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Examining The Cognitive Theory Of Depression Using Descriptive Experience Sampling, Jedidiah D Gunter Jan 2007

Examining The Cognitive Theory Of Depression Using Descriptive Experience Sampling, Jedidiah D Gunter

UNLV Retrospective Theses & Dissertations

The goal of this study was to examine the experience of depressed and nondepressed individuals, exploring the extent to which the specific constructs identified in Beck's cognitive theory of depression were differentially reflected in the momentary experiences of depressed individuals. This involved recruiting depressed and nondepressed individuals and then assessing their inner experience using both the traditional questionnaire measures developed in accord with Beck's theory and Descriptive Experience Sampling. Depressed participants showed substantial variability in the nature of their inner experience, had less frequent inner speech and more feelings than nondepressed participants. Salient characteristics found in the depressed participants' sampled …

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Image Manipulation: Photoshop As A Data-Measurement Tool, Tracilee Rose Hoffman Jan 2007

Image Manipulation: Photoshop As A Data-Measurement Tool, Tracilee Rose Hoffman

UNLV Retrospective Theses & Dissertations

Researchers believe that image manipulation threatens photography's perceived objectivity of capturing moments in history. Current research exists that is aimed at determining whether images have been subjected to methods of manipulation. While this research is thorough in its approaches to detection, it lacks methods that would facilitate the measurement of those manipulations; This study uses Photoshop to measure the qualitative changes in images. The aesthetic dimensions set forth by Gillian Rose (2007) such as content, color, spatial organization, and light can be isolated, manipulated, and ultimately measured; This research is aimed at facilitating additional questions regarding what constitutes image manipulation, …

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Complexation And Electrode Effects On The Electrochemical Behavior Of The Cerium(Iv)/Cerium(Iii) Redox Couple, Sandra Elias Elkouz Jan 2007

Complexation And Electrode Effects On The Electrochemical Behavior Of The Cerium(Iv)/Cerium(Iii) Redox Couple, Sandra Elias Elkouz

UNLV Retrospective Theses & Dissertations

The electrochemistry of the Ce(IV)/Ce(III) redox couple was investigated as a function of working electrode composition and solution environment. Optimum redox couple resolution in aqueous sulfuric acid was achieved at an acid concentration of 0.1 M. A decline in redox couple resolution and reversibility was observed as acid concentration was increased to 2.0 M. The influence of pH was illustrated using sulfate solutions of increasing pH and constant ionic strength. Results indicated that a pH greater than 2 was detrimental to redox couple resolution. The glassy carbon electrode provided the widest potential window and was least affected by changes in …

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On The Coefficients Of Ternary Cyclotomic Polynomials, Thomas Joseph Flanagan Jan 2007

On The Coefficients Of Ternary Cyclotomic Polynomials, Thomas Joseph Flanagan

UNLV Retrospective Theses & Dissertations

In this paper we investigate the coefficients of ternary cyclotomic polynomials. That is, we investigate the coefficients polynomials given by Fnz= 1⩽k⩽n n,k =1 z-e2pik/n , where n is the product of three distinct odd primes (n = pqr); First we show the coefficients of phipqr( z) are loosely connected to the residue of r modulo pq. In particular we show that if r1≡ r2 mod pq and r 1

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Local Leakage Measurement And Cfd Prediction Of K-Factors Of Leaks In Residential Hvac Ducts, Radhika Gundavelli Jan 2007

Local Leakage Measurement And Cfd Prediction Of K-Factors Of Leaks In Residential Hvac Ducts, Radhika Gundavelli

UNLV Retrospective Theses & Dissertations

The experimental work in this research focuses on a new technique, Duct pressurization Local Leakage (DPLT) technique, developed to locate leaks in residential HVAC ducts and to quantify their leak rates. The local leakage rate determined by this technique was compared with known leakage from artificial holes. This technique was also evaluated by comparing the measured total leakages with that determined by standard duct pressurization test and Delta Q. The tests were conducted at the Air Duct Leakage Laboratory (ADLL) which has two air distribution systems and a wide range of leakage rates. The technique produces relatively small scatter and …

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A Method For Estimating Intensity Of A Poisson Process, Sandhya Gunti Jan 2007

A Method For Estimating Intensity Of A Poisson Process, Sandhya Gunti

UNLV Retrospective Theses & Dissertations

Motivated by its vast applications, we investigate ways to estimate the intensity of a Poisson process. Much of the work on modeling and analysis of repairable systems is based on the assumption of a special type of nonhomogeneous Poisson process (NHPP) known as Weibull process or Power-law process. In this thesis, we link the traditional homogeneous and nonhomogeneous Poisson processes to the classical time series via a sequence of the empirical recurrence rates (ERR), calculated at equally spaced intervals of time. We consider a computationally simple algorithm to calculate the total area and also the area for the last ten …

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Hotel Satisfaction And Booking Channels: The Bayesian Rule And Regression Analysis, Tatiana Poliakova Jan 2007

Hotel Satisfaction And Booking Channels: The Bayesian Rule And Regression Analysis, Tatiana Poliakova

UNLV Retrospective Theses & Dissertations

The study utilizes the Bayesian mechanism and calculates the likelihood for each of the booking channels in the study to supply to lodging operations UNLV students who will become highly satisfied with the subsequent hotel stays. Hospitality proprietary booking channels (booking by phone or booking through a hotel's own web site) are more likely to supply a highly satisfied student traveler to an operation than intermediary booking channels, such as booking through a merchant site or addressing a travel agent; Moreover, UNLV students who utilize hospitality proprietary channels tend to bring higher room revenue to a lodging operation than the …

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Determination Of Transformation Function For Predictor Variables In Multiple Linear Regression, Vimatha Ravi Jan 2007

Determination Of Transformation Function For Predictor Variables In Multiple Linear Regression, Vimatha Ravi

UNLV Retrospective Theses & Dissertations

In multiple linear regression involving several predictor variables, finding a suitable non-linear transformation of the predictors might be helpful to present the model in a simple functional form which is linear in the transformed variables. In this thesis, a computer code in C++ is developed to automate the process of finding a suitable transformation for the predictors. This is done by finding the transformation that yields the maximum correlation between the response and the transformed predictor. Several simulated examples are included to illustrate the method. A prime concern in calculating the correlation between two data sets is statistical accuracy. Correlation …

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Atmospheric Dispersion Model Validation For Low Wind Speed Conditions, Patrick Shawn Sawyer Jan 2007

Atmospheric Dispersion Model Validation For Low Wind Speed Conditions, Patrick Shawn Sawyer

UNLV Retrospective Theses & Dissertations

Atmospheric plume dispersion models are used for a variety of purposes including emergency planning and response to hazardous material releases, determining force protection actions in the event of a WMD attack and for locating sources of pollution. This paper provides a review of previous studies that examine the accuracy of atmospheric plume dispersion models for chemical releases. It considers the principles used to derive air dispersion plume models and looks at three specific models currently in use; ALOHA, EPIcode and SCIPUFF. Results from this study indicate over-prediction bias by the EPIcode and SCIPUFF models and under-prediction bias by the ALOHA …

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Estimating The Effects Of Casino Marketing Activities On Slot Business Volume: A Model For Leisure Services Businesses, Lisa Birtciel Young Jan 2007

Estimating The Effects Of Casino Marketing Activities On Slot Business Volume: A Model For Leisure Services Businesses, Lisa Birtciel Young

UNLV Retrospective Theses & Dissertations

This study researched the effect of marketing promotions on gaming volume (i.e., coin-in). Specifically, this study attempted (1) to gain an understanding of the relationship between specific marketing promotions (slot tournaments, special events, product prize drawings, and no marketing promotions) and gaming volume; and (2) to estimate the magnitude of incremental revenue for each type of promotion. A conceptual model was proposed to examine the effect of the different types of marketing promotions on gaming volume, including two other variables (holidays and day-of-the-week) previously found to influence gaming volume; Secondary data were collected from a Las Vegas Strip property for …

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Evaluating The Benefits Of A Systems Approach To Particulate Matter Air Pollution Management, Stephanie Janene Fincher Jan 2007

Evaluating The Benefits Of A Systems Approach To Particulate Matter Air Pollution Management, Stephanie Janene Fincher

UNLV Retrospective Theses & Dissertations

Although air quality has improved in the United States over the past thirty years, some air quality management areas continue to have serious problems with air pollutants such as particulate matter (NRC 2004). I hypothesize that using a systems approach would have benefits for PM10 management, including improved results and understanding, as well as identification of ineffective policies. A system dynamics model was developed for PM10 in the Las Vegas Valley. Policy analysis revealed real-world behavior, important dynamics of the system, and potentially harmful policies. Results support the importance of a systems and long-term perspective, and show that PM10 pollution …

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Shock Attenuation And Impact Characteristics For Children Running At Different Stride Lengths, Kunal Bhanot Jan 2007

Shock Attenuation And Impact Characteristics For Children Running At Different Stride Lengths, Kunal Bhanot

UNLV Retrospective Theses & Dissertations

The purpose of this study was to quantify shock attenuation (SA) and impact characteristics for children (boys and girls) running with different stride lengths (SL). Ten physically active children (10.7+/-1.1 yrs; 40+10.3 kg; 145.2+/-7.3 cm) ran at a constant speed of 3m/s +/- 5% range to complete three stride length conditions: Preferred stride length (PSL), -15%PSL and +15%PSL. During PSL, participants were given no instructions regarding stride length. During -15%PSL and +15%PSL, participants were required to strike markers placed on the floor that resulted in stride length of -15% and +15% of PSL. Ground reaction forces were recorded (1008 Hz) …

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Document Boundary Determination Using Structural And Lexical Analysis, Marc-Allen Cartright Jan 2007

Document Boundary Determination Using Structural And Lexical Analysis, Marc-Allen Cartright

UNLV Retrospective Theses & Dissertations

A method of sequentially presented document determination using parallel analyses from various facets of structural document understanding and information retrieval is proposed in this thesis. Specifically, the method presented here intends to serve as a trainable system when determining where one document ends and another begins. Content analysis methods include use of the Vector Space Model, as well as targeted analysis of content on the margins of document fragments. Structural analysis for this implementation has been limited to simple and ubiquitous entities, such as software-generated zones, simple format-specific lines, and the appearance of page numbers. Analysis focuses on change in …

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Friendly Index Sets Of Starlike Graphs, Daniel Anthony Corral Jan 2007

Friendly Index Sets Of Starlike Graphs, Daniel Anthony Corral

UNLV Retrospective Theses & Dissertations

For a graph G = (V, E) and a coloring (labeling) f : V(G) → Z2 let vf(i) = | f-1(i)|. The coloring f is said to be friendly if |vf(1) - v f(0)| ≤ 1. The coloring f : V( G) → Z2 induces an edge labeling f* : E( G) → Z2 defined by f* (xy) = f( x) + f(y) (mod 2). Let ef(i) = |f*-1( i)|. The friendly index set of the graph G, denoted by FI (G), is defined by FIG= ef1-ef 0:f isafriendly vertexlabelingof G. In this thesis the friendly index sets of certain …

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A General Mathematical Model Of Stenoses, Jordan Jimmy Crabbe Jan 2007

A General Mathematical Model Of Stenoses, Jordan Jimmy Crabbe

UNLV Retrospective Theses & Dissertations

Incidence and the prevalence rate of stroke in the United States has been of great concern to the Centers for Disease Control and prevention (CDC), National Center for Health Statistics (NCHS), the American Society of Stroke, American Stroke Association and the U.S. government as a whole; Many mathematical models of the stroke problem have been proposed and solved using diverse methods and computations. Most of the models are based on the stenoses, occlusion or rupture of the artery and the formation of cerebral aneurysms, which all lead to the occurrence of stroke; This paper utilizes a direct approach to change …

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Effects Of Music Therapy On Prosocial Behavior Of Students With Autism And Developmental Disabilities, Catherine L De Mers Jan 2007

Effects Of Music Therapy On Prosocial Behavior Of Students With Autism And Developmental Disabilities, Catherine L De Mers

UNLV Retrospective Theses & Dissertations

This research study employed a multiple baseline across participants design to investigate the effects of music therapy intervention on hitting, screaming, and asking of three children with autism and/or developmental disabilities. Behaviors were observed and recorded during 10-minute free-play sessions both during baseline and immediately after music therapy sessions during intervention. Interobserver agreement and procedural fidelity data were collected. Music therapy sessions were modeled on literature pertaining to music therapy with children with autism. In addition, social validity surveys were collected to answer research questions pertaining to the social validity of music therapy as an intervention; Findings indicate that music …

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The Relationship Between Project Characteristics And The Expert Estimation Of Software Development And Maintenance, John Farrish Jan 2007

The Relationship Between Project Characteristics And The Expert Estimation Of Software Development And Maintenance, John Farrish

UNLV Retrospective Theses & Dissertations

Accurately estimating the amount of time and effort required to complete a software development or maintenance project has proven problematic for business. A wealth of literature exists exploring each of the methods for estimating software development, but very little is devoted to understanding how project characteristics relate to estimation accuracy. This research examines expert estimation, the most widely used estimation technique, to determine the relationship between software project characteristics and estimation accuracy. Implications of the findings for research and practice are discussed.

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The Collocation And Meshless Methods For Differential Equations In R(2), Thamira Abid Jarjees Jan 2007

The Collocation And Meshless Methods For Differential Equations In R(2), Thamira Abid Jarjees

UNLV Retrospective Theses & Dissertations

In recent years, meshless methods have become popular ones to solve differential equations. In this thesis, we aim at solving differential equations by using Radial Basis Functions, collocation methods and fundamental solutions (MFS). These methods are meshless, easy to understand, and even easier to implement.

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Behavior Analysis And Characterization Of A Tooling Material At Elevated Temperatures, Julio Malpica Jan 2007

Behavior Analysis And Characterization Of A Tooling Material At Elevated Temperatures, Julio Malpica

UNLV Retrospective Theses & Dissertations

2Phase Technologies, Inc. has developed a reconfigurable tooling system (RTS) to meet the increasing need for quick and inexpensive fabrication of composite parts as well as molding of liquid polymers and cast resins. A change of state tooling material is used in the RTS. The tooling material can be changed from liquid to solid and back to liquid for reutilization. The tooling material consists of hollow silica micro-spheres that flow in a water-silicate based solution. The material can be hardened to a solid by removing the solution with the use of vacuum and by the application of heat. The silica …

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Nonlinear Suboptimal And Adaptive Pectoral Fin Control Of Autonomous Underwater Vehicle, Mugdha S Naik Jan 2007

Nonlinear Suboptimal And Adaptive Pectoral Fin Control Of Autonomous Underwater Vehicle, Mugdha S Naik

UNLV Retrospective Theses & Dissertations

Autonomous underwater vehicles (AUVs) are used for numerous applications in the deep sea, such as hydrographic survey, sea bed mining and oceanographic mapping, etc. Presently, significant amount of effort, is being made in developing biorobotic AUVs (BAUVs) with biologically inspired control surfaces. However, the dynamics of AUVs and BAUVs are highly nonlinear and the hydrodynamic coefficients are not precisely known. As such the development of nonlinear and adaptive control systems is of considerable importance; We consider the suboptimal dive plane control of AUVs using the state-dependent Riccati equation (SDRE) technique. This method provides effective means of designing nonlinear control systems …

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Diffusion Model For Lightning Radiative Transfer Using Spherical Geometry, James Beguah Odei Jan 2007

Diffusion Model For Lightning Radiative Transfer Using Spherical Geometry, James Beguah Odei

UNLV Retrospective Theses & Dissertations

A one-speed Boltzmann transport theory, with diffusion approximations, is applied to study the radiative transfer properties of lightning in optically thick thunder clouds. The cloud is modeled in terms of spherical geometry and studies on the effects of multiple scattering are considered. Mathematically, the cloud is composed of a homogeneous distribution of spherical water droplets. Computationally, the cloud is treated as a nuclear reactor, with photons replaced by neutrons. Diffusion techniques common in nuclear reactor analyses are applied as in [1]. Relevant numerical techniques will be used to simulate the Cloud Results for the obtained intensity distribution will be compared …

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Detecting Microcalcification Clusters In Digital Mammograms: Study For Inclusion Into Computer Aided Diagnostic Prompting System, Gopalkrishna Veni Jan 2007

Detecting Microcalcification Clusters In Digital Mammograms: Study For Inclusion Into Computer Aided Diagnostic Prompting System, Gopalkrishna Veni

UNLV Retrospective Theses & Dissertations

Among signs of breast cancer encountered in digital mammograms radiologists point to microcalcification clusters (MCCs). Their detection is a challenging problem from both medical and image processing point of views. This work presents two concurrent methods for MCC detection, and studies their possible inclusion to a computer aided diagnostic prompting system. One considers Wavelet Domain Hidden Markov Tree (WHMT) for modeling microcalcification edges. The model is used for differentiation between MC and non-MC edges based on the weighted maximum likelihood (WML) values. The classification of objects is carried out using spatial filters. The second method employs SUSAN edge detector in …

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Design And Spectral Analysis Of A Six-Axis Shaker System, Yasoda Krishna Prasad Dhulipalla Jan 2007

Design And Spectral Analysis Of A Six-Axis Shaker System, Yasoda Krishna Prasad Dhulipalla

UNLV Retrospective Theses & Dissertations

Shaker table assemblies can exhibit resonances within their frequency range of operation. The spectral analysis of a six-axis shaker system permits the identification and prediction of resonance frequencies. In the project described here, a small six-axis shaker was tested experimentally. In parallel with the experiments, Finite Element (FE) models of the shaker were generated, and their dynamic performance was simulated. Time data from experimental test series were compared with the responses from FE analysis obtained for identical test conditions. The comparison of the response spectra between experiments and simulation permits the assessment and validation of FE analysis as a predictive …

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Development Of A Flood Forecasting Model For Flamingo Tropicana Watershed In The Las Vegas Valley, Satya Prakash Chataut Jan 2007

Development Of A Flood Forecasting Model For Flamingo Tropicana Watershed In The Las Vegas Valley, Satya Prakash Chataut

UNLV Retrospective Theses & Dissertations

Floods are among the most frequent natural phenomenon that occur due to excessive precipitation. Accurate and current forecasting of floods is necessary to avoid social and economic losses. Forecasting floods in an event of intense rain allows the concerned agencies to adopt appropriate measures such as warnings and evacuations and to initiate corrective and remedial efforts before disaster strikes (Chapman and Canaan, 2001); Las Vegas has experienced rapid population growth since the 1990s. This has brought large-scale increase in impervious land surface due to the expansion of residential, commercial, and industrial area in the valley. The increase in impervious area …

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A Graphical Approach For Verification Of The Central Limit Theorem, Suresh Kumar Veluchamy Jan 2007

A Graphical Approach For Verification Of The Central Limit Theorem, Suresh Kumar Veluchamy

UNLV Retrospective Theses & Dissertations

The distribution of the sample mean, when sampling from a normally distributed population, is known to be normal. When sampling is done from a non-normal population, the above result holds when the number of samples (n) is sufficiently large. This important result is known as the Central Limit Theorem (CLT). The CLT plays a very important role in statistical inference. The logical question that arises is: how large does n have to be before the CLT can be used? No one answer is available in the statistical literature, since n depends on the extent of nonnormality present in the underlying …

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On The Use Of Lognormal Distribution For Environmental Data Analysis, Devarshi Pant Jan 2007

On The Use Of Lognormal Distribution For Environmental Data Analysis, Devarshi Pant

UNLV Retrospective Theses & Dissertations

Contaminant concentration data from Superfund sites is quite often positively skewed, and the log-normal theory based statistical procedures are typically used for such data. Recent work in the environmental statistics literature, however, has shown that the use of log-normal theory based formulas, such as the H-statistic confidence interval, is problematic. The performance of the H -- UCL in the presence of non -- detects in the sample is investigated via simulated examples. When comparing mean contaminant concentration at a site with that of the background, the 2-sample t-test on log-transformed data is commonly used. A part of this thesis deals …

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Evapotranspiration Monitoring Methods Within An Irrigated Mixed Vegetation Environment, Jeremy Robert Dodds Jan 2007

Evapotranspiration Monitoring Methods Within An Irrigated Mixed Vegetation Environment, Jeremy Robert Dodds

UNLV Retrospective Theses & Dissertations

The Colorado River system is one of the most heavily used river systems in the world and as such, accurate water accounting methods are vital. The U.S. Bureau of Reclamation (Reclamation) is charged with accounting for the Colorado River's water use. One tool Reclamation uses to accomplish this is the Lower Colorado River Accounting System (LCRAS). This system uses a combination of remote sensing (RS) and a crop coefficient method to calculate agricultural and phreatophyte evapotranspiration (ET), a crucial component to any water budget. In this study, ET was measured within an irrigated mixed vegetation field (sapling cottonwood and willow, …

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Collaborative Intelligent Email Ranking System, Nathaniel H Whittacre Jan 2007

Collaborative Intelligent Email Ranking System, Nathaniel H Whittacre

UNLV Retrospective Theses & Dissertations

Email has become one of the most powerful communication tools today. It is has widely proliferated in both business and personal use. It allows for fast communication between multiple parties that can be easily understood by even the most novice user, and allows for advanced transfer of data for power users. Even with that, it is one of the most abused systems on the Internet. Email systems have allowed for widespread distribution of the worst viruses on the Internet, causing billions of dollars in damage. Most of the technologies that have been deployed to prevent these types of attacks have …

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Numerical Simulation Of Thermal Comfort And Contaminant Transport In Rooms With Ufad System, Rama Haritha Bandarupalli Jan 2007

Numerical Simulation Of Thermal Comfort And Contaminant Transport In Rooms With Ufad System, Rama Haritha Bandarupalli

UNLV Retrospective Theses & Dissertations

This thesis deals with the numerical simulation of the thermal comfort and contaminant transport of an under floor air distribution (UFAD) system. Within the last few years, UFAD systems have become popular design alternative to conventional distribution (CAD) such as overhead distribution systems for thermal and ventilation control. Recent advances in computational fluid dynamics (CFD) and computer power make it possible to accurately predict some features of airflow within ventilated spaces. The CFD method has been successfully applied for airflow analysis in relatively complicated conditions, such as non-isothermal, three-dimensional and with furniture inside the room. The goal of this research …

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Preservice Teachers' Understanding Of *Evolution, The Nature Of Science, And Situations Of Chance, Louis Scott Nadelson Jan 2007

Preservice Teachers' Understanding Of *Evolution, The Nature Of Science, And Situations Of Chance, Louis Scott Nadelson

UNLV Retrospective Theses & Dissertations

The learning and teaching of biological evolution, the nature of science and situations of chance is conceptually challenging. Attempts to increase understanding in these domains has resulted in limited occurrences of success, and the identification of many related misconceptions. The alternative conceptions have been detected in teachers as well as students, which reflects the complexity of learning the content. Teachers' understanding of these concepts is critical to assuring they do not perpetuate misconceptions by teaching them to their students. The consistent detection of misconceptions in teachers suggests that new approaches to increasing understanding of these concepts need to be explored. …

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