States

Adult Attachment Patterns, Mental Representation of Self, and Faith: Mediators of Childhood Trauma and Affect-Behavior Regulations in Adulthood (open access)

Adult Attachment Patterns, Mental Representation of Self, and Faith: Mediators of Childhood Trauma and Affect-Behavior Regulations in Adulthood

The purpose of this study was to investigate psychological mechanism by which four intra- and inter-personal characteristics of an individual (anxious and avoidant adult attachment patterns, images of self, and religious faith) mediate the relationship between childhood trauma and each of three affect-behavior regulation problems in adulthood (symptoms of depression, disordered eating behaviors, and substance abuse). A total of 401 college student participants completed a packet of 18 surveys including 10 surveys used in the present study. Structural equation modeling was used to test each of three hypothesized structural models (Depression, Eating Disturbances, and Substance Abuse). A series of multi-group analyses conducted to test if each of three hypothesized models is invariant across gender indicated no significant difference between females and males. Thus, the data were combined across gender to test for mediated effects in each of three hypothesized models. The results indicated: (a) for the hypothesized model for depression, anxious attachment patterns, avoidant attachment patterns, and negative self-images, but not religious faith, fully mediated the relationship between childhood trauma and symptoms of depression; (b) for the model for eating disturbances, anxious attachment and negative images of self, but not avoidant attachment and religious faith, fully mediated the association between …
Date: December 2010
Creator: Han, GiBaeg
System: The UNT Digital Library
Alberto Ginastera and the Guitar Chord: An Analytical Study (open access)

Alberto Ginastera and the Guitar Chord: An Analytical Study

The guitar chord (a sonority based on the open strings of the guitar) is one of Alberto Ginastera's compositional trademarks. The use of the guitar chord expands throughout forty years, creating a common link between different compositional stages and techniques. Chapters I and II provide the historical and technical background on Ginastera's life, oeuvre and scholar research. Chapter IV explores the origins of the guitar chord and compares it to similar specific sonorities used by different composers to express extra-musical ideas. Chapter V discusses Ginastera's initial uses and modifications of the guitar chord. Chapter VI explores the use of the guitar chord as a referential sonority based on Variaciones Concertantes, Op. 23: I-II, examining vertical (subsets) and horizontal (derivation of motives) aspects. Chapter VII explores uses of trichords and hexachords derived from the guitar chord in the Sonata for Guitar Op. 47.
Date: December 2010
Creator: Gaviria, Carlos A.
System: The UNT Digital Library
Alignment of Middle School Core TEKS with Visual Arts TEKS (open access)

Alignment of Middle School Core TEKS with Visual Arts TEKS

This descriptive study uses a qualitative, content analysis to examine the middle school visual arts and core Texas Essential Knowledge and Skills (TEKS) to determine the potential common learning activities that can be aligned between the two. By performing an alignment of the potential common learning activities present in the middle school visual art TEKS and the middle school core TEKS, I demonstrate that there is a foundation for curriculum integration in the Texas middle school visual arts classroom.
Date: December 2010
Creator: Hartman, Jennifer
System: The UNT Digital Library
Baseball in the Digital Age: The Role of Online and Mobile Content in Major League Baseball's Media Product Portfolio (open access)

Baseball in the Digital Age: The Role of Online and Mobile Content in Major League Baseball's Media Product Portfolio

This case study evaluated Major League Baseball's (MLB) media product portfolio to identify how broadcast revenues have evolved over the past decade. This research looked back across baseball's long, dysfunctional history with broadcasters in order to recognize the significance of its ambitious use of online content. While MLB had failed to fully utilize the potential of broadcasting, the league's aggressive online strategy through its Advanced Media (MLBAM) division made it the industry leader in broadcasting live streaming sports video. MLBAM expanded its online streaming video to mobile phones and iPad, further expanding the distribution of its content. This research compared MLBAM revenue to traditional broadcast revenue while analyzing the online division's role in promoting the MLB brand. This case study concluded that while MLBAM had made a number of groundbreaking developments, the league could still improve its use of embedded, shared video clips, archived footage and international marketing in order to further extend the brand equity of the MLB, its thirty individual brands and its media product portfolio.
Date: December 2010
Creator: Hutton, Brian P.
System: The UNT Digital Library
Benefits and Costs of Social Interactions Among Firefighters (open access)

Benefits and Costs of Social Interactions Among Firefighters

Despite high levels of exposure, firefighter posttraumatic stress disorder (PTSD) rates are unclear. Likewise, questions remain regarding how social interactions and beliefs about emotion might interact to influence PTSD in firefighters. In this study, U.S. urban firefighters (N = 225) completed measures of social support, negative social interactions, and fear of emotion which were then used via regression analyses to predict PTSD symptoms. Each independent variable predicted PTSD beyond variance accounted for by demographic variables. Additionally, fear of emotion emerged as the strongest individual predictor of PTSD and a moderator of the relation between social interactions and PTSD symptoms. These findings emphasize the importance of beliefs about emotion; both in how these beliefs might influence the expression of PTSD symptoms, and in how the social networks of trauma survivors might buffer distress.
Date: December 2010
Creator: Farnsworth, Jacob
System: The UNT Digital Library
A-Bu-GE: A Composition for Organ and Percussion (open access)

A-Bu-GE: A Composition for Organ and Percussion

Keyphrases describe a document in a coherent and simple way, giving the prospective reader a way to quickly determine whether the document satisfies their information needs. The pervasion of huge amount of information on Web, with only a small amount of documents have keyphrases extracted, there is a definite need to discover automatic keyphrase extraction systems. Typically, a document written by human develops around one or more general concepts or sub-concepts. These concepts or sub-concepts should be structured and semantically related with each other, so that they can form the meaningful representation of a document. Considering the fact, the phrases or concepts in a document are related to each other, a new approach for keyphrase extraction is introduced that exploits the semantic relations in the document. For measuring the semantic relations between concepts or sub-concepts in the document, I present a comprehensive study aimed at using collaboratively constructed semantic resources like Wikipedia and its link structure. In particular, I introduce a graph-based keyphrase extraction system that exploits the semantic relations in the document and features such as term frequency. I evaluated the proposed system using novel measures and the results obtained compare favorably with previously published results on established benchmarks.
Date: December 2010
Creator: Kim, Chol-Ho
System: The UNT Digital Library
A Case Study of the Impact of the Middle School Data Coach on Teacher Use of Educational Test Data to Change Instruction (open access)

A Case Study of the Impact of the Middle School Data Coach on Teacher Use of Educational Test Data to Change Instruction

With the advent of No Child Left Behind (NCLB) legislation in 2002 and its attendant increases in accountability pressure, many districts and schools currently embrace data analysis as an essential part of the instructional decision making process. In their attempts to overcome low achievement on state-mandated tests, some districts have begun employing data coaches. The study reported here, which was set in three middle schools in a northeast Texas school district, assessed the influence of the campus data coach on a middle school mathematics teachers' use of analyzed data to make instructional decisions. It also examined the extent to which the Data Coach/teacher relationship resolved teacher concerns about data-driven decision making. Phenomenological interviews with data coaches were guided by Seidman's (2006) three-series interview. Measurement of teacher use of data to make decisions was based on the concerns-based adoption model's levels of use interview protocol, stages of concern questionnaire, and innovation configuration map. By the end of one school year, two out of the three teachers never used data to make instructional decisions, although the non-users both had moved closer toward employing the innovation in their classroom. Data indicated all teachers were aware of the innovation, but all three ended the …
Date: December 2010
Creator: Hill, Rachelle Phelps
System: The UNT Digital Library
Chirped-Pulse Fourier Transform Microwave Spectroscopy of Fluoroiodoacetonitrile and Chloropentafluoroacetone (open access)

Chirped-Pulse Fourier Transform Microwave Spectroscopy of Fluoroiodoacetonitrile and Chloropentafluoroacetone

This work focuses on finding the complete iodine and nitrogen nuclear electric quadrupole coupling tensors for fluoroiodoacetonitrile using chirped-pulse Fourier transform microwave spectroscopy. Fluoroiodoacetonitrile contains two hyperfine nuclei, iodine (I=5/2) and nitrogen (I=1) and the spectra were observed with great resolution. A total of 499 transitions were observed for this molecule. The a, b and c rotational constants were obtained. A study of chloropentafluoroacetone was also done using chirped-pulse Fourier transform microwave spectroscopy. The two chlorine isotopes for this molecule, Cl-35 and Cl-37 were observed and 326 and 170 transitions were recorded, respectively.
Date: December 2010
Creator: Kadiwar, Gautam
System: The UNT Digital Library
College Success for all Students: An Investigation of Early Warning Indicators of College Readiness (open access)

College Success for all Students: An Investigation of Early Warning Indicators of College Readiness

The purpose of this quantitative study was to determine early warning indicators of college readiness among early college high school students at selected Texas institutions of higher education. Participants in this study included 134 of the class of 2010 from two early college high schools. The graduates were 86% Hispanic, 8% African American, 3% White, 2% Asian, 1% American Indian and 72% economically disadvantaged. A causal-comparative research design using multiple regression analysis of the data collected revealed that each one unit increase in world history was associated with a .470 (p < .05) increase in college GPA, while each one unit increase in Algebra I was associated with a .202 (p < .05) increase. Therefore, student grades in high school Algebra I and world history were the strongest statistically significant indicators that a student will maintain a 2.5 college GPA during the first year of college. According to the early warning indicators, students who maintain a grade of A or B in Algebra I are 10 times more likely to be college ready while having a 78% chance of maintaining a 2.5 or better in college courses. Further, the findings from this study found no significant relationship between TAKS assessment, …
Date: December 2010
Creator: Davis, Denise
System: The UNT Digital Library
Combining of Korean Traditional Performance and Recent German Techniques in Isang Yun's Kontraste: Zwei Stücke für Violine Solo (1987) (open access)

Combining of Korean Traditional Performance and Recent German Techniques in Isang Yun's Kontraste: Zwei Stücke für Violine Solo (1987)

Isang Yun (1917-1995) embraced a masterful combination of two elements derived from his life: his Korean cultural upbringing and Western musical traditions. This dissertation explores Yun's distinctive style through an analysis of his Kontraste: Zwei Stücke für Violine Solo. Following the introduction (Chapter 1), Chapter 2 contains a brief biography of Isang Yun, and explores the compositions of his Korean period (1917-1955) and his European period (1956-1995). It also discusses how Yun's musical styles changed during these two periods as a result of important life events and due to cultural and political influences. Chapter 3 examines Korean instruments such as Kayakem, Hae-Kem, and Pak; discusses Nonghyun (traditional string techniques of ornamentation in Korean music); and introduces Korean performance techniques. This chapter also provides explanations of these concepts, illustrated through various examples. A subsequent discussion illuminates Yin-Yang theory and Jeong-Jung-Dong, both elements of Taoist philosophy that influenced Yun's compositional style. This is followed by explanations of Hauptton and Umspielung, two compositional techniques that Yun developed and employed in Kontraste. Yun created the idea of Hauptton to reflect the Korean traditional concept of a single note. He used the term Umspielung ("playing around" in German) to describe his interpretation of the four …
Date: December 2010
Creator: Kim, Hyo Jung
System: The UNT Digital Library
Correlates of Video Game Addiction (open access)

Correlates of Video Game Addiction

Video game addiction often leads to a tremendous burden on those afflicted with the condition, draining their time, resources, and life away until they have nothing left. To further elucidate the problem of video game addiction, the current research examines the level of video game addiction of 111 participants, along with their motivation for their addictive behaviors, the quality of life of addicted individuals, and possible relations between video game addiction and other forms of addiction. Results of the current research indicate a correlation between addictive video game use and depression, alcohol use, a desire for escapism, a need for social interaction, and lack of self-control. The results of a multiple regression indicate that, amongst the various research factors, depression is the factor with the most significant link to addictive video game use, implying a dangerous correlation between mental health and an addictive behavior that some erroneously disqualify as a true addiction.
Date: December 2010
Creator: Langley, Alex
System: The UNT Digital Library
Critical Discussion of Pleroma: A Digital Drama and Its Relevance to Tragic Form in Music (open access)

Critical Discussion of Pleroma: A Digital Drama and Its Relevance to Tragic Form in Music

Pleroma is a digital drama: a work composed of digital animation combined with electroacoustic music, presenting an original dramatic narrative. Pleroma's dramatic elements evoke both the classical form of tragedy and the concept of perceptual paradox. A structural overview of the drama and its characters and a plot synopsis are given to provide context for the critical discussion. Analytical descriptions of Beethoven's Coriolan Overture Op.62 and Mahler's Symphony No. 9 are provided to give background on tragic form and Platonic allegory in music. An investigation into the elements discussed in the analysis of the instrumental works reveals several layers of possible interpretation in Pleroma. Dramatic elements allow for tragic narratives to be constructed, but they are complemented by character associations formed by pitch relationships, stylistic juxtapositions, and instrumentation. A copy of the dramatic text is included to supplement the multimedia production.
Date: December 2010
Creator: Lucas, Stephen, 1985-
System: The UNT Digital Library
Culture and Self-Representation in the Este Court: Ercole Strozzi's Funeral Elegy of Eleonora of Aragon, a Text, Translation, and Commentary. (open access)

Culture and Self-Representation in the Este Court: Ercole Strozzi's Funeral Elegy of Eleonora of Aragon, a Text, Translation, and Commentary.

This dissertation presents a previously unedited text by one of the most distinguished- yet neglected-Latin writers of the Italian Renaissance, Ercole Strozzi (1471-1508), a poet and administrator in the court of Ferrara. Under the Este Dukes, Ferrara became a major center of literary and artistic patronage. The Latin literary output of the court, however, has received insufficient scholarly scrutiny. The text is a verse funeral elegy of Eleonora of Aragon (1450-1493), the first Duchess of Ferrara. Eleonora was a remarkable woman whose talents and indefatigable efforts on behalf of her husband, her children, and her state, won her accolades both at home and abroad. She also served as a prototype for the remarkable careers of her two daughters, Isabella d'Este, and Beatrice d'Este, who are celebrated for their erudition and patronage of arts and letters. The text is a mirror of the Estense court and reveals to us how its members no doubt saw themselves, at the very peak of its temporal power and the height of its prestige as a center of cultural creativity. It is also important for the striking portrait it presents of Eleonora. Ercole Strozzi chose to call his poem an epicedium, an ancient minor literary …
Date: December 2010
Creator: Cassella, Dean Marcel
System: The UNT Digital Library
Demographic and Psychosocial Contributions to the Expression of Schizotypal Personality Traits. (open access)

Demographic and Psychosocial Contributions to the Expression of Schizotypal Personality Traits.

Previous research suggests there are a number of variables that are associated with the expression of schizotypal personality disorder (SPD) symptoms. Such variables include childhood trauma, depression and anxiety, substance use, normal-range personality traits, ethnicity, and gender. However, research to date has not examined all of these variables in a single study to determine how they may be interrelated or differentially related to SPD symptom domains. Of particular interest is the association of these variables as explained by the diathesis-stress model. This study utilized a convenience sample of 298 undergraduate students to examine a continuous range of scores for symptoms of SPD and how the interrelation of biological factors such as gender and ethnicity and psychosocial factors and stressors such as childhood trauma and personality traits, specifically neuroticism and extroversion, influence the expression of SPD symptoms. It was predicted that anxiety, depression, stress, and childhood trauma would positively correlate to SPD symptoms. It was also hypothesized that neuroticism and substance use would positively correlate to schizotypal traits and extroversion would be negatively correlated to schizotypal traits as measured by the Schizotypal Personality Questionnaire-Brief. It was further hypothesized that psychosocial stressors would be moderated by the aforementioned biological factors.
Date: December 2010
Creator: Hernandez, Nikki
System: The UNT Digital Library
Depression in Diabetic and Non-Diabetic Individuals: Physical Activity, Nutrition, and Diet (open access)

Depression in Diabetic and Non-Diabetic Individuals: Physical Activity, Nutrition, and Diet

About 8.3% of individuals diagnosed with diabetes mellitus (DM) are diagnosed with comorbid depression, a higher rate than the general adult population. This project examined the differences of depression symptoms experienced between diabetic and matched non-diabetic individuals and the relationship of daily activity and nutrition behaviors with depression between these groups. The 2005-2006 National Health and Nutrition Examination Survey (NHANES) was utilized to assess: depression symptoms, diabetic glycemic control as measured by glycoginated hemoglobin (HbA1c), amount of physical activity, percentage of macronutrients, daily frequencies of foods consumed, and the use of nutritional food labels to make food choices. A sample of diabetic (n = 451) and non-diabetic individuals (n = 451) were matched to on age, gender, ethnicity, and education. The diabetic individuals experienced greater depression on both continuous and ordinal diagnostic variables. Counter to expectation, there was no relationship observed between depression and HbA1c in diabetic individuals, r = .04, p > .05.
Date: December 2010
Creator: Edwards, Kate G.
System: The UNT Digital Library
Design and Implementation of Communication Platform for Autonomous Decentralized Systems (open access)

Design and Implementation of Communication Platform for Autonomous Decentralized Systems

This thesis deals with the decentralized autonomous system, in which individual nodes acting like peers, communicate and participate in collaborative tasks and decision making processes. An experimental test-bed is created using four Garcia robots. The robots act like peers and interact with each other using user datagram protocol (UDP) messages. Each robot continuously monitors for messages coming from other robots and respond accordingly. Each robot broadcasts its location to all the other robots within its vicinity. Robots do not have built-in global positioning system (GPS). So, an indoor localization method based on signal strength is developed to estimate robot's position. The signal strength that the robot gets from the nearby wireless access points is used to calculate the robot's position. Trilateration and fingerprint are some of the indoor localization methods used for this purpose. The communication functionality of the decentralized system has been tested and verified in the autonomous systems laboratory.
Date: December 2010
Creator: Gottipati, Naga Sravani
System: The UNT Digital Library
Determinants of Mental Health Problems Among College Students (open access)

Determinants of Mental Health Problems Among College Students

Many college students have reported struggling with mental health problems while dealing with challenging demands of college. The initial theoretical framework for this research was Pearlin's stress process model (SPM). Building on the SPM, the three additional mediating variables of perceived control, meaninglessness, and financial worries were added to create a composite model for the research. Mental health outcomes in the model were measured by a comprehensive range of factors, which included: psychological distress, suicide, substance abuse, and anger. Data were collected from a non-probability convenience sample of 463 undergraduate students attending a large state supported university in the southwestern region of the United States. Among the social status variables measured, being married, female, and white were significant predictors of poor mental health in the sampled college students. Poor self-image, feeling of meaninglessness, and worrying about current and future finances were significant mediating variables. Poor mental health could make individuals overwhelmed and discouraged. This is a formula for failure in college. The results of this study contribute to a better understanding of the correlates of mental health problems among college students. A greater understanding means that families and college administrations will have better ideas about how to intervene to reduce …
Date: December 2010
Creator: Mirbaha-Hashemi, Fariba
System: The UNT Digital Library
Determination of Bioconcentration Potential of Selected Pharmaceuticals in Fathead Minnow, Pimephales promelas, and Channel Catfish, Ictalurus punctatus (open access)

Determination of Bioconcentration Potential of Selected Pharmaceuticals in Fathead Minnow, Pimephales promelas, and Channel Catfish, Ictalurus punctatus

The primary objective of this work was to determine the tissue-specific bioconcentration factors (BCFs) of the selected pharmaceuticals: norethindrone (NET), ibuprofen (IBU), verapamil (VER), clozapine (CLZ) and fenofibrate (FFB) in two freshwater fishes: fathead minnow and channel catfish. BCF tests on fathead followed the standard OECD 42-day test while a 14-day abridged test design was used in catfish exposures. Additional objectives included a) comparing the measured BCFs to the US EPA's BCFWIN model predicted values, b) comparing the BCF results from the standard and reduced tests, and c) prediction of chronic risk of the pharmaceuticals in fish using the human therapeutic plasma concentrations. Each test included uptake and depuration phases to measure tissue-specific kinetic BCFs. The results indicated that all the pharmaceuticals, except IBU, have the potential for accumulation in fish. Estimated BCFs for NET, VER and FFB may not be significant in view of the current regulatory trigger level (BCF &#8805; 2000); however, CLZ's BCF in the liver had approached the criterion level. Significant differences were noticed in the tissue-specific uptake levels of the pharmaceuticals with the following general trend: (liver/kidney) > (gill/brain) > (heart/muscle) > plasma. IBU uptake was highest in the plasma. When compared to the measured …
Date: December 2010
Creator: Nallani, Gopinath C.
System: The UNT Digital Library
Domestic Violence Shelters in Texas: Responding to Programming Needs of Older Victims of Intimate Partner Violence (open access)

Domestic Violence Shelters in Texas: Responding to Programming Needs of Older Victims of Intimate Partner Violence

This study examined if domestic violence shelters in Texas are responding to the needs of older female victims of intimate partner violence. Data for this study was collected through online questionnaire surveys of 45% of Texas domestic violence shelters. Findings of this study indicated that less than 10% of Texas shelters are providing specialized programming for older victims of IPV. In Texas, the demographic growth of older adults has remained comparable to increased national trends. The state of Texas will face several policy implications and social issues related to an older population that is rapidly growing. This includes, the importance of addressing certain members of an aging population who continue to fall victim to domestic violence. Furthermore, an unchanged resource of safety for victims of IPV is domestic violence shelters. Therefore, this study challenges current domestic violence shelter policies to address this issue of a rapidly growing segment of the Texas population. This study found less than 10% of shelters in Texas, who participated in this study, were providing specialized programming and outreach for older victims. Important practical implications for domestic violence shelter programming in Texas is provided.
Date: December 2010
Creator: Lozano, Yvonne M.
System: The UNT Digital Library
Eating from the Tree of Knowledge: The Impact of Visual Culture on the Perception and Construction of Ethnic, Sexual, and Gender Identity (open access)

Eating from the Tree of Knowledge: The Impact of Visual Culture on the Perception and Construction of Ethnic, Sexual, and Gender Identity

This study explores the way that visual culture and identity creates understanding about how the women in my family interact and teach each other. In the study issues of identity, liminality, border culture, are explored. The study examines how underrepresented groups, such as those represented by Latinas, can enter into and add to the discourses of art education because the women who participated have learned to maneuver through the world, passing what they have learned to one another, from one generation to the next. Furthermore, the study investigates ways in which visual cues offer a way for the women in my family to negotiate their identity. In the study the women see themselves in signs, magazines, television, dolls, clothing patterns, advertisements, and use these to find ways in which to negotiate the borderlands of the places in which they live. Although the education that occurred was informal, its importance is in creating a portal through which to self reflect on the cultural work of educating.
Date: December 2010
Creator: Peralta, Andrés
System: The UNT Digital Library
Educators' Perceptions of the Importance of Selected Competencies for Teachers of Students with Emotional and Behavioral Disorders and their Perceptions of Personal Proficiency (open access)

Educators' Perceptions of the Importance of Selected Competencies for Teachers of Students with Emotional and Behavioral Disorders and their Perceptions of Personal Proficiency

This study investigated educators' perceptions of the importance of competencies for teachers of students with emotional and behavioral disorders and their own proficiency in the competencies. Participants included educators who had completed university-based coursework on emotional and behavioral disorders. Competencies from the Qualification and Preparation of Teachers of Exceptional Children study were correlated with CEC's content standards and knowledge skill sets for special education teachers of individuals with emotional and behavioral disorders. Participants ranked 88 competencies on importance and proficiency. Results revealed that educators' proficiency in competencies, their years of experience, and level of education contribute a significant percentage of variance in their ratings of the importance of competencies. Implications for further research are provided.
Date: December 2010
Creator: Wanyonyi-Short, Maureen N.
System: The UNT Digital Library
The Effect of High-Probability Request Sequences on Latency to Comply with Instructions to Transition in a Child With Severe Mental Retardation (open access)

The Effect of High-Probability Request Sequences on Latency to Comply with Instructions to Transition in a Child With Severe Mental Retardation

This study investigated the effect of implementing high-probability request sequences prior to the delivery of instructions to transition in a child with severe mental retardation. Data were collected on latency to comply with a low-probability request to transition and a modified version of the low-probability request. Implementation of high-probability request sequences resulted in shortened latencies to comply with the modified low-probability request instructing the child to engage in a preferred activity located at the endpoint of the transition.
Date: December 2010
Creator: Carpentieri, Michelle Lee
System: The UNT Digital Library
Effect of Polyphosphoric Acid on Aging Characteristics of PG 64-22 Asphalt Binder (open access)

Effect of Polyphosphoric Acid on Aging Characteristics of PG 64-22 Asphalt Binder

This research presents the results on an experimental investigation to identify the effect of polyphosphoric acid (PPA) on aging characteristics of an asphalt binder. Addition of PPA to asphalt binders is said to improve performance of flexible pavements. Asphalt binder PG 64-22 in modified and unmodified conditions was subjected to aging in the laboratory using a regular oven and also simulated short term aging using rolling thin film oven (RTFO) test. Aging experiments were conducted to analyze the extent of oxidation in terms of changes in molecular structure of the asphalt binder. These changes were appraised using Fourier transform infrared (FTIR) spectroscopy, dynamic shear rheometer (DSR), and epifluorescence microscopy tests. FTIR was used to determine the changes in major bands with addition of PPA. Stiffness and viscoelastic behaviors of asphalts were determined from the DSR test. The stiffness is measured by calculating the shear modulus, G* and the viscoelastic behavior is measured by calculating the phase angle, sin &#948;. Epifluorescence microscopy is a tool used to study properties of organic or inorganic substances. The morphological characteristics of PPA modified asphalt samples were observed through epifluorescence microscopy. Epifluorescence microscopy reveals the polymer phase distribution in the asphalt binders. Results of this …
Date: December 2010
Creator: Ramasamy, Naresh Baboo
System: The UNT Digital Library
The Effects of Copying Before, Copying After, and Guessing on Acquisition Rate and Retention (open access)

The Effects of Copying Before, Copying After, and Guessing on Acquisition Rate and Retention

Computer-based instructional programs are being used more frequently in classrooms. While these programs offer many benefits from traditional teaching methods, humans still need to program them. There is inconsistency in the literature regarding the best way to design such programs. The purpose of this study was to evaluate the effects of three training procedures in teaching individuals to type a specified three-letter response in the presence of a corresponding symbol. Results show that the training format that prompted individuals to copy the correct response before the opportunity to respond was more efficient than viewing the correct response after an error, or copying the correct response after an error. A discussion of the results as well as implications for classroom use is also provided.
Date: December 2010
Creator: Pinkelman, Sarah Ellen
System: The UNT Digital Library