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    Data for Characterisation of strain localisation processes during fatigue crack initiation and early crack propagation by SEM-DIC in an advanced disc alloy

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    This dataset is linked to the following paper which is published at Materials Science and Engineering: A Characterisation of strain localisation processes during fatigue crack initiation and early crack propagation by SEM-DIC in an advanced disc alloy R. Jiang*, F. Pierron, S. Octaviani, P.A.S. Reed</span

    Characterisation of strain localisation processes during fatigue crack initiation and early crack propagation by SEM-DIC in an advanced disc alloy

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    Fatigue failure processes in metallic materials are closely related to the evolution of strain localisation under cyclic loading. Characterisation of this strain localisation is important in understanding the mechanisms of fatigue crack initiation and propagation, and provides critical validation data to develop appropriate crystal plasticity models for prediction of these processes. In this study, strain localisation during fatigue crack initiation and early crack propagation in an advanced Ni-based superalloy for turbine disc application has been characterised at the grain level with a sub-micron resolution by digital image correlation on SEM images using secondary γ′ themselves as the speckle pattern. The obtained full-field strains have been analysed in global coordinates associated with the applied loading direction and in terms of the local coordinates associated with individual slip bands. Deformation arising from in-plane and out-of-plane dislocation slip can be identified by a combination of shear strain ɛxy and transverse strain ɛyy in the local slip band coordinates in combination with EBSD analysis. Cracks preferentially initiate from slip/strain bands adjacent and parallel to twin boundaries and then propagate along the slip/strain bands, leading to the onset of significant transverse strain ɛyy in the local band coordinates as a consequence of crack opening. Crack propagation is closely related to strain accumulation at the crack tip which is determined by the grain orientation and grain size. Transverse strain ɛyy in local slip band coordinates together with the inclination angle between dislocation slip direction on an activated {111} plane and the slip trace of this {111} plane at the specimen surface is proposed to be a cracking indicator/fracture criterion

    The behavior of anisotropic fatigue short crack initiation and propagation for a directionally solidified superalloy CM247LC at room temperature

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    The effects of mechanical and microstructural anisotropy on short fatigue crack initiation and propagation behaviors of a directionally solidified superalloy have been studied. An unusual result was found where the fatigue lives of specimens with grains longitudinally aligned along the loading direction fail at lower lifetimes than specimens with transversely loaded grains when the applied stress is close to the yield stress. This is mainly attributed to the lower Young's modulus of the longitudinal specimen, which induces more local plastic strain (at stress concentration features) leading to earlier crack initiation and faster crack propagation under the applied test stress

    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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    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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