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Detection of jovian kilometric and hectometric auroral radio harmonics with juno/waves in situ measurements.
No full textInternational audienceAuroral radio emissions from Earth, Saturn, and Jupiter are now known to all be generated by the cyclotron maser instability near the electron cyclotron fundamental frequency f_ce. This common generation mechanism results in similar wave properties in terms of beaming and polarization. However, while harmonics at 2 × f_ce and 3 × f_ce have been identified in the terrestrial and kronian cases, none of the components of Jupiter’s auroral radio spectrum had been associated with harmonics. In this study, we confirm the existence of first harmonic emissions for the Jovian broadband-kilometric (bKOM) and hectometric (HOM) components (200-700 kHz) in 6 cases using in situ data from Juno/Waves observations close to the source. Among these cases, 2 second harmonics were also identified. These harmonics are three orders of magnitude weaker than the associated fundamental and were identified in regions where the f_pe/f_ce(f_pe the electron plasma frequency) ratio is of the order of 10^-2. This discovery confirms the universality of the CMI and suggests that harmonics in the decametric range could exist
Optimizing Shift Angle Topologies for PCB Toroidal Inductors Using Solenoid Models under DC Boundaries
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Factor of safety analysis in fractured multi-layered slopes
No full textInternational audienceSeveral causative factors influence slope stability and the resulting factor of safety, including lithology, discontinuities, variation of water table level, and weak mechanical levels. We have investigated how rock discontinuities, which facilitate the initiation and influence the geometry of landslides, control the slope stability of multi-layered slopes combining a strong cap rock overlying weak and strong layers. The Shear Strength Reduction method was used to estimate the impact of fractures and other causative factors on the stability of multi-layered slopes with different water table levels as potential triggering mechanisms. The study highlighted that although major vertical discontinuities can localize failures reducing the potential mobilized rock volume, they have little influence on the safety factor. Weak mechanical levels have shown the most significant importance in localizing the failure surface in depth. In contrast, the water table level strongly influences the factor of safety and the resulting geometry and failure mechanism: high water levels favor toppling, while low water levels favor circular failure surfaces
Virtual field trips: an analysis of their characteristics, elements, and approaches
No full textInternational audienceThis empirical study investigated the approaches to and elements of virtual field trips (VFTs). Its aim was to work out VFT design elements and to identify similarities and differences in their structures and content; quality criteria for VFTs were then derived from this analysis. The sample comprised a total of 107 VFTs, most of which were developed at universities using various digital tools, such as ArcGIS Online, Google Maps, and Genially. The VFTs were available in different languages, with English and Spanish being particularly well represented. We used qualitative content analysis to analyze the content before inductively forming categories on which the analysis was based. The results showed considerable variability in VFT approaches, particularly in the spaces presented, the scientific quality of VFTs, and the possibilities of interaction. In the future, digital learning environments could be developed based on these findings. For example, educational institutions could use the findings to design high-quality and effective VFTs with the potential to enrich geographical education in the context of digital learning environments
Intégrer les excursions virtuelles et sur le terrain dans l'enseignement géographique : perspectives des universités françaises et espagnoles
No full textInternational audienceIn our increasingly interconnected world, understanding sustainability issues and global change is crucial. Educators must preparefuture generations to address complex challenges such as climate change, biodiversity loss, and social disparities. Specialized training isessential for students and educators alike. Higher education programs are leveraging information technologies to enhance teaching methods,while geotechnologies aid in identifying environmental changes. Fieldwork remains valuable for integrating theoretical concepts withreal-world experiences. This paper explores the integration of virtual and place-based field trips in geoeducation, presenting theoreticalframeworks and methodologies for experimentation and evaluation. This article does not take an empirical approach. Instead, the aimis to theorise the relationship between the virtual and real fieldtrip using an exploratory approach. Two primary approaches have beendelineated: the sequential approach, which integrates field trips and virtual field trips, either prior to or following, asynchronously, and themixed approach, which entails conducting VFTs while in the field, concurrently, i.e. synchronously.Each approach emphasizes different learning objectives, with the sequential approach focusing on critical and spatial thinking, while themixed approach facilitates comprehensive fieldwork beyond observatio
Scalable Hydrodynamics on multiple Field-Programmable Gate Arrays (FPGAs)
No full textInternational audienceThis paper presents scalable 2D and 3D Hydrodynamics solver implementations on FPGAs using Intel’s oneAPI framework, addressing challenges in porting stencil-based computations from CPU/GPU architectures on FPGAs.FPGAs offer customizable hardware with on-chip memory that can be custom-tailored for High Performance Computing (HPC) applications. Despite a much lower throughput, FPGAs achieve comparable energy efficiency with domain decomposition compared to NVIDIA A100 GPU. Optimizations leverage FPGA’s large cache to minimize data streaming and ensure data reuse, reducing memory bandwidth.Domain decomposition enabled pipeline duplication for scalable single FPGA workload, but also the distribution of the work on two Agilex 7 cards.This work demonstrates FPGA viability for computationally intensive simulations, contributing to scalable algorithms for heterogeneous HPC systems and offering insights for exascale computing
Will you follow your job to the suburbs?
No full textInternational audienceWe examine how relocations from the center to the suburbs of establishments employing mainly skilled workers affect the composition and wages of their employees. Using data from the Paris metro area, we find that these relocations increase average commuting time by 19%. In response, firms compensate highly paid workers with 10 to 20% of their hourly wage per additional hour of commuting. Lower-paid workers receive no compensation and are more likely to leave. Consistent with workers valuing locational amenities, we find little increase in separation and no wage adjustment for increased commuting time when establishments relocate to more attractive neighborhoods
Microwave spectroscopy of ultracold-sodium least-bound molecular states
No full textInternational audienceWe have performed microwave spectroscopy of sodium least-bound molecular states, improving the precision of the knowledge of their energies at zero magnetic field by almost three orders of magnitude. Our experimental observations give us access also to states submitted to predissociation, a phenomenon where a bound molecular state can naturally decay into the continuum. Our findings are compared to numerical calculations based on the latest interpolation of sodium interaction potentials and show good agreement, with slight discrepancies in the zero-field energy of the molecular states, suggesting a need for small adjustment of the interaction potentials
Annie Ernaux et l’écriture. Projet, processus et projection
No full textInternational audienceThis article explores the metareflexive dimension of Annie Ernaux’s writing by examining the way the author interrogates the act of writing within her works themselves. The aim is not to show how the text generates a metapoetic reflection, but rather to identify, within the work in progress, the role and functioning of these reflexive returns. Drawing on a corpus of works published up to Le jeune homme (2022), the study shows how the text reflects upon itself at multiple levels: in its intention (the text as project), in its unfolding (the text as process), and in its realization (the text as projection). Focused on the metadiscourse that accompanies creation, the article demonstrates that Ernaux’s writing is both a form of inquiry and a construction in motion.L’article explore la dimension métaréflexive de l’écriture d’Annie Ernaux en examinant la façon dont l’autrice interroge l’acte d’écrire au sein même de ses oeuvres. L’analyse ne vise pas à montrer comment le texte suscite une pensée d’ordre métapoétique, mais à cerner, au sein de l’oeuvre en cours, le rôle et le fonctionnement de ces retours réflexifs. En s’appuyant sur un corpus constitué des oeuvres publiées jusqu’à Le jeune homme (2022), l’étude montre comment le texte se pense et se réfléchit de façon multiscalaire, tout d’abord dans sa visée (le texte comme projet), dans son déroulement (le texte comme processus) et dans son accomplissement (le texte comme projection). Centré sur le métadiscours qui accompagne la création, l’article montre que l’écriture d’Ernaux est à la fois une recherche et une construction en mouvement
Behaviour of eco-friendly mortar containing recycled concrete sand in fresh and hardened states
No full textInternational audienceThe use of recycled concrete aggregates (RCA) is one of the solutions to the problems of both the high demand for natural aggregates by the construction industry and the reduction of landfill demolition debris overload. However, the production of concrete or mortar based on RCA with qualities similar to those made with natural aggregates (NA) poses challenges. The main objective of this experimental study is to determine the influence of replacing 20%, 40%, and 60% of natural sand (NS) with recycled concrete sand (RCS) on the mechanical and physical properties of eco-friendly mortar. The results obtained revealed that RCS, rich in attached mortar, exhibits low physical properties such as low density, rough grain shape, and highwater absorption. Regarding the mechanical behaviour of the mortar produced, the results show that the presence of RCS has a positive impact on the compressive strength (Sc). However, it has a negative effect on shrinkage