Les cartes géologiques sont un reflet des connaissances et des théories sur l’origine des granites du début du XIXe siècle jusqu’aux années 1970 et des relations anciennes entre granite et métamorphisme. Des années 1830 aux années 1870, les cartes du Royaume- Uni, de l’Allemagne, de la Norvège (à l’exception des cartes françaises), abandonnent progressivement le caractère primitif des granites, lié à la géognosie wernérienne. Elles consacrent le caractère intrusif des granites et en font des roches plutoniques à l’origine d’un métamorphisme de contact. L’émergence du microscope polarisant dans les années 1870, est à l’origine d’un renouveau de la pétrographie et coïncide avec la deuxième phase de cartographie détaillée en Europe (Allemagne, France, Royaume-Uni, Finlande). Les cartes distinguent l’âge et la diversité pétrographique des granites, et des zones d’intensité métamorphique différente. Roches éruptives ou ignées issues d’un magma liquide, les granites proviennent de la fusion pour les magmatistes, ou de l’assimilation par des agents minéralisateurs pour les transformistes. Les rééditions et révisions tout au long du XXe siècle témoignent d’une progression des idées transformistes au Royaume-Uni, et de leur hégémonie en France. Le métasomatisme et la granitisation sont responsables de la formation des migmatites et des granites, lesquels restent des roches métamorphiques jusque dans les années 1970, bien après les succès de la pétrologie expérimentale. Les complexes annulaires d’Écosse sont vus comme le résultat d’une subsidence en chaudron et l’analyse structurale des massifs développée en Allemagne apporte des arguments tectoniques quant à la mise en place des plutons. / Geological maps reflect the advanced stage of knowledge of granite and theories about its origin from the early 19th to the 1970s and show that granite and metamorphism have been tied for a long time. From the 1830s to the 1870s, granites could no longer be regarded as primitive rocks, a word of Wernerian legacy, in the United Kingdom, Germany, and Norway, with the exception of France, but were considered as plutonic and intrusive rocks which generate metamorphic aureoles in country rock. The emergence of a new method using polarising microscope in the 1870s led to the revival in petrology and coincided with the second phase of detailed geological mapping in Europe (Germany, the United Kingdom, and Finland). The Age and diversity of granites and the successive areas in metamorphism are mapped. Geologists accept the igneous origin of granite, they regard granites as eruptive or igneous rocks that are derived from liquid magma. Magmatists consider granitic magma to be the result of melting, while transformists regard this magma as the source of mineralising fluids (mineralizers) responsible for the assimilation. New editions and revised maps show that throughout the 20th century transformist ideas were on the rise in the United Kingdom and already dominant in France. Until the 1970s Granites and migmatites have to be considered in France as metamorphic rocks which have resulted from metasomatism and granitization process, despite many achievements of experimental petrology. Surveyors in Scotland recognize cauldron subsidence as the process that produces ring dykes. Structural German studies provide supporting evidence that the emplacement of plutons is affected by the tectonic conditions.

This dissertation focuses on the design and analysis of distributed primitives for mobile ad hoc networks, in which mobile hosts are free to move arbitrarily. Arbitrary mobility adds unpredictability to the topology changes experienced by the network, which poses a serious challenge for the design and analysis of reliable protocols. In this work, three different approaches are used to handle mobility. The first part of the dissertation employs the simple technique of ignoring the mobility and showing a lower bound for the static case, which also holds in the mobile case. In particular, a lower bound on the worstcase running time of a previously known token circulation algorithm is proved. In the second part of the dissertation, a self-stabilizing mutual exclusion algorithm is proposed for mobile ad hoc networks, which is based on dynamic virtual rings formed by circulating tokens. The difficulties resulting from mobility are dealt with in the analysis by showing which properties hold for several kinds of mobile behavior; in particular, it is shown that mutual exclusion always holds and different levels of progress hold depending on how the mobility affects the token circulation. The third part of the dissertation presents two broadcasting protocols which propagate a message from a source node to all of the nodes in the network. Instead of relying on the frequently changing topology, the protocols depend on a less frequently changing and more stable characteristic — the distribution of mobile hosts. Constraints on distribution and mobility of mobile nodes are given which guarantee that all the nodes receive the broadcast data.

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This thesis presents a greedy search algorithm for maneuver-based motion planning of agile vehicles. In maneuver-based motion planning, vehicle maneuvers are solved offline and saved in a library to be used during motion planning. From this library, a tree of possible vehicle states can be generated through the search space. A depth-first, library-based algorithm called AD-Lib is developed and used to quickly provide feasible trajectories along the tree. AD-Lib combines greedy search techniques with hill climbing and effective backtracking to guide the search process rapidly towards the goal. Using simulations of a four-thruster hovercraft, AD-Lib is compared to existing suboptimal search algorithms in both known and unknown environments with static obstacles. AD-Lib is shown to be faster than existing techniques, at the expense of increased path cost. The motion planning strategy of AD-Lib along with a switching controller is also tested in an environment with dynamic obstacles. / Master of Science

Avec l'évolution constante des technologies, les scanners 3D fournissent de plus en plus de données avec une précision toujours plus grande. Cependant, l'augmentation considérable de la taille des données pose des problèmes, les fichiers deviennent très lourds et il peut en découler des difficultés de transmission ou de stockage. C'est pourquoi, la plupart du temps les données obtenues par les scanners vont être analysées, traitées puis simplifiées ; on parle alors de chaine d'acquisition 3D. Ce manuscrit présente une approche qui permet de numériser les objets de manière dynamique, en adaptant la densité de points dès l'acquisition en fonction de la complexité de l'objet à numériser, et ce sans a priori sur la forme de l'objet. Ce système permet d'éviter de passer par la chaine 3D classique, en ne calculant pas un nuage de points dense qu'il faudra simplifier par la suite, mais en adaptant la densité de points au niveau de l'acquisition afin d'obtenir des données simplifiées directement à la sortie de l'acquisition, permettant ainsi de réduire considérablement le temps de traitement des données. / With constant evolution of technology, 3D scanners are providing more and more data with ever greater precision. However, the substantial increase of the data size is problematic. Files become very heavy and can cause problems in data transmission or data storage. Therefore, most of the time, the data obtained by the 3d scanners will be analyzed, processed and simplify; this is called 3D acquisition chain.This manuscript presents an approach which digitize objects dynamically by adapting point density during the acquisition depending on the object complexity, without informations on object shape. This system allows to avoid the use of the classic 3D chain. This system do not calculate a dense points cloud which will be simplify later, but it adapts the points density during the acquisition in order to obtain directly simplified data to the acquisition output. This process allows to reduce significantly processing time.

Traditionally robots have been preprogrammed to execute specific tasks. Thisapproach works well in industrial settings where robots have to execute highlyaccurate movements, such as when welding. However, preprogramming a robot isalso expensive, error prone and time consuming due to the fact that every featuresof the task has to be considered. In some cases, where a robot has to executecomplex tasks such as playing the ball-in-a-cup game, preprogramming it mighteven be impossible due to unknown features of the task. With all this in mind,this thesis examines the possibility of combining a modern learning framework,known as Learning from Demonstrations (LfD), to first teach a robot how toplay the ball-in-a-cup game by demonstrating the movement for the robot, andthen have the robot to improve this skill by itself with subsequent ReinforcementLearning (RL). The skill the robot has to learn is demonstrated with kinestheticteaching, modelled as a dynamic movement primitive, and subsequently improvedwith the RL algorithm Policy Learning by Weighted Exploration with the Returns.Experiments performed on the industrial robot KUKA LWR4+ showed that robotsare capable of successfully learning a complex skill such as playing the ball-in-a-cupgame. / Traditionellt sett har robotar blivit förprogrammerade för att utföra specifika uppgifter.Detta tillvägagångssätt fungerar bra i industriella miljöer var robotar måsteutföra mycket noggranna rörelser, som att svetsa. Förprogrammering av robotar ärdock dyrt, felbenäget och tidskrävande eftersom varje aspekt av uppgiften måstebeaktas. Dessa nackdelar kan till och med göra det omöjligt att förprogrammeraen robot att utföra komplexa uppgifter som att spela bollen-i-koppen spelet. Medallt detta i åtanke undersöker den här avhandlingen möjligheten att kombinera ettmodernt ramverktyg, kallat inläraning av demonstrationer, för att lära en robothur bollen-i-koppen-spelet ska spelas genom att demonstrera uppgiften för denoch sedan ha roboten att själv förbättra sin inlärda uppgift genom att användaförstärkande inlärning. Uppgiften som roboten måste lära sig är demonstreradmed kinestetisk undervisning, modellerad som dynamiska rörelseprimitiver, ochsenare förbättrad med den förstärkande inlärningsalgoritmen Policy Learning byWeighted Exploration with the Returns. Experiment utförda på den industriellaKUKA LWR4+ roboten visade att robotar är kapabla att framgångsrikt lära sigspela bollen-i-koppen spelet

Both man-made or natural objects contain repeated geometric elements that can be interpreted as primitive shapes. Plants, trees, living organisms or even crystals, showcase primitives that repeat themselves. Primitives are also commonly found in man-made environments because architects tend to reuse the same patterns over a building and typically employ simple shapes, such as rectangular windows and doors. During my PhD I studied geometric primitives from three points of view: their composition, simulation and autonomous discovery. In the first part I present a method to reverse-engineer the function by which some primitives are combined. Our system is based on a composition function template that is represented by a parametric surface. The parametric surface is deformed via a non-rigid alignment of a surface that, once converged, represents the desired operator. This enables the interactive modeling of operators via a simple sketch, solving a major usability gap of composition modeling. In the second part I introduce the use of a novel primitive for real-time physics simulations. This primitive is suitable to efficiently model volume-preserving deformations of rods but also of more complex structures such as muscles. One of the core advantages of our approach is that our primitive can serve as a unified representation to do collision detection, simulation, and surface skinning. In the third part I present an unsupervised deep learning framework to learn and detect primitives. In a signal containing a repetition of elements, the method is able to automatically identify the structure of these elements (i.e. primitives) with minimal supervision. In order to train the network that contains a non-differentiable operation, a novel multi-step training process is presented. / Graduate

Dissertation--Anthropology--University of Chicago, 1998. / Thèse initialement parue en 3 vol. Bibliogr. p. 455-477.

This thesis presents two main achievements. The first is a novel link-layer encryption protocol for wireless sensor networks. The protocol design aims to reduce energy consumption by reducing security-related communication overhead. This is done by merging security-related data of consecutive packets. The merging is based on simple mathematical operations. It helps to reduce energy consumption by eliminating the requirement to transmit security-related fields in the packet. The protocol is named the Compact Security Protocol and is referred to as C-Sec. In addition to energy savings, the C-Sec protocol also includes a unique security feature of hiding the packet header information. This feature makes it more difficult to trace the flow of wireless communication, and helps to minimize the effect of replay attacks. The C-Sec protocol is rigorously tested and compared with well-known related protocols. Performance evaluations demonstrate that C-Sec protocol outperforms other protocols in terms of energy savings. The protocol is evaluated with respect to other performance metrics including queuing delay and error probability. The C-Sec operation requires fast encryption, which leads to a second major contribution: The SN-Sec, a 32-bit RISC secure wireless sensor platform with hardware cryptographic primitives. The security vulnerabilities in current WSNs platforms are scrutinized and the main approaches to implementing their cryptographic primitives are compared in terms of security, time, and energy efficiency. The SN-Sec secures these vulnerabilities and provides more time and energy efficiency. The choice of cryptographic primitives for SN-Sec is based on their compatibility with the constrained nature of WSNs and their security. The AES implementation has the best data-path and S-Box design in the literature. All SHA family members are implemented and compared to choose the most compatible with WSN constraints. An efficient elliptic-curve processor design is proposed. It has the least mathematical operations compared to elliptic-curve processors proposed for WSNs in the literature. It also exploits parallelism among mathematical operations to compute elliptic-curve point multiplication with minimal amount of clock cycles. SN-Sec is implemented using VHDL. Experimental results using synthesis for Spartan-6 low-power FPGA shows that the proposed design has very reasonable computational time and energy consumption.

Le contexte de ce travail est la modélisation CAO "tel que construit" de grandes structures industrielles numérisées (usine, ...). L'environnement existant est tout d'abord numérisé à l'aide d'un scanner laser. Les données ainsi obtenues prennent la forme d'un nuage de points 3D non-structuré et non-homogène. L'étape suivante consiste à segmenter ce nuage de points et reconstruire les différentes surfaces constituant le modèle CAO de la scène. Les environnements industriels génèrent des scènes complexes par le nombre de données et d'éléments présents, mais qui se décrivent par des primitives géométriques simples: plan, sphère, cylindre, cône, tore. Les outils actuels traitant les nuages de points 3D ne permettent pas de réaliser cette segmentation de manière automatique. <br /><br />Dans cette thèse, des algorithmes ont été développés dans ce but. L'attention a en particulier été portée sur la segmentation des lignes de tuyauterie. Les solutions logicielles implémentées dans ce cadre ont été validées par des tests auprès d'utilisateurs experts des outils actuels. Les méthodes développées se caractérisent par l'utilisation au cours de la segmentation de primitives géométriques contraintes, issues de connaissances "métier" (par exemple relations de continuité ou de tangence). L'ajustement de primitive géométrique est un élément de base au sein de ces travaux. Les procédés mis en œuvre, qui utilisent une définition véritablement géométrique des primitives, montrent de bonnes performances en pratique. D'autre part, l'un des problèmes majeurs concerne les moyens de valider le modèle ajusté. La question de la validation de modèle géométrique a été examinée. Nous présentons des méthodes originales construites à partir d'outils statistiques. Enfin, une autre contribution de cette thèse se situe au niveau des algorithmes d'extraction de primitives géométriques d'un nuage de points. Les méthodes présentées ont été appliquées dans le contexte des lignes de tuyauterie, mais semblent également pertinentes pour résoudre la question plus générale de la modélisation totalement automatique d'un environnement numérisé.