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Euler-type approximation for the invariant measure: An abstract framework
No full textWe establish a general framework to study the rate of convergence of a Euler type approximation scheme with decreasing time steps to the invariant measure, for a general class of stochastic systems. The error is measured in general Wasserstein distances, which enables to encompass cases with non global contractivity conditions. Our main assumption is a coupling property which is expressed in terms of the one-step approximation. We show that the proposed set-up can be applied to a wide range of equations that may be law dependent, such as Langevin equations, reflected equations, Boltzmann type equations and for a recent McKean Vlasov type model for neuronal activity
Organizing collective political action in a world in polycrisis: insights from Hannah Arendt and John Dewey
No full textInternational audienc
Exploiting Low Scanwidth to Resolve Soft Polytomies
No full textInternational audiencePhylogenetic networks allow modeling reticulate evolution, capturing events such as hybridization and horizontal gene transfer. A fundamental computational problem in this context is the Tree Containment problem, which asks whether a given phylogenetic network is compatible with a given phylogenetic tree. However, the classical statement of the problem is not robust to poorly supported branches in biological data, possibly leading to false negatives. In an effort to address this, a relaxed version that accounts for uncertainty, called Soft Tree Containment, has been introduced by Bentert, Malík, and Weller [SWAT’18]. We present an algorithm that solves Soft Tree Containment in 2^O(∆(T) k log(k)) · n^O(1) time, where k := sw(Γ ) + ∆(N) , with ∆(T) and ∆(N) denoting the maximum out-degrees in the tree and the network, respectively, and sw(Γ ) denoting the “scanwidth” [Berry, Scornavacca, and Weller, SOFSEM’20] of a given tree extension of the network, while n is the input size. Our approach leverages the fact that phylogenetic networks encountered in practice often exhibit low scanwidth, making the problem more tractable
Lexique de la photogrammétrie
No full textInternational audienceFrench-English glossary of photogrammetry vocabulary.Each entry in this glossary contains:-French term(s),-English term(s)-A definition in FrenchCe lexique a été conçu dans une démarche d’harmonisation, de standardisation et de normalisation du vocabulaire utilisé dans le domaine de la géomatique. Il est fondé sur le constat des usages dans le monde francophone. Les définitions ont été rédigées de manière à être aussi intuitives que possible, mais aussi rigoureuse que nécessaire.Aucun mot n’a été créé ou inventé par les rédacteurs de ce lexique. Un mot qui figure dans ce lexique a assurément été utilisé dans des contextes différents : il a été employé dans au moins deux sources bibliographiques différentes écrites par deux scientifiques différents, ou de deux cours différents donnés dans deux universités différentes, ou dans deux logiciels métiers différents créés par des entreprises différentes, etc.Quand un mot possède une traduction anglaise admise, celle-ci est donnée avec le mot en français. Quand un mot anglais n’a (à la connaissance des auteurs de ce lexique) pas d’équivalent français dans les usages, nous préconisons d’utiliser le mot anglais tel quel en le mettant en italique dans le texte écrit en français, ou de le prononcer en anglais dans un discours en français.Ce lexique reste en évolution permanente. Si vous connaissez un mot et que vous voulez le faire entrer dans ce lexique, ou que vous n’êtes pas d’accord avec l’usage ou la définition d’un mot, vous pouvez nous contacter pour étudier ensemble ces cas.Ce présent lexique est le chapitre 14 du lexique de l’Association Francophone de Topographie. Ainsi, la numérotation de chaque section commence par 14. Les définitions sont classées dans un ordre thématique, et un glossaire en fin de document classe les termes dans un ordre alphabétique
Pauvreté transitoire des consommateurs et reconfiguration de leurs pratiques de consommation
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Les 10 ans du projet pédagogique et de recherche en ludopédagogie EdUTeam
No full textLa vidéo proposée rentre dans le cadre d’un cycle de conférences dédié aux 10 ans du projet pédagogique est de recherche en ludopédagogie EdUTeam. Après une présentation générale par le responsable de l’équipe, un enseignant et deux étudiantes témoignent de leurs activités au sein du projet.EdUTeam est un projet de l'Institut de Recherche en Gestion (IRG, UR 2354) et de l'IAE Paris-Est classé en 2021 parmi les 10 plus importantes innovations pédagogiques mondiales mises en œuvre en Business School. L'objectif principal est d'étudier le serious gaming, c'est-à-dire le détournement des jeux de loisirs à des fins de formation. Les expérimentations et études sont menées au sein du game lab GamiXlab qui intègre une ludothèque de plus de 820 jeux de tous types début 2025. Le site Internet du projet (https://eduteam.fr/) recense l'ensemble des actualités et des productions de l'équipe projet EdUTeam
Quelques résultats sur les anneaux de Lie qui n'ont pas de chaîne infinie de centralisateurs
No full textIn the line of known results on groups, we show the existence of the nilpotent radical in Lie rings with minimal condition on centralizers. We also prove a form of Engel's theorem if the characteristic is zero.Dans la lignée des résultats existants pour les groupes, on montre que le radical nilpotent existe dans les anneaux de Lie qui n'ont pas de chaîne infinie de centralisateurs. On établit également un analogue du théorème d'Engel si la caractéristique est nulle
Hybridization of machine learning/GPR Full-Waveform Inversion for pavement tack coat characterization: Numerical validation
No full textInternational audienceThe characterization of tack coat layers in pavements using conventional techniques, such as forward processing applied to ground-penetrating radar (GPR), is challenging due to the low temporal resolution of raw signals, among other factors. In this research, we propose a double inverse method based on machine learning algorithms (SVM/SVR) combined with Full-Waveform Inversion (FWI), enabling robust detection and characterization of such thin layers. Machine learning (ML) methods applied to GPR signals have initially demonstrated the potential to detect structural anomalies from time signals (A-scans) through inverse global/local approaches. However, despite their performance, these decision-making algorithms have proven insufficiently robust when faced with various physical phenomena, whose effects are not highlighted in the raw GPR signals used in the training database. Consequently, we propose adding a priori material characteristics using FWI in order to boost the machine learning model. This hybridization between ML and FWI data inversion has been successfully validated on very wide numerical databases issued from an FDTD forward model. This double inverse method has shown an improved decision-making process by integrating a priori physical information
RFID sensor development for corrosion monitoring in bridges cables
No full textInternational audienceThis article investigates the RFID technology for corrosion monitoring of prestressed concrete structures. Common corrosion detection methods are time-consuming and expensive, leading to challenges in early detection, especially in inaccessible areas. RFID technology offers advantages such as wireless operation, small size, and easy integration. The present paper aims at applying RFID corrosion sensors to the monitoring of steel strands used in prestressed bridges. As it will be shown, corrosion of both steel strands and sensitive parts of sensors is governed by localized corrosion. When the depth of pits become higher than 150 m on the steel strands, an alert is triggered by sensors. With this alert, maintenance actions can be planned. The paper also validates the radio-frequency communication with sensors embedded within a High-Density Polyethylene (HDPE) sheath through in-situ testing. It is proved that embedded sensors in HDPE sheath can be manually interrogated by operators during inspections with a reading distance of 25 cm or more, depending on the location of the sensors with respect to strands. These findings highlight the interest of the method and contributes to the advancement of corrosion monitoring strategies for prestressed bridges, enabling improved maintenance practices and extended durability.</div
Three-Compartment Phenotype Concept of Total Knee Arthroplasty Alignment: Mismatch Between Distal Femoral, Posterior Femoral, and Tibial Joint Lines
No full textInternational audienceBackgroundThe purpose of the study was to assess whether patients who have different coronal alignment variations (functional knee phenotypes (FKP)) have distinctly different rotational alignment variations to justify an extension of the FKP concept to include rotational alignment parameters. The goals of the study were to: 1) determine the frequency of bony congruence between the anterior, distal, and posterior femoral and proximal tibial joint lines using the extended FKP concept; and 2) connect these findings to clinical practice by simulating the impact of different alignment concepts on the most common FKP.MethodsThe posterior condylar angle (PCA) and anterior trochlear angle (ATA) were measured in 265 knees without osteoarthritis (OA). The PCA measurements of 2,692 OA knees with OA were extracted from the database. The patients were categorized into phenotypes based on these parameters. A phenotype represents an alignment variation of either the posterior (= PCA) or anterior femoral joint line (= ATA) in the axial plane. Rotational phenotypes (i.e., combination of alignment variations of the anterior and posterior femoral joint lines) were linked with the coronal phenotypes of these patients. The effect of three alignment concepts (mechanical, restricted, and unrestricted kinematic) on the most common FKPs was assessed.ResultsThe distribution of the five most common coronal phenotypes did not differ among rotational phenotypes. The ATA and PCA were aligned parallel in 14.3% of the non-OA population. Distal femoral joint line (FMA), proximal tibial joint line (TMA), and PCA were aligned in parallel in 17.0 and 11.2% of the non-OA and OA populations, respectively. All four joint lines (FMA, TMA, PCA, and ATA) were aligned in 2.3% of the non-OA population.ConclusionIt is crucial to emphasize that preoperative assessment of a patient's anatomy should include the anterior and posterior femoral joint lines. The extended FKP concept could aid in this assessment and help identify patients at risk of complications due to malalignment or those likely to benefit from a particular alignment concept