1,721,002 research outputs found
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
Operational domain theory and topology of sequential functional languages
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
Exact real calculator for everyone
No full textThis paper was presented at the Joint Session of the 18th Asian Technology Conference in Mathematics and 6th Technology and Innovations in Mathematics Education (2013) held at Mumbai, India from 7 – 11 Dec 2013Despite its simplicity and versatility, the well-known Floating Point System (FPS) has a serious shortcoming: the finite nature of a computer makes rounding-off inevitable. Because of this, FPS can sometimes lead to serious computational errors, i.e., a small round-off error due to truncation can cause a large deviation in the output in iterations within chaotic systems. This paper bridges the gap between theory and practice of Exact Real Arithmetic (ERA), and reports on the design and implementation of a user-friendly scientific calculator ERCE using HASKELL, capable of ERA. With a functional-programming slant, we use ERCE as a channel for the technology of ERA to reach out to a wider community: even a school student can use it.Published versio
Computation as a big idea in mathematics
No full textCharles (2005) defines a Big Idea in Mathematics to be “a statement of an idea that is central to the learning of mathematics, one that links numerous mathematical understandings into a coherent whole” (p. 10). Therein, Charles listed a total of 21 Big Ideas – acknowledging the impossibility that all mathematicians and mathematics educators can agree on these – with the hope that they can be a starting point to initiate conversations. In this paper, we propose that ‘Computation’ can be added to this list of big ideas in mathematics and give compelling reasons to support our proposal. Additionally, we describe some implications of such an inclusion with particular emphasis on teaching and learning of mathematics at schools.Published versio
Theory of frames
No full textThe study of frames can be traced back to as early as Wallman's work in 1938, in which he initiated the study of topological properties from a lattice-theoretical point of view. C. Ehresmann and J. Benabou firstly regarded complete Heyting algebras as generalised topological spaces in their own right. Such lattices were called 'local lattices'. It was Dowker and Strauss who first used the term 'frame' in their systematic study of such structure. After that many people have made a significant contribution to the study of frames (or locales: the opposite categorical version of frames), such as Isbell, Banaschewski, Joyal, Johnstone, Simmons, etc.On the other hand, inspired by frames, several types of generalised frames have been introduced and studied in relatively recent times. Three notable examples of generalised frames are σ-frames, κ-frames and preframes. The κ-frames, which were first systematically studied by Madden recently, generalise both frames and σ-frames. While preframes, which have been carefully studied by Johnstone and Vickers, belong to a different type of generalisation.The emergence of Ζ-continuous posets which unifies various "continuous" structures and discussed most of their basic properties. In 1992, D. Zhao launched a similar programme in attempt to make a uniform approach to various frame-like structure by introducing Ζ-frames. The approach turns out to be very convenient and effective for further categorical treatment.Category theory is an economical tool that provides a common framework for many branches of mathematics, especially in topology and algebra. In the process of my study of generalised frames, categorical concepts are employed extensively.My three-years course of study has been constantly motivated by many important papers and publications. The first one, Nuclearity by K.A. Rowe ([19]), is an important paper. The concept of nuclearity aims to characterise finite-dimensionality in symmetric monoidal closed categories. Rowe made a systematic study of nuclearity via many different examples.The second one is on Nuclearity in the category of complete semilattices by D.A. Higgs and KA. Rowe ([11]). This paper demonstrated that the nuclear objects of the category of complete lattices are precisely the completely distributive lattices (CDL for short). In lattice theory, completely distributive lattices have always attracted special attention. Thus, the CDLs, became one of the most important classes of lattices and have been extensively studied by many authors. This fact, together with many other examples in [19], lead to the following question: Are nuclear objects projective? The first part of my project indicates a positive answer with some minimal assumptions.The book A compendium of continuous lattices ([10]), written by six expert lattice-theorists (G. Gierz et al.), is an excellent guidebook for me in learning the ropes of continuous lattice theory. Difficult book it is indeed, but it gives a concise and in-depth treatment of continuity in lattice theory. It gives me a very sound foundation that prepares me to understand D.Zhao's approach to generalised frame theory via Ζ-theory.The doctoral dissertation Generalisation of Continuous Lattices and Frames by D.Zhao ([21]) gives a detailed and clear introduction of Ζ-frames. It opened up a completely new and exciting area of research for me because the concepts and mathematical concepts that arise from Ζ-frames are very rich.One natural question is whether the concept of nuclearity may be defined for the category of Ζ-frames. The very first step is, of course, to understand how tensor products may be set up in order that we have an autonomous categorical structure.So the third paper Tensor products and bimorphisms by B.Banaschewski and E. Nelson ([1]) provides very handy information about conditions which will guarantee the existence of tensor multiplication in a concrete category.Despite the promises that the Ζ-theory seemed to offer, there is one main obstacle that hinders a natural autonomous structure on ZFrm : It is not even clear how the internal hom may be established, let alone the tensor product. However, in the categories of complete join-semilattice, frames and preframes, various constructions have been made to show that they are autonomous categories (see [11], [16] and [17]). This branches off to two alternatives. One of them is to simplify the problem and focus on a less intricate category, namely the category of the Ζ-complete posets and the morphisms that preserve Ζ-sups. Although the internal hom exists, we still cannot enjoy the luxury of having a tensor product.Another approach, which may be more difficult, is to generalise P. Johnstone's work ([16]). It seems that we can take advantage of the monadic nature of the category of Ζ-frames. Much work, involving Universal Algebra and Proof Theory, remains to be done in this direction.The sixth is the paper On projective z-frames by D.Zhao ([23]) which characterises the E-projective objects in the category zFrm in adjunction to the category of semilattices. This leads to the study of E-projective objects in the category of frames in adjunction to the category of Ζ-frames. While working furiously at this problem, I ventured into the topic of generalised Scott-topology
Characterising E-projectives via Co-monads
No full textAbstractThis paper demonstrates the usefulness of a comonadic approach to give previously unknown characterisation of projective objects in certain categories over particular subclasses of epimorphisms. This approach is a simple adaptation of a powerful technique due to M. Escardó which has been used extensively to characterise injective spaces and locales over various kinds of embeddings, but never previously for projective structures. Using some examples, we advertise the versatility of this approach – in particular, highlighting its advantage over existing methods on characterisation of projectives, which is that the comonadic machinery forces upon us the structural properties of projectives without relying on extraneous characterisations of the underlying object of the co-algebra arising from the comonad
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