1,721,009 research outputs found
CERN (HL-LHC): the construction experience for the underground works at Point 5
No full textHigh-Luminosity LHC (HL-LHC) is the new project aiming to upgrade the underground particle accelerator Large Hadron Collider (LHC), at Point 1 (ATLAS in Switzerland) and Point 5 (CMS in France). This paper describes the construction experience for the new underground works at Point 5, located near the existing LHC tunnel. From a geological point of view, the site lies in an area covered by Quaternary moraine with the presence of two independent aquifers. The outcrop consists of Molasse, sub-horizontal lenses of heterogeneous sedimentary rock, known in this area to locally retain hydrocarbons and to have potential swelling behaviour. The main challenges of the project were related to the limitation of vibrations and settlements induced from the excavation activities, which might degrade the operation of the in-use LHC machines. This paper presents the local geology, the monitoring data recorded and the optimizations performed during the excavations together with the contractual management aspects. The completion of the works is scheduled for September 2022
Sociétés africaines de l'information
No full textCe numéro est publié en association avec NETSUDS - Les cahiers de sciences sociales sur les enjeux des technologies de la communication dans les Suds - Directeur de la publication : Annie Chéneau-Loquay. L'édition de ce numéro est liée au projet intitulé eAtlas Francophone de l'Afrique de l'Ouest, qui a reçu l'appui de l'Agence Universitaire de la Francophonie. Les textes rassemblés ici constituaient initialement le matériau des Actes des Rencontres africaines de l'eAtlas. Ce matériau a été remanié et augmenté pour publication dans ce qui se présente comme le premier numéro commun de la Revue NETCOM et des Cahiers NETSUDS. Les coordinateurs du projet tiennent à remercier les différents personnes qui se sont impliquées autour de ce numéro, tant pour la relecture critique (Clarisse Didelon, Marina Duféal, Loic Grasland, Céline Rozenblat, Charlotte Ullmann), que pour la finalisation des textes. Ils remercient en particulier Henry Bakis, Bernard Corminboeuf, Annie Cheneau-Loquay et Philippe Vidal sans le travail desquels ce numéro n'aurait pu être publié sous cette forme
Sociétés africaines de l'information
No full textCe numéro est publié en association avec NETSUDS - Les cahiers de sciences sociales sur les enjeux des technologies de la communication dans les Suds - Directeur de la publication : Annie Chéneau-Loquay. L'édition de ce numéro est liée au projet intitulé eAtlas Francophone de l'Afrique de l'Ouest, qui a reçu l'appui de l'Agence Universitaire de la Francophonie. Les textes rassemblés ici constituaient initialement le matériau des Actes des Rencontres africaines de l'eAtlas. Ce matériau a été remanié et augmenté pour publication dans ce qui se présente comme le premier numéro commun de la Revue NETCOM et des Cahiers NETSUDS. Les coordinateurs du projet tiennent à remercier les différents personnes qui se sont impliquées autour de ce numéro, tant pour la relecture critique (Clarisse Didelon, Marina Duféal, Loic Grasland, Céline Rozenblat, Charlotte Ullmann), que pour la finalisation des textes. Ils remercient en particulier Henry Bakis, Bernard Corminboeuf, Annie Cheneau-Loquay et Philippe Vidal sans le travail desquels ce numéro n'aurait pu être publié sous cette forme
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Prejudices: An Investigation Into Barriers of Humanity
No full textBy bringing people closer together, the phenomenon of globalisation not only accentuates differences but also it reinforces the sense of identity and belonging. This paradoxical and dynamic picture puts us straight before the challenge as to how to accommodate differences in order to live peacefully together. The gulf between “us” and “them” become more and more visible. The perception we can have of “others” remains deeply shaped by the values and precepts we learn in our respective cultural and educational circles. Yet, because men are not mere cultural products, individual responsibility and rational deliberation play an important role in the ways we approach “others.” In this article, we investigate prejudices as a phenomenon that is in the heart of above-mentioned issues. After a brief investigation into the nature of a prejudice, the paper outlines two main philosophical positions that either rehabilitate prejudices (Hans-Georg Gadamer) or calls for their abandonment (Descartes). The author argues that, despite the good arguments to be found in both positions, the nature of prejudices—as “something not yet knowledge”—puts upon us a kind of “moral and epistemological obligation” to overcome them, in order to do justice to ourselves and to our fellowmen, and construct sustainable and peaceful societies
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Inverse problems for parameter estimation of mathematical models : Application to population dynamics
No full textL’objectif de cette thèse est d’effectuer une étude d’identifiabilité de paramètres d’un modèle de polymérisation décrit par un système d’équations différentielles ordinaire (EDO). Dans un premier temps, nous effectuons une synthèse de la littérature relative aux problèmes inverses d’identifiabilité de paramètres. Cette étude est plus que nécessaire pour asseoir une bonne base théorique afin de pouvoir proposer d’autres approches ou des combinaisons d’approches permettant de résoudre des problèmes inverses. Dans un deuxième temps, nous effectuons l’analyse d’identifiabilité de paramètres à partir d’un modèle de polymérisation/dépolymérisation établi dans le cadre de la modélisation de la maladie d’Alzheimer. Nous commençons par bâtir un cadre formel d’étude d’identifiabilité s’appliquant aux systèmes d’EDO linéaires et non-linéaires. Ce cadre nécessite la connaissance d’un espace de vie de la solution du problème d’EDO. En conséquence, nous déterminons un cadre fonctionnel respectant les conditions biologiques imposées par le modèle, puis nous prouvons l’existence et l’unicité de la solution c’est-à-dire le caractère bien posé du modèle. Le modèle considéré est basé sur l’hypothèse du cascade amyloïde qui est assez dominante dans la connaissance actuelle sur la biologie concernant la maladie d’Alzheimer. Dans cette hypothèse du cascade amyloïde, la protéine Abeta (amyloïde sans forme de feuille bêta) est considérée comme responsable de la mort extracellulaire des neurones. Ces Abeta de par leur structure amyloïde peuvent agréger d’une part d’autres protéines par polymérisation et augmenter aussi leur taille et d’autre part spontanément pour former un noyau de protéines Abeta (nucléation) d’une taille donnée. Tout ce travail de thèse tourne autour de l’estimation du taux de nucléation qui est non accessible expérimentalement. Cette estimation est faite par des techniques liées à la résolution de problèmes inverses ou de problème de contrôle optimal. Nous discutons, interprétons et simulons numériquement les résultats obtenus.The aim of this thesis is to carry out an identifiability study of the parameters of a polymerization model described by a system of ordinary differential equations (ODE). First, we review the literature on inverse parameter identifiability problems. This survey is essential to establish a sound theoretical basis for proposing other approaches or combinations of approaches to solving inverse problems. In a second step, we carry out parameter identifiability analysis based on a polymerization/depolymerization model established in the context of Alzheimer’s disease modeling. We begin by building a formal framework for studying identifiability that applies to both linear and non-linear ODE systems. This framework requires knowledge of a life space of the solution of the ODE problem. Consequently, we determine a functional framework that respects the biological conditions imposed by the model, and then prove the existence and uniqueness of the solution, i.e. the well-posedness of the model. The model considered is based on the amyloid cascade hypothesis, which is fairly dominant in current knowledge of the biology of Alzheimer’s disease. In this amyloid cascade hypothesis, the protein A (amyloid without beta-sheet form) is considered to be responsible for the extracellular death of neurons. Because of their amyloid structure, these A can aggregate other proteins by polymerization, thus increasing their size, and spontaneously form a nucleus of A proteins of a given size. All this work revolves around the estimation of the nucleation rate, which is not experimentally accessible. This estimation is made by techniques related to the solution of inverse problems or optimal control problems. We discuss, interpret and numerically simulate the results obtained
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