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  Partner: UNT Libraries
 Decade: 2010-2019
 Degree Level: Master's
 Collection: UNT Theses and Dissertations
161 Glass: Site Specific Music in an Artistic Context
The composition 161 Glass is a 17-minute musical work with percussion, wind and brass instruments in which the intersection of mid-century architecture, and the art and culture of a dynamic city are inextricably linked. Through this paper, I explore the process of composing a musical work in relationship to the significance of site specific context. The paper begins by defining the concept of site specific art works; then reviews the discourse of the intersection of art, music and architecture. I then delve into the cultural and geographic context surrounding this project from the modern era through the present, and how those perspectives apply to the building and my piece. I reveal how the composition relates the musical ideas to the site. Finally, I describe the collaborative process between myself, the musicians and the Dallas Contemporary staff. digital.library.unt.edu/ark:/67531/metadc28472/
A 018μm Cmos Transmitter for Ecg Signals
Electrocardiography (ECG) signal transmitter is the device used to transmit the electrical signals of the heart to the remote machine. These electrical signals are ECG signals caused due to electrical activities in the heart. ECG signals have very low amplitude and frequency; hence amplification of the signals is needed to strengthen the signal. Conversion of the amplified signal into digital information and transmitting that information without losing any data is the key. This information is further used in monitoring the heart. digital.library.unt.edu/ark:/67531/metadc407805/
3GPP Long Term Evolution LTE Scheduling
Future generation cellular networks are expected to deliver an omnipresent broadband access network for an endlessly increasing number of subscribers. Long term Evolution (LTE) represents a significant milestone towards wireless networks known as 4G cellular networks. A key feature of LTE is the implementation of enhanced Radio Resource Management (RRM) mechanism to improve the system performance. The structure of LTE networks was simplified by diminishing the number of the nodes of the core network. Also, the design of the radio protocol architecture is quite unique. In order to achieve high data rate in LTE, 3rd Generation Partnership Project (3GPP) has selected Orthogonal Frequency Division Multiplexing (OFDM) as an appropriate scheme in terms of downlinks. However, the proper scheme for an uplink is the Single-Carrier Frequency Domain Multiple Access due to the peak-to-average-power-ratio (PAPR) constraint. LTE packet scheduling plays a primary role as part of RRM to improve the system’s data rate as well as supporting various QoS requirements of mobile services. The major function of the LTE packet scheduler is to assign Physical Resource Blocks (PRBs) to mobile User Equipment (UE). In our work, we formed a proposed packet scheduler algorithm. The proposed scheduler algorithm acts based on the number of UEs attached to the eNodeB. To evaluate the proposed scheduler algorithm, we assumed two different scenarios based on a number of UEs. When the number of UE is lower than the number of PRBs, the UEs with highest Channel Quality Indicator (CQI) will be assigned PRBs. Otherwise, the scheduler will assign PRBs based on a given proportional fairness metric. The eNodeB’s throughput is increased when the proposed algorithm was implemented. digital.library.unt.edu/ark:/67531/metadc490046/
Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation
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In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empirical dispersion corrections, as well as some lower-level ab initio methods. Basis set convergence is found to be relatively slow due to internal C-H…O and C-H…N contacts. Absent dispersion corrections, many DFT functionals will transpose the two lowest conformers. Dispersion corrections resolve the problem for most functionals. Double hybrids yield particularly good performance, as does MP2.5. In the second project, we propose a simple DFT-based diagnostic for nondynamical correlation effects. Aλ= (1-TAE [ΧλC]/TAE[XC])/λ where TAE is the total atomization energy, XC the “pure” DFT exchange-correlation functional, and ΧλC the corresponding hybrid with 100λ% HF-type exchange. The diagnostic is a good predictor for sensitivity of energetics to the level of theory, unlike most of the wavefunction-based diagnostics. For GGA functionals, Aλ values approaching unity indicate severe non-dynamical correlation. The diagnostic is only weakly sensitive to the basis set (beyond polarized double zeta) and can be applied to problems beyond practical reach of wavefunction ab-initio methods required for other diagnostics. digital.library.unt.edu/ark:/67531/metadc500195/
Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy
The accurate assessment of psychopathy constitutes a critical component of forensic assessments addressing offender populations. Among the core characteristics of psychopathy, the interpersonal component of deception and empathic deficits are prominently observed in offenders with psychopathic traits. Given the negative consequences of being classified as a psychopath, offenders may be likely to minimize their psychopathic traits. In particular, no research has investigated whether offenders with psychopathic traits are able to simulate empathy in an effort to mask their cognitive or affective empathy deficits (e.g., lack of remorse about offenses). The present study aims to contribute to the literature with regard to the simulation of empathy. Using a mixed between- and within-subjects design, 81 male detainees were placed into (a) a low psychopathy group, (b) a moderate psychopathy group, or (c) a high psychopathy group based on the Psychopathy Checklist – Revised. For the within-subjects component, all offenders answered empathy questionnaires under genuine and simulation conditions. Results indicate the sample possessed cognitive empathy, but did not display affective empathy under genuine instructions. Under simulation instructions, participants significantly increased their scores on several empathy measures. The implications of simulated empathy and comparisons between groups regarding simulation abilities are discussed. digital.library.unt.edu/ark:/67531/metadc283859/
The Academic Steroid: Nonmedical Use of Prescription Stimulants at a North Texas University
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The goal of this study was to determine the extent, motivations, and justifications of nonmedical prescription stimulant use among the population at a large public university in the North Texas region. Participants consisted of 526 undergraduate students enrolled at the studied university during the spring and summer 2014 semesters. The findings of the study suggest that the nonmedical use by students was higher than the findings in much of the current literature, but was within the parameters established in the literature. The primary motivation for nonmedical use was academic in nature and was justified by moderation of nonmedical use to strategic academic times. digital.library.unt.edu/ark:/67531/metadc699893/
Accelerated Corrosion Test with Operation Simulation of All-Aluminum Microchannel Heat Exchangers
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The HVAC&R industry is looking to transition from copper-aluminum heat exchangers to all-aluminum microchannel technology. The want for the transition stemmed from seeing the performance improvement of all-aluminum microchannel radiators in the automotive industry. Applications differ between the two industries; therefore, applying this technology for HVAC&R use must be validated. Research towards operating modes of an all-aluminum heat exchanger in a defined corrosive environment will provide the industry with a better understanding of heat exchanger design and heat exchanger material selection. The worth in this is preventing overdesign and producing more efficient heat exchangers. Furthermore, ASHRAE members and the corrosion community will find value in a defined corrosion system and corrosion test procedure. The information gained through past research has progressed assessment of material performance; however, the methods improperly simulate and expedite natural weathering. The most common method being used is the ASTM (American Society of Testing Materials) Sea Water Acetic Acid Test. The research discussed in this paper was focused on improving a standard corrosion system by implementing system modifications to simulate heat exchanger operation while performing a modified wet-dry cyclic test (e.g. ASTM G85 Annex 5). The goal is to produce results that are more representative of natural corrosion behavior and its forms. Current results were gathered from five of ten samples that underwent initial testing. Finally, possible improvements towards the chamber system and the test method, including the salt solution, are discussed. digital.library.unt.edu/ark:/67531/metadc849775/
An Accelerometer-based Gesture Recognition System for a Tactical Communications Application
In modern society, computers are primarily interacted with via keyboards, touch screens, voice recognition, video analysis, and many others. For certain applications, these methods may be the most efficient interface. However, there are applications that we can conceive where a more natural interface could be convenient and connect humans and computers in a more intuitive and natural way. These applications are gesture recognition systems and range from the interpretation of sign language by a computer to virtual reality control. This Thesis proposes a gesture recognition system that primarily uses accelerometers to capture gestures from a tactical communications application. A segmentation algorithm is developed based on the accelerometer energy to segment these gestures from an input sequence. Using signal processing and machine learning techniques, the segments are reduced to mathematical features and classified with support vector machines. Experimental results show that the system achieves an overall gesture recognition accuracy of 98.9%. Additional methods, such as non-gesture recognition/suppression, are also proposed and tested. digital.library.unt.edu/ark:/67531/metadc822779/
Acculturation, Acculturative Stress, and Anxiety Among Hispanic Undergraduates
First generation college students face some unique challenges in the pursuit of higher education. Aside from academic stressors, there are stressors related to social and cultural transitions which may exacerbate pre-existing emotional or psychological distress. Research suggests that acculturation influences psychological well-being and development. The current study examined the relationships between acculturation, acculturative stress, socio-economic status, and symptoms of anxiety among first-generation college students of Hispanic origin. Participants (N = 125) included those who were first in their family to attend college and were primarily female, of traditional college age, and of Mexican heritage. All measures were self-report and were completed online. Overall, this study was inconclusive as most analyses were underpowered. The present study failed to support a relationship between style of acculturation and symptoms of anxiety, although, experiencing Anglo marginality was related to high levels of acculturative stress and anxiety. Finally, regression analysis revealed that acculturative stress, age, and Anglo marginalization were significant predictors of anxiety and accounted for 31% of variance in anxiety. Implications of the present study were discussed. Further study with adequate power is highly recommended. digital.library.unt.edu/ark:/67531/metadc68072/
Acculturation and Depression in Older Mexican American Adults: the Role of Social Support
Despite socioeconomic disadvantages, less acculturated Mexican Americans tend to exhibit better mental health than their more acculturated counterparts. However, in the case of older Mexican American adults, research has demonstrated the opposite to be true (Gonzalez, Haan, & Hinton, 2001). A variable of interest potentially responsible for this difference is social support. Thus, the current study proposed to investigate the mediation and moderation effects that social support has on the relationship between acculturation and depression in older Mexican American adults age 60 or older. Data from the Health and Retirement Study (HRS) was analyzed. Results showed that the mediating effect of contact with one’s children (-.109*) and the moderating effect of total social support and contact with one’s children (-.127*; -.103*) were statistically significant in the relationship between acculturation and depression. Although these effects are small they may still hold important implications for better understanding this population. digital.library.unt.edu/ark:/67531/metadc149567/
Acculturation and Feminist Endorsement on Control of Health and Health Behaviors in Hispanic Females
Hispanic women are the fastest growing population in the United States. Thus, it is important to explore health disparities that affect this population and better understand potential causes. Several explanations have been proposed for disparities that exist including turning to cultural alternatives rather than conventional medicine, low numbers of health insurance enrollments among Hispanics, and acculturation. However, little attention has been given to explanations that take into account the unique experiences of Hispanic women. The present study explored these experiences through investigation of endorsement of feminist attitudes (e.g., gender role adherence and beliefs that men and women should be treated equally in society) and level of acculturation. Undergraduate Hispanic women (18-24 years of age, M = 20.25, SD = 1.51) at the University of North Texas completed measures including the Multidimensional Health Questionnaire, the Acculturation Rating Scale for Mexican Americans-II, and the Liberal Feminist Attitude and Ideology Scale. Although results indicate that acculturation was not significant in the sample, feminist endorsement was found to be positively correlated with health-esteem, health-efficacy, and internal-health locus of control. Limitations and recommended directions for future research are explored. digital.library.unt.edu/ark:/67531/metadc500136/
Across Borders and Barlines: Chicana/o Literature, Jazz Improvisation, and Contrapuntal Solidarity
In this study, I examine Chicana/o writings and Black and Brown musical traditions as they entwine in urban centers and inform local visions of inclusion and models of social change. By analyzing literature and music from South Texas, Southern California, and Northeastern Michigan, I detail how the social particularities of each zone inform Chicana/o cultural productions rooted in the promise of empowerment and the possibility of cross-cultural solidarity. I assert that highlighting localized variations on these themes amplifies contrapuntal solidarities specific to each region, the relationship between different, locally conceived conceptions of Chicana/o identity, and the interplay between Brown and Black aesthetic practices in urban centers near national borders. Through literary critical and ethnomusicological frameworks, I engage the rhetorical patterns that link poetry, jazz improvisation, essays, musical playlists, and corridos to illumine a web of discourses helping to establish the idiosyncratic yet complimentary cultural mores that shape localized social imaginaries in the United States. digital.library.unt.edu/ark:/67531/metadc500033/
Act Like a Punk, Sing Like a Feminist: a Longitudinal Content Analysis of Feminist Themes in Punk Rock Song Lyrics, 1970-2009
Punk rock music has long been labeled sexist as copious media-generated accounts and reports of the genre concentrate on male artists, hyper-masculine performances, and lyrics considered to be aggressive, sexist, and misogynist. However, scholars have rarely examined punk rock music longitudinally, focusing heavily on 1980s and 1990s manifestations of the genre. Furthermore, few systematic content analyses of feminist themes in punk rock song lyrics have been conducted. The present research is a longitudinal content analysis of lyrics of 600 punk rock songs released for four decades between 1970 and 2009 to examine the prevalence of and longitudinal shifts in antiestablishment themes, the prevalence of and longitudinal shifts in sexist themes relative to feminist themes, the prevalence of and longitudinal shifts in specific feminist branches, and what factors are related to feminism. Using top-rated albums retrieved from Sputnik Music’s “Best Punk Albums” charts, systematic random sampling was applied to select 50 songs for each combination of three gender types and four decades. Sexism and feminism were then operationalized to construct a coding sheet to examine relevant dimensions. While the present study found no significant patterns of longitudinal increase or decrease in feminist or sexist themes, it revealed that feminist themes were consistently high across four decades and, furthermore, indicated a phenomenon of post-modern hybridity. digital.library.unt.edu/ark:/67531/metadc801944/
Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses
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The purpose of this study is to find out that if antibiotic streptomycin decreases neuronal network activity or affects the pharmacological responses. The experiments in this study were conducted via MEA (multi-electrode array) technology which records neuronal activity from devices that have multiple small electrodes, serve as neural interfaces connecting neurons to electronic circuitry. The result of this study shows that streptomycin lowered the spike production of neuronal network, and also, sensitization was seen when neuronal network pre-exposed to streptomycin. digital.library.unt.edu/ark:/67531/metadc700026/
The Acute Hormonal Response to the Kettlebell Swing Exercise
The purpose of this investigation was to examine the acute hormonal response to a bout of kettlebell swing exercise. Ten healthy men (19-30 y, 23.6 ± 3.5 y, 174.6 ± 5.7 cm, 78.7 ± 9.9 kg) who were engaged in resistance training at least twice per week but were inexperienced with kettlebell swings participated in this study. Participants were familiarized with the kettlebell swing exercise during an initial visit. During the subsequent experimental protocol visit, participants performed 12 rounds of 30 seconds of 16-kg kettlebell swings alternated with 30 seconds of rest. Heart rate (HR) and rating of perceived exertion (RPE) were measured at the end of every round of swings. Fasted blood samples were collected pre-exercise (PRE), immediately post (IP), 15 minutes post (P15), and 30 minutes post exercise (P30) and analyzed for total testosterone (T), growth hormone (GH), cortisol, and lactate concentrations. Participants completed a total of 227 ± 23 swings (average swings per round: 19 ± 2). HR and RPE increased significantly (P < 0.05) throughout the exercise protocol. Lactate concentrations were significantly increased at all post exercise time points compared to PRE. T was significantly increased at IP compared to PRE. GH was significantly increased at IP, P15, and P30 compared to PRE. Cortisol was significantly increased at IP and P15 compared to PRE. 12 rounds of 30 seconds of kettlebell swing exercise induced an acute increase in T, GH, and cortisol concentrations in resistance trained men. Additionally, this exercise protocol induced a large increase in HR and lactate concentration. Thus, the kettlebell swing exercise might provide an effective method for simultaneous endurance and resistance training. digital.library.unt.edu/ark:/67531/metadc407736/
The Adagio of Mahler's Ninth Symphony: A Schenkerian Analysis and Examination of the Farewell Story
Mahler's Ninth Symphony, since its premier in 1912, has sparked much debate about its programmatic meaning. This thesis provides an in-depth analysis of the Adagio and an examination of the controversy of the farewell story. In the process of the analysis I have compared my findings to some of the important authors in Mahler's field such as Vera Micznik, Henry-Louis de La Grange, and Christopher Orlo Lewis. Some of the conclusions are that a closer investigation of the music is necessary and that the programmatic reading of the farewell story can be appropriate. digital.library.unt.edu/ark:/67531/metadc68028/
Adapting on the Plains: the United States Army's Evolution of Mobile Warfare in Texas, 1848-1859
The Army, despite having been vexed for a century on how to effectively fight the Plains Indians, ultimately defeated them only a decade after the Civil War. This thesis will bring to the forefront those individuals who adapted fighting techniques and ultimately achieved victories on the Texas frontier before the Civil War. The majority of these victories came as a result of mounted warfare under the direction of lower ranking officers in control of smaller forces. The tactic of fighting Indians from horseback was shown to be effective by the Rangers and later emulated by the Army. digital.library.unt.edu/ark:/67531/metadc271787/
Adaptive Advantages of Carotenoid Pigments in Alpine and Subalpine Copepod Responses to Polycyclic Aromatic Hydrocarbon Induced Phototoxicity
Alpine zooplankton are exposed to a variety of stressors in their natural environment including ultraviolet radiation. Physiological coping mechanisms such as the accumulation of photoprotective compounds provide these zooplankton protection from many of these stressors. Elevated levels of carotenoid compounds such as astaxanthin have been shown to help zooplankton survive longer when exposed to ultraviolet radiation presumably due to the strong antioxidant properties of carotenoid compounds. This antioxidant capacity is important because it may ameliorate natural and anthropogenic stressor-induced oxidative stress. While previous researchers have shown carotenoid compounds impart increased resistance to ultraviolet radiation in populations of zooplankton, little work has focused on the toxicological implications of PAH induced phototoxicity on zooplankton containing high levels of carotenoid compounds. This thesis discusses research studying the role that carotenoid compounds play in reducing PAH induced phototoxicity. By sampling different lakes at elevations ranging from 9,500' to 12,700' in the front range of the Colorado Rocky Mountains, copepod populations containing different levels of carotenoid compounds were obtained. These populations were then challenged with fluoranthene and ultraviolet radiation. Results discussed include differences in survival and levels of lipid peroxidation among populations exhibiting different levels of carotenoid compounds, and the toxicological and ecological implications of these results. digital.library.unt.edu/ark:/67531/metadc28444/
Addressing Social Elements of Wildfire: Risk, Response, and Recovery in Highland Village, TX
Representatives of the City of Highland Village expressed concern over the risk of wildfires for their community. Anthropology provides many tools for and examples of disaster assessment of preparedness, response, recovery, and mitigation. These tools combined with Geographic Information Systems (GIS) can provide a holistic, cultural ecological look at how such a disaster may take place in the city. The project's methods included a detailed survey of preparedness steps which was analyzed using SPSS and also imported into ArcGIS for spatial analysis, and semi-formal, in-depth interviews with residents of the community regarding preparedness, response, and recovery. Residents fell into a middle category of preparedness, with the majority of participants considering or implementing a few recommended preparedness steps. Interview participants expressed respect for and trust of the city and first-responders, as well as a willingness to volunteer their help during response and recovery stages. Finally the American Community Survey showed that resident socioeconomic vulnerability was considerably low, and no action needed to be taken to advocate for at-risk individuals. Overall, the City of Highland Village showed a high resiliency to disaster. A wildfire likely will not have a major impact on the community as a whole, though the city may reduce the impact even further by informing the public of their risk, clearing natural areas of dead brush, sharing preparedness and evacuation information via social media and newsletters, and planning relief stations for those who may have been impacted. digital.library.unt.edu/ark:/67531/metadc849756/
ADHD Symptomology and Overweight Among College Men
Attention deficit/hyperactivity disorder (ADHD) is a childhood disorder that often persists into adulthood. Among adults, ADHD is highly comorbid with addictive behaviors (e.g., substance abuse and dependence), and depressive disorders. Recently, an association between ADHD and obesity has been reported in the literature; emotional and binge eating may be “addictive behaviors” that contribute to weight gain in this population. The purpose of this study was to test competing models of the hypothesized link between ADHD symptomology and overweight. Specifically, in Model 1, symptoms of depression are expected to mediate the relationship between symptoms of impulsivity and inattention and emotional and binge eating which, in turn, leads to weight gain (i.e., increased BMI). In Model 2, however, the impulsive symptoms have direct relationships with emotional and binge eating in addition to being mediated by depressive symptoms. Structural equation modeling (SEM) was employed to test how the models fit the data of 790 college men. Both models fit the data well, with Model 2 being preferred because of its greater connection to theory. All paths were significant indicating that increased impulsive and inattentive symptoms predicted increased symptoms of depression that, in turn, predicted increased emotional/binge eating, which has a direct and positive relationship with increased BMI. Moreover, impulsive symptoms were also directly related to emotional/binge eating, suggesting different paths to overweight across ADHD subtypes. The findings of the current study elucidate the links between ADHD symptoms and overweight (i.e., increased BMI). digital.library.unt.edu/ark:/67531/metadc103337/
Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods
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Two-dimensional (2D) transition metal dichalcogenides (TMDs) show great potential for the future electronics, optoelectronics and energy applications. But, the studies unveiling their interactions with the host substrates are sparse and limits their practical use for real device applications. We report the facile nano-scratch method to determine the adhesion energy of the wafer scale MoS2 atomic layers attached to the SiO2/Si and sapphire substrates. The practical adhesion energy of monolayer MoS2 on the SiO2/Si substrate is 7.78 J/m2. The practical adhesion energy was found to be an increasing function of the MoS2 thickness. Unlike SiO2/Si substrates, MoS2 films grown on the sapphire possess higher bonding energy, which is attributed to the defect-free growth and less number of grain boundaries, as well as less stress and strain stored at the interface owing to the similarity of Thermal Expansion Coefficient (TEC) between MoS2 films and sapphire substrate. Furthermore, we calculated the surface free energy of 2D MoS2 by the facile contact angle measurements and Neumann model fitting. A surface free energy ~85.3 mJ/m2 in few layers thick MoS2 manifests the hydrophilic nature of 2D MoS2. The high surface energy of MoS2 helps explain the good bonding strength at MoS2/substrate interface. This simple adhesion energy and surface energy measurement methodology could further apply to other TMDs for their widespread use. digital.library.unt.edu/ark:/67531/metadc849762/
Adoptive Parenthood: an Exploratory Study of the Influence of Pre-adoption Communication Satisfaction on Post-adoption Family Adjustment and Coping
There are over a million adopted children in the United States, which makes up over 2% of the population. in spite of the fact that the majority of children are adopted into loving and caring homes, early life trauma puts them at higher risk for developing behavioral and emotional problems than non-adopted children. Due to these issues, many adoptive parents encounter post-adoption stress. This stress is often linked to minimal education regarding short- and long-term challenges associated with adoption. the adoption agency is likely the best group for addressing challenges, yet few researchers have studied adoption agency communication and adoptive parent adjustment. in this study I examined pre-adoption communication satisfaction, post-adoption adjustment (life change and parental adjustment), and coping strategies. Hypothesis 1 questioned the relationship between adoptive parents’ pre-adoption communication satisfaction with their social workers and post-adoption family adjustment; this hypothesis was supported only for problems related to home and work life adjustment. Hypothesis 2 predicted coping strategies would mediate the relationship between communication satisfaction and family adjustment. H2 was not supported for both life change and parental adjustment. Research Questions 1a and 1b inquired about the coping strategy that had an impact on life change and parental adjustment; escape-avoidance coping was most common for problems related to parental difficulty adjustment. a second research question was added post hoc; it questioned if special needs adopted children had an impact on family adjustment. Results indicated the special needs designation is related to home and work life adjustment. After discussing the theoretical and practical implications of this study, I offer limitations and directions for future research. digital.library.unt.edu/ark:/67531/metadc115154/
Adult Attachment, Acculturation and Help-seeking of Latino College Students
Based on theoretical reasoning and empirical evidence, the present study examined the unique and shared effects of attachment anxiety, attachment avoidance, and acculturation on attitudes toward seeking professional help among Latino college students. The research participants included 149 bilingual Latino college students from a large, public southwestern university. Results of a multiple regression analysis indicated that attachment avoidance was positively associated with both the recognition of need for psychological help and stigma of seeking professional help. Acculturation to American society was found to be statistically insignificant in predicting help-seeking attitudes in this sample of the population. Findings from exploratory questions suggested that Latino individuals would most likely seek help from parents, close friends, and then professionals. This study suggested that Latino individuals with high attachment avoidance acknowledge the potential benefit of professional help-seeking but distrust the process of approaching others for help. Limitations, implications, and future research directions will be discussed. digital.library.unt.edu/ark:/67531/metadc801882/
An Age-based Etic Analysis of Orthographic Variation in Computer-mediated French Discourse
This study examines orthographic variation in synchronous computer-mediated French discourse. All nontraditional variations of selected frequently occuring items are quantified in order to provide an etic (i.e., from an external perspective) analysis. The primary variable of interest is age since this study focuses on providing a comparison of chat participants in their twenties versus those in their fifties. The widespread claim is that younger people communicate using more informal and/or nontraditional forms than older people; however, the results of the present study suggest that this is not always the case. The main finding of the present study is that the twentysomethings and the fiftysomethings produce the nontraditional orthography in a similar fashion in 52.2% of the terms, and in a non-similar fashion in 47.8% of the terms. Following the presentation and discussion of the results, directions for future research are provided. digital.library.unt.edu/ark:/67531/metadc407821/
AirSniffer: A Smartphone-Based Sensor Module for Personal Micro-Climate Monitoring
Environmental factors can have a significant impact on an individual's health and well-being, and a primary characteristic of environments is air quality. Air sensing equipment is available to the public, but it is often expensive,stationary, or unusable for persons without technical expertise. The goal of this project is to develop an inexpensive and portable sensor module for public use. The system is capable of measuring temperature in Celsius and Fahrenheit, heat index, relative humidity, and carbon dioxide concentration. The sensor module, referred to as the "sniffer," consists of a printed circuit board that interconnects a carbon dioxide sensor, a temperature/humidity sensor, an Arduino microcontroller, and a Bluetooth module. The sniffer is small enough to be worn as a pendant or a belt attachment, and it is rugged enough to consistently collect and transmit data to a user's smartphone throughout their workday. The accompanying smartphone app uses Bluetooth and GPS hardware to collect data and affix samples with a time stamp and GPS coordinates. The accumulated sensor data is saved to a file on the user's phone, which is then examined on a standard computer. digital.library.unt.edu/ark:/67531/metadc849691/
Alberto Ginastera and the Guitar Chord: An Analytical Study
The guitar chord (a sonority based on the open strings of the guitar) is one of Alberto Ginastera's compositional trademarks. The use of the guitar chord expands throughout forty years, creating a common link between different compositional stages and techniques. Chapters I and II provide the historical and technical background on Ginastera's life, oeuvre and scholar research. Chapter IV explores the origins of the guitar chord and compares it to similar specific sonorities used by different composers to express extra-musical ideas. Chapter V discusses Ginastera's initial uses and modifications of the guitar chord. Chapter VI explores the use of the guitar chord as a referential sonority based on Variaciones Concertantes, Op. 23: I-II, examining vertical (subsets) and horizontal (derivation of motives) aspects. Chapter VII explores uses of trichords and hexachords derived from the guitar chord in the Sonata for Guitar Op. 47. digital.library.unt.edu/ark:/67531/metadc33152/
Alchemies
This thesis consists of a collection of poems and a critical preface. The preface is a discussion of Elizabeth Bishop's descriptive mode, as demonstrated by three of her poems: "Sandpiper," "The Monument," and "Santarém." I argue for Bishop's descriptions as creative acts, and examine the gestures that help her make the reader aware of the shaping power she exercises. digital.library.unt.edu/ark:/67531/metadc283793/
Algorithm Optimizations in Genomic Analysis Using Entropic Dissection
In recent years, the collection of genomic data has skyrocketed and databases of genomic data are growing at a faster rate than ever before. Although many computational methods have been developed to interpret these data, they tend to struggle to process the ever increasing file sizes that are being produced and fail to take advantage of the advances in multi-core processors by using parallel processing. In some instances, loss of accuracy has been a necessary trade off to allow faster computation of the data. This thesis discusses one such algorithm that has been developed and how changes were made to allow larger input file sizes and reduce the time required to achieve a result without sacrificing accuracy. An information entropy based algorithm was used as a basis to demonstrate these techniques. The algorithm dissects the distinctive patterns underlying genomic data efficiently requiring no a priori knowledge, and thus is applicable in a variety of biological research applications. This research describes how parallel processing and object-oriented programming techniques were used to process larger files in less time and achieve a more accurate result from the algorithm. Through object oriented techniques, the maximum allowable input file size was significantly increased from 200 mb to 2000 mb. Using parallel processing techniques allowed the program to finish processing data in less than half the time of the sequential version. The accuracy of the algorithm was improved by reducing data loss throughout the algorithm. Finally, adding user-friendly options enabled the program to use requests more effectively and further customize the logic used within the algorithm. digital.library.unt.edu/ark:/67531/metadc804921/
Alignment of Middle School Core TEKS with Visual Arts TEKS
This descriptive study uses a qualitative, content analysis to examine the middle school visual arts and core Texas Essential Knowledge and Skills (TEKS) to determine the potential common learning activities that can be aligned between the two. By performing an alignment of the potential common learning activities present in the middle school visual art TEKS and the middle school core TEKS, I demonstrate that there is a foundation for curriculum integration in the Texas middle school visual arts classroom. digital.library.unt.edu/ark:/67531/metadc33160/
“Almost Astronauts”: Short Stories
In this collection of short stories, I abduct experiences from my own life and take them on an imaginative journey. I experiment with elements of structure and point of view, often incorporating the magical or surreal to amplify the narrator’s internal landscape. As demonstrated in the title story, “Almost Astronauts,” these stories all deal with a sudden and sometimes destructive shift in the narrator’s perspective. digital.library.unt.edu/ark:/67531/metadc115120/
Alterations in Fatty Acid Amide Hydrolase (Faah) Transcript Levels and Activity Lead to Changes in the Abiotic Stress Susceptibility of Arabidopsis Thaliana
N-Acylethanolamines (NAEs) are a class of bioactive lipids, and FAAH is one of the enzymes responsible for degrading NAEs in both plants and animals. in plants, FAAH appears to be closely associated with ABA, a phytohormone which has long been associated with plant stress responses, since the overexpression of FAAH in Arabidopsis results in ABA hypersensitivity. Therefore, it is reasonable to speculate that alterations in FAAH transcript levels will result in altered stress responses in plants. to investigate this hypothesis experiments were carried out in which wild type (WT), FAAH-overexpressing (OE), and T-DNA insertional FAAH knockouts of Arabidopsis (faah) were grown in MS media under stress conditions. the stress conditions tested included chilling stress, heavy metal stress induced by cadmium or copper, nutrient limitations induced by low phosphorus or low nitrogen, salt stress induced with NaCl, and osmotic stress induced with mannitol. the OE plants were consistently hypersensitive to all stress conditions in relation to wild type plants. Inactive FAAH overexpressors did not have the hypersensitivity to the salt and osmotic stress of the active OE plants and were instead tolerant to these stresses. FAAH2 (faah2) knockouts and FAAH 1 and 2 double knockouts (faah 1+2) were based on some root development parameters somewhat more tolerant than WT plants, but more sensitive in terms of shoot growth. Collectively the data suggests that FAAH activity may interact with stress-responsive pathways in plants, perhaps including pathways involving ABA. digital.library.unt.edu/ark:/67531/metadc115085/
Alternative Complementation in Partially Schematic Constructions: a Quantitative Corpus-based Examination of COME to V2 and GET to V2
This paper examines two English polyverbal constructions, COME to V2 and GET to V2, as exemplified in Examples 1 and 2, respectively. (1) the senator came to know thousands of his constituents (2) Little Johnny got to eat ice cream after every little league game. Previous studies considered these types of constructions (though come and get as used here have not been sufficiently studied) as belonging to a special class of complement constructions, in which the infinitive is regarded as instantiating a separate, subordinate predication from that of the “matrix” or leftward finite verb. These constructions, however, exhibit systematic deviation from the various criteria proposed in previous research. This study uses the American National Corpus to investigate the statistical propensities of the target phenomena via lexico-syntactic (collostructional analysis) and morpho-syntactic (binary logistic regression) features, as captured through the lens of construction grammar. digital.library.unt.edu/ark:/67531/metadc115110/
Amarillo Globe-News: How Did Gene Howe and the Globe-News Help Guide Amarillo, Texas through the Dust Bowl and Great Depression?
For many years newspapers were locally owned by editors and publishers. However, today many are run by corporations from out of state. As a result, many communities have lost the personal relationship between the family owned publication and the community. Gene Howe, who served as editor, publisher and columnist of the Amarillo Globe-News from 1926 until his death in 1952, believed the community was where the focus should be and the newspaper should do all that it can to help their readers. Despite the fact that Howe was not born in Amarillo, Texas, his passion and love for the city and its inhabitants compensated for it. During the Dust Bowl and Great Depression Howe and the Globe-News helped Amarillo survive the dust and economic storms that blew through the Texas Panhandle, an area that has not been written as much as other parts of Texas. Through his “Tactless Texan” column, which served as a pulpit to the community, to the various contests and promotions the newspaper sprang up, including the creation of Mother in Law Day, Gene Howe gave the newspaper another dimension little has been studied about, the role of the editor and publisher in guiding a community through a dramatic era. Understanding Howe’s ethos can allow others to examine the roles editors and newspapers play in communities throughout the country. digital.library.unt.edu/ark:/67531/metadc799498/
An Analysis of Du cristal…à la fumée by Kaija Saariaho and Axiom Unearthed, Original Composition
Beginning in the 1970s, and aided by the advancement and an increased prevalence of computers, spectral music emerged as an important development in twentieth century music. Spectral composers, as exemplified by Gérard Grisey and Tristan Murail, took the harmonic spectra of sounds as the fundamental materials of composition. The resulting music placed an emphasis on texture and gradually evolving forms. The generation of composers immediately following the spectralists assimilated their techniques into distinct and varying styles. Finnish composer Kaija Saariaho uses spectral techniques to create an aesthetic that generates form and progression from a sound/noise axis. In her piece Du cristal…à la fumée, a number of pendulum and half-pendulum gestures build up texture and form. The accompanying original composition Axiom Unearthed employs similar pendulum gestures and uses spectral techniques to generate melody and harmony in an aesthetic divergent from traditional spectral pieces. digital.library.unt.edu/ark:/67531/metadc799510/
An Analysis of Interrater Agreement Between the Motivation Assessment Scale (MAS), Questions About Behavioral Function (QABF), and Analog Assessment Outcomes
An analysis of interrater agreement across multiple respondents on anecdotal assessments was compared with experimental functional analysis outcomes for correspondence. Experiment 1 evaluated the agreement of multiple respondents on the function of problem behavior for 22 individuals across 42 target behaviors using the Motivation Assessment Scale (MAS) and the Questions About Behavioral Function (QABF). Results showed agreement on the primary maintaining consequence for 4 or 5 of the 5 respondents in 52% (22/42) of the individual's target behaviors with the MAS and 57% (24/42) with the QABF. Experiment 2 examined whether correspondence occurred between the anecdotal assessment results and experimental functional analysis (EFA) results for 7 individuals selected from Experiment 1. Correspondence between the QABF assessment and the EFA was found for 6 of 7 participants, and 4 of the 7 showed correspondence between the EFA and the MAS. This study showed that the QABF had higher correspondence with analog assessments than the MAS thus, supporting the previous findings of Paclawskyj et al. (2001). digital.library.unt.edu/ark:/67531/metadc28477/
Analysis of Micro Enterprise Clusters in Developing Countries: A Case Study of Toluca, Mexico.
Businesses cluster to achieve agglomeration benefits. However, research in developing countries suggests that the economic environment limits small business’ propensity to benefit from agglomerations. The study examines the location, networking patterns, formal structures and owner characteristics of 1256 micro businesses from ten industries and thirteen sample areas in Toluca, Mexico. First, the thesis analyses whether clustering has a positive impact on the success rates of the surveyed enterprises, e.g. higher sales per employee. On an industry scale only Retail benefits from agglomerations economies. However, results of the neighborhood data show that specific areas benefit from urbanization economies. Overall, the study finds that businesses located within agglomerations, have higher levels of formalization, networking and professional training, hence constituting a more sophisticated base for economic development. Conclusions can be drawn for development policies and programs, arguing for a more differentiated approach of small business development depending on business location and cluster characteristics. digital.library.unt.edu/ark:/67531/metadc84200/
Analysis of Sources Affecting Ambient Particulate Matter in Brownsville, Texas
Texas is the second largest state in U.S.A. based on geographical area, population and the economy. It is home to several large coastal urban areas with major industries and infrastructure supporting the fossil-fuel based energy sector. Most of the major cities on the state have been impacted by significant air pollution events over the past decade. Studies conducted in the southern coastal region of TX have identified long range transport as a major contributor of particulate matter (PM) pollution along with local emissions. Biomass burns, secondary sulfates and diesel emissions sources are comprise as the dominant mass of PM2.5 have been noted to be formed by the long range transport biomass from Central America. Thus, the primary objective of this study was to identify and quantify local as well as regional sources contributing to the PM pollution in the coastal area of Brownsville located along the Gulf of Mexico. Source apportionment techniques such as principal component analysis (PCA) and positive matrix factorization (PMF) were employed on the air quality monitoring data to identify and quantify local and regional sources affecting this coastal region. As a supplement to the PMF and PCA, conditional probability function (CPF) analysis and potential source contribution function (PSCF) analysis were employed to characterize the meteorological influences for PM events. PCA identified an optimal solution of 6 sources affecting the coastal area of Brownsville, while PMF resolved 8 sources for the same area. Biomass comingled with sea salt was identified to be the dominant contributor from the PCA analysis with 30.2% of the apportioned PM mass in Brownsville, meanwhile PMF account secondary sulfates I & II with 27.6%. the other common sources identified included, biomass burning, crustal dust, secondary sulfate, oil combustion, mobile sources and miscellaneous traffic sources. digital.library.unt.edu/ark:/67531/metadc115069/
An Analysis of the 4:2:1 Documentary
As a Chinese filmmaker, I feel obligated to reveal a true story about Chinese international students. Through my subjects and my stories, I am planning to express the messages that both adapting to a new culture and paying the financial cost of a foreign education have never been simple, but we will never give up our dreams. digital.library.unt.edu/ark:/67531/metadc500078/
An Analysis of the Correspondence Between the Measures Collected by an Autism Treatment Center and its Stated Mission Goals
This study was a program evaluation for an autism treatment center for the period of April 2008 through August 2011. the study extended previous evaluations of the autism treatment center. the purpose of this evaluation was to determine the degree to which the center’s measures corresponded with its stated mission goals. a number of data sources were reviewed including client records of demographic and outcome information. Findings suggest the center maintained records that allow for the evaluation of most of its mission’s goals. There were, however, difficulties with data collection, storage, and retrieval. the present program evaluation found that missing information and lack of follow-up information hindered efforts toward mission evaluation. digital.library.unt.edu/ark:/67531/metadc115107/
An Analysis of the Value-altering Effect of Motivating Operations
Motivating operations (MOs) may affect behavior in two ways; A) an MO momentarily alters the frequency of behavior for which a particular consequence has served as reinforcement (evocative-effect) and B) an MO momentarily alters the behavioral effects of the relevant consequence (value-altering effect). Many studies have empirically demonstrated the evocative function of MOs, however, few if any studies have attempted to systematically manipulate and measure the value-altering effect. The focus of this study was to investigate the value-altering effect by measuring choice and response allocation across two alternative tasks. Participants were two female girls diagnosed with autism. During conditioning sessions, experimenters created a history for the children in which clicking on a moving square on a computer monitor produced a small piece of edible. Prior to some conditions, the participants were allowed 5 min of free-access to the edibles, and in other sessions, access to edibles prior to session was restricted. During these sessions, the square was either red or blue depending on the condition type (pre-access or restricted-access). During probe sessions, both colored squares were concurrently available and participants were allowed to allocate their responding to whichever square they chose. One participant preferred the square associated with restricted-access, which may support the notion of the value-altering effect. Difficulties during conditioning sessions interfered with the ability to run sufficient probes with the other participant to evaluate a value-altering effect. Results suggest that the use of these procedures may be useful to differentiate evocative and function-altering effects of MOs. digital.library.unt.edu/ark:/67531/metadc500100/
An Analysis of UNT Commuting Patterns
Academic institutions have recently organized to address their campus' greenhouse gas emissions. Along those lines, the University of North Texas (UNT) pledged to minimize the campus' environmental impact, and conducted a transportation survey in May 2009. The analyses confirm that commuting to campus was the second highest source (29%) of UNT's greenhouse gas emissions, following purchased electricity (48%). Students, faculty and staff drive over 89 million miles per year, 84% of which comes from students. Forty&#8208;two percent of student driving trips originate in the primary and secondary core areas surrounding Denton, which are partially served by buses. However, because these core areas are in close proximity to the campus, they contribute only 8% of the total student driving distance. Beyond the Denton core, the inner periphery of Denton County contributes another 22% of driving mileage. Students living in the outer periphery (outside Denton County) contribute the remaining 70% of total driving distance, and carpooling is currently their only alternative. digital.library.unt.edu/ark:/67531/metadc28489/
Analytical Model for Lateral Deflection in Cold-formed Steel Framed Shear Walls with Steel Sheathing
An analytical model for lateral deflection in cold-formed steel shear walls sheathed with steel is developed in this research. The model is based on the four factors: fastener displacement, steel sheet deformation, and hold-down deformation, which are from the effective strip concept and a complexity factor, which accounts for the additional influential factors not considered in the previous three terms. The model uses design equations based on the actual material and mechanical properties of the shear wall. Furthermore, the model accounts for aggressive and conservative designers by predicting deflection at different shear strength degrees. digital.library.unt.edu/ark:/67531/metadc700013/
Analytical Model of Cold-formed Steel Framed Shear Wall with Steel Sheet and Wood-based Sheathing
The cold-formed steel framed shear walls with steel sheets and wood-based sheathing are both code approved lateral force resisting system in light-framed construction. In the United States, the current design approach for cold-formed steel shear walls is capacity-based and developed from full-scale tests. The available design provisions provide nominal shear strength for only limited wall configurations. This research focused on the development of analytical models of cold-formed steel framed shear walls with steel sheet and wood-based sheathing to predict the nominal shear strength of the walls at their ultimate capacity level. Effective strip model was developed to predict the nominal shear strength of cold-formed steel framed steel sheet shear walls. The proposed design approach is based on a tension field action of the sheathing, shear capacity of sheathing-to-framing fastener connections, fastener spacing, wall aspect ratio, and material properties. A total of 142 full scale test data was used to verify the proposed design method and the supporting design equations. The proposed design approach shows consistent agreement with the test results and the AISI published nominal strength values. Simplified nominal strength model was developed to predict the nominal shear strength of cold-formed steel framed wood-based panel shear walls. The nominal shear strength is determined based on the shear capacity of individual sheathing-to-framing connections, wall height, and locations of sheathing-to-framing fasteners. The proposed design approach shows a good agreement with 179 full scale shear wall test data. This analytical method requires some efforts in testing of sheathing-to-framing connections to determine their ultimate shear capacity. However, if appropriate sheathing-to-framing connection capacities are provided, the proposed design method provides designers with an analytical tool to determine the nominal strength of the shear walls without conducting full-scale tests. digital.library.unt.edu/ark:/67531/metadc271920/
Analyzing Contingencies of Behavioral and Cultural Selection
A choice paradigm was used to evaluate allocation of interlocking behavior of two groups of two participants between responses having operant consequences only and responses having cultural consequences. In a discrete trial BABABAB design, each participant could select one of three options, which delivered either 3 or 5 points. In B (cultural consequence) conditions, two of the options had additional effects: the 3-point option also added 3 points to the other participant's earnings, and one of the 5-point options also subtracted 5 points from the other participant's earnings. The third option was unchanged in both conditions and delivered 5 points to the participant who selected it. Results indicated that participants in both groups initially frequently produced response combinations that earned 8 points for one or the other individual (and 0 or 3 points for the other), but allocation of responding increasingly changed to combinations that produced 6 points for each individual. This shift in performances away from maximum individual reinforcement towards maximum group reinforcement indicates cultural contingencies did not act in concert with operant contingencies, suggesting they are different mechanisms of selection. digital.library.unt.edu/ark:/67531/metadc30471/
Anatomical and Morphological Responses of Cardiospermum Halicacabum L. (Balloon Vine), to Four Levels of Water Availability
C. halicacabum (Sapindaceae) is an invasive plant that is considered a nuisance species in Texas riparian environments. Little is known of the tolerance of C. halicacabum to flooding and drought; however, this information may provide insight into the characteristics that contribute to C. halicacabum purported invasiveness. C. halicacabum seedlings (n = 92) were exposed to one of four levels of water availability (flooded, saturated, intermediate and dry) over six weeks under greenhouse conditions. Plant performance was affected by water availability; however, there was no effect on survivorship. Flooded and saturated plants exhibited morphological adaptations; producing adventitious roots, hypertrophy, and aerenchyma tissue. Morphological measures, anatomical responses, and patterns of biomass allocation all indicate that C. halicacabum is able to survive periodic inundation, perform in saturation, and establish and thrive on the drier end of a moisture gradient. digital.library.unt.edu/ark:/67531/metadc67974/
Anchor Nodes Placement for Effective Passive Localization
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Wireless sensor networks are composed of sensor nodes, which can monitor an environment and observe events of interest. These networks are applied in various fields including but not limited to environmental, industrial and habitat monitoring. In many applications, the exact location of the sensor nodes is unknown after deployment. Localization is a process used to find sensor node's positional coordinates, which is vital information. The localization is generally assisted by anchor nodes that are also sensor nodes but with known locations. Anchor nodes generally are expensive and need to be optimally placed for effective localization. Passive localization is one of the localization techniques where the sensor nodes silently listen to the global events like thunder sounds, seismic waves, lighting, etc. According to previous studies, the ideal location to place anchor nodes was on the perimeter of the sensor network. This may not be the case in passive localization, since the function of anchor nodes here is different than the anchor nodes used in other localization systems. I do extensive studies on positioning anchor nodes for effective localization. Several simulations are run in dense and sparse networks for proper positioning of anchor nodes. I show that, for effective passive localization, the optimal placement of the anchor nodes is at the center of the network in such a way that no three anchor nodes share linearity. The more the non-linearity, the better the localization. The localization for our network design proves better when I place anchor nodes at right angles. digital.library.unt.edu/ark:/67531/metadc33132/
Anger, Forgiveness and Mindfulness: Correlates of Perceived Stress in an Lgb Sample
A sexual minority is someone who identifies as lesbian, gay or bisexual (LGB). According to the Minority Stress Model (Meyer, 2003), sexual minorities encounter significant levels of stress due to their minority group status, thus they are more likely to experience perceived stress. Our cross-sectional, correlational study aimed to explore the relationships between forgiveness, mindfulness and anger and how they are related to perceived stress in a convenience sample of ethnically diverse LGB adults. We hypothesized that: 1) anger is positively associated with perceived stress; 2) forgiveness is negatively associated with perceived stress; 3) mindfulness is negatively associated with perceived stress; and 4) anger, forgiveness and mindfulness account for a significant proportion of the variance in perceived stress. 5) The relationship between anger and perceived stress is moderated by forgiveness. 6) The relationship between anger and perceived stress is moderated by mindfulness. Among LGB adults, the extant literature does not address these four variables in conjunction and the relationships between anger, forgiveness, mindfulness and stress has yet to be explored. Various statistical analyses were conducted, including a hierarchical linear regression to test our model. We found that our overall model accounted for 36% of the total variance in perceived stress (F(5, 142) = 17.31, p <.01) with anger (β = .31, t = 3.55, p = .001) and forgiveness (β = -.21, t = -2.56, p < .05) as the significant predictors. Contrary to prediction, forgiveness and mindfulness did not moderate the relationship between anger and perceived stress in our LGB sample. Limitations, strengths, future research and implications are discussed. digital.library.unt.edu/ark:/67531/metadc822763/
“The Angular Degrees of Freedom” and Other Stories
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The preface, " Performing Brain Surgery: The Problematic Nature of Endings in Short Fiction," deals with the many and varied difficulties short story writers encounter when attempting to craft endings. Beginning with Raymond Carver and Flannery O’Connor and moving to my own work, I discuss some of the obscure criteria used to designate a successful ending, as well as the more concrete idea of the ending as a unifying element. Five short stories make up the remainder of this thesis: "In-between Girls," "Crocodile Man," "Surprising Things, Sometimes Amusing," "Good Jewelry," and "The Angular Degrees of Freedom." digital.library.unt.edu/ark:/67531/metadc700030/
Anisotropic Nature of Radially Strained Metal Tubes
Metal pipes are sometimes swaged by a metal cone to enlarge them, which increases the strain in the material. The amount of strain is important because it affects the burst and collapse strength. Burst strength is the amount of internal pressure that a pipe can withstand before failure, while collapse strength is the amount of external pressure that a pipe can withstand before failure. If the burst or collapse strengths are exceeded, the pipe may fracture, causing critical failure. Such an event could cost the owners and their customers millions of dollars in clean up, repair, and lost time, in addition to the potential environmental damage. Therefore, a reliable way of estimating the burst and collapse strength of strained pipe is desired and valuable. The sponsor currently rates strained pipes using the properties of raw steel, because those properties are easily measured (for example, yield strength). In the past, the engineers assumed that the metal would be work-hardened when swaged, so that yield strength would increase. However, swaging introduces anisotropic strain, which may decrease the yield strength. This study measured the yield strength of strained material in the transverse and axial direction and compared them to raw material, to determine the amount of anisotropy. This information will be used to more accurately determine burst and collapse ratings for strained pipes. More accurate ratings mean safer products, which will minimize risk for the sponsor’s customers. Since the strained metal has a higher yield strength than the raw material, using the raw yield strength to calculate burst and collapse ratings is a conservative method. The metal has even higher yield strength after strain aging, which indicates that the stresses are relieved. Even with the 12% anisotropy in the strained and 9% anisotropy in the strain aged specimens, the raw yield strengths are lower and therefore more conservative. I recommend that the sponsor continue using the raw yield strength to calculate these ratings. I set out to characterize the anisotropic nature of swaged metal. As expected, the tensile tests showed a difference between the axial and transverse tensile strength. The correlation was 12% difference in yield strength in the axial and transverse directions for strained material and 9% in strained and aged material. This means that the strength of the metal in the hoop (transverse) direction is approximately 10% stronger than in the axial direction, because the metal was work hardened during the swaging process. Therefore, the metal is more likely to fail in axial tension than in burst or collapse. I presented the findings from the microstructure examination, standard tensile tests, and SEM data. All of this data supported the findings of the mini-tensile tests. This information will help engineers set burst and collapse ratings and allow material scientists to predict the anisotropic characteristics of swaged steel tubes. digital.library.unt.edu/ark:/67531/metadc822747/
Antón Arrufat’s “Los Siete Contra Tebas”: Political Allegory and Anthropological Concepts As Vehicles to Portray Theatrical and Social Conflict
This thesis (i) presents a critical analysis of the political allegory and dramatic elements employed by Antón Arrufat in Los siete contra Tebas in order to comment upon the conflict in Cuban society during and immediately after the Cuban revolution; and (ii) further analyzes that conflict using an anthropological approach in order to establish partial reintegration as an additional final phase in the rites of passage journey. digital.library.unt.edu/ark:/67531/metadc699886/
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