1,723,157 research outputs found
Integrals, Quantum Galois Extensions, and the Affineness Criterion for Quantum Yetter–Drinfel'd Modules
No full textAbstractIn this paper we shall generalize the notion of an integral on a Hopf algebra introduced by Sweedler, by defining the more general concept of an integral of a threetuple (H,A,C), where H is a Hopf algebra coacting on an algebra A and acting on a coalgebra C. We prove that there exists a total integral γ:C→Hom(C,A) of (H,A,C) if and only if any representation of (H,A,C) is injective in a functorial way, as a corepresentation of C. In particular, the quantum integrals associated to Yetter–Drinfel'd modules are defined. Let now A be an H-bicomodule algebra, HYDA the category of quantum Yetter–Drinfel'd modules, and B={a∈A|∑S−1(a〈1〉)a〈−1〉⊗a〈0〉=1H⊗a}, the subalgebra of coinvariants of the Verma structure A∈HYDA. We shall prove the following affineness criterion: if there exists γ:H→Hom(H,A) a total quantum integral and the canonical map β:A⊗BA→H⊗A, β(a⊗Bb)=∑S−1(b〈1〉)b〈−1〉⊗ab〈0〉 is surjective (i.e., A/B is a quantum homogeneous space), then the induction functor –⊗BA:MB→HYDA is an equivalence of categories. The affineness criteria proven by Cline, Parshall, and Scott, and independently by Oberst (for affine algebraic groups schemes) and Schneider (in the noncommutative case), are recovered as special cases
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
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
Unconventional methods of strategic distribution of the incertitude
Get PDFThe incertitude became a phenomenon in itself, and it can be due both to the theoretical errors of the deciding factor, and to the imprecision and lack of informational wholeness. In order to reduce the incertitude, one has crystallized several directions of strategic management, through which the managers could manifest a logically structured attitude in limit situations. Practically, we cannot speak about the exclusive use of a specific category of methods and techniques, as their combination is realized by referring to concrete decisional situations. A group of these methods according to their nature might be the following: technocratic methods, political methods, structural methods and methods of strategic redistribution of the incertitude. The last one which suppose the absorption of the incertitude, through less conventional instruments, different from those previously presented. In this paperwork, our purpose is to bring into focus several instruments, which allow the participants to the economical activities to be able to approach the incertitude in this field.uncertainty, strategic management, technocratic methods, political methods, structural methods , methods of strategic redistribution of the incertitude
The affineness criterion for Doi-Kopinnen modules
No full textLet (H, A,C) be a threetuple, where H is a Hopf algebra coacting
on an algebra A and acting on a coalgebra C, and M the category of representations of (H, A,C). Let z be a generalized grouplike element of (H, A,C) and B the subalgebra of z-coinvariants of the Verma structure A in M. We prove the following affineness criterion: if there exist a total z-normalized integral and if the canonical map is surjective, then the induction functor is an equivalence of categories
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
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