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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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Description
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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Description
Radiation-induced gain degradation in bipolar devices is considered to be the primary threat to linear bipolar circuits operating in the space environment. The damage is primarily caused by charged particles trapped in the Earth's magnetosphere, the solar wind, and cosmic rays. This constant radiation exposure leads to early end-of-life expectancies

Radiation-induced gain degradation in bipolar devices is considered to be the primary threat to linear bipolar circuits operating in the space environment. The damage is primarily caused by charged particles trapped in the Earth's magnetosphere, the solar wind, and cosmic rays. This constant radiation exposure leads to early end-of-life expectancies for many electronic parts. Exposure to ionizing radiation increases the density of oxide and interfacial defects in bipolar oxides leading to an increase in base current in bipolar junction transistors. Radiation-induced excess base current is the primary cause of current gain degradation. Analysis of base current response can enable the measurement of defects generated by radiation exposure. In addition to radiation, the space environment is also characterized by extreme temperature fluctuations. Temperature, like radiation, also has a very strong impact on base current. Thus, a technique for separating the effects of radiation from thermal effects is necessary in order to accurately measure radiation-induced damage in space. This thesis focuses on the extraction of radiation damage in lateral PNP bipolar junction transistors and the space environment. It also describes the measurement techniques used and provides a quantitative analysis methodology for separating radiation and thermal effects on the bipolar base current.
ContributorsCampola, Michael J (Author) / Barnaby, Hugh J (Thesis advisor) / Holbert, Keith E. (Committee member) / Vasileska, Dragica (Committee member) / Arizona State University (Publisher)
Created2011
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Description

Partisan politics has created an increasingly polarized political climate in the United States. Despite the divisive political climate, women’s representation in politics has also increased drastically over the years. I began this project to see if there is a partisan rivalry between women in politics or a sense of shared

Partisan politics has created an increasingly polarized political climate in the United States. Despite the divisive political climate, women’s representation in politics has also increased drastically over the years. I began this project to see if there is a partisan rivalry between women in politics or a sense of shared “womanhood.” This thesis explores the role political parties play for women in office by examining how they vote on bills, what type of bills they propose, and whether or not they work collaboratively with their female counterparts at the Arizona State Legislature. My main goals for this project are to see how strong or weak political parties are in shaping political behavior at the Arizona State Legislature and to determine if there is a sense of “womanhood” despite different political affiliations. I also explore the role party affiliation plays within women legislators at the Arizona State Legislature.

ContributorsSanson, Claudia Maria (Author) / Lennon, Tara (Thesis director) / Woodall, Gina (Committee member) / School of Public Affairs (Contributor) / Department of English (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Coverage of Black soccer players by Italian media outlets perpetuate narratives rooted in anti-Black racism. These narratives reflect the country’s changing attitude toward immigration. Historically a country from which citizens emigrated, it is now a recipient of immigrants from Africa. These changing demographics have also caused a shift in the

Coverage of Black soccer players by Italian media outlets perpetuate narratives rooted in anti-Black racism. These narratives reflect the country’s changing attitude toward immigration. Historically a country from which citizens emigrated, it is now a recipient of immigrants from Africa. These changing demographics have also caused a shift in the focus of racism in Italy, from discrimination against southern Italians to anti-Black racism. As the country has explored what defines a unified Italian identity, Afro-Italians have been excluded. This study evaluates how these perceptions of Afro-Italian soccer players manifest according to various racial frames, and the frequency with which they do so in three Italian sports dailies: La Gazzetta dello Sport, Corriere dello Sport – Stadio, and Tuttosport. In this context, Afro-Italian refers to an Italian citizen of African descent, and anti-Black racism denotes any form of discrimination, stereotyping, or racism that specifically impacts those of African descent. For this study, a representative sample was collected consisting of website coverage published by the three sports dailies: articles devoted to Mario Balotelli that appeared between 2007 and 2014, and articles devoted to Moise Kean between 2016 and 2019. Three coders recorded the content of the sample articles on a spreadsheet organized by the type of racial frame applied to Black athletes. The analysis reveals that the players were frequently portrayed as being incapable of self-determination and of having an innate, natural athletic capability, rather than one honed through practice. The coders noted that in addition to explicit racial framing, there were also instances of implicit and subtle ways these racial frames manifest. In future research, the coding procedure will need to be adapted to account for these more layered and nuanced manifestations of anti-Black racism.

Created2021-05
Description

The Arizona Teachers Academy is a program that was first designed and implemented by Governor Doug Ducey in 2017 with a simple concept: to cover the tuition and fees of Arizona higher education students learning to teach in exchange for fulfilling a commitment to teach at an Arizona public school

The Arizona Teachers Academy is a program that was first designed and implemented by Governor Doug Ducey in 2017 with a simple concept: to cover the tuition and fees of Arizona higher education students learning to teach in exchange for fulfilling a commitment to teach at an Arizona public school following graduation. The academy has evolved quite rapidly in its short history, going from an unfunded mandate that Arizona universities could not afford to be funded to a voter-approved tax, and seeing its student enrollment numbers increase by over tenfold. This paper seeks to be an overview and process evaluation of the program, as well as an outlook into the program’s future. As a process evaluation, the thesis includes examinations of the program’s presumed logic model, that model’s assumptions, and relevant stakeholders. I used a multi-method approach: statutory and financial data were collected from web research and agency archival collections, and a series of interviews were conducted to ask analytical questions to key stakeholders and program directors about the program’s internal operations and data findings. These stakeholders and program directors consist of staff at the Arizona Board of Regents, the Arizona Department of Education, all three major Arizona public universities (Arizona State University, Northern Arizona University, and the University of Arizona), as well as multiple elected officials and political advocacy groups that have impacted the program through legislation and ballot initiative. This thesis finds that the Arizona Teachers Academy does not have a stated logic model, which in turn led to program assumptions that fail to meet the needs of Arizona public schools and did not allow for all key stakeholders to be involved in the process.

ContributorsLister, Blake (Author) / Lennon, Tara (Thesis director) / Broberg, Gregory (Committee member) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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In the United States, clinical testing is monitored by the federal and state governments, held to standards to ensure the safety and efficacy of these tests, as well as maintaining privacy for patients receiving a test. In order for the ABCTL to lawfully operate in the state of Arizona, it

In the United States, clinical testing is monitored by the federal and state governments, held to standards to ensure the safety and efficacy of these tests, as well as maintaining privacy for patients receiving a test. In order for the ABCTL to lawfully operate in the state of Arizona, it had to meet various legal criteria. These major legal considerations, in no particular order, are: Clinical Laboratory Improvement Amendments compliance; FDA Emergency Use Authorization (EUA); Health Insurance Portability and Accountability Act compliance; state licensure; patient, state, and federal result reporting; and liability. <br/>In this paper, the EUA pathway will be examined and contextualized in relation to the ABCTL. This will include an examination of the FDA regulations and policies that affect the laboratory during its operations, as well as a look at the different authorization pathways for diagnostic tests present during the COVID-19 pandemic.

ContributorsJenkins, Landon James (Co-author) / Espinoza, Hale Anna (Co-author) / Filipek, Marina (Co-author) / Ross, Nathaniel (Co-author) / Salvatierra, Madeline (Co-author) / Compton, Carolyn (Thesis director) / Rigoni, Adam (Committee member) / Stanford, Michael (Committee member) / School of Life Sciences (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Over the course of 2020, individuals and organizations were thrown various unprecedented obstacles that necessitated flexibility, empathy, and understanding. Many organizations were forced to reevaluate their financial status, their purpose, and how they could provide for their employees. The COVID-19 pandemic meant that most companies had to introduce a ‘work

Over the course of 2020, individuals and organizations were thrown various unprecedented obstacles that necessitated flexibility, empathy, and understanding. Many organizations were forced to reevaluate their financial status, their purpose, and how they could provide for their employees. The COVID-19 pandemic meant that most companies had to introduce a ‘work from home’ policy, drastically decreasing the face-to-face contact that employees had with each other and leadership. The virus, coupled with the social and political unrest in the U.S. in the wake of the Black Lives Matter movement and the 2020 presidential election, inspired many companies to reframe their organization and redefine their goals.<br/> The B2B (business-to-business) Marketing Agency, The Mx Group, is preparing for a change in leadership, with the current Chief Executive Officer and Founder stepping down, being replaced by the President of the company. The company plans to execute the transition in the spring of 2022, allowing them the rest of 2021 to plan for the change, catering to employees’ individual and the company’s collective needs. It was also prompted by factors such as the COVID-19 pandemic to reevaluate the values that it upholds as an organization, coinciding with the change in leadership. Leaders of the company are actively encouraging employees to engage with these values by recognizing when a colleague performs in alignment with a value.<br/> In reframing their organization, The Mx Group has a significant opportunity to uniquely position itself in the industry. Lee G. Bolman and Terrence E. Deal (2017) introduced four frames: human resources, symbolic, structural, and political, as a way to guide a transformative application of leadership and management in business. Analyzed from these perspectives, The Mx Group can utilize contemporary ideas to efficiently and effectively seize its opportunity of embedding new values and a change in leadership.

ContributorsLanghorn, Chloe Nicole (Author) / deLusé, Stephanie (Thesis director) / Fishburne, Kate (Committee member) / School of Politics and Global Studies (Contributor) / Department of Management and Entrepreneurship (Contributor) / Department of Finance (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The Constitution is a document that was made over 200 years ago by a population that could have never imagined the type of technology or social advances made in the 21st century. This creates a natural rift between governing ideals between then and now, that needs to be addressed. Rather

The Constitution is a document that was made over 200 years ago by a population that could have never imagined the type of technology or social advances made in the 21st century. This creates a natural rift between governing ideals between then and now, that needs to be addressed. Rather than holding the values of the nation to a time when people were not considered citizens because of the color of their skin, there need to be updates made to the Constitution itself. The need for change and the mechanisms were both established by the Framers while creating and advancing the Constitution. The ideal process to go about these changes is split between the formal Article V amendment process and judicial activism. The amendment process has infinite scope for changes that can be done, but due to the challenge involved in trying to pass any form of the amendment through both State and Federal Congresses, that process should be reserved for only fundamental or structural changes. Judicial activism, by way of Supreme Court decisions, is a method best applied to the protection of people’s rights.

Created2021-05