1,721,058 research outputs found
Simplified model for the evaluation of the effects of explosions on industrial target
Full text linkThe evaluation of vulnerability of process equipment to explosion is a central issue in the analysis of industrial risks. In this work, we have developed a simplified model, however based on fundamental equations, which includes structural and fluid-dynamic parameters for the target (the industrial equipment) and for the impacting pressure wave (shock waves) or object (fragment, debris) produced by different type of chemical explosions.The validity of methodology has been assessed by case histories. Several insights on the dynamic of structural interaction of the explosion with the target have been obtained, with specific reference to escalation effects.The model derives from the well-known Johnson's number, often adopted in impact engineering. © 2015 Elsevier Ltd
A preliminary analysis of volcanic Na-Tech risks in the Vesuvius area
No full textThe area surrounding Vesuvius is considered as one of the most hazardous zone in the world. Several civil protection actions (prediction and prevention, emergency plans, evacuation plan) have been managed for the population but, quite surprisingly, industrial risks triggered by the interaction with this catastrophic natural event have been neglected (Na-Tech risks). Furthermore, Naples and its province have several industrial areas, two industrial harbors with LPG and fuel docks, and large fiiel storage plants, in the close surrounding of crowded suburbs. The analysis of volcanic Na-Tech risks presented in the paper shows a revised event tree starting from simplification of geophysicist studies, taking into account only the possible interaction with industrial equipment. Among the eruption phenomena (tephra fall, lava flows, pyroclastic flows and surges, atmospheric phenomena, pyroclastic bombs) the tephra fall has been analyzed in the following, starting from the intensity of explosive eruption predicted by Italian Civil Protection. ©2009 Taylor & Francis Group
Comparison of the explosion thermodynamics of TNT and black powder using le chatelier diagrams
Full text linkLe Chatelier diagrams may be adopted for the definition of thermodynamic loci of explosion in terms of internal energy with respect to the temperature for either the primary explosion or for the deflagrative, post-combustion of the products of the first reaction with air, the afterburning reaction. In this paper, Le Chatelier diagrams are produced for TNT and black powder by using the CEA code. Pressure plots with respect to density or air/fuel ratio are also shown. These results are useful for the simulation of explosion (hydrodynamic codes), and more generally for the definition of safety of storage, transportation, and production of explosives and pyrotechnics. Furthermore, the method can be easily extended to any deflagrative pyrotechnic substances, for which information on explosion and afterburning effects are needed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Green house gas emissions from oil and natural gas production
No full textThe No Risk No Energy (NRNE) project, supported by the Italian Ministry of Economic Develop- del Rischio Ambientale, Napoli, Italy ment - Directorate General for Safety, intends to develop a quantitative methodology to assess environmental, economic and social impacts deriving from the exploitation of energy resources by taking into account geographical and social peculiarities of the exploitation site. In this paper, we specify the models used to estimate greenhouse gas emissions from oil and gas operations and we present their application to fictitious fields approximating real Italian oil and gas fields. We identified OPGEE as the ideal model to estimate greenhouse gas emissions from oil operations and we implemented a model based on NETL libraries to estimate emissions from natural gas production. Model boundaries are Well to Refinery Gate for oil and Well to Tank for natural gas. Sensitivity to selected input parameters is also presented
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
The risk of storage plant of pyrotechnics
No full textRecent updating of Seveso Directive have made mandatory safety report of storage plants of pyrotechnics (fireworks). However, few guidelines are published in the open literature. The following work deals with the determination of maximum explosion pressures in confined and vented enclosures containing hazardous substances ranging from high-energy explosives to low-energy pyrotechnics. Copyright © 2010, AIDIC Servizi S.r.l
Case Study Application III: RISKCURVES
No full textThis chapter discusses the application of TNO's software packages RISKCURVES and EFFECTS in the quantitative Natech risk analysis of a refinery located on the Mediterranean coast. In addition to conventional industrial accident scenarios that could lead to a release of dangerous substances, the impact of two natural hazards (earthquake and tsunami) on the overall risk level was also considered and the priority risk contributors identified. © 2017 Elsevier Inc. All rights reserved
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