1,721,016 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
On the oblique reflection of a solitary wave
Full text linkThe solitary wave is a gravity water wave that travels with permanent shape and constant phase speed. It has long characteristic wavelength in the longitudinal direction and uniform transverse cross-sections. The present study is concerned with both the surface solitary wave on a homogeneous fluid and the internal solitary wave within a rigid-lid two-layer model. When two identical solitary waves with different propagation directions interact with each other, the collision problem can be converted to an oblique reflection problem replacing the symmetric plane with a rigid slip wall. This work focuses on a specific scenario called the Mach reflection. It is a strongly nonlinear phenomenon. Based on the existing theoretical and experimental research on the surface solitary wave, study has been extended to the internal solitary wave. The analyses are mainly based on the 3D fully nonlinear simulations utilising the CFD software OpenFOAM on UCL’s supercomputers. The third-order weakly nonlinear solution of an internal solitary wave has been derived and used to initialise the flow field in corresponding simulations. The code has been verified and validated through test cases on a single solitary wave and 2D collisions. The oblique reflection of a surface solitary wave with moderate amplitude has been simulated. Large-amplitude wave induced by the Mach reflection as observed in the experiment has been analysed. Two cases for internal solitary waves have been simulated where the incident wave amplitudes are small and moderate, respectively. The KP theory is only valid for the small-amplitude case. The wave profile of the moderate-amplitude case shows some distinct features that cannot be well predicted by the existing approximate models. Analyses have also been made on the physical quantities in terms of mass, momentum and energy to understand the transverse variation of the wave field. The research benefits the understanding of rogue waves induced by long wave interaction in order to protect life and property at coastal areas and in deep sea operations
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
Fully Nonlinear Numerical Simulations of Wave Interactions with Multiple Structures at Resonance
Full text linkA two-dimensional boundary element method (BEM) based on potential flow theory is adopted to study the wave interactions with multiple structures at resonance. Here resonance refers to the wave resonance which appears in the gaps between structures. The wave-structure interactions problems are simulated using a mixed Euler-Lagrangian scheme, with fully nonlinear boundary conditions applied on the instantaneous free surface and wetted body surface. The numerical scheme is verified through the simulations of wave interactions with a single body. Results show that both the free surface elevation and the hydrodynamic forces can be calculated accurately enough. The first primary study proposes a numerical approach to calculate the dominant natural frequencies in the gap based on the understanding of free liquid sloshing in a tank. The effectiveness of this approach is verified through the ‘response amplitude operator’ (RAO) analysis in terms of the gap free surface elevation. The natural frequencies are found for twin barges, with various gap widths and draughts. The effects of resonance on wave forces and elevations are also analysed. The second primary study considers the resonance induced by forced heave, sway and roll of body motion at various amplitudes. Particularly, second-order resonance, which is due to the sum or difference frequency, is found especially significant when the gap width over draught ratio is large. Second-order resonance can sometimes be as pronounced as, or even stronger than, classical first-order resonance. The third primary study concerns the wave resonance induced by nonlinear regular incident waves. For hydrodynamic interactions when the two bodies are both fixed, the free surface elevations are captured, particularly the standing wave trains formed in front of the upwave structure and sheltering effect behind the leeside structure. The nonlinearity associated with incident wave steepness is taken into consideration. Then second-order resonance in the gap caused by incident waves is studied. Finally, the wave resonance behaviour in the gap when the two bodies are freely floating under incident waves is analysed
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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