1,720,956 research outputs found
odelli digitali del terreno (DTM) ad alta risoluzione per il monitoraggio dei ghiacciai alpini – Digital Terrain Models of a high resolution for monitoring alpine glaciers
No full textThe aim of the research is the 3D reconstruction of a glacier surface thr ough the use of satellite stereoscopic images and Geographic al Information Systems (GIS). Th e project ‘s doubl e goal is to improve Digital Terrain Mod el (DTM) extraction techniques in morphologically highlycomplex areas and to obtain a high resolution DTM for studying, monitoring, and quant ifying the glacial resource. The ext raction of the high- resolution glacial surface DTM faces different challenges due to the ext reme physical variability of the surface. Glacier ice is a continuously moving deformable material that can locally genera te morphologically complex structures such as seracs and crevasses. These features show a seasonal variability linked to meteorological condi tions. An additional reason of compl exity is the presen ce of debri s (surface moraines) and snow cover: they can apparently alter the spatial shape of the glacier as well as its own elevation. The aim of the research is to identi fy a fast. .reproducible, and reliable method to support the traditional glacier survey and moni toring techniques. From the technolo gical point of view, we also want to verify the chances offered by new remote sensing acquisition systems and relevant elaboration software. Thi s first pa rt of the research has been of value in proving the reliability of the aerial and satellite images plane/ elevation data elaboration system, in checking the acquisition difficulties and costs, and in testing the utilization limits of the remote sensed data
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
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
Fluorine in the rocks and sediments of volcanic areas in central Italy: total content, enrichment and leaching processes and a hypothesis on the vulnerability of the related aquifers
No full textRock, sediment and water samples from areas characterised by hydrothermal alterations in the Sabatini and Vico Volcanic Districts, near Rome and the large city of Viterbo, respectively, were collected and analysed to determine the total fluorine (F) content and to understand the F geochemical back-ground level in the volcanic districts of central Italy.
Leaching and alteration processes controlling the high concentration of F in water were also investigated.
Fluorine concentrations were directly determined
(potentiometrically) by an F selective electrode in
water samples, while the procedure for rock samples included preliminary F dissolution through alkaline
fusion. F concentrations higher than 800 mg kg−1 were commonly found in the analysed rocks and sediments; the concentration depended on the lithology and on the distance from the alteration areas. A specific successive sampling campaign was con ducted in three areas where the F content in sediments
was particularly high; in the same areas, measurements of CO2 flux were also performed to investigate
the possible deep origin of F. To verify the relation
ship among the high F contents in rocks and
sediments, the leaching processes involved and the
presence of F in the aquifer, we also collected water
samples in the western sector of the Sabatini Volcanic
District, where hydrothermal manifestations and
mineral springs are common. The data were processed 40
using a GIS system in which the F distribution was
combined with morphological and geological observations. The main results of our study are that (1) F concentrations are higher in volcanic and recently formed travertine (especially in hydrothermally altered sediments) than in sedimentary rocks and
decrease with distance from hydrothermal alteration areas, (2) F is more easily leached from hydrother-
mally altered rocks and from travertine and (3) sediments enriched with F may indicate the presence of deep regional fractures that represent direct path- ways of hydrothermal fluids from the crust to the surface
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
Analysis of the spread of Rhynchophorus ferrugineus in an urban area, using GIS techniques: a study case in Central Italy
No full textThe spread of the red palm weevil is now a very severe problem on a global scale. In this paper, we investigate its spread during the 2007–2013 period in a coastal urban area characterized by a high density of palm trees, and discuss the application of a new approach to data collection and processing. While most works on the spread of the red palm weevil are based upon geo-referenced traps, we focused on the health of each palm, considering the surrounding territorial context. To this end, we used historical aerial photos, freely available remote sensing images and field surveys, integrated in a GIS environment to analyze the extent and mode of pest spread over time. Our results show that the exponential increase of new cases for each new year is regulated by this spatial spread model: at the early stage of infestation the red weevil tends to occupy as much space as possible, within the limitations of the distance it can fly; in the following stage, its infestation density increases in recently colonized areas. We discuss current local management of palm trees and the pests, and propose strategies that take into account both the ecology of the red weevil and the territorial context. Finally, we encourage the provision of more resources for early detection and prevention measures, as well as replacement of the dead Phoenix canariensis palms with a greater variety of species, as a varied composition would be less prone to pest-caused depopulation
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
- …
