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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
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
Effects of hypergravity on manual forces and displacements: causes and practical implications
Get PDFZUSAMMENFASSUNG
Zahlreiche Studien haben die menschliche Motorik in Phasen erhöhter Erdbeschleunigung (+Gz) untersucht und Defizite z.B. bei Folge-, Zeige- und Kraftproduktionsaufgaben gefunden. Im letzteren Fall führte +Gz zu stark überhöhten Armkräften, wenn die Probanden einen isometrischen Joystick verwendeten. Da viele Hochleistungsflugzeuge durch solche Joysticks kontrolliert werden, könnten diese überhöhten Kräfte die Flugstabilität beeinträchtigen und daher die Sicherheit der Piloten während +Gz Flugmanövern wie Loopings und Kurven gefährden. Jedoch bleiben zahlreiche Fragen in diesem Kontext unklar: Reduziert sich die Krafterhöhung in +Gz durch ein Training? Zeigt sich bei +Gz-erfahrenen Piloten die gleiche Krafterhöhung wie bei +Gz-unerfahrenen Probanden? Sind manuelle Auslenkungen mit einem regulären Joystick wie er in anderen Flugzeugmodellen genutzt wird ebenfalls durch +Gz beeinträchtigt? Hat +Gz auch einen Einfluss auf Prozesse des motorischen Lernens? Solche Fragen beziehen sich alle auf den operativen Hintergrund von Piloten, die Hochleistungsjets fliegen, und entsprechende Antworten könnten helfen, die Flugausbildung und den Arbeitsalltag solcher Piloten zu verbessern.
Neben diesen anwendungsorientierten Fragen ist eine andere, grundlegende Frage auffallend: Warum produzieren Probanden erhöhte isometrische Kräfte in +Gz? Entsprechend der Literatur sind einige potentielle Gründe wie mechanische Aspekte, gestörtes Sehvermögen oder propriozeptive Defizite nicht in der Lage diesen Effekt zu erklären, wohingegen andere Aspekte, wie kognitive Belastung, körperliche Aktivität, vestibulo-spinale Aktivität oder psycho-physiologischer Stress tatsächlich die beobachtete Krafterhöhung in +Gz erklären könnten. Allerdings fehlen nützliche wissenschaftliche Daten, die diese letzten Theorien unterstützen würden.
Daher beinhaltet diese Promotion die Untersuchung sowohl von Fragen zur Motorik in Bezug auf fliegerische Tätigkeiten, als auch von möglichen Gründen für die +Gz-bedingte Krafterhöhung, um so das aktuelle Wissen in anwendungs- und grundlagenorientierten wissenschaftlichen Themen zur Motorik in +Gz zu erweitern.
Hinsichtlich der wissenschaftlichen Fragestellungen bezogen auf fliegerische Tätigkeiten konnten wir zeigen, dass die beobachtete Erhöhung isometrischer Kräfte in +Gz partiell durch ein anhaltendes Training in +Gz ausgeglichen werden konnte, wohingegen ein gleichwertiges Training bei normaler Erdbeschleunigung entsprechend eines Simulatortrainings auf der Erde unwirksam war. Darüber hinaus konnte eine längerfristige Gewöhnung an die +Gz Umgebung nicht beobachtet werden, da professionelle Jetpiloten, die in Trainingsflügen regelmäßig +Gz ausgesetzt sind, nur eine geringfügig kleinere Verschlechterung bei der isometrischen Kraftproduktion zeigen als +Gz-unerfahrene Probanden. Ferner konnten wir zeigen, dass weder manuelle Auslenkungen eines regulären Joysticks, noch die Fähigkeit der Probanden, ihre Motorik an unbekannte Situationen anzupassen, negativ durch +Gz beeinträchtigt sind.
Die Untersuchung möglicher Gründe für die beobachtete Krafterhöhung in +Gz zeigte, dass auch eine kognitive Belastung als zugrundeliegender Mechanismus für den Kraftanstieg in +Gz unwahrscheinlich ist, da der kognitive Aufwand bei der Untersuchung mittels der Doppeltätigkeitsmethode nicht mit dem +Gz-Level variierte. Darüber hinaus konnten wir zeigen, dass körperliche Aktivität die isometrische Kraftproduktion beeinträchtigt, sich dieser Effekt aber qualitativ von der beobachteten Krafterhöhung in +Gz unterscheidet, so dass körperliche Aktivität wahrscheinlich ebenfalls nicht der Grund für die erhöhte Kraftproduktion in +Gz ist. Im Gegensatz dazu beschreibt die vorliegende Promotion Experimente zur Kraftproduktion während Phasen von linearer Vektion, welche die Vermutung unterstützen, dass eine gesteigerte vestibulo-spinale Aktivität ein Grund für die erhöhte Kraftproduktion in +Gz ist. Zusätzlich könnten auch +Gz bedingte psycho-physiologische Veränderungen ein relevanter Faktor sein, da wir zeigen konnten, dass +Gz zu einem umfassenden Anstieg in unterschiedlichen Stresshormonkonzentrationen führt, welche einhergeht mit einer Reduktion der wahrgenommenen körperlichen und mentalen Verfassung. Da manuelle Auslenkungen weder in +Gz, bei vestibulärer Stimulation noch bei körperlicher Aktivität beeinträchtigt waren, scheinen die zugrundeliegenden Mechanismen nur Kräfte, jedoch keine Bewegungen zu beeinflussen.
SUMMARY
Several scientific studies have examined human motor performance during phases of increased terrestrial gravitational acceleration (+Gz), and found deficits e.g. in tracking, pointing and force production tasks. In the latter case, +Gz provoked highly exaggerated arm forces when subjects used an isometric joystick. Since several high-performance aircraft are controlled by such sticks this force exaggeration might impair flight stability and could therefore compromise pilots’ safety during +Gz flight maneuvers as loops and turns. However, several questions in this context remain unclear: Is the observed force exaggeration in +Gz reduced by training? Do +Gz-experienced fighter pilots show the same force exaggeration like +Gz-inexperienced subjects? Are manual displacements with a regular joystick used in different aircraft affected by +Gz as well? Does +Gz have an impact on motor learning processes? Such questions all relate to the operational background of pilots flying high-performance aircraft and answers might help to improve pilots’ flight trainings and their working lives.
Besides these applied questions, another fundamental question is striking: Why do subjects produce exaggerated isometric forces in +Gz? According to literature some possible reasons like mechanical aspects, disturbed vision or proprioceptive deficits cannot explain this effect, while other aspects, like computational stress, physical activation, vestibulo-spinal activity or psycho-physiological stress might indeed explain the observed force exaggeration in +Gz. However, valuable scientific data supporting these latter theories are missing.
Therefore, in order to enhance the current knowledge of applied as well as basic research topics on motor performance in +Gz, this thesis contains the investigation of both questions on motor performance related to flight operations as well as possible causes of the +Gz-induced force exaggeration.
Pertaining to the research questions on motor performance related to flight operations we could show that the observed isometric force exaggeration in +Gz can be partly compensated by a prolonged task practice in +Gz, while an equivalent practice conducted in normal gravitational acceleration adequate to simulation training on the ground was ineffective. Furthermore, long term adaptation to the +Gz environment could not be observed, since professional jet pilots frequently exposed to +Gz during practice flights only showed a slightly smaller deficit in isometric force production than +Gz-inexperienced subjects. We could further demonstrate, that neither manual displacements with a regular joystick nor subjects’ ability to adapt their motor performance to unknown situations are affected negatively by +Gz.
The investigation of possible causes of the observed force exaggeration in +Gz showed that also computational stress seems unlikely as an underlying reason for the force increase in +Gz, since the cognitive demand investigated by the dual task approach did not vary with the +Gz-level. We could further show that physical exercise impairs isometric force production, but since this effect differed qualitatively to the observed force exaggeration in +Gz, physical activation does probably not explain this force exaggeration in +Gz, either. In contrast, the present thesis describes experiments on force production during phases of linear vection supporting the assumption that increased vestibulo-spinal activity might be a cause of the observed force exaggeration in +Gz. Additionally, +Gz-related psycho-physiological changes might also be a relevant factor, as we could demonstrate that +Gz induces a comprehensive increase in various stress hormone concentrations going along with a decrease in perceived physical and mental state. Since manual displacements were neither affected by +Gz, vestibular stimulation nor physical activity, these underlying mechanisms seem to affect only forces, but do not apply for displacements
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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