1,721,003 research outputs found
Un tesoro ritrovato: dal rilievo alla rappresentazione
No full textIl volume Un tesoro ritrovato. Dal rilievo alla rappresentazione rappresenta il catalogo della mostra omonima, promossa dall’Agenzia del Territorio sotto l’Alto Patronato del Presidente della Repubblica Italiana si è svolta a Roma, nel Complesso Monumentale del Vittoriano a Roma, dal 26 novembre 2009 al 10 gennaio 2010 Il volume rivolto non solo agli operatori e cultori del settore, ma anche a un pubblico più vasto, offre la possibilità di compiere un affascinante viaggio alla scoperta dei diversi saperi, professionalità e competenze dell’Agenzia del Territorio attraverso una narrazione che ripercorre le tappe della storia della cartografia e di quegli insiemi di conoscenze scientifiche, tecniche e artistiche a essa connesse, che hanno accompagnato, e spesso anche stimolato, l’evoluzione economica e il progresso tecnologico della società. Una breve premessa storica, partendo dall’epoca preistorica, passando per la civiltà egizia e proseguendo nell’antica Grecia e nell’epoca romana fino alla Civiltà dei Lumi, consente di esaminare alcuni pezzi originali tra cui il “Cubito di Imen-m-ipet” proveniente dal Museo delle Antichità Egizie di Torino e la “Groma” del Museo Archeologico Nazionale di Napoli. Il racconto della nascita dei catasti geometrico-particellari nel XVIII e XIX secolo e una panoramica su alcune cartografie elaborate prima della promulgazione della legge istitutiva del Catasto Italiano, del 1886, illustrano il patrimonio dell’Agenzia del Territorio. In particolare, documenti del “catasto teresiano”, napoleonico, pontificio, franceschino e altri catasti ottocenteschi, cui sono state affiancate straordinarie tavole di cabrei e atlanti, hanno fornito alcuni significativi esempi dell’accuratezza del rilevo e soprattutto della raffinatezza della rappresentazione, sempre presente anche nella cartografia catastale.Percorrendo le varie tappe storiche si giunge, attraverso l’esame di affascinanti strumenti di rilievo topografico e aerofotogrammetrico e di calcolo e archiviazione, fino all’introduzione dell’informatica, che caratterizza l’epoca più recente. Il percorso infine si conclude affrontando la questione della gestione moderna della cartografia catastale e della gestione informatizzata del processo di aggiornamento del Catasto, mettendo in evidenza l’attualità e lo sviluppo futuro delle attività dell’Agenzia, attraverso la presentazione della procedura Pregeo e della consultazione telematica del Catasto
A new FQHE trial wave function for planar and spherical geometry
No full textWe propose new trial wave functions generalizing the Laughlin wave function for the Fractional Quantum Hall Effect to arbitrary fractional filling. Starting from a systern of N interacting electrons with a "colour" quantum number, we obtain, by an adiabatic interpolation through anyon hamiltonians, a trial wave function for identical electrons both for planar and spherical geometry. Monte Carlo sinmlations of the equivalent classical plasma give ground state energies confirming the reliability of the proposed wave fimctions
Adiabatic heuristic construction of trial wave functions for quantum Hall states at arbitrary fractional fillings
No full textStarting from a lowest Landau level filled with several electron species, adiabatic interpolation through anyon hamiltonians is considered. The antisymmetrized final states are explicit trial wave functions for identical electrons, depending on three integer parameters, and generalize the Laughlin wave function to arbitrary fractional fillings. Space homogeneity is proved by Laughlin's classical plasma argument, which is exploited also to estimate the energy by Monte Carlo simulations. Numerical results are consistent with energies reported by other authors using much less simple trial wave functions
A generalized FQHE trial wave function on spherical geometry
No full textUsing Haldane's spherical model, new microscopic trial wave functions originally built on disk geometry are mapped onto the sphere. These wave functions were obtained for arbitrary fractional filling by adiabatic interpolation through anyon Hamiltonians. Monte Carlo methods have been employed to evaluate the ground state energy at different fillings using up to 128 electrons on a sphere. Results are consistent with extrapolation of exact system diagonalization and earlier Monte Carlo calculations
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
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