Search results for " Methods"
showing 10 items of 4102 documents
Le score de propension : un guide méthodologique pour les recherches expérimentales et quasi expérimentales en éducation
2016
La méthode du score de propension devient de plus en plus populaire pour estimer les effets causaux d’un programme d’intervention. Si les applications empiriques de cette méthode sont encore rares dans les recherches en éducation, des exemples de son utilisation se trouvent aisément dans d’autres disciplines. Cependant, sa mise en place soulève plusieurs questions. L’objectif de cet article est de fournir des éléments de réponses guidant le chercheur et l’évaluateur du domaine de l’éducation pour l’estimation et l’utilisation du score de propension. Les différentes étapes de son application sont présentées pas à pas : évaluation du biais de sélection, construction du score de propension et …
An Artificial Decision Maker for Comparing Reference Point Based Interactive Evolutionary Multiobjective Optimization Methods
2021
Comparing interactive evolutionary multiobjective optimization methods is controversial. The main difficulties come from features inherent to interactive solution processes involving real decision makers. The human can be replaced by an artificial decision maker (ADM) to evaluate methods quantitatively. We propose a new ADM to compare reference point based interactive evolutionary methods, where reference points are generated in different ways for the different phases of the solution process. In the learning phase, the ADM explores different parts of the objective space to gain insight about the problem and to identify a region of interest, which is studied more closely in the decision phas…
Neutral Iron Emission Lines From The Day-side Of KELT-9b -- The GAPS Programme With HARPS-N At TNG XX
2020
We present the first detection of atomic emission lines from the atmosphere of an exoplanet. We detect neutral iron lines from the day-side of KELT-9b (Teq $\sim$ 4, 000 K). We combined thousands of spectrally resolved lines observed during one night with the HARPS-N spectrograph (R $\sim$ 115, 000), mounted at the Telescopio Nazionale Galileo. We introduce a novel statistical approach to extract the planetary parameters from the binary mask cross-correlation analysis. We also adapt the concept of contribution function to the context of high spectral resolution observations, to identify the location in the planetary atmosphere where the detected emission originates. The average planetary li…
The Gaia-ESO Survey: Structural and dynamical properties of the young cluster Chamaeleon i
2017
Investigating the physical mechanisms driving the dynamical evolution of young star clusters is fundamental to our understanding of the star formation process and the properties of the Galactic field stars. The young (~2 Myr) and partially embedded cluster Chamaeleon I is one of the closest laboratories for the study of the early stages of star cluster dynamics in a low-density environment. The aim of this work is to study the structural and kinematical properties of this cluster combining parameters from the high-resolution spectroscopic observations of the Gaia-ESO Survey with data from the literature. Our main result is the evidence of a large discrepancy between the velocity dispersion …
Search for cosmic sources in neutrino telescopes and time calibration in the ANTARES neutrino telescope
2018
Aunque la astronomía de neutrinos es una disciplina muy reciente, está resultando ser muy en un estado estimulante. Los diversos resultados publicados por la colaboración IceCube han mostrado la existencia de un flujo de neutrinos cósmicos de altas energías, del cual se desconoce su origen, y del que no se ha observado una dirección privilegiada. El telescopio de neutrinos ANTARES ha sido capaz de excluir la posibilidad de que algunos de los eventos observados por IceCube se hayan producido por una fuente puntual en la región del centro galáctico. Además, el último análisis de flujos difusos de ANTARES muestra un resultado compatible con el flujo observado por IceCube. Actualmente, existen …
Restoring Harmony in the Lifeworld? : Identity, Learning, and Leaving Preelite Sport
2020
Sport provides many youth participants with a central life project, and yet very few eventually fulfill their athletic dreams, which may lead them to disengage from sport entirely. Many studies have explored the processes of athletic retirement, but little is known about how youth athletes actually reconstruct their relationship with sport and embodiment postretirement. The authors explored these issues in the story of “Pilvi,” a Finnish alpine skier who disengaged from sport in her late adolescence. Employing an existential-phenomenological approach, they conducted six low-structured interviews with Pilvi, combined with visual methods, and identified key themes relating to the body, space,…
A study of the atmospherically important reactions between dimethyl selenide (DMSe) and molecular halogens (X2 = Cl2, Br2, and I2) with ab initio cal…
2012
The atmospherically relevant reactions between dimethyl selenide (DMSe) and the molecular halogens (X(2) = Cl(2), Br(2), and I(2)) have been studied with ab initio calculations at the MP2/aug-cc-pVDZ level of theory. Geometry optimization calculations showed that the reactions proceed from the reagents to the products (CH(3)SeCH(2)X + HX) via three minima, a van der Waals adduct (DMSe:X(2)), a covalently bound intermediate (DMSeX(2)), and a product-like complex (CH(3)SeCH(2)X:HX). The computed potential energy surfaces are used to predict what molecular species are likely to be observed in spectroscopic experiments such as gas-phase photoelectron spectroscopy and infrared matrix isolation s…
Kaon-proton strong interaction at low relative momentum via femtoscopy in Pb-Pb collisions at the LHC
2021
Physics letters / B 822, 136708 (2021). doi:10.1016/j.physletb.2021.136708
Conceptual design and simulation of a water Cherenkov muon veto for the XENON1T experiment
2014
XENON is a direct detection dark matter project, consisting of a time projection chamber (TPC) that uses xenon in double phase as a sensitive detection medium. XENON100, located at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, is one of the most sensitive experiments of its field. During the operation of XENON100, the design and construction of the next generation detector (of ton-scale mass) of the XENON project, XENON1T, is taking place. XENON1T is being installed at LNGS as well. It has the goal to reduce the background by two orders of magnitude compared to XENON100, aiming at a sensitivity of $2 \cdot 10^{-47} \mathrm{cm}^{\mathrm{2}}$ for a WIMP mass of 50 GeV/c$^{2}$. With…
Coupled fixed point results in cone metric spaces for -compatible mappings
2011
Abstract In this paper, we introduce the concepts of -compatible mappings, b-coupled coincidence point and b-common coupled fixed point for mappings F, G : X × X → X, where (X, d) is a cone metric space. We establish b-coupled coincidence and b-common coupled fixed point theorems in such spaces. The presented theorems generalize and extend several well-known comparable results in the literature, in particular the recent results of Abbas et al. [Appl. Math. Comput. 217, 195-202 (2010)]. Some examples are given to illustrate our obtained results. An application to the study of existence of solutions for a system of non-linear integral equations is also considered. 2010 Mathematics …