Digital Commons Network^™

Four Local Colorings Of Graphs, James Katseanes

UNLV Retrospective Theses & Dissertations

A power coloring of a graph G is a mapping c : V (G) → N that assigns colors to the vertices of G in such a way that adjacent vertices are labeled with different colors. A coloring c is called a 4-local coloring if for every subset S ⊆ V (G), with 2 ≤ |S| ≤ 4 there are two vertices u, v such that the difference between colors of u and v, is greater than or equal to the number of edges in the subgraph induced by S. That is, ∀S∃u,v∈ S∋&vbm0;cu-c v&vbm0;≥ms, where ms is the number …

Applying Of Mechanical Failure Criteria Of Brittle Material To The Design Of High Temperature Heat Exchanger, Taha Mohamed

UNLV Retrospective Theses & Dissertations

Previous studies have suggested using a ceramic high temperature heat exchanger as a sulfuric acid decomposer for hydrogen production within the sulfur iodine thermochemical cycle. The decomposer was manufactured using fused ceramic layers that allow the creation of channels with dimensions below one millimeter. The heat exchanger is expected to operate in the range of 950°C. Thermal stresses are however induced in the heat exchanger ceramic components. In this study, proper failure criteria are selected to evaluate the safety level of the ceramic components. A three-dimensional computational model is developed to investigate the fluid flow, heat transfer, stresses and chemical …

A Study Of Sprt Algorithm And New-Guard For Radiation Detection, Venkatachalam Palaniappan

UNLV Retrospective Theses & Dissertations

A novel and efficient radiation detection algorithm combined with a measuring unit will produce an ideal detector to battle field radiation measurement problems. Studies of Sequential Probability Ratio Test (SPRT) for radiation detection are essential towards developing efficient and accurate radiation detection algorithms. In this study, the performance of the classical Single-Threshold-Test (STT) and the SPRT First-In-First-Out (FIFO) algorithms is considered. Next, improvements made by the Last-In-First-Elected-Last-Out (LIFELO) algorithm are analyzed. Further, enhancements to the LIFELO algorithm, using the Dynamic Background Updating and Maximum Likelihood Estimator (MLE), are performed; The thesis also provides detailed requirements for an innovative hand-held radiation …

Determining Thermal Conductivity And Absorption Coefficient Of Semi-Transparent Liquids Using Numerical And Experimental Approach, Jayant Prabhakar Patil

UNLV Retrospective Theses & Dissertations

Thermal properties of the molten salts are emerging as one of the important areas of research. The motivation for this particular research originated from the use of molten salts in high temperature heat exchangers. The molten salts are transparent liquids at their melting point. Considering this aspect of molten salt which resembles with water the research is conducted on water and glycerin. The effect of radiation along with conduction is studied in calculating the thermal conductivity of water; The effect of radiation on thermal conductivity is calculated using Rosseland's approximation method. Thermal conductivity is calculated as function of temperature. Different …

Quantitative Comparison Of Sample Preparation Methods For Low-Level Alpha Spectrometry, Sherry Alina Stock

UNLV Retrospective Theses & Dissertations

There are currently several widely accepted methods of sample preparation procedures for alpha spectroscopy. Alpha spectroscopy is becoming more important due to increased concentration on nuclear waste management, site decontamination and decommissioning, and environmental assessment. Due to increased emphasis on emergency response and preparedness, there is a strong desire to make the analysis of samples as quick and efficient as possible. Three methods evaluated in this project are electrodeposition, microprecipitation, and evaporation. Actinides are the main elements of concern, namely a tracer of241Am is used. Each method is itself optimized and evaluated quantitatively, and then the methods are compared against …

Thermal Control For The Liquid Metal Coolant Circulation Loop, Xiuju Tan

UNLV Retrospective Theses & Dissertations

The target complex facility (TC-1 facility) located at University of Nevada, Las Vegas (UNLV), is serving the fundamental research of thermal-hydraulics and corrosion test of liquid metal coolant lead bismuth eutectic (LBE). A stable thermal condition is the basis for the TC-1 facility to operate and target coolant LBE to circulate throughout the loop made of the main components of TC-1 facility, TC-1 loop. The proper thermal process of the TC-1 loop critically comprises a smooth heating phase, the main intention of which is to warm all the loop components and melt solid LBE; a stable temperature maintenance phase, which …

Document Type Classification From Document Images, Jason Montgomery Vergara

UNLV Retrospective Theses & Dissertations

The most common features that classification systems use is simply to consider all words as features and determine the probability of the document's category based on these words. When given document images, sophisticated optical character recognizers can be used to provide more than the simple text that traditional classification systems use. This metadata and extracting additional features from the document text can improve classification of document images; We have found a greater than 1% increase in recall when looking at font size metadata and extracting other features such as words used in uppercased lines. Since our dataset can have multi-page …

Suicide By Firearm, Suicide Fatality, And Firearm Availability, Andrea Wallick

UNLV Retrospective Theses & Dissertations

This study has three objectives. The first two objectives are to determine if neighborhood level gun availability has an effect on suicide method and suicide fatality. The third is to test that para-suicides (i.e., attempted suicides) with a mental disorder are more likely than para-suicides without a mental disorder to attempt suicide by firearm. Neighborhood is defined by zip code. The number of homicides for each zip code divided by the number of firearm related homicides in each zip code is used as a proxy for neighborhood level gun availability. Data on suicides and para-suicides occurring in Chicago front 1990-1997 …

Evaluation Of Fluorapatite As A Waste-Form Material, Dennis W. Lindle, Oliver Hemmers, Dale L. Perry

Separations Campaign (TRP)

Argonne National Laboratory has proposed a new extraction procedure to handle TRISO-coated fuels, the Fluoride Extraction Process, or FLEX. The FLEX process is designed to separate the uranium in the fuel from the actinides and most fission products by taking advantage of the unique properties of uranium hexafluoride (UF₆). In the FLEX process, the used TRISO fuel is reacted with zirconium fluoride salt, forming UF₆ and the fluoride salts of the actinides and fission products. At process temperatures, the UF₆ volatizes into a gas, and is released from the molten salt mixture. This leaves behind the …

Using Cluster Analysis To Evaluate The Academic Performance Of Demographic Homogeneous Subsets, Jeffrey N Halsell

UNLV Retrospective Theses & Dissertations

No Child Left Behind (NCLB) requires states to develop, under very specific conditions, a valid and reliable system of measurement that meets certain requirements while neglecting others. One such provision is a system of assessments that holds all schools to the same academic criteria, regardless of circumstance, while at the same time acknowledging an achievement gap exists between certain subpopulations of students. Nevada has developed such a program, which effectively fulfills the requirements of NCLB, and like NCLB, neglects to recognize the unique challenges for those schools housing larger than average populations of lower-performing students; Historically, when discussing the achievement …

Design Implementation And Analysis Of A Dynamic Cryptography Algorithm With Applications, Sourabh Ghose

UNLV Retrospective Theses & Dissertations

Cryptographers need to provide the world with a new encryption standard. DES, the major encryption algorithm for the past fifteen years, is nearing the end of its useful life. Its 56-bit key size is vulnerable to a brute-force attack on powerful microprocessors and recent advances in linear cryptanalysis and differential cryptanalysis indicate that DES is vulnerable to other attacks as well. A more recent attack called XSL, proposes a new attack against AES and Serpent. The attack depends much more critically on the complexity of the nonlinear components than on the number of rounds. Ciphers with small S-boxes and simple …

Monte Carlo Analysis Of The Luminosity Function Of Gamma Ray Bursts, Francisco Javier Virgili

UNLV Retrospective Theses & Dissertations

Gamma-ray bursts are cosmological explosions that result in a massive release of radiation ranging from high-energy-gamma rays and x-rays as well as possible long lasting optical and radio tails. Bursts are a result of processes occurring in old stars and their by-products, namely black holes and neutron stars. Gamma-ray bursts tied to the deaths of stars are known as long gamma-ray bursts and are the subject of this study. Data from various missions including NASAs Compton Gamma Ray Observatory and Swift Gamma-ray Mission (Swift) shows that typical GRBs lie within a luminosity range of roughly 1049 to 1054 ergs s-1 …

Mathematical Modeling Of Magnetohydrodynamic Micropumps, Juan Katoff Afonien

UNLV Retrospective Theses & Dissertations

A lab-on-a-chip (LOC) system is a minute chemical processing plant consisting of interconnected networks of microchannels and reservoirs operating with small volumes of reagents. In many LOC systems, it is necessary to propel fluids from one part of the device to another, control fluid motion, stir and interact various reagents, and detect the presence of target analytes. In LOC systems, these tasks are far from trivial; This thesis focuses on fluid propulsion under the action of electric and magnetic fields. Both Non-RedOx and RedOx-based Magneto-hydrodynamic (MHD) micropumps, in which the flow is directed by judicious interplay between electric and magnetic …

Chemical Analyses In Support Of Yucca Mountain Studies, Harry Reid Center For Environmental Studies, University Of Nevada, Las Vegas

Publications (YM)

Research Objectives: Provide preparation of injectates, sorption studies and analyses for tracer tests Provide REE, trace metals, majors and field measurement data from wells of the Nye County Early Warning Drilling Program (NCEWDP)and Inyo County Other laboratory needs as they arise

Design And Performance Of A Curved-Crystal X-Ray Emission Spectrometer, A. C. Hudson, Wayne C. Stolte, Dennis W. Lindle, Renaud Guillemin

Chemistry and Biochemistry Faculty Research

A curved-crystal x-ray emission spectrometer has been designed and built to measure 2–5 keV x-ray fluorescence resulting from a core-level excitation of gas phase species. The spectrometer can rotate 180°, allowing detection of emitted x rays with variable polarization angles, and is capable of collecting spectra over a wide energy range (20 eV wide with 0.5 eV resolution at the Cl K edge) simultaneously. In addition, the entire experimental chamber can be rotated about the incident-radiation axis by nearly 360° while maintaining vacuum, permitting measurements of angular distributions of emitted x rays.

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix, Kenneth Czerwinski

Fuels Campaign (TRP)

This project will examine inert fuels containing ZrO₂ and MgO as the inert matrix. Ceramics with this inert matrix, Ce, U and eventually Pu will be synthesized and examined. While the Advanced Fuel Cycle Initiative focus is on inert fuels with Pu as the fissile component, this task will perform initial laboratory experiments with Ce and U. The initial work with Ce will be performed early in the project with results used as a basis for U studies. Reactor physics calculations will be used to examine suitable quantities of burnable poisons from the candidate elements Gd, Er, or Hf. …

Understanding Multiple Intelligences: Best Practice: Effective Programs Meet The Needs Of People With Diverse Intelligences, Sky Mcclain, Allison Brody

Education about the Environment

Have you ever wondered why someone who is very smart has trouble using a map? Why one person can follow a map, but is confused by written instructions? Howard Gardner devised an explanation with the theory of multiple intelligences, presented in his 1983 book Frames of Mind.

Gardner questioned the idea that intelligence is a single entity and that it can be measured simply using IQ tests. Rather, he argued that each of us perceives and processes information in multiple ways. And our learning styles reflect these multiple intelligences, with some of us learning more easily by seeing, others by …

Interaction Between Metal Fission Products And Triso Coating Materials, Clemens Heske

Fuels Campaign (TRP)

This project focuses on the chemical bonding and interface formation of metal fission products with the coating materials used in tri-isotropic (TRISO) fuel particles for gas-cooled reactors. By combining surface- and bulk-sensitive spectroscopic methods, intermediate chemical phases at the interface, intermixing/ diffusion behavior, and the electronic interface structure as a function of material (metal and coating materials) and temperature are examined.

In the past year, emphasis was placed on a detailed analysis and description of the Cs/SiC interface formation process.

Reactor Physics Studies For The Afci Reactor-Accelerator Coupling Experiments Project, Denis Beller

Transmutation Sciences Physics (TRP)

The specific research objective of this three-year project is to design and conduct accelerator driven experiments, which will help demonstrate in the U.S. the ability to design, compute, and conduct ADSS experiments and to predict and measure source importance, coupling efficiency, sub-critical reactor kinetics and source-driven transients. In addition, databases will be created for both steady state and transient ADSS experiments for the nuclear community to develop and test new computational codes and methods, and the importance of a driving neutron source in various regions of different subcritical assemblies will be mapped. Experiments will be conducted and compared to calculations …

Criticality Studies For Urex Processes, Denis Beller

Separations Campaign (TRP)

The completion of criticality experiments for mixtures of transuranic actinides (TRU–includes Np, Pu, Am, and Cm) that will be created during the separation of used nuclear fuel may be a requirement in order to construct prototype plants for the Global Nuclear Energy Partnership. In this program and the Advanced Fuel Cycle Research and Development (AFC R&D) program that supports it, economic and environmental methods are being developed to reduce the impact of waste from commercial nuclear fuel cycles.

Recycling of used fuel by chemically separating it into U, fission products, and TRU would be the first step in this new …

Content-Based Video Classification And Comparison, John Alexander Bunch

UNLV Retrospective Theses & Dissertations

Automatic video analysis tools have dramatically increased in importance as the Internet video revolution has blossomed. This thesis presents an approach for automatic comparison of videos based on the inherent content. Also, an approach for creating groups (or clusters) of similar videos from a large video database is given; First, methods simplifying and summarizing the content of videos will be presented. Such methods include shot boundary detection and key frame feature extraction; Next, a comparison of different distance measures between videos will be given. These distance measures will be used to construct video clusters, and results will be compared.

T-Theory And Analysis Of Online Algorithms, James Oravec

UNLV Retrospective Theses & Dissertations

Several advancements in Online Algorithms can be credited to T-theory, a field of discrete mathematics. T-theory has aided in the development of several online algorithms for the k-server problem, although the standard notation of T-theory was not used at the time of their creation; A summary of the k-server problem, and some important concepts of T-theory, are given. A number of known k-server results are restated using the established terminology of T-theory. Included is a 3-competitiveness proof, using T-theory, for the HARMONIC algorithm for two servers, which was presented in a paper by Larmore and Oravec [71]; Previously, the Knowledge …

A Diffusion Model Of Lightning Radiative Transfer Using Cylindrical Geometry, Rina Alfonso Santos

UNLV Retrospective Theses & Dissertations

Clouds come in different shapes and sizes and are made up of different constituents. Realistic clouds are composed of heterogeneous distribution of constituents (ice particle, needle shaped objects, cubic, hexagonal, etc.). For tractability of solutions and smoothness of calculations, assumptions are made. The assumption is viable due to multiple scattering effect for propagation of radiation in random media. In Koshak et al. (1994), "Diffusion Model for Lightning Radiative Transfer", the cloud was treated as a nuclear reactor in order to obtain forms that can be readily computable and a simple geometry was chosen, i.e., a homogeneous rectangular parallelepiped Cloud In …

Tensile Deformation, Toughness And Crack Propagation Studies Of Alloy 617, Vikram Marthandam

UNLV Retrospective Theses & Dissertations

Austenitic nickel-base Alloy 617 has been tested under tensile loading at temperatures relevant to both the Nuclear Hydrogen Initiative and the Next Generation Nuclear Plant programs of the U.S. Department of Energy. Two important metallurgical phenomena, namely dynamic strain aging (DSA) and yield strength anomaly (YSA), have been identified based on the resultant data. DSA was characterized by reduced plastic strain and serrations in the engineering stress versus engineering strain diagrams. YSA was manifested by enhanced yield strength at relatively higher temperatures. A mechanistic understanding of DSA and YSA phenomena has been developed based on the estimation of dislocation density, …

Time-Optimal Control For One Dimensional Evacuation System, S. Wadoo, Pushkin Kachroo

Electrical & Computer Engineering Faculty Research

This paper presents design of a time-optimal controller for a model representing evacuation dynamics in one dimension. The model presented here is based on the law of conservation of mass. The model is the classical one equation model for a traffic flow based on conservation of mass with a prescribed relationship between density and velocity. The equations of motion are described by nonlinear partial differential equations. We address the optimal control problem for the space discretized dynamics thus making use of nonlinear ordinary differential equations. The objective is to synthesize a nonlinear open loop controller that evacuates people in minimum …

Urban Sustainability Through Green Building, Andrea Anzalone, Virginia Sawyer, Robert Woolsey

UNLV Theses, Dissertations, Professional Papers, and Capstones

This analysis is presented on urban sustainability through the use of "green building" in the City of Las Vegas, Nevada. This paper discusses the current practices used by the City of Las Vegas and compares them to the top 5 sustainable cities throughout the United States (as identified by the U.S. Green Building Council). Through comparison of nationwide initiatives and policies, this paper outlines recommendations the City of Las Vegas can adopt to increase their position as one of the leading sustainable cities.

Cooperative Conservation: Increasing Capacity Through Community Partnerships -- Interagency Volunteer Program: Quarterly Progress Report, Period Ending December 31, 2006, Margaret N. Rees

Get Outdoors Nevada

• Volunteer database increased 8% over last quarter. Database now contains 2,923 records.
• Website activity increased, recording an average of 51,568 hits per month, with an average of 4,985 pages viewed per month (12.4% increase in pages viewed).
• Team charter approved and signed by federal managers and IVP team.
• Volunteer orientation and training in 11 subject areas delivered to 80 volunteers.
• Recognition Banquet and Awards Ceremony recognized 180 volunteers.
• Volunteer event list revised for 2007.

Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Final Close-Out Report, Margaret N. Rees

Oliver Ranch Project

“The mission of the Red Rock Desert Learning Center is to instill stewardship and respect by increasing knowledge and understanding of the Mojave Desert ecosystems and cultures through a unique experiential discovery program.”

Interagency Science And Research: Quarterly Progress Report, Period Ending December 31, 2006, Margaret N. Rees

Interagency Science and Research Strategy

• Completed draft review and analysis of 6 interagency and 2 single-agency science strategies.
• Developed an outline for a Southern Nevada Agency Partnership Science Strategy based upon these reviews.
• Initiated a beta-test of a science proposal review process.

Lake Mead National Recreation Area Vegetation Monitoring And Management: Quarterly Progress Report, Period Ending December 31, 2006, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• Two new Weed Sentry research assistants were hired.
• Weed Sentry staff surveyed for exotic species on 89 miles of roads on NPS and BLM land and treated more than 21,000 exotic plants in incipient populations.
• A grid-based rare plant monitoring method was tested this quarter.
• A manuscript detailing vegetation succession on a water pipeline at Lake Mead NRA was submitted for review to the journal Crossosoma.
• New integrative projects undertaken this quarter included establishing a competition study between a native grass and the exotic Sahara mustard, salvaging plants for research purposes from private sites with permission from landowners, …