Digital Commons Network^™

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 …

Evaluation Of Geophysical Methods To Characterize Alluvial Soils In The Arid Environment, Bjorn E Sundquist

UNLV Retrospective Theses & Dissertations

Non-intrusive geophysical investigations, both seismic and electrical, were performed at several locations on the Las Vegas Springs Preserve in Las Vegas, Nevada, along with intrusive drilling. These investigations were conducted to determine whether it is possible use geophysical methods to detect piping-induced cavities and shallow inclusions such as calcific nodules and horizons known as caliche in dry, desert soil, while at the same time characterizing the mechanical structure of the soil and distribution of soil moisture for engineering purposes. The geophysical methods used were the Spectral-Analysis-of-Surface-Waves (SASW) method, surface-based seismic cavity detection, multi-electrode electrical resistivity, and electromagnetic conductivity. The results …

An Evaluation Between Confidence Judgments And Differences In Monitoring Ability, Brett Douglas Campbell

UNLV Retrospective Theses & Dissertations

Metacognition is the awareness of a person's thinking and the ability to regulate that thinKing This study examines how confident a person is at monitoring progress during two cognitive tasks. The fast task was the feeling-of-knowing paradigm, when participants judge how accurately they can retrieve an answer in a recognition task, when they cannot retrieve the answer in free recall. The second task was a paired-associate interference paradigm. Participants were presented with a list of noun-noun pairs twice and then a new list was presented for recall. Participants were placed into three groups (high, medium, low) based on responses to …

Complexity: Theoretical And Methodological Applications For Sociology, Kathryn A Gilpatric

UNLV Retrospective Theses & Dissertations

This thesis examines the usefulness of Complexity as a new tool for sociology. Complexity, as its own branch of study, developed from the new science of Chaos. Recent paradigmatic disputes occurring in the scientific community have been the force of a growing sense of change in the way many different disciplines view complex systems. Since it is evident that social systems are typically highly complex, it makes sense that a scientific paradigm, which investigates the nature of complex systems, should also be applicable to social systems. Science now argues that the old Newtonian clockwork mentalities and classical experimental models cannot …

The Impact Of A 185-Mill Deduct As An Equalization Factor In The North Dakota Foundation Aid Formula, Michael A. Bitz

Theses and Dissertations

No abstract provided.

Durango Hills Water Resource Center, City Of Las Vegas, Nevada

Publications (WR)

No abstract provided.

Meeting Scheduling System (Mss), Mun Ting Ng

Student Works (2000-2009)

Meeting Scheduling System (MSS) is a web-based system developed to support the organization of meetings, that is for each meeting request, a suitable meeting date can be determine based on constraints like meeting location, equipment and the number of invitees that can attend the meeting. Besides that, Meeting Scheduling System (MSS) allow users to check if the invitees are available to attend a meeting, and will inform participants on details about meetings tl1at involve them. It is to avoid the possibility of scheduling a person to attend two or more meetings at one time. Other than that, Meeting Scheduling System …

Esc/Gel 1300g : Introduction To Earth Sciences, Geology/Geography

Approved Course Proposals

No abstract provided.

Chm 1301g : General Chemistry I, Chemistry

Approved Course Proposals

No abstract provided.

Bio 1002g : Practical Botany, Biological Sciences

Approved Course Proposals

No abstract provided.

Esc/Gel 3010g : Environmental Physical Science, Geology/Geography

Approved Course Proposals

No abstract provided.

Analysis Of A Class Of Integro -Differential Equations Describing Age Dynamics Of A Natural Forest, Michael A. Kraemer

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Ultrafast Nonlinear Spectrometer For Material Characterization, Raluca A. Negres

Retrospective Theses and Dissertations

This work describes the use of a broadband spectral source for nonlinear spectroscopy to characterize various materials with potential applications in confocal microscopy, biological sample markers, optical limiting devices and optical switches. The goal is to study the spectrum of nonlinear absorption and the dispersion of nonlinear refraction as well as the dynamics of the nonlinearities by means of femtosecond excite-­probe experiments.

The principle is quite simple: if a sample is under the influence of a strong fs excitation pulse and a pro be pulse beam is incident at the same time, or shortly after (within the decay time of …

Some New Approaches To Formulate And Estimate Friction-Bernoulli Jump Diffusion And Friction-Garch, Chihwa Kao

Center for Policy Research

In this paper we propose a friction model with a Beroulli jump diffusion and a friction with GARCH to examine the exchange rates movements in Taiwan. The proposed model resolves the estimation problem associated with the stepwise movements of observed exchange rates. The specification maintains the desirable economic properties associated with movements in exchange rate returns and is empirically tractable. The AIC apparently favors the model based on Friction-GARCH model.

Optimal Estimation Of Nonlinear And Linear Parameters In General Linear Models, Supratim Saha

Open Access Dissertations

This dissertation primarily concerns maximum likelihood (ML) estimation of linear and nonlinear parameters in some class of general linear models (GLMs). We deal with problems which are directly expressible in GLM as well as the ones in which some manipulation is required to obtain a GLM. It is well known that the joint ML estimation of the linear and nonlinear parameters in a GLM leads to a multidimensional grid search. As closed form solutions do not exist, iterative techniques have been the only resort to avoid a multidimensional grid search. However iterative techniques are not guaranteed to converge. As a …

Enhancing Micro-Organism Images By Estimating Image Background, Delong Liu

Open Access Dissertations

One- and two-dimensional techniques are proposed for enhancing micro-organism images using linear least-squares fitting, median filtering combined with bicubic approximation and wavelet filtering, respectively. The quality of enhanced images with pixel dimensions of 1200 x 1600 is examined from their corresponding binary images. It shows that one-dimensional modeling requires much less computation but provides relatively low quality output. On the other hand, the two-dimensional approximations for non-uniform lighting background, using both bicubic spline and wavelet filtering, are more effective and yield very high quality binary images tested with three different grayscale images.

A Preliminary Assessment Of Tidal Flooding Along The New Hampshire Coast: Past, Present And Future, Larry G. Ward, Jamie R. Adams

Faculty Publications

This report presents the results of a preliminary study that examines several critical coastal issues for New Hampshire including sea level fluctuations (past, present and future), shoreline migrations, and tidal flooding. Included are: 1) an analysis of sea level changes over the Holocene and resulting shoreline migrations, 2) an assessment of low-lying areas with elevations below selected tidal flooding datums in coastal areas, and 3) an assessment of increases in low-lying areas that are potentially at risk to tidal flooding over the next century due to sea level rise.

A Study On The Effect Of Storage Time On Specific Gravity And Eggshell Quality, Brock Kendall Laborde

Honors Capstones

No abstract provided.

Constructing Regular Ramanujan Graphs Via Graph Extension, Sage Michelle Accardo

Honors Capstones

No abstract provided.

Models, Algorithms, And Measurements For Underwater Acoustic Positioning, Harold Thomas Vincent Ii

Open Access Dissertations

Several problems in underwater acoustic position estimation are investigated within the context of their associated models, algorithms, and measurements. The first appendix provides a detailed discussion of these concepts and demonstrates the fact that simultaneous consideration of all three is necessary in order to properly address a particular position estimation problem. The particular problems addressed herein stem from the so-called long baseline underwater acoustic positioning method whose principle of operation is hyperbolic multilateration; a technique employed in the now common Global Positioning System and its predecessor systems such as Long Range Navigation (LORAN), Decca and Omega. Although motivated by this …

Photoemission And Photo-Absorption Studies Of Ultrathin Iron Films On Copper(100) Oxidized At Elevated Temperature., Reginaldt Hamilton Madjoe

LSU Historical Dissertations and Theses

In this investigation, I have focused on understanding the structure and morphology of ultrathin iron oxide films and characterizing them by using LEED, photoemission (both angle-resolved and angle-integrated) and photoabsorption measurements. Fe films were deposited on a Cu(100) substrate at room temperature growing in a layer by layer fashion. The sample was then annealed to 810K in oxygen ambient. This oxidation process led to dramatic changes of the sample surface and electronic structure depending on initial Fe coverage. Half-metallic oxides such as CrO2 and Fe3O4 may provide opportunities for new magnetic devices since their single spin orientation at the Fermi …

Improved Matrix-Assisted Laser Desorption/Ionization Linear Time-Of-Flight Mass Spectrometry Of Oligonucleotides And Nucleic Acids Via Matrix Additives And Sample Preparatory Technique., Tracey Arlene Simmons

LSU Historical Dissertations and Theses

There are two prominent problems recurrent during matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis of oligonucleotides: cation adduction and low molecular ion stability. It has been found that the use of organic base solutions of high gas-phase proton affinity, as used previously in electrospray ionization mass spectrometry (ESI-MS), can significantly reduce the cation adduction problem during MALDI-MS. It is proposed that the organic base solutions compete with alkali metal cations for binding to the phosphodiester backbone of the oligonucleotide upon transfer into the gas phase. A comparison of the utility of adding an organic base solution, such as imidazole, triethylamine …

A Hierarchical Shape Representation By Convexities And Concavities And Its Application To Shape Matching., Gustavo Martinez

LSU Historical Dissertations and Theses

Shape contains information. The identification and extraction of this information is not straightforward and is the main problem of Shape Analysis. The current trend of manipulating visual information, makes this problem more important. The abundant work published about shape analysis can be classified into two main approaches: statistical shape analysis and structural shape analysis. The structural approach was proposed around thirty years ago by K. S. Fu. The large amount of works published since then, prove the difficulty of defining a universal set of primitives. The structural description of shape is based on the assumption that shape recognition is a …