1,720,957 research outputs found
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
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
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
Development of a test method to determine the low temperature performance of Bitumen
Get PDFDas Ziel dieser Arbeit war es, eine Prüfmethode zu entwickeln, die eine Charakterisierung der Bindemitteleigenschaften im Tieftemperaturbereich prozesssicher und mit moderatem Prüfaufwand ermöglicht. Die verwendeten Prüfgeräte sollten hierbei modern, aber an hinreichend vielen Prüfstellen vorhandenen sein.
Aufbauend auf einer internationale Literarturrecherche wurden folgende vier DSR-Prüfverfahren ausgewählt, die diesen Rahmenbedingungen entsprachen:
• Scher-Relaxationsversuch (SRV)
• Kälteprüfung mit der 4 mm Platte-Platte-Geometrie (PP04)
• Zug-Relaxationsversuch (ZRV)
• Kälteprüfung an schlanken, zylindrischen Proben – dynamisch-mechanische Thermoanalyse (DMTA)
Zur Auswahl des Prüfverfahrens, wurde ein dreistufiges Untersuchungsprogramm entworfen. Im ersten Schritt wurden zehn Bindemittel, mit allen vier Verfahren untersucht. Auf Grundlage der Ergebnisse dieses Untersuchungspaketes, wurden der SRV und die Untersuchung mittels PP04 für die Hauptuntersuchungen ausgewählt.
In diesem Schritt wurden 40 weitere Bindemittel mit den beiden Prüfverfahren untersucht. Mit diesen Daten konnten erste Auswertungsmethoden entwickelt und überprüft werden.
Abschließend wurden die Ergebnisse der beiden Methoden in der Validierung unter Verwendung des BBR und des Zug-Retardationsversuches überprüft. Im Laufe dieses Projektes wurden insgesamt 72 Bindemittel mit dem SRV und der PP04 untersucht. Die Auswertung des SRVs erfolgte mit der Relaxationsviskosität λRel. Zur Bewertung des Kälteverhaltens der Bindemittel mit der PP04, wurde die Summe der Phasenwinkel von -20, -10 und 0 °C verwendet. Die Korrelationen zu den anerkannten Verfahren lagen auf sehr hohem Niveau. Neben der Vergleichbarkeit mit bekannten Prüfmethoden, wurde im Zuge der Validierung auch der Einfluss des Prüfenden analysiert. Weiterhin wurden kritische Werte der beiden Verfahren, zur Beurteilung des Kälteverhaltens von Bitumen bestimmt und der SRV als Prüfmethode zur Beurteilung des Kälteverhaltens von Bitumen vorgeschlagen.The aim of this project was to develop a test method for characterising the low temperature performance of Bitumen. The used test device should be modern and also present in many testing laboratories.
Based on an international research the following four DSR-Methods were chosen:
• The Shear-Relaxation-Test (SRV) - A Creep stress test at -10 °C that uses the 8 mm diameter parallel plates (rotation).
• The Tensile-Relaxation-Test (ZRV) - A Creep stress test at -10 °C that uses the 8 mm diameter parallel plates (normal direction).
• The 4-mm DSR – An oscillation test, performing a frequency sweep from 0.01 Hz to 10 Hz at various temperatures from -20 °C to 30 °C, using the 4 mm diameter parallel plates.
• The Dynamic Mechanical Thermal Analysis (DMTA) – An oscillation test using slender cylindrical samples (h = 12 mm; d = 8 mm).
To determine the most suitable of these four methods, a three-step experimental work is engineered. In the first step all four methods were used to analyze ten different types of bitumen. After this, the SRV and the PP04 were chosen to characterize additional 40 types. The last step was the validation of the results, using the Bending-Beam-Rheometer (BBR) and the tensile-retardation-test by Schellenberg. Overall 72 bitumen were analysed with the SRV and the PP04. To assess the SRV the relaxation-viscosity λRel was used. For the Assessment of the method using the PP04, the sum of the phase angle measured at a frequency of 0.01 Hz within the temperature range from -20 to 0 °C was used. The correlations between the two renowned methods and the two new methods were very good. Also the effect of the tester was analised during the validation.
Finally critical values for the results were determined and the SRV was chosen as most suitable method to characterise the low temperature performance of bitumen
Rheologische Parameter zur Beurteilung des Tieftemperaturverhaltens von Bitumen
No full textIm Zuge dieser Arbeit wurden 171 Bindemittel unterschiedlichster Art, Modifikation und Alterungsgrad mit ausgewählten DSR-Methoden untersucht.
Für jede DSR-Methode wurden verschiedene Bewertungsansätze statistisch ausgewertet und analysiert. Aufbauend auf den ermittelten Ergebnissen, kann als Schnellprüfverfahren der Scher-Relaxationsversuch (SRV) empfohlen werden. Für den SRV wurde als Bewertungsparameter das Integral der Scherspannung während der Relaxationsdauer empfohlen. Alternativ ist auch die Prüfung mit der PP04-Messgeometrie geeignet. Diese ist zeitaufwendiger, ermöglicht allerdings eine detailliertere wissenschaftliche Charakterisierung der Tieftemperatureigenschaften.
Aufbauend auf Korrelationen mit anderen Prüfverfahren (BBR) sowie den Ergebnissen der Bindemittel aus bekannten Schadensfällen konnten für beide Methoden Grenzwerte vorgeschlagen werden, mit denen die mögliche Bildung von Rissen aufgrund von mangelhaftem Tieftemperaturverhalten abgegrenzt werden kann
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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