1,720,953 research outputs found
Design of beam-forming networks using coherently radiating periodic structures
No full textLa comunicación a distancia ha existido desde hace mucho tiempo, en la actualidad, se utiliza tecnología para transmitir información desde dos puntos. Las comunicaciones inalámbricas no requieren de un medio física para la propagación de la información, por lo que se utilizan ondas electromagnéticas. Por lo tanto, los únicos dispositivos físicos que están presentes son los emisores y receptores de señales, como por ejemplo las antenas. El uso de arreglos de antenas presenta más ventajas con respecto al uso de una sola antena, es por eso que son empleados en gran cantidad para satisfacer las demandas en telecomunicaciones. La generación de lóbulos estrechos y el escaneo del haz principal son algunas de las ventajas del uso de arreglos de antenas. Además de la posibilidad de generar patrones de radiación con ciertas características predefinidas mediante el diseño de la red de conformación de haz. La red de conformación de haz provee las excitaciones de amplitud y fase a los elementos de antena mediante el uso de dispositivos activos como amplificadores y atenuadores. Sin embargo al requerir arreglos de antenas con mayor tamaño es necesario el aumento de dispositivos activos lo que se traduce en aumentar los costos de fabricación. El diseño de la red de conformación de haz para arreglos de antenas lineales propuesto en esta tesis aprovecha la propiedad de interpolación de la fase de una red CORPS de una capa permitiendo la reducción del número de dispositivos activos usados y la capacidad de escaneo del haz de radiación con un nivel bajo de lóbulos laterales. Finalmente, se realizan simulaciones electromagnéticas en el software CST Microwave Studio para la validación de los resultados obtenidos.Distance communication has been around for a long time. Today technology is used to transmit information from two points. Wireless communications do not require physical medium for the propagation of information. So electromagnetic waves are used, which do not require a medium to propagate. Therefore, the only physical devices that are present are the transmitters and the receivers of signals, such as antennas. The use of antenna arrays has more advantages over a single antenna. That is the reason why they are used in large numbers to accomplish the main demands of telecommunications. The generation of narrow lobes and scanning capabilities of the main beam are some of the advantages of using antenna arrays. In addition to the possibility of generating radiation patterns with predefined characteristics through the design of the beam-forming network. The beam-forming network provides the amplitude and phase excitations to the antenna elements through the use of active devices such as amplifiers and attenuators. However, it is necessary to increase the number of active components by requiring larger antenna arrays, which translates into increasing manufacturing costs. The design of the beam-forming network for linear arrays proposed in this thesis takes advantage of the phase interpolation property of a one-layer CORPS network. This is in order to provide a reduction in the number of phase shifters used while maintaining the scanning capability and low side lobe level. Finally, electromagnetic simulations based in CST Microwave Studio are performed to validate the results obtained
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
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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