1,720,960 research outputs found
Distortion Of Ampère's Electromagnetic Work In The Textbooks [distorção Da Obra Eletromagnética De Ampère Nos Livros Didáticos]
No full textWe analyze how some representative textbooks present Ampère's electromagnetic work. We show that this information is distorted and does not correspond to the historical-facts. This leads to an erroneous view about the evolution of physics and about the formulation of its laws. Copyright by the Sociedade Brasileira de Física.2916570Kuhn, T.S., (1978) A Estrutura das Revoluções Científicas, , Editora Perspectiva, São Paulo, 2a ediçãoH.C. Ørsted, Cad. Hist. Fil. Ci. 10, 115 (1986)E.M. Purcell, Curso de Física de Berkeley, v. 2: Eletricidade e Magnetismo (Editora Edgard Blücher, São Paulo, 1988), 3a reimpressãoTipler, P.A., (2000) Física, 2. , Eletricidade, Magnetismo e Óptica Editora LTC, Rio de Janeiro, 4a edTricker, R.A.R., (1965) Early Electrodynamics - The First Law of Circulation, , Pergamon Press, OxfordHofmaim, J.R., (1996) André-Marie Ampère - Enlightenment and Electrodynamics, , Cambridge University Press, CambridgeAssis, A.K.T., (1995) Eletrodinâmica de Weber, , Editora da Unicamp, CampinasAmpère, A.-M., (1990) Théorie Mathématique des Phénomènes Électro-dynamiques Uniquement Déduite de l'Experience, , Editions Jacques Gabay, SceauxR.P. Feynman, R.B. Leighton and M. Sands, The Feynman Lectures on Physics, v. 2: Mainly Electromagnetism and Matter (Addison-Wesley, Reading, 1972), 7a. impressãoReitz, J.R., Milford, F.J., Christy, R.W., (1982) Fundamentos da Teoria Eletromagnética, , Editora Campus, Rio de Janeiro, 3a edHauser, W., (1971) Introduction to the Principles of Electromagnetism, , Addison-WesleyWangsness, R.K., (1986) Electromagnetic Fields, , John Wiley & Sons, Hoboken, 2a edJackson, J.D., (1999) Classical Electrodynamics, , John Wiley Sons, New York, 3a edHalliday, D., Resnick, R., Walker, J., (1996) Fundamentos de Física, v. 3: Eletromagnetismo, , Editora LTC, Rio de Janeiro, 4a edWhittaker, E.T., A History of the Theories of Aether and Electricity (1973) The Classical Theories, 1. , Humanities Press, New YorkHalliday, D., Resnick, R., Walker, J., (2003) Fundamentos de Física, v. 3: Eletromagnetismo, , Editora LTC, Rio de Janeiro, 6a edR.D.A. Martins, Rev. Bras. Ens. Fis. 27, 11 (2005)Griffiths, D.J., (1999) Introduction to Electrodynamics, , Prentice Hall, Englewood Cliffs, 3a e
Distortion of Ampère's electromagnetic work in the textbooks
No full textWe analyze how some representative textbooks present Ampère's electromagnetic work. We show that this information is distorted and does not correspond to the historical facts. This leads to an erroneous view about the evolution of physics and about the formulation of its laws.Analisamos como alguns livros didáticos representativos apresentam a obra eletromagnética de Ampère. Mostramos que as informações apresentadas são distorcidas e que não correspondem à realidade histórica. Isto leva a uma visão errônea da evolução da física e da formulação de suas leis.657
Oersted's Experience In The Classroom [experiência De Oersted Em Sala De Aula]
No full textIn 1820 Oersted observed the deflection of a small magnet placed close to a wire carrying a steady current. This fundamental discovery unleashed a series of researches which led to the unification of the electric and magnetic phenomena. The goal of this paper is to contribute to show the importance of Oersted's experiment. It is made a short historical contextualization of this experiment. It is described a modern reproduction of the procedures and observations of Oersted utilizing low cost materials. Copyright by the Sociedade Brasileira de Física.2914151Grant, E., (1981) Dictionary of Scientifc Biography, 9, pp. 532-540. , edited by C.C. Gillispie Charles Scribner's Sons, Nova IorqueGilbert, W., (1978) Great Books of the Western World, 28, pp. 1-121. , Encyclopaedia Britannica, ChicagoTricker, R.A.R., (1965) Early Electrodynamics - The First Law of Circulation, , Pergamon Press, OxfordR.D.A. Martins, Cad. Hist. Fil. Ci. 10, 89 (1986)Hofmann, J.R., (1996) André-Marie Ampère - Enlightenment and Electrodynamics, , Cambridge University Press, CambridgeB.C. Ørsted, Cad. Hist. Fil. Ci. 10, 115 (1986)Ferreira, N.C., (2001) Ciência Hoje ria Escola, 12, p. 18A. Medeiros, Rev. Bras. Ens. Fis. 24, 353 (2002)Teixeira, W., Toledo, M.C.M., Fairchild, T.R., Taioli, F., (2000) Decifrando a Terra (Oficina do Textos, , São Paulo, Dado obtido do mapa de intensidade do campo geomagnétic
Oersted's experience in the classroom
No full textIn 1820 Oersted observed the deflection of a small magnet placed close to a wire carrying a steady current. This fundamental discovery unleashed a series of researches which led to the unification of the electric and magnetic phenomena. The goal of this paper is to contribute to show the importance of Oersted's experiment. It is made a short historical contextualization of this experiment. It is described a modern reproduction of the procedures and observations of Oersted utilizing low cost materials.Em 1820 Oersted observou a deflexão de um pequeno ímã colocado próximo a um fio com corrente constante. Esta descoberta fundamental desencadeou uma série de pesquisas que levou à unificação dos fenômenos elétricos e magnéticos. Este artigo visa contribuir para o resgate da relevância da experiência de Oersted. É feita uma breve contextualização histórica desta experiência. Descreve-se uma reprodução moderna dos procedimentos e observações de Oersted com materiais de baixo custo.415
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
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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