1,720,960 research outputs found
Comparison of different finite element model updates based on experimental onsite testing: the case study of San Giovanni in Macerata
Get PDFUnderstanding the behavior of historic structures that have undergone structural changes, restorations, and damage over time is still a significant challenge for structural engineers, particularly in those countries subject to high seismic risk, such as Italy. The study of built heritage for its prevention and conservation is an active research topic, due to the numerous uncertainties present in historic structures. Finite element modelling has become the most common and accessible method to study the behavior of complex masonry structures, however, the gap between numerical and experimental analysis may lead to erroneous results. Model updating techniques can reduce the discrepancy between the behavior of the numerical models and the testing results. The goal of this work is to illustrate a methodology to integrate the information derived from local, global, and geotechnical investigations into the finite element model of the masonry historical church of San Giovanni in Macerata, considering the Douglas-Reid model updating method. The PRiSMa laboratory of Roma Tre University carried out local investigations such as sonic tomography, video endoscopy and double flat jack tests, along with five ambient vibration tests that were processed through the operational modal analysis to extrapolate the dynamic properties of the building (modal frequency, modal shape vector and modal damping). The combined use of global, local and geotechnical information implemented in the methodology effectively reduced the uncertainties of the model and led the refinement and validation of the most relevant structural parameters
Integrated Modeling of Minerva Medica to Identify the Dynamic Effects of Rail-Traffic Vibrations
No full textA comprehensive study was carried out to integrate information from different sources and evaluate the effects of induced vibrations on a temple. Historical analysis was fundamental to interpreting the evolution of the construction and defining the HBIM. Experimental data were implemented in the FEM of the site, including the temple, its foundations, and the soil stratifications. Sensitivity analysis was carried out to identify the most influential parameters, which were calibrated to reduce error with the experimental frequencies. The FEM was further optimized with the Douglas–Reid method, considering, simultaneously, modal frequencies and deformations. Two different nonlinear dynamic analyses were performed; one analysis studied the effect on the temple of the dynamically moving load of the tram, and the other analysis studied the response of the temple to three-dimensional accelerations applied at the base. The drawbacks of each simulation were identified by comparing the numerical and experimental results
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Field testing for structural behavior of a stratified monumental complex over time: Palazzo Colonna-Barberini and Templum Fortunae Praeneste
No full textThe use of recent technology in heritage conservation incremented the knowledge on structures and materials, reducing the number of uncertainties. There are different activities required for an accurate structural assessment, the interconnection and coordination of the tasks and their results are the main challenges for the optimal exploitation of information. This research presents a holistic methodology to assess the seismic behavior of a complex and stratified historical construction. The assessment methodology includes historical survey, onsite testing for mechanical characterization, geometrical survey, visual inspection and recording to define a three-dimensional model and perform nonlinear structural analysis. The specific contribution of the paper is in the mechanical characterization through the integration of field local testing, as well as sonic tomography, double flat jacks, endoscopy, with virtual inspection assisted by photogrammetry. In this work, the methodology was applied to the Palazzo Colonna-Barberini in the Templum Fortunae Praeneste in Palestrina, Italy. The geometrical model of the actual complex was defined in the Building Information Model environment based on available survey and visual recordings. The structural model was derived from the geometry and integrated with the in-situ testing results, finally it was analyzed considering the nonlinear response of the materials
From Digital Restitution to Structural Analysis of a Historical Adobe Building: The Escuela José Mariano Méndez in El Salvador
No full textNowadays, the research in the fields of conservation and restoration is focusing on recording large amounts of data and information in order to obtain highly accurate surveys that include most details of constructions. Documenting and surveying are fundamental activities in achieving the successful preservation of cultural heritage, but also in implementing efficient strengthening interventions of structures. The applications of methods and techniques that link the disciplines of geometrical surveys and structural analyses are still fragmented, and further research is necessary to fully transfer site information into structural models. In this article, the authors propose a methodology with which to link different restoration fields, with the aim of highlighting the strengths and weaknesses of the interoperability between surveys (carried out through detailed restitution from point clouds), heritage building information modeling (HBIM), and structural analyses to connect three different disciplines. The goal is to find a synthesis model that brings together historical and geometric characteristics, but also physical–mechanical properties, for a structural evaluation through a finite element model (FEM). The case study of the Escuela José Mariano Méndez is analyzed, an extremely damaged historical adobe building in Santa Ana, the second largest city of El Salvador; it is considered fundamental to the national economy, particularly after the “coffee boom” in the late 1800s. The site, located near the historic center, is also known as “Antigua Escuela de Artes y Oficios” and embodies the architectural traditions of the region, being built in adobe and stone. Roma Tre University and the Secretaría de Cultura de la Presidencia (SECULTURA) are partners in this research project to document and restore the historical and cultural value of this site
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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