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    Dynamic Slope Stability Analysis of Mine Tailing Deposits: the Case of Raibl Mine

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    Over the last few years, many embankments and levees have collapsed during strong earthquakes or floods. In the Friuli Venezia Giulia Region (North-Eastern Italy), the main source of this type of risk is a slag deposit of about 2x106m3 deriving from galena and lead mining activity until 1991 in the village of Raibl. For the final remedial action plan, several in situ tests were performed: five boreholes equipped with piezometers, four CPTE and some geophysical tests with different approaches (refraction, ReMi and HVSR). Laboratory tests were conducted on the collected samples: geotechnical classification, triaxial compression tests and constant head permeability tests in triaxial cell. Pressure plate tests were also done on unsaturated slag to evaluate the characteristic soil-water curve useful for transient seepage analysis. A seepage analysis was performed in order to obtain the maximum pore water pressures during the intense rainfall event which hit the area on 29th August 2003. The results highlight that the slag low permeability prevents the infiltration of rainwater, which instead seeps easily through the boundary levees built with coarse materials. For this reason pore water pressures inside the deposits are not particularly influenced by rainfall intensity and frequency. Seismic stability analysis was performed with both the pseudo-static method, coupled with Newmark’s method, and dynamic methods, using as design earthquake the one registered in Tolmezzo (Udine) on 6th May 1976. The low reduction of safety factors and the development of very small cumulative displacements show that the stability of embankments is assured even if an earthquake of magnitude 6.4 and a daily rainfall of 141.6mm occur at the same time

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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
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