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 Collection: UNT Theses and Dissertations
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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Continuous Combinatorics of a Lattice Graph in the Cantor Space

Continuous Combinatorics of a Lattice Graph in the Cantor Space

Date: May 2016
Creator: Krohne, Edward William
Description: We present a novel theorem of Borel Combinatorics that sheds light on the types of continuous functions that can be defined on the Cantor space. We specifically consider the part X=F(2ᴳ) from the Cantor space, where the group G is the additive group of integer pairs ℤ². That is, X is the set of aperiodic {0,1} labelings of the two-dimensional infinite lattice graph. We give X the Bernoulli shift action, and this action induces a graph on X in which each connected component is again a two-dimensional lattice graph. It is folklore that no continuous (indeed, Borel) function provides a two-coloring of the graph on X, despite the fact that any finite subgraph of X is bipartite. Our main result offers a much more complete analysis of continuous functions on this space. We construct a countable collection of finite graphs, each consisting of twelve "tiles", such that for any property P (such as "two-coloring") that is locally recognizable in the proper sense, a continuous function with property P exists on X if and only if a function with a corresponding property P' exists on one of the graphs in the collection. We present the theorem, and give several applications.
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Do Re Mi? Yes! Using Music and Visual Arts to Promote Thai Children's English Vocabulary Development

Do Re Mi? Yes! Using Music and Visual Arts to Promote Thai Children's English Vocabulary Development

Date: May 2016
Creator: Mathayomchan, Somsuda
Description: This research examines the efficacy, if any, of the Music and Visual Arts (MVA) program in improving the English vocabulary development of first grade Thai students. The researcher developed the Vocabulary Recognition Assessment (VRA) as a measure of English vocabulary development. It employs the accuracy and rapidity method of word recognition as a measurement of English language development in Thai children. Forty first grade Thai students in a Bangkok elementary school participated in the study. Participants were divided equally between an experimental group and a control group. During a nine-week period, students in the experimental group were instructed with the MVA strategy, while students in the control group were taught with the Visual Arts (VA) strategy. Paired sample t-test, ANOVA, and ANCOVA were used to analyze data from the VRA, to compare the pre-test and the post-test in terms of accuracy scores and rapidity scores of the control group and the experimental group. Data revealed that students instructed with the MVA strategy improved their English vocabulary development in terms of accuracy of word recognition significantly more than students taught English using the VA strategy. No significant difference was found between the MVA strategy and the VA strategy in terms of ...
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Intraoral Pressure and Sound Pressure During Woodwind Performance

Intraoral Pressure and Sound Pressure During Woodwind Performance

Date: May 2016
Creator: Bowling, Micah
Description: For woodwind and brass performers, intraoral pressure is the measure of force exerted on the surface area of the oral cavity by the air transmitted from the lungs. This pressure is the combined effect of the volume of air forced into the oral cavity by the breathing apparatus and the resistance of the embouchure, reed opening, and instrument’s back pressure. Recent research by Michael Adduci shows that intraoral pressures during oboe performance can exceed capabilities for corresponding increases in sound output, suggesting a potentially hazardous situation for the development of soft tissue disorders in the throat and velopharyngeal insufficiencies. However, considering that oboe back pressure is perhaps the highest among the woodwind instruments, this problem may or may not occur in other woodwinds. There has been no research of this type for the other woodwind instruments. My study was completed to expand the current research by comparing intraoral pressure (IOP) and sound pressure when performing with a characteristic tone on oboe, clarinet, flute, bassoon, and saxophone. The expected results should show that, as sound pressure levels increase, intraoral pressure will also increase. The subjects, undergraduate and graduate music majors at the University of North Texas, performed a series of musical ...
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Preferred Qualifications of Collegiate Athletic Directors: Opinions of Presidents and Athletic Directors

Preferred Qualifications of Collegiate Athletic Directors: Opinions of Presidents and Athletic Directors

Date: May 2016
Creator: Sheffield, Cinnamon
Description: This study explored the preparation methods, qualifications and criteria that both university and athletic directors deemed necessary when searching for athletic directors. Participants completed a survey via Qualtrics online software. Two different populations were sampled for this study: 651 university presidents and 651 athletic directors whose schools compete in either Division I or II in the NCAA, resulting in 96 abd 150 usable responses respectively. Participants in both groups were primarily white males with mean ages of 62 for presidents and 52 for the athletic directors. The study provided demographic information, educational history, professional experience, and prior careers of athletic directors. The rankings of the athletic were compared to the rankings of the presidents and identified consistenncies of opinions. The respondent groups were in agreement on the qualities and ranking of many dimensions of leadershihp in this role. The top seven, for both groups, in order, were ethics, budgeting and finances skills, fundraising, communications, sport leadership, strategic management and policy, and athletic administration. This information could be used as a guide for people who want to strategically maneuver up the ranks in athletics administration. Presidents might use the information as they prepare to hire candidates for the athletic director position.
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Comment peut-on être Persane ou Péruvienne ? On le devient.

Comment peut-on être Persane ou Péruvienne ? On le devient.

Date: May 2016
Creator: Daucourt, Monica Hazan
Description: Cette analyse littéraire examine les parallèles entre les deux romans Lettres persanes de Montesquieu (1721) et Lettres d'une Péruvienne de Françoise de Graffigny (1747) en se concentrant sur le sort des femmes et leur rébellion contre la claustration. Leurs révoltes transformatrices révèlent une volonté qui refuse et puis transcende les barreaux de leur captivité pour vivre librement. La philosophie de Simone de Beauvoir (1908-1986) personnifie leurs luttes pour devenir et exister, ce qui se traduit par leur capacité de dévoiler leur vraie nature. Elles se battent contre le néant de leurs existences où elles ne peuvent que succomber aux contraintes imposées. Elles se battent pour se définir et pour devenir. Cependant, c'est Graffigny qui nous offre une réponse plus proto-féministe dépassant les paramètres masculins de la société. Son livre répond directement aux Lettres persanes pour créer une nouvelle femme iconoclaste qui transcende les barrières de la société pour se réinventer.
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Highly Stretchable Miniature Strain Sensor for Large Dynamic Strain Measurement

Highly Stretchable Miniature Strain Sensor for Large Dynamic Strain Measurement

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Date: May 2016
Creator: Yao, Shulong
Description: This thesis aims to develop a new type of highly stretchable strain sensor to measure large deformation of a specimen subjected to dynamic loading. The sensor was based on the piezo-resistive response of carbon nanotube(CNT)/polydimethysiloxane (PDMS) composites thin films, some nickel particles were added into the sensor composite to improve the sensor performance. The piezo-resistive response of CNT composite gives high frequency response in strain measurement, while the ultra-soft PDMS matrix provides high flexibility and ductility for large strain measuring large strain (up to 26%) with an excellent linearity and a fast frequency response under quasi-static test, the delay time for high strain rate test is just 30 μs. This stretchable strain sensor is also able to exhibit much higher sensitivities, with a gauge factor of as high as 80, than conventional foil strain gauges.
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Decision Makers’ Cognitive Biases in Operations Management: An Experimental Study

Decision Makers’ Cognitive Biases in Operations Management: An Experimental Study

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Date: May 2016
Creator: Alkhars, Mohammed
Description: Behavioral operations management (BOM) has gained popularity in the last two decades. The main theme in this new stream of research is to include the human behavior in Operations Management (OM) models to increase the effectiveness of such models. BOM is classified into 4 areas: cognitive psychology, social psychology, group dynamics and system dynamics (Bendoly et al. 2010). This dissertation will focus on the first class, namely cognitive psychology. Cognitive psychology is further classified into heuristics and biases. Tversky and Kahneman (1974) discussed 3 heuristics and 13 cognitive biases that usually face decision makers. This dissertation is going to study 6 cognitive biases under the representativeness heuristic. The model in this dissertation states that cognitive reflection of the individual (Frederick 2005) and training about cognitive biases in the form of warning (Kaufmann and Michel 2009) will help decisions’ makers make less biased decisions. The 6 cognitive biases investigated in this dissertation are insensitivity to prior probability, insensitivity to sample size, misconception of chance, insensitivity to predictability, the illusion of validity and misconception of regression. 6 scenarios in OM contexts have been used in this study. Each scenario corresponds to one cognitive bias. Experimental design has been used as the research ...
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Community-based Logistics and Supply Chain Management: Developing, Testing and Validating Conceptual Models

Community-based Logistics and Supply Chain Management: Developing, Testing and Validating Conceptual Models

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Date: May 2016
Creator: Obaze, Yolanda
Description: The field of Logistics and Supply Chain Management (LSCM) suggests that transactions, collaboration, and value are important in the supply and delivery of products and services to meet the need of impoverished end-consumers. In many cases, the application of LSCM is paramount in most strategic decision-making efforts. Therefore, this research explores the applications of LSCM processes and activities within the community-based context. The methodology used to address the research questions consisted of a hybrid of mixed methods. This mixed methodology provides three essays that investigate the application and development of LSCM in the community-based context. The essays address the flow of charitable products and services through supply chains. The dissertation does not pay close attention to the first-tier suppliers’ suppliers, which is looking at the originating flow of goods and services (raw materials, manufacturing, etc.). However, the dissertation puts a focus on products and services supplied to focal organizations and how these products are then passed on to end-consumers. Essay I looks at the transaction (costs) that ensue from the supply of charitable products. Essay II analyzes a social service ecosystem and investigates how the network of organizations enable the distribution of charitable products and services. Lastly, Essay III examines ...
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'My Tattooed Mind'

'My Tattooed Mind'

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Date: May 2016
Creator: Mayo, Kaleb R
Description: This thesis features a collection of nonfiction essays.
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Ours is the Kingdom of Heaven: Racial Construction of Early American Christian Identities

Ours is the Kingdom of Heaven: Racial Construction of Early American Christian Identities

Date: May 2016
Creator: Robinson, Heather L
Description: This project interrogates how religious performance, either authentic or contrived, aids in the quest for freedom for oppressed peoples; how the rhetoric of the Enlightenment era pervades literatures delivered or written by Native Americans and African Americans; and how religious modes, such as evoking scripture, performing sacrifices, or relying upon providence, assist oppressed populations in their roles as early American authors and speakers. Even though the African American and Native American populations of early America before the eighteenth century were denied access to rights and freedom, they learned to manipulate these imposed constraints--renouncing the expectation that they should be subordinate and silent--to assert their independent bodies, voices, and spiritual identities through the use of literary expression. These performative strategies, such as self-fashioning, commanding language, destabilizing republican rhetoric, or revising narrative forms, become the tools used to present three significant strands of identity: the individual person, the racialized person, and the spiritual person. As each author resists the imposed restrictions of early American ideology and the resulting expectation of inferior behavior, he/she displays abilities within literature (oral and written forms) denied him/her by the political systems of the early republican and early national eras. Specifically, they each represent themselves in three ...
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Teaching beyond the walls:  A mixed method study of prospective elementary teachers’ belief systems about science instruction.

Teaching beyond the walls: A mixed method study of prospective elementary teachers’ belief systems about science instruction.

Date: May 2016
Creator: Asim, Sumreen
Description: This mixed method study investigated K-6 teacher candidates' beliefs about informal science instruction prior to and after their experiences in a 15-week science methods course and in comparison to a non-intervention group. The study is predicated by the literature that supports the extent to which teachers' beliefs influence their instructional practices. The intervention integrated the six strands of learning science in informal science education (NRC, 2009) and exposed candidates to out-of-school-time environments (NRC, 2010). Participants included 17 candidates in the intervention and 75 in the comparison group. All were undergraduate K-6 teacher candidates at one university enrolled in different sections of a required science methods course. All the participants completed the Beliefs about Science Teaching (BAT) survey. Reflective journals, drawings, interviews, and microteaching protocols were collected from participants in the intervention. There was no statistically significant difference in pre or post BAT scores of the two groups; However, there was a statistically significant interaction effect for the intervention group over time. Analysis of the qualitative data revealed that the intervention candidates displayed awareness of each of the six strands of learning science in informal environments and commitment to out-of-school-time learning of science. This study supports current reform efforts favoring integration ...
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Stable Nanocrystalline Au Film Structures for Sliding Electrical Contacts

Stable Nanocrystalline Au Film Structures for Sliding Electrical Contacts

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Date: May 2016
Creator: Mogonye, Jon-Erik
Description: Hard gold thin films and coatings are widely used in electronics as an effective material to reduce the friction and wear of relatively less expensive electrically conductive materials while simultaneously seeking to provide oxidation resistance and stable sliding electrical contact resistance (ECR). The main focus of this dissertation was to synthesize nanocrystalline Au films with grain structures capable of remaining stable during thermal exposure and under sliding electrical contact stress and the passing of electrical current. Here we have utilized a physical vapor deposition (PVD) technique, electron beam evaporation, to synthesize Au films modified by ion implantation and codeposited ZnO hardened Au nanocomposites. Simultaneous friction and ECR experiments of low fluence (< 1x10^17 cm^-2) He and Ar ion implanted Au films showed reduction in friction coefficients from ~1.5 to ~0.5 and specific wear rates from ~4x10^-3 to ~6x10^-5 mm^3/N·m versus as-deposited Au films without significant change in sliding ECR (~16 mΩ). Subsurface microstructural changes of He implanted films due to tribological stress were analyzed via site-specific cross-sectional transmission electron microscopy (TEM) and revealed the formation of nanocrystalline grains for low energy (22.5 keV) implantation conditions as well as the growth and redistribution of cavities. Nanoindentation hardness results revealed an increase ...
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Louis Vierne’s Pièces de Fantaisie, Opp. 51, 53, 54, and 55: Influence from Claude Debussy and Standard Nineteenth-Century Practices

Louis Vierne’s Pièces de Fantaisie, Opp. 51, 53, 54, and 55: Influence from Claude Debussy and Standard Nineteenth-Century Practices

Date: May 2016
Creator: Lee, Hyun Kyung
Description: The purpose of this research is to document how Claude Debussy’s compositional style was used in Louis Vierne’s organ music in the early twentieth century. In addition, this research seeks standard nineteenth-century practices in Vierne’s music. Vierne lived at the same time as Debussy, who largely influenced his music. Nevertheless, his practices were varied on the basis of Vierne’s own musical ideas and development, which were influenced by established nineteenth-century practices. This research focuses on the music of Louis Vierne’s Pièces de fantaisie, Opp. 51, 53, 54, and 55 (1926-1927). In order to examine Debussy’s practices and standard nineteenth-century practices, this project will concentrate on a stylistic analysis that demonstrates innovations in melody, harmony, and mode compared to the existing musical styles.
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Cross-cultural adjustment of self-initiated expatriates and individual work performance.

Cross-cultural adjustment of self-initiated expatriates and individual work performance.

Date: May 2016
Creator: Joshua-Gojer, Ashwini Esther
Description: Globalization in the past few decades has been marked by increased mobility of highly skilled workers from one country to another. Even though self-initiated expatriation is a widespread phenomenon, it is a relatively under-researched phenomenon in the academic literature, especially in an organizational context. Existing literature shows that not all individuals are equally suited to embark on a new life in another country, and self-initiated expatriates (SIEs) could be particularly susceptible to failure since they have no support from a home organization. This study was designed to investigate the experiences of self-initiated professional expatriates and the effect it had on their work performance. The purpose was to understand how their organizational and social experience affected their cross-cultural adjustment process and in turn affected their individual work performance. The researcher used a qualitative method using semi-structured interviews, observations, and documents with ten self-initiated expatriates. This study contributed to the expanding literature on the experiences of self-initiated expatriates, specifically how different support systems affected cross-cultural adjustment and individual work performance.
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The Mystery of the Chalumeau and Its Historical Significance as Revealed Through Selected Works for Chalumeau or Early Clarinet by Antonio Vivaldi

The Mystery of the Chalumeau and Its Historical Significance as Revealed Through Selected Works for Chalumeau or Early Clarinet by Antonio Vivaldi

Date: May 2016
Creator: Braun, Lindsay T.
Description: Factual evidence concerning the ancestry of the clarinet has been a perpetual topic of debate among musicologists and organologists. Scholars have widely agreed that the clarinet, first documented in 1710, emerged from the baroque invention of the chalumeau (invented circa 1690), which in itself was an improvement upon the recorder. Considering the chalumeau’s short lifespan as the predominant single reed instrument in the early eighteenth century, the chalumeau inspired a monumental amount of literature that includes vocal and instrumental genres written by distinguished composers. Vivaldi is considered to be the most significant composer that wrote for both clarinet and chalumeau; he wrote for both instruments simultaneously throughout his life whereas his contemporaries seemingly replaced the chalumeau with the clarinet. This project will discuss Vivaldi’s proximity to the chalumeau and the clarinet and will provide an in-depth analysis of relevant works by the composer to determine how he, unlike his contemporaries, treated the chalumeau and the clarinet as separate and equally viable instruments. Following a brief history of the chalumeau and clarinet in Italy and a relevant biography of Vivaldi (Ch. 2), this document will discuss the integral Vivaldi compositions that include clarinet and chalumeau and the role of the clarinet ...
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A Sequential Analysis of Therapist and Child Social Behavior Following a Conditioned Reinforcement Procedure

A Sequential Analysis of Therapist and Child Social Behavior Following a Conditioned Reinforcement Procedure

Date: May 2016
Creator: Cortez, Kristi Cathleen
Description: We conducted a contingency analysis to evaluate if a sequential relation between social initiations and positive social responses increased for both therapists and children with autism following a conditioned reinforcement procedure. Participants included child-therapist dyads, which were previously identified as having low rapport. These dyads were observed prior to and following an intervention designed to establish therapists' social behavior as a reinforcer. Sessions consisted of unstructured play between the therapist and child. Results from a Yule's Q analysis show that both the child and adult positive responding to the others' social initiations increased following the intervention. Findings highlight the reciprocal effects of therapist-child interactions as well as the effectiveness of establishing social attention as a reinforcer via an operant discrimination training procedure.
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Transmedia STEM Intervention Book in Middle School for Educational Change

Transmedia STEM Intervention Book in Middle School for Educational Change

Date: May 2016
Creator: Stansell, Alicia Renee
Description: The world is becoming a global place in which science, technology, engineering and mathematics hold a key to a successful future. To help secure this future it is important to engage students early with relevant curriculum that sparks interest and success in STEM fields. However, education reform occurs slowly, so this paper looked at a potential paradigm that can help to bring about change in a middle school environment that harnesses the long standing strengths of learning and education with the integration of technology to create changes in the pedagogy of learners and teachers. The study implemented a transmedia STEM book and evaluated the impact it had on student perceptions of STEM, school attitude, academic achievement, and preferred activity types, providing an example vehicle for change that can be adopted over time. The main findings showed that students who used a 3-Dimensional printer had higher math achievement and a more positive perception of math.
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Microstructural Phase Evolution In Laser Deposited Compositionally Graded Titanium-Chromium Alloys

Microstructural Phase Evolution In Laser Deposited Compositionally Graded Titanium-Chromium Alloys

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Date: May 2016
Creator: Thomas, Jonova
Description: A compositionally graded Ti-xCr (10≤x≤30 wt%) alloy has been fabricated using Laser Engineered Net Shaping (LENSTM) to study the microstructural phase evolution along a compositional gradient in both as-deposited and heat treated conditions (1000°C followed by furnace cooling or air cooling). The alloys were characterized by SEM BSE imaging, XRD, EBSD, TEM and micro-hardness measurements to determine processing-structure-property relations. For the as-deposited alloy, α-Ti, β-Ti, and TiCr2 (C15 Laves) phases exist in varying phase fractions, which were influential in determining hardness values. With the furnace cooled alloy, there was more homogeneous nucleation of α phase throughout the sample with a larger phase fraction of TiCr2 resulting in increased hardness values. When compared to the air cooled alloy, there was absence of wide scale nucleation of α phase and formation of ω phase within the β phase due to the quicker cooling from elevated temperature. At lower concentrations of Cr, the kinetics resulted in a diffusionless phase transformation of ω phase with increased hardness and a lower phase fraction of TiCr2. In contrast at higher Cr concentrations, α phase separation reaction occurs where the β phase is spinodally decomposed to Cr solute-lean β1 and solute-rich β2 resulting in reduced hardness.
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Analysis of Factors for Successful State-Level Support of Low-Performing Schools

Analysis of Factors for Successful State-Level Support of Low-Performing Schools

Date: May 2016
Creator: Ewing, Angela R.
Description: This study provides a qualitative look at Texas' Professional Service Providers' (PSPs) strategies for supporting low-performing schools. Four PSPs were selected for participation based on the number of schools they helped exit the Texas Title I School Improvement Program from 2007-2012. Data collected and analyzed included provider and principal interviews, providers' progress reports documenting services, and principals' evaluations of provider services. Results indicated key support strategies in two of four cases were supporting and mentoring/coaching while communicating and building trust were important in the other two cases. Communicating, reviewing information, and planning were important across all cases. The quality indicators aligning with the PSPs' strategies were fit, comprehensiveness, and coherence. They were also the most common across all cases. Finally, analysis of the evaluation of provider services revealed PSP-1 with the highest ratings, followed by PSP-2, PSP-3, and PSP-4 respectively. The findings suggest, first, that PSP support has a dual nature. Contextual support was provided based on the campus leaderships' skills and requests. PSPs also ensured coherence among the strategies of all stakeholders. Secondly, a hierarchy of quality service indicators aligned to the PSPs' strategies: fit, comprehensiveness, and coherence. Finally relationships are vital to a successful provider-campus relationship. The findings ...
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