Matching Items (476)
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Description
Dynamic loading is the term used for one way of optimally loading a transformer. Dynamic loading means the utility takes into account the thermal time constant of the transformer along with the cooling mode transitions, loading profile and ambient temperature when determining the time-varying loading capability of a transformer. Knowing

Dynamic loading is the term used for one way of optimally loading a transformer. Dynamic loading means the utility takes into account the thermal time constant of the transformer along with the cooling mode transitions, loading profile and ambient temperature when determining the time-varying loading capability of a transformer. Knowing the maximum dynamic loading rating can increase utilization of the transformer while not reducing life-expectancy, delaying the replacement of the transformer. This document presents the progress on the transformer dynamic loading project sponsored by Salt River Project (SRP). A software application which performs dynamic loading for substation distribution transformers with appropriate transformer thermal models is developed in this project. Two kinds of thermal hottest-spot temperature (HST) and top-oil temperature (TOT) models that will be used in the application--the ASU HST/TOT models and the ANSI models--are presented. Brief validations of the ASU models are presented, showing that the ASU models are accurate in simulating the thermal processes of the transformers. For this production grade application, both the ANSI and the ASU models are built and tested to select the most appropriate models to be used in the dynamic loading calculations. An existing application to build and select the TOT model was used as a starting point for the enhancements developed in this work. These enhancements include:  Adding the ability to develop HST models to the existing application,  Adding metrics to evaluate the models accuracy and selecting which model will be used in dynamic loading calculation  Adding the capability to perform dynamic loading calculations,  Production of a maximum dynamic load profile that the transformer can tolerate without acceleration of the insulation aging,  Provide suitable output (plots and text) for the results of the dynamic loading calculation. Other challenges discussed include: modification to the input data format, data-quality control, cooling mode estimation. Efforts to overcome these challenges are discussed in this work.
ContributorsLiu, Yi (Author) / Tylavksy, Daniel J (Thesis advisor) / Karady, George G. (Committee member) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2011
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The development of a Solid State Transformer (SST) that incorporates a DC-DC multiport converter to integrate both photovoltaic (PV) power generation and battery energy storage is presented in this dissertation. The DC-DC stage is based on a quad-active-bridge (QAB) converter which not only provides isolation for the load, but also

The development of a Solid State Transformer (SST) that incorporates a DC-DC multiport converter to integrate both photovoltaic (PV) power generation and battery energy storage is presented in this dissertation. The DC-DC stage is based on a quad-active-bridge (QAB) converter which not only provides isolation for the load, but also for the PV and storage. The AC-DC stage is implemented with a pulse-width-modulated (PWM) single phase rectifier. A unified gyrator-based average model is developed for a general multi-active-bridge (MAB) converter controlled through phase-shift modulation (PSM). Expressions to determine the power rating of the MAB ports are also derived. The developed gyrator-based average model is applied to the QAB converter for faster simulations of the proposed SST during the control design process as well for deriving the state-space representation of the plant. Both linear quadratic regulator (LQR) and single-input-single-output (SISO) types of controllers are designed for the DC-DC stage. A novel technique that complements the SISO controller by taking into account the cross-coupling characteristics of the QAB converter is also presented herein. Cascaded SISO controllers are designed for the AC-DC stage. The QAB demanded power is calculated at the QAB controls and then fed into the rectifier controls in order to minimize the effect of the interaction between the two SST stages. The dynamic performance of the designed control loops based on the proposed control strategies are verified through extensive simulation of the SST average and switching models. The experimental results presented herein show that the transient responses for each control strategy match those from the simulations results thus validating them.
ContributorsFalcones, Sixifo Daniel (Author) / Ayyanar, Raja (Thesis advisor) / Karady, George G. (Committee member) / Tylavsky, Daniel (Committee member) / Tsakalis, Konstantinos (Committee member) / Arizona State University (Publisher)
Created2011
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Advancements in computer vision and machine learning have added a new dimension to remote sensing applications with the aid of imagery analysis techniques. Applications such as autonomous navigation and terrain classification which make use of image classification techniques are challenging problems and research is still being carried out to find

Advancements in computer vision and machine learning have added a new dimension to remote sensing applications with the aid of imagery analysis techniques. Applications such as autonomous navigation and terrain classification which make use of image classification techniques are challenging problems and research is still being carried out to find better solutions. In this thesis, a novel method is proposed which uses image registration techniques to provide better image classification. This method reduces the error rate of classification by performing image registration of the images with the previously obtained images before performing classification. The motivation behind this is the fact that images that are obtained in the same region which need to be classified will not differ significantly in characteristics. Hence, registration will provide an image that matches closer to the previously obtained image, thus providing better classification. To illustrate that the proposed method works, naïve Bayes and iterative closest point (ICP) algorithms are used for the image classification and registration stages respectively. This implementation was tested extensively in simulation using synthetic images and using a real life data set called the Defense Advanced Research Project Agency (DARPA) Learning Applied to Ground Robots (LAGR) dataset. The results show that the ICP algorithm does help in better classification with Naïve Bayes by reducing the error rate by an average of about 10% in the synthetic data and by about 7% on the actual datasets used.
ContributorsMuralidhar, Ashwini (Author) / Saripalli, Srikanth (Thesis advisor) / Papandreou-Suppappola, Antonia (Committee member) / Turaga, Pavan (Committee member) / Arizona State University (Publisher)
Created2011
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Within the pediatric hospitalization experience, fear and anxiety are two emotions commonly felt by children of all ages. Hospitalized children can greatly benefit from interventions designed to help them cope with these emotions throughout their medical experiences. This study draws on each of our clinical experiences as volunteers at Phoenix

Within the pediatric hospitalization experience, fear and anxiety are two emotions commonly felt by children of all ages. Hospitalized children can greatly benefit from interventions designed to help them cope with these emotions throughout their medical experiences. This study draws on each of our clinical experiences as volunteers at Phoenix Children’s Hospital, and uses a qualitative analysis of three semi-structured interviews with currently employed Child Life Specialists to understand and analyze the use of medical play, a form of play intervention with a medical theme or medical equipment. We explore the goals and benefits of medical play for hospitalized pediatric patients, the process of using medical play as an intervention, including the activity design process, the assessments and adjustments made throughout the child’s hospitalization, and the considerations and limitations to implementing medical play activities. Ultimately, we found that the element of fun that defines play can be channeled into medical play activities implemented by skilled Child Life Specialists, who are experts in their field, in clinical settings to promote several different and beneficial goals, including pediatric patient coping.

ContributorsAguiar, Lara (Co-author) / Garciapeña, Danae (Co-author) / Loebenberg, Abby (Thesis director) / Swanson, Jodi (Committee member) / School of Life Sciences (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Waste pickers are the victims of harsh economic and social factors that have hurt many developing countries and billions of people around the world. Due to the rise of industrialization since the 19th century, waste and disposable resources have been discarded around the world to provide more resources, products, and

Waste pickers are the victims of harsh economic and social factors that have hurt many developing countries and billions of people around the world. Due to the rise of industrialization since the 19th century, waste and disposable resources have been discarded around the world to provide more resources, products, and services to wealthy countries. This has put developing countries in a precarious position where people have had very few economic opportunities besides taking on the role of waste pickers, who not only face physical health consequences due to the work they do but also face exclusion from society due to the negative views of waste pickers. Many people view waste pickers as scavengers and people who survive off of doing dirty work, which creates tensions between waste pickers and others in society. This even leads to many countries outlawing waste picking and has led to the brutal treatment of waste pickers throughout the world and has even led to thousands of waste pickers being killed by anti-waste picker groups and law enforcement organizations in many countries. <br/> Waste pickers are often at the bottom of supply-chains as they take resources that have been used and discarded, and provide them to recyclers, waste management organizations, and others who are able to turn these resources into usable materials again. Waste pickers do not have many opportunities to rise above the situation they are in as waste picking has become the only option for many people who need to provide for themselves and their families. They are not compensated very well for the work they do, which also contributes to the situation where waste pickers are forced into a position of severe health risks, backlash from society and governments, not being able to seek better opportunities due to a lack of earning potential, and not being connected with end-users. Now is the time to create new business models that solve these large problems in our global society and create a sustainable way to ensure that waste pickers are treated properly around the world.

ContributorsKidd, Isabella Joy (Co-author) / Kapps, Jack (Co-author) / Urbina-Bernal, Alejandro (Thesis director) / Byrne, Jared (Committee member) / Marseille, Alicia (Committee member) / Jordan, Amanda (Committee member) / Dean, W.P. Carey School of Business (Contributor) / Morrison School of Agribusiness (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Department of Finance (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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This study tested the effect of status threat on ingroup identification and examined identity concealability and stereotype endorsement as moderators of the relationship. Participants included a visible identity group (Asian men) and a concealable identity group (gay men). Participants were randomized into either a status threat condition, in which they

This study tested the effect of status threat on ingroup identification and examined identity concealability and stereotype endorsement as moderators of the relationship. Participants included a visible identity group (Asian men) and a concealable identity group (gay men). Participants were randomized into either a status threat condition, in which they read a vignette that reminded them of a negative stereotype about the target group and discussed positive stereotypes of the group as well, or a control condition that discussed positive stereotypes only. Participants then responded to a measure of ingroup identification and a measure of stereotype endorsement. A significant main effect of status threat on ingroup identification was found, such that participants in the status threat condition showed lower ingroup identification. The interaction of condition and concealability was not significant. The interaction of condition and stereotype endorsement was marginally significant, such that the main effect shows up stronger for those lower on stereotype endorsement. The main effect is interpreted as a potential protective strategy for self-esteem. The stereotype threat interaction is interpreted as a difference in the way that those who do and do not endorse the stereotype view the legitimacy of the status threat.

ContributorsWeathers, Shelby E (Author) / Shiota, Michelle (Thesis director) / Kenrick, Douglas (Committee member) / Wiezel, Adi (Committee member) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Watts College of Public Service & Community Solut (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

When earning a teaching certification, there is no curriculum when it comes to the treatment of students with a diagnosis as well as how to educate their fellow classmates. Diagnoses affect the process of child development of the diagnosed as well as the friends and family. Children of all different

When earning a teaching certification, there is no curriculum when it comes to the treatment of students with a diagnosis as well as how to educate their fellow classmates. Diagnoses affect the process of child development of the diagnosed as well as the friends and family. Children of all different ages have different responses and reactions to the world of health. Looking at a developmental perspective, teachers can properly educate themselves and their students about these diagnoses. To be able to successfully inform students of diagnoses, there must be an overall understanding of how well they are able to acquire the knowledge. According to Jean Piaget, a key researcher in cognitive development, the age of the child correlates with their overall understanding and comprehension. In his theory, he explained how he believed that the environment of an organism affects how it will respond and adapt to the situations at hand. There are four stages that are connected to age, from infancy to adolescence and adulthood. Therefore, this project will focus on school-age children who are in the concrete operational stage. The concrete operational stage is made up of elementary and early adolescents and focuses on intelligence that is demonstrated through logical and precise thinking of concrete ideas (Huitt, W., & Hummel, J, 2003). This type of thinking applies to all parts of the child’s life and informs their behaviors on how to “adapt” to new information. Knowing this information, we will be able to create a curriculum of lectures, informational videos, worksheets and quizzes that can properly assess the student’s and their knowledge of the diagnoses.

ContributorsGreer, Rebecca E. (Author) / Visconti, Kari (Thesis director) / Collins, Jena (Committee member) / Sanford School of Social and Family Dynamics (Contributor) / School of Community Resources and Development (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Soccer is bar none, the most popular sport in the entire world. It is played, followed, and loved by virtually every single country on Earth. Despite this massive support for the sport which houses some of the world’s biggest names in the world, its shortcomings when dealing with issues of

Soccer is bar none, the most popular sport in the entire world. It is played, followed, and loved by virtually every single country on Earth. Despite this massive support for the sport which houses some of the world’s biggest names in the world, its shortcomings when dealing with issues of racial injustice and incidents of racist behavior have become more pronounced in recent years. Although this open discussion regarding racism within the sport has recently begun to sprout, its roots can be tied back to decades ago while continuing to the present day, with players, referees, coaches, fans, commentators, and more all involved on both sides of the issue. <br/> We found this topic to be most prevalent in today’s society after witnessing multiple shameful racist incidents that have occurred to some of the world’s biggest players throughout European football in 2019, as well as the recent ongoing fight for racial reform and increased awareness regarding racial injustice in the United States. By doing comprehensive research and analysis on such incidents that have occurred throughout the years we hope to raise more awareness regarding this subject that has plagued the beautiful game. In addition, we hope to offer ways to remedy the problem one step at a time, all while answering the tough, but necessary questions regarding what specifically should be done in the sport, that others have been afraid to talk about for far too long. Specifically, we wanted to mainly highlight the experience of black players, with a further discussion on other minority groups, in English and Italian football as these two leagues have been a part of the largest debate between how club traditions, player-fan interactions, league policies, and staff management have all affected the way we view the game as the endemic of racism within the sport is exacerbated.

ContributorsPaul, Nikhil (Co-author) / Nazareno, Nathan (Co-author) / Jackson, Victoria (Thesis director) / Harrison, Jennifer (Committee member) / School of Life Sciences (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

Flora Vita is a digital platform that connects families to outdoor excursions, programmed activities and local events, encouraging the familial ecosystem to flourish within Arizona's vast environment. We curate unique opportunities that allow families to cultivate internal relationships with one another and form relationships with local like-minded families in pursuit

Flora Vita is a digital platform that connects families to outdoor excursions, programmed activities and local events, encouraging the familial ecosystem to flourish within Arizona's vast environment. We curate unique opportunities that allow families to cultivate internal relationships with one another and form relationships with local like-minded families in pursuit of a healthy lifestyle.

ContributorsGarcia, Kate (Co-author) / Plunkett, Nina (Co-author) / Byrne, Jared (Thesis director) / Hall, Rick (Committee member) / Silverstein, Taylor (Committee member) / School of Human Evolution & Social Change (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

Graduating from college is an important time of life transitions and career development for undergraduates and their future. Future self-identification, the connection between an individual’s current and future self, can negatively predict depression and utilize self-control as a mechanism to achieve later academic goals. Investigating an individual’s future self- identification,

Graduating from college is an important time of life transitions and career development for undergraduates and their future. Future self-identification, the connection between an individual’s current and future self, can negatively predict depression and utilize self-control as a mechanism to achieve later academic goals. Investigating an individual’s future self- identification, depression scores, and behavioral outcomes in the face of the COVID-19 pandemic can help optimize college graduate success in an uncertain world. The present study aimed to (1) determine if earlier future self-identification moderated the changes between later outcomes (e.g., depression, perceived alcohol consumption, and academic and career goals) from pre-COVID-19 to during COVID-19, (2) investigate if psychological resources (e.g., self-control and emotion regulation) had any intermediary effects between earlier future self-identification and later depression and behavioral outcomes during the pandemic, and (3) test for any moderation effects of future self-identification on the relationship between available psychological resources before COVID-19 and during COVID-19. The present research demonstrated that students with greater earlier future self-identification were less likely to change their academic and career goals and were less likely to experience symptoms of depression during the pandemic. Additionally, self-control was demonstrated as an intermediary factor between earlier future self-identification and later academic and career goal changes. These findings may help college graduates develop resilience in other stressful situations.

ContributorsKadotani, Kamryn Midori (Author) / Kwan, Virginia Sau Y. (Thesis director) / Davis, Mary (Committee member) / McMichael, Samantha (Committee member) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05