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Caracterización térmica y del estilo eruptivo de columnas eruptivas del volcán tungurahua en el período 2002-2016
Get PDFEl Volcán Tungurahua (5023 m snm) es un estratovolcán activo de composición andesítica de la Cordillera Real del Ecuador y es vigilado por el Instituto Geofísico de la Escuela Politécnica Nacional (IG-EPN). El último periodo eruptivo ocurrió entre 1999 y 2016, con episodios de actividad estromboliana, vulcaniana y subpliniana; generando columnas eruptivas de diferente estilo.
El Tungurahua es vigilado con diferentes técnicas incluyendo la térmica. En el presente trabajo se analiza la base de datos de imágenes térmicas terrestres del IG-EPN de este volcán entre 2002 y 2016, de dos cámaras térmicas infrarrojas de diferente resolución, con el fin de brindar una caracterización térmica y del estilo eruptivo de las columnas eruptivas de este volcán; a través de un análisis cualitativo y cuantitativo.
Las imágenes térmicas son clasificadas en base a su calidad, entre muy buena, buena y mala. Las imágenes de muy buena y buena calidad son analizadas y se estima las temperaturas máximas aparentes (TMA) de zonas sobre la cumbre y bajo la cumbre. Con el objetivo de determinar en qué medida las TMA del volcán Tungurahua pudieron verse afectadas por la resolución de las diferentes cámaras, se realiza una correlación de Pearson y regresiones lineales de datos de temperatura de la actividad actual del volcán El Reventador. Se toma en cuenta las cámaras utilizadas en Tungurahua y se incluye una tercera de mejor resolución. La correlación realizada entre las temperaturas de las cámaras de menor y mayor resolución se estima coeficientes de determinación de 0,94 y 0.98, indicando la validez del método. Mediante la aplicación de estas correlaciones en las medidas de temperatura del volcán Tungurahua se puede estimar temperaturas más aproximadas a la realidad.
Por otro lado, la caracterización del estilo eruptivo de las columnas se basa en la estimación de sus alturas, duración, velocidad de ascenso y de las partículas balísticas. De allí se puede caracterizar las columnas seleccionadas con estilo vulcaniano y estromboliano, este último con dos subtipos: tipo 2a y tipo 2b.
Este estudio refleja que el análisis cualitativo y cuantitativo multitemporal de imágenes térmicas de un volcán en erupción puede brindar información útil para caracterizar y realizar comparaciones entre diferentes niveles de actividad a través del tiempo.Tungurahua Volcano (5023 m asl) is an active andesitic stratovolcano in Ecuador's Cordillera Real and is monitored by the Geophysical Institute of the National Polytechnic School (IG-EPN). The last eruptive period occurred between 1999 and 2016, with episodes of Strombolian, Vulcanian, and sub-Plinian activity, generating eruptive columns of different styles.
Tungurahua is monitored using different techniques, including thermal imaging. In this work, the IG-EPN's ground-based thermal image database of this volcano from 2002 to 2016 is analyzed, using two infrared thermal cameras of different resolutions. This study provided a thermal and eruptive style characterization of the volcano's eruptive columns through qualitative and quantitative analysis.
The thermal images are classified based on their quality, ranging from very good, good, and bad. Very good and good quality images are analyzed, and the maximum apparent temperatures (MAT) of the above- and below-summit areas are estimated. To determine the extent to which the MAT´s of Tungurahua volcano could be affected by the resolution of the different cameras, a Pearson correlation and linear regression analysis of temperature data from the current activity of El Reventador volcano were performed. Two cameras used at Tungurahua were taken into account, and a third camera with higher resolution is included. The correlation between the temperatures of the lower- and higher-resolution cameras yielded coefficients of determination of 0.94 and 0.98, indicating the validity of the method. By applying these correlations to the temperature measurements at Tungurahua volcano, temperatures more accurately approximated reality are estimated.
The characterization of the eruptive style of the columns is based on estimates of their heights, duration, ascent velocity, and ballistic particle. From this, the selected columns are characterized as having a Vulcanian and Strombolian style, the latter with two subtypes: type 2a and type 2b.
This study demonstrates that the multitemporal qualitative and quantitative analysis of thermal images of an erupting volcano can provide useful information for characterizing and comparing different levels of activity over time
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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