1,721,223 research outputs found
A state-of-the-art review on fatigue performance of powder bed fusion-built alloy 718
No full textAlloy 718 is a Ni-Fe-based superalloy, which has been successfully adapted to powder bed fusion (PBF) additive manufacturing because of the alloy's adaptability with such emerging technology in achieving enhanced mechanical properties. Despite a promising perspective for PBF-built Alloy 718 in different industries, a few factors, including microstructural non-uniformities, volumetric defects, undesired non-metallic inclusions, anisotropic behavior, residual stress, as well as surface and sub-surface irregularities, lead to premature fatigue life of the parts. However, the PBF technology has been quickly growing, and associate progress has resulted in substantial advances in quality, hence increased fatigue life of the parts. Therefore, a critical assessment of the efficacy of the PBF-built Alloy 718 parts can be highly enlightening. A fundamental understanding of the relationship between feedstock material, manufacturing process, process parameters, microstructure, properties, and fatigue life of PBF-built Alloy 718 is crucial for improving the characteristics of the current materials, designing new alloy systems, and enhancing the capability of the PBF techniques. The present paper aims to comprehensively review the fundamentals and recent advances in the PBF-built Alloy 718 parts with improved fatigue life, the influence of thermal and mechanical post-treatment, mechanisms of fatigue crack initiation and growth, thermo-mechanical fatigue, dwell-time fatigue, as well as fracture behavior in different loading conditions and environments considering anisotropic characteristics of the material. An unbiased review of the literature provides an understanding of the advanced and outstanding achievements in the field that assure further research. An evaluation of the status of the field, the gaps in the theoretical understanding, and the fundamental needs for the sustainable development of PBF-built Alloy 718 with enhanced fatigue life in specific applications are also provided
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
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
Multiscale characterization of Ti-induced grain refinement in additively manufactured austenitic stainless steel
Full text linkIn-situ inoculation of grain-refining elements can effectively mitigate columnar grain growth and alleviate mechanical anisotropy in additively manufactured metals, while enhancing strength via the Hall-Petch effect. However, the refinement mechanism of Ti in austenitic stainless steel remains unclear. This study investigates Mn-assisted Ti inoculation in 316L stainless steel (SS316L), followed by annealing. Despite near-full densification, localized Ti enrichment formed coarse, brittle FeTi and C14 Laves intermetallic clusters, encapsulated by ultrafine ferritic grains within an austenitic matrix. Elevated annealing temperatures dissolved Laves phases and promoted Ti diffusion, resulting in dispersed TiO particles and ferritic domains. Refined Laves phases were redistributed to grain boundaries and triple junctions. Mechanical testing showed improved ductility with increasing annealing temperature: ultimate tensile strength decreased from 650 MPa to 610 MPa, while elongation rose from 13 % to 38 %. Hardness mapping revealed a more uniform distribution, though the maximum hardness dropped from 370 HV to 210 HV. Electrochemical corrosion tests in saline solution indicated that phase transformations induced by Ti-Mn co-inoculation undermined the corrosion resistance of SS316L, rendering it more susceptible to degradation in aggressive environments
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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