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Distributed Model Predictive Control Of Power Converters In Microsrids Under Different Modes Of Operation, Riyadh Toman Thahab Toman

Dissertations

Microgrids consist of many distributed energy sources (DERs) and the overall system is viewed as a number of subsystems. In this work, a finite control set model predictive control is proposed to control power converters in both grid and island modes of operation of the microgrid. Each subsystem is assigned a local controller that relies on measurements of common coupling point (PCC) and/or terminal quantities to provide accurate regulation of current or voltage components. This meets the local objective of each subsystem and contributes to the global objective of the microgrid.

In the first part of the work, a microgrid …

Reverse Migration: Documenting How The Educational Experiences Of Transnational Youth In Mexican Schools Are Shaped By Parental Deportation, Sandra Lourdes Candel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Research Problem

Over 500,000 U.S.-born children are living in Mexico –some due to parental deportation– experiencing a decrease in their quality of life, the stress of an unfamiliar language and culture, and difficulty accessing education. In order to support them in their transition to Mexico, and to reincorporate them into U.S. society as adults, their struggles and educational trajectories should be of great concern to the Mexican and U.S. governments, as well as higher education institutions.

Purpose

The purpose of this qualitative study was to document the educational experiences of transnational students attending schools in a border city in northern …

Exterior Giant Planet Effects On Terrestrial Architecture, Anna Corinne Childs

UNLV Theses, Dissertations, Professional Papers, and Capstones

Terrestrial planet formation is a chaotic and violent process which is not fully understood. Prior to Kepler, Solar System observations were the basis for planet formation models. How- ever, Kepler observations have shown that exoplanet systems are very different from our solar system, thus requiring a more complete planet formation model. With advancements in com- putational ability, N-body integrators, and collision models, we can explore planet formation by experimenting with simulations in different parameter space. Our Solar System has shown us that exterior giant planets can play a vital role in the shaping of the final terrestrial planet system. Our …

Understanding The Long-Term Changes In Hydrologic Processes On A Watershed Scale Due To Climate Variability And Change, Chao Chen

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the past century, the population explosion and economic development have resulted in global warming, which has raised a series of concerns, such as sea-level rise, food security, and water resources management. The water flow patterns and features experience both short-term and long-term changes in responses to the changes in the hydrologic processes and meteorologic conditions. On a watershed scale, it is crucial to understand, quantify, and attribute the influences of climate change on the local water resources system. Such understanding can be of great help to undertake local water management tasks, such as flood control, reservoir operation, ecosystem services, …

A Historical Case Study Of Title Ix In Nevada: An Excellent Investment In Our Youth, Jason Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to examine and document the history of Title IX in the American West, specifically at the University of Nevada, Reno (UNR), and at Clark County School District (CCSD) in Las Vegas, Nevada. This thesis contends that since the late nineteenth-century, women have utilized sports as a method to shed discriminatory stereotypes, fight for inclusion, and promote gender equality. In addition, the progressive actions of educational administrators and community leaders regarding Title IX make both UNR and CCSD exceptional institutions for gender equality. This thesis contains six chapters including the introduction and conclusion. Chapter 1 …

Worked To Leisure: The Intersections Of Volunteerism, Work, And Leisure, Denise Nicole Cook

UNLV Theses, Dissertations, Professional Papers, and Capstones

Volunteerism and work are topics which academics in several disciplines research. This study is an examination of the intersection of work and volunteerism via the lens of role theory. According to role theorists, the term role refers to behaviors which are either a result of social position or expectations (Biddle 1986). Cognitive role theorists use vocabulary such as “role conflict” and “role overload” to identify incongruences sometimes found in roles individuals have in their lives (Biddle 1986). These incongruences are primarily examined as they relate to individual level consequences. This research explores volunteerism and work as they relate to role …

Sex Worker And Proud: A Phenomenological Study Of Consensual Sex Workers' Lives, Michael Gerald Curtis Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ten consensual sex workers who were currently working in Nevada were qualitatively interviewed in an effort to explore their perceptions of the adult industry. Interviews specifically focused on their experience disclosing their profession to others and the potential effects that it has on their personal relationships, and access to effective treatment. The Moustakas method of phenomenological inquiry was used to analyze data from ten participants who self-identified as direct sex workers. Seven essential themes emerged from this analysis: (1) the adult industry provides professional and personal agency, (2) the industry is often transient, (3) disclosure is an impactful and ongoing …

Radiative Contour Mapping Using Uas Swarm, Zachary Cook

UNLV Theses, Dissertations, Professional Papers, and Capstones

The work is related to the simulation and design of small and medium scale unmanned aerial system (UAS), and its implementation for radiation measurement and contour mapping with onboard radiation sensors. The compact high-resolution CZT sensors were integrated to UAS platforms as the plug-and-play components using Robot Operation System. The onboard data analysis provides time and position-stamped intensities of gamma-ray peaks for each sensor that are used as the input data for the swarm flight control algorithm. In this work, a UAS swarm is implemented for radiation measurement and contour mapping. The swarm of UAS has advantages over a single …

The Role Of Pre-Existing Type 2 Diabetes Mellitus In Colorectal Cancer Stage And Survival In Elderly Americans: A Seer-Medicare Population-Based Study 2002-~2011, Sanae El Ibrahimi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Diabetes is a common comorbid condition among colorectal cancer (CRC) patients, yet its effects in CRC outcomes, particularly stage at diagnosis, risk of death and variations by diabetes severity (complications vs no complications) and Hispanic ethnicity have not been adequately studied. The purpose of this study was to investigate the association between pre-existing T2DM and advanced stage at diagnosis in elderly patients with CRC; to examine whether diabetes is an independent predictor of poor survival from all-cause and CRC-specific mortality; to assess whether variations exist by diabetes severity and to analyze the outcomes for the Hispanic group.

The Surveillance Epidemiology …

A Test Driven Approach To Develop Web-Based Machine Learning Applications, Armin Esmaeilzadeh

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this thesis is to propose the design and architecture of a testable, scalable, and ef-cient web-based application that models and implements machine learning applications in cancer prediction. There are various components that form the architecture of our web-based application including server, database, programming language, web framework, and front-end design. There are also other factors associated with our application such as testability, scalability, performance, and design pattern. Our main focus in this thesis is on the testability of the system while consid- ering the importance of other factors as well.

The data set for our application is a …

Synthesis Of Actinide Materials For The Study Of Basic Actinide Science And Rapid Separation Of Fission Products, Jacquelyn M. Dorhout

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation covers several distinct projects relating to the fields of nuclear forensics and basic actinide science. Post-detonation nuclear forensics, in particular, the study of fission products resulting from a nuclear device to determine device attributes and information, often depends on the comparison of fission products to a library of known ratios. The expansion of this library is imperative as technology advances. Rapid separation of fission products from a target material, without the need to dissolve the target, is an important technique to develop to improve the library and provide a means to develop samples and standards for testing separations. …

Competitive Power Down Methods In Green Computing, James Andro-Vasko

UNLV Theses, Dissertations, Professional Papers, and Capstones

For the power-down problem one considers a device which has states OFF, ON, and a number of intermediate states. The state of the device can be switched at any time. In the OFF state the device consumes zero energy and in the ON state it works at its full power consumption. The intermediate states consume only some fraction of energy proportional to the usage time but switching back to the ON state has has different constant setup cost depending on the current state. Requests for service (i.e. for when the device has to be in the ON state) are not …

Investigation Of Setting Time And Compressive Strength Of Ready-Mixed Concrete Blended With Returned Fresh Concrete, Negasi Niguse Gebremichael

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Center for Sustainable Transportation Infrastructure (CSTI), in its 2012 study, estimated that out of all the concrete leaving the plant, between 2% and 7% of concrete returns to the plant unused as a returned fresh concrete (RFC). Disposal of both the truck wash water and RFC is a growing concern for the industry. Most industry personnel contacted during the investigation, agree that reusing is superior to recycling of this substantial RFC economically and environmentally. This study will determine if the reuse of RFC in subsequent batches compromises the quality of newly blended concrete.

The effect of RFC on fresh …

Complete Sequencing And Comparative Analysis Of The Genomes Of The First Magnetotactic Gammaproteobacteria Isolated In Pure Culture: Strains Bw-2 And Ss-5, Corey Geurink

UNLV Theses, Dissertations, Professional Papers, and Capstones

The genomes of the first two discovered magnetotactic bacteria (MTB) belonging to the ammaproteobacteria, strains BW-2 and SS-51, were sequenced, sealed, annotated and compared to MTB of other phylogenetic groups. Cells of both strains are rod-shaped and biomineralize cuboctahedral and elongated octahedral crystals of magnetite, respectively, that are enveloped in a protein-embedded, lipid-bilayer membrane referred to as the magnetosome membrane or vesicle. The crystals and their associated membranes are known as magnetosomes. Magnetosome crystals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and, because of their specific mineral compositions, crystal morphologies and sizes, the biomineralization processes involved in magnetosome formation …

Numerical Characterization Of The Flow Field And Heat Transfer Inside The Receiver Of A Parabolic Trough Solar Collector Carrying Supercritical Co2, Samad Gharehdaghimollahajloo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The aim of this research is to provide a detailed numerical analysis of flow field and heat transfer inside the heat collecting element of a parabolic trough collector. The parabolic trough collector is used as the boiler in a direct Super Critical Carbon Dioxide (S-CO2) Brayton cycle.

A single collector is modeled and analyzed with different inlet conditions. The working fluid is supercritical since its pressure is increased to above critical pressure in the compressor while its temperature reaches 300 °C after passing through the recuperators and before entering the solar field. For the first time, this research considers both …

The Impact Of Economic Recession On The Health Of Adult Nevadans, Ariana Goertz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recessions are generally considered to cause negative consequences, but recent studies have provided evidence that some health outcomes improve as the economy deteriorates. The relationship between economic downfalls and health is not straightforward; it is important to look at how health has been impacted in one of the areas hit hardest by the recession. Las Vegas, Nevada was previously considered recession-proof, seemingly unaffected by previous economic downturns exhibited by the rest of the country. However, during the Great Recession of 2007-2009, Las Vegas led the country in highest rates of unemployment and foreclosures. This was quite a collapse for a …

Controlled Electrochemical Reduction Of Gold And Palladium Metal Precursors In Polyaniline, Nicole Goodwin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Polyaniline (PANI) has been extensively studied due to its unique electrochemical properties. The conjugated polymer is conductive with high chemical stability below 100°C, mechanical strength, and large surface area. The applications of PANI have included chemical sensing, corrosion inhibition coatings, light emitting diode and as a substrate for metal composite catalysts. Both chemical and electrochemical methods have been developed and utilized in the synthesis of PANI/metal composites. The simultaneous reduction of aniline and metal precursor produces a composite of PANI encapsulated metal, reducing the active surface area available for catalysis. Alternatively, chemical reduction of the metal precursor into preformed PANI …

Validity And Diagnostic Accuracy Of Broad Symptom Measures And Adhd Symptom Ratings For Identifying Individuals With Adhd Combined And Adhd Inattentive, Stacy Jean Graves

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neuropsychological assessments conducted with children with Attention Deficit Hyperactivity Disorder (ADHD) often includes broad measures of behavioral disturbances, as well as specific measures of ADHD symptomatology. However, it is unclear the extent to which these two types of measures share substantial common variance or are useful in improving diagnostic accuracy. In efforts to increase efficiency, the current study examined these matters to provide clinicians with information that might help improve the selection of behavioral ratings for evaluation purposes.

Participants included in this study were evaluated for clinical purposes at a community based private practice. Participants included 253 of these children …

Evaluating The Chemical And Biological Stability Of Finished Waters Blended For Direct Potable Reuse In A Simulated Distribution System, Assumption Grimaldi

UNLV Theses, Dissertations, Professional Papers, and Capstones

This work evaluated the impacts of blending several different high grade recycled waters with conventional source waters for direct potable reuse (DPR) applications. Bench-scale laboratory tests were conducted for recycled water-source water blends from four participating facilities that have either considered adopting DPR or have already implemented DPR as a feasible approach to overcome water scarcity. The chemical and biological stability of the finished waters was investigated after pipe rig incubation to simulate the quality of blended waters that had aged in a potable water distribution system. The effects of blend ratio, reclaimed water treatment, and source water quality were …

Student Expectations And Motivation In Spanish For Heritage Speakers Programs, Sergio A. Guzman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The changing demographics in the United States and the growing need for multilingual individuals originated by globalization, among other reasons, have contributed to the emergence of a new field within the area of Applied Linguistics: The Teaching and Learning of Heritage Languages. Due to historical and geographic causes, Spanish for Heritage Speakers (SHS) is currently the largest and most established of these programs. However, the curricula, like those of most college courses, has been developed from professors’ perspectives, largely ignoring what students want to learn and/or their motives for enrolling in these classes. The lack of student input is especially …

The Design And Validation Of A Rhythm Span Task, Elizabeth Hofschulte Collins

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to design and validate a rhythm span task. Existing rhythm span tasks do not address important elements of rhythm and music such as tempo (speed), length (duration in beats per minute), and complexity (level of syncopation). This rhythm span task includes every combination of these criteria. The rhythmic sequences were presented with a piano sound from computer audio speakers. To align with traditional simple span tasks, the rhythm span task required participants to reproduce the rhythmic sequence. Results from this study showed that length was a significant factor for difficulty. Short rhythms were found …

Client’S Perception Of Therapist’S Way-Of-Being, Derek Holyoak

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research is to investigate how clients’ perception of their therapist’s way of being impacts client engagement during the therapeutic process. By utilizing a common factors perspective, which emphasizes the importance of a strong therapeutic alliance between clients and therapists, the researcher aims to provide empirical evidence supporting the Therapeutic Pyramid Meta-Model. The Meta-Model, which was created by Fife and colleagues (2014), lays the foundation of effective psychotherapy as a therapist’s way-of-being. The meta-model is concurrent with the common factors literature which accounts for almost 30 percent of therapeutic change to therapist-relationship factors. A phenomenological framework, in …

Studies In Words: Laborious Ben Jonson's Lexicon, Steven Hrdlicka

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation examines significant words in Ben Jonson’s poetic lexicon that the poet inherited, borrowed, and shaped from antiquity and through the Middle Ages. Jonson used etymology as a means to rhetorical inventio, a common practice in the Renaissance. Etymology comprehended more than mere word derivation in the Renaissance but also notably included philological study. Ben Jonson’s extensive knowledge of language, history, architecture, the plastic arts, and philosophy is well known, but the extent to which Jonson’s knowledge of these subjects contributed to his understanding and use of poetic language is not. Thus this dissertation seeks to explore the intellectual …

Surface And Interface Characterization Of Solution-Processed Metal Oxides And Pedot:Pss Using Photoelectron Spectroscopy, Lynette M. Kogler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solution-processed materials are appealing for use in printable electronics as a means to lower production costs, but precise control of the process is crucial for achieving the desired properties in the final materials and their interfaces. Electronic interface properties depend on both the involved materials and their fabrication processes, impacting the development and commercialization of these materials. Analyzing the chemical and electronic structure of these materials, particularly at the surfaces and interfaces, is important not only for insuring that the materials have the desired properties, but also for understanding the effects of the fabrication process and how to modify properties …

Comparison Of Simulation Methods Of Single And Multi-Bit Continuous Time Sigma Delta Modulators, Benju Koirala

UNLV Theses, Dissertations, Professional Papers, and Capstones

Continuous time Sigma Delta Modulators (CT ΣΔMs) are a type of analog to digital converter (ADC) that are used in mixed signal systems to convert analog signals into digital signals. ADCs typically require antialiasing filter; however antialiasing filters are inherent in CT ΣΔMs, and therefore they require less circuitry and less power than other ADC architectures that require separate antialiasing filters. As a result, CT ΣΔM ADC architectures are preferred in many mixed signal electronic applications.

Because of the mixed signal nature of CT ΣΔMs, they can be difficult to simulate. In this thesis, various methods for simulating single-bit and …

Exercise, Learning And Emotional Health: Interdisciplinary Approaches To Translational Action, Tessa L. Koschel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Exercise positively effects physical, psychological and neurological wellbeing. Though the population at large is becoming increasingly aware of the multi-faceted benefits of exercise, the majority of people fail to meet daily exercise recommendations. Largely, demands of everyday life such as work, school and family take priority over fitness. The issue therefore becomes a matter of time. In a world of media multi-tasking and immediate gratification, the challenge to health professionals becomes incorporation and manipulation of these consistencies to improve exercise uptake and adherence. Focus must shift from the idea of making additional time for exercise, to adding exercise to time …

An Analysis Of The Spatial, Temporal, And Functional Role Of Key Proteins In The Drosophila Melanogaster Salivary Gland During Exocrine Secretion, Kathryn Lantz

UNLV Theses, Dissertations, Professional Papers, and Capstones

For over 60 years, the larval salivary gland of Drosophila melanogaster has been the ultimate model for elucidating how steroid hormones trigger genome-wide changes in gene expression in a specific target tissue. Because of the unusual interphase chromosomes of the salivary gland, the regions of the genome that are being induced by the steroid/receptor complex actually form puffs that are easily visible in compound microscopy. Despite the importance of this system, little has been elucidated over the years regarding how the hormone exposure actually changes the physiological activity of this secretory system. The work presented in this dissertation makes a …

Improving Hyperspectral Subpixel Target Detection Using Hybrid Detection Space, Ruixing Li

UNLV Theses, Dissertations, Professional Papers, and Capstones

A Hyper-Spectral Image (HSI) has high spectral and low spatial resolution. As a result, most targets exist as subpixels, which pose challenges in target detection. Moreover, limitation of target and background samples always hinders the target detection performance. In this thesis, a hybrid method for subpixel target detection of an HSI using minimal prior knowledge is developed. The Matched Filter (MF) and Adaptive Cosine Estimator (ACE) are two popular algorithms in HSI target detection. They have different advantages in differentiating target from background. In the proposed method, the scores of MF and ACE algorithms are used to construct a hybrid …

Effects Of Contract Procurement Factors On Performance Of Transportation Projects, Ruiko Maharjan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cost and schedule savings are the main measures of a project’s success. Several factors affect the cost and schedule performances in a construction project, such as design changes, material, labor and equipment shortages, unpredictable weather conditions, and errors & omissions in contract documents.Some studies have shown that either the construction cost or the schedule performance of a project was dependent on the procurement factors, namely: bid cost, number of bidders, the bid cost deviation between the first and second bidder, the liquidated damage rate per day, the type of a contract, and the project location. However, a comprehensive study on …

The Electrochemical Deposition Of Samarium And Europium Dissolved In Ionic Liquid Solvent, Bea Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rare-earth elements include the lanthanide series in the periodic table with the addition of scandium and yttrium. China produces approximately 95% of the world’s rare-earths supply and is the largest consumer of the world’s rare earth supply. Domestic production of rare-earth metals is a priority in the US. The domestic demand for rare-earth elements is largely based on their use in electronic devices, catalytic converters, and more importantly defense applications. Therefore, China’s monopoly of rare-earth elements is viewed as a threat to national security. Although capital investments have resulted in an increase in domestic mining and refining of rare-earth materials, …