervention On Adiposity And Metabolic Outcomes In Women, Eryn N. Boyet

Nursing Theses and Dissertations

Over 40% of women in the United States are obese. The Strategic Plan for NIH Obesity Research focuses on “ways to hasten the translation of research evidence from discovery to intervention.” The Strategic Plan also calls on investigators to look at influential points in the lifespan which may affect obesity. Few interventional studies on obesity in women during the perimenopausal time period have been completed. Research in broader populations suggests increased dairy, particularly full-fat products, may decrease central adiposity and improve metabolic indicators of diabetes and cardiovascular disease. The objective of this study was to investigate the effects of dairy …

Three Empirical Investigations Into The Logic Of Evaluation And Valuing Practices, Satoshi Ozeki

Dissertations

This three-paper dissertation investigates the logic of evaluation proposed by Michael Scriven using two different methods of inquiry: content analysis and a survey method. Scriven’s logic of evaluation is one of the central concepts in evaluation, but has not been empirically investigated. Therefore, the purpose of this three-paper dissertation is to accumulate empirical knowledge on Scriven’s logic of evaluation to investigate the extent to which evaluators follow his logic and their perceptions of and familiarity with his logic. Furthermore, this dissertation aims to explore valuing practices in terms of Scriven’s logic of evaluation. Scriven’s logic of evaluation is important because …

Considerations For A Hotel Investment, Stephen Blake Marriott

UNLV Theses, Dissertations, Professional Papers, and Capstones

This writing will provide novice hotel investors, new owners, and hotel associates new insight on hotel investments. This writing discusses industry topics such as: the definition of a hotel asset, an overview of occupancy and transaction levels, different kinds of risk related to hotel investments, location, franchising, the hotel investment cycle, incremental and base impact, and hotel construction related issues. At the conclusion, the reader will be familiar with a few uncommon concepts that affect a hotel investment.

Emotional Labor: Surface Acting A Better Emotional Regulation Strategy For Dealers?, James Luverne Cox

UNLV Theses, Dissertations, Professional Papers, and Capstones

The performing of emotional regulation in the workplace, or emotional labor, has long been researched by scholars. The conclusion that most reached was that individuals performing this regulation were typically better off by changing their emotions felt to their emotions displayed, or what is termed as “deep acting”, rather than “surface acting”, or faking the emotion. This paper will further explore the thoughts behind this argument and propose that dealers that use deep acting are, in fact, more likely to experience emotional burnout due to the inability to constantly change inner emotional states. Additionally, the paper will also seek to …

Avoiding Discrimination And Filtering Of Qualified Candidates By Ats Software, Katarina Drucker

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research paper will be to demonstrate the flaws in present-day hiring systems that may digitally eliminate or discriminate against qualified candidates.

Evaluating The Impact Of A Smoking Ban In Las Vegas Casino Resorts, Emi K. Sakevich

UNLV Theses, Dissertations, Professional Papers, and Capstones

Worldwide, the smoking population decreases, leaving hospitality venues to decide how a change in policy affects their revenues. In spite of the ban, bars, pubs, and restaurants in countries with a smoking ban report a consistent level of revenue. Within the United States, there are varying degrees of a smoking ban, with minimal effect on revenue. In Nevada, the Nevada Clean Indoor Air Act’s commencement coincided with the Great Recession, skewing hospitality revenue numbers as tourism dwindled. Behaviorally, nonsmokers are more likely to avoid areas with smoke, whereas smokers are not as affected by nonsmoking areas. Casinos in Las Vegas …

Hands, And Numbers, And Dots Oh My! Examining The Effect Of Nearby-Hands On Counting And Subitizing, Gabriel Allred

UNLV Theses, Dissertations, Professional Papers, and Capstones

The “nearby-hand” effect (Tseng, Bridgeman, & Juan 2012), an alteration of performance caused by the presence of our hands in the visuospatial area, has been found in learning, attention, and working memory tasks (Brockmole, Davoli, Abrams, & Witt, 2013a). However, no work to date has been published demonstrating a relationship between the nearby-hand effect and judgments of magnitude, including subitizing and counting. It is suggested by Tseng, Bridgeman, and Juan (2012) that nearby-hands affect attentional disengagement, yet little experimental evidence is available to support this notion. Given the serialized nature of counting, which requires attentional disengagement from item to item …

Vulnerability Analysis And Security Framework For Zigbee Communication In Iot, Charbel Azzi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Securing IoT (Internet of Things) systems in general, regardless of the communication technology used, has been the concern of many researchers and private companies. As for ZigBee security concerns, much research and many experiments have been conducted to better predict the nature of potential security threats. In this research we are addressing several ZigBee vulnerabilities by performing first hand experiments and attack simulations on ZigBee protocol. This will allow us to better understand the security issues surveyed and find ways to mitigate them. Based on the attack simulations performed and the survey conducted, we have developed a ZigBee IoT framework …

Homeland, Homestead, And Haven: The Changing Perspectives Of Zion National Park, 1700-1930, Sara Black

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zion National Park is a landscape that the American public celebrates as a unique and beautiful wilderness. However, Zion is much more culturally layered than what most tourists perceive. Numerous Native American cultures have ties to the canyon, including the Southern Paiutes, who used and interacted with this area on a regular basis for at least the last 500 years. For them, it served both substantive and cultural roles in their communities that reinforced their understandings of themselves and their place in the world. For Mormons, who came into the area in the 1860s and quickly dominated the landscape, Zion …

The Iterative Nature Of Descriptive Experience Sampling: Do Interviewees Build Skills Across Sampling Days?, Vincent Peter Brouwers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hurlburt (2009) asserts that iterative training is an essential component of the Descriptive Experience Sampling (DES) method and that interviews of untrained participants are generally characterized by presuppositions about experience and miscommunication rather than pristine experience. Hurlburt and Heavey (2015) further assert that other experience sampling methods (e.g., the Experience Sampling Method) are inadequate due to the minimal training provided in those paradigms. In Study 1, we sought to determine whether DES interviewees decrease in density of subjunctification (i.e., behavioral and verbal indicators that an interviewee is not providing a straightforward account of inner experience) across multiple sampling days, which …

Sulfate Resistance Of Nanosilica Contained Portland Cement Mortars, Iani Batilov Batilov

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soils, sea water and ground water high in sulfates are commonly encountered hostile environments that can attack the structure of concrete via chemical and physical mechanisms which can lead to costly repairs or replacement. Sulfate attack is a slow acting deteriorative phenomenon that can result in cracking, spalling, expansion, increased permeability, paste-to-aggregate bond loss, paste softening, strength loss, and ultimately, progressive failure of concrete. In the presented research study, Portland cement (PC) mortars containing 1.5% to 6.0% nanosilica (nS) cement replacement by weight were tested for sulfate resistance through full submersion in sodium sulfate to simulate external sulfate attack. Mortars …

Nursing Students’ Nonacademic Barriers To Success On High Stakes Exams, Jennifer Bussen Bussen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Every nursing program wants its graduates to pass the NCLEX-RN licensure examination the first time they take it. For those who fail, entry into practice is delayed until they can pass the NCLEX-RN. The nursing programs that graduated students who fail may experience a loss of reputation, decreased numbers of potential applicants, and, ultimately, state board of nursing sanctions. In an effort to determine which students are likely to be successful in taking the NCLEX-RN, many programs have turned to end-of-program predictor exams such as the Health Education System Inc. (HESI) exit examination (E2) (Lauer & Yoho, 2013; Nibert & …

Structuring A Risk-Based Bioassay Program For Uranium Usage In University Laboratories, Johnne' Talia Dawson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Bioassay programs are integral in a radiation safety program. They are used as a method of determining whether individuals working with radioactive material have been exposed and have received a resulting dose. For radionuclides that are not found in nature, determining an exposure is straightforward. However, for a naturally occurring radionuclide like uranium, it is not as straightforward to determine whether a dose is the result of an occupational exposure. The purpose of this project is to address this issue within the University of Nevada, Las Vegas’s (UNLV) bioassay program. This project consisted of two components that studied the effectiveness …

Self-Efficacy In Situation Background Assessment And Recommendation Communication Using Information Technology In Baccalaureate Nursing, Kelly Etcheberry Espinoza

UNLV Theses, Dissertations, Professional Papers, and Capstones

Strong communication skills are essential in establishing a foundation for safe delivery of care. A report from the Institute of Medicine (IOM) titled: To Err is Human: Building a Safer Health System estimated 44,000 to 98,000 deaths occur due to medical errors annually. Communication failure was found to be the root cause in 70% of these cases of medical error. Several studies also indicate communication issues still represent up to 80% of errors and sentinel events in hospitals accredited by the Joint Commission. The IOM's report indicate improving communication in the healthcare setting is essential in reducing medical errors.

In …

An Emg-Based Patient Monitoring System Using Zynq Soc Device, Farhad Fallahlalehzari

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis describes the design, development, and testing of an EMG-based patient monitoring system using the Zynq device. Zynq is a system on chip device designed by Xilinx which consists of an ARM dual cortex-A9 processor as well as an FPGA integrated into one chip. This work also analyzes the performance of image-processing algorithms on this system and compares that performance to more traditional PC-based systems. Image processing algorithms, such as Sobel edge detection, dilation and erosion, could be used in conjunction with a camera for the patient monitoring purposes. These algorithms often perform sub-optimally on processors because of their …

Estimation And Comparison Of Thermoelectric And Pv Solar Water Usage In The Colorado River Basin States, Yuzhen Feng

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the continual expansion of populations in the arid Southwest, energy demands will continue to rise. On the other hand, depleting water levels in reservoirs of the Colorado River Basin is expected to continue as more intense and frequent drought events persist in addition to the rapid development in the region. Currently, the three largest water-use categories in the United States are thermoelectric energy, irrigation, and municipal water, which cumulatively account for 90 percent of the national water use. In the Southwest, most of the total electricity generated is still through thermoelectric means. That is, massive amounts of water are …

Efficient Strategies For Playing The Horn, Jon Allan Holloway

UNLV Theses, Dissertations, Professional Papers, and Capstones

In their pursuit of becoming accomplished performers, horn players spend a great deal of time studying proper brass playing techniques from the great pedagogues. The modern horn is a fairly young instrument (less than two hundred years old) and the most efficient pedagogical approach is still evolving. Because of this, horn players spend a great deal of time studying proper brass playing techniques from the great pedagogues. Books by Philip Farkas, Arnold Jacobs, Raphael Mendez, and more have many theories and exercises on how to breathe, the best way to perfect embouchure development, performance techniques, and more.

Modern pedagogues have …

The Effects Of Orthodontic Appliance Base Plate Material, Pmma, Infused With Silver And A Novel Antibacterial Compound On Biofilm Formation, Ryan D. Jolley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Retention is required in the majority of orthodontic patients throughout the remainder of their life. The traditional Hawley style retainer is still considered by many orthodontic professionals to be the gold standard in retention appliances. The orthodontic population, in general, is at a higher risk for caries due to plaque accumulation from poor diet, suboptimal oral hygiene, and often a lack of motivation. A Hawley retainer that reduces caries-causing oral microbes could improve oral health and be very beneficial to the post-orthodontic patient. Developing methods to safely include antibacterial products within the Hawley retainer’s base plate material could help effect …

Oral Microbial Burden Of Periodontal Pathogens Among Orthodontic Patients, David Jolley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objectives

Many research studies involving orthodontic patients have a natural inclination to focus on changes in levels of cariogenic pathogens after bracket placement, and very few studies examine the role of changes of periodontal pathogens – particularly among adult patients. Interestingly, recent evidence suggests that increased levels of a specific periodontal pathogen, Fusobacterium nucleatum, may elevate risk for development of colon cancer in adults through direct pathways. Based upon this new evidence, the objective of the current study was to screen saliva samples taken from orthodontic patients to determine the prevalence of periodontal pathogens, including F. Nucleatum, T. denticola, and …

The Big Band And The Piano: Nikolai Kapustin’S Variations Op. 41, Ryan Kelly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Much has been written and said on how piano works should almost imitate the sounds of an orchestra to be played well. There is a style and musical language that serious pianists must master in order to play with correct voicing, specific tones, and other techniques that make a piano sound like a full orchestra and thus bring it to life.

While there much written about how the piano should imitate the traditional orchestra in the classical and romantic style, what of the big band? In the last century many works have been written for the piano using jazz rhythms, …

Development Of The K-State (Competence) And Mutagenesis In Stressed Bacillus Subtillis Cells, Amanda Kidman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mutagenesis is central to the evolutionary process. We currently view evolution as a gradual process affecting all cells within a population. However, my project studied an underestimated part of the evolutionary process: mutations generated during stationary phase (caused by nutritional stress or growth arrest) within a subpopulation of cells. I used Bacillus subtilis, a bacterial model for cell growth and differentiation. Stationary-phase cultures of B. subtilis differentiate subpopulations that exhibit different survival strategies including competence, secondary metabolite production, biofilm formation, cannibalism, and endospore formation. The development of competence permits cells to uptake exogenous DNA and incorporate it into their genome. …

A World Of Warning: Exploring U.S. Department Of State Travel Warnings And Alerts, Ryan Daniel Larsen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Travel Warnings and Travel Alerts are documents issued by the United States Department of State to inform U.S. citizens traveling to other countries about the safety conditions of the desired destination. Travel Warnings are created for protracted conditions while Travel Alerts are meant for temporary circumstances. Scant research exists about official State Department travel advice, and there is an absence of knowledge about its components. This qualitative study seeks to answer the questions, what is the nature of State Department Travel Warnings and Alerts and what is their function? This study explores and seeks to describe the nature of Travel …