1,720,956 research outputs found
STPA Based Approach for a Resilience Assessment at an Early Design Stage of a Cruise Ship
No full textSeveral definitions and approaches have been proposed to study resilience in different fields like materials, ecology, psychology and infrastructures. A general definition, applicable also to human-made or engineered systems, describes resilience as the ability to maintain capability in case of disruption.
Thanks to its systemic, top-down approach, STAMP (System-Theoretic Accident Model and Processes) has been already identified in literature as a very effective and “conductive” reference when reasoning about the possible need of resilience of a complex system. The STAMP-based tool named STPA (System Theoretic Process Analysis) establishes the following steps: identify system accidents, hazards; draw functional control structure; identify unsafe control actions (UCAs); identify accident scenarios; formulate decisions and recommendations. It focuses on what actually is in the hands of the system designer and operator i.e. the possibility to take action on hazards that can be eliminated or controlled.
In this paper an approach to design resilience into a cruise vessel will be proposed. An application case will be developed considering the specific hazard of dead ship condition i.e. of energy black-out on board. In case of navigation close to the shore and in heavy weather condition, this situation can rapidly evolve into a loss. The ship energy production and delivery system, both for the propulsion and for the hotel services, will be considered. Running the procedure up to the level of UCAs enables the identification of the possible disruptive events capable to degrade the operational performance of the system. Starting from this point, suggestions will be discussed for a selected UCA, able to prevent or mitigate it. A metric for ship resilience will be proposed as well with the aim to allow comparisons among different design solutions
HUMAN FACTOR AND AUTOMATION: A STPA APPRACH TO ENHANCE SHIP SAFETY
No full textShips complexity is continuously increasing and lots of action controls, traditionally carried out by crew members, are now managed and executed by the on-board automation systems. The relation among humans and automation system shall be studied with specific attention to their mutual interface and interaction issues, in order to better pursue safety. The STAMP (System-Theoretic Accident Model and Processes)-based tool named STPA (System Theoretic Process Analysis) consists the following steps: identify system hazards; draw functional control structure; identify unsafe control actions (UCAs); identify accident scenarios; formulate decisions and recommendations. In this paper an approach to model the relations among human operator and automation, based on STPA, will be proposed. An application case will be developed considering a large passenger ship and the specific hazard of dead ship condition (energy black-out). In case of navigation close to the shore and heavy weather condition, this situation can rapidly evolve into a ship loss
APPLICATION OF CAST to COSTA CONCORDIA ACCIDENT
No full textCAST (Causal Analysis based on Systems Theory) is used to rationally elicit the cause of Costa Concordia accident
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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