1,721,302 research outputs found
Chromoelectric flux tubes in QCD
No full textCardaci MS, Cea P, Cosmai L, Falcone R, Papa A. Chromoelectric flux tubes in QCD. Physical Review D. 2011;83(1): 014502.We analyze the distribution of the chromoelectric field generated by a static quark-antiquark pair in the SU(3) vacuum and revisit previous results for SU(2). We find that the transverse profile of the flux tube resembles the dual version of the Abrikosov vortex field distribution. We give an estimate of the London penetration length of the chromoelectric field in the confined vacuum. We also speculate on the value of the ratio between the penetration lengths for SU(2) and SU(3) gauge theories
Estudio de nanoparticulas de quitosano como agente antimicrobiano para el tratamiento preventivo de infecciones intramamarias en bovinos
Full text linkFil: Orellano, M. Soledad. Universidad Nacional de Villa María; Argentina.Fil: Bohl, Luciana P. Universidad Nacional de Villa María; Argentina.Fil: Breser, M. Laura. Universidad Nacional de Villa María; Argentina.Fil: Isaac, Paula. Universidad Nacional de Villa María; Argentina.Fil: Falcone, R. Darío. Universidad Nacional de Villa María; Argentina.Fil: Porporatto, Carina. Universidad Nacional de Villa María; Argentina
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
Soft computing techniques in structural and earthquake engineering: a literature review
No full textAlthough civil engineering problems are often characterized by significant levels of complexity, they are generally approached and solved by combining several practitioners’ skills, such as intuition, past experience, logical reasoning, mathematical elaborations, and physical sense. This is also the case of problems in structural and earthquake engineering whose solution is generally based on the so-called “engineer's judgment”. However, heuristic theories and algorithms within the framework of “soft computing” can provide a more rational and systematic way to approach and solve problems in these areas. As a matter of fact, the aforementioned algorithms have been recently utilized in several branches of engineering and applied sciences. This paper proposes a state-of-the-art review of the main applications of soft computing techniques to relevant structural and earthquake engineering problems. Specifically, the applications of fuzzy computing, evolutionary computing, swarm intelligence, and neural networks, as well as their hybrid combinations, are analyzed with the aim to examine their capability and limitations in modeling, simulation, and optimization problems
Matrix sketching for supervised classification with imbalanced classes
Full text linkThe presence of imbalanced classes is more and more common in practical applications and it is known to heavily compromise the learning process. In this paper we propose a new method aimed at addressing this issue in binary supervised classification. Re-balancing the class sizes has turned out to be a fruitful strategy to overcome this problem. Our proposal performs re-balancing through matrix sketching. Matrix sketching is a recently developed data compression technique that is characterized by the property of preserving most of the linear information that is present in the data. Such property is guaranteed by the Johnson-Lindenstrauss’ Lemma (1984) and allows to embed an n-dimensional space into a reduced one without distorting, within an ε-size interval, the distances between any pair of points. We propose to use matrix sketching as an alternative to the standard re-balancing strategies that are based on random under-sampling the majority class or random over-sampling the minority one. We assess the properties of our method when combined with linear discriminant analysis (LDA), classification trees (C4.5) and Support Vector Machines (SVM) on simulated and real data. Results show that sketching can represent a sound alternative to the most widely used rebalancing methods
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
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