Annotation de partitions musicales dynamiques

Cet article traite de l'annotation visuelle à main levée de partitions musicales dynamiques : par dynamique, nous entendons la possibilité de recomposer, à la volée, les différents objets graphiques à l'intérieur de la page, ce qui nécessite de représenter les différentes annotations en conséquence. Nous décrivons ici les difficultés rencontrées et les solutions apportées au fil du développement de cet outil

Nanoscale heat transfer at contact between a hot tip and a substrate

Hot tips are used either for characterizing nanostructures by using scanning thermal microscopes or for local heating to assist data writing. The tip-sample thermal interaction involves conduction at solid-solid contact as well as conduction through the ambient gas and through the water meniscus. We analyze those three heat transfer modes with experimental data and modeling. We conclude that the three modes contribute in a similar manner to the thermal contact conductance but they have distinct contact radii ranging from 30 nm to 1 micron. We also show that any scanning thermal microscope has a 1-3 microns resolution when used in ambient air

Seabird Modulations of Isotopic Nitrogen on Islands

The transport of nutrients by migratory animals across ecosystem boundaries can significantly enrich recipient food webs, thereby shaping the ecosystems’ structure and function. To illustrate the potential role of islands in enabling the transfer of matter across ecosystem boundaries to be gauged, we investigated the influence of seabirds on nitrogen input on islands. Basing our study on four widely differing islands in terms of their biogeography and ecological characteristics, sampled at different spatial and temporal intervals, we analyzed the nitrogen isotopic values of the main terrestrial ecosystem compartments (vascular plants, arthropods, lizards and rodents) and their relationship to seabird values. For each island, the isotopic values of the ecosystem were driven by those of seabirds, which ultimately corresponded to changes in their marine prey. First, terrestrial compartments sampled within seabird colonies were the most enriched in δ15N compared with those collected at various distances outside colonies. Second, isotopic values of the whole terrestrial ecosystems changed over time, reflecting the values of seabirds and their prey, showing a fast turnover throughout the ecosystems. Our results demonstrate that seabird-derived nutrients not only spread across the terrestrial ecosystems and trophic webs, but also modulate their isotopic values locally and temporally on these islands. The wealth of experimental possibilities in insular ecosystems justifies greater use of these model systems to further our understanding of the modalities of trans-boundary nutrient transfers

TorusDesktop: Pointing via the Backdoor is Sometimes Shorter

International audienceWhen pointing to a target on a computer desktop, we may think we are taking the shortest possible path. But new shortcuts become possible if we allow the mouse cursor to jump from one edge of the screen to the opposite one, i.e., if we turn the desktop into a torus. We discuss the design of TorusDesktop, a pointing technique that allows to wrap the cursor around screen edges to open this pointing backdoor. A dead zone and an off-screen cursor feedback make the technique more usable and more compatible with everyday desktop usage. We report on three controlled experiments conducted to refine the design of the technique and evaluate its performance. The results suggest clear benefits of using the backdoor when target distance is more than 80% the screen size in our experimental conditions

Thermal nanometrology and scanning thermal microscopy

International audienc

Etude du transfert de chaleur par le ménisque d'eau formé au contact entre une pointe chaude micrométrique et une surface

International audienceNous étudions l'effet du ménisque d'eau sur le transfert de chaleur entre une pointe chaude et différents échantillons en utilisant la microscopie thermique à sonde locale (SThM). L'interaction thermique entre la pointe et l'échantillon dépend fortement de la température de la pointe. L'analyse de cette dépendance fait apparaître une température de transition entre deux régimes distincts de contribution du ménisque à cette interaction. Les variations des forces de détachement de la pointe en fonction de sa température moyenne montrent que le film d'eau disparait quasiment lorsqu'une température moyenne d'environ 125 °C est dépassée. Suite à ces résultats, une discussion est menée et quelques perspectives sont proposées