1,721,166 research outputs found
Defect crystal chemistry and its applications, par R.J.D. Tilley
No full textTarbes Jérôme. Defect crystal chemistry and its applications, par R.J.D. Tilley. In: Bulletin de Minéralogie, volume 110, 4, 1987. p. 466
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
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
29. The Oxyrhynchus Papyri, volume LIV, edited with translations and notes by M. A. Cole, H. Maehler, P. L. Parsons, with contributions by J..M. Bremer, R.J.D. Carden
No full textBlanchard Alain. 29. The Oxyrhynchus Papyri, volume LIV, edited with translations and notes by M. A. Cole, H. Maehler, P. L. Parsons, with contributions by J..M. Bremer, R.J.D. Carden. In: Revue des Études Grecques, tome 103, fascicule 490-491, Janvier-juin 1990. pp. 293-295
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
North Atlantic Organized Track System Allocation Optimization
No full textTransatlantic flight operations are, due to the absence of radar-based surveillance, the influence of the polar jet stream and the highly directional traffic peaks, significantly different compared to continental flight operations. To safely accommodate all transatlantic traffic in the North Atlantic oceanic airspace the Organized Track System (OTS) has been established, existing of a number of pre-determined flight routes. Currently, about half of all transatlantic traffic uses the OTS which is created twice a day, once to accommodate the westbound traffic and once to accommodate the eastbound traffic flow. All aircraft requesting to use the OTS send an oceanic clearance request to the oceanic planning controller, containing the estimated time of arrival at the track entry boundary, the preferred OTS track, flight level and Mach number. The aircraft are cleared onto the OTS using a first-come, first-served (FCFS) approach, taking the separation requirements with already cleared aircraft into account. If an oceanic clearance request cannot be granted due to a potential loss of separation, the requesting aircraft will receive an alternative clearance. The research objectives of this thesis assignment are to: “Reduce the total direct operating cost of transatlantic air traffic by optimizing the OTS track allocation procedure using a real-time meta-heuristic scheduling algorithm” “Create a model capable of optimizing the OTS track allocation procedure for different cost-index values” This research aims at improving the current OTS track allocation procedure by changing the first-come, first-served approach, currently used, to a scheduling concept in which the total direct operating cost (DOC) is minimized for a large number of aircraft in a single optimization window. The use of a meta-heuristic optimization algorithm is proposed in this thesis project and the potential of using stochastic optimization for large scheduling problems is researched. The direct operating cost penalties for the possible alternative clearances is determined using fuel consumption models in combination with time cost models. The created population algorithm is tested for multiple cost-index values, using real life problems, and the results are compared to the existing OTS track allocation procedure. The generated results show a potential direct operating cost reduction as well as the possibility to use the created track allocation algorithm as a real-time decision support tool for the oceanic planning controller.Air Tranport and OperationsControl and SimulationAerospace Engineerin
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