1,721,142 research outputs found
Variational approach for the superfluid-insulator transition in the bosonic Hubbard model
No full textThe Cold Waters in the Port of Genoa (NW Mediterranean Sea) during the Marine Heatwave in Summer 2022
No full textExtreme weather phenomena have become more frequent and intense in recent decades in the context of climate change, and these include heat waves that affect both the atmosphere and seawater masses. In 2022, a summer marine heatwave (MHW) affected the entire Mediterranean Sea, and temperatures up to 5 °C above seasonal mean were reached in the Ligurian Sea in the NW part of the Mediterranean basin. In this scenario, the waters of the Port of Genoa (at the northern apex of the Ligurian Sea) distinguished themselves by maintaining lower temperatures than those of the open sea (a maximum gradient of −6.1 °C on 9 August 2022) after the passage of a fast-moving storm. In this study, the weather and sea parameters of the period (June–December 2022) are analysed to determine the phenomenon that caused the drop in temperatures in the water masses of the Port of Genoa. The sudden cooling of the water masses inside the port was caused by a heavy rainfall event in early August. Moreover, the isolation of the port water masses due to the weak dynamics of the period kept them stationary and locked inside the port. Seawater temperatures inside the port slowly rose again after the event, remaining cooler than outside temperatures throughout August (−0.3 °C on 31 August), reaching and exceeding outside temperatures on 3 September (26.4 °C), and remaining warmer until 3 November 2022 (21.5 °C)
Mott transition in bosonic systems: Insights from the variational approach
Full text linkWe study the Mott transition occurring for bosonic Hubbard models in one, two, and three spatial dimensions by means of a variational wave function benchmarked by Green's function Monte Carlo calculations. We show that a very accurate variational wave function, which is constructed by applying a long-range Jastrow factor to the noninteracting boson ground state, can describe the superfluid-insulator transition in any dimensionality. Moreover, by mapping the quantum averages over such a wave function into the partition function of a classical model, important insights into the insulating phase are uncovered. Finally, the evidence in favor of anomalous scenarios for the Mott transition in two dimensions is reported whenever additional long-range repulsive interactions are added to the Hamiltonian
Gestione dei siti delle reti di monitoraggio tramite GPS: l'esempio della rete sismica permanente dell'INGV-Osservatorio Vesuviano
No full textLe stazioni della Rete Sismica di Monitoraggio della Sezione “Osservatorio Vesuviano” dell’INGV
sono installate in luoghi talvolta difficili da raggiungere e lontani dalle strade di normale scorrimento, oppure
in strade di campagna non segnate sulle mappe [Buonocunto et al., 2001; Castellano et al, 2002a]. Per questi
motivi, non è sempre agevole raggiungerle anche con l’ausilio di un navigatore satellitare.
Inoltre, abitualmente l’itinerario per raggiungere una stazione è noto solo al personale che l’ha
installata o che ne ha curato la manutenzione per lunghi periodi [Castellano et al., 2002b].
Nasce quindi l’esigenza di archiviare e rendere disponibili le informazioni logistiche necessarie in
modo che tutto il personale impegnato nella gestione della Rete Sismica abbia gli strumenti necessari per
raggiungere le stazioni e poter eseguire rapidi interventi di manutenzioneIstituto Nazionale di Geofisica e VulcanologiaPublished1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveope
Gestione dei siti delle reti di monitoraggio tramite GPS: l'esempio della rete sismica permanente dell'INGV-Osservatorio Vesuviano
No full textLe stazioni della Rete Sismica di Monitoraggio della Sezione “Osservatorio Vesuviano” dell’INGV
sono installate in luoghi talvolta difficili da raggiungere e lontani dalle strade di normale scorrimento, oppure
in strade di campagna non segnate sulle mappe [Buonocunto et al., 2001; Castellano et al, 2002a]. Per questi
motivi, non è sempre agevole raggiungerle anche con l’ausilio di un navigatore satellitare.
Inoltre, abitualmente l’itinerario per raggiungere una stazione è noto solo al personale che l’ha
installata o che ne ha curato la manutenzione per lunghi periodi [Castellano et al., 2002b].
Nasce quindi l’esigenza di archiviare e rendere disponibili le informazioni logistiche necessarie in
modo che tutto il personale impegnato nella gestione della Rete Sismica abbia gli strumenti necessari per
raggiungere le stazioni e poter eseguire rapidi interventi di manutenzioneIstituto Nazionale di Geofisica e VulcanologiaPublished1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveope
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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