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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
Development of a coaxial sensing and adaptive control system for stable DED-LB processing of high-strength structural steel
No full textLAUREA MAGISTRALELa tecnologia Laser-based Directed Energy Deposition (DED-LB) rappresenta una delle soluzioni più rilevanti nell’ambito della manifattura additiva, grazie a diversi vantaggi rispetto ad altre tecnologie. Tra questi, si evidenziano l’elevata flessibilità, derivante dall’impiego di robot, che consente la realizzazione di geometrie complesse senza l’utilizzo di stampi, e la capacità di depositare grandi volumi di materiale. Tali caratteristiche rendono questa tecnologia particolarmente interessante per il settore delle costruzioni, dove è frequente l’impiego di componenti di grandi dimensioni con geometrie articolate per esigenze architettoniche e strutturali. Tuttavia, la letteratura non riporta studi relativi alla stampa degli acciai comunemente utilizzati in questo settore mediante tecnologia DED-LB. Una delle limitazioni attuali risiede nell’elevata sensibilità degli acciai maggiormente impiegati, in particolare degli acciai HSLA (High-Strength Low-Alloy), ai parametri di processo.
L’obiettivo di questo lavoro di tesi è l’implementazione di un sistema di monitoraggio e di un successivo controllo closed-loop, basato sulle grandezze più significative del processo: la geometria e la temperatura della pozza fusa. A seguito di prove preliminari, sono stati identificati i parametri più idonei per mantenere stabili queste variabili durante l’intero processo di deposizione, utilizzando polvere metallica di acciaio S700. La variabile selezionata per essere monitorata e stabilizzata è la larghezza della pozza fusa, attraverso un controllo adattivo closed-loop che regola la temperatura modificando la potenza del laser entro un intervallo predefinito.
Il sistema di monitoraggio è stato realizzato tramite una telecamera NIR con sensore CMOS e un pirometro a doppia lunghezza d’onda, entrambi in configurazione coassiale. Sono stati sviluppati algoritmi per l’intero ciclo di pre-processing delle immagini, al fine di estrarre in modo affidabile le caratteristiche geometriche della pozza fusa.
Sulla base dei risultati ottenuti, sono stati realizzati cilindri cavi con altezza pari a 100 mm, la cui deposizione, in alcuni casi, è durata anche diverse ore. Al termine, sono state condotte analisi di porosità e scansioni 3D per verificare la qualità del processo. I risultati confermano il buon esito della deposizione, con miglioramenti significativi rispetto alle condizioni iniziali, in cui la potenza del laser era mantenuta fissa per massimizzare l’efficienza. Tali condizioni, tuttavia, non permettevano la realizzazione di componenti con piccolo diametro e causavano accumuli termici eccessivi in quelli di dimensioni maggiori.The Laser-based Directed Energy Deposition (DED-LB) technology is among the most significant within the field of additive manufacturing, offering several advantages over alternative techniques. Notably, it provides high flexibility through the use of robotic systems, enabling the fabrication of complex geometries without the need for molds. Furthermore, its ability to deposit large volumes of material makes it a promising candidate for the construction industry, where large-scale components with complex shapes are often required for both architectural and structural purposes. However, the literature lacks studies addressing the additive manufacturing of steels commonly used in this sector by means of DED-LB. One of the current limitations lies in the high sensitivity of commonly used structural steels, particularly High-Strength Low-Alloy (HSLA) steels, to process parameters.
The aim of this thesis is to implement a process monitoring system and a closed-loop control strategy based on key process indicators, specifically the melt pool geometry and temperature. Following preliminary tests, optimal parameters were identified to ensure process stability during prolonged deposition using S700 steel powder. The chosen process variable for stabilization was the melt pool width, controlled via an adaptive closed-loop system that maintains a constant melt pool temperature by adjusting laser power within a specified range.
Monitoring was achieved using a coaxial setup comprising a NIR camera with a CMOS sensor and a dual-wavelength pyrometer. Dedicated algorithms were developed to perform complete image pre-processing and to accurately extract the geometric features of the melt pool.
Based on the optimized parameters, hollow cylinders with a height of 100 mm were fabricated, the deposition, in certain cases, lasted several hours. Post-process evaluation included porosity analysis and 3D scanning to validate the quality of the builds. Results confirmed a successful outcome, with substantial improvements over the initial fixed-power configuration, which, although efficient, did not support the production of small-diameter components and led to excessive heat accumulation in larger ones
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
Dispelling 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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