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Description
Damage detection in heterogeneous material systems is a complex problem and requires an in-depth understanding of the material characteristics and response under varying load and environmental conditions. A significant amount of research has been conducted in this field to enhance the fidelity of damage assessment methodologies, using a wide range

Damage detection in heterogeneous material systems is a complex problem and requires an in-depth understanding of the material characteristics and response under varying load and environmental conditions. A significant amount of research has been conducted in this field to enhance the fidelity of damage assessment methodologies, using a wide range of sensors and detection techniques, for both metallic materials and composites. However, detecting damage at the microscale is not possible with commercially available sensors. A probable way to approach this problem is through accurate and efficient multiscale modeling techniques, which are capable of tracking damage initiation at the microscale and propagation across the length scales. The output from these models will provide an improved understanding of damage initiation; the knowledge can be used in conjunction with information from physical sensors to improve the size of detectable damage. In this research, effort has been dedicated to develop multiscale modeling approaches and associated damage criteria for the estimation of damage evolution across the relevant length scales. Important issues such as length and time scales, anisotropy and variability in material properties at the microscale, and response under mechanical and thermal loading are addressed. Two different material systems have been studied: metallic material and a novel stress-sensitive epoxy polymer.

For metallic material (Al 2024-T351), the methodology initiates at the microscale where extensive material characterization is conducted to capture the microstructural variability. A statistical volume element (SVE) model is constructed to represent the material properties. Geometric and crystallographic features including grain orientation, misorientation, size, shape, principal axis direction and aspect ratio are captured. This SVE model provides a computationally efficient alternative to traditional techniques using representative volume element (RVE) models while maintaining statistical accuracy. A physics based multiscale damage criterion is developed to simulate the fatigue crack initiation. The crack growth rate and probable directions are estimated simultaneously.

Mechanically sensitive materials that exhibit specific chemical reactions upon external loading are currently being investigated for self-sensing applications. The "smart" polymer modeled in this research consists of epoxy resin, hardener, and a stress-sensitive material called mechanophore The mechanophore activation is based on covalent bond-breaking induced by external stimuli; this feature can be used for material-level damage detections. In this work Tris-(Cinnamoyl oxymethyl)-Ethane (TCE) is used as the cyclobutane-based mechanophore (stress-sensitive) material in the polymer matrix. The TCE embedded polymers have shown promising results in early damage detection through mechanically induced fluorescence. A spring-bead based network model, which bridges nanoscale information to higher length scales, has been developed to model this material system. The material is partitioned into discrete mass beads which are linked using linear springs at the microscale. A series of MD simulations were performed to define the spring stiffness in the statistical network model. By integrating multiple spring-bead models a network model has been developed to represent the material properties at the mesoscale. The model captures the statistical distribution of crosslinking degree of the polymer to represent the heterogeneous material properties at the microscale. The developed multiscale methodology is computationally efficient and provides a possible means to bridge multiple length scales (from 10 nm in MD simulation to 10 mm in FE model) without significant loss of accuracy. Parametric studies have been conducted to investigate the influence of the crosslinking degree on the material behavior. The developed methodology has been used to evaluate damage evolution in the self-sensing polymer.
ContributorsZhang, Jinjun (Author) / Chattopadhyay, Aditi (Thesis advisor) / Dai, Lenore (Committee member) / Jiang, Hanqing (Committee member) / Papandreou-Suppappola, Antonia (Committee member) / Rajadas, John (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Composite materials are increasingly being used in aircraft, automobiles, and other applications due to their high strength to weight and stiffness to weight ratios. However, the presence of damage, such as delamination or matrix cracks, can significantly compromise the performance of these materials and result in premature failure. Structural components

Composite materials are increasingly being used in aircraft, automobiles, and other applications due to their high strength to weight and stiffness to weight ratios. However, the presence of damage, such as delamination or matrix cracks, can significantly compromise the performance of these materials and result in premature failure. Structural components are often manually inspected to detect the presence of damage. This technique, known as schedule based maintenance, however, is expensive, time-consuming, and often limited to easily accessible structural elements. Therefore, there is an increased demand for robust and efficient Structural Health Monitoring (SHM) techniques that can be used for Condition Based Monitoring, which is the method in which structural components are inspected based upon damage metrics as opposed to flight hours. SHM relies on in situ frameworks for detecting early signs of damage in exposed and unexposed structural elements, offering not only reduced number of schedule based inspections, but also providing better useful life estimates. SHM frameworks require the development of different sensing technologies, algorithms, and procedures to detect, localize, quantify, characterize, as well as assess overall damage in aerospace structures so that strong estimations in the remaining useful life can be determined. The use of piezoelectric transducers along with guided Lamb waves is a method that has received considerable attention due to the weight, cost, and function of the systems based on these elements. The research in this thesis investigates the ability of Lamb waves to detect damage in feature dense anisotropic composite panels. Most current research negates the effects of experimental variability by performing tests on structurally simple isotropic plates that are used as a baseline and damaged specimen. However, in actual applications, variability cannot be negated, and therefore there is a need to research the effects of complex sample geometries, environmental operating conditions, and the effects of variability in material properties. This research is based on experiments conducted on a single blade-stiffened anisotropic composite panel that localizes delamination damage caused by impact. The overall goal was to utilize a correlative approach that used only the damage feature produced by the delamination as the damage index. This approach was adopted because it offered a simplistic way to determine the existence and location of damage without having to conduct a more complex wave propagation analysis or having to take into account the geometric complexities of the test specimen. Results showed that even in a complex structure, if the damage feature can be extracted and measured, then an appropriate damage index can be associated to it and the location of the damage can be inferred using a dense sensor array. The second experiment presented in this research studies the effects of temperature on damage detection when using one test specimen for a benchmark data set and another for damage data collection. This expands the previous experiment into exploring not only the effects of variable temperature, but also the effects of high experimental variability. Results from this work show that the damage feature in the data is not only extractable at higher temperatures, but that the data from one panel at one temperature can be directly compared to another panel at another temperature for baseline comparison due to linearity of the collected data.
ContributorsVizzini, Anthony James, II (Author) / Chattopadhyay, Aditi (Thesis advisor) / Fard, Masoud (Committee member) / Papandreou-Suppappola, Antonia (Committee member) / Arizona State University (Publisher)
Created2012
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Description
The National Basketball Association (NBA) is one of the Big Four Sporting Leagues of US Professional Sports. In recent years, the NBA has enjoyed milestone seasons in both attendance and television ratings, resulting in steady increases to both, over the previous decade. (Morgan, 2017) This surge can be attributed in

The National Basketball Association (NBA) is one of the Big Four Sporting Leagues of US Professional Sports. In recent years, the NBA has enjoyed milestone seasons in both attendance and television ratings, resulting in steady increases to both, over the previous decade. (Morgan, 2017) This surge can be attributed in part to the integration of "cultural recognition" initiatives and the overall message of inclusivity on the part of NBA franchises, with their respective promotions and advertisements such as television, social media, radio, etc. Heritage Nights, such as "Noche Latina," among other variants in the NBA, typically feature culturally influenced changes to team logos, giveaways, and other consumer offerings. In markets where Hispanics make up a significant percentage of the fan-base, such as Phoenix, NBA franchises such as the Phoenix Suns must ascertain the financial or perceptual impacts, associated with risks of stereotyping, offending or otherwise unintentionally alienating different categories of fans. To this end, data was collected from the local NBA franchises' fanbase, specifically Phoenix Suns season-ticket holders, and was statistically checked for significant relationships between both categories of fans and several different variables. This analysis found that only $192K in revenue is being missed through the investment of Heritage Nights, and that fan perceptions of stereotypical or offensive giveaways and practices have no significant effect on game or event attendance, despite the stereotypes toward giveaways and practices still being present. Implications of this study provide possible next steps for the Suns and continue to widen the scope of demographical sports marketing both in professional basketball and beyond.
ContributorsGibbens, Patrick Alexander (Author) / Eaton, John (Thesis director) / McIntosh, Daniel (Committee member) / Department of Supply Chain Management (Contributor) / School of Music (Contributor) / Department of Marketing (Contributor) / W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This paper is intended to identify a correlation between the winning percentage of sports teams in the four major professional sports leagues in the United States and the GDP per capita of their respective cities. We initially compiled fifteen years of franchise performance along with economic data from the Federal

This paper is intended to identify a correlation between the winning percentage of sports teams in the four major professional sports leagues in the United States and the GDP per capita of their respective cities. We initially compiled fifteen years of franchise performance along with economic data from the Federal Reserve Bank of St. Louis to analyze this relationship. After converting the data into a language recognized by Stata, the regression tool we used, we ran multiple regressions to find relevant correlations based off of our inputs. This paper will show the value of the economic impact of strong or weak performance throughout various economic cycles through data analysis and conclusions drawn from the results of the regression analysis.
ContributorsAndl, Tyler (Co-author) / Shirk, Brandon (Co-author) / Goegan, Brian (Thesis director) / Eaton, John (Committee member) / School of Accountancy (Contributor) / Department of Finance (Contributor) / Department of Supply Chain Management (Contributor) / Department of Information Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
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Description
The vastly growing field of supercomputing is in dire need of a new measurement system to optimize JMRAM (Josephson junction magnetoresistive random access memory) devices. To effectively measure these devices, an ultra-low-noise, low cost cryogenic dipping probe with a dynamic voltage range is required. This dipping probe has been designed

The vastly growing field of supercomputing is in dire need of a new measurement system to optimize JMRAM (Josephson junction magnetoresistive random access memory) devices. To effectively measure these devices, an ultra-low-noise, low cost cryogenic dipping probe with a dynamic voltage range is required. This dipping probe has been designed by ASU with <100 nVp-p noise, <10 nV offsets, 10 pV to 16 mV voltage range, and negligible thermoelectric drift. There is currently no other research group or company that can currently match both these low noise levels and wide voltage range. Two different dipping probes can be created with these specifications: one for high-use applications and one for low-use applications. The only difference between these probes is the outer shell; the high-use application probe has a shell made of G-10 fiberglass for a higher price, and the low-use application probe has a shell made of AISI 310 steel for a lower price. Both types of probes can be assembled in less than 8 hours for less than $2,500, requiring only soldering expertise. The low cost and short time to create these probes makes wide profit margins possible. The market for these cryogenic dipping probes is currently untapped, as most research groups and companies that use these probes build their own, which allows for rapid business growth. These potential consumers can be easily reached by marketing these probes at superconducting conferences. After several years of selling >50 probes, mass production can easily become possible by hiring several technicians, and still maintaining wide profit margins.
ContributorsHudson, Brooke Ashley (Author) / Adams, James (Thesis director) / Anwar, Shahriar (Committee member) / Materials Science and Engineering Program (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
The ability to draft and develop productive Major League players is vital to the success of any MLB organization. A core of cost-controlled, productive players is as important as ever with free agent salaries continuing to rise dramatically. In a sport where mere percentage points separate winners from losers at

The ability to draft and develop productive Major League players is vital to the success of any MLB organization. A core of cost-controlled, productive players is as important as ever with free agent salaries continuing to rise dramatically. In a sport where mere percentage points separate winners from losers at the end of a long season, any slight advantage in identifying talent is valuable. This study examines the 2004-2008 MLB Amateur Drafts in order to analyze whether certain types of prospects are more valuable selections than others. If organizations can better identify which draft prospects will more likely contribute at the Major League level in the future, they can more optimally spend their allotted signing bonus pool in order to acquire as much potential production as possible through the draft. Based on the data examined, during these five drafts high school prospects provided higher value than college prospects. While college players reached the Majors at a higher rate, high school players produced greater value in their first six seasons of service time. In the all-important first round of the draft, where signing bonuses are at their largest, college players proved the more valuable selection. When players were separated by position, position players held greater expected value than pitchers, with corner infielders leading the way as the position group with the highest expected value. College players were found to provide better value than high school players at defensively demanding positions such as catcher and middle infield, while high school players were more valuable among outfielders and pitchers.
ContributorsGildea, Adam Joseph (Author) / Eaton, John (Thesis director) / McIntosh, Daniel (Committee member) / Department of Economics (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Abstract My documentary is about the concussion detection study with Arizona State Football, Translational Genomics Research Institute (TGen), Riddell and the Barrow Neurological Institute. Football players voluntarily participate in the study that aims to identify a biomarker released from the brain to identify if a player has suffered from a

Abstract My documentary is about the concussion detection study with Arizona State Football, Translational Genomics Research Institute (TGen), Riddell and the Barrow Neurological Institute. Football players voluntarily participate in the study that aims to identify a biomarker released from the brain to identify if a player has suffered from a concussion. The study uses blood, urine and saliva samples, along with head impact data from Riddell's Sideline Response System. The study is also focusing on the impact of sub-concussive hits and the effects. According to the Barrow Neurological Institute, 84% of respondents believe concussions are "a serious medical condition," and a third of Valley parents will not let their children play football. I interviewed an ASU football player who participated in the study and found out about his experiences with concussions. The severity of concussions has received a lot of attention in recent years, and this study hopes to mitigate concussions symptoms and the fear of concussions. According to the 2015 NFL Health and Safety Report, since 2012 the NFL reported concussions were down by 35%. I interviewed the TGen leaders of the study and the neurologist at the Barrow Concussion and Brain Injury center involved in the study to find out how they plan to find a biomarker and use it to develop an objective way to diagnose concussions. An example of a possible objective test is a mouthguard that changes from clear to blue after a player sustained a hit that resulted in a concussion. The 2015-2016 ASU football season marked the study's third year of research. At the time of my documentary, the study had no timeline to release data.
ContributorsSeki, Katryna Marie (Author) / Lodato, Mark (Thesis director) / Kurland, Brett (Committee member) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Each year, a select few minor league baseball players are chosen to attend the Arizona Fall League, a development league within Major League Baseball that hones the next generation of players, coaches, managers, and even umpires. These players make up the top talent currently in the minor leagues from each

Each year, a select few minor league baseball players are chosen to attend the Arizona Fall League, a development league within Major League Baseball that hones the next generation of players, coaches, managers, and even umpires. These players make up the top talent currently in the minor leagues from each of Major League Baseball's 30 organizations. Of the thousands in the minors, just seven players from each organization can go to this extra six-week season, and learn to play alongside the best future talent the sport has to offer. On Deck: Inside the Arizona Fall League is a short documentary that looks at some of these players, as they continue their baseball journey that they hope leads them one day to the Majors. The documentary can be viewed online at https://youtu.be/jkggYiDtn14 or nicolesheraefox.com
ContributorsFox, Nicole Sherae (Author) / Lodato, Mark (Thesis director) / Kurland, Brett (Committee member) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Although wind turbine bearings are designed to operate 18-20 years, in the recent years premature failure among these bearings has caused this life to reduce to as low as a few months to a year. One of the leading causes of premature failure called white structure flaking is a mechanism

Although wind turbine bearings are designed to operate 18-20 years, in the recent years premature failure among these bearings has caused this life to reduce to as low as a few months to a year. One of the leading causes of premature failure called white structure flaking is a mechanism that was first cited in literature decades ago but not much is understood about it even today. The cause of this mode of failure results from the initiation of white etched cracks (WECs). In this report, different failure mechanisms, especially premature failure mechanisms that were tested and analyzed are demonstrated as a pathway to understanding this phenomenon. Through the use of various tribometers, samples were tested in diverse and extreme conditions in order to study the effect of these different operational conditions on the specimen. Analysis of the tested samples allowed for a comparison of the microstructure alterations in the tested samples to the field bearings affected by WSF.
ContributorsSharma, Aman (Author) / Foy, Joseph (Thesis director) / Adams, James (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2015-05
Description
This project, which consists of a review article and an applied creative project, proposes mirror neurons as being a physiological mechanism for motor imagery. The review article highlights similarities between motor imagery research and research on mirror neurons. The research is roughly divided into three types of studies: neuroimaging studies,

This project, which consists of a review article and an applied creative project, proposes mirror neurons as being a physiological mechanism for motor imagery. The review article highlights similarities between motor imagery research and research on mirror neurons. The research is roughly divided into three types of studies: neuroimaging studies, transcranial magnetic stimulation (TMS) and electromyography (EMG) studies, and electroencephalography (EEG) studies. The review also discusses the associative hypothesis of mirror neuron origin as support for the hypothesis and concludes with an assessment of conflicting research and the limitations of the hypothesis. The applied creative project is an instructional brochure, aimed at anyone who teaches motor skills, such as dance teachers or sports coaches. The brochure takes the academic content of the review and presents it in a visually pleasing, reader-friendly fashion in an effort to educate the intended audience and make the research more accessible. The brochure also prescribes research-based suggestions for how to use motor imagery during teaching sessions and how to get the best benefits from it.
ContributorsNgai, Valerie Christina (Author) / Hoffner, Kristin (Thesis director) / Glenberg, Arthur (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor) / Department of Psychology (Contributor)
Created2015-05