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Model-based approach for design and performance evaluation of works controlling stony debris flows with an application to a case study at Rovina di Cancia (Venetian Dolomites, Northeast Italy)
Full text linkThis paper proposes a methodology for the design and performance evaluation of debris-flow control works
based on modeling the phenomenon and its interaction with the works. The reliability of such an approach
depends on the trustworthy reproduction of both the phenomenon and its interaction with the structures:
the former is provided by simulating all the physical processes concerning the phenomenon (runoff gen-
eration, initiation and propagation of a solid-liquid mixture) by models tested against field measurements;
the latter by upgrading the propagation model for considering the non-erosive surfaces of the works over-
flowed or hit by debris flows and computing the forces exerted on them. This methodology is applied to a
case study on the Rovina di Cancia channel (northeast Italy), frequently affected by stony debris flows. Lon-
gitudinal and transversal works are planned in a reach of the channel subject to high erosion because of its
high slope and the supply of water discharge by the Bus de Diau Creek tributary. The works consist of a sec-
tional dam at the end of the reach and in moving there the mouth of the Bus de Diau Creek. Both of them
contribute to decrease bed erosion along the reach and to reduce the peak discharge and the transported
sediment volume. The proposed methodology is used in the design phase to explore different geometries of
the dam opening and choose its transversal position through the analysis of flow (velocity and free surface),
whereas, in the evaluation phase, to estimate the reduction in the bed erosion, peak discharge and trans-
ported sediment volume provided by the works (i.e. the performance evaluation). Finally, the plot of the
forces acting on the dam breakers and bottom over time allows their static dimensioning
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
Hydrologic response in the initiation area of the Dimai debris flow (Dolomites, Italian Alps)
No full textDebris flows are fast moving landslides of mixed water and poorly sorted debris (IVERSON, 1997; CRUDEN AND VARNES, 1996). Because of the high flow velocity, impact forces, and long runout, debris flows are commonly regarded as one of the most hazardous landslide types (JAKOB, 2005). The Dolomites region (NE Italian Alps) has one of the most frequent return intervals for large debris flows on the world (PASUTO AND SOLDATI, 2004; SKERMER AND VANDINE, 2005).
In the Dolomites the landscape is dominated by steep dolomite massifs rising up to 3300 m a.s.l. The rocky cliffs are connected to the bottom of alpine valleys by means of milder slopes where bedrock is covered by a thick debris talus, deposited in post-glacial climatic conditions. Debris flow channels are deeply incised in the talus slope and feeded by small headwater basins located on the cliffs (MARCHI AND TECCA, 1992; BERTI et alii, 199). These basins are typically very steep (45°-60° on the average) and mostly consist of exposed bedrock with no vegetation and almost absent soil cover.
During high intensity short duration thunderstorms, rainfall water is collected by the rocky watersheds as overland flow and trunk streams incised in bedrock, and quickly delivered to the talus cones. Most of this water infiltrates into the channel bed debris and flows downstream as subsurface stormflow. However, when the infiltration capacity of the streambed is exceeded, surface flow appears in the channel and debris flows are triggered by the progressive erosion of the loose bed debris (BERTI AND SIMONI, 2005).
Although this initiation mechanism has been widely recognized in the field (e.g. CANNON et alii, 2003), monitoring data describing the onset of channel runoff and the triggering process are still lacking. In this paper we describe the monitoring systems installed on a typical debris flow catchment of the Dolomites (Dimai basin, Cortina d’Ampezzo, Belluno), with the main aim of describing the hydrologic response in the initiation area
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
Relevance of erosion processes when modelling in-channel gravel debris flows for efficient hazard assessment
No full textA storm, composed of two delayed cells, hit the Monte Antelao slopes (Dolomites, North Eastern Italy) in the
early morning of July 18th, 2009. The resulting runoff triggered two consecutive debris flows along the Rovina
di Cancia channel. The detailed topographic data collected before and just after this event allowed an accurate
reconstruction of the morphological changes experienced by the channel bed. These data are here used as
benchmark to test the ability of numerical models to reproduce the dynamics of a real event, taking into account
the morphology changes of the channel bed. The aim is to provide an efficient model for engineering applica-
tions on large scales, such as those required by debris flow hazard assessment. A rainfall-runoff transformationis
applied to reconstruct the solid-liquid hydrograph needed for computing the debris flow propagation. Two
routing models are used: a GIS-based movable bed model, and a widely used fixed bed model (FLO-2D).
Although similar results are obtained in terms of areas subjected to deposition, significant differences emergein
terms of mobilized volumes. Only the simulation of both the deposition and entrainment processes allows to
reliably reproduce the sediment volumes estimated from the pre- and post-event topographic data. This in-
formation is fundamental in any hazard assessment because the volume of sediment mobilized by debris flow
events exerts a fundamental control on the extension of areas subjected to inundation and on the thickness of
sediment deposits. The capability to reproduce correctly the mobilized volumes also entails a more reliable
simulation of the evolution of the peak and volume of the solid-liquid hydrograph as the debris flow propagates
downstream, allowing the identification of the channel reach where banks could be overflowed. Conversely,
adopting a fixed bed model leads mainly to an underestimation of the both the transported sediments volumes
and the area subjected to deposition. As a consequence, the maximum debris flow depth in the portion of the
channel subjected to erosion is underestimated and that in the portion of the channel subjected to deposition is
overestimated. All these types of information are of great importance for an effective hazard assessment
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
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
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
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