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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Origamis Matemáticos
No full textEsta trabajo aborda los origamis matemáticos, iniciando con la formalización del objeto, la
cual involucra conceptos de geometría diferencial y teoría de grafos principalmente, con lo cual
se define el proceso de plegado de un origami como una inmersión de un subconjunto de R2 en
R3. Las propiedades de la inmersión dependen fundamentalmente del patrón de pliegues sobre
el papel, los cuales determinan la forma final de la figura.
El estudio del plegado de un origami inicia sobre los vértices del patrón de pliegues, estos son
los puntos sobre la hoja en que se encuentran varios pliegues. Al caracterizarlos, encontramos
una serie de teoremas y resultados que nos permiten decidir si cada vértice individual podrá ser
plegado o no.
Al concluir esta caracterización, abordamos el problema de plegar plano el patrón de pliegues
completo, un problema computacionalmenteNP-difícil. Estudiaremos el problema de plegar una
tira de estampillas y estableceremos algunas de sus propiedades combinatorias. Pasaremos luego
al pliegue de Miura-Ori, un pliegue compuesto por vértices en el que confluyen cuatro pliegues.
Veremos que definir la orientación de todos los pliegues es un problema relacionado con el coloreado
de una cuadricula de 3 colores.
Definiremos entonces la complejidad computacional y enunciaremos el famoso problema de
P vs NP y finalizaremos con la demostración de que el problema de pliegue de un Origami es un
problema NP-completo.This work deals with mathematical origami, starting with the formalization of the object, which involves concepts of differential geometry and graph theory
concepts of differential geometry and graph theory mainly, with which the folding process of an origami is defined as an immersion of a subset of R2 in R2 into R2.
The folding process of an origami is defined as an immersion of a subset of R2 in R3.
R3. The properties of the immersion depend fundamentally on the pattern of folds on the paper, which determine the
the paper, which determine the final shape of the figure.
The study of the folding of an origami begins on the vertices of the fold pattern, these are
the points on the sheet where several folds meet. By characterizing them, we find a series of theorems and results
a series of theorems and results that allow us to decide if each individual vertex can be folded or not.
folded or not.
At the conclusion of this characterization, we address the problem of flat folding the complete fold pattern, a computationally NP-hard problem.
a computationally NP-hard problem. We will study the problem of folding a
and establish some of its combinatorial properties. We will then move on
to the Miura-Ori fold, a fold composed of vertices where four folds meet.
We will see that defining the orientation of all the folds is a problem related to the coloring of a 3-color grid.
of a 3-color grid.
We will then define the computational complexity and state the famous problem of
P vs NP and we will finish with the proof that the Origami folding problem is an NP-complete problem.
NP-complete problem.MatemáticoPregradoMatemáticas pura
Introducción a los origamis matemáticos y el paso de un origami plano a un origami en papel esférico
No full textEn esta entrega del Paskín Matemático, además de los artículos usuales de muy buena exposición matemática, tenemos la nueva sección Paskín-Challenge un problema matemático dirigido a los estudiantes de colegio, quienes podrán poner a prueba su creatividad, astucia y conocimientos matemáticos para intentar solucionarlo. Este problema viene con recompensas muy interesantes, ¡Anímate a resolverlo!Este trabajo explora el origami como una herramienta matemática, presentando su relación con la geometría y sus aplicaciones en la construcción de objetos imposibles con regla y compás, como el heptágono. A través del estudio de pliegues, se abordan conceptos como la combinatoria, los problemas NP-completos y las transformaciones de curvatura. Finalmente, se llega a la construcción de origami sobre una superficie esférica, aplicando proyecciones estereográficas.This work explores origami as a mathematical tool, showing its relationship with geometry and its applications in constructing objects impossible to build with compass and straightedge, such as the heptagon. Through the study of folds, concepts like combinatorics, NP-complete problems, and curvature transformations are discussed. Finally, origami on a spherical surface is constructed using stereographic projections
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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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