Digital Commons Network^™

Photoelectron Spectroscopy And The Dipole Approximation, Oliver Hemmers, Dennis W. Lindle

Environmental Studies Faculty Publications

Over the past three decades, the dipole approximation has facilitated a basic understanding of the photoionization process in atoms and molecules. Advances in gas-phase photoemission experiments using synchrotron radiation have recently highlighted nondipole effects at relatively low photon energies while probing the limits of the dipole approximation. Breakdowns in this approximation are manifested primarily as deviations from dipolar angular distributions of photoelectrons. Detailed new results demonstrate nondipolar angular-distribution effects are easily observable in atomic gases at energies well below 1 keV, and, in molecules, a previously unexpected phenomenon greatly enhances the breakdown of the dipole approximation just above the core-level …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase I, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells and buffered chemical polishing produce good performance. The objective of the proposed research is to maximize the performance of the niobium cavities through studying multipacting, studying the effect of chemical etching on the surface roughness, and redesigning the cavities.

The US Congress has recently authorized exploring an alternative way to deal with spent nuclear fuel: Accelerator Transmuting of Waste (ATW). In this approach, a particle accelerator produces protons that react with …

Experimental Investigation Of Steel Corrosion In Lead Bismuth Eutectic (Lbe): Characterization, Species Identification, And Chemical Reactions, John Farley, Dale L. Perry

Transmutation Sciences Materials (TRP)

The goal of the present research is to achieve a basic understanding of corrosion of steels by Lead Bismuth Eutectic (LBE). Liquid LBE is under consideration in the transmuter as both a coolant and a target material. There have been studies of LBE, especially by the Russians, but a fundamental understanding and verification of its role in the corrosion of steels is still very 2 incomplete. Post-experiment testing and analysis will be performed on steel samples that have been in intimate contact with LBE. Chemical alterations and resulting chemical species will be measured at the steel surface. Techniques to be …

The Procedure For Determining And Quality Assurance Program For The Calculation Of Dose Coefficients Using Dcal Software, A. Arndt, John P. Shanahan, C. Gold, R. Brey, T. Gesell, Phillip W. Patton, Mark Rudin, K. Eckerman, V. Rusetski, S. Pagava

Transmutation Sciences Physics (TRP)

The development of a spallation neutron source with a mercury target may lead to the production of rare radionuclides. The dose coefficients for many of these radionuclides have not yet been published. A collaboration of universities and national labs has taken on the task of calculating dose coefficients for the rare radionuclides using the software package: DCAL. The working group developed a procedure for calculating dose coefficients and a quality assurance (QA) program to verify the calculations completed. The first portion of this QA program was to verify that each participating group could independently reproduce the dose coefficients for a …

Perceptions Of Standards -Based Reform And The Role Of Instructional Leadership, Robert Bruce Anderson

UNLV Retrospective Theses & Dissertations

The purpose of this study was to increase the knowledge about science teachers' and principals' perceptions regarding science standards-based reform efforts in Nevada. The intent of the Nevada Education Reform Act (NERA) was to improve teaching and learning by impacting the following categories: (a) instruction, (b) assessment, (c) accountability, (d) professional development, (e) curriculum, and (f) supervision. The study investigated science teachers' and principals' perceptions of how standards impacted these areas as well as the role of instructional leadership in the implementation of standards-based reform. Finally, the study investigated how perceptions differed based on school size; This study employed what …

Factors Affecting Enrollment And Retention At The Church Of Jesus Christ Of Latter -Day Saints St George Institute Of Religion, John Savage Naegle

UNLV Retrospective Theses & Dissertations

The purpose of this research was to identify those factors that influence the decision of young, single, adult members of The Church of Jesus Christ of Latter-Day Saints ages 18--30 to be involved or not in the institute program; For Institutes to be effective in their charge to involve all young, single adults it would be helpful to understand why potential Institute students do one of the following: (1) Enroll in and complete an institute class. (2) Enroll in and stop attending an institute class. (3) Do not enroll in an institute class; Because the Church Educational System was asked …

A Descriptive Study Of The Organizational Culture And Structure Of Accelerated Schools, Susan Virginia Steaffens

UNLV Retrospective Theses & Dissertations

The purpose of this study was to survey teachers at five accelerated schools in the Clark County School District to determine their perceptions of the organizational culture and properties of their respective schools, and to determine if there are any differences between the results on these surveys and the original studies; Two instruments, the Organisational Culture Assessment Inventory (OCAI) and the Structural Properties Questionnaire (SPQ), were administered in the Spring of 2001 to 277 teachers from five selected accelerated schools in the Clark County School District. This resulted in a response rate of 35%. The stories and metaphors obtained from …

Development And Validation Of An Instrument For Student Evaluation Of Web -Based Instruction, Ingrid Stewart

UNLV Retrospective Theses & Dissertations

The current study attempted to develop an instrument to be used by instructors to conduct a comprehensive Web-based course evaluation. Four phases of instrument development were implemented. Phase I, involved the development if items through a review of the literature and the opinions of instructors and students enrolled in four Web-based mathematics courses. After the items were formulated and a response format was established, a questionnaire blueprint was developed. An item review, a content validation study, and an item tryout were conducted; In Phase II, the initial questionnaire was placed on the World Wide Web together with a cover letter …

Postmodern American Sociology: A Response To The Aesthetic Challenge, Jongryul Choi

UNLV Retrospective Theses & Dissertations

Over the past two decades, American sociologists have debated about the postmodern and what we might call "postmodern American sociology" began to emerge at the turn of this century. This dissertation examines the nature of the postmodern in general, and postmodern American sociology in particular, in terms of three models of knowledge: science, morality, and aesthetics; This dissertation pays close attention to the fact that science, morality, and aesthetics began to be differentiated from religion in the modern era, which posited two problems: the problem of legitimacy of knowledge and the problem of figuring out the relationship among science, morality, …

Instructional Differentiation In General Education And The Gifted Resource Room: Teacher And Student Perceptions, Mary Trombatore Greene

UNLV Retrospective Theses & Dissertations

This study compared the perceptions of three groups concerning differentiated educational opportunities provided for students with gifts and talents. The perceptions of general education teachers, gifted resource room teachers, and students with gifts and talents were collected using a questionnaire that encompassed questions focused on cognitive, interpersonal, and intrapersonal skill development; Results indicated that gifted resource room teachers and general education classroom teachers perceived that they provided differentiated instruction more often in the cognitive and interpersonal domains than in the intrapersonal domain. The most frequent differentiated instructional practices used by teachers (general education and gifted resource room) were in the …

A Comparative Study Of Funding Mechanisms For Community Colleges In The State Of Nevada And Selected States, Christopher Pat Kelly

UNLV Retrospective Theses & Dissertations

The purpose of this dissertation was to compare the mechanism utilized by the State of Nevada to fund its community colleges with the models used by other selected states to fund their two-year institutions. The comparison states that were chosen represented peer institutions of Nevada community colleges or systems held in high regard by the American Association of Community Colleges; These selected states, as well as Nevada, face difficult fiscal challenges funding their two-year colleges. Not only is there increasing competition for limited state resources, but virtually all of the states are projecting budget shortfalls due to the slowing economy; …

A Study Of Allied Health Care Entry -Level Employee Workplace Basic Skills And Competencies, Mildred Arroyo Mcclain

UNLV Retrospective Theses & Dissertations

This study utilized quantitative research methodologies to investigate the perceptions of Nevada allied health care providers regarding the importance of the workplace basic skills and competencies identified by the United States Department of Labor Secretary's Commission on Achieving Necessary Skills (SCANS,1991). Since it was assumed that employers possess direct knowledge of their employees' work skills, a questionnaire was developed and distributed to allied health care department supervisors in all of the identified hospitals within the state of Nevada; A primary purpose of this study was to determine the extent to which allied health care providers in Nevada considered each of …

Numerical And Experimental Investigation Of Deformation And Strength Properties Of Lithophysae -Rich Tuff And Analog Materials, Bahri Burcin Avar

UNLV Retrospective Theses & Dissertations

Portions of the high-level nuclear waste repository in Yucca Mountain will be located in lithophysae-rich tuff formations. Understanding the mechanical properties of the lithophysae-rich tuff, including deformation modulus, deformation ratio and compressive strength, is an important issue for design and the performance of the repository tunnels. These properties are expected to be significantly affected by lithophysal porosity; Two different research directions are implemented in this dissertation. First, uniaxial compression testing is simulated using finite difference technique on models containing circular holes in order to investigate the effect of porosity on deformation parameters. Numerical results are compared with biaxial test results …

Questions And Conjectures About Multinomial Coefficients, Troy Richard Kessler

UNLV Retrospective Theses & Dissertations

The purpose of this thesis is to try to answer some of the questions in Dr. Bachman's paper "On Divisibility Properties of Certain Multinomial Coefficients". First we let {ai} be any sequence (finite or infinite) of positive integers such that i1ai ≤1 . It is clear that n!&sqbl0;na1 &sqbr0;!&sqbl0;na2&sqbr0; !&sqbl0;na3&sqbr0;!&ldots; is an integer because it is a multiple of a certain multinomial coefficient. We let fan=n! Ln&sqbl0;n a1&sqbr0;!&sqbl0;na 2&sqbr0;!&sqbl0;na3 &sqbr0;!&ldots; where L(n) = lcm(1, 2, 3, .., n). It is easy to show that fa(n) is integer-valued. In particular, we would like to study the sequence a1 = b1 = …

Anomaly Detection In Hyperspectral Signatures Using Automated Derivative Spectroscopy Methods, Srilatha Panchanathan

UNLV Retrospective Theses & Dissertations

The goal of this research was to detect anomalies in remotely sensed Hyperspectral images using automated derivative based methods. A database of Hyperspectral signatures was used that had simulated additive Gaussian anomalies that modeled a weakly concentrated aerosol in several spectral bands. The automated pattern detection system was carried out in four steps. They were: (1) feature extraction, (2) feature reduction through linear discriminant analysis, (3) performance characterization through receiver operating characteristic curves, and (4) signature classification using nearest mean and maximum likelihood classifiers. The Hyperspectral database contained signatures with various anomaly concentrations ranging from weakly present to moderately present …

An Assessment Of Financial Ratios As Predictors Of Casino Stocks' Behavior, Flavia Godoy Razuk

UNLV Retrospective Theses & Dissertations

The purpose of this research is to assess the effectiveness of financial ratios as predictors of casino stocks' performance. The financial ratios used in this study were EBITDA/sales, adjusted EBITDA/shares, asset turnover ratio, current ratio, and debt/equity ratio. A regression analysis tested the correlation between the percentage changes in the financial ratios and the percentage change in the E/P ratio. In addition, a regression analysis tested the correlation between the percentage changes in financial ratios and the percentage change in the market capitalization of the companies in the sample. The statistical test used was a multiple regression analysis; The findings …

Multi-Object Recognition And Retrieval Using Puma560 Robot, Bharatha R Viswanadha

UNLV Retrospective Theses & Dissertations

The objective of the research described here is to develop efficient algorithm and software tools for multiobject recognition and retrieval. This research project addresses two major issues: The first issue is the identification of features and efficient methods for feature extraction which can completely describe an object. These features can be acquired using visual and ultra-sonic sensors. The second issue is the development of efficient algorithms for the retrieval of multi-objects based on their features; The methods and algorithms developed in this research are verified on a Unimation PUMA 560 robot. Non contact sensors (a vision and a range sensor) …

Image Interpolation And Denoising In Discrete Wavelet Transform Domain, Shaojie Wu

UNLV Retrospective Theses & Dissertations

Traditionally, processing a compressed image requires decompression first. Following the related manipulations, the processed image is compressed again for storage. To reduce the computational complexity and processing time, manipulating images in the transform domain, which is possible, is an efficient solution; The uniform wavelet thresholding is one of the most widely used methods for image denoising in the Discrete Wavelet Transform (DWT) domain. This method, however, has the drawback of blurring the edges and the textures of an image after denoising. A new algorithm is proposed in this thesis for image denoising in the DWT domain with no blurring effect. …

Oasis Deluxe, John M Ziebell

UNLV Retrospective Theses & Dissertations

This creative dissertation, submitted for partial fulfillment of requirements for the Master of Fine Arts (MFA) in Creative Writing degree, is a novella-length work of fiction set in Las Vegas, Nevada. My aesthetic intent was to construct a contemporary story around an unobtrusive but directive narrative voice that privileges multiple perspectives while uniting them into a coherent whole, and I hope the spirit of that goal is recognizable in the final product; While this work is not cumulative in terns of content, it does represent a narrative and structural sensibility I have developed during my years of study at this …

Construction Of A Random Signal With A Specific Psd And A Uniform Pdf, Venkatraghavan V Bringi

UNLV Retrospective Theses & Dissertations

The performance of a dynamic element matching (DEM) flash digital to analog converter (DAC) can be improved by controlling the DEM DAC's interconnection network with a random signal that has a specific power spectral density (PSD) and a uniform probability distribution function (PDF). Many algorithms exist for generating a random signal with a white PSD and a uniform PDF, but there exists only one algorithm for generating a random signal with a specific PSD and a particular PDF. For DEM DAC applications, the random signal must be generated at the speed of the DEM DAC. However, a real time implementation …

Testing The Potential Of System Dynamics Models For Improving Public Participation In Resource Management, Sarah Williams Cloud

UNLV Retrospective Theses & Dissertations

This thesis describes and discusses research which proposes that a system dynamics based-workshop can promote meaningful public participation in the resource management decision making process. The research tested the effectiveness of a system dynamics computer model for: (1) improving communication about technical data and stakeholder views; (2) increasing learning and insight into resource management issues; and (3) enhancing public trust in the decision making process. Seven research workshops were conducted to test the effectiveness of the model-based workshop for facilitating public participation in the management of the Las Vegas, NV water system. Workshop analysis showed that the system dynamics-based approach …

Assessing Learning Outcomes In College Introductory Economics Courses: A Case Study, John Richards Mundy

UNLV Retrospective Theses & Dissertations

Many issues affecting economic education remain unresolved within the profession. Much scholarly attention in recent years relates to the teaching of college introductory economics principles in courses. This thesis analyzes the learning outcomes of students taking introductory college economics principles courses. Little basic research has been performed on the assessment of how students actually learn the concepts of economics. This thesis takes a unique approach to the assessment of learning outcomes. Following a pre- and post-test survey, students were scored on the basis of both their economic attitude sophistication, and their knowledge of content. The results were regressed against a …

Evaluation Of In Situ Biodegradation Of Perchlorate In A Contaminated Site, Zhong Zhang

UNLV Retrospective Theses & Dissertations

This thesis investigated parameters affecting perchlorate biodegradation in the Las Vegas Wash area in Las Vegas, NV. Perchlorate is known to interfere with the functioning of the thyroid gland of humans. Perchlorate concentrations along the Las Vegas Wash were found to range from zero to 1000 ppb, while perchlorate concentrations in the contaminated seepage were approximately 100 ppm. Microbial counts in 30 water samples from the Las Vegas Wash and the contaminated seepage indicated that indigenous perchlorate-reducing microbes are ubiquitous and present in reasonable numbers. In the contaminated area, natural perchlorate biodegradation seems to be limited by at least three …

Mathematical Models For Interendothelial Cleft, Bin Chen

UNLV Retrospective Theses & Dissertations

Vascular endothelium is the principal barrier to, and regulator of, material exchange between circulating blood and the body tissues. Based on previous research in this field, two new theoretical models have been developed in this thesis. One is to investigate structural mechanisms in the regulation of microvessel permeability by cAMP. The other is to examine the charge effects of surface glycocalyx on microvessel permeability; To investigate the microstructural mechanisms of decreasing microvascular permeability induced by the enhancement of intraendothelial adenosine 3 ',5'-cyclic monophosphate (CAMP) levels, we extended the previous analytical model developed by Fu et al. (1994) for the interendothelial …

The Dichotomy In The Determinacy Of Certain Two-Person Infinite Games With Moves From {0,1}, Deborah Sue Fraker

UNLV Retrospective Theses & Dissertations

We investigate certain well-known games from the field of set theory; namely, certain two-person games of perfect information with small complexity and with small infinite length. We consider games with moves from the natural numbers and games with moves from {0,1}. We show that the determinacy of open games with length o·n and with moves from {0,1} is true regardless of the existence of large cardinals for n ≥ 2. We show that this is not true, however, for some more complex games: For k ≥ 3 and n ≥ 2, the determinacy of P0k games with length o·n and …

Estimating Effective Discharge At Lehman Creek, Great Basin National Park, Nevada, Lisa A Glonek

UNLV Retrospective Theses & Dissertations

Effective discharge is defined as the streamflow that transports the most sediment over time and is therefore the flow that controls channel shape. Effective discharge was estimated for two sites along Lehman Creek, an alpine fluvial system. Site one (WL-1, 2951 m elevation) has an effective discharge of 0.083 m3/s and site two (WL-2, 2019 m elevation) has an effective discharge of 0.400 m3/s. Calculated bankfull discharges are 2.52 m3/s for WL-1 and 1.48 m3/s for WL-2. Bankfull/effective discharge ratios (b/e ratio) are 30.49 for WL-1 and 3.71 for WL-2. The b/e ratio difference may be due to the steeper …

Analysis Of The Crash Potential At Signalized Intersections With Trap Lanes, Joanna Kajkowski

UNLV Retrospective Theses & Dissertations

The purpose of this thesis was to evaluate how significantly a trap lane may influence the crash potential at signalized intersections. Field and historical data from fifty-four locations within the Las Vegas Metropolitan Area were used for the analysis. Bivariate and subset linear regression analyses were used to evaluate the relationship of several predictor variables to three dependent variables using two data sets. The dependent variables are stated below. (1) Sideswipe Crashes per Total Crashes; (2) Total Upstream Crashes per Total Crashes; (3) Total Crashes per AADT/10,000 per Intersection Lane Overall, the results of the analysis do not strongly support …

Diagnostic Test And Analytical Methods For Resolving Fan/Motor Vibration Problems In Air-Conditioning Units, Qin Liu

UNLV Retrospective Theses & Dissertations

The objective of this thesis is to develop test and analysis procedures to revise ASHRAE Standard 87.1 Standard for small (<36 in. diameter) propeller fans. Test and analysis procedures also need to be used to convert AHRAE Standard 87.1 - 1992 test results where the fan hub mobility is zero to corresponding results that will exist with a finite (nonzero) hub mobility; In this project, the vibration modes of a fan with three cambered blades were investigated. Experimental and Finite Element Analysis (FEA) was performed on the fan blade and the fan-motor unit. The project compared the results obtained from the FEA and experimental modal analysis of the fan assembly. A very good correlation between FEA and the experimental modal analysis was found.

Effects Of Ocr Errors On Text Categorization, Lidija K Mackovski

UNLV Retrospective Theses & Dissertations

In this thesis; we report on our experiments on training and categorization of optically recognized documents. In, particular, we present a lexicon-based error correction algorithm to improve the categorization process. This algorithm is based on edit distance techniques and information from highly weighted words in the categorizers.

An Examination Of Mentoring Among Graduate Teaching Assistants, Kimberly Kay Nehls

UNLV Retrospective Theses & Dissertations

Mentoring is a communication process where an experienced guide helps a novice adjust to new surroundings. The goal is to assist newcomers with difficult transitions. The literature review determined that mentoring has recently evolved to academia with a desire to aid students and faculty. A need arose to examine peer communication between graduate students. This study specifically examined peer mentoring among graduate teaching assistants (GTAs) at the University of Nevada, Las Vegas. Surveys were distributed to GTAs in every department and school at that university. Results indicated that GTAs believe the teaching experience has been good for them, but responded …