1,721,998 research outputs found
A remark on a Diophantine equation of S. S. Pillai
No full textsummary:S. S. Pillai proved that for a fixed positive integer , the exponential Diophantine equation , , has only finitely many solutions in integers and . We prove that when is of the form , the above equation has no solution in integers and with
On Some Exponential Equations of S. S. Pillai
No full textAbstractIn this paper, we establish a number of theorems on the classic Diophantine equation of S. S. Pillai, ax – by = c, where a, b and c are given nonzero integers with a, b ≥ 2. In particular, we obtain the sharp result that there are at most two solutions in positive integers x and y and deduce a variety of explicit conditions under which there exists at most a single such solution. These improve or generalize prior work of Le, Leveque, Pillai, Scott and Terai. The main tools used include lower bounds for linear forms in the logarithms of (two) algebraic numbers and various elementary arguments.</jats:p
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
Conversational Agents, Natural Language Processing, and Machine Learning for Psychotherapy
No full textMental illness is one of the most pressing public health issues of our time. Economic constraints, social stigma, and scarce availability of professionals require, on one hand, to augment clinical support and quality, and on the other hand, to create instruments able to augment the treatments and to enrich training and supervision methods. The use of Conversational Agents (CAs) in the field of mental health and psychotherapy is in the early stages of development. This chapter helps to understand the reasons of this delay and suggests some strategies that could be adopted to compensate for it. The chapter analyzes and discusses the most recent literature dealing with CAs, Natural Language Processing (NLP), and Machine Learning (ML) supporting the mental health domain, with a special focus on psychotherapy and psychological support, evaluation of strategies and systems, analysis of clinical interactions, and training and supervision of professionals. Moreover, the chapter discusses several models available as research frameworks, prototypical solutions, or commercial systems. The aim of the proposed reasoned survey is twofold: to allow the enrichment of clinical interventions, and to invite NLP and ML experts to consider this applicative domain as particularly important for the development of CAs. Human-like interaction – imitated or complemented by CAs – is a central aspect of this chapter. In particular, the relevance is clear of empathic-oriented behaviors, sentiments (and emotion analysis), prosodic and “mirroring” competencies, in the context of evidence-based protocols that try to ensure the efficacy of augmented psychotherapeutic strategies and the subjects' and therapists' adherence to them
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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