Light-Fidelity (LiFi) is becoming increasingly popular in both academic and industrial circles. Therefore, several companies developing LiFi products, among which Oledcomm, have emerged over the past few years so that market feedback is now available. In this paper, the recurring feedback we identified, as LiFi vendor, are first detailed. The main use cases and existing products are then reviewed, with a specific focus on the LiFiMAX solution for secure indoor networking. Finally, ongoing standardization and ecosystem development initiatives are discussed, along with some of the major technical challenges that remain.

INSPIRE-SAT 7 is a French 2-Unit CubeSat (11.5 × 11.5 × 22.7 cm) primarily designed for Earth and Sun observation. INSPIRE-SAT 7 is one of the missions of the International Satellite Program in Research and Education (INSPIRE). Twice the size of a 4 × 4 Rubik’s Cube and weighing about 3 kg, INSPIRE-SAT 7 will be deployed in Low Earth Orbit (LEO) in 2023 to join its sister satellite, UVSQ-SAT. INSPIRE-SAT 7 represents one of the in-orbit demonstrators needed to test how two Earth observation CubeSats in orbit can be utilized to set up a satellite constellation. This new scientific and technological pathfinder CubeSat mission (INSPIRE-SAT 7) uses a multitude of miniaturized sensors on all sides of the CubeSat to measure the Earth’s energy budget components at the top-of-the-atmosphere for climate change studies. INSPIRE-SAT 7 contains also a High-Frequency (HF) payload that will receive HF signals from a ground-based HF transmitter to probe the ionosphere for space weather studies. Finally, this CubeSat is equipped with several technological demonstrators (total solar irradiance sensors, UV sensors to measure solar spectral irradiance, a new Light Fidelity (Li-Fi) wireless communication system, a new versatile telecommunication system suitable for CubeSat). After introducing the objectives of the INSPIRE-SAT 7 mission, we present the satellite definition and the mission concept of operations. We also briefly show the observations made by the UVSQ-SAT CubeSat, and assess how two CubeSats in orbit could improve the information content of their Earth’s energy budget measurements. We conclude by reporting on the potential of future missions enabled by CubeSat constellations.

Les corpus numériques pour la didactique des langues : de la formation des enseignants à l'élaboration de dispositifs d'apprentissageGallicagram : les archives de presse sous les rotatives de la statistique textuelleGallicagram: applying textual statistics to press archives

Gallicagram est un outil de lexicométrie développé pour la recherche en sciences humaines et sociales. Il offre aux chercheurs un moyen de tester rigoureusement leurs hypothèses et de quantifier les effets observés en tirant profit de très vastes bases de données linguistiques, délimitées, accessibles et structurées. La maîtrise des corpus, l'accès aux documents exploités, le traitement distinct de la presse et des livres ainsi que les outils d'analyse intégrés au logiciel lui permettent d'échapper aux critiques portées contre Google Ngram Viewer, dont il s'inspire. Cet article présente le logiciel et illustre ses applications possibles, en particulier dans le champ de l'histoire contemporaine.