International Professional University of Technology in Nagoya Repository
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Study of Magnetoconvection Impact on a Solenoid Coil Cooling by Ferrofluid with a Spectral / Finite Element Method
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Objets passifs pour une entrée multi-points riche
No full textThis thesis investigates a novel input technique for enriching the gesture vocabulary on a multi-touch surface based on fingers' relative location and passive tokens. The first project, TouchTokens, presents a novel technique for interacting with multi-touch surfaces and tokens. The originality is that these tokens are totally passive (no need for any additional electronic components) and their design features notches that guide users' grasp. The purpose of the notches is to indicate a finger spatial configuration (touch pattern) that is specific to the token. When users hold a token and place it on the surface, touching them simultaneously, the system can recognize the resulting touch patterns with a very high level of accuracy (>95%). This approach works on any touch-sensitive surface and makes it possible to easily build low-cost interfaces that combine no-conductive tangibles and gestural input. This technique supports a new multi-touch input that the system can recognize. However, the interaction is limited to the two-state model of touch interaction as the system only knows the tokens' position and cannot detect tokens that are not touched. In the second project of the thesis, we introduce a laser-cut lattice hinge technique for making the tokens flexible. We then develop a new recognizer that analyzes the micro-movements of the fingers while user are holding and deforming those tokens on the surface. We run three experiments to design and calibrate algorithms for discriminating the three following types of manipulations: (1) when a token is left on the surface rather than taken off it (On/Off); (2) when a token has been bent, and (3) when it is squeezed. Our results show that our algorithms can recognize these three manipulations with an accuracy of: On/Off 90.1%, Bent 91.1% and Squeezed 96,9%.The thesis concludes with the presentation of two tools, TouchTokenBuilder and TouchTokenTracker, for facilitating the development of tailor-made tangibles using a simple direct-manipulation interface. TouchTokenBuilder is a software application that assists interface designers in placing notches on arbitrarily-shaped vector contours for creating conflict-free token sets and warning them about potential conflicts. It outputs two files: a vector-graphics description of all tokens in the set and a numerical description of the geometry of each token. TouchTokenTracker is a software library that takes as input the numerical description produced by TouchTokenBuilder, and enables developers to track the tokens' full geometry (location, orientation and shape) throughout their manipulation on the multi-touch surface.L'entrée multi-points offre un canal d'interaction très expressif pour les dispositifs équipés d'une technologie tactile multi-points. Cependant, alors que la taille du canal de communication est, en théorie, très grande, la plupart des systèmes n'en font, en pratique, qu'un usage très limité. Cet état de fait est probablement dû à la difficulté de gérer un grand nombre de gestes multi-points pour deux raisons principales: (1) les limites cognitives et motrices des humains et (2) les difficultés techniques pour l'élaboration de systèmes de reconnaissance robustes. Cette thèse étudie une nouvelle technique d'entrée, TouchTokens, pour enrichir le vocabulaire de gestes multi-points, en se basant sur la position relative des points de contact et des objets (tokens) passifs. Un TouchToken est un "token" passif avec des encoches qui indiquent à l'utilisateur comment l'attraper, et qui est donc associé à une configuration de doigts qui lui est propre. Ainsi, lorsque les utilisateurs tiennent un token tout en étant en contact avec la surface, le système reconnaît le schéma de points de contact correspondant avec une grande robustesse. Nous commençons par présenter le principe avec des tokens rigides de forme basique. L'algorithme de reconnaissance et la conception des tokens sont issus des conclusions d'une étude formative dans laquelle nous avons collecté et analysé des schémas de points de contact lorsque les utilisateurs tiennent des tokens de taille et de forme variable. Cette première étude montre que les utilisateurs ont des stratégies individuelles cohérentes, mais que ces stratégies dépendent de l'utilisateur. Ces conclusions nous ont menés à l'élaboration de tokens avec des encoches afin que les utilisateurs attrapent un même token toujours de la même façon. L'expérience que nous avons menée sur ce nouvel ensemble de tokens démontre que nous pouvons les reconnaître avec un niveau de robustesse supérieur à 95%. Nous discutons les rôles que peuvent jouer les TouchTokens dans les systèmes interactifs, et nous présentons un échantillon d'applications de démonstration. La conception initiale des TouchTokens ne supporte qu'un ensemble d'interactions se limitant au modèle à deux états de l'interaction directe. Dans un second projet, nous décrivons une technique de fabrication avec une découpeuse laser qui permet de faire des tokens flexibles que les utilisateurs peuvent, par exemple, courber ou compresser en plus de les faire glisser sur la surface. Nous augmentons notre reconnaisseur pour analyser les micro-mouvements des doigts pendant la manipulation du token afin de reconnaître ces manipulations. Cette approche basée sur l'analyse des micro-mouvements des doigts nous permet également de discriminer, lorsque l'utilisateur enlève ses doigts de la surface, le cas où il enlève le token de la surface, du cas où le token est resté sur la surface. Nous rapportons sur les expériences que nous avons menées pour déterminer la valeur des paramètres de nos différents reconnaisseurs, et tester leur robustesse. Nous obtenons des taux de reconnaissance supérieurs à 90% sur les données collectées. Nous finissons cette thèse par la présentation de deux outils qui permettent de construire et reconnaître des tokens de forme arbitraire, TouchTokenBuilder and TouchTokenTracker. TouchTokenBuilder est une application logicielle qui permet de placer des encoches sur des contours vectoriels de forme arbitraire, et qui alerte en cas de conflit de reconnaissance entre tokens. TouchTokenBuilder produit deux fichiers en sortie: une description vectorielle des tokens pour leur construction, et une description numérique servant à leur reconnaissance. TouchTokenTracker est une librairie logicielle qui prend cette description numérique en entrée, et qui permet aux développeurs de traquer la géométrie (position, orientation et forme) des tokens au cours de leur manipulation sur la surface
A compositional method to model dependent failure behavior based on PoF models
No full textInternational audienceIn this paper, a new method is developed to model dependent failure behaviors among failure mechanisms. Unlike existing methods, the developed method models the root cause of the dependency explicitly, so that a deterministic model, rather than a probabilistic one, can be established. Three steps comprise the developed method. First, physics-of-failure (PoF) models are utilized to model each failure mechanism. Then, interactions among failure mechanisms are modeled as a combination of three basic relations, competition, superposition and coupling. This is the reason why the method is referred to as " compositional method ". Finally, the PoF models and the interaction model are combined to develop a deterministic model of the dependent failure behaviors. As a demonstration, the method is applied on an actual spool and the developed failure behavior model is validated by a wear test. The result demonstrates that the compositional method is an effective way to model dependent failure behaviors
Ultrafast electron dynamics in twisted graphene by femtosecond photoemission electron microscopy
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Comparison between Ir, Ir 0.85 Rh 0.15 and Ir 0.7 Rh 0.3 thin films as electrodes for surface acoustic waves applications above 800°C in air atmosphere
No full textInternational audience—In this paper, we investigate the suitability of Ir, Ir 0.85 Rh 0.15 and Ir 0.7 Rh 0.3 thin films as electrodes for surface acoustic waves (SAW) applications taking place above 800°C in air atmosphere. As expected, all films oxidize from 800°C in IrO 2 or Ir x Rh 1-x O 2 phase. The electrical properties of the latter remain compatible with the design of SAW devices, with a specific electrical resistance of 151 and 100 µΩ·cm for x = 0.7 and x = 0.85 respectively. Moreover, we observe that the Ir x Rh 1-x O 2 phase is much more stable regarding sublimation effect than the IrO 2 phase, highlighting the interest of alloying Ir with Rh for high-temperature applications. SAW devices based on langasite substrate and Ir 0.85 Rh 0.15 electrodes show a very good stability for at least several days at 800°C in air. In the case of Ir 0.7 Rh 0.3 electrodes, this stability is extended to temperatures up to 900°C
FFT extension for algebraic-group factorization algorithms
No full textInternational audienceIt is well known that the second stage of factoring methods that exploit smoothness of group orders can be implemented efficiently using the fast Fourier transform (FFT). For Pollard's p−1 method [17] this originated with the Mont-gomery and Silverman paper [16], and for the elliptic curve factoring method [12] it was the subject of Peter Montgomery's PhD dissertation [14]. Along with Peter's most recent work on this subject [15], these developments are presented in this chapter
Heat conduction tuning by wave nature of phonons
No full textInternational audienceThe world communicates to our senses of vision, hearing, and touch in the language of waves, because light, sound, and even heat essentially consist of microscopic vibrations of different media. The wave nature of light and sound has been extensively investigated over the past century and is now widely used in modern technology. However, the wave nature of heat has been the subject of mostly theoretical studies because its experimental demonstration, let alone practical use, remains challenging due to its extremely short wavelengths. We show a possibility to use the wave nature of heat for thermal conductivity tuning via spatial short-range order in phononic crystal nanostructures. Our experimental and theoretical results suggest that interference of thermal phonons occurs in strictly periodic nanostructures and slows the propagation of heat. This finding expands the methodology of heat transfer engineering to the wave nature of heat
Security of Networks and Services in an All-Connected World - 11th IFIP WG 6.6 International Conference on Autonomous Infrastructure, Management, and Security (IFIP AIMS 2017)
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Micro-photoluminescence investigation of the doping level in single GaAs crystals epitaxially grown on silicon for multijunction solar cells
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Post-Impact Adaptive Compliance for Humanoid Falls Using Predictive Control of a Reduced Model
No full textInternational audienceWe consider control of a humanoid robot in active compliance just after the impact consecutive to a fall. The goal of this post-impact braking is to absorb undesired linear momentum accumulated during the fall, using a limited supply of time and actuation power. The gist of our method is an optimal distribution of undesired momentum between the robot's hand and foot contact points, followed by the parallel resolution of Linear Model Predictive Control (LMPC) at each contact. This distribution is made possible thanks to \emph{torque-limited friction polytopes}, an extension of friction cones that takes actuation limits into account. Individual LMPC results are finally combined back into a feasible CoM trajectory sent to the robot's whole-body controller. We validate the solution in full-body dynamics simulation of an HRP-4 humanoid falling on a wall