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Response and Failure of Adhesively Bonded Automotive Composite Structures under Impact LoadsSimon, Joshua Cameron 04 February 2005 (has links)
An experimental technique for conducting low speed impact of adhesively bonded automotive composite joints is presented. Based on the use of a modified drop tower, mode I, II, and mixed mode values for critical energy release rate were determined for a composite/epoxy system and used to create a fracture failure envelope. Because load measurements become erratic and unreliable at higher test rates, displacement-based relationships were used to quantify these energy release rates. Displacement data was collected with an imaging system that utilized edge detection to determine displacement profiles, end displacements, and opening displacements where applicable. Because of the resolution of the image-based approach used, determining crack length experimentally was extremely difficult. As a result, numerical methods were developed to objectively determine the crack length based on the available experimental data in mode I, II, and mixed mode I/II configurations.
This numerical method uses a nonlinear fit to determine mode I crack lengths and a theoretical model based on cubic equations for mode II and mixed-mode I/II, where the coefficients of the equations are determined by using both boundary and transition conditions that are a result of the test setup. A double cantilever beam (DCB) geometry was chosen to collect mode I data, an end-loaded split (ELS) geometry was used for mode II, and a single leg bend (SLB) geometry was used for mixed-mode I/II. These geometries were used to determine the fracture characteristics of adhesively bonded automotive composites to create fracture failure envelopes as well as provide mode I, II, and mixed-mode I/II data to be used in finite element models.
The chosen adhesive exhibited unstable, stick-slip crack growth, which resulted in very few data points being collected from each static DCB specimen as well as drastic drops in energy release rate between initiation and arrest points. Unstable growth also created issues in dynamic testing, as data points surrounding these "stick-slip" events were lost due to the insufficient sampling rate of the available imaging system.
Issues also arose with differences between thick and thin composite adherend specimens. These differences could result from additional curing in thick adherend composite specimens due to the adherends retaining heat. DSC testing was conducted on uncured adhesive using a 2, 5, and 10 minute hold at the cure temperature, and significant additional curing was observed between the two and five minute cures. Due to the difference in relative stiffness between the 12 and 36 ply composite, the local loading rate at the crack tip was lower in the 12 ply adherends, possibly allowing for a larger plastic zone and thus a higher energy release rate. As a result, tests were conducted on 36 ply composite specimens at rates of 1 mm/min and 0.1 mm/min to determine if there were loading rate effects. This testing showed that higher initiation energy relase rates were found at the lower test rate, thus reinforcing the local loading rate theory.
Due to issues with plastic deformation in aluminum adherends, mode II and mixed-mode I/II data were collected using only composite adherends. Only one data point was collected per specimen as the crack propagated directly into the composite after initiating from the precrack, thus multiple tests were conducted to collect sufficient data for constructing a failure envelope.
Once mode I, II and mixed-mode I/II fracture data was collected, a fracture failure envelope was created. This failure envelope, combined with a predetermined factor of safety, could provide some of the necessary tools for design with this adhesive/composite system. / Master of Science
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Probabilistic Characterization of Bond Behavior at Rebar-concrete Interface in Corroded RC Structures: Experiment, Modeling, and ImplementationSoraghi, Ahmad January 2021 (has links)
No description available.
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[en] COSSERAT RODS AND THEIR APPLICATION TO DRILL-STRING DYNAMICS / [es] ESTRUCTURAS UNIDIMENSIONALES DE COSSERAT APLICADAS A LA DINÁMICA DE COLUMNAS DE PERFORACIÓN / [pt] ESTRUTURAS UNIDIMENSIONAIS DE COSSERAT APLICADAS À DINÂMICA DE COLUNAS DE PERFURAÇÃOHECTOR EDUARDO GOICOECHEA MANUEL 13 June 2023 (has links)
[pt] Nesta tese, a teoria das hastes de Cosserat é revisitada e aplicada à
dinâmica de coluna de perfuração. O objetivo é estudar o comportamento
dessas estruturas dentro de poços de petróleo curvos. Para atingir este objetivo,
um modelo estrutural determinístico é construído onde as tubos de perfuração
(drill-pipes) e o conjunto de fundo (bottom hole assembly) são considerados
como uma estrutura unidimensional de Cosserat. Em seguida, é desenvolvida
uma estratégia para tratar o contato lateral em poços com configuração
curvilínea. Depois disso, o problema de contorno livre é tratado mediante
uma estratégia que considera como a condição de borda evolui à medida que
a estrutura de perfuração avança. Isto é feito mediante uma formulação de
interação broca-rocha que deve considerar a dinâmica de corte. Para isso, uma
equação extra, de advecção, é resolvida junto com as equações de movimento
de Cosserat. Em seguida, alguns casos de aplicação são apresentados. Numa
primeira instancia, alguns elementos do problema são avaliados separadamente.
Seguidamente, eles são integrados e analisados de forma conjunta. Por exemplo,
primeiramente uma coluna de perfuração sem contato de fundo (off-bottom)
é simulada, ou seja, sem contato broca-rocha, para estudar o comportamento
e a implementação da estratégia para o contato lateral. Aqui também são
calibrados alguns dos parâmetros do modelo de atrito. Em seguida, a estratégia
para contabilizar o corte na rocha é implementada em um modelo 2-DOF de
baixa dimensão e em um semi-discreto onde a dinâmica de torção é modelada
como uma equação de onda. Os resultados mostram que o uso de abordagens
contínuas resulta mais apropriade que aquelas onde se utilizam modelos de
baixa dimensãom, particularmente quando são consideradas colunas longas,
e quando há interesse em analisar não apenas o comportamento da broca,
mas também o comportamento do sistema mecânico ao longo dos tubos de
perfuração. Isso é reforçado por outro exemplo onde a dinâmica de corte
é combinada com a formulação de Cosserat. Observações semelhantes do
ponto de vista qualitativo são encontradas. Resumindo os resultados obtidos,
as diferenças nas previsões dadas pelos modelos de baixa dimensão e o
de unidimensional de Cosserat justificam o desenvolvimento e aplicação da
abordagem com esta formulação em estruturas de perfuração. Finalmente, a
modo de introduzir outro aspecto importante em colunas de perfuração e que
pode ser uma linha de pesquisa para continuar o trabalho, a variabilidades
presente em elementos como rocha, inclui-se um caso de aplicação considerando
um poço horizontal e um campo estocástico de atrito. / [en] In this thesis, the theory of Cosserat rods is applied to the dynamics of
drill-strings. The main objective is to evaluate the behaviour of these strings
when they move within curved wells. To achieve this goal, a deterministic
structural model is constructed, where the drill-pipes and the bottom hole
assembly are taken as a Cosserat rod. Next, a strategy to deal with the
lateral contact in curved well configurations is developed. After that, the free
boundary problem is assessed: while drilling, the boundary changes due to
cutting, modifying the position of the soil and, consequently, changing the bit-rock interaction forces. For this reason, a bit-rock model that can account for
the cutting dynamics is adopted, in which an extra advection equation is solved
together with the equations of motion of the Cosserat rod. Next, application
cases are provided. First, some effects included in the model are tested in
isolation, such as the lateral friction, the lateral contact, and the cutting.
After that, they are all combined. In the first analysis, an off-bottom string is
simulated, i.e. without contact at the bit. This allows testing the formulation
associated with the lateral contact. Also, the calibration of the lateral friction
parameters is made. Following that, the strategy to account for the cutting
at the bit is implemented in a low-dimensional 2-DOF model, and in a semi-discrete model with a continuous wave equation for the torsional dynamics.
The results show that the use of continuous approaches is more appropriate
than low-dimensional models. Especially when long columns are considered,
and when there is interest in understanding not only the behaviour at the bit
but also along drill-pipes. This finding is reinforced by another application
where the cutting dynamics are combined with the Cosserat rod formulation.
Again, similar observations from a qualitative point of view are found. Overall,
the differences in the results between the lumped low-dimensional models and
the continuous Cosserat rod justify the development and application of the
Cosserat approach to drilling structures. Finally, an introductory stochastic
analysis concerning the variability of the rock is presented as an introduction
to a future line of research, where stochasticity is included. / [es] En esta tesis, la teoria de Cosserat para elementos unidimensionales es
revisitada y aplicada a la simulación de columnas de perforación. El objetivo
es estudiar el comportamiento de estas estructuras en pozos de geometría
curva. Para alcanzar este objetivo se construye un modelo determinístico.
En este modelo, los caños de perforación (drill-pipes) y el conjunto de fondo
(bottom hole assembly) son modelados como una estructura unidimensional de
Cosserat. Seguidamente, una estrategia para tratar con el contacto lateral en
pozos curvos es desarrollada. Luego, el problema de frontera libre es estudiado:
durante la perforación, la condición de borde cambia debido al cambio del perfil
altimétrico del terreno, alterando su posición y consecuentemente las fuerzas
asociadas a la interacción broca-roca. Por esta razón, se decide utilizar un
modelo de interacción broca-roca que tiene en cuenta la dinámica del corte.
En este abordaje una ecuación extra, la ecuación de advección, es resuelta en
forma acoplada con las ecuaciones del movimiento de la estructura de Cosserat.
Algunos ejemplos de aplicación son presentados. En una primera instancia,
algunos de los elementos del problema son estudiados en forma aislada. Luego
combinados en un modelo completo. Por ejemplo, el caso de una columna sin
contacto de fondo (off-bottom) es tratado para evaluar el comportamiento y la
implementación de la estrategia mencionada para detectar el contacto lateral.
Además, se efectúa la calibración de alguno de los parámetros relacionados
con la fricción lateral. Luego, la estrategia para considerar el corte en la punta
es implementada en un modelo de 2-DOF, y en otro semi-discreto donde se
considera un modelo de ecuación de onda para la dinámica torsional. Los
resultados muestran que el uso de formulaciones continuas es más apropiado
que aquellas formulaciones donde se utilizan modelos de dimensiones reducidas,
particularmente cuando se estudia columnas largas donde el interés se centra
en entender no solo el comportamiento de la broca sino también a lo largo de
la tubería. Este resultado es reforzado por otro caso de aplicación en donde
se combina la dinámica de corte con un modelo de Cosserat. Observaciones
similares son vistas en el comportamiento cualitativo de la solución. En
resumen, las diferencias observadas en los diferentes ejemplos de aplicación
entre los modelos de dimensiones reducidas y el modelo continuo de Cosserat
justifican el desarrollo y la aplicación de la teoría de Cosserat a estructuras de
perforación. Finalmente, dado que uno de los objetivos planteados también es
considerar la variabilidad en algunos elementos como ser las propiedades de la
roca, un caso de aplicación considerando un pozo horizontal es mostrado.
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A micromechanical model for the nonlinearity of microcracks in random distributions and their effect on higher harmonic Rayleigh wave generationOberhardt, Tobias 07 January 2016 (has links)
This research investigates the modeling of randomly distributed surface-breaking microcracks and their effects on higher harmonic generation in Rayleigh surface waves. The modeling is based on micromechanical considerations of rough surface contact. The nonlinear behavior of a single microcrack is described by a hyperelastic effective stress-strain relationship. Finite element simulations of nonlinear wave propagation in a solid with distributed microcracks are performed. The evolution of fundamental and second harmonic amplitudes along the propagation distance is studied and the acoustic nonlinearity parameter is calculated. The results show that the nonlinearity parameter increases with crack density and root mean square roughness of the crack faces. While, for a dilute concentration of microcracks, the increase in acoustic nonlinearity is proportional to the crack density, this is not valid for higher crack densities, as the microcracks start to interact. Finally, it is shown that odd higher harmonic generation in Rayleigh surface waves due to sliding crack faces introduces a friction nonlinearity.
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Direct grid connection and low voltage ride-through for a slip synchronous-permanent magnet wind turbine generatorHoffmann, Ulwin 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The slip synchronous-permanent magnet generator (SS-PMG) is a direct-driven, direct-to-grid generator
for wind turbine applications. This investigation focuses on achieving automated grid connection and
low voltage ride-through for a small-scale SS-PMG. To reduce cost and complexity, components such
as blade pitch controllers and frequency converters are avoided. Instead, electromagnetic braking is
employed to control turbine speed prior to grid synchronisation and compensation resistances are used
to facilitate grid fault ride-through.
The conditions under which the SS-PMG can be successfully synchronised with the grid are determined,
indicating a need for speed control. An evaluation of electromagnetic braking strategies reveals
that satisfactory speed control performance can be achieved when employing back-to-back thyristors to
switch in the braking load. Simulations show that controlled synchronisation can be executed successfully
under turbulent wind conditions. All controllable parameters are held within safe limits, but the
SS-PMG terminal voltage drop is higher than desired.
Compensation is developed to allow the SS-PMG to ride through the voltage dip profile specified by
the Irish distribution code. It is found that a combination of series and shunt resistances is necessary to
shield the SS-PMG from the voltage dip, while balancing active power transfer. The flexibility offered by
thyristor switching of the shunt braking load is instrumental in coping with turbulent wind conditions
and unbalanced dips. The South African voltage dip profile is also managed with conditional success.
Following on from the theoretical design, the grid connection controller is implemented for practical
testing purposes. Protection functions are developed to ensure safe operation under various contingencies.
Before testing, problems with the operation of the thyristors are overcome.
Practical testing shows that grid synchronisation can be undertaken safely by obeying the theoretically
determined conditions. The speed control mechanism is also shown to achieve acceptable dynamic
performance. Finally, the SS-PMG is incorporated into a functioning wind turbine system and automated
grid connection is demonstrated under turbulent wind conditions.
Future investigations may be focused on optimal control strategies, alternative solid-state switching
schemes, and reactive power control. Low voltage ride-through should also be optimised for the South
African dip profile and validated experimentally. / AFRIKAANSE OPSOMMING: Die glip-sinchroon permanente magneet generator (GS-PMG) is ‘n direkte dryf, direkte netwerkgekoppelde
generator vir windturbine toepassings. Hierdie ondersoek fokus op die bereiking van ’n
ge-outomatiseerde netwerkkoppeling en lae spanning deurry vir ‘n kleinskaalse GS-PMG. Om kostes
en kompleksiteit te verminder, word komponente soos lemsteekbeheerders en frekwensie-omsetters
vermy. In plaas daarvan word elektromagnetiese remwerking gebruik om die turbine spoed, voorgaande
net-werksinchronisasie, te beheer, en word kompensasieweerstande gebruik om netwerkfoutdeurry
te handhaaf.
Die omstandighede waaronder die GS-PMG suksesvol met die netwerk gesinchroniseer kan word, is
vasgestel en dit het die behoefte aan spoedbeheer uitgewys. ‘n Evaluering van elektromagnetiese remstrategië
wys uit dat ’n bevredigende spoedbeheervermoë verkry kan word as anti-parallelle tiristors
gebruik word om die remlas te skakel. Simulasies wys dat beheerde netwerksinchronisasie suksesvol
uitgevoer kan word, selfs onder turbulente windtoestande. Alle beheerbare parameters is binne veilige
perke gehou, maar die GS-PMG se klemspanningsval is gevind as hoë as verwag.
Kompensasie is ontwikkel om die GS-PMG toe te laat om deur die spanningsvalprofiel, soos gespesifieer
deur die Ierse distribusiekode, te ry. Dit is gevind dat ‘n kombinasie van serie- en parallelle
weerstande nodig is om die GS-PMG teen die spanningsval te beskerm, terwyl aktiewe drywingsoordrag
gebalanseer word. Die buigbaarheid wat verkry word met die tiristorskakeling van die parallele
weerstand is noodsaaklik in die hanteering van turbulente windtoestande en ongebalanseerde spanningsvalle.
Die Suid-Afrikaanse spanningsvalprofiel is ook met voorwaardelike sukses hanteer.
In opvolg van die teoretiese ontwerp is die netwerkkoppelingsbeheerder vir praktiese toetsdoeleindes
in werking gestel. Beskermingsfunksies is ontwikkel om veilige werking onder verskeie gebeurlikhede
te verseker. Die probleme met die werking van die tiristors is oorkom voor die aanvang van die
toetse.
Die praktiese toetse bewys dat netwerksinchronisasie veilig gedoen kan word deur die teoretiese
bepaalde voorwaardes te volg. Dit is ook getoon dat met die spoedbeheermeganisme aanvaarbare dinamiese
gedrag verkry kan word. Ten laaste is die GS-PMG in ‘n werkende windturbinestelsel geïnkorporeer
en outomatiese netwerkkoppeling is onder turbulente windtoestande gedemonstreer.
Toekomstige ondersoeke kan toegespits word op optimale beheerstrategië, alternatiewe vaste toestand
skakelingskemas en reaktiewe drywingsbeheer. Lae spanning deurry moet nog vir die Suid-
Afrikaanse spanningsprofiel ge-optimeer en eksperimenteel bevestig word.
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Novel electrocatalytic membrane for ammonia synthesisKlinsrisuk, Sujitra January 2010 (has links)
Novel ceramic membrane cells of BaCe₀.₅Zr₀.₃Y₀.₁₆Zn₀.₀₄O[subscript(3-δ)] (BCZYZ), a proton-conducting oxide, have been developed for electrocatalytic ammonia synthesis. Unlike the industrial Haber-Bosch process, in this work an attempt to synthesise ammonia at atmospheric pressure has been made. The membrane cell fabricated by tape casting and solution impregnation comprises of a 200 μm-thick BCZYZ electrolyte and impregnated electrode composites. Electrocatalysts for anode and cathode were investigated. For the anode, the co-impregnation of Ni and CeO₂ provided excellent electrode performance including high catalytic activity, sintering stability and compatibility with the BCZYZ electrolyte. The best composition was the mixture of 25 wt% NiO and 10 wt% CeO₂. A symmetrical cell prepared with this electrode composition revealed low polarisation resistances of 1.0 and 0.45 Ωcm² in humidified 5% H₂/Ar at 400 and 500 °C, respectively. For the cathode, 25 wt% of impregnated Fe oxide provided a satisfactory performance in non-humidified N₂ atmosphere. Significant amounts of ammonia were produced from the single cell with Ni-CeO₂ anode and Fe oxide cathode at 400-500 °C under atmospheric pressure. Ammonia formation rate was enhanced by Pd catalyst addition and electrochemical performance was improved by Ru addition. The highest ammonia formation rate of 4 x 10⁻⁹ mols⁻¹cm⁻² was attained using the cell with a Pd-modified Fe cathode at 450 °C. The formation reaction of ammonia typically consumed around 1-2.5 % of total applied current while most of the applied current was employed in H⁺ reduction. The total current efficiency of around 90-100 % could be obtained from the membrane cells.
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Rôle du processus de forabilité des roches dans les vibrations de torsion des systèmes de forage pétrolierPelfrene, Gilles 20 December 2010 (has links) (PDF)
Les outils de forage de type PDC peuvent subir d'intenses variations de leur vitesse de rotation, qui perturbent le déroulement des opérations de forage. Ce phénomène auto-entretenu, appelé stick-slip, se produit dans une variété de contextes de forage actuels et on admet généralement que l'instabilité est due à la décroissance du couple à l'outil suivant la vitesse de rotation. De nombreux dispositifs ont été introduits pour limiter son apparition, mais ni la cause physique de cette décroissance, ni le rôle joué par l'outil n'ont été clairement identifiés jusqu'à présent. Cette thèse vise à étudier, expérimentalement et théoriquement, la réponse mécanique des outils PDC lorsqu'ils sont soumis à des variations de leur vitesse de rotation. Une campagne d'essais de forabilité des roches a montré que les efforts qui s'exercent autant sur les outils PDC, que sur les taillants qui les composent, dépendent significativement de la vitesse de rotation. On a attribué ce phénomène au cisaillement dynamique d'une couche de roche broyée, compactée à l'interface entre le taillant et la saignée. Un modèle semi-empirique d'interaction dynamique outil-roche a été ajusté sur ces expériences pour prédire la réponse dynamique d'outils réels, puis validé à partir des essais sur outils de forage à l'échelle 1. Il a été couplé à un algorithme décrivant la dynamique en torsion des garnitures de forage pour calculer le risque de stick-slip associé. Le modèle développé explique non seulement, pourquoi le couple à l'outil diminue avec la vitesse de rotation mais aussi montre qu'il est possible de réduire le risque de stick-slip en sélectionnant la conception d'outil PDC appropriée.
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Intégration de matériaux oxydes innovants dans une cellule IT-SOFCMorandi, Anne 04 April 2013 (has links) (PDF)
Cette thèse vise à évaluer le potentiel d'un nouveau couple cathode / électrolyte pour une application en IT-SOFC (700°C), par le biais de l'élaboration et du test de cellules à anode support de configuration planaire. Les matériaux concernés sont l'électrolyte BaIn0.3Ti0.7O2.85 (BIT07), de structure perovskite, et les nickelates de terres rares Ln2-xNiO4+ (LnN, Ln = La, Nd, Pr) en tant que cathodes ; ces matériaux ont montré des propriétés prometteuses dans des travaux préliminaires effectués à l'IMN et l'ICMCB. La première partie de cette thèse porte sur la mise en place d'un protocole d'élaboration de cellules complètes utilisant des techniques bas coûts et industrialisables (cellules de taille 3 x 3 cm2) : l'anode Ni / BIT07 a été élaborée par coulage en bande, l'électrolyte BIT07 par vacuum slip casting et les cathodes par sérigraphie. Les mesures électrochimiques réalisées sur une première génération de cellules ont mis en évidence la nécessité d'ajouter une couche barrière de GDC entre les cathodes LnN et l'électrolyte BIT07. Les meilleures performances ont été obtenues pour une cellule BIT07 / Ni | BIT07 | GDC | PrN, avec une densité de puissance à 700°C et 0.7 V de 176 mW cm-2 pour une faible résistance de polarisation de 0. 29 Ω cm2. La principale limitation des performances a été identifiée comme étant la résistance interne du banc de test, donnant lieu à des valeurs de résistances séries anormalement élevées. Cette cellule a été opérée avec succès durant plus de 500 heures sous courant, avec néanmoins une vitesse de dégradation extrapolée élevée de l'ordre de 27% / kh.
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Multiscale modelling and simulation of slip boundary conditions at fluid-solid interfacesPham, Thanh Tung 25 September 2013 (has links) (PDF)
In most applications concerning a fluid flowing over a solid surface, the no-slip velocity condition was widely used because it is simple and produces the results in agreement with experiments. However, this dynamical boundary condition is not appropriate when the flow under consideration is at a micro or nano length scale.In order to model this effect at the macroscopic scale, the Navier boundary conditions have been introduced, with the slip length as a parameter. When the fluid is a gas, this length is related to the tangential momentum accommodation coefficient (TMAC) and the mean free path, according to the Maxwell model. The aim of this work is to systematically address this model using a multi-scale approach and to extend it by incorporating both the morphology and the anisotropy of a surface. The thesis consists of five chapters. In Chapter 1, the basics of the kinetic theory of gases, the Boltzmann equation and related solutions (Navier-Stokes-Fourier, Burnett, Grad, Direct Simulation Monte Carlo ...) are briefly presented. The models of gas-wall interaction and slip models introduced in the fluid mechanics are also recalled. The chapter ends with a description of the computational method used for the molecular dynamics simulations performed in this work. Chapter 2 is dedicated to the development of a simple technique to simulate the pressure driven flows. The principle is to rely on the atomistic formulas of the stress tensor (Irving Kirkwood, Method of Plane, Virial Stress) and to modify the periodic conditions by maintaining the difference between the kinetic energy of the ingoing and outgoing particles of the simulation domain. Several types of channels are studied with this technique. The results (temperature, velocity ...) are discussed and compared. Chapter 3 deals with the study of the gas-wall interaction potential by the ab-initio method. The code CRYSTAL 09 is used to obtain the potential between an atom of argon (Ar) and a surface of platinum (Pt) <111> as a function of distance. Then the gas-wall potential is decomposed into binary potential and approached by an analytic function. This function is then implemented in a MD code to simulate the gas-wall collisions and determine the TMAC coefficient. In Chapter 4, the effect of morphology is studied. The multi-body Quantum Sutton Chen (QSC) potential is used for Pt <100> solid and the binary potential proposed in the previous chapter for the Ar-Pt couple is employed. The QSC potential is needed to reproduce the surface effects that affect the final results. Different surfaces are treated : smooth, nanostructured surface and, random surface obtained by Chemical vapor deposition (CVD). The TMAC is determined using a generalized approach, i.e. depending on the angle of incident flux of gas atoms on the surface. The surface anisotropy and the scattering kernel are also examined. In Chapter 5, we propose a model of anisotropic slip for fluids based on accommodation tensor. The model is obtained by the analytical approximate calculations developed in the framework of the kinetic theory. We thus generalize Maxwell's equation by showing that the slip length tensor is directly related to the accommodation tensor. The model is in good agreement with the MD results. Thanks to our MD simulations, we develop a suitable technique for reproducing the anisotropy of the accommodation tensor. The thesis ends with a conclusion section in which we suggest some perspectives for a continuation of this work
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Sociétés de fictionsTremblay, Samuel 07 1900 (has links)
Le concept des Sociétés de fictions élaboré dans le cadre de ce mémoire vise l’exploration de la médiation à l’ère du numérique. Pour penser les modalités de fictions littéraires avec l’idée qu’elles puissent former des sociétés distinctes, ce travail d’analyse propose d’examiner diverses fictions, plus précisément des expressions gothiques américaines en littérature contemporaine, afin d’en extraire un mode de pensée significatif. Dans le dessein d’analyser la manière dont ces fictions se relient entre elles, cette recherche se focalise sur le rapport qu’entretient la fiction littéraire avec la technologie ainsi qu’avec divers modes de diffusion et de médiation. Afin de comprendre comment les mécanismes du discours positionnent des œuvres de fictions les unes par rapport aux autres, ces fictions individuées seront d’abord examinées au sein d’une société qui leur est propre. Ceci mènera à exposer en quoi et comment les rapports qu’entretient l’humain avec la littérature et la technologie se reconfigurent par le biais de nouvelles formes de médiations. La présente réflexion se penche ainsi sur les modes d’interactions des fictions qui s’organisent en sociétés afin de pouvoir analyser comment le glissement du paradigme de l’imprimé et des supports matériels, à l’âge du numérique, peut se traduire par une manière inédite de penser notre relation au littéraire. En somme, cette réflexion sur la mobilité des formes et des plateformes liées aux fictions et à leur société devrait permettre de mieux analyser les individus qui inventent et consomment ces fictions, leur univers social ainsi que leur rapport intime à la technologie et ses médiations. Ces sociétés de fictions deviennent alors une clé pour comprendre notre rapport à la virtualisation de nos univers sociaux. Entre les sociétés de fictions et les sociétés des Hommes se noue un lien substantiel laissant entrevoir une véritable co-évolution de ces univers distincts. Les principales œuvres de fiction étudiées et citées seront celles du romancier et scénariste américain Bret Easton Ellis, plus précisément les romans Less Than Zero et Imperial Bedrooms. Il sera également question de la série télévisuelle Twin Peaks, diffusée sur la chaîne ABC en 1990 et réalisée par David Lynch, ainsi que d’une nouvelle de John Cheever, The enormous radio, parue en 1947, dans le New Yorker. / The concept of Societies of fictions developed inside the framework of this Masters thesis aims to explore the mediation at the digital age. The main idea is to think the terms of narrative fiction with the idea that each one may be part of societies. To do so, this analytical work intends to examine various fictions, specifically some examples of the American Gothic in contemporary literature, to extract a significant thought mode. In attempt to analyze how these fictions connect to each other, this piece of research focuses also on the relationship that fiction maintains with technology, including various modes of dissemination. To understand how narrative mechanisms contribute to positioning those fictions relative to each other, they will be approached as if they formed a society of their own. This strategy will lead us to revisit past tradition in a critical vein, and it will also provide an entry into the ways in which and how relations among human, literature and technology are reconfigured through new forms of mediation. By emphasizing the idea that fictions are organized into societies, we are in a better position to describe the paradigm shift from printed to digital media, and to examine how it transforms our relationship to narrative fiction in general. On balance, this discussion on mobility forms and fictions related platforms and their society should ultimately permit a better analyze of individuals who invent and consume these fictions, their social world and their intimate relationship with technology and mediations. As a result, Societies of fictions can become a key element to understand our relationship with the virtualization of our social universe. Between societies of fictions and human societies, a substantial connection can be drawn in the form of a co-evolutionary process. The main works studied and cited will be those of the American novelist and screenwriter Bret Easton Ellis, more specifically Less Than Zero and Imperial Bedrooms. The television serial drama Twin Peaks, which aired on the ABC channel in 1990 and was directed by David Lynch, will also be discussed, as well as a John Cheever’s short story, The Enormous Radio, originally published in 1947 in The New Yorker.
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