1,723,443 research outputs found
Photometry of the Galactic Cluster NGC 6649
Get PDFIchtisar. Dengan mengggunakan teknik fotoelektrik dan fotografik diberikanlah magnitudo dan warna daripada 80 bintang dalam gugus galaktik NGC 6649, dalam UBV Johnson. Dengan menggunakan reflektor 60 intji di Observatorium Boyden telah didapatkan observasi fotoelektrik dalam 3 warna. Untuk fotometri forografik telah diambil katja2 potret dalam 2 warna dengan menggunakan teleskop Schmidt 20-28 intji di Lembang. Modulus djarak visuil semu daripada NGC 6649 adalah 14,2 mag, ekses warnanja ialah 1,2 mag, dan modulus sesungguhnja ialah 10,6 mag., sesuai dengan djarak 1300 parsek. Observasi fotoelektrik membuktikan bahwa salah sebuah bintang dalam NGC 6649 mungkin adalah sebuah bintang berubah Cepheid Abstract. By using photoelectric and photographic techniques magnitudes and colours in the Jhonson UBC system are given for eighty stars in the galactic cluster NGC 6649. Photoelectric three-colour observations were made with the 60 inch reflector at the Boyden Observatory. Photographic plates taken in two colours with the 20-28 inch Scmidht type telescope at Lembang were used for photographic photometry. The apparent visual distance modulus of NGC 6649 is 14.2 mag., the colour excess is1.2 mag. and the true modulus, corresponding to a distance of 1300 parsecs. The photoelectric observation show that one of the stars in the cluster of NGC 6649 is a possible Cepheid variable.
[Lehigh & New England, Engine Drawing Card, Sketch No. 6649]
No full textThis engine drawing card was created for Lehigh & New England Railroad, Class 20 48/76 1/4 EE. Section J-20 1/4 EE. Sketch 6649. Copy Spec. C-5233
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
Sale 6649
No full textItems 3-7 of this beautiful catalogue are books of Aesopic fables with asking prices that start with 300,000 for del Tuppo's 1485 version (#3, also illustrated in the frontispiece). Each edition receives an extensive historical comment, an illustration, and a half-page of technical data. #4 is from Boninus de Boninis, third edition, 1487, with Accio Zucco as translator and editor; it is also pictured on the book's cover. #5 and #6 are both Venetian, both based at least in part on the original Venetian woodcuts of Bernardino Benalio (1487). #7 is an 1800 Bodoni that has an asking price of only 2000-3000. I ordered the book on a good tip from June Clinton. It is the 2000th book in my collection.Sotheby'
RXTE confirmation of the intermediate polar status of IGR J15094–6649
Get PDFAims. We aim to establish the X-ray properties of the intermediate polar candidate IGR J15094–6649 and therefore confirm its inclusion into the class.
Methods. 42 856 s of X-ray data from RXTE was analysed. Frequency analysis was used to constrain temporal variations and spectral analysis used to characterise the emission and absorption properties.
Results. A spin period of 809.7 ± 0.6 s is present, revealed as a complex pulse profile whose modulation depth decreases with increasing X-ray energy. The spectrum is well fitted by either a 17 ± 4 keV Bremsstrahlung or ? = 1.8 ± 0.1 power law, with an iron emission line feature and significant absorption in each case.
Conclusions. IGR J15094–6649 is confirmed to be an intermediate polar.
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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
Three open clusters containing Cepheids: NGC 6649, NGC 6664, and Berkeley 55
Get PDFClassical Cepheids in open clusters play an important role in benchmarking stellar evolution models, in addition to anchoring the cosmic distance scale and invariably securing the Hubble constant. Three pertinent clusters hosting classical Cepheids and red (super)giants are: NGC 6649, NGC 6664, and Berkeley 55. These clusters form the basis of analysis to assess newly acquired spectra (≈50), archival photometry, and Gaia DR2 data. Importantly, for the first time chemical abundances were determined for the evolved members of NGC 6649 and NGC 6664. We find that they are slightly metal-poor relative to the mean Galactic gradient. Also, an overabundance of Ba is observed. These two clusters likely belong to the thin disc and the latter finding supports the “s-enhanced” scenario of D’Orazi et al. (2009). NGC 6664 and Berkeley 55 exhibit radial velocities consistent with Galactic rotation, while NGC 6649 displays a peculiar velocity. The resulting age estimates for the clusters (≈70 Ma) imply masses of ≈6 M⊙ for the (super)giant demographic. Lastly, the observed yellow-to-red (super)giant ratio is lower than expected and the overall differences that are relative to the models reflect the outstanding theoretical uncertainties
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