1,721,215 research outputs found
Cell Method Analysis of Crack Propagation in Tensioned Concrete Plates
No full textIn this study, the problem of finding the complete trajectory of propagation and the limiting load in plates with internal straight cracks is extended to the non-linear field. In particular, results concerning concrete plates in bi-axial tensile loading are shown. The concrete constitutive law adopted for this purpose is monotonic non-decreasing, as following according to previous studies of the author on monotonic mono-axial loading. The analysis is performed in a discrete form, by means of the Cell Method (CM). The aim of this study is both to test the new concrete constitutive law in biaxial tensile load and to verify the applicability of the CM in crack propagation problems for bodies of non-linear material. The discrete analysis allows us to identify the crack initiation without using the stress intensity factors
A Higher Order Solution of the Elastic Problem for a Homogeneous, Linear-Elastic and Isotropic Half-Space Subjected to a Point-Load Perpendicular to the Surface
No full textA recent experimental programme with the aim of acquiring the strains induced by aircraft traffic in concrete pavements has provided the opportunity of reviewing the classical solution of Boussinesq’s problem for a homogeneous linear-elastic and isotropic half-space subjected to a point-load. In this document, we have proposed a second order solution to Boussinesq’s problem, which allows us to account for the new experimental evidence
Navigare in Arno. Acque, uomini e marmi tra Firenze e il mare in Età Moderna
No full textQuesto volume nasce da studi e ricerche iniziate dagli autori nel 1997, a partire dalla mostra “Empoli. Città e territorio. Vedute e mappe dal ’500 al ’900” e proseguite senza soluzione di continuità nel decennio successivo, nel quadro di una articolata collaborazione con il Sistema museale Le Terre del Rinascimento e con i Comuni del Montalbano, propaggine meridionale degli Appennini compresa tra Firenze, Pistoia e l’Arno. Tale percorso condiviso si è concretizzato in progetti di valorizzazione, analisi storica e censimento che hanno accompagnato piani strutturali, interventi di restauro, iniziative di didattica dei beni culturali per le scuole e gli adulti. In questo contesto gli autori hanno compiuto anche approfondimenti di temi leonardiani nell’ambito di accordi fra la Biblioteca Leonardiana e l’Università di Firenze.
L’imponente ricerca si è mossa sul binario concettuale Montalbano - Arno, fra tardo Medioevo ed Età Moderna, inteso come una vera e propria matrice paesaggistica, culturale, sociale ed economica, che ha informato la storia di un brano della Toscana nord-occidentale compreso tra le province di Firenze, Prato, Pistoia e proiettato attraverso il fiume verso la costa tirrenica e l’entroterra pisano e lucchese; si tratta di una storia che ha trovato numerosi punti di contatto con i grandi eventi politici, sociali e culturali dello scenario nazionale ed internazionale coinvolgendo personalità di primo piano quali Lorenzo il Magnifico, Niccolò Machiavelli, Cosimo I de’Medici, i papi Giulio II e Leone X, e artisti come Filippo Brunelleschi, Leonardo da Vinci, Michelangelo Buonarroti.
Il volume rappresenta una sintesi dello studio analitico compiuto dagli autori in oltre dodici anni di lavoro e raccoglie brevi saggi che sviluppano temi complessi, secondo una impostazione che ha privilegiato l'obiettivo divulgativo per rispondere al desiderio di conoscenza del turismo culturale ancor prima che del pubblico degli studiosi, a cui si offre in particolare un’articolata e aggiornata bibliografia ed un’ampia raccolta iconografica, frutto di una campagna fotografica appositamente realizzata con materiale in gran parte inedito.
Titoli dei capitoli:
- Il corso del fiume e le opere idrauliche;
- La navigazione dell'Arno tra Firenze e Pisa;
- Vie d'acqua, vie di terra;
- L'acqua come forza motrice: i mulini e gli opifici;
- L'Arno come promenade tra ville e bandite di caccia;
- I marmi sul fiume dalle cave ai cantieri di architettura
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
A Cell Method stress analysis in floor tiles subjected to temperature variation
Full text linkThe Cell Method is applied in order to model the debonding mechanism in ceramic floor tiles subjected to positive thermal variation. The causes of thermal debonding, very usual in radiant heat floors, have not been fully clarified at the moment. There exist only a few simplified analytical approaches that assimilate this problem to an eccentric tile compression, but these approaches introduce axial forces that, in reality, do not exist. In our work we have abandoned the simplified closed form solution in favor of a numerical solution, which models the interaction between tiles and sub-base more realistically, when the positive thermal variation increases the volume of the sub-base. The thermal problem has been approached as a contact problem in a composite structure. In particular, the kinematic and equilibrium conditions have been imposed at the interface between lower part, which is the sub-base, and the upper part, which is composed by the adhesive, the tiles, and the grouting between the tiles. The failure condition has been studied in the Mohr-Coulomb plane by using the Leon criterion, a unifying criterion that combines the shear stress with traction and compression. Therefore, we employed a unique failure criterion both for the nodes at the interface between sub-base and adhesive (which undergo a shear/tensile failure or a shear failure) and the nodes at the interface between tiles and grouting (which undergo a tensile failure). This allowed us to model the tile debonding both in the horizontal and in the vertical interfaces, while previous FEM codes treated the tile debonding only on the horizontal interfaces. The numerical analyses were performed in parametric modality, by varying the geometric and mechanical characteristics of the model. Particular attention was devoted to the modeling of thin tiles, a new type of ceramic tiles, for which there are no yet consensus standards
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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