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International audience; Industrial woven meshes are composed of metal material and are often used in construction, industrial and residential industries. The context of this work is defect detection in industrial fabrics in the quality control process. It is often performed with a manual method and could be quite tedious and time-consuming. We propose here a method to automatically detect defects in micrometric steel meshes using a Convolutional Neural Network. The database used for this work comes from the real problem of anomaly detection on micrometric woven meshes. This detection is performed through supervised classification with Convolutional Neural Network using a VGG19 architecture. To this aim, we propose a pipeline and a strategy to tackle the small amount of data. It includes i) augmenting the database with translation, rotation and symmetry, ii) using pre-trained weights and iii) checking the learning curve behaviour through cross-validation. The proposed method has been evaluated by automatically detecting if metallic fabrics has defects. Obtain results show that, despite the small size of our databases, detection accuracy of 96% was reached.

International audience; In this paper, we propose a novel accelerated alternating optimization scheme to solve block-biconvex nonsmooth problems whose objectives can be split into smooth (separable) regularizers and simple coupling terms. The proposed method performs a Bregman distance based generalization of the well-known forward-backward splitting for each block, along with an inertial strategy which aims at getting empirical acceleration. We discuss the theoretical convergence of the proposed scheme and provide numerical experiments on image colorization.

International audience; Active contours (also known as snakes) have shown their ability to introduce regularity on image segmentation. In contrast with level-set approaches, the active contours techniques based on a contour parameterization are able to maintain the initial topology of the area of interest. For this reason, it has been used in recent medical research for diaphragm segmentation. Most of the on-line codes for 2D/3D segmentation, as well as built-in Matlab toolboxes are based on level-set methods. Moreover, in the literature, the implementation details of active contours methods with meshes in three dimensions are tight, making tedious any reproduction of these techniques. In this paper, we give some details of the implementation of active contours in 2D/3D with meshes, especially about the choice of the use of a 2D/3D mesh and its refinement. We also explore the choice of the parameters with a quantitative study of their influence on the segmentation results. The 3D segmentation method has been applied to CT scan images of the lungs.

A global health crisis has led countries to implement containment measures that affect the entire tourism chain. This study evaluates the prospects for the revival of travels to nature-based destinations through an assessment of international trends and analysis of local actors’ discourses. For international experts it is an urbanization of the planet and hyper-mobilities, in a scenario of climate change, which has triggered the current pandemic. They feel the recovery of the sector could be very slow. In the Region of Aysén, Chile, we observe that everyone hopes to soon be able to welcome a national urban clientele eager for unpolluted areas. However, when entrepreneurs hope to resume their activities, the local community prefers to withdraw, afraid of the risk of attending to visitors. For its part, the state has established health measures and plans to open up the region to visitors through strict safety protocols, but with subsidies that are too limited to prevent many businesses from closing. The pandemic could favour emerging natural destinations, but this requires the consolidation of the destination as a place to live and a qualitative and not quantitative tourism, less subject to international uncertainties, relevant to the regional community and respectful of the environment., Una crisis sanitaria mundial ha llevado a los países a implementar medidas de confinamiento que afecta a toda la cadena turística. Este estudio evalúa las pers-pectivas para su reactivación en destinos de naturaleza, mediante una evaluación de las tendencias internacionales y el análisis de discursos de actores locales. Para expertos internacionales es una urbanización del planeta y las hipermovilidades, en un escenario de cambio climático, que ha gatillado la actual pandemia y la recuperación del sector podría ser muy lenta. En la región de Aysén, Chile, se observa que todos esperan poder acoger pronto una clientela nacional urbana atraída por zonas naturales no contaminadas. Sin embargo, cuando los empresarios esperan poder retomar sus actividades, la comunidad local prefiere replegarse, asustada por el riesgo de atender a visitantes. Por su parte, el estado establece medidas sanitarias y plantea a futuro abrir la región a los visitantes mediante estrictos protocolos de seguridad pero con subsidios aún muy limitados para evitar el quiebre de muchas empresas hasta entonces. La pandemia podría favorecer destinos emergentes de naturaleza pero esto obliga a consolidar el destino como un lugar de vida en torno a un turismo cualitativo y no cuantitativo, menos sujeto a las incertidumbres internacionales, relevante para la comunidad regional y respetuosa con el medioambiente.

International audience; We propose to detect defects in old movies, as the first step of a larger framework of old movies restoration by inpainting techniques. The specificity of our work is to learn a film restorer's expertise from a pair of sequences, composed of a movie with defects, and the same movie which was semi-automatically restored with the help of a specialized software. In order to detect those defects with minimal human interaction and further reduce the time spent for a restoration, we feed a U-Net with consecutive defective frames as input to detect the unexpected variations of pixel intensity over space and time. Since the output of the network is a mask of defect location, we first have to create the dataset of mask frames on the basis of restored frames from the software used by the film restorer, instead of classical synthetic ground truth, which is not available. These masks are estimated by computing the absolute difference between restored frames and defectuous frames, combined with thresholding and morphological closing. Our network succeeds in automatically detecting real defects with more precision than the manual selection with an all-encompassing shape, including some the expert restorer could have missed for lack of time.

International audience; La Patagonie attire les voyageurs depuis plusieurs siècles. Aujourd'hui, le tourisme s'y développe rapidement avec des conséquences environnementales, culturelles et sociales qui menacent une nature sauvage et ses habitants. Quelle est la part d'imaginaire et de vérité autour du mythe de la Patagonie ? Quelle est cette nature que nous recherchons en y voyageant ? Que devient cette Patagonie à l'aune du boom touristique ? La Patagonie deviendra-t-elle ce que ses habitants et voyageurs veulent ? Un havre de paix écologique, un terrain de jeux et d'explorations, une plateforme pour de bonnes affaires ? Par une approche socio-géographique de confins touristiques de la nature, ce livre montre que les dynamiques territoriales sont le résultat de représentations du monde et de justifications socio-économiques opposées. Elles se traduisent par sept formes de développement touristique : étatique, industrielle, traditionaliste, entrepreneuriale, écologique, alternative et récréative. Chacun cherche à promouvoir son usage de la nature, « progressiste », pour le bien de l'humanité, « anthropocentrique », pour satisfaire nos besoins vitaux, ou « écologique », une nature dont nous sommes partie intégrante et à qui nous devons le respect. Il en résulte des affrontements idéologiques et culturels. Cependant, ils peuvent se fédérer autour d'un projet territorialisé, culturel plus que commercial, lorsqu'un médiateur facilite une approche collective, appropriée localement.

International audience; We propose a new video inpainting model for movies restoration application. Our model combines structural reconstruction with a diffusion-based method and textural reconstruction with a patch-based method. Both proposed energies (one for each method) are alternatively minimized in order to preserve the overall structure while adding textural refinement. While the structural reconstruction is obtained jointly with optical flow computation with several proximal approaches, the textural reconstruction is processed by a variational non-local approach. Preliminary results on different Middlebury frames show quality improvement in the reconstruction.

International audience; (2019): "El turismo científico y su influencia en la comunidad local: el estudio de caso de la red de turismo científico en Aysén, Chile", Revista Turydes: Turismo y Desarrollo, n. 26 (junio/junho 2019). En línea: https://www.eumed.net/rev/turydes/26/aysen-chile.html http://hdl.handle.net/20.500.11763/turydes26aysen-chile RESUMEN Lugares emergentes como la región de Aysén al sur de Chile, son ejemplo de territorios que debido a su aislamiento geográfico, se han convertido en el escenario perfecto para plantear diferentes alternativas turísticas ante la creciente masificación global del turismo. El turismo es una de las actividades económicas preponderantes en la región, lo que socialmente ha incitado a algunos actores locales a (re)pensar y (re)estructurar prácticas turísticas que favorezcan y respondan de mejor forma a las necesidades y condiciones locales de Aysén. De la mano de alternativas como el llamado Turismo Científico, se discute como este tipo de propuestas buscan y exploran incentivar la organización social a través de un proyecto común que estrecha la relación entre la ciencia y los distintos actores involucrados con el turismo. Como parte del proyecto ECOS Sur C15H01 del Centro de Investigación en Ecosistemas de la Patagonia (CONICYT R10C1003), el presente estudio de caso, analiza un cumulo de entrevistas realizadas a actores locales relacionados con sectores como la investigación, la academia, las organizaciones de la sociedad civil, las instituciones gubernamentales y el sector turístico; con el fin de obtener una mirada acerca de la influencia que representa la Red de TC entorno al aprovechamiento y protección de los recursos naturales y culturales en la región de Aysén. Palabras clave: Turismo científico, alternativa turística, masificación turística, organización social.

Territorial dynamics are the result of a games of actors within a given geographical area. Understanding them involves identifying the actors' strategies and their relationship to the territory. The gradual investment of at the frontier of civilization to the tourism economy induces significant socio-spatial changes. What are the socio-geographical logics that characterize the tourism transformation of the nature borderlands? The dynamics of tourism destinations are extensively studied but those of nature's borderlands are not. Marginal, peripheral or frontier places are strong in the traveler's imaginaries, they are exotic and constitute geographical objects of their own [part I]. In an ever more urbanized world, the lesser-known areas of nature, defined as Wilderness in the Anglo-Saxon culture, are attracting evermore tourists of all origins.The analysis of the physical particularities, statistical and cartographic data of Touristic Nature Borderland shows the spatial relevancy of the notion. A critical analysis of nature tourism actors' speeches shows their the social-cultural attributes and the imaginaries associated to them. Nature territories are social constructs, they result of a unique cultural organization. Different social representations, individual or collective, generate actor's speeches and actions. They build different Tourism Development Forms that have different logics; state, industrial, traditionalist, entrepreneurial, ecological, alternative or recreational [Part II].The appearance of a form depends on historical and cultural conditions of a territory. It is possible to identify them on a nature area by analyzing tourism actor's speeches and the spatial materiality which result from their actions. The dynamics at work in a recreational area are the result of the existing relationships between group of actors with different conceptions of development. Confrontations and agreements between Tourism Development Forms arise in time and space [part III]. Despite distinct representations of nature and economical justifications, they can unite against a threat to their interests. This is the case, for example, during environmental conflicts, around the industrial use of water resources. On the other hand, public policies wanting to promote the economic development of the territory tend to support only one form of development and thus favor ideological confrontations. The analysis of public and private projects in the region of Aysén in Chilean Patagonia, shows that these favor in partial manner certain actors of the territory. Only some projects, such as scientific tourism, manage to unite actors. This is made possible by empowering them trough a territorial project, cultural rather than commercial, based on the sharing of knowledges and the specification of the tourism resources. The work of a facilitator and mediator, in charge of territorial engineering, insures the collective initiative.A reading through the Tourism Development Forms proves particularly relevant for emerging systems. The study of the existing conflicts in Nature based Borderlands reveals processes that are characteristic of modern societies, tourism being at the heart of the contradictions of our civilization anchored in the metropolis.; Les dynamiques territoriales sont le résultat des jeux d'acteurs au sein d'un espace géographique déterminé. Les comprendre suppose de cerner les stratégies d'acteurs et leurs rapports au territoire. L'ancrage progressif d'un espace à la frontière de l'écoumène dans l'économie du tourisme induit des changements socio-spatiaux importants. Quelles logiques sociogéographiques caractérisent alors la mise en tourisme des confins de nature ? Les dynamiques des destinations touristiques sont abondamment étudiées, mais celles des confins de nature ne le sont pas. Lieux marginaux, périphériques ou frontaliers, ils sont omniprésents dans les imaginaires du voyage, car chargés d'altérité, et constituent des objets géographiques à part entière [partie I]. Dans un monde toujours plus urbanisé, les confins de nature les moins connus, qualifiés de Wilderness par les Anglo-saxons, attirent de plus en plus les touristes de toutes origines.L'analyse des spécificités physiques, des données statistiques et cartographiques des confins touristiques de nature montre la pertinence spatiale de la notion. L'interprétation des discours d'acteurs du tourisme de nature permet d'en préciser les attributs sociaux culturels et les imaginaires qui s'y rattachent. Les territoires de nature sont des construits sociaux, le produit d'une organisation culturelle singulière. Différentes représentations sociales, individuelles ou collectives, produisent des discours et des logiques d'acteurs. Il en résulte différentes formes de développements des espaces touristiques, qui sont étatiques, industrielles, traditionalistes, entrepreneuriales, écologiques, alternatives ou récréatives [partie II].L'apparition d'une forme dépend de conditions historiques et culturelles sur un territoire. Il est possible de les identifier sur un espace de nature grâce à l'analyse du discours des acteurs du tourisme et aux matérialités spatiales qui résultent de leurs actions. Les dynamiques à l'œuvre sur un territoire de pratiques récréatives sont tributaires des rapports qu'entretiennent des collectifs d'acteurs ayant des conceptions différenciées du développement. Des confrontations et des compromis entre des formes de développement touristique s'établissent dans le temps et dans l'espace [partie III]. Malgré des représentations de la nature et des justifications économiques distinctes, celles-ci peuvent s'unir face à une menace affectant leurs intérêts. C'est le cas, par exemple, lors des conflits environnementaux, autour de l'usage industriel des ressources hydriques. En revanche des politiques publiques voulant favoriser le développement économique du territoire tendent à n'appuyer qu'une forme de développement et attiser alors les affrontements idéologiques. L'analyse des projets publics et privés dans la région d'Aysén en Patagonie chilienne montre que les projets d'États favorisent de manière partiale certains acteurs du territoire. Seuls certains projets, tels que celui du tourisme scientifique, parviennent à fédérer les acteurs. Ceci est rendu possible par un processus de participation active à un projet territorialisé, culturel plus que commercial, basé sur le partage de connaissances et une spécification de la ressource touristique. L'action d'un animateur et médiateur, responsable de l'ingénierie territoriale, assure la mise en œuvre de l'initiative collective.Une lecture par les formes de développement touristique apparait comme particulièrement pertinente pour caractériser les systèmes émergents. L'étude des tensions à l'œuvre dans les confins de nature révèle des processus caractéristiques des sociétés contemporaines, le tourisme étant au cœur des contradictions de nos civilisations ancrées dans les métropoles.

International audience; This paper focuses on the denoising of chrominance channels of color images. We propose a variational framework involving TV reg-ularization that modifies the chrominance channel while preserving the input luminance of the image. The main issue of such a problem is to ensure that the denoised chrominance together with the original luminance belong to the RGB space after color format conversion. Standard methods of the literature simply truncate the converted RGB values, which lead to a change of hue in the denoised image. In order to tackle this issue, a " RGB compatible " chrominance range is defined on each pixel with respect to the input luminance. An algorithm to compute the orthogonal projection onto such a set is then introduced. Next, we propose to extend the CLEAR debiasing technique to avoid the loss of colourfulness produced by TV regularization. The benefits of our approach with respect to state-of-the-art methods are illustrated on several experiments.

Colorization of gray-scale images relies on prior color information. Exemplar-based methods use a color image as source of such information. Then the colors of the source image are transferred to the gray-scale target image. In the literature, this transfer is mainly guided by texture descriptors. Face images usually contain few texture so that the common approaches frequently fail. In this paper, we propose a new method taking the geometric structure of the images rather their texture into account such that it is more reliable for faces. Our approach is based on image morphing and relies on the YUV color space. First, a correspondence mapping between the luminance Y channel of the color source image and the gray-scale target image is computed. This mapping is based on the time discrete metamorphosis model suggested by Berkels, Effland and Rumpf. We provide a new finite difference approach for the numerical computation of the mapping. Then, the chrominance U,V channels of the source image are transferred via this correspondence map to the target image. A possible postprocessing step by a variational model is developed to further improve the results. To keep the contrast special attention is paid to make the postprocessing unbiased. Our numerical experiments show that our morphing based approach clearly outperforms state-of-the-art methods.

International audience; This paper deals with the difficult problem of video colorization. Methods in the literature are generally based on spatio-temporal video blocks, or on frame to frame color propagation methods, each technique having its own advantages and drawbacks. In this paper , we present both a novel automatic frame-to-frame propagation approach and an interactive correction method within a variational framework. The proposed method propagates colors from an initial colorized frame to the whole grayscale video sequence. The automatic propagation results may be visually unsuitable in some cases. To overcome this limitation, a spatio-temporal functional with a user-guided correction is introduced. Two primal-dual algorithms are designed to solve the proposed variational models. Numerical results show the efficiency and the potentiality of the proposed approach in comparison with state-of-the-art methods.

International audience; The aim of this paper is twofold. First, we propose a new method for enhancing the contrast of gray-value images. We use the difference of the average local contrast measures between the original and the enhanced images within a variational framework. This enables the user to control the contrast level and the scale of the enhanced details intuitively. Moreover, our model avoids large modifications of the original image histogram. Thereby it preserves the global illumination of the scene and can cope with large areas having similar gray values. The minimizer of the proposed functional is computed by a gradient descent algorithm in connection with a polynomial approximation of the average local contrast measure. The polynomial approximation is done via Bernstein polynomials and leads to to a speed up of the algorithm by applying fast Fourier transforms. In the second part, the approach is extended to a variational enhancement method for color images. The model approximately preserves the hue of the original image and includes additionally a total variation term to correct possible noise. The method requires no post-or pre-processing. The minimization problem is solved with a hybrid primal-dual algorithm. Numerical experiments demonstrate the efficiency and the flexibility of the proposed approaches in comparison with state-of-the-art methods.

International audience; This paper proposes a novel model for contrast enhancement of RGB images. The average local contrast measure is increased within a variational framework which preserves the hue of the original image by coupling the channels. The user is enabled to intuitively control the level of the contrast as well as the scale of the enhanced details. Moreover, our model avoids large modifications of the original image his-togram and thereby preserves the global illumination of the scene. The minimizer of the proposed functional is computed by a hybrid primal-dual algorithm. Numerical experiments show the reliability of the proposed approach in comparison with state-of-the-art methods.

With the advent of the microelectronics and the "smart-devices", the need for micro-sources of energy has risen. To meet these needs, a massive production of microbatteries is required in the next decades. Physical vapor deposition (PVD) is the process commonly used to fabricate thin film all solid state microbatteries. Commercially, LiCoO2 and lithium are used respectively as positive and negative electrodes. LiPON is commonly used as solid electrolyte because of its good ionic conductivity, good thermal and electrochemical stability and also for its good interfacial stability with the electrodes. However, the PVD process requires very expensive deposition machineries, with a high energy cost, which impact consequently the price and the development of the microbatteries. Processes involving liquid step, such as ink jet printing or screen printing propose cheaper machinery and much higher production rate. Moreover, these techniques are precise enough to deposit any pattern either by located drop jetting or by use of specific mask fitting the desired shape. In this communication, we will report our efforts to develop all or partially printed microbatteries. We have worked on replacing LiPON by another solid electrolyte which could be deposited by printing. Ionogels are solid electrolyte in which an ionic liquid (IL) is confined within a solid host network. Although solid like electrolytes, ionogels are formed from a liquid precursor, and are thus appropriate materials for the purpose. The liquid precursor is obtained by mixing the IL with organic, inorganic or hybrid monomers that are then polymerized to build in-situ the confining network. Furthermore, ionogels show good ionic conductivity and also good thermal and electrochemical stability, thus making them attractive solid electrolyte for lithium batteries. The time required to form a fully solidified material can vary depending on the nature of the confining network and the polymerization process. By using photo-polymerization, which is very fast, the manufacturing time is lesser than an hour, while for LiPON it can last more than ten hours. We have identified a promising printable photo-polymerizable ionogel composition with high ionic conductivity, pressure-sensitive-adhesive character, low interface resistance with lithium electrode, which allows stable cycling of LiFePO4/lithium cells, at least up to 1200 cycles at ambient temperature, C/5 rate and for surface capacities typical of microbatteries, e.g. 0.15 mAh cm-2. This ionogel is based on short molecular weight monomers with high content of polymerizable functionalities (triacrylate and diacrylate) and ILs composed of fluorinated sulfonylimide anions combined with alkylated pyrrolidinium cations [1]. We have evaluated the feasibility of making all or partially printed microbatteries with this printable solid electrolyte, not starting from the ground but trying to fit in an existing industrial process that uses PVD for manufacturing microbatteries. Microbatteries assembled from a dense PVD made LiCoO2 layer, a printed photo-polymerized ionogel, and a lithium layer exhibit good performance. However, the photo-polymerized ionogel showed very low compatibility when the lithium electrode is directly deposited by PVD on the top of it. Thus the lithium electrode must be mechanically assembled with the ionogel electrolyte. Microbatteries assembled from a printed porous LiFePO4 composite layer [2], a printed photo-polymerized ionogel, and lithium layer (an already made foil or evaporated layer and mechanically pressed on the ionogel surface) also demonstrated good performance. Acknowledgements Financial funding from the project TOURS 2015 n° O12590-418393 (Programme d’Investissement d’Avenir – FSN – AAP Nanoélectronique n°1) is acknowledged. References [1] D. Aidoud, A. Etiemble, D. Guy-Bouyssou, E. Maire, J. Le Bideau, D. Guyomard, B. Lestriez, "Interfacial stability and electrochemical behavior of Li/LiFePO4 microbatteries using novel soft and weakly adhesive photo-ionogel electrolytes”, J. Power Sources, 330, 2016, 92-103. [2] P.-E. Delannoy, B. Riou, T. Brousse, J. Le Bideau, D. Guyomard, B. Lestriez, “Ink-jet printed porous composite LiFePO4 electrode from aqueous suspension for microbatteries”, J. Power Sources, 2015, 287, 261-268.

International audience

Since 2007 the Center for Research in Patagonian Ecosystems (Centro de Investigación en Ecosistemas de la Patagonia, CIEP) has implemented Scientific Tourism (ST) to foster research programs, technology transfer and scientific mediation in order to strengthen a sustainable tourism development in remote and understudied areas of Chile. This participatory process where some 40 public and private entities of Chile, South America, USA and Europe collaboratehas supported research on cultural heritage and natural processes of southern mountainous areas.Scientific Tourism is defined as special interest tourism that generates and shares acquired knowledge. It can be considered as a niche such aslearning and experiential tourism, but has wider implications and benefits. In a previous research four forms of worldwide tourism practices have been described by Mao&Bourlon (2011): 1) Exploration and adventure Tourism with a scientific dimension, 2) Cultural Tourism based on scientific knowledge, 3) Scientific ecovolunteering and 4) Scientific research tourism.Through the analysis of Scientific Tourism activities in mountainous areas and surrounding rural and coastal zones, the present work studies how research programs, tourism dynamics and local empowerment can be used as management tool for remote areas. Tourism like industrial fishing, salmon farming and hydro-electrical or mining projects generated impacts on the ecosystem, yet Scientific Tourism seems to meet the challenge of improving socio-economic growth of the local communities and potentially improve the conservation of highly fragile ecosystems. Gathering and sharing knowledge of natural a cultural heritage is attractive to all actors, regardless of the potentially implications of the findings of these participatory research programs. Guided by the idea of “acquiring knowledge in order to value and protect” the “Scientific Tourism” network has united some 80 local operators and public and non-profit organizations since 2011. Researchers, tourism operators, volunteers, professors, students and independent travellers have taken part in multidisciplinary, participatory and co-constructed actions to value local understudied patrimony. Actors have shared views and knowledge to support scientific expeditions and dissemination of research results. The creation of a scientific travel guide, field observation tools and “scientific knowledge” maps with an online data base with spatial references to “hot spots” for scientific tourism and product brochure for travelers are some of the results produced by this scientific and non specialist collaboration.The tourism destination of Aysén is becoming the first international destination for scientific tourism, recognized both by Chilean authorities and social networks.Scientific Tourism in Aysén has strengthened awareness on the benefit of linking knowledge, conservation and socio-economical development with participatory research schemes and could be replicated to other territories., Depuis 2007, le Centre de recherche sur les écosystèmes de Patagonie (Centro de Investigación en Ecosistemas de la Patagonia, CIEP) a mis en œuvre un Tourisme Scientifique (TS) pour favoriser les programmes de recherche, de transfert de technologie et de médiation scientifique, afin de renforcer le développement du tourisme durable dans des zones montagnardes reculées de Patagonie. Des institutions publiques et privées du Chili, d’Amérique du Sud, des Etats Unis et d’Europe ont participé à ce processus et appuyé de nouvelles recherches sur le patrimoine culturel et les processus naturels du sud chilien. Le Tourisme Scientifique peut-être défini comme une forme de tourisme d’intérêt spécifique qui génère et partage des connaissances acquises. Il peut être considéré comme une niche au même titre que le tourisme éducatif ou expérientiel, tout en ayant des répercussions et des retombées positives plus larges. Grâce à l’analyse de l’utilisation par le CIEP du tourisme scientifique pour favoriser la recherche, à travers de projets pilotes, ce document examine comment la science devient une ressource spécifique pour un développement socio-économique appropriée. Le tourisme scientifique semble relever le double défi de l’amélioration des conditions socio-économique des communautés locales et d’améliorer la mise en valeur et conservation d’écosystèmes fragiles.

International audience; La Patagonie depuis le XVe siècle attire les Européens. Cette attirance résulte de divers motifs avec une évolution dans le temps et dans l'espace. La Patagonie est un lieu propice aux utopies. Celle de la « Cité des Césars » (« Ciudad de los Cesares ») de la période coloniale, de « la Nouvelle Galle » du pasteur Jones, du royaume d'Araucanie d'Antoine Aurélie Premier, mais aussi celles des chercheurs d'or, des sociétés agricoles et industrielles, et celle des colons dans le cadre de ladite « Loi de Colonisation » de 1937. Alors qu'Aysén semble entrer lentement dans une ère de « modernité » apparaissent dès les années 1980 de nouvelles « utopies » individuelles, celles de « philanthropes verts », étrangers et chiliens, d'entrepreneurs verts « éco-touristiques », en même temps que le concept de « Aysén Reserva de Vida ». Quelles sont les incidences de ces nouveaux imaginaires dans un contexte de développement touristique ? S'agit-il des révolutions dans le mode de penser et de développer la Patagonie chilienne ? « Aysén Réserve de Vie » est-il simplement un mouvement cherchant à contrecarrer l'ultralibéralisme chilien et la globalisation industrielle à l'oeuvre en Patagonie ? S'agit-il d'une nouvelle utopie ?

This paper addresses the topic of image colorization that consists in converting a gray-scale image into a color one. In the literature, there exist two main types of approaches to tackle this problem. The first one is the manual methods where the color information is given by some scribbles drawn by the user on the image. The interest of these approaches comes from the interactions with the user that can put any color he wants. Nevertheless, when the scene is complex many scribbles must be drawn and the interactive process becomes tedious and time-consuming. The second category of approaches is the exemplar-based methods that require a color image as input. Once the example image is given, the colorization is generally fully automatic. A limitation of these methods is that the example image needs to contain all the desired colors in the final result. In this paper, we propose a new framework that unifies these two categories of approaches into a joint variational model. Our approach is able to take into account information coming from any colorization method among these two categories. Experiments and comparisons demonstrate that the proposed approach provides competitive colorization results compared to state-of-the-art methods.

International audience; This paper deals with the problem of image colorization. A model including total variation regularization is proposed. Our approach colorizes directly the three RGB channels, while most existing methods were only focusing on the two chrominance channels. By using the three channels, our approach is able to better preserve color consistency. Our model is non convex, but we propose an efficient primal-dual like algorithm to compute a local minimizer. Numerical examples illustrate the good behavior of our algorithm with respect to state-of-the-art methods.

International audience; This paper provides a new method to colorize gray-scale images. While the computation of the luminance channel is directly performed by a linear transformation, the colorization process is an ill-posed problem that requires some priors. In the literature two classes of approach exist. The first class includes manual methods that need the user to manually add colors on the image to colorize. The second class includes exemplar-based approaches where a color image, with a similar semantic content, is provided as input to the method. These two types of priors have their own advantages and drawbacks. In this paper, a new variational framework for exemplar-based colorization is proposed. A nonlocal approach is used to find relevant color in the source image in order to suggest colors on the gray-scale image. The spatial coherency of the result as well as the final color selection is provided by a nonconvex variational framework based on a total variation. An efficient primal-dual algorithm is provided, and a proof of its convergence is proposed. In this work, we also extend the proposed exemplar-based approach to combine both exemplar-based and manual methods. It provides a single framework that unifies advantages of both approaches. Finally, experiments and comparisons with state-of-the-art methods illustrate the efficiency of our proposal. 1. Introduction. The colorization of a gray-scale image consists of adding color information to it. It is useful in the entertainment industry to make old productions more attractive. The reverse operation is based on perceptual assumptions and is today an active research area [28], [13], [37]. Colorization can also be used to add information in order to help further analysis of the image by a user (e.g., sensor fusion [43]). It can also be used for art restoration ; see, e.g., [17] or [41]. It is an old subject that began with the ability of screens and devices to display colors. A seminal approach consists in mapping each level of gray into a color-space [18]. Nevertheless, all colors cannot be recovered without an additional prior. In the existing approaches, priors can be added in two ways: with a direct addition of color on

Oxidation catalysts play an important role in a variety of industrial processes. These include stain bleaching in detergent applications, the bleaching of raw cotton and wood pulp, defined chemical transformations in the bulk chemical industry, and the drying of alkyd-based paints. In order to lower the environmental footprint of these processes, the use of highly atom efficient oxidants such as dioxygen or hydrogen peroxide and the use of catalysts based on environmentally benign metals such as manganese or iron are preferred. The mechanistic studies on Mn-tacn- and Fe-bispidon-based catalysts (tacn: 1,4,7-triazacyclononane; bispidon: 3,7-diazabicyclo[3.3.1]nonan-9-one) as well as their various oxidative application areas are reviewed in more detail, including discussion of the similarities of the fundamental chemistry involved in these different fields of application.

International audience