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Inference Problem in Probabilistic Multi-Label Classification
No full textInternational audienceIn multi-label classification, each instance can belong to multiple labels simultaneously. Different evaluation criteria have been proposed for comparing ground-truth label sets and predictions. Probabilistic multi-label classifiers offer a unique advantage by allowing optimization of different criteria at prediction time, but they have been relatively underexplored due to a shortage of insights into inference complexity and evaluation criteria. To shrink this gap, we present a generic approach for developing polynomial-time inference algorithms for a family of criteria and discuss the potential (dis)advantages of some commonly used criteria. Finally, we envision future work aimed at providing a comprehensive understanding of inference complexity and criteria selection.</div
Low frequency absorption by 3D printed materials having highly tortuous labyrinthine slits in impermeable or microporous skeletons
No full textInternational audienceThe low frequency peaks in the absorption spectra of layers of conventional porous materials correspond to quarter wavelength resonances and the peak frequencies are determined essentially by layer thickness. If the layer cannot be made thicker, the frequency of the peak can be lowered by increasing the tortuosity of the material. Modern additive manufacturing technologies enable exploration of pore network designs that have high tortuosity. This paper reports analytical models for pore structures consisting of geometrically complex labyrinthine networks of narrow slits resembling Greek meander patterns. These networks offer extremely high tortuosity in a non-porous solid skeleton. However, additional enhancement of the low frequency performance results from exploiting the dual porosity pressure diffusion effect by making the skeleton microporous with a significantly lower permeability than the tortuous network of slits. Analytical predictions are in good agreement with measurements made on two samples with the same tortuous slit pattern, but one has an impermeable skeleton 3D printed from a photopolymer resin and the other has a microporous skeleton 3D printed from a gypsum powder
Research progress in microalgae nutrients: emerging extraction and purification technologies, digestive behavior, and potential effects on human gut
No full textInternational audienceMicroalgae contain a diverse range of high-value compounds that can be utilized directly or fractionated to obtain components with even greater value-added potential. With the use of microalgae for food and medical purposes, there is a growing interest in their digestive properties and impact on human gut health. The extraction, separation, and purification of these components are key processes in the industrial application of microalgae. Innovative technologies used to extract and purify microalgal high-added-value compounds are key for their efficient utilization and evaluation. This review’s comprehensive literature review was performed to highlight the main high-added-value microalgal components. The technologies for obtaining bioactive compounds from microalgae are being developed rapidly, various innovative, efficient, green separation and purification technologies are emerging, thus helping in the scaling-up and subsequent commercialization of microalgae products. Finally, the digestive behavior of microalgae nutrients and their health effects on the human gut microbiota were discussed. Microalgal nutrients exhibit favorable digestive properties and certain components have been shown to benefit gut microbes. The reality that must be faced is that multiple processes are still required for microalgae raw materials to final usable products, involving energy, time consumption and loss of ingredients, which still face challenges
Processing of Food Products and Wastes with High Voltage Electrical Discharges
No full textInternational audienceProcessing of Food Products and Wastes with High Voltage Electrical Discharges presents basic knowledge on HVED technology, focusing on the mechanisms, related phenomena and effects, equipment design, methods and examples of application. Divided in three parts, the book covers the advantages and restrictions of HVED technology for the treatment of numerous specific food products, by-products and wastes, such as grape, oilseed, citrus by-products and wastes, lignocellulosic and algal biomass, meat and bacterias. This book act as a comprehensive resource for researchers to be able to use the data for the dimensioning of HVED and processing equipment and finding the optimal treatment parameters
Electrical discharges in water: prebreakdown and breakdown phases
No full textInternational audienceBasic mechanisms of electrical discharges in water and water/solid mixtures are described, including prebreakdown and breakdown phases, streamer initiation and propagation, electrical arc developing, bubble formation and growth, and shock wave phenomena. Aqueous medium characteristics and process parameters influencing the breakdown voltage and current, electrode temperature, bubbles size and internal pressure, velocity of streamer propagation, and shock wave pressure are analyzed. Relations for the modeling of phenomena induced by the electrical discharges in water are presented. This permits to better understand and predict the effects of electrical discharges on the fragmentation of biosolids and food mixtures, and extraction of valuable compounds
Mechanical and biological characterization of electrospun scaffolds as biomimetic dural substitutes
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Substituted Oligosaccharides as Protein Mimics: Deep Learning Free Energy Landscapes
No full textInternational audienceProtein-protein complexes power the majority of cellular processes. Interfering with the formation of such complexes using well-designed mimics is a difficult, yet actively pursued, research endeavor. Due to the limited availability of results on the conformational preferences of oligosaccharides compared to polypeptides, the former have been much less explored than the latter as protein mimics, despite interesting ADMET characteristics.In this work, the conformational landscapes of a series of 956 substituted glucopyranose oligomers of lengths 3 to 12 designed as protein interface mimics are revealed using microsecond-timescale, enhanced-sampling molecular dynamics simulations. Deep convolutional networks are trained on these large conformational ensembles, to predict the stability of longer oligosaccharide structures from those of their constituent trimer motifs. Deep generative adversarial networks are then designed to suggest plausible conformations for oligosaccharide mimics of arbitrary length and substituent sequences, that can subsequently be used as input to docking simulations. Analyzing the performance of the neural networks also yields insights into the intricate collective effects that dominate oligosaccharide conformational dynamics.</p
Intégrité de la perception coopérative pour les véhicules intelligents
No full textIn order to navigate safely and comfortably, intelligent vehicles require highly reliable perception of their environment. Since on-board sensors are necessarily limited in range, and because their field of view can be obscured, an emerging solution is cooperative perception: vehicles share their perception with other vehicles via wireless communication. Intelligent vehicles can thus communicate complex information over long distances. They see further and more completely than their sensors could ever allow. However, information from external sources must be treated with caution, as misleading information can lead to a dangerous situation. The sources of degradation of this information's "integrity" in the cooperative system must therefore be kept to a minimum. In this thesis, we study these sources and propose suitable methods for managing them and avoiding their propagation. Our work focuses in particular on the fusion of tracked objects, the representation of areas covered by perception systems and the management of trust attributable to other communicating agents. In order to avoid underestimating the uncertainty linked to the state of perceived objects, we are studying data fusion filters capable of handling the information loops induced by exchanges. Our results on simulated data show that a split covariance intersection filter is a suitable method for this problem. Coupled with the parameter-tuning methodology we propose, this method also appears to outperform more conventional methods. Next, we introduce a formalism for representing the areas covered by each sensor and the areas seen as free, in order to better merge the detected objects. This is the concept of evidential detectability grids, based on the theory of belief functions. These detectability grids make it possible to merge several points of view to obtain a global representation of the environment, while explicitly managing uncertainties. Finally, we propose a method for each vehicle to elaborate a trust index on the other cooperative agents. It is based on an evidential tree combining several pieces of evidence, such as the consistency and concordance of the information received. The confidence index is then used to ensure that each vehicle reliably combines locally perceived information with that transmitted by other vehicles. The performance of the global cooperative perception method is evaluated on real data obtained using three experimental vehicles equipped with omnidirectional LiDAR sensors. The corresponding data sets are made available to the scientific community.Afin de naviguer de manière sure et confortable, les véhicules intelligents nécessitent une perception très fiable de leur environnement d'évolution. Les capteurs embarqués étant nécessairement limités en portée et leur champ de vue pouvant faire l'objet d'occultations, une solution émergente est la perception coopérative : les véhicules partagent leur perception avec les autres véhicules par des moyens de communication sans fil. Les véhicules intelligents peuvent ainsi communiquer des informations complexes à travers de longues distances. Ils voient plus loin et de manière plus complète que ce que leurs capteurs leur permettent. Cependant, les informations provenant d'une source extérieure doivent être considérées avec prudence car une perception trompeuse peut entraîner une situation dangereuse. Il convient donc de limiter au maximum les sources de dégradation de l'intégrité de l'information dans le système coopératif. Dans cette thèse, nous étudions ces sources et nous proposons des méthodes adaptées pour les gérer et éviter leur propagation. Nos travaux se concentrent en particulier sur la fusion d'objets pistés, la représentation des zones couvertes par les systèmes de perception et la gestion de la confiance imputable aux autres agents communicants. Afin d'éviter de sous-estimer l'incertitude liée à l'état des objets perçus, nous étudions des filtres de fusion de données capables de gérer les boucles d'information, induites par les échanges. Nos résultats sur données simulées montrent qu'un filtre a intersection de covariance partitionnée est une méthode adaptée à ce problème. Couplée à la méthodologie de réglage des paramètres que nous proposons, cette méthode peut également être plus performante que d'autres plus classiques. Ensuite, nous présentons un formalisme permettant de représenter les zones couvertes par chaque capteur et les zones vues comme libres afin de mieux fusionner les objets détectés. C'est le concept de grilles de détectabilité évidentielles, basé sur la théorie des fonctions de croyance. Ces grilles de détectabilité permettent de fusionner plusieurs points de vue pour obtenir une représentation globale de l'environnement tout en gérant explicitement les incertitudes. Finalement, nous proposons une méthode pour que chaque véhicule élabore un indice de confiance sur les autres agents coopératifs. Elle se base sur un arbre évidentiel combinant plusieurs éléments de preuve comme la cohérence et la concordance des informations reçues. L'indice de confiance est ensuite utilisé pour que chaque véhicule combine de façon fiable les informations perçues localement avec celles transmises par les autres véhicules. Les performances de la méthode globale de perception coopérative sont évaluées sur des données réelles obtenues à l'aide de trois véhicules expérimentaux équipés de capteurs LiDAR omnidirectionnels. Les jeux de données correspondants sont rendus publics à la communauté scientifique
Du soin technologique : enjeux épistémologiques et empiriques des modes d’intrication entre technique(s) et soin(s) dans la médecine contemporaine: Introduction - Qu’est-ce qu’un soin technologique ?
No full textWhat is Technological Care? — Why talk about "technological care"? How does this concept highlight the existence of irrefutable modes of entanglement between care and technique or technology? How can such modes of existence be analysed? While a number of recent studies in the anthropology of science and health have contributed to the deconstruction of this opposition between care and cure, research in the philosophy of medicine and the ethics of care is largely lacking on this subject. This deep-rooted tension between care and cure is indicative of a persistent contradiction between care and technique, which is not self evident. This issue aims to fill this gap in the literature, both conceptually and empirically, with a practical approach to philosophical reflection calling for the (necessary) crossing of expertise.Pourquoi parler de « soin technologique » ? En quoi ce concept permet-il de souligner l’existence de modes d’intrication, irréfutables, entre soin et technique ou technologie ? Comment analyser de tels modes d’existence ? Si de nombreux récents travaux d’anthropologie des sciences et de la santé ont participé à déconstruire cette opposition entre care et cure, les philosophes de la médecine et éthiciens du care sont majoritairement en reste sur ce sujet. Cette tension ancrée entre le care et le cure est pourtant révélatrice d’une contradiction, persistante, entre soin et technique, qui ne va pas de soi. Ce dossier vise donc à combler, conceptuellement et empiriquement, ce manque de littérature, dans une démarche de philosophie empirique qui en appelle au nécessaire croisement des expertises
Belief Functions on the Real Line defined by Transformed Gaussian Random Fuzzy Numbers
No full textInternational audienceThe recently introduced theory of epistemic random fuzzy sets extends both Dempster-Shafer and possibility theories, by allowing the representation of partially reliable and fuzzy evidence. Within this formalism, we study transformations of random fuzzy sets by one-to-one mappings, and show that such transformations commute with combination. We apply this result to define parameterized models of random fuzzy numbers, which generalize Gaussian random fuzzy numbers and allow us to construct easily combinable belief functions on a real interval. We apply this idea to the prediction of proportions