<p>The <em>Araucaria araucana</em> is an endemic species from Chile and Argentina, which has a high biological, scientific and cultural value and since 2016 has shown a severe affection of leaf damage in some individuals, causing in some cases their death. The purpose of this research was to detect, from hyperspectral images, the individuals of the Araucaria species (<em>Araucaria araucana</em> (Molina and K. Koch)) and its degree of disease, by isolating its spectral signature and evaluating its physiological state through indices of vegetation and positioning techniques of the inflection point of the red edge, in a sector of the Ralco National Reserve, Biobío Region, Chile. Seven images were captured with the HYSPEX VNIR-1600 hyperspectral sensor, with 160 bands and a random sampling was carried out in the study area, where 90 samples of Araucarias were collected. In addition, from the remote sensing techniques applied, spatial data mining was used, in which Araucarias were classified without symptoms of disease and with symptoms of disease. A 55.11% overall accuracy was obtained in the classification of the image, 53.4% in the identification of healthy Araucaria and 55.96% in the identification of affected Araucaria. In relation to the evaluation of their sanitary status, the index with the best percentage of accuracy is the MSR (70.73%) and the one with the lowest value is the SAVI (35.47%). The positioning technique of the inflection point of the red edge delivered an accuracy percentage of 52.18% and an acceptable Kappa index.</p>
The present work´s objective is to analyze the operation of the theoretical discursive reasoning that is generated when engineering students solve problems of geometry in a pencil and paper environment. The results related to the different characteristics of the structuring of the discourse identified in the resolutions of four problems are presented. A classification of each characteristic was made for each student's speech and was related to the performance indicators of the theoretical discursive reasoning Keywords-Discursive reasoning, engineering, geometry, deductive step.
En la localidad de Ranguelmo, comuna de Coelemu, Región de Ñuble, existe una memoria oral y tácita asociada al pasado ferroviario del sector y una remembranza hacia las formas de construcción cotidiana y social que esta generaba. Vivencias y materialidades que se plasman en la reproducción de una memoria histórica que se traspasa entre generaciones del sector. No obstante, en la actualidad, la memoria y oralidad colectiva de Ranguelmo resiste con dificultades ante los embates del tiempo y los cambios sociales. Las vivencias y relatos de las épocas de gloria del ferrocarril se apagan, desapareciendo sin dejar registros ni testimonios que permitan heredar debi-damente las memorias de las experiencias pasadas a las nuevas generaciones, que bien perciben el importante rol del ramal de Rucapequén y su estación principal Ranguelmo en sus identidades y patrimonio local. El presente artículo busca presentar los resultados y experiencia asociada a una investigación patrimonial participativa con la comunidad de la localidad de Ranguelmo. En particular se propone identificar, socializar y poner en valor el patrimonio material e inmaterial relacionado al ramal de trenes de Ranguelmo, por medio de la conjunción de metodologías cualitativas y participativas que permiten un importante rescate de la memoria histórica y patrimonio material e inmaterial asociado al ramal, revitalizando la memoria y oralidad que vienen a reforzar la identidad de Ranguelmo.
Abstract. In an era of increasing wildfires frequency and intensity an accurate estimation of the emissions released to the atmosphere is essential to reduce their impacts. In this study, we improve the accuracy of our estimations by introducing field measurements of biomass and adapting the burning efficiency factors to different levels of burn severity computed from Sentinel-2 data. The biomass measured in the field complemented the data found in the literature. The emissions derived were compared with the emissions from the GFED product showing a good agreement, although GFED values were higher than ours, suggesting that GFED may overestimate the emissions due to their coarse resolution and the generalized factors applied to large ecosystems.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.