1,720,959 research outputs found
Monitoring of the movements of a deep, slow, clayey landslide and 3D interpretation
No full textThe Costa della Gaveta landslide is an active, deep
and very slow landslide which is being monitored and
studied since 2004. Recently new boreholes have been
carried out and inclinometer tubes have been installed
to deepen the comprehension of the 3D geometry and
kinematics. Localized displacement on a slip surface is
confirmed to be the prevailing movement mechanism.
Thanks to the long term monitoring, even the slow internal
viscous deformations of the landslide body have
been evaluated and interpreted. Soil discharge (i.e., the
volume rate of soil crossing transversal sections) is confirmed
to be constant in the track. This characterizing
kinematic feature allows a first approximation prediction
of the landslide behaviour on empirical basis.
To further improve the prediction of the landslide
behaviour and the risk management of the area, a
theoretical model has been constructed by a 3D finite
element code. First results show the large difference in
the safety factor between 2D and 3D analyses for the
considered landslide. The influence of pore pressure
distribution on the local safety factor is also analysed
Analisi degli spostamenti di una frana lenta in argille consistenti
Get PDFAllo scopo di ricostruire il campo delle velocità di spostamento di una frana molto lenta che si sviluppa alle porte della città di Potenza in formazioni strutturalmente complesse, è stata recentemente eseguita
una campagna di indagini geotecniche ad integrazione di indagini già eseguite nel passato. Sono stati realizzati due nuovi fori a carotaggio continuo, grazie ai quali è stato possibile esaminare la mesostruttura del materiale, determinare l’andamento del contenuto d’acqua con la profondità, installare tubi inclinometrici. Lungo la strada che attraversa la parte alta della frana sono state inoltre eseguite misure topografiche per la valutazione degli spostamenti in superficie.
I risultati dell’indagine confermano le ipotesi formulate da Di Maio et al. (2010) sulla geometria della superficie di scorrimento e sulla distribuzione delle velocità di scorrimento ed evidenziano l’esistenza
di uno strato superficiale di terreno ammorbidito, con contenuto d’acqua notevolmente più elevato di quello del terreno sottostante. La superficie di scorrimento si sviluppa in parte nel materiale ammorbidito ed in parte in quello più consistente
Influence of 3D geometry and pore pressure distribution on the safety factor of a deep earthslide in a clay slope.
No full textThis paper reports the results of 2D and 3D theoretical analyses of pore pressure
distribution and safety factor of a clayey landslide. 2D FEM analysis was carried out on the transient
process between limit hydraulic conditions of null flux and null pore pressure on the ground surface
(corresponding to dry and rainy weather respectively). The effects of the historical rainfall series of the site were also considered. Due to the very low hydraulic conductivity and to the significant
depth of the slip surface, the 2D analysis provides negligible pore pressure variations due to rain in the axial section. The influence of rainfall on 2D results gradually increases in the lateral sections, as the slip surface approaches the ground surface. The analyses carried out by means of the two
codes PLAXIS3D and STAB3D show a large difference of the safety factor with respect to the
value obtained by the 2D analysis. The influence of the landslid
Analysis of interaction between waves and cliff along the Adriatic cost of Polignano (Apulia, Italy)
Get PDFThe aim of this study is the analysis of the dynamic behavior of rocky cliff located below
the old urban center of Polignano (Apulia, Southern Italy). In order to characterize the behavior
of the cliff under the impulse generated by sea waves, two types of measures were carried out on
the rocky mass: (1) environmental vibrations and (2) accelerometer records. The first type of
measures, which may be executed in a short time with a high spatial density, has provided a
recognition of the different types of dynamic behavior of the cliff.
The accelerometer records, carried out during heavy storms in December 2009 and
January 2010, have been allowed to confirm the results of previous measures and to evaluate the
energy transfer from waves to cliff, in terms of maximum values and temporal distribution.
In order to facilitate a correct interpretation of measures, geological surveys for studying
fracturation of rocky mass were carried out.
The main results were the following:
1. The cliff shows a subdivision into two zones: (a) with stable behavior and without
amplification of wave impulse, characteristic of limestones, (b) with amplification of
wave impulse along several preferential directions, some of which are substantially
coincident with the directions of main systems of fractures, while others coincide with
local orientation of the rocky cliff.
2. The accelerometer measures confirm the different behavior. The most stable and less
fractured zone is crossed by the energy transmitted from waves to cliff without giving its
own contributions, the other zone filters this energy with its own frequencies.
3. The accelerations recorded (with maximum value of about 0.02 g) on the cliff during
storms show a regular distribution of observed values; this distribution can be correlated
with the wave height offshore
Microzonation of Potenza (Southern Italy) in terms of spectral intensity ratio using joint analysis of earthquakes and ambient noise
No full text
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
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
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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