Dissertations / Theses on the topic 'Dimension du contact'
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Koert, Otto van. "Open books for contact five-manifolds and applications of contact homology." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976606925.
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Hadjar, Mohamed. "Sur les structures de contact invariantes en dimension trois." Mulhouse, 1992. http://www.theses.fr/1992MULH0226.
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Ce travail concerne le problème de prolongements et de classification des structures de contact invariantes sur les fibrés principaux en cercles de dimension trois. On montre qu'il existe sur un tel fibré une forme de contact invariante induisant une forme invariante donnée sur une surface invariante plongée, si et seulement si elle ne s'annule pas simultanément avec sa différentielle. D'autre part, on définit un invariant réel associé à une structure de contact régulière définie au voisinage du bord d'une variété connexe de dimensions trois, et on montre que la non-nullité de cet invariant réel est la condition nécessaire et suffisante pour pouvoir prolonger la structure sur toute la variété en une structure de contact régulière
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Massot, Patrick. "Sur quelques aspects riemanniens des structures de contact en dimension trois." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2008. http://tel.archives-ouvertes.fr/tel-00347962.
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Cette thèse aborde l'étude de quelques propriétés riemanniennes des structures de contact en dimension trois et de leurs relations avec la topologie de ces structures. Dans la première partie on décrit diverses notions de courbure de champs de plans sur des variétés riemanniennes de dimension trois en comparant plusieurs approches préexistantes mais souvent mal connues. Dans la deuxième partie on présente les techniques topologiques d'étude des structures de contact en dimension trois. Enfin la troisième partie, qui rassemble l'essentiel des résultats nouveaux de cette thèse, est une étude des structures de contact géodésibles en dimension trois à l'aide des outils présentés dans la deuxième partie.
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Massot, Patrick. "Sur quelques propriétés riemanniens des structures de contact en dimension trois." Lyon, École normale supérieure (sciences), 2008. http://www.theses.fr/2008ENSL0498.
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Cette thèse aborde l'étude de quelques propriétés riemanniennes des structures de contact en dimension trois et de leurs relations avec la topologie de ces structures. Dans la première partie on décrit diverses notions de courbure de champs de plans sur des variétés riemanniennes de dimension trois en comparant plusieurs approches préexistantes mais souvent mal connues. Dans la deuxième partie on présente les techniques topologiques d'étude des structures de contact en dimension trois. Enfin la troisième partie, qui rassemble l'essentiel des résultats nouveaux de cette thèse, est une étude des structures de contact géodésibles en dimension trois à l'aide des outils présentés dans la deuxième partieThis thesis study some riemannian properties of contact structures on 3--manifolds and their relationship with the topology of such structures. In the first part we describe various notions of curvature of plane fields on riemannian 3--manifolds by comparing several not well known approaches. In the second part we describe the topological techniques applied to the study of contact structures on 3--manifolds. The third part, which contains most of the new results of this thesis, is a study of geodesible contact structures on 3--manifolds using the tools described in the second part
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Colin, Vincent. "Sur la stabilite, l'existence et l'unicite des structures de contact en dimension trois." Lyon, École normale supérieure (sciences), 1998. http://www.theses.fr/1998ENSL0096.
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On demontre dans un premier temps que sur une variete fermee de dimension trois, deux structures de contact c#0-proches sont isotopes. On etudie ensuite le comportement des structures de contact tendues vis-a-vis d'operations de chirurgie le long de surfaces. On prouve ainsi que toute variete obtenue par chirurgie d'indice un sur une variete de contact tendue est naturellement une variete de contact tendue. On montre alors que lorsqu'on recolle deux varietes de contact tendues de dimension 3 le long de deux tores incompressibles, la variete resultante est tendue pourvu que les structures de depart soient universellement tendues et les tores quasi pre-lagrangiens. De plus, on construit un exemple qui montre que sans cette derniere hypothese, la nouvelle variete peut etre vrillee. En guise d'application, on combine ces techniques de chirurgie avec un resultat recent de y. Eliashberg et w. Thurston pour construire une structure de contact tendue sur une nouvelle classe de spheres d'homologie toroidales. On obtient pour conclure un resultat de chirurgie pour toutes les surfaces a bord. Dans la derniere partie, on demontre que la torsion, un invariant introduit par e. Giroux et associe a toute classe d'isotopie de plongements du tore : t#2 v dans une variete de contact (v,), est finie pour peu que la structure soit universellement tendue et que satisfasse a une condition raisonnable. Ce resultat permet de construire de nombreux exemples de varietes qui admettent une infinite de structures de contact tendues deux a deux non isotopes.
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Colin, Vincent. "Sur la géometrie des structures de contact en dimension trois : stabilité, flexibilité et finitude." Habilitation à diriger des recherches, Université de Nantes, 2002. http://tel.archives-ouvertes.fr/tel-00002138.
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Kudawoo, Ayaovi Dzifa. "Problèmes industriels de grande dimension en mécanique numérique du contact : performance, fiabilité et robustesse." Phd thesis, Université de Provence - Aix-Marseille I, 2012. http://tel.archives-ouvertes.fr/tel-00773642.
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Ce travail de thèse concerne la mécanique numérique du contact entre solides déformables. Il s'agit de contribuer à l'amélioration de la performance, de la fiabilité et de la robustesse des algorithmes et des modèles numériques utilisés dans les codes éléments finis en particulier Code_Aster qui est un code libre développé par Électricité De France (EDF) pour ses besoins en ingénierie. L'objectif final est de traiter les problèmes industriels de grande dimension avec un temps de calcul optimisé. Pour parvenir à ces objectifs, les algorithmes et formulations doivent prendre en compte les difficultés liées à la mécanique non régulière à cause des lois de Signorini-Coulomb ainsi que la gestion des non linéarités dûes aux grandes déformations et aux comportements des matériaux étudiés. Le premier axe de ce travail est dédié à une meilleure compréhension de la formulation dite de " Lagrangien stabilisé " initialement implémentée dans le code. Il a été démontré l'équivalence entre cette formulation et la formulation bien connue de " Lagrangien augmenté ". Les caractéristiques mathématiques liées aux opérateurs discrets ont été précisées et une écriture énergétique globale a été trouvée. Une réflexion a été mise en oeuvre en vue de renforcer de manière faible la condition cinématique sur la normale dans la zone de contact via les techniques d'optimisation sans contraintes. La nouvelle formulation est dite de " Lagrangien augmenté non standard ". Trois nouvelles stratégies basées sur le Lagrangien augmenté ont été implémentées. Il s'agit de la méthode de Newton généralisée : c'est une méthode d'optimisation qui permet de résoudre toutes les non linéarités du problème en une seule boucle d'itérations. La méthode de Newton partielle est une méthode hybride entre la méthode historique du code appelée méthode de point fixe et la méthode de Newton généralisée. Enfin, on a mis en place une façon originale de traiter le cyclage : ce phénomène apparaît souvent au cours de la résolution du problème et il entraîne la perte de convergence des algorithmes. La stratégie nouvelle permet d'améliorer la robustesse des algorithmes.
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Wang, Jing. "Sub-Riemannian heat kernels on model spaces and curvature-dimension inequalities on contact manifolds." Thesis, Purdue University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3636683.
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This dissertation contains two research directions. In the first direction, we deduce explicit expressions of the subelliptic heat kernels on three sub-Riemannian model spaces: the Cauchy-Riemann sphere, the anti-de Sitter space and the Quaternionic sphere. From these explicit subelliptic heat kernels we then derive several by products: the Green function of the conformal sub-Laplacian, the small-time estimates of the subel- liptic heat kernels, and the sub-Riemannian distance. The key point is to work in cylindrical coordinates that reflect the symmetries coming from the Hopf fibration of these model spaces. In the second direction we study the extension of the Baudoin-Garofalo type curvature dimension inequality from the sub-Riemannian transversal symmetric setting to any contact manifold. In particular, the Sasakian condition is no longer assumed which leads to the appearance of new strongly non-linear term in the curvature dimension inequality. This new curvature dimension condition is then used to study several interesting aspects in geometry and analysis: The stochastic completeness of the heat semigroup, geometric conditions ensuring the compactness of the underlying manifold (Bonnet-Myers type results), gradient bounds for the heat semigroup, and spectral gap estimates for the sub-Laplacian.
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Kudawoo, Ayaovi Dzifa. "Problèmes industriels de grande dimension en mécanique numérique du contact : performance, fiabilité et robustesse." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4771/document.
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Ce travail de thèse concerne la mécanique numérique du contact entre solides déformables. Il s'agit de contribuer à l'amélioration de la performance, de la fiabilité et de la robustesse des algorithmes et des modèles numériques utilisés dans les codes éléments finis en particulier Code_Aster qui est un code libre développé par Électricité De France (EDF) pour ses besoins en ingénierie. L'objectif final est de traiter les problèmes industriels de grande dimension avec un temps de calcul optimisé. Pour parvenir à ces objectifs, les algorithmes et formulations doivent prendre en compte les difficultés liées à la mécanique non régulière à cause des lois de Signorini-Coulomb ainsi que la gestion des non linéarités dûes aux grandes déformations et aux comportements des matériaux étudiés.Le premier axe de ce travail est dédié à une meilleure compréhension de la formulation dite de « Lagrangien stabilisé » initialement implémentée dans le code. Il a été démontré l'équivalence entre cette formulation et la formulation bien connue de « Lagrangien augmenté ». Les caractéristiques mathématiques liées aux opérateurs discrets ont été précisées et une écriture énergétique globale a été trouvéeThis work deals with computational contact mechanics between deformable solids. The aim of this work is to improve the performance, the reliability and the robustness of the algorithms and numerical models set in Code_Aster which is finite element code developped by Électricité De France (EDF) for its engineering needs. The proposed algorithms are used to solve high dimensional industrial problems in order to optimize the computational running times. Several solutions techniques are available in the field of computational contact mechanics but they must take into account the difficulties coming from non-smooth aspects due to Signorini-Coulomb laws coupled to large deformations of bodies and material non linearities. Firstly the augmented Lagrangian formulation so-called « stabilized Lagrangian » is introduced. Successively, the mathematical properties of the discrete operators are highlighted and furthermore a novel energetic function is presented. Secondly the kinematical condition with regard to the normal unknowns are reinforced through unconstrained optimization techniques which result to a novel formulation which is so-called « non standard augmented Lagrangian formulation ». Three types of strategies are implemented in the code. The generalized Newton method is developped : it is a method in which all the non linearities are solved in one loop of iterations. The partial Newton method is an hybrid technique between the generalized Newton one and a fixed point method
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Cartier, Sébastien. "Surfaces des espaces homogènes de dimension 3." Phd thesis, Université Paris-Est, 2011. http://tel.archives-ouvertes.fr/tel-00672332.
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Ce mémoire porte sur l'étude des surfaces minimales et de courbure moyenne constante dans les espaces homogènes de dimension 3. Nous établissons les formules de Sym-Bobenko pour les surfaces de courbure moyenne constante 1/2 de H^2xR et minimales du groupe de Heisenberg, et donnons des exemples de construction de telles immersions par la méthode DPW. Nous montrons également que des propriétés de symétrie passent aux correspondances de type surfaces sœurs et cousines, ce qui entraîne l'existence de graphes entiers de courbure moyenne constante 1/2 à bout vertical dans H^2xR qui ne sont pas de révolution. Nous reprenons ensuite l'étude des bouts verticaux d'immersions de courbure moyenne constante 1/2 dans H^2xR. Nous munissons une famille de graphes entiers d'une structure de variété lisse et en déduisons un analogue pour H^2xR d'un théorème de A. E. Treibergs pour l'espace de Minkowski. Nous nous intéressons également aux déformations des anneaux de révolution. Une conséquence directe est l'existence d'anneaux immergés qui ne sont pas de révolution. Nous construisons notamment des anneaux dont les bouts n'ont pas le même axe. Enfin, nous décrivons les invariants de Nœther correspondant aux isométries des espaces homogènes pour les surfaces minimales et de courbure moyenne constante. Nous utilisons le formalisme de la géométrie de contact qui permet l'écriture de formules explicites en toute généralité, et nous étudions l'évolution des formes de Nœther sous l'action des isométries des espaces homogènes. Nous calculons ces invariants dans le cas des anneaux déformés de H^2xR, et dans celui des anneaux horizontaux du groupe de Heisenberg
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Paulin, Christophe. "Etude de l'endommagement du contact multicouche aube/disque sous chargement de fretting : impact des sollicitations variables et de la dimension du contact." Ecully, Ecole centrale de Lyon, 2006. http://www.theses.fr/2006ECDL0001.
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Dans le contexte des assemblages mécaniques, et plus particulièrement pour le contact en queue d'aronde alvéolé aube/disque de turbine, la combinaison d'un chargement normal (force centrifuge) et tangentiel (vibrations) se traduit par des sollicitations de fretting dégradant ainsi le bon fonctionnement de la liaison. Du fait d'une problématique industrielle spécifique Snecma utilise, sur une des deux pièces en Ti-6AI-4V, un revêtement mou et rugueux à base de Cu-Ni-In sur lequel est déposé un film de lubrifiant solide polymérisé à base de MoS2. Le but de cette recherche est alors de comprendre et de formaliser les phénomènes d'usure des différents matériaux en contact pour des conditions variables de sollicitations ainsi que d'en évaluer l' effet de la dimension du contact. Premièrement， pour le couple MoS2/lTi-6AI-4V, nous proposons une cartographie de l'endommagement de ce contact, puis, à partir d'un comportement élasto-plastique, l’établissement de la courbe maîtresse de la durée de vie du dépôt. On montre la stabilité de cette approche quelle que soit la dimension du contact et la géométrie de l'indenteur toutefois celle-ci reste sensible au chargement local appliqué au contact ce qui se traduit par la présence d'un régime d'usure sévère. Concernant l’ usure des matériaux métalliques (Cu-Ni-In et Ti-6AI-4V) un concept spécifique de cinétique d'usure qui prend en compte les phénomènes d'adhésion à l’interface de frottement est introduit. Cette propriété est alors validée pour différentes configurations de contact ainsi que pour des sollicitations variables de glissement. Enfin, la validation d'un modèle éléments finis de l'usure par modification de la surface de contact, qui montre une bonne corrélation avec les tests expérimentaux, permet d'ouvrir la voie à la prédiction de l’endommagement du contact completIn mechanical assemblies and especially for the aeronautical blade on disk contact, the combination between a normal load (centrifugal force) and a tangential load (vibrations) involves fretting solicitations. Resulting contact damages modify contacting surfaces and hinder the good working of the joint. Thus, from this specific industrial problem Snecma is performing a double coating process on one of the two Ti-6Al-4V parts. Lt consists of a soft and rough plasma sprayed layer (Cu-Ni-In) and a polymer bonded MoS2 solid lubricant. The aim of this research is to describe and formalize wear phenomena for variable amplitude conditions as well as the impact of the contact size for each contacting material. Firstly, for the MoS2/lTi-6Al-4V contact, we propose a map of the contact damages encountered ,then, from an elasto-plastic description of the materials we formalize the lifetime master curve. However, this technique reveals that for overcharged contacts the wear regime becomes severe. Then, concerning the wear behaviour of metallic materials, we propose wear kinetics which can take into account adhesion phenomena. This property has been validated for variable amplitude configurations as well as for different contact size and reveals a rather good stability. Finally, the development of an original finite element model of wear, which shows a very good correlation with experimental tests, encourages the way to formalize the global and successive damage of the entire contact
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Roux, Guillaume. "Un cas particulier de la conjecture de Weinstein en grande dimension." Thesis, Nantes, 2017. http://www.theses.fr/2017NANT4116.
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Cette thèse étudie la conjecture de Weinstein dans le cas de certaines variétés de contact de dimension supérieure ou égale à 5. Cette conjecture, qui affirme que tout champ de Reeb sur une variété close orientée possède une trajectoire périodique, a été démontrée par Taubes pour toute variété de dimension 3. Dans ce texte, on en présente une preuve pour les variétés de contact portées par un livre ouvert dont la page est obtenue, à partir d’un certain domaine de Weinstein, en attachant une anse le long d’une sphère legendrienne lâche et homologiquement triviale. Dans une première partie, on examine la situation dans la page. L’attachement d’une anse correspond à effectuer une chirurgie de contact sur le bord, ce qui provoque l’apparition d’une petite orbite de Reeb pour une forme de contact particulière. On s’intéresse alors aux propriétés d’une famille de plans holomorphes asymptotes à cette orbite. Dans une deuxième partie, on prouve que les pages du livre ouvert se relèvent en un feuilletage de la symplectisation par des hyperplans holomorphes, relativement à une structure hamiltonienne stable adaptée. On montre ensuite que cette dernière se déforme en une structure de contact portée par le livre ouvert. Cela permet d’obtenir une description des plans holomorphes au voisinage d’une page donnée, puis de montrer que ces plans se brisent le long d’une orbite de Reeb contractileWe study the Weinstein conjecture for some high dimensional contact manifolds. This conjecture asserts that every Reeb vector field on a closed oriented manifold has a closed orbit, and was proved by Taubes for every three manifold. We show that this statement holds for contact manifolds supported by an open book decomposition, when the page is obtained from a Weinstein domain by attaching a Weinstein handle along a loose, Legendrian, homologically trivial sphere. Attaching such a handle performs a contact surgery on the boundary of the domain, which leads to the creation of a small Reeb orbit for some particular contact form. In a first part, we study the properties of a family of holomorphic planes asymptotic to this orbit. In a second part, we show that the open book decomposition gives rise to a foliation of the symplectisation by holomorphic hypersurfaces, with respect to a suitable stable Hamiltonian structure. The latter can be perturbed into a contact structure supported by the open book decomposition. It allows us to describe a family of holomorphic planes near a given page, thus showing that these planes break along a contractible Reeb orbit
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Raj, Vishnu Heymann Harald. "Assessment of the Apparent Contact Dimension and co-variates in non-treated and orthodontically treated dentitions." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1621.
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Thesis (M.S.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Sep. 16, 2008). "... in partial fulfillment of the requirements for the degree of Master of Sciences in the School Of Dentistry." Discipline: Dentistry; Department/School: Dentistry.
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Guyard, Thomas. "Sur le calcul d'invariants et l'engendrement des noeuds transverses dans les variétés de contact de dimension trois." Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=fcabf9b0-e4c5-4a8a-855c-0a9927814313.
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Le sujet de cette thèse est l’étude et le calcul d’invariants classiques et avancés pour les noeuds transverses dans les variétés de contact de dimension trois. Dans une classe d’isotopie lisse de noeuds, on peut construire une infinité de classes d’isotopie legendrienne de noeuds différentes. Colin, Giroux et Honda ont cependant montré que dans la sphère de contact standard de dimension trois, si on fixe la classe d’isotopie lisse et l’invariant de Thurston-Bennequin, ces classes d’isotopie legendrienne sont alors en nombre fini. On étudie dans cette thèse l’équivalent transverse de ce résultat. Dans un premier temps, on montre que la conjecture de finitude transverse se ramène à la finitude des noeuds legendriens non déstabilisables par l’utilisation de translations legendriennes/transverses. Dans un deuxième temps, on démontre que dans une classe d’isotopie lisse de noeuds, on peut obtenir toutes les classes d’isotopies legendriennes de noeuds non déstabilisables, à partir d’un nombre fini d’entre eux et de modifications de Lutz sur un nombre fini de tores. Dans des cas modèles, on fait le lien entre modification de Lutz et présence de rocade. Dans une dernière partie, on étudie l’homologie de contact cylindrique d’un noeud transverse que l’on aura placé dans la reliure d’un livre ouvert avec une monodromie pseudo-Anosov. On prouve alors que pour un coefficient de twist de Dehn fractionnaire suffisamment grand, le taux de croissance de cette homologie est exponentielWe study the properties of classical and advanced invariants for transverse knots in three-dimensional contact manifolds. In a given isotopy class, we can construct infinitely many different Legendrian knots. Colin, Giroux and Honda have proved however that, in the standard contact three-dimensional sphere, if we fix the Turston-Bennequin-invariant and the knot isotopy class, the Legendrian knots are finite. We investigate a transverse version of this result. In a first part, we show that the transverse finiteness conjecture can be reduced by push-off to the study of the finiteness of Legendrian knots which can’t be destabilized. In a second part, we prove that all the Legendrian knot classes in a knot isotopy class can be obtained from a finite set of Legendrien knots with Lutz modifications on a finite number of torus. Then we explain how this generation result can be used to build a bypass in specific simple cases. In the last part, we study the cylindrical contact homology of a transverse knot by putting it in the binding of an open book decomposition with pseudo-Anosov monodromy. Then we prove that in case where the fractional Dehn twist coefficient is large enough, this contact homology has exponential growth
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Schwägerl, Christian. "Language contact and displays of social identity : the communicative and ideological dimension of code-mixing in a business setting /." Tübingen : Narr, 2010. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=018862297&line_number=0002&func_code=DB_RECORDS&service_type=MEDIA.
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Schwägerl, Christian. "Language contact and displays of social identity the communicative and ideological dimension of code-mixing in a business setting." Tübingen Narr, 2008. http://d-nb.info/1000446514/04.
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Decamp, Jean. "Symétries et corrélations dans les gaz quantiques fortement interagissants à une dimension." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4060/document.
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L’objectif principal de cette thèse est l’étude théorique de mélanges quantiques fortement interagissants à une dimension et soumis à un potentiel externe harmonique. De tels systèmes fortement corrélés peuvent être réalisés et testés dans des expériences d’atomes ultrafroids. Leurs propriétés de symétrie par permutation non triviales sont étudiées, ainsi que leurs effets sur les corrélations. Exploitant une solution exacte pour des interactions fortes, nous extrayons des propriétés générales des corrélations encodées dans la matrice densité à un corps et dans les distributions des impulsions associées, dans les mélanges fermioniques et de Bose-Fermi. En particulier, nous obtenons des résultats substantiels sur le comportement à courtes distances, et donc les queues à haute impulsions, qui suivent des lois en k^−4 typiques. Les poids de ces queues, dénotés contacts de Tan, sont liés à de nombreuses propriétés thermodynamiques des systèmes telles que les corrélations à deux corps, la dérivée de l’énergie par rapport à la longueur de diffusion unidimensionnelle, ou le facteur de structure statique. Nous montrons que ces contacts universels de Tan permettent également de caractériser la symétrie spatiale des systèmes, et constituent donc une connexion profonde entre les corrélations et les symétries. En outre, la symétrie d’échange est extraite en utilisant une méthode de théorie des groupes, à savoir la méthode de la somme des classes (class-sum method en anglais), qui provient à l’origine de la physique nucléaire. De plus, nous montrons que ces systèmes suivent une version généralisée du fameux théorème de Lieb-Mattis. Souhaitant rendre nos résultats aussi pertinents expérimentalement que possible, nous dérivons des lois d’échelle pour le contact de Tan en fonction de l’interaction, de la température et du confinement transverse. Ces lois présentent des effets intéressants liés aux fortes corrélations et à la dimensionnalitéThe main focus of this thesis is the theoretical study of strongly interacting quantum mixtures confined in one dimension and subjected to a harmonic external potential. Such strongly correlated systems can be realized and tested in ultracold atoms experiments. Their non-trivial permutational symmetry properties are investigated, as well as their interplay with correlations. Exploiting an exact solution at strong interactions, we extract general correlation properties encoded in the one-body density matrix and in the associated momentum distributions, in fermionic and Bose-Fermi mixtures. In particular, we obtain substantial results about the short-range behavior, and therefore the high-momentum tails, which display typical k^−4 laws. The weights of these tails, denoted as Tan’s contacts, are related to numerous thermodynamic properties of the systems such as the two-body correlations, the derivative of the energy with respect to the one-dimensional scattering length, or the static structure factor. We show that these universal Tan’s contacts also allow to characterize the spatial symmetry of the systems, and therefore is a deep connection between correlations and symmetries. Besides, the exchange symmetry is extracted using a group theory method, namely the class-sum method, which comes originally from nuclear physics. Moreover, we show that these systems follow a generalized version of the famous Lieb-Mattistheorem. Wishing to make our results as experimentally relevant as possible, we derive scaling laws for Tan’s contact as a function of the interaction, temperature and transverse confinement. These laws. Display displadisplay display interesting effects related to strong correlations and dimensionality
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DO, CARMO SÁ AZEVEDO LEMOS MARGARIDA. "O Design de embalagem como síntese formal e expressiva do conteúdo." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/61438.
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[EN] Packaging is a permanent presence and takes a significant expression in daily life, it contains, protects, informs and gives character to the products, establishing an inseparable relationship between content and container. This research focused on formal, material and communicative packaging aspects of liquid food products, performs a mapping of the issues related to the interrelation of practical functions (performance for the user), aesthetic (configuration and interaction with the user) and symbolic (significance to the user) from the liquid food packages, having as confluence point the relationship content/ product container in the set of interactions/ user/ environment.
Seen as an interface between the product and the user, the packaging of liquid food products, occupies an essential place in our society, allowing an uncountable number of products to reach the hands of those who need them, intact and in perfect condition. The package preserves the physical and temporal natural products, covering them and giving them shape, becoming a product skin like the skin of the fruit or human skin, prolonging their existence, with direct health benefits and well being of the populations.
This thesis has as study object the packaging of liquid food products and how its shape expresses its identity, the concept and function of the product it contains and conforms. This research resorted to analytical studies, based on the reflections of Flusser and Lipovetsky, around the man and his relationship to the object and conducted the identification and recognition of archetypal packaging in the universe of reference products (milk, juice, water and hybrid drinks), as well as the morphological and qualitative comparative analysis of liquid food packaging in different materials (glass, multilayer cardboard, metal, plastic), having as a study focus the inseparable relationship between the content and the container.
This study resulted in the achievement of Tetra Con)forma project goal so that provided the constructive possibilities of the multilayer material for forming a packagings for hybrid liquid drinks, emphasizing the concepts of nomadism (portability), customization (composition) and theatricality (convertibility), wherein the shape is expressed by the structural dimension portability, in the communicative by the composition and in the symbolic by convertibility.[ES] El envase es una presencia permanente y asume una expresión significativa en lo cotidiano, al contener, proteger, informar y conferir carácter a los productos estableciendo una relación indisociable entre el contenido y el contenedor. Esta investigación centrada en los aspectos formales, materiales y comunicativos de los envases de productos alimenticios líquidos, efectúa un mapeado de las cuestiones relacionadas con la interrelación de las funciones prácticas (desempeño para el usuario), estéticas (configuración e interacción con el usuario) y simbólicas (significado para el usuario) de los envases de productos líquidos alimenticios teniendo como punto de convergencia la relación contenido/ contenedor en el conjunto de las interacciones producto/ usuario/ medio. Concebida como interfaz entre el producto y el usuario, el envase de productos líquidos alimentícios ocupa un lugar esencial en nuestra sociedad, permitiendo que un sin número de productos llegue a manos de aquellos que los necesitan, intactos y perfectas condiciones de uso. El envase preserva la integridad física y temporal de los productos naturales, recubriéndolos y dándoles forma, transformándose en una piel del producto a semejanza de la piel de la fruta o de la piel humana, prolongando su existencia, con beneficios directos para la salud y bienestar de la población. La presente tesis tiene por objeto de estudio el envase de productos líquidos alimentícios y el modo en el que su forma expresa la identidad, el concepto y la función del producto que contiene y conforma. Esta investigación provino de estudios analíticos, fundamentados en las reflexiones de Flusser y Lipovetsky en torno al hombre y a su relación con el objeto y procedió a la identificación y reconocimiento de envases arquetipo en el universo de productos de referencia (leche, zumos, agua y bebidas híbridas), así como el análisis morfológico comparado y cualitativo de los envases de productos líquidos alimentícios en los diferentes materiales (vidrio, cartón multicapa, metal, plástico), teniendo como foco de estudio la relación indisociable entre el contenido y el contenedor. Este estudio culminó con la realización del meta proyecto Tetra Con)forma, que previó las posibilidades constructivas del material multicapa para conformar un volumen con)formador para bebidas líquidas híbridas, enfatizando los conceptos de nomadismo (portabilidad), personalización (composición) y teatralidad (convertibilidad), en que se expresa la forma en la dimensión estructural por la portabilidad, en la comunicativa por la composición y en la simbólica por la convertibilidad.
[CAT] L'envàs és una presència permanent i assumeix una expressió significativa el quotidià, en contenir, protegir, informar i conferir caràcter als productes establint una relació indissociable entre el contingut i el contenidor. Aquesta recerca centrada en els aspectes formals, materials i comunicatius dels envasos de productes alimentosos líquids, efectua una localització de les qüestions relacionades amb la correspondència de les funcions pràctiques (acompliment per a l'usuari), estètiques (configuració i interacció amb l'usuari) i simbòliques (significat per a l'usuari) dels envasos de productes líquids alimentosos tenint com a punt de convergència la relació contingut/ contenidor en el conjunt de les interacciones producte/ usuari/ mitjà. Concebuda com a interfície entre el producte i l'usuari, l'envàs de productes líquids alimentosos ocupa un lloc essencial en la nostra societat, permetent que un sense nombre de productes arriben a les mans d'aquells que els necessiten, intactes i perfectes condicions d'ús. L'envàs preserva la integritat física i temporal dels productes naturals, recobrint-los i donant-los forma, transformant-se en una pell del producte a semblança de la pell de la fruita o de la pell humana, perllongant la seua existència, amb beneficis directes per a la salut i benestar de la població. La present tesi té per objecte d'estudi l'envàs de productes líquids alimentosos i la manera en el qual la seua forma expressa la identitat, el concepte i la funció del producte que conté i conforma. Aquesta recerca va provenir d'estudis analítics, fonamentats en les reflexions de Flusser i Lipovetsky entorn de l'home i a la seua relació amb l'objecte i va procedir a la identificació i reconeixement d'envasos arquetip en l'univers de productes de referència (llet, sucs, aigua i begudes híbrides), així com l'anàlisi morfològica comparada i qualitatiu dels envasos de productes líquids alimentosos en els diferents materials (vidre, cartó multicapa, metall, plàstic), tenint com a focus d'estudi la relació indissociable entre el contingut i el contenidor. Aquest estudi va culminar amb la realització del meta projecte Tetra Amb)forma, que va preveure les possibilitats constructives del material multicapa per a conformar un volum amb)formador per a begudes líquides híbrides, emfatitzant els conceptes de nomadisme (portabilitat), personalització (composició) i teatralitat (convertibilitat), en què s'expressa la forma en la dimensió estructural per la portabilitat, en la comunicativa per la composició i en la simbòlica per la convertibilitat.
Do Carmo Sá Azevedo Lemos, M. (2016). O Design de embalagem como síntese formal e expressiva do conteúdo [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61438
TESIS
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Dathe, Hamidou. "Feuilletages des variétés fibrées et structures de contact." Lorient, 2004. http://www.theses.fr/2004LORIS031.
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Dans cette thèse nous étudions les champs de plans sur les variétés de dimension 3. Nous en considérons deux sortes : ceux qui sont intégrables (feuilletages) et leurs opposés à savoir ceux qui ne sont nulle part intégrables (structures de contact). Dans une première partie nous avons examiné plusieurs phénomènes des feuilletages tendus sur de telles variétés : production d'exemples nouveaux, classification, rigidité. Dans une seconde partie nous avons examiné le problème du passage d'un feuilletage à une structure de contact sous plusieurs façons : perturbations, déformations, déformations linéaires.
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Silva-Concilio, Lais Regiane da. "Avaliação da dimensão vertical de oclusão e superficie de contato em função de diferentes tecnicas de inclusão e polimerização." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290539.
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Orientador: Celia Marisa Rizzatti BarbosaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-06T09:27:11Z (GMT). No. of bitstreams: 1 Silva-Concilio_LaisRegianeda_D.pdf: 1615286 bytes, checksum: 5b5a37d894f9d8d033b5fba17bb3f697 (MD5) Previous issue date: 2006
Resumo: O objetivo deste estudo foi avaliar a influência da técnica de processamento laboratorial na área de contato em máxima intercuspidação e dimensão vertical de oclusão em pares de próteses totais analisadas antes e após processamento laboratorial. Para isto foram confeccionadas 40 pares de próteses, separadas aleatoriamente em 4 grupos de acordo com o método de polimerização e tipo de mufla: GI ¿ polimerizadas em água 73oC / 9 horas em muflas monomaxilares; GII ¿ polimerizadas por energia de microondas 20 min. a 20% de potência e 5 minutos a 60% de potência em muflas monomaxilares; GIII ¿ polimerizadas em água 73oC / 9 horas em muflas bimaxilares; GIV ¿ polimerizadas por energia de microondas 20 min. a 20% de potência e 5 minutos a 60% de potência em muflas bimaxilares. Foi realizada a mensuração da DVO e da Superfície de Contato antes e após o processamento laboratorial. Para a mensuração da DVO foi utilizada uma base plana e rígida na qual encaixava-se o paquímetro digital e o articulador. Foram realizadas 3 mensurações em cada fase e calculadas as médias. Para a avaliação das superfícies de contato foi utilizado o software Qwin 550 (Leica®), que foram mensuradas 3 vezes em cada amostra nos períodos pré e pós processamento, e calculadas as respectivas médias. Os dados obtidos foram submetidos à Análise de Variância e teste de Tukey em nível de 5% de significância. Os resultados demonstraram que todos os grupos apresentaram uma variação percentual positiva para a DVO: GI= 1,92%; GII= 2,92; GIII= 2,27% e GIV= 2,72%, sendo que GI e GII apresentaram diferença estatística entre si (p= 0,083). Os dados da superficie de contato demonstraram que não houve diferença estatística entre os grupos tanto nos modelos superiores como nos inferiores. Com exceção do grupo GII nos modelos superiores, todos os grupos apresentaram diminuição da superfície de contato. Pode-se concluir que: 1) a DVO foi alterada em todos os grupos estudados independentemente do método de polimerização; 2) o grupo GII apresentou menor variação percentual da DVO; 3) o grupo GI apresentou maior variação percentual da DVO; 4) não houve diferença entre os grupos quanto a análise da Superfície de Contato Oclusal
Abstract: The purpose of this study was to evaluate different flasking technics using monomaxillary and bimaxillary flasks by microwave irradiation and water bath, in the occlusal vertical dimension and the area of the occlusive contact, before and after the curing. Forty pairs of complete dentures were distributed into four groups of ten pair each, according to the treatments: GI ¿ cured by water bath 73oC/9h and monomaxillary flasks; GII ¿ cured by microwave irradiation 20 minutes at 20% power and 5 minutes at 60% power and monomaxillary flasks; GIII ¿ cured by water bath 73oC/9h and bimaxillary flasks; GIV¿ cured by microwave irradiation 20 minutes at 20% power and 5 minutes at 60% power and bimaxillary flasks. For the measurement of the occlusal vertical dimension was used the table that the articulator and the digital caliper was positioned correctly, three vertical measurements were made before and after the curing. The area of occlusive contact was measure using the software Qwin 550 (Leica®), each pair of denture was measure three times before and after the curing. Datas were submitted to variance analysis and Tukey¿s test at 5% significance level. These demonstrated that all groups showed positive percent variation for the occlusal vertical dimension: GI= 1.92%; GII= 2.92; GIII= 2.27% e GIV= 2.72%, there were significant statistical differences between GI and GII (p=0.083). There weren¿t statistical differences in the datas of the area of the occlusive contact, in the upper and lower models. Except GII, in the upper models, every groups showed reduction in the area of the occlusive contact. It is concluded that: 1) the occlusal vertical dimension changed in all groups independently of curing method; 2) the group GII showed the lowest percent variation of the occlusal vertical dimension; 3) the group GI showed the highest percent variation of the occlusal vertical dimension; 4) there weren¿t statistical differences between the groups in the area of the occlusive contact; 5) all the groups, except GII, showed decreasing of the area of the occlusive contact after laboratorial processing
Doutorado
Protese Dental
Doutor em Clínica Odontológica
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Moreno, Agustin. "Algebraic Torsion in Higher-Dimensional Contact Manifolds." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19849.
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Wir konstruieren Beispiele von Kontaktmannigfaltigkeiten in jeder ungeraden Dimension, welche endliche nicht-triviale algebraische Torsion (im Sinne von Latschev-Wendl) aufweisen, somit straff sind und keine starke symplektische Füllung haben. Wir beweisen, dass Giroux Torsion
algebraische 1-Torsion in jeder ungeraden Dimension impliziert, womit eine Vermutung von Massot-Niederkrüger-Wendl bewiesen wird. Wir konstruieren unendlich viele nicht diffeomorphe Beispiele von 5-dimensionalen Kontaktmannigfaltigkeiten, welche straff sind, keine starke
symplektische Füllung zulassen und keine Giroux Torsion haben. Wir erhalten Obstruktionen für symplektische Kobordismen, ohne für deren Beweis die SFT Maschinerie zu verwenden. Wir geben eine provisorische Definition eines spinalen offenen Buchs in höherer Dimension an, basierend auf der vom 3-dimensionalen Fall aus Lisi-van Horn Morris-Wendl. In einem Anhang geben wir in gemeinsamer Autorenschaft mit Richard Siefring eine wesentliche Zusammenfassung der Schnitttheorie für punktierte holomorphe Kurven und Hyperflächen an, welche die 3-dimensionalen Resultate von Siefring auf höhere Dimensionen verallgemeinert. Mittels der Schnitttheorie erhalten wir eine Anwendung für holomorphe Blätterungen von Kodimension zwei, die wir benutzen um das Verhalten von holomorphem Kurven in unseren Beispielen einzuschränken.We construct examples in any odd dimension of contact manifolds with finite and non-zero algebraic torsion (in the sense of Latschev-Wendl), which are therefore tight and do not admit strong symplectic fillings. We prove that Giroux torsion implies algebraic 1-torsion in any odd dimension, which proves a conjecture of Massot-Niederkrüger-Wendl. We construct infinitely many non-diffeomorphic examples of 5-dimensional contact manifolds which are tight, admit no strong fillings, and do not have Giroux torsion. We obtain obstruction results for symplectic cobordisms, for which we give a proof not relying on SFT machinery. We give a tentative definition of a higher-dimensional spinal open book decomposition, based on the 3-dimensional one of Lisi-van Horn Morris-Wendl. An appendix written in co-authorship with Richard Siefring gives a basic outline of the intersection theory for punctured holomorphic curves and hypersurfaces, which generalizes his 3-dimensional results to higher dimensions. From the intersection theory we obtain an application to codimension-2 holomorphic foliations, which we use to restrict the behaviour of holomorphic curves in our examples.
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Lepse, James LeVoy. "What to Buy: the Underexplored Dimension of the Smart-buyer Problem." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/50623.
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Using one question of Donald Kettl\'s smart-buyer problem as the basis of investigation, this study empirically examines the relationship between five selected services contract characteristics related to requirements and evaluation ratings of 120 federal information technology investments. The five contract characteristics selected for investigation were: Contract Type, Extent Competed, Performance-Based Acquisition, Integrated Process Team, and Program Manager Qualification. Analysis of these characteristics is relevant because current federal acquisition policy advocates particular contract characteristics as the preferred methods of procurement and others as widely accepted best practices. The five selected contract characteristics were analyzed for over 200 information technology services contracts using two separate statistical tests and four variants of information technology investment ratings as the dependent variable. Empirical evidence failed to reject the null hypothesis that there is no statistically significant correlation between selected service contract characteristics related to contract requirements and investment ratings. This failure of rejection through multiple tests led to the conclusion that service contract requirements are not better defined in cases when they should be based on selected contract characteristics. In order to better inform and understand the quantitative findings, interviews were conducted with over 20 senior acquisition and information technology executives representing 11 different federal departments and industry. None of the senior executives interviewed disputed the null finding and nearly 70 percent of subject matter experts interviewed were unsurprised that the selected service contract characteristics did not correlate with investment ratings.The lack of correlation between selected contract characteristics related to requirements and investment ratings indicates that service contract requirements definition is a significant problem for federal agencies. That conclusion was confirmed by interviews with senior subject matter experts who consistently stated that accurately defining and managing information technology service contract requirements is a genuine challenge facing the federal government today.
Although empirical evidence failed to reject the null hypothesis, subsequent interviews revealed other factors that may have greater bearing on requirements and acquisition program outcomes than the five selected service contract characteristics. They present promising topics that merit further research.
Ph. D.
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Duchemin, David. "Quaternionic geometry in low dimensions." Université Louis Pasteur (Strasbourg) (1971-2008), 2004. https://publication-theses.unistra.fr/public/theses_doctorat/2004/DUCHEMIN_David_2004.pdf.
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L'objet principal de cette th`ese est l''etude des structures de contact quaternioniennes en dimension 7,i. E. De distributions de codimension 3 qui apparaissent comme l'infini conforme de m'etriques asymptotiquement hyperboliques quaternioniennes de dimension 8, c'est-`a-dire de m'etriques dont la courbure `a l'infini est asymptotique `a la courbure de l'espace hyperbolique quaternionien. Je montre dans une premi`ere partie `a l'aide d'une construction twistorielle , j'obtiens une condition dite d'intégrabilité , nécéssaire et suffisante pour qu'une structure de contact quaternionienne soit le bord d'une métrique asymptotiquement hyperbolique et quaternion-k"ahlerienne. Je construit ensuite l'espace des petites d'eformations int'egrables et Sp(1)-invariantes de la structure de contact quaternionienne standard sur la sph`ere. Dans le chapitre suivant, je m'int'eresse aux 4-formes de stabilisateur Sp(2)Sp(1), ferm'ees, et asymptotiques`a la 4-forme de l'espace hyperbolique quaternionien. Enfin, la derni`ere partie est consacr'ee `a l''etude de quelques exemples et en particulier `a la construction par quotient quaternionien d'une famille de structures de contact quaternioniennes int'egrables sur la sphère.
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FERREIRA, KATRI INGRID IKA. "THREE DIMENSIONAL ELASTOPLASTIC CONTACT ANALYSIS BY LARGE STRAINS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1998. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2085@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORUNIVERSIDADE FEDERAL DE RORAIMA
Neste trabalho analisa-se o problema de contato entre dois corpos bidimensionais ou tridimensionais com comportamento elasto-plástico submetidos a grandes deformações através de duas metodologias de solução implementadas. O procedimento de solução numérica inclui o tratamento conjunto das não-linearidades geométricas e físicas como também da não-linearidade das condições de contato baseando- se numa estratégia incremental-iterativa. Na modelagem dos corpos utiliza-se o método dos elementos finitos em conjunto com uma formulação Lagrangeana Atualizada e relações constitutivas para grandes deformações elasto- plásticas. Os corpos são considerados ambos deformáveis, supondo a superfície de contato sem atrito. Os métodos implementados foram: o método da Penalidade onde as restrições de contato são satisfeitas de forma aproximada através do emprego do parâmetro de penalidade e o método da Programação Linear Complementar que formula um problema de programação matemática para cada configuração de equilíbrio incremental onde as condições de Kuhn-Tucker são resolvidas pelo esquema de pivoteamento de Lemke [43]. Foi realizada uma análise comparativa entre os métodos e também um estudo paramétrico verificando a influência de parâmetros relevantes para o problema. Foi implementado um algoritmo para consideração da geometria de contato onde são supostas condições genéricas de contato: nó-superfície e onde as relações cinemáticas são dadas em termos de uma função diferenciável da distância.Foram utilizados elementos lineares formulados em deslocamentos, hexaédricos de 8 nós e elementos com uma formulação híbrida - Enhanced Assumed Strain - EAS, que possuem, além de oito nós, três parâmetros internos de deformação, com um campo de deformações trilinear completo, minorando os efeitos de -locking- presentes nos elementos lineares formulados em deslocamentos. O emprego desses dois tipos de elementos teve como finalidade comparar as suas performances em problemas de contato.
In this theses the frictionless contact problem between two- dimensional or three-dimensional deformable bodies with elasto-plastic behavior under finite strains is studied. The numeric solution procedure is based on an incremental- iterative strategy and includes the treatment of geometric and physical nonlinearities as well as those which arise from contact conditions. In the model of body the finite element method together with an updated Lagrangian and elasto-plastic constitutive relations for finite strains is used.For the solution of the contact problem two methods were investigated. The methods were the Penalty method, where the contact restritions are imposed in an aproximated manner with the use of a penalty parameter and the Linear Complementarity Programming method,which is based on the formulation of a mathematic programming problem for each configuration of equilibrium where the Kuhn-Tucker omplementarity conditions corresponding to the contact conditions are solved by the Lemke pivoting scheme [43]. A algorithm was implemented for consideration for the contact geometry where generic conditions of contact are assumed and the kinematic relation is expressed through a differentiable gap function.Displacement based elements with linear interpolations - hexahedral 8 node elements were employed for the space discretization. In order to diminish the locking effects present in these elements, a hibrid formulation - Enhanced Assumed Strain - EAS, with three aditional internal parameters of deformation with an complete trilinear deformation field was employed.
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Nyqvist, Jessika. "Three-dimensional analysis of multilayered rough surface contact." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14736.
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Modern tribological coatings often possess a multilayered structure, where the properties of each layer can be chosen to optimise the tribological performance of the coating. Such structure can offer advantages over a single layer coating in terms of improved coating durability and reduced contact friction and wear. The behaviour of such complex contacts cannot be fully analysed with current contact models, especially when real surface roughness is considered. Therefore, there is a need for an improved contact analysis model that is able to predict the contact behaviour and sub-surface stresses for real rough multilayered contacts. The work presented in this thesis provides a complete three-dimensional numerical model for non-conformal multilayered real rough surface contacts, which offers a powerful tool for analysis and optimisation of such coated contacts. The model can be used to predict the contact pressure distribution and deformations as well as sub-surface stress field due to applied normal and tangential loads. The contacting bodies are modelled to have an arbitrary geometry, possessing real rough surfaces thus avoiding any assumptions about asperity distribution or shape. The model is based on linear elastic theory and utilises the influence coefficients approach to solve for contact pressures and deformations in a rough contact. The influence coefficients are obtained by utilizing Fourier transforms to solve the Navier’s generalized equation for displacement and stress fields, for an imposed set of boundary conditions pertinent to a multilayered contact. An iteration scheme is set up to obtain the full distribution of pressure and displacement for a rough contact given the applied normal loading, friction coefficient and material properties. The model is validated by comparing its predictions for a set of carefully chosen cases to those obtained with existing analytical and numerical solutions. Results are presented to illustrate the capabilities of the model and its potential applications. These results illustrate how the contact performance, in terms of surface and sub-surface stress, can be enhanced by carefully selecting the properties of each of the layers in a complex multilayered coating. Such enhancements could lead to improved durability and efficiency of machine components, such as rolling element bearings.
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Elmas, Gokhan. "Open book decompositions in high dimensional contact manifolds." Thesis, Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/54967.
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In this thesis, we study the open book decompositions in high dimensional contact manifolds. We focus on the results about open book decomposition of manifolds and their relationship with contact geometry.
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Abu-Eshy, A. A. "Muslim learners of English in Britain : The cultural dimension." Thesis, University of Exeter, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383096.
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Leahy, John C. "Three-dimensional frictional contact analysis using the Boundary Element Method." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263491.
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Lamboll, Robin Davies. "Two-dimensional modelling of novel back-contact solar cells." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/268518.
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This dissertation computationally and analytically investigates ways to model solar cells when the lateral motion of charge carriers and light are relevant. We focus on back-contact perovskite solar cells, and assessing the experimental technique of scanning photocurrent microscopy as a means to investigate them. Solar cells are three-dimensional objects frequently modelled as being one-dimensional. However, for more complex designs of solar cell or if the cell is only point-illuminated, one-dimensional modelling is insufficient. In the first study, some conditions for reducing the complexity of two-dimensional drift-diffusion simulations are investigated for a back-contact perovskite cell. Analytic expressions for the relationship in both the low extraction velocity and high extraction velocity regimes are demonstrated, and the conditions where these approximations break down are investigated. These findings are then applied a point-excited film with an extended electrode, a problem encountered during scanning photocurrent microscopy. We show the current recorded in this case should decay exponentially with the distance between excitation and electrode, with a decay constant that can be related to device parameters. The characteristic equilibration time for the system to reach this current is demonstrated to increase linearly with distance. Between this gradient and the exponent, information about the diffusion and recombination mechanics can be extracted from a variety of systems. Photon recycling is the process in whereby photogenerated carriers recombine to generate light that is absorbed again within the solar cell. In the second section, we apply the findings of the first section to show that experimental results published elsewhere are best explained by photon recycling in methylammonium lead iodide perovskite back-contact solar cells. However we do not have an established theoretical model for long-ranged lateral optical transport in these solar cells. Three models are developed: a bimolecular model for unscattered, coherent transport; a photon diffusion model for frequently scattered, noncoherent light; and a monomolecular, assisted-diffusion model. The modal nature of coherent optical transport is considered and modifications to previous one-dimensional theories are made. The nature of the photon diffusion model is discussed, as are theoretical shortcomings. All three models are then solved numerically and compared to experimental results. The low-scattering photon diffusion models correspond well to the experiment. The third investigation involves the performance of different architectures of back-contact perovskite cells. These cells potentially offer increased current due to less shadowing by front electrodes. We compare them to each other and to traditional vertical structures. It is found that, in terms of internal transport, the back-contact solar cells give less efficient performance than the vertical design. The best of the back-contact cells investigated is a flat interdigitated design. The increase in efficiency from optical factors would have to exceed 10% for the overall efficiency of back-contact cells to be higher than vertical devices. We also develop a model of photon recycling appropriate for short-ranged, bulk 2D transport and demonstrate that in perovskites, it produces little change in power conversion efficiency (and small changes in short-circuit voltage) when compared with the standard drift-diffusion equations with the second-order recombination constant is adjusted.
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Dormois, Hervé. "Frottement dans les contacts EHD de grandes dimensions, rôle du pivotement." Lyon, INSA, 2008. http://theses.insa-lyon.fr/publication/2008ISAL0091/these.pdf.
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Dans cette thèse, nous nous sommes intéressés au cas particulier des contacts lubrifiés en régime EHD en présence de pivotement avec un grand rayon de contact. Dans le domaine des contacts EHD, l’introduction d’une composante de pivotement a peu été étudiée. Pour mieux comprendre les effets du pivotement sur un contact EHD de grande dimension, un banc d’essais et un modèle numérique ont été conçus. Le banc d’essais a permis de travailler dans des conditions proches de celles que subissent industriellement les contacts, tandis que le modèle numérique a permis de comprendre les conséquences locales du pivotement et de la taille du contact. Les effets observés du pivotement sont une diminution du coefficient de frottement et de l’épaisseur de film et une dissymétrie de cette épaisseur. D’autres effets furent aussi mis en évidence. Grâce à l’implantation d’un système permettant de quantifier la dissipation thermique dans le contact, il s’est avéré que l’augmentation du pivotement s’accompagnait d’une augmentation de la température dans le contact. En comparant les différents résultats expérimentaux et numériques, il s’est avéré que le pivotement modifiait les conditions du contact en introduisant des taux de cisaillement supplémentaires dans la direction du roulement et celle transversale. Ces cisaillements supplémentaires, non constants sur la surface de contact, engendrent une plus grande dissipation thermique dans le contact ainsi qu’une diminution de la viscosité par effet rhéofluidisant, ce qui est à l’origine de la baisse du coefficient de frottement et de la diminution de l’épaisseurThere are lubricated contacts in several mechanical applications. In this thesis, we were interested in the particular case of lubricated contacts in the elastohydrodynamic lubrication (EHL) regime with spin motion and large contact size. This kind of contacts is industrially present in the taper roller bearing, between the end of the roller and the rib. Only few authors worked on the subject of EHL with a spin motion. However, these authors found that the spin leads to a decrease of the film thickness and the friction coefficient. To better understand how the spin modifies the contact conditions, a test rig and a numerical model were built. The test rig allowed us to simulate closely industrial contacts, both in term of spin quantity and contact size, whereas the numerical model enabled us to understand on which contact parameters the spin motion acts. First of all, the main tendencies measured with Tribogyr and the numerical model are the same as those found in the literature. Then other results were produced. Thanks to the large contact size and temperature measurements, we were able to quantify the thermal dissipation relatively to the contact condition. The result is that the thermal dissipation is linked with the level of spin introduced in the contact. Then, the numerical results showed that the film thickness decreases and looses its symmetry when a spin motion is introduced. The comparison of the results obtained with the test rig and the numerical model showed that the spin introduces an additional shear rate in both rolling and transversal direction that modifies the contact conditions. This additional shearing is not constant over the contact surface and generates a higher heat production and a viscosity reduction by shear thinning effect. Both of these effects lead to decrease the friction coefficient and the film thickness
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Hall, R. W. "Two dimensional isoviscous EHL and associated contact problems in linear elasticity." Thesis, University of Leeds, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374172.
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Voiry, Matthieu. "Étude et conception d'un système automatisé de contrôle d'aspect des pièces optiques basé sur des techniques connexionnistes." Thesis, Paris Est, 2008. http://www.theses.fr/2008PEST0077/document.
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Dans différents domaines industriels, la problématique du diagnostic prend une place importante. Ainsi, le contrôle d’aspect des composants optiques est une étape incontournable pour garantir leurs performances opérationnelles. La méthode conventionnelle de contrôle par un opérateur humain souffre de limitations importantes qui deviennent insurmontables pour certaines optiques hautes performances. Dans ce contexte, cette thèse traite de la conception d’un système automatique capable d’assurer le contrôle d’aspect. Premièrement, une étude des capteurs pouvant être mis en oeuvre par ce système est menée. Afin de satisfaire à des contraintes de temps de contrôle, la solution proposée utilise deux capteurs travaillant à des échelles différentes. Un de ces capteurs est basé sur la microscopie Nomarski ; nous présentons ce capteur ainsi qu’un ensemble de méthodes de traitement de l’image qui permettent, à partir des données fournies par celui-ci, de détecter les défauts et de déterminer la rugosité, de manière robuste et répétable. L’élaboration d’un prototype opérationnel, capable de contrôler des pièces optiques de taille limitée valide ces différentes techniques. Par ailleurs, le diagnostic des composants optiques nécessite une phase de classification. En effet, si les défauts permanents sont détectés, il en est de même pour de nombreux « faux » défauts (poussières, traces de nettoyage. . . ). Ce problème complexe est traité par un réseau de neurones artificiels de type MLP tirant partie d’une description invariante des défauts. Cette description, issue de la transformée de Fourier-Mellin est d’une dimension élevée qui peut poser des problèmes liés au « fléau de la dimension ». Afin de limiter ces effets néfastes, différentes techniques de réduction de dimension (Self Organizing Map, Curvilinear Component Analysis et Curvilinear Distance Analysis) sont étudiées. On montre d’une part que les techniques CCA et CDA sont plus performantes que SOM en termes de qualité de projection, et d’autre part qu’elles permettent d’utiliser des classifieurs de taille plus modeste, à performances égales. Enfin, un réseau de neurones modulaire utilisant des modèles locaux est proposé. Nous développons une nouvelle approche de décomposition des problèmes de classification, fondée sur le concept de dimension intrinsèque. Les groupes de données de dimensionnalité homogène obtenus ont un sens physique et permettent de réduire considérablement la phase d’apprentissage du classifieur tout en améliorant ses performances en généralisationIn various industrial fields, the problem of diagnosis is of great interest. For example, the check of surface imperfections on an optical device is necessary to guarantee its operational performances. The conventional control method, based on human expert visual inspection, suffers from limitations, which become critical for some high-performances components. In this context, this thesis deals with the design of an automatic system, able to carry out the diagnosis of appearance flaws. To fulfil the time constraints, the suggested solution uses two sensors working on different scales. We present one of them based on Normarski microscopy, and the image processing methods which allow, starting from issued data, to detect the defects and to determine roughness in a reliable way. The development of an operational prototype, able to check small optical components, validates the proposed techniques. The final diagnosis also requires a classification phase. Indeed, if the permanent defects are detected, many “false” defects (dust, cleaning marks. . . ) are emphasized as well. This complex problem is solved by a MLP Artificial Neural Network using an invariant description of the defects. This representation, resulting from the Fourier-Mellin transform, is a high dimensional vector, what implies some problems linked to the “curse of dimensionality”. In order to limit these harmful effects, various dimensionality reduction techniques (Self Organizing Map, Curvilinear Component Analysis and Curvilinear Distance Analysis) are investigated. On one hand we show that CCA and CDA are more powerful than SOM in terms of projection quality. On the other hand, these methods allow using more simple classifiers with equal performances. Finally, a modular neural network, which exploits local models, is developed. We proposed a new classification problems decomposition scheme, based on the intrinsic dimension concept. The obtained data clusters of homogeneous dimensionality have a physical meaning and permit to reduce significantly the training phase of the classifier, while improving its generalization performances
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Verma, Navni. "Development and Demonstration of Thermal Contact Conductance (TCC) Models for Contact Between Metallic Surfaces." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555452213472626.
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Niederkrüger, Klaus. "On fillability of contact manifolds." Habilitation à diriger des recherches, Université Paul Sabatier - Toulouse III, 2013. http://tel.archives-ouvertes.fr/tel-00922320.
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The aim of this text is to give an accessible overview to some recent results concerning contact manifolds and their symplectic fillings. In particular, we work out the weakest compatibility conditions between a symplectic manifold and a contact structure on its boundary to still be able to obtain a sensible theory (Chapter II), furthermore we prove two results (Theorem A and B in Section I.4) that show how certain submanifolds inside a contact manifold obstruct the existence of a symplectic filling or influence its topology. We conclude by giving several constructions of contact manifolds that for different reasons do not admit a symplectic filling.
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Chan, Jennifer Kim Lian. "Guest satisfaction dimensions in the ecolodge context." Thesis, University of Strathclyde, 2005. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21594.
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This thesis explores guest satisfaction dimensions from the consumer perspective in the ecolodge context and asks to what extent guest satisfaction can be explained by using Herzberg's Motivator and Hygiene Factor Theory. Guest satisfaction dimensions are explored from the experiential perspective and the behavioural approach to refocus and replace the expectancy disconfirmation paradigm and SERVQUAL model that are primarily based on cognitive aspects and ignores the experiential factors. The present research recognises that in the service experience context the experiential and perceptions factors contribute significantly to guest satisfaction (Otto and Ritchie, 1996). The present research recognises the complexity and controversy of the measurement and definition of satisfaction as well as its constructs due to lack of generally acceptable definition of satisfaction. The complexity of guest satisfaction can be approached from an alternative perspective by extending Herzberg's theory developed for job satisfaction. This theory is contended to be better able to address human satisfaction more adequately compared to expectancy disconfirmation and service quality theory as both of these theoretical underpinning are driven by product and services. It has demonstrated both theoretical and operations limitations of expectancy disconfirmation and service quality theories in measuring consumer satisfaction in the service experience context. To overcome the methodological limitation of Herzberg's approach, the present research incorporates a multi research technique of participation observation and Profile Accumulation Techniques (PAT) for data collection. PAT is adapted from its original version developed by Johns and Lee-Ross (1995). These research techniques supplement and complement the strengths and weaknesses and to achieve consistency and reliability. An exploratory qualitative inductive approach enables the collection of "authentic" data that capture guests' voices. This offers a satisfactory methodological framework and a holistic, reliable and valid approach. The research reveals that guests interact with physical and human dimensions, involvement, and participation in leisure activities that are the main elements termed as satisfaction dimensions or satisfiers. The physical facilities, amenities and maintenance and operations standard are regarded as main elements of dissatisfaction dimensions or dissatisfiers. Guests' satisfaction is measured from both the cognitive and affective responses derived from two different sets of constructs. These satisfaction/dissatisfaction dimensions emerge from two different opposite motivational forces, as two different continua. At one extreme, satisfiers are dimensions related to the personal experiential aspects that derive from the ranges of natural environment and attractions, physical sites and participation in leisure activities that are sourced from the external ecolodge environment. These are intangible elements that are also uncontrollable by the ecolodge operators. At the other extreme, dissatisfiers are dimensions related to the performance and availability of facilities, amenities and maintenance of the ecolodge context. These are regarded as tangible and controllable elements. This indicates that guest satisfction with ecolodges is a two-dimensional measurement. Thus, Herzberg's theory is capable of exploring and explaining guest satisfaction dimensions, and these are perceived as two distinct constructs to represent service quality dimensions in a more meaningful way. This suggests that guest satisfaction can be theorised by job satisfaction theory and both contribute to human life satisfaction and the principle of human dual factors using Herzberg's theory. However, one must also note that these dimensions suggest that satisfiers and dissatisfiers may not be universal as they are subject to the nature of the service context and the type of activities provided.
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Brown, Thomas Alexander Gordon. "Embedded contact knot homology and a surgery formula." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/278521.
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Embedded contact homology is an invariant of closed oriented contact 3-manifolds first defined by Hutchings, and is isomorphic to both Heegard Floer homology (by the work of Colin, Ghiggini and Honda) and Seiberg-Witten Floer cohomology (by the work of Taubes). The embedded contact chain complex is defined by counting closed orbits of the Reeb vector field and certain pseudoholomorphic curves in the symplectization of the manifold. As part of their proof that ECH=HF, Colin, Ghiggini and Honda showed that if the contact form is suitably adapted to an open book decomposition of the manifold, then embedded contact homology can be computed by considering only orbits and differentials in the complement of the binding of the open book; this fact was then in turn used to define a knot version of embedded contact homology, denoted ECK, where the (null-homologous) knot in question is given by the binding. In this thesis we start by generalizing these results to the case of rational open book decompositions, allowing us to define ECK for rationally null-homologous knots. In its most general form this is a bi-filtered chain complex whose homology yields ECH of the closed manifold. There is also a hat version of ECK in this situation which is equipped with an Alexander grading equivalent to that in the Heegaard Floer setting, categorifies the Alexander polynomial, and is conjecturally isomorphic to the hat version of knot Floer homology. The main result of this thesis is a large negative $n$-surgery formula for ECK. Namely, we start with an (integral) open book decomposition of a manifold with binding $K$ and compute, for all $n$ greater than or equal to twice the genus of $K$, ECK of the knot $K(-n)$ obtained by performing ($-n$)-surgery on $K$. This formula agrees with Hedden's large $n$-surgery formula for HFK, providing supporting evidence towards the conjectured equivalence between the two theories. Along we the way, we also prove that ECK is, in many cases, independent of the choices made to define it, namely the almost complex structure on the symplectization and the homotopy type of the contact form. We also prove that, in the case of integral open book decompositions, the hat version of ECK is supported in Alexander gradings less than or equal to twice the genus of the knot.
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Simmons, Bethany Marie. "Nonlinear contact and indenter problems by one-dimensional integral equations." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1433467.
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Chaudhary, Anil Bhaskar. "A solution method for two- and three-dimensional contact problems." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15272.
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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Includes bibliographical references.
by Anil Bhaskar Chaudary.
Sc.D.
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Asplund, Johan. "Contact Homology of Legendrian Knots in Five-Dimensional Circle Bundles." Thesis, Uppsala universitet, Algebra och geometri, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-296880.
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Havemann, Yolandi. "An exploration of the psychological contract between client and consultant." Diss., University of Pretoria, 2011. http://hdl.handle.net/2263/24710.
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Since the late 20th Century, the consulting industry has grown significantly. Today, consulting is a widespread, one-size-fits-all term that includes virtually any form of advice-giving in a business setting. Irrespective of the industry, there is a large market and high demand for consulting. Knowing how to engage clients and ensuring successful consulting has never been more critical for consultancies looking to capitalise on scarce client demand. The purpose of this research study was to gain a collective understanding of those aspects that constitute successful consulting, focusing on the implicit dimensions that influence client-consultant engagement. In this regard, the research study aimed to add value by presenting a new perspective on, and extend understanding of the implicit dimensions influencing the client-consultant relationship by focusing on both clients and consultants though the unique lens of the Psychological Contract. This exploration of the Psychological Contract between client and consultant was conducted through the interpretivist paradigm, or to be more specific, a social constructivist approach. This approach allowed the researcher to explore the Psychological Contract between client and consultant through the constructed meanings that both clients and consultants attach to their experience of the client-consultant relationship, and enabled the researcher to explore their perceptions and interpretations of the dimensions that influenced that relationship. The researcher furthermore applied a qualitative research design and constructivist grounded theory method to explore the subjective meanings of clients and consultants, and to discover their reality. This design and method generated rich, in-depth data and understanding of the participants’ beliefs, perceptions, and subjective experiences to develop a comprehensive framework of the Psychological Contract between client and consultant.Dissertation (MCom)--University of Pretoria, 2011.
Human Resource Management
unrestricted
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Ford, George T. IV. "Media Influences and Student Attitudes Toward Law Enforcement Figures Within Northeast Tennessee." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etd/1167.
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The purpose of this study is to analyze student attitudes toward various law enforcement figures and to obtain a better understanding of public relations, police effectiveness, and media influences in Northeastern Tennessee. This literature review provided a preliminary analysis of related works to advance the accuracy in conducting and examining future studies. The fields that deserve the most analysis are the underlying dimensions associated with public attitudes about police effectiveness, the media’s impact on public attitudes toward police, and the individual, external, and contextual variables that influence public attitudes toward police.
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Hack, Roy Stuart. "The boundary element method applied to practical two-dimensional frictional contact problems." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287189.
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Krtička, Jakub. "Statické řešení bazénu v novostavbě horského hotelu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226921.
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The static solution at the new building mountain hotel The thesis deals with design and static calculation of pool tank, which is supported by columns and walls. Pool tank is designed as swimming pool with plan dimension 25 x 10 meters and with changing depth from 1,2 to 1,8 meters. The support of pool tank is in distance 5,02 x 5,05 meters. The adjacent ceiling is placed on the walls of tank and separates pool and technical areas. The calculations of inner forces were realized by computational programm for two models a) without decline of supports, and model b) with decline of supports. The design of reinforcement is performed for the bottom and walls of tank. The deformations modeling was made at the other part of the thesis. All results were evaluated and summarized at the conclusion. Drawing documentation was made subsequently.
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Sreekumar, Vishnu. "The Geometry and Dynamics of Context." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1355417852.
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Gokay, Kemal. "Contact Mechanics Of Graded Materials With Two Dimensional Material Property Variations." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606527/index.pdf.
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ABSTRACT
CONTACT MECHANICS OF GRADED MATERIALS WITH TWODIMENSIONAL
MATERIAL PROPERTY VARIATIONS
Gökay, Kemal M.S., Department of Mechanical Engineering Supervisor: Asst. Prof. Dr. Serkan Dag September 2005, 62 pages Ceramic layers used as protective coatings in tribological applications are known to be prone to cracking and debonding due to their brittle nature. Recent experiments with functionally graded ceramics however show that these material systems are particularly useful in enhancing the resistance of a surface to tribological damage. This improved behavior is attributed to the influence of the material property gradation on the stress distribution that develops at the contacting surfaces. The main interest in the present study is in the contact mechanics of a functionally graded surface with a two &ndash
dimensional spatial variation in the modulus of elasticity. Poisson&rsquo
s ratio is assumed to be constant due to its insignificant effect on the contact stress distribution [30]. In the formulation of the problem it is assumed that the functionally graded surface is in frictional sliding contact with a rigid flat stamp. Using elasticity theory and semi-infinite plane approximation for the graded medium, the problem is reduced to a singular integral equation of the second kind. Integral equation is solved numerically by expanding the unknown contact stress distribution into a series of Jacobi polynomials and using suitable collocation points. The developed method is validated by providing comparisons to a closed form solution derived for homogeneous materials. Main numerical results consist of the effects of the material nonhomogeneity parameters, coefficient of friction and stamp size and location on the contact stress distribution.
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Nakazawa, Takeshi. "THREE-DIMENSIONAL NON-CONTACT SURFACE PROFILERS FOR SEMICONDUCTOR IC PACKAGE INSPECTION." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/205472.
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The subject of this dissertation is the development of three-dimensional (3D) surface profilers for semiconductor back-end inspection. The value of this study is: 1) to provide a new phase-to-height relationship for Fourier Transform Profilometry (FTP) that is universal as it allows alternate FTP system architectures for a micrometer scale object measurement, and 2) to provide a new method for full field substrate warpage and ball grid array (BGA) coplanarity inspection using machine vision. The desire to increase electronic device performance has resulted in denser and smaller IC packaging. As the dimensions of the devices decrease, the requirements for substrate flatness and surface quality become critical in avoiding device failure. For a high yield production, there is an increasing demand in the requirement for the dimensional verification of height, which requires 3D inspection. Based on the current demands from the semiconductor industry, this dissertation addresses the development of fast in-line surface profilers for large volume IC package inspection. Specifically, this dissertation studies two noncontact surface profilers. The first profiler is based on FTP for measuring the IC package front surface, the silicon die and the epoxy underfill profile. The second profiler is based on stereovision and it is intended for inspecting the BGA coplanarity and the substrate warpage. A geometrical shape based matching algorithm is also developed for finding point correspondences between IC package images. The FTP profiler provides a 1 σRMS error of about 4 μm for an IC package sample in an area of 14 mm x 6.5 mm with a 0.13 second data acquisition time. For evaluating the performance of the stereovision system, the linearity between our system and a confocal microscope is studied by measuring a particular IC sample with an area of 38 mm x 28.5 mm. The correlation coefficient is 0.965 and the 2σdifference in the two methods is 26.9 μm for the warpage measurement. For BGA coplanarity inspection the correlation coefficient is 0.952 and the 2difference is 31.2 μm. Data acquisition takes about 0.2 seconds for full field measurements.
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Medri, Filippo <1978>. "3-Dimensional Protein Reconstruction from Contact Maps: Complexity and Experimental Results." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1812/.
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Saldivia, Berríos Josefina Alejandra. "Efecto de la colocación del plano pivotante posterior, con contacto oclusal sauve, en la posición condilar, según biotipo facial." Tesis, Universidad de Chile, 2010. http://repositorio.uchile.cl/handle/2250/134396.
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Trabajo de Investigación Requisito para optar al Título de Cirujano DentistaAutor no autoriza el acceso a texto completo de su documento
El plano pivotante posterior ha generado controversias a lo largo de los años en relación a su mecanismo de acción. Desde un punto de vista biomecánico, teóricamente, la mandíbula se comporta como una palanca clase III durante el cierre mandibular, donde el vector resultante de las fuerzas de cierre mandibular se encontraría a nivel del primer molar (Guichet N., 1977). Al existir un tope molar, ubicado posteriormente a la resultante de las fuerzas musculares, a nivel del segundo molar, se produciría una palanca de primera clase (Mansour R., 1975), produciéndose un descenso del cóndilo mandibular y con esto una descompresión de los tejidos intra-articulares (Kilpatrick S., 1991; Stiesch-Scholz M., 2005; Klasser G., 2009). En el año 2008, Montini realiza un estudio donde evalúa la posición condilar frente a la colocación de un plano pivotante posterior en apriete máximo voluntario, obteniendo como resultado un descenso condilar en el 88% de los casos, siendo éste mayor en individuos braquifaciales con respecto a dólicofaciales. Este estudio evaluó la posición condilar frente a la colocación de un plano pivotante posterior en contacto oclusal suave, en 32 individuos sanos sin Trastornos Temporomandibulares, agrupados según biotipo facial determinado por el coeficiente VERT. Para evaluar la posición condilar se utilizó la técnica transcraneal oblicua de Schüller modificada por Farrar, individualizada con una técnica submento-vértex. Para el análisis estadístico de la información obtenida se utilizó t Student, ANOVA, chi cuadrado y test de proporciones, considerándose un nivel de significancia de 95% y un p ≤ 0,05. Como resultados se obtuvo un descenso condilar puro o con componente anteroposterior en el 98,44% de los casos, produciéndose un aumento del espacio articular superior de 1,21mm. No se encontraron diferencias estadísticamente significativas al comparar la magnitud de los espacios articulares entre biotipos faciales (p>0,05).
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Zürcher, Thomas Zürcher Thomas. "Hausdorff dimension and regularity of Sobolev functions /." [S.l.] : [s.n.], 2009. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Chimanpure, Amit S. "A Generalized Elastohydrodynamic Lubrication Model for Two-Dimensional Contacts." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595503685282483.
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