STB-VMM: Swin Transformer Based Video Motion Magnification

The goal of video motion magnification techniques is to magnify small motions in a video to reveal previously invisible or unseen movement. Its uses extend from bio-medical applications and deepfake detection to structural modal analysis and predictive maintenance. However, discerning small motion from noise is a complex task, especially when attempting to magnify very subtle, often sub-pixel movement. As a result, motion magnification techniques generally suffer from noisy and blurry outputs. This work presents a new state-of-the-art model based on the Swin Transformer, which offers better tolerance to noisy inputs as well as higher-quality outputs that exhibit less noise, blurriness, and artifacts than prior-art. Improvements in output image quality will enable more precise measurements for any application reliant on magnified video sequences, and may enable further development of video motion magnification techniques in new technical fields.Comment: Code available at: https://github.com/RLado/STB-VM

Effects of photon reabsorption phenomena in confocal micro-photoluminescence measurements in crystalline silicon

Confocal micro-photoluminescence (PL) spectroscopy has become a powerful characterization technique for studying novel photovoltaic (PV) materials and structures at the micrometer level. In this work, we present a comprehensive study about the effects and implications of photon reabsorption phenomena on confocal micro-PL measurements in crystalline silicon (c-Si), the workhorse material of the PV industry. First, supported by theoretical calculations, we show that the level of reabsorption is intrinsically linked to the selected experimental parameters, i.e., focusing lens, pinhole aperture, and excitation wavelength, as they define the spatial extension of the confocal detection volume, and therefore, the effective photon traveling distance before collection. Second, we also show that certain sample properties such as the reflectance and/or the surface recombination velocity can also have a relevant impact on reabsorption. Due to the direct relationship between the reabsorption level and the spectral line shape of the resulting PL emission signal, reabsorption phenomena play a paramount role in certain types of micro-PL measurements. This is demonstrated by means of two practical and current examples studied using confocal PL, namely, the estimation of doping densities in c-Si and the study of back-surface and/or back-contacted Si devices such as interdigitated back contact solar cells, where reabsorption processes should be taken into account for the proper interpretation and quantification of the obtained PL data.Peer ReviewedPostprint (published version

La ruta del mosaico romano: el sur de hispania (Anadalucía y Algarve)

A Hispânia meridional corresponde ao sul de duas províncias romanas – a Bética (actual Andaluzia) e a Lusitania (Portugal) – que tiveram grande prosperidade económica, desde a época de Augusto até ao final da Antiguidade (finais do século IV). Os mosaicos que decoravam o chão das casas mais ricas aparecidas nos últimos vinte anos nas escavações em cidades – como em Faro/Ossonoba, na Lusitania e em Écija/ Astigi, na Bética – e nas villae rurais que se encontram maioritariamente nos arredores das cidades – como em Cerro da Vila (Vilamoura)e em Milreu (Estoi), no Algarve – demonstram o elevado nível de desenvolvimento económico,social e cultural das duas províncias durante o período compreendido entre os séculos I e IV d.C

Magnetostratigraphy and stable isotopes record of Paleogene global climate events in a 30Myr expanded foreland basin succession, Isabena river, Southern Pyrenees, Spain

Past sedimentary archives provide invaluable comparative insights to understand Earth¿s surface reaction to climate shifts and perturbations. Foreland basins are particularly interesting settings for investigating the sedimentary record of ancient climate perturbations because their high-accommodation and high-sedimentation rates favour protracted and expanded records that complement more distal oceanic records. In addition, due to their proximity to source areas, they provide direct information on the land surface response to the regional impacts of global climate shifts. However, besides climate signals, the stratigraphic record of foreland basins is subject to a broad range of other factors that make its interpretation challenging. Indeed, foreland basins are naturally sensitive to the influence of tectonics on sediment production and accommodation, either associated with the long-term tectonic evolution of the orogen-basin system, or with the more local and regional shorter-term structural dynamics and geodynamic perturbations. Moreover, if connected to oceanic domains, eustatic sea-level oscillations can also combine with the above factors in determining final stratigraphic patterns. Over the last two decades, a large body of paleoclimate work has produced new and crucial data on global climate events that have affected our planet. In particular, a suite of global climate perturbations (warming, cooling) have been identified in the Paleogene, thanks to stable isotope of C and O, with some major global warming events such as the PETM, ETM2&3, the EECO, the MECO and others that have fundamental implications for the current global climate crisis. This well-established climatic template provides a unique opportunity to test the impact of climate on surface systems in deep time, particularly during the Paleogene hothouse. Therefore, we here present our work on the Isabena section in the South Pyrenean Foreland basin, which is a uniquely continuous and well exposed succession encompassing from the upper Cretaceous to the upper Eocene. We sampled continuously at 1-10 meters intervals over the 4 km-thick succession, from the lower Eocene to the upper Eocene. This sampling results in a new and continuous magnetostratigraphy covering almost 30 Myr of stratigraphic evolution, and a new high-resolution stable isotope record of carbon and oxygen over the Paleogene. These results combined with sedimentological descriptions and stratigraphic analyses reveal the links between important sedimentation changes and global climate events. Preliminary results suggest that hyperthermal events are often associated with enhanced sediment transport and clastic deposition in the basin, while intervals comparatively cooler seem to be more prone to enhanced carbonate accumulation

Introduction à la microscopie confocale et techniques de spectroscopie associées pour la caractérisation de matériaux pour l’électronique et le PV

National audienc

Degradation of surface passivation at the surroundings of laser processed regions in c-Si solar cells studied by micro-photoluminescence

National audienc