1,721,284 research outputs found
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
La successione paleogenica epiligure della val Secchia (Appennino Settentrionale): biostratigrafia a foraminiferi planctonici e paleobatimetrie
No full textDepositional Systems And Architecture Of Oligo-Miocenic Turbiditic Successions In Cilento
No full textLate Eocene to Oligocene Calcareous Biostratigraphy in the Northern Apennines Satellite Basins: The Ranzano Sandstone.
No full textThe abundance distribution patterns of selected calcareous nannofossils were investigated by means of quantitative methods in the late Eocene to early Oligocene Ranzano Sandstone (RS, Epiligurian Succession) outcropping in the Northern Apennines. Our goals were 1) to test the reliability, in the terrigenous sediments of the RS, of the biohorizons used in the standard zonations of Martini (1971) and Okada and Bukry (1980) and of others recently proposed in the literature, 2) to establish biostratigraphic correlation within the RS on a regional scale, 3) to establish a chronology of the depositional history of the RS on the basis of calcareous nannofossil biostratigraphy, focusing on the main changes in facies and petrofacies described by Cibin (1993), Martelli et al. (1993), Cibin et al. (in press) and Mutti et al. (1995), and 4) to evaluate the regional and global significante of major stratigraphic esenta identified by previous studies. The standard zonations of Martini (1971) and Okada and Bukrv (1980) provide low resolution in this time interval. Wc suggest that sine calcareous nannofossil biohorizons are fairly reliable for classifying and correlating the stratigraphic record of the Northern Apennines from the uppermost Eocene to the topmost lower Oligocene. On the basis of these biohorizons, we have proposed a set of six biozones wihich have been tentatively correlated to the global standard chronostratigraphic scale. The provided time resolution is high in the latest Eocene and basal Oligocene (less than 1.0 m.y.) and low in the advanced early Oligocene. On the basis of the calcareous nannofossil biochronology developed, it has been possible to establish a chronology of the depositional history of the Ranzano Sandstone which was unavailable so far. The RS outcropping between the eastern Tertiary Piedmont Basin and the Enza Valley (Reggio Emilia Province) is terminal Priabonian (upper Eocene) to the terminal Rupelian (lower Oligocene) in age and covers a time interval of 4-6 m.y. The calcareous nannofossil biostratigraphy provides a time grid which allows the recognition, correlation and timing of the main stratigraphic events indicated by field stratigraphic analysis, and the evaluation of their degree of synchroneity on a regional scale. This is important because the RS shows a high degree of stratigraphic variability which prevents the tracing of physical stratigraphic correlation among the various outcrop areas. Finally, the availability of a global time frame allows comparison of the local stratigraphic history with the global glacioeustatic record suggested by oxygen isotope stratigraphy, thus contributing to the ongoing harsh debate on the tuie of tectonics versus eustasy in stratigraphy. Tettonics is the dominant factor in determining the stratigraphic architecture of the RS. Some of the events which characterize the RS (the base of the unit, the beginning of the supply of ophiolitic detritus, a widespread hiatus at the Eocene-Oligocene boundary) are reasonably synchronous in the investigated area. This finding suggests that, if tectonics were the dominant causative mechanism in determining these features, tectonics must have been operating at a regional scale, and, most probably, at a very fast rate. However, there is good matching between the timing of the above mentioned widespread basal Oligocene erosional event (Valle dei Cavalieri event) and a major oxygen isotope shift (Oi1 of Miller et al., 1991a, 1996) which may support the hypothesis of eustatic control over the development of this stratigraphic feature. The other major events recognized in the RS Succession are not sufficiently constrained in time to allow, a confident correlation to the oxygen isotope stratigraphy. However, two regional chaotic mass wasting events (Specchio and Zermagnone events) and a confined thick bedded coarse grained turbiditic body (Lagrimone Sandstone) could be tentatively, linked to eustatic lowering suggested by oxygen isotope stratigraphy. This would suggest that, even in an active tectonic setting like that of the RS, eustasy is a major factor in controlling sedimentation
The exoskeleton: A solution for seismic retrofitting of existing buildings
Full text linkAn exoskeleton is an external steel self-supporting system rigidly linked to an existing building that need to be safeguarded against seismic actions in order to comply with the current technical standards. Its application can guarantee an innovative seismic adjustment that combines structural and safety goals with sustainable properties. The present study deals with the performances of the developed coupled system under seismic actions when a suitable exoskeleton structure is applied to a real construction. It is designed with an in-plane rigid behaviour at each floor and a non-dissipative rigid link connects the primary building to the external structure. Early descriptions of the inner and the external constructions forerun the dynamic analysis, which allows to understand seismic response of the system especially in terms of frequencies and periods of vibration, floor displacements, stiffness and shear forces. Ensuing outcomes highlight the capability the exoskeleton has in taking base and floor shear forces as well as in reducing displacements and deformations of the primary building, so that it is protected from a potential earthquake collapse
Foraminiferal biostratigraphical and paleobathymetric constraints in geohistory analysis: the example of the Epiligurian Succession of the Secchia Valley (Northern Apennines, Mid Eocene-Late Miocene)
No full textABSTRACT
A geohistory analysis has been proposed for the Mid Eocene-
Late Miocene Epiliguran succession cropping out in the Enza, Secchia
end Reno Valleys (Northern Apennines) in order to quantify the
evolution of the studied areas in terms of both vertical motions (subsidence/
uplift) and sedimentary infill. The three curves integrate and
complete the geohistory scenario proposed by DI GIULIO et alii
(2002) in order also to discriminate local events from large-scale
episodes related to the Northern Apennine orogenesis.
New biostratigraphic and paleobathymetric data were collected
for the late Bartonian-early Burdigalian Epiligurian succession from
the Secchia Valley, conversely, literature data have been used for the
youngest investigated units (Pantano, Cigarello and Termina Formations;
Burdigalian-Tortonian), which were not sampled for this
work. Both chronostratigraphic and bathymetric data have been
wholly derived from the literature for the Enza and Reno Valleys
(MANCIN & PIRINI, 2001; 2002).
From a paleobathymetric point of view, the Secchia Valley
Epiligurian deposition began in the earliest Bartonian in a very deep
marine environment (average depth 1900 m). After a deepening
phase during late Bartonian-Priabonian, with a shift of the bottom
(average depth 2200 m) to probably close to the calcite compensation
depth, an overall shallowing trend was recorded culminating in
Burdigalian shelf deposits (Pantano Fm., average depth 50 m).
Finally, during Mid-Late Miocene, a second, lesser, deepening phase
occurred, ending with the Tortonian sediments of the marly Termina
Fm. (average depth 200 m). This paleobathymetric evolution
has been related to the vertical motion and sedimentary infill undergone
by the Secchia Valley area during the time interval considered.
The results described highlight the occurrence of large-scale
episodes involving the whole analysed area (from the Enza to the
Reno Valleys), alternating with periods of quite different growth for
each sector recording the existence of independently evolving
domains of the Ligurian orogenic wedge in the geodynamic context
of a mobile belt
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
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