1,723,135 research outputs found
SS Lac in Open Cluster NGC 7209
No full textWe present IUE observations in far ultraviolet region for SS Lac in open cluster NGC 7209. The IUE short wavelength spectrum and long wavelength spectrum were merged to produce an energy distribution curve between 1200A and 3200A. The curve has been unreddened to take out reddening effect. Then the surface temperature, gravity and abundance of SS Lac were determined based on the Kurucz model atmosphere. The photographic light curve produced before cessation of eclipse were analyzed for photometric solutions. We confirmed SS Lac is a member of open cluster NGC 7209 based on its possible distance. The main reason for the cessation of eclipse is the change of the system's orbital inclination rather than collisional merger of two stars
Carpothèque et antracothèque de l'UMR 7209 AASPE
No full textResponsables scientifiques : Charlène Bouchaud (CR, CNRS), Aurélie Salavert (MC, MNHN) ; Responsable technique : Michel Lemoine (IE CNRS) La collection de comparaison archéobotanique de l'UMR 7209-AASPE (MNHN-CNRS) comprend une carpothèque et une antracothèque. La carpothèque est constituée d’environ 9300 spécimens, représentant 4600 taxons. Elle est subdivisée en 6 collections : Europe, Orient et Afrique aride/semi-aride, Asie du sud-est (dont Inde et Océanie), Maghreb (Maroc), Caraïbes, A..
2789-7209-1-PB.pdf
No full textTransformer’s efficiency is essential and significantly affects the transformer’s performance in delivering power. The efficiency is affected by copper losses, of which value is not constant. To improve a state-owned electricity company in Indonesia (PLN) in increasing the optimization of transformer loading, a more accurate calculation of transformer copper losses is needed. In this study, a new
method was proposed to assess the value of copper losses using a fuzzy system, namely the first-order Takagi-Sugeno-Kang (TSK) method combined with Singular Value Decomposition (SVD). The fuzzy system was built based on training data. Upon this data, clustering was carried out with fuzzy c-mean (FCM). The results of the FCM were cluster centers, which were then used to construct membership functions and fuzzy rules. The parameters on the consequent of each first-order TSK fuzzy rule were determined using SVD. The last step was defuzzification to obtain the value of the transformer copper losses.
The defuzzification method used was the weight average. The fuzzy system that had been built was tested on all data to determine and obtain the accuracy of the
copper losses values. The results of this study indicated that the determination of transformer copper losses with a fuzzy system for training and testing data have
accuracies of 99.3354% and 99.6490%, respectively. Furthermore, the first-order TSK method gives better results than that of the zero-order TSK and Mamdani
methods. </p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
No full textWe 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
No full textWe 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
CCD UBV photometric study of five open clusters-Dolidze 36, NGC 6728, NGC 6800, NGC 7209, and Platais 1
No full textIn this study, we present CCD UBV photometry of poorly studied open star clusters, Dolidze 36, NGC 6728, NGC 6800, NGC 7209, and Platais 1, located in the first and second Galactic quadrants. Observations were obtained with T100, the 1-m telescope of the TBA degrees TAK National Observatory. Using photometric data, we determined several astrophysical parameters such as reddening, distance, metallicity and ages and from them, initial mass functions, integrated magnitudes and colours. We took into account the proper motions of the observed stars to calculate the membership probabilities. The colour excesses and metallicities were determined independently using two-colour diagrams. After obtaining the colour excesses of the clusters Dolidze 36, NGC 6728, NGC 6800, NGC 7209, and Platais 1 as , , , , and mag, respectively, the metallicities are found to be , , , , and dex, respectively. Furthermore, using these parameters, distance moduli and age of the clusters were also calculated from colour-magnitude diagrams simultaneously using PARSEC theoretical models. The distances to the clusters Dolidze 36, NGC 6728, NGC 6800, NGC 7209, and Platais 1 are , , , , and pc, respectively, while corresponding ages are , , , , and Myr, respectively. Our results are compatible with those found in previous studies. The mass function of each cluster is derived. The slopes of the mass functions of the open clusters range from 1.31 to 1.58, which are in agreement with Salpeter's initial mass function. We also found integrated absolute magnitudes varying from -4.08 to -3.40 for the clusters
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