1,720,988 research outputs found
REFINEMENT OF SEEPAGE VULNERABILITY ESTIMATE IN NATIONAL LEVEE DATABASE OF ITALY
Piping induced by seepage is a frequent cause of failure for earthen levees. The probability that the seepage line in the levee body intercepts the landside slope provides an important indication of the levee vulnerability to seepage. Nevertheless, the definition of the seepage paths associated to assigned water levels is affected by the difficulty in estimating the hydraulic parameters that control the filtration process, chiefly the soil hydraulic conductivity. The ideation of expeditious and operational methods, able to analyse extended levee systems quickly and to identify the most vulnerable portions of the systems, is therefore of paramount importance. To this purpose, an existing practical procedure for the evaluation of levee vulnerability to seepage, based on the definition of a vulnerability index (Camici et al., 2015), is here enhanced and it is used to produce 'synthetic diagrams', easily applicable to derive the seepage probability of the dykes whose hydraulic conductivity is unknown. The procedure is applied for the Tiber River (central Italy) and the Tanaro River (northern Italy). The Italian levee database (DANTE) is briefly presented in the final part of the paper: it is conceived as a dynamic geospatial tool, addressed to collect all the available information on levee systems and to usefully support authorities involved in hydraulic risk mitigation
Modeling the Effects Induced by the Expected Climatic Trends on Landslide Activity at Large Scale
AbstractTraditionally, slope stability assessments are based on stationary expected extreme rainfalls, provided by the Intensity-Duration-Frequency curves. More recent approaches are based on projected rainfall scenarios, considering the expected climatic trends provided by General Circulation Models (GCMs). The projected rainfalls used in this study have been obtained by climate simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Different GCMs emission scenarios (Representative Concentration Pathways 2.6, 4.5, 8.5) and time horizons (e.g., 2010-2039; 2040-2069; 2070-2099) are analysed. In order to fill the scale gap between the spatial resolution of GCMs and the resolution required for impact studies, statistically downscaled climate projections provided by [1,2] are used as input into PG_TRIGRS [3] to predict the effect of climatic change on landslide activity. A hydrological basin located in the Umbria region of central Italy is used as case study
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Dispelling the Myths Behind First-author Citation Counts
We 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
We 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
Levee body seepage: a refinement of an expeditious procedure for fragility curves and vulnerability diagrams' assessment
Extensive flooding can be the result of levee system failures most frequently caused by the piping process due to seepage. The proper description of the seepage line is affected by the difficulty of estimating the hydraulic parameters, mainly the soil hydraulic conductivity. Therefore, the development of simple methods for a quick analysis of extended levee systems is fundamental to identify critical points. In this context, a practical procedure, recently proposed, based on a simple vulnerability index is here enhanced and used to derive diagrams easily applicable for seepage vulnerability estimate, taking the hydraulic parameters' uncertainty into account. The procedure is applied for the Tiber River, in central Italy, and the Tanaro River, in northern Italy, by analyzing 67 and 6 levees, respectively. The results show that the method provides the highest seepage probabilities for levees affected by failures in the past. Therefore, the procedure seems to be able to identify the levees that require detailed investigations. Finally, the Italian levee database (DANTE) is presented as a dynamic geospatial tool for collecting all the available data/information on levee systems to usefully support authorities with the charge of hydraulic risk mitigation for identifying the most vulnerable levees
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