1,721,793 research outputs found
Indagine sulla protezione catodica all’interno di scaldacqua domestici per la produzione di acqua sanitaria
Full text linkIn questo lavoro di ricerca, è stato studiato il grado di protezione catodica offerto da un sistema combinato di anodi, costituito da un anodo sacrificale di magnesio e da un anodo a corrente impressa di titanio attivato, installati all’interno di un boiler di capacità volumetrica di 60 L e 100 L. L’efficacia di tale sistema è stata esaminata in funzione della conducibilità specifica dell’acqua (50 µS/cm, 250 µS/cm, 500 µS/cm, 750 µS/cm, 1000 µS/cm, 1180 µS/cm e 3260 µS/cm) e della temperatura (20 °C, 50 °C e 75 °C). A tale scopo, sono state realizzate sei sonde poste nei punti critici del serbatoio come le zone di saldatura. Esse hanno permesso di studiare l’efficacia della protezione catodica del boiler “in modo localizzato”, tramite misure di potenziale relative a difetti simulati. Allo scopo è stata sviluppata una stazione di monitoraggio attraverso cui venivano misurati in continuo i potenziali delle sei sonde, della flangia porta-resistenza elettrica e del serbatoio del boiler. Da questo studio, è emerso che il sistema di protezione esaminato ha protetto tutte le componenti metalliche del boiler, in tutte le condizioni sperimentali. Inoltre, è stata osservata anche la sovrapotezione del sistema esaminato con probabile sviluppo di idrogeno. Al fine di eliminare questo problema e di garantire una buona gestione della protezione catodica del boiler, è possibile utilizzare il sistema combinato ma con l’anodo di titanio operante a corrente più bassa o utilizzando, per l’anodo sacrificale di magnesio, altri tipi di leghe come leghe di zinco adatte alle alte temperature (quindi che non subiscano l’inversione di coppia tipica degli anodi di zinco) e leghe di alluminio contenenti percentuali di magnesio ed indio; queste sono leghe con potenziali di lavoro più elevati rispetto alle tipiche leghe di magnesio impiegate all’interno dei serbatoio ad accumulo, e quindi possono dare meno problemi di sovraprotezione.
Infine, in questo studio sono stati proposti due approcci di calcolo, uno empirico e uno agli elementi finiti, che si sono dimostrati dei validi strumenti per la progettazione dei sistemi di protezione catodica
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
Verso la disfatta. Saggio di commento a Silio Italico, Punica 5, 1-343
No full textLa tesi offre un commento ai vv. 1-343 del V libro dei Punica, dedicato alla battaglia del lago Trasimeno, in cui l'esercito di Flaminio cade nella trappola tesa da Annibale ed è annientato. Il commento è preceduto da un'introduzione che affronta alcuni aspetti generali relativi al poema (datazione, struttura, elementi di attualità politica relativi all'età flavia) e si concentra poi sul libro V, analizzandone temi, personaggi, modelli e stile
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
BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO
Full text linkThe principal research effort for Year 1 of the project is data compilation and the determination of the tectonic and depositional histories of the North Louisiana Salt Basin. In the first three (3) to six (6) months of Year 1, the research focus is on data compilation and the remainder of the year the emphasis is on the tectonic and depositional histories of the basin. No major problems have been encountered to date, and the project is on schedule. The principal objectives of the project are to develop through basin analysis and modeling the concept that petroleum systems acting in a basin can be identified through basin modeling and to demonstrate that the information and analysis resulting from characterizing and modeling of these petroleum systems in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin can be used in providing a more reliable and advanced approach for targeting stratigraphic traps and specific reservoir facies within a geologic system and in providing a refined assessment of undiscovered and underdeveloped reservoirs and associated oil and gas resources
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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