Concordance dans le dépistage des enfants à risque pour les difficultés d’adaptation en milieu préscolaire

Cette étude examine l'apport de l'observation participante au dépistage précoce des enfants à risque en milieu préscolaire. Cent onze enfants de trois à quatre ans sont évalués par les éducateurs de leur groupe de garderie, à partir de 17 descripteurs de l'adaptation psychosociale en garderie. Les mesures font ressortir cinq profils comportementaux différenciés. Deux correspondent à des enfants perçus comme turbulents et retirés, rejoignant les distinctions traditionnelles entre troubles extériorisés et intériorisés. L'analyse de la fiabilité interobservateur indique que les éducateurs sont plus en accord pour les enfants évalués positivement que pour ceux qu'ils perçoivent moins adaptés. Ces résultats soulignent l'intérêt de l'observation participante pour détecter les trajectoires à risque. Ils montrent cependant la nécessité d'utiliser d'autres sources d'informations convergentes dans le dépistage précoce.This study examines the advantage which participant observation provides for the early diagnosis of at-risk pre-school children. Pre-school educators used a series of 17 descriptors of psycho-social adjustment to evaluate 111 children aged 3 to 4 years. These measures were used to describe five differentiated behavioral profiles. Two profiles describe children who are perceived as turbulent and retiring, these being traditional distinctions between exteriorizing, and interiorizing problems. Analysis of inter-observer reliability indicated that educators have higher agreement among each other in regard to those children who were positively evaluated than for those perceived as less adjusted. The results confirm the relevance of participant observation for detecting at-risk behavior. The authors point out, however, the need to use other information sources in early diagnosis.Este estudio examina el aporte de la obsevacion participante en la identificaciôn precoz de ninos "a riesgo" en medio prescolar. Ciento once ninos de très a cuatro anos han sido evaluados por los educadores de sus propios grupos de guarderia utilizando 17 descriptores de adaptacion psicosocial al medio prescolar. El trabajo pone en relieve cinco perfiles comportamentales diferenciados. Dos corresponden a ninos percibidos como revoltosos y alejados, coincidiendo con las distinciones tradicionales entre problemas exteriorizados e interiorizados. El anâlisis de fiabilidad interobservador indica que los docentes concuerdan mas en los casos de parvulos evaluados positivamente que en aquellos casos percibidos como menos adaptados. Estos resultados subrayan el interés suscitado por la observacion participante para detectar trayectorias "a riesgo". Sin embargo, los resultados muestran la necesidad de utilizar otras fuentes de informacion convergentes para la identificacion precoz de ninos "a riesgo".Diese Studie untersucht den Beitrag der teilnehmenden Beobachtung zum frûhzeitigen Erkennen von Problemfâllen im Vorschulbereich. Insgesamt wurden 111 Kinder zwischen 3 und 4 Jahren von den Erziehern ihrer jeweiligen Kindergarten untersucht, und zwar an Hand von 17 Kriterien psychosozialer Anpassung im Kindergarten. Daraus ergeben sich flinf verschiedene Verhaltensprofile. Zwei davon beziehen sich auf Kinder, die als "turbulent" oder "zurûckgezogen" eingestuft wurden, was dem traditionellen Unterschied von nach innen oder auEen abgeleiteten Stôrungen entspricht. Die Analyse der Beob-achtungszuverlâssigkeit weist darauf hin, dass die Erzieher starker mit den positiv beurteilten Kindern iibereinstimmen als mit den anpassungsschwierigen. Dièse Ergebnisse unterstreichen die Be-deutung der teilnehmenden Beobachtung zum Erkennen von potentiellen Problementwicklungen. Es ergibt sich jedoch auch die Notwendigkeit zusâtzlicher Informationsquellen, die sich fur die Friiherkennung als konvergent erweisen kônnten

Gérer l’autonomie dans la différence

Après avoir montré la complexité organisationnelle du système éducatif belge, l’auteur centre son propos sur les structures participatives mises en place dans les établissements de la communauté française. Il en donne un exemple et explique comment un chef d’établissement peut inciter ou faciliter les innovations

Crystal plasticity and phenomenological approaches for the simulation of deformation behavior in thin copper alloy sheets

In the expanding context of device miniaturization, forming processes of ultra thin sheet metals are gaining importance. Numerical simulation of these processes requires accurate material modeling. In this study, both the phenomenological modeling approach and the crystal plasticity finite element method (CPFEM) are considered. Theoretical definitions of both models, numerical implementation as well as their parameter identification procedures are outlined. Subsequently they are compared on a one to one basis, mainly with regards to their ability to predict mechanical responses for a variety of strain loading paths.Agence Nationale de la Recherche, ANR-12-RMNP-0009-0

Optimization of the experimental set-up for a turbulent separated shear flow control by plasma actuator using genetic algorithms

Since 1947, when Schubauer and Skramstad established the basis of the technology with its revolutionary work about steady state tools and mechanisms for the flow management, the progress of the flow control technology and the development of devices have progressed constantly. Anyway, the applicability of such devices is limited, and only few of them have arrived to the assembly workshop. The problem is that the range of actuation is still limited. Despite their operability limitations, flow control devices are of great interest for the aeronautical industry. The number of projects investigating this technology demonstrates the relevance of in the Fluid Dynamic field. The scientific interest focus not only on the industrial applications and the improvement of the technology, but also on the deep understanding of the physical phenomena associated to the flow separation, turbulence formation associated to the final drag reduction aim. A clear example of what has been mentioned is the EC MARS research project (MARS project, FP7 project number 266326). Its objectives are aimed to a better understanding of the Reynolds Stress and turbulent flow related to both drag reduction and flow control. The research was carried out through the analysis of several flow control devices and the optimization of the parameters for some of them was an important element of the research. When solving a traditional fluid dynamics optimisation problem numerical flowanalysis are used instead of experimental ones due to their lower cost and shorter needed time for evaluation of candidate solutions. Nevertheless, in the particular case of the selected flow control plasma devices the experimental measurement of the performance of each candidate configuration has been much quicker than a numerical analysis. For this reason, the corresponding optimisation problem has been solved by coupling an evolutionary optimization algorithm with an experimental device. This paper discusses the design quality and efficiency gained by this innovative coupling.Peer ReviewedPostprint (author's final draft

Inventaire de la faune apiforme (Hymenoptera, Apoidea) des quartiers Myosotis et Engeland à Uccle (Bruxelles, Belgique)

peer reviewedCe travail présente l’inventaire des abeilles sauvages (Hymenoptera Apoidea) observées dans l’ancien quartier Myosotis et le nouveau quartier Engeland de la commune d’Uccle à Bruxelles. Via une campagne d’échantillonnage dans les deux quartiers, 708 spécimens ont été capturés ou observés appartenant à 58 espèces différentes des 6 familles d’abeilles sauvages de Belgique. La faune apiforme capturée représente 14% de la faune belge et 28% de la faune bruxelloise. On y retrouve 10 espèces mono ou oligolectiques et 5 espèces font l’objet d’enjeux de conservation spécifiques selon la liste rouge des abeilles de Belgique. Quelques recommandations de gestion de conservation sont discutées dans ce travail en vue de favoriser au maximum la richesse de ces anthophiles pour la commune d’Uccle

Multiframe Scene Flow with Piecewise Rigid Motion

We introduce a novel multiframe scene flow approach that jointly optimizes the consistency of the patch appearances and their local rigid motions from RGB-D image sequences. In contrast to the competing methods, we take advantage of an oversegmentation of the reference frame and robust optimization techniques. We formulate scene flow recovery as a global non-linear least squares problem which is iteratively solved by a damped Gauss-Newton approach. As a result, we obtain a qualitatively new level of accuracy in RGB-D based scene flow estimation which can potentially run in real-time. Our method can handle challenging cases with rigid, piecewise rigid, articulated and moderate non-rigid motion, and does not rely on prior knowledge about the types of motions and deformations. Extensive experiments on synthetic and real data show that our method outperforms state-of-the-art.Comment: International Conference on 3D Vision (3DV), Qingdao, China, October 201

Multi-input genetic algorithm for experimental optimization of the reattachment downstream of a backward-facing step with surface plasma actuator

The practical interest of flow control approaches is no more debated as flow control provides an effective mean for considerably increasing the performances of ground or air transport systems, among many others applications. Here a fundamental configuration is investigated by using non-thermal surface plasma discharge. A dielectric barrier discharge is installed at the step corner of a backward-facing step (Reh=30000, Re¿=1650). Wall pressure sensors are used to estimate the reattaching location downstream of the step. The primary objective of this paper is the coupling of a numerical optimizer with an experiment. More specifically, optimization by genetic algorithm is implemented experimentally in order to minimize the reattachment point downstream of the step model. Validation through inverse problem is firstly demonstrated. When coupled with the plasma actuator and the wall pressure sensors, the genetic algorithm finds the optimum forcing conditions with a good convergence rate, the best control design variables being in agreement with the literature that uses other types of control devices than plasma. Indeed, the minimum reattaching position is achieved by forcing the flow at the shear layer mode where a large spreading rate is obtained by increasing the periodicity of the vortex street and by enhancing the vortex pairing phenomena. At the best forcing conditions, the mean flow reattachment is reduced by 20%. This article, with its experiment-based approach, demonstrates the robustness of a single-objective multi-design optimization method, and its feasibility for wind tunnel experiments.Postprint (published version

Experimental optimization by genetic algorithm for flow separation control with surface plasma actuator

Postprint (published version