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Religion as a Factor in the Literary Career of Nathaniel Hawthorne (open access)

Religion as a Factor in the Literary Career of Nathaniel Hawthorne

The purpose of this study is to evaluate various religious elements in Nathainel Hawthorne's life in relation to his career as a literary artist. The moral seriousness of this author at once strikes us as being something closely akin to religious sentiment, but he refused to endorse any specific dogma or to subscribe to any one organized faith. We know from his work that he had a religion, but his silence leaves ample room for conjecture if we wish to "label" him, or decide which of those religions that he contemplated was most congenial to his nature.
Date: July 1952
Creator: Miller, John Davidson
System: The UNT Digital Library
An Experimental Technique for the Objective Quantification of Body-Image Distortion (open access)

An Experimental Technique for the Objective Quantification of Body-Image Distortion

The purpose of this study was to develop an experimental technique to objectively measure the deviation between an individual's perception of his body image and his actual image. In addition, this technique was utilized to compare the accuracy of perception of body image between institutionalized and non-institutionalized individuals. Half of each subject category was also compared in terms of performance on an additional perceptual task unrelated to body image.
Date: July 1971
Creator: Lemon, James M.
System: The UNT Digital Library
Well Wishers and Donut Worshipers (open access)

Well Wishers and Donut Worshipers

Short story written by a student in the UNT Honors College that features Merlin the wizard and other magical occurrences in modern day America.
Date: July 1994
Creator: Robinson, Jennifer
System: The UNT Digital Library
Andrew Johnson and the South, 1865-1867 (open access)

Andrew Johnson and the South, 1865-1867

The purpose of this dissertation is to examine the relationship of Andrew Johnson to the South and the effect of that relationship on presidential reconstruction. It is not meant to be a complete retelling of the story of reconstruction, rather it is an attempt to determine how Johnson affected southern ideas of reconstruction and, equally important, how southerners influenced Johnson.
Date: July 1970
Creator: Pierce, Michael D. (Michael Dale), 1940-
System: The UNT Digital Library
The Teaching Practices of Science Teachers in Selected Texas High Schools (open access)

The Teaching Practices of Science Teachers in Selected Texas High Schools

The problem of this study was to determine the emphasis placed on various science teaching practices by a random sample of high school biology, chemistry, and physics teachers in selected Texas high schools. The subproblem was to compare the emphasis placed on the practices as reported by the high school teachers with the emphasis as recommended by national science education specialists, teachers of biology, chemistry, and physics in selected Texas colleges and universities, and teachers of professional education courses in selected Texas colleges and universities.
Date: July 1967
Creator: Pewitt, Edith Marie Hendrix
System: The UNT Digital Library
The Effects of Computer Performance Assessment on Student Scores in a Computer Applications Course (open access)

The Effects of Computer Performance Assessment on Student Scores in a Computer Applications Course

The goal of this study was to determine if performance-based tests should be routinely administered to students in computer application courses. The purpose was to determine the most appropriate mode of testing for individuals taking a computer applications course. The study is divided into areas of assessment, personality traits, and computer attitudes.
Date: July 1994
Creator: Casey, Sue Hartness
System: The UNT Digital Library
Spatiotemporal Properties of Coupled Nonlinear Oscillators (open access)

Spatiotemporal Properties of Coupled Nonlinear Oscillators

Spatiotemporal properties of classical coupled nonlinear oscillators are investigated in this thesis. Chapter 1 gives an introduction to nonlinear lattices and to the concept of breathers, that are spatially localized and temporally periodic excitation in nonlinear lattices. The concept of anti-continuous limit that provides the basic methodology in probing spatiotemporal breather properties is discussed. In Chapter 2, the general approach for finding exact breather solutions from the anti-continuous limit is examined, and the rotating wave approximation(RWA) is applied to probe the spatial structure of static breathers. Numerical evidence reveals that the RWA relates the spatial structure of stable multi-breathers to a single breather of the same frequency. Chapter 3 presents linear stability analysis of static breathers and gives a systematic way to construct mobile breathers. Formation and collision properties of this moving breathers are also studied. Chapter 4 discusses dynamics of kinks and anti-kinks in hydrogen-bonded chains in the context of two-component soliton model. From molecular dynamics simulations with finite temperature, it is observed that, in a real system (eg. ice), a pair of kink and anti-kink can evolve into a moving-breather-like excitation. Chapter 5 is devoted to the understand of the effects of disorder in the Holstein model. The …
Date: July 1996
Creator: Chen, Ding
System: The UNT Digital Library
A Study of the Relationships among Student Expectations about Teacher Nonverbal Immediacy, Student Perceptions of Teacher Nonverbal Immediacy, and Affective Learning in Distance Learning and the On-Site Classroom (open access)

A Study of the Relationships among Student Expectations about Teacher Nonverbal Immediacy, Student Perceptions of Teacher Nonverbal Immediacy, and Affective Learning in Distance Learning and the On-Site Classroom

This thesis explored the relationships among three communication variables in college-level instruction: students' expectancy about teachers' nonverbal immediacy, students' actual perceptions of teachers' nonverbal immediacy, and students' affective learning. Community college students enrolled in either distance learning or a traditional classroom course completed pre-course and mid-course questionnaires to indicate their expectations and observations of the nonverbal immediacy behaviors of their teachers. Analysis showed that students expected and perceived less nonverbal immediacy from tele-course teachers than from on-site teachers, but that perceptions significantly exceeded expectations. Research findings indicated that students' expectancies about teachers' nonverbal immediacy may influence the measurement of affective learning.
Date: July 1997
Creator: Witt, Paul L.
System: The UNT Digital Library
The effects of computer performance assessment on student scores in a computer applications course (open access)

The effects of computer performance assessment on student scores in a computer applications course

The goal of this study was to determine if performance -based tests should be routinely administered to students in computer application courses. The purpose was to determine the most appropriate mode of testing for individuals taking a computer applications course. The study is divided into areas of assessment, personality traits, and computer attitudes.
Date: July 1994
Creator: Casey, Sue Hartness
System: The UNT Digital Library
A Machine Learning Method Suitable for Dynamic Domains (open access)

A Machine Learning Method Suitable for Dynamic Domains

The efficacy of a machine learning technique is domain dependent. Some machine learning techniques work very well for certain domains but are ill-suited for other domains. One area that is of real-world concern is the flexibility with which machine learning techniques can adapt to dynamic domains. Currently, there are no known reports of any system that can learn dynamic domains, short of starting over (i.e., re-running the program). Starting over is neither time nor cost efficient for real-world production environments. This dissertation studied a method, referred to as Experience Based Learning (EBL), that attempts to deal with conditions related to learning dynamic domains. EBL is an extension of Instance Based Learning methods. The hypothesis of the study related to this research was that the EBL method would automatically adjust to domain changes and still provide classification accuracy similar to methods that require starting over. To test this hypothesis, twelve widely studied machine learning datasets were used. A dynamic domain was simulated by presenting these datasets in an uninterrupted cycle of train, test, and retrain. The order of the twelve datasets and the order of records within each dataset were randomized to control for order biases in each of ten runs. …
Date: July 1996
Creator: Rowe, Michael C. (Michael Charles)
System: The UNT Digital Library
The Use of the Power Method to Find Dominant Eigenvalues of Matrices (open access)

The Use of the Power Method to Find Dominant Eigenvalues of Matrices

This paper is the result of a study of the power method to find dominant eigenvalues of square matrices. It introduces ideas basic to the study and shows the development of the power method for the most well-behaved matrices possible, and it explores exactly which other types of matrices yield to the power method. The paper also discusses a type of matrix typically considered impossible for the power method, along with a modification of the power method which works for this type of matrix. It gives an overview of common extensions of the power method. The appendices contain BASIC versions of the power method and its modification.
Date: July 1992
Creator: Cavender, Terri A.
System: The UNT Digital Library
A.B. Marx's Concept of Rondo and Sonata: A Critical Evaluation of His Explanations of Musical Form (open access)

A.B. Marx's Concept of Rondo and Sonata: A Critical Evaluation of His Explanations of Musical Form

The third volume of A.B. Marx's theory treatise Die Lehre von der musikalischen Komposition is discussed. His definitions of rondo and sonata formal types are demonstrated in the first chapter in addition to the manner of their derivation through a developmental process originating in the Liedform. Musical examples chosen by Marx are examined in chapter two. These examples, taken from Mozart's and Beethoven's piano works, are evaluated in relation to Marx's definitions of the various types of form. The third chapter is concerned with the progression from microstructure to macrostructure and the functional interrelation of the parts to the whole. In addition, Marx's opinion on musical form is compared with perspectives of philosophers from his time period and the immediate past.
Date: July 1993
Creator: Lang, Adelheid K.
System: The UNT Digital Library
Acculturation and Locus Of Control: Their Relationship to the Use of Inhalants (open access)

Acculturation and Locus Of Control: Their Relationship to the Use of Inhalants

This study analyzed the effects of acculturation, locus of control, and incidence of inhalant use on Mexican Americans. Information was collected from 275 subjects at three middle schools and one treatment center. The instrument consisted of Levenson's Locus of Control Scale, the Acculturation Rating Scale for Mexican Americans, and an incidence of use and family relationship questionnaire developed for this study. Statistical analysis indicated a relationship between acculturation and inhalant use. Further examination revealed relationships between a family members' use and subjects' inhalant use; subjects' alcohol use and inhalant use; and subjects' marijuana use and inhalant use. Information implied that prevention and intervention programs should focus on children of substance users and further research is needed surrounding the role of acculturation.
Date: July 1989
Creator: Davis, Lynn Matthew
System: The UNT Digital Library
The Chlorination of Amino Acid in Municipal Waste Effluents (open access)

The Chlorination of Amino Acid in Municipal Waste Effluents

In model reaction systems to test amino acids in chlorinated waste effluents, several amino acids were chlorinated at high chlorine doses. (2000-4000 mg/1). Amino acids present in municipal waste effluents before and after chlorination were concentrated and purified using cation exchange and Chelex resins. After concentration and cleanup of the samples, the amino acids were derivatized by esterification of the acid functional groups and acylation of the amine groups. Identification and quantification of the amino acids and chlorination products was carried out by gas chromatography/mass spectrometry, using a digital computer data system. Analysis of the waste products revealed the presence of new carbon-chlorine bonded derivatives of the amino acid tyrosine when the effluents were treated with heavy doses of chlorine.
Date: July 1977
Creator: Burleson, Jimmie L.
System: The UNT Digital Library
Transport and sorption of volatile organic compounds and water vapor in porous media (open access)

Transport and sorption of volatile organic compounds and water vapor in porous media

To gain insight on the controlling mechanisms for VOC transport in porous media, the relations among sorbent properties, sorption equilibrium and intraparticle diffusion processes were studied at the level of individual sorbent particles and laboratory columns for soil and activated carbon systems. Transport and sorption of VOCs and water vapor were first elucidated within individual dry soil mineral grains. Soil properties, sorption capacity, and sorption rates were measured for 3 test soils; results suggest that the soil grains are porous, while the sorption isotherms are nonlinear and adsorption-desorption rates are slow and asymmetric. An intragranular pore diffusion model coupled with the nonlinear Freundlich isotherm was developed to describe the sorption kinetic curves. Transport of benzene and water vapor within peat was studied; partitioning and sorption kinetics were determined with an electrobalance. A dual diffusion model was developed. Transport of benzene in dry and moist soil columns was studied, followed by gaseous transport and sorption in activated carbon. The pore diffusion model provides good fits to sorption kinetics for VOCs to soil and VOC to granular activated carbon and activated carbon fibers. Results of this research indicate that: Intraparticle diffusion along with a nonlinea sorption isotherm are responsible for the slow, …
Date: July 1, 1995
Creator: Lin, Tsair-Fuh
System: The UNT Digital Library
Effects of Actinide Burning on Waste Disposal at Yucca Mountain (open access)

Effects of Actinide Burning on Waste Disposal at Yucca Mountain

Release rates of 15 radionuclides from waste packages expected to result from partitioning and transmutation of Light-Water Reactor (LWR) and Actinide-Burning Liquid-Metal Reactor (ALMR) spent fuel are calculated and compared to release rates from standard LWR spent fuel packages. The release rates are input to a model for radionuclide transport from the proposed geologic repository at Yucca Mountain to the water table. Discharge rates at the water table are calculated and used in a model for transport to the accessible environment, defined to be five kilometers from the repository edge. Concentrations and dose rates at the accessible environment from spent fuel and wastes from reprocessing, with partitioning and transmutation, are calculated. Partitioning and transmutation of LWR and ALMR spent fuel reduces the inventories of uranium, neptunium, plutonium, americium and curium in the high-level waste by factors of 40 to 500. However, because release rates of all of the actinides except curium are limited by solubility and are independent of package inventory, they are not reduced correspondingly. Only for curium is the repository release rate much lower for reprocessing wastes.
Date: July 1, 1992
Creator: Hirschfelder, J.
System: The UNT Digital Library
NMR investigations of surfaces and interfaces using spin-polarized xenon (open access)

NMR investigations of surfaces and interfaces using spin-polarized xenon

{sup 129}Xe NMR is potentially useful for the investigation of material surfaces, but has been limited to high surface area samples in which sufficient xenon can be loaded to achieve acceptable signal to noise ratios. In Chapter 2 conventional {sup 129}Xe NMR is used to study a high surface area polymer, a catalyst, and a confined liquid crystal to determine the topology of these systems. Further information about the spatial proximity of different sites of the catalyst and liquid crystal systems is determined through two dimensional exchange NMR in Chapter 3. Lower surface area systems may be investigated with spin-polarized xenon, which may be achieved through optical pumping and spin exchange. Optically polarized xenon can be up to 10{sup 5} times more sensitive than thermally polarized xenon. In Chapter 4 highly polarized xenon is used to examine the surface of poly(acrylonitrile) and the formation of xenon clathrate hydrates. An attractive use of polarized xenon is as a magnetization source in cross polarization experiments. Cross polarization from adsorbed polarized xenon may allow detection of surface nuclei with drastic enhancements. A non-selective low field thermal mixing technique is used to enhance the {sup 13}C signal of CO{sub 2} of xenon occluded in …
Date: July 1, 1995
Creator: Gaede, H.C.
System: The UNT Digital Library
Synthesis, characterization and application of electrode materials (open access)

Synthesis, characterization and application of electrode materials

It has been known that significant advances in electrochemistry really depend on improvements in the sensitivity, selectivity, convenience, and/or economy of working electrodes, especially through the development of new working electrode materials. The advancement of solid state chemistry and materials science makes it possible to provide the materials which may be required as satisfactory electrode materials. The combination of solid state techniques with electrochemistry expands the applications of solid state materials and leads to the improvement of electrocatalysis. The study of Ru-Ti{sub 4}O{sub 7} and Pt-Ti{sub 4}O{sub 7} microelectrode arrays as introduced in paper 1 and paper 4, respectively, focuses on their synthesis and characterization. The synthesis is described by high temperature techniques for Ru or Pt microelectrode arrays within a conductive Ti{sub 4}O{sub 7} ceramic matrix. The characterization is based on the data obtained by x-ray diffractometry, scanning electron microscopy, voltammetry and amperometry. These microelectrode arrays show significant enhancement in current densities in comparison to solid Ru and Pt electrodes. Electrocatalysis at pyrochlore oxide Bi{sub 2}Ru{sub 2}O{sub 7.3} and Bi{sub 2}Ir{sub 2}O{sub 7} electrodes are described in paper 2 and paper 3, respectively. Details are reported for the synthesis and characterization of composite Bi{sub 2}Ru{sub 2}O{sub 7.3} electrodes. Voltammetric …
Date: July 7, 1995
Creator: He, L.
System: The UNT Digital Library
Matrix effects in inductively coupled plasma mass spectrometry (open access)

Matrix effects in inductively coupled plasma mass spectrometry

The inductively coupled plasma is an electrodeless discharge in a gas (usually Ar) at atmospheric pressure. Radio frequency energy generated by a RF power source is inductively coupled to the plasma gas through a water cooled load coil. In ICP-MS the {open_quotes}Fassel{close_quotes} TAX quartz torch commonly used in emission is mounted horizontally. The sample aerosol is introduced into the central flow, where the gas kinetic temperature is about 5000 K. The aerosol is vaporized, atomized, excited and ionized in the plasma, and the ions are subsequently extracted through two metal apertures (sampler and skimmer) into the mass spectrometer. In ICP-MS, the matrix effects, or non-spectroscopic interferences, can be defined as the type of interferences caused by dissolved concomitant salt ions in the solution. Matrix effects can be divided into two categories: (1) signal drift due to the deposition of solids on the sampling apertures; and/or (2) signal suppression or enhancement by the presence of the dissolved salts. The first category is now reasonably understood. The dissolved salts, especially refractory oxides, tend to deposit on the cool tip of the sampling cone. The clogging of the orifices reduces the ion flow into the ICP-MS, lowers the pressure in the first stage …
Date: July 7, 1995
Creator: Chen, Xiaoshan
System: The UNT Digital Library
Igniting the Light Elements: The Los Alamos Thermonuclear Weapon Project, 1942-1952 (open access)

Igniting the Light Elements: The Los Alamos Thermonuclear Weapon Project, 1942-1952

The American system of nuclear weapons research and development was conceived and developed not as a result of technological determinism, but by a number of individual architects who promoted the growth of this large technologically-based complex. While some of the technological artifacts of this system, such as the fission weapons used in World War II, have been the subject of many historical studies, their technical successors--fusion (or hydrogen) devices--are representative of the largely unstudied highly secret realms of nuclear weapons science and engineering. In the postwar period a small number of Los Alamos Scientific Laboratory's staff and affiliates were responsible for theoretical work on fusion weapons, yet the program was subject to both the provisions and constraints of the US Atomic Energy Commission, of which Los Alamos was a part. The Commission leadership's struggle to establish a mission for its network of laboratories, least of all to keep them operating, affected Los Alamos's leaders' decisions as to the course of weapons design and development projects. Adapting Thomas P. Hughes's ''large technological systems'' thesis, I focus on the technical, social, political, and human problems that nuclear weapons scientists faced while pursuing the thermonuclear project, demonstrating why the early American thermonuclear bomb …
Date: July 1, 1999
Creator: Fitzpatrick, Anne C.
System: The UNT Digital Library
Bis(pentamethylcyclopentadienyl)ytterbium: An investigation of weak interactions in solution using multinuclear NMR spectroscopy (open access)

Bis(pentamethylcyclopentadienyl)ytterbium: An investigation of weak interactions in solution using multinuclear NMR spectroscopy

NMR spectroscopy is ideal for studying weak interactions (formation enthalpy {le}20 kcal/mol) in solution. The metallocene bis(pentamethylcyclopentadienyl)ytterbium, Cp*{sub 2}Yb, is ideal for this purpose. cis-P{sub 2}PtH{sub 2}complexes (P = phosphine) were used to produce slow-exchange Cp*{sub 2}YbL adducts for NMR study. Reversible formation of (P{sub 2}PtH){sub 2} complexes from cis-P{sub 2}PtH{sub 2} complexes were also studied, followed by interactions of Cp*{sub 2}Yb with phosphines, R{sub 3}PX complexes. A NMR study was done on the interactions of Cp*{sub 2}Yb with H{sub 2}, CH{sub 4}, Xe, CO, silanes, stannanes, C{sub 6}H{sub 6}, and toluene.
Date: July 1, 1995
Creator: Schwartz, D.J.
System: The UNT Digital Library
Nonequilibrium flows with smooth particle applied mechanics (open access)

Nonequilibrium flows with smooth particle applied mechanics

Smooth particle methods are relatively new methods for simulating solid and fluid flows through they have a 20-year history of solving complex hydrodynamic problems in astrophysics, such as colliding planets and stars, for which correct answers are unknown. The results presented in this thesis evaluate the adaptability or fitness of the method for typical hydrocode production problems. For finite hydrodynamic systems, boundary conditions are important. A reflective boundary condition with image particles is a good way to prevent a density anomaly at the boundary and to keep the fluxes continuous there. Boundary values of temperature and velocity can be separately controlled. The gradient algorithm, based on differentiating the smooth particle expression for (u{rho}) and (T{rho}), does not show numerical instabilities for the stress tensor and heat flux vector quantities which require second derivatives in space when Fourier`s heat-flow law and Newton`s viscous force law are used. Smooth particle methods show an interesting parallel linking to them to molecular dynamics. For the inviscid Euler equation, with an isentropic ideal gas equation of state, the smooth particle algorithm generates trajectories isomorphic to those generated by molecular dynamics. The shear moduli were evaluated based on molecular dynamics calculations for the three weighting functions, …
Date: July 1, 1995
Creator: Kum, O.
System: The UNT Digital Library
RHEED studies of the nucleation, growth, and mobility of Ag atoms on the Si(111)7 x 7 surface (open access)

RHEED studies of the nucleation, growth, and mobility of Ag atoms on the Si(111)7 x 7 surface

The low temperature and flux dependent growth of ultrathin Ag films on the Si(111)7x7 surface is studied with Reflection High-Energy Electron Diffraction (RHEED). The grazing incidence geometry of RHEED allows for an incident molecular beam normal to the surface, and makes it an ideal surface probe for studying ultrathin film growth in real time. Short-lived oscillations in the diffracted intensity are observed during Ag deposition at 150 K, indicating quasi-layer-by-layer growth mediated by adatom mobility. When the 150 K growth is performed over a wide range of deposition rates F, the peak intensity is observed to scale, i.e. I(Ft) depends only on the total amount deposited, which implies thermally activated diffusion is absent at 150 K. Scaling is not obeyed at higher temperatures (T{ge}473 K) for the growth of the {radical}3{times}{radical}3 R30{degrees} ({radical}3) superstructure. Testing for scaling of the diffracted intensity constitutes a new experimental method which can be applied generally to determine if thermal diffusion is active at a particular temperature. Scaling is consistent with a constant diffusion length R{sub 0}, independent of substrate temperature and deposition rate. The presence of a non-thermal diffusion mechanism (responsible for the constant diffusion length R{sub 0}) is confirmed by monitoring the flux …
Date: July 1, 1993
Creator: Roos, Kelly Ryan
System: The UNT Digital Library
An Analytical Critique of the Use of Twelve Equal Tones as Utilized in "Sonata-Fantasia" by George Rochberg (open access)

An Analytical Critique of the Use of Twelve Equal Tones as Utilized in "Sonata-Fantasia" by George Rochberg

This thesis centers around a certain twentieth-century compositionaI device, the method of composition with twelve tones. There are many terms to designate this device, for example: "basic set," "tone-row," "note-series," "serialism," "serial technique," "twelve-note series," "twelve-tone technique" or "twelve-tone method." TI is thesis is a methodical research demonstrating the contemporary conventional way of scientifically and artfully manipulating twelve equal tempered degrees of the chromatic scale to produce a desirable system. In order to arrive at any substantial conclusions, it is necessary to make a critical examination and evaluation of known twelve-tone compositional procedures from as many angles as possible, so as virtually to exhaust every practical and speculative potentiality included in the technique, that is, within the range and limits of our present needs. This examination and evaluation will also involve a comparative investigation of various uses of the device, in order to produce and suggest ideas for further theoretical insights. The ultimate purpose of this thesis is to pinpoint the "hows" and "whys" of Rochberg's use of the twelve equal tones in Sonata-Fantasia.
Date: July 1968
Creator: Tiroff, Philip Knight
System: The UNT Digital Library