1,721,012 research outputs found
Étude sur les Travaux du professeur G. Boccardi concernant la variation des latitudes
No full textB. B. Étude sur les Travaux du professeur G. Boccardi concernant la variation des latitudes. In: Bulletin astronomique, tome 33, 1916. pp. 303-313
G. Boccardi. — Elementi di Astronomia. Parte II : Teoria della Luna elementarmente esposta. Torino, 1912
No full textA. H. G. Boccardi. — Elementi di Astronomia. Parte II : Teoria della Luna elementarmente esposta. Torino, 1912. In: Bulletin astronomique, tome 30, 1913. p. 173
G. Boccardi — Relazione sulla altività scientifica del R. Osservatorio di Torino durante l’anno 1906-1907. Turin, 1907 ; in-8°, 6 pages
No full textR. G. Boccardi — Relazione sulla altività scientifica del R. Osservatorio di Torino durante l’anno 1906-1907. Turin, 1907 ; in-8°, 6 pages. In: Bulletin astronomique, tome 25, 1908. p. 205
WATER TWO-PHASE FLOW THROUGH A CONVERGENT-DIVERGENT NOZZLE WITH VARIABLE BACKPRESSURE: CHECK OF CALCULATION METHOD TO ESTIMATE MASS FLOWRATE AND CRITICAL FLOW CONDITIONS
No full textAbstract - A careful design of the pressure safety valves (PSV) is an essential requisite for safeguarding of industrial plants; if two-phase flow is possible, it is very important for their correct design to predict the onset of the critical flow. This phenomenon occurs when the fluid velocity becomes equal or higher than the sound velocity in the fluid. Some other interesting aspects for the PSV design are the calculation of the subcritical two-phase flowrate and the back-pressure effect on the valve discharge performance. This paper shows the results of an experimental research carried out with steam-water two-phase through a convergent-divergent nozzle. The effect of some test parameters, such as inlet pressure and quality, mass flowrate, back-pressure, on the flow behaviour are evaluated. The experimental data are also compared with the results of a calculation method based on the homogeneous equilibrium model. The results show quite a good reliability of the model, with some uncertainties related to the test procedures (the mass flow rate is imposed); indeed, this condition makes difficult the checking of the critical flow arising, in spite of the help of the experimental data on the test section pressure profile
Comparative analysis of calculation methods of pressure drops for two-phase flow through pipelines
No full textDespite the importance of an adequate and correct sizing of emergency relief systems, a high level of uncertainty is still present when two-phase liquid-vapor flow can establish. In such a case, no single correlation is presently generally applicable to calculate the pressure drop through a relief pipeline in a wide range of relief conditions. In the present paper a large number of new experimental data have been produced and compared with two of the most widely known and adopted calculation methods: the Friedel model and the classical Lockhart-Martinelli model. They belong to either of the two main groups of prediction models, the homogeneous and non-homogeneous models. The results provide useful insights in their accuracy and range of applicability, and are expected to be of help in the correct sizing of these fundamental safety system
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
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