1,720,961 research outputs found
Estimation of the impact probability in domino effects due to the projection of fragments
No full textDespite the remarkable severity of domino effects in activities at major hazard, a complete methodology analysing such events has not been developed and integrated within Quantitative Risk Analysis (QRA). Such a deficiency appears to be particularly remarkable for domino effects triggered by the projection of fragments. The aim of the present work is therefore to propose a systematic procedure for the quantification of domino effects due to fragments projection within QRA. To achieve this objective, the deterministic approach for the estimation of the realistic trajectory of fragments is entirely reviewed. In order to incorporate such a reviewed approach within the standard QRA, a probabilistic model for the impact probability of the fragments is developed by applying a Monte-Carlo method to the trajectory equations. The validation of the proposed framework is carried out by using the data related to an accident occurred in 1993 in the oil refinery of Milazzo (Italy). (C) 2014 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved
Risk management of road and rail transport of hazardous materials in Sicily
No full textA Transportation Risk Analysis (TRA) tool has been used to accurately assess the risk associated to a variety of road and rail transportation cases representative of hazardous materials transport by land in Sicily. Due to the high risk level, some risk mitigation options have been investigated: the possibility of changing route and/or transport modalities have been examined for each transportation activity, all the combinations of road, rail and intermodal (roadCrail) transport have been calculated and that minimising the risk has been identified with the aid of the TRA tool
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
Monitoraggio e gestione dei meccanismi di deterioramento di attrezzature in pressione attraverso un approccio ontologico
No full textLe attrezzature industriali in pressione, destinate al contenimento o alla conversione di
sostanze pericolose, e i loro componenti sono soggetti a fenomeni di invecchiamento che,
nel corso del tempo, possono influenzare i livelli di sicurezza dell’intero stabilimento in
quanto aumentano il rischio di perdita di contenimento e riducono la performance dell’intero
impianto. L’invecchiamento si manifesta come una forma generale di degrado del
componente, che non è associata solo al tempo in servizio ma alla sua condizione e a come
esso cambia nel corso del tempo. I meccanismi più comuni, con cui le attrezzature
deteriorano, rappresentano una percentuale significativa di guasti e di sostituzioni di
componenti. Tuttavia, il deterioramento si verifica anche a causa di molti altri fattori associati
ad aspetti di progettazione, di gestione, etc. La conoscenza dei meccanismi con cui avviene
il fenomeno (ovvero delle relazioni “causa-effetto”, “condizioni al contorno-velocità di
propagazione” ed “identificazione-misura”) e delle misure di prevenzione sono utili al fine di
monitorare il deterioramento delle attrezzature e di attuare una gestione sicura del
fenomeno. In questo articolo, si propone un approccio di esplorazione di tali relazioni basato
su una interpretazione ontologica dei meccanismi di deterioramento, con l'obiettivo di
supportare il monitoraggio dell’invecchiamento di attrezzature e componenti industriali. Per
raggiungere l'obiettivo, l'approccio proposto utilizza i concetti e le relazioni già definite per i
più comuni meccanismi, cui sono soggetti le attrezzature, all’interno della pratica americana
API 581. Detti meccanismi verranno definiti attraverso dei domini ontologici
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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