Digital Commons Network^™

Relativistic Astronomy. Ii. In-Flight Solution Of Motion And Test Of Special Relativity Light Aberration, Jin-Ping Zhu, Bing Zhang, Yuan-Pei Yang

Physics & Astronomy Faculty Research

The Breakthrough Starshot project aims to send centimeter-sized, gram-scale "StarChip" probes to Alpha Centauri at a speed of ~0.2 c. On the other hand, Zhang & Li recently proposed that transrelativistic cameras may be sent to any direction to study astronomical objects and test special relativity. To conduct such "relativistic astronomy," one needs to solve the motion of the probe in flight. We solve the motion of the probe (including the moving direction and the velocity) by comparing the positions of three or more point sources observed in the Earth rest frame and in the probe's comoving frame. When the …

The Environmental Impact And Formation Of Meals From The Pilot Year Of A Las Vegas Convention Food Rescue Program, Samantha To, Courtney Coughenour, Jennifer Pharr

Environmental & Global Health Faculty Research

Annually, millions of tonnes of leftover edible foods are sent to landfill. Not only does this harm the environment by increasing the release of greenhouse gases which contribute to climate change, but it poses a question of ethics given that nearly 16 million households are food insecure in the US, and hundreds of millions of people around the globe. The purpose of this study was to document the amount of food diverted from landfill in the pilot year of a convention food rescue program and to determine the amount of greenhouse gas (GHG) emissions avoided by the diversion of such …

Cave Temperature And Management Implications In Lehman Caves, Great Basin National Park, Usa, Stanka Šebela, Gretchen Baker, Barbara Luke

Civil and Environmental Engineering and Construction Faculty Research

Cave air temperature was measured at six locations in Lehman Caves (USA) for one year at hourly intervals. Lehman is a show cave in a national park, treasured for its geological and biological resources. The two monitoring locations that are off of the tour route and, also, relatively distant from the cave’s entrances displayed nearly constant air temperature during the year. The other four sites, along the tour route, show daily temperature variation as well as annual fluctuation. After visitation levels decreased in the autumn, cave temperatures lagged but eventually reached an equilibrium which demonstrates recovery in the quiet winter. …

Cosmology-Independent Estimate Of The Fraction Of Baryon Mass In The Igm From Fast Radio Burst Observations, Zhengxiang Li, He Gao, Jun-Jie Wei, Yuan-Pei Yang, Bing Zhang, Zong-Hong Zhu

Physics & Astronomy Faculty Research

The excessive dispersion measure (DM) of fast radio bursts (FRBs) has been proposed to be a powerful tool to study intergalactic medium (IGM) and to perform cosmography. One issue is that the fraction of baryons in the IGM, f IGM, is not properly constrained. Here, we propose a method of estimating f IGM using a putative sample of FRBs with the measurements of both DM and luminosity distance d L. The latter can be obtained if the FRB is associated with a distance indicator (e.g., a gamma-ray burst or a gravitational-wave event), or the redshift z of the FRB is …

On Peter Olen's Wilfrid Sellars And The Foundations Of Normativity, David Beisecker

Philosophy Faculty Research

All contributions included in the present issue were originally prepared for an “Author Meets Critics” session organized by Carl Sachs for the Eastern Division Meeting of the American Philosophical Association in Savannah, Georgia, on 5th January, 2018.

Pressure-Induced Phase Transition In 1,3,5-Triamino-2,4,6-Trinitrobenzene (Tatb), Brad A. Steele, Samantha M. Clarke, Matthew P. Kroonblawd, I-Feng W. Kuo, Philip F. Pagoria, Sergey N. Tkachev, Jesse S. Smith, Sorin Bastea, Laurence E. Fried, Joseph M. Zaug, Elissaios Stavrou, Oliver Tschauner

Geoscience Faculty Research

Determining the unreacted equation of state of 1,3, 5-triamino-2,4,6-trinitrobenzene (TATB) is challenging because it exhibits low crystal symmetry and low X-ray scattering strength. Here, we present the first high-pressure single-crystal X-ray diffraction (SXD) study of this material. Our SXD results reveal a previously unknown transition to a monoclinic phase above 4 GPa. No abrupt change of the volume occurs but the compressibility changes. Concomitant first principles evolutionary crystal structure prediction USPEX calculations confirm this transition and show that it involves a pressure-induced in-plane shift of the layers of TATB molecules with respect to the ambient-pressure phase.

Magnetic Borophenes From An Evolutionary Search, Meng-Hong Zhu, Xiao-Ji Weng, Guoying Gao, Shuai Dong, Ling-Fang Lin, Wei-Hua Wang, Qiang Zhu, Artem R. Oganov, Xiao Dong, Yongjun Tian, Xiang-Feng Zhou, Hui-Tian Wang

Physics & Astronomy Faculty Research

A computational methodology based on ab initio evolutionary algorithms and spin-polarized density functional theory was developed to predict two-dimensional magnetic materials. Its application to a model system borophene reveals an unexpected rich magnetism and polymorphism. A metastable borophene with nonzero thickness is an antiferromagnetic semiconductor from first-principles calculations, and can be further tuned into a half-metal by finite electron doping. In this borophene, the buckling and coupling among three atomic layers are not only responsible for magnetism, but also result in an out-of-plane negative Poisson's ratio under uniaxial tension, making it the first elemental material possessing auxetic and magnetic properties …

Thermotropic Liquid-Crystalline And Light-Emitting Properties Of Poly(Pyridinium) Salts Containing Various Diamine Connectors And Hydrophilic Macrocounterions, Tae Soo Jo, Haesook Han, Pradip K. Bhowmik, Benoît Heinrich, Bertrand Donnio

Chemistry and Biochemistry Faculty Research

A set of poly(pyridinium) salts containing various diamine moieties, as molecular connectors, and poly(ethyleneglycol)-4-nonylphenyl-3-sulfopropyl ether, thereafter referred to as “Macroion”, as the hydrophilic counterion, were prepared by metathesis reaction from the respective precursory tosylated poly(pyridinium)s in methanol. The structure of these ionic polymers was established by spectroscopy and chromatography techniques. The shape-persistent ionic poly(pyridinium) materials, inserting rigid or semi-rigid diamine spacers, display thermotropic liquid-crystalline properties from room-temperature up to their isotropization (in the temperature range around 160–200 °C). The nature of the LC phases is lamellar in both cases as identified by the combination of various complementary experimental techniques including …

College Of Engineering Senior Design Competition Spring 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

On The Time-Frequency Downward Drifting Of Repeating Fast Radio Bursts, Weiyang Wang, Bing Zhang, Xuelei Chen, Renxin Xu

Physics & Astronomy Faculty Research

The newly discovered second repeating fast radio burst (FRB) source, FRB 180814.J0422+73, was reported to exhibit a time–frequency downward drifting pattern, which is also seen in the first repeater FRB 121102. We propose a generic geometrical model to account for the observed downward drifting of sub-pulse frequency, within the framework of coherent curvature radiation by bunches of electron–positron pairs in the magnetosphere of a neutron star (NS). A sudden trigger event excites these coherent bunches of charged particles, which stream outward along open field lines. As the field lines sweep across the line of sight, the bunches seen later travel …

Problems Faced By Secondary Technology Education Novice And Veteran Teachers, Sally E. Arnett-Hartwick, John Cannon

Journal of Research in Technical Careers

The purpose of this study was to examine the challenges faced by secondary technology education (TE) teachers in Illinois. Specifically, the study sought to identify and categorize a list of challenges encountered during their first years in the TE profession as well as challenges that veteran TE teachers are facing in their current teaching assignment. Seventy-three TE teachers completed an online questionnaire. Twenty-six challenges were identified and of the top five challenges, only three, equipment, funding, and understanding what TE is were identified as a continuous challenge at each career stage. Knowing the challenges identified by TE teachers at different …

Developing Stem Identity Of Nez Perce Students: Identifying Entry-Level Competencies For Forestry And Fire Management, Raymond A. Dixon, Karla Eitel, Yudi Zhu

Journal of Research in Technical Careers

The purpose of this study was to identify the competencies that are required for entry-level forestry and fire management technicians. The strategy is a part of a larger goal to develop the STEM identity of Nez Perce students through the integration of relevant competencies in middle and high school curriculums. The DACUM process was used. Through this groupware process, nine experts from the Nez Perce Natural Resources produced a competency profile consisting of 12 duties and 79 tasks, along with general knowledge and skills, attitudes, tools, and future trends. Findings indicate that the experts view relevant cultural competencies as central …

Model-Free Implied Volatility Under Jump-Diffusion Models, Seungmook Choi, Hongtao Yang

Department of Finance Faculty Research

The model-free implied volatility (MFIVol) is intended to measure the variability of underlying asset price on which options are written. Analytically, however, it does not measure exactly the variability under jump diffusion. Our extensive empirical study suggests that the approximation error can be as much as about 3%--5% although most samples over the data period exhibit less than 1% errors. Even with the non-negligible errors, the MFIVol may be still considered a valid volatility measure from the perspective of risk-neutral return density, in the sense that it is bounded by the two variability measures as well as reflecting the shape …

Does It Mean? Gene Wolfe: Perverse Puzzle Maker, Marc Anthony Aramini

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study is to re-examine the possibility of determining authorial intention, focusing on an author considered by many to be sui generis, science fiction grandmaster Gene Wolfe, well known for his confusing and difficult texts. Wolfe has a reputation as a “puzzle box” writer. Chapter One will trace some of the critical controversy surrounding his reception. Chapter Two will touch on a shift in recent twentieth- and twenty-first-century criticism from poststructural and deconstructive tenets to a more authentic trust between author and reader, attempting to minimize the implications of the hermeneutic of suspicion without decreasing the richness …

A Novel Feature Maps Covariance Minimization Approach For Advancing Convolutional Neural Network Performance, Bikram Basnet

UNLV Theses, Dissertations, Professional Papers, and Capstones

We present a method for boosting the performance of the Convolutional Neural Network (CNN) by reducing the covariance between the feature maps of the convolutional layers.

In a CNN, the units of a hidden layer are segmented into the feature/activation maps. The units within a feature map share the weight matrix (filter), or in simple terms look for the same feature. A feature map is the output of one filter applied to the previous layer. CNN search for features such as straight lines, and as these features are spotted, they get reported to the feature map. During the learning process, …

Petrogenesis Of Unusual Occurrence Of Amphibole Asbestos In Mohave County, Arizona And Clark County, Nevada, Tomoyo Austin

UNLV Theses, Dissertations, Professional Papers, and Capstones

The term “asbestos” applies to six types of fibrous amphiboles or chrysotile with specific morphologies that are commercially mined and processed. Inhaling asbestos fibers is known to cause many negative health effects, including mesothelioma, several different cancers, various respiratory diseases and non-respiratory diseases, and fatalities. The recent years, several cases of non-occupational exposure to asbestos fibers raised an awareness of environmental exposure to naturally occurring asbestos (NOA) which refers to asbestiform minerals that fall out of the regulatory definition of asbestos.

There are two sources of NOA in the area, Wilson Ridge pluton, AZ, and Boulder City pluton, NV which …

Permutation Flow Shop Via Simulated Annealing And Neh, Pooja Bhatt

UNLV Theses, Dissertations, Professional Papers, and Capstones

Permutation Flow Shop Scheduling refers to the process of allocating operations of jobs to machines such that an operation starts to process on machine j only after the processing completes in j-1machine. At a time a machine can process only one operation and similarly a job can have only one operation processed at a time. Finding a schedule that minimizes the overall completion times for Permutation Flow Shop problems is NP-Hard if the number of machines is greater than 2. Sowe concentrates on approaches with approximate solutions that are good enough for the problems. Heuristics is one way to find …

Storing Iot Data Securely In A Private Ethereum Blockchain, Vinay Kumar Calastry Ramesh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Internet of Things (IoT) is a set of technologies that enable network-connected devices to perform an action or share data among several connected devices or to a shared database. The actions can be anything from switching on an Air Conditioning device remotely to turning on the ignition of a car through a command issued from a remote location or asking Alexa or Google Assistant to search for weather conditions in an area. IoT has proved to be game-changing for many industries such as Supply Chain, Shipping and Transportation providing updates on the status of shipments in real time. This has …

Machine Learning Prediction Of Primary Tissue Origin Of Cancer From Gene Expression Read Counts, Lohitha Chintham Reddy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cancer is a group of diseases characterized by the uncontrolled growth and spread of abnormal cells. Generally, manufacturing of proteins by cells is controlled by genes. Each gene must have the correct instructions for making its protein, so that it allows the protein to perform the correct function for the cell. When one or more genes in a cell mutate and create an abnormal protein, that is when cancer begins. An abnormal protein provides different information compared to a normal protein. This can cause cells to multiply uncontrollably and cause cancer.

RNA sequencing (RNA-seq) can be used to figure out …

Early Contractional History Of The Funeral Mountains And Its Influence On The Formation Of The Funeral Mountains Metamorphic Core Complex, Death Valley, Ca, Taylor Douglas Craig

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zones of localized crustal thickening in orogenic belts commonly host low-angle normal faults, which have been controversial since their recognition. The metamorphic core complexes of the Sevier hinterland are localized within a belt that is attributed with the highest degrees of crustal thickening during Sevier orogenesis. This association of deep-rooted detachment faulting and early contractional deformation indicates an important link between the two processes, however repeated tectonic episodes often overprint and obscure the earlier fabrics, making this link difficult to study. The Funeral Mountains metamorphic core complex, located in Death Valley, CA, has a complex history of protracted SE-contraction and …

Super Rapid Crystal Growth And Quench Of Monoclinic Bi-Ii* During Dynamic Compression, Zachary Allen Fussell

UNLV Theses, Dissertations, Professional Papers, and Capstones

We show that monoclinic Bi-II* forms during a dynamic compression regime with crystal growth rates from melt of ≈ 70 m/s. This extreme quench rate implies crystallization by non-diffusive processes and indicates that the liquid had a high degree of pre-ordering. Using ambient condition single crystal structure analysis we show for the first time that the monoclinic distorted phase of Bi (Bi-II) exists at ambient pressure, albeit bound to formation under dynamic compression. We review the pressure, temperature, and time conditions for formation and growth of this structure.

Machine Learning Classification Of Primary Tissue Origin Of Cancer From Dna Methylation Markers, Sravani Gannavarapu Surya Naga

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cancer is one of the leading causes of death globally and was responsible for approximately 9.6 million deaths in 2018. One of the main reason for deaths from cancer is late-stage presentation and inaccessible diagnosis and treatment. Cancer often spreads from the part of the body where it started (primary site) to a different part of the body (metastatic site). Identifying the primary site of cancer plays a key role as it directs the appropriate treatment. Cancer which spreads needs the same treatment as its origin. Having this knowledge can help doctors to decide the type of treatment.

All cancers …

Telomeres, Nutrition And Mortality: Risk Factors For The Rate Of Telomere Length Decline And The Associations Between Telomere Length, Nutrition And Mortality, Saruna Ghimire

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Telomeres are nucleoprotein structures located at the ends of eukaryotic chromosomes, thought to protect the DNA from damage. As a person experiences stressors, harmful exposures, and other diseases throughout their life, telomeres are thought to become damaged and their length shortened, decreasing their ability to protect the DNA. Nutrition is an important aspect of healthy aging. Preservation of telomere length (TL) is thought to be one of the mechanisms by which good nutrition can delay or prevent the development of chronic disease and death. Recent evidence of preservation of TL with good nutrition is promising. Thus, the aim of …

Equation Of State Of H2o Ice Using Melt-Recrystallization, Zachary Michael Grande

UNLV Theses, Dissertations, Professional Papers, and Capstones

The recent surge in exoplanet discoveries due to advancements in astrophysical technology and analysis has brought the reliability of early equation of state measurements into question as they are the limiting factor when modeling composition of these planets. H2O content is among the most important for the search of habitable planets as well as in understanding planetary dynamics and atmosphere formation. Over the last three decades the equation of state of H2O has been investigated with various techniques but, has suffered from anisotropic strain and poor powder statistics resulting in a large discrepancy in equation of state fits. At pressures …

Implications Of An Iterative Design Experiment In Transcendental And Polynomial Functions Within A Flipped Classroom, Aaron Boyd Harris

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study explores an iterative design research experiment of a flipped mathematics classroom over the span of five curricular units involving big ideas of transcendental and polynomial functions. Transcendental and polynomial functions involve an algebraic, analytic, and graphical approach to the concepts and procedures of exponential, logarithmic, power, cubic, quadratic, linear, and rational functions. The Compleat design research methodology (Middleton, Gorard, Taylor, & Bannan-Ritland, 2008) was used to explore a series of instructional sequences that an instructor implemented in a flipped classroom while teaching big ideas of transcendental and polynomial functions.

The experiment occurred over the course of a sixteen-week …

Numerical Analysis And Fluid Flow Modeling Of Incompressible Navier-Stokes Equations, Tahj Hill

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Navier-Stokes equations (NSE) are an essential set of partial differential equations for governing the motion of fluids. In this paper, we will study the NSE for an incompressible flow, one which density ρ = ρ0 is constant.

First, we will present the derivation of the NSE and discuss solutions and boundary conditions for the equations. We will then discuss the Reynolds number, a dimensionless number that is important in the observations of fluid flow patterns. We will study the NSE at various Reynolds numbers, and use the Reynolds number to write the NSE in a nondimensional form.

We will …

High-Pressure High-Temperature Exploration Of Phase Boundaries Using Raman Spectroscopy, Jasmine Kashmir Hinton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Metastability of states can provide interesting properties that may not be readily accessible in a material’s ground state. Many materials show high levels of polymorphism, indicating a rich energy landscape and a potential for metastable states. Melt crystallization techniques provide a potential route to these states. We use a resistively heated diamond anvil cell (DAC) with fine control of a system’s pressure and temperature to explore these systems. Raman spectroscopy is used to track subtle structural changes across phase boundaries. Organic systems, such as glycine and aspirin, were our initial interest due to their high polymorphism and reported low melting …

Effects Of Ecological Restoration Techniques In Glen Canyon National Recreation Area, Simone Ka-Voka Jackson

UNLV Theses, Dissertations, Professional Papers, and Capstones

A better understanding of key ecological restoration techniques can inform land management in the Southwest on restoration options for areas infested by invasive grasses that can pose threats to ecosystems, from changes in nutrient cycling to altered fire regimes. In the semi-arid desert of Glen Canyon National Recreation Area (GLCA), several exotic grasses pose risks to local ecosystems: Saccharum ravennae, a relatively new invasive perennial grass, and Bromus rubens and Bromus tectorum, widespread annual grasses. In this study, multiple ecological restoration techniques were implemented to assess their effects on native and nonnative vegetation on sites invaded by the non-native grasses …

K-Tuple Sampling From Partially Rank-Ordered Sets, Marvin Javier

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the introduction of Ranked Set Sampling (RSS), McIntyre (1952) demonstrated that using ranking information to select units for measurement can lead to estimators with reduced variance when compared to their counterparts based on a simple random sample of the same size. This is done by selecting a set of units, and without direct measurement, ranking the units in the set before identifying one unit for measurement. This ranking of the units can be done through judgement ranking (such as visual assessment), or by using a correlated auxiliary variable.

In its original form, RSS does not allow for ties when …

Batching Problems With Constraints, Shradha Kapoor

UNLV Theses, Dissertations, Professional Papers, and Capstones

There is an increasing demand for a phenomenon that can manifest benefits gained from grouping similar jobs together and then scheduling these groups efficiently. Batching is the decision of whether or not to put the jobs into same group based on certain criteria. Batching plays a major role in job scheduling in Information Technology, traffic controlling systems, and goods-flow management. A list batching problem refers to batching a list of jobs in the same order or priority as given in the problem.

In this thesis we consider a one-machine list batching problem under weighted average completion. Given sequence of jobs …