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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Clonotypic analysis of CMV-specific CD4+ T cells in human and nonhuman primates

Bitmansour, Arlene Diana. January 2005 (has links) (PDF)
Thesis (Ph. D.) -- University of Texas Southwestern Medical Center at Dallas, 2005. / Vita. Bibliography: 152-170.
232

The effect of the middle school band experience on participation in high school band /

McMahon, Jeremy, January 1900 (has links)
Thesis (M.M.)--Missouri State University, 2008. / "August 2008." Includes bibliographical references (leaves 43-45). Also available online.
233

A study of first-year students within The Ohio State University and the factors influencing nonparticipation in band programs at the collegiate level

Stewart, Michael John, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 112-114).
234

Infrared magneto-spectroscopy of relativistic-like electrons in three-dimensional solids / Etudes magnéto-optiques de matériaux lamellaires avec des bandes électroniques non conventionnelles

Hakl, Michael 07 December 2017 (has links)
L'utilisation de l'équation de Dirac/Weyl conduit à une simplification conceptuelle dans une description de la structure de la bande dans les solides à faible échelle d'énergie. En particulier, les excitations d'électrons-trous peuvent être considérées comme analogues au cas relativiste tel que conductivité optique linéaire, le suppression de backscattering ou la manifestation des arcs de Fermi et la chiralité des particules. En outre, la phase semi-métallique est également un élément crucial pour la classification des matériaux. La taille de le gap est affectée qualitativement par le type de dispersion d'énergie par un croisement continu des bandes linéaires à paraboliques. Cela peut être compris comme une limite classique ou ultra-relativiste du mouvement d'une particule massive.La spectroscopie infrarouge de la transformation de Fourier est une technique unique pour étudier les excitations optiques dans une large gamme d'énergies et représente en combinaison avec le champ magnétique élevé un outil puissant pour sondage de la structure électronique et surmonte le principal obstacle des systèmes sans gap qui est un dopage fort en raison de désordre structurel.La première partie du travail est consacrée à l'arséniure de cadmium, où nous élaborons une approche de distinction qualitative entre les systèmes Dirac et Kane qui ont été utilisés pour prouver sur la base de la réponse magnéto-optique observée la réalisation du modèle Kane presque sans gap avec une similitude frappante avec HgCdTe, en contradiction avec l'existence de cônes purement Dirac. La magnéto-réflectivité dans un champ magnétique à champ élevé la résonance cyclotron caractéristiques par un radical-B dépendance avec un comportement particulier dans la limite quantique. En revanche, la magnéto-transmission montrait des transitions de niveau Landau qui doit être interprétées que comme un type plat-à-cône afin de préserver une cohérence totale du modèle. Les cônes de Dirac prédits par la théorie sont susceptibles de coexister dans le modèle de Kane sous la forme d'une sous-structure décrite par le modèle de Bodnar qui se rapproche de la structure cristalline complexe par une simple cellule antifluorite qui permet d'utiliser la théorie du k.p classique.Dans la deuxième partie, nous nous concentrons sur le bismuth comme isolant topologique 3D archétype. Nous étudions une condition particulière obéie pour le BHZ-hamiltonien qui apporte des propriétés intriguantes comme une relation inhabituelle de spin gap et la résonance du cyclotron, l'épinglage spécifique entre les fancharts des sous-groupes Landau ou les g-facteurs compensés dans les bandes de conduction et de valence. Les mesures de photoluminescence ont montré une émission directgap, ce qui donne un nouvel aperçu de la structure largement acceptée à partir des données ARPES, où la “chameau structure” de la bande de valence doit être expliquée dans le confinement de surface et le point de Dirac de l'état de surface doit être repositionné par rapport aux bandes en bulk. La réponse magnéto-optique peut être pleinement expliquée dans une image classique du paramagnétisme de Pauli comme un simple effet d'occupation. Un tel comportement se manifeste dans la transmission en tant que fractionnement progressif du bord d'absorption interbande avec une saturation successive due à la polarisation spin partielle ou totale des électrons. Le dichroïsme relatif entraîne également une forte rotation de Faraday linéaire décrite par un modèle simple de la constante Verdet qui ne dépend pas sur le niveau de Fermi. / The use of the Dirac/Weyl equation leads to a conceptual simplification in a description of the band structure in solids at low energy scales. In particular, electron-hole excitations can be regarded as an analogue to the relativistic case with several expected phenomena to be observed in the condensed systems such as a suppressed back-scattering, linear optical conductivity or the manifestation of the Fermi arcs and particle's chirality. Moreover, the semimetallic phase also symbolizes a boundary between the trivial and topological insulators and thus play a crucial role for the material classification. The size of the gap qualitatively affects the type of the energy dispersion by a continuous crossover from the linear to parabolic bands. This fact can be easily understood as a classical or ultra-relativistic limit of the motion of a free massive particle.Infrared Fourier transform spectroscopy is a unique technique for studying optical excitations in a wide range of energies and it represents in combination with the high magnetic field a powerful tool for probing electronic structure and overcomes the main obstacle of the gapless systems that is a strong doping due to the structural disorder.The first part of the work is devoted to cadmium arsenide, where we elaborate an approach to qualitatively distinguish between the Dirac and Kane systems that was used to prove on the basis of the observed magneto-optical response the realization of the nearly gapless Kane model with a striking similarity to HgCdTe, contradicting the existence of purely Dirac cones. The magneto-reflectivity revealed a strong splitting of the plasma edge that turns into the cyclotron resonance characteristic by a squareroot-of-B dependence in the high magnetic field with a particular behaviour in the quantum limit independent on the initial Fermi level. In contrast, the magneto-transmission revealed interband Landau level transitions that could be only interpreted as a flat-to-cone type in order to preserve a full consistency of the model. The Dirac cones predicted by theory are feasible to coexist within the Kane model in the form of a substructure described by the Bodnar model that approximates the complex crystal structure by a simple antifluorite cell, which allows to use the conventional k.p-theory.In the second part, we focus on bismuth selenide entitled as an archetypal 3D topological insulator. We study a peculiar condition fulfilled for the BHZ-hamiltonian that brings intriguing properties such as an unusual relation of the spin gap and cyclotron resonance, the specific pinning between fancharts of Landau subsets or the compensated g-factors of the conduction and valence bands. The photoluminescence measurements showed a direct-gap emission, that gives a new insight to the widely accepted structure from ARPES data, where the declared camel-back structure of the valence band needs to be explained within the surface confinement and the Dirac point of the surface state should be repositioned with respect to the bulk bands. The magneto-optical response can be fully explained in a classical picture of the Pauli paramagnetism as a purely occupational effect. Such behaviour is evinced in the transmission as a gradual splitting of the interband absorption edge with a successive saturation due to the partial or total spin polarization of electrons. The related dichroism drives also a strong linear Faraday rotation described by a simple model of the Verdet constant that depends only on the Fermi level.
235

Analyzing The Effects of Bollinger Bands on the Probability of Stock Options Using Support Vector Machines

January 2015 (has links)
abstract: The purpose of this research is to efficiently analyze certain data provided and to see if a useful trend can be observed as a result. This trend can be used to analyze certain probabilities. There are three main pieces of data which are being analyzed in this research: The value for δ of the call and put option, the %B value of the stock, and the amount of time until expiration of the stock option. The %B value is the most important. The purpose of analyzing the data is to see the relationship between the variables and, given certain values, what is the probability the trade makes money. This result will be used in finding the probability certain trades make money over a period of time. Since options are so dependent on probability, this research specifically analyzes stock options rather than stocks themselves. Stock options have value like stocks except options are leveraged. The most common model used to calculate the value of an option is the Black-Scholes Model [1]. There are five main variables the Black-Scholes Model uses to calculate the overall value of an option. These variables are θ, δ, γ, v, and ρ. The variable, θ is the rate of change in price of the option due to time decay, δ is the rate of change of the option’s price due to the stock’s changing value, γ is the rate of change of δ, v represents the rate of change of the value of the option in relation to the stock’s volatility, and ρ represents the rate of change in value of the option in relation to the interest rate [2]. In this research, the %B value of the stock is analyzed along with the time until expiration of the option. All options have the same δ. This is due to the fact that all the options analyzed in this experiment are less than two months from expiration and the value of δ reveals how far in or out of the money an option is. The machine learning technique used to analyze the data and the probability is support vector machines. Support vector machines analyze data that can be classified in one of two or more groups and attempts to find a pattern in the data to develop a model, which reliably classifies similar, future data into the correct group. This is used to analyze the outcome of stock options. / Dissertation/Thesis / Masters Thesis Computer Science 2015
236

The Role of the Clarinet in China

January 2017 (has links)
abstract: Throughout western clarinet art music, there are not only a large number of great performers and classical works, but also a valuable body of literature that has laid a solid foundation for clarinet development and global dispersion. By contrast, Chinese clarinet literature is lacking in quantity and global distribution. However, this is the first comprehensive study that discloses the mysterious mask of China’s clarinet art. This study does not merely discuss the Chinese clarinet history, but it also introduces important historical events that influenced the development of the Chinese clarinet industry (excluding manufacturing), including Chinese military bands, clarinet music, pedagogy, clarinet figures, and its future direction. In the conclusion of this paper, the author discusses the deficiency of the Chinese clarinet industry and makes suggestions for solving problems with clarinet players practicing more technique rather than focusing on musicianship, educators’ lack of concentration on teaching and academic research, and the shortage of Chinese clarinet works. Additionally, the author appeals to Chinese clarinet players to actively participate in international activities and the Chinese government to increase incentives to introduce high-level Chinese talents overseas to help make China a better country in any field. / Dissertation/Thesis / Theme and Variations_Shuang Zhu / The Song of Grazing Horses_Shuang Zhu / The Sound of Pamir I_Shuang Zhu / The Sound of Pamir II_Shuang Zhu / The Sound of Pamir III_Shuang Zhu / Doctoral Dissertation Music 2017
237

Etude expérimentale sur la localisation des déformations dans les grès poreux / Experimental Study of localised deformation in porous sandstones

Charalampidou, Elli Maria 03 May 2011 (has links)
Cette étude expérimentale traite la localisation des déformations sur un grès poreux: le grès de Vosges. Un nombre des essais triaxiaux sont effectués sous des pressions de confinement (i.e., 20 MPa - 190 MPa) et des déformations axiales différentes pour mieux comprendre la réponse mécanique de ce grès. La localisation des déformations a été étudiée dans des différentes échelles en appliquant une variation de mesures de champs (full-field methods) comme la Tomographie Ultrasonore (en 2D), les Emissions Acoustiques (en 3D), les Rayons X (en 3D), et la Corrélation des Images (en 3D). Les méthodes expérimentales ont été appliquées avant, pendant et après les essais triaxiaux. Des coupes fine ont été observées sous le microscope optique et électronique (SEM). La combinaison des multiples techniques expérimentales, qui ont des différentes sensitivités et résolutions, a décrit la procédure de la formation et l’évolution des bands de déformation observées sur le grès de Vosges. Des bandes de cisaillement ont été formées sous des pressions intermédiaires et des bandes de compaction sous des pressions élevées. Des bandes de compactions pure n’ont pas été observées.Les bandes de déformations observées se sont caractérisées comme des zones de déformation de cisaillement localisée et/ou de compaction. En plus, elles se sont caractérisées comme des structures de fable vitesse ultrasonore, des places d’origine des fissures inter- ou intra- granulaires, et des places des densités de matériel élevées.Deux mécanismes principales ont été observées au niveau de grain dans les bandes de cisaillement et de bandes de compaction (shear-enhanced compaction bands): d’un cote c’est la fissuration des grains (endommagement) et de l’autre cote c’est la réduction de porosité (sur la forme de compaction). Les deux mécanismes i présent différences sur leurs proportions et leur ordre d’occurrence dans le temps. / This PhD thesis presents a laboratory study aiming at a better understanding of the stress-strain response of the Vosges sandstone (porous rock) tested at a range of confining pressures (i.e., 20-190 MPa) and different axial strain levels. Localised deformation was captured at different scales by a combination of full-field experimental methods, including Ultrasonic Tomography (2D), Acoustic Emissions (3D), X-ray Tomography (3D), and 3D volumetric Digital Image Correlation, plus thin section and Scanning Electron Microscope observations (2D). These experimental methods were performed before, during and after a number of triaxial compression tests. The combined use of the experimental techniques, which have different sensitivity and resolution, described the processes of shear band and shear-enhanced compaction band generation, which formed at low to intermediate and relatively high confining pressures, respectively. Pure compaction bands were not identified. The deformation bands were characterised as zones of localised shear and/or volumetric strain and were captured by the experimental methods as features of low ultrasonic velocities, places of inter- and intra-granular cracking and structures of higher density material. The two main grain-scale mechanisms: grain breakage (damage) and porosity reduction (compaction) were identified in both shear band and shear-enhanced compaction band formation, which presented differences in the proportions of the mechanism and their order of occurrence in time.
238

Concepções e ações de educação musical no projeto de bandar e fanfarras de São José-SC: três estudos de caso / Concepts and action on musical education in the bands and fanfarres projetcs of São José-SC: three cases studies

Cislaghi, Mauro César 14 March 2009 (has links)
Made available in DSpace on 2016-12-08T17:06:49Z (GMT). No. of bitstreams: 1 CISLAGHIMauro Cesar.pdf: 548990 bytes, checksum: c6d1fcccecc309d53a001acceec35cee (MD5) Previous issue date: 2009-03-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The purpose of this paper is to report and analyze the concepts of the teachers about musical education and the teaching and learning processes applied at the Projeto de Bandas e Fanfarras de São José SC. A bibliography about musical education in musical bands was used and the theoretical reference adopted can be found in the pedagogical trends synthesized by Libâneo (1994). Three qualitative case studies were performed, and the research techniques used were observation, semi-structured interviews and questionnaires. From the analysis, one might observe that a few concepts of teachers on musical education are effectively the pedagogical practices. The musical teaching and learning processes vary according to each teacher s approach, who can use many different pedagogies even though they are not aware of the theories. The results also show the importance of the Bands and Fanfares Project in the life of participating children and young adults, providing a more complete formation as citizens. Furthermore, the possible contributions of this research to musical education are also presented on it / O presente trabalho teve como objetivo registrar e analisar as concepções dos professores sobre educação musical e os processos de ensino e aprendizagem de música realizados no Projeto de Bandas e Fanfarras de São José - SC. Foi utilizada uma bibliografia que aborda a educação musical em bandas de música, e o referencial teórico adotado encontra-se nas tendências pedagógicas sintetizadas por Libâneo (1994). Foi realizado três estudos de caso, com abordagem qualitativa, sendo utilizados como técnicas de pesquisa a observação, entrevista semi-estruturada e questionários. A partir da análise, observa-se que algumas das concepções dos professores sobre educação musical se configuram efetivamente nas práticas pedagógicas. Os processos de ensino e aprendizagem de música variam conforme a abordagem realizada por cada professor, os quais utilizam traços de diversas pedagogias mesmo desconhecendo suas teorias. Os resultados sinalizam também para a importância do Projeto de Bandas e Fanfarras na vida das crianças e jovens participantes, proporcionando uma formação mais ampla como cidadãos. Além disso, são apresentadas as possíveis contribuições desta pesquisa para a área de educação musical
239

Dinâmica de Partículas em Estruturas Periódicas

Vieira, Marcelo da Silva 22 December 2010 (has links)
Made available in DSpace on 2015-05-14T12:14:03Z (GMT). No. of bitstreams: 1 arquivocompleto.pdf: 1077441 bytes, checksum: 7e40786e3a70b55afbfcd9bdc28c5ffa (MD5) Previous issue date: 2010-12-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / One of the foundations of the actual technology is the Quantum Mechanics. Through Quantum Mechanics, with the development of semiconductors physics, we are able to build devices which, manipulate particles for certain purposes. As an example of these devices, we have the diode and transistor. In this thesis we seek physical systems, to obtain some quantum effects, theorically. The quantum effects which we want to obtain, are a band structure for photons and charged particles, the Aharonov-Bohm effect for photons and geometric phases for relativistic particles described by non-Hermitian Hamiltonian. For this purpose, the issues addressed here are: the study of photons in photonic crystals formed by topological insulators, the description of systems of charged particles of varying mass, the study of dynamics of the charged particles with periodic mass, the study of the Aharonov- Bohm for the photon through a viscous uid, and the appearance of geometric phases for relativistic particles described by non hermitian Hamiltonian. The main contributions of our work was the proposal for a Hamiltonian which describes particles with variable mass, obtaining a structure of energy bands for a charged particle with periodic mass, obtaining a structure of frequency bands for photons in a photonic crystal formed by topological insulators , showing the Aharonov-Bohm effect for the photon, where the vorticity of a viscous uid is the role of magnetic fields confined, and show that relativistic particles subject to non-Hermitian Hamiltonian which varies slowly, has complex geometric phases. / A tecnologia que usamos nos dias de hoje tem como uma de suas bases principais, a Mecânica Quântica. Através da Mecânica Quântica, com o desenvolvimento da física dos semicontutores, somos capazes de construir dispositivos os quais, manipulam partículas para determinados fins. Como exemplo destes dispositivos, temos o diodo e o transistor, que são o coração da eletrônica. Nesta tese, buscamos teoricamente sistemas físicos para a obtenção de certos efeitos quânticos. Tais efeitos que desejamos obter são, uma estrutura de bandas para fótons e partículas carregadas, o efeito Aharonov-Bohm para fótons, e fases geométricas para partículas relativísticas descritas por hamiltonianos não hermitianos. Para tal finalidade, os problemas tratados aquisição: o estudo de fótons em cristais fotônicos formados por isolantes topológicos, a descrição de sistemas de partículas carregadas de massa variável, o estudo da dinâmica de partículas carregadas de massa periódica, o estudo do efeito Aharonov-Bohm para o fóton através de um fluido viscoso, e o surgimento de fases geométricas para partículas relativísiticas sujeitas a hamiltonianos não hermitianos e que variam lentamente. As principais contribuições do nosso trabalho, foram a proposta para um hamiltoniano que descreve partículas com massa variável, a obtenção de uma estrutura de bandas de energia para uma partícula carregada com massa periódicas, a obtenção de uma estrutura de bandas de frequência para fótons num cristal fotônico formado por isolantes topológicos, á obtenção de um análogo do efeito Aharonov-Bohm para o fóton, onde a vorticidade de um uido viscoso faz o papel do campo magnético confinado, e mostrar que partículas relativísticas sujeitas a hamiltonianos não hermitianos e que variam lentamentem, apresentam fases geométricas complexas.
240

Approche non locale en plasticité cristalline : application à l'étude du comportement mécanique de l'acier AISI 316LN en fatigue oligocyclique / Non local approach in cristalline plasticity : study of mechanical behaviour of AISI 316LN stainless steel during low cycle fatigue

Schwartz, Julien 15 June 2011 (has links)
Si l'amorçage des fissures de fatigue est aujourd'hui bien compris dans le cas de monocristaux de métaux purs, ce phénomène s'avère plus complexe à cerner et à prédire dans le cas d'alliages métalliques polycristallins tels que l'acier AISI 316LN.D'un point de vue expérimental, notre étude s'est concentrée sur la caractérisation du comportement mécanique et l'étude, à différentes échelles, des phénomènes liés à l'amorçage des fissures de fatigue oligocyclique dans l'acier 316LN. Pour des niveaux de déformation appliquée de Δε/2 = 0,3 et 0,5%, l'adoucissement cyclique observé au cours des essais coïncide avec l'organisation des dislocations sous forme de bandes. Ces bandes sont liées à l'activation des systèmes de plus haut facteur de Schmid. Elles portent la majeure partie de la déformation et provoquent en surface des intrusions et extrusions favorisant l'apparition et la coalescence de fissures.D'un point de vue modélisation, nous avons proposé un nouveau modèle de plasticité cristalline intégrant des dislocations géométriquement nécessaires (GND) directement calculées à partir du second gradient de la rotation élastique. Implémenté dans les codes d'éléments finis AbaqusTM et Cast3mTM, ce modèle s'inspire des travaux sur le monocristal en transformations finies de Peirce et al. (1983) et de Teodosiu et al. (1993). Adapté au cas des polycristaux par Hoc (1999) et Erieau (2003), il a été enrichi par l’introduction GND selon la théorie proposée par Acharya et Bassani (2000). Les simulations réalisées sur des différents types d'agrégats (2D extrudé et 3D) montrent que la prise en compte de GND permet :- de reproduire les effets de taille de grains au niveau macroscopique et local,- de décrire plus finement les champs de contraintes calculés.Ces simulations ont permis de mettre en évidence l'influence des matrices d'élasticité et d'écrouissage sur les valeurs et l'évolution des contraintes macroscopique effective et cinématique moyenne et le rôle important des conditions aux limites lors des calculs d'agrégats. / If fatigue crack initiation is currently quite well understood for pure single crystals, its comprehension and prediction in cases of polycrystal alloys such as AISI 316LN stainless steel remain complicated.Experimentally our study focuses on the characterisation of the mechanical behaviour and on the study at different scales of the phenomenon leading to low cycle fatigue crack initiation in 316LN stainless steel. For straining amplitudes of Δε/2 = 0,3 and 0,5%, the cyclic softening observed during testing has been related to the organisation of dislocations in band structures. These bands, formed due to the activation of slip systems having the greatest Schmid's factor, carry the most part of the deformation. Their emergence at free surfaces leads to the formation of intrusions and extrusions which help cracks initiate and spread.Numerically we worked on the mesoscopic scale, proposing a new model of crystalline plasticity. This model integrates geometrically necessary dislocations (GND) directly computed from the lattice curvature. Implemented in the finite element code AbaqusTM and Cast3mTM, it is based on single crystal finite deformations laws proposed by Peirce et al. (1983) and Teodosiu et al. (1993). Extended for polycrystals by Hoc (2001) and Erieau (2003), it has been improved by the introduction of GND (Acharya and Bassani, 2000). The simulations performed on different types of aggregates (2D/3D) have shown that taking GND into account enables:- the prediction of the grain size effect on a macroscopic and on a local scale,- a finer computation of local stress field.The influence of the elasticity and interaction matrices on the values and the evolution of the isotropic and kinematic mean stresses has been shown. The importance of boundary conditions on computed mechanical fields could also be pointed out.

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