1,721,064 research outputs found
Préface
No full textBouzou Moussa Ibrahim. Préface. In: Revue de géographie alpine, tome 92, n°1, 2004. De part et d'autre du Sahara, sous la direction de Ibrahim Bouzou-Moussa . pp. 5-6
Préface
No full textBouzou Moussa Ibrahim. Préface. In: Revue de géographie alpine, tome 92, n°1, 2004. De part et d'autre du Sahara, sous la direction de Ibrahim Bouzou-Moussa . pp. 5-6
Sur l'origine des karsts du bassin des lulliminden au Niger
No full textGenesis of the Iulliminden basin karst (Niger). The carbonated and cuirass areas of the lulliminden basin plateaus show many closed-in, circular or oval depressions. Though noticed early by geologists, they have been described only recently. These depressions are similar to the known karstic forms such as dolines, ouvalas and poljes. Some of them, such as the valleys with bayonet-shaped lines and the karst with residual hillocks, are typical. The lithologie differences that characterize these plateaus make it possible to make assumptions on the origin of these pseudo-karstic forms : dissolution of limestones, sandstones (Continental terminal) and weathered rocks of the basement, and withdrawing.La surface calcaire et cuirassée des plateaux du bassin des lulliminden au Niger présente de nombreuses dépressions fermées. Très tôt observées par des géologues, elles ne seront décrites que beaucoup plus tard. Elles sont similaires aux formes karstiques connues comme les dolines, ouvalas et poljés. D'autres sont spécifiques comme les vallées à tracé en baïonnette et le karst à buttes résiduelles en mamelons. Les différences lithologiques permettent d'émettre plusieurs hypothèses génétiques : dissolution dans les calcaires, les grès du Continental terminal et les altérites du socle, puis soutirage.Bouzou Moussa Ibrahim, Schoeneich Philippe. Sur l'origine des karsts du bassin des lulliminden au Niger. In: Karstologia : revue de karstologie et de spéléologie physique, n°31, 1er semestre 1998. Apports de l'endokarst dans la reconstitution morphogénique d'un karst (Antre de Vénus, Vercors) pp. 42-47
Valorisation des techniques anti-érosives traditionnelles en milieu sahélien : les micro-barrages en sacs de sable (Tahoua, Niger) / The development of traditional anti-erosion techniques in the Sahel : micro-dams made of sand bags (Tahoua, Niger)
No full textAbstract : In Niger, the struggle against erosion, which began in the 1960s, has mainly concerned muddy-clayey, clayey, and rocky soils, and has involved the use of heavy structures (small dykes, rockfill dams and gabions) which have met with varying degrees of success. On the sandy soils, however, much remains to be done. Thus, in 1993, in the Adar in west central Niger, an experiment was begun using micro dams made of sand bags. Improvements were made to single lines of sand bags based on the technique of gabion sills. The experiment was implemented at the scale of the individual plot, with farmers being chosen on the basis of their interest in the method. It remains to be seen whether this technique can provide a solution to the problem of gullying on the sandy soils, and whether the farmers would be able to adopt such a technique.ressé, avec plus ou moins de succès, les terrains limono-argileux, argileux, rocailleux avec comme techniques les ouvrages lourds (di- guettes, barrages en pierres sèches ou gabions...). Par contre pour les terrains sableux, il reste beaucoup à faire. Dans cette optique, à partir de 1993 a été entreprise l'expérimentation de la technique des micro-barrages en sacs de sable, dans l'Adar au centre-ouest du Niger ; de simples alignements de sacs de sable ont été améliorés en s'inspirant de la technique des seuils en gabions. L'échelle d'intervention a été la parcelle individuelle ; les agriculteurs ont été choisis en fonction de leur intérêt pour la méthode. Il s'agit donc de savoir si cette technique peut être une solution aux ravinements en terrains sableux, et si les agriculteurs peuvent se l'approprier.Bouzou Moussa Ibrahim. Valorisation des techniques anti-érosives traditionnelles en milieu sahélien : les micro-barrages en sacs de sable (Tahoua, Niger) / The development of traditional anti-erosion techniques in the Sahel : micro-dams made of sand bags (Tahoua, Niger). In: Revue de géographie alpine, tome 85, n°1, 1997. pp. 87-99
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
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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