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Toward a More Personally Expressive Method of Working in Clay (open access)

Toward a More Personally Expressive Method of Working in Clay

The goal of this work (entitled: Toward a More Personally Expressive Method of Working in Clay) was to create a body of work that was more personal, expressive, and less restrained that incorporate objects and non- clay elements.
Date: May 1998
Creator: Jacobson, Patricia M.
System: The UNT Digital Library
The Balance of Contradictions: Abstraction and Representation, Formalism and Symbolism (open access)

The Balance of Contradictions: Abstraction and Representation, Formalism and Symbolism

This paper discusses the concept of figurative formalism and its application in six paintings on canvas by the author. Linda Leonhart McCall explores the work of Johannes Vermeer, Edward Hopper, and Richard Diebenkorn in discussing abstraction and representation.
Date: May 1998
Creator: McCall, Linda Leonhart
System: The UNT Digital Library
Body Conscious: Pushing the Boundaries of Traditional Western Adornment (open access)

Body Conscious: Pushing the Boundaries of Traditional Western Adornment

The focus of the problem was to challenge the more traditional. Western approaches to jewelry as adornment in respect to areas such as placement and scale. Approaching adornment as sculptural forms interacting with the human body could possibly challenge the individual's awareness of jewelry as wearable art. This approach brought up the issue of using the human body as a pedestal for adornment.
Date: May 1998
Creator: DeRuiter, Margaret A.
System: The UNT Digital Library
The Visual Perception of Body Language in Sculpture (open access)

The Visual Perception of Body Language in Sculpture

My work attempted to examine the emotional and psychological relationships between humans and the relationship of a human being with their inner self. I adopted the human figure as a potentially successful means of expressing these relationships. The language or symbolism I used in my work was derived directly from body language. This universal language is direct and immediate. Body language, posture, attitude, and tension of the figure are primary perceptions observed by the viewer. The immediacy of communication and directness of emotions through the use of body language were my main concerns. The major issue I dealt with was trying to invest those same emotions into my sculpture. My intention was to endow the sculpture, which consisted of a static unchanging pose and was created from an inert material, with a recognizable emotion and expressiveness that the human figure inherently carries.
Date: May 1998
Creator: Sayago, Maria Sara
System: The UNT Digital Library
Presentation and Preparation: A Survey of Functional Forms (open access)

Presentation and Preparation: A Survey of Functional Forms

While I worked, I made a number of pieces that followed a common theme, each relating to the piece made before and after. This way of working revealed new possibilities for expression. During this particular body of work, I explored a specific series of forms that could be used in the preparation and presentation of food and drink.
Date: May 1998
Creator: Herbst, Frederic
System: The UNT Digital Library
A Successful Union Between Functional and Decorative Pottery (open access)

A Successful Union Between Functional and Decorative Pottery

The goal of this study was to construct a body of work encompassing a broad range of wheel thrown functional pots that are accented with hand built additions. I produced a total of forty pieces developed from four forms representing a respective increase in scale. I addressed technical and aesthetic issues during the process. These included glaze combinations, variations of established hand built additions, surface decoration, and form/shape manipulation.
Date: May 1998
Creator: Peck, Douglas E.
System: The UNT Digital Library
Female (open access)

Female

My objective was to create a body of work using various printing processes. I wanted to communicate my emotional responses to the fertility and childbearing of older women. I wanted to address the realities that become problems for women who wait to have children at an older age and related feelings. Some of these problems were infertility, early menopause, "sticky eggs," and birth defects. There are current medical practices that help these problems such as the freezing of eggs, artificial insemination, and multiple births. I wanted to incorporate ideas about the panic I began to feel about having a child at an older age and my frustration over the lack of open discussion about such feelings. I have combined the use of realism and abstraction in my work. I included dyed and torn paper to lend organic and tactile qualities to the humanistic subject matter. The end result has consisted of various forms of collage and an assembly of the dyed, torn and printed paper.
Date: May 1998
Creator: Conlon, Michaela
System: The UNT Digital Library
Visions and Revisions (open access)

Visions and Revisions

My problem was to develop a personal symbolism within my paintings that expresses my identity. Who am I? Who have I been? Who will I be? Since these paintings are a way of telling my story. One aspect of the problem was communicating my ideas, making the paintings readable. Representational and recognizable images are culturally traceable symbols. The intended reading of the symbols may be generally understood; however, some degree of ambiguity was anticipated since ambiguity is an inherent aspect of symbolism. IN so much as I value symbolism and communicating ideas I believe that ambiguity is equally important. I proposed to balance readability with mystique. Things of the inner self are not immediately evident but found through contemplation. They hold mystery.
Date: May 1998
Creator: Kotzer, Ann Kringe
System: The UNT Digital Library
Shifts of Focus Among Dimensions of User Information Problems as Represented During Interactive Information Retrieval (open access)

Shifts of Focus Among Dimensions of User Information Problems as Represented During Interactive Information Retrieval

The goal of this study is to increase understanding of information problems as they are revealed in interactions among users and search intermediaries during information retrieval. Specifically, this study seeks to investigate: (a) how interaction between users and search intermediaries reveals aspects of user information problems; (b) to explore the concept of representation with respect to information problems in interactive information retrieval; and (c) how user and search intermediaries focus on aspects of user information problems during the course of searches. This project extends research on interactive information retrieval, and presents a theoretical framework that synthesizes rational and non-rational questions concerning mental representation as it pertains to user's understanding of information problems.
Date: May 1998
Creator: Robins, David B. (David Bruce)
System: The UNT Digital Library
A Guide for the Preparation, Analysis and Performance of the Brass Quintet Literature of Thom Ritter George, with Three Recitals of Selected Works by Bach, Bitsch, Handel, Torelli, Suderberg, Ketting and Others (open access)

A Guide for the Preparation, Analysis and Performance of the Brass Quintet Literature of Thom Ritter George, with Three Recitals of Selected Works by Bach, Bitsch, Handel, Torelli, Suderberg, Ketting and Others

An examination of the musical style, compositional techniques and performance practice issues of American composer Thom Ritter George with special attention paid to his Quintet No. 4 written in 1986. The document also includes a short history of brass instruments in chamber music, history of the brass quintet in America, discussion of the role of the trumpet in the quintet, overview of the composers contributions to music and brass quintet in America, discussion of the role of the trumpet in the quintet, overview of the composers contributions to music and brass quintet, and background information on the composer.
Date: May 1998
Creator: Stowman, William J. (William John)
System: The UNT Digital Library
Assessing the Feasibility of Developing a DBAE Curriculum in Qatar Utilizing Multimedia Technology (open access)

Assessing the Feasibility of Developing a DBAE Curriculum in Qatar Utilizing Multimedia Technology

The purpose of this study was to demonstrate the feasibility of developing an art curriculum in Qatar, using the principles of the DBAE curriculum in conjunction with technology. Many of the challenges facing art educators and the art curriculum in Qatar can be approached through the multimedia applications of DBAE, which will provide instructors and students with an opportunity to more readily interact with visual art and to discover its educational relevance. Additionally, this study attempted to discover whether teachers are engaged in implementing technology in the art classroom and whether they are given the opportunity to engage in art to their satisfaction.
Date: May 1998
Creator: Al-Hamad, Wafaa
System: The UNT Digital Library
A Transcription of Three Arias from The Barber of Seville, by Gioacchino Rossini, for Solo Euphonium and Large Brass Ensemble, with Three Recitals of Selected Works by E. Bozza, A. Capuzzi, J. Koetsier, A. Ponchielli, and Others (open access)

A Transcription of Three Arias from The Barber of Seville, by Gioacchino Rossini, for Solo Euphonium and Large Brass Ensemble, with Three Recitals of Selected Works by E. Bozza, A. Capuzzi, J. Koetsier, A. Ponchielli, and Others

Document accompanying a transcription for solo euphonium and large brass ensemble of three arias, "Ecco ridente in cielo," "Largo al factotum," and "A un dottor della mia sorte," from Gioacchino Rossini's opera The Barber of Seville. Includes overviews of the arias' texts and contexts, orchestrational techniques in the transcriptions, the history and definition of the term "euphonium," and the history of the large brass ensemble in the United States.
Date: May 1998
Creator: Pollard, Louis M. (Louis Melvin)
System: The UNT Digital Library
An Epidemiological Survey of Musculoskeletal Pain Among a Self-Selected Population of Organists (open access)

An Epidemiological Survey of Musculoskeletal Pain Among a Self-Selected Population of Organists

The purpose of this study was to investigate problem areas of organists' performance as indicated by common experiences of pain. The research problems were to determine the specific areas of the body that were affected by pain, to determine the perceived level of that pain on a scale indicative of its severity, and to explore the relationship between demographic and performance-related factors within the population and specific area of reported pain. An examination of the demographic, performance-related, and pain data, as well as subject comments, indicated possible relationships of the pain experience to other factors. Organists attributed their pain to instrument characteristics, such as keyboard action, music rack height, bench design, and pedalboard shape. Pain was also associated with the time spent playing the organ, playing literature which required large reaches and rapid passage work, such as french toccatas, or playing with incorrect posture. To explore these relationships to spinal and upper extremity pain, further research is indicated.
Date: May 1998
Creator: Dillard, E. Margo (Edna Margo)
System: The UNT Digital Library
Primarily Thai (open access)

Primarily Thai

This thesis is a production report that describes the research process, pre-production and post-production stages of making a documentary about the Thai language school in the Thai temple in Dallas County. The film documents the teachers from Chulalongkorn University who volunteered to teach Thai-American students in the United States, and explores Thai-American students' attitudes toward the school and their heritage.
Date: May 1998
Creator: Phatthanodom, Fahmui
System: The UNT Digital Library
Advanced far infrared blocked impurity band detectors based on germanium liquid phase epitaxy (open access)

Advanced far infrared blocked impurity band detectors based on germanium liquid phase epitaxy

This research has shown that epilayers with residual impurity concentrations of 5 x 10{sup 13} cm{sup {minus}3} can be grown by producing the purest Pb available in the world. These epilayers have extremely low minority acceptor concentrations, which is ideal for fabrication of IR absorbing layers. The Pb LPE growth of Ge also has the advantageous property of gettering Cu from the epilayer and the substrate. Epilayers have been grown with intentional Sb doping for IR absorption on lightly doped substrates. This research has proven that properly working Ge BIB detectors can be fabricated from the liquid phase as long as pure enough solvents are available. The detectors have responded at proper wavelengths when reversed biased even though the response did not quite reach minimum wavenumbers. Optimization of the Sb doping concentration should further decrease the photoionization energy of these detectors. Ge BIB detectors have been fabricated that respond to 60 cm{sup {minus}1} with low responsivity. Through reduction of the minority residual impurities, detector performance has reached responsivities of 1 A/W. These detectors have exhibited quantum efficiency and NEP values that rival conventional photoconductors and are expected to provide a much more sensitive tool for new scientific discoveries in a …
Date: May 1, 1998
Creator: Olsen, C.S.
System: The UNT Digital Library
The applicability of certain Monte Carlo methods to the analysis of interacting polymers (open access)

The applicability of certain Monte Carlo methods to the analysis of interacting polymers

The authors consider polymers, modeled as self-avoiding walks with interactions on a hexagonal lattice, and examine the applicability of certain Monte Carlo methods for estimating their mean properties at equilibrium. Specifically, the authors use the pivoting algorithm of Madras and Sokal and Metroplis rejection to locate the phase transition, which is known to occur at {beta}{sub crit} {approx} 0.99, and to recalculate the known value of the critical exponent {nu} {approx} 0.58 of the system for {beta} = {beta}{sub crit}. Although the pivoting-Metropolis algorithm works well for short walks (N < 300), for larger N the Metropolis criterion combined with the self-avoidance constraint lead to an unacceptably small acceptance fraction. In addition, the algorithm becomes effectively non-ergodic, getting trapped in valleys whose centers are local energy minima in phase space, leading to convergence towards different values of {nu}. The authors use a variety of tools, e.g. entropy estimation and histograms, to improve the results for large N, but they are only of limited effectiveness. Their estimate of {beta}{sub crit} using smaller values of N is 1.01 {+-} 0.01, and the estimate for {nu} at this value of {beta} is 0.59 {+-} 0.005. They conclude that even a seemingly simple system …
Date: May 1, 1998
Creator: Krapp, D.M. Jr.
System: The UNT Digital Library
Effects of pore fluids in the subsurface on ultrasonic wave propagation (open access)

Effects of pore fluids in the subsurface on ultrasonic wave propagation

This thesis investigates ultrasonic wave propagation in unconsolidated sands in the presence of different pore fluids. Laboratory experiments have been conducted in the sub-MHz range using quartz sand fully saturated with one or two liquids. Elastic wave propagation in unconsolidated granular material is computed with different numerical models: in one-dimension a scattering model based on an analytical propagator solution, in two dimensions a numerical approach using the boundary integral equation method, in three dimensions the local flow model (LFM), the combined Biot and squirt flow theory (BISQ) and the dynamic composite elastic medium theory (DYCEM). The combination of theoretical and experimental analysis yields a better understanding of how wave propagation in unconsolidated sand is affected by (a) homogeneous phase distribution; (b) inhomogeneous phase distribution, (fingering, gas inclusions); (c) pore fluids of different viscosity; (d) wettabilities of a porous medium. The first study reveals that the main ultrasonic P-wave signatures, as a function of the fraction on nonaqueous-phase liquids in initially water-saturated sand samples, can be explained by a 1-D scattering model. The next study investigates effects of pore fluid viscosity on elastic wave propagation, in laboratory experiments conducted with sand samples saturated with fluids of different viscosities. The last study …
Date: May 1, 1998
Creator: Seifert, P.K.
System: The UNT Digital Library
Ultrashort X-ray pulse science (open access)

Ultrashort X-ray pulse science

A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90{sup o} Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated {approx} 300 fs, 30 keV (0.4 {angstrom}) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort …
Date: May 1, 1998
Creator: Chin, Alan H.
System: The UNT Digital Library
Effect of uniaxial stress on gallium, beryllium, and copper-doped germanium hole population inversion lasers (open access)

Effect of uniaxial stress on gallium, beryllium, and copper-doped germanium hole population inversion lasers

The effects of stress on germanium lasers doped with single, double, and triple acceptors have been investigated. The results can be explained quantitatively with theoretical calculations and can be attributed to specific changes in the energy levels of acceptors in germanium under stress. In contrast to previous measurements, gallium-doped Ge crystals show a decrease in lasing upon uniaxial stress. The decrease seen here is attributed to the decrease in heavy hole effective mass upon application of uniaxial stress, which results in a decreased population inversion. The discrepancy between this work and previous studies can be explained with the low compensation level of the material used here. Because the amount of ionized impurity scattering in low-compensated germanium lasers is small to begin with, the reduction in scattering with uniaxial stress does not play a significant role in changing the laser operation. Beryllium-doped germanium lasers operate based on a different mechanism of population inversion. In this material it is proposed that holes can transfer between bands by giving their energy to a neutral beryllium atom, raising the hole from the ground to a bound excited state. The free hole will then return to zero energy with some probability of entering the other …
Date: May 1998
Creator: Chamberlin, D. R.
System: The UNT Digital Library
Naturalness and supersymmetry (open access)

Naturalness and supersymmetry

In this thesis, the author argues that the supersymmetric Standard Model, while avoiding the fine tuning in electroweak symmetry breaking, requires unnaturalness/fine tuning in some (other) sector of the theory. For example, Baryon and Lepton number violating operators are allowed which lead to proton decay and flavor changing neutral currents. He studies some of the constraints from the latter in this thesis. He has to impose an R-parity for the theory to be both natural and viable. In the absence of flavor symmetries, the supersymmetry breaking masses for the squarks and sleptons lead to too large flavor changing neutral currents. He shows that two of the solutions to this problem, gauge mediation of supersymmetry breaking and making the scalars of the first two generations heavier than a few TeV, reintroduce fine tuning in electroweak symmetry breaking. He also constructs a model of low energy gauge mediation with a non-minimal messenger sector which improves the fine tuning and also generates required Higgs mass terms. He shows that this model can be derived from a Grand Unified Theory despite the non-minimal spectrum.
Date: May 1, 1998
Creator: Agashe, K.
System: The UNT Digital Library
The phase space of the focused cubic Schroedinger equation: A numerical study (open access)

The phase space of the focused cubic Schroedinger equation: A numerical study

In a paper of 1988 [41] on statistical mechanics of the nonlinear Schroedinger equation, it was observed that a Gibbs canonical ensemble associated with the nonlinear Schroedinger equation exhibits behavior reminiscent of a phase transition in classical statistical mechanics. The existence of a phase transition in the canonical ensemble of the nonlinear Schroedinger equation would be very interesting and would have important implications for the role of this equation in modeling physical phenomena; it would also have an important bearing on the theory of weak solutions of nonlinear wave equations. The cubic Schroedinger equation, as will be shown later, is equivalent to the self-induction approximation for vortices, which is a widely used equation of motion for a thin vortex filament in classical and superfluid mechanics. The existence of a phase transition in such a system would be very interesting and actually very surprising for the following reasons: in classical fluid mechanics it is believed that the turbulent regime is dominated by strong vortex stretching, while the vortex system described by the cubic Schroedinger equation does not allow for stretching. In superfluid mechanics the self-induction approximation and its modifications have been used to describe the motion of thin superfluid vortices, which …
Date: May 1, 1998
Creator: Burlakov, Y.O.
System: The UNT Digital Library
Production of low axial energy spread ion beams with multicusp sources (open access)

Production of low axial energy spread ion beams with multicusp sources

Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed …
Date: May 1, 1998
Creator: Lee, Y.H.Y.
System: The UNT Digital Library
Time resolved studies of bond activation by organometallic complexes (open access)

Time resolved studies of bond activation by organometallic complexes

In 1971, Jetz and Graham discovered that the silicon-hydrogen bond in silanes could be broken under mild photochemical conditions in the presence of certain transition metal carbonyls. Such reactions fall within the class of oxidative addition. A decade later, similar reactivity was discovered in alkanes. In these cases a C-H bond in non-functionalized alkanes was broken through the oxidative addition of Cp*Ir(H){sub 2}L (Cp* = (CH{sub 3}){sub 5}C{sub 5}, L = PPh{sub 3}, Ph = C{sub 6}H{sub 5}) to form Cp*ML(R)(H) or of Cp*Ir(CO){sub 2} to form Cp*Ir(CO)(R)(H). These discoveries opened an entirely new field of research, one which naturally included mechanistic studies aimed at elucidating the various paths involved in these and related reactions. Much was learned from these experiments but they shared the disadvantage of studying under highly non-standard conditions a system which is of interest largely because of its characteristics under standard conditions. Ultrafast time-resolved IR spectroscopy provides an ideal solution to this problem; because it allows the resolution of chemical events taking place on the femto-through picosecond time scale, it is possible to study this important class of reactions under the ambient conditions which are most of interest to the practicing synthetic chemist. Certain of the …
Date: May 1, 1998
Creator: Wilkens, M. J.
System: The UNT Digital Library
The influence of surface topography on the forming friction of automotive aluminum sheet (open access)

The influence of surface topography on the forming friction of automotive aluminum sheet

Interest in utilizing aluminum alloys in automobiles has increased in recent years as a result of the desire to lower automobile weight and, consequently, increase fuel economy. While aluminum alloy use in cast parts has increased, outer body panel applications are still being investigated. The industry is interested in improving the formability of these sheet alloys by a combination of alloy design and processing. A different avenue of improving the formability of these alloys may be through patterning of the sheet surface. Surface patterns hold the lubricant during the forming process, with a resulting decrease in the sheet-die surface contact. While it has been speculated that an optimum surface pattern would consist of discrete cavities, detailed investigation into the reduction of forming friction by utilizing discrete patterns is lacking. A series of discrete patterns were investigated to determine the dependence of the forming friction of automotive aluminum alloys on pattern lubricant carrying capacity and on material strength. Automotive aluminum alloys used in outer body panel applications were rolled on experimental rolls that had been prepared with a variety of discrete patterns. All patterns for each alloy were characterized before and after testing both optically and, to determine pattern lubricant capacity, …
Date: May 1, 1998
Creator: Kramer, P. A.
System: The UNT Digital Library