1,721,004 research outputs found
Esperienze nell’applicazione di tecniche “compression pre-cracking” per prove di propagazione frattura
No full textConsiderando tecniche di progettazione moderne quali la “Damage Tolerance”, la caratterizzazione delle curve di propagazione è uno degli elementi fondamentali, per la valutazione e la progettazione dell’integrità strutturale dei componenti in servizio, insieme alla performance dei controlli non distruttivi e alla determinazione dei carichi di esercizio. La zona della soglia di propagazione risulta poi particolarmente critica in quanto è lecito pensare che la maggior parte della vita di un componente avvenga nel suo ambito.
Recentemente, è stato però dimostrato che le metodologie tradizionali per la determinazione della soglia di propagazione, quali il “K-decreasing” e il “Kmax=const.”, influenzano il risultato in maniera non conservativa, ovvero possono produrre soglie di propagazione più alte di quelle naturali del materiale. E’ quindi stata proposta una metodologia innovativa basata sulla pre-criccatura in compressione. Tale tecnica, data la sua recente introduzione, è stata finora applicata a pochi casi applicativi. I materiali considerati ad oggi sono le leghe di alluminio, le leghe di titanio e gli acciai ad alta resistenza sollecitati mediante geometrie M(T) e C(T) e a rapporti di ciclo positivi.
La presente memoria si è quindi incentrata nell’applicazione della metodologia innovativa all’acciaio dolce strutturale A1N (tipicamente utilizzato per produrre assili ferroviari) in forma di provini SE(B) sollecitati da un ampio raggio di rapporti di ciclo tra R=-2 e R=0.85
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
L'INTERVENTO PUBBLICO IN AGRICOLTURA ATTRAVERSO GLI OBIETTIVI 1 E 5B: STRUMENTI PER UNA MAGGIORE COMPETITIVITA' DELLE AREE MEDITERRANEE
No full textD. REGAZZI (A CURA DI) L'AGRICOLTURA ITALIANA TRA PROSPETTIVA CONTINENTALE E MEDITERRANE
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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