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Gaussian Splatting Map Registration with Orthographic Bird's-Eye-View Renderings
No full textInternational audienceGaussian Splatting (GS) is a promising scene representation for visual localization and SLAM. Recent works have explored loop closure detection via Gaussian registration, improving map consistency and accuracy. However, achieving reliable registration given two GS representations from different acquisitions remains challenging. In this paper, we propose a complete pipeline to perform the matching and registration given two GS maps. The proposed method is grounded in generating orthographic bird's-eye views (BEVs) of optimized Gaussian models. The proposed approach leverages photometric and geometric information extracted directly from the GS to provide a trade-off of accuracy and invariance to different viewing changes (e.g., as types of GS maps, seasons, or illumination). Unlike existing 3D registration methods, which become inefficient as the number of Gaussians grows, our approach leverages 2D orthographic renders thus considerably reducing the registration complexity. Experiments on two public datasets demonstrate that our method achieves higher accuracy than several existing baselines, while also maintaining better registration results when dealing with GS maps learned by different techniques (e.g., 3DGS to LightGaussian), or GS maps presenting viewing changes such as varying illumination conditions.</div
Slanted and Colorful: Effects of Wordmark Logo Design on Brand Perceptions
No full textInternational audienc
Experimental investigation of the heating process of a small volume of ethanol under subcritical, critical and supercritical pressures
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L'accès à une alimentation satisfaisante sur le territoire de Montreuil en Seine-Saint-Denis
No full textInternational audienceLa question alimentaire sur les territoires croise d’un côté le développement de nombreuses initiatives relevant de systèmes alimentaires alternatifs (Amap, circuits-courts, coopératives de consommation, etc.) et de l’autre, une augmentation du nombre de personnes en situation de précarité alimentaire, associée à des préoccupations croissantes de santé publique (obésité, maladies cardio-vasculaires, dénutrition). Dans cette tension, les collectivités territoriales sont sollicitées pour soutenir des alternatives (des circuits-courts, des boucles alimentaires vertueuses, etc.) et pour lutter contre l’aggravation de laprécarité alimentaire. Elles sont, de fait, confrontées à des difficultés pour porter une politique alimentaire visant l’accessibilité de toutes et tous à une alimentation satisfaisante, qui soit de bonne qualité gustative, choisie, tout en assurant un revenu décent aux agriculteurs et en étant respectueuse de l’environnement. Dans ce contexte, nous étudions la stratégie alimentaire de la Ville de Montreuil, dans la banlieue est parisienne. Le territoire montreuillois se caractérise par un milieu urbain dense, une faible autonomie en matière de production agricole et une importante précarité alimentaire. Les enjeux agricoles et alimemtaires occupent une place particulière au sein d’un tissu associatif par ailleurs très dense. Ce chapitre examine les résultats de la recherche participa-tive « Construire un projet alimentaire citoyen sur un territoire urbain :initiatives pour une alimentation durable et accessible à Montreuil » (COPALIM). COPALIM s’appuie sur un partenariat entre une collectivité territoriale qui souhaite mettre en place une stratégie alimentaire sur le territoire, des acteurs issus de l’économie sociale et solidaire, des acteurs de l’accompagnement social et des laboratoires de recherche.La question de recherche a porté au départ sur la question de l’accès à une alimentation durable pour évoluer vers un questionnement sur l’accès à une alimentation satisfaisante dans un contexte marqué par une importante précarité alimentaire. La première partie de ce chapitre présente les enjeux théoriques de l’accès à l’alimentation durable et lescaractéristiques participatives de cette recherche. La seconde partie présente les résultats de l’enquête menée dans ce cadre en matière d’accès à l’alimentation des publics confrontés à de multiples fragilités et les réponses existantes à ces situations sur le territoire de Montreuil
Charles III (1543-1608) et la régence de Christine de Danemark (1545-1552) puis de Nicolas de Lorraine (1545-1559)
No full textThe efficacy of formaldehyde-free tannin resin in comparison with melamine-formaldehyde resin for enhancing the biological durability of ancient wooden copings
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616176/)International audienceThis study aimed to assess the efficacy of formaldehyde-free tannin-hexamine-boric acid resin, in comparison with melamine-formaldehyde resin, for enhancing the biological resistance of ancient oak wood (Quercus castaneifolia) copings against white rot fungus (Trametes versicolor), brown rot fungus (Coniophora puteana), and the underground termite (Reticulitermes flavipes). The wood specimens were impregnated with the resins through a full cell process, followed by drying according to a moisture-based schedule, curing of the resin at 103 ± 2 °C for 48 h, and eventually a 4-hour curing period at 120 °C. The weight percent gain (WPG) was notably higher for the samples impregnated with melamine-formaldehyde resin (15.5 %) compared to those impregnated by formaldehyde-free tannin-hexamine-boric acid resin (7.4 %). No significant discrepancies were observed in leaching resistance among the two resin types. The results revealed that the resins were more effective in enhancing the resistance of ancient wood to termites than to fungi
A programming language combining quantum and classical control
No full textThe two main notions of control in quantum programming languages are often referred to as "quantum" control and "classical" control. With the latter, the control flow is based on classical information, potentially resulting from a quantum measurement, and this paradigm is well-suited to mixed state quantum computation. Whereas with quantum control, we are primarily focused on pure quantum computation and there the "control" is based on superposition. The two paradigms have not mixed well traditionally and they are almost always treated separately. In this work, we show that the paradigms may be combined within the same system. The key ingredients for achieving this are: (1) syntactically: a modality for incorporating pure quantum types into a mixed state quantum type system; (2) operationally: an adaptation of the notion of "quantum configuration" from quantum lambda-calculi, where the quantum data is replaced with pure quantum primitives; (3) denotationally: suitable (sub)categories of Hilbert spaces, for pure computation and von Neumann algebras, for mixed state computation in the Heisenberg picture of quantum mechanics
Parameter-Free Predictive Control of PMSM Drives: An Incremental Ultra-Local Approach
No full textInternational audienc
Technologies, conflicts, and advancements in multi-objective optimization of thermal – daylight coupling and building energy consumption for flat skylights: A review
No full textInternational audienceFlat skylights, as key transparent envelope elements, offer significant potential for achieving healthy indoorenvironments and building sustainability but face the thermal-daylighting conflict that hinders comfort andimpacts building energy consumption. This review synthesizes evaluation systems, innovative technologies, coreconflicts, and development trends in optimizing the thermal-daylighting performance and energy efficiency offlat skylights. Key findings highlight the innovative advancements in multi-objective optimization (MOO)technologies and advanced skylight materials. However, the limitations, including the isolation of thermal anddaylighting comfort, along with deficiencies in static evaluation models and human-centered integration, stillremain. The review further assesses the potential challenges in resolving the conflicts. Conclusively, it underscoresthe urgent need to enhance MOO algorithms, dynamic environmental adaptability, and humancenteredfeedback design for the study in flat skylights. The insights aim to promote the transformation of flatskylights from static design to dynamic intelligent control for healthier and more sustainable buildings
Damping RF waves with low reflection in simulations of slab or curved magnetized plasma: parametrization, verification and implementation of Bermudez Perfectly Matched Layers.
No full textInternational audienceMost Radio-Frequency antenna simulations in magnetic fusion require emulating radiation at infinity at some boundaries of the simulation domain. To this end, the Perfectly Matched Layer (PML) technique amounts to stretching artificially the (real) spatial coordinates into the complex plane. Following reference [1], this contribution parametrizes, tests numerically and implements unbounded stretching functions, whose only numerical limitations arise from the PML discretization: refining the mesh can reduce the spurious reflections from the PML arbitrarily low, at the expense of a larger numerical cost. We tune the PML to ensure low wave reflection in a prescribed spectral range [kn,min, kn,max] in a direction n, with a minimal discretization (i.e. at a minimal computational cost). We extensively quantify the reflection coefficients using 1D Finite Element simulations. The minimal discretization for a regular mesh scales as kn,max/kn,min. We extend the PML formulation to a cylindrical geometry, where the wave eigenmodes involve Bessel functions. We implement slab radial and parallel Bermudez PMLs in realistic multi-2D RF simulations [2], to attenuate the propagative Slow Waves parasitically emitted by the ITER ICRF antenna into a tenuous scrape-off layer