1,720,990 research outputs found
Temperature in the Geothermal Euganean Basin: a Simulated Annealing Approach
No full textExtended Abstrac
Geostatistical analysis and mapping in a ground water pollution phenomenon in the area of Padova, NE Italy
No full textFirenze, Abstrac
A geostatistical simulation approach to a pollution case in Northeastern Italy
No full textThe study zone is located in the city of Padova (the Veneto region, NE Italy). The industrial activities
present in this area since 1950 have produced very high concentrations of Pb, Zn, Cu, Pcb and oils until
a depth of 7m. The unsaturated and the saturated zones are both polluted. Because of the abundance
of Pb values it was decided to analyze the lead distribution in the studied zone. In many studies of
the polluted sites, the geometry of the investigated volume is highly anisotropic. Generally we have
an extension of some hectares in the horizontal plane and of a few meters in depth. It is likely that
different horizontal spatial continuity structures in pollution distribution are found at different depths
both for the layered nature of the medium and for the transition between unsaturated and saturated
conditions. In such conditions the decision to divide a 3D problem into 1D and 2D problems can
be useful. Initially the studied volume was divided into seven layers up to 5m in depth; the study
was then approached in two phases. First, the Pb values in the vertical direction were analyzed,
considering a derive along z, and estimating the values using the Kriging with Trend (KT) method.
Thus it was possible to increase the data in the z direction, especially in the deeper layers. Second,
500 realizations of the Pb distribution for each of the seven layers were simulated using the simulated
annealing procedure. Finally, results were presented and discussed for each layer in terms of median
and probability map
Multisensor surveys of historical buildings before, during and after a seismic sequence: the leaning bell tower of Ficarolo (Rovigo)
No full textThree regions of Northern Italy (Emilia Romagna, Veneto and Lombardy) were struck in May-June 2012 by a
seismic sequence that included a moment magnitude 5.9 earthquake. Such a sequence caused significant damage
to several historical buildings; in some cases complete structural collapse occurred. The 69-m high bell tower of
Ficarolo (Rovigo province, Northern Italy) leans at a significant angle (3° in the shaft). Because the combination
of height and leaning angle is visually impressive, Ficarolo is also known as the “Pisa of Polesine” (Polesine is
the Venetian bank of the Po River), referring to the well-known 55-m high, 4° leaning tower of Pisa. A project
aimed at studying the geometry of the tower, by means of terrestrial laser scanning (TLS), possible local seismic
amplification and soil-structure interaction (SSI), by means of low-cost operational modal analysis (OMA) and
geophysical measurements, began in early 2012, before the earthquake. In particular, the first series of data were
taken in February 2012 (OMA) and April 2012 (TLS).
The distance from Ficarolo of the epicenters of the six events with moment magnitude higher than 5.0 ranged from
9 km to 37 km. Several cracks appeared in the bell tower belfry and cusp. An inclinometer installed in 2003 showed
that the base was unchanged, but the upper part of the shaft had moved by 2.5 cm after the main shock. No further
displacements were detected as a result of the aftershocks.
The repetition of the TLS and OMA surveys during and after the seismic sequence, together with infrared thermal
imaging (IRT) measurements, allowed an evaluation of the changes caused by the earthquake. Two main results
were obtained: (1) an estimate of earthquake induced damage to the Ficarolo’s bell tower, which were relatively
limited thanks to absence of SSI, and (2) it was demonstrated that fast measurements can be repeated during earthquake
emergencies and that preventive measures can be carried out under reasonable time and budget constraints
in high seismic hazard areas. The second point is particularly important from the viewpoint of cultural heritage
management purposes
Hacking the topographic ruggedness index
No full textThe topographic ruggedness index (TRI) is widely adopted for the analysis of digital elevation models, providing information on local surface spatial variability. In this work, the TRI is interpreted according to a geostatistical perspective, highlighting its main characteristics and drawbacks. TRI can be interpreted as an omnidirectional short-range spatial variability index, computed according to a pixel centered perspective. The simplicity and interpretability of the index, free from user-dependent selections, promoted its implementation in several software environments and its application in a wide set of case studies. However, the index has several drawbacks for its application in earth sciences, such as a strong dependency on local slope (it is basically an average adjacent neighbor slope algorithm) and the selection of different lag distances in the computation of spatial variability along the main directions and the diagonal ones. We propose a new metric radial roughness index (RRI) in order to solve the main drawbacks of TRI but maintaining its main philosophy (i.e., pixel centered perspective and simplicity of the algorithm). The new index corrects for the differences in lag distances and resolves the dependency on trend using increments of order 2. The code of the index, implemented in R statistical language, and test data are provided with the paper (https://doi.org/10.5281/zenodo.7132160) to promote its implementation in other software environments
Diachronic Mapping of Soil Organic Matter in Eastern Croatia Croplands
Full text linkThe spatiotemporal analysis and mapping of soil organic matter (SOM) play a pivotal role for evaluating soil health and for implementing preservation and restoration actions. In this context, the first aim of the study is to furnish a high-resolution mapping of current SOM content in eastern Croatia. The second aim is to perform a diachronic analysis of SOM content, comparing two datasets characterized by an extreme data imbalance. The more recent dataset (SOM2010), representative of 2010s, comprises 19,386 samples and the older dataset (SOM1970), representative of the 1970s, comprises 152 samples. The marked data imbalance and the different modalities in soil sampling and laboratory analysis of the two datasets are taken into consideration in performing the comparison. The study reveals a general depletion trend of SOM from the 1970s to the 2010s, more evident in with regard to Fluvisols and Gleysols. At a regional scale, the SOM2010 is characterized by lower variability compared to SOM1970, indicating a process of homogenization of SOM spatial distribution in recent years. Considering the local scale, there is limited information for the 1970s; for the 2010s the SOM spatial distribution is characterized by a high short-range spatial variability, with a characteristic spotty appearance, likely related to agricultural practices
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
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