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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

This case study describes an adult patient whose brachial plexus injury was treated with various modalities and exercise. The participant of this study was a 76 year old female who sustained a brachial plexus injury during an elective reverse total shoulder arthroplasty. The initial evaluation reported only passive range of

This case study describes an adult patient whose brachial plexus injury was treated with various modalities and exercise. The participant of this study was a 76 year old female who sustained a brachial plexus injury during an elective reverse total shoulder arthroplasty. The initial evaluation reported only passive range of motion with 90 degrees shoulder flexion, 85 degrees abduction, and 30 degrees external rotation. Muscle testing yielded significantly limited wrist and digit extension strength. Testing of sensation found diminished protective sensation along the median nerve distribution, including the thumb, index finger, and middle finger. Occupational therapy was initiated for postoperative treatment of the shoulder as well as treatment of the brachial plexus palsy. Therapy consisted of static splinting for healing structures and sensory reeducation through massage, finding objects with the eyes occluded, and fluidotherapy. Additionally, various exercises and modalities for improving motion and strength were initiated, including proprioceptive neuromuscular reeducation, passive/active assist/active exercises, dynamic splinting, muscle stimulation, kinesio tape, functional activities, and tendon glides. After five months, active range of motion in the shoulder, elbow, and wrist was finally achieved and median nerve sensation had improved. After nine months, elbow motion was within normal limits and wrist motion had significantly improved. Upon muscle testing, the elbow, forearm, wrist, and hand had made significant gains in strength. However, shoulder strength and motion was still limited. Overall, treatment made a significant improvement in the patient’s functionality.

ContributorsMorlock, Callista (Author) / Ramos, Christopher (Thesis director) / Thomas, Karen (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

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.

ContributorsGarciapena, Danae (Co-author) / Aguiar, Lara (Co-author) / Loebenberg, Abby (Thesis director) / Swanson, Jodi (Committee member) / College of Health Solutions (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

Background: The purpose of this study was to assess the efficacy of a lifestyle intervention on cardiorespiratory fitness in Latino youth with obesity and prediabetes. <br/>Methods: Participants (n=50) in this study were taken from a larger randomized controlled trial (n=180, BMI ≥ 95th percentile). Youth participated in a 6-month lifestyle

Background: The purpose of this study was to assess the efficacy of a lifestyle intervention on cardiorespiratory fitness in Latino youth with obesity and prediabetes. <br/>Methods: Participants (n=50) in this study were taken from a larger randomized controlled trial (n=180, BMI ≥ 95th percentile). Youth participated in a 6-month lifestyle intervention that included physical activity (60 minutes, 3x/week) and nutrition and wellness classes (60 minutes, 1x/week) delivered to families at the Lincoln Family YMCA in Downtown Phoenix. The primary outcome was cardiorespiratory fitness measured at baseline and post-intervention.<br/>Results: The mean BMI for the sample was 33.17 ± 4.54 kg/m2, which put the participants in the 98.4th percentile. At baseline, the mean VO2max was 2737.02 ± 488.89 mL/min. The mean relative VO2max was 30.65 ± 3.87 mL/kg/min. VO2max values significantly increased from baseline to post-intervention (2737.022 ± 483.977 mL/min vs 2932.654 ± 96.062 mL/min, p<0.001). <br/>Conclusion: Culturally-grounded, family-focused lifestyle interventions are a promising approach for improving cardiorespiratory fitness in high-risk youth at risk for diabetes.

ContributorsEstrada, Lourdes Alexa (Author) / Shaibi, Gabriel (Thesis director) / Peña, Armando (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The following paper explores the various effects of stress on the endocrine system. Many understand that being stressed can jeopardize maintaining adequate health, but what specifically happens when humans are stressed? Why does stress affect human health? This paper delves into background information, previous research, and the depths to which

The following paper explores the various effects of stress on the endocrine system. Many understand that being stressed can jeopardize maintaining adequate health, but what specifically happens when humans are stressed? Why does stress affect human health? This paper delves into background information, previous research, and the depths to which stress negatively affects the body. The effects stress has on the endocrine system, specifically on the hypothalamic-pituitary-thyroid axis (HPT) and hypothalamic-pituitary-adrenal axis (HPA), is discussed, and additionally, at home de-stressing methods are researched. The study included a set of participants at Arizona State University. The method took place over the course of 2 weeks: one normal week, and the other with the implementation of a de-stressing method. The normal week involved the participants living their daily lives with the addition of a stress-measuring survey, while the second week involved implementing a de-stressing method and stress-measuring survey. The purpose of this study was to discover if there was a correlation between performing these relaxation activities and decreasing stress levels in ASU students. The results found that students reported they felt more relaxed and calm after the activities. Overall, this thesis provides information and first hand research on the effects of stress and stress-reducing activities and discusses the importance of maintaining lower stress levels throughout everyday life.

ContributorsWeissmann, Megan Diane (Co-author) / Gebara, Nayla (Co-author) / Don, Rachael (Thesis director) / Irving, Andrea (Committee member) / Kizer, Elizabeth (Committee member) / College of Health Solutions (Contributor) / Edson College of Nursing and Health Innovation (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The purpose of this Barrett Thesis Project is to review the existing literature on ACL injuries specifically regarding their risk factors, prevention, and recovery options. The content of the review has been placed into four sections: physiological factors, biomechanical factors, surgery and recovery factors, as well as training factors.

The purpose of this Barrett Thesis Project is to review the existing literature on ACL injuries specifically regarding their risk factors, prevention, and recovery options. The content of the review has been placed into four sections: physiological factors, biomechanical factors, surgery and recovery factors, as well as training factors. Physiological factors look at static structures and their impact on ACL injuries, more specifically, the role that variations on physical structure values can have on injury incidence. Biomechanical factors focus on the ways that movement can contribute to injury and the ways that incorrect movement or unanticipated movement can have on the structures of the knee. Surgery and recovery factors look at surgical techniques that have been used to correct ACL injuries and the details of their function as well as certain surgical techniques that have differing rates of success and how they can impact re-injury and rehabilitation rates. Finally, training factors analyze techniques that can be used in both pre-injury or post-injury situations therefore, this section looks at the ways that training can minimize re-injury as well as work towards preventing the initial injury. Overall, this research review looks at how these factors come together to contribute to an ACL injury and the ways that injury incidence can be minimized. Risk factors come together in order to create an undesirable situation in which the ACL ligament ruptures. These risk factors are either physiological or biomechanical in nature. As a result of injury, certain surgical techniques can be used that impact the success of a patient. Evidence for the benefit of training factors can then be applied in order to reduce injury risk or prevent future injuries.

ContributorsIsrael, Kyle (Co-author) / Fang, Charles (Co-author) / Ramos, Christopher (Thesis director) / Larson, David (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

Background: The US population faces a continual increase in obesity prevalence, raising health concerns due to associated comorbidities ranked as leading causes of preventable, premature death world-wide. Scientists have found a link between obesity-associated conditions and oxidative stress (OS). To date, renewed interest in the effectiveness of dietary regimens in

Background: The US population faces a continual increase in obesity prevalence, raising health concerns due to associated comorbidities ranked as leading causes of preventable, premature death world-wide. Scientists have found a link between obesity-associated conditions and oxidative stress (OS). To date, renewed interest in the effectiveness of dietary regimens in decreasing body weight is a popular research topic. Intermittent fasting (IF) is a popular and promising weight management strategy. To date, there have been no systematic reviews examining whether IF can reduce oxidative stress in overweight/obese adults. <br/><br/>Objective: Conduct a systematic review to evaluate the effects of intermittent fasting (IF) regimens on circulating markers of oxidative stress in overweight/obese adults compared to continuous calorie restriction (CR). <br/><br/>Methods: Databases PubMed, SCOPUS, ProQuest, and Cochrane were searched on February 21, 2021 for eligible articles limiting selection to those in the English language. Predefined search terms and restrictions were applied by two of the authors conducting the search. References from articles generated were also considered. Selected articles were limited to randomized controlled trials (RCTs) and human trials evaluating the effects of intermittent fasting (IF) dietary regimens in comparison to continuous calorie restriction (CR). Study populations considered were limited to those within the range of 18-65 years having a body mass index (BMI) of ≥25 kg/m2 and in otherwise generally good health with the absence of pre-existing acute or chronic conditions. The Academy of Nutrition and Dietetics Evidence Analysis Library Quality Rating Worksheet was used to assess the methodological quality of each of the studies and the Academy of Nutrition and Dietetics Grade Definitions and Conclusion Grading Table were used to appraise the quality of evidence.<br/><br/>Results: Six articles met eligibility criteria and were included in this review. Cumulatively 355 overweight/obese participants were assessed. Quality ratings performed by two of the authors revealed a high-quality rating for all six of the articles. One of the articles reported a significant IF associated difference in circulating 8-isoprostane concentrations and another article reported a significant decrease in circulating oxidative lipoproteins concentrations. The remaining articles showed no significant difference on OS markers following IF. <br/><br/>Conclusions: Based on the six articles included in this systematic review, IF was concluded to have limited impact on reducing circulating markers of OS in overweight/obese adults. Overall, the evidence was heterogeneous in relation to IF interventions and outcomes precluding a meta-analysis. Consequently, evidence to make dietary recommendations for reducing oxidative stress with IF interventions is insufficient at this point.

ContributorsMcevoy, Carissa Nicole (Author) / Sweazea, Karen (Thesis director) / Sears, Dorothy (Committee member) / Mohr, Alex (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

In my undergraduate honors thesis, I strive to convey my idea that dance is more than just movement, it’s one of the many artistic tools used to express emotions; which therefore has the power to storytell without words. It is my hope to create a captivating form of art that

In my undergraduate honors thesis, I strive to convey my idea that dance is more than just movement, it’s one of the many artistic tools used to express emotions; which therefore has the power to storytell without words. It is my hope to create a captivating form of art that you not only view, but can interact and interpret.

ContributorsSawant, Sarika (Author) / Roses-Thema, Cynthia (Thesis director) / Sulikowski, James (Committee member) / College of Health Solutions (Contributor) / School of Music, Dance and Theatre (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05