1,720,975 research outputs found
Influenza dei fattori climatici e topografici sul regime di frequenza delle piene nel Triveneto
No full textIl presente studio prende in esame il Triveneto, vasta area geografica comprendente le Alpi Orientali italiane, ed ha tre obiettivi principali: (1) valutare l’influenza dei fattori climatici e di scala sul regime di frequenza delle piene; (2) verificare la possibile presenza di alterazioni del regime di frequenza dei massimi annuali di portata al colmo di piena; (3) sviluppare una procedura aggiornata per la stima delle piene di progetto in Triveneto impiegando tecniche di raggruppamento di bacini basate su criteri di similitudine idrologica col bacino di interesse (approccio della regione di influenza, Region of Influence, RoI). Lo studio è pervenuto alle seguenti conclusioni: (1) l’influenza dei fattori climatici e topografici sul regime di frequenza delle piene in Triveneto risulta simile a quella recentemente osservata a scala europea in analoghi contesti morfologici e climatici; (2) nonostante non si siano riscontrate evidenze di alterazioni significative e generalizzate del regime di frequenza delle piene, le indagini hanno messo in risalto come un singolo anno caratterizzato da piene eccezionali possa influenzare notevolmente i modelli regionali di frequenza delle piene; (3) infine, è confermata per l’area in esame una marcata eterogeneità spaziale del regime di frequenza delle piene; in quest’ottica si raccomanda per essa un aggiornamento della procedura di riferimento per la stima della portata di progetto sulla base di procedure analoghe al RoI, che consentano di rappresentare l’influenza di fattori climatici e topografici sul regime di frequenza degli estremi idrometrici.Our study focuses on Triveneto, a broad geographical region which includes the Italian Eastern Alps. The objective of our study is threefold: (1) to inspect climatic and scale controls on flood frequency regime; (2) to verify the possible presence of changes in flood frequency regime by applying non-parametric statistical tests to annual maximum series of flood peak discharges and by evaluating the possible presence of changes in time of regional statistics of hydrometric extremes; (3) to develop an updated reference procedure for design flood estimation in Triveneto by using a focused-pooling approach (i.e. Region of Influence, RoI). Our study leads to the following conclusions: (1) climatic and scale controls on flood frequency regime in Triveneto are similar to the controls that were recently found at European scale in an analogous morpho-climatic context; (2) although we found no significant uniform changes in the flood frequency regime in the study area, our analyses highlight how a single year characterized by extreme floods can have a remarkable influence on regional flood frequency models; (3) finally, our analyses indicate for the study region a high heterogeneity degree in the flood frequency regime; therefore we recommend an update of the existing reference procedure for design flood estimation, referring to procedures similar to the RoI approach, which properly represents climate and scale controls on flood frequency regime
The value of spatial correlation in Regional Flood Frequency Analysis: Generalized Least Squares versus Top-Kriging
No full text
RECENTI CAMBIAMENTI NELLA STAGIONALITÀ E NEL REGIME DI FREQUENZA DEGLI ESTREMI PLUVIOMETRICI SUB‐GIORNALIERI E POTENZIALE RUOLO SULLE DINAMICHE DEL RISCHIO ALLUVIONALE IN EMILIA‐ROMAGNA
No full text
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
Assimilazione geostatistica dell'informazione idrometrica nelle simulazioni idrologiche a macro-scala
No full textDispelling 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
- …
