1,720,977 research outputs found
Geotechnical characterization of a polluted marine basin
No full textThe work presents the results of an intense experimental research into the chemo-mechanical coupling phenomena involving the sediments from the Mar Piccolo basin (Taranto, South of Italy), severely contaminated by both heavy metals (e.g. Hg, Pb, Cd, Cu and Zn) and organic pollutants (PCBs, PAHs, and dioxins). Among the different matrices involved in the environmental studies, i.e. sediments, water and biota, this research focuses on the submarine sediments and reports the results of both the chemical and the geotechnical investigations carried out during the off-shore campaign, prompted by the Special Commissioner for urgent measures of reclamation, environmental improvement and redevelopment of Taranto.
Geotechnical tests were carried out on more than 50 samples, taken from up to 30 m below the seafloor. The standard equipment and procedures were properly adapted to take into account the influence of salt and organic compounds in the pore fluid. The geotechnical testing programme included tests aiming to characterise physical properties, composition and state of the sediments, oedometer tests to determine the 1D compression and consolidation properties of the soil and CIU triaxial tests for the measurements of both isotropic compressibility and strength. Furthermore, an apparatus was developed for both the squeezing of the sediment and the pore flid extraction of pore fluid during compression. Off-shore piezocone tests were also carried out and the results were used to interpret the stratigraphy and derive engineering properties of soils.
The integration of the geotechnical and chemical data allowed to investigate the effects of the chemo-mechanical interaction processes on the geotechnical behaviour of the sediments, in the light of the most relevant literature.
The Mar Piccolo represents a “natural laboratory” and an emblematic case in the worldwide panorama of polluted sites. Hence, the study offered the possibility to produce and analyse an uncommon coupled database of both geotechnical and chemical results concerning natural geomaterials altered by the presence of different sources of contamination
Geotechnical characterisation of submarine sediments from a polluted site
No full textThe present note discusses some laboratory complexities linked to the geotechnical characterization of the soft polluted sediments sampled down from the Mar Piccolo, i.e. a marine basin located within the urban area of Taranto (south of Italy), for which the environmental remediation has been identified as a national priority. The long-lasting industrial activities, together with the waste collection from the densely populated urban center of Taranto, have been responsible for the severe environmental contamination of the Mar Piccolo. In the field of the remediation and management strategies promoted by the Italian Government, a multidisciplinary investigation has been carried out to achieve the chemical, geological and geotechnical characterization of the sediment in the basin. With this purpose, the standard procedures and equipment for geotechnical testing were properly modified to both minimize the soil disturbance and to take account of the influence of both the pore fluid salinity and the presence of organic compounds, shells, mussels and lapideous elements or industrial waste in the soil
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
Marine Sediments from a Contaminated Site: Geotechnical Properties and Chemo-Mechanical Coupling Processes
Get PDFISSN:2076-326
Subsidence of Artificial Reefs with Bamboo Foundations on a Soft Seabed
Get PDFThe design of artificial reefs must be based on the criteria of both durability and serviceability. In this respect, the seabed subsidence rate related to the weight of the reefs and of their foundation system should be limited. The horizontal drift of the reefs during their life should be small too. In this study, pertaining to the behavior of artificial reefs made of microsilica concrete and realized with foundations in bamboo near the international airport of Hong Kong, 1-year monitoring data and calculations of reef foundation settlements are shown and discussed to assess the performance of the adopted mixed foundation and to deduce the nature of the long-term subsidence. The subsidence related to the settlements of the foundations was monitored using a Multibeam Echo Sounder System. It was found that the observed subsidence rate cannot be justified by the primary consolidation of the soils forming the seabed. Indeed, secondary consolidation seems to play an important role. Overall, after one year of service, the artificial reefs are considered to be effective in terms of limitation of both subsidence and drift
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
Effects of bio-chemo-mechanical processes on the properties of contaminated marine sediments
Get PDFISSN:0016-8505ISSN:1751-7656ISSN:1751-765
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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