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The Useful Arts (open access)

The Useful Arts

This creative nonfiction dissertation is a series of braided narratives that chronicle the author's career as a trombonist in the John Smith Ensemble. As an amateur trombonist, the author is shocked to be hired as a professional musician for an orchestra that plays on PBS and at Carnegie Hall. She quickly realizes, however, that the job requires her to play the trombone quietly in front of an unplugged microphone while a CD recording of another, more talented trombonist is blasted out toward an unknowing audience. The job also requires the author to tour around America. The scenes of from this tour are braided with scenes wherein she reflects on her life as a professional fake musician and her past failed attempts at getting a job.
Date: August 2012
Creator: Hindman, Jessica
Object Type: Thesis or Dissertation
System: The UNT Digital Library
José Antonio Gómez´s Versos Para Órgano (Section I): a Practical Guide for Performance (open access)

José Antonio Gómez´s Versos Para Órgano (Section I): a Practical Guide for Performance

José Antonio Gómez is an important figure in Mexican music history and his works are considered representative of the beginning of Mexico´s Independent era. Some musicians are familiar with Gómez´s choral output but his organ music is rarely considered. Due to the lack of an edition of Gómez´s Versets for Organ, a practical guide was found needed to aid its performance. This study is based on performance, analysis, and direct work on the only known source for it. The first chapter, Introduction, presents the argument for an edited version of the first part of the manuscript as a performance guide. The second provides biographical information on the composer. The third chapter discusses the background for the original performance of the Versets for Organ. Chapter 4 provides performance considerations for the works. The edition of the manuscript is included in chapter 5.
Date: August 2012
Creator: Carrasco Curíntzita, Laura A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Real Analyticity of Hausdorff Dimension of Disconnected Julia Sets of Cubic Parabolic Polynomials (open access)

Real Analyticity of Hausdorff Dimension of Disconnected Julia Sets of Cubic Parabolic Polynomials

Consider a family of cubic parabolic polynomials given by for non-zero complex parameters such that for each the polynomial is a parabolic polynomial, that is, the polynomial has a parabolic fixed point and the Julia set of , denoted by , does not contain any critical points of . We also assumed that for each , one finite critical point of the polynomial escapes to the super-attracting fixed point infinity. So, the Julia sets are disconnected. The concern about the family is that the members of this family are generally not even bi-Lipschitz conjugate on their Julia sets. We have proved that the parameter set is open and contains a deleted neighborhood of the origin 0. Our main result is that the Hausdorff dimension function defined by is real analytic. To prove this we have constructed a holomorphic family of holomorphic parabolic graph directed Markov systems whose limit sets coincide with the Julia sets of polynomials up to a countable set, and hence have the same Hausdorff dimension. Then we associate to this holomorphic family of holomorphic parabolic graph directed Markov systems an analytic family, call it , of conformal graph directed Markov systems with infinite number of edges in …
Date: August 2012
Creator: Akter, Hasina
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico (open access)

Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico

In 1863, Fort Bascom was built along the Canadian River in the Eroded Plains of Territorial New Mexico. Its unique location placed it between the Comanches of Texas and the Comancheros of the Sangre de Cristo Mountains. This post was situated within Comanchería during the height of the United States Army's war against the Southern Plains Indians, yet it has garnered little attention. This study broadens the scholarly understanding of how the United States Army gained control of the Southwest by examining the role Fort Bascom played in this mission. This includes an exploration of the Canadian River Valley environment, an examination of the economic relationship that existed between the Southern Plains Indians and the mountain people of New Mexico, and an account of the daily life of soldiers posted to Fort Bascom. This dissertation thus provides an environmental and cultural history of the Canadian River Valley in New Mexico, a social history of the men stationed at Fort Bascom, and proof that the post played a key role in the Army's efforts to gain control of the Southern Plains Indians. This study argues that Fort Bascom should be recognized as Texas' northern-most frontier fort. Its men were closer to …
Date: August 2012
Creator: Blackshear, James Bailey
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Equivalence Classes of Subquotients of Pseudodifferential Operator Modules on the Line (open access)

Equivalence Classes of Subquotients of Pseudodifferential Operator Modules on the Line

Certain subquotients of Vec(R)-modules of pseudodifferential operators from one tensor density module to another are categorized, giving necessary and sufficient conditions under which two such subquotients are equivalent as Vec(R)-representations. These subquotients split under the projective subalgebra, a copy of ????2, when the members of their composition series have distinct Casimir eigenvalues. Results were obtained using the explicit description of the action of Vec(R) with respect to this splitting. In the length five case, the equivalence classes of the subquotients are determined by two invariants. In an appropriate coordinate system, the level curves of one of these invariants are a pencil of conics, and those of the other are a pencil of cubics.
Date: August 2012
Creator: Larsen, Jeannette M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Lind, James Meyer the Trumpet Concertos of Anthony Plog: a Performer’s Guide (open access)

Lind, James Meyer the Trumpet Concertos of Anthony Plog: a Performer’s Guide

Anthony Plog (b. 1947) has contributed several notable works for brass instruments. He is known for writing extremely technically challenging works that contain angular melodies, fast rhythms and a large degree of chromaticism. Though his music is difficult, it also conveys intense emotions. His music for trumpet, specifically Concerto no. 1 for Trumpet, Brass Ensemble and Percussion and Concerto no. 2 for Trumpet and Orchestra, represents a zenith in his compositional development. This dissertation examines Concerto no. 1 and Concerto no. 2 from a performer’s perspective to better understand the stylistic characteristics and challenges encountered in his music. Each concerto is examined in terms of rhythmic structure, intervallic structure, thematic material, motivic material and form.
Date: August 2012
Creator: Lind, James Meyer
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Mixed-methods Study Investigating the Relationship Between Media Multitasking Orientation and Grade Point Average (open access)

A Mixed-methods Study Investigating the Relationship Between Media Multitasking Orientation and Grade Point Average

The intent of this study was to examine the relationship between media multitasking orientation and grade point average. The study utilized a mixed-methods approach to investigate the research questions. In the quantitative section of the study, the primary method of statistical analyses was multiple regression. The independent variables for the study were media multitasking orientation, gender, age, and income. The dependent variable for the study was grade point average. Three out of four independent variables, namely, media multitasking orientation, gender and age were statistically significant predictors of grade point average. In the qualitative section of the study, seven participants were interviewed to determine how individual differences in media multitasking orientation manifest themselves in academic settings.
Date: August 2012
Creator: Lee, Jennifer
Object Type: Thesis or Dissertation
System: The UNT Digital Library
An Examination of Preferences for Social Presence in Online Courses with Regard to Personality Type (open access)

An Examination of Preferences for Social Presence in Online Courses with Regard to Personality Type

The purpose of this research was to examine the connections between personality types as illustrated by the Myers Briggs Type Indicator and the desire for social presence components within a technology based learning environment. Participants in the study were undergraduate and graduate students enrolled in an educational technology program at a public university in the State of Texas. The study employed a mixed-method qualitative approach that utilized a paired comparison evaluation, a personality assessment, and semi-structured interviews. Results showed that the components of organization and feedback were thought to best foster social presence in technology based learning environments and that there was no real difference between the personality types of introverts versus extroverts and judgers versus perceivers.
Date: August 2012
Creator: Rose, Daniel Merritt
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Zebrafish Von Willebrand Factor (open access)

Zebrafish Von Willebrand Factor

In humans, von Willebrand factor (vWF) is a key component in hemostasis and acts as a 'cellular adhesive' by letting the circulating platelets bind to exposed subendothelium. It also acts as a carrier and stabilizer of factor VIII (FVIII). A dysfunction or reduction of vWF leads to von Willebrand disease (vWD), resulting in bleeding phenotype which affects 1% of the population. Currently there are a variety of animal models used for the study of vWF and vWD; however, they do not possess the advantages found in zebrafish. Therefore, we set out to establish zebrafish as a model for the investigation of vWF and vWD through the use of bioinformatics and various molecular techniques. Using bioinformatics we found that the vWF gene is located on chromosome 18, that the GPIb? protein sequence is conserved. Confirmation of vWF production was shown by means of immunostaining and by RT-PCR, in thrombocytes as well as in veins and arteries. Evidence of vWF involvement in hemostasis and thrombosis was shown using MO and VMO technology to produce a vWD like phenotype, resulting in an increase in TTO and TTA, as well as a reduction in FVIII when blood was tested using the kPTT assay, coinciding …
Date: August 2012
Creator: Carrillo, Maira M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Minority Hiv Rates, Inequality, and the Politics of Aids Funding (open access)

Minority Hiv Rates, Inequality, and the Politics of Aids Funding

Since the 1990s, the HIV/AIDS epidemic has increasingly impacted minority groups in the United States, particularly African Americans. Why is this happening? Comparative studies of developing nations have convincingly established a relationship between concentrated poverty, ethnic boundaries, and lack of effective governmental response as contributing to high levels of infection in those countries. To date, however, no study has sought to apply these insights to the American context. This dissertation endeavors to show that, first, marginalization of U.S. sub-groups most at risk of infection is largely a product of poor health outcomes associated with concentrated urban poverty and economic stratification. Second, this sub-group marginalization is exacerbated by the politics of retrenchment which increasingly privatizes risks onto individuals, states, and non-governmental providers. The net result of these changes is a U.S. health care system too fractured to recognize and respond to changes in HIV/AIDS demographics.
Date: August 2012
Creator: Miles, Thomas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Conductor Awareness of, Knowledge of, and Attitude Toward Sound Intensity Levels Generated During Ensemble-based Instructional Activities in College-level Schools of Music (open access)

Conductor Awareness of, Knowledge of, and Attitude Toward Sound Intensity Levels Generated During Ensemble-based Instructional Activities in College-level Schools of Music

In 2011, the National Association of Schools of Music (NASM) took an official position to recognize the importance of hearing health and injury prevention as a standard for all member-accredited institutions. This is the largest national acknowledgement promoting hearing health and safety within the music discipline and among students seeking a music degree in the United States. The purpose of the study is to describe what conductors (i.e., instructors) of college-based ensembles know about hearing health and the generation of sound intensity levels. The study aimed to describe the 1) current state of conductors’ awareness and knowledge of sound intensity levels, 2) current attitudes of conductors toward learning and sharing knowledge of sound intensity levels, and 3) current teaching practices of conductors in regard to equipment usage (e.g. sound level meter, noise dosimeter, hearing protection devices) relating to sound measurement and exposure. Findings indicate 80.2% of conductors (N = 162, 66% employed by NASM-accredited institutions) agree that sounds generated during ensemble-based instructional activities (EBIAs) in college-level schools of music are capable of harming human hearing, but 24.1% “do not know” if EBIAs they conduct ever exceed sound intensity levels capable of harming human hearing, 54.9% do not know “what services …
Date: August 2012
Creator: Albin, Aaron J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Peer Created Motivational Climate in Youth Sport and Its Relationship to Psychological Outcomes and Intention to Continue in Sport Among Male Adolescents (open access)

The Peer Created Motivational Climate in Youth Sport and Its Relationship to Psychological Outcomes and Intention to Continue in Sport Among Male Adolescents

Social agents in the youth sport domain (coaches, parents, and peers) play a crucial role in developing the motivational approaches of youth sport athletes. One theory which has been useful in explaining the important role of such social agents has been Achievement Goal Theory (Nicholls, 1989). Specifically, Achievement Goal Theory was used to delineate various peer behaviors as being task-involving (Ntoumanis & Vazou, 2005) and was used to predict subsequent relationships relationship between the task-involving motivational-climate created by teammates and athletes’ mastery goal orientations and self-esteem, sport competence, enjoyment, and intention to continue playing sport. Participants were 405 boys aged 12-15 years. Using structural equation modeling, an exploratory analysis and confirmatory analysis revealed that higher levels of task-involving behaviors from peers predicted mastery goal orientation. Participants with higher mastery goal orientation reported greater sport competence, self-esteem, and more enjoyment; enjoyment was the strongest predictor of intention to continue. These findings both emphasize the importance of peer relationships within sport on a variety of motivationally and psychologically salient outcomes and provide direction for the development of training programs targeted to create positive and healthy sport experiences.
Date: August 2012
Creator: Atkins, Matthew R.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Multi-perspective, Multi-modal Image Registration and Fusion (open access)

Multi-perspective, Multi-modal Image Registration and Fusion

Multi-modal image fusion is an active research area with many civilian and military applications. Fusion is defined as strategic combination of information collected by various sensors from different locations or different types in order to obtain a better understanding of an observed scene or situation. Fusion of multi-modal images cannot be completed unless these two modalities are spatially aligned. In this research, I consider two important problems. Multi-modal, multi-perspective image registration and decision level fusion of multi-modal images. In particular, LiDAR and visual imagery. Multi-modal image registration is a difficult task due to the different semantic interpretation of features extracted from each modality. This problem is decoupled into three sub-problems. The first step is identification and extraction of common features. The second step is the determination of corresponding points. The third step consists of determining the registration transformation parameters. Traditional registration methods use low level features such as lines and corners. Using these features require an extensive optimization search in order to determine the corresponding points. Many methods use global positioning systems (GPS), and a calibrated camera in order to obtain an initial estimate of the camera parameters. The advantages of our work over the previous works are the following. …
Date: August 2012
Creator: Belkhouche, Mohammed Yassine
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Antigravity (open access)

Antigravity

This dissertation contains two parts: Part I, which discusses the elegy of possessive intent, a subgenre of the contemporary American elegy; and Part II, Antigravity, a collection of poems. English elegies have been closely rooted to a specific grief, making the poems closer to occasional poems. The poet—or at least the poet’s speaker—seeks some kind of public consolation for (often) a private loss. The Americanized form does stray from the traditional elegy yet retains some of its characteristics. Some American elegies memorialize failed romantic relationships rather than the dead. In their memorials, these speakers seek a completion for the lack the broken relationship has created in the speakers’ lives. What they can’t replace, they substitute with something personal. As the contemporary poem becomes further removed from tradition, it’s no surprise that the elegy has evolved as well. Discussions of elegies have never ventured into the type of elegy that concerns itself with the sort of unacknowledged loss found in some contemporary American poems of unrequited love. These poems all have speakers who willfully refuse to acknowledge the loss of their love-objects and strive to maintain control/ownership of their beloveds even in the face of rejection.
Date: August 2012
Creator: Bowen, Ashley Hamilton
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Kleinian Groups in Hilbert Spaces (open access)

Kleinian Groups in Hilbert Spaces

The theory of discrete groups acting on finite dimensional Euclidean open balls by hyperbolic isometries was borne around the end of 19th century within the works of Fuchs, Klein and Poincaré. We develop the theory of discrete groups acting by hyperbolic isometries on the open unit ball of an infinite dimensional separable Hilbert space. We present our investigations on the geometry of limit sets at the sphere at infinity with an attempt to highlight the differences between the finite and infinite dimensional theories. We discuss the existence of fixed points of isometries and the classification of isometries. Various notions of discreteness that were equivalent in finite dimensions, no longer turn out to be in our setting. In this regard, the robust notion of strong discreteness is introduced and we study limit sets for properly discontinuous actions. We go on to prove a generalization of the Bishop-Jones formula for strongly discrete groups, equating the Hausdorff dimension of the radial limit set with the Poincaré exponent of the group. We end with a short discussion on conformal measures and their relation with Hausdorff and packing measures on the limit set.
Date: August 2012
Creator: Das, Tushar
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Service Provisions for Youth with Emotional and Behavioral Disorders (open access)

Service Provisions for Youth with Emotional and Behavioral Disorders

Youth with emotional or behavioral disorders (EBD) have poorer outcomes compared to their peers with and without disabilities. As a result, the federal government has mandated transition services to improve supports and ultimately student outcomes. Using data from the National Longitudinal Transition Study-2 (NLTS-2), this secondary analysis looked at services provided to youth with EBD (n = 410). The purpose of the study was to show a relationship between utilization of multiple services and the attainment of paid employment, and/or attending post-secondary education. Results indicate relationships between receiving financial services, tutoring and educational services and vocational services with attending a post-secondary institution. Logistic regression indicated a relationship between time, age and amount or services with paid employment. These results indicate the need for continuous, systematic and linked services for youth with EBD well into their twenties.
Date: August 2012
Creator: Dean, Latoya Lavan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Child Rescue As Survival Resistance: Hidden Children in Nazi-occupied  Western Europe (open access)

Child Rescue As Survival Resistance: Hidden Children in Nazi-occupied Western Europe

The phenomenon of rescue organizations that devoted themselves specifically to hiding and saving Jewish children appeared throughout Nazi-occupied Western Europe (France, Belgium, and the Netherlands). Jewish and non-Jewish rescuers risked their lives to save thousands of children from extermination. This dissertation adds to the historiographical understanding of Holocaust resistance by analyzing the efforts of these child rescue organizations as a form of “survival resistance.” Researching the key aspects of traditional resistance (conscious intent, extensive organization, and effective turn-out) demonstrates that, while child rescue did not present armed resistance, it still was a form of active resistance against the Nazi Final Solution. By looking at rescuers’ testimonies and archival sources (from Yad Vashem, United States Holocaust Memorial Museum, Centre de documentation juive contemporaine, and Kazerne Dossin), this dissertation first outlines the extensive organization and intent of Jewish rescue groups, such as the Oeuvre de Secours aux Enfants (OSE) and Comité de défense des Juifs (CDJ), in France, Belgium, and the Netherlands. The second part looks at rescue organization and intent by Catholic, Protestant, and humanitarian groups. The dissertation concludes by discussing the effectiveness of organized child rescue. In the end, the rescue groups saved thousands of children and proofs that Child …
Date: August 2012
Creator: Decoster, Charlotte Marie-Cecile Marguerite
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Set for Life: a Novel (open access)

Set for Life: a Novel

This collection of six chapters is an excerpt from a novel based on the book of Job, as told through the viewpoint of a contemporary woman from Texas. A preface exploring the act of starting over, fictionally and creatively, precedes the chapters.
Date: August 2012
Creator: Coleman, Britta
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Korean Traditional Elements and Contemporary Compositional Techniques in Hyowon Woo’s Choral Music As Reflected in Gloria (open access)

Korean Traditional Elements and Contemporary Compositional Techniques in Hyowon Woo’s Choral Music As Reflected in Gloria

Among native Korean choral composers, Hyowon Woo has emerged as one of the most significant representatives of choral genre, both in Korea and internationally. She has created a new style of choral music that combines traditional Korean musical elements with contemporary Western compositional techniques, in a synthesis that generates new sonorities and effects. Her choral music falls into three basic categories: music employing direct quotation of Korean folk tunes or other elements, which produce typical Korean sonorities; music using Western practices, which produce modern and Western flavors; and music combining Korean traditional methods with modern Western concepts. Hyowon Woo’s unique contribution to contemporary Korean choral music is ideally represented by her Gloria, which will form the basis for this study. Because traditional Korean music culture has such a strong presence and influence on her choral compositions, detailed knowledge of these elements are essential for the study and performance of her work. The combination of traditional Korean music and Western contemporary techniques lies at the core of her compositional style, and is the principal focus of this study. A detailed understanding of these stylistic elements, both Korean and Western, and how they work together to achieve the composer’s purpose and vision, …
Date: August 2012
Creator: Chang, Yoonchung
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Child Teacher Relationship Training As a Head Start Early Mental Health Intervention for Children Exhibiting Disruptive Behavior:  an Exploratory Study (open access)

Child Teacher Relationship Training As a Head Start Early Mental Health Intervention for Children Exhibiting Disruptive Behavior: an Exploratory Study

This exploratory study examined the effectiveness of child teacher relationship training (CTRT) with at-risk preschool children exhibiting disruptive behavior. The participants included a total of 23 Head Start teachers and their aides, and children identified by their teachers as exhibiting clinical or borderline levels of externalizing behavior problems. Teacher participants included 22 females and 1 male; demographics were reported as 56% Hispanic ethnicity, 17% Black American, and 22% European American. Child participants included 15 males and 5 females; demographics were reported as 60% Hispanic, 30% Black American, and 10% European American. A 2 by 3 (Group x Repeated Measures) split plot ANOVA was used to analyze the data. According to teacher reports using the Teacher Report Form (C-TRF) and blinded raters’ reports using the Direct Observation Form (DOF) to assess disruptive behaviors, children whose teachers received the CTRT intervention demonstrated statistically significant decreases (p < .05) in externalizing behaviors on the C-TRF and total problems on the DOF from pre- to mid- to post-test, compared to children whose teachers participated in the active control group. The CTRT intervention demonstrated large treatment effects on both measures (C-TRF: ?p2 =.173; DOF: ?p2=.164) when compared to CD, revealing the practical significance of the …
Date: August 2012
Creator: Gonzales, Terri Lynn
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Cardinal Giovanni Battista De Luca: Nepotism in the Seventeenth-century Catholic Church and De Luca's Efforts to Prohibit the Practice (open access)

Cardinal Giovanni Battista De Luca: Nepotism in the Seventeenth-century Catholic Church and De Luca's Efforts to Prohibit the Practice

This dissertation examines the role of Cardinal Giovanni Battista de Luca in the reform of nepotism in the seventeenth-century Catholic Church. Popes gave very large amounts of money to their relatives and the burden of nepotism on the Catholic Church was very onerous. The Catholic Church was crippled by nepotism and unable to carry out its traditional functions. Although Cardinal de Luca and Pope Innocent XI worked tirelessly to end nepotism, they were thwarted in their attempts by apprehension among the Cardinals concerning conciliarism and concerning the use of reform measures from the Council of Trent; by Gallicanism and the attempts of the French King to exercise power over the French Church; and by the entrenchment of nepotism and its long acceptance within the Church. Cardinal de Luca and Innocent XI were not able to push through reforms during their lifetimes but Pope Innocent XII was able to complete this reform and pass a reform Bull. This dissertation has two complementary themes. First, a confluence of circumstances allowed for the unfettered growth of nepotism in the seventeenth-century Church to the point of threatening the well-being of the Catholic Church. Reform was not undertaken until the threat to Church finances was …
Date: August 2012
Creator: Cowan, H. Lee
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Motivation and Resilience in Art Education: Insight and Inspiration From the Lives and Careers of Two Taiwanese College Art Teachers (open access)

Motivation and Resilience in Art Education: Insight and Inspiration From the Lives and Careers of Two Taiwanese College Art Teachers

This narrative study explores how two Taiwanese college art teachers’ lives and teaching experiences illustrate the ways they cultivate resilience and motivation to sustain professional commitments amidst challenges in their teaching careers. I use the life story interview as my methodology and a three-dimensional space approach to code and analyze my data to retell their stories about how resilience and motivation have guided them as they negotiated dilemmas in teaching. The participants’ stories demonstrate that in order to be motivated, teachers must satisfy their basic needs, which, in the language of Maslow’s need theory, include secure income, safety, love and belonging, respect, and personal accomplishment. To be resilient, art teachers need to facilitate self-efficacy as an essential belief to face challenges, and they also must gain support from family members, students, school administrators, and fellow members of professional organizations as external support resources. This study also illuminates the significance of international educational exchanges, the teaching knowledge constructed through layers of life and professional experience, and the importance of creating dialogue to address teachers’ challenges. Recommendations for future study include exploring further the relationship between motivation and resilience, specifying how gender difference affects the ways participants tell their stories, investigating how …
Date: August 2012
Creator: Chang, Ya-Ping
Object Type: Thesis or Dissertation
System: The UNT Digital Library
First Principles Calculations of the Site Substitution Behavior in Gamma Prime Phase in Nickel Based Superalloys (open access)

First Principles Calculations of the Site Substitution Behavior in Gamma Prime Phase in Nickel Based Superalloys

Nickel based superalloys have superior high temperature mechanical strength, corrosion and creep resistance in harsh environments and found applications in the hot sections as turbine blades and turbine discs in jet engines and gas generator turbines in the aerospace and energy industries. The efficiency of these turbine engines depends on the turbine inlet temperature, which is determined by the high temperature strength and behavior of these superalloys. The microstructure of nickel based superalloys usually contains coherently precipitated gamma prime (?) Ni3Al phase within the random solid solution of the gamma () matrix, with the ? phase being the strengthening phase of the superalloys. How the alloying elements partition into the and ? phases and especially in the site occupancy behaviors in the strengthening ? phases play a critical role in their high temperature mechanical behaviors. The goal of this dissertation is to study the site substitution behavior of the major alloying elements including Cr, Co and Ti through first principles based calculations. Site substitution energies have been calculated using the anti-site formation, the standard defect formation formalism, and the vacancy formation based formalism. Elements such as Cr and Ti were found to show strong preference for Al sublattice, whereas Co …
Date: August 2012
Creator: Chaudhari, Mrunalkumar
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Correcting the Record: a Comparison of Vladimir Ashkenazy’s Urtext-based Edition of Pictures at an Exhibition with Orchestration By Ravel and Stokowski (open access)

Correcting the Record: a Comparison of Vladimir Ashkenazy’s Urtext-based Edition of Pictures at an Exhibition with Orchestration By Ravel and Stokowski

Modest Mussorgsky (1839-1881) never published his piano suite, Pictures at an Exhibition. The first publication of the Pictures was Nikolai Rimsky-Korsakov’s (1844-1908) piano edition in 1886, five years after Mussorgsky’s death. Among several piano editions of Pictures, Manfred Schandert’s urtext piano edition of 1984 has shed new light on the piano suite. The urtext edition is based on a facsimile of Mussorgsky’s autograph, and Schandert’s authoritative urtext contains all of Mussorgsky’s musical indications that previous editions neglected to include. Previous orchestrations based on less comprehensive editions include well-known orchestrations by Maurice Ravel (1875-1937) and Leopold Stokowski (1882-1977). Vladimir Ashkenazy (b. 1937), on the other hand, derived his orchestration directly from the Schandert edition. In this study I argue that Ashkenazy offers “corrections” to his predecessors, Ravel and Stokowski, whose orchestrations differ—at times radically—from Mussorgsky’s autograph. This dissertation thus will explore the significant features of Ashkenazy’s orchestration in relation to the urtext edition by comparing it to the orchestrations of Ravel and Stokowski. In an age of attempts to present “authentic” versions of past music, Ashkenazy’s orchestration provides an authenticity that other orchestrations lack. Ashkenazy’s orchestration of Pictures at an Exhibition provides conductors an alternative performance option that is both effective …
Date: August 2012
Creator: Choi, Hoon
Object Type: Thesis or Dissertation
System: The UNT Digital Library