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A Search for Periodic and Quasi-Periodic Patterns in Select Proxy Data with a Goal to Understanding Temperature Variation

A Search for Periodic and Quasi-Periodic Patterns in Select Proxy Data with a Goal to Understanding Temperature Variation

Date: May 2016
Creator: Otto, James
Description: In this work over 200 temperature proxy data sets have been analyzed to determine if periodic and or quasi-periodic patterns exist in the data sets. References to the journal articles where data are recorded are provided. Chapter 1 serves an introduction to the problem of temperature determination in providing information on how various proxy data sources are derived. Examples are given of the techniques followed in producing proxy data that predict temperature for each method used. In chapter 2 temperature proxy data spanning the last 4000 years, from 2,000 BCE to 2,000 CE, are analyzed to determine if overarching patterns exist in proxy data sets. An average of over 100 proxy data sets was used to produce Figure 4. An overview of the data shows that several “peaks” can be identified. The data were then subjected to analysis using a series of frequency modulated cosine waves. This analysis led to a function that can be expressed by equation 3. The literature was examined to determine what mathematical models had been published to fit the experimental proxy data for temperature. A number of attempts have been made to fit data from limited data sets with some degree of success. Some other ...
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Strategic Design: An Action Research Study on Community Relations in a Texas School District

Strategic Design: An Action Research Study on Community Relations in a Texas School District

Date: May 2016
Creator: Jund, Nicole Cathryn
Description: School leaders often contemplate implementing measures that will increase community and parent involvement in schools. There is a shortage of research that concisely takes school leadership through a process that details how to integrate parent and community input in a school transformation initiative and careful analysis of student outcomes. Within this study, I provide an in-depth look at one school district’s efforts to engage its community through strategic planning and mission and vision redesign. This process includes community involvement at every phase. For the purpose of this study, community refers to both community members who do not have children in the school system and parents of current students. In this study, I outline the inception of the transformation effort, the ongoing efforts to include community input in decision-making and campus implementation, and finally a review of the overarching impact on leadership, staff, students and community. Data collection analyzed in this study include assessment data, survey data, discipline data and walk through data collected by the school district.
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The Study of Temporal and Spatial Variability of Degree Day Factor of Snowmelt in Colorado

The Study of Temporal and Spatial Variability of Degree Day Factor of Snowmelt in Colorado

Date: May 2016
Creator: Pokhrel, Pranav
Description: Snowmelt is one of the major sources of surface water supply and ground-water recharge in high elevation areas and can also cause flooding in snow dominated watersheds. Direct estimation of daily snowmelt requires daily snow water equivalent (SWE) measurements that are not always available, especially in places without monitoring stations. There are two alternative approaches to modeling snowmelt without using direct measurements of SWE, temperature-based and energy-based models. Due to its simplicity, computational efficiency, and less input data requirement, the temperature-based method is commonly used than the energy-based method. In the temperature-index approach snowmelt is estimated as a linear function of average air temperature, and the slope of the linear function is called the degree-day factor (DDF). Hence, the DDF is an essential parameter for utilizing the temperature-based method to estimate snowmelt. Thereby, to analyze the spatial properties of DDF, 10 years DDF from the entire state of Colorado was calculated for this research. Likewise, to study the temporal properties, DDFs for 27 years from the White Yampa water basin and the Colorado Headwaters water basin were calculated. As a part of the spatial analysis, the calculated DDFs were correlated with spatial variables (slope, aspect, latitude and elevation) and a ...
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Causes of the Jewish Diaspora Revolt in Alexandria: Regional Uprisings from the Margins of Greco-Roman Society

Causes of the Jewish Diaspora Revolt in Alexandria: Regional Uprisings from the Margins of Greco-Roman Society

Date: May 2016
Creator: Vargas, Miguel M
Description: This thesis examines the progression from relatively peaceful relations between Alexandrians and Jews under the Ptolemies to the Diaspora Revolt under the Romans. A close analysis of the literature evidences that the transition from Ptolemaic to Roman Alexandria had critical effects on Jewish status in the Diaspora. One of the most far reaching consequences of the shift from the Ptolemies to Romans was forcing the Alexandrians to participate in the struggle for imperial patronage. Alexandrian involvement introduced a new element to the ongoing conflict among Egypt’s Jews and native Egyptians. The Alexandrian citizens consciously cut back privileges the Jews previously enjoyed under the Ptolemies and sought to block the Jews from advancing within the Roman system. Soon the Jews were confronted with rhetoric slandering their civility and culture. Faced with a choice, many Jews forsook Judaism and their traditions for more upwardly mobile life. After the outbreak of the First Jewish War Jewish life took a turn for the worse. Many Jews found themselves in a system that classified them according to their heritage and ancestry, limiting advancement even for apostates. With the resulting Jewish tax (fiscus Judaicus) Jews were becoming more economically and socially marginalized. The Alexandrian Jews were ...
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Biomass-Derived Activated Carbon through Self-Activation Process

Biomass-Derived Activated Carbon through Self-Activation Process

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Date: May 2016
Creator: Xia, Changlei
Description: Self-activation is a process that takes advantage of the gases emitted from the pyrolysis process of biomass to activate the converted carbon. The pyrolytic gases from the biomass contain CO2 and H2O, which can be used as activating agents. As two common methods, both of physical activation using CO2 and chemical activation using ZnCl2 introduce additional gas (CO2) or chemical (ZnCl2), in which the CO2 emission from the activation process or the zinc compound removal by acid from the follow-up process will cause environmental concerns. In comparison with these conventional activation processes, the self-activation process could avoid the cost of activating agents and is more environmentally friendly, since the exhaust gases (CO and H2) can be used as fuel or feedstock for the further synthesis in methanol production. In this research, many types of biomass were successfully converted into activated carbon through the self-activation process. An activation model was developed to describe the changes of specific surface area and pore volume during the activation. The relationships between the activating temperature, dwelling time, yield, specific surface area, and specific pore volume were detailed investigated. The highest specific surface area and pore volume of the biomass-derived activated carbon through the self-activation process ...
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The Perceptions of Policymakers on the Transfer Pathway in Texas Public Higher Education

The Perceptions of Policymakers on the Transfer Pathway in Texas Public Higher Education

Date: May 2016
Creator: Faris, Kimberly A
Description: Community college students transfer to public universities experiencing a pathway filled with complexity and inequity. Transfer students are not able to graduate at the same pace as native students at the university and complete their baccalaureate degrees 18% below the rate of native students. Policymakers have attempted to address the baccalaureate gap. This qualitative study explored the perspectives of Texas policymakers and policy influencers on the efficacy of policies intended to improve transfer outcomes. This study investigated what experience participants have with transfer policy, what their perceptions of the transfer pathway are, and how their voices can refine an understanding of policy development and ways to improve student persistence. Purposeful sampling was used to explore the perspectives of 14 Texas policymakers and those that influence policy. Findings revealed that significant gaps exist between expectations and student realities and that the completion agenda is driving policy decisions. Participants perceived that transfer students have been ignored in the completion metrics, which influence institutional priorities. Moreover, the decentralized system of independent, autonomous institutions is a major contributor to inefficiencies such as excessive student credit hours. Improving the transferability of courses was a priority recommendation of all participants both because it benefits the State’s ...
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Hungering for Independence: The Relationship between Food and Morale in the Continental Army, 1775-1783

Hungering for Independence: The Relationship between Food and Morale in the Continental Army, 1775-1783

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Date: May 2016
Creator: Maxwell, Nancy
Description: An adequate supply of the right kinds of foods is critical to an army's success on the march and on the battlefield. Good food supplies and a dire lack of provisions have profound effects on the regulation, confidence, esprit de corps, and physical state of an army. The American War of Independence (1775-1783) provides a challenging case study of this principle. The relationship between food and troop morale has been previously discussed as just one of many factors that contributed to the success of the Continental Army, but has not been fully explored as a single issue in its own right. I argue that despite the failures of three provisioning system adopted by the Continental Congress - the Commissariat, the state system of specific supplies, and the contract system - the army did keep up its morale and achieve the victory that resulted in independence from Great Britain. The evidence reveals that despite the poor provisioning, the American army was fed in the field for eight years thanks largely to its ability to forage for its food. This foraging system, if it can be called a system, was adequate to sustain morale and perseverance.
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Design of New Monodentate Ligands for Regioselectivity and Enantioselectivity Tuning in Late Transition Metal Catalysis

Design of New Monodentate Ligands for Regioselectivity and Enantioselectivity Tuning in Late Transition Metal Catalysis

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Date: May 2016
Creator: Ruch, Aaron Anthony
Description: The ability of gold(I) to activate many types of unsaturated bonds toward nucleophilic attack was not widely recognized until the early 2000s. One major challenge in gold catalysis is the control over regioselectivity when there are two or more possible products as a result of complicated mechanistic pathways. It is well know that the choice of ligand can have dramatic effects on which pathway is being followed but very rarely are the reasons for this selectivity understood. The synthesis of new acyclic diaminocarbenes was developed and a study of the ligand effects on the regioselectivity of a gold-catalyzed domino enyne cyclization hydroarylation reaction and a Nazarov cyclization was undertaken. New chiral acyclic diaminocarbenes were also developed and tested along side new C3-symmetric phosphite ligands in an asymmetric intramolecular hydroamination of allenes. Structure activity correlations were developed for the potential use in further rational ligand design. The synthesis of 6a,7-dihydro-5-amino-dibenzo[c,g]chromene derivatives via a gold-catalyzed domino reaction of alkynylbenzaldehydes in the presence of secondary amines was developed. These were sent to be screened for biological activity.
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The Controversial Identity of Flamenco Jazz: A New Historical and Analytical Approach

The Controversial Identity of Flamenco Jazz: A New Historical and Analytical Approach

Date: May 2016
Creator: Pamies Rodriguez, Sergio
Description: There are certain recordings by important artists such as Lionel Hampton, Miles Davis, John Coltrane, Pedro Iturralde, Chick Corea, and Paco de Lucía, among others, that have been associated with the label flamenco jazz. This label is entering jazz discourse, and it needs to be better understood in order to clarify its history, its identity, and its impact on recent developments in flamenco that are labeled nuevo flamenco. There is a lack of agreement in the existent literature on flamenco jazz on the evaluation of these recordings and these artists' achievements and contributions to this field. These writings encompass authors from different backgrounds: journalists, critics, and musicologists, who have approached their analysis of the recordings from different perspectives. The differences in professional backgrounds, approaches, and purpose of the writings of these authors has resulted in controversy about this label. Therefore, the flamenco jazz scholarly conversation needs more objective writings from an analytical point of view. This historiographical study presents a more comprehensive evaluation of flamenco jazz by discussing selected recordings using analytical tools from jazz studies. These analytical arguments clarify the aesthetics of flamenco jazz and the artistic processes that these artists went through when combining musical elements from flamenco ...
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Laser Ablation Inductively Coupled Plasma Mass Spectrometry and Raman Spectroscopy Imaging of Biological Tissues

Laser Ablation Inductively Coupled Plasma Mass Spectrometry and Raman Spectroscopy Imaging of Biological Tissues

Date: May 2016
Creator: Gorishek, Emma
Description: Laser Ablation Inductively coupled plasma mass spectrometry (LA-ICP-MS) and Raman spectroscopy are both powerful imaging techniques. Their applications are numerous and extremely potential in the field of biology. In order to improve upon LA-ICP-MS an in-house built cold cell was developed and its effectiveness studied by imaging Brassica napus seeds. To further apply LA-ICP-MS and Raman imaging to the field of entomology a prong gilled mayfly (Ephemeroptera: Leptophlebiidae) from the Róbalo River, located on Navarino Island in Chile, was studied. Analysis of both samples showcased LA-ICP-MS and Raman spectroscopy as effective instruments for imaging trace elements and larger molecules in biological samples respectively.
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Influence of High Strain Rate Compression on Microstructure and Phase Transformation of NiTi Shape Memory Alloys

Influence of High Strain Rate Compression on Microstructure and Phase Transformation of NiTi Shape Memory Alloys

Date: May 2016
Creator: Qiu, Ying
Description: Since NiTi shape memory alloy (SMA) was discovered in the early 1960s, great progress has been made in understanding the properties and mechanisms of NiTi SMA and in developing associated products. For several decades, most of the scientific research and industrial interests on NiTi SMA has focused on its superelastic applications in the biomedical field and shape memory based “smart” devices, which involves the low strain rate (around 0.001 s^-1) response of NiTi SMA. Due to either stress-induced martensite phase transformation or stress induced martensite variant reorientation under the applied load, NiTi SMA has exhibited a high damping capacity in both austenitic and martensitic phase. Recently, there has been an increasing interest in exploitation of the high damping capacity of NiTi SMA to develop high strain rate related applications such as seismic damping elements and energy absorbing devices. However, a systematic study on the influence of strain, strain rate and temperature on the mechanical properties, phase transformation, microstructure and crystal structure is still limited, which leads to the difficulties in the design of products being subjected to high strain rate loading conditions. The four main objectives of the current research are: (1) achieve the single loading and the control of ...
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Information Structures in Notated Music: Statistical Explorations of Composers' Performance Marks in Solo Piano Scores

Information Structures in Notated Music: Statistical Explorations of Composers' Performance Marks in Solo Piano Scores

Date: May 2016
Creator: Buchanan, J. Paul
Description: Written notation has a long history in many musical traditions and has been particularly important in the composition and performance of Western art music. This study adopted the conceptual view that a musical score consists of two coordinated but separate communication channels: the musical text and a collection of composer-selected performance marks that serve as an interpretive gloss on that text. Structurally, these channels are defined by largely disjoint vocabularies of symbols and words. While the sound structures represented by musical texts are well studied in music theory and analysis, the stylistic patterns of performance marks and how they acquire contextual meaning in performance is an area with fewer theoretical foundations. This quantitative research explored the possibility that composers exhibit recurring patterns in their use of performance marks. Seventeen solo piano sonatas written between 1798 and 1913 by five major composers were analyzed from modern editions by tokenizing and tabulating the types and usage frequencies of their individual performance marks without regard to the associated musical texts. Using analytic methods common in information science, the results demonstrated persistent statistical similarities among the works of each composer and differences among the work groups of different composers. Although based on a small ...
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Musical and Dramatic Functions of Loops and Loop Breakers in Philip Glass's Opera "The Voyage"

Musical and Dramatic Functions of Loops and Loop Breakers in Philip Glass's Opera "The Voyage"

Date: May 2016
Creator: Wu, Chia-Ying
Description: Philip Glass's minimalist opera The Voyage commemorates the 500th Anniversary of Christopher Columbus's discovery of America. In the opera, Philip Glass, like other composers, expresses singers' and non-singers' words and activities by means of melodies, rhythms, chords, textures, timbres, and dynamics. In addition to these traditional musical expressions, successions of reiterating materials (RMs, two or more iterations of materials) and non reiterating materials (NRMs) become new musical expressions. However, dividing materials into theses two categories only distinguishes NRMs from RMs without exploring relations among them in successions. For instance, a listener cannot perceive the functional relations between a partial iteration of the RM and the NRM following the partial RM because both the partial RM and the NRM are NRMs. As a result, a listener hears a succession of NRM followed by another NRM. When an analyst relabels the partial RM as partial loop, and the NRM following the partial RM as loop breaker, a listener hears the NRM as a loop breaker causing a partial loop. The musical functions of loops and loop breakers concern a listener's expectations of the creation, sustaining, departure, and return to the norm in successions of loops and loop breakers. When a listener associates ...
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The Information Behavior of Individual Investors in Saudi Arabia

The Information Behavior of Individual Investors in Saudi Arabia

Date: May 2016
Creator: Elwani, Nabil
Description: Information plays a significant role in the success of investment strategies. Within a non-advisory context, individual investors elect to build and manage their investment portfolios to avoid the cost of hiring professional advisors. To cope with markets’ uncertainty, individual investors should acquire, understand, and use only relevant information, but that task can be affected by many factors, such as domain knowledge, cognitive and emotional biases, information overload, sources’ credibility, communication channels’ accuracy, and economic costs. Despite an increased interest in examining the financial performance of individual investors in Saudi Arabia, there has been no empirical research of the information behavior of individual investors, or the behavioral biases affecting the investment decision making process in the Saudi stock market (SSM). The purpose of this study was to examine this information behavior within a non-advisory contextualization of their investment decision-making process through the use of an online questionnaire instrument using close-ended questions. The significant intervening variables identified in this study influence the individual investors’ information behavior across many stages of the decision making process. While controlling for gender, education, and income, the optimal information behavior of individual investors in the SSM showed that the Experience factor had the greatest negative effect on ...
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Forgotten Legacies: The U.S. Glider Pilot Training Program and Lamesa Field, Texas, During World War II

Forgotten Legacies: The U.S. Glider Pilot Training Program and Lamesa Field, Texas, During World War II

Date: May 2016
Creator: Garner, Christian A.
Description: Rapidly initiated at the national, regional, and local levels, the American glider pilot training program came about due to a perceived need after successful German operations at the outset of World War II. Although the national program successfully produced the required number of pilots to facilitate combat operations, numerous changes and improvisation came to characterize the program. Like other American military initiatives in the twentieth century, the War Department applied massive amounts of effort, dollars, and time to a program that proved to be short-lived in duration because it was quickly discarded when new technologies appeared. At the local level, the real loser was Lamesa, Texas. Bearing the brunt of these changes by military decision makers, the citizens of Lamesa saw their hard-fought efforts to secure an airfield fall quickly by the wayside in the wake of changing national defense priorities. As generations continue to pass and memories gradually fade, it is important to document and understand the relationship between this military platform that saw limited action and a small Texas town that had a similarly short period of significance to train the pilots who flew the aircraft.
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Identifying Breast Cancer Disparities in the African-American Community Using a Mixed Methods Approach

Identifying Breast Cancer Disparities in the African-American Community Using a Mixed Methods Approach

Date: May 2016
Creator: Morrissey, Natalie Noel
Description: Utilizing a mixed methods approach in assessing cities and metropolitan areas with the highest rates of breast cancer disparities in African-American communities, this study presents the Affiliate perspective of the Susan G. Komen non-profit organization in combination with available socioeconomic data and academic literature. Analyzed through an anthropological lens, qualitative and quantitative data illuminate the lived experiences and dynamic circumstances in which breast cancer disparities are disproportionately experienced in 21 of the nation’s populations of African-Americans. Two main recommendations arose from this research: prioritization of granting to activities such as patient navigation, usage of patient narrative messaging, community-based participatory research methods of program development and implementation, mobile mammography delivery, usage of lay health educators, and self-advocacy education to alleviate barriers to healthcare and supplementation of the current educational activities of the Komen Affiliates through program sharing and leverage of current assets with consideration of current Affiliate capacity. These recommendations may help in alleviating breast cancer disparities present in African-American communities with the highest levels of disparities in the nation.
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Understanding the Culture of Giving among Utility Fuel Fund Donors in Southern California

Understanding the Culture of Giving among Utility Fuel Fund Donors in Southern California

Date: May 2016
Creator: Sauer, Ashley
Description: The Energy Assistance Fund (EAF) is a voluntary, nonprofit fuel fund that provides grants to income qualified utility customers in an effort to help those customers avoid electricity service disconnection. The administering utility and the energy industry as a whole is undergoing transformative change, resulting in a projected decrease of fundraising capacity for EAF among its most substantial donor pool - utility shareholders and employees. Utility customers represent a small percentage of EAF donors, despite the significant size of the customer base. Through a series of ethnographic interviews and secondary research, this thesis seeks to understand the demographics and motivations of utility customers who donate to EAF in order to help improve EAF’s fundraising strategy and donor solicitations to eventually grow customer donations. The goal of EAF is to maintain or grow donations from 2014 levels so the Fund can continue to serve income qualified customers facing energy poverty. This thesis provides a contextual review of fuel funds; challenges faced by the energy and utility industry; the politics and culture of energy; as well as nonprofit sector fundraising challenges and cultures/motivations of giving. This thesis includes client deliverables such as thick description of donor motivation, motivation themes and a donor ...
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"Deborah": The Creation of a Chamber Oratorio in One Act

"Deborah": The Creation of a Chamber Oratorio in One Act

Date: May 2016
Creator: Mixter, Mary
Description: In comparing oratorio traits across history, three aspects of oratorio were found to be particularly applicable to the creation of "Deborah: A Chamber Oratorio in One Act." These aspects were: the selection of topic and the creation or adaptation of text; the differences between recitative and aria, in form and function; and the level of stylistic diversity within a given work.
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Impetuses for First, Second, and Third Year Law Student Information Seeking Behavior, and Perception of Common Knowledge and Citation

Impetuses for First, Second, and Third Year Law Student Information Seeking Behavior, and Perception of Common Knowledge and Citation

Date: May 2016
Creator: Helge, Kristyn Swen
Description: This dissertation examined how previous information literacy training, law student gender, age, and previously obtained education affects first, second, and third year law students selection of information sources, their understanding of common knowledge, and their decision of whether or not to give attribution to these sources. To examine these factors, this study implemented a paradigm called the principle of least effort that contended humans in general tended to complete the least amount of work possible to complete presented tasks. This study sought to discover whether law students follow this same path of completing the least amount of work possible to finish presented tasks, and whether this behavior affects information source selection, citation, and understanding of common knowledge. I performed six focus groups and crafted and disseminated an online survey to examine these factors. Via this data collection, it was discovered that law students do exhibit some differences in understanding of citation and citation behavior based on age and their year in law school. They also exhibited some differences regarding common knowledge based on their year in law school, where they received their information literacy training, and where they attend law school. Yet, no statistically significant differences were discovered regarding where ...
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An exploration of the word2vec algorithm: Creating a vector representation of a language vocabulary that encodes meaning and usage patterns in the vector space structure.

An exploration of the word2vec algorithm: Creating a vector representation of a language vocabulary that encodes meaning and usage patterns in the vector space structure.

Date: May 2016
Creator: Le, Thu Anh
Description: This thesis is an exloration and exposition of a highly efficient shallow neural network algorithm called word2vec, which was developed by T. Mikolov et al. in order to create vector representations of a language vocabulary such that information about the meaning and usage of the vocabulary words is encoded in the vector space structure. Chapter 1 introduces natural language processing, vector representations of language vocabularies, and the word2vec algorithm. Chapter 2 reviews the basic mathematical theory of deterministic convex optimization. Chapter 3 provides background on some concepts from computer science that are used in the word2vec algorithm: Huffman trees, neural networks, and binary cross-entropy. Chapter 4 provides a detailed discussion of the word2vec algorithm itself and includes a discussion of continuous bag of words, skip-gram, hierarchical softmax, and negative sampling. Finally, Chapter 5 explores some applications of vector representations: word categorization, analogy completion, and language translation assistance.
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"Deva Plus Dog"

"Deva Plus Dog"

Date: May 2016
Creator: Beavers, Hannah Michelle
Description: Deva Plus Dog is a look at the life of a teenage girl singularly devoted to the sport of dog agility. The film explores how relationships develop and evolve in the high stakes world of competition, and how an alternative lifestyle impacts a youth’s coming of age.
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Electrodeposited Metal Matrix Composites for Enhanced Corrosion Protection and Mechanical Properties

Electrodeposited Metal Matrix Composites for Enhanced Corrosion Protection and Mechanical Properties

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Date: May 2016
Creator: Thurber, Casey Ray
Description: In the oil and gas industry, high corrosion resistance and hardness are needed to extend the lifetime of the coatings due to exposure to high stress and salt environments. Electrodeposition has become a favorable technique in synthesizing coatings because of low cost, convenience, and the ability to work at low temperatures. Electrodeposition of metal matrix composites has become popular for enhanced corrosion resistance and hardness in the oil and gas industry because of the major problems that persist with corrosion. Two major alloys of copper-nickel, 90-10 and 70-30, were evaluated for microbial corrosion protection in marine environments on a stainless steel substrate. Copper and copper alloys are commonly used in marine environments to resist biofouling of materials by inhibiting microbial growth. Literature surveying the electrodeposition of Cu-Ni incorporated with nano- to micro- particles to produce metal matrix composites has been reviewed. Also, a novel flow cell design for the enhanced deposition of metal matrix composites was examined to obtain the optimal oriented structure of the layered silicates in the metal matrix. With the addition of montmorillonite into the Ni and Cu-Ni matrix, an increase in strength, adhesion, wear and fracture toughness of the coating occurs, which leads to an increase ...
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An Analysis of the Leadership Competency Frameworks of Nontraditional Principal Preparation Programs

An Analysis of the Leadership Competency Frameworks of Nontraditional Principal Preparation Programs

Date: May 2016
Creator: Horton, Tonya Marie
Description: This study explored the competency frameworks of nontraditional principal preparation programs to determine how they aligned to research-based best practices for school leaders. The research questions that guided this work were: To what degree are the McREL 21 Leadership Responsibilities addressed in the competency frameworks of nontraditional principal preparation programs? How do the leaders of the nontraditional principal preparation programs view the degree to which their competencies include the McREL 21 Leadership Responsibilities? A multi-case study analysis was conducted that compared the competency frameworks of four nontraditional principal preparation programs. The Knowledge is Power Program (KIPP), New Leaders, New York City Leadership Academy (NYCLA), and Teaching Trust were the nontraditional programs selected for this study. Leaders from the four organizations were interviewed. The findings from the research illustrated that a majority of the McREL 21 Leadership Responsibilities were included in the competency frameworks of nontraditional principal preparation programs. The study revealed that four of the McREL 21 were not included in any of the competency frameworks. Another finding was the lack of focus on talent management and personal dispositions in the McREL 21 Leadership Responsibilities. Nontraditional principal preparation programs are a growing avenue for principal preparation, as such their use ...
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Fatigue Behavior of A356 Aluminum Alloy

Fatigue Behavior of A356 Aluminum Alloy

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Date: May 2016
Creator: Nelaturu, Phalgun
Description: Metal fatigue is a recurring problem for metallurgists and materials engineers, especially in structural applications. It has been responsible for many disastrous accidents and tragedies in history. Understanding the micro-mechanisms during cyclic deformation and combating fatigue failure has remained a grand challenge. Environmental effects, like temperature or a corrosive medium, further worsen and complicate the problem. Ultimate design against fatigue must come from a materials perspective with a fundamental understanding of the interaction of microstructural features with dislocations, under the influence of stress, temperature, and other factors. This research endeavors to contribute to the current understanding of the fatigue failure mechanisms. Cast aluminum alloys are susceptible to fatigue failure due to the presence of defects in the microstructure like casting porosities, non-metallic inclusions, non-uniform distribution of secondary phases, etc. Friction stir processing (FSP), an emerging solid state processing technique, is an effective tool to refine and homogenize the cast microstructure of an alloy. In this work, the effect of FSP on the microstructure of an A356 cast aluminum alloy, and the resulting effect on its tensile and fatigue behavior have been studied. The main focus is on crack initiation and propagation mechanisms, and how stage I and stage II cracks ...
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