1,720,970 research outputs found
Le componenti biotiche
No full textVengono descritte le componenti biotiche in grado di colonizzare gli ambienti degradati oggetto dello studio, ponendo l'accento sugli adattamenti che permettono la sopravvivenza anche in ambienti più ostil
Restauro della Sala Capitolare della Canonica di Vigonza: caratterizzazione del legno.
No full textOggetto del lavoro è la caratterizzazione degli elementi lignei strutturali della Sala Capitolare dell’ex Convento della chiesa di S. Margherita in Vigonza, Padova, finalizzata al restauro della struttura.
Si è proceduto all’identificazione del legno costituente le colonne e il solaio. Le colonne sono risultate in due legni diversi, Quercus sp. la prima e Ulmus sp. la seconda, mentre il solaio è costituito da Picea abies.
Sono stati quantificati i difetti che possono influire sulla resistenza meccanica del materiale, tra i quali la deviazione della fibratura e i nodi.
È stato determinato il contenuto di umidità del legno, che è risultato inferiore al 20%, quindi al di sotto dei valori pericolosi per gli attacchi di funghi lignivori.
L’analisi del degrado biologico ha rivelato la presenza di insetti xilofagi, in particolare anobidi e cerambicidi sugli elementi di rovere, il cui attacco è ancora in atto.
Infine è stata effettuata la datazione dendrocronologica di alcuni elementi del solaio che sono risultati risalire al 1574.
Il restauro è stato guidato dalle informazioni desunte dalla caratterizzazione del materiale come raccomandato dalla recente norma UNI 11138: 2004
Bog oak: characteristics and characterization of two logs from the Venetian Plain
Full text linkThis work presents the characterization of two bog oak logs found in two rivers in the Veneto
countryside. One of the trunks dates back to around 400 AD, the other one to 1400 AD. The logs are free
of bark, with the black and cracked external surface with a charred appearance. On the inside, underneath the
more weathered layer, the wood appears intact, free of signs of apparent degradation, carbon black in color.
Going towards the internal parts of the trunk, the colour goes from black to natural brown of the intact wood.
The physical characterization (basal density, shrinkage and maximum water content) indicates that
degradation phenomena are also present in the apparently intact wood. Bacterial degradation was clearly
highlighted through microscopic analysis. From the analysis of the ash content, it seems that the increase
in the density of the apparently intact areas is due to the entry of inorganic material. The difference of about
a thousand years of stay in the basement site does not seem to have differentiated the physical parameters of
the two woods. Instead, the difference with the same parameters of the oak wood of a pirogue dating back to
800 AD is evident
Anatomical and physical characterization of DED resistant elm clones wood grown in Italy
No full textAim of this study was the technological characterisation of two elm clones resistant to DED.
Their characteristics were compared with those of field elm to explore if their wood is suitable to satisfy the high demand of elm wood in the European market, where it is lacking from several years because of the high losses of mature trees due to the disease
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
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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