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2005

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Characterization Of Alloy C-276 As A Structural Material For High-Temperature Heat Exchangers, Narendra V Kothapalli Jan 2005

Characterization Of Alloy C-276 As A Structural Material For High-Temperature Heat Exchangers, Narendra V Kothapalli

UNLV Retrospective Theses & Dissertations

This investigation was focused on characterizing the high-temperature tensile behavior and corrosion susceptibility of nickel-based Alloy C-276, a leading structural material for heat-exchangers in nuclear hydrogen generation. The tensile properties, evaluated at different temperatures, indicate that both the yield strength and ultimate tensile strength were gradually reduced with increasing temperature. However, the ductility parameters were not significantly influenced by the testing temperature. While no failures were observed in stress corrosion cracking (SCC) tests in an acidic solution under a constant-load, the true failure stress (sigmaf) was significantly reduced under a slow-strain-rate condition using both smooth and notched specimens. The critical …

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On Using Block Principal Component Analysis For Reducing Gene-Expression Data Dimensions, Sang Hee Lee Jan 2005

On Using Block Principal Component Analysis For Reducing Gene-Expression Data Dimensions, Sang Hee Lee

UNLV Retrospective Theses & Dissertations

Since a microarray gene expression database contains a large number of variables and a relatively small number of samples, using and analyzing the databases require an intense, large-dimension computation method. Principal component analysis (PCA) is a useful tool to reduce the number of dimensions, and therefore, the complexity. PCA allows us to analyze the gene expression database with a relatively small data dimension without losing relevant information and increases the analytic visibility of the data. The initial computation using PCA, however, involves calculating a high-dimension covariance or correlation matrix and requires time and hardware resources which are limited in most …

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Residence Choices Of Hispanic Neighborhoods In Nevada, Qiong Li Jan 2005

Residence Choices Of Hispanic Neighborhoods In Nevada, Qiong Li

UNLV Retrospective Theses & Dissertations

A well-known characteristic of Hispanic in the U.S. is their tendency to concentrate their settlement area in distinct locations. This study merges aggregate data of localities with micro observations to estimate the joint decisions of residential location and homeownership choice for Hispanics. To address the possibility that the disturbances in the regression may be correlated within groups, we apply a bivarite probit framework clustered by localities (PUMAs), using the Public Use Micro Statistics of Census 2000 data for Nevada. The results suggests that Hispanics choose to live in Hispanic enclaves are characterized by lower income, less English fluency, lower educational …

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Identifying Low-Carb Dieter's Characteristics And Their Diet Practices During Business Travels, So Jung Lee Jan 2005

Identifying Low-Carb Dieter's Characteristics And Their Diet Practices During Business Travels, So Jung Lee

UNLV Retrospective Theses & Dissertations

The low carbohydrate diet phenomenon has recently evolved to such an extent that there is now extensive consumer demand for carbohydrate conscious dining options. The power of the recent movement is impacting all facets of the hospitality industry including restaurants, hotels, airlines and conventions. The purpose of this study is to identify business travelers' low carbohydrate diet practices and to understand their experiences with low-carbohydrate menus during business trips; This research identified low-carb dieters' characteristics and their diet practices during business trips. Results indicated that, compared to other dieters, low-carb dieters are older, more likely to be overweight or obese, …

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Semi-Active Control Techniques For Shock Isolation, Ganesh B Maganti Jan 2005

Semi-Active Control Techniques For Shock Isolation, Ganesh B Maganti

UNLV Retrospective Theses & Dissertations

In this thesis the problem of control of semi-active devices (MR damper, MR elastomer) for shock isolation systems are considered. Semi-active control systems combine the best features of both the passive and active control systems, offering the reliability of passive devices, yet maintaining the versatility and adaptability of fully active devices. First the question of stability and control of a two degree-of-freedom magnetorheological (MR) fluid damper shock isolation system is considered. It is shown that for any arbitrarily time varying input current, the system is absolutely stable. This explains the shock isolation capability of the MR damper system even with …

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The Buildings At The Center: Latter-Day Saint Tabernacles In The Mormon Culture Region, Aaron James Mcarthur Jan 2005

The Buildings At The Center: Latter-Day Saint Tabernacles In The Mormon Culture Region, Aaron James Mcarthur

UNLV Retrospective Theses & Dissertations

Tabernacles are a largely overlooked feature of communities in the Mormon Culture Region. Though the tabernacle on Temple Square in Salt Lake City has world-wide recognition, very little has been written about the other 78 that the Church of Jesus Christ of Latter-day Saints built between 1847 and 1953. This thesis discusses the religious, cultural, and social motivations behind the planning and construction of tabernacles, as evidenced by developments such as the Plat of the City of Zion and the Priesthood Reorganization of 1877, as well as the numerous uses of these buildings. The significance of the buildings in the …

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Attitudinal And Behavioral Assessments Of Generations X And Y At The Palms Casino Resort, Ch-A Mosley Jan 2005

Attitudinal And Behavioral Assessments Of Generations X And Y At The Palms Casino Resort, Ch-A Mosley

UNLV Retrospective Theses & Dissertations

Las Vegas area casino hotels have recently begun to vie for the attention and business of Generations X and Y. This is evidenced by the influx of night clubs, lounges, and party-like pool scenes in Strip properties. The purpose of the study is to utilize the Palms Casino Resort's young adult clientele to determine what attributes they find appealing about it. The data garnered through primary empirical research revealed implications for potential marketing initiatives and future research. This project was both quantitative and qualitative in nature.

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Justifying The Plaintiff's Receipt Of Punitive Damages, Marlisa Moschella Jan 2005

Justifying The Plaintiff's Receipt Of Punitive Damages, Marlisa Moschella

UNLV Retrospective Theses & Dissertations

This thesis addresses the punitive damages reform issue of whether or not the plaintiff should receive the award. Reformers argue the purposes of punitive damages would be better served with other distribution options; and prioritized societal gains, above the gains of the plaintiff. The various purposes of punitive damages show that receipt by the plaintiff is in accordance with original intentions of punitive damages and serves justice. The historical and modern purposes of punitive damages such as vengeance satisfaction, redeeming honor, repairing insult, and supporting 'private attorneys general,' are maintained by the plaintiff receiving damages. These purposes provide an important …

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Dorsal And Pectoral Fin Control Of A Biorobotic Autonomous Underwater Vehicle, Mukund Narasimhan Jan 2005

Dorsal And Pectoral Fin Control Of A Biorobotic Autonomous Underwater Vehicle, Mukund Narasimhan

UNLV Retrospective Theses & Dissertations

This thesis involves an in-depth research on the maneuvering of bio-robotic autonomous undersea vehicles (BAUVs) using bio-mimetic swimming mechanisms. Motivation was derived from the amazing flexibility and agility the fish inherit with the help of their pectoral and dorsal fins; In the first part of the thesis, control of BAUVs using dorsal fins is considered. The force produced by the cambering of the dorsal fins is used for control. An indirect adaptive controller is designed for depth tracking along constant trajectories even when the system parameters are not known. Next, for following time-varying trajectories, an adaptive control system for yaw …

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Petrogenesis Of Extracaldera Rhyolites At Yellowstone Volcanic Field: Evidence For An Evolving Silicic Magma System North Of Yellowstone Caldera, Nicole Marie Nastanski Jan 2005

Petrogenesis Of Extracaldera Rhyolites At Yellowstone Volcanic Field: Evidence For An Evolving Silicic Magma System North Of Yellowstone Caldera, Nicole Marie Nastanski

UNLV Retrospective Theses & Dissertations

Rhyolites erupted at 526--80 ka north of Yellowstone Caldera may record the most recent migration of the Yellowstone melting anomaly, yet their relation to the magma system that produced caldera-forming eruptions at 2.1, 1.3, and 0.64 Ma was previously unclear. New petrographic, geochronology, and geochemical data show that 10 of 12 rhyolites define a spatially (Norris-Mammoth corridor), temporally (326--80 ka), and chemically related group derived from a single magma system independent of the caldera-related magma system. These data are consistent with the establishment of a magma system of substantial longevity (>200 ka) and long magma residence times (up to …

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Design And Control Of A Smart Fin Using Piezoelectric Actuators, Surya Kiran Parimi Jan 2005

Design And Control Of A Smart Fin Using Piezoelectric Actuators, Surya Kiran Parimi

UNLV Retrospective Theses & Dissertations

The objective of this research work is to design and implement control algorithms for smart fin of a projectile, which is currently under development in the Army Research Laboratory (ARL). The smart fin is used to maneuver small aerial vehicles by controlling the rotation angle of the fin. The fin is activated by a composite laminated plate that has two active piezoelectric layers. The prototype of the smart fin is assembled using Macro Fiber Composite (MFC actuator model M8557, Smart Material Co); Control algorithms for rotating the fin when subject to external aerodynamic forces are proposed. These controllers use a …

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Analysis Of Logic Block Architectures And Functional Improvement Of Fine Grained Cells, Rohith Ramnath Jan 2005

Analysis Of Logic Block Architectures And Functional Improvement Of Fine Grained Cells, Rohith Ramnath

UNLV Retrospective Theses & Dissertations

The first objective of this research project was to evaluate the performance of various logic block architectures in FPGAs. Since logic blocks widely vary in size, functionality and complexity, we were motivated to explore them in detail. For our study, logic blocks from Actel, Altera, Quicklogic and Xilinx were chosen along with some designs discussed in the academia. These cells were either multiplexer based or look-up-table (LUT) based. Structural VHDL models of all these blocks were constructed and benchmarks circuits were mapped. Results at this stage suggested that, although the coarse grained cells occupied more area and showed poor utilization, …

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The Method Of Fundamental Solutions For Solving Wave Equations, Lourdes Jeanette Rivera Jan 2005

The Method Of Fundamental Solutions For Solving Wave Equations, Lourdes Jeanette Rivera

UNLV Retrospective Theses & Dissertations

In recent years, the method of fundamental solutions (MFS) has emerged as a novel meshless method in the scientific computing community. In the past, the MFS was essentially restricted to solving homogeneous elliptic equations. Recently, the MFS has gradually extended to solving various types of elliptic and time-dependent problems through the uses of radial basis functions (RBFs); In this thesis, we focus on solving wave equations through the MFS. Currently, there are two major approaches to solve the wave equation: (i) elimination of the time dependence by using the Laplace transform and (ii) discretization in time to approximate the time …

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Gamma-Aminobutyric Acid Inhibits Interleukin-1beta Stimulated Release Of Interleukin-6 From Rat C6 Glioma Cells: In Vitro Evidence For A Role Of P38 Map Kinase, Raghuram Royyuru Jan 2005

Gamma-Aminobutyric Acid Inhibits Interleukin-1beta Stimulated Release Of Interleukin-6 From Rat C6 Glioma Cells: In Vitro Evidence For A Role Of P38 Map Kinase, Raghuram Royyuru

UNLV Retrospective Theses & Dissertations

We investigated the pathway of IL-1beta stimulated IL-6 release and the involvement of different MAPK's effectors. We used three different MAPK inhibitors SB203580 for p38, SP600125 for JNK, and PD98059 for ERK kinases. We described the role of gamma-Aminobutyric acid (GABA) and GABAB receptor in the inhibition of IL-1beta signal transduction; Bioassay results suggest that SB203580 inhibited IL-6 release while the other two MAPK inhibitors had no effect. It also suggested GABA inhibits the IL-1beta stimulated release of IL-6. By Western analysis we found that IL-1beta activated p38 MAPK time dependent fashion and we saw a maximum stimulation occurred at …

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Effect Of A High Protein Diet On Glucose Tolerance In Rats, Roxanne Mary Sanchez Jan 2005

Effect Of A High Protein Diet On Glucose Tolerance In Rats, Roxanne Mary Sanchez

UNLV Retrospective Theses & Dissertations

The purpose of this study was to determine the effects of a high protein diet on glucose tolerance in the rat model. Nine Sprague Dawley rats received a high protein diet (65% protein, 35% fat) and eight rats consumed a standard chow diet over the course of eight weeks. An oral glucose tolerance test (OGTT) was performed at the end of the third and the seventh week to measure blood glucose and plasma insulin concentrations. The diet did not effect glucose tolerance in the first OGTT (t = 1.2095, p = .1226) or the second OGTT (t = -.9855, p …

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Immobilization Of Fission Iodine By Reaction With Fullerene Containing Carbon Compounds Or Insoluble Natural Organic Matter, Gregory Tye Schmett Jan 2005

Immobilization Of Fission Iodine By Reaction With Fullerene Containing Carbon Compounds Or Insoluble Natural Organic Matter, Gregory Tye Schmett

UNLV Retrospective Theses & Dissertations

Since the start of the nuclear age, weapons testing and commercial nuclear power plants have been producing radioactive iodine-129 as a fission by-product. Iodine-131 has a half-life of 8 days and is generally not deemed a serious storage problem. Iodine-129 has a half-life of sixteen million years and decays by Beta emission; The Department of Energy (DOE) has determined there are three major contributors to public radiation dose as a consequence of radionuclides releases. The three isotopes of major concern for the DOE are iodine-129, technetium-99 and neptunium-237 (129I, 99Tc, 237Np). DOE has a research and development program called the …

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Development Of An Instrument Designed To Measure Student Perception Of School Connectedness, Nicole Jennifer Smith Jan 2005

Development Of An Instrument Designed To Measure Student Perception Of School Connectedness, Nicole Jennifer Smith

UNLV Retrospective Theses & Dissertations

The purpose of this study was to design and validate an instrument to measure student perception of school connectedness. The intended use for this instrument was to evaluate school-based health interventions such as "Planned Approach to Healthier Schools" (PATHS; Lounsbery, Gast, & Smith, 2005), and to potentially examine other important correlates of student perception of school connectedness, such as attendance in school, referral rates, as well as school drop out and graduation. The development of the instrument included a series of steps which comprised (a) identification of a purpose, (b) specification of an underlying theory, (c) item development, (d) content …

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Cfd Modeling Of Compact Offset Strip-Fin High Temperature Heat Exchanger, Sundaresan Subramanian Jan 2005

Cfd Modeling Of Compact Offset Strip-Fin High Temperature Heat Exchanger, Sundaresan Subramanian

UNLV Retrospective Theses & Dissertations

This thesis deals with the development of a numerical model to predict the overall performance of an advanced high temperature heat exchanger (HTHX) design, up to 1000°C, for the production of hydrogen by the sulfur iodine thermo-chemical cycle. The present study considers an offset strip-fin type compact high temperature heat exchanger made of liquid silicon impregnated carbon composite (SiC). The ceramic matrix composite material (CMC) is manufactured by impregnating the silicon into the pores of the carbon composites. The prototype heat exchanger is designed to operate at a thermal power of 50 MW. The design is an offset strip-fin, hybrid …

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Millipede: A Graphical Tool For Debugging Distributed Systems With A Multilevel Approach, Erik Helge Tribou Jan 2005

Millipede: A Graphical Tool For Debugging Distributed Systems With A Multilevel Approach, Erik Helge Tribou

UNLV Retrospective Theses & Dissertations

Much research and development has been applied to the problem of debugging computer programs. Unfortunately, most of this effort has been applied to solving the problem for traditional sequential programs with little attention paid to the parallel and distributed domains. Tracking down and fixing bugs in a parallel or distributed environment presents unique challenges for which these traditional sequential tools are simply not adequate. This thesis describes the development and usage of the Millipede debugging system, a graphical tool that applies the novel technique of multilevel debugging to the distributed debugging problem. By providing a user interface that offers the …

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Islanding Issues Associated With Photovoltaic Inverters, Ramachandran Tripunithura Mahadeva Jan 2005

Islanding Issues Associated With Photovoltaic Inverters, Ramachandran Tripunithura Mahadeva

UNLV Retrospective Theses & Dissertations

One of the main barriers for the proliferation of photovoltaic (PV) systems in power distribution networks is the concern over possible islanding, i.e., when a disconnected part of the power network remains energized by the connected PV systems for a significant time interval. Islanding is undesirable for a number of reasons including safety hazards to utility personnel; and potential damage to equipment. Numerous anti-islanding techniques have been proposed and implemented in present-day grid-tie inverters. This thesis reviews some of the pros and cons of different anti-islanding techniques, and offers a solution to the Multiple Inverter Islanding Issue and also presents …

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The Role Of Applied Potentials On Cracking Of Zircaloy-2, Unnikrishnan Valliyil Jan 2005

The Role Of Applied Potentials On Cracking Of Zircaloy-2, Unnikrishnan Valliyil

UNLV Retrospective Theses & Dissertations

Consistent with the earlier observation, this investigation revealed that Zircaloy-2 (Zr-2) may exhibit enhanced ductility at elevated temperature when tested under the combined effect of applied stress and an acidic environment. Since the cracking susceptibility of Zr-2 may be influenced by applied potentials, SCC tests were performed in a similar environment under cathodic and anodic controlled potentials (Econt). While the effect of cathodic Econt was insignificant, Zr-2 exhibited enhanced cracking susceptibility when tested under an anodic Econt. The localized corrosion study using cyclic polarization indicates that the critical potentials became more active with increasing temperature. Secondary cracks were noted in …

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Sociability And "Survivor", Shelley Elizabeth Wilkerson Jan 2005

Sociability And "Survivor", Shelley Elizabeth Wilkerson

UNLV Retrospective Theses & Dissertations

Reality television, and the program Survivor in particular, have quickly become a powerful social force in Europe and America. The author explored the possibility that Survivor audience members use and obtain gratifications from the program that increases, or enhances, their sociability. Uses and Gratifications Media Theory was used to determine why reality programs in general are watched; Results indicated that some viewers may use the program Survivor as a social tool, but these viewers were not necessarily non-social to begin with. Results also indicated that the reasons why viewers choose to watch reality programming are surprisingly similar across the genre.

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Business Failure Prediction For Korean Lodging Firms Using Multiple Discriminant Analysis And Logit Analysis, Hyewon Youn Jan 2005

Business Failure Prediction For Korean Lodging Firms Using Multiple Discriminant Analysis And Logit Analysis, Hyewon Youn

UNLV Retrospective Theses & Dissertations

This study makes an attempt to develop business failure prediction models for lodging firms located in South Korea using multi-variate analyses. These multi-variate analyses include Multiple Discriminant Analysis (MDA) and logit analysis. This study looked at the financial statements from a total of 154 firms to develop the prediction models, and used 11 different financial ratios from liquidity, solvency, leverage, and efficiency categories as classifying variables. The descriptive statistics of the 11 ratios for the failed and non-failed groups indicated that non-failed hospitality firms were significantly better than failed hospitality firms in terms of liquidity, leverage, and solvency, demonstrating the …

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Effects Of Attentional Focus On Kinematics And Muscle Activation Patterns As A Function Of Expertise, Tiffany L Zachry Jan 2005

Effects Of Attentional Focus On Kinematics And Muscle Activation Patterns As A Function Of Expertise, Tiffany L Zachry

UNLV Retrospective Theses & Dissertations

It has been demonstrated that for motor tasks, an external focus of attention can yield better results than an internal focus of attention. To be more specific, focusing on the effect of the movements seems to be more beneficial to performance and learning than focusing on the movements themselves (for a review, see Wulf & Prinz, 2001). To explain this phenomenon, Wulf, McNevin, and Shea (2001) proposed that an internal focus of attention is less effective because concentrating on the movements interferes with the motor system's attempt to naturally self-organize, the "constrained-action hypothesis." The purpose of this study was to …

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Thermal Comfort In Office Buildings, Lalith Sandeep Annavarapu Jan 2005

Thermal Comfort In Office Buildings, Lalith Sandeep Annavarapu

UNLV Retrospective Theses & Dissertations

The Department of Energy (DOE), the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) and other government agencies and professional associations which are interested in to the building industry have initiated policies and developed methods to reduce energy consumption in buildings. Policies and methods designed to reduce energy usage in buildings have had significant impacts on building performance characteristics and indoor air quality and environmental conditions. These include ventilation and space conditioning, temperature and humidity control, acoustics, occupant perception, worker productivity, and other related factors. An integrated protocol consisting of appropriate engineering measurements and related occupant surveys is developed …

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Flesh And Stone: A Wanderer's Mosaic, Tamaria L Anderson Jan 2005

Flesh And Stone: A Wanderer's Mosaic, Tamaria L Anderson

UNLV Retrospective Theses & Dissertations

There are places in the world that never seem to leave the news, and yet for all we hear of them, we really know very little. The West Bank is one of these, its truths and realities obscured by the blinding flash of news cameras and political manipulation. It remains near the front of our consciousness in part because of its constant unrest, but also due to its role as nexus for three main world religions; This work grew out of an impulse to describe and explain the experience of living as a foreigner on the West Bank. Taking the …

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Performance Analysis Of Error Detection And Correction Code For Wireless Sensor Networks, Gopinath Balakrishnan Jan 2005

Performance Analysis Of Error Detection And Correction Code For Wireless Sensor Networks, Gopinath Balakrishnan

UNLV Retrospective Theses & Dissertations

Recent advances in wireless communications and electronics have enabled the development of low-cost, low-power, self-organizational, multifunctional wireless sensor networks. Wireless sensor networks can be applied to a wide range of application areas including heath, military and homeland security, environment, industry and commercial, and home. A typical wireless sensor network consists of one or more sink nodes and a large number of sensor nodes scattered in a sensor field. Each of these sensor nodes is capable to collect the data and relay the data back to the sink through a multi-hop architecture. The key challenge in sensor networks is to overcome …

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Residual Stress Characterization And Defects Analyses By Microscopy, Subhra Bandyopadhyay Jan 2005

Residual Stress Characterization And Defects Analyses By Microscopy, Subhra Bandyopadhyay

UNLV Retrospective Theses & Dissertations

The structural material to contain the spallation target during transmutation of spent nuclear fuel (SNF) may develop internal stresses resulting from forming operations including plastic deformation and welDing Techniques such as pair-production, activation and life-time analysis based on classical positron annihilation spectroscopy (PAS) have been used to characterize residual stresses in candidate structural materials subjected to cold-reduction, plastic deformation and welDing Since the PAS techniques can only provide qualitative evaluation of residual stress, calibration curves were developed to estimate the resultant residual stress as a function of PAS line-shape parameters. Since plastic deformation can lead to the generation of defects …

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Youth Culture, Clothing, And Communicative Messages, Eric Batson Jan 2005

Youth Culture, Clothing, And Communicative Messages, Eric Batson

UNLV Retrospective Theses & Dissertations

As a nonverbal form of communication, clothing reveals much about its wearers. In addition to exposing attitudes, values, beliefs, and other personal traits, individuals can utilize clothing to disseminate deliberate, symbolic messages. This project focuses on youth subcultures and the messages associated with their strategically constructed clothing images. It addresses how they display in-group affiliation and out-group separation through the management of clothing. It discusses how individuals can increase their personal value with in-group members as they manage their apparel in appropriate and deliberate ways. This thesis also notes the multiple influences that affect the clothing choices of youth subcultures …

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Interactive Message Debugger For Parallel Message Passing Programs Using Lam-Mpi, Hoimonti Basu Jan 2005

Interactive Message Debugger For Parallel Message Passing Programs Using Lam-Mpi, Hoimonti Basu

UNLV Retrospective Theses & Dissertations

Many complex and computation intensive problems can be solved efficiently using parallel programs on a network of processors. One of the most widely used software platforms for such cluster computing is LAM-MPI. To aid develop robust parallel programs using LAM-MPI we need efficient debugging tools. The challenges in debugging parallel programs are unique and different from those of sequential programs. Unfortunately available parallel debuggers do not address these challenges adequately; This thesis introduces IDLI, a parallel message debugger for LAM-MPI, designed on the concepts of multi-level debugging. IDLI provides a new paradigm for distributed debugging while avoiding many of the …

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