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Thesis written by a student in the UNT Honors College discussing the relationship between teachers, other teachers, and students and how that relates to teacher satisfaction.

The Matteucci effect, which mainly manifests itself as the change of magnetization of a material with torsional stress, is currently of great technological interest because of the search for magnetic torque sensors. Magnetic torque sensors are important to future improvements of automobiles and industrial robots. It is well known that the magnetic state of a material depends on both the external magnetic field and external stress which causes strain and change in magnetization of the material. The former phenomenon has been well understood in both theory and application. However, the magnetic state dependence of stress is not adequately understood and the experimental data is of limited extent. In this project, the Matteucci effect in iron, cobalt, nickel and permalloy rods has been documented when they were in magnetic remanence status along the axis and nickel ring when they were in remanence status along the circumference. The effect of annealing on the magnetomechanical effect in nickel and the temperature dependence of the magnetomechanical sensitivity has also been examined. Factors related to the sensitivity at equilibrium condition have been theoretically developed. it is found in the experiments that the mechanism of magnetic domain wall movement plays an important role rather than the …

Organic light emitting devices (OLEDs) are among the most promising for flat panel display technologies. They are light, bright, flexible, and cost effective. And while they are emerging in commercial product, their low power efficiency and long-term degradation are still challenging. The aim of this work was to investigate their device physics and improve their performance. Violet and blue OLEDs were studied. The devices were prepared by thermal vapor deposition in high vacuum. The combinatorial method was employed in device preparation. Both continuous wave and transient electroluminescence (EL) were studied. A new efficient and intense UV-violet light emitting device was developed. At a current density of 10 mA/cm{sup 2}, the optimal radiance R could reach 0.38 mW/cm{sup 2}, and the quantum efficiency was 1.25%. using the delayed EL technique, electron mobilities in DPVBi and CBP were determined to be {approx} 10{sup -5} cm{sup 2}/Vs and {approx} 10{sup -4} cm{sup 2}/Vs, respectively. Overshoot effects in the transient El of blue light emitting devices were also observed and studied. This effect was attributed to the charge accumulation at the organic/organic and organic/cathode interfaces.

Organic light-emitting devices (OLEDs) constitute a new and exciting emissive display technology. In general, the basic OLED structure consists of a stack of fluorescent organic layers sandwiched between a transparent conducting-anode and metallic cathode. When an appropriate bias is applied to the device, holes are injected from the anode and electrons from the cathode; some of the recombination events between the holes and electrons result in electroluminescence (EL). Until now, most of the efforts in developing OLEDs have focused on display applications, hence on devices within the visible range. However some organic devices have been developed for ultraviolet or infrared emission. Various aspects of the device physics of doped small molecular OLEDs were described and discussed. The doping layer thickness and concentration were varied systematically to study their effects on device performances, energy transfer, and turn-off dynamics. Low-energy-gap DCM2 guest molecules, in either {alpha}-NPD or DPVBi host layers, are optically efficient fluorophores but also generate deep carrier trap-sites. Since their traps reduce the carrier mobility, the current density decreases with increased doping concentration. At the same time, due to efficient energy transfer, the quantum efficiency of the devices is improved by light doping or thin doping thickness, in comparison with …

This dissertation describes the efforts to design and implement the Generalized Portable SHMEM library, GPSHMEM, as well as supplementary tools. There are two major components of the GPSHMEM project: the GPSHMEM library itself and the Fortran 77 source-to-source translator. The rest of this thesis is divided into two parts. Part I introduces the shared memory model and the distributed shared memory model. It explains the motivation behind GPSHMEM and presents its functionality and performance results. Part II is entirely devoted to the Fortran 77 translator call fgpp. The need for such a tool is demonstrated, functionality goals are stated, and the design issues are presented along with the development of the solutions.

Capillary electrophoresis (CE) offers many advantages over conventional analytical methods, such as speed, simplicity, high resolution, low cost, and small sample consumption, especially for the separation of enantiomers. However, chiral method developments still can be time consuming and tedious. They designed a comprehensive enantioseparation protocol employing neutral and sulfated cyclodextrins as chiral selectors for common basic, neutral, and acidic compounds with a 96-capillary array system. By using only four judiciously chosen separation buffers, successful enantioseparations were achieved for 49 out of 54 test compounds spanning a large variety of pKs and structures. Therefore, unknown compounds can be screened in this manner to identify optimal enantioselective conditions in just one rn. In addition to superior separation efficiency for small molecules, CE is also the most powerful technique for DNA separations. Using the same multiplexed capillary system with UV absorption detection, the sequence of a short DNA template can be acquired without any dye-labels. Two internal standards were utilized to adjust the migration time variations among capillaries, so that the four electropherograms for the A, T, C, G Sanger reactions can be aligned and base calling can be completed with a high level of confidence. the CE separation of DNA can be …

The work presented in this dissertation has investigated three distinct areas of interest in the field of quasicrystals: bulk structure, transport properties, and electronic structure. First, they have described the results of a study which explored the fundamental interactions between the atomic species of the icosahedral Al-Pd-Mn quasicrystal. The goal of this work was to determine whether the pseudo-MacKay or Bergman type clusters have a special stability or are merely a geometric coincidence. This was carried out by using laser vaporization to produce gas-phase metal clusters, which were analyzed using time-of-flight mass spectrometry. Both the kinetic and thermodynamic stabilities of the clusters were probed. The data indicated no special stability for either pseudo-MacKay or Bergman type clusters as isolated units. This, however, is not proof that these clusters are simply a geometric coincidence. It is possible that such clusters only have stability in the framework of the bulk matrix and do not exist as isolated units. Next, they have reported their investigations of the bulk thermal transport properties of a decagonal Al-Ni-Co two dimensional quasicrystal in the temperature range 373K-873K. The properties of a sample oriented along the periodic axis and another oriented along the aperiodic axis were measured. A …

The oxidation resistance of a high-temperature alloy is dependent upon sustaining the formation of a protective scale, which is strongly related to the alloying composition and the oxidation condition. The protective oxide scale only provides a finite period of oxidation resistance owing to its eventual breakdown, which is especially accelerated under thermal cycling conditions. This current study focuses on the long-term cyclic oxidation behavior of a number of commercial wrought alloys. The alloys studied were Fe- and Ni-based, containing different levels of minor elements, such as Si, Al, Mn, and Ti. Oxidation testing was conducted at 1000 and 1100 C in still air under both isothermal and thermal cycling conditions (1-day and 7-days). The specific aspects studied were the oxidation behavior of chromia-forming alloys that are used extensively in industry. The current study analyzed the effects of alloying elements, especially the effect of minor element Si, on cyclic oxidation resistance. The behavior of oxide scale growth, scale spallation, subsurface changes, and chromium interdiffusion in the alloy were analyzed in detail. A novel model was developed in the current study to predict the life-time during cyclic oxidation by simulating oxidation kinetics and chromium interdiffusion in the subsurface of chromia-forming alloys.

Two ionic and one neutral methyl(oxo)rhenium(V) compounds were synthesized and structurally characterized. They were compared in reactivity towards the ligands triphenylphosphane, pyridines, pyridine N-oxides. Assistance from Broensted bases was found on ligand displacement of ionic rhenium compounds as well as nucleophile assistance on oxidation of all compounds. From the kinetic data, crystal structures, and an analysis of the intermediates, a structural formula of PicH{sup +}3{sup -} and mechanisms of ligand displacement and oxidation were proposed.

The scientific community has recently experienced an overall effort to reduce the physical size of many experimental components to the nanometer size range. This size is unique as the characteristics of this regime involve aspects of pure physics, biology, and chemistry. One extensively studied example of a nanometer sized experimental component, which acts as a junction between these three principle scientific theologies, is deoxyribonucleic acid (DNA) or ribonucleic acid (RNA). These biopolymers not only contain the biological genetic guide to code for the production of life-sustaining materials, but are also being probed by physicists as a means to create electrical circuits and furthermore as controllable architectural and sensor motifs in the chemical disciplines. Possibly the most common nano-sized component between these sciences are nanoparticles composed of a variety of materials. The cross discipline employment of nanoparticles is evident from the vast amount of literature that has been produced from each of the individual communities within the last decade. Along these cross-discipline lines, this dissertation examines the use of several different types of nanoparticles with a wide array of surface chemistries to understand their adsorption properties and to construct unique miniaturized analytical and immunoassay platforms. This introduction will act as a …

A magnetic tunnel junction is a device that changes its electrical resistance with a change in an applied magnetic field. A typical junction consists of two magnetic electrodes separated by a nonmagnetic insulating layer. The magnetizations of the two electrodes can have two possible extreme configurations, parallel and antiparallel. The antiparallel configuration is observed to have the higher measured resistance and the parallel configuration has the lower resistance. To switch between these two configurations a magnetic field is applied to the device which is primarily used to change the orientation of the magnetization of one electrode usually called the free layer, although with sufficient high magnetic field the orientation of the magnetizations of both of the electrodes can be changed. The most commonly used models for describing and explaining the electronic behavior of tunnel junctions are the Simmons model and the Brinkman model. However, both of these models were designed for simple, spin independent tunneling. The Simmons model does not address the issue of applied magnetic fields nor does it address the form of the electronic band structure in the metallic electrodes, including the important factor of spin polarization. The Brinkman model is similar, the main difference between the two …

CFD (Computational Fluid Dynamics) is a widely used technique in engineering design field. It uses mathematical methods to simulate and predict flow characteristics in a certain physical space. Since the numerical result of CFD computation is very hard to understand, VR (virtual reality) and data visualization techniques are introduced into CFD post-processing to improve the understandability and functionality of CFD computation. In many cases CFD datasets are very large (multi-gigabytes), and more and more interactions between user and the datasets are required. For the traditional VR application, the limitation of computing power is a major factor to prevent visualizing large dataset effectively. This thesis presents a new system designing to speed up the traditional VR application by using parallel computing and distributed computing, and the idea of using hand held device to enhance the interaction between a user and VR CFD application as well. Techniques in different research areas including scientific visualization, parallel computing, distributed computing and graphical user interface designing are used in the development of the final system. As the result, the new system can flexibly be built on heterogeneous computing environment, dramatically shorten the computation time.

A genomic clone containing a 16.9-kb segment of cotton DNA was found to encompass a D-12 fatty acid desaturases (FAD2-4) gene. The FAD2-4 gene has a single, large intron of 2,780 bp in its 5'-untranslated region, just 12 bp upstream from the ATG initiation codon of the FAD2-4 opening reading frame. A number of prospective promoter elements, including several light-responsive sequences, occur in the 5'-flanking region. The coding region of the gene is 1155 bp with no introns, and would encode a FAD2-4 polypeptide of 384 amino acids. The putative protein had four membrane-spanning helices, hallmarks of an integral membrane protein, and would probably be located in the endoplasmic reticulum. The FAD2-4 gene is indeed a functional gene, since yeast cells transformed with a plasmid containing the coding region of the gene synthesize an appreciable amount of linoleic acid (18:2), not normally made in wild-type yeast cells. The FAD2-4 gene has many structural similarities to the cotton FAD2-3 gene that was also analyzed in this laboratory.

The dissertation focuses on Joe Lovano's utilization of thematic material in relation to "Misterioso" by Thelonius Monk. Thematicism is defined more broadly in this study to include reference to the form, phrase structure, and harmony of "Misterioso". Methodological models provided by Gary Potter, Henry Martin, and Paul Hindemith serve as points of departure for this study which focuses on four areas: 1) phrasing, 2) step progression, 3) motives and formulas, and 4) harmonic implications. Thematic relationships are discovered through the analysis of the transcription of Lovano's improvisation; the four levels of the analysis work together and also independent of one another to produce a kind of thematic counterpoint. This study also examines how Lovano creates an effective solo. The study will be of benefit to students, professional musicians, pedagogues, theorists, musicologists, and jazz aficionados.

Kirke Mechem (b. 1925), American composer, has a musical output which includes a variety of genres, the most prolific being choral music. This document examines selected choral works by Mechem that are set to the poetry of Sara Teasdale (b. 1884, d. 1933). Included are biographical sketches of Mechem and Teasdale. Selected choral works examined include Christmas Carol (1969) SATB and guitar, The Winds of May, five movement choral cycle (1965) SATB, Birds at Dusk, from the choral cycle Winging Wildly (1998) SATB, and Barter (1995) SA, trumpet, piano 4-hands. Analysis of the poetry involved as well as musical attributes and compositional techniques, including meter, form, harmonic structures, wordpainting, rhythmic treatment and melodic characteristics are included in the discussion.

An accurate fire model is a useful tool in predicting the behavior of a prescribed fire. Simulation of fire requires an extensive amount of data and can be accomplished best using GIS applications. This paper demonstrates integrative procedures of using of ArcGIS™, ERDAS Imagine™, GPS, and FARSITE© to predict prescribed fire behavior on the Kaibab-Paiute Reservation. ArcGIS was used to create a database incorporating all variables into a common spatial reference system and format for the FARSITE model. ArcGIS Spatial Analyst was then used to select optimal burn sites for simulation. Our predictions will be implemented in future interagency efforts towards vegetative restoration on the reservation.

When we looked at different issues in terrorism such as definitions, descriptions and motivations, groups and supporters, tactics, strategies, and victims of terrorists and terrorist activities, we see that terrorism is an issue that can occur at any time, and in any place, and it seems that the terrorism threat will still exist in the future. It is almost impossible to stop all terrorist activities all over the world, but it is possible to formulate an anti-terrorism policy that can keep terrorist activities at a minimum level and prevent planned terror activities by a well developed intelligence network. It seems that to establish a good intelligence collection system an approach in which HUMINT and TECHINT are interdependent with each other is necessary. By using a combination of human and technical intelligence collection methods, intelligence agencies can become more effective and efficient against terrorism.

The study utilized the covariance structure comparison methodology - Multigroup Analysis in Structural Equation Modeling - evaluating measurement equivalence of English and Spanish versions of an employee opinion survey. The concept of measurement equivalence was defined as consisting of four components: sample equivalence, semantic equivalence, conceptual equivalence and scalar equivalence. The results revealed that the two language versions of the survey exhibited acceptable measurement equivalence across five survey dimensions Communications, Supervision, Leadership, Job Content & Satisfaction and Company Image & Commitment. Contrary to the study second hypothesis, there was no meaningful difference in opinion scores between English-speaking and Spanish-speaking respondents on the latent construct of Job Content & Satisfaction.

Over the past twenty years the number of children identified with learning disabilities has risen drastically. In addition, 26 - 40% of these children also experience depression. While cognitive functioning has been demonstrated to be associated with depression, it is unclear whether the mood, vegetative, or cognitive symptoms of depression predict particular cognitive processes and vice versa. The purpose of this study was to determine which particular cognitive processes were associated with specific depressive symptoms and depression as a whole. Structural equation modeling (SEM) was conducted to test a model which examined how three cognitive processing factors (verbal & visual reasoning, and attention/working memory) were associated with three depressive symptom factors (disturbances in mood, vegetative, and cognitive functioning). The data for SEM came from a large data set of children with learning disabilities (n=227). Model fit results supported the proposed model, and a significant association was found between the attention/working memory factor and the depression symptom factor reflecting disturbances in cognitive functioning. Less robust relationships were observed between verbal reasoning and cognitive depressive symptoms and an approach toward the conventional level of significance was noted between visual reasoning and cognitive depressive symptoms. Using a sub-sample of original participants who were …

The purpose of this study was to determine (a) the attentional focus strategies used by triathletes during the three stages of an Olympic distance triathlon, (b) if level of experience influences the attentional focus strategies used by triathletes, and (c) whether there is a relationship between athletes finishing times and the attentional strategies used in each stage of the race. Triathletes (N = 160) completed the Triathlon Attentional Focus Inventory, which measured association and dissociation during the swim, bike, and run. One-way ANOVAs revealed significant differences between the athletes' level of experience and the attentional strategies used, as well as differences between the athletes overall race time and the attentional strategies used during each stage of the triathlon. Athletes with more experience associated more during the race, whereas athletes with less experience dissociated more throughout the race.

The influence of autonomic activation in response to controllable versus noncontrollable stress, anger imagery induction, and relaxation imagery was studied among 80 participants between the ages of 18 and 34. Participants differed in level of trait hostility as assessed by the Irritability Subscale of The Buss-Durkee Hostility Inventory (Buss & Durkee,1957) and the Ho scale of the Cook-Medley Hostility Inventory (Cook & Medley, 1954). Groups were further subdivided with regards to either having a positive family history of cardiovascular disease or having no significant history. Results were obtained through analyses of electrocardiograph R-R intervals which produced an index of autonomic nervous system activation. Findings supported hypotheses involving the relations between autonomic balance and stress and hostility for the female and male populations. Among both populations, parasympathetic regulation was diminished during anger induction for individuals with high levels of trait hostility and having a family history of cardiovascular disease. Similar results were obtained for men during relaxation imagery induction.

A mobile ad hoc network (MANET) is a collection of mobile platforms or nodes that come together to form a network capable of communicating with each other, without the help of a central controller. To avail the maximum potential of a MANET, it is of great importance to devise a routing scheme, which will optimize upon the performance of a MANET, given the high rate of random mobility of the nodes. In a MANET individual nodes perform the routing functions like route discovery, route maintenance and delivery of packets from one node to the other. Existing routing protocols flood the network with broadcasts of route discovery messages, while attempting to establish a route. This characteristic is instrumental in deteriorating the performance of a MANET, as resource overhead triggered by broadcasts is directly proportional to the size of the network. Bounded-dynamic source routing (B-DSR), is proposed to curb this multitude of superfluous broadcasts, thus enabling to reserve valuable resources like bandwidth and battery power. B-DSR establishes a bounded region in the network, only within which, transmissions of route discovery messages are processed and validated for establishing a route. All route discovery messages reaching outside of this bounded region are dropped, thus …

With globalization and modernization, increasingly people are influenced by multiple cultures. This paper examines the case of two authors, Mark Tully and Ruskin Bond, who were born in India shortly before India's Independence (1947). Both had British parents, but one considers himself Indian while the other has retained his British identity. The focus of this paper is how and why this difference has occurred and how it has influenced their writing. Both Tully and Bond write short stories about India and Indians, particularly the small towns and villages. Their reasons for writing, however, are very different. Tully writes to achieve social change, while Bond writes because he loves to write.