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- Creators: Barrett, The Honors College
Description
Digital to analog converters (DACs) find widespread use in communications equipment. Most commercially available DAC's which are intended to be used in transmitter applications come in a dual configuration for carrying the in phase (I) and quadrature (Q) data and feature on chip digital mixing. Digital mixing offers many benefits concerning I and Q matching but has one major drawback; the update rate of the DAC must be higher than the intermediate frequency (IF) which is most commonly a factor of 4. This drawback motivates the need for interpolation so that a low update rate can be used for components preceding the DACs. In this thesis the design of an interpolating DAC integrated circuit (IC) to be used in a transmitter application for generating a 100MHz IF is presented. Many of the transistor level implementations are provided. The tradeoffs in the design are analyzed and various options are discussed. This thesis provides a basic foundation for designing an IC of this nature and will give the reader insight into potential areas of further research. At the time of this writing the chip is in fabrication therefore this document does not contain test results.
ContributorsNixon, Cliff (Author) / Bakkaloglu, Bertan (Thesis advisor) / Arizona State University (Publisher)
Created2013
Description
University students currently lack sufficient knowledge and resources needed to support healthy eating patterns and nutrition. Comparison of the number of registered dietitians that are available to all students, along with the number of wellness events that are held at each university within the Pacific-12 conference will help determine which schools are best able to support their students' needs. Data was collected using a Google forms survey sent via email to wellness directors of each of the universities in the Pac-12 conference. Eight out of the twelve schools in the conference responded to the survey. The average number of dietitians available to all students (regardless of athlete status) was found to be 1.43 dietitians. Of the schools that responded, the University of Colorado, Boulder, has the most resources dedicated to student nutrition wellness with three dietitians available for all undergraduate students, free dietitian services, and approximately 150 wellness events each year. The success of available nutrition wellness resources was inconclusive as schools did not provide the information regarding student utilization and attendance. Future university promoted nutrition wellness programs should increase the number of affordable dietitians and total wellness events, as well as promote student health services through social media platforms to improve student nutrition knowledge and usage of resources.
ContributorsCurtin, Anne Clare (Author) / Dixon, Kathleen (Thesis director) / McCoy, Maureen (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Abstract Ambrofit is a company I founded in February 2014 whose overarching goal is to bridge the gap between science and supplements. This thesis project is as an extension of, and upgrade to, Ambrofit's work. The project begins with a brief discussion of the supplement industry, motivating the problem which myself and Ambrofit are trying to solve. It addresses the shortcomings of the industry, its regulatory history, and the causal factors which create the industry's environment. As the main part of the project, I design and execute a systematic, evidence-based nutritional product formulation process to create an scientifically sound ergogenic aid which can reliably accelerate training adaptations. The methodology starts with a round of exploratory research to discover potential ingredients then systematically analyzes each ingredient in multiple rounds of effectiveness and safety screenings until the final formula can be synthesized. Ergogenics were the focus of this project because Ambrofit's current product is an ergogenic aid, but I will apply this same process to formulate Ambrofit's whole product line in the future. The second arm of the project is a clinical study protocol design - an evidence-based product created from secondary research is a good start, but ultimately, the formula must be validated by direct research. The protocol describes an 8-week study with well-trained subjects which would either support or reject the formula's ability to accelerate anaerobic training adaptations. The project concludes with a discussion and application of Ambrofit's marketing. This part of the project was done with boots-on-the-ground; Ambrofit is already operating commercially, so I was able test marketing ideas live and evaluate their performance.
ContributorsRoper, Jacob William (Author) / Denning, Michael (Thesis director) / Johnston, Carol (Committee member) / Department of Marketing (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Buck converters are a class of switched-mode power converters often used to step down DC input voltages to a lower DC output voltage. These converters naturally produce a current and voltage ripple at their output due to their switching action. Traditional methods of reducing this ripple have involved adding large discrete inductors and capacitors to filter the ripple, but large discrete components cannot be integrated onto chips. As an alternative to using passive filtering components, this project investigates the use of active ripple cancellation to reduce the peak output ripple. Hysteretic controlled buck converters were chosen for their simplicity of design and fast transient response. The proposed cancellation circuits sense the output ripple of the buck converter and inject an equal ripple exactly out of phase with the sensed ripple. Both current-mode and voltage-mode feedback loops are simulated, and the effectiveness of each cancellation circuit is examined. Results show that integrated active ripple cancellation circuits offer a promising substitute for large discrete filters.
ContributorsWang, Ziyan (Author) / Bakkaloglu, Bertan (Thesis director) / Kitchen, Jennifer (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Forty collegiate gymnasts were recruited for a nutrition and health study. Participants must have been at least eighteen years old at Arizona State University (ASU) in the club or team gymnastics program. The Institutional Review Board (IRB) reviewed and accepted my survey in order to hand out to the gymnasts. The ASU club and team coach and the ASU study team also approved my survey. As soon as the survey was approved, it was emailed to all of the gymnasts. ASU gymnasts were surveyed on nutritional knowledge and personal health. Subjects answered a quiz on nutrient needs and serving sizes. Personal questions consisted of height, weight, injuries, body image, and typical meal plans. Gymnasts were given a $10 compensation to increase the participation. We found that only 16% of gymnasts surveyed scored a 70% or higher on their nutritional knowledge. Although these gymnasts do not have adequate knowledge, the majority consume a healthy diet. Diets included fruits, vegetables, protein-rich foods, and few high fat and sugary foods. Four of the gymnasts had one or fewer injuries in the past two years, although, four gymnasts also had three or more injuries. No correlation was found between diet and injuries. There was also no correlation between the gymnast's nutritional knowledge and their health.
ContributorsKugler, Natalie K. (Author) / Levinson, Simin (Thesis director) / Berger, Christopher (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Dogs' health and wellbeing is of great importance to their owners. The most common nutritional problem for pet dogs is obesity, with 22-40% of pet dogs being classified as overweight or obese. With many adverse health effects associated with obesity, this is a major concern for owners and veterinarians. The degree to which dogs enjoy consuming certain foods can have substantial implications for their body weight, so it is important to understand which aspects of foods make them appealing to dogs. This study aimed to determine whether nutritional aspects of commercial dog foods predict dogs' preferences for those foods. It was found that consumption preference is positively correlated with protein content (p < .001), therefore implying that the protein content of commercial dry dog foods may predict dogs' consumption preferences. Consumption preferences were not predicted by other available measures of food content or caloric value. Dogs' preference for foods high in protein content may be due to the satiating effect of protein. Since foods high in protein both reduce the amount of energy consumed and are found to be palatable to dogs, high-protein dog foods may offer a way for dog food manufacturers, veterinarians, and pet owners to combat obesity in pet dogs.
ContributorsPrevost, Emily Danielle (Author) / Wynne, Clive (Thesis director) / Hall, Nathaniel (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
According to the CDC, diabetes is the 7th leading cause of death in the U.S. and rates are continuing to rise nationally and internationally. Chronically elevated blood glucose levels can lead to type 2 diabetes and other complications. Medications can be used to treat diabetes, but often have side effects. Lifestyle and diet modifications can be just as effective as medications in helping to improve glycemic control, and prevent diabetes or improve the condition in those who have it. Studies have demonstrated that consuming vinegar with carbohydrates can positively impact postprandial glycemia in diabetic and healthy individuals. Continuous vinegar intake with meals may even reduce fasting blood glucose levels. Since vinegar is a primary ingredient in mustard, the purpose of this study was to determine if mustard consumption with a carbohydrate-rich meal (bagel and fruit juice) had an effect on the postprandial blood glucose levels of subjects. The results showed that mustard improved glycemia by 17% when subjects consumed the meal with mustard as opposed to the control. A wide variety of vinegars exists. The defining ingredient in all vinegars is acetic acid, behind the improvement in glycemic response observed with vinegar ingestion. Vinegar-containing foods range from mustard, to vinaigrette dressings, to pickled foods. The benefits of vinegar ingestion with carbohydrates are dose-dependent, meaning that adding even small amounts to meals can help. Making a conscious effort to incorporate these foods into meals, in addition to an overall healthy lifestyle, could provide an additional tool for diabetics and nondiabetics alike to consume carbohydrates in a healthier manner.
ContributorsJimenez, Gabriela (Author) / Johnston, Carol (Thesis director) / Lespron, Christy (Committee member) / School of Nutrition and Health Promotion (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This project was centered around designing a processor model (using the C programming language) based on the Coldfire computer architecture that will run on third party software known as Open Virtual Platforms. The end goal is to have a fully functional processor that can run Coldfire instructions and utilize peripheral devices in the same way as the hardware used in the embedded systems lab at ASU. This project would cut down the substantial amount of time students spend commuting to the lab. Having the processor directly at their disposal would also encourage them to spend more time outside of class learning the hardware and familiarizing themselves with development on an embedded micro-controller. The model will be accurate, fast and reliable. These aspects will be achieved through rigorous unit testing and use of the OVP platform which provides instruction accurate simulations at hundreds of MIPS (million instructions per second) for the specified model. The end product was able to accurately simulate a subset of the Coldfire instructions at very high rates.
ContributorsDunning, David Connor (Author) / Burger, Kevin (Thesis director) / Meuth, Ryan (Committee member) / Barrett, The Honors College (Contributor) / Computer Science and Engineering Program (Contributor)
Created2014-12
Description
Height is an essential measure for the evaluation of an adult's health, and especially important for the measure of children's health.4 Lasers have been popularly used in many areas such as construction, engineering, government for defense purposes, and for equestrians. Lasers are depended on for their accuracy, reliability, and ease of use.8, 9 It can be reasoned then that lasers should be a reliable way of measuring height, proving to be accurate and easy to use. Currently, stadiometers are the standard way of measuring height. For the study a laser tool was created to measure the volunteers' heights. Volunteers were recruited from a total of four various public sites in different cities. Participants were categorized into three groups, children (ages 2-12), adolescents (13-18), and adults (19+). A total of 128 participants were measured. Results showed a strong positive correlation between measurements of the stadiometer and the laser (figure 3). While there were limitations to this study, results show that a laser may be a validated tool to measure height accurately
ContributorsGarcia-Turner, Vanessa Marie (Author) / Mayol-Kreiser, Sandra (Thesis director) / Johnston, Carol (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor) / Department of Psychology (Contributor)
Created2014-05
Description
The purpose of this thesis is to create an informational book on gluten-free living. It is our hope that by the end of the book readers will have a better understanding that living with a gluten intolerance or auto-immune disorder does not control one's life. Someone just needs to put in a bit more planning and time in order to travel or eat out. The book goes into detail on every condition on the gluten-sensitivity spectrum. It also goes in-depth on medicines, recipes, and travel.
ContributorsSnodgrass, Allison (Co-author) / Snodgrass, Amanda (Co-author) / Johnston, Carol (Thesis director) / Jacobs, Mark (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05