1,721,101 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
3DGIS representation for supporting seismic mitigation policies at urban scale: The case study of Lisbon
No full textThe structural capacity of buildings to guarantee acceptable safety levels during and after earthquakes has significant influence on community and urban resilience. The paper presents the implementation in the Geographic Information System (GIS) of the data related to the expected seismic damage scenarios for some existing residential mixed masonry-reinforced concrete buildings located in Lisbon area. At city scale, such kind of representation can effectively support the seismic risk management including the design of mitigation policies. In fact, the spatial representation of results provides clear and global overview of the area under analysis, understandable not only to scientist and engineers, but also to the city councils and population. Damage scenario are defined on basis on fragility curves computed analytically through a nonlinear static approach by focusing the attention only to the in-plane global response and considering also the aggregate effect. The application to Lisbon city shows that the expected level of the damage consequent to the code action is high for the structural typology under investigation
In-plane cyclic tests of strengthened rubble stone masonry
No full textThis paper focuses on the in-plane behaviour of rubble stone masonry with lime mortar strengthened with different solutions. For that, 12 rubble stone masonry wall specimens, with construction features typical of ancient historic buildings of Southern Portugal and Mediterranean countries, were subjected to in-plane quasi-static cyclic tests. The applied retrofit solutions are specific for historic masonry buildings, such as the injection of mortar and FRCM systems, with glass and carbon meshes. The main experimental results obtained are presented through envelope curves, in terms of resistance, deformation capacity, and deformed shapes. Moreover, dissipated energy is also commented on. Horizontal drift results are compared and analysed together with the ones obtained in the literature for equivalent strengthening solutions in masonry walls
Sensitivity analyses of the seismic performance of mixed masonry-RC buildings: The "Rabo de Bacalhau" building type in Lisbon
No full textThis paper is focused on the sensitivity analyses as tool to identify the main parameters that affect the seismic response of one type of the old mixed masonry-reinforced concrete buildings in Lisbon. The main purpose of this analyses is to compare the seismic behavior of an existing building, representative of this typology, as a function of the changes of its properties with respect to the response of a reference model calibrated from available standards and experimental tests. The seismic performance is evaluated through the well-recognized N2 method and the influence of different material properties are taken into the account:Young modulus, shear modulus, shear strength and compressive strength of the masonry wall, as well as the shear modulus for timber floors. The equivalent frame model approach is used to define the 3D representation of the structure
Definition of fragility curves through nonlinear static analyses: procedure and application to a mixed masonry-RC building stock
No full textSeismic risk analyses at large scale represents a fundamental support to effective mitigation policies. Evaluating fragility curves able to capture the huge variety of existing buildings is one key point of this analysis. Within this context, this paper proposes a procedure for the evaluation of the fragility curves that aims to limit the computational effort without losing the reliability of the achieved results. This is reached through the execution of a limited number of nonlinear static procedures based on the use of the sensitivity analysis carried out according to the simplified star design with central point approach. The main strength of the procedure is the ability to explicitly quantify the various contributions of uncertainty to the dispersion, associated to those on the structural capacity (taking into account both aleatory and epistemic sources) and on the seismic input. As known, the adoption of a nonlinear static approach for the seismic assessment implies various assumptions, such as the load pattern applied, the criteria adopted to compare the capacity and the demand, and the definition of the damage levels. All these issues potentially affect the reliability of the final fragility curves, which are defined through a proper combination of such various options or they can be selected based on the ones more representative of the expected behaviour of the class. To improve this aspect, the evidences from nonlinear dynamic analyses are used. The feasibility and effectiveness of the procedure is duly demonstrated in this paper through its application to a building stock typology, consisting of existing mixed masonry-reinforced concrete structures, representative of one of the largest portions of the existing residential buildings in Lisbon. The attention is focused only to the global in-plane behaviour by adopting as modelling approach the equivalent frame method, that has been proven particularly efficient and accurate enough in representing the nonlinear behaviour of the examined structures
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
- …
