Physical Sciences and Mathematics Commons^™

Petrology And Geochemistry Of The Enriched Poikilitic Shergottite Northwest Africa 10169: Insight Into The Martian Interior, Logan Matthew Combs

UNLV Theses, Dissertations, Professional Papers, and Capstones

The martian meteorite Northwest Africa (NWA) 10169 is classified as a new member of the geochemically enriched poikilitic shergottites, based on mineral composition, Lu-Hf isotope systematics, and rare earth element (REE) composition. Akin to other poikilitic shergottites, it shows a similar bimodal texture to other enriched and intermediate poikilitic shergottites. In addition, olivine and pyroxene in the poikilitic zone have higher Mg#’s (Mg/Mg+Fe) than those in the interstitial areas, suggesting that the poikilitic texture represents early-stage crystallization, opposed to late-stage non-poikilitic crystallization. Calculated fO2 values are reduced (FMQ -2.3 ± 0.23) within the poikilitic texture, and more oxidized (FMQ -1.07 …

A Comparison Of The Product Topology On Two Trees With The Tree Topology On The Concatenation Of Two Trees, Katlyn Kathleen Cox

UNLV Theses, Dissertations, Professional Papers, and Capstones

A game tree is a nonempty set of sequences, closed under subsequences (i.e., if p ∈ T

and p extends q, then q ∈ T). If T is a game tree, then there is a natural topology on [T],

the set of paths through T. In this study we consider two types of topological spaces, both

constructed from game trees. The first is constructed by taking the Cartesian product of

two game trees, T and S: [T] × [S]. The second is constructed by the concatenation of two

game trees, T and S: [T ∗ S]. The goal of our …

Deep Data Locality On Apache Hadoop, Sungchul Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

The amount of data being collected in various areas such as social media, network, scientific instrument, mobile devices, and sensors is growing continuously, and the technology to process them is also advancing rapidly. One of the fundamental technologies to process big data is Apache Hadoop that has been adopted by many commercial products, such as InfoSphere by IBM, or Spark by Cloudera. MapReduce on Hadoop has been widely used in many data science applications. As a dominant big data processing platform, the performance of MapReduce on Hadoop system has a significant impact on the big data processing capability across multiple …

Design Guidelines And Strategies For Thermal Solar Management Of Fenestration In The Desert Climate, David Mccredo

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research evaluates the effects of varying thermal properties of windows in

residential energy use for the moderate altitude and 36'N latitude climate of southern

Nevada, which has a distinct cooling season. A selection of windows across different

shading conditions and total window areas were studied using BEopt energy simulation.

Findings demonstrate that for the specific climate, latitude, and altitude of Las Vegas,

Nevada, the most expensive “high performance” windows are not always the best

option in terms of total site energy use, and can be outperformed by properly shaded

less advanced windows. Under certain conditions, shading was found to …

Primordial Black Holes In The Cosmological Context And Transient Electromagnetic Signatures From Merging Black Hole Binaries, Jared Robert Rice

UNLV Theses, Dissertations, Professional Papers, and Capstones

The cosmological evolution of primordial black holes (PBHs) is presented via analysis of the accretion and evaporation histories of the holes. The ultimate end of any BH is evaporation — a spectacular seconds-long burst of high-energy radiation and particles. The critical initial mass of a PBH undergoing current era evaporation is ∼ 510 trillion grams. A near- critical mass PBH will not accrete radiation or matter in sufficient quantity to retard its inevitable evaporation, if the hole remains within an average volume of the universe. The gravitational waves (GWs) from five BH binary merger events discovered by the LIGO/Virgo collaborations …

Use Of Sodium Bismuthate Chromatography For Separation Of Americium From Curium And Other Elements In Spent Nuclear Fuel, Jason Michael Richards

UNLV Theses, Dissertations, Professional Papers, and Capstones

A novel method for partitioning americium from curium has been developed using sodium bismuthate as both an oxidant and a separation medium. The presence of americium and curium in nuclear waste increases the heat load in geological repositories and leads to larger waste volumes. These elements are also the source of most of the long-term radiotoxicity of the waste. However, the heat load and long-term radiotoxicity contribution from americium is much greater than that from curium. The contribution of curium to the heat load and radiotoxicity of the waste is significant on the same time scale as longer-lived fission products …

Solvent Extraction And Extraction Chromatography Of Homologs And Pseudohomologs Of Rutherfordium Using Teha And Tehp, Jeffrey Rolfes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studies of the chemical properties of the heaviest elements have always been difficult due to the short half-lives and low cross sections involved. To solve this problem, atom-at-a-time methods are necessary to determine the properties of these short-lived isotopes. Extremely fast kinetics for the chemical reactions studied (on the same order as the nuclide’s half-life) are required, and the system should have the potential for automation. Solvent extraction, with its selectivity and quick kinetics, has historically been used for these investigations into characteristics of super heavy elements. Another technique, extraction chromatography, offers potentially a way of investigating rutherfordium’s properties, without …

Applications Of Nanoporous Materials In Gas Separation And Storage, Amit Sharma

UNLV Theses, Dissertations, Professional Papers, and Capstones

Past decades in the field of gas separation and storage utilized the concepts of both cryogenic distillation and non-cryogenic methods such as high-pressure cylinders but few concerns – efficiency, energy intensiveness, cost associated, risk of failure always existed. Recent advances in the field focuses on using porous materials especially nanoporous materials. Nanoporous materials, due to their well-defined structure, range of pore diameters, and striking surface chemistry hold over traditional porous materials for gas separation and storage. With pore diameter less than 2 nm and abundance of energetically favorable sites (such as unsaturated metal sites, channels, cages, cavities etc.), these materials …

Fundamental Tradeoffs In Estimation Of Finite-State Hidden Markov Models, Justin Le

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hidden Markov models (HMMs) constitute a broad and flexible class of statistical models that are widely used in studying processes that evolve over time and are only observable through the collection of noisy data. Two problems are essential to the use of HMMs: state estimation and parameter estimation. In state estimation, an algorithm estimates the sequence of states of the process that most likely generated a certain sequence of observations in the data. In parameter estimation, an algorithm computes the probability distributions that govern the time-evolution of states and the sampling of data. Although algorithms for the two problems are …

Larval-Ant Interactions In The Mojave Desert: Communication Brings Us Together, Alicia Mellor

UNLV Theses, Dissertations, Professional Papers, and Capstones

Butterflies are a diverse and essential group of pollinators whose abundance is predominantly determined by growth and survival of their larvae. In the family Lycaenidae, many species participate in a larval-ant mutualism where ants feed on nutrient-rich nectar produced by larvae and, in turn, protect those larvae from predators. Emerging evidence indicates larval scent in the form of cuticular hydrocarbons (CHCs), not nectar production, drives this interaction. This study takes two approaches to investigate CHCs as the driver behind the larval-ant mutualism in three butterfly species native to southern Nevada: Euphilotes bernardino martini (Martin’s blue), Brephidium exilis (western pygmy blue), …

Development Of Chemical Separation Methods Using Transition Metals For Nuclear Forensic And Medicinal Applications, Lucas Peter Boron-Brenner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Insufficient data exists on the effects of prompt fast neutron activation on metals found commonly in nuclear devices and the urban environment. Different metals such as Ti, Au, Fe, and Cu were activated using the Flattop Criticality Benchmark at the Device Assembly Facility on the Nevada Test Site using a known neutron spectrum and flux to determine a baseline cross section value. Cross section information gathered from these neutron activation measurements could provide information that helps government and law enforcement agencies to correctly trace the origin of a nuclear device’s fuel or component features.

Based on activation products produced in …

Advancing Community Detection Using Keyword Attribute Search, Sanket Chobe

UNLV Theses, Dissertations, Professional Papers, and Capstones

As social network structures evolve constantly, it is necessary to design an efficient mechanism to track the influential nodes and accurate communities in the networks. The attributed graph represents the information about properties of the nodes and relationships between different nodes, hence, this attribute information can be used for more accurate community detection. Current techniques of community detection do not consider the attribute or keyword information associated with the nodes in a graph. In this thesis, I propose a novel ideal of online community detection using a technique of keyword search over the attributed graph. First, the influential attributes are …

Algorithms For Tower Placement On Terrain, Binay Dahal

UNLV Theses, Dissertations, Professional Papers, and Capstones

We review existing algorithms for the placement of towers for illuminating 1.5D and 2.5D terrains. Finding the minimum number of towers of zero height to illuminate 1.5D terrain is known to be NP-Hard. We present approximation algorithms for solving two variations of the tower placement problem. In the first variation, we consider the placement of a single tower of given height to maximize visibility coverage. In the second variation, we consider the problem of placing reduced number of common height towers to cover the entire terrain. Algorithms for solving both problem variations are based on discretizing the problem domain by …

Concurrency In Blockchain Based Smartpool With Transactional Memory, Laxmi Kadariya

UNLV Theses, Dissertations, Professional Papers, and Capstones

Blockchain is the buzzword in today's modern technological world. It is an undeniably ingenious invention of the 21st century. Blockchain was first coined and used by a cryptocurrency namedBitcoin. Since then bitcoin and blockchain are so popular that every single person is taking on bitcoin these days and the price of bitcoin has leaped to a staggering price in the last year and so.Today several other cryptocurrencies have adapted the blockchain technology.

Blockchain in cryptocurrencies is formed by chaining of blocks. These blocks are created by the nodes called miners through the process called Proof of Work(PoW). Mining Pools are …

Breaking The Language Barrier: Equitable Assessment In General Chemistry, Eshani Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Because language provides the framework through which knowledge is constructed, it is crucial to consider the ways in which students with limited English proficiencies are able to express their understanding. English language learners (ELLs) make up a significant portion of the student body in the education system and represent many ethnic and racial minorities in STEM (Science, Technology, Engineering & Mathematics) fields (Burke & Mattis, 2007). Despite the national push to build a more diversified, STEM-ready workforce, there is little research that considers the way ELLs are assessed in STEM courses at the postsecondary level. Literature reports that science tests …

Structural Evolution And Regional Implications Of The Arrowhead Mine Fault Within The Pahranagat Shear Zone, Nevada, Usa, Michael Dennis Evans

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Basin and Range province is characterized by normal faults associated with

extension, but the occurrence of strike-slip faults and the seismic hazard accompanying

them is less understood. One major strike-slip zone, the Pahranagat shear zone (PSZ),

lies in Lincoln County, Nevada and within the boundary zone between northern Basin

and Range (NBR) and central Basin and Range (CBR) sub-provinces. The PSZ is a 20-

25 km long zone of Cenozoic left-lateral faults. The Arrowhead Mine Fault (AMF) is one

of the three major faults in the PSZ. The western AMF and the faults that surround and

abut it are …

Evaluation Of A Continuous Air Monitoring System On An Unmanned Aerial Vehicle For Measurement Of Airborne Radioactive Material, Adam Pfannenstein

UNLV Theses, Dissertations, Professional Papers, and Capstones

The release of airborne radioactive material presents a health risk hazard to many individuals, emergency responders and public. It is necessary to characterize the unknown radioactive dangers produced in the event of these incidents. Advantages to utilizing unmanned aerial systems in this effort are personnel risk reduction and quick attainment of data points in a plume. By pairing a continuous air monitor and detector with a drone, radioactive material concentration can be quantified, and thus the extent of potential doses can be estimated. A small, low-flow air sampler with a Geiger-Mueller counter was characterized using measurements of sources representing a …

Notes On Linear Divisible Sequences And Their Construction: A Computational Approach, Sean Trendell

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this Masters thesis, we examine linear divisible sequences. A linear divisible sequence is any sequence {an}n≥0 that can be expressed by a linear homogeneous recursion relation that is also a divisible sequence. A sequence {an}n≥0 is called a divisible sequence if it has the property that if n|m, then an|am. A sequence of numbers {an}n≥0 is called a linear homogeneous recurrence sequence of order m if it can be written in the form

an+m = p1an+m−1 + p2an+m−2 + · · · + pm−1an+1 + pman, n ≥ 0,

for some constants p1, p2, ..., pm with pm = …

Design On High Performance Nanoscale Cmos Circuits With Low Temperature Sensitivity, Ming Zhu

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the rapid development of integrated circuit (IC) design and manufacturing technology, the transistor size now can be shrunk into only couple of nanometers whereas billions of transistors can be squeezed into a square millimeter, providing unprecedented computation power. However, accompanied with continuous device miniaturization and increased integration density is the explosive growth of on-chip power dissipation and a wide range of temperature fluctuation, which can heavily and negatively affect the delay performance of the circuit, or in the worst case, the circuit may malfunction and the system can be unreliable. Therefore, improved performance resilience against temperature variations has become …

Hexavalent Chromium Removal From Residual Ion-Exchange Brine Using Ferrous Sulfate, Ana Luiza De Araujo Silva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Removal of hexavalent chromium (Cr(VI)) from water and wastewater is required for health purposes and regulation compliance. Among the technologies available, ion exchange (IX) has been extensively applied and, in most cases, is followed by resin regeneration for the purpose of cost optimization. However, resin regeneration produces residual IX brine, also called waste regenerant brine, which is considered hazardous for containing the contaminant(s) treated in the column. This research focuses on the use of ferrous sulfate (FeSO4) to reduce and precipitate Cr(VI) contained in the regenerant brine from IX resins. The Cr(VI) reduction to trivalent chromium (Cr(III)) occurs due to …

Static And Dynamic Quantitative Microbial Risk Assessment Of Potable Reuse Paradigms, Erfaneh Amoueyan

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years, potable reuse applications have become more common due to population growth and increased water demand, especially in communities with limited or variable water resources. However, there are concerns about potential exposure to pathogens and chemical compounds in treated wastewater. Therefore, advanced wastewater treatment processes are of paramount importance in any potable reuse system. The overall aim of this study was to develop and implement static and dynamic QMRAs to compare public health risk in various potable reuse scenarios. Cryptosporidium, norovirus, adenovirus, and Salmonella were chosen as the target pathogens. The research evaluated the performance of full advanced …

Bi-Directional Testing For Change Point Detection In Poisson Processes, Moinak Bhaduri

UNLV Theses, Dissertations, Professional Papers, and Capstones

Point processes often serve as a natural language to chronicle an event's temporal evolution, and significant changes in the flow, synonymous with non-stationarity, are usually triggered by assignable and frequently preventable causes, often heralding devastating ramifications. Examples include amplified restlessness of a volcano, increased frequencies of airplane crashes, hurricanes, mining mishaps, among others. Guessing these time points of changes, therefore, merits utmost care. Switching the way time traditionally propagates, we posit a new genre of bidirectional tests which, despite a frugal construct, prove to be exceedingly efficient in culling out non-stationarity under a wide spectrum of environments. A journey surveying …

Holocene Climate Evolution Of Continental Western Eurasia Constrained By Stable-Isotope And Cation Geochemistry Of U-Th-Dated Speleothems And Meteogenic Travertine, Jonathan Lloyd Baker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Reliable reconstructions of global and regional climate during the Holocene (11,700 years ago to present) are vital to constraining the natural range of climate variability and testing state-of-the-art models, which seek to forecast the near- and long-term impact of anthropogenic greenhouse forcing. Much of continental Eurasia is still underrepresented, however, in geological proxy reconstructions of Holocene climate variability, and the vast majority of paleoclimate data only reflect conditions during peak summer months (JJA) or the growing season. The paucity of winter proxy data has therefore been cited as a possible explanation for the current mismatch between geological proxy-based and climate-model …

Separation Of Neighboring Trivalent Lanthanides For Neutron Capture Cross Section Measurements, Balazs Jozsef Bene

UNLV Theses, Dissertations, Professional Papers, and Capstones

The determination of the low-energy neutron capture cross-section of 171Tm with greater accuracy is important for both astrophysics and Stockpile Stewardship. Thulium-171 is a branching point in the s-process of stellar nucleosynthesis. Branching point nuclei, with half-lives in the order of 1 – 100 years are places where neutron capture and beta decay competes. This isotope is also the second order (n, γ) reaction product of 169Tm, which was used as a radiochemical detector in nuclear weapon experiments. It was placed at strategic locations in nuclear devices. Following the test, samples were analyzed in the collected samples for products of …

Meshless Methods For Numerically Solving Boundary Value Problems Of Elliptic Type Partial Differential Equations, Minhwa Choi

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation we propose and examine numerical methods for solving the boundary value problems of partial differential equations (PDEs) by meshless methods. First we aim at getting approximate particular solutions up of a nonhomogeneous equation by radial basis methods. For instance, the collocation method by radial basis functions (RBFs) for finding particular solutions is very popular in the literature. Now the particular solutions of certain important PDEs by RBF approximation are available with the order of convergence to the exact solutions provided. Here we explore and examine the numerical performances of these particular solutions in various examples. We then …

Elliptic Cryptosystem, Elizabeth Dettrey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The elliptic cryptographic algorithm first presented in a paper by E. F. Dettrey and E. A. Yfantis is examined and explained in this thesis. The algorithm is based on the group operations of a set of points generated from an ellipse of arbitrary radii, and arbitrary center in the case of the generalized version, modulo a large prime. The security of the algorithm depends on the difficulty of solving a discrete logarithm in the groups used by this algorithm. While the elliptic cryptographic algorithm is not the most secure among the discrete logarithm based paradigm of cryptosystems for a given …

Determination Of Anthropogenic Radionuclides In Ocean Water Using Extraction Chromatography, Jaimie Daum

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the aftermath of the reactor accident in Fukushima, it has become obvious that there is a severe lack in methods that would allow for the rapid determination of anthropogenic radionuclides in ocean water. Current radioanalytical techniques for the determination of radionuclides in natural waters have a number of disadvantages including the fact that they are time consuming, generate a substantial amount of waste, and are typically multi-step processes. Additionally, the elevated amount of dissolved ions in ocean water imparts a complex matrix that can interfere with the rapid separation and determination of anthropogenic radionuclides. Therefore, due to the size, …

Miocene-Quaternary Deformation Along The Central Maynard Lake Fault, Pahranagat Shear Zone, Nevada, Alexander Peck

UNLV Theses, Dissertations, Professional Papers, and Capstones

The left-lateral Pahranagat shear zone (PSZ) and Caliente-Enterprise zone (CEZ) exist at the boundary between two sub-provinces, the Northern (NBR) and Central Basin and Range (CBR). The PSZ contains three major ENE striking sinistral faults, including the Maynard Lake fault (MLF), which is the longest fault and marks the southern boundary of the zone. The PSZ has been suggested to be a transfer zone, but little is known about the structures along these major faults that are involved in strain transfer. These left-lateral systems exist within the Central Nevada seismic belt which has experienced significant earthquakes in recent history. Possible …

Machine Learning Applications In Graduation Prediction At The University Of Nevada, Las Vegas, Elliott Collin Ploutz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Graduation rates of four-year institutions are an increasingly important metric to incoming students and for ranking universities. To increase completion rates, universities must analyze available student data to understand trends and factors leading to graduation. Using predictive modeling, incoming students can be assessed as to their likelihood of completing a degree. If students are predicted to be most likely to drop out, interventions can be enacted to increase retention and completion rates.

At the University of Nevada, Las Vegas (UNLV), four-year graduation rates are 15% and six-year graduation rates are 39%. To improve these rates, we have gathered seven years …

A Machine Learning Approach To Predict First-Year Student Retention Rates At University Of Nevada, Las Vegas, Aditya Rajuladevi

UNLV Theses, Dissertations, Professional Papers, and Capstones

First-year student retention rates for a four-year institution refers to the percentage of First-time Full-time students from the previous fall who return to the same institution for the following fall. First-year retention rates act as an important indicator of the student satisfaction as well as the performance of the university. Moreover, universities with low retention rates may face a decline in the admissions of talented students with a notable loss of tuition fees and contributions from alumni. Therefore, it is important for universities to formulate strategies to identify students who are at risk of not being retained and take necessary …