1,721,041 research outputs found
Timber-concrete composite structures in fire conditions - Finite Element numerical modelling of tensile tests
No full textThe structural behavior of Timber‐Concrete Composite (TCC) slabs, as known, is mainly governed by the load‐bearing capacity of the metal connection between timber and concrete components.
There, a key role is assigned to possible changes in stiffness and strength, especially for TCC systems exposed to fire loading. While simplified formulae are available in the literature for the calculation of strength and stiffness properties of screwed connections, most of the influencing parameters for TCC structural systems should be preferably assessed via time and cost consuming experiments in fire conditions. In this regard, the use of refined Finite Element (FE) models can provide strong support for design developments. Key input features ‐ including
thermal and mechanical material properties, as well as boundary thermo‐mechanical conditions and interactions ‐ should be however properly assessed and calibrated, including connection detailing. In this paper, an advanced FE approach inclusive of cohesive contacts and damage laws is taken into account, from recent literature applications on timber composites in cold conditions, and preliminarily extended to TCC samples in fire. FE results are assessed towards literature test results, with special care for tensile experiments, including a critical discussion of issues and potentials
Finite Element numerical modelling of the fire resistance of log-house walls
No full textThis paper presents a Finite Element (FE) numerical investigation performed on timber log‐house walls with partial thermal insulation, subjected to in‐plane compression and exposed to fire on one side. A key aspect for the design of log‐house walls is represented by geometrical details, like cross‐sectional properties of logs (typically characterised by high depth‐to‐width ratios) and outriggers.
The latter ones act as mechanical restraints for the main walls and hence markedly affect their overall load‐carrying capacity. As a result, careful consideration should be given to the choice of these details, due to the possible occurrence of local structural and/or thermo‐mechanical mechanisms. This is the case of exceptional loading conditions like fire load, as the fire resistance of log‐house systems could be affected by a multitude of variables. The FE investigation herein presented follows and extends an earlier research study on an unprotected log‐house wall, where thermal insulation panels (gypsum fibreboard layers) were added to protect part of the wall. The FE method is assessed and validated against a full‐scale furnace test, including a critical discussion of comparative results
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
Timber concrete composite structures in fire - Final activity report from WG2-TG2
No full textThe structural behaviour of Timber‐Concrete Composite (TCC) slabs, as known, is mainly governed by the shear connection between timber and concrete components. There, a key role is assigned to possible changes in stiffness and strength, especially for TCC systems exposed to fire loading.
In the last years, several studies have been spent for the assessment of the fire performance of TCC systems in fire loading, including experimental, analytical and Finite Element (FE) numerical modelling, see for example [1–5]. In desire to describe the behaviour of TCC elements in fire conditions, effects of temperature on the mechanical properties of timber, concrete, and connection components should be properly taken into account.
In this paper, a final activity report is proposed from the WG2‐TG2 members. First, experimental methods and results are discussed. Then, an insight on the Finite Element numerical modelling of TCC structures in fire is presented
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
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