Digital Commons Network^™

Using Infrasound Waves To Monitor Tropospheric Weather And Crater Morphology Changes, Hugo David Ortiz

Boise State University Theses and Dissertations

Infrasound waves generated during volcanic eruptions and recorded near the vent are used to study both changing atmospheric conditions and volcano eruption source characteristics. Infrasound data were recorded for a 32 month period at Volcán Tungurahua (Ecuador) by a five-station network located within 6.5 km from the vent. Infrasound detections made through cross-network correlation indicate cyclic eruptive behavior, which is corroborated by reports from the Ecuadorian monitoring agency. Cross-network correlation lag times are used to compute _10 m resolution infrasound source positions, which take into account NOAA models of local wind and temperature. Variable infrasound-derived source locations suggests source migration …

Development Of Fault Tolerant Adaptive Control Laws For Aerospace Systems, Andres E. Perez Rocha

Doctoral Dissertations and Master's Theses

The main topic of this dissertation is the design, development and implementation of intelligent adaptive control techniques designed to maintain healthy performance of aerospace systems subjected to malfunctions, external parameter changes and/or unmodeled dynamics. The dissertation is focused on the development of novel adaptive control configurations that rely on non-linear functions that appear in the immune system of living organisms as main source of adaptation. One of the main goals of this dissertation is to demonstrate that these novel adaptive control architectures are able to improve overall performance and protect the system while reducing control effort and maintaining adequate operation …

Effect Of Slot Span On Wing Performance, Juan F. Granizo

Doctoral Dissertations and Master's Theses

This report presents new numerically-derived correlations to estimate the aerodynamic properties of a three-dimensional wing that features a partial to full span fixed slot. Fixed slots have been thoroughly studied in the past with regards to their operation and the relation between slot geometry and wing performance. There have also been many studies on the advantages and disadvantages of tip-slotted wings and the comparison between these and full-slotted wings. Up to this point however, a study on the effects of slot span on wing performance has not been performed. Effect of slot span on wing performance is evaluated in an …

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. …

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 …

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 …

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 …

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 …

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 …

Acoustic Detection, Source Separation, And Classification Algorithms For Unmanned Aerial Vehicles In Wildlife Monitoring And Poaching, Carlo Lopez-Tello

UNLV Theses, Dissertations, Professional Papers, and Capstones

This work focuses on the problem of acoustic detection, source separation, and classification under noisy conditions. The goal of this work is to develop a system that is able to detect poachers and animals in the wild by using microphones mounted on unmanned aerial vehicles (UAVs). The classes of signals used to detect wildlife and poachers include: mammals, birds, vehicles and firearms. The noise signals under consideration include: colored noises, UAV propeller and wind noises.

The system consists of three sub-systems: source separation (SS), signal detection, and signal classification. Non-negative Matrix Factorization (NMF) is used for source separation, and random …

The Effect Of Gender, Not Math Anxiety, On Working Memory Tasks, Amy J. Mcauley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Math anxiety is defined as “feelings of tension and anxiety that interfere with the manipulation of numbers and the solving of mathematical problems in a wide variety of ordinary life and academic situations.” (Richardson & Suinn, 1972). The effects math anxiety has on various tasks are overwhelming. Math anxiety has been shown to relate to poor educational attainment and avoidance of math courses (Hembree 1990). Research has shown that math anxiety can affect simple process like counting (Maloney, Risko, Ansari, & Fugelsang, 2010) to taxing working memory while solving a math problem (Ashcraft & Kirk, 2001). Additionally, gender also plays …

From Access To Excess: Agribusiness, Federal Water Programs, And The Historical Roots Of The California Water Crisis, Tracy Marie Neblina

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this paper is to show the link between water use, land consolidation, agribusinesses, and the water crisis that California began to experience in 2011. In order to better understand the relationship between the growth of agribusiness in the state and the evolution of water policy, this paper explores the historical context of land policy, the growth of farming in the San Joaquin Valley, and the development of federally funded water projects in the Central Valley. Years of expanding farmland and use of surface and underground water with limited regulation played an important role in exacerbating California’s water …

Interference Effects Of Urban Rubble On The Radioanalytical Analysis Of Strontium, Derek Roger Mclain

UNLV Theses, Dissertations, Professional Papers, and Capstones

Most current radioanalytical protocols have been developed for the analysis of air, water, soil and bioassay samples. While these protocols build the foundation of operational environmental monitoring, they are not necessarily suitable for the analysis of samples that will be encountered in the aftermath of a nuclear incident. In such a situation, it will be important to characterize the isotopes of interest present in the affected area to obtain signatures for nuclear forensics and ensure the appropriate response. Specifically, this research is aimed at the determination of strontium-90 and its separation from zirconium-90 in a post-detonation situation.

Strontium-90’s relatively long …

Assessing A Potential Paleothermal Anomaly Near A Salt Wall Using (U-Th)/He Thermochronology And Silica Cementation Analysis, Onion Creek, Utah, Richard Gregory Ness

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Onion Creek salt wall in Fisher Valley, Utah is an exposed salt structure that lies adjacent to sandstones of the Permian age Cutler Group. The thermal conductivity of salt is two to four times greater than other sedimentary rocks and has been shown to act as a regional conduit for heat flow which has implications for petroleum systems in hydrocarbon exploration. Numerical models predict that thermal anomalies should extend 1.5 times the radius of a salt structure into adjacent strata. I hypothesized that an elevated paleothermal anomaly exists in sandstones of the Cutler Group where they are located near …

Canovas Canyon Rhyolites, Jemez Volcanic Field, New Mexico: Discrete Source Magmas, Or A Potential Caldera Forming Magma System?, Penelope Marie Padmore

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Jemez volcanic field (JVF), New Mexico, is a caldera-forming volcanic field located at the junction of the Rio Grande Rift and the Jemez Lineament. The JVF is one of three large North American caldera-forming systems, including Long Valley, California and Yellowstone Plateau volcanic field, Wyoming, which have been active during the Quaternary. Because portions of the JVF are unusually well preserved, it offers a rare opportunity to study how such systems develop. Insight into the history of caldera-forming systems will contribute to the understanding of their potential future behavior. In the case of Yellowstone and Long Valley, that insight …

A Case Study On Enterprise Content Management Using Agile Methodology, Rohit Raj

UNLV Theses, Dissertations, Professional Papers, and Capstones

Every organization has the need to create, classify, manage and archive information so that it is accessible when they need it. The amount of data or information needed for an organization to build their business and for them to be more positive in today’s business world is increasing exponentially, which also includes unstructured data or unstructured content. It is not appropriate only to “manage” content, but whether the correct version of the data or document or record can be accessed. Enterprise Content Management is an efficient collection and planning of information that is to be used by a very particular …

Process Development For The Fabrication Of Semiconductor Devices And Circuits Using Spin-On Dopant, Richard R. Ryan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traditional approaches to semiconductor device fabrication are expensive and time consuming, making them out of reach for most universities and colleges. The objective of this thesis is to develop a process by which semiconductor devices and circuits can be implemented completely in-house using spin-on dopants (SODs), and low-cost transparency masks, to significantly reduce the lead time, complexity, and cost associated with device fabrication. This will allow hands on fabrication experience for students at universities and colleges without the traditional expensive device fabrication facilities. In addition, it will also allow students and professors to design, fabricate and test semiconductor devices and …

Analyses Of Streamflow Change Patterns And Correlation Of These Changes With Sea-Surface Temperature Fluctuations, Kazi Ali Tamaddun

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis presents a comprehensive statistical analysis that determines the direction, rate, and interval of significant streamflow change patterns in the continental U.S. and correlates these changes with sea-surface temperature fluctuations. First, by using two non-parametric tests, namely, the Mann-Kendall trend test and the Pettitt’s test, the presence of long-term trends and abrupt shifts were determined at 10% significance level over continuously adjustable periods that stretched from 1903 to 2012. Modified versions of the tests were applied to account for the presence of persistence (autocorrelation) in data. Theil-Sen slope was determined to evaluate the rate of change across multiple temporal …

Enhancing The Draft Assembly With Minhash, Saju Varghese

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis, we report on the use of minhash techniques to improve the draft assembly of a genome mapping. More specifically, we use minhash to compare the scaffolds of sea urchin and sea cucumber genomes.

One of the main contributions of this thesis is the implementation of minhash with the Message Passing Interface (MPI) utilizing Intel Phi co-processors. It is shown that our implementation significantly reduces the processing time for identification of k-mer similarities.

Statistical Inference Of Genetic Forces Using A Poisson Random Field Model With Non-Constant Population Size, Jianbo Xu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The fidelity of DNA sequence data makes it a perfect platform for quantitatively analyzing and interpreting evolutionary progress. By comparing the information between intraspecific polymorphism with interspecific divergence in two sibling species, the well established Poisson Random Field theory offers a statistical framework with which various genetic parameters such as natural selection intensity, mutation rate and speciation time can be effectively estimated. A recently developed time-inhomogeneous PRF model has reinforced the original method by removing the assumption of stationary site frequency, but it preserves the condition that the two sibling species share same effective population size with their ancestral species. …

Development Of Printed Cross-Functional Sensors For Gearbox Lubricant Prognostics, John Omondi Manyala

Dissertations

Lubricant oil degradation is a major cause of failures in transportation machinery such as pumps, engines, and gearboxes. Proactive oil maintenance techniques such as the off-line oil sampling for laboratory analysis are not only costly but are also susceptible to various influences during the oil sampling, transportation and testing. In this study, an on-line oil condition monitoring system is presented with an integrated predictive prognostic scheme, describing the evolution in time of the identified fault indicators for purposes of estimating the remaining useful life of oil in real-time inside the gearbox. The proposed methodology facilitates on-demand gearbox maintenance rather than …

Marine Microalgae: Climate, Energy, And Food Security From The Sea, Charles H. Greene, Mark E. Huntley, Ian Archibald, Léda N. Gerber, Deborah L. Sills, Joe Granados, Jefferson W. Tester, Colin M. Beal, Michael J. Walsh, Robert R. Bidigare, Susan L. Brown, William P. Cochlan, Zackary I. Johnson, Xin Gen Lei, Stephen C. Machesky, Donald Redalje, Ruth E. Richardson, Viswanath Kiron, Virginia Corless

Faculty Publications

Climate, energy, and food security are three of the greatest challenges society faces this century. Solutions for mitigating the effects of climate change often conflict with solutions for ensuring society’s future energy and food requirements. For example, BioEnergy with Carbon Capture and Storage (BECCS) has been proposed as an important method for achieving negative CO2 emissions later this century while simultaneously producing renewable energy on a global scale. However, BECCS has many negative environmental consequences for land, nutrient, and water use as well as biodiversity and food production. In contrast, large-scale industrial cultivation of marine microalgae can provide society with …

Error Analysis Of An Hdg Method For A Distributed Optimal, Huiqing Zhu, Fatih Celiker

Faculty Publications

In this paper, we present a priori error analysis of a hybridizable discontinuous Galerkin (HDG) method for a distributed optimal control problem governed by diffusion equations. The error estimates are established based on the projection-based approach recently used to analyze these methods for the diffusion equation. We proved that for approximations of degree k on conforming meshes, the orders of convergence of the approximation to fluxes and scalar variables are k+1 when the local stabilization parameter is suitably chosen.

Towards Multipurpose Readability Assessment, Ion Madrazo

Boise State University Theses and Dissertations

Readability refers to the ease with which a reader can understand a text. Automatic readability assessment has been widely studied over the past 50 years. However, most of the studies focus on the development of tools that apply either to a single language, domain, or document type. This supposes duplicate efforts for both developers, who need to integrate multiple tools in their systems, and final users, who have to deal with incompatibilities among the readability scales of different tools. In this manuscript, we present MultiRead, a multipurpose readability assessment tool capable of predicting the reading difficulty of texts of varied …

Estimating Length Statistics Of Aggregate Fried Potato Product Via Electromagnetic Radiation Attenuation, Jesse Lovitt

Boise State University Theses and Dissertations

This work investigates the feasibility of using non-destructive testing, in particular radiation tomography, to recover length statistics from aggregates of fried batonnet cut potato. Non-destructive testing comprises a variety of useful techniques for determining properties of an object that might otherwise require altering or destroying the object physically. Tomography is a common form of non-destructive testing used primarily to infer properties internal to an object. This process involves exposing the object of interest to radiation and detecting the quantity of radiation energy that penetrates the object, usually resulting in a grey scale image.

To do this, an artificial data pipeline …

Examining The Influence Of Number Line Fraction Task Characteristics On Student Work, Sharlee Hatch

Boise State University Theses and Dissertations

Research supports the claim that classrooms with teachers who respond to student thinking in the mathematics classroom will see greater student gains and student success (Lamon, 1996; Sleep & Boerst, 2012). The topic of fractions is both difficult to teach and learn, but has important implications on future success in mathematics and in life. This study set out to explore the ways in which student work is influenced by characteristics of number line fraction tasks. By examining task type, number line structure, and number choice this study shares the way these task characteristics influenced student strategies. The relationship between task …

A 10-Point Approximating Subdivision Scheme Based On Least Squares Technique, Ghulam Mustafa, Muhammad T. Iqbal

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a 10-point approximating subdivision scheme is presented. Least squares technique for fitting the polynomial of degree 9 to data is used to develop this scheme. The proposed strategy can be used to generate a family of schemes. The important characteristics of the scheme are also discussed. Graphical efficiency of the scheme is shown by applying it on different types of data.