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IA : bienfait commun ou piège capitaliste ?
No full textInternational audiencen recent months, artificial intelligence has been making the headlines on a regular basis: virtual assistants, realistic image generation, immersive worlds... As the biggest technology companies get to grips with the field, what can we (dis)expect from this progress?White Mirror, the fantasy of utopiaThe Meta-verse, AI and other recent tools are gradually opening up a new perspective: "The most beautiful utopias seem within reach". From the creation of virtual assistants to the generation of realistic images, from augmented reality to the creation of content by AI in virtual reality, discover the technological advances that promise a radiant future by making our lives easier, while allowing us to project ourselves into many immersive universes.Black Mirror, the reality of dystopiaHowever, behind these promises lie profound questions about our relationship with technology and the limits of these solutions. As advances in artificial intelligence multiply, we are faced with complex ethical dilemmas. What lies behind the scenes of immersive worlds and virtual assistants? Are we ready to face up to the consequences of our growing dependence on this type of technology? These reflections, inspired by the 'Black Mirror' series, invite us to question our relationship with technology and to envisage a future where the boundaries between reality and fiction become blurred.Ces derniers mois, l’intelligence artificielle fait régulièrement les gros titres : assistants virtuels, génération d’images réalistes, univers immersifs… À l’heure où les plus grandes entreprises de la technologie s’emparent du domaine, que pouvons nous (dés)espérer de ces progrès ?White Mirror, le fantasme de l’utopieLe Méta-vers, l’IA et autres outils récent nous ouvrent peu à peu une perspective : « Les plus belles utopies semblent à portée de main ». De la création d’assistants virtuels à la génération d’images réalistes, de la réalité augmentée à la création de contenu par de l’IA en réalité virtuelle, découvrez les avancées technologiques qui promettent un avenir radieux en nous facilitant la vie, tout en nous permettant de nous projeter dans de nombreux univers immersifs.Black Mirror, la réalité de la dystopieCependant derrière ces promesses se cachent aussi des questionnements profonds sur notre relation à la technologie et les limites de ces solutions. Alors que les avancées de l’intelligence artificielle se multiplient, nous nous retrouvons face à des dilemmes éthiques complexes. Que se cache-t-il derrière les coulisses des univers immersifs et des assistants virtuels ? Sommes-nous prêts à faire face aux conséquences de notre dépendance croissante à ce type de technologie ? Ces réflexions, inspirées de la série « Black Mirror », nous invitent à remettre en question notre rapport à la technologie et à envisager un avenir où les frontières entre la réalité et la fiction s’estompent
PPU, PAE : quel rôle des outils d’urbanisme dans le développement urbain durable au Québec ?
No full textInternational audienceThis contribution examines the role of two regulatory urban planning tools in the sustainable urban development sector in Quebec (Canada). The analysis of a corpus of PPU and PAE and interviews conducted in 2021-2022 with Quebec practitioners demonstrate a political will to regain control over real estate development and highlights its main limitations: lack of precision in their prescriptions, poor transposition into enforceable regulations, complexity of operational and legal implementation, and lack of anticipation of land dynamics. PPU and PAE remain the tools of a negotiated sustainable urbanism, admittedly coercive, but never really restrictive.Cette contribution étudie le rôle de deux outils d’urbanisme dans la fabrique urbaine durable au Québec. L’analyse d’un corpus de programmes particuliers d’urbanisme (PPU – devenus les plans particuliers d’urbanisme en juin 2023), de plans d’aménagement d’ensemble (PAE) et d’entretiens menés en 2021-2022 auprès de praticiens québécois témoigne d’une volonté politique de reprise de contrôle sur le développement immobilier et souligne ses principales limites : manque de précision des prescriptions, faible retranscription de celles-ci dans le règlement opposable, complexité de mise en œuvre opérationnelle et juridique ou encore manque d’anticipation des dynamiques foncières. PPU et PAE restent les outils d’un urbanisme durable négocié, certes formalisateur, mais jamais réellement contraignant
The local linear functional kNN estimator of the conditional expectile: uniform consistency in number of neighbors
No full textInternational audienceThe main purpose of the present paper is to investigate the problem of the nonparametric estimation of the expectile regression in which the response variable is scalar while the covariate is a random function. More precisely, an estimator is constructed by using the local linear k Nearest Neighbor procedures (kNN). The main contribution of this study is the establishment of the Uniform consistency in Number of Neighbors of the constructed estimators. These results are established under fairly general structural conditions on the classes of functions and the underlying models. The usefulness of our result for the smoothing parameter automatic selection is discussed. Some simulation studies are carried out to show the finite sample performances of the kNN estimator. The theoretical uniform consistency results, established in this paper, are (or will be) key tools for many further developments in functional data analysis
PLM data transformation: A mesoscopic scale perspective and an industrial case study
No full textInternational audienceStructured enterprise information systems such as Enterprise Resources Planning (ERP) and Product Lifecycle Management (PLM) have reached a maturity plateau and are storing up to hundreds of millions of objects and links. Such data is crucial for enterprise processes and operations. They are frequently the target of data transformation such as migration to a new data system, re-organisation according to new business paradigms, cleansing, purge and archive, etc. To make data transformation manageable, iterative, and achievable, it requires a divide and conquer strategy therefore producing loosely coupled data packages. Most data migration methods recommend divide and conquer strategy but do not explain how to produce these loosely coupled data packages. This paper outlines there exist two different approaches relying on a wide range of algorithms: clustering and community detection. Also, data package must be PLM business meaningful and fit into a mesoscopic scale to provide operational and achievable options for data transformation. Finally, a PLM specific algorithm is proposed for pre-processing data before clustering. A multi-pass tooled-up method able to combine and sequence data clustering approaches/algorithms has been developed for this purpose: Data Systemizer (D6). Using graph-based clustering metrics will help to assess the benefit of multi-pass data clustering approach and provide some principles to select right clustering approaches/algorithms chain
Quand les PLU(i) régulent la pluie : évaluation du potentiel des Plans Locaux d'Urbanisme pour intégrer la gestion des eaux pluviales à la source : le cas de Nantes Métropole
No full textDeveloping planning scenarios at the scale of a conurbation is a perilous exercise. Most studies on nature-based solutions use simplistic scenarios where a single type of solution is disseminated at the scale of the area studied or several solutions are combined, according to loose rules (e.g.: VEGDUD1, VURCA2 projects). The studies that use realistic scenarios are generally at the neighbourhood level, based on planned development projects (N4C3, URBiNAT4 projects). Larger-scale and longer-term development scenarios (around 10 years) require a methodology that allows for the dissemination of adaptation solutions in a (semi-)automated way while taking into account a minimum of constraints related to the territory to ensure their realism (de Gouvello et al, 2015). Moreover, in the framework of a prospective approach, a set of scenarios covering the field of possibilities is to be favored. Urban planning documents are therefore of interest because they are sufficiently restrictive to limit the scenarios to the territory's adaptation strategy, while leaving a certain amount of freedom to use different solutions, to meet the territory's challenges. Moreover, zoning can allow a certain degree of automation on a large scale. Once the scenario(s) has been developed, translating them into parameters adapted to the TEB-Hydro model still presents a challenge and is then potentially, again, a set of several configurations per scenario. The objective of this thesis work is therefore to develop a methodology for constructing development scenarios in order to evaluate community adaptation strategies to improve thermal comfort and stormwater management.La gestion des eaux pluviales à la source vise en priorité à infiltrer l’eau de pluie là où elle tombe. Lorsque l’infiltration est impossible, elle privilégie le stockage temporaire et une restitution régulée dans le réseau d’assainissement afin d’éviter toute surcharge. Cette approche, notamment via les solutions fondées sur la nature, constitue une stratégie clé d’adaptation au changement climatique et de lutte contre l’imperméabilisation croissante des sols, qui limite l’infiltration, accentue le ruissellement et réduit la recharge des nappes phréatiques. Les Plans Locaux d’Urbanisme (PLU(i)), qui encadrent l’occupation des sols, peuvent traduire ces principes en règles opérationnelles. Celles-ci peuvent imposer ou encourager l’infiltration, le stockage, la dépollution, le maintien des surfaces végétalisées ou encore la désimperméabilisation des sols. Les collectivités disposent de plusieurs leviers pour formuler les règles d’urbanisme, variant entre approches qualitatives ou quantitatives et degrés normatifs (permissifs ou impératifs). Toutefois, il n’existe pas de méthode formelle pour évaluer la traduction efficace de la gestion à la source en règles opérationnelles et anticiper leurs effets, même si le droit impose des évaluations des PLU(i) en matière de protection de l’environnement. Cette thèse transdisciplinaire explore cette problématique à travers l’étude du Plan Local d’Urbanisme métropolitain (PLUm) de Nantes Métropole. Elle repose sur une approche mixte combinant ateliers participatifs, entretiens, analyses de contenu, étude systématique d’archives et modélisation spatiale SIG. Sur le plan théorique, la thèse éclaire le processus de création et d’application des règles d’urbanisme. Elle met en évidence le rôle des règles quantitatives, qui fixent des critères précis garantissant clarté et prévisibilité, et des règles qualitatives, plus souples, qui offrent une marge d’adaptation contextuelle mais introduisent une variabilité d’interprétation. Pour limiter ces écarts, le PLUm de Nantes Métropole se distingue par une rigueur réglementaire encadrant cette flexibilité afin d’assurer une gestion minimale des eaux pluviales sur l’ensemble du territoire. Néanmoins, cette régulation stricte ne supprime pas toutes les incertitudes : la mise en œuvre des solutions dépend fortement des contextes locaux (conditions des terrains, ajustements politiques ou financiers, visions urbanistiques...) confirmant la nature indéterministe des règles. Sur le plan méthodologique et opérationnel, la thèse développe une méthode d’évaluation ex ante pour analyser le potentiel réglementaire des PLU(i) vis-à-vis de 23 solutions de gestion des eaux pluviales. Selon cette méthode, le PLUm de Nantes Métropole offre un cadre favorable à de nombreuses solutions, même si certaines d'entre elles bénéficient d’un potentiel plus limité. Les résultats confirment l’intérêt d’une évaluation préalable des règles, car leur combinaison peut générer des effets spatiaux cumulatifs inattendus. Enfin, des pistes d’amélioration de la méthode d’évaluation sont proposées. Celle-ci pourrait également être transposable à d’autres thématiques et territoires
First co-culture of human dural fibroblasts and adipose stem cells for dura mater tissue-engineering
No full textInternational audienceIntroductionThe dura mater, the meninges’ outermost layer, acts as a semi-rigid barrier between the central nervous system and bone tissues [1]. Its limited healing ability and tendency to form scar tissue can lead to complications after neurosurgery and dural resection. Advancements in dural tissue engineering could enhance our understanding of this interface and help create in vitro models and implantable scaffolds for dura mater repair. One challenge is to develop a co-culture model using human dural fibroblasts (HDufs) and adipose-derived stem cells (ASC52telo) differentiated into osteoblasts, aiming to mimic natural tissue environments and study cell interactions. Here, we present the phenotype analysis results for HDufs and ASC52telo after up to one month of co-culture.MethodsTwo co-culture methods, indirect (separate compartments) and direct (mixed), were conducted using HDufs and ASC52telo. Initially, cells were cultured in an optimized proliferation medium for one week. Then, a three-week period followed with or without osteogenic factors (dexamethasone, ascorbic acid, and beta-glycerophosphate). To assess the effects of co-culture methods and osteogenic stimulation on the behavior of HDufs and ASC52telo, qPCR, immuno-fluorescence, ALP staining, and alizarin red staining were performed at 14 and 28 days. Monoculture controls were conducted to validate the study.Results and discussionThe results revealed increased expression of osteogenic genes and bone biomarkers during co-culture, indicating stem cell maturation into osteoblasts even without differentiation factors, suggesting a beneficial impact of HDufs interaction on this process. Regarding HDufs' functionality in long-term co-culture, they exhibited a notable phenotype change: increased expression of dura mater periosteal layer-related markers and Crapb2 decrease, specific of the dural border cell layer [2] (native dura deepest layer). The dural fibroblast marker FxyD5 was expressed all along till the co-culture end. ConclusionLong-term co-culture of HDufs and ASC52telo proved stable, ensuring survival and functionality of both cell types. The synergy between them facilitated stem cell differentiation into mature osteoblasts while inducing phenotypic changes in HDufs resembling native tissue. These findings support the potential of this co-culture model for in vitro dura mater studies and as a substitute testing model for in vivo purposes. Next, we plan to validate these results with 3D scaffold co-culture.References1.Vandenabeele et al, J Anat, 189:417–30, 1996. 2.Farmer and al.,Nat Commun, 12:4797, 202
Numérique humanitaire et protection des données : colonialité, souveraineté et dignité
No full textThe exploitation of data by multinationals, cyber-attacks, the proliferation of disinformation operations - today's digital environment is shaken by a growing number of tensions which do not spare humanitarian aid, especially as the sector has been digitalising its operations for the last ten years. NGOs have gradually adopted a series of digital tools, including data processing software, drones, biometric devices and conversational agents, blockchains and artificial intelligence. These organisations are therefore particularly vulnerable to the excesses of surveillance capitalism and the geopolitical tensions running through the digital space. The beneficiaries are the first victims. And this brings us to the following contradiction: humanitarians - actors committed to protecting the victims of crises - have adopted digital tools that can infringe on their privacy, or even put them in danger. The aim of this thesis is to attempt to understand the nature of this paradox, which requires us to examine the different dynamics and tensions that accompany the digitalisation of the humanitarian sector. First of all, the digitisation of humanitarian aid stems from the quantification of aid, which is itself linked to donors' demands to improve the accountability of NGOs and the traceability of funds. The digitisation of the humanitarian sector is also part of a more general move by the international aid community towards the private sector. This movement is accompanied by the spread of an innovation imperative and by a solution-oriented vision of new technologies. But for researchers such as Kristin Sandvik and Mirca Madianou, this innovation imperative is more akin to a form of "techno-colonialism". The dynamics of power resulting from colonial legacies contribute to the construction of beneficiaries as potential passive 'subjects' of experimentation, at the expense of respect for their privacy. The crises are also characterised by exceptional regimes that facilitate the experimentation of technologies in a context of suspension of the legal framework in force. However, this picture can be nuanced. On a more general scale, we are witnessing a movement to regulate innovation, reflected in a series of laws such as the Data Protection Regulation (RGPD), the Digital Markets Act, the Artificial Intelligence Act, etc. These laws also affect humanitarian aid. Part of our thesis is therefore devoted to the work of data protection officers working in humanitarian NGOs. Part of our thesis is therefore devoted to the work of data protection officers attached to humanitarian NGOs. But we will also see that the latter is based on a compliance approach that is not without its limits. We will then look at a second dynamic which is contributing to increasing the risks associated with the digitisation of the international solidarity sector. In short, it concerns the shrinking of humanitarian space, linked to the exercise of state sovereignty, and its translation into informational and digital space. Firstly, we will look at how data exchanges between NGOs and host countries are perceived and regulated. These exchanges can be seen as legitimate, but also as a risk factor, particularly if they are associated with forms of state violence and the criminalisation of aid beneficiaries. Secondly, we will take into account the fact that the digitisation of our societies also accompanies and reinforces a long-term phenomenon of recompositions of sovereignty. This phenomenon is also linked to the entry onto the scene of a series of non-state actors, obviously companies such as the GAFAMs, but also other more informal groups such as hackers. The involvement of cybercombatants in contemporary conflicts is part of a long movement to challenge the State's monopoly on violence as a result of the proliferation of intra-State conflicts - against terrorist groups, for example.L’espace numérique contemporain est agité par un nombre croissant de tensions qui n’épargnent pas les humanitaires, d’autant que le secteur a entamé depuis une dizaine d’années une numérisation de ses opérations. Ces organisations sont donc particulièrement vulnérables aux dérives du capitalisme de surveillance et des tensions géopolitiques traversant l’espace numérique. Les bénéficiaires en sont les premières victimes. Et l’on en vient à la contradiction suivante : les humanitaires — des acteurs engagés dans la protection de victimes de crises — ont adopté des outils numériques qui peuvent porter atteinte à leur vie privée, voire les mettre en danger. L’objectif de cette thèse a été de tenter de comprendre la nature de ce paradoxe, ce qui nécessite de creuser les différentes dynamiques accompagnant la numérisation de l’humanitaire. Un premier type de dynamique résulte de legs coloniaux et participe à la construction des bénéficiaires d’ONG comme de potentiels « sujet » passifs d’expérimentation numérique. Toutefois, on assiste à une échelle plus générale à un mouvement de régulation de l’innovation, qui se traduit par une série de lois comme le règlement sur la protection des données (RGPD). Une partie de notre thèse est donc consacrée au travail des délégués à la protection des données d’ONG comme régulation des expérimentations numériques menées dans des crises. Puis, on a pu étudier une deuxième dynamique contribuant à renforcer les risques liés à la numérisation des ONG. Elle concerne le resserrement de l’espace humanitaire, en lien avec l’exercice des souverainetés étatiques, et sa traduction sur le plan informationnel et numérique. On est revenue sur les façons de protéger les bénéficiaires contre ces menaces. Mais les ONG courent le risque de réduire ces derniers à être de simples « objets de protection » et des victimes passives. Mais on verra que les humanitaires s’efforcent aussi de prendre en compte leurs droits garantis par le RGPD et de défendre leur dignité
Routing Optimization Based on Distributed Intelligent Network Softwarization for the Internet of Things
No full textInternational audienceThe Internet of Things (IoT) establishes connectivity between billions of heterogeneous devices that provide a variety of essential everyday services. The IoT faces several challenges, including energy efficiency and scalability, that require consideration of enabling technologies such as network softwarization. This technology is an appropriate solution for IoT, leveraging Software Defined Networking (SDN) and Network Function Virtualization (NFV) as two main techniques, especially when combined with Machine Learning (ML). Although many efforts have been made to optimize routing in softwarized IoT, the existing solutions do not take advantage of distributed intelligence. In this paper, we propose to optimize routing in softwarized IoT networks using Federated Deep Reinforcement Learning (FDRL), where distributed network softwarization and intelligence (i.e., FDRL) join forces to improve routing in constrained IoT networks. Our proposal introduces the combination of two novelties (i.e., distributed controller design and intelligent routing) to meet the IoT requirements (mainly performance and energy efficiency). The simulation results confirm the effectiveness of our proposal compared to the conventional counterparts
Editorial on Oxidation of Novel Metallic Materials (Intermetallics, MMCs, HEAs…)
No full textInternational audienceOver the past ten years, new methodologies have emerged that have markedly accelerated the development of new alloys. In particular, the utilisation of rapid high-throughput techniques and novel numerical alloy design approaches now enables the development of alloys with multiple optimised characteristics for a specific application. These characteristics may concern thermomechanical properties (such as strength and creep resistance), or other properties (such as density or cost), and may also relate to the ability of the alloy to achieve good behaviour in a corrosive environment at high temperature. In this context, the emergence of high-entropy alloys (HEAs) and concentrated complex alloys (CCAs), comprising four to six concentrated elements, has led to the emergence of new fields of research. However, in this new paradigm of ‘combinatorial metallurgy’, there is also an increased scope for innovation in the case of ‘conventional’ steels or nickel-based alloys or light alloys, since they may contain an even greater number of alloying elements.[...
Linear contractions effect on the propagation of hydrogen and methane flames in large scale pipeline
No full textInternational audienceThe motivation of gas industries to switch from fossil fuels to hydrogen raise questions related to thesafety of operations. One of the scenario of interest is related to a flame propagation in a long pipe.While most of flame propagation analysis in pipes are carried in straight configuration with differentsizes, the very few studies on the influence of single elements are carried at small scale.In order to develop the knowledge on the piping geometrical effect on flame acceleration, experimentswere performed in a 250mm diameter and 24m long straight pipe, closed at ignition and open to theatmosphere at the other end. The single elements tested here are two soft and sharp section changes.All single elements are located 16m from ignition in order to get a well-developed flame front whenreaching the single element. Two flammable mixtures were tested that are stoichiometric methaneairand lean hydrogen-air, meaning two slow and fast nominal flame velocities.It appears that the contraction promotes flame acceleration for both mixtures, but in a more importantmanner in the case of hydrogen flame compared to methane. The assumption of flame surfaceextension due to radial velocity gradient is put forward to explain this acceleration