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Description
The Transonic Area Rule, developed by Richard T. Whitcomb in the early 1950s, revolutionized high-speed flight because its insight allowed engineers to reduce and/or delay the transonic drag rise. To this day, it is the rationale behind “coke-bottle” sculpturing (indenting the aircraft fuselage at the wing-fuselage junction) to alter the cross-sectional area development of the body. According to Whitcomb, this indentation is meant to create a smoother transition of cross-sectional area development of the body and consequently would reduce the number of shocks on the body, their intensity, and their shock pattern complexity. Along with this, modeling of a geometry’s transonic drag rise could be simplified by creating a comparable body of revolution with the same cross-sectional area development as the original geometry. Thus, the Transonic Area Rule has been advertised as an aerodynamic multitool. This new work probes the underlying mechanics of the Transonic Area Rule and determines just how accurate it is in producing its advertised results. To accomplish this, several different wave-drag approximation methods were used to replicate and compare the results presented in Whitcomb’s famous 1952 report16. These methods include EDET (Empirical Drag Estimation Technique)4, D2500 (Harris Wave Drag program)6, and CFD (Computational Fluid Dynamics) analysis through SU25. Overall drag increment data was collected for comparison with Whitcomb’s data. More in-depth analysis was then done on the flow conditions around the geometries using CFD solution plots.
After analysis of the collected data was performed, it was discovered that this data argued against Whitcomb’s comparable body of revolution claim as no cases were demonstrated where the comparable body and original body yielded similar drag rise characteristics. Along with this, shock structures and patterns were not simplified in two of the three cases observed and were instead complicated even further. The only exception to this observation was the swept wing, cylindrical body in which all shocks were virtually eliminated at all observed Mach numbers. For the reduced transonic drag rise claim, the data argued in favor of this as the drag rise was indeed reduced for the three observed geometries, but only for a limited Mach number range.
ContributorsArmenta, Francisco Xavier (Author) / Takahashi, Timothy T (Thesis advisor) / Kim, Jeonglae (Committee member) / Rodi, Patrick (Committee member) / Arizona State University (Publisher)
Created2021
Description
The phase change process of freezing water is an important application in several fields such as ice making, food freezing technologies, pharmaceuticals etc. Due to the widespread usage of ice-related products, process improvements in this technology can potentially lead to substantial energy savings. After studying the freezing process of water, the supercooling phenomenon was found to occur which showed a negative effect. Therefore, ultrasound was proposed as a technique to reduce the supercooling effect and improve the heat transfer rate. An experimental study was conducted to analyze the energy expenditures in the freezing process with and without the application of ultrasound. After a set of preliminary experiments, an intermittent application of ultrasound at 10W & 3.5W power levels were found to be more effective than constant-power application, and were explored in further detail. The supercooling phenomenon was thoroughly studied through iterative experiments. It was also found that the application of ultrasound during the freezing process led to the formation of shard-like ice crystals. From the intermittent ultrasound experiments performed at 10W and 3.5W power levels, percentage energy enhancements relative to no ultrasound of 8.9% ± 12.4% and 11.9% ± 24.6% were observed, respectively.
ContributorsSubramanian, Varun (Author) / Phelan, Patrick (Thesis advisor) / Calhoun, Ronald (Committee member) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2021
Description
Hydration status serves as an essential pillar of human health. Adequate hydration reduces cardiovascular strain, improves the body's ability to thermoregulate, stabilizes mood, and may reduce the risk of physiologic diseases like that of diabetes and urolithiasis. While many studies have shown the importance of adequate fluid intake on hydration status, very few have investigated the influence of dietary food moisture on hydration status. This study collected daily food diaries, daily fluid diaries, and spot urine samples over a 24hr period from 694 participants in Northwest Arkansas participating in the HYBISKUS study. Fluid and food diaries were logged in NDSR and analyzed using JMP while combined spot urine samples were analyzed using a freezing point depression osmometer to retrieve 24hr urine osmolality. Urine osmolality data was extracted from 24hr urine samples and used as the hydration status biomarker for study participants. The average contributions of water from fluids and foods in participants was 79.3 ±9.6% and 20.7 ±9.5% respectively. This study found that dietary food moisture has a significant effect on hydration status in adults with no specific macronutrient groups take precedence over any others in regard to dietary food moisture contributions. These results suggest that there are legitmate reasons to consider dietary food moisture intake when water intake recommendations are made for adults attempting to optimize health or prepare for physical exercise.
ContributorsKleinschmidt, Hunter (Author) / Kavouras, Stavros SK (Thesis advisor) / Sweazea, Karen KS (Committee member) / Katsanos, Christos CK (Committee member) / Arizona State University (Publisher)
Created2019
Description
Personal training is a growing industry as individuals across the U.S. face increasing levels of physical and psychological health issues. Hiring a certified personal trainer (CPT) presents an opportunity to not only become healthier, but also to grow one’s knowledge and abilities; researchers refer to this process as self-expansion. This research sought to specify a path model of the self-expansion process clients experience while training with their CPT. Secondly, this research described clients’ self-reported disclosure patterns with their CPT. Using Amazon’s Mechanical Turk and ResearchMatch, the study sampled N = 392 U.S. residents who reported training with a CPT. Results from the path analysis indicated poor global fit; however, local fit supported several statistically significant paths. Clients’ level of internal motivation was positively associated with their self-disclosure, self-expansion, and self-pruning. Clients’ self-disclosure was positively associated with perceived closeness with their CPT. Contrary to prediction, clients’ perceived closeness was negatively associated with perceived support from their CPT. However, clients’ perceived closeness and perceived levels of support were both positively associated with their reported levels of self-expansion. Regarding clients’ disclosures, results indicated that clients primarily discuss physical training, diet and nutrition, and health concerns. Thematic analysis of self-reported disclosure examples revealed discussion topics including body dysmorphia, loss and grief, mental health, personal relationships, physical health, professionalism, support seeking, trainer sharing, and trust. Theoretical implications for the self-expansion model include support for additional variables in the self-expansion process, including motivation, self-disclosure, perceived support, and self-pruning. Additionally, practical recommendations for CPTs include an awareness of the type of relationship that clients may desire, as closeness may inhibit perceptions of support with training. Further, CPTs should be aware of the disclosures they may encounter, as clients may share intimate information and seek social support. As such, training programs should include sections on active listening and empathy and require CPTs to be knowledgeable of community resources in the event of a disclosure that presents a serious health risk to the client. Additional research is necessary, particularly to investigate closeness in the self-expansion process, as it did not function as expected within service and professional relationships.
ContributorsShufford, Kevin Nelson (Author) / Adame, Bradley (Thesis advisor) / Randall, Ashley K (Thesis advisor) / Mongeau, Paul (Committee member) / Arizona State University (Publisher)
Created2021
Description
Abstract
The following research addresses some of the contemporary problems that individuals experiencing homelessness face; specifically, investigating the decision to forgo shelter services and spend nights in places unfit for human inhabitation, a phenomenon known as sleeping rough. The paper begins with a broad look at the historical roots of homelessness, urbanization and the failure of mental health services, before exploring past attempts at answering the research question, why do the homeless choose to sleep rough? Several seminal studies, most of which were performed in large New York City shelters, gave context to the dangers present within shelters, but, due to both their location and methodologies, failed to capture the nuances of decision making for individuals experiencing homelessness. In order to expand the literature’s understanding of homelessness and the decision to forgo shelters, I conducted 23 in-depth interviews with various individuals embedded in the homeless culture in Phoenix, Arizona, including those experiencing homelessness, shelter employees, service providers, and the police squad designated to work the shelter beat. This thesis also provides information about the unique circumstances of Phoenix shelter services, the majority of which are housed on the Human Services Campus, a cluster of services specialized for homeless outreach. To supplement the information gathered through in-depth interviews, I analyzed crime maps of the Human Services Campus. This information, coupled with the in-depth interviews, helps explain that the homeless avoid the shelter services for a variety of reasons. These include concerns for safety, freedom, and personal property, as well as a longing to maintain dignity and avoid confrontation with shelter staff and security. Mental health and substance abuse implications are also discussed.
ContributorsHughes, Andrew David (Author) / Scott, Michael (Thesis advisor) / Maguire, Edward (Committee member) / Telep, Cody (Committee member) / Arizona State University (Publisher)
Created2021
Description
Academic advisors play a critical role in student success within United States institutions of higher education. Although uniquely positioned to contribute to important institutional and student outcomes, academic advising is identified in the literature as an emerging profession, often delegitimizing advisor authority and limiting their contribution to institutional objectives. A review of the literature explores the history academic advising, and the current state of professionalization of the field. Additionally, entrepreneurial mindset is introduced as a framework of practice for professional agency. As a field working to professionalize itself within the higher education context, academic advisors must be able to fully participate and contribute to the process of developing innovative practices within the contexts of their institutions. This mixed-methods study drew upon proactive work behavior as defined by Hackman and Oldham to understand how academic advisors demonstrate and perceive their professional agency and ability to make decisions when working with students in the context of their role. Findings suggest professional agency as a construct exists not as a stand-alone concept, but rather as part of an ecosystem within the institution that includes layered systems, structures, and cultures which influence advisor behaviors and how they navigate decision-making. Implications include considerations for academic advising leaders and administrators, specifically related to departmental structures and advisor perceptions of their professional agency. This study contributes to the advising literature in the area of professionalization, with implications for scholarship and practice that can address gaps in the current scholarship.
ContributorsRudd, Melissa (Author) / Basile, Carole (Thesis advisor) / Kim, Jeongeun (Committee member) / Mcintyre, Lisa (Committee member) / Arizona State University (Publisher)
Created2021
Description
Nohokáá Dine’é Diyinii’s (Empowered Earth Surface People, Diné People) story begins with the origin of the cosmos as detailed in Diné emergence narratives, and continues in Diné ceremonial songs, film, and poetry. Diné people’s emergence narratives describe how life moved through the four worlds and how Changing Woman brought Diné people into existence. In the present, Diné people often tell stories against violent colonial domination that aims to unsettle the hope and safety that undergirds their life and prosperity. Through their stories, Diné people bring their past and present together to make futures where Diné life can flourish. Each dissertation chapter explores the contours of storytelling as imagination, power, and future-making through selected Diné stories. Chapter 1 draws from the story of Gus Bighorse as set forth in his as-told-to autobiography (1990). The chapter describes how this Diné warrior, who survived the 1860s forced removal of Diné people, spoke from the heart to tell of a future beyond the US Cavalry’s violence. Such future-focused storying illustrates how Diné people apply elements of Sa’ah’ Naghai Bike’ Hózhǫ (SNBH) in the present to encourage the people to live. SNBH is a philosophy, worldview, and organizing principle for the underlying power through and by which Diné people imagine, create, remake, and renew our reality to realize hózhǫ, beauty. Chapter 2 examines the critical discourse within and around the 2014 Navajo election language fluency controversy that led to Christopher L. Clark Deschene’s removal from the general election ballot. Chapter 3 analyzes the hooghan and the Treaty of 1868 to show how construction in the United States always has sustained and marked the permanence of settler colonialism as white colonizers usurped Diné people’s lands and destroyed their homes. Chapter 4 employs the concept of feminist rehearsal to map the production of life and death in the border town of Gallup. This chapter interweaves the author’s family’s border town experience, the Nááhwíiłbįįhí Story, and Sydney Freeland’s feature film Drunktown’s Finest (2014). Chapter 5, an examination of Diné narratives of catastrophe and emergence, establishes a Diné-based approach to the threat of removal that climate change imposes.
ContributorsClark, Jerome (Author) / Horan, Elizabeth (Thesis advisor) / Bebout, Lee (Committee member) / Fonseca-Chávez, Vaness (Committee member) / Yazzie, Melanie K. (Committee member) / Arizona State University (Publisher)
Created2021
Description
Touch plays a vital role in maintaining human relationships through social andemotional communications. This research proposes a multi-modal haptic display
capable of generating vibrotactile and thermal haptic signals individually and simultaneously.
The main objective for creating this device is to explore the importance
of touch in social communication, which is absent in traditional communication
modes like a phone call or a video call. By studying how humans interpret
haptically generated messages, this research aims to create a new communication
channel for humans. This novel device will be worn on the user's forearm and has
a broad scope of applications such as navigation, social interactions, notifications,
health care, and education. The research methods include testing patterns in the
vibro-thermal modality while noting its realizability and accuracy. Different patterns
can be controlled and generated through an Android application connected to
the proposed device via Bluetooth. Experimental results indicate that the patterns
SINGLE TAP and HOLD/SQUEEZE were easily identifiable and more relatable to
social interactions. In contrast, other patterns like UP-DOWN, DOWN-UP, LEFTRIGHT,
LEFT-RIGHT, LEFT-DIAGONAL, and RIGHT-DIAGONAL were less
identifiable and less relatable to social interactions. Finally, design modifications
are required if complex social patterns are needed to be displayed on the forearm.
ContributorsGharat, Shubham Shriniwas (Author) / McDaniel, Troy (Thesis advisor) / Redkar, Sangram (Thesis advisor) / Zhang, Wenlong (Committee member) / Arizona State University (Publisher)
Created2021
Description
Exposure to social and ecological adversity during sensitive windows of development often leadto disadvantageous outcomes in adulthood such as reduced social connectedness and shorter lifespan. Consequences of early life adversity can persist across generations. The mother is a crucial component of the early life environment for mammals and plays an important role in shaping offspring development. The mechanisms underlying the associations between early life adversity, adult outcomes, and transgenerational effects are not well established, and the complexities of how early life environments shape the ways offspring prioritize different dimensions of development are only beginning to be understood. This dissertation leverages longitudinal data, detailed behavioral observations, fecal hormone sampling, and noninvasive estimates of infant body size to assess how early life experiences shape development and adult outcomes in a wild population of olive baboons (Papio anubis) in Laikipia, Kenya. Four dissertation papers address: 1) the relationship between a mother’s early life adversity and her maternal effort, physiology, and offspring survival; 2) how the maternal environment shapes the ways developing offspring allocate resources among play, behavioral independence, and growth; 3) the role of interaction style in mediating the relationship between early life adversity and adult female sociability; and 4) the relative importance of female competition over food, mates, and male caretakers. Results of these papers show early life adversity can have lasting consequences on maternal effort and physiology, which in turn shape offspring developmental trajectories. Females who experienced early life adversity were less likely to develop an interaction style that was associated with sociability. Finally, the energetic costs of lactation were the primary driver of female competition, and in light of findings in chacma and yellow baboons, this indicates evolution has finely tuned female baboons’ responses to the social and ecological pressures of their local environments. To better understand the complexities of early life experiences and developmental trajectories, it is important to leverage longitudinal data and create comprehensive models of the maternal environment and infant development.
ContributorsPatterson, Sam K (Author) / Silk, Joan (Thesis advisor) / Hinde, Katie (Committee member) / Langergraber, Kevin (Committee member) / Arizona State University (Publisher)
Created2021
Description
Glioblastoma multiforme (GBM) is an aggressive brain cancer without effectivetreatment options, leaving patient survival rates extremely low.
HDAC1 knockdown was found to initiate an invasive phenotype in vivo,
particularly within the BT145 human glioma stem cell (hGSC) line. Analysis through RNA
sequencing (RNA-seq) gene expression and regulatory networks found both CEBPβ, a
known transcription factor (TF) involved in cellular invasion, and the STAT3 pathway, a
notorious genetic component of GBM, were differentially expressed in BT145 hGSCs
after HDAC1 knockdown. Furthermore, overlap of genes regulated by CEBPβ and
STAT3 indicate the CEBPβ/STAT3 pathway may be involved in the observed BT145-
specific invasive phenotype.
The SYstems Genetics Network AnaLysis (SYGNAL) pipeline was applied to
construct sex-specific gene regulatory networks from The Cancer Genome Atlas (TCGA)
GBM patient expression data. Unique bicluster eigengenes were discovered separately
for all, female, and male patients. Through the application of these bicluster eigengenes
to a GBM cohort with multiparametric magnetic resonance imaging (mpMRI) localized
biopsies, sex-specific associations between bicluster expression, mpMRI readout, and
hallmarks of cancer were determined. Distinctive cancer functions were revealed
transcriptionally through bicluster expression, and connected to a unique mpMRI feature.
Specifically, SPGRC mpMRI indicated a strong signal for both immune hallmarks
(evading immune detection and tumor-promoting inflammation). At the same time, MD
mpMRI displayed a tendency toward sustained angiogenesis, possibly signaling the
formation of new blood vessels. Uncovering each mpMRI feature’s underlying biological
processes enables improved GBM diagnosis and treatment utilizing an individualized,
non-invasive approach.
ContributorsLewis, Erika (Author) / Plaisier, Christopher L (Thesis advisor) / Nikkhah, Medhi (Committee member) / Hu, Leland (Committee member) / Arizona State University (Publisher)
Created2021