UNT Theses and Dissertations - 259 Matching Results

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Ability Estimation Under Different Item Parameterization and Scoring Models

Description: A Monte Carlo simulation study investigated the effect of scoring format, item parameterization, threshold configuration, and prior ability distribution on the accuracy of ability estimation given various IRT models. Item response data on 30 items from 1,000 examinees was simulated using known item parameters and ability estimates. The item response data sets were submitted to seven dichotomous or polytomous IRT models with different item parameterization to estimate examinee ability. The accuracy of the ability estimation for a given IRT model was assessed by the recovery rate and the root mean square errors. The results indicated that polytomous models produced more accurate ability estimates than the dichotomous models, under all combinations of research conditions, as indicated by higher recovery rates and lower root mean square errors. For the item parameterization models, the one-parameter model out-performed the two-parameter and three-parameter models under all research conditions. Among the polytomous models, the partial credit model had more accurate ability estimation than the other three polytomous models. The nominal categories model performed better than the general partial credit model and the multiple-choice model with the multiple-choice model the least accurate. The results further indicated that certain prior ability distributions had an effect on the accuracy of ability estimation; however, no clear order of accuracy among the four prior distribution groups was identified due to an interaction between prior ability distribution and threshold configuration. The recovery rate was lower when the test items had categories with unequal threshold distances, were close at one end of the ability/difficulty continuum, and were administered to a sample of examinees whose population ability distribution was skewed to the same end of the ability continuum.
Date: May 2002
Creator: Si, Ching-Fung B.
Partner: UNT Libraries

An Analysis of the Effectiveness of Computer Assisted Instruction in General Chemistry at an Urban University.

Description: The science-major General Chemistry sequence offered at the University of Houston has been investigated with respect to the effectiveness of recent incorporation of various levels of computer technology. As part of this investigation, questionnaire responses, student evaluations and grade averages and distributions from up to the last ten years have been analyzed and compared. Increased use of web-based material is both popular and effective, particularly with respect to providing extra information and supplemental questions. Instructor contact via e-mail is also well-received. Both uses of technology should be encouraged. In contrast, electronic classroom presentation is less popular. While initial use may lead to improved grades and retention, these levels decrease quickly, possibly due to a reduction in instructor spontaneity.
Date: May 2002
Creator: McGuffey, Angela
Partner: UNT Libraries

And Drops of Rain Fall Like Tears: A Composition for Electroacoustic Music and Video

Description: And Drops of Rain Fall Like Tears is a composition for electroacoustic music with an optional ambient video component. The composition consists of a single movement electroacoustic work twenty-two minutes in duration. The piece creates an immersive sonic environment within the confines of a typical concert space, thereby recreating the powerful temper and subtle beauty of nature from different sonic perspectives. The paper is divided into four chapters, each discussing an element of the piece in detail. The introduction presents background information and compositional approach for the composition. Chapters 1 through 4 present detailed information related to the creation of both the electroacoustic music and video elements of the piece. Chapter 4 contains relevant information to the performance of the piece.
Date: May 2002
Creator: Thompson, Michael Allen
Partner: UNT Libraries

Attrition Rates of Teachers Trained in Alternative Teacher Certification Programs, Those Trained in the Centers for the Professional Development of Teachers, and Those Trained in Traditional University Programs.

Description: This study uses teacher employment data provided by the State Board for Educator Certification to examine the similarities and differences between initial employment and attrition rates of teachers trained in three prevalent types of Texas teacher preparation programs; alternative certification programs (ACP), the centers for professional development of teachers (CPDT), and traditional certification programs (TCP). The population for the study includes all Texas teachers who completed training in these programs in 1995, 1996, and 1997. The study found that ACP participants gain employment as Texas public school teachers at a significantly higher rate than their CPDT and TCP trained peers in year-one after completion of their training. However, ACP completers experience higher attrition rates in each of the subsequent years investigated. The study concludes that the overall cumulative attrition rate of new teachers trained in these programs is not as pronounced as originally presumed, but that low production levels cannot keep up with the growing demand for new teachers. Teacher preparation program leaders must seek ways to recruit and train more teachers.
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Date: May 2002
Creator: Harris, Steven A.
Partner: UNT Libraries

Autoradiographic Localization of Carbachol-Induced Second Messenger Response in the Rat Spinal Cord Following Inflammation.

Description: This study examined central mechanisms of persistent pain using an autoradiographic technique to localize phosphoinositide hydrolysis (PI) in the rat spinal cord dorsal horn. The lateral half of laminae I-II showed the highest levels of baseline PI turnover and carbachol-stimulated PI turnover in normal animals as well as after inflammation. Inflammation resulted in increased baseline PI turnover in this region of the ipsilateral (76%) and contralateral (65%) dorsal horns. Carbachol increased PI turnover in this region in normal rats (55%) and following inflammation (ipsilateral: 46%, contralateral: 45%). The absolute magnitudes of these increases were 1.85, 2.71, and 2.51 nCi/mg, respectively. The results of this study demonstrate the involvement of PI turnover in neural mechanisms of persistent pain, and provide evidence for the involvement of cholinergic systems in this process. Because spinal cholinergic systems have been reported to be anti-nociceptive, the present results appear to reflect an upregulation of anti-nociceptive activity in response to inflammation. Thus, the spinal cholinergic system may be a regulatory site within the anti-nociceptive pathway, and may provide an attractive target for the development of new therapeutic agents.
Date: May 2002
Creator: Moore, Jack
Partner: UNT Libraries

A Behavioral Economic Analysis of the Effects of Unit Price Sequence on Demand for Money in Humans.

Description: Three groups of participants were exposed to different unit price sequences. Unit prices for all groups ranged from unit price 1 to 21. Analyses of demand curves, response rates, session duration, and elasticity coefficients suggest that the sequence of exposure to unit prices can affect the elasticity of demand. In addition, the size of unit price contrast, direction of unit price change, and proximity to experimental milestones also may affect the consumption of monetary reinforcers.
Date: May 2002
Creator: Williams, Jack Keith
Partner: UNT Libraries

Blackland Prairie

Description: Blackland Prairie contains a scholarly preface, “Cross Timbers,” that discusses the emerging role of place as a narrative agent in contemporary fiction. The preface is followed by six original short stories. “Parts” depicts the growth of a boy's power over his family. “A Movie House to Make Us All Rich” involves the sacrifice of familial values by the son of Italian immigrants in the early 20th century. “The Place on Chenango Street” is about a man who views his world in monetary terms. “The Nine Ideas For A Happier Whole” explores the self-help industry and personal guru age. “All The Stupid Things I Said” is about a long-separated couple meeting for very different reasons. “Flooded Timber” concerns a couple who discover hidden reasons for their relationship's longevity.
Date: May 2002
Creator: Magliocco, Amos
Partner: UNT Libraries

Burying the War Hatchet: Spanish-Comanche Relations in Colonial Texas, 1743-1821

Description: This dissertation provides a history of Spanish-Comanche relations during the era of Spanish Texas. The study is based on research in archival documents, some newly discovered. Chapter 1 presents an overview of events that brought both people to the land that Spaniards named Texas. The remaining chapters provide a detailed account of Spanish-Comanche interaction from first contact until the end of Spanish rule in 1821. Although it is generally written that Spaniards first met Comanches at San Antonio de Béxar in 1743, a careful examination of Spanish documents indicates that Spaniards heard rumors of Comanches in Texas in the 1740s, but their first meeting did not occur until the early 1750s. From that first encounter until the close of the Spanish era, Spanish authorities instituted a number of different policies in their efforts to coexist peacefully with the Comanche nation. The author explores each of those policies, how the Comanches reacted to those policies, and the impact of that diplomacy on both cultures. Spaniards and Comanches negotiated a peace treaty in 1785, and that treaty remained in effect, with varying degrees of success, for the duration of Spanish rule. Leaders on both sides were committed to maintaining that peace, although Spaniards were hampered by meager resources and Comanches by the decentralized organization of their society. The dissertation includes a detailed account of the Spanish expedition to the Red River in 1759, led by Colonel Diego Ortiz Parrilla. That account, based on the recently discovered diary of Juan Angel de Oyarzún, provides new information on the campaign as well as a reevaluation of its outcome. The primary intention of this study is to provide a balanced account of Spanish-Comanche relations, relying on the historical record as well as anthropological evidence to uncover, wherever possible, the Comanche side of the story. The ...
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Date: May 2002
Creator: Lipscomb, Carol A.
Partner: UNT Libraries

Carl Gottlieb Reissiger (1798-1859) Forgotten Composer for the Clarinet

Description: Carl Gottlieb Reissiger was a successful German composer, conductor, and teacher in the first half of the nineteenth century. At the height of his career, he was Hofkapellmeister of theater and opera in Dresden, a position he held until his death. He was a composer of more than 200 works in a multitude of different genres. Today he is mainly known as a composer of opera, a small portion of his total output as a composer. He wrote approximately eighty piano solos, eighty collections of songs or duets, nine masses, and many smaller sacred choral works, as well as 27 piano trios, seven piano quartets, and three piano quintets. In addition to these many works, he wrote five works for the clarinet: Concertino, op. 63, Duo Brillant for clarinet and piano, op. 130, Fantasie, op. 146, Second Fantasie, op. 180, and Adagio und Rondo alla polacca, op. 214. This document provides a biographical sketch of Reissiger, including his personal life, his life as a conductor, and his life as a composer. It also provides a look at the artistic life of his day: his fellow composers and the music they were writing for clarinet, outstanding clarinetists and the different instruments they were playing. The aim of this study is to provide a stylistic analysis of Reissiger's five works for clarinet, including a discussion of form, melody, harmony, and rhythm. This document puts forth the proposal that these works are worth resurrecting and that Reissiger, as a composer of clarinet music, is more than just a secondary composer.
Date: May 2002
Creator: Coltman, Charles Arthur
Partner: UNT Libraries

The Characteristics of Sociological Practitioners: A Social Psychological Examination

Description: Questionnaires were sent by mail and e-mail to 143 members of the Sociological Practice Association. The purpose of the questionnaire was to measure the role expectations as qualities (competencies), role expectations as actions, and role enactments of the respondents'. An additional goal was to examine how respondents perceived their work to be sociological in nature, and how they saw their work as different from the practices of social workers, counselors, and psychologists. The first question that was addressed was, “Do sociological practitioners have clear and unambiguous role expectations for their work as practitioners?” The data showed that most role expectations measured as competencies were clear and unambiguous, and only a few were ambiguous and unclear. The second question addressed was, “Do sociological practitioners perceive their role enactments to differ from other helping professionals such as social workers, counselors, and psychologists?” The data showed that sociological practitioners do perceive their role enactments to be different because of their use of sociological theory and their focus on social structures. The final question asked was, “How do sociological practitioners perceive their work as sociological in theory, methods, or both?” The data showed that sociological practitioners perceive their work as sociological based on their use of sociological theory. Most respondents reported that they used common scientific methods, and few reported the use of psychological theory.
Date: May 2002
Creator: Carr, Joel Lance
Partner: UNT Libraries

Characterization of cDNA and Genomic Clones for a Palmitoyl-acyl Carrier Protein Thioesterase and an Osmotin-Like PR5 Protein in Gossypium Hirsutum.

Description: Putative cotton cDNA clones and cognate genomic clones for a palmitoyl-acyl carrier protein (ACP) thioesterase (PATE) and an osmotin-like pathogenesis-related 5 (PR5) protein have been isolated and characterized. PATE is a class B fatty acid thioesterase with specificity for saturated long-chain fatty acids such as palmitate, and is implicated as a key enzyme to be targeted for regulation of fatty acid synthesis in order to alter cotton seed oil profiles. A nearly full-length 1.7-kb cDNA clone was isolated using a hybridization probe derived from an Arabidopsis PATE cDNA clone designated TE 3-2. A 17-kb genomic segment encompassing the PATE gene was also isolated, which has six exons and five introns with high sequence identity with other FatB cDNA/gene sequences. The deduced PATE preprotein amino acid sequence of 413 residues has putative signal sequences for targeting to the chloroplast stroma. PR5 proteins called osmotins are made in response to fungal pathogen stress or osmotic stress (water deprivation or salt exposure). Osmotins may actually form pores in fungal membranes, leading to osmotic rupture and destruction of the fungal cells. A cotton osmotin-like PR5 cDNA insert of 1,052 base-pairs was isolated and shown to encode a preprotein of 242 amino acids and is predicted to be secreted to the extracellular matrix as a neutral isoform. The deduced amino acid sequence has 16 cysteine residues that are highly conserved in osmotin-like proteins and are important in stabilizing the three-dimensional structure seen in thaumatin, zeamatin, and PR5-d. The intronless cognate cotton genomic clone has two putative ethylene response elements (GCC boxes) found in other PR5 gene promoter regions, as well as several tentative promoter/enhancer elements possibly involved in spatial/temporal gene expression.
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Date: May 2002
Creator: Yoder, David W.
Partner: UNT Libraries

College Freshman Biology Two Semester Course: Integrating Deep Processing Teaching Techniques

Description: Development of a college level freshman biology course was undertaken in response to government reports that American students have fallen behind students of other countries in the area of the sciences. Teaching strategies were investigated to accomplish two objectives, to define essential academic material to include in the course and to investigate teaching techniques that would increase deep processing of the information. An active process that consisted of applying the cognitive information to solving problems or developing answers to questions was defined as critical thinking. Critical thinking was incorporated into the course by the use of case studies.
Date: May 2002
Creator: Blevins, Mary Jean
Partner: UNT Libraries

Coming in From the Cold: Integration into the European Union and Public Opinion on Democracy and the Market Economy in Central and Eastern Europe.

Description: The political economy transformations of the countries of Central and Eastern Europe have received a great deal of attention over the past decade. The focus of much research has been to examine the internal national reorientations of the countries with regard to the changes in political and economic conditions. The importance of the international reorientation of these countries toward Western Europe in general and the European Union in particular has been generally overlooked. This dissertation examines public opinion on the political and economic transformations within the framework of the direction of the international reorientations of the countries. The countries were divided into three categories, those that can be expected to be invited to join the European Union in the next enlargement, those that can be expected to join the European Union in a subsequent enlargement, and the countries not seeking European Union membership. Public opinion on democracy and the market economy and attitudinal factors that influence these opinions are compared in 16 countries in Central and Eastern Europe. The data are from the Central and East European Barometers 3-7 (1992 - 1996). The findings suggest that general opinions regarding satisfaction with democracy are not related to the status of the country seeking membership in the European Union while support from the market economy does differ. When examining attitudinal factors that are related to satisfaction with democracy and support for the market economy, differences emerged between the three categories of countries. These findings suggest that public opinion is in part shaped by the international orientations of the country and that changes in public opinion are important in understanding the political and economic transformation processes.
Date: May 2002
Creator: Zottarelli, Lisa K.
Partner: UNT Libraries

A Comparison of Aural and Visual Instructional Methodologies Designed to Improve the Intonation Accuracy of Seventh Grade Violin and Viola Instrumentalists.

Description: The purpose of the study was to compare two instructional methodologies designed to improve the intonation accuracy of seventh grade violin and viola instrumentalists. The collection of data was in regard to (1) instructional methodology: aural and aural/visual, (2) performance tasks: A, B, and C; (3) individual pitches (seven from each of the music tasks), and (4) differences between instrument groups: violin and viola. Sixty-eight seventh grade string students from three string classes of two middle schools were randomly assigned to two experimental groups: (a) aural and (b) aural/visual. The instructional period was implemented daily in ten-minute sessions during twenty days by the orchestra instructors of each school. A pretest-posttest format was used to determine if there were any changes in the subjects' intonation accuracy from prior to after the instructional phase was implemented, and if these changes could be attributed to any of the methodologies. The testing material used on both testing sessions included three performance tasks composed of seven notes each. Subjects were recorded on both testing occasions. The data were the scores of absolute pitch deviation, measured in cents from equal temperament, from the pre- and postest; these were treated with analysis of variance. The ANOVA on the posttest scores indicated a non-significant difference between the instructional methodologies in their effectiveness to improve the subjects' ability to play in tune.
Date: May 2002
Creator: Núñez, Mario Leoncio
Partner: UNT Libraries

A Comparison of Texas Pre-service Teacher Education Programs in Art and the 1999 National Art Education Association's Standards for Art Teacher Preparation

Description: Texas programs in pre-service art teacher preparation vary little. Since 1970, the National Art Education Association (NAEA) has created voluntary standards in hopes of decreasing variability among programs. In 1999, the NAEA published Standards for Art Teacher Preparation, outlining 20 content areas that art pre-service programs should provide their students. To obtain information on the implementation and the extent to which these 20 standards are being implemented, a questionnaire was sent to all programs in Texas. The 20 standards were the dependent variable for the study. The four independent variables used in this ex post facto study were: the size of the institution where the program exists; the number of full-time art faculty; the number of full-time art education faculty; and, the number of undergraduate art education students who graduated last year. The 20 standards or provisions were scored on a Lickert scale with six options: zero (not taught) to five (comprehensively taught). The response size (N = 23) was 47% of the state's 49 approved programs. The results from the survey suggest no significant difference among programs. However, the results showed a significant difference in the number of provisions taught between programs with no art educators and those with 1 to 3 art educators. One art educator seemed to increase the number of pedagogical provisions taught but did not increase the extent or enhance the degree to which each provision was taught. A comprehensively taught response to the NAEA provisions on the questionnaire was further investigated through analysis of catalog course descriptions and correspondence with participants. The results are estimated in credit hours and indicate that there may be a point where time on task decides the limit that constitutes a comprehensive preparation. Perspectives on content are discussed and regarded as too subjective to define comprehensive preparation. Comprehensive time ...
Date: May 2002
Creator: Breitenstein, Gary
Partner: UNT Libraries

Competency to Stand Trial: A Systematic Evaluation and Validation of the GCCT, MacCAT-CA, and ECST as Competency Measures

Description: Competency to stand trial cases constitute the largest percentage of forensic referrals for clinical psychologists. Furthermore, research suggests that the use of forensic measures facilitates the decisions of competency made by forensic examiners. This study investigated the construct validity of three competency measures: (a) the GCCT-MSH, (b) the MacCAT-CA, and (c) the ECST with 100 adult males incarcerated at the Tarrant County Jail in Fort Worth, TX. Construct validity was investigated via the use of a multitrait-multimethod research design for the three-prong conceptualization of the Dusky standard. Results indicated that current competency measures do an adequate job of assessing for factual understanding, but lack construct validity for two prongs: rational understanding and the ability to consult with counsel. In addition, the atypical presentation scales of the both GCCT and the ECST performed well at screening individuals for feigning. Finally, prediction of competency from clinical variables was also investigated. Psychotic symptoms and overall impairment were the strongest predictors of incompetency.
Date: May 2002
Creator: Grandjean, Nicole Rae
Partner: UNT Libraries

A Computational Study on 18+δ Organometallics

Description: The B3LYP density functional has been used to calculate properties of organometallic complexes of Co(CO)3 and ReBr(CO)3, with the chelating ligand 2,3-bisphosphinomaleic anhydride, in 19- and 18-electron forms. The SBKJC-21G effective core potential and associated basis set was used for metals (Co/Re) and the 6-31G* basis set was used for all other elements. The differences of bond angles, bond distances, natural atomic charges and IR vibrational frequencies were compared with the available experimental parameters. The differences between the 19- and 18-electron systems have been analyzed. The results reveal that the 19th electron is mostly distributed over the ligand of 2,3-bisphosphinomaleic anhydride, although partially localized onto the metal fragment in 1 and 2*. Two different methods, IR-frequencies and natural atomic charges, were used to determine the value of δ. Present computed values of δ are compared with available experimental values, and predictions are made for unknown complexes.
Date: May 2002
Creator: Yu, Liwen
Partner: UNT Libraries

Computer Supported Collaboration: Is the Transfer of Cognitive Structures Mediated by Mode of Communication?

Description: The objective of this study was to observe evidence of structural transfer among subjects in a group problem-solving activity and determine whether mode of collaborative technology or use of a priming agent affected the nature of transferred structures. Evidence for structural transfer is found in three theoretical perspectives: organizational ditransitive (linguistic) verb structures, adaptive structuration theory, and mental model transfer theory. Dependent variables included various grammatical structures and coefficients derived from pretest and posttest scores on David Kolb's Learning Styles Inventory, modified for the experiment. The combination of changes in grammatical frequencies and learning style may suggest that one or more media or the priming agent may affect structural transfer. Results indicate that groups using the GroupSystems™ collaborative technology produced less overall linguistic content than did subjects using a generic chat system, but employed more complex language as indicated by frequency of the organizational ditransitive verb structure. Also, subjects supplied with an organization chart (priming agent) during the group problem-solving session experienced greater change on the learning styles inventory than did those participating in the session without the chart. These findings suggest that mode of communication and use of priming agents may contribute positively or negatively to the transfer of structures among group members. Researchers, collaborative system designers, organizational leaders, trainers & educators, and frequent collaborative technology system end-users should be aware of these potential affects. Suggestions for future research are provided. Relationship of theoretical foundations of structural transfer to constructivism is discussed.
Date: May 2002
Creator: Bandy, Kenneth E.
Partner: UNT Libraries

The Construct Validity of Self-Reported Historical Physical Activity

Description: The purpose of this study was to determine the construct validity of self-reported historical walking, running, and jogging (WRJ) activity. The criterion measure was concurrent performance on a maximal treadmill test. Subjects completed a medical exam and treadmill test between the years 1976 and 1985, and completed a follow-up questionnaire in 1986. Questionnaire included an item that assessed WRJ for each year from 1976 through 1985. Data analysis included Spearman correlations, partial correlations, ANOVA, and ANCOVA. Results indicated self-reported historical WRJ can be assessed with reasonable validity when compared with concurrently measured treadmill performance, and there is no decay in the accuracy of this reporting for up to ten years in the past.
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Date: May 2002
Creator: Bowles, Heather R.
Partner: UNT Libraries

A Content Analysis of Reading Software Commercially Available for Pre-K to 3rd Grade Children.

Description: The purpose of this qualitative study was to investigate the content and characteristics of the currently available commercial reading software for Pre-K through third grade children. The design of the study was a content analysis. Based on the evaluation rubric established by the researcher, ten commercial reading software were selected to be analyzed. By reviewing and transcribing, the data were obtained, and then coded, categorized, and interpreted. The findings from the analysis revealed that all reading software programs offered exercised for practicing basic phonics skills; the alphabetic principle, letter-sound association, word knowledge, sentence building, and reading comprehension. Depending on the software developers, phonics-based practice was presented in two ways; separate skill-based practice emphasis and storybook-reading emphasis. All software programs utilized drill-and-practice, direct instruction and mastery learning methods and utilized gaming strategies to motivate and engage the learners. Multimedia technology was used to make the software more appealing. All reading software programs were developed on the perspectives that view learning to read as the continuum of a child's oral language development and background experience about words. It is recommended that parents and teachers review and select the software based on reliable information sources, use the software as supplementary practice based on the learning objectives identified and individual student needs.
Date: May 2002
Creator: Nakjan, Sutat
Partner: UNT Libraries

A Correlative Study of Gender and Social Style.

Description: This study examines the concepts of social style and gender to determine if a relationship exists between the two constructs. The hypotheses suggested a direct relationship between the categories of the BSRI (masculine, feminine, androgynous, and undifferentiated) and the Social Style Analysis (driver, amiable, expressive, and analytical). Ninety-four participants completed two self-report surveys. Chi-square analysis performed on the data found a significant relationship between feminine and amiable as well as androgynous and expressive. While the analysis suggested that masculine/driver and undifferentiated/analytical were not independent, the relationship found was not significant.
Date: May 2002
Creator: Gross, Amanda
Partner: UNT Libraries

The Crater of Diamonds: A History of the Pike County, Arkansas, Diamond Field, 1906-1972

Description: The first diamond mine in North America was discovered in 1906 when John W. Huddleston found two diamonds on his farm just south of Murfreesboro in Pike County, Arkansas. Experts soon confirmed that the diamond-bearing formation on which Huddleston made his discovery was the second largest of its kind and represented 25 percent of all known diamond-bearing areas in the world. Discovery of the field generated nearly a half century of speculative activity by men trying to demonstrate and exploit its commercial viability. The field, however, lacked the necessary richness for successful commercial ventures, and mining was eventually replaced in the early 1950s by tourist attractions that operated successfully until 1972. At that time the State of Arkansas purchased the field and converted it to a state park. Thus this work tell the rich and complicated story of America'a once and only diamond field, analyzes the reasons for the repeated failures of efforts to make it commercially viable, and explains how it eventually succeeded as a tourist venture.
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Date: May 2002
Creator: Henderson, John C.
Partner: UNT Libraries

Detecting the Presence of Disease by Unifying Two Methods of Remote Sensing.

Description: There is currently no effective tool available to quickly and economically measure a change in landmass in the setting of biomedical professionals and environmental specialists. The purpose of this study is to structure and demonstrate a statistical change-detection method using remotely sensed data that can detect the presence of an infectious land borne disease. Data sources included the Texas Department of Health database, which provided the types of infectious land borne diseases and indicated the geographical area to study. Methods of data collection included the gathering of images produced by digital orthophoto quadrangle and aerial videography and Landsat. Also, a method was developed to identify statistically the severity of changes of the landmass over a three-year period. Data analysis included using a unique statistical detection procedure to measure the severity of change in landmass when a disease was not present and when the disease was present. The statistical detection method was applied to two different remotely sensed platform types and again to two like remotely sensed platform types. The results indicated that when the statistical change detection method was used for two different types of remote sensing mediums (i.e.-digital orthophoto quadrangle and aerial videography), the results were negative due to skewed and unreliable data. However, when two like remote sensing mediums were used (i.e.- videography to videography and Landsat to Landsat) the results were positive and the data were reliable.
Date: May 2002
Creator: Reames, Steve
Partner: UNT Libraries

Determination of the Shelf Life of Aluminum Electrolytic Capacitors.

Description: The aluminum electrolytic capacitor is used extensively in the electric utility industry. A factor limiting the storage of spare capacitors is the integrity of the aluminum oxide dielectric, which over time breaks down contributing to a shelf life currently estimated at one nuclear power electric generating station to be approximately five years. This project examined the electrical characteristics of naturally aged capacitors of several different styles to determine if design parameters were still within limits. Additionally, the effectiveness of a technique known as “Reforming” was examined to determine its impact on those characteristics.
Date: May 2002
Creator: Wynne, Edward McFaddin
Partner: UNT Libraries