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The CMS forward calorimeter prototype design studies and Omega(c)0 search at E781 experiment at Fermilab

Description: In the fit part, the Compact Muon Solenoid (CMS) forward calorimeter design studies are presented. The forward calorimeter consists of quartz fibers embedded in a steel absorber. Radiation damage studies of the quartz fiber and the absorber as well as the results of the first pre-production prototype PPP-I are presented. In the second part, the {Omega}{sub c}{sup 0}search studies at the SELEX (E781) experiment at FermiLab are presented. 107 {+-} 22 {Omega}{sub c}{sup 0} events are observed in three decay modes. The relative branching ratio ({Omega}{sub c}{sup 0} {yields} {Omega}{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup +})/{Beta}({Omega}{sub c}{sup 0} {yields} {Omega}{sup -}{pi}{sup +}) is measured as 2.00 {+-} 0.45(stat) {+-} 0.32(sys).
Date: May 1, 2004
Creator: Ayan, Ahmet Sedat & U., /Iowa
Partner: UNT Libraries Government Documents Department

Art or Craft?

Description: I chose to exhibit sculpture and classical style vessels together to encourage discussion about whether ceramics should be considered a fine art medium. I was interested in experimenting with different forms and textures in order to see which combination would captivate the viewing audience the longest. I found that massive textural sculptural forms held the attention of the viewer more so than did the classical smooth surfaced vessels.
Date: May 2004
Creator: Snelson, Jason
Partner: UNT Libraries

Culturing Vallisneria americana for Restoration Efforts

Description: Robust Vallisneria americana was cultured for restoration purposes. Preliminary studies, with various iron treatments, were conducted to ascertain the amount of phosphorous release into the water column from sediments. There was a significant difference in the amount of phosphorous released if commercial sediment was used with a low iron amendment or without an iron amendment. The second study consisted of planting V. americana on two different sediment types while supplying half of the plants with additional CO2. Plants grown on pond sediment with additional CO2 had significantly more biomass. In the third study all plants were grown on pond sediment, and half were treated with CO2. All plants that were treated with additional CO2 had significantly more biomass than those that were aerated.
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Date: May 2004
Creator: Tanski, Erin M.
Partner: UNT Libraries

Key Components of a Comprehensive Visual Information System for College-Level Design Education Curriculum Analysis

Description: Electronic and computer technology have advanced and transformed graphic design. New technologies are forcing design educators to constantly monitor and update their programs, creating a need for a system to be adopted by college-level institutions to better investigate, evaluate and plan art and design curriculum. The author identifies metaphorical approaches to designing a two-part solution, which includes a Comprehensive Visual Information System (CVIS) and Three-Dimensional Virtual Database (3DVDb), which assign volumetric form to education components based on the form, structure and content of a discipline. Research and development of the conceptual design for the CVIS and 3DVDb are intended to aid in the development of an electronic media solution to be made accessible to students, faculty and administrators.
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Date: May 2004
Creator: Short, Scott Allen
Partner: UNT Libraries

Use of Fading Procedures and Positive Reinforcement to Increase Consumption of Non-Preferred Food in a Child with Autism

Description: Traditionally children with developmental disabilities who develop feeding issues can be at great risk for malnutrition. Failure to eat adequate amounts of food and/or insistence on eating a limited range of foods can be detrimental to a child's health and can lead to other behavioral difficulties. Feeding problems are difficult to treat because high levels of physical prompting can quickly create an aversion to eating as well as cause stress for both parents and children. Behavioral problems that range from moderate to extremely maladaptive can ensue. The question the present study addressed was whether or not a treatment package including only positive reinforcement and fading for a non-preferred food would result in independent eating of the targeted non-preferred food.
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Date: May 2004
Creator: Vorpahl, Cresse Merchant
Partner: UNT Libraries

The Effects of Parent Training on the Amount and Variety of Food Consumed By a Child with Autism.

Description: The current study assessed the effectiveness of a training package, delivered in the form of a manual, to teach a parent to increase the variety and amount of food consumed by her son. The participant was a 5-year-old boy with Pervasive Developmental Disorder and limited food consumption. A changing criterion design across two variables, variety of food and quantity of food, was used. Results were that the parent who used the manual, with limited assistance from the experimenter, did succeed in increasing food variety and quantity of target foods.
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Date: May 2004
Creator: VanKirk, Tessa Schreiber
Partner: UNT Libraries

Preparation and characterization of praseodymium oxide films and powders.

Description: Nanocrystalline praseodymium oxide films have been successfully generated on stainless steel substrates. The electrochemical deposition was performed in the cathode compartment of a divided electrochemical cell with a regular three-electrode configuration. The green films obtained by electrodeposition were then annealed at high temperatures for 1-3 hours. X-ray diffraction revealed the fluorite structure of Pr6O11 and the crystallite size was calculated. X-ray photoelectron spectroscopy was employed to study the composition of the oxide films and also the oxidation state of Pr. Scanning electron microscopy was utilized to study the surface texture and microstructure of deposits. Fourier transform infrared spectrometery was used to investigate the composition of the films. The effects of different conditions on the green films were also studied such as different pH values of the electrolyte solution, different deposition modes, different supporting electrolytes and different applied current densities. Sintering experiments were conducted to investigate the properties of the green films. Praseodymium oxide powders were also successfully prepared by combining electrochemical methods with sintering processes. The praseodymium oxide powders were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The crystallite sizes of the powders were evaluated.
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Date: May 2004
Creator: Shang, Yajuan
Partner: UNT Libraries

The Relationship of Acculturation Stress and Leisure Satisfaction of Hispanic College Students

Description: Hispanics are the fastest growing minority group in the U.S. and signs indicate a similar trend in their college enrollment. Leisure activities are known to have a moderating effect on individuals experiencing stress in their lives. Hispanic organizations registered with a major 4-year metropolitan university were targeted. The hypothesis for this study was there is no relationship between acculturation stress and leisure satisfaction. Results indicate no relationship between acculturation stress and leisure satisfaction. One explanation for this lack of a significant relationship between these two measures might be that these college students had obtained a high level of acculturation, which would explain the relatively low level of acculturation stress reported.
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Date: May 2004
Creator: Pacleb, Selverio V.
Partner: UNT Libraries

Effects of Thickness and Indenter Tip Geometry in Nanoindentation of Nickel Films

Description: Nanoindentation has become a widely used technique to measure the mechanical properties of materials. Due to its capability to deform materials in micro- and nano-scale, nanoindentation has found more applications in characterizing the deformation behavior and determining the mechanical properties of thin films and coatings. This research deals with the characterization of samples received from Center for Advanced Microstructures and Devices (CAMD) and Integran Technologies Inc., Toronto, Canada and the objective of this investigation was to utilize the experimental data obtained from nanoindentation to determine the deformation behavior, mechanical properties of thin films on substrates and bulk materials, and the effect of geometrically different indenters (Berkovich, cubecorner, and conical). X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) analysis were performed on these materials to determine the crystal orientation, grain size of the material, and also to measure any substrate effects like pile-up or sin-in respectively. The results indicate that indentation size effect (ISE) strongly depends on shape of the indenter and less sensitive to penetration depth where as the hardness measurements depends on shape of indenter and depth of penetration. There is a negligible strain rate dependency of hardness at deeper depths and a significant increase in the hardness due to the decrease in grain size and results also indicate that there is no significant substrate effect on thin films for 10% and 20% of film thicknesses. Nanocrystalline material could not validate a dislocation based mechanisms deformation for indentation made by cubecorner and conical indenters in depths less than 1mm.
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Date: May 2004
Creator: Parakala, Padma
Partner: UNT Libraries

Design of Power Amplifier Test Signals with a User-Defined Multisine

Description: Cellular radio communication involves wireless transmission and reception of signals at radio frequencies (RF). Base stations house equipment critical to the transmission and reception of signals. Power amplifier (PA) is a crucial element in base station assembly. PAs are expensive, take up space and dissipate heat. Of all the elements in the base station, it is difficult to design and operate a power amplifier. New designs of power amplifiers are constantly tested. One of the most important components required to perform this test successfully is a circuit simulator model of an entire communication system that generates a standard test signal. Standard test signals 524,288 data points in length require 1080 hours to complete one test of a PA model. In order to reduce the time taken to complete one test, a 'simulated test signal,' was generated. The objective of this study is to develop an algorithm to generate this 'simulated' test signal such that its characteristics match that of the 'standard' test signal.
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Date: May 2004
Creator: Nagarajan, Preeti
Partner: UNT Libraries

Instigating a Necessary Epiphany in Visual Message-Making for Design Educators and Future Communication Designers

Description: Man has used graphic signs and symbols to express a variety of thoughts and feelings since before the invention of writing; they have helped him to preserve the ideologies that have enabled him to articulate his conception of the world. Every culture in every historical era has invested the objects, animals and plants around it with a multitude of different psychological meanings to communicate its essential belief systems and social aspirations. In my document, I chose to shed light on the responsibility I believe design educators must assume regarding their ability to understand and teach the importance of how similar graphic signs, symbols, ideograms and icons are perceived differently by different cultures in the hyper-connected, inter-global economy of 21st century. It is very crucial not to discount the influence and correlation of symbolic, fundamental building blocks of design with the basic psychological functions that inform our subconscious, and are also informed by our individual social and cultural upbringings. People from different cultures may cognate these shapes similarly, but they perceive and encode their meanings based on their particular social and cultural influences. One-size-fits-all communication design solutions rarely work, especially when they are distributed to culturally diverse audiences, because various ethnic audiences view the world and the visual messages that designers create for them through their own self-imposed cultural filters. These filters are informed by language, religion, politics and other shared experiences, and they go beyond what can be externally observed. As communication designers, we need to take the time to study and understand how these filters operate, so that we can accurately convey our clients' messages to the intended audiences so that they might be appropriately encoded and perceived.
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Date: May 2004
Creator: Sarkaria, Gagandeep
Partner: UNT Libraries

Ethics Naturally: An Environmental Ethic Based on Naturalness

Description: In this thesis I attempt to base an environmental ethic on a quality called naturalness. I examine it in terms of quantification, namely, as to whether it can quantified? I then apply the concept to specific areas such as restoration and conservation to create an environmental ethic and to show how such an ethic would be beneficial in general, and especially to policy issues concerning the environment. The thesis consists of three chapters: (1) the definition of nature and natural by way of a historical approach; (2) the place of humans in this scheme; and (3) the place of value and the discussion concerning quantification.
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Date: May 2004
Creator: Leard, Jason
Partner: UNT Libraries

Exhaustivity, continuity, and strong additivity in topological Riesz spaces.

Description: In this paper, exhaustivity, continuity, and strong additivity are studied in the setting of topological Riesz spaces. Of particular interest is the link between strong additivity and exhaustive elements of Dedekind s-complete Banach lattices. There is a strong connection between the Diestel-Faires Theorem and the Meyer-Nieberg Lemma in this setting. Also, embedding properties of Banach lattices are linked to the notion of strong additivity. The Meyer-Nieberg Lemma is extended to the setting of topological Riesz spaces and uniform absolute continuity and uniformly exhaustive elements are studied in this setting. Counterexamples are provided to show that the Vitali-Hahn-Saks Theorem and the Brooks-Jewett Theorem cannot be extended to submeasures or to the setting of Banach lattices.
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Date: May 2004
Creator: Muller, Kimberly O.
Partner: UNT Libraries

A Wet Etch Release Method for Silicon Microelectromechanical Systems (MEMS) Using Polystyrene Microspheres for Improved Yield

Description: One of the final steps in fabricating microelectromechanical devices often involves a liquid etch release process. Capillary forces during the liquid evaporation stage after the wet etch process can pull two surfaces together resulting in adhesion of suspended microstructures to the supporting substrate. This release related adhesion can greatly reduce yields. In this report, a wet etch release method that uses polystyrene microspheres in the final rinse liquid is investigated. The polystyrene microspheres act as physical barriers between the substrate and suspended microstructures during the final liquid evaporation phase. A plasma ashing process is utilized to completely remove the polystyrene microspheres from the microstructure surfaces. Using this process, release yields > 90% were achieved. It is found that the surface roughness of gold surfaces increases while that of the silicon is reduced due to a thin oxide that grows on the silicon surface during the plasma process.
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Date: May 2004
Creator: Mantiziba, Fadziso
Partner: UNT Libraries

Polymorphous

Description: The first section explores how far I could stretch dichotomy in formal terms, while maintaining a visually resonant image. I wanted to manipulate a superficial surface filtered through "natural forms" as seen in scientific imagery. By this I wanted to create access to a place where forms could play and imagination could wander. I was seeking to find a confluence in seemingly opposing forces that would coexist in the same work. The second section answers questions I had established for myself. The most important discovery I made was about the true nature of what I called a dichotomy in my work. The last section discusses the conclusions drawn from mounting the Master of Fine Arts Exhibition. I found that my interests resided more in investigating an already confluent dualism, as opposed to reconciling a conflicting dichotomy.
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Date: May 2004
Creator: Maxwell, Sarah
Partner: UNT Libraries

The Rise, Fall, and Redemption of Oran M. Roberts

Description: This thesis analyzes the political career of Oran M. Roberts during the critical period from 1850 to 1873. Through a reassessment of Roberts's extensive personal papers in the context of modern historical scholarship, the author explains how Roberts's political philosophy reflected the biases and prejudices typical of his era, as well as his own material interests and ambitions. Topic areas covered include Roberts's position on the Compromise of 1850, his constitutional philosophy, his involvement in the secession movement in Texas (including his service as president of the state secession convention), his military career during the Civil War, his participation in Presidential Reconstruction, his views on Congressional Reconstruction, and his role in the process of "redemption" in Texas.
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Date: May 2004
Creator: Klemme, A. Christian
Partner: UNT Libraries

On the Relation between Stimulus Equivalence and Extension of Stimulus Function

Description: The purpose of this study was to examine the relation between stimulus equivalence (briefly, networks of relations among stimuli) and the extension of stimulus function (briefly, spread of effect across network) more closely than has been possible before. The traditional view of this relation suggests that equivalence classes mediate the extension of stimulus function and are, therefore, necessary for any extension to occur. This study used a preparation in which the conditional discriminations required for the development of equivalence classes and the simple discriminations required for the extension of function were trained or tested simultaneously. Results suggest that equivalence are not necessary for the extension of stimulus function though they may be sufficient.
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Date: May 2004
Creator: Hartman, Carrie
Partner: UNT Libraries

Spaces of Compact Operators

Description: In this dissertation we study the structure of spaces of operators, especially the space of all compact operators between two Banach spaces X and Y. Work by Kalton, Emmanuele, Bator and Lewis on the space of compact and weakly compact operators motivates much of this paper. Let L(X,Y) be the Banach space of all bounded linear operators between Banach spaces X and Y, K(X,Y) be the space of all compact operators, and W(X,Y) be the space of all weakly compact operators. We study problems related to the complementability of different operator ideals (the Banach space of all compact, weakly compact, completely continuous, resp. unconditionally converging) operators in the space of all bounded linear operators. The structure of Dunford-Pettis sets, strong Dunford-Pettis sets, and certain spaces of operators is studied in the context of the injective and projective tensor products of Banach spaces. Bibasic sequences are used to study relative norm compactness of strong Dunford-Pettis sets. Next, we use Dunford-Pettis sets to give sufficient conditions for K(X,Y) to contain c0.
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Date: May 2004
Creator: Ghenciu, Ioana
Partner: UNT Libraries

A Historical Survey of the Euphonium and Its Future in Non-Traditional Ensembles Together with Three Recitals of Selected Works by Jan Bach, Neal Corwell, Vladimir Cosma, and Others

Description: The euphonium has been a respected member of military bands, brass bands, and civilian concert (wind) bands since its invention in 1843. These bands were very visible to the public, and often performed popular music of the day. Since then, the euphonium has had occasional use in orchestral works, jazz, and in brass chamber groups as well. However, by the middle of the 20th century, its traditional use as an instrument of the wind band resulted in a prevailing attitude of the music world toward the euphonium as an instrument strictly for that purpose. This attitude, along with changing popular tastes in music, has over time caused professional opportunities for euphoniumists to become very limited. This lack of public expose for the instrument has therefore resulted in people outside of wind band experience being unaware of the euphonium's existence. There have been, however, positive signs in the last thirty years that changes are taking place in prevailing attitudes toward the euphonium. The formation of the Tubists Universal Brotherhood Association (renamed the International Tuba Euphonium Association in 2000) as a supportive professional organization, the emergence of the tuba/euphonium ensemble as chamber music, new solo works by major composers, and the use of euphonium in nontraditional ensembles have all served to promote the instrument. The future of the euphonium will depend on exploring the possibilities of using the instrument in non-traditional ensembles, and on changing the way euphonium is taught in a way that will adjust to the changing musical climate.
Date: May 2004
Creator: Cottrell, Jeffrey S.
Partner: UNT Libraries

Clockwork Plums

Description: Based on a story by Joshua Forehand with additional lyrics by Joshua Bradford, Clockwork Plums is an original musical work that integrates techniques and ideas from composers and different cultures. The accompanying essay about the work includes a summary of the story, "Clockwork Plums," some historical background covering 30 years of pop music, an analysis focusing on the use of African and Reichian compositional devices, and discussion about controlled improvisation and use of the voice as compositional tools. The music consists of three sections scored for 5 voices (lead male vocalist and SATB), flute (doubling tenor saxophone), Bb clarinet (doubling baritone saxophone), violin, cello, piano, electronic keyboard, electric guitar, electric bass, drum set, and percussion.
Date: May 2004
Creator: Bradford, Joshua
Partner: UNT Libraries

The Effects of Rate Contingent Consequences and Charting on Response Rates for Two Children with Autism.

Description: This study investigated the effects of a precision teaching package on response rates of children with autism. Prior to both experiments a preference assessment was conducted to identify high preference activities for each participant. Experiment 1 investigated whether response rates would shift as a function of rate-contingent consequences during an academic task. Different activities were associated with different rates of responding. The experimental package of 1 minute timings, rate contingent consequences, and charting was successful in increasing the rates of responding when the most highly preferred activity was associated with high rates of responding. When the contingencies were switched and the most highly preferred activity was contingent on lower rates of responding, the participant's responding did not decrease. Experiment 2 was an attempt to replicate the results of Experiment 1 using a multiple baseline across tasks. The experimental package was not successful in increasing the rate of responding.
Date: May 2004
Creator: Berman, Christine M.
Partner: UNT Libraries

Transfer of Mand Topographies to Tact Relations and Vice Versa in Two Vocal-Verbal Children with Autism

Description: Skinner (1957) suggested that verbal responses learned as mands are not necessarily emitted in tact relations and vice versa. Previous empirical research has found that newly acquired mands and tacts can be functionally independent. The present study investigated 1) whether novel responses taught in mand relations would be emitted as tacts when opportunity for tacting was presented; 2) whether novel responses taught in tact relations would be emitted as mands when opportunity for manding was presented; and 3) whether the size of pre-experimental mand and tact repertoires affected the rate of acquisition and/or transfer. Two vocal-verbal children with autism were taught three novel responses as mands and three other responses as tacts. Mand topographies transferred to tact relations and tact topographies transferred to mand relations for both participants. Overall acquisition as well as transfer of mands and tacts was faster for the participant with an entering repertoire of approximately 175 mands and 175 tacts than for the participant with a repertoire of approximately 100 mands and 100 tacts.
Date: May 2004
Creator: Castellani, Jill E.
Partner: UNT Libraries

Mary/merry and horse/hoarse: Mergers in Southern American English

Description: Phonetic mergers in American English have been studied throughout the last half century. Previous research has contributed social and phonetic explanations to the understanding of front and back vowel mergers before /l/, front vowel mergers before nasals and phonetically unconditioned back vowel mergers. Using data from the Linguistic Atlas of the Gulf States (LAGS) and the Linguistic Atlas of the Middle and South Atlantic States (LAMSAS), this thesis examines the spread of the front vowel mergers in Mary and merry and the back vowel mergers in horse and hoarse. The two complementary sources of data allow for a social and phonetic approach to the examination of the merger.
Date: May 2004
Creator: Ehrhardt, Brooke
Partner: UNT Libraries