1,721,007 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
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
Nuclear magnetic resonance (NMR) metabolomics: current applications in equine health assessment
Full text linkMetabolomics can allow for the comprehensive identification of metabolites within biological systems, at given time points, in physiological and pathological conditions. In the last few years, metabolomic analysis has gained popularity both in human and in veterinary medicine, showing great potential for novel applications in clinical activity. The aim of applying metabolomics in clinical practice is understanding the mechanisms underlying pathological conditions and the influence of certain stimuli (i.e., drugs, nutrition, exercise) on body systems, in the attempt of identifying biomarkers that can help in the diagnosis of diseases. Proton Nuclear Magnetic Resonance spectroscopy (1H-NMR) is well tailored to be used as an analytical platform for metabolites' detection at the base of metabolomics studies, due to minimal sample preparation and high reproducibility. In this mini-review article, the scientific production of NMR metabolomic applications to equine medicine is examined. The research works are very different in methodology and difficult to compare. Studies are mainly focused on exercise, reproduction, and nutrition, other than respiratory and musculoskeletal diseases. The available information on this topic is still scant, but a greater collection of data could allow researchers to define new reliable markers to be used in clinical practice for diagnostic and therapeutical purposes
A Numerical Study of the Aerodynamic Consequences of Blade Leading-Edge In-Service Erosion on the Performance Characteristics of a Coal Fired Boiler Induced-Draft Fan
No full textDispelling 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
Numerical investigations on the aerodynamic influence of eroded leading-edge geometry on boiler fan performance
No full textAxial fans handling high temperatures or corrosive gases in power stations are exposed to erosion phenomena that result in increased surface roughness or modifications of blade section shapes. Erosion results in the reduction of blade chord and effective camber, thus altering the turning flow and the actual blade load. Consequently, aerodynamic performance gradually reduces, and in some circumstances reduces drastically as the rotor's structural integrity is undermined. The present paper investigates the influence of leading edge geometry in a high pressure boiler fan designed for forced-draft application in coal fired power plant. To this end, a comparative analysis considers: (i.) the datum blade section, (ii.) a modified blade. The datum blades represent the original blade geometry. The modified blade represents eroded blade geometry, as measured after in-service operation including suction and pressure side wear. The study concludes with (iii.) a re-shaped blade. The authors carried out the simulations using an in-house developed multilevel parallel, finite element RANS solver, with the adoption of non-isotropic turbulence closure. The authors investigated rotor aerodynamics by comparing the pressure fields and the boundary layer development on the blade suction surfaces that limit the pressure rise and flow turning
Signal-flow-graph derivation of on-line gradient learning algorithms
No full textIn this paper, making use of the signal-flow-graph (SFG) representation and its known properties, we derive a new general method for backward gradient computation of a system output or cost function with respect to past (or present) system parameters. The system can be any causal, in general nonlinear and time-variant dynamic system represented by a SFG, in particular any feedforward or recurrent neural network. In this work we use discrete time notation, but the same theory holds for the continuous time case. The gradient is obtained by the analysis of two SFGs, the original one and its adjoint. This method can be used both for online and off-line learning. In the latter case using the mean square error cost function, our approach particularises to Wan's method (1996) that is not suited for online training of recurrent networks. Computer simulations of nonlinear dynamic systems identification will also be presented to assess the performance of the algorithm resulting from the application of the proposed method in the case of locally recurrent neural networks
- …
