Parametric Analysis of an Active Winglet Concept for High Aspect Ratio Wing Using CFD/CSM Computations

This paper presents a parametric analysis of an active winglet concept applied to a high aspect ratio wing. The technology studied here only consists in a single degree of freedom wing-tip whose only the cant angle deflection can be controlled. The main parameters under study are the hinge line location and its orientation with respect to the longitudinal axis of the aircraft. High-fidelity aerodynamic and structural computations are used to assess the impact of the device on both drag and loads. The influence of cant angle deflections on flutter characteristics is also evaluated. First a "wing only" configuration is studied and the results are compared with complete aircraft computations to take into account the contributions due to the trim. It is shown that the hinge line parameters highly influence the drag evolution with cant angle but with limited impact on the minimum area - in which we are interested in. Loads are significantly impacted by both cant variations and hinge line geometry. Regarding dynamic characteristics, the mode sequence is dependent on the cant deflection and massively impacts flutter onset

Classification d'habitat et détermination de cibles de conservation pourune approche de planification de la conservation en Manche orientale

National audiencePour être efficace, l'approche de planification de la conservation requiert que les objectifs de conservation, définis dans les textes réglementaires pour les habitats ou les espèces, soient traduits en cibles de conservation précises et explicites. En utilisant la méthode des relations aire-espèces, il est intéressant d'étudier dans quelle mesure le choix de la typologie d'habitat et des espèces utilisées influence les cibles. La méthode utilisée est développée dans cet article

Habitat modelling predictions highlight seasonal relevance of Marine Protected Areas for marine megafauna

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Spatial conservation prioritization for mobile top predators in French waters: comparing encounter rates and predicted densities as input

International audienceEU member states have to develop their Natura 2000 networks in their national waters to fulfill their conservation obligations regarding species and habitats listed in the Birds and Habitats directives. In France, a coastal network of Natura 2000 areas exists since 2008 but it had to be completed in offshore waters for some marine megafauna species. The SAMM aerial surveys (Aerial Census of Marine Megafauna) which occurred in winter 2011 and summer 2011–2012 over a large area comprising the whole metropolitan French Economic Exclusive Zone produced sighting data for species listed in the Birds and Habitats directives. These data produced different types of species distribution data: encounter rates and predicted densities by kriging and habitat modelling. Using these species distribution data, the aim of the present study was to compare these different types of inputs in the same conservation prioritization process to complete the existing Natura 2000 network in French waters. We ran prioritization analyses using the encounter rates only (scenario 1) then using the predicted densities provided by kriging and habitat modelling (scenario 2). We then compared the outputs of the two prioritization processes. The prioritization outputs were different but not in contradiction, with similar areas appearing as important to reach the conservation targets. Habitat models were thought to provide better pictures of seasonal species distributions and informed scientists about the phenology and ecology of species. However, the use of encounter rates as input data for the prioritization process in the Natura 2000 program is acceptable provided that sufficient survey effort is available

A partial metabolic pathway enables group b streptococcus to overcome quinone deficiency in a host bacterial community.

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