Dissertations / Theses on the topic 'Onde d'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Onde d.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Cabral, Diana Maria Capela. "Onde acaba a edição." Master's thesis, Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa, 2012. http://hdl.handle.net/10362/7539.
Para o Mestrado de Edição de Texto é relevante mencionar as edições levadas a cabo na Livraria do Teatro D. Maria II. Umas das principais razões que presidiram à escolha do Mestrado três semestres atrás foi a falta de edições de teatro com que fomos confrontados no curso. Ou não existia a peça traduzida, ou a edição tinha erros, ou era velha, ilegível, com letra pequena, com espaços indistintos, ou a linguagem precisava de ser actualizada. E poucas vezes se ouve falar de editoras que apoiem a edição teatral, pelo menos até há três ou quatro anos atrás, porque o jogo envolve dinheiro, principalmente, e uma peça tem4 um número diminuto de leitores e interessados. A Livraria privilegia o texto teatral e em obras sobre a arte do espectáculo, preenchendo o vácuo da edição teatral, facilitando a sua aquisição por aqueles que precisam das obras e por aqueles que simplesmente as desejam apreciar, estudar e compreender, dividindo-as em duas colecções, a Colecção TNMII, divulgando edições das peças levadas ao palco e a Colecção Estudos para aqueles que estudam o teatro na sua teoria e prática, editando-as em colaboração com a Quimera Editora5 e, mais recentemente, a Bicho do Mato.
Utheza, Françoise. "Modélisation de l'interaction entre un écoulement diphasique et une onde de choc." Aix-Marseille 1, 1995. http://www.theses.fr/1995AIX11040.
Hidalgo, Hervé. "Dépôt chimique en phase vapeur de couches minces d'alumine dans une post-décharge micro-onde." Limoges, 2003. http://aurore.unilim.fr/theses/nxfile/default/5bf66218-3817-4018-89e7-b6e3ca4d72a0/blobholder:0/2003LIMO0056.pdf.
Alumina thin films were deposited on silicon substrate by chemical vapor deposition using an organometallic precursor (trimethylaluminium) introduced in the afterglow of oxygen microwave plasma. Columnar and oxygen over-stoichiometric films presented hydrogen content between 4 and 25 at. % which stabilized gamma alumina at the nanometric scale. An amorphous interphase (5 nm-thick) was detected at the substrate/coating interface. Parametrical study pointed out that lower pressure, higher substrate-holder RF bias and elevated substrate temperature improved the film quality. Correlations between the gas phase composition in radiative species and films properties were complex. Statistical tools were used in order to optimize the process. The influence of the most significant parameters (pressure, RF bias, temperature, substrate/injector distance) on the film properties was studied by mean of a response surface design of experiments. Finally, principal component analyses were conducted to identify quality markers in the gaseous phase
Wisemberg, Jacques R. "Influence des ions négatifs sur la diffusion incohérente d'une onde électromagnétique dans la région D de l'ionpsphère terrestre." Doctoral thesis, Universite Libre de Bruxelles, 1985. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/213635.
Jégou, Fabrice. "Etude de la dynamique de la moyenne atmosphère de Mars à partir de données millimètriques." Paris 6, 2003. http://www.theses.fr/2003PA066166.
Nadrigny, Fabien. "Identification et exocytose d´organelles dans les astrocytes en culture: couplage de la microscopie à onde évanescente et de la décomposition spectrale." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2006. http://pastel.archives-ouvertes.fr/pastel-00002181.
Seez, William. "Rotational, progressive and periodic free-surface waves : determination and stability." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0130.
In coastal zones, waves propagating at the surface of the ocean are strongly influenced by underlying shear currents. Depth-dependent velocity profiles are generated by wind blowing at the surface and friction at the bed. Considering the Euler equations for an inviscid and incompressible fluid, along with the appropriate free-surface kinematic and dynamic boundary conditions, the interaction between a two-dimensional progressive periodic free-surface wave of permanent form and an underlying current is studied. By not assuming that the velocity field derives from a scalar potential, this work extends the linear, constant vorticity, shear model to velocity profiles defined by a class of exponential vorticity functions. The two-dimensional current profiles are first shown to be linearly stable in the absence of a free-surface perturbation. The influence of the underlying shear on waves of arbitrary amplitude and depth is then studied numerically, both in the absence and presence of capillarity. Although the celerity and potential and kinetic energy of the wave are strongly influenced by the nonlinear wave steepness parameter, the effect of vorticity is shown to be non-negligible, especially for pure gravity waves. Finally, results are presented for a linear stability analysis of these finite amplitude (2D) waves under three-dimensional perturbations. It is found that the classical classes of instability corresponding to four and five wave resonances are recovered in three-dimensions in the presence of constant or depth-dependent vorticities. Finally, a mechanism is proposed for the dominant three-dimensional instability caused by the presence of an underlying shear current
Crosnier, de Bellaistre Cécile. "Conductance et étalement d'une onde quantique dans un guide unidimensionnel : effet d'une force." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLO009/document.
A wave can be exponentially localized in a disordered medium, due to interference effects. This Anderson localization phenomenon leads to a cancellation of the conductance of a quantum fluid in 1D. However, theoretical works pointed out that an electric field may reduce or cancel this localization. We study here the effect of a force on the localization of a 1D quantum matter wave. Since both Anderson localization of an expanding wave packet and the effect of disorder on the transport between two reservoirs have been studied in ultracold atom experiments, we focus on two systems, namely the diffusion, or the transmission, of a particle.In order to calculate the transmission, we generalize a transfer matrix formalism to the presence of a, possibly inhomogeneous, force. The case of a speckle disorder as used in ultracold atom experiments is dealt with using two other analytical approaches. Our main is result is that the force can be entirely taken into account by renormalising the length with a local mean free path of the particle. For white-noise disorder, the force leads to a weaker, algebraic localization, whereas full delocalization appears for a correlated disorder. We then focus on the diffusion of a particle, using a numerical approach. A transition of delocalization of the particle for strong forces is shed into light through a power law increase of its position, whose exponent increases with the force. Moreover, we show that localization is systematically destroyed in a correlated disorder
Jacquey, Marion. "Expériences d interférométrie atomique avec l'atome de lithium." Phd thesis, Université Paul Sabatier - Toulouse III, 2006. http://tel.archives-ouvertes.fr/tel-00129507.
Vallet, Jean-Claude. "Etude de l'activité M. H. D. D'un plasma de tokamak en régime de génération de courant par une onde à la fréquence hybride inférieure." Grenoble 1, 1986. http://www.theses.fr/1986GRE10096.
Seurre, Kévin. "Proximity Effect in High-Tc d-wave Superconductor/2D Materials Heterostructures." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP002.
The emergence of innovative bidimensional materials (2D), coupled with the long-studied High- Tc d-wave superconductors, allows for the development of devices with new functionalities. It however first requires to understand the coupling between these media.This thesis, which encompasses both experiments and their theoretical description, is dedicated to this exploration with the primary objective of understanding the physics at the interface of d-wave superconductors and 2D materials, by modulating external parameters such as temperature, magnetic field, and gate voltage.The central focus of the thesis revolves around the interface between YBa₂Cu₃O₇₋ₓ (YBCO), a High-Tc d-wave superconducting oxide, and other materials, examined both theoretically and experimentally. The theoretical aspect encompasses a comprehensive review of the Blonder-Tinkham-Klapwijk (BTK) theory for d-wave superconductors, accompanied by concrete numerical calculations I carried out for publications. The experimental component involves the investigation of SN junctions using YBCO and metals. The analysis, employing both the BTK theory and Usadel's framework, reveals that while d-wave superconductivity is induced in the thin layer in proximity of YBCO, the interface between the metal and the superconducting/insulating YBCO generates s-wave superconducting correlations that compete with d-wave correlations and extend over a large portion of the metal. These first results offer a strong ground for the study of YBCO/2D materials heterostructures.I subsequently studied YBCO/graphene/YBCO junctions, in which magnetoresistance revealed modulation in the differential resistance. The systematic investigation of the magnetic field dependence circumscribes the main features of this effect. The origin of these oscillatory effects in superconducting junctions is widely discussed, pointing toward the Al'tshuler-Aronov-Spivak effect; these coherent oscillations result from interferences between normally and Andreev reflected particles in the presence of a magnetic field.This exploration of the coupling between d-wave superconductors and 2D materials is extended to the study of YBCO/MoS₂ junctions. While planar junctions similar to the ones already mentioned require further developments, I developed a new method for addressing the challenging growth of 2D materials directly atop superconducting oxides. The optimization details and a thorough analysis of transport measurements of superconducting devices fabricated with this method demonstrate excellent coupling between YBCO and MoS₂, holding promise for future proximity devices
Chpoun, Amer. "Contribution a l'etude d'ecoulements hypersoniques (m=5) sur une rampe de compression en configuration 2-d et 3-d." Paris 6, 1988. http://www.theses.fr/1988PA06A005.
CUSIN, PIERRE. "Comportement mecanique pseudo 3-d des moteurs piezo-electriques a onde progressive : vers une methodologie de conception globale. aspects technologiques de la realisation d'un prototype millimetrique." Besançon, 1998. http://www.theses.fr/1998BESA2017.
Toffano, Zeno. "Raies R. M. N. Dans les métaux organiques (TMTSF)₂PF₆ et (TMTSF)₂Cl O₄ : incommensurabilité de l'onde de densité de Spin." Paris 11, 1985. http://www.theses.fr/1985PA112326.
For the first time, in the S. D. W. State of the organic conductors (TMTSF)₂ClO₄ and (TMTSF)₂PF₆, the amplitude δ f the order parameter and the nesting vector Q̅ are determined, from a detailed analysis of the methyl proton N. M. R. Line-shape for various magnetic field orientations. In the paramagnetic metallic state, the fast rotational tunneling of the two inequivalent methyl groups splits the line into one central line and two pairs of satellites with shifts depending on field orientation, in good agreement with theory. In the S. D. W. State, the local fields due to the ordered magnetic structure lead to an important broadening of the line. By a careful analysis of the lineshape and its evolution in terms of field orientation, we prove, for both compounds, that the S. D. W. Is incommensurate; we are able to determine the local fields at each methyl site and separate the dipolar contribution from the hyperfine contact term; we deduce both the amplitude δ and wave vector Q̅ of the S. D. W. The amplitude δ = 8% +̠ 2% (in unit μB per molecule) for PF₆ is much larger than previous estimates from N. M. R. Broadening. The b* component of the nesting vector Q̅b = (0. 20 + 0. 05) b̅* (b̅* reciprocal lattice basis vector) for PF₆ is in contradiction with simple theories leading to Q̅b = 0 or Q̅b = 0. 5 b̅* but agrees with the consequences of realistic tight binding band calculations. The Q̅ vector is different in (TMTSF)₂ClO₄, in agreement with the theoretical prediction that Q̅ depends on the nature of anion and experimental conditions like pressure
Chpoun, Amer. "Contribution à l'étude d'écoulements hypersoniques (M=5) sur une rampe de compression en configuration 2-D et 3-D." Paris 6, 1988. http://www.theses.fr/1988PA066149.
Ayachi, Mohamed. "Determination de la temperature dans la mesosphere a partir de la mesure de la vitesse de phase des ondes longues sur un trajet grande distance." Caen, 1988. http://www.theses.fr/1988CAEN2021.
Bachtobji, Soumaya. "Performance Analysis of Enhancement Techniques for 3-D Cellular Networks." Thesis, Le Mans, 2019. http://www.theses.fr/2019LEMA1028.
With the explosive growth of mobile data demand, cellular networks have experienced several major evolutions, from the first generation to the present the fifth generation new radio cellular networks. These networks can cover a larger geographical area, with high network capacity, and low power consumption. For the next generation, the cellular networks consist in deploying a big number of small cells, such as femto-cells and picocells, which offers a lager zone of radio coverage. In fact, cell densification presents a simple and efficient solution to increase the network capacity, which relies on densely reusing the spectrum across a geographical area and hence brings base stations closer to users. Thus, the 3-D modeling and the performance enhancement of the increasingly heterogeneous cellular networks become important issues. The current thesis focuses on the study and the enhancement of 3-D cellular networks. The research work introduced in this thesis has two main axes. First, we focus on three-dimensional modeling of wireless communication networks. These models, not only describe the system when the blockages effect are neglected, but also capable of modeling the obstacles (such as buildings) in order to study their effect and propose solution to overcome. Second, new transmission schemes are proposed to enhance the performances of the urban wireless communication systems
Denechaud, Vincent. "Vers une étude spectroscopique de la transition d'Anderson." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLO002/document.
This manuscript summarizes the work of a thesis on Anderson's localization and transport of ultra-cold matter waves in disordered media. This is an experimental work aiming to study the Anderson transition separating the energy states of a quantum particle placed in a disordered potential into two phases: localized states and diffusive states.First, we will recall some fundamental concepts about wave localization and how such phenomenon is linked with some interference effects. Then, we will give a global description of the experimental set-up allowing to prepare the ultra-cold atomic samples used as a source of quantum matter waves, and to generate the speckle field used as disordered potential for the atoms.At the end of this introductory work, the concepts of localization introduced previously will be applied to the transport of cold atoms in a speckle field. A brief state of the art of cold-atom experiments dealing with the Anderson transition will allow us to set the limits of these works in terms of energy control on the atomic states. These limitations will then motivate the implementation of a new experimental "spectroscopic" method allowing a complete control of the energy of the atoms placed in disorder.The concept of spectral function will then be presented as a fundamental tool for characterizing energy states and for calibrating the energy reliability of the spectroscopic method. Finally, the experimental results on the measurement of spectral functions by this new spectroscopic method will show that it would be indeed possible to study the Anderson transition with a much higher energy resolution than the previous experiments
Gutlé, Claudine. "Espaces orbitalaires et théorie de la fonctionnelle de la densité : éléments pour le développement d' une approche de la chimie quantique basée sur le théorème de Hohenberg et Kohn ainsi que sur l' équation de Schrödinger, et qui conduit à des résultats exacts en suivant une systématique gouvernée par l' espace orbitalaire." Paris 7, 2003. http://www.theses.fr/2003PA077160.
Ngapasare, Arnold. "Waves in disordered and nonlinear mechanical structures." Thesis, Le Mans, 2020. http://www.theses.fr/2020LEMA1036.
This work is devoted to the theoretical and numerical study of elastic wave propagation in disordered mechanical structures. The main goal is to investigate how the localization induced by disorder is affected by nonlinearity and by the presence of rotational motion. Firstly, we study a finite granular chain and show that not only Anderson localization is broken but also energy equipartition is achieved due to the discontinuous nonlinearity which is particular to granular chains. Furthermore, we extend our studies to a micropolar lattice that supports rotational waves. We show that in the linear limit the energy spreading is facilitated both by low frequency extended waves and a set of high frequency quasiextended modes. Also, we identify a case where energy is completely localized by tuning the stiffness. Finally, for a nonlinear architected LEGO chain featuring both transverse and rotational motion we study how nonlinearity breaks Anderson localization in this polarized system. The dynamics is found to have a unique character resembling a combination of the Fermi-Pasta-Ulam Tsingou and Klein-Gordon models regarding the asymptotic dynamical behavior and chaoticity
Prat, Tony. "Localisation d'Anderson avec des atomes froids : dynamique dans le désordre et perspectives avec des modèles chaotiques." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066232/document.
This thesis theoretically investigates several effects related to Anderson localization, focusing on the context of disordered and chaotic cold-atomic systems. In cold-atomic systems, optical speckle patterns are often used to create the disorder. The resulting potentials felt by the atoms differ from Gaussian random potentials, commonly assumed in the description of condensed-matter systems. In the first part of the thesis, we discuss their specificities, with an emphasis on the spectral properties. Atom-optics experiments offer interesting possibilities, such as the possibility to directly probe the atoms inside the disordered potential. In view of these possibilities, we consider in the second part of the thesis the spreading of matter wave packets initially launched with a non-zero velocity. We find that after an initial ballistic motion, the packet center-of-mass experiences a retroreflection and slowly returns to its initial position, mimicking a boomerang. Atom-atom interactions are then introduced in a third part. We consider dilute condensed bosonic gases, and treat the interactions at the mean-field (Gross-Pitaevskii) level. Various situations are studied numerically, in particular the quantum boomerang scenario, and the dynamical spreading both in momentum and energy of matter waves prepared as plane waves. In the last part, we show that chaotic models offer interesting prospects for the study of Anderson localization. On the one hand, we present strong evidences in favor of a spinless kicked rotor in the sympletic ensemble. On the other hand, a second look at a commonly studied quasi-periodically modulated kicked rotor reveals intriguing results
Saint-Guirons, Anne-Gaëlle Barucq Hélène. "Construction et analyse de conditions absorbantes de type Diritchlet-to-Neumann pour des frontières ellipsoïdales." Pau : Université de Pau et des Pays de l'Adour, 2008. http://tel.archives-ouvertes.fr/docs/00/35/69/94/PDF/TheseAGStGuirons_HALinria.pdf.
Goy, Jérôme. "Mesures des observables tensorielles dans la réaction H(p,d)pion pour des énergies comprises entre 580 et 1300 MeV et stabilité des systèmes borroméens." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10019.
Saint-Guirons, Anne-Gaëlle. "Construction et analyse de conditions absorbantes de type Diritchlet-to-Neumann pour des frontières ellipsoïdales." Pau, 2008. http://tel.archives-ouvertes.fr/docs/00/35/69/94/PDF/TheseAGStGuirons_HALinria.pdf.
New approximate local DtN boundary conditions are proposed to be set on elliptical- or prolate-spheroidal exterior boundaries when solving respectively two- or three-dimensional acoustic scattering problems by elongated obstacles. These new absorbing conditions are designed to be exact for the first modes. They can be easily incorporated in any finite element parallel code while preserving the local structure of the algebraic system. Moreover, since the proposed conditions are applicable to exterior elliptical-shaped boundaries that are more suitable for surrounding elongated scatterers, they yield to smaller computational domains which contributes to limit computational burden. In the low frequency regime, using an on-surface radiation condition formulation, we perform the mathematical and numerical analysis of the effect of the frequency and the eccentricity values of the boundary on the accuracy of these conditions, when applied for solving radiating and scattering problems (2D and 3D). It reveals - in particular - that the new second-order DtN boundary condition retains a very good level of accuracy regardless of the slenderness of the boundary. In the high frequency regime we study the volumic formulation of the problem. It shows that it is not necessary to consider a big computational domain around the scatterer to obtain accurate results with the new second-order local DtN condition. The high frequency analysis of the reflection coefficient shows that it tends to 0 for propagative modes and it converges exponentially towards 0 for a special class of propagative, grazing and evanescent modes
Rachidi, Idris El-Idrissi. "Interactions orbitalaires en chimie organométallique et chimie du solide : structures de complexes déficients en électrons ML₅ d⁶ et de complexes acétyléniques : instabilités électroniques dans les bronzes mono et diphosphates de tungstène." Paris 11, 1989. http://www.theses.fr/1989PA112152.
Blakemore, Paul Richard. "Development and application of the one-pot Julia olefination." Thesis, University of Glasgow, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284730.
Jendrzejewski, Fred. "Quantum transport of ultracold atoms in disordered potentials." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00809290.
Ancey, Stéphane. "Résonances en géométrie elliptique : développements asymptotiques exponentiellement améliorés et levée de dégénérescence." Corte, 2000. http://www.theses.fr/2000CORT3054.
Abboud, Toufic. "Etude mathématique et numérique de quelques problèmes de diffraction d'ondes électromagnétiques." Palaiseau, Ecole polytechnique, 1991. http://www.theses.fr/1991EPXX0030.
Sandy, I. M. "Solvent induced transitions and magnetic properties of 1-D conductors." Thesis, Cranfield University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233338.
Assous, Franck. "Identification de milieux élastiques 1-D dans les équations de l'élastodynamique à deux dimensions." Paris 9, 1989. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=1989PA090035.
Fusca, Carla Jeanny [UNESP]. "VC TC D OND?: a abreviação (de distâncias) na internet." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/86580.
Este trabalho propõe investigar a abreviação em salas de bate-papo abertas (chats) da internet, frequentadas por escreventes que afirmam ter entre 15 e 20 anos. O conjunto do material é formado por duas “conversas” virtuais, com duração de 60 (sessenta) minutos cada uma. Reconhecida como uma das características do chamado “internetês”, busca-se refletir que a abreviação não consiste em mero “corte de palavras”, mas em recurso que apresenta regularidade e sistematicidade linguísticas. Esse processo é tomado como indício de (novo) gênero de discurso em emergência (BAKHTIN, 1997; MARCUSCHI, 2005). Com a finalidade de verificar os processos formadores de abreviaturas em bate-papos, ou seja, as regularidades linguísticas desse recurso, utiliza-se, como ferramenta de análise, a teoria de sílaba fonológica (SELKIRK, 1982). Acredita-se que, por meio do estudo da estrutura da sílaba, é possível avaliar que a escolha dos grafemas das abreviaturas é fundada na heterogeneidade da escrita (CORRÊA, 2004), visto que o escrevente pode se basear tanto em práticas orais/faladas quanto em práticas letradas/escritas para sua composição estrutural. Considera-se também que o funcionamento e a emergência de um modo de enunciação digital apenas são possíveis em meio a uma sociedade líquida (BAUMAN, 2004), caracterizada pela não permanência e fragilidade das relações entre os sujeitos. A consideração desses fatores parece ser indispensável para o entendimento de prática social ainda pouco (ou não) reconhecida
This research’s propose is to investigate the word’s abbreviation which appears on the internet chats, used by writers who affirm to be around 15 or 20 years old. The material’s amount is composed by two virtual “conversations” that spends around 60 minutes which one. Recognized as one characteristic of the well-known “internetês”, we consider that this abbreviation is not a simple attempt to “cut the words”, it is a resource that presents linguistics’ regularity. This process is seeing as a clue of a (new) speech genres that is borning (BAKHTIN, 1997; MARCUSCHI, 2005). In order to verify the process that forms possible abbreviations used on chats, in other words, the linguistic regularities of that resource, it is used, as a tool of analyze, the theory of phonological syllable (SELKIRK, 1982). It is believed that, based on the syllable structure’s study, it is possible to assess that the choice of the abbreviation’s graphemes is based on the writing heterogeneity (CORRÊA, 2004), since the writer can be based on oral/spoken practices or on literate/written practices. It is also considered that the operation and the emergency of a digital way to enunciate is only possible in a liquid society (BAUMAN, 2004), that is not characterized because of the fragile and permanent relationship among subjects. Considering these factors it seems to be indispensable to comprehend the social practices which are rarely (or never) recognized
Fusca, Carla Jeanny. "VC TC D OND? : a abreviação (de distâncias) na internet /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/86580.
Abstract: This research's propose is to investigate the word's abbreviation which appears on the internet chats, used by writers who affirm to be around 15 or 20 years old. The material's amount is composed by two virtual "conversations" that spends around 60 minutes which one. Recognized as one characteristic of the well-known "internetês", we consider that this abbreviation is not a simple attempt to "cut the words", it is a resource that presents linguistics' regularity. This process is seeing as a clue of a (new) speech genres that is borning (BAKHTIN, 1997; MARCUSCHI, 2005). In order to verify the process that forms possible abbreviations used on chats, in other words, the linguistic regularities of that resource, it is used, as a tool of analyze, the theory of phonological syllable (SELKIRK, 1982). It is believed that, based on the syllable structure's study, it is possible to assess that the choice of the abbreviation's graphemes is based on the writing heterogeneity (CORRÊA, 2004), since the writer can be based on oral/spoken practices or on literate/written practices. It is also considered that the operation and the emergency of a digital way to enunciate is only possible in a liquid society (BAUMAN, 2004), that is not characterized because of the fragile and permanent relationship among subjects. Considering these factors it seems to be indispensable to comprehend the social practices which are rarely (or never) recognized
Orientador: Fabiana Cristina Komesu
Coorientador: Luciani Ester Tenani
Banca: Lourenço Chacon Jurado Filho
Banca: Fernanda Correa Silveira Galli
Mestre
Sabatini, Roberto. "Simulation directe 3-D de la propagation non-linéaire des ondes acoustiques dans l'atmosphère terrestre." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC004/document.
Infrasounds are acoustic signals of frequency lower than about 20 Hz. They are generated by a large variety of natural events, such as volcanic eruptions or earthquakes, and by artificial sources, like nuclear or chemical explosions and supersonic booms. Infrasonic waves can propagate through the different atmospheric layers up to very large distances, from few hundreds to thousands of kilometres, and can potentially carry relevant information about their source. For this reason, within the framework of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), infrasound recordings are widely employed to monitor clandestine nuclear tests. Infrasound modelling has classically been based on simplified equations. Ray tracing and parabolic models have been the most commonly used techniques. Their efficiency in terms of computational cost is however obtained at the expense of generality and some of the main phenomena affecting infrasound propagation are inherently excluded by these methods. Over the past decade, progress has been made towards the simulation of acoustic propagation by directly solving the fluid dynamics equations. Understandably, this approach is expected to allow a finer description of atmospheric propagation and to lead to a better interpretation of experimental observations. In the present thesis, three main objectives have been achieved. First of all, using ray theory, a characterization of nonlinear effects and absorption induced by thermo-viscous and vibrational relaxation phenomena on the propagation of infrasonic signals generated by explosive sources has been carried out. Direct numerical simulations of the three-dimensional unsteady compressible Navier-Stokes equations have been then performed to calculate the sound field generated by an infrasonic source in a realistic atmosphere. Computations have been carried out using a low-dispersive and low-dissipative finite-difference time-domain method, for very large source amplitudes and for source frequencies of order of 0.1 Hz, up to altitudes of 140 km and ranges of few hundreds of kilometres. The scattering from small-scale inhomogeneities, of characteristic dimension of the same order as the wavelength of the infrasonic wave, has been investigated. The penetration in the shadow zone induced by diffraction phenomena at the thermospheric caustic has also been studied. Two-dimensional benchmarks specific to infrasound atmospheric propagation have been finally formulated and reference solutions have been computed. They aim to allow the assessment of the accuracy of numerical solvers as well as the evaluation of the range of validity of the classical approaches
Houard, Sylvain. "Structure de la couche d. Etude de la caustique des ondes pkp." Paris 6, 1993. http://www.theses.fr/1993PA066115.
Picon, Odile. "Traitements electromagnetiques 3-d applicables aux composants passifs microelectroniques en ondes millimetriques." Rennes 1, 1988. http://www.theses.fr/1988REN10074.
Picon, Odile. "Traitements électromagnétiques 3-D applicables aux composants passifs microélectroniques en ondes millimétriques." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37617623k.
Eaton, Brandon Michael. "One Dimensional, Transient Model of Heat, Mass, and Charge Transfer in a Proton Exchange Membrane." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/32788.
Master of Science
Nadarajah, Sivakumar. "Synthesis and reactions of a 2-cyclopenten-1-one d³ synthon." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26010.
Science, Faculty of
Chemistry, Department of
Graduate
Cuvelier, François. "Etude théorique de l'approximation de Kirchhoff pour l'équation de Maxwell, dans le complémentaire d'une réunion de convexes : Etude numérique." Paris 13, 1994. http://www.theses.fr/1994PA132013.
Plouin, Juliette. "Injection d' harmonique dans un tube à ondes progressives : amélioration de la puissance de sortie." Palaiseau, Ecole polytechnique, 2004. https://pastel.archives-ouvertes.fr/tel-00007146.
Dubois, Marc. "Contrôle de la propagation des ondes de flexion dans les plaques." Paris 7, 2014. http://www.theses.fr/2014PA077222.
Control of wave propagation in electromagnetics and acoustics experienced a large development these last years thanks to new complex media like photonic or phononic crystals and metamaterials. This work deals with the transfer of these complex media for the control of flexural waves in thin plates. These studies are the first steps towards the generalization of these new materials for elastic waves in solids. The beginning of the manuscript deals with flexural waves focusing with negative refraction using a square lattice of holes in a thin plate. The following of this work concern the time development of this negative refraction effect and shows that this system can beat the focusing diffraction limit. We introduce the blind hole or non-trough hole as a resonator for flexural wave. This resonator is the unit cell for the design and numerical study of a negative index metamaterial for flexural waves. Then a disordered arrangement of this resonator is used to study multiple scattering of flexural waves and Anderson localization effect. The second part of the manuscript introduces different alternative routes to control flexural wave propagation. We tackle the design and the experimental demonstration of a Maxwell fisheye lens for flexural waves. This setup comes from transformation optics theory. It is adapted to flexural waves by varying the plate thickness. We show that square plate with rigid boundary conditions can be used to reproduce the quantum revival effect for flexural waves. This effect characterized by the periodic reconstruction of an initial short pulse over time has been developed initially in quantum mechanics
Bernard, Alain. "Transport quantique d'ondes atomiques ultrafroides." Phd thesis, Paris 6, 2010. http://www.theses.fr/2010PA066365.
Sanches, Anderson Leonardo. "Análise de redes ópticas de alta velocidade baseadas na tecnologia CDMA e códigos bidimensionais (comprimento de onda/tempo)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-11032010-160539/.
This dissertation presents a comprehensive analysis of an OCDMA (optical code division multiple access) network based on two distinct modulation formats, namely, OOK (on-off keying) and PPM (pulse position modulation). We also investigate how each of these modulation formats performs under two distinct two dimensional (2-D) coding schemes, i.e., single-pulse per row (SPR) and multiple-pulse per row (MPR). For both cases, we have accounted for the simultaneous effect of many different dispersion and noise mechanisms (including multiple access interference, MAI) that impair the overall system performance. We have included the laser relative intensity noise (RIN) at the transmitter side, the fiber dispersive effects, such as group velocity dispersion (GVD) and first order polarization mode dispersion (PMD), as well as beat, APD, and thermal noises at the receiver side. The effect of GVD and PMD, as well as the influence of noises, on the performance of SPR and MPR codes is also investigated. Another effect studied in this dissertation is the influence of the avalanche photodetector (APD) photodetector on the beat noise of an incoherent OCDMA network. To mitigate systems noises and bit error rate (BER), we have adopted a FEC RS (255,239) algorithm in both networks investigated here. New expressions for the BER with all noises and dispersion mechanisms were also derived for the SPR and MPR code schemes. Results indicated that OOK and PPM modulation schemes without additional mechanisms to mitigate MAI and other noise effects are not sufficient to accommodate 32 simultaneous users in an error-free environment (BER < \'10 POT.-12\'). This occurs due to the already high BER at the FEC decoder input, which severely affects forward error corrections at the receiver side.
Taillandier, Cédric. "Formulation de la tomographie des temps de première arrivée à partir d'une méthode de gradient : un pas vers une tomographie interactive." Phd thesis, École Nationale Supérieure des Mines de Paris, 2008. http://pastel.archives-ouvertes.fr/pastel-00004850.
Kalghatgi, Roshan Satish. "Reconstruction techniques for fixed 3-D lines and fixed 3-D points using the relative pose of one or two cameras." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43590.
Yang, Mingming. "Development of the partition of unity finite element method for the numerical simulation of interior sound field." Thesis, Compiègne, 2016. http://www.theses.fr/2016COMP2282/document.
In this work, we have introduced the underlying concept of PUFEM and the basic formulation related to the Helmholtz equation in a bounded domain. The plane wave enrichment process of PUFEM variables was shown and explained in detail. The main idea is to include a priori knowledge about the local behavior of the solution into the finite element space by using a set of wave functions that are solutions to the partial differential equations. In this study, the use of plane waves propagating in various directions was favored as it leads to efficient computing algorithms. In addition, we showed that the number of plane wave directions depends on the size of the PUFEM element and the wave frequency both in 2D and 3D. The selection approaches for these plane waves were also illustrated. For 3D problems, we have investigated two distribution schemes of plane wave directions which are the discretized cube method and the Coulomb force method. It has been shown that the latter allows to get uniformly spaced wave directions and enables us to acquire an arbitrary number of plane waves attached to each node of the PUFEM element, making the method more flexible.In Chapter 3, we investigated the numerical simulation of propagating waves in two dimensions using PUFEM. The main priority of this chapter is to come up with an Exact Integration Scheme (EIS), resulting in a fast integration algorithm for computing system coefficient matrices with high accuracy. The 2D PUFEM element was then employed to solve an acoustic transmission problem involving porous materials. Results have been verified and validated through the comparison with analytical solutions. Comparisons between the Exact Integration Scheme (EIS) and Gaussian quadrature showed the substantial gain offered by the EIS in terms of CPU time.A 3D Exact Integration Scheme was presented in Chapter 4, in order to accelerate and compute accurately (up to machine precision) of highly oscillatory integrals arising from the PUFEM matrix coefficients associated with the 3D Helmholtz equation. Through convergence tests, a criteria for selecting the number of plane waves was proposed. It was shown that this number only grows quadratically with the frequency thus giving rise to a drastic reduction in the total number of degrees of freedoms in comparison to classical FEM. The method has been verified for two numerical examples. In both cases, the method is shown to converge to the exact solution. For the cavity problem with a monopole source located inside, we tested two numerical models to assess their relative performance. In this scenario where the exact solution is singular, the number of wave directions has to be chosen sufficiently high to ensure that results have converged. In the last Chapter, we have investigated the numerical performances of the PUFEM for solving 3D interior sound fields and wave transmission problems in which absorbing materials are present. For the specific case of a locally reacting material modeled by a surface impedance. A numerical error estimation criteria is proposed by simply considering a purely imaginary impedance which is known to produce real-valued solutions. Based on this error estimate, it has been shown that the PUFEM can achieve accurate solutions while maintaining a very low computational cost, and only around 2 degrees of freedom per wavelength were found to be sufficient. We also extended the PUFEM for solving wave transmission problems between the air and a porous material modeled as an equivalent homogeneous fluid. A simple 1D problem was tested (standing wave tube) and the PUFEM solutions were found to be around 1% error which is sufficient for engineering purposes
Parmar, Surinder Singh. "2-D non-linear seismic analysis of one-storey eccentric precast concrete buildings." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26728.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate
Goodsell, Mark Dayvon. "One loop phenomenology of type II string theory : intersecting d-branes and noncommutativity." Thesis, Durham University, 2007. http://etheses.dur.ac.uk/2915/.
Whitby, Helen Elizabeth. "The role of glycosylphospatidyl inositol phospholipase D (GDI PLD) in type one hypersensitivity." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251585.