1,720,975 research outputs found
Objective Metrics Definition for QoE Assessment for Extended Reality Applications
No full textThe increasing advancement of Virtual and Augmented Reality technologies opens new research perspectives in various fields. While traditional multimedia content quality assessment has been extensively investigated, different issues need to be addressed for these novel technologies. In particular, evaluating the quality of experience must consider several aspects, involving, on the one hand, the quality of the displayed multimedia content and, on the other hand, human factors. Due to its inherent subjectivity, defining objective metrics for Quality of Experience is complex. This paper aims to frame the problem of objective Quality of Experience assessment and propose research directions to be pursued in this field
Overview of the dynamic approach for the full and partial interaction analysis within the generalised beam tehory (GBT)
No full textGeneralised Beam Theory (GBT) is an efficient and elegant method of analysis to describe the behaviour of steel and composite members that include thin-walled sections. This paper presents an overview of the work carried out to date on a particular GBT approach whose distinguishing feature is to use dynamic analyses for the identification of a suitable set of deformation modes that, in the general version of the methodology, includes conventional, extension and shear modes. With this approach, the deformation modes are selected as the dynamic eigenmodes of an unrestrained planar frame representing the cross-section. The initial formulations of this approach considered the full shear interaction analysis of steel and composite members. These were later extended to account for the partial interaction that can exist within parts of two-layered and multi-component sections. Numerical examples are presented to highlight the ease of use of the GBT formulation and the accuracy of the numerical results is validated against those calculated with a shell finite element model developed in ABAQUS
Partial interaction analysis of multi-component members within the GBT
No full textThis paper presents a novel approach that describes the first-order (linear elastic) partial interaction analysis of members formed by multi-components based on the Generalised Beam Theory (GBT). The novelty relies on its ability to accurately model the partial interaction between the different components forming the cross-section in both longitudinal and transverse directions as well as to consider the cross-sectional deformability. The GBT deformations modes, that consist of the conventional, extensional and shear modes, are determined from the dynamic analyses of the cross-section represented by a planar frame. The partial interaction is specified at each connection interface between two adjacent elements by means of a shear deformable spring distributed along the length of the member. The ease of use of the model is outlined by an application performed on a multi-component member subjected to an eccentric load. The values calculated with an ABAQUS finite element model are used to validate the proposed method. The results of the numerical applications outline the influence of specifying different rigidities for the interface shear connection and in using different order of polynomials for the shape functions specified in the finite element cross-section analysis
Partial interaction analysis of multi-component members with the D-GBT approach
No full textThis paper presents a partial interaction model for the analysis of multi-component members that accounts for the in-plane deformability of the cross-section. The D-GBT approach is formulated extending the applicability of the dynamic cross-sectional procedure developed for open, closed or partially-closed thin-walled cross-sections within the framework of the Generalised Beam Theory and introducing a simpler procedure for the identification of the deformations modes, i.e. conventional, extension and shear modes, to be used for the GBT analysis. The proposed partial interaction enables relative movements to take place in the plane of the interface between adjacent components in the longitudinal and transverse directions. The ease of use of the proposed method is outlined by means of an application performed on a multi-component beam subjected to an eccentric load. Its accuracy is validated against numerical solutions obtained with a shell finite element model developed in ABAQUS/Standard
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
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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