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2017

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Articles 841 - 870 of 12521

Full-Text Articles in Physical Sciences and Mathematics

Understanding Cigarette Butt Littering Behavior On A Public Beach: A Case Study Of Jekyll Island, Maranda R. Miller, Mark E. Burbach Dec 2017

Understanding Cigarette Butt Littering Behavior On A Public Beach: A Case Study Of Jekyll Island, Maranda R. Miller, Mark E. Burbach

Conservation and Survey Division

Conservation of natural resources and promotion of family-friendly tourism activities are vital to Jekyll Island. As it is stated in the Jekyll Island Authority (JIA) Master Plan “Jekyll Island is a unique, state-owned barrier island that balances conserving and preserving natural, historic, and cultural resources with providing accessible, affordable recreation, vacation, and education opportunities for the people of Georgia and beyond” (Jekyll Island Authority, 2014b, p. 4). The JIA has reported approximately 1 million people visit the island annually (Jekyll Island Authority, 2015). As such, tourism is instrumental to Jekyll Island’s economy, and that tourism contributes to the overall economy …


Eco-Justice Reformation: Re-Imagining Ecumenical Witness In The Context Of Climate Injustice, George Zachariah Dec 2017

Eco-Justice Reformation: Re-Imagining Ecumenical Witness In The Context Of Climate Injustice, George Zachariah

Consensus

No abstract provided.


A Cluster Analysis Of Challenging Behaviors In Autism Spectrum Disorder, Elizabeth Stevens, Abigail Atchison, Laura Stevens, Esther Hong, Doreen Granpeesheh, Dennis Dixon, Erik J. Linstead Dec 2017

A Cluster Analysis Of Challenging Behaviors In Autism Spectrum Disorder, Elizabeth Stevens, Abigail Atchison, Laura Stevens, Esther Hong, Doreen Granpeesheh, Dennis Dixon, Erik J. Linstead

Mathematics, Physics, and Computer Science Faculty Articles and Research

We apply cluster analysis to a sample of 2,116 children with Autism Spectrum Disorder in order to identify patterns of challenging behaviors observed in home and centerbased clinical settings. The largest study of this type to date, and the first to employ machine learning, our results indicate that while the presence of multiple challenging behaviors is common, in most cases a dominant behavior emerges. Furthermore, the trend is also observed when we train our cluster models on the male and female samples separately. This work provides a basis for future studies to understand the relationship of challenging behavior profiles to …


Neutrosophic Hough Transform, Florentin Smarandache, Umit Budak, Yanhui Guo, Abdulkadir Sengur Dec 2017

Neutrosophic Hough Transform, Florentin Smarandache, Umit Budak, Yanhui Guo, Abdulkadir Sengur

Branch Mathematics and Statistics Faculty and Staff Publications

Hough transform (HT) is a useful tool for both pattern recognition and image processing communities. In the view of pattern recognition, it can extract unique features for description of various shapes, such as lines, circles, ellipses, and etc. In the view of image processing, a dozen of applications can be handled with HT, such as lane detection for autonomous cars, blood cell detection in microscope images, and so on. As HT is a straight forward shape detector in a given image, its shape detection ability is low in noisy images. To alleviate its weakness on noisy images and improve its …


A Test Driven Approach To Develop Web-Based Machine Learning Applications, Armin Esmaeilzadeh Dec 2017

A Test Driven Approach To Develop Web-Based Machine Learning Applications, Armin Esmaeilzadeh

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this thesis is to propose the design and architecture of a testable, scalable, and ef-cient web-based application that models and implements machine learning applications in cancer prediction. There are various components that form the architecture of our web-based application including server, database, programming language, web framework, and front-end design. There are also other factors associated with our application such as testability, scalability, performance, and design pattern. Our main focus in this thesis is on the testability of the system while consid- ering the importance of other factors as well.

The data set for our application is a …


Investigation Of Setting Time And Compressive Strength Of Ready-Mixed Concrete Blended With Returned Fresh Concrete, Negasi Niguse Gebremichael Dec 2017

Investigation Of Setting Time And Compressive Strength Of Ready-Mixed Concrete Blended With Returned Fresh Concrete, Negasi Niguse Gebremichael

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Center for Sustainable Transportation Infrastructure (CSTI), in its 2012 study, estimated that out of all the concrete leaving the plant, between 2% and 7% of concrete returns to the plant unused as a returned fresh concrete (RFC). Disposal of both the truck wash water and RFC is a growing concern for the industry. Most industry personnel contacted during the investigation, agree that reusing is superior to recycling of this substantial RFC economically and environmentally. This study will determine if the reuse of RFC in subsequent batches compromises the quality of newly blended concrete.

The effect of RFC on fresh …


Controlled Electrochemical Reduction Of Gold And Palladium Metal Precursors In Polyaniline, Nicole Goodwin Dec 2017

Controlled Electrochemical Reduction Of Gold And Palladium Metal Precursors In Polyaniline, Nicole Goodwin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Polyaniline (PANI) has been extensively studied due to its unique electrochemical properties. The conjugated polymer is conductive with high chemical stability below 100°C, mechanical strength, and large surface area. The applications of PANI have included chemical sensing, corrosion inhibition coatings, light emitting diode and as a substrate for metal composite catalysts. Both chemical and electrochemical methods have been developed and utilized in the synthesis of PANI/metal composites. The simultaneous reduction of aniline and metal precursor produces a composite of PANI encapsulated metal, reducing the active surface area available for catalysis. Alternatively, chemical reduction of the metal precursor into preformed PANI …


Average Cayley Genus For Groups With Two Generators Of Order Greater Than Two, Dawn Sturgeon Dec 2017

Average Cayley Genus For Groups With Two Generators Of Order Greater Than Two, Dawn Sturgeon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Determining the orientable surfaces on which a particular graph may be imbedded is a basic problem in the area of topological graph theory. We look at groups modeled by Cayley graphs. Imbedding Cayley graphs with symmetry is done using Cayley maps. It is of interest to find the average Cayley genus for a particular group and generating set for the group. We consider the group known as the generalized quaternions with generating set ∆, where ∆ contains two generators with order greater than two. We find a formula for the average Cayley genus of the generalized quaternions. Moreover, we determine …


Lock-Free Self-Adjusting Binary Search Tree, Sachiko Sueki Dec 2017

Lock-Free Self-Adjusting Binary Search Tree, Sachiko Sueki

UNLV Theses, Dissertations, Professional Papers, and Capstones

A binary search tree (BST) is a fundamental data structure for maintaining data in a way to allow fast search. As multi-core processors are widely used nowadays, such data structures require the ability to handle concurrent accesses to exploit the concurrent hardware. There are several algorithms on lock-based as well as lock-free BST with and without self-balancing. On the other hand, only a few reports can be found on lock-based self-adjusting BST. To the best of our knowledge, there are no algorithms for lock-free self-adjusting BST. Lock-free guarantees overall progress even if some processes fail, whereas lock-based algorithms fail to …


The Transformation Of American Federalism, 1848-1912, Lance Sorenson Dec 2017

The Transformation Of American Federalism, 1848-1912, Lance Sorenson

UNLV Theses, Dissertations, Professional Papers, and Capstones

United States expansion following the Mexican-American War served as the catalyst for a reinvention of American Federalism. While much of the historiography traces the accretion of sovereign power in the national government to events caused by the divisions between northern states and southern states, there is an important and understudied East to West component of the process by which sovereign boundaries changed. The American West is a legal space where the hazily defined and capacious concept of federalism received fuller form and clearer definition. During the late nineteenth century and first few years of the twentieth century, the United States …


Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle Dec 2017

Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle

UNLV Theses, Dissertations, Professional Papers, and Capstones

The disease chytridiomycosis, caused by the aquatic fungal pathogen Batrachochytrium dendrobatidis (Bd), has emerged as a major contributing factor for worldwide amphibian declines. Although relatively recently described, the impacts from the disease this pathogen causes have been definitively tied to amphibian declines, including some that occurred decades ago. In some cases, declines of individual species occurred with little documentation and are thus poorly understood. The relict leopard frog (Rana onca = Lithobates onca) has experienced such a decline and by the latter part of the 20th century only occurred in two general areas in southern Nevada. Recent research has found …


Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts Dec 2017

Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts

Theses and Dissertations

Snowmelt river systems exhibit seasonal fluxes in water chemistry, potentially affecting the water supply of one-sixth of the worlds population. In this study, we examined water chemistry of the upper Provo River, northern Utah, which supplies water to over two million people along the urban Wasatch Front. Seasonal changes in water chemistry were characterized by analyzing discharge and dissolved organic carbon (DOC) with dissolved trace metal and cation concentrations (La, Pb, Cu, Al, Be, Sr and K) over three consecutive water years 20142016, with intensive sampling during snowmelt runoff. To better understand links between metal movement and DOC, we sampled …


Capacity Of Human Immunodeficiency Virus Targeting Chimeric Antigen Receptor T Cells To Eliminate Follicular Dendritic Cells Bearing Human Immunodeficiency Virus Immune Complexes, Matthew T. Ollerton Dec 2017

Capacity Of Human Immunodeficiency Virus Targeting Chimeric Antigen Receptor T Cells To Eliminate Follicular Dendritic Cells Bearing Human Immunodeficiency Virus Immune Complexes, Matthew T. Ollerton

Theses and Dissertations

An important obstacle to a functional cure for HIV/AIDS is the persistence of viral reservoirs found throughout the body in various cells and tissues. Reservoirs can be latently infected cells, or in the case of follicular dendritic cells (FDC), non-infected cells that trap infectious virus on their surface through immune complexes (HIV-IC). Although several strategies have been employed to target and eliminate viral reservoirs, they are short-lived and ineffective. In an attempt to provide a long-term approach, chimeric antigen receptor T (CAR-T) cells were designed to eliminate native HIV on FDCs. Although effective at eliminating HIV-infected cells, and halting spreading …


Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts Dec 2017

Dissolved Organic Carbon And Dissolved Metal Pulses During Snowmelt Runoff In The Upper Provo River Watershed, Utah, Usa, Hannah Nicole Checketts

Theses and Dissertations

Snowmelt river systems exhibit seasonal fluxes in water chemistry, potentially affecting the water supply of one-sixth of the worlds population. In this study, we examined water chemistry of the upper Provo River, northern Utah, which supplies water to over two million people along the urban Wasatch Front. Seasonal changes in water chemistry were characterized by analyzing discharge and dissolved organic carbon (DOC) with dissolved trace metal and cation concentrations (La, Pb, Cu, Al, Be, Sr and K) over three consecutive water years 2014”2016, with intensive sampling during snowmelt runoff. To better understand links between metal movement and DOC, we sampled …


On The Progenitor Of Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier Dec 2017

On The Progenitor Of Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier

Physics and Astronomy Faculty Publications and Presentations

On 2017 August 17 the merger of two compact objects with masses consistent with two neutron stars was discovered through gravitational-wave (GW170817), gamma-ray (GRB 170817A), and optical (SSS17a/AT 2017gfo) observations. The optical source was associated with the early-type galaxy NGC 4993 at a distance of just ∼40 Mpc, consistent with the gravitational-wave measurement, and the merger was localized to be at a projected distance of ∼2 kpc away from the galaxy's center. We use this minimal set of facts and the mass posteriors of the two neutron stars to derive the first constraints on the progenitor of GW170817 at the …


Acoustic Intensity Of Narrowband Signals In Free-Field Environments, Kelli Fredrickson Succo Dec 2017

Acoustic Intensity Of Narrowband Signals In Free-Field Environments, Kelli Fredrickson Succo

Theses and Dissertations

The phase and amplitude gradient estimator (PAGE) method has proven successful in improving the accuracy of measured energy quantities over the p-p method, which has traditionally been used, in several applications. One advantage of the PAGE method is the use of phase unwrapping, which allows for increased measurement bandwidth above the spatial Nyquist frequency. However, phase unwrapping works best for broadband sources in free-field environments with high coherence. Narrowband sources often do not have coherent phase information over a sufficient bandwidth for a phase unwrapping algorithm to unwrap properly. In fact, phase unwrapping processing can cause significant error when there …


Synthesis Of Actinide Materials For The Study Of Basic Actinide Science And Rapid Separation Of Fission Products, Jacquelyn M. Dorhout Dec 2017

Synthesis Of Actinide Materials For The Study Of Basic Actinide Science And Rapid Separation Of Fission Products, Jacquelyn M. Dorhout

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation covers several distinct projects relating to the fields of nuclear forensics and basic actinide science. Post-detonation nuclear forensics, in particular, the study of fission products resulting from a nuclear device to determine device attributes and information, often depends on the comparison of fission products to a library of known ratios. The expansion of this library is imperative as technology advances. Rapid separation of fission products from a target material, without the need to dissolve the target, is an important technique to develop to improve the library and provide a means to develop samples and standards for testing separations. …


The Impact Of Economic Recession On The Health Of Adult Nevadans, Ariana Goertz Dec 2017

The Impact Of Economic Recession On The Health Of Adult Nevadans, Ariana Goertz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recessions are generally considered to cause negative consequences, but recent studies have provided evidence that some health outcomes improve as the economy deteriorates. The relationship between economic downfalls and health is not straightforward; it is important to look at how health has been impacted in one of the areas hit hardest by the recession. Las Vegas, Nevada was previously considered recession-proof, seemingly unaffected by previous economic downturns exhibited by the rest of the country. However, during the Great Recession of 2007-2009, Las Vegas led the country in highest rates of unemployment and foreclosures. This was quite a collapse for a …


Using Two Simulation Tools To Teach Concepts In Introductory Astronomy: A Design-Based Research Approach, Pamela A. Maher Dec 2017

Using Two Simulation Tools To Teach Concepts In Introductory Astronomy: A Design-Based Research Approach, Pamela A. Maher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Technology in college classrooms has gone from being an enhancement to the learning experience to being something expected by both instructors and students. This design-based research investigation takes technology one step further, putting the tools used to teach directly in the hands of students. The study examined the affordances and constraints of two simulation tools for use in introductory astronomy courses. The variety of experiences participants had using two tools; a virtual reality headset and fulldome immersive planetarium simulation, to manipulate a lunar surface flyby were identified using a multi-method research approach with N = 67 participants. Participants were recruited …


Synthesis And Electrochemical Characterization Of Pani/Ni And Pani/Au/Ni Composites, Morgan Emily Pacini Dec 2017

Synthesis And Electrochemical Characterization Of Pani/Ni And Pani/Au/Ni Composites, Morgan Emily Pacini

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research is to show that the electrochemically controlled formation of monometallic and bimetallic catalysts in polyaniline (PANI) can directly influence the efficiency and reproducibility of the catalytic oxidation of methanol. PANI is a conductive polymer that provides a three-dimensional template for the metallic catalysts deposition at nitrogen sites. The controlled deposition of metallic species can be achieved using the normal oxidation/reduction cycles of PANI. The deposition of metallic species relies on anion precursors that are electrostatically bound by the polymer during the oxidation cycle. The precursor is reduced directly at the nitrogen sites in the polymer …


Effects Of Temperature On Growth And Molting In Blue Crabs (Callinectes Sapidus) And Lesser Blue Crabs (Callinectes Similis), Abigail Ann Kuhn Dec 2017

Effects Of Temperature On Growth And Molting In Blue Crabs (Callinectes Sapidus) And Lesser Blue Crabs (Callinectes Similis), Abigail Ann Kuhn

Master's Theses

Temperature can exert impacts on many processes in ectotherms. With global temperatures rising due to climate change, many ectothermic species may exhibit changes in growth rates and size at maturity, and these changes can have population-level effects. Predicting responses of species to climate change will require not only knowledge of thermal tolerance limits, but also effects of temperature change on growth rates and other life history parameters. For arthropods that exhibit discontinuous growth (i.e., molting), this includes both intermolt period and growth per molt. Previous laboratory and field experiments suggest that temperature affects both intermolt period (IMP) and growth per …


Recommender Systems For Family History Source Discovery, Derrick James Brinton Dec 2017

Recommender Systems For Family History Source Discovery, Derrick James Brinton

Theses and Dissertations

As interest in family history research increases, greater numbers of amateurs are participating in genealogy. However, finding sources that provide useful information on individuals in genealogical research is often an overwhelming task, even for experts. Many tools assist genealogists in their work, including many computer-based systems. Prior to this work, recommender systems had not yet been applied to genealogy, though their ability to navigate patterns in large amounts of data holds great promise for the genealogical domain. We create the Family History Source Recommender System to mimic human behavior in locating sources of genealogical information. The recommender system is seeded …


Evaporated Aluminum Fluoride As A Barrier Layer To Retard Oxidation Of Aluminum Mirrors, Margaret Miles Dec 2017

Evaporated Aluminum Fluoride As A Barrier Layer To Retard Oxidation Of Aluminum Mirrors, Margaret Miles

Theses and Dissertations

The aluminum oxide growth rate for aluminum protected with 2.4 nm of aluminum fluoride has been determined. We show that a 2.4 nm aluminum fluoride layer does not prevent aluminum from oxidation but does significantly retard the oxide growth – decreasing the oxide layer thickness from 1 nm in less than an hour to 0.9 nm over 116 hours. Additionally, the optical constants for aluminum oxide growing under an aluminum fluoride barrier layer have been determined – showing an increase in absorption at high energies for Al2O3 forming at room temperature as compared to highly ordered Al …


Copper Mineralogy In The Oxide Zone Of The Lone Star Porphyry Copper Deposit, Eastern Arizona, Jeff G. Selck Dec 2017

Copper Mineralogy In The Oxide Zone Of The Lone Star Porphyry Copper Deposit, Eastern Arizona, Jeff G. Selck

Theses and Dissertations

The Lone Star porphyry copper deposit in the Safford District of southeastern Arizona was discovered in the late 1800's but never mined on a large scale. In addition to typical copper oxide species such as chrysocolla, the upper part of the deposit has zones of mineralization in which the chemical assays of core samples have higher amounts of copper than can be visually assigned to the observed copper-bearing minerals. The goal of this study is to identify the Cu-bearing minerals, which is crucial because the efficiency of the extraction processes is strongly dependent upon the mineralogy. Samples from seven cores …


Developing A Translational Ecology Workforce, Mark W. Schwarts, J. Kevin Hiers, Frank W. Davis, Gregg M. Garfin, Stephen T. Jackson, Adam J. Terando, Connie A. Woodhouse, Toni Lyn Morelli, Matthew A. Williamson, Mark W. Brunson Dec 2017

Developing A Translational Ecology Workforce, Mark W. Schwarts, J. Kevin Hiers, Frank W. Davis, Gregg M. Garfin, Stephen T. Jackson, Adam J. Terando, Connie A. Woodhouse, Toni Lyn Morelli, Matthew A. Williamson, Mark W. Brunson

Environment and Society Faculty Publications

We define a translational ecologist as a professional ecologist with diverse disciplinary expertise and skill sets, as well as a suitable personal disposition, who engages across social, professional, and disciplinary boundaries to partner with decision makers to achieve practical environmental solutions. Becoming a translational ecologist requires specific attention to obtaining critical non-scientific disciplinary breadth and skills that are not typically gained through graduate-level education. Here, we outline a need for individuals with broad training in interdisciplinary skills, use our personal experiences as a basis for assessing the types of interdisciplinary skills that would benefit potential translational ecologists, and present steps …


Spotsylvania County, Virginia Shoreline Inventory Report Summary Tables, Marcia Berman, Karinna Nunez, Tamia Rudnicky, Julie Bradshaw, Karen Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner Dec 2017

Spotsylvania County, Virginia Shoreline Inventory Report Summary Tables, Marcia Berman, Karinna Nunez, Tamia Rudnicky, Julie Bradshaw, Karen Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).


An Lntegrated Approach (Remote Sensing, Hydrogeology, Geotechnical, And Geoinformatics) To Assess And Monitor Fossil Aquifers And Associated Land Deformation Over The Arabian Peninsula, Abdullah Ghurmullah Saeed Othman Dec 2017

An Lntegrated Approach (Remote Sensing, Hydrogeology, Geotechnical, And Geoinformatics) To Assess And Monitor Fossil Aquifers And Associated Land Deformation Over The Arabian Peninsula, Abdullah Ghurmullah Saeed Othman

Dissertations

Deformational features such as subsidence, sinkholes, fissures, settling and cracks in buildings and structures, and earthquakes are being reported from many of the world’s arid lands, in areas where fossil aquifers are being excessively exploited. Using the Lower Mega Aquifer System (LMAS) in Arabia as a test site, I applied an integrated approach (remote sensing, geodesy, GIS, geology, hydrogeology, and geotechnical) to identify nature, intensity, spatial distribution, and factors controlling the observed deformation in the central (Al-Qassim and Ha'il regions; area: 16×10⁴ km²) and the northern (Wadi As-Sirhan Basin; area: ~10.9×10⁴ km²) Arabia. A four -fold approach was adopted to …


A Hybrid Parallel Approach To High-Performance Compression Of Big Genomic Files And In Compresso Data Processing, Sandino N. Vargas Pérez Dec 2017

A Hybrid Parallel Approach To High-Performance Compression Of Big Genomic Files And In Compresso Data Processing, Sandino N. Vargas Pérez

Dissertations

Due to the rapid development of high-throughput low cost Next-Generation Sequencing, genomic file transmission and storage is now one of the many Big Data challenges in computer science. Highly specialized compression techniques have been devised to tackle this issue, but sequential data compression has become increasingly inefficient and existing parallel algorithms suffer from poor scalability. Even the best available solutions can take hours to compress gigabytes of data, making the use of these techniques for large-scale genomics prohibitively expensive in terms of time and space complexity.

This dissertation responds to the aforementioned problem by presenting a novel hybrid parallel approach …


Ldentifying And Characterizing Cognitive Factors Significant To Practicing And Learning Meteorology, Peggy M. Mcneal Dec 2017

Ldentifying And Characterizing Cognitive Factors Significant To Practicing And Learning Meteorology, Peggy M. Mcneal

Dissertations

To see the world as a meteorologist, one must understand and interpret atmospheric processes through representations depicted on two-dimensional weather charts and maps that encode large amounts of spatial and numerical data. This is a cognitively demanding and spatially challenging task, especially for students with burgeoning levels of meteorology knowledge, who lack the expertise of practiced meteorologists that read such charts and maps with ease. With little prior work informing meteorology and meteorology education through a cognitive science lens, this study surveys the literature and follows models of discipline-based education and cognitive science research to identify the discrete intelligence factors …


Development Of Large-Area Gem Detectors For The Forward Muon Endcap Upgrade Of The Cms Experiment And Search For Sm Higgs Boson Decay In The H → Τ+Τ− → Μ+Μ−¯Νμνμ¯Ντντ Channel At √ S = 13 Tev, Vallary Shashikant Bhopatkar Dec 2017

Development Of Large-Area Gem Detectors For The Forward Muon Endcap Upgrade Of The Cms Experiment And Search For Sm Higgs Boson Decay In The H → Τ+Τ− → Μ+Μ−¯Νμνμ¯Ντντ Channel At √ S = 13 Tev, Vallary Shashikant Bhopatkar

Theses and Dissertations

Gas Electron Multiplier (GEM) technology is being considered for the forward muon upgrade of the Compact Muon Solenoid (CMS) experiment in Phase II of the CERN LHC. The first GEM Endcap (GE1/1) is going to be installed in the 1.5 <| η |< 2.2 region of the muon endcap mainly to control muon level-1 trigger rates after the second long LHC shutdown. A GE1/1 triple-GEM detector is read out by 3,072 radial strips with 453 µrad pitch arranged in eight η-sectors. A meter-long GE1/1 prototype-III was assembled at Florida Tech and tested in 20-120 GeV hadron beams at Fermilab using Ar/CO2 70:30 and the RD51 Scalable Readout System (SRS). Four GEM detectors with 2-D readout and an average measured azimuthal resolution of 36µrad provided precise reference tracks. Construction of this GE1/1 prototype-III detector and its performance in the test beam are described. Strip cluster parameters, detection efficiency, and spatial resolution are studied with position and high voltage scans. The plateau detection efficiency is [97.80 ± 0.2 (stat)]%. The azimuthal resolution is found to be [123.5 ± 1.6 (stat)] µrad when operating in the center of the efficiency plateau and using full pulse height information. The CMS upgrade design calls for readout electronics with binary hit output. When strip clusters are formed correspondingly without charge-weighting and with fixed hit thresholds, a position resolution of [136.8 ± 2.5 stat] µrad is measured, consistent with the expected resolution from strip-pitch/√ 12 = 131.3 µrad. The eight η-sectors of the detector show a similar response and performance. VFAT3 electronics are being considered for the readout system of GE1/1 detectors. The charge that is induced on the GE1/1 readout strips by minimum-ionizing particles is an important parameter that informs the design of the amplifier-shaper input stage of the VFAT3 chip. To estimate the input charge range for these electronics, the most probable value, mean value, and 99th percentile value of the Landau distribution of the charge induced on a single strip are measured and found to be 4 fC, 11 fC, and 115 fC, respectively. The Z/γ∗ → τ τ cross section in proton-proton collisions at √ s = 13 TeV is measured, using data recorded by the CMS experiment at the LHC during 2015 and corresponding to an integrated luminosity of 2.3 fb−1 . The product of the cross section and branching fraction is measured in the dimuon final state to be 1967 ± 121 (stat.) ± 92 (syst.) ± 37 (lumi.) pb, in agreement with the standard model expectation, computed at next-to-next-to-leading order accuracy in perturbative quantum chromodynamics. A search for Standard Model (SM) Higgs bosons decaying into pairs of tau leptons and then to two muons plus (anti)-neutrinos is performed using the data collected by the CMS detector in 2016 with 35.9 fb−1 of integrated luminosity. The upper limits on the cross section relative to SM prediction are calculated in three event categories with different jet multiplicities focusing on Higgs boson signal events produced via gluon-gluon fusion and vector boson fusion. A multivariate analysis with Boosted Decision Trees (BDT) is used to suppress the large Drell-Yan background. The di-tau mass is reconstructed using a Secondary-Vertex fit (SVFit) algorithm using a maximum likelihood approach. Experimental limits are presented in all three categories extracted from the maximum likelihood fit of reconstructed di-tau mass and the visible mass of the dimuon system. The signal strength for the combination of all three categories is estimated as -1.0 ± 1.7. The expected and observed upper limits with 95% CL is at 3.2 and 2.7, respectively, with respect to the SM cross section times branching fraction.