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MMC-Autotransformer : Impact of the Control on the Design and Efficiency
No full textInternational audienceTo increase flexibility and reliability of HVDC links and MTDC, it is likely that DC-DC converter will be employed. This paper specifically focuses on the DC-Auto-transformer. This study investigates its performance in relation to its parameters including: AC voltages, frequency and waveform characteristics. The analysis presented in this paper demonstrates that increasing the AC voltage within the converter reduces losses and minimizes capacitor size requirements. While, increasing the frequency reduces the losses as well as required size of capacitors. Furthermore, the results indicate that adopting a trapezoidal waveform improves both efficiency and capacitor size
A unified Eshelbian-like determination of defect driving forces
No full textInternational audienceWithin the framework of Continuum Mechanics, we present a unified theoretical approach todescribe the onset and propagation of defects in solid materials. In this context, the term defectencompasses both changes in the material’s topology—such as fracture propagation, rotation, andvolumetric expansion of inclusions or voids [1]—and material inhomogeneities, referring to spatialvariations in the material properties of the body [2, 3]. We characterize the kinematics of a defect by defining its mode of propagation. Following the principles of Eshelbian Mechanics [2, 3], we compute the associatedenergy release rate or driving force. Furthermore, we distinguish the contributions of thisdriving force by identifying their specific roles in defect propagation—whether purely mechanical,topological, or arising from inhomogeneities in constitutive parameters [2, 3].To illustrate the proposed procedure more clearly, we analyze several prototypical examples fromthe literature, contextualized within our framework [4]. Finally, we compare the obtained resultswith those derived from variational approaches based on conservation laws [1, 5].References[1] Knowles, J. K., Sternberg, E. “On a class of conservation laws in linearized and487finiteelastostatics”. Arch. Rat. Mech. Anal. 44(3):187–211 (1972)[2] Maugin, G. A. “Configurational Forces. Thermomechanics, Physics, Mathematics, and Numerics”CRC Press, 2016.[3] Gurtin, M. E. “Configurational forces as basic concepts of continuum physics”. Vol. 137.493.Springer Science & Business Media, 1999.[4] S. Di Stefano, C. Binetti, G. Puglisi, S. Giordano. “A unified Eshelby-like approach to defectpropagation”. In preparation.[5] Podio-Guidugli, P. “Configurational balances via variational arguments”. Interface FreeBound 3, 323–332. (2001
Jeanne Durieux: Tricks and Turns of the Imagination
No full textInternational audienceWhy is it that certain things, which take us away from our main research, echo inside us so intensely? Some sort of strong desire … Is it because of our own state at the moment we encounter these things? The fact is, I never could have imagined at the time, that the path I was heading down, week after week, would lead me into strange lands, bringing me face-to-face with people who, in one way or another, had encountered Jeanne Durieux, known as Jeanne Labroche. This woman – daughter of a Hungarian father and Spanish mother, haunted by political oppression, a self-taught ethnologist, a travel photographer, selling her photos and articles to armchair journalists who signed them in her stead – had all the makings of a book dedicated just to her. Bringing together the necessary elements, that had been dispersed over time, was not an easy feat. But one encounter always leads to another; and that’s how narratives and stories are made
Lithium in Portland cement clinker: absence of evidence is not evidence of absence
No full textInternational audienceLithium (Li) is a challenging element to analyse in mineral matrixes. The very low energy (54 eV) of its X-ray emission line makes it almost impossible to analyse by common methods such as energy dispersive spectroscopy. Hence, its localisation within cementitious phases is poorly known. Based on glow-discharge mass spectrometry and time-of-flight secondary ion mass spectrometry, the present paper shows for the first time the repartition of Li at the scale of a microstructure of clinker with a 200 nm lateral resolution. Li is correlated to both Al and Fe in the interstitial phase, but also to Mg in periclase
Machine learning and deep learning applications in the automotive manufacturing industry: A systematic literature review and industry insights
No full textInternational audienceIn the context of the automotive manufacturing industry, complexity and the extensive data generated during production pose significant challenges. With ongoing technological advancements, effectively harnessing and analyzing this data has become increasingly critical. Machine learning (ML) and deep learning (DL) have emerged as powerful tools to manage complexity and leverage data for enhanced decision-making and process optimization. This systematic literature review examines the application of ML and DL in automotive manufacturing, focusing on application domains, ML/DL model mapping, current trends, and effective implementation practices. Out of 2786 articles, 257 were analyzed, revealing key research areas: equipment optimization (31%), quality enhancement (26%), supply chain optimization (21%), and production efficiency (17%). Energy management was notably underrepresented (4%), indicating a significant opportunity for advancing energy efficiency and decarbonization efforts. Additionally, the review highlighted significant challenges in data management, including data quality, integration, and interoperability issues, which critically affect the successful deployment of ML and DL technologies. Insights from the review were shared with senior management at Toyota Motor Manufacturing France, aligning closely with their strategic vision for digital transformation. Successful implementation of ML and DL hinges on three essential pillars: standardization of manufacturing processes and data, robust IoT and big data infrastructure, and comprehensive human resource development. Embracing these pillars is crucial to navigating complexity, realizing AI’s full potential, and advancing efficiency, sustainability, and innovation in automotive manufacturing
Euclid: Early Release Observations -- Globular clusters in the Fornax galaxy cluster, from dwarf galaxies to the intracluster field
No full textInternational audienceWe present an analysis of Euclid observations of a 0.5 deg field in the central region of the Fornax galaxy cluster that were acquired during the performance verification phase. With these data, we investigate the potential of Euclid for identifying GCs at 20 Mpc, and validate the search methods using artificial GCs and known GCs within the field from the literature. Our analysis of artificial GCs injected into the data shows that Euclid's data in band is 80% complete at about mag ( mag), and resolves GCs as small as pc. In the band, we detect more than 95% of the known GCs from previous spectroscopic surveys and GC candidates of the ACS Fornax Cluster Survey, of which more than 80% are resolved. We identify more than 5000 new GC candidates within the field of view down to mag, about 1.5 mag fainter than the typical GC luminosity function turn-over magnitude, and investigate their spatial distribution within the intracluster field. We then focus on the GC candidates around dwarf galaxies and investigate their numbers, stacked luminosity distribution and stacked radial distribution. While the overall GC properties are consistent with those in the literature, an interesting over-representation of relatively bright candidates is found within a small number of relatively GC-rich dwarf galaxies. Our work confirms the capabilities of Euclid data in detecting GCs and separating them from foreground and background contaminants at a distance of 20 Mpc, particularly for low-GC count systems such as dwarf galaxies
Disease characteristics and monitoring of IDH1/IDH2-mutated acute myeloid leukemia
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L'homophilie des profils de bien-être au travail dans le contexte d'équipes de travail
No full textInternational audienceSi les amis de nos amis, ou même les amis d’amis de nos amis sont heureux alors nous sommes plus susceptibles de le devenir [6]. Mais qu’en est-il au travail ? Est-ce que les collaborateurs aux mêmes profils debien-être au travail (BET) ont davantage tendance à lier des relations ? Pour répondre à ce questionnement,le rapprochement des littératures sur le BET et sur l’analyse des réseaux (ARS) nous amène à observer si lesréseaux de collaboration et d’affinité interpersonnelle sont déterminés par l’homophilie de profils de BET.L’étude menée auprès d’un laboratoire de recherche d’une université de taille moyenne montre qu’il existeune structure de réseaux particulière entre les différents profils de BET mais que l’homophilie ne semble pasen être la cause. Ces structures de réseaux pourraient être la résultante d’autres tendances sociales, de lamultiplexité des réseaux ou de processus relationnels. Enfin, il n’est pas à exclure que ce soient les structuresde réseaux qui déterminent le profil de BET par un effet de contagion sociale [4]
A Comparative Study of Genetic Algorithm and Particle Swarm Optimization for Hybrid Renewable Systems with Battery and Hydrogen System
No full textInternational audienceThis paper presents a comparative study of Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) for optimal sizing of two hybrid renewable energy systems: Solar with Battery and Grid, and Solar with H2 System and Grid. Real-time energy consumption data from a university is used to model these systems, aiming to minimize costs while meeting energy demands and ensuring reliability. The performance of GA and PSO is compared based on solution quality, convergence speed, and computational efficiency. Results show that GA provides robust configurations, while PSO offers faster convergence. These findings support efficient and practical hybrid system design