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(U-Th)/He Studies Of The Southern Snake Range Metamorphic Core Complex, Nv And Gypsum Valley Salt Wall, Paradox Basin, Co, Usa, Sarah Lynn Evans

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation presents three studies that investigate extension in the Southern Snake Range (SSR) metamorphic core complex (MCC) of east-central Nevada and a thermal anomaly associated with the Gypsum Valley salt wall (GVSW) of southwestern Colorado. Low temperature thermochronologic studies using the (U-Th)/He system have been applied in numerous geologic settings to understand erosional and tectonic denudation processes. Two of the studies presented use (U-Th)/He thermochronology, combined with other techniques, to investigate the extensional history of the SSR and the extent of the GVSW thermal anomaly. Both of these studies present novel methods for understanding the thermal histories of the …

Security Threats From Uas And Its Mitigation Through Detection And Tracking, Sai Ram Ganti

UNLV Theses, Dissertations, Professional Papers, and Capstones

Unmanned Aerial Systems (UAS) are being used commonly for surveillance, providing valuable video data and reducing risk for humans wherever applicable. The cost of small UAS can range from as low as $30 to high as $5000, which makes it affordable by everyone. Most of the UAS are equipped with a camera which results in activities like disruption of privacy or capturing sensitive data. This research is aimed at developing a system which can detect and identify a drone and apply some counter measures to stop its functions or make it go away. The air traffic will increase significantly in …

Differences In Perceived Importance Of Preventative Services And Healthcare Provider Trust Among Hispanics, Jonathan James Gore

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Hispanic population varies greatly in their risk factors, health outcomes and access to care by country of origin, level of education and language dominance (Vega & Amaro, 1994) (Fiscella, Franks, Doescher, & Saver, 2002b). The differences within the Hispanic population also extend to their knowledge and attitudes toward health choices and maintenance, where they receive their health information, and what they access to meet their health care needs. Subpopulations within the Hispanic community as defined by language dominance and nativity must be understood as separate and distinct so that the health needs of each can be adequately addressed. The …

Top-K Nodes Identification In Big Networks Based On Topology And Activity Analysis, Sweta Gurung

UNLV Theses, Dissertations, Professional Papers, and Capstones

Graphs and Networks have been the most researched topics with applications ranging from theoretical to practical fields, such as social media, genetics, and education. In many competitive environments, the most productive activities may be interacting with high-profile people, reading a much-cited article, or researching a wide range of fields such as the study on highly connected proteins. This thesis proposes two methods to deal with top-K nodes identification: centrality-based and activity-based methods for identifying top-K nodes. The first method is based on the topological structure of the network and uses the centrality measure called Katz Centrality; a path based ranking …

Comparing The Effects Of Two Utility Value Interventions On Graduate Students' Interest, Performance, And Perceptions Of Utility Value, Ivan Vladimirov Ivanov

UNLV Theses, Dissertations, Professional Papers, and Capstones

The present study compares the immediate and delayed effects of teacher- vs. student-generated utility value interventions on students' interest, performance, and perceptions of utility value. In addition, it examines whether sense of autonomy mediates the relationship between type of utility value intervention and performance. The study is grounded in self-determination theory and expectancy-value theory and adopts a 3x3 mixed model design, with random assignment of participants to two relevance instruction conditions and a control condition.

Findings suggest that the teacher-generated utility value intervention was more effective than the student-generated utility value intervention and the control condition in terms of increased …

Effects Of Hydraulic Connections On Unsaturated Flow In Dual-Permeability Media, Jeevan Jayakody

UNLV Theses, Dissertations, Professional Papers, and Capstones

A geological medium that exhibits two distinct types of flow is known as dual-permeability medium. Unconsolidated deposits composed of coarse (> 2 mm diameter) clasts (gravel, talus, rockslide debris), engineered systems (heap leach piles, capillary barriers, rock fill), and mine/construction waste fall into this category. The large inter-clast pores that are characteristic of this type of media will drain at near zero matric potentials constraining flow to the interiors of porous clasts and/or the clast surfaces. In either case, water must pass through hydraulic bridges (porous contacts and/or pendular water) that form physical connections between neighboring clasts. Therefore, properties of …

A Study On Automated Process For Extracting White Blood Cellular Data From Microscopic Digital Injured Skeletal Muscle Images, Bibek Karki

UNLV Theses, Dissertations, Professional Papers, and Capstones

Skeletal muscle injury is one of the common injuries caused by high-intensity sports activities, military related works, and natural disasters. In order to discover better therapies, it is important to study muscle regeneration process. Muscle regeneration process tracking is the act of monitoring injured tissue section over time, noting white blood cell behavior and cell-fiber relations. A large number of microscopic images are taken for tracking muscle regeneration process over multiple time instances. Currently, manual approach is widely used to analyze a microscopic image of muscle cross section, which is time consuming, tedious and buggy.

Automation of this research methodology …

Inner Experience And Self-Ratings Of Inner Speaking, Jason Michael Kelsey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Questionnaires are often used as measures of inner experience. This study questions the adequacy of such measures, using inner speech as an example. We compared two questionnaire measures of inner speaking to each other and to inner experience as apprehended by Descriptive Experience Sampling (DES, a naturalistic, high fidelity method of exploring inner experience). Undergraduate volunteers (N = 260) took two questionnaires designed to measure inner speaking: the Self-Talk Scale (STS) and the Nevada Inner Experience Questionnaire (NIEQ). A subset of these (N = 16) participated in DES to investigate their inner speaking with fidelity. Scores on the NIEQ and …

Water Balance And Moisture Dynamics Of An Arid And Semi-Arid Soil: A Weighing Lysimeter And Field Study, Jeremy E. Koonce

UNLV Theses, Dissertations, Professional Papers, and Capstones

Semi-arid and arid environments are characterized by low precipitation and high evapotranspiration (ET), leaving little water available for discharge into surface water bodies and groundwater recharge. For these water-limited environments, understanding the relationships between precipitation, ET, and soil moisture is critical. These relationships not only affect water resources in these increasingly populated regions but are also necessary to predict the impact of climate change on semi-arid and arid ecosystems.

The overall goal of this dissertation was to shed light on the quantitative relationships between precipitation, evaporation, ET and soil moisture dynamics in an arid and a semi-arid environment. A three-step …

Algorithms For Monotone Paths With Visibility Properties, Bikash Lama Bamjan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Constructing collision-free paths in Euclidean space is a well-known problem in computational geometry having applications in many fields that include robotics, VLSI, and covert surveillance. In this thesis, we investigate the development of efficient algorithms for constructing a collision-free path that satisfies directional and visibility constraints. We present algorithms for constructing monotone collision-free paths that tend to maximize the visibility of the boundary of obstacles. We also present implementation of some monotone path planning algorithms in Java Programming Language.

A Case Study: Students' Mathematics-Related Beliefs From Integrated Stem Model-Eliciting Activities, Cathrine Maiorca

UNLV Theses, Dissertations, Professional Papers, and Capstones

This case study examines the mathematics-related beliefs of fourth and fifth grade students who participated in an after-school integrated science, technology, engineering and mathematics (STEM) program where participants completed four Model-Eliciting Activities. The research questions addressed by this study are, What is the nature of the change in mathematics-related beliefs of students who participate in an after-school MEA program? In particular, what is the difference, if any, of the nature of the change in beliefs across varying ability levels? The framework used to describe these beliefs was developed by Kloosterman and includes beliefs about the nature of mathematics and mathematics …

Efficient Algorithms For Clustering Polygonal Obstacles, Sabbir Kumar Manandhar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clustering a set of points in Euclidean space is a well-known problem having applications in pattern recognition, document image analysis, big-data analytics, and robotics. While there are a lot of research publications for clustering point objects, only a few articles have been reported for clustering a given distribution of obstacles. In this thesis we examine the development of efficient algorithms for clustering a given set of convex obstacles in the 2D plane. One of the methods presented in this work uses a Voronoi diagram to extract obstacle clusters. We also consider the implementation issues of point/obstacle clustering algorithms.

Creating A Dynamic, Multi-Purpose Correction For Multiple Geometries And Field Sizes To Account For Off-Axis And Asymmetric Backscatter With Varian Portal Dosimetry, Remy Manigold

UNLV Theses, Dissertations, Professional Papers, and Capstones

Intensity modulated radiation therapy and volumetric modulated arc therapy are increasingly common in radiation therapy due to their benefits of target conformity and normal tissue sparing. Due to the complexities of plan delivery and the precision required, the dose delivered must be accurately measured for quality assurance (QA). One of the most efficient ways to perform patient-specific QA when using clinical linear accelerators (linac) is to use an electronic portal imaging device (EPID). Amorphous silicon (aSi) Electronic Portal Imaging Devices (EPIDs) are attached to the linac and can provide real-time feedback with spatial resolution on the order of sub-millimeter pixel …

Development Of Solar Experiments With Remote Laboratory Capability For Engineering Education Of The Future, Otto Kyle Neidert

UNLV Theses, Dissertations, Professional Papers, and Capstones

Educating future engineers will be handled differently as this modern society has various methods of doing so and a plethora of knowledge to pursue. The availability of computers and internet has changed many things. A subject that is relevant in today’s world but not common to most people and some engineers is solar energy. As part of a grant from the National Science Foundation that was awarded to Louisiana State University (LSU), Florida State University (FSU), and the University of Nevada, Las Vegas (UNLV), the UNLV Center for Energy Research partnered with them to create solar application based learning modules. …

Tearing Up The Tallgrass, Brett Salsbury

UNLV Theses, Dissertations, Professional Papers, and Capstones

This creative thesis project is a culmination of the Master of Fine Arts in Creative Writing degree at UNLV. The thesis—currently titled Tearing up the Tallgrass—was composed entirely during my graduate semesters at UNLV. As a book of poetry, it explores the dynamics of humans in nature, white privilege, objectivity, fact- and myth-making, and artistic practice. Written under the supervision of Claudia Keelan (committee chair) and Donald Revell (committee member), my committee further includes P. Jane Hafen (English) and Pierre Lienard (Anthropology). Their disparate subject and genre interests are meant to diversify the feedback received during this project’s composition. Some …

Changes In Teachers' Constructivist Beliefs And Practices From Preservice To Inservice Teaching: A Mixed Methods Approach, Christina Joan Santoyo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Teacher candidates’ development into novice teachers is a social process that depends on their teaching context as well as the mentors who help them through the process. Viewed through the lens of social identity development theory and mentoring theory, this study used an embedded, mixed methods design to understand how and to what extent six Alternative Route to Licensure teacher candidates’ beliefs and practices differed from preservice to inservice teaching. Mixed-methods data were collected using observation, semi-structured interviews, and partial interval recording. The six participants included secondary math, English, science, and social studies preservice-turned-novice teachers. In order to understand the …

Parallel Static Object Detection, Tirambad Shiwakoti

UNLV Theses, Dissertations, Professional Papers, and Capstones

The need for parallelism is growing with the broadening of computing in the real world where computing is an integral part of any field. In the early days of computing, adding transistors to the CPU could solve computation complexity. This is not the case now, where we can no longer advance the hardware capabilities at the pace of the advancement of computing problems. One of the fields which is intensive in computation is image processing. If it were just for one frame of an image, we could cope with the computation overhead. When the need is to compute video frames, …

Interrelationships Among Teacher Self-Efficacy, Collective Teacher Efficacy, And Teachers’ Pedagogical Content Knowledge, Qingmin Shi

UNLV Theses, Dissertations, Professional Papers, and Capstones

A teacher’s self and collective efficacies are assumed to be related to his or her teaching and student learning in a specific content area. His or her pedagogical content knowledge in the subject content area is also assumed to shape his or her teaching practice. In addition, the quality of one’s teaching is influenced by the context in which teaching is situated. However, the relationships among teacher self-efficacy, collective teacher efficacy, and pedagogical content knowledge situated in individualist and collectivist contexts of teaching mathematics have not been empirically examined adequately. Through the lens of social cognitive theory on teacher efficacy, …

Causes Of Change Orders And Its Impact On Road Maintenance Contracts, Kabindra Kumar Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Change orders (CO) commonly generate cost-growth, schedule-growth or both, in construction as well as in maintenance contracts. Literature reviews revealed that the causes and impact of CO on new construction contracts had been comprehensively studied, but the causes and impact of CO in maintenance contracts remained neglected. This study collected CO data on road maintenance contracts to determine the amount of CO and the most frequent and high-risk road maintenance activities that had CO. A Delphi study was conducted with 33 maintenance engineers from the state Department of Transportation (DOT) to identify causes of CO and its impact on cost …

Synthesis And Characterization Of Graphene, Ashok Em Sudhakar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Graphene is an important nanoscale material with unique electronic and optical properties. Due to its many potential applications, grapheme was the subject of a Nobel Prize in physics 2010; Andre Geim and Kostya Novoselov of Manchester University received the Nobel Prize for demonstrating the ability to create single atom thick graphene layers from bulk graphite. Since then, many alternative synthesis techniques and device applications of graphene have been explored. An important and unique property of graphene is its excellent thermal properties. Graphene has a two dimensional structure and the thermal properties are significantly different than three dimensional bulk materials. Using …

Mining Unstructured Log Messages For Security Threat Detection, Candace Suh-Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

As computers become larger, more powerful, and more connected, many challenges arise in implementing and maintaining a secure computing environment. Some of the challenges come from the exponential increase of unstructured messages generated by the computer systems and applications. Although these data contain a wealth of information that is useful for advanced threat detection and prediction for future anomalies, the sheer volume, variety, and complexity of data make it difficult for even well-trained analysts to extract the right information. While conventional SIEM (Security Information and Event Management) tools provide some capability to collect, correlate, and detect certain events from structured …

Impacts To Phytoplankton After The Establishment Of Quagga Mussels In Lake Mead, Nevada, Warren Bruce Turkett

UNLV Theses, Dissertations, Professional Papers, and Capstones

Quagga mussels (Dreissena rostriformis bugensis) are an invasive species that were discovered in Lake Mead in January of 2007, and rapidly spread throughout the lake. Quagga mussels are about the size of a fingernail, but are known to clog pipes, damage infrastructure and alter ecosystems. In large numbers, mussels can have a dramatic impact on an ecosystem by reducing the phytoplankton and potentially increasing toxin producing cyanobacteria. This research analyzed data collected from three separate basins in Lake Mead to determine if water quality characteristics that are commonly impacted by invasive mussels have changed. Transparency, chlorophyll-a, phytoplankton and zooplankton samples …

An Empirical Study On The Impact Of C++ Lambdas And Programmer Experience, Phillip Merlin Uesbeck

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lambda functions have become prevalent in mainstream programming languages, as they are increasingly introduced to widely used object oriented programming languages such as Java and C++. Some in the scientific literature argue that this feature increases programmer productivity, ease of reading, and makes parallel programming easier. Others are less convinced, citing concerns that the use of lambdas makes debugging harder. This thesis describes the design, execution and results of an experiment to test the impact of using lambda functions compared to the iterator design pattern for iteration tasks, as a first step

in evaluating these claims. The approach is a …

Eight Steps To Weight Loss: Development Of An Evidence-Based Collaborative Provider-Patient Workbook For Overweight Or Obese Adults, Katherine Ann Wagner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite decades of effort on the part of health care providers and policy makers to reduce the prevalence of obesity, the prevalence of obesity in the United States remains high (CDC, 2015). In the adult population ages 20 years of age and older, 35.7% are considered obese. The annual medical costs for people who are obese are $1,429 higher than people of a healthy weight (CDC, 2013). Obesity increases the risk for chronic health conditions such as hypertension, type 2 diabetes, hypercholesterolemia, coronary heart disease, stroke, asthma, arthritis, and cancer (Hammond & Levine, 2010). Over-weight and obesity are the main …

Strategic Molecular Design To Engineer The Electron Affinity Of Self-Assembling Organic Semiconductors, Kelly Nicole Zaugg

UNLV Theses, Dissertations, Professional Papers, and Capstones

Development of electron-accepting (n-type) semiconductors used in organic photovoltaic cells and field effect transistors has been an area of research with less advancement compared to their electron-donating (p-type) counterparts. Currently, the highest performing n-type semiconductor is a fullerene-based derivative (PCBM) with a favorable ELUMO of -4.08 eV. However, PCBM has limited absorption in the visible region and fixed electron affinity. This work focuses on the development of self-assembling n-type materials with controllable electronic properties by strategically lowering ELUMO to a level comparable to PCBM. Molecular design follows an acceptor-acceptor'-acceptor (A-A'-A) configuration; with A being two 2,3-dioctyloxyphenazine substituents connected to A’ …

Innovative Fiber Optic/Thin Film Photovoltaic Systems: Adequately Distributing Daylight While Harvesting Energy, Sean Steven Zurko

UNLV Theses, Dissertations, Professional Papers, and Capstones

On any given year, Las Vegas will be exposed to an average of 85% sunlight during typical daylight hours, while averaging seven peak hours a day. That alone makes Las Vegas a prime candidate for renewable solar energy systems (Solar Direct, 2016). By implementing fiber optics into office buildings in conjunction with thin-film photovoltaics, interior spaces have the potential to be adequately illuminated while simultaneously harvesting electricity. The study will be conducted through analysis and experimental field research with the intent of generating physical data, demonstrating that a hybrid fiber optic - photovoltaic system can at minimum match recommended foot-candle …

Formulation And Characterization Of An Antimicrobial Coating Containing Nisin For Large Scale Food Package Converting Processes, Michele Christine Perna

All Dissertations

This research consisted of formulating an antimicrobial coating containing Nisaplin® intended for large scale production and inhibition of spoilage microorganisms. Secondly, the coating formulated was applied to a flexible film surface using two trials (gravure and flexography) commonly used in large scale food package coating or printing processes. In addition, diffusion and mass transfer theory was applied to discuss the many complications of predicting nisin diffusion or release from a coated material for antimicrobial food packaging applications.

Previous work conducted by predecessors, produced an antimicrobial coating formulation using a 70/30 Methylcellulose/Hydroxypropyl methylcellulose base (MC/HPMC). Some disadvantages of this coating included …

Defect Assisted Growth Of Copper-Silicide Nanostructures On Si(100) And Si(111), Endu Sekhar Srinadhu

All Dissertations

As the dimensions of the smallest feature on the integrated circuit has minia-turized into the range of tens of nanometers, patterning of highly ordered nanos-tructures with tunable size and shape in large scale on the surface of substrate is highly demanding and increasingly challenges the limits of nanolithography. To over-come the conventional lithographic limitations, self assembled methods have been explored. While strain driven self assembly is widely viewed as a promising technique for patterning at the nanoscale, to follow this approach and create structures in a desired manner, a reliable means to engineer and characterize the shape and sizes of …

Towards The Enhancement Of A Critical Cultural Paradigm In Health Communication: An Examination Of The Impact Of Paradigmatic Structures, Laura Elizabeth Arneson

Theses and Dissertations

In the field of Communication there are a wide variety of ways in which scholars can utilize theories to serve as epistemological frameworks in order to examine sociological structures. In this thesis, the subfield of Health Communication will be examined through a positivistic and critical cultural studies paradigm. This work will then examine underlying assumptions related to theoretical approaches in health communication.

With the primary argument of this work being that the dominant approaches in Healthcare Communication have been primarily rooted in positivism, this research study will attempt to show how this assumption continues to extend even into new digital …

Increasing Solubility Of Active Pharmaceutical Ingredients In Topical Creams Using Soluplus®, Roni Balzam

Graduate Theses/Dissertations

More than 40% of new chemicals developed in the pharmaceutical industry have poor solubility in aqueous solutions. Active Pharmaceutical ingredients (API) cannot reach their molecular targets in the body if the drug remains undissolved in the gastrointestinal system. One way to approach this problem is by using solubilizing agents. One such agent is a thermo-responsive, tri-block co-polymer which is marketed as “Soluplus®" (SP) by BASF Corporation. A part of this project is to thoroughly characterize various phase properties of SP such as cloud points and gel points temperatures. In current application, SP was incorporated into the creams formulations as an …