1,720,973 research outputs found
Extension of dynamics of polymeric liquids methodology to new areas
No full textWe investigate analogies between the methodology typical of the dynamics of polymeric liquids with those used in a seemingly entirely unrelated area, viz., granular flow theory and we show that the essential conceptual content of the approach is in fact the same in both areas. We also discuss the theory of compressible flow of granular materials, something for which an analogy with the dynamics of polymeric liquids is not available, but an area where similarities and crucial differences with classical compressible flow theory are of interest. (C) 1998 Elsevier Science B.V. All rights reserved
The Rayleigh approach to the rheology of compressible granular flow
No full textWe develop a Rayleigh-type approach to the analysis of compressible granular flow. In this approach, a (possibly negative) influx of energy from the walls is taken into account. This is greatly advantageous in granular flow rheology, since such influx of energy arises spontaneously as soon as the balance between the energy influx (due to whatever mechanism keeps the unperturbed system in a thermalized state) and the dissipation rate is violated. We show that standing waves, although waves of a rather peculiar type, may well exist, and that such waves have thicknesses of several hundreds particle diameters. We also give an analysis of the stability of compressible granular flow, which exhibits some peculiar characteristics. (C) 1997 The Society of Rheology
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
Statistical thermodynamic theory of the cell cycle:The state variables of a collection of cells
No full textWe have recently presented a series of papers [A. Kummer, R. Ocone, Physica A 321 (2003) 587; A. Kummer, R. Ocone, Chem. Phys. Lett. 377 (2003) 627; A. Kummer, R. Ocone, Chem. Phys. Lett. 388 (2004) 322] where a thermodynamic theory of the cell cycle has been introduced and the analogy with the kinetic theory has been discussed. Based on such conceptual framework, here we clarify the concept of metabolic temperature [A. Kummer, R. Ocone, Physica A 321 (2003) 587], we show how the latter is extended from a single cell to a collection of cells and we discuss the significance of thermodynamic-like variables such as pressure. In deriving the explicit form (the constitutive relation) for the metabolic pressure, we conclude that any other state variable for the cellular 'ensemble' can be derived from the theory. © 2004 Elsevier B.V. All rights reserved.</p
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
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