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British-Style Brass Bands in U.S. Colleges and Universities

Description: Since the 1980s, British-style brass bands - community ensembles modeled after the all-brass and percussion bands of Great Britain - have enjoyed a modest regeneration in the United States. During this same period, as many as 23 colleges and universities in the U.S. have founded their own curricular or extra-curricular brass band. The purpose of this research study was: to discover which schools sponsor a brass band currently; to discover which schools formerly sponsored a brass band but have since discontinued it; to describe the operational practices of collegiate brass bands in the U.S.; and to determine what collegiate brass band conductors perceive to be the challenges and benefits of brass band in the curriculum. Data for the study were collected between February, 2015 and February, 2016 using four custom survey instruments distributed to conductors of college and university brass bands. The results showed that 11 American collegiate institutions were sponsoring a brass band during the period of data collection. Additional findings included descriptions of the operations of collegiate brass bands, such as availability of credit, rehearsal time, and instrumentation. Results also included the conductors' reported perceptions that both challenges and benefits are inherent in student brass band participation, and that brass band is a positive experience for students. An additional 3 community-based brass bands, not sponsored by but located near a college or university, were found to include collegiate students among their player personnel. A total of 9 schools formerly sponsoring brass bands were found to have discontinued their program. A repertoire analysis of 733 titles of compositions performed by both active and formerly active brass bands revealed that bands performed original works for brass band nearly as often as transcribed or arranged works.
Date: December 2016
Creator: Taylor, Mark Amdahl

Building an Understanding of International Service Learning in Librarianship

Description: From the very beginning, library education has been a mixture of theory and practice. Dewey required apprenticeships to be part of the first library school at the University of Chicago as a method to indoctrinate new professional. Today, acculturation is incorporated into the professional education through a large variety of experiential learning techniques, including internships, practicum, field work, and service learning projects, all of which are designed to develop some level of professional skills within an information organization. But, what is done for understanding library culture? It is said that one cannot truly recognize the extent of one's own cultural assumptions, until they have experienced another. This study followed a group of LIS graduate students that took that next step – going to Russia. By employing a critical hermeneutic methodology, this study sought to understand what value students gain by from working on an assessment project in an international school library. Using a horizon analysis, the researcher established the worldview of participants prior to their departure, analyzed their experience through post-experience interviews, and constructed an understanding of value. Among other concepts, the researcher looked specifically to see whether "library cultural competency", understanding library culture in global context, was developed through working on a service learning project within an international school library. This dissertation provides feedback for the program leaders and ideas for future research.
Date: December 2016
Creator: Walczyk, Christine

Can Observing Behavior Predict Performance in Conditional Discriminations?

Description: Prompts are implemented often in training procedures, to include conditional discriminations, and this can lead to prompt dependency. The current study extends a prior study that suggested that the effectiveness of supplementary visual stimuli displaying the sample and comparison was dependent on the timing in relation to the selection task, presented as a prompt or feedback, in a match-to-sample procedure. The current research examines if the differences in that effectiveness were due to differences in observing behavior in those two conditions. Measures of observing behavior were determined by making access to the individual visual stimuli contingent on clicking on the visual stimulus and keeping the cursor located on the stimulus. Participants viewed the sample comparison much less than the comparison stimulus in both the prompt and feedback conditions. Latency to select the comparison stimulus was much shorter for the prompt condition suggesting that the participants might have interacted differently with the selection task in the two conditions.
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Date: December 2016
Creator: Marchini, Kevin Julian

Cardiovascular Fetal Programming in Quail (Colinus virginianus), An Avian Comparative Model

Description: The consequences of early embryonic insults and how they affect subsequent life reflects the emerging concept of "fetal programming". The aim of this project is to study the effects of embryonic insults as they subsequently manifest themselves in adults, with emphasis on the heart and vasculature. My experiments establish that fetal programming operates on the bobwhite quail inducing similar changes as those observed in mammalians and other birds. The quail's fast development provides reliable data in a short period of time than other avian models (e.g. domestic chicken). Data on quail showed a correlation between egg mass and hatchling mass; where small eggs produce small hatchlings but a high mortality made it impractical as a stressor for this study. Hypoxia was used as a stressor during embryonic incubation, where it induced a low hatching weight in quail that was not observable in adult birds. Morphological measurements demonstrated an increased ventricular collagen content and reduced ventricular lumen in birds in adults incubated in hypoxia consistent with hypertension. The hematological analyzes showed few differences indicating organ remodeling instead of hematopoietic compensation. The assessment of vascular reactivity pointed out an impaired endothelium dependent relaxation commonly associated to hypertension in birds and mammals. Fetal programming could be a widespread response to an adverse prenatal environment in endotherms and the resulting data from this work contributes to our understanding of fetal programming in vertebrates and its long term consequences.
Date: December 2016
Creator: Flores Santin, Josele

The Castle/Nikki Heat Phenomenon: A Detailed Examination of Female Representation in Entertainment Media

Description: As entertainment reflects a culture's ideology, it is important for researchers to study its messages and subsequently its potential meanings. Entertainment has the power to inform and persuade, creating models for behavior with which the public interacts. The entertainment texts for the purpose of this study are the Castle television series and the Nikki Heat novels. Together, they create a unique multi-layer fictional world. By using postmodern, feminist, communication, and entertainment theories, the results of this study provide a tightly focused lens which views a narrow aspect of entertainment media. Each text was thoroughly examined using textual analysis, Feminist Poststructuralist Discourse Analysis, and conversation analysis. Contrary to expectations, the results indicated that the Castle and Nikki Heat texts support hegemonic ideology, particularly through the use of exaggerated stereotypes, strict gender roles, imagery, and narrative choices that help perpetuate rape culture. The discussion outlines how these results can be interpreted through the dominant messages presented in the texts. This research is intended to serve as a foundation for future research regarding entertainment media.
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Date: December 2016
Creator: Skinner, Katharine Virginia

Characterization of Aprotic Solutes and Solvents using Abraham Model Correlations

Description: Experimental data were obtained for the computation of mole fraction solubilities of three dichloronitrobenzenes in organic solvents at 25oC, and solubility ratios were obtained from this data. Abraham model equations were developed for solutes in tributyl phosphate that describe experimental values to within 0.15 log units, and correlations were made to describe solute partitioning in systems that contain either "wet" or "dry" tributyl phosphate. Abraham model correlations have also been developed for solute transfer into anhydrous diisopropyl ether, and these correlations fit in well with those for other ethers. Abraham correlations for the solvation of enthalpy have been derived from experimental and literature data for mesitylene, p-xylene, chlorobenzene, and 1,2-dichlorobenzene at 298.15 K. In addition, the enthalpy contribution of hydrogen bonding between these solutes and acidic solvents were predicted by these correlations and were in agreement with an established method. Residual plots corresponding to Abraham models developed in all of these studies were analyzed for trends in error between experimental and calculated values.
Date: December 2016
Creator: Brumfield, Michela Lynne

Chemical and Electronic Structure of Aromatic/Carborane Composite Films by PECVD for Neutron Detection

Description: Boron carbide-aromatic composites, formed by plasma-enhanced co-deposition of carboranes and aromatic precursors, present enhanced electron-hole separation as neutron detector. This is achieved by aromatic coordination to the carborane icosahedra and results in improved neutron detection efficiency. Photoemission (XPS) and FTIR suggest that chemical bonding between B atoms in icosahedra and aromatic contents with preservation of π system during plasma process. XPS, UPS, density functional theory (DFT) calculations, and variable angle spectroscopic ellipsometery (VASE) demonstrate that for orthocarborane/pyridine and orthocarborane/aniline films, states near the valence band maximum are aromatic in character, while states near the conduction band minimum include those of either carborane or aromatic character. Thus, excitation across the band gap results in electrons and holes on carboranes and aromatics, respectively. Further such aromatic-carborane interaction dramatically shrinks the indirect band gap from 3 eV (PECVD orthocarborane) to ~ 1.6 eV (PECVD orthocarborane/pyridine) to ~1.0 eV (PECVD orthocarborane/aniline), with little variation in such properties with aromatic/orthocarborane stoichiometry. The narrowed band gap indicate the potential for greatly enhanced charge generation relative to PECVD orthocarborane films, as confirmed by zero-bias neutron voltaic studies. The results indicate that the enhanced electron-hole separation and band gap narrowing observed for aromatic/orthocarborane films relative to PECVD orthocarborane, has significant potential for a range of applications, including neutron detection, photovoltaics, and photocatalysis. Acknowledgements: This work was supported by the Defense Threat Reduction Agency (Grant No.HDTRA1-14-1-0041). James Hilfiker is also gratefully acknowledged for stimulating discussions.
Date: December 2016
Creator: Dong, Bin

Clinical Symptoms and Signs Related to Voice Disorders among Collegiate-Level Singers: A Retrospective Study

Description: The objectives of this research were to (1) characterize the demographics and vocal health history of collegiate-level singers, particularly those with a voice disorder and (2) describe and compare self-reported symptoms of singers across diagnostic categories of vocal fold disorders. Clinical reports of 56 collegiate-level singers (15 male and 41 female) who visited the Voice Diagnostic Clinic at the University of North Texas for voice evaluations between 2010 and 2015 were reviewed. Information was extracted from clinical records including demographic data, vocal health history, self-reported voice-related symptoms, and voice diagnosis confirmed by strobolaryngoscopic examinations and phonatory function testing. Diagnoses of voice disorders were grouped under three categories: normal (i.e., no perceptible pathology), benign lesions and irritation/inflammation. Seven singers were diagnosed as normal, 27 (51.8%) with benign lesions, and 22 (39.3%) with irritation/inflammation. All singers diagnosed as normal were females. Female singers have twice as many benign lesions as irritation/inflammation whereas males presented the opposite pattern. Nodules, polyps, cysts and irritation/inflammation were the most common voice disorders. Singers with allergies and a past history of voice problems demonstrated a higher incidence of voice disorders. The top five self-reported vocal symptoms were worse voice in the morning (50%), pain in throat (46.4%), voice worse with prolonged use (44.6%), vocal fatigue (42.9%), and breathiness (41.1%). Self-reported symptoms are not a reliable screening tool to determine presence or absence of vocal pathology. Voice teachers must be familiar with the singing and speaking voice of each student, so as to perceive early onset of vocal attrition symptoms and encourage the student in seeking medical attention.
Date: December 2016
Creator: Mohr, Caitlin

Clocks and Mirrors

Description: The essays featured in this collection highlight the gaps, as well as parallels, between mental illness and the human condition. In "Appearances," the narrator struggles with her own visual identity especially after reflecting on her Mom's own lengthy history with the mirror. In "Migrations," the lyrical voice of the narrator carries the reader through the typical day of a clinically depressed female character. Lastly, "Attempting the Fall," addresses the issues society has with mental illness by following the narrator from her suicide attempt to the mental ward.
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Date: December 2016
Creator: Thies, Jaclyn Michele

Cognitive Engagement in Later Life: Descriptive and Explanatory Findings

Description: Findings on the relationship between engagement in lifestyle and cognitive functioning are not consistent; some authors report that engagement in lifestyle predicts an individual's cognitive functioning; while other report that an individual's cognitive functioning predicts the type and level of engagement an individual participates in. The current study will use longitudinal data (N = 235) to investigate the bidirectional relationship between engagement (engaged lifestyle activities) and cognition (crystallized & fluid intelligence). Despite inconsistent findings it is proposed that cognitive functioning may be better understood when examining how stimulation of activity, need for cognition, and openness to experience affect engagement in an active lifestyle. As such the current study will investigate if stimulation of activity, need for cognition, and openness to experience moderate the relationship between engaged lifestyles and cognitive functioning. The results, limitations and implications are discussed.
Date: December 2016
Creator: Abdullah, Bashir

Commissioning Music for Trombone and Percussion: A Collaboration Between Composer and Performer with an Accompanying Survey of Trombone and Percussion Repertoire

Description: The repertoire for trombone and percussion has grown in popularity since the later 1980s. There are currently more than 110 pieces written for the ensemble. This project follows the commissioning and collaboration of Dr. Blake Tyson, Professor of Percussion at the University of Central Arkansas and well known percussion composer, in the creation of a new piece for trombone and percussion. The project also created a survey of works for trombone and percussion duet that includes 32 works. The survey includes details such as specific percussion instrumentation range, tessitura, grade level, publisher, and a description of each piece.
Date: December 2016
Creator: Cook, Justin Hastings

A Comparative Analysis of Digital and Paper Restaurant Menus Based on Customer Perception and Nutritional Labeling

Description: The restaurant industry is a highly customer-driven field. Therefore, it is imperative that restaurateurs consider customer expectations with regard to restaurant menus. The purpose of this experimental study is to examine the effects of menu format (i.e., paper or digital) and amount of nutritional information (i.e., extensive, brief, or none) on customer perceptions of the effectiveness, perceived ease of use, and information quality of the menu. Furthermore, this research intends to test the effect of these three menu attributes on the outcomes of value and satisfaction in order to assess the competitive advantage of one format over the other. The Cognitive Appraisal and Information Processing Theories provide structure to the proposed conceptual framework and give credence to the findings. This study also fills gaps in the present research by not only ameliorating weaknesses of extant studies, but also by examining several different aspects of restaurant menus simultaneously within a single study.
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Date: December 2016
Creator: Moody, Bailey

Contributions to Descriptive Set Theory

Description: Assume AD+V=L(R). In the first chapter, let W^1_1 denote the club measure on \omega_1. We analyze the embedding j_{W^1_1}\restr HOD from the point of view of inner model theory. We use our analysis to answer a question of Jackson-Ketchersid about codes for ordinals less than \omega_\omega. In the second chapter, we provide an indiscernibles analysis for models of the form L[T_n,x]. We use our analysis to provide new proofs of the strong partition property on \delta^1_{2n+1}
Date: December 2016
Creator: Dance, Cody

Coping Strategy as Mediator between Parental Attachment and the Parent-Child Relationship

Description: Previous research has shown that adult attachment anxiety and attachment avoidance are associated with both coping strategy use and the parent-child relationship. Additionally, research has shown that coping strategy is associated with aspects of the parent-child relationship. The current study aimed to further examine associations between parental romantic attachment, coping strategy use, and the parent-child relationship. It was hypothesized that coping strategy use would mediate the relationship between parental romantic attachment and aspects of the parent-child relationship. Participants included 86 heterosexual couples (N = 176 parents) from the Family and Kid Connection project archival dataset. Instruments included a demographic questionnaire, the Experiences in Close Relationships Scale, a brief measure of coping, and the Attachment and Relational Frustration Subscales of the Parenting Relationship Questionnaire. An actor-partner independence model was proposed and tested via multilevel modeling. Higher levels of parental attachment anxiety predicted poorer parent-child relationships. Father's attachment avoidance also predicted poorer father-child relationships. Higher levels of both parental attachment dimensions predicted greater use of avoidant emotional coping. Finally, greater use of avoidant emotional coping predicted poorer parent-child relationships. Results partially supported proposed mediational hypotheses. Two mediational paths were supported by results: an actor-actor path in which fathers' avoidant emotional coping mediated the association between fathers' romantic attachment avoidance and father-child attachment, and an actor-actor path in which mothers' avoidant emotional coping mediated the association between mothers' romantic attachment anxiety and mother-child attachment.
Date: December 2016
Creator: Baxter, Lauren N

Costly Ignorance: The Denial of Relevance by Job Seekers: A Case Study in Saudi Arabia

Description: Job centers aid businesses seeking qualified employees and assist job seekers to select and contact employment and training services. Job seekers are also offered the opportunity to assess their skills, abilities, qualifications, and readiness. Furthermore, job centers ensure that job seekers are complying with requirements that they must meet to benefit from job assistance programs such as unemployment insurance. Yet, claimants often procrastinate and/or suspend their job search efforts even though such actions can make them lose their free time and entitlements, and more importantly they may lose the opportunity to take advantage of free information, services, training, and financial assistance for getting a job to which they have already made a claim. The current work looks to Chatman's "small worlds" work, Johnson's comprehensive model of information seeking, and Wilson's "costly ignorance" construct for contributions to understanding such behavior. Identification of a particular trait or set of traits of job seekers during periods of unemployment will inform a new Job Seeking Activities Model (JSAM). This study purposely examines job seeker information behavior and the factors which influence job seekers' behavior, in particular, family tangible support as a social norm effect. A mixed method, using questionnaires for job hunting completers and non-completers and interviews for experts, was employed for data collection. Quantitative data analysis was conducted to provide the Cronbach α coefficient, Pearson's product moment correlation, an independent-sample t-test, effect size, and binary Logit regression. The qualitative data generated from the interview transcript for each section of the themes and subthemes were color coded. Finally, simultaneous triangulation was carried out to confirm or contradict the results from each method. The findings show that social norms, particularly uncontrolled social support provided by their families, are more likely to make job seekers ignore the relevant information about jobs available to them in favor ...
Date: December 2016
Creator: Alahmad, Badr Suleman

Creating a Verbal Community for Describing Emotional Responses within a Contingency Lens: The Effects of a Brief Training Workshop

Description: Observing emotional responses is recognized as a valuable clinical skill in a variety of professions, including applied behavior analysis. Emotional responses can flag possible contingencies thereby guiding a behavior analyst to better select valid measures, goals, and procedures. Additionally, emotional responses can be goals in and of themselves. The purpose of the present study was to evaluate the effects of a workshop on the observation and description of emotional responses by behavior analysts-in-training. The procedures included instructions, modeling, practice, discussion and feedback. The workshop included a blend of trainer presentation and interteaching strategies. The effects of the workshop were evaluated using a single-subject A-B design with multiple probe measures across four students. During probe assessments participants watched short video clips of family interactions and wrote a descriptive narrative in response to several questions. This created a permanent record for quantitative evaluation and analysis. The study resulted in an increase in the number of descriptions of emotional responses among all participants. The participants also increased responses tying the emotional response to external environmental events more often in the post-workshop assessment than the pre-workshop assessment. Results are discussed within the context of training applied behavior analysts, the analysis of verbal behavior, and the role of emotions in clinical practice.
Date: December 2016
Creator: Garden, Regan E.

Cyclic Polarization of AA 3102 in Corrosive Electrolytes Containing Sodium Chloride and Ammonium Sulfate

Description: Corrosion of all aluminum microchannel heat exchangers present a challenge in automotive and heating, ventilation, and air conditioning (HVAC) industries. Reproducibility of Salt Water Acetic Acid Test (SWAAT) has been questioned and a need to new corrosion tests with better reproducibility has risen. Cyclic polarization, that is an electrochemical test, was explored for its suitability for the assessment of AA 3102 tube material that is currently a popular aluminum alloy used in manufacturing of heat exchanger. Corrosive electrolytes containing 3.5 % sodium chloride with 0.5 % ammonium sulfate (high chloride) or 0.5 % sodium chloride with 3.5 % ammonium sulfate (high sulfate) at their pH or acidic (pH=4) were used to measure corrosion potential (Ecorr), protection potential (Epp), pitting potential (Epit), Tafel constants (βa and βc), corrosion rate (mpy). Corrosive electrolyte used in SWAAT test (4.2% Sea Salt at pH 2.9) was also used to compare corrosion resistance of AA 3102 in SWAAT electrolyte compared to the other electrolytes used in this research. Scanning electron microscopy (SEM) was used to observe and document sample surface corrosion damage after each electrochemical test on all samples. Results of the cyclic polarization tests indicated that SWAAT electrolytes was the most aggressive electrolyte resulting in highest corrosion rates compared to all other electrolytes used in this investigation. SEM results indicated AA 3102 alloy exhibited higher pitting tendency in electrolytes with high sodium chloride whereas high sulfate electrolytes cause appearance of uniform corrosion surface damage on this alloy. Both high sulfate and SWAAT electrolytes showed intergranular corrosion but high chloride electrolyte showed severe pitting of AA 3102. Mohammad Navid Dorreyatim- Cyclic Polarization of AA 3102 in Corrosive Electrolytes Containing Sodium Chloride and Ammonium Sulfate. Master of Science (Mechanical and Energy Engineering), December 2016, 98 pp., references, 31 titles.
Date: December 2016
Creator: Dorreyatim, Mohammad

A Decomposition of the Group Algebra of a Hyperoctahedral Group

Description: The descent algebra of a Coxeter group is a subalgebra of the group algebra with interesting representation theoretic properties. For instance, the natural map from the descent algebra of the symmetric group to the character ring is a surjective algebra homomorphism, so the descent algebra implicitly encodes information about the representations of the symmetric group. However, this property does not hold for other Coxeter groups. Moreover, a complete set of primitive idempotents in the descent algebra of the symmetric group leads to a decomposition of the group algebra as a direct sum of induced linear characters of centralizers of conjugacy class representatives. In this dissertation, I consider the hyperoctahedral group. When the descent algebra of a hyperoctahedral group is replaced with a generalization called the Mantaci-Reutenauer algebra, the natural map to the character ring is surjective. In 2008, Bonnafé asked whether a complete set of idempotents in the Mantaci-Reutenauer algebra could lead to a decomposition of the group algebra of the hyperoctahedral group as a direct sum of induced linear characters of centralizers. In this dissertation, I will answer this question positively and go through the construction of the idempotents, conjugacy class representatives, and linear characters required to do so.
Date: December 2016
Creator: Tomlin, Drew E

Defect Behaviors in Zinc Oxide and Zinc Titanates Ceramics from First Principles Computer Simulations

Description: ZnO and ZnO-TiO2 ceramics have intriguing electronic and mechanical properties and find applications in many fields. Many of these properties and applications rely on the understanding of defects and defect processes in these oxides as these defects control the electronic, catalytic and mechanical behaviors. The goal of this dissertation is to systematically study the defects and defects behaviors in Wurtzite ZnO and Ilmenite ZnTiO3 by using first principles calculations and classical simulations employing empirical potentials. Firstly, the behavior of intrinsic and extrinsic point defects in ZnO and ZnTiO3 ceramics were investigated. Secondly, the effect of different surface absorbents and surface defects on the workfunction of ZnO were studied using DFT calculations. The results show that increasing the surface coverage of hydrocarbons decreased the workfunction. Lastly, the stacking fault behaviors on ilmenite ZnTiO3 were investigated by calculating the Generalized Stacking Fault (GSF) energies using density functional theory based first principles calculations and classical calculations employing effective partial charge inter-atomic potentials. The gamma-surfaces of two low energy surfaces, (110) and (104), of ZnTiO3 were fully mapped and, together with other analysis such as ideal shear stress calculations.
Date: December 2016
Creator: Sun, Wei

Design and Manufacture of Molding Compounds for High Reliability Microelectronics in Extreme Conditions

Description: The widespread use of electronics in more avenues of consumer use is increasing. Applications range from medical instrumentation that directly can affect someone's life, down hole sensors for oil and gas, aerospace, aeronautics, and automotive electronics. The increased power density and harsh environment makes the reliability of the packaging a vital part of the reliability of the device. The increased importance of analog devices in these applications, their high voltage and high temperature resilience is resulting in challenges that have not been dealt with before. In particular packaging where insulative properties are vital use polymer resins modified by ceramic fillers. The distinct dielectric properties of the resin and the filler result in charge storage and release of the polarization currents in the composite that have had unpredictable consequences on reliability. The objective of this effort is therefore to investigate a technique that can be used to measure the polarization in filled polymer resins and evaluate reliable molding compounds. A valuable approach to measure polarization in polymers where charge release is tied to the glass transition in the polymer is referred to as thermally stimulated depolarization current (TSDC) technique. In this dissertation a new TSDC measurement system was designed and fabricated. The instrument is an assembly of several components that are automated via a LabVIEW program that gives the user flexibility to test different dielectric compounds at high temperatures and high voltage. The temperature control is enabled through the use of dry air convection heating at a very slow rate enabling controlled heating and cooling. Charge trapping and de-trapping processes were investigated in order to obtain information on insulating polymeric composites and how to optimize it. A number of material properties were investigated. First, polarization due to charges on the filer were investigated using composites containing charged and uncharged particles using ...
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Date: December 2016
Creator: Garcia, Andres

Determinants of Women's Autonomy in Nepal

Description: Nepal in recent times has witnessed a proliferation of community-based organization (CBOs). Established by local residents, CBOs are small level organizations that promote and defend the rights and interests of people especially that of minorities and the disadvantaged. One such minority group that CBOs greatly focus on are women. Despite dramatic increase in the number of CBOs in Nepal its impact on women is understudied. The purpose of this dissertation is to analyze the relationship between Nepalese women's participation in CBOs and their autonomy. Autonomy comprises of four different dimensions; physical mobility, financial autonomy, household decision-making, and reproductive autonomy. Modifying the conceptual framework used by Mahmud, Shah, and Becker in 2012, I hypothesize that women who participate in CBOs experience greater autonomy. Data from the 2008 Chitwan Valley Family Study is used for analysis. Using SPSS, separate logistic regressions are run to analyze the relationship between CBO membership and the dimensions of autonomy. The results support three of the four proposed major hypotheses. Nepalese women who participate in CBOs have greater autonomy in terms of physical mobility, financial autonomy, and household decision-making. No evidence was found to establish link between CBO membership and reproductive autonomy. The variables that are controlled for in the study include age, caste, religion, education, marital status, exposure to television, exposure to radio, and relationship with one's mother-in-law.
Date: December 2016
Creator: Neupane, Diptee

Dissimilar Friction Stir Welding Between Magnesium and Aluminum Alloys

Description: Joining two dissimilar metals, specifically Mg and Al alloys, using conventional welding techniques is extraordinarily challenging. Even when these alloys are able to be joined, the weld is littered with defects such as cracks, cavities, and wormholes. The focus of this project was to use friction stir welding to create a defect-free joint between Al 2139 and Mg WE43. The stir tool used in this project, made of H13 tool steel, is of fixed design. The design included an 11 mm scrolled and concave shoulder in addition to a 6 mm length pin comprised of two tapering, threaded re-entrant flutes that promoted and amplified material flow. Upon completion of this project an improved experimental setup process was created as well as successful welds between the two alloys. These successful joints, albeit containing defects, lead to the conclusion that the tool used in project was ill fit to join the Al and Mg alloy plates. This was primarily due to its conical shaped pin instead of the more traditional cylindrical shaped pins. As a result of this aggressive pin design, there was a lack of heat generation towards the bottom of the pin even at higher (800-1000 rpm) rotation speeds. This lack of heat generation prohibited the material from reaching plastic deformation thus preventing the needed material flow to form the defect free joint.
Date: December 2016
Creator: Reese, Gregory A

Dissimilar Joining of Al (AA2139) – Mg (WE43) Alloys Using Friction Stir Welding

Description: This research demonstrates the use of friction stir welding (FSW) to join dissimilar (Al-Mg) metal alloys. The main challenges in joining different, dissimilar metal alloys is the formation of brittle intermetallic compounds (IMCs) in the stir zone affecting mechanical properties of joint significantly. In this present study, FSW joining process is used to join aluminum alloy AA2139 and magnesium alloy WE43. The 9.5 mm thick plates of AA2139 and WE43 were friction stir butt welded. Different processing parameters were used to optimize processing parameters. Also, various weldings showed a crack at interface due to formation of IMCs caused by liquation during FSW. A good strength sound weld was obtained using processing parameter of 1200 rev/min rotational speed; 76.2 mm/min traverse speed; 1.5 degree tilt and 0.13 mm offsets towards aluminum. The crack faded away as the tool was offset towards advancing side aluminum. Mostly, the research was focused on developing high strength joint through microstructural control to reduce IMCs thickness in Al-Mg dissimilar weld joint with optimized processing parameter and appropriate tool offset.
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Date: December 2016
Creator: Poudel, Amir