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ANÁLISIS DE FALLA DE UN TALUD EN UN SECTOR URBANO DEL MUNICIPIO DE OCAÑA, COLOMBIA
Get PDFEl barrio San Fermín se ubica en el sector sur de la ciudad de Ocaña, en una zona de ladera con una alta intervención antrópica. Esto ha potenciado que se presentan problemas de erosión y de estabilidad de taludes, que mantienen en un nivel de riesgo considerable a una parte de sus habitantes. La investigación buscó analizar las condiciones que conllevaron a la falla de un talud en una de las terrazas que conforman el barrio y establecer las condiciones de estabilidad del talud posteriores a la falla, de modo que se pueda conocer el nivel de amenaza asociado. Se realizó una detallada investigación de campo que permitió establecer el modelo geotécnico más adecuado para el análisis. Los resultados permitieron definir las condiciones en las que se presentó la falla del talud y establecer, que posterior al deslizamiento, el talud continúa en condiciones muy susceptibles a fallar nuevamente
MANEJO DE INESTABILIDAD DE TALUDES EN LA VÍA QUE COMUNICA LAS POBLACIONES DE SAMORÉ (NORTE DE SANTANDER) Y CUBARÁ (BOYACÁ); SECTOR VIAL QUE CORRESPONDE AL EJE DE COMUNICACIÓN CÚCUTA-ARAUCA, COLOMBIA
No full textEn la construcción y mantenimiento de vías, se busca que los usuarios transiten por ellas con el mayor grado de seguridad posible. En esta lógica, un aspecto que cobra relevancia es el grado de estabilidad de los taludes de la vía y es en función de este aspecto que se abordó el problema que ocasionó uno de estos en la vía que comunica las poblaciones de Samoré (Norte de Santander) y Cubará (Boyacá), sector vial que corresponde al eje de comunicación Cúcuta-Arauca. La situación que generó el talud en años anteriores tuvo que ver con el desprendimiento de bloques de roca que ocasionaban taponamientos de la vía, y generaban peligro para los usuarios y obstrucción al cauce del río Cubugón. Esto propició un alto riesgo de accidentes y afectó al comercio de la región. La ejecución de este proyecto buscó identificar los factores condicionantes y detonantes que influyeron de manera directa en la estabilidad del terreno, para que de esta forma se plantearan e implementaran las alternativas de solución a corto y largo plazo, que llevaron a disminuir el nivel de riesgo para los usuarios. Palabras clave: Factores desencadenantes; Caídos de roca; Estabilización; Pantalla anclada
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
Non-linear response of reinforced concrete wall structures
Get PDFIntroducción: Muchas edificaciones compuestas por marcos (vigas-columnas) tienen la necesidad de recurrir a muros de concreto reforzado para proporcionar una mayor rigidez lateral. El comportamiento no lineal de sistemas con muros de concreto reforzado es incierto y, por lo tanto, se requiere conocer de manera adecuada la respuesta estructural de estos ante diferentes excitaciones sísmicas por medio de criterios adecuados de modelación. Objetivo: Este estudio tiene como finalidad encontrar una metodología adecuada de modelación para muros de concreto reforzado considerando discretizaciones tipo armadura. Para validación se utiliza uno de los especímenes presentados en un informe experimental, en donde se reportan pruebas a distintos muros sometidos a cargas cíclicas de desplazamientos que caracterizan prototipos reales. Metodología: Se utiliza como modelo de calibración los resultados de ensayo del espécimen experimental No. 6, presentados en el reporte No. UBC/EERC-79/20 realizado en la universidad de California, Berkeley. El espécimen es sometido a una carga lateral cíclica reversible y cargas concentradas debido a los pisos superiores, estas cargas son utilizadas como excitación para el modelo analítico. Las características geométricas y propiedades mecánicas son tomadas del informe para la modelación analítica. Resultados: Con la metodología anterior es posible modelar cualquier muro de concreto reforzado bidimensional. Los resultados obtenidos en términos del cortante basal y desplazamiento en la azotea son comparados con los mostrados en el informe experimental. La curva de histéresis global (δ3 vs Vb) es obtenida sometiendo al modelo analítico a una carga pseudoestática reversible y considerando los parámetros no lineales de cada uno de los materiales. Conclusiones: Los resultados obtenidos con el modelo analítico discretizado en elementos armadura presentan una gran aproximación con los mostrados en el estudio experimental utilizado como comparación, por lo cual, este criterio es posible utilizarlo para modelar cualquier tipo de muro de concreto reforzado en el espacio bidimensional e incluso tridimensional.Introduction− Many buildings composed of frames (beams-columns) must resort to reinforced concrete walls to provide greater lateral stiffness. The non- linear behavior of systems with reinforced concrete walls is uncertain and, therefore, it is necessary to know adequately the structural response of these to different seismic excitations by means of suitable mod-eling criteria.Objective− This study aims to find an adequate mod-eling methodology for reinforced concrete walls consid-ering frame type discretizations. For validation, one of the specimens presented in an experimental report is used, where tests are reported to different walls sub-jected to cyclic displacement loads that characterize real prototypes.Methodology− The experimental results of experi-mental specimen No. 6, presented in the report No. UBC/EERC-79/20 conducted at the University of California, Berkeley, are used as a calibration model. The specimen is subjected to a reversible cyclic lateral load and concentrated loads due to the upper floors, these loads are also used as excitation loads for the analytical model. The geometric characteristics and mechanical properties are taken from the report for analytical modeling.Results− With the previous methodology, it is possible to model any two-dimensional reinforced concrete wall. The results obtained in terms of basal shear and dis-placement on the roof are compared with those shown in the experimental report. The global hysteresis curve (δ3 vs Vb),) is obtained by subjecting the analytical model to a reversible pseudo-static load and consider-ing the non-linear parameters of each of the materials.Conclusions− The results obtained with the ana-lytic model discretized in frame elements present a great approximation with those shown in the experi-mental study used as a comparison, therefore, this criterion can be used to model any type of reinforced concrete wall in two-dimensional space and even three-dimensional.Váquez Martínez, Alberto-5b15f494-e0d8-423c-821f-2eecd4f024e7-0Gallardo Amaya, Romel Jesus-1a59fe7c-143b-407e-a01f-0eaf953bd4c6-
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
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