1,721,022 research outputs found
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
Valutazione del comportamento sismico di telai in c.a. con muratura di tamponamento mediante modelli di danno
No full textIl presente articolo propone l’impiego di un modello numerico per l’analisi della risposta non-lineare di strutture a telaio in c.a. con tamponamenti in muratura che sia sufficientemente affidabile ed applicabile allo studio di strutture in scala reale. Gli elementi in c.a. sono discretizzati mediante elementi monodimensionali a plasticità diffusa. I pannelli di muratura sono simulati con elementi finiti shell a 4 nodi con sollecitazione puramente membranale. Per la muratura si è adottato un legame costitutivo basato sulla meccanica del danno sviluppato nel caso isotropo ed opportunamente tarato. Si riportano analisi e confronti con le prove sperimentali di semplici portali con tamponamento in presenza o meno di aperture. Validata quindi la procedura proposta, si analizza il comportamento di un telaio multipiano con diverse condizioni di tamponamento
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
Studio della risposta sismica di sistemi terreno-struttura con il metodo degli elementi finiti
No full text
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
A coupled damage model for the structural analysis of r.c. structures exposed to freeze–thaw cycles
No full textDue to the extensive use of reinforced concrete as building materials in the last century, even in severe and aggressive environment, the demand for designing durable structure has increased together with the need for developing reliable and appropriate models which allow the prediction of concrete behaviour on time. One of the most severe types of deterioration in r.c. structures is associated to the volume expansion of concrete caused by frost attack. Actually in cold environments, freezing and thawing can be detrimental for a brittle material such as concrete, especially related to its porosity characteristics.
The causes and mechanisms of frost damaging process have been dealt with by several research papers, but very little attention has been given to the effect of frost attack on the material characteristics and on the bond properties of concrete, see e.g. [1] where it has been shown that the relations between compressive and tensile strength for undamaged concrete cannot be used directly for frost-damaged concrete.
In this paper the environmental-mechanical coupled damage model, based on the works of Saetta et al [2] – [3] and Tesser et al. [4] was developed accounting for the deterioration of concrete during the freeze-thawing (F/T) process. A 4-node finite element based on Reissner-Mindlin thick plate formulation with Mixed Interpolation of Tensorial Components is used. Stress resultants are evaluated via numerical integration of the concrete plastic damage model over the thickness.
Moreover an enhanced formulation [5] of the environmental damage is presented, which takes into account the effect of the number of F/T cycles on the value of concrete strength and ductility. In particular both uniaxial and biaxial experimental tests of concrete subjected to frost damage were considered and an optimization technique was adopted to calibrate the coupled damage model. Test results showed a significant influence of freeze–thaw cycles on the compressive strength and on biaxial behaviour. Finally the paper presents a case study able to evaluate the model capabilities
Il metodo degli elementi finiti in spazio ed in tempo per la soluzione delle equazioni dell'equilibrio dinamico
No full text- …
