1,723,608 research outputs found
Effect of metal temperature on the short contact time adhesion of molten poly(ethylene terephthalate)
Full text linkThis study focused on the effect of metal temperature on the short contact time (few milliseconds) adhesiveness
of a molten poly(ethylene terephthalate) (PET) cylinder. Although such a short contact time is typical for PET
cylinder handling during preform compression molding (an innovative technique which has many advantages
over injection molding, such as higher sustainability, owing to the lower energy and raw material consumption),
this type of PET–metal contact has not been examined in the literature. Therefore, a new experiment was
designed to test two different metals: stainless steel (AISI 316) and an aluminum alloy (EN AW-6082-T6). Both
metal surfaces were finished to achieve nearly identical roughness and morphology as measured by profilometers, while their contact angles were determined according to previous studies. Afterwards, a series of tests
including more than 300 single contacts were performed to monitor several parameters affecting PET adhesiveness. The obtained results revealed that the two tested materials exhibited different properties and suggested
a probable short contact time adhesion mechanism. This study may be used as reference in the selection of
appropriate materials and temperature for molten PET cylinder handling tools. Moreover, since the described
phenomenon was previously unknown to the scientific community, this research could be useful in many other
research and industrial fields.This study focused on the effect of metal temperature on the short contact time (few milliseconds) adhesiveness of a molten poly(ethylene terephthalate) (PET) cylinder. Although such a short contact time is typical for PET cylinder handling during preform compression molding (an innovative technique which has many advantages over injection molding, such as higher sustainability, owing to the lower energy and raw material consumption), this type of PET–metal contact has not been examined in the literature. Therefore, a new experiment was designed to test two different metals: stainless steel (AISI 316) and an aluminum alloy (EN AW-6082-T6). Both metal surfaces were finished to achieve nearly identical roughness and morphology as measured by profilometers, while their contact angles were determined according to previous studies. Afterwards, a series of tests including more than 300 single contacts were performed to monitor several parameters affecting PET adhesiveness. The obtained results revealed that the two tested materials exhibited different properties and suggested a probable short contact time adhesion mechanism. This study may be used as reference in the selection of appropriate materials and temperature for molten PET cylinder handling tools. Moreover, since the described phenomenon was previously unknown to the scientific community, this research could be useful in many other research and industrial fields
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
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
Services trade policy and manufacturing productivity: The role of institutions
No full textWe study the effect of services trade restrictions on manufacturing productivity for a broad cross-section of countries at different stages of economic development. Decreasing services trade restrictiveness has a positive impact on the manufacturing sectors that use services as intermediate inputs in production. We identify a critical role of institutions in importing countries in shaping this effect. Countries with high institutional quality benefit the most from lower services trade restrictions in terms of increased productivity in downstream industries. We show that the conditioning effect of institutions operates through services trade that involves foreign establishment (investment), as opposed to cross-border arms-length trade in services
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
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