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A Vlasov-Poisson Numerical model for Multipactor Analysis
Full text linkThis thesis report describes a Vlasov-Poisson finite difference time domain numerical model that simulates parallel plate multipactor. The Vlassov approach which neglects collisions is well suited for sich analysis since the mutlipactor phenomenon occurs under near-vacuum collisionless conditions. Thus, electron transport can be modeled as the motion of a fluid subject to the influence of an external electromagnetic field. The advection of the electron swarm is determined by solving the Vlasov equation using a Koren flux limited numerical scheme. A direct Poisson solver accounts for space charge effects that become significant as electron growth occurs, hence a self-consistent Vlasov-Poisson combination. Bombarding electrons undergo secondary electron emission (SEE) with an energy-dependent secondary electron yield (SEY) at the spatial boundaries of the simulation. The model is able to simulate electron swarm dynamics from multipactor onset to well into the saturation regime. Specific analyses are performed on the time dependent physics that evolve within a multipacting system. Various orders of multipactor are compared to one another, and an analysis of the simulation parameters which alter multipactor saturation values is also discussed. This unique numerical model is meant to present an alternative way of simulating multipactor growth. Our results are compared to the predictions of SPARK 3D (a commercial software) and available experimental data, with good agreement in both cases
Looking Backward Toward Progress: Re-evaluating Whiteness through Puritan Texts
No full textThis thesis takes a look back historically to link the Puritans’ ideological construction of whiteness to contemporary theoretical ideas of whiteness using Toni Morrison’s Playing in the Dark (1992) and Richard Dyer’s White (1997). The introduction begins with me detailing the theoretical frameworks that I’ll be applying to Puritan texts in order to show the legacy of whiteness. Through these theoretical frameworks, I discover that Puritans formed one foundation of the systemic racism which still exists in America today. This helps me uncover the racial and social injustice that American society has conveniently ignored. If Americans continue to ignore these habits that privilege whiteness, then these habits will continue to replicate themselves in the social, political, and economic spheres. I use whiteness as a lens to focus on the construction of a collective consciousness of white identity that John Cotton, Cotton Mather, John Winthrop, and Robert Cushman used to form communities and exclude others.
Using Maryse Condé’s I, Tituba, the Black Witch, published in 1992, and Morrison’s A Mercy 2008, I read the novels in relation to a long tradition of black feminist thought, specifically, as outlined in Patricia Hill Collins’s Black Feminist Thought. These novels provide an insight into the psyche of colonial America and illuminate important questions regarding racialized legitimization, privilege, and transnational dimensions of slavery. Black women acquire a perspective that Collins calls the ‘outsider-within’ stance where black women are able to “have a distinct view of the contradictions between the dominant group’s actions and ideologies” (11). In effect, I am using Condé’s and Morrison’s novels to discuss issues of diasporic identity and memory that are important to the tradition of black feminist thought
Copula Theory in Stress-Strength Reliability Estimation and Inference: Applications to the Burr X and Lomax Distributions
Full text linkIn this dissertation, the main focus is the concept of stress-strength reliability, a highly
applicable concept in engineering, computing, and medicine. Two distributions which
exemplify dependence models for study of estimation techniques are considered: a
multivariate Burr X distribution and the Multivariate Lomax distribution of Nayak (1987).
The Burr X distribution is considered to its demonstrated applicability and previously
determined results. Ahmad et al. (1997) and Surles and Padgett (1998) studied
stress-strength reliability for the Burr X distribution, and Surles and D'ambrosio (2004)
demonstrated the particular usefulness of the Burr Type X distribution in analyzing the
strength of carbon bers. The rst section of this dissertation highlights certain properties
of the Burr X distribution, as well as copula models and their usefulness in constructing
multivariate models with desired marginal distributions. The Lomax model is considered
due to a unique aspect of the dependence structure of its multivariate extension, which will
be further explained, and the modied estimation procedures needed to analyze such data.
This distribution is also introduced in the rst section. Finally, the rst section also
introduces the idea of stress-strength reliability and some prior research done in this area.
The second section of the dissertation introduces a new bivariate Burr X distribution
constructed from the Eyraud-Gumbel-Morgenstern copula model, describes the two-stage
parameter estimation procedure described by Joe (2005), and nds asymptotic results for
both the two-stage procedure and the typical maximum likelihood approach. In the third
section, the Multivariate Lomax distribution is introduced, and an alternative to ML
estimation are discussed. In addition, a result which reduces Ser
ing's condition for
asymptotic normality of ML estimators in high dimensions is given. In the fourth section,
asymptotic results for stress-strength reliability estimators for the multivariate Burr X
distribution are discussed. In the fth section, the same is done for the Multivariate Lomax
distribution. In the subsequent sections, a simulation study is discussed and the results
displayed. In the nal section of the dissertation, intended topics of further research are
discussed
Addition of Ticarcillin-Clavulanic Acid to INRA96 Extender in the Extension and Storage of Equine Semen: An Examination of its Effect on Semen Motion Characteristics and Viability
Full text linkThe use of stallion semen extenders containing antimicrobials is increasingly common in equine breeding facilities. Breeders now have numerous options for commercially available semen extenders for use in fresh, cooled semen. Commercially produced semen extenders, such as INRA 96®, commonly contain antimicrobials that may have limited efficacy. When this is a concern, many breeding facilities in the United States rely on the addition of ticarcillin-clavulanic acid to inhibit or eliminate possible bacterial growth. This practice, however, needs standardization from proven data.
The focus of this study was on evaluating the effects of the addition of ticarcillin-clavulanic acid, Timentin®, to INRA 96. This included assessing the effect of different extender and antimicrobial storage conditions on sperm motion characteristics, sperm membrane integrity and antimicrobial effectiveness. Fourteen mature, actively breeding Quarter Horse stallions were collected and 42 gel-free semen ejaculates were diluted with INRA 96 extender and stored for 24 hours in Equitainer II units.
Post storage evaluations consisted of sperm motion characteristics analysis by a computer-assisted analysis device, sperm membrane integrity evaluation by fluorescent measurements and bacterial isolation cultures for both aerobic and anaerobic bacteria. Data evaluation included analysis-of-variance and chi-square statistical methods with the P value for significance predetermined to < 0.05.
Significant reduction in sperm motion characteristics, total motility, progressive motility and sperm membrane integrity, after 24 h of cooled storage were found in treatments that were subjected to freezing and thawing of modified or unmodified extender prior to use. The addition of reconstituted ticarcillin-clavulanic acid to the extender prior to use resulted in higher sperm velocity when treatments were exposed to cooled storage rather than frozen. Bacterial isolates were cultured from neat semen in only 28 of 42 ejaculates (67%). The addition of ticarcillin-clavulanic acid to INRA 96 was no different than the use of INRA 96 alone for the inhibition of bacterial growth (98% vs. 94%).
The addition of ticarcillin-clavulanic acid at a dose rage of 1 mg/ml to INRA 96 extender did not negatively impact sperm motion characteristics and viability in extended semen after cooled storage. The act of freezing and thawing of extender prior to use did however have negative effects on sperm quality. This trial was conducted on a commercial breeding facility that did not have any cases of Pseudomonas aeruginosa or Klebsiella pneumoniae. Thus, additional studies are needed using samples that could be subjected to such pathogens.
Results of this study suggest that INRA 96 extender should not be exposed to freezing and thawing prior to use. Bacterial cultures of the extender treatments indicated effective inhibition of bacterial growth when compared to neat semen
Missing women in Japanese elections: The institutional basis of female underrepresentation
Full text linkOver the past 70 years since the end of the Second World War, the levels of Japanese women’s representation in the Lower House have shown significant changes under the different electoral systems: a large constituency system, a multi-member district system with a single non-transferable vote (MMD-SNTV), and a mixed system of single-member district (SMD) and proportional representation (PR). Such corresponding changes indicate the apparent impacts of the electoral systems on Japanese women’s representation.
This project takes an institutional approach to explain the representation of Japanese women in the Lower House. For the analysis of the MMD-SNTV system, I focus exclusively election-specific factors that affect the election of women. In this analysis, I take into account the features of Japanese politics that contributed those factors during the use of this system. I find that Japan’s single ballot rule lowered the electability of female candidates, limiting the positive effects of multi-member district (MMD) systems.
The analysis of the mixed system focuses on explicating the mechanism of the operation of the system. I find that the close link between the SMD and the PR reduces the proposed benefits of the PR by means of Japan’s unique rules of equal ranking on the party lists and best-loser ratios. In the end, the low electability of female candidates in the SMD and their reduced competitiveness in the PR account for preventing female candidates from enjoying the benefits of the PR unless parties provide them with preferential placements on the lists
Written and Recorded Preparation Guides: Selected Repertoire from the University Interscholastic League Prescribed List for Flute and Piano
Full text linkMiddle school and high school students in Texas participating in the University Interscholastic League (UIL) Solo-Ensemble Contest are required to perform repertoire from the Texas Prescribed Music List (PML). The repertoire is graded according to level of difficulty from Class I to Class III, with I being the most musically and technically challenging and III the most technically accessible. This project includes four practice guides with recordings for selected Class I solos: Gigue (1728), by Jean-Marie LeClair (1697–1764); “Papillon,” op. 30, no. 4, by Ernesto Köhler (1849–1907); “La Chasse Galop Brillant,” op. 250, no. 6, by Wilhelm Popp (1819); and Sonata for Flute and Piano (1849–1907) by Gaetano Donizetti (1797–1848).
Throughout the state of Texas, many music students live in metropolitan areas with programs supported by private lesson programs. In cases where private lessons are not supported through the school district, many have the financial resources to seek and obtain individual private instruction. Through private instruction, students are able to receive guidance regarding musical expression including verbal suggestions for phrasing, vibrato, dynamics, articulation, fingerings, and intonation. Additionally, students’ aural skills and sound concepts are developed through their imitation of their teachers’ playing. However, many students are not financially positioned to pay for private instruction, live in rural areas without access to specialized private teachers, or attend low-income schools where private instruction is unavailable. In such cases, many rely solely on the instruction of their band directors. These band directors may not be in a position to effectively guide the flute student, based on the availability of their time or their knowledge and skill base related to flute playing. Students are often faced with having to prepare repertoire on their own. As a result, many look to published practice guides and audio recordings for inspiration.
The UIL flute PML contains many pieces for which there are existing practice guides and audio recordings. However, there are also many quality works on the list for which no such guides or recordings exist.
Upon reviewing the Texas Prescribed Music List , the repertoire for this project was selected based on four criteria.
1. Each selected work is included on the Texas UIL Class I list. Students who are looking to advance past their regional competition to State Solo and Ensemble Contest are required to select a Class I solo from this list.
2. Each selected work is a technical showpiece that allows the performer to develop instrumental technique as well as musicianship.
3. For each work selected, no easily accessible recording is currently available.
4. For each work selected, no published practice guide currently exists (based on a survey of RILM, JSTOR, and Worldcat, as well as the available indexes for Flute Talk and Flutists Quarterly).
The four pieces used for this project have been edited and arranged by different flutists. This paper suggests recommendations to be applied to the original editions of the music, recommendations which are more tasteful than those found in George Pope’s edition, and which are not limited to Pope’s ideas.
Methodology
Practice Guides:
Each practice guide includes a step-by-step process detailing the following components:
1. A brief biographical background of each composer and historical information regarding the composition of the work
2. A visual diagram of the formal structure of each work
3. Specific practice techniques for each composition (for example, octave slur, flutter tonguing, and extended techniques exercises)
4. Complementary dynamics
5. Suggestions for rubato, tempo, and interpretation
6. Phrase markings
7. Suggested interpretations of articulation
8. Intonation tendencies for various registers as well as specific notes
9. Alternate fingerings to assist with intonation and technical facility
10. Vibrato suggestions related to context
11. Suggested practice rhythms for difficult passages
12. Suggested breathing
Recordings:
Selected works are professionally recorded and edited. These works will also be made available through iTunes and other digital distribution sites in the future.
Through the availability of practice guides and accessible recordings, students will be able to receive information that would previously have been available only through a private lesson teacher. This has the potential to allow students to self-guide their preparation of these works.
Open Educational Resource Advocacy: Examining Strategies and Resources for OER Supporters
Full text linkIt is not easy to bring an open educational resource (OER) into existence, but after all that work, creators are sometimes dismayed to find that their OER does not gain traction with their intended audience. Once the OER—be it a textbook or other material—is produced, what is next? How will other educators know that the newly composed OER exists, and why should they want to adopt it for their classrooms? The library can help. Three academic librarians successfully received an Affordable Learning Georgia Research Grant, the purpose of which was to conduct research on OER sustainability and advocacy. The grant team recruited a data analyst, and together they conducted a qualitative research study using an online survey instrument and received 98 responses from librarians and OER creators. Themes that emerged from the study include challenges (i.e. lack of time, energy, and support), communication and engagement (i.e., at events and other programming), and structured strategies (i.e., encouraging faculty and other creators to update their materials). Findings revealed that depositing into collections, making recommendations, and sharing via word of mouth and listservs are practical strategies and resources for OER creators and advocates. The article concludes with steps librarians and supporters can take to help OER creators design an advocacy plan and prioritize outreach.The research project and research team were funded through an ALG Affordable Materials Grant: Research Grants, Round 24, Grant RG008, to the amount of $10,000
Boron nitride coatings for the enhanced detection of neutrons in CR-39
Full text linkThe neutron detection efficiency of Columbia Resin 39 (CR-39) nuclear track detectors was assessed for AmBe, 252Cf, and D-T (14 MeV) neutron source spectra. A boron nitride (BN) coating for CR-39 was developed to enhance the neutron detection efficiency by converting neutrons into energetic alpha particles through the well-known 10B (n,α)7Li reaction. Separate partially coated CR-39 pieces were exposed to each neutron source and subsequently analyzed under optical microscope and through large-area Scanning Electron Microscopy (SEM) imaging over the irradiated area. The detection efficiency (tracks per neutron) was evaluated for each source spectra under optical and scanning electron microscopes and with or without BN coating. This resulted in a comprehensive guide to neutron detection with various sources using CR-39.This work was supported by the Department of Energy award No. DE-AR0001736
La imagen de la detective y el elemento femenino en La Trilogía del Baztán y La cara norte del corazón de Dolores Redondo
No full textThe purpose of this study is to analyze the crime narrative of contemporary Spanish-speaking author Dolores Redondo. It aims to characterize the feminine elements of her fictional world, with emphasis in the Basque mythology, and how they contribute to the creation of the image of the female detective. My objective is to argue that Dolores Redondo – in the four novels here studied -- presents an image of the female detective which is unique (and possibly “influential”) in the context of the lineage of female detectives in the genre of “detective fiction”, as created by Spanish female authors since – one may argue – Emilia Pardo Bazán. Furthermore, based on the unique circumstances surrounding Dolores Redondo’s impact on the literary world and beyond, such as her faithful readership and visibility in pop culture and society – I argue that this creation of Dolores Redondo, this “new” image of the female detective, may have a lasting effect in the field and it may help shape it in the future.
As mentioned, I contend that Dolores Redondo’s main contribution to the genre is her main character, inspector Amaia Salazar. In her highly successful trilogy and prequel, titled La trilogía del Baztán y La cara norte del corazón, the Spanish novelist draws on ancient beliefs and the origins of her own culture, reflecting, in her prose, the traditions of Basque-Navarrese mythology. In her fiction, I will attempt to characterize the female character, Amaia. While doing this, I plan to show that this character is portrayed in such a way that it subverts the formulas and parameters of the genre -- particularly in what concerns the image of the female detective -- while enriching the world of Spanish crime novels.
Through the analysis of the mentioned books, this work showcases the history and evolution of the protagonist, who seems to develop the characteristics of the myth of the heroine embarking on a quest. However, in this case, the journey that the heroine undertakes is filled with internal gender conflicts and her “unconscious,” in a sense, is represented by the mythological world of the Basque-Navarre region. The detective -- as I present her in this work – appears to represent a possible redefinition of the female figure, making her unique in the context of Spanish crime narratives written by women. To support my arguments, I follow the theories of Carl Gustav Jung, Maureen Murdock, and Joseph Campbell. Additionally, to substantiate my ideas concerning the mythological world of Baztán and the conflict of the psyche, I turn to the studies of José Miguel de Barandiarán and Clarissa Estés Pinkola.
My dissertation consists of an introduction, four chapters, and a conclusion. The introduction provides a more general context of the work. Chapter one offers a general understanding of the history of the crime novel, beginning with its creator, Edgar Allan Poe, and his followers; and leading up to Latin America & Spain, with its various names and characteristics developed over time. Chapter two analyzes the theoretical sources used in the thesis. Chapter three explores the folklore and myths of the Basque-Navarre region and how these elements help represent the nature, strength of the female character and her connection to the environment. In chapter four, I attempt a more detailed psychological and anthropological portrait of the main character, showing how the heroine completes her journey of self-discovery
Death Anxiety Among College Students: A Qualitative Study
No full textDeath has been defined as the discontinuance of brain and heart function. Regardless of age, race, ethnic group, or socioeconomic status all individuals must face death. According to death records, approximately 60 million deaths occur each year. Although all individuals must face death, individuals vary in how they manage this inevitability. For example, some individuals face an intense fear of death or the dying process, known as thanatophobia, while other individuals have little to no fear, or even peace. Although thanatophobia may not be present, some form of death anxiety is often experienced. While there are a number of articles reviewing death generally, there is a paucity of research regarding death anxiety. Specifically, there is a lack of research reviewing college student’s experiences of death anxiety. Using a qualitative research model with a grounded theory variant, this study is designed to study death anxiety experiences by college students