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Do contingency-conflicting elements drop out of equivalence classes? Re-testing Sidman's (2000) theory (open access)

Do contingency-conflicting elements drop out of equivalence classes? Re-testing Sidman's (2000) theory

Sidman's (2000) theory of stimulus equivalence states that all positive elements in a reinforcement contingency enter an equivalence class. The theory also states that if an element from an equivalence class conflicts with a programmed reinforcement contingency, the conflicting element will drop out of the equivalence class. Minster et al. (2006) found evidence suggesting that a conflicting element does not drop out of an equivalence class. In an effort to explain maintained accuracy on programmed reinforcement contingencies, the authors seem to suggest that participants will behave in accordance with a particular partitioning of the equivalence class which continues to include the conflicting element. This hypothesis seems to explain their data well, but their particular procedures are not a good test of the notion of "dropping out" due to the pre-establishment of equivalence classes before the conflicting member entered the class. The current experiment first developed unpartitioned equivalence classes and only later exposed participants to reinforcement contingencies that conflicted with pre-established equivalence classes. The results are consistent with the notion that a partition developed such that the conflicting element had dropped out of certain subclasses of the original equivalence class. The notion of a partitioning of an equivalence class seems to …
Date: December 2015
Creator: Silguero, Russell V.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Does Instructional Delivery Method in an Elective Business Class Impact Student Achievement with Respect to Gender, Race and Socio-economic Status in a Selected Texas Public School District? (open access)

Does Instructional Delivery Method in an Elective Business Class Impact Student Achievement with Respect to Gender, Race and Socio-economic Status in a Selected Texas Public School District?

The problem that guided this study was a socio-constructivist view of education via online learning. Based in the extant literature, a deficiency existed that directly correlated online learning closing the academic achievement gap between student populations. In other words, schools invested in technology; however, few empirical data sets existed that established a connection between technology integration and the academic achievement of different student groups. The purpose of this pooled regression analysis study was to determine whether the method of class instruction effected academic achievement gaps between three subpopulations based on gender, race, and SES. Specifically, this study examined whether gender, race, and SES could predict semester grades within and across traditional, blended, and online course instructional methods. The dependent variable for this study was student success in the form of an end-of-unit test grade designed to evaluate student understanding of the curriculum. The independent variables included student gender, ethnicity, and SES. Quantitative data were collected through an analysis of Public Education Information Management System (PEIMS) data and student end-of-unit exam grades. The research suggests one combined interaction, [gender x race] in the traditional learning environment, is statistically significant while several independent interactions are significant. Those independent interactions are TAKS scores, …
Date: December 2015
Creator: Moore, Eldridge D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Dynamic Behaviors of Historical Wrought Iron Truss Bridges – a Field Testing Case Study (open access)

Dynamic Behaviors of Historical Wrought Iron Truss Bridges – a Field Testing Case Study

Civil infrastructure throughout the world serves as main arteries for commerce and transportation, commonly forming the backbone of many societies. Bridges have been and remain a crucial part of the success of these civil networks. However, the crucial elements have been built over centuries and have been subject to generations of use. Many current bridges have outlived their intended service life or have been retrofitted to carry additional loads over their original design. A large number of these historic bridges are still in everyday use and their condition needs to be monitored for public safety. Transportation infrastructure authorities have implemented various inspection and management programs throughout the world, mainly visual inspections. However, careful visual inspections can provide valuable information but it has limitations in that it provides no actual stress-strain information to determine structural soundness. Structural Health Monitoring (SHM) has been a growing area of research as officials need to asses and triage the aging infrastructure with methods that provide measurable response information to determine the health of the structure. A rapid improvement in technology has allowed researchers to start using new sensors and algorithms to understand the structural parameters of tested structures due to known and unknown loading scenarios. …
Date: December 2015
Creator: Hedric, Andrew C.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
An Educational Intervention to Promote Self-management and Professional Socialization in Graduate Nurse Anesthesia Students (open access)

An Educational Intervention to Promote Self-management and Professional Socialization in Graduate Nurse Anesthesia Students

Traditionally, nurse anesthesia educators have utilized prior academic achievement to predict student success. However, research has indicated that prior academic achievement offers an inadequate assessment of student success in graduate healthcare programs with extensive clinical residencies. The educational literature has identified many non-cognitive factors, such as self-efficacy and locus of control, that may provide a more holistic prediction model of student success. An experimental study with pretest-posttest design and stratified random assignment was conducted to evaluate the effectiveness of an educational intervention to promote self-management, professional socialization, and academic achievement among first semester graduate nurse anesthesia students. Participants (N = 66) were demographically similar to the national graduate nurse anesthesia student body, though Hispanics and younger students were a little over-represented in the sample (56% female, 75.8% White, 15.2% Hispanic, 6% Other, 59% ≤ 30-years-old, 67% ≤ 3 years of ICU). The results showed that most graduate anesthesia students had strong self-management and professional socialization characteristics on admission. The results did not support the effectiveness of this educational intervention. Thus, ceiling effect may have accounted in part for statistically non-significant results regarding self-efficacy (p = .190, ω2 = .03), locus of control (p = .137, ω2 = .04), professional socialization …
Date: December 2015
Creator: Maloy, Debra A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Effect of Alloy Composition, Free Volume and Glass Formability on the Corrosion Behavior of Bulk Metallic Glasses (open access)

Effect of Alloy Composition, Free Volume and Glass Formability on the Corrosion Behavior of Bulk Metallic Glasses

Bulk metallic glasses (BMGs) have received significant research interest due to their completely amorphous structure which results in unique structural and functional properties. Absence of grain boundaries and secondary phases in BMGs results in high corrosion resistance in many different environments. Understanding and tailoring the corrosion behavior can be significant for various structural applications in bulk form as well as coatings. In this study, the corrosion behavior of several Zr-based and Fe-Co based BMGs was evaluated to understand the effect of chemistry as well as quenched in free volume on corrosion behavior and mechanisms. Presence of Nb in Zr-based alloys was found to significantly improve corrosion resistance due to the formation of a stable passive oxide. Relaxed glasses showed lower rates compared to the as-cast alloys. This was attributed to lowering of chemical potential from the reduced fraction of free volume. Potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) techniques helped in quantifying the corrosion rate and polarization resistance. The effect of alloy composition was quantified by extensive surface analysis using Raman spectroscopy, energy dispersive x-ray spectroscopy and auger spectroscopy. Pitting intensity was higher in the as-cast glasses than the relaxed glasses. The electrochemical behavior of a Zr-Ti-Cu-Ni-Be bulk metallic glass …
Date: December 2015
Creator: Ayyagari, Venkata Aditya
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effect of Post-exercise Ethanol Consumption on the Acute Hormonal Response to Heavy Resistance Exercise in Women (open access)

The Effect of Post-exercise Ethanol Consumption on the Acute Hormonal Response to Heavy Resistance Exercise in Women

The purpose of this study was to examine the hormonal response to acute ethanol ingestion following a bout of heavy resistance exercise in women. Eight resistance trained women completed two identical acute heavy resistance exercise tasks (AHRET). From 10-20 minutes post-AHRET, participants consumed either a grain ethanol or a placebo beverage. Blood was collected before (PRE) and immediately after the AHRET (IP) and then every 20 minutes for five hours. Blood collected after beverage ingestion was pooled into 3 batches (phases: 20-40 minutes, 60-120 minutes, and 140-300 minutes post-exercise) and analyzed for serum total testosterone (TT), free testosterone (FT), insulin-like growth factor-I (IGF-I), human growth hormone (GH), cortisol (COR), and estradiol (E2) concentrations. Circulating concentrations of TT were significantly greater at P20-40 than at PRE, P60-120, and P140-300. Circulating concentrations of FT were significantly greater at P20-40 than at all other times. Circulating concentrations of GH were significantly greater at IP than at PRE, P60-120, and P140-300. Circulating concentrations of COR were significantly greater at P20-40 than at all other times. Additionally, COR concentrations at P140-300 were significantly lower than at all other times. Circulating concentrations of IGF-1 were significantly greater at P20-40 than at P60-120 and P140-300. Circulating concentrations …
Date: December 2015
Creator: Budnar, Ronald Gene, Jr.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Effects of Child Development Associate Credential System 2.0 on Candidate Success Rates (open access)

Effects of Child Development Associate Credential System 2.0 on Candidate Success Rates

The purpose of this research was to identify the impact of process changes that have been made to the Child Development Associate (CDA) credential, which is a beginning early childhood teacher credential that focuses on competency based standards widely seen as necessary for early childhood teachers to possess. The process in which early childhood teachers receive their credential changed in 2013 with the implementation of CDA credential 2.0. Changes included taking a computerized exam and the implementation of a professional development specialist conducting an on-site classroom observation. In order to determine the impact that CDA 2.0 had on teacher credentialing success rates, a mixed-method sequential design was employed. First, existing data sets of success rates from a national scholarship program were reviewed. Following, interviews with CDA credential seekers were conducted. Findings revealed that while candidate success rates increased for those receiving CDA credentials under the 2.0 system, the actual number of candidates receiving scholarships to pursue the CDA credential through the national scholarship program decreased. Qualitative analysis of the semi-structured interviews indicated that three areas that impacted CDA 2.0 candidate success rates were the professional education programs and instructors, the CDA Exam, and Professional Development Specialists. This is the first …
Date: December 2015
Creator: Davis, Travis J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects of Programmed Reinforcement and Chained Mastery Criteria on Yoga Pose Performance in Two Young Children with Autism (open access)

The Effects of Programmed Reinforcement and Chained Mastery Criteria on Yoga Pose Performance in Two Young Children with Autism

Community exercise can offer many benefits for children, including the opportunity to engage in physical activity and interact with peers in a social setting. Children with autism do not engage in as many community activities as their typical peers. This study examines conditions to teach young children to complete yoga poses to mastery. The effects of prompting, programmed reinforcers, and a chaining criteria were evaluated using a comparison design with two baselines and one intervention condition, replicated across two children with autism. Both children mastered performance of all four targeted yoga poses. The findings are discussed in the context of previous research on the benefits of yoga.
Date: December 2015
Creator: Nguyen, Linda N.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami (open access)

Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami

This study determined the effect of hypoxia on air-breathing onset and physiological and morphological characters in larvae of the air breathing fishes Trichopodus trichopterus and Betta splendens. Larvae were exposed intermittently (12/12 h daily) to 20, 17, and 14 kPa of PO2 from 1 to 40 days post-fertilization. Survival, onset of air breathing, wet body mass, O2, Pcrit were measured every 5 dpf. Hypoxia advanced by 4 days, and delayed by 9 days, the onset of air breathing in Betta and Trichopodus, respectively. Hypoxia increased larval body length, wet mass, and labyrinth organ respiratory surface of Betta, but did not affect these factors in Trichopodus. Hypoxic exposure increased O2 by 50-100% at each day throughout larval development in Betta, but had no effect on larval Trichopodus. Hypoxia decreased Pcrit in Betta by 37%, but increased Pcrit in Trichopodus by 70%. Larval Betta reared in hypoxia showed a modified heart rate:opercular rate ratio (3:1 to 2:1), but these changes did not occur in Trichopodus. Compared to Betta, the blood of Trichopodus had a higher P50 and much smaller Bohr and Root effects. These interspecific differences are likely due to ecophysiological differences: Betta is a non- obligatory air-breather after 36 dpf with …
Date: December 2015
Creator: Mendez Sanchez, Jose Fernando
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Evaluating a Sustainable Community Development Initiative Among the Lakota People on the Pine Ridge Indian Reservation (open access)

Evaluating a Sustainable Community Development Initiative Among the Lakota People on the Pine Ridge Indian Reservation

This thesis details my applied thesis project and experience in the evaluation of a workforce development through sustainable construction program. It describes the need of my client, Sweet Grass Consulting and their contractual partner, the Thunder Valley Community Development Corporation, in the evaluation of Thunder Valley CDC's Workforce Development through Sustainable Construction Program. My role involved the development of an extensive evaluation package for this program and data analysis of evaluation materials to support Thunder Valley CDC's grant-funded Workforce Development Program. I place the efforts of Thunder Valley CDC in the context of their community, the Pine Ridge Reservation of the Lakota People, and within an historical and contemporary context to highlight the implications of the efforts of Thunder Valley CDC. Using the theoretical frameworks of cultural revitalization and community economic development, I attempt to highlight two important components of Thunder Valley CDC's community development efforts - cultural revitalization for social healing, and development that emphasizes social, community and individual well-being. Thunder Valley CDC's Workforce Development through Sustainable Construction Program is still in its early stages, and so this first year of implementation very much represented a pilot phase. However, while specific successes are difficult to measure at this point, …
Date: December 2015
Creator: Mosman, Sarah A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Examination of Sexual Differences in the Acute Effects of Haloperidol on Licking (open access)

Examination of Sexual Differences in the Acute Effects of Haloperidol on Licking

Schizophrenia is a debilitating psychiatric condition affecting almost one percent of the US population. Typical antipsychotics (e.g., haloperidol) have been in use for several decades and are generally very effective in treating the emotional and cognitive effects of schizophrenia, but are used as the last line of treatment due to their severe extrapyramidal motor side effects under chronic exposure. The present study was conducted to investigate the role of sex in determining the oromotor side effects of typical antipsychotics via measuring different behavioral dimensions of male and female Sprague-Dawley rats licking sucrose after haloperidol treatment. The results showed a stronger sensitivity in female rats than male rats within total licking responses and inter-lick intervals. The present results suggest closer attention needs to be paid to the role that sexual hormones play in the motor slowing and behavior-reducing effects of antipsychotics.
Date: December 2015
Creator: Shoemaker, Danton L.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Expertise Revisited: Reflecting on the Intersection of Science and Democracy in the Case of Fracking (open access)

Expertise Revisited: Reflecting on the Intersection of Science and Democracy in the Case of Fracking

This dissertation aims to explain the conditions under which expertise can undermine democratic decision making. I argue that the root of the conflict between expertise and democracy lies in what I call insufficiently “representative” expertise – that is forms of scientific research that are not relevant to the policy questions at hand and that fail to make visible their hidden values dimensions. I claim that the scholarly literature on the problem of expertise fails to recognize and address the issue correctly, because it does not open the black box of scientific methodologies. I maintain that only by making sense of the methodological choices of experts in the context of policy making can we determine the relevance of research and reveal the hidden socio-political values and consequences. Using the case of natural gas fracking, I demonstrate how expert contributions – even though epistemically sound – can muddle democratic policy processes. I present four case studies from controversies about fracking to show how to contextualize scientific methodologies in the pertinent political process. I argue that the common problem across all case studies is the failure of expertise to sufficiently represent stakeholders’ problems and concerns. In this context, “representation” has three criteria: (1) …
Date: December 2015
Creator: Ahmadi, Mahdi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Exploring Student Learning on a Short-term, Faculty-led Study Abroad Course Through a Student Development Lens (open access)

Exploring Student Learning on a Short-term, Faculty-led Study Abroad Course Through a Student Development Lens

Embarking on a study abroad experience is thought to be a transformational experience for students, and previous researchers have tended to find that the potential benefits of study abroad experiences, including greater conceptual and behavioral intercultural competence, are greater with longer periods abroad. The purpose of this study was to create an intentional learning experience for students who embarked on a short-term study abroad in rural areas of China and to apply faculty intervention of a student development approach to student learning to create a high-impact learning environment for students centered on a service-learning project. This qualitative study gathered primary data from students and instructors during the course through a collection of observation and field notes, student journals, pre- and post-construct tests, and final presentation. Follow-up interviews were conducted 10 months after course completion. Six students participated in this course and study who were from a variety of disciplines and classifications. Five students were female; one was male. Four students were undergraduates; two were graduate students. Student ethnicities included three Caucasians and African American, along with two international students from Mexico and Iran. Key outcomes of this study were that when short-term study abroad faculty members applied creative interventions, students …
Date: December 2015
Creator: Garcia, Hope F.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Exploring the Dual-natured Impact of Digital Technology on Student-classroom Engagement in a Texas Public High School (open access)

Exploring the Dual-natured Impact of Digital Technology on Student-classroom Engagement in a Texas Public High School

The past decade has become rife with an eagerness to integrate new digital technology into teaching. While there have been decades of research done on the importance of curriculum and pedagogy on student engagement, findings of actual technology integration are scarce. Moreover, what does it take to engage students in classroom activities and lessons when technology is introduced? The purpose of this study was to explore how digital technology, when integrated into classroom teaching and activities, impacted the students-classroom engagement based on the interim-cognitive, meta-cognitive, motivational, and behavioral markers. This was explored in a Texas public high school across the four core classes (English, Math, Science, and Social Studies. Data was collected in the form of observational field notes, transcripts of recorded lessons, and Likert-scaled surveys. Thematic analysis was used in analyzing qualitative data, Pearson’s correlation of those components found by factor analysis verified three of the five themes identified from the thematic analysis with statistical significance. The findings suggest that mere use of technology does not have a profound impact on student engagement. Instead, technology tends to amplify the existing classroom culture and social norms agreed upon between the teacher and their students. Texas teachers and students are also …
Date: December 2015
Creator: Ayers, Joseph J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Exploring the Effectiveness of Curriculum Provided Through Transmedia Books for Increasing Students’ Knowledge and Interest in Science (open access)

Exploring the Effectiveness of Curriculum Provided Through Transmedia Books for Increasing Students’ Knowledge and Interest in Science

Transmedia books are new and emerging technologies which are beginning to be used in current classrooms. Transmedia books are a traditional printed book that uses multiple media though the use of Quick Response (QR) codes and augmented reality (AR) triggers to access web-based technology. Using the transmedia book Skills That Engage Me students in kindergarten through second grade engage in curriculum designed to introduce science skills and careers. Using the modified Draw-a-Scientist Test (mDAST), observations and interviews, researchers analyzed pre and post data to describe changes students have about science and scientists. Future study may include the development and validation of a new instrument, Draw a Science Student, and examining the mDAST checklist with the intention of updating the parameters of what is considered positive and negative in relationship with work a scientist conducts.
Date: December 2015
Creator: Ponners, Pamela Jones
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Fashioning Society in Eighteenth-century British Jamaica (open access)

Fashioning Society in Eighteenth-century British Jamaica

White women who inhabited the West Indies in the eighteenth century fascinated the metropole. In popular prints, novels, and serial publications, these women appeared to stray from “proper” British societal norms. Inhabiting a space dominated by a tropical climate and the presence of a large enslaved African population opened white women to censure. Almost from the moment of colonial encounter, they were perceived not as proper British women but as an imperial “other,” inhabiting a middle space between the ideal woman and the supposed indigenous “savage.” Furthermore, white women seemed to be lacking the sensibility prized in eighteenth-century England. However, the correspondence that survives from white women in Jamaica reveals the language of sensibility. “Creolized” in this imperial landscape, sensibility extended beyond written words to the material objects exchanged during their tenure on these sugar plantations. Although many women who lived in the Caribbean island of Jamaica might have fit the model, extant writings from Ann Brodbelt, Sarah Dwarris, Margaret and Mary Cowper, Lady Maria Nugent, and Ann Appleton Storrow, show a longing to remain connected with metropolitan society and their loved ones separated by the Atlantic. This sensibility and awareness of metropolitan material culture masked a lack of empathy …
Date: December 2015
Creator: Northrop, Chloe Aubra
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Female Friendship Films: A Post-Feminist Examination of Representations of Women in the Fashion Industry (open access)

Female Friendship Films: A Post-Feminist Examination of Representations of Women in the Fashion Industry

This thesis focuses on three fashion industry themed female friendship films: Pret-a-Porter/Ready to Wear (1994) by Robert Altman, The Devil Wears Prada (2006) by David Frankel, and The September Issue (2009) by R.J. Cutler. Female interpersonal relationships are complex – women often work to motivate, encourage and transform one another but can just as easily use tactics like intimidation, manipulation, and exploitation in order to save their own jobs and reputations. Through the lens of post-feminist theory, this thesis examines significant female interpersonal relationships in each film to illustrate how femininity is constructed and driven by consumer culture in the fashion industry themed films.
Date: December 2015
Creator: Geloğullari, Gülin
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Foreign Sponsorship and the Development of Rebel Parties (open access)

Foreign Sponsorship and the Development of Rebel Parties

This dissertation examines the emergence, survival, performance, and national impact of rebel parties following negotiated settlements. Building on a growing literature examining the environmental and organizational factors affecting insurgent-to-party transformations, this dissertation asks why some insurgent organizations thrive as political parties in post-conflict environments and others fail to make such a transformation. I propose that foreign actors play a pivotal role in the formation of what I call “protégé parties,” which are better equipped to make the transformation into political parties than other rebel groups. Further, different kinds of sponsors have varying effects on transformation. Empirical analysis supports these propositions, finding that protégé parties with authoritarian sponsorship are better equipped to develop than those backed by democracies or no one.
Date: December 2015
Creator: Marshall, Michael C.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Form in Popular Song, 1990-2009 (open access)

Form in Popular Song, 1990-2009

Through an examination of 402 songs that charted in the top 20 of the Billboard year-end charts between the years 1990 and 2009, this dissertation builds upon previous research in form of popular song by addressing the following questions: 1) How might formal sections be identified through melody, harmony, rhythm, instrumentation, and text? 2) How do these sections function and relate to one another and to the song as a whole? 3) How do these sections, and the resulting formal structures, relate to what has been described by previous theorists as normative? 4) What new norms and trends can be observed in popular song forms since 1990? Although many popular songs since 1990 do follow well-established forms, some songwriters and producers change and vary these forms. AAA strophic form, AABA form, Verse-Chorus form, Verse-Chorus with Prechorus and/or Postchorus sections, Verse-Chorus-Bridge form, “Other, with a Chorus” and “Other, without a Chorus” forms are addressed. An increasing number of the songs in each of the above listed forms are based on a repeating harmonic progression or no harmonic progression at all. In such songs, the traditional method of identifying sections and section-functions through harmonic analysis is less useful as an analytical tool, …
Date: December 2015
Creator: Ensign, Jeffrey S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

The Forty-fifth Illinois Volunteer Infantry Regiment: the Washburne Lead Mine Regiment in the Civil War

Access: Use of this item is restricted to the UNT Community
Of the roughly 3,500 volunteer regiments and batteries organized by the Union army during the American Civil War, only a small fraction has been studied in any scholarly depth. Among those not yet examined by historians was one that typified the western armies commanded by the two greatest Federal generals, Ulysses S. Grant and William T. Sherman. The Forty-fifth Illinois Volunteer Infantry was at Fort Donelson and Shiloh with Grant in 1862, with Grant and Sherman during the long Vicksburg campaign of 1862 and 1863, and with Sherman in the Meridian, Atlanta, Savannah, and Carolinas campaigns in the second half of the war. These Illinois men fought in several of the most important engagements in the western theater of the war and, in the spring of 1865, were present when the last important Confederate army in the east surrendered. The Forty-fifth was also well connected in western politics. Its unofficial name was the “Washburne Lead Mine Regiment,” in honor of U.S Representative Elihu B. Washburne, who used his contacts and influences to arm the regiment with the best weapons and equipment available early in the war. (The Lead Mine designation referred to the mining industry in northern Illinois.) In addition, …
Date: December 2015
Creator: Mack, Thomas B., 1965-
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Fractional Calculus and Dynamic Approach to Complexity (open access)

Fractional Calculus and Dynamic Approach to Complexity

Fractional calculus enables the possibility of using real number powers or complex number powers of the differentiation operator. The fundamental connection between fractional calculus and subordination processes is explored and affords a physical interpretation for a fractional trajectory, that being an average over an ensemble of stochastic trajectories. With an ensemble average perspective, the explanation of the behavior of fractional chaotic systems changes dramatically. Before now what has been interpreted as intrinsic friction is actually a form of non-Markovian dissipation that automatically arises from adopting the fractional calculus, is shown to be a manifestation of decorrelations between trajectories. Nonlinear Langevin equation describes the mean field of a finite size complex network at criticality. Critical phenomena and temporal complexity are two very important issues of modern nonlinear dynamics and the link between them found by the author can significantly improve the understanding behavior of dynamical systems at criticality. The subject of temporal complexity addresses the challenging and especially helpful in addressing fundamental physical science issues beyond the limits of reductionism.
Date: December 2015
Creator: Beig, Mirza Tanweer Ahmad
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Fundamental Studies of Copper Corrosion in Interconnect Fabrication Process and Spectroscopic Investigation of Low-k Structures (open access)

Fundamental Studies of Copper Corrosion in Interconnect Fabrication Process and Spectroscopic Investigation of Low-k Structures

In the first part of this dissertation, copper bimetallic corrosion and its inhibition in cleaning processes involved in interconnect fabrication is explored. In microelectronics fabrication, post chemical mechanical polishing (CMP) cleaning is required to remove organic contaminants and particles left on copper interconnects after the CMP process. Use of cleaning solutions, however, causes serious reliability issues due to corrosion and recession of the interconnects. In this study, different azole compounds are explored and pyrazole is found out to be a potentially superior Cu corrosion inhibitor, compared to the most widely used benzotriazole (BTA), for tetramethyl ammonium hydroxide (TMAH)-based post CMP cleaning solutions at pH 14. Micropattern corrosion screening results and electrochemical impedance spectroscopy (EIS) revealed that 1 mM Pyrazole in 8 wt% TMAH solution inhibits Cu corrosion more effectively than 10 mM benzotriazole (BTA) under same conditions. Moreover, water contact angle measurement results also showed that Pyrazole-treated Cu surfaces are relatively hydrophilic compared to those treated with BTA/TMAH. X-ray photoelectron spectroscopy (XPS) analysis supports Cu-Pyrazole complex formation on the Cu surface. Overall Cu corrosion rate in TMAH-based highly alkaline post CMP cleaning solution is shown to be considerably reduced to less than 1Å/min by addition of 1 mM Pyrazole. In …
Date: December 2015
Creator: Goswami, Arindom
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Ghost Machine (open access)

Ghost Machine

This thesis consists of a collection of poems. By virtue of its content and arrangement, the collection ruminates on and attempts to work through the problem of corporeality and bodily experience: the anxieties surrounding illness, mortality, and the physicality of contemporary life. This collection explores the tension inherent in the mind/body duality and, rather than prescribing solutions, offers multiple avenues and perspectives through which to view bodily experience, as well as how that experience affects an individual’s identity, agency, and sense of self.
Date: December 2015
Creator: Whitby, Bess
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Guidelines for Greening (Renovation) of Existing Homes (open access)

Guidelines for Greening (Renovation) of Existing Homes

This Thesis is aimed at evaluating the options of renovation for an existing residential building to make it more energy efficient. The various aspects in the basic structures of residential homes are discussed in order to help the user identify the areas of the house for which renovation is required to improve the energy efficiency of the building. These aspects include doors, roof and wall in addition to various systems of electrical wiring, mechanical systems of ventilation, heating and cooling and plumbing systems for the efficient flow of water throughout the house. The renovation options have been described in detail to provide as many possibilities to the user as possible. The building taken for renovation is a 1953 suburban home which has been awarded the honor of being the first building to be labeled as Zero Energy Home in its vicinity. This has made the home so efficient that its expenditure of energy has become equivalent to its energy generation, therefore, cancelling each other out and creating an estimate of zero energy.
Date: December 2015
Creator: Shaikh, Gilman Yusuf
Object Type: Thesis or Dissertation
System: The UNT Digital Library