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Landslide volumes and landslide mobilization rates in Umbria, central Italy
No full textA catalogue of 677 landslides of the slide type was selected from a global database of geometrical measurements of individual landslides, including landslide area (AL) and volume (VL). The measurements were used to establish an empirical relationship to link AL (in m2) to VL (in m3). The relationship takes the form of a power law with a scaling exponent α = 1.450, covers eight orders of magnitude of AL and twelve orders of magnitude of VL, and is in general agreement with existing relationships published in the literature. The reduced scatter of the experiential data around the dependency line, and the fact that the considered landslides occurred in multiple physiographic and climatic environments and were caused by different triggers, indicate that the relationship between VL and AL is largely independent of the physiographical setting. The new relationship was used to determine the volume of individual landslides of the slide type in the Collazzone area, central Italy, a 78.9 km2 area for which a multi-temporal landslide inventory covering the 69-year period from 1937 to 2005 is available. In the observation period, the total volume of landslide material was VLT = 4.78 × 107 m3, corresponding to an average rate of landslide mobilization φL = 8.8 mm yr− 1. Exploiting the temporal information in the landslide inventory, the volume of material produced during different periods by new and reactivated landslides was singled out. The wet period from 1937 to 1941 was recognized as an episode of accelerated landslide production. During this 5-year period, approximately 45% of the total landslide material inventoried in the Collazzone area was produced, corresponding to an average rate of landslide mobilization φL = 54 mm yr− 1, six times higher than the long term rate. The volume of landslide material in an event or period was used as a proxy for the magnitude of the event or period, defined as the logarithm (base 10) of the total landslide volume produced during the event, or period. With this respect, the new relationship to link AL and VL is a starting point for the adoption of a quantitative, process based landslide magnitude scale for landslide events
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
A new landslide area-to-volume relationship, and its application to the evaluation of landslide volumes and to the evaluation of landslide volume rates.
No full textLandslides are complex phenomena influenced by multiple factors. Knowing the number, area, and volume of landslides is important to determine landslide hazard and risk and to evaluate the long-term evolution of landscapes dominated by mass-wasting processes. The number and area of individual landslides and the total landslide area in a region can be computed from accurate digital landslide inventory maps. Determining the volume of a landslide is a more difficult task that requires information on the surface geometry of the slope failure. Determining the volume of slope failures for large populations of landslides is an even more difficult task that can be achieved adopting empirical relationships to link the volume of individual landslides to geometrical measures of the landslides. A catalogue of 677 mass movements of the slide type, from a global database of geometrical measurements of individual landslides, including landslide area (AL) and volume (VL), were used to determine a relationship linking landslide area to landslide volume. The relationship takes the form of a power law with a scaling exponent α = 1.450. We exploited the relationship to evaluate the volume of landslide material produced in the Collazzone area, Central Italy, in the period from about 1937 to 2005. The study area extends for 78.9 square kilometres, and a detailed multi-temporal landslide inventory map of the area, covering the period 1937-2005, shows 2543 landslides, for a total mapped landslide area of 10.43*106 m2. Using the landslide information and the area-to-volume relationship, we calculated the volume of the single landslides, we evaluated the total volume of landslide material and the average rate of landslide mobilization and we exploited the temporal information in the landslide inventory to estimate the volume of material produced during different periods by new and reactivated landslides
Variations on the Author
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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