1,721,051 research outputs found

    Prediction of mechanical properties in spheroidal cast iron by neural networks

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    An artificial neural network-based system is proposed to predict mechanical properties in spheroidal cast iron. Several castings of various compositions and modules were produced, starting from different inoculation temperatures and with different cooling times. The mechanical properties were then evaluated by means of tension tests. Process parameters and mechanical properties were then used as a training set for an artificial neural network. Different neural structures were tested, from the simple perceptron up to the multilayer perceptron with two hidden layers, and evaluated by means of a validation set. The results have shown excellent predictive capability of the neural networks as regards maximum tensile strength, when the variation range of strength does not exceed 100 MPa

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    Slow slip events and flank instability at Mt. Etna volcano (Italy)

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    We analyzed a set of 11 slow slip events occurred during the 2006–2016 period and affecting the GNSS (Global Navigation Satellite System) stations of the unstable flank of Mt. Etna volcano. Observed surface deformation for most of the detected slow slip events, concentrates on the south-eastern edge of the unstable flank while the slow slip events involving the north-eastern edge are less frequent. Such a pattern highlights the existence of two distinct families of events, involving two contiguous sectors of the unstable flank, which occasionally slip together in large slow slip events. The modelled slips also highlight that both contiguous sectors extend ~10–12 km offshore, on areas where active tectonic lineaments such as the ESE (northward of Catania Canyon) and the N102° (along the southern slope of the Riposto Ridge) ones have been recently discovered. Equivalent seismic moments of slow slip events occurred in the last ten years (corresponding to magnitudes in the range 5.4–5.9) are larger than those associated to seismic events observed in the last 200 years, suggesting that most of the deformation affecting the eastern flank occurs aseismically

    Mid-infrared second harmonic generation in p-type Ge/SiGe quantum wells: Toward waveguide integration

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    In this work we investigate a structure based on p-doped Ge/SiGe asymmetric-coupled quantum wells (ACQW) that enables the second harmonic generation in SiGe waveguide by double-resonant intersubband transitions (ISBTs). These transitions lead to χ(2) coefficients in the range 104-105 pm/V, significantly higher compared to the one of conventional nonlinear materials. We developed a model for the integration of Quantum Wells (QWs) into the active region of the waveguide through an adiabatic taper. Furthermore, we modelled the second harmonic (SH) conversion efficiency as a function of the propagation length, under both non-phase matching and phase-matching conditions. Our work demonstrates that the SiGe ACQWs can be used in spectral ranges not covered by the majority of conventional non-linear crystals, while allowing for the ready-integration with the CMOS technologies

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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