1,721,930 research outputs found
Συγκριτική αξιολόγηση προτύπου ISO/DIS 12215-5.2 με κανονισμούς νηογνωμόνων
Get PDF275 σ.Αφορμή αυτής της διπλωματικής εργασίας είναι η είσοδος του διεθνούς οργανισμού τυποποίησης ISO στο χώρο τον κανονισμών για σκάφη από σύνθετα υλικά κάτω των 24 μέτρων με το πρότυπο ISO/DIS 12215-5.2 Hull construction – Scantlings – Part 5: Design pressures for monohulls, design stresses, scantlings determination, Date: 25-03-2004. Σκοπός της διπλωματικής εργασίας είναι να γίνει μια συγκριτική μελέτη και ανάλυση του κανονισμού ISO/DIS 12215-5.2 με τους ήδη υπάρχοντες κανονισμούς των νηογνωμόνων βάσει αποτελεσμάτων σε σκάφη. Στη συγκριτική αυτή μελέτη αρχικά θα γίνει παράθεση των εξισώσεων που προτείνει ο κάθε κανονισμός έτσι ώστε να φανούν οι διαφορές μεταξύ τους. Στη συνέχεια θα γίνει ανάλυση των εξισώσεων έτσι ώστε να βρεθούν οι αρχικές σχέσεις στις οποίες έχουν βασιστεί οι κανονισμοί καθώς και οι κρυμμένοι συντελεστές ασφάλειας και οι υποθέσεις για τις οριακές συνθήκες που χρησιμοποιεί ο κάθε ένας ξεχωριστά. Αυτό σε συνδυασμό με την εφαρμογή των κανονισμών σε συγκεκριμένα σκάφη θα μας δώσει μια γενική εικόνα της κατάστασης που υπάρχει στους κανονισμούς μικρών σκαφών από σύνθετα υλικά.The reason of this diploma thesis is the entrance of ΙΣΟ in the feald of class regulations for plastic vessels under 24 meters, with regulation ISO/DIS 12215-5.2 Hull construction – Scantlings – Part 5: Design pressures for monohulls, design stresses, scantlings determination, Date: 25-03-2004The reason of this diploma thesis is the entrance of ΙΣΟ in the feald of class regulations for plastic vessels under 24 meters, with regulation ISO/DIS 12215-5.2 Hull construction – Scantlings – Part 5: Design pressures for monohulls, design stresses, scantlings determination, Date: 25-03-2004Δημήτριος Α. Μπαλάφα
Structural analysis of composite search and rescue vessels under the new BS EN ISO 12215-5
Get PDFAmongst the new implementations to the forthcoming BS EN ISO 12215-5 features a workboat annex, namely Annex J. This will allow vessels in professional use, such as search and rescue crafts, to be designed under the updated regulation. Moreover, to account for the increasing design and operating speeds since the previous BS EN ISO 12215-5 published in 2008, the scope has been extended beyond 50 knots, while also accounting for higher accelerations. The technical background and practical applications of the new regulation for composite vessels will be presented, highlighting the increased factors of safety adopted to ensure reliability and account for the operating profile of the vessels
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Regulatory Developments in Structural Keel Design:A Revised ISO 12215-9
Get PDFThe design of yacht keel structures is governed by the ISO 12215-9:2012, which is concerned with the loads and scantlings of monohull sailing craft appendages up to 24 m hull length. However, the significant advances in sailing yacht performance, appendages design, materials and manufacturing of the past decade now warrant a revision of this crucial international standard. Consequently, this paper presents the technical background and impending developments in regulatory yacht keel structures. The proposed revisions include (i) a new load case for lateral impact; (ii) compulsory and more stringent fatigue assessment; (iii) enhanced structural arrangements for bolts and backing plates; and (iv) informative guidelines regarding keel installation procedures. This is the first public introduction of the current developments inherent to the forthcoming ISO 12215-9:2025, which aims to support the design and manufacturing of safe and reliable keel structures for sailing yachts. Furthermore, it is envisaged this work may contribute to the development of future guidelines and regulations for the structural design of hydrofoils and internal supporting structure
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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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