Digital Commons Network^™

Object Detection Using Contrast Enhancement And Dynamic Noise Reduction, Justin Lee Baker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Edge detection is one of the most important steps a computer must perform to gain understanding of an object in a digital image either from disk or from video feed. Edge detection allows for the computer to describe the shape of the objects in an image and create a pixel boundary defining what is considered part of an object, and what is not. Cannys edge detection algorithm is one of the most robust and accurate of these edge detection algorithms. However, as with many algorithms in image processing, there are many cases where the algorithm does not perform as well …

Temperature Trends And Urban Heat Island Intensity Mapping Of The Las Vegas Valley, Adam Leland Black

UNLV Theses, Dissertations, Professional Papers, and Capstones

Modified urban climate regions that are warmer than rural areas at night are referred to as Urban Heat Islands or UHI. Islands of warmer air over a city can be 12 degrees Celsius greater than the surrounding cooler air. The exponential growth in Las Vegas for the last two decades provides an opportunity to detect gradual temperature changes influenced by an increasing presence of urban materials. This thesis compares ground based thermometric observations and satellite based remote sensing temperature observations to identify temperature trends and UHI areas caused by urban development.

Analysis of temperature trends between 2000 and 2010 at …

Examining The Relationships Between Internalizing And Externalizing Problems And Academic Achievement, Lara Elizabeth Conrad

UNLV Theses, Dissertations, Professional Papers, and Capstones

The relationship between internalizing and externalizing problems and academic achievement for children and adolescents has been inconclusive. Particularly the relationship between the Behavior Assessment System for Children, Second Edition (BASC-2) reports of internalizing and externalizing problems and academic performance on the Woodcock-Johnson, Tests of Achievement, Third Edition (WJ-III:ACH). The current study examined the self and parent reports of internalizing and externalizing problems as measured by the BASC-2 and the relationship with academic skills as measured by the WJ-III:ACH. The referral source (private practice or school setting) was evaluated for severity of presenting internalizing and externalizing symptoms. Secondary data analysis was …

Examining Household Identity Through Lithic Technology At The Harris Site, Justin Albert Demaio

UNLV Theses, Dissertations, Professional Papers, and Capstones

Utilitarian technology is often studied by archaeologists to understand what specific functions and activities these items represent in a past population's daily life. However, it is important not to forget that technology manufacture, use, and discard is embedded in a social context. Flintknapping is a skill that requires close instruction and training so that the desired outcome can be achieved. This training requires daily mentoring from other individuals in the community, many times within one's own family. These daily interactions create learning frameworks through which craft knowledge is transmitted. Technological style and domestic processing activities can be used as an …

Snail Algorithm For Task Allocation In Mesh Networks, Bartosz Duszel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Topic of this master's thesis is connected with task allocation algorithms and mesh networks. Author of this work has already graduated from Wroclaw, University of Technology (Poland) where during his studies he created software simulation environment for two different task allocation algorithms for mesh networks:Adaptive ScanandFrame Sliding. Those algorithms were compared by two, main parame- ters: simulation time and average mesh fulfillment (utilization level). All simulations were done in software environment which was developed specially for that research. This application was based on few, different types of objects: task (width, height, processing time), task queue (different number of tasks), task …

Design And Fabrication Of An Infrared Optical Pyrometer Asic As A Diagnostic For Shock Physics Experiments, Jared Gordon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Optical pyrometry is the sensing of thermal radiation emitted from an object using a photoconductive device to convert photons into electrons, and is an important diagnostic tool in shock physics experiments. Data obtained from an optical pyrometer can be used to generate a blackbody curve of the material prior to and after being shocked by a high speed projectile. The sensing element consists of an InGaAs photodiode array, biasing circuitry, and multiple transimpedance amplifiers to boost the weak photocurrent from the noisy dark current into a signal that can eventually be digitized. Once the circuit elements have been defined, more …

Impacts Of Climate Changes On The Spatiotemporal Distribution Of Precipitation In The Western United States, Peng Jiang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Precipitation in the Intermountain West is characterized by its great variability in both spatial and temporal distributions. Moreover, the spatiotemporal distribution of the precipitation is changing due to the climate changes. In this dissertation, three studies are conducted to investigate the multi-scale temporal variability of precipitation, the performance of current climate models on this variability, the influence of large-scale ocean oscillations on heavy precipitation, and the impact of human induced global warming on storm properties.

The first study is to examine the performance of current climate models on the simulation of the multi-scale temporal variability determined from the observed station …

Feasibility Of The Use Of Ultrasound Measurements For Grade Verification Of The Performance Grade Asphalt Binders, Mehdi Khalili

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research investigates the feasibility of application of high frequency immersion ultrasonic measurement (UM) to discriminate different performance grade (PG) asphalt binders. PG asphalt binder is one of the main components of hot mix asphalt used for roadway construction. UT may provide an inexpensive alternative to sophisticated tests currently used for quality control of PG asphalt binders. Nine different PG asphalt binders used were selected for this investigation. Velocity (V) and integrated response (IR) of the ultrasonic wave were measured. The IR is a measure of the ratio of ultrasonic energy transmitted into the material to the ultrasonic energy reflected …

Nonlinear Adaptive Diffusion Models For Image Denoising, Ajay Kumar Mandava

UNLV Theses, Dissertations, Professional Papers, and Capstones

Most of digital image applications demand on high image quality. Unfortunately, images often are degraded by noise during the formation, transmission, and recording processes. Hence, image denoising is an essential processing step preceding visual and automated analyses. Image denoising methods can reduce image contrast, create block or ring artifacts in the process of denoising. In this dissertation, we develop high performance non-linear diffusion based image denoising methods, capable to preserve edges and maintain high visual quality. This is attained by different approaches: First, a nonlinear diffusion is presented with robust M-estimators as diffusivity functions. Secondly, the knowledge of textons derived …

Kindergarteners' Concept Development In Science And Literacy Learning Through Concept-Oriented Reading Instruction (Cori), Char Adelia Moffit

UNLV Theses, Dissertations, Professional Papers, and Capstones

The notion that "real work" is somehow different from authentic and engaging discovery is troublesome. (Passman, 2001, p.196)

This qualitative case study examined science concept and literacy learning along with engagement of the students in a Kindergarten class in which science and literacy instruction was integrated through Concept-Oriented Reading Instruction (CORI). CORI is an instructional framework created to increase reading engagement by teaching reading comprehension strategies along with science concepts (Guthrie, et al., 1996). This study explored CORI at the Kindergarten level to examine how this curriculum framework engaged young learners in science concept and literacy learning. The study was …

A Case Study Of Zero Energy Home Built For Solar Decathlon Competition 2013, Sanjib Mulepati

UNLV Theses, Dissertations, Professional Papers, and Capstones

Energy consumption in residential homes has been a subject of research related to sustainability. Reduction in the consumption of energy is a goal of sustainable construction. The Department of Energy (DOE) started a Solar Decathlon competition in 2002 in which the students from different universities around the globe build an energy efficient and affordable home suitable for their climate and location. The main goal of this competition is to select the best home that is designed and built in a sustainable way. In this study, the home designed and constructed for participation in the competition by the students at University …

Estimation Of Travel Time Based On Vehicle-Tracking Models, Anuj Nayyar

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis we study the travel time problem based on the known traffic density model. Using the conservation law, we model the travel time function by a boundary value problem of a non homogeneous linear hyperbolic equation. The equation is transformed into an initial value hyperbolic equation, and the well-posedness of the problem is discussed. The mathematical analysis for both density and travel problems are given. We also derive the analytic solutions for several special cases of traffic density. Numerical schemes are proposed for solving for travel time problem. Several numerical examples are presented and error analysis on the …

The Water Wall: A Passive Solar Collection And Thermal Storage Device For Supplementary Radiant Heating, Rhett Roman Noseck

UNLV Theses, Dissertations, Professional Papers, and Capstones

Through the implementation of passive solar building systems, suburbia could take a fresh new step forward toward a progressively more sustainable direction. Making passive solar strategies a priority, master planned community developments would see opportunity to change the style and design of future suburban residences.

The focus and intention of this body of work is to research, design, fabricate, and test a prototype of a passive solar heating device using water as the medium for thermal storage. The size and shape of the design for the water wall device will be determined by the currently built suburban environment; however, for …

Factors Associated With Parental Decision Making And Childhood Vaccination, Zuwen Qiu-Shultz

UNLV Theses, Dissertations, Professional Papers, and Capstones

In order to better understand factors affecting immunization status, logistic regression was used to assess the association of various socio-demographic factors and whether parents would have their child immunized if not a state mandate. Factors included in the study were race, household income, number of children in the household, number of adults in the household, if the child had a primary provider, if the child had a health check-up in the last twelve months, and medical insurance status of the child. The combined Nevada Kindergarten Health Survey Result of 2009-2010 (Year Two) and 2010-2011 (Year Three) conducted by the Nevada …

A Survey On Detection And Defense Of Application Layer Ddos Attacks, Naga Shalini Vadlamani

UNLV Theses, Dissertations, Professional Papers, and Capstones

As the time is passing on, the effect of DDoS attacks on Internet security is growing tremendously. Within a very little span there is a huge increase in the size and frequency of DDoS attacks. With the new technologies and new techniques, the attackers are finding more sophisticated ways to attack the servers. In this situation, it is necessary to come up with various mechanisms to detect and defend these DDoS attacks and protect the servers from the attackers. Many researches have been carried out to detect the DDoS attack traffic in transport layer, which is more vulnerable to DDoS …

Time-Dependent Random Effect Poisson Random Field Model For Polymorphism Within And Between Two Related Species, Shilei Zhou

UNLV Theses, Dissertations, Professional Papers, and Capstones

Molecular evolution is partially driven by mutation, selection, random genetic drift, or combination of the three factors. To quantify the magnitude of these genetic forces, a previously developed time-dependent fixed effect Poisson random field model provides powerful likelihood and Bayesian estimates of mutation rate, selection coefficient, and species divergence time. The assumption of the fixed effect model that selection intensity is constant within a genetic locus but varies across genes is obviously biologically unrealistic, but it serves the original purpose of making statistical inference about selection and divergence between two related species they are individually at mutation-selection-drift inequilibrium. By relaxing …

Ichnology And Paleoecology Of The Jurassic Aztec Sandstone, Heather Marie Stoller

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study I describe and interpret tracks and trackways of the Jurassic Aztec Sandstone of southern Nevada and southern California. This study involved mapping of all known tracks and trackways, including foot length, stride length, and trackway width. Photogrammetric data, collected by Bureau of Land Management scientists, were utilized for several trackways in Red Rock Canyon National Conservation Area.

More than three hundred tracks belonging to five ichnotaxa were documented within the Aztec Sandstone, including about 165 tridactylGrallator, 250 tetradactyl (four-toed)Brasilichniumtracks, and 7 arthropod trackways ofOctopodichnusandPaleohelcura. Four of the five ichnotaxa were not previously reported from the Aztec Sandstone. …

Hearing-Aid Safety: A Comparison Of Estimated Threshold Shifts For Gains Recommended By Nal-Nl2 And Dsl M[I/O] Prescriptions For Children, Teresa Y. C. Ching, Earl E. Johnson, Mark Seeto, John H. Macrae

ETSU Faculty Works

Objective: To investigate the predicted threshold shift associated with the use of nonlinear hearing aids fitted to the NAL-NL2 or the DSL m[i/o] prescription for children with the same audiograms. For medium and high input levels, we asked: (1) How does predicted asymptotic threshold shifts (ATS) differ according to the choice of prescription? (2) How does predicted ATS vary with hearing level for gains prescribed by the two prescriptions? Design: A mathematical model consisting of the modified power law combined with equations for predicting temporary threshold shift (Macrae, 1994b) was used to predict ATS. Study sample: Predicted threshold shift were …

Local Influence In Bayesian Elliptically Contoured-Ordinal Model For Mixed Data, Ehsan B. Samani

Applications and Applied Mathematics: An International Journal (AAM)

This paper develops a new class of joint modeling of mixed correlated ordinal and continuous responses with elliptically contoured errors. This joint model includes the latent variable approach of using an elliptically contoured distribution for mixed ordinal and continuous responses. A Markov Chain Monte Carlo sampling algorithm is described for estimating the posterior distribution of the parameters. For sensitivity analysis to investigate the perturbation from associate responses, it is demonstrated how one can use some elements of covariance structure. Influence of small perturbation of these elements on the posterior normal curvature is also studied. To illustrate the application of such …

The Underlying Physiology Of Arterial Pulse Wave Morphology In Spatial Domain, Nzerem F. Egenti, Alozie H. Nkechi

Applications and Applied Mathematics: An International Journal (AAM)

Cardio-vascular events are among the world’s leading causes of morbidity and mortality. Most postulates suppose that culinary delights can be implicated in incidences of cardio-vascular diseases. This school of thought holds well in many respects. Much as the truistic value of the said school is acknowledged, we conceived of physiological disposition as an endogenous dominant factor in the events being considered, whereas culinary measures constitute an exogenous contributory factor. In this work we aimed at studying the effects of distance (stature) on pulse waveforms. Certain elements of our study showed that pulse wavelength was dominant in prescribing cardio-vascular physiology.

Reducibility Of Eulerian Graphs And Digraphs, Akram B. Attar

Applications and Applied Mathematics: An International Journal (AAM)

In this paper the concept of reducibility in graph theory is discussed, and the deletable vertex (edge) in graph (digraph) is defined. The class of graphs (digraphs) ℛ is called vertex (edge) reducible if for any G∈ ℛ either ℛ is the trivial graph (null graph) or it contains a vertex (edge) v such that G-v∈ ℛ. We introduce some classes of graphs (digraphs) which are reducible and others which are not. The vertex reducibility and edge reducibility of Eulerian graphs and Eulerian digraphs have also been studied.

Some Geometric Properties Of A New Type Metric Space, Muhammed Çınar, Murat Karakaş, Mikail Et

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we define a metric on our new space and then show that this linear metric space is k-nearly uniform convex and has property beta where p = p_k is a bounded sequence of positive real numbers. Finally, we give a result about property (H) by using k-nearly uniform convexity.

Graphic Illustration Of The Transmission Resonances For The Dkp Particles, B. Boutabia-Chéraitia, Abdenacer Makhlouf

Applications and Applied Mathematics: An International Journal (AAM)

We consider the Duffin-Kemmer-Petiau (DKP) equation in the presence of a spatially one-dimensional Woods-Saxon (WS) potential and we show by graphics how the zero-reflection condition on the Klein interval depends on the shape of the potential.

Application Of The Optimal Homotopy Asymptotic Method For Solving The Cauchy Reaction-Diffusion Problem, H. Jafari, S. Gharbavy

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, the optimal homotopy asymptotic method is applied on the Cauchy reaction-diffusion problems to check the effectiveness and performance of the method. The obtained solutions show that the OHAM is more effective, simpler and easier than other methods. Moreover, this technique does not require any discretization or linearization and therefore it reduces significantly the numerical computations. The results reveal that the method is explicit.

Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen

Theses and Dissertations

Important aspects of adhesion occur at interfaces, including structures that may be different from those in the bulk materials. However, probing the orientation of molecules in functional adhesives poses a significant challenge because adhesive molecules are always located at a buried interface. The limited penetration depth of surface-specific analysis prohibits the study of buried interfaces using those techniques. The large quantity of bulk molecules relative to the adhesive molecules interacting at the interface results in the bulk signal swamping out adhesive signal in bulk analysis techniques. An interface-specific technique is required to study functional adhesives. One such technique that has …

Early Interventions And Student Achievement, Alana S. Hillman

Dissertations

Educating children is a costly endeavor; however, when children with special needs enter kindergarten unprepared emotionally, socially, or academically, the increased costs and support systems have to be absorbed by the schools and communities. The purpose of this study was to determine if there was a significant difference between the academic achievement of students participating in Early Childhood Special Education (ECSE) compared to students without ECSE services with DIAL-3 scores ranked in the 20th percentile or below. Achievement scores for second and third graders in one urban school district were utilized to compare the scores of ECSE and non-ECSE students. …

Teachers' Perceptions About The Types, Quality, And Impact Of Their Job-Embedded Professional Development Experiences, Delilah Mitchell

Dissertations

This study was designed to determine eighth grade teachers’ perceptions of the impact, quality, and types of job-embedded professional development activities they have participated in and the relationship to student achievement in language arts, math, or science. The researcher identified school districts with 50% or more of their eighth grade students scoring proficient or advanced on all three areas of Mississippi’s Curriculum Test, Second Edition (MCT2). Sixty-four eighth grade language arts, math, or science teachers who had been at their current school at least two years completed a questionnaire created by the researcher. Multiple Linear Regression and Pearson’s Correlation were …

Second-Order Perturbation Analysis Of The St. Venant Equations In Relation To Bed-Load Transport And Equilibrium Scour Hole Development, Frans Joseph Lambrechtsen

Theses and Dissertations

This analysis is an expansion of research done by Rollin Hotchkiss during his Ph.D work. The research uses fluid flow, sediment transport, and perturbation theory to predict where scour will occur in a variable-width channel. The resulting equations also determine equilibrium scour depth based upon the stream bed elevation derived from a dimensionless bed slope equation. Hotchkiss perturbed the width of the channel using a second order Taylor Series perturbation but neglected second order terms. The present work follows the same procedures as Hotchkiss but maintains the second order terms. The primary purpose is to examine how the additional terms …

Water Fat Separation With Multiple-Acquisition Balanced Steady-State Free Precession Mri, Michael A. Mendoza

Theses and Dissertations

Magnetic resonance imaging (MRI) is an important medical imaging technique for visualizing soft tissue structures in the body. It has the advantages of being noninvasive and, unlike x-ray, does not rely on ionizing radiation for imaging. In traditional hydrogen-based MRI, the strongest measured signals are generated from the hydrogen nuclei contained in water and fat molecules.Reliable and uniform water fat separation can be used to improve medical diagnosis. In many applications the water component is the primary signal of interest, while the fat component represents a signal which can obscure the underlying pathology or other features of interest. In other …

Comparing Full Day Kindergarten To Half Day Kindergarten, Alisha Catherine Bazzano

Dissertations, Masters Theses, Capstones, and Culminating Projects

This study examines half- and full-day kindergarten programs and their effectiveness in regard to a child’s academic progress. Some literature finds a positive relationship between the success of a child and the minutes spent in the classroom. However, other literature debates as to how long the progress is sustained. The purpose of this study is to compare the scores of kindergarten students in both half-day and full-day programs and analyze the data to determine if one program is more successful than the other. Three assessments in language arts were given to each student, assessing uppercase, lowercase, and letter sounds. The …