A agricultura de precisão tem agregado alto valor para os agricultores por causa das tecnologias que estão ligadas a ela. Sistemas que extraem informações de imagens digitais são extremamente utilizados para que o agricultor tome decisões a fim de aumentar sua produtividade. Uma das técnicas de realizar o monitoramento é a construção de um mosaico de imagens aéreas, onde são utilizadas aeronaves voando em baixa altitude. Esta técnica pode levar dezenas de horas para ser concluída, dependendo da configuração do computador que a executa. Com o intuito de reduzir o tempo nessa construção e tornar possível o embarque a essa aplicação, este trabalho apresenta uma maneira simplificada de construir o mosaico de imagens aéreas baseada na técnica de georreferenciamento direto, no qual utiliza a computação heterogênea para acelerar o desempenho. Essa abordagem é composta por apenas três técnicas que também compõem a abordagem clássica para a construção de mosaicos (warping, extração de características e combinação de características), além de inserir em seus cálculos os dados fornecidos pelos sensores GPS e IMU com a finalidade de direcionar e posicionar cada imagem pertencente ao conjunto que formará o mosaico. A plataforma de computação heterogênea utilizada neste trabalho é a NVIDIA Jetson TK1 escolhida pelo fato de disponibilizar de uma GPU que suporta a linguagem de programação CUDA. Utilizando esta abordagem, a falta de correção da perspectiva do conteúdo (geometria) da imagem gera um resultado inesperado, pois os dados fornecidos pela IMU, ao contrário do que se imagina, apenas servem para corrigir a posição das coordenadas do GPS registradas no momento de captura de cada imagem que compõem o mosaico. O tempo de execução da aplicação desenvolvida é satisfatório tornando possível a adoção desta abordagem. / Accuracy agriculture has added value to farmers thanks to the new technologies that are linked to it. Systems that extract information from digital images are very usefull to help farmers making decisions in order to increase their productivity. One of the techniques to perform this kind of monitoring is the construction of an aerial imagery mosaic where aircrafts flies in low altitude. This technique may take hours to be completed, depending on computer\'s configuration. With the purpose of reducing time in this construction, this thesis presents a simplified way to make aerial imagery mosaic based on direct georeferencing. This approach is composed by three techniques that also make up the classic approach to building mosaics (warping, extraction of characteristics and combination of characteristics), the difference is with this technique here presented is also possible to insert into the calculations the data provided by the GPS and IMU sensors with the purpose of directing and positioning each image to the belonging set to form the mosaic. The heterogeneous computing platform used in this work is the NVIDIA JetsonTK1, this platform was chosen because it offers a GPU that supports the language of CUDA programming. If the images\' geometry errors weren\'t rectfyed, using this approach, an unexpected result happens, because the data provided by IMU, contrary to what is imagined, only serve to correct the position of the GPS coordinates recorded at the moment of capture of each image that composes the mosaic. The developing time in this application is satisfactory making the adoption of this approch favorable.

Dado um processo de Poisson d-dimensional, construímos funções harmônicas na triangulação de Delaunay associada, com comportamento assintótico linear, como limite de um processo de harness sem ruído. Tais funções permitem que construamos uma nova imersão da triangulação de Delaunay, que denominaremos de deformação harmônica. / Given a d-dimensional Poisson point process, we construct harmonic functions on the associated Delaunay triangulation, with linear assymptotic behaviour, as the limit of a noiseless harness process. These mappings allow us to find a new embedding for the Delaunay triangulation. We call it harmonic deformation of the graph.

Dado um processo de Poisson d-dimensional, construímos funções harmônicas na triangulação de Delaunay associada, com comportamento assintótico linear, como limite de um processo de harness sem ruído. Tais funções permitem que construamos uma nova imersão da triangulação de Delaunay, que denominaremos de deformação harmônica. / Given a d-dimensional Poisson point process, we construct harmonic functions on the associated Delaunay triangulation, with linear assymptotic behaviour, as the limit of a noiseless harness process. These mappings allow us to find a new embedding for the Delaunay triangulation. We call it harmonic deformation of the graph.

The dissertation thesis aims to identify and describe the key theoretical and methodological problems related to the study of conversation markers and to the collection of authentic data for such an analysis. To illustrate the whole research process, the Argentinian conversation marker boludo as a model example is used. The starting point of the analysis is located at the intersection of conversation analysis, discourse analysis and sociolinguistic paradigms, while taking into account the omnipresent background of pragmatics as well. We try to assess the contribution of such an interdisciplinary approach when studying conversation markers. As for the methodology, the thesis seeks to show what difficulties arise when carrying out a sociolinguistic research of conversation markers, which are understood as units typical of spontaneous conversation, i.e. without external manipulation, in comparison with the variationist research at other language levels. In addition, we also clarify why it is important to evaluate their character not only on the grounds of qualitative and functional perspective (in relation to analysing the socially-indexed interaction markers), but also quantitatively with regards to selected social variables that appear to be relevant for the recurrent use of the given marker. The outcome of the method assessment is an attempt to design a model approach to be applied in practice. In sum, the core of the research consists in analysing the Argentinian marker boludo from different perspectives; namely, within the pragmatic, functional-positional, interactional-sociolinguistic and variationist-sociolinguistic frameworks. Its nature is subsequently compared to the behaviour of another recurrent Argentinian conversation marker, che, since some authors regard them as equivalents. The analyses of naturally-occurring conversation data collected in situ are complemented by introspective judgements of several native speakers.

Conflict in recreation is a major problem for recreation managers who are trying to provide satisfying experiences for all recreationists. This thesis is about conflict between mountain-bikers and trampers. Mountain-biking has grown in popularity in New Zealand over the last ten years, and these increasing numbers have threatened the quality of walkers' and runners' recreational experiences, particularly in peri-urban areas. Conflict is a complex social interaction process which occurs around times of change. It involves the interplay of perceptions and attitudes, behaviour, and an incompatible situation. This complexity required the use of a range of methods to successfully understand the conflict between walkers and mountain-bikers. Like many other recreational conflicts, the conflict between bikers and trampers is asymmetrical - walkers dislike meeting bikers much more than bikers dislike meeting walkers. A majority of walker respondents disliked or strongly disliked meeting bikers on walking tracks. Walkers' questionnaire answers indicated that their greatest concerns with mountain-biking are (in order of decreasing importance) track damage and other environmental damage, personal safety, and the feeling that bikes interrupt their peace and quiet. Further exploration during in-depth interviews show that the perception of these problems are closely related to the way different users feel about that places that they use, and the way meetings with other users can be incorporated into the experiences of the recreationist. For walkers, meeting bikers is far more intrusive than vice-versa. Political activity aimed at eliminating bikers from many front country areas means that bikers are now developing a dislike of trampers who they see as intolerant and arrogant. Therefore, behaviour affects the escalation of conflict. In addition, wider social change has had an influence on this conflict. Changing economic wellbeing, less regular work hours, a perceived lack of time and a wider choice of activities have all impacted on recreation patterns in peri-urban areas, and on this conflict situation. In addition, this study has indicated that the concepts of specialisation and substitution may need modification. The use of qualitative methods has highlighted the narrow focus that researchers have used when studying these concepts. Both must be seen more broadly in the context of individuals' changing recreational needs both over the life cycle, and in the face of social change as outlined above.

Les travaux présentés dans ce mémoire d'habilitation portent sur deux aspects <br />de la modélisation géométrique de surfaces lisses. <br /><br />L'ambition des recherches menées sur le thème de l'interpolation de triangulations <br />polygonales quelconques par des surfaces polynomiales a été de revenir à la source du <br />problème en introduisant un autre découpage, régulier en quatre cette fois ci, des <br />triangles données en entrée. Nous présentons de nouvelles approches en insistant sur <br />la résolution du problème de raccordement lisse de patchs triangulaires en un sommet <br />commun ainsi que sur le choix optimal des paramètres de forme permettant de contrôler <br />la qualité esthétique de la surface. De plus, l'invariance par subdivision d'un des <br />schémas permet une hiérarchisation des procédés d'interpolation. Il devient alors<br />possible d'avoir un modèle de surface multirésolution paramétrique, et permettant <br />de décrire de topologies quelconques, applicable dans des domaines aussi divers que <br />la CAO, la réalité virtuelle ou la médecine.<br /><br />Le deuxième thème concerne le lissage de surfaces B-splines. Deux types de méthodes, <br />basées sur la diminution de la variation de courbures, sont présentés. Les premières <br />utilisent des stratégies de recherche heuristiques ou systématiques. Les secondes <br />reposent sur la convolution du réseau des points de contrôle de la surface par des <br />filtres discrets.

Les travaux présentés dans ce mémoire portent sur deux aspects de la modélisation géométrique de surfaces lisses. L'ambition des recherches menées sur le thème de l'interpolation de triangulations polygonales quelconques par des surfaces polynomiales a été de revenir à la source du problème en introduisant un autre découpage, régulier en quatre cette fois ci, des triangles données en entrée. Nous présentons de nouvelles approches en insistant sur la résolution du problème de raccordement lisse de patchs triangulaires en un sommet commun ainsi que sur le choix optimal des paramètres de forme permettant de contrôler la qualité esthétique de la surface. De plus, l'invariance par subdivision d'un des schémas permet une hiérarchisation des procédés d'interpolation. Il devient alors possible d'avoir un modèle de surface multirésolution paramétrique, et permettant de décrire de topologies quelconques, applicable dans des domaines aussi divers que la CAO, la réalité virtuelle ou la médecine. Le deuxième thème concerne le lissage de surfaces B-splines. Deux types de méthodes, basées sur la diminution de la variation de courbures, sont présentés. Les premières utilisent des stratégies de recherche heuristiques ou systématiques. Les secondes reposent sur la convolution du réseau des points de contrôle de la surface par des filtres discrets.

L'acquisition de modèles 3D des scènes réelles trouve son utilité dans de nombreuses applications pratiques, comme l'archivage numérique, les jeux vid eo, l'ingénierie, la publicité. Il existe principalement deux méthodes pour acqu érir un modèle 3D: la reconstruction avec un scanner laser (méthode active) et la reconstruction à partir de plusieurs photographies d'une même scène prise dans des points de vues différents (méthode passive). La méthode passive, ou la stéréo multi-vues est en revanche plus flexible, facile à mettre en oeuvre avec une grande précision, et surtout moins couteuse que la méthode active. Cette thèse s'attaque au problème de la reconstruction de stereo multi-vues à grande échelle . Nous améliorons des méthodes précédentes et les assemblons pour créer une chaine de stereo multi-vues efficace tirant parti de l'accélération des cartes graphiques. La chaîne produit des maillages de qualité à partir d'images de haute résolution, ce qui permet d'atteindre les meilleurs scores dans de nombreuses évaluations. Aux plus grandes échelles, nous développons d'une part des techniques de type diviser-pour-régner pour reconstruire des morceaux partiaux de la scène. D'autre part, pour combiner ces résultats séparés, nous créons une nouvelle méthode qui fusionne rapidement des centaines de maillages. Nous réussissons à reconstruire de beaux maillages urbains et des monuments historiques précis à partir de grandes collections d'images (environ 1600 images de 5M Pixel).

In this thesis the novel concept of Sycophant Wireless Sensors (SWS) is introduced. A SWS network is a static ectoparasitic clandestine sensor network mounted incognito on a mobile agent using only the agent&rsquo / s mobility without intervention. SWS networks not only communicate with each other through mobileWireless Sensor Networks (WSN) but also cooperate with them to form a global hybrid Wireless Sensor Network. Such a hybrid network has its own problems and opportunities, some of which have been studied in this thesis work. Assuming that direct position measurements are not always feasible tracking performance of the sycophant using range only measurements for various communication intervals is studied. Then this framework was used to create a hybrid 2D map of the environment utilizing the capabilities of the mobile network the sycophant. In order to show possible applications of a sycophant deployment, the sycophant sensor node was equipped with a laser ranger as its sensor, and it was let to create a 2D map of its environment. This 2D map, which corresponds to a height dierent than the follower network, was merged with the 2D map of the mobile network forming a novel rough 3D map. Then by giving up from the need to properly localize the sycophant even when it is disconnected to the rest of the network, a full 3D map of the environment is obtained by fusing 2D map and tracking capabilities of the mobile network with the 2D vertical scans of the environment by the sycophant. And finally connectivity problems that arise from the hybrid sensor/actuator network were solved. For this 2 new connectivity maintenance algorithms, one based on the helix structures of the proteins, and the other based on the acute triangulation of the space forming a Gabriel Graph, were introduced. In this new algorithms emphasis has been given to sparseness in order to increase fault tolerance to regional problems. To better asses sparseness a new measure, called Resistance was introduced, as well as another called updistance.

Cette thèse a pour objet la quantification de la défonnation tectonique actuelle, c'est-à-dire au cours des quelques dernières décennies, dans les Alpes du sud et la Provence, à partir de données géodésiques. Nous avons utilisé des mesures géodésiques réalisées entre 1887 et 1994 pour estimer des taux de déformations horizontales dans le sud-est de la France. Cette région qui occupe une position de carrefour complexe entre plusieurs domaines tectoniques (les Alpes, le bassin Ligure et le bloc corso-sarde) ne montre qu'un faible niveau d' activité tectonique. A partir de la combinaison de triangulations historiques réalisées pour la plupart en 1947-52 et en 1981-83 (complétées par quelques données de 1887-1931) et de données de campagnes GPS 1993 et 1994, nous calculons les taux de cisaillement angulaire dans plusieurs sous-réseaux géodésiques. Nous montrons que les taux de cisaillement sont pour un grand nombre inférieurs à leurs incertitudes, qui sont d'environ 0.1 urad/an. Ces résultats impliquent que les failles de la Durance et de Nîmes, les deux accidents tectoniques majeurs de la Provence et du Languedoc, sont très faiblement actifs. Nous pouvons alors donner une borne supérieure de 1 à 2 mm/an sur les taux de glissement sur ces deux failles, en supposant,des zones de failles de 20 km de large pour chacune. Dans le front de la nappe de Castellane, nous mettons en évidence des taux de cisaillement angulaire significatifs. Pour cette région, nous calculons une composante du taux de cisaillement angulaire de -0.16 ± 0.08 urad/an, que nous interprétons comme le résultat d'une compression NE-SW. Au sud du Pelvoux, nous obtenons des composantes du taux de cisaillement élevées par rapport aux valeurs obtenues dans les sous-réseaux situés en Provence et en Languedoc, et pouvant atteindre -0.17 ± 0.07 urad/an. Cette valeur importante concerne une région au voisinage du séisme de Haute-Ubaye de 1959 de magnitude 5.3 dont le mécanisme au foyer indique également une compression NE-SW. On ne peut cependant pas rejeter un biais lié à une hétérogénéité dans les données géodésiques. Finalement, nous pouvons intégrer ces résultats dans la géodynamique du sud-est de la France. Les taux de cisaillement significatifs sont élevés dans les régions proches du Front Pennique, la limite majeure entre les Alpes internes et externes, où il y aurait une déformation soulignée par une sismicité soutenue; tandis que la Provence et le Languedoc, peu sismiques, ont des taux de déformation plus faibles.