1,721,167 research outputs found
Rheology of a lyotropic mesophase through a stress-relaxation experiment
No full textWe report on the first rheological study of the structural relaxations in a nematic liquid crystalline phase. Linear dynamic and transient shear experiments were applied to a polydomain nematic phase of the CTAB/water system: a liquid crystalline mixture composed of 28 wt% CTAB at 35°C. The decay of the shear modulus, G(t), was analyzed using the CONTIN inverse Laplace transform to obtain a distribution of relaxation times which were compared with ones from the usual fitting procedure based on a generalized Maxwell model. The behavior of the nematic lyotropic structure of the CTAB/water system is characterized by the presence of both slow and fast relaxation times. These were interpreted as being due to a progressive loss of the lyotropic domain orientation and to the breaking/reforming process of the cylindrical aggregates, respectively. © 2003 Elsevier Inc. All rights reserved
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
DURABILITY AND CONSERVATION OF TWENTIETH-CENTURY CONCRETE
No full textIn many countries, structures in reinforced concrete “of historical interest” are covered by preservation legislation. In striving to restore them, scholars make use of knowledge accumulated over time. Less well known is the technological research that was part of the production and use of cements and concrete
mixtures for reinforced concretes, whose durability has always been a prime concern. Historic works bear witness to their ability to last over time and to the ways in which structures and materials age and deteriorate, thus providing evidence as to the validity of the expectations of durability which existed when the work was
designed. The systematic collation of data relating to such artefacts and the repairs they have undergone would be of great use (e.g. with regard to the components used in the original work and in the repairs). Furthermore, collaboration with manufacturing companies and research laboratories should allow us to make use of recently developed prepacked mortars and concrete in new repair work, assessing their compatibility with old materials and monitoring their performance over time. The resultant database and experimental results would provide clues useful in moving beyond current rudimentary practices, laying the basis for a shift from “concrete repair to concrete conservation
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
The Durability Of Restoration Of Exposed Concrete. Case Histories Compared
No full textArchitectural works by major architects from the twentieth century have often been subject to restoration campaigns intended to redeem them from decay (sometimes from neglect) in order to present them as “monuments” of the twentieth century. In particular, in architecture in which exposed reinforced concrete plays a key role in architectural, figurative, symbolic and cultural terms, the theme of repairing/replacing the concrete cover is a fundamental issue in the restoration project. Analyzing the methods, materials and techniques of intervention used in several campaigns of restoration of buildings built before World War II (the church of Notre-Dame du Raincy by Gustave and Auguste Perret in France and Rudolf Steiner’s Goetheanum at Dornach near Basel in Switzerland) or after the War (Figini and Pollini’s housing built in Milan and the Olivetti Factory in Crema by Zanuso) provides an opportunity to reflect on the techniques adopted, identifying best practices, but also critical factors and the weaknesses of the different approaches and methods that have affected these buildings from the 1980s to the present
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