1,721,006 research outputs found
Archives scientifiques: Jacques Friedel
No full text« À l’université de Paris XI-Orsay, vient de s’achever, grâce à une étroite collaboration entre archivistes et scientifiques, le classement des archives personnelles de Jacques Friedel conservées au laboratoire de physique des solides (UMR 8502 du CNRS). Ces papiers qui comportent en particulier un ensemble très volumineux de correspondance témoignent non seulement de l’oeuvre scientifique de Jacques Friedel mais aussi de son implication dans l’organisation de l’enseignement et de la recherch..
Quel avenir pour la métallurgie française ?
No full textLa métallurgie est une science pluridisciplinaire originale, qui
emprunte ses outils à la physique, la mécanique et la chimie, tout en
en créant de nouveaux. Elle s’adosse à un secteur industriel puissant
qui, en France, représentait encore, en 2007, près de 1 800 000 emplois
dans 45 000 entreprises environ.
Les Académies des sciences et des technologies viennent de publier
un rapport sur l’état de la métallurgie (science, industrie et enseignement)
en France, pour alerter les pouvoirs publics et l’opinion
sur la situation inquiétante actuelle de cette discipline dans notre
pays. Ce rapport présente un ensemble de mesures à mettre en
oeuvre rapidement.
Jacques Friedel nous dresse ici un panorama de la métallurgie en
France dans une perspective historique, puis présente le rapport
des Académies.
Nous remercions Yves Bréchet qui est à l’initiative de cet article.
La rédactio
Disparition de Jacques Friedel - Un des derniers « pères fondateurs » de la métallurgie physique, et pionnier de la physique des solides, nous a quittés
No full textJacques Friedel nous a quittés le 27 août 2014 à Paris. Nous rappelons à grands traits l’importante
carrière et l’attachante personnalité de cet immense métallurgiste théoricien et spécialiste de la
structure électronique des solides
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
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
Dislocations and other topological oddities
Get PDFAbstractWe will show that the book Dislocations by Jacques Friedel, published half a century ago, can still be recommended, in agreement with the author's intention, as a textbook “for research students at University and for students at engineering schools as well as for research engineers”. Indeed, today dislocations are known to occur not only in solid crystals but also in many other systems discovered more recently such as colloidal crystals or liquid crystals having periodic structures. Moreover, the concept of dislocations is an excellent starting point for lectures on topological defects occurring in systems equipped with order parameters resulting from broken symmetries: disclinations in nematic or hexatic liquid crystals, dispirations in chiral smectics or disorientations in lyotropic liquid crystals. The discussion of dislocations in Blue Phases will give us an opportunity to call on mind Sir Charles Frank, friend of Jacques Friedel since his Bristol years, who called these ephemeral mesophases “topological oddities”. Being made of networks of disclinations, Blue Phases are similar to Twist Grain Boundary (TGB) smectic phases, which are made of networks of screw dislocations and whose existence was predicted by de Gennes in 1972 on the basis of the analogy between smectics and superconductors. We will stress that the book by Jacques Friedel contains seeds of this analogy
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
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