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Analysis of Students' Knowledge, Perceptions, and Interest in Engineering Post Teacher Participation in a National Science Foundation (NSF) Research Experience for Teachers (RET) Professional Development
This study examined the impact of the National Science Foundation's Research Experience for Teachers (RET) in engineering at University of North Texas on students after their teachers' participation in the program. Students were evaluated in terms of self-efficacy, knowledge of engineering, perceptions of engineering, and interest in engineering. A 22-item Likert pre/post survey was used for analysis, and participants included 589 students from six high schools, one middle school, and one magnet school. Paired surveys were analyzed to determine if there was a statistically significant difference in attitudes and knowledge after teachers implemented lessons from their time at the RET. Surveys were also analyzed to determine if there was a statistically significant difference in student response based on gender or student school type. Results showed no statistically significant difference in the self-efficacy of students, however there was a statistically significant difference in knowledge, perceptions, and interest in engineering. In addition, there was a statistically significant difference between genders on an isolated question, and seven out of the 22 Likert questions showed a statistically significant difference between student school types.
Analysis of Texas Education Agency Commissioner of Education Decisions Regarding Superintendent, Associate Superintendent, School Administrator, Athletic Director and Central Office Administrator Term Contract Nonrenewal Appeals From 1983 to 2013
I conducted a legal analysis of decisions by Texas Commissioners of Education in appeals by Texas school administrators from nonrenewal decisions made by Texas school districts from 1983 to 2013. I analyzed the findings of fact and conclusions of law described in the commissioners’ rulings to determine the legal basis of school districts’ decisions to nonrenew school administrators’ term employment contracts. I also examined the legal rationale for commissioners’ rulings and determined which party most commonly prevailed in these administrative proceedings—the respondent school district or the petitioner school administrator. In particular, the study determined factors that contributed to commissioners’ decisions to overrule or support school districts’ nonrenewal decisions. A careful review of commissioner decisions, which are accessible on the Texas Education Association website, identified 44 commissioner decisions involving appeals by superintendents, associate superintendents, public school administrators, athletic directors, or central office administrators concerning school districts’ term contract nonrenewal decisions from 1983 to 2013. Commissioners’ decisions in these cases were surveyed using legal research methods. This study provides recommendations to assist local education agencies to refine current policies and regulations regarding the nonrenewal of administrators’ term contracts, and provides insight on Texas Commissioners’ rulings on term contract nonrenewal appeals brought by Texas school administrators. The findings revealed that school boards’ lack of understanding of local policies and lack of evidence resulted in commissioners granting 27% of appeals. Additionally, commissioners denied 73% of the appeals because school boards provided at least one reason that met the substantial evidence standard of review, and respondents failed to substantiate allegations or enter evidence in evidentiary hearings.
An Analysis of the 4:2:1 Documentary
As a Chinese filmmaker, I feel obligated to reveal a true story about Chinese international students. Through my subjects and my stories, I am planning to express the messages that both adapting to a new culture and paying the financial cost of a foreign education have never been simple, but we will never give up our dreams.
An Analysis of the Correspondence Between the Measures Collected by an Autism Treatment Center and its Stated Mission Goals
This study was a program evaluation for an autism treatment center for the period of April 2008 through August 2011. the study extended previous evaluations of the autism treatment center. the purpose of this evaluation was to determine the degree to which the center’s measures corresponded with its stated mission goals. a number of data sources were reviewed including client records of demographic and outcome information. Findings suggest the center maintained records that allow for the evaluation of most of its mission’s goals. There were, however, difficulties with data collection, storage, and retrieval. the present program evaluation found that missing information and lack of follow-up information hindered efforts toward mission evaluation.
An Analysis of the Economic and Institutional Factors Affecting Recovery by Local Governments from Huricanes
This dissertation examines the impact of major hurricanes on changes in GDP for counties in four states – Alabama, Florida, Louisiana, and Texas. The analysis examines the effectiveness of intergovernmental financing for major hurricanes between 2000 and 2014. It also examines whether institutional proximity of the disaster management function to the Governor's Office and the career status of the director affect the speed of recovery from the disaster. The analysis also assesses the impact that a counties's prior experience at dealing with disasters has on the speed of recovery.
An Analysis of the Leadership Development Competency Frameworks of Nontraditional Principal Preparation Programs
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 of research on principal success was promising.
An Analysis of the Pedagogical Advantages Relating to Combined Study of Euphonium and Trombone through the Use of Specific Repertoire
Doubling is defined as playing two instruments. It is becoming increasingly necessary for low brass musicians to double in the course of their careers. Euphoniumists often learn trombone, and trombonists learn euphonium. The instruments share several surface similarities but also differ in many significant ways. Interviews with six professional doublers highlight strategies for learning, teaching, and performing on both trombone and euphonium. Slide and valve technique, adjustment of intonation, tone quality, air usage, repertoire, and skill maintenance are all addressed. Trombone literature comprises a large part of the euphonium repertoire, due to the fact that most trombone pieces can be performed on euphonium. Euphoniumists should avoid playing pieces that require glissandi or extremely loud dynamics to be effective. Euphonium solos are generally too technical to be practical for trombonists to perform. Grøndahl's Concert pour trombone et piano ou orchestre is a standard piece for both instruments. When performing the piece on either instrument, it is helpful to practice the piece on both trombone and euphonium in order to tap into each instrument's strengths.
An Analysis of the Value-altering Effect of Motivating Operations
Motivating operations (MOs) may affect behavior in two ways; A) an MO momentarily alters the frequency of behavior for which a particular consequence has served as reinforcement (evocative-effect) and B) an MO momentarily alters the behavioral effects of the relevant consequence (value-altering effect). Many studies have empirically demonstrated the evocative function of MOs, however, few if any studies have attempted to systematically manipulate and measure the value-altering effect. The focus of this study was to investigate the value-altering effect by measuring choice and response allocation across two alternative tasks. Participants were two female girls diagnosed with autism. During conditioning sessions, experimenters created a history for the children in which clicking on a moving square on a computer monitor produced a small piece of edible. Prior to some conditions, the participants were allowed 5 min of free-access to the edibles, and in other sessions, access to edibles prior to session was restricted. During these sessions, the square was either red or blue depending on the condition type (pre-access or restricted-access). During probe sessions, both colored squares were concurrently available and participants were allowed to allocate their responding to whichever square they chose. One participant preferred the square associated with restricted-access, which may support the notion of the value-altering effect. Difficulties during conditioning sessions interfered with the ability to run sufficient probes with the other participant to evaluate a value-altering effect. Results suggest that the use of these procedures may be useful to differentiate evocative and function-altering effects of MOs.
Analysis of Trace Amounts of Adulterants Found in Powders/Supplements Utilizing Direct Inject, Nanomanipulation, and Mass Spectrometry
The regulations of many food products in the United States have been made and followed very well but unfortunately some products are not put under such rigorous standards as others. This leads to products being sold, that are thought to be healthy, but in reality contain unknown ingredients that may be hazardous to the consumers. With the use of several instrumentations and techniques the detection, characterization and identification of these unknown contaminates can be determined. Both the AZ-100 and the TE2000 inverted microscope were used for visual characterizations, image collection and to help guide the extraction. Direct analyte-probed nanoextraction (DAPNe) technique and nanospray ionization mass spectrometry (NSI-MS) was the technique used for examination and identification of all adulterants. A Raman imaging technique was than introduced and has proven to be a rapid, non-destructive and distinctive way to localize a specific adulterant. By compiling these techniques then applying them to the FDA supplied test samples three major adulterants were detected and identified.
An Analysis of UNT Commuting Patterns
Academic institutions have recently organized to address their campus' greenhouse gas emissions. Along those lines, the University of North Texas (UNT) pledged to minimize the campus' environmental impact, and conducted a transportation survey in May 2009. The analyses confirm that commuting to campus was the second highest source (29%) of UNT's greenhouse gas emissions, following purchased electricity (48%). Students, faculty and staff drive over 89 million miles per year, 84% of which comes from students. Forty‐two percent of student driving trips originate in the primary and secondary core areas surrounding Denton, which are partially served by buses. However, because these core areas are in close proximity to the campus, they contribute only 8% of the total student driving distance. Beyond the Denton core, the inner periphery of Denton County contributes another 22% of driving mileage. Students living in the outer periphery (outside Denton County) contribute the remaining 70% of total driving distance, and carpooling is currently their only alternative.
Analytical Model for Lateral Deflection in Cold-formed Steel Framed Shear Walls with Steel Sheathing
An analytical model for lateral deflection in cold-formed steel shear walls sheathed with steel is developed in this research. The model is based on the four factors: fastener displacement, steel sheet deformation, and hold-down deformation, which are from the effective strip concept and a complexity factor, which accounts for the additional influential factors not considered in the previous three terms. The model uses design equations based on the actual material and mechanical properties of the shear wall. Furthermore, the model accounts for aggressive and conservative designers by predicting deflection at different shear strength degrees.
Analytical Model of Cold-formed Steel Framed Shear Wall with Steel Sheet and Wood-based Sheathing
The cold-formed steel framed shear walls with steel sheets and wood-based sheathing are both code approved lateral force resisting system in light-framed construction. In the United States, the current design approach for cold-formed steel shear walls is capacity-based and developed from full-scale tests. The available design provisions provide nominal shear strength for only limited wall configurations. This research focused on the development of analytical models of cold-formed steel framed shear walls with steel sheet and wood-based sheathing to predict the nominal shear strength of the walls at their ultimate capacity level. Effective strip model was developed to predict the nominal shear strength of cold-formed steel framed steel sheet shear walls. The proposed design approach is based on a tension field action of the sheathing, shear capacity of sheathing-to-framing fastener connections, fastener spacing, wall aspect ratio, and material properties. A total of 142 full scale test data was used to verify the proposed design method and the supporting design equations. The proposed design approach shows consistent agreement with the test results and the AISI published nominal strength values. Simplified nominal strength model was developed to predict the nominal shear strength of cold-formed steel framed wood-based panel shear walls. The nominal shear strength is determined based on the shear capacity of individual sheathing-to-framing connections, wall height, and locations of sheathing-to-framing fasteners. The proposed design approach shows a good agreement with 179 full scale shear wall test data. This analytical method requires some efforts in testing of sheathing-to-framing connections to determine their ultimate shear capacity. However, if appropriate sheathing-to-framing connection capacities are provided, the proposed design method provides designers with an analytical tool to determine the nominal strength of the shear walls without conducting full-scale tests.
An Analytical Perspective of the Developing Aesthetic Concepts in Sergey Prokofiev's Choses en soi, Op. 45
The purpose of this study is to analyze the compositional techniques in Choses en soi op.45, by Sergey Prokofiev, and to explore the new aesthetic concepts he claimed to include in this composition. Through the examination of the compositional elements and discussion of its salient characteristics.
An Analytical Study of Paradox and Structural Dualism in the Music of Ludwig van Beethoven
Beethoven's rich compositional language evokes unique problems that have fueled scholarly dialogue for many years. My analyses focus on two types of paradoxes as central compositional problems in some of Beethoven's symphonic pieces and piano sonatas. My readings of Beethoven's Piano Sonata No. 27 (Op. 90), Symphony No. 4 (Op. 60), and Symphony No. 8 (Op. 93) explore the nature and significance of paradoxical unresolved six-four chords and their impact on tonal structure. I consider formal-tonal paradoxes in Beethoven's Tempest Sonata (Op. 31, No. 2), Ninth Symphony (Op. 125), and Overture die Weihe des Hauses (Op. 124). Movements that evoke formal-tonal paradoxes retain the structural framework of a paradigmatic interrupted structure, but contain unique voice-leading features that superimpose an undivided structure on top of the "residual" interrupted structure. Carl Schachter's observations about "genuine double meaning" and his arguments about the interplay between design and tonal structure in "Either/Or" establish the foundation for my analytical approach to paradox. Timothy Jackson's reading of Brahms' "Immer leiser word meine Schlummer" (Op. 105, No. 2) and Stephen Slottow's "Von einem Kunstler: Shapes in the Clouds" both clarify the methodology employed here. My interpretation of paradox involves more than just a slight contradiction between two Schenkerian readings; it involves fundamentally opposed readings, that both result from valid, logical lines of analytical reasoning. In my view, paradoxes could be considered a central part of Beethoven's persona and philosophy. Beethoven's romantic endeavors and his relationships with mentors suggest that paradoxes might have been central to his bravura. Furthermore, Beethoven's familiarity with the politics of the French Revolution and Shakespearean literature suggest that paradoxes in some pieces (including the Ninth Symphony) could be metaphorical representations of his ideology. However, I do not attempt to explicitly link specific style features to extra-musical ideas. Modern Schenkerian scholars continue to expand …
Analyzing Contingencies of Behavioral and Cultural Selection
A choice paradigm was used to evaluate allocation of interlocking behavior of two groups of two participants between responses having operant consequences only and responses having cultural consequences. In a discrete trial BABABAB design, each participant could select one of three options, which delivered either 3 or 5 points. In B (cultural consequence) conditions, two of the options had additional effects: the 3-point option also added 3 points to the other participant's earnings, and one of the 5-point options also subtracted 5 points from the other participant's earnings. The third option was unchanged in both conditions and delivered 5 points to the participant who selected it. Results indicated that participants in both groups initially frequently produced response combinations that earned 8 points for one or the other individual (and 0 or 3 points for the other), but allocation of responding increasingly changed to combinations that produced 6 points for each individual. This shift in performances away from maximum individual reinforcement towards maximum group reinforcement indicates cultural contingencies did not act in concert with operant contingencies, suggesting they are different mechanisms of selection.
Analyzing Delinquency Among Kurdish Adolescents: a Test of Hirschi’s Social Bonding Theory
This study examines the mediating effect of social bonding on delinquent behavior among Kurdish teens. Major influences to the study of self concept and delinquency based on Hirschi’s social bonding theory are reviewed. The data was collected from a sample of 100 Kurdish teens attending a Gülen affiliated school (Private Çaglayan Murat Anatolian Science High School in Şanlıurfa, Turkey) and 100 Kurdish teens attending a public (non- Gülen) school (The Public High School in Diyarbakır, Turkey). There are two dependent variables for this research project: Involvement in major delinquency and involvement in minor delinquency. The components of social bonding attachment, involvement, commitment, and belief were used as independent variables. Participants’ age ranged between 16 to 18 years. I hypothesize that the relation between the social bonding elements and delinquency should be stronger in the case of Kurdish adolescents who are more attached to conventional Turkish society. Results from binary logistic regression analyses indicate that in the absence of bonding, Kurdish teenagers tend to engage in major and minor delinquent activities. For further exploration and results, the Gülen Movement was examined as an independent variable. Findings suggest a strong relationship between the Gülen Movement and Kurdish adolescents’ probability of involvement in either major or minor delinquent activities. Finally, several directions for future research on Hirschi’s social bonding theory are recommended and some implications are drawn for deterring Kurdish adolescents from becoming involved in delinquent actions.
Analyzing Learning Acquisition and Retention in a WebVR Environment
The primary purpose of this study was to determine if WebVR enhances the knowledge retention regarding mechanical components of high-risk moving machinery, specifically elevators. There were 23 participants divided into a treatment group and comparison group. The treatment group used WebVR to take a virtual elevator machine room tour while the comparison group studied printed images of the same elevator machine room. These alternative activities were conducted prior to a field trip to a real elevator machine room. Gains in knowledge pre to post were measured and compared between the treatment and comparison groups. The research findings showed an overall gain in knowledge for the participants in the elevator bootcamp. More in depth analysis showed the treatment group exhibited significant gains for six of the ten knowledge areas while the comparison group exhibited significant gains in three of the ten targeted knowledge areas. The treatment group gained more knowledge on components higher than eye-level while the comparison group scored better on components that were below eye-level or on the floor. Both groups were seen actively engaged in the field trips. The treatment group members exposed to the virtual reality elevator machine room frequently referred to what they saw in the WebVR while the comparison group did not refer to their printed images while on an actual tour of the elevator machine room. Virtual reality training of this type has the potential to improve basic knowledge and safety trainings. Added, it provides trainings to large numbers of people across the globe who would otherwise not receive such training. This type of training has the potential to save the lives of workers in high risk electro-mechanical spaces and similar settings in different industries.
Analyzing Patterns Within Academic and Legal Definitions: a Qualitative Content Analysis of the Term "Cyberbullying"
Regardless of culture or nation, students today are experiencing bullying via technology. With the rise of technology, this abuse has the ability to become more far-reaching, and more pervasive than ever. These students face oppression, and in some cases severe imbalances of power. Current research is being conducted and laws created based on varying operational and conception definitions of the term "cyberbullying." This study aims to analyze and provide a coherent definition for the term "cyberbullying" as it is used in research and legislation, especially in the context of today's educational environments. The results help shed light on the large variances in the term and suggestions are made to clarify the definition as the field continues to move forward.
Analyzing Tradeoffs between Privacy Concerns and Active Social Media Presence of 18- to 30-Year-Old College Students
This study applied the impression management theory in the context of social networking to investigate the generalized research question of this dissertation which is "Do active social media presence and various privacy concerns influence online behaviors of students on social media?" The results and conclusions are presented via the conduct of three different studies and the summary provides insights and explain the overall contribution of the research. For each study we developed a research model for which data was collected separately for each of these models. Hypotheses of each model were tested by partial least squares- structural equation modeling techniques using SmartPLS 2.0. Our findings confirm the hypotheses and showed that all the predictors positively influence online social networking behaviors. Active social media presence is operationalized as predictors such as SNS stalking awareness, Selective disclosure, desired differential persona, impression motivation, and information trustworthiness. Privacy concerns have been operationalized as SNS privacy awareness, technology awareness. Online behaviors have been operationalized as responsible image and reckless image.
Analyzing Tuberculosis Vulnerability and Variables in Tarrant County
Over 9 million new cases of tuberculosis (TB) were reported worldwide in 2013. While the TB rate is much lower in the US, its uneven distribution and associated explanatory variables require interrogation in order to determine effective strategies for intervention and control. However, paucity of case data at fine geographic scales precludes such research. This research, using zip code level data from 837 confirmed TB cases in Tarrant County obtained from Texas Department of State Health Services, explores and attempts to explain the spatial patterns of TB and related risk markers within a framework of place vulnerability. Readily available census data is then used to characterize the spatial variations in TB risk. The resulting model will enable estimations of the geographic differences in TB case variables using this readily available census data instead of time-consuming and expensive individual data collection.
Analyzing Visitors’ Discourse, Attitudes, Perceptions, and Knowledge Acquisition in an Art Museum Tour After Using a 3D Virtual Environment
The main purpose of this mixed methods research was to explore and analyze visitors’ overall experience while they attended a museum exhibition, and examine how this experience was affected by previously using a virtual 3dimensional representation of the museum itself. The research measured knowledge acquisition in a virtual museum, and compared this knowledge acquired between a virtual museum versus a real one, employing a series of questionnaires, unobtrusive observations, surveys, personal and group interviews related to the exhibition and the artist. A group of twenty-seven undergraduate students in their first semester at the College of Architecture and Design of the Autonomous University of the State of Mexico participated in the research, and were divided in two groups, one of which used a 3D virtual representation previous to the museum visit. Results show that participants who experienced the virtual museum concurred that using it was a positive experience that prepared them to go to the real museum because they knew already what they were going to find. Most of the participants who experienced the virtual museum exhibited an increased activity during their museum visit, either agreeing, being more participative, concurring and showing acceptance, asking questions, or even giving their opinion and analysis, disagreeing with the guide and showing passive rejection. Also participants from this group showed an increase on their correct answers to the knowledge acquisition questionnaires, going from 27% answers responded correctly in the pre-test, to 67% of correct answers after the virtual museum usage. The research attempted to show that experiencing a virtual museum can be similar to the experience in physical museum visits, not only engaging participants to go to the museum, but sometimes even offering a more functional way to deliver content. Results of this research evidence that using a virtual museum creates a positive impact in …
Anatomical and Morphological Responses of Cardiospermum Halicacabum L. (Balloon Vine), to Four Levels of Water Availability
C. halicacabum (Sapindaceae) is an invasive plant that is considered a nuisance species in Texas riparian environments. Little is known of the tolerance of C. halicacabum to flooding and drought; however, this information may provide insight into the characteristics that contribute to C. halicacabum purported invasiveness. C. halicacabum seedlings (n = 92) were exposed to one of four levels of water availability (flooded, saturated, intermediate and dry) over six weeks under greenhouse conditions. Plant performance was affected by water availability; however, there was no effect on survivorship. Flooded and saturated plants exhibited morphological adaptations; producing adventitious roots, hypertrophy, and aerenchyma tissue. Morphological measures, anatomical responses, and patterns of biomass allocation all indicate that C. halicacabum is able to survive periodic inundation, perform in saturation, and establish and thrive on the drier end of a moisture gradient.
Anchor Nodes Placement for Effective Passive Localization
Wireless sensor networks are composed of sensor nodes, which can monitor an environment and observe events of interest. These networks are applied in various fields including but not limited to environmental, industrial and habitat monitoring. In many applications, the exact location of the sensor nodes is unknown after deployment. Localization is a process used to find sensor node's positional coordinates, which is vital information. The localization is generally assisted by anchor nodes that are also sensor nodes but with known locations. Anchor nodes generally are expensive and need to be optimally placed for effective localization. Passive localization is one of the localization techniques where the sensor nodes silently listen to the global events like thunder sounds, seismic waves, lighting, etc. According to previous studies, the ideal location to place anchor nodes was on the perimeter of the sensor network. This may not be the case in passive localization, since the function of anchor nodes here is different than the anchor nodes used in other localization systems. I do extensive studies on positioning anchor nodes for effective localization. Several simulations are run in dense and sparse networks for proper positioning of anchor nodes. I show that, for effective passive localization, the optimal placement of the anchor nodes is at the center of the network in such a way that no three anchor nodes share linearity. The more the non-linearity, the better the localization. The localization for our network design proves better when I place anchor nodes at right angles.
Ancient Musical Ideas Through a Twenty-First Century Lens: An Examination of Tarik O’Regan’s Scattered Rhymes and Its Relationship to Guillaume de Machaut’s Messe de Notre Dame
British composer Tarik Hamilton O’Regan (b. 1978, London) is earning a reputation as an important composer of today. The innovative works of O’Regan are entering the spectrum of professional, educational, and community performing organizations across the United States and Europe. Scattered Rhymes’ intricate melodic, harmonic, and rhythmic relationships with Messe de Notre Dame by Guillaume de Machaut (c.1300-1377) make an examination and comparison of the two works significant. Analyzing Scattered Rhymes by tracing its roots to Guillaume de Machaut’s Messe de Notre Dame, results in a renewed interest in this ancient work and brings prominence to Tarik O’Regan’s modern musical interpretation of ancient ideas. Understanding Scattered Rhymes as a work based on ideas from the fourteenth century in fusion with compositional concepts rooted in the modern era promotes Scattered Rhymes as one that is valuable in the current musical landscape.
And the Stereotype Award Goes to...: A Comparative Analysis of Directors using African American Stereotypes in Film
This study examines African American stereotypes in film. I studied six directors, Kathryn Bigelow, Spike Lee, the Russo Brothers, Ryan Coogler, Tate Taylor, and Dee Rees; and six films Detroit, BlacKkKlansman, Captain America: The Winter Soldier, The Help, and Mudbound. Using the framework of critical race theory and auteur theory, I compared the common themes between the films and directors. The main purpose of my study is to see if White or Black directors predominantly used African American stereotypes. I found that both races of directors rely on stereotypes for different purposes. With Black directors, the stereotype was explained further through character development, while the White directors used the stereotype at face value with no further explanation.
Anger, Forgiveness and Mindfulness: Correlates of Perceived Stress in an LGB Sample
A sexual minority is someone who identifies as lesbian, gay or bisexual (LGB). According to the Minority Stress Model (Meyer, 2003), sexual minorities encounter significant levels of stress due to their minority group status, thus they are more likely to experience perceived stress. Our cross-sectional, correlational study aimed to explore the relationships between forgiveness, mindfulness and anger and how they are related to perceived stress in a convenience sample of ethnically diverse LGB adults. We hypothesized that: 1) anger is positively associated with perceived stress; 2) forgiveness is negatively associated with perceived stress; 3) mindfulness is negatively associated with perceived stress; and 4) anger, forgiveness and mindfulness account for a significant proportion of the variance in perceived stress. 5) The relationship between anger and perceived stress is moderated by forgiveness. 6) The relationship between anger and perceived stress is moderated by mindfulness. Among LGB adults, the extant literature does not address these four variables in conjunction and the relationships between anger, forgiveness, mindfulness and stress has yet to be explored. Various statistical analyses were conducted, including a hierarchical linear regression to test our model. We found that our overall model accounted for 36% of the total variance in perceived stress (F(5, 142) = 17.31, p <.01) with anger (β = .31, t = 3.55, p = .001) and forgiveness (β = -.21, t = -2.56, p < .05) as the significant predictors. Contrary to prediction, forgiveness and mindfulness did not moderate the relationship between anger and perceived stress in our LGB sample. Limitations, strengths, future research and implications are discussed.
Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams
The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
“The Angular Degrees of Freedom” and Other Stories
The preface, " Performing Brain Surgery: The Problematic Nature of Endings in Short Fiction," deals with the many and varied difficulties short story writers encounter when attempting to craft endings. Beginning with Raymond Carver and Flannery O’Connor and moving to my own work, I discuss some of the obscure criteria used to designate a successful ending, as well as the more concrete idea of the ending as a unifying element. Five short stories make up the remainder of this thesis: "In-between Girls," "Crocodile Man," "Surprising Things, Sometimes Amusing," "Good Jewelry," and "The Angular Degrees of Freedom."
Animal Rights and Human Responsibilities: Towards a Relational Capabilities Approach in Animal Ethics
In this thesis, I analyze some of the most important contributions concerning the inclusion of animals in the moral and political sphere. Moving from these positions, I suggest that a meaningful consideration of animals' sentience demands a profound, radical political theory which considers animals as moral patients endowed with specific capabilities whose actualization needs to be allowed and/or promoted. Such theory would take human-animal different types of relationships into account to decide what kind of ethical and political responsibilities humans have towards animals. It would be also based on the assumption that animals' sentience is the necessary and sufficient feature for assigning moral status. I start from the consideration that in the history of political philosophy, most theorists have excluded animals from the realm of justice. I then propose an examination of utilitarianism, capabilities approach, and relational-based theories of animal rights (in particular the works by Kymlicka and Donaldson, and Clare Palmer) and borrow essential elements from each of these approaches to build my theory. I claim that a political theory which attaches high importance to individual capabilities, as well as to the various types of relationships we have with animals, is the most appropriate to tackle the puzzle of human responsibilities to animals.
Animals Alive and Dead
Collection of poems.
Animated Autoethnographies: Using Stop Motion Animation As a Catalyst for Self-acceptance in the Art Classroom
As a doctoral student, I was asked to teach a course based on emerging technologies and postmodern methods of inquiry in the field of art education. The course was titled Issues and Applications of Technology in Art Education and I developed a method of inquiry called animated autoethnography for pre-service art educators while teaching this course. Through this dissertation, I describe, analyze, interrogate, value, contextualize, reflect on, and artistically react to the autoethnographic animated processes of five pre-service art educators who were enrolled in the course. I interviewed the five participants before and after the creation of their animated autoethnographies and incorporated actor-network theory within the theoretical analysis to study how the insights of my students’ autoethnographies related to my own animations and life narratives. The study also examines animated autoethnography as a method of inquiry that may develop or enhance future teaching practices and encourage empathic connections through researching the self. These selected students created animations that accessed significant life moments, personal struggles, and triumphs, and they exhibited unique representations of self. Pre-service art educators can use self-research to create narrative-based short animations and also use socio-emotional learning to encourage the development of empathy within the classroom. I show diverse student examples, compare them to my own animations, and present a new model of inquiry that encourages the development of self by finding place in chaos, loving the unknown, embracing uncertainty, and turning shame into a celebration of life.
Anisotropic Nature of Radially Strained Metal Tubes
Metal pipes are sometimes swaged by a metal cone to enlarge them, which increases the strain in the material. The amount of strain is important because it affects the burst and collapse strength. Burst strength is the amount of internal pressure that a pipe can withstand before failure, while collapse strength is the amount of external pressure that a pipe can withstand before failure. If the burst or collapse strengths are exceeded, the pipe may fracture, causing critical failure. Such an event could cost the owners and their customers millions of dollars in clean up, repair, and lost time, in addition to the potential environmental damage. Therefore, a reliable way of estimating the burst and collapse strength of strained pipe is desired and valuable. The sponsor currently rates strained pipes using the properties of raw steel, because those properties are easily measured (for example, yield strength). In the past, the engineers assumed that the metal would be work-hardened when swaged, so that yield strength would increase. However, swaging introduces anisotropic strain, which may decrease the yield strength. This study measured the yield strength of strained material in the transverse and axial direction and compared them to raw material, to determine the amount of anisotropy. This information will be used to more accurately determine burst and collapse ratings for strained pipes. More accurate ratings mean safer products, which will minimize risk for the sponsor’s customers. Since the strained metal has a higher yield strength than the raw material, using the raw yield strength to calculate burst and collapse ratings is a conservative method. The metal has even higher yield strength after strain aging, which indicates that the stresses are relieved. Even with the 12% anisotropy in the strained and 9% anisotropy in the strain aged specimens, the raw yield strengths are …
Annihilators of Bounded Indecomposable Modules of Vec(R)
The Lie algebra Vec(ℝ) of polynomial vector fields on the line acts naturally on ℂ[]. This action has a one-parameter family of deformations called the tensor density modules F_λ. The bounded indecomposable modules of Vec(ℝ) of length 2 composed of tensor density modules have been classified by Feigin and Fuchs. We present progress towards describing the annihilators of the unique indecomposable extension of F_λ by F_(λ+2) in the non-resonant case λ ≠ -½. We give the intersection of the annihilator and the subalgebra of lowest weight vectors of the universal enveloping algebra (Vec(ℝ)) of Vec(ℝ). This result is found by applying structural descriptions of the lowest weight vectors of (Vec(ℝ)).
An Annotated Bibliography of Selected Music for Saxophone by Charles Ruggiero with an Analysis of Interplay for Soprano Saxophone and Piano
Ruggiero's contributions to contemporary music are noteworthy. They include 27 works written for solo instruments, voice, as well as chamber groups and large ensembles. This study serves as an annotated bibliography of selected works written for saxophone by Charles Ruggiero. They include a piece for large chamber ensemble, Dig: From Tunes My Grandmother Heard (2009), a trio for flute, clarinet, and alto saxophone titled Echoes of "Piano Red" (2006), two saxophone quartets, Dig: JSB 1 (2003), and Three Blues for Saxophone Quartet (1981), two works for alto saxophone and piano, Night Songs and Flights of Fancy (2005), and Strayhorn (1999-2000), one piece for soprano saxophone and piano, Interplay for Soprano Saxophone and Piano (1988), a single movement work for alto saxophone, piano, winds, and percussion, Dance Complusions (2004), one duo for tenor saxophone and percussion, Sizzlesax II (2001), one concerto for soprano saxophone and piano, Concerto for Soprano Saxophone and Orchestra (1995, rev. 1999), and a trio for violin, alto saxophone, and piano, Dances and Other Movements (1983, rev. 1984). In addition, an analysis of Ruggiero's composition Interplay for Soprano Saxophone and Piano offers an insight into the compositional style of the composer.
Anthropology of Aging: Assessment of Old Age Needs and Ethical Issues regarding the Use of Assistive Technologies
The main goal of this research has been to investigate elderly people's needs, perceptions, fears, hopes, and expectation regarding elderly care, including ethical issues linked to assistive technologies. As faith seems to take an important place in how some elders face the aging process, the spiritual dimension was also included. Therefore, the research was conducted among 15 church congregants. Results show that most respondents fear the physical and mental decay due to aging, often resulting in becoming a burden to someone else, along with abandonment and lack of financial resources. Most ethnic groups perceive that other cultures take better care of their elders than their own. Faith seems to offer a great support, as it gives the confidence that divine power will always be there for them even beyond death. The respondents in this research suggest that guidance should be provided in a more structured way, more focus should go on the youth and the elderly, more activities should be organized and practical information should be shared. Regarding the ethical issues of assistive technologies, they are not well informed about their possibilities but acknowledge their potential usefulness, combined with human care. They don't want technology to be too intrusive in their daily life, but they are willing to sacrifice (part of) their privacy for more (medical) safety. There is a general concern that the access to qualitative care would be depending on financial resources.
Anti-bullying Policies And Practices In Texas Middle Schools
For over a decade national attention to bullying in American schools has increased, fueled by publicity about suicides of severely bullied youth. Schools have the charge of maintaining the safety of all students in order to ensure a positive learning environment, but there is little information about what they are doing to prevent bullying. The purpose of this study was to provide information on principals’ perceptions of bullying and what anti-bullying policies, procedures, and programs exist in Texas middle schools. Ninety-nine principals completed an online questionnaire that addressed: 1) their knowledge of district and campus policies concerning bullying; 2) their direct experience with bullying; and, 3) bullying-prevention strategies and training in place in their schools. Principals reported direct experience with all types of bullying included on the questionnaire in their schools, but had a surprisingly small mean of 14.8 verified bullying incidents during the 2010-2011 year. Over 60% felt the level of physical safety in their school was good or very good, but only 35% rated their school’s emotional safety as good or very good. Students, parents, and teachers reported bullying to the majority of principals; however, few schools conducted annual student surveys that could provide accurate information about bullying in their schools. Procedures required by state law were more likely to be in place than those not required, though not all schools complied with all requirements. Fewer than 10% of schools had implemented a formal anti-bullying program. The most commonly cited obstacles to effectively addressing bullying were lack of time to conduct investigations and getting parents to file written reports (40%); however, despite having anti-bullying training, 27% felt limited by the lack of strategies. This study fills a void in the literature by providing a statewide overview of middle school principals’ knowledge of district and campus policies and procedures …
Anticipating Work and Family: Experience, Conflict, and Planning in the Transition to Adulthood
The purpose of this study was to examine the development of work and family plans in young adults, and to clarify the long-term stability, prevalence, and consequences of anticipated work-family conflict. The study utilizes Super’s model of career development and social cognitive career theory, as well as research on current work-family interface, as a framework for understanding the period of anticipating and planning for multiple role integration that occurs between adolescence and adulthood. A sample of 48 male and 52 female college students assessed two years prior completed self-report questionnaires measuring work, marriage, and parenting experience; anticipated work-family conflict; and multiple-role planning. Results of this study suggest that students desire both a career and a family, and recognize potential challenges of a multiple-role lifestyle. Such recognition of anticipated work-family conflict varies by conflict domains and measurement methods, but remains stable over two years. Results also suggest that anticipated work-family conflict does not mediate the relationship between experience and planning; instead, marriage experience predicts planning directly. Implications for the findings are discussed as are suggestions for directions of new research concerning anticipated work-family conflict and planning for multiple roles.
Antigravity
This dissertation contains two parts: Part I, which discusses the elegy of possessive intent, a subgenre of the contemporary American elegy; and Part II, Antigravity, a collection of poems. English elegies have been closely rooted to a specific grief, making the poems closer to occasional poems. The poet—or at least the poet’s speaker—seeks some kind of public consolation for (often) a private loss. The Americanized form does stray from the traditional elegy yet retains some of its characteristics. Some American elegies memorialize failed romantic relationships rather than the dead. In their memorials, these speakers seek a completion for the lack the broken relationship has created in the speakers’ lives. What they can’t replace, they substitute with something personal. As the contemporary poem becomes further removed from tradition, it’s no surprise that the elegy has evolved as well. Discussions of elegies have never ventured into the type of elegy that concerns itself with the sort of unacknowledged loss found in some contemporary American poems of unrequited love. These poems all have speakers who willfully refuse to acknowledge the loss of their love-objects and strive to maintain control/ownership of their beloveds even in the face of rejection.
Antimicrobial and Anti-Platelet Activity in Botanical Extracts of Plants Collected in Northern Thailand
The purpose of my research work was to assess a variety of Northern Thailand plants tissue extracts for antibacterial and anti-platelet aggregation activity. The Minimum Inhibitory Concentration assay method was used to assess antimicrobial activity of plant extracts, while the Zebrafish Platelet Aggregation Assay and the in vitro Whole Human Blood Impedance Aggregation Assay were used to study anti-platelet activity. Forty one plant extracts harvested from the tissues of 26 plants collected from Northern Thailand were assessed. Thirty-four plant extracts were found to have antibacterial activity against the Gram positive bacteria Staphylococcus aureus and/or Bacillus subtilis, while six plant extracts demonstrated activity against the Gram negative bacterium, Escherichia coli. Thirteen plant extracts exhibited anti-platelet aggregation activity better than the positive control. Two crude plant extracts, twigs from Garcinia sp. and twigs from Goniothalamus chilensis were selected for fractionation. Five of the 12 fractions showed anti-platelet activity. Four fractions (two from each plant extract) were selected for further sub-fractionation. Fourteen of 35 sub-fractions were selected for further testing of anti-platelet aggregation activity with 12 sub-fractions demonstrating positive antiplatelet activity. Positive sub-fractions were analyzed using liquid chromatography-mass spectrometry to determine their chemical properties. Three compounds that possessed anti-platelet activity were characterized by nuclear magnetic resonance. The compounds, all isolated from Garcinia sp., were identified as cambogin, isoxanthochymol and guttiferone F.
Antón Arrufat’s Los Siete Contra Tebas: Political Allegory and Anthropological Concepts As Vehicles to Portray Theatrical and Social Conflict
This thesis (i) presents a critical analysis of the political allegory and dramatic elements employed by Antón Arrufat in Los siete contra Tebas in order to comment upon the conflict in Cuban society during and immediately after the Cuban revolution; and (ii) further analyzes that conflict using an anthropological approach in order to establish partial reintegration as an additional final phase in the rites of passage journey.
Antonín Dvořák’s Piano Concerto in G Minor, Opus 33: A Discussion of Musical Intent and Pianistic Effectiveness in Vilém Kurz's Version of the Solo Piano Part
Since its premiere in 1878, Antonín Dvořák’s Piano Concerto in G Minor has been underrated and held in low regard by musicologists, critics, performers and audiences alike. Vilém Kurz (1872-1945), a Czech pianist and pedagogue, revised and reworked the piano solo part to incorporate what he considered to be added brilliance and pianistic effectiveness. However, the revised version has not increased the popularity of the work. In recent decades, this concerto has begun to appear more often in the programs and recordings are currently available, utilizing either the original piano part or Kurz's revision or a combination of both. In order to gain a broader analytical perspective and achieve a more authentic interpretation of the piece, a thorough understanding of the relation between Dvořák’s work and Kurz's revisions is indispensable. This study examines these adaptations and compares them with Dvořák’s scoring in order to gain further insight to Kurz's musical intent and pianistic aims. Examples from all movements are evaluated vis-à-vis the original to determine their purpose and musical validity.
Anxiety, Depression, and Sleep Disorders: Their Relationship and Reduction with Neurotherapy
This study investigated the relationship among anxiety, depression, and sleep disturbances and the treatment of these three disorders through neurotherapy. Research suggests that these conditions commonly co-occur in the general population and that central nervous system (CNS) arousal may play a primary role in the development and maintenance of these disorders. Several recent studies suggested that neurotherapy, a biofeedback-based treatment for CNS dysregulation, might be an effective treatment for comorbid conditions, particularly the ones of interest here, depression, anxiety, and sleep disturbances. This investigation used a clinical case-series design to assess pre/post neurotherapy changes on objective measures of anxiety, depression, and sleep and to determine whether changes in anxiety and depression then predict improvements in sleep quality. Data for 23 participants (10 males) were obtained from files of adults (Mage = 40.22 years, SD = 16.20) who received at least 15 neurotherapy sessions (M = 47.83 sessions, SD = 22.23) the University of North Texas Neurotherapy Lab. Matched pair t-tests revealed that symptoms of sleep disturbance, depression, and anxiety showed significant improvements following neurotherapy. Neurotherapy treatment effect sizes generally ranged from moderate to large (d = .414 - .849). Multiple regression analysis found that changes in self-reported anxiety symptoms, but not depressive symptoms, predicted observed improvements in sleep quality (adjusted R2 = .26). Last, the implications and limitations were discussed in relation to neurotherapy practice and the associated research.
Aphorismen, Capriccio, and Heptameron for Piano Solo By Jürg Baur: a Performer's Guide
The purpose of this dissertation is to give instruction regarding the performance of three important piano works by Jürg Baur (1918-2010). Aphorismen, Capriccio, and Heptameron stand out as his most significant piano works both because of their length and because of their pianistic complexity. Since Baur had a successful career as both teacher and composer during his lifetime, his acclaimed works received many honors in Germany. His works can be performed by intermediate to advanced students. Intermediate students can easily offer simpler pieces like Aphorismen in competitions, while pieces like Capriccio and Heptameron better are suited to a more advanced level. Although some of his compositions are difficult to perform compared with other modern German works, Baur's music is more accessible. In the article, "Auf der Spuren der alten Zeit" Baur is quoted to state that Paul Hindemith and Bela Bartok's music influenced his own compositional ideas. However, although Baur is a modern composer, he didn't write in a totally atonal style, but rather attempted to broaden tonality. While Heptameron is atonal, Aphorismen and Capriccio give the impression of tonality, thus they are more accessible to the audience. I was fortunate enough to study Aphorismen with Baur as well as receiving advice for performance of Capriccio and some movements of Heptameron. Therefore, I gained a primary source of instruction, particularly in regards to pedal markings, rhythmic indications, voice balancing, finger suggestions, articulation markings, and tone of musical expression. In this dissertation, I include my own instructions (accepted by the composer) along with the composer's intentions.
Apology and Forgiveness in Couples
Following a transgression, interpersonal forgiveness is one strategy used to restore harmony between the victim and offender. Research also suggests that forgiveness can promote psychological and physical health. Research has shown that an apology from the offender may facilitate the forgiveness process. The majority of studies suggest that when a victim receives an apology, they experience higher levels of forgiveness toward their offender. The purpose of this thesis was to explore the association between apology and forgiveness in a sample of adults and undergraduate students (N = 803). The results are organized in three sections. First, I found a positive relationship between apology and forgiveness, replicating prior research. Second, I created a new measure of transgression severity, and provided evidence of internal consistency, construct validity, and criterion-related validity for this measure. Third, I tested two variables hypothesized to moderate the association between apology and forgiveness. First, there was some evidence that perceived offender humility moderated the association between simple apology and forgiveness. Offenders who were perceived as being more humble when providing a simple apology were granted more forgiveness than their less humble counterparts. Second, there was some evidence that transgression severity moderated the association between a complete apology and forgiveness, but the effect was in the opposite direction as hypothesized. For individuals who reported a transgression of high severity, there was a stronger association between the completeness of an apology and forgiveness than for individuals who reported a transgression of low severity. I conclude by discussing limitations, areas for future research, and implications for counseling.
Application-Focused Investigation of Monovalent Metal Complexes for Nanoparticle Synthesis
Over the last 20 years, there has occurred an increase in the number, scope, and impact of nanomaterials projects. By leveraging the Surface Plasmon Resonance of metallic nanoparticles for labelling, sensing, and treatment, researchers have demonstrated the versatile utility of these nanomaterials in medicine. The literature provides evidence of use of simple, well-known chemistry for nanomaterials synthesis when the focus is new applications of nanomaterials. A case in point, is the synthesis of metallic nanoparticles, whereby HAuCl4, CuCl2, Cu(acac)2, and AgNO3 are typically employed as nanoparticle precursors. Unfortunately, the use of these precursors limits the number of applications available to these materials - particularly for AuNPs in medicine, where the byproducts of nanoparticle synthesis (most often surface-adsorbed reductants, toxic stabilizers, and growth directors) cause nanoparticles to fail clinical trials. Despite the several thousand publications detailing the advancements in nanoparticle therapeutics, as of 2017, there were only 50 FDA-approved nanoparticle formulations. Less than 10 were based on metallic nanoparticles. This is a problem because many of these nanoparticle therapeutics demonstrate potent cell killing ability and labeling of cells. A solution to this problem may be the use of weakly coordinated, monovalent metal complexes, which require only one electron to reduce them to their metallic state. Further, by designing nanoparticle syntheses around these monovalent complexes, we can employ weaker, environmentally friendly stabilizers. This strategy also forgoes the use of exogenous reducing agents, because the monovalent complexes can be reduced and stabilized by one reagent. Herein we investigate the use of Au(Me2S)Cl, [Cu(MeCN)4]BF4, and AgBF4 with green stabilizers to synthesize a variety of nanomaterials. We find that a range of sizes of spherical particles, as well as a range of sizes of gold triangular prisms can be synthesized by using techniques that follow this strategy.
Application of Adaptive Techniques in Regression Testing for Modern Software Development
In this dissertation we investigate the applicability of different adaptive techniques to improve the effectiveness and efficiency of the regression testing. Initially, we introduce the concept of regression testing. We then perform a literature review of current practices and state-of-the-art regression testing techniques. Finally, we advance the regression testing techniques by performing four empirical studies in which we use different types of information (e.g. user session, source code, code commit, etc.) to investigate the effectiveness of each software metric on fault detection capability for different software environments. In our first empirical study, we show the effectiveness of applying user session information for test case prioritization. In our next study, we apply learning from the previous study, and implement a collaborative filtering recommender system for test case prioritization, which uses user sessions and change history information as input parameter, and return the risk score associated with each component. Results of this study show that our recommender system improves the effectiveness of test prioritization; the performance of our approach was particularly noteworthy when we were under time constraints. We then investigate the merits of multi-objective testing over single objective techniques with a graph-based testing framework. Results of this study indicate that the use of the graph-based technique reduces the algorithm execution time considerably, while being just as effective as the greedy algorithms in terms of fault detection rate. Finally, we apply the knowledge from the previous studies and implement a query answering framework for regression test selection. This framework is built based on a graph database and uses fault history information and test diversity in attempt to select the most effective set of test cases in term of fault detection capability. Our empirical evaluation of this study with four open source programs shows that our approach can be effective and efficient by …
The Application of Common-practice Elements in Modern Music: Examining Examples of Musical Continuity in Selected Piano Works of James R Wintle
The purpose of this dissertation is to analyze the ways in which distinguished American composer James RayWintle (1942-2013) addresses the problem of formal unity and incorporates previous musical styles in his post-tonal compositions. Because post-tonal music lacks many of the pillars that create tonal structure, it can be difficult for a composer to maintain a sense of form when writing in this style. Wintle attempts to circumvent this issue by incorporating common-practice elements, such as formal sections, familiar stylistic gestures, and referential-pitch organization into his works. For this analysis, the author has selected three of Wintle’s piano compositions that best represent his compositional approach and diverse techniques: Album Leaves - A Set of Five Character Pieces for Piano (2001), Scherzino (Street Scenes of Ovada) for Solo Piano (2010), and Four Miniatures for Piano Four Hands (2003). Wintle’s artistic style borrows extensively from Western classical music, encompassing various historical periods and quoting several major composers. Additionally, he incorporates a variety of musical styles into his chamber works and those for solo piano. These range from the dance suites of the French Baroque and Brahmsian-character pieces to American ragtime. This research also describes Wintle’s compositional style and his borrowing of 18th- and 19th-century techniques, forms, and titles, all set in a post-tonal language. The interviews conducted with the composer and his own program notes serve as primary sources, lending an invaluable insight into his works.
Application of Cyclic Polarization of Aluminum 3003 Used in All-Aluminum Microchannel Heat Exchangers
All-aluminum microchannel heat exchangers are designed to significantly reduce refrigerant charge requirements, weight, reduced brazed joints, and decreased potential for leakage by increasing reliability. Al 3003 alloy is corrosion resistant and can be formed, welded, and brazed but the issue with all-aluminum heat exchangers is localized corrosion (pitting) in corrosive environments. Currently, there is no universally accepted corrosion test that all coil manufacturers use to characterize their products. Electrochemical testing method of cyclic polarization was employed in this investigation and relevant parameters including electrolyte corrosive agent and its concentration, electrolyte pH, and applied potential scan rate was varied to find an optimal set of parameters. Results of cyclic polarization of Al 3003 in electrolytes containing various concentrations of NaCl were compared with those of the tests in Sea Water Acidified Accelerated Test (SWAAT) electrolyte and it is shown the SWAAT electrolyte (4.2% sea salt acidified to pH of 2.9) is by far stronger (in terms of corrosivity) than typical 3.5% NaCl solution used in most corrosion testing. Corrosion rates (g/m2yr) of Al 3003 measured in this investigation were comparable to those provided by ISO 9223 standard corresponding to C1 through CX categories. Duration of cyclic polarization test is much shorter than that of SWAAT and results obtained in this test is more reproducible compared to those of SWAAT. Scanning electron microscopy micrographs show typical pit depths of about 50 μm.
An Application of Digital Video Recording and Off-grid Technology to Burrowing Owl Conservation Research
Through this research, engineering students and conservation biologists constructed an off-grid video system for observing western burrowing owls in El Paso, Texas. The burrowing owl has a declining population and their range decreasing, driving scientists' interest to see inside the den for observing critical nesting behavior. Texas Parks and Wildlife Department (TPWD) biologists wanted videos from inside the dark, isolated hillside owl burrows. This research yielded a replicable multi-camera prototype, empowering others to explore applications of engineering and wildlife monitoring. The remote station used an off-the-shelf video recording system, solar panels, charge controller, and lead acid batteries. Four local K-12 science educators participated in system testing at Lake Ray Roberts State Park through the Research Experiences for Teachers (RET, NSF #1132585) program, as well as four undergraduate engineering students as senior design research.
Application of FTIR for Quantification of Alkali in Cement
Alkali-silica reaction (ASR) in cement is a major contributor to failure of cement structures around the world, causing increased repair costs and possible rebuild expenses. Alkali levels are indicative of the potential for ASR and are therefore measured and quantified. A linear correlation relating cement alkali concentration measured by X-ray fluorescence spectroscopy (XRF) and peak ratio measured by Fourier transform infrared spectroscopy (FTIR) is developed. Regression analysis of plots correlating alkali content measured by FTIR absorption band (750 cm-1/923 cm-1) ratio versus equivalent alkali (Na2O)e (%Na2O + 0.658 % K2O) quantified by XRF show linear correlation coefficient, R2, of 0.97. Results of this investigation are discussed in terms of microstructural disorder coefficient Cd which is a reactivity criterion for ASR-susceptible aggregates proposed by Bachiorrini [31]. XRF is a popular technique for alkali quantification but FTIR is faster, safer, and less expensive technique compared to XRF. Portable instrumentation is available for both techniques but FTIR systems are less expensive.
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