Digital Commons Network^™

Bulbous Pier: Alternative To Bridge Pier Extensions, Amilcar Chavez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Bridge deck splashing causes deterioration to the bridge structure and renders the bridge unsafe for motorist and pedestrians. The traditional countermeasure for bridge deck splashing is pier extension, the pier extension moves the pier wave away from the bridge deck, but retrofitting existing bridges with pier extensions is costly. This research proposes the bulbous pier concept as an alternative to pier extension.

The decrease in the pier wave produced by the bulb is due to energy subtracted by the bulb via two forces, the viscous resistance, and the wave-making resistance. The proposed mathematical model for the bulbous pier design follows …

Trace Element Variations In A Stalagmite From Southwest Mexico: Implications For Paleoclimate, Chad Michael Crotty

UNLV Theses, Dissertations, Professional Papers, and Capstones

The combination of stable isotope and trace element concentrations in speleothems has been shown to be a valuable indicator for interpreting paleoclimatic conditions. Anomalous spikes in trace element concentrations have also been shown to indicate anthropogenic environmental changes to the surface, such as deforestation events. In this study, trace element concentrations (24Mg, 25Mg, 84Sr, 88Sr, 137Ba, and 238U) of a stalagmite (JX-6) from Juxtlahuaca Cave, in southwestern Mexico, were measured using an inductively coupled plasma mass spectrometer (ICP-MS). These trace element concentrations were compared to previously analyzed δ18O and δ13C values from JX-6, and to the results of previous studies …

Adaptive, Neural And Robust Control Of Wing-Rock And Aeroelastic System, Prince Ghorawat

UNLV Theses, Dissertations, Professional Papers, and Capstones

Modern aircraft exhibit wing-rock phenomenon and aeroelastic instability. Wingrock (roll single degree of freedom motion) and aeroelastic systems' (two degrees of freedom) behavior are described by complex nonlinear differential equations. The nonlinearities in the dynamics of these systems give rise to limit cycle oscillations beyond critical speed of aircraft. The onset of wing-rock and aeroelastic instability limits the performance of aircraft and can even lead to catastrophic consequences. Therefore, control of wing-rock motion and stabilization of aeroelastic systems are important. In the past, several studies have been made and experimental and analytical results have been obtained to explain the wing-rock …

Experience-Specific And Domain-General Effects On Simple And Complex Meter Processing, Sangeeta Gupta

UNLV Theses, Dissertations, Professional Papers, and Capstones

Our ability to process rhythmic patterns is constrained by the complexity of its interval structure. The goal of the present study was to explore the cognitive demands and neural mechanisms for processing simple and complex meters, and the extent to which they are modulated by culture-specific experience. The first experiment explored the argument that perception of rhythm is guided by a domain-general ability to process quantity, and that processing simple and complex meter rhythms requires different cognitive strategies. Rhythm perception was assessed by testing listeners’ ability to detect disruptions in simple and complex meter melodies. Proficiency with numerosity judgments was …

Risk Misperception And Selection In Insurance Markets: An Application To Demand For Cancer Insurance, David S. Hales

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spinnewijn (2013) posits that optimism about risk and the efficacy of risk-reducing effort could cause selection in insurance markets. We test for this using a survey of 474 subjects’ demand for hypothetical cancer insurance. We elicit perceptions of baseline cancer risk and control efficacy and combine these with subject-specific cancer risks predicted by the Harvard Cancer Risk Index to develop measures of baseline and control optimism. We find that only 23 percent of our subjects would purchase a fair insurance contract aligned to their true risk type. Of these subjects, 94 percent also overinvest in prevention, leading to advantageous selection.

Playful Aggression And The Situational Contexts That Affect Perceptions, Jennifer Hart

UNLV Theses, Dissertations, Professional Papers, and Capstones

Play is considered a fundamental tool for early childhood education practices as it provides numerous developmental benefits for young children. However, not all play is viewed by children, parents, and early childhood educators the same, especially playful aggression. For example, rough-and-tumble play, risky play, superhero play, “bad guy” play, active pretend play, play fighting, big body play, war play, gun play, and physically active and imaginative play are types of playful aggression that benefits young children’s development; but are often viewed negatively by the adults who observe it. The contextual factors that influence the development of these conflicting perceptions—the motivation …

Framing Reality: Portrayals Of Climate Change In The "Las Vegas Review-Journal", 1997-2014, Jason Ryan Holley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Discussions of human-caused climate change have become an increasingly salient artifact of various media in recent years. With regard to print media in particular, scholars have uncovered general increases in the frequencies with which climate change articles are published, tantamount to the annual reports from the Intergovernmental Panel on Climate Change (IPCC) advocating the detriments of human activities (particularly carbon dioxide emissions) on the natural environment. Among such reports—be they scientific or anecdotal—writers and journalists have had to interpret the ongoing discussions and evidence surrounding climate change, and develop schemas (or frames) in which to situate arguments. These arguments have …

High Pressure Behavior Of Mullite-Type Oxides: Phase Transitions, Amorphization, Negative Linear Compressibility And Microstructural Implications, Patricia Kalita

UNLV Theses, Dissertations, Professional Papers, and Capstones

Even though mullite occurs rarely in nature, it is perhaps one of the most important phases in both traditional and advanced ceramics. Existing and emerging applications of mullite and mullite-type materials include: high-temperature composites, aerospace materials, ballistic shielding for military applications and even non-linear optical materials. There are many uncertainties regarding the basic physical properties of mullite-type materials, particularly in terms of their high-pressure structural stability and mechanical behavior that are important to address for emerging applications of mullites as engineering materials. This work is the first reported comprehensive investigation of the high –pressure structural behavior of several different mullites …

Modeling Background Radiation Using Geochemical Data, Kara Marsac

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aerial gamma ray surveys have many applications in geology and science in general, such as locating mining prospects, defining radioactive plumes, and detecting nuclear weapons. Unfortunately there is currently no simple way to separate the natural gamma radiation of soil and rocks from that of contaminants such as radioactive plumes. This project used geochemical data (uranium, potassium and thorium concentrations) collected from national databases, private companies, and the NURE (National Uranium Resource Evaluation) Survey, to create forward models of exposure rates measured by aerial gamma ray surveys. We developed these techniques using an area in north central Arizona known as …

Exact Statistical Inferences For Functions Of Parameters Of The Log-Gamma Distribution, Joseph F. Mcdonald

UNLV Theses, Dissertations, Professional Papers, and Capstones

The log-gamma model has been used extensively for flood frequency analysis and is an important distribution in reliability, medical and other areas of lifetime testing. Conventional methods fails to provide exact solutions for the log-gamma model while asymptotic methods provide approximate solutions that often have poor performance for typical sample sizes. The two parameter log-gamma distribution is examined using the generalized p-value approach. The methods are exact in the sense that the tests and the confidence intervals are based on exact probability statements rather than on asymptotic approximations. Exact tests and exact confidence intervals for the parameter of interest based …

A Process For Optimal Resource Allocation For Integrated Resorts, Benjamin Mammina

UNLV Theses, Dissertations, Professional Papers, and Capstones

For anyone involved in the development of casinos or Integrated Resorts the process of planning a successful project can be rather cumbersome, arbitrary and lacking of business data to make sound financial decisions. This study will organize that process to reduce those difficulties and identify those Resources needed to provide optimal results for return on investment (ROI), total investment (TI) and overall size of the project (SF).

To determine the size of an Integrated Resort (IR) owners and developers tend to look at the building characteristics of competing or admired projects and then set their Resource parameters such as: 2000 …

Generalized Markoff Equations, Euclid Trees, And Chebyshev Polynomials, Donald Joseph Mcginn

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Markoff equation is x^2+y^2+z^2 = 3xyz, and all of the positive integer solutions

of this equation occur on one tree generated from (1, 1, 1), which is called the

Markoff tree. In this paper, we consider trees of solutions to equations of the form

x^2 + y^2 + z^2 = xyz + A. We say a tree of solutions satisfies the unicity condition

if the maximum element of an ordered triple in the tree uniquely determines the

other two. The unicity conjecture says that the Markoff tree satisifies the unicity

condition. In this paper, we show that there exists …

A Comparison Of Recent Results On The Unicity Conjecture Of The Markoff Equation, Brandon John Metz

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis we discuss the positive integer solutions to the equation known as the Markoff equation

x² + y² + z² = 3xyz.

Each solution to the equation is a permutation of a triple (x,y,z) with [mathematical equation refer to PDF] which is called a Markoff triple and each integer of the triple is referred to as a Markoff number.

In 1913, Frobenius conjectured that given an ordered Markoff triple (x,y,z), then both x and y are uniquely determined by z. In other words, if both (x₁,y₁,z) and (x₂,y_{2 …}

Beryllium Is A Potent And Unique Gsk-3Β Inhibitor With Potential To Differentially Regulate Glycogen Synthase And Β-Catenin, Ata Ur Rahman Mohammed Abdul

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glycogen Synthase Kinase-3β (GSK-3β) is an important serine/threonine kinase that phosphorylates/regulates diverse and metabolically important proteins. Some of the important substrates of GSK-3β are glycogen synthase, tau, β-catenin, cyclin D1, axin, c-jun, c-myc, Heat Shock Factor–1, BCL-3, CREB, Histone H1.5, mdm2, p21 (CIP1), pyruvate dehydrogenase and many more. De-regulation of GSK-3β has been implicated in diseases like cancer, Alzheimer’s disease, bipolar disorder and type 2 diabetes mellitus. Currently, GSK-3β is one of the most widely studied proteins and there is a great interest in developing potent and efficient GSK-3β-inhibitors for research as well as therapeutic purposes. We demonstrate that beryllium …

Validation And Reliability Of The Hexoskin And Fitbit Flex Wearable Bio Collection Devices, Jeffrey Montes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to investigate whether the Hexoskin shirt and the wrist worn Fitbit Flex activity monitor were both valid and reliable for the physiological functions they were designed to monitor. Heart rate (beats·min-1), respiratory rate (breaths·min-1), step count, and energy expenditure results were collected for the Hexoskin. Step count and energy expenditure were collected for the Fitbit Flex. 49 adolescent participants performed a walking treadmill protocol at 1.5 mph, 2.5 mph, and 3.5 mph for 3 minutes at each speed. 46 subjects returned to perform the same protocol a second time. 31 of the participants were …

Survival Of The Fittest: The Role Of Linguistic Modification In Nursing Education, Brenda Strauch Moore

UNLV Theses, Dissertations, Professional Papers, and Capstones

This project’s long term goal was to improve English-as-a-Second-Language (ESL) nursing student retention. Improving the quality of multiple choice exams is a first crucial step. ESL students find multiple-choice exams to be one of the most challenging aspects of nursing school. One reason for this is the presence of linguistic errors in exam questions. Linguistic errors include: irrelevant question content, poor sentence structure, and culturally biased words or phrases. Non-ESL students are less affected because exams are written in their native language. Linguistic modification, as part of best practices in item writing, removes these types of errors. The U.S. Department …

Situational Assessment Using Graph Comparison, Pavan Kumar Pallapunidi

UNLV Theses, Dissertations, Professional Papers, and Capstones

In strategic operations, the assessment of any given situation is very important and may trigger the development of a mission plan. The mission plan consists of various actions that should be executed in order to successfully mitigate the situation. For a new mission plan to be designed or implemented, the effect of the previous mission plan should be accessed. These mission plans use various sensors to collect the data which can be very large and aggregate them to obtain detailed information of the situation. In order to implement an effective mission plan the current situation has to be assessed effectively. …

Tracking And Monitoring Unmanned Aircraft Systems Activities With Crowd-Based Mobile Apps, Tejaswini Papireddy

UNLV Theses, Dissertations, Professional Papers, and Capstones

An Unmanned Aircraft System(UAS) is an aircraft without human pilot onboard. They can be controlled remotely from a ground control station (GCS) or can fly autonomously based on pre-programmed flight plans. Tracking and monitoring these UASs activities in the National Airspace System (NAS) is one of the major challenges related to UAS. This system tracks a set of UASs at a given point of time based on the user-submitted tracking information. This thesis presents the basic knowledge of UAS, types of UAS, advantages, and challenges with UASs. The implemented Android application allows the users to submit the observed UAS information …

A Multi-Level Trust Management Scheme For The Internet Of Things, Anusha Ramanathan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The significance of the Internet of Things (IoT) in current trends is continuously rising. It is an umbrella term that signifies a network of physical devices that are embedded with electronics, software, sensors and connectivity that enable greater functions and services through the exchange of data accomplished through interconnection. The applications of the IoT are varied and numerous; they range from relatively simple home automation scenarios to the much more complex scenarios of interconnected smart cities. IoT is expected to dominate the future with huge amounts of content oriented traffic that is a result of intensive interactions between the millions …

Partnering With The Community For Establishment Of Alternate Care Sites During Disasters Or Emergencies: A Staff Training Matrix, Jean Marie Roberts

UNLV Theses, Dissertations, Professional Papers, and Capstones

An approach to fulfill a need for additional hospital beds during emergency and disaster situations has been establishment of alternate care sites (ACS). Kern County, California, with a population of about 856,000 and approximately 1,500 hospital beds, is at significant risk for inability to care for the medical needs of its residents in the face of a disaster or an emergency. Even the most conservative estimates of additional hospital beds requirements in a disaster or emergency would indicate the need for nine to ten ACSs accommodating up to 50 patients each in Kern County.

Recognizing the need for alternatives to …

Lead Hazard Control In Henderson, Nevada: Identifying Critical Areas And The Associated Costs, Khaye Gerazel Arcilla Rufin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lead poisoning is a common, yet preventable childhood health problem in the United States today. Studies show statistically significant (p < .05) associations between higher childhood lead exposure and subsequent negative developmental outcomes. Since 1993, the U.S. Department of Housing and Urban Development (HUD) Lead Hazard Control (LHC) Grant Program has devoted more than $1 billion in funding to several cities.

This study investigated a total of n=75 homes enrolled into the Henderson Lead Hazard Control and Healthy Homes Program (HLHCHHP) from December 2013 – February 2015. A logistic regression was performed to ascertain the frequency of lead-based paint (LBP) found in homes based on the year it was constructed. Of the 75 enrolled and tested for LBP, 58 homes (77.3%) were found to contain LBP and 17 homes (22.7%) did not contain LBP. The significance value of p=0.013 shows that …

Negative Impacts Of Teacher Evaluation Reform: The Role Of Federal Policy In Student Achievement And Teacher Quality, Allison Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this sequential transformative study was to elucidate the negative experiences of teachers with performance evaluations and to juxtapose the intended use of current popular teacher evaluation reform movements to the evident implementation. One may quickly assume that negative experiences with evaluation are a result of unsatisfactory teaching practices. However, this may not accurately explain the negative experiences. This study focused on the negative experience of teacher evaluation to provide a broader understanding of the impact of new evaluation policy reform on student achievement and teacher quality. Five data sources were analyzed: PAR policy, a teacher survey, district …

Concurrent Lazy Splay Tree With Relativistic Programming Approach, Jaya Ram Sedai

UNLV Theses, Dissertations, Professional Papers, and Capstones

A splay tree is a self-adjusting binary search tree in which recently accessed elements are quick to access again. Splay operation causes the sequential bottleneck at the root of the tree in concurrent environment. The Lazy splaying is to rotate the tree at most one per access so that very frequently accessed item does full splaying. We present the RCU (Read-copy-update) based synchronization mechanism for splay tree operations which allows reads to occur concurrently with updates such as deletion and restructuring by splay rotation. This approach is generalized as relativistic programming. The relativistic programming is the programming technique for concurrent …

Concurrent Non-Blocking Skip List Using Multi-Word Compare And Swap Operation, Anish Ratna Tuladhar

UNLV Theses, Dissertations, Professional Papers, and Capstones

We present a non-blocking lock-free implementation of skip list data structure using multi word compare and swap (CASN) operation. This operation is designed to work on arbitrary number of memory locations as a single atomic step. We discuss the implementation details of CASN operation which only utilizes the single word compare and swap atomic primitive found in most of the contemporary multiprocessor systems. Using this operation, we first design lock-free algorithms to implement various operations on linked list data structure, then extend it to design skip lists. Skip list is a probabilistic data structure composed of linked lists stacked together …

Moon Called Her Visage Woman, Ann Michelle Villanueva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Moon Called Her Visage Woman is a thesis-length collection of poetry submitted in fulfillment of the MFA program in Creative Writing. It is comprised of short poems, generally thirty lines or fewer, and is influenced by the works of John Ashbery and Emily Dickinson. The collection contains three main sections, titled Petals for the Divide, Settled Beer Awaits Us, and Postscript: Lions, which explore the possibility of the feminine as a redemptive force in society and nature.

A Study Of Sequential Inference For The Risk Ratio And Measure Of Reduction Of Two Binomials, Zhou Wang

UNLV Theses, Dissertations, Professional Papers, and Capstones

The binomial distribution is one of the most commonly and widely occurring probabilistic phenomena in our lives. Since observations from independent Bernoulli trials yield a dichotomous type, the distribution of sequences provides the basis and clue for statistical formulations of a wide variety of problems.

Occasionally, the core of biomedical studies is related to the comparison and evaluation of the risks of events or outcomes of interest in comparing populations under study. For instance, one wishes to compare two groups of subjects drawn from two independent populations. Then, two sample proportions play central roles in those comparisons. One of the …

Effect Of Void Geometry On Strength, Stiffness, And Failure Modes Of Rock-Like Materials, Omed Yousif

UNLV Theses, Dissertations, Professional Papers, and Capstones

The host rock of portion of the first proposed high-level nuclear waste repository in the United States of America (Yucca Mountain, Nevada) is tuff rock that contains voids (lithophysae) with different shapes, sizes, and distributions. The existence of these voids can cause a dramatic change in the rock's mechanical properties such as uniaxial compressive strength, UCS, and Young's modulus, E. Accordingly, in an experimental program, the effects of void existence on the engineering properties of the tuff rocks was explored in a work of US Department of Energy conducted in the Department of Civil and Environmental Engineering and Construction of …

Reducing Health Disparities Through The 2015 Mcat: A Bold Goal Requiring On-Going Assessment, Aliya G. Feroe, Stephen F. Loebs

Journal of Health Disparities Research and Practice

There is broad consensus that reduction in health care disparities is an important and multi-faceted challenge. One possible approach, among many others, starts with the attraction of women and men to the field of medicine who have a broad based education and who can demonstrate cultural understanding and sensitivity. In this context, the Medical College Admissions Test (MCAT) has been revised, effective in 2015, to include many additional questions concerning the psychological, social, and behavioral sciences. There are important assumptions fueling the revised Medical College Admissions Test (MCAT) and these will need to be tested. These assumptions range from influencing …

Unlv Magazine, Tony Allen, Michael Blasky, Afsha Bawany, Shane Bevell, Su Kim Chung, Holly Ivy Devore, Julie Ann Formoso, Madeline Gray, Matthew Rakola, Brian Sodoma, David Stroud

UNLV Magazine

No abstract provided.

Parameters Identification For A Composite Piezoelectric Actuator Dynamics, Mohammad Saadeh, Mohamed Trabia

Mechanical Engineering Faculty Research

This work presents an approach for identifying the model of a composite piezoelectric (PZT) bimorph actuator dynamics, with the objective of creating a robust model that can be used under various operating conditions. This actuator exhibits nonlinear behavior that can be described using backlash and hysteresis. A linear dynamic model with a damping matrix that incorporates the Bouc–Wen hysteresis model and the backlash operators is developed. This work proposes identifying the actuator’s model parameters using the hybrid master-slave genetic algorithm neural network (HGANN). In this algorithm, the neural network exploits the ability of the genetic algorithm to search globally to …