1,720,983 research outputs found
Calibration of the viscoelastic behavior of polypropylene fiber reinforced concrete with the extended Lattice Discrete Particle Model approach
No full textFiber reinforced concrete (FRC) is a composite material whose adoption is becoming widespread. The ability of exhibiting remarkable residual capacity after cracking of the cementitious matrix represents its characteristic feature.
At present, studies dealing with the mechanical characterization of this material are mainly focused on the analysis of the mechanical behavior under short-term conditions. On the other hand, a comprehensive identification of FRC performance requires also the investigation of the rheological properties and the long-term behavior. To this purpose, some researches are making first steps towards the standardization of the creep testing methodologies for FRCs, together with the study of the relevant aspects influencing their time-dependent behavior.
On the other side, the numerical simulation of the FRCs behavior is another challenging topic, due to the composite nature of the material. In particular, the reliability of the model is often driven by the method of introducing the concrete heterogeneity and the fiber distribution. Among the others, the extended lattice discrete particle model (LDPM-F) approach is able to describe the instantaneous composite material behavior through the inclusion of fibers and the simulation of the crack-bridging effect responsible for the FRCs residual strength. At the same time, conventional LPDM model can be coupled with the HTC model and the microprestress solidification theory to fully reproduces the concrete viscoelasticity and aging properties.
In the present paper, a new version of LPDM model has been proposed, where both a concrete viscosity and a fiber viscosity are utilize to describe the long-term behavior of FRC. In the case of plastic fibers (MS), the contribution of fibers to the creep deformation is remarkable. The numerical predictive model has been calibrated with respect to experimental results obtained from instantaneous and creep tests on macro-synthetic fiber reinforced concrete (MSFRC) with polypropylene fibers. In particular, fiber viscoelasticity has been calibrated against tensile creep tests for a single fiber. The validated model has been then used to predict the long-term elongation of pre-cracked notched MSFRC cylinders under the uniaxial tensile stress. Results show that the presented numerical scheme is able to capture this complex behavior
Alexandr Blok – umění a humanizmus
Full text linkThe aim of the study is to interpret the work of art and the essayistic work of the “younger generation symbolist” Alexander Blok. The attention is paid to Blok’s aesthetic-philosophical conception of art. In his works, the author also tries to identify the principles that formed human civilization and culture as the harmonic whole and the principles which can lead to a disruption of that unity
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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