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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.
21

Linear Algebra on the Lie Algebra on Two Generators

Webb, Sarah 21 December 2022 (has links)
No description available.
22

Analysis of Strain, Shape, and Orientation of the Deformed Pebbles in the Seine River Area, Ontario

Hsu, Mao-Yang 02 1900 (has links)
<p> Detailed mapping was carried out to provide reliable data concerning the geologic structure which is relevant to the original pebble fabrics. </p> <p> Mathematical determination of an ellipsoidal shape from any two cross-sections and its application to the study of deformed ellipsoidal particles are developed and discussed. </p> <p> Final pebble fabric resulting from special coaxial superpositions of the tectonic strain ellipsoid upon originally ellipsoidal pebbles, is employed to determine the strain ratio and the original pebble orientation and shape. </p> <p> Some general techniques are outlined for different cases to determine the strain ellipsoid and the original shape of deformed pebbles. Weighted vector mean is introduced in the orientation analysis of deformed pebbles. The concept of average axial ratio in the case of unextractable pebbles is examined. </p> <p> Pebble size, pebble ductility ratio, shortening strain, and strain rate are all calculated and discussed. Finally, selective veins developing in the less-deformed pebbles are subjected to detailed orientation and petrofabric analyses. </p> / Thesis / Doctor of Philosophy (PhD)
23

Strain and Grain Size Analysis of a Deformed Archean Pyroclastic Flow, Temagami, Ontario

Frost, David Harold 04 1900 (has links)
<p> The Archean pyroclastic conglomerate studied has six clast types which can be condensed to four clast families based on lithology. The quartz clasts have an average strain of X:Y:Z=1.21:1:0.55 while the pumice clasts have an average strain of X:Y:Z=1.27:1:0.47. The difference is strain between these clast families can be attributed to their different viscosities. The quartz clasts have an assumed viscosity ratio between the clasts and the matrix of unity and are taken to represent the strain in the rock as a whole. The sulphide and black clasts have strain ratios much higher than the quartz because of recrystallization of the sulphide and cleavage formation effecting the black clasts.</p> <p> The sedimentary structure of the deposit and its position between mafic pillow basalts indicate that the deposit is a result of the deposition of a subaqueous pyroclastic debris flow in a proximal environment.</p> / Thesis / Bachelor of Science (BSc)
24

Topics In Noncommutative Gauge Theories And Deformed Relativistic Theories

Chandra, Nitin 07 1900 (has links) (PDF)
There is a growing consensus among physicists that the classical notion of spacetime has to be drastically revised in order to nd a consistent formulation of quantum mechanics and gravity. One such nontrivial attempt comprises of replacing functions of continuous spacetime coordinates with functions over noncommutative algebra. Dynamics on such noncommutative spacetimes (noncommutative theories) are of great interest for a variety of reasons among the physicists. Additionally arguments combining quantum uncertain-ties with classical gravity provide an alternative motivation for their study, and it is hoped that these theories can provide a self-consistent deformation of ordinary quantum field theories at small distances, yielding non-locality, or create a framework for finite truncation of quantum field theories while preserving symmetries. In this thesis we study the gauge theories on noncommutative Moyal space. We nd new static solitons and instantons in terms of the so-called generalized Bose operators (GBO). GBOs are constructed to describe reducible representation of the oscillator algebra. They create/annihilate k-quanta, k being a positive integer. We start with giving an alternative description to the already found static magnetic flux tube solutions of the noncommutative gauge theories in terms of GBOs. The Nielsen-Olesen vortex solutions found in terms of these operators also reduce to the ones known in the literature. On the other hand, we nd a class of new instanton solutions which are unitarily inequivalent to the ones found from ADHM construction on noncommutative space. The charge of the instanton has a description in terms of the index representing the reducibility of the Fock space representation, i.e., k. After studying the static soliton solutions in noncommutative Minkowski space and the instanton solutions in noncommutative Euclidean space we go on to study the implications of the time-space noncommutativity in Minkowski space. To understand it properly we study the time-dependent transitions of a forced harmonic oscillator in noncommutative 1+1 dimensional spacetime. We also provide an interpretation of our results in the context of non-linear quantum optics. We then shift to the so-called DSR theories which are related to a different kind of noncommutative ( -Minkowski) space. DSR (Doubly/Deformed Special Relativity) aims to search for an alternate relativistic theory which keeps a length/energy scale (the Planck scale) and a velocity scale (the speed of light scale) invariant. We study thermodynamics of an ideal gas in such a scenario. In first chapter we introduce the subjects of the noncommutative quantum theories and the DSR. Chapter 2 starts with describing the GBOs. They correspond to reducible representations of the harmonic oscillator algebra. We demonstrate their relevance in the construction of topologically non-trivial solutions in noncommutative gauge theories, focusing our attention to flux tubes, vortices, and instantons. Our method provides a simple new relation between the topological charge and the number of times the basic irreducible representation occurs in the reducible representation underlying the GBO. When used in conjunction with the noncommutative ADHM construction, we nd that these new instantons are in general not unitarily equivalent to the ones currently known in literature. Chapter 3 studies the time dependent transitions of quantum forced harmonic oscillator (QFHO) in noncommutative R1;1 perturbatively to linear order in the noncommutativity . We show that the Poisson distribution gets modified, and that the vacuum state evolves into a \squeezed" state rather than a coherent state. The time evolutions of un-certainties in position and momentum in vacuum are also studied and imply interesting consequences for modelling nonlinear phenomena in quantum optics. In chapter 4 we study thermodynamics of an ideal gas in Doubly Special Relativity. We obtain a series solution for the partition function and derive thermodynamic quantities. We observe that DSR thermodynamics is non-perturbative in the SR and massless limits. A stiffer equation of state is found. We conclude our results in the last chapter.
25

Cálculo de potenciais deformados no contexto do modelo generalizado de rotação-vibração / Calculation of deformed potentials in the context of the generalized rotation-vibration model

Botero, Daniel Felipe Morales 14 October 2013 (has links)
Para efeito de aplicação em cálculos de canais acoplados, potenciais calculados de maneira exata para sistemas envolvendo núcleos deformados não são adequados, pois resultariam em integrais multidimensionais muito difíceis de serem calculadas numericamente pelo tempo de cálculo computacional que isso implica. Nesta dissertação, apresentamos expressões para calcular de maneira aproximada os potenciais nuclear e coulombiano entre núcleos deformados, sendo essas expressões uma generalização de resultados obtidos em trabalhos anteriores. Os cálculos foram feitos no contexto do Modelo Generalizado de Rotação-Vibração (GRVM), que é um modelo de estrutura nuclear desenvolvido recentemente. Para obter essas expressões, as densidades nucleares foram expandidas até segunda ordem na deformação e foi levado em conta um valor finito para a difusividade nuclear nos cálculos de dupla convolução. Comparamos os correspondentes resultados obtidos com aqueles provenientes de algumas outras expressões, usualmente assumidas nesse tipo de cálculos, e também com os valores exatos (obtidos ao resolver numericamente a integral sextupla no cálculo de dupla convolução). As análises mostraram que a nossa aproximação -GRVM- é superior a essas outras de uma maneira geral, e, em particular, de forma muito melhor na região de pequenas distâncias de interação. As expressões analíticas do GRVM exprimem a dependência do potencial com as deformações de maneira explícita, sendo essa característica extremamente útil para a obtenção de potenciais de acoplamento de maneira analítica / For systems involving deformed nuclei, potentials calculated through an exact form are not appropriated for applications in coupled-channel (CC) calculations, because they result in multidimensional integrals impossible to be calculated numerically. In this work, we present equations for calculating the heavy-ion nuclear and Coulomb potentials, in an approximate form, that express the dependence of the potential on the deformations explicitly. This characteristic is extremely useful for obtaining coupling potentials analytically. The calculations were made in the context of the Generalized Rotation-Vibration Model (GRVM), which is a recently developed model of nuclear structure. To obtain these expressions, the nuclear densities were expanded up to second order in the deformation and a finite diffuseness value was taken into account in the calculation of the double-folding potential. We have compared the corresponding results with those obtained from other expressions usually assumed in such calculations, and also with the exact potential strength values (obtained by solving numerically the six dimensional integral of the double-folding calculation). The analyses show that our approach presents better results than the others, particularly so much better in the region of interaction of small distances.
26

CENTRIFUGE MODELLING STUDY OF CONTRASTING STRUCTURAL STYLES IN THE SALT RANGE AND THE POTWAR PLATEAU, PAKISTAN

FAISAL, SHAH 07 August 2010 (has links)
The ENE-trending Himalayan fold-thrust belt in Pakistan exhibits contrasting deformation styles both along and across the strike. The centrifuge modelling technique has been used to investigate these variations in structural style. For the purpose of modelling, the Salt Range and Potwar Plateau (SR/PP) stratigraphy has been grouped into four mechanical units. From bottom to top these are the Salt Range Formation, carapace unit (Cambrian-Eocene platform sequences), Rawalpindi Group, and Siwalik Group. These stratigraphic units of alternating competence, composed of thin layers of plasticine modelling clay and silicone putty, rest on a rigid base plate that represents the crystalline basement of the Indian plate. The models are built at a linear scale ratio of ~10-6 (1mm=1km) and deformed in a centrifuge at 4000g. The models are subjected to horizontal shortening by collapse and lateral spreading of a “hinterland wedge” which simulates overriding by the Himalayan orogen (above the Main Boundary Thrust). The models of the central SR/PP show that the accretionary wedge develops a prominent culmination structure with fault-bend fold geometry over the frontal ramp, while the eastern SR/PP is more internally deformed by detachment folds, fault-propagation folds and pop-up and pop-down structures. Model results show that the transition from fault-bend fold to detachment-fold and fault-propagation-fold geometry in the prototype may take place in a transfer zone marked by an S-bend structure (Chambal Ridge and Jogi Tilla) at the surface and the lateral ramp in the subsurface. Moreover, the models suggest that an oblique ramp below the Kalabagh strike-slip connecting the two frontal ramps below the Surghar Range and the central Salt Range developed similar structure that can be observed in the prototype. The model results also show that the Northern Potwar Deformed Zone may have been developed over ductile substrata due to the close similarity between the models and the prototype structures. The deformation style in the models illustrates the importance of mechanical stratigraphic and basement ramp systems in the evolution and the structural styles of the SR/PP. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2010-07-29 19:42:25.027
27

Espectro do operador Laplaciano de Dirichlet em tubos deformados

Mamani, Carlos Ronal Mamani 21 March 2014 (has links)
Made available in DSpace on 2016-06-02T20:28:29Z (GMT). No. of bitstreams: 1 5894.pdf: 474601 bytes, checksum: 5d3ab33b83cca94abae2ce5efc49bf32 (MD5) Previous issue date: 2014-03-21 / Financiadora de Estudos e Projetos / Let &#8486; be a deformed tube in(continue...) / Seja um tubo deformado em (continua)
28

Cálculo de potenciais deformados no contexto do modelo generalizado de rotação-vibração / Calculation of deformed potentials in the context of the generalized rotation-vibration model

Daniel Felipe Morales Botero 14 October 2013 (has links)
Para efeito de aplicação em cálculos de canais acoplados, potenciais calculados de maneira exata para sistemas envolvendo núcleos deformados não são adequados, pois resultariam em integrais multidimensionais muito difíceis de serem calculadas numericamente pelo tempo de cálculo computacional que isso implica. Nesta dissertação, apresentamos expressões para calcular de maneira aproximada os potenciais nuclear e coulombiano entre núcleos deformados, sendo essas expressões uma generalização de resultados obtidos em trabalhos anteriores. Os cálculos foram feitos no contexto do Modelo Generalizado de Rotação-Vibração (GRVM), que é um modelo de estrutura nuclear desenvolvido recentemente. Para obter essas expressões, as densidades nucleares foram expandidas até segunda ordem na deformação e foi levado em conta um valor finito para a difusividade nuclear nos cálculos de dupla convolução. Comparamos os correspondentes resultados obtidos com aqueles provenientes de algumas outras expressões, usualmente assumidas nesse tipo de cálculos, e também com os valores exatos (obtidos ao resolver numericamente a integral sextupla no cálculo de dupla convolução). As análises mostraram que a nossa aproximação -GRVM- é superior a essas outras de uma maneira geral, e, em particular, de forma muito melhor na região de pequenas distâncias de interação. As expressões analíticas do GRVM exprimem a dependência do potencial com as deformações de maneira explícita, sendo essa característica extremamente útil para a obtenção de potenciais de acoplamento de maneira analítica / For systems involving deformed nuclei, potentials calculated through an exact form are not appropriated for applications in coupled-channel (CC) calculations, because they result in multidimensional integrals impossible to be calculated numerically. In this work, we present equations for calculating the heavy-ion nuclear and Coulomb potentials, in an approximate form, that express the dependence of the potential on the deformations explicitly. This characteristic is extremely useful for obtaining coupling potentials analytically. The calculations were made in the context of the Generalized Rotation-Vibration Model (GRVM), which is a recently developed model of nuclear structure. To obtain these expressions, the nuclear densities were expanded up to second order in the deformation and a finite diffuseness value was taken into account in the calculation of the double-folding potential. We have compared the corresponding results with those obtained from other expressions usually assumed in such calculations, and also with the exact potential strength values (obtained by solving numerically the six dimensional integral of the double-folding calculation). The analyses show that our approach presents better results than the others, particularly so much better in the region of interaction of small distances.
29

Byron's Shakespearean Imitations

Barber, Benjamin January 2016 (has links)
Though Byron is known for his provocative denials of the importance of Shakespeare, his public derogations of the early modern playwright are in fact a pose that hides the respect he had for the playwright’s powerful poetic vision, a regard which is recorded most comprehensively in the Shakespearean references of Don Juan. Byron imitated Shakespeare by repeating and adapting the older poet’s observations on the imitative nature of desire and the structure of emulous ambition as a source of violence. His appropriations make his work part of the modern shift away from earlier European societies, wherein ritual means of mitigating desire’s potentially inimical impact on human communities were supplemented with an increased reliance on market mechanisms to defer the effects of emulation and resentment. Finding himself among the first modern celebrities, Byron deploys Shakespeare’s representations of desire to trace the processes that produced the arc of his own fame and notoriety. Drawing on his deep knowledge of Shakespeare, Byron’s poetic vision—in its observations on the contagious nature of desire—exhibits elements of Shakespeare’s own vivid depictions of imitation as a key conduit for his characters’ cupidity, ambitions, and violence. Exploring how he plays with and integrates these representations into his letters, journals, poetry, and plays, my dissertation investigates Byron’s intuitions on the nature of human desire by focusing on his engagement with one of literature’s greatest observers of human behaviour, Shakespeare.
30

Couplages multi-physiques : évaluation des impacts méthodologiques lors de simulations de couplages neutronique/thermique/mécanique. / Multi-physics couplings : methodology impact evaluation for neutron transport /heat transfer /mechanics coupling simulations.

Patricot, Cyril 22 March 2016 (has links)
L’objectif de cette thèse est l’étude des méthodes de couplage entre neutronique, thermique et mécanique. Après une revue générale des techniques de couplage, on s’est intéressé à la prise en compte de déformations mécaniques dans les simulations neutroniques. Les codes actuels de neutronique utilisant des méthodes déterministes ne sont généralement pas capables de traiter une géométrie déformée. Ce type de calcul a pourtant un intérêt fort pour la filière rapide et est un prérequis indispensable pour l’étude du couplage envisagée.Deux approches ont été identifiées et implémentées pour répondre à cette problématique, selon que l’on utilise un maillage de calcul mobile ou fixe. Elles ont été testées et confrontées sur les essais de gerbage du réacteur Phénix. Le couplage a été étudié ensuite, avec l’approche à maillage mobile, sur l’expérience Godiva qui présente un couplage à la fois conceptuellement simple et fort entre les physiques qui nous intéressent. Ces travaux ont permis de mettre en avant l’utilisation de la méthode de factorisation quasi-statique en neutronique qui permet de coupler efficacement un solveur de neutronique cinétique avec une autre discipline. Travail plus amont, le développement d’un solveur directement multiphysique a également été exploré. L’utilisation de l’algorithme de Newton sur les formes discrétisées des équations couplées a donné de bons résultats et semble être une approche généralisable à d’autres couplages.Cette thèse débouche ainsi à la fois sur une meilleure compréhension de la physique des cœurs déformés et sur des outils opérationnels pour leur simulation, mais aussi sur des recommandations très générales pour la mise en œuvre de calculs couplés. / The objective of this thesis is to study coupling techniques between neutron transport, heat transfer and mechanics. First, a very general review of coupling techniques in the literature was done. Then we worked on neutron transport simulations in wrapped cores. Most of current deterministic codes for neutron transport are not able to deal with deformed geometry. This kind of computations is however of special interest for fast neutrons reactors and is a prerequisite for our planned coupling study.Two approaches were identified and implemented to take into account core deformations, using respectively mobile and fixed meshing. They were tested and compared on the flowering tests of the reactor Phenix. The coupling itself was studied afterwards, on the Godiva experiment. It was chosen because of the direct, strong and time-dependent coupling it involves. On this case, the “quasi-static” factorization of neutron flux was shown to be an effective way to couple a space- and time-dependent neutron transport solver with another discipline. We also investigated the development of a unique multiphysics solver. The well-known Newton algorithm applied to the discretized forms of the coupled equations was shown to be an efficient tool, which could be generalized to other couplings.This thesis therefore leads, on the one hand, to a better understanding of the physics of deformed cores and to operational tools to simulate these effects, and on the other hand, to very general advices for multiphysics calculations.

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