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This paper evaluates the behavior of non-structural masonry built with horizontal hollow clay bricks. The aims of the study are to reduce the structural vulnerability of houses built with this type of bricks in seismic zones of Latin America, especially Colombia and Ecuador. The tested specimens were 50 centimeters wide, approximately 10 centimeters thick and 1 meter high. The retrofitting methods consisted of two types of reinforcement: the first one with a 3:1 sand:cement ratio. (S:C) mortar overlay with 2.5 centimeters thick for overlay the welded wire mesh (WWM) (ϕ4mm/15cm) adhered to the masonry with plastic anchors on each face of the wall. The second one with the use of mortar overlay reinforced with steel fibers (SF20) using a dosage of 20 kg/m3, with an average thickness of 2.5 centimeters and a 3:1 S:C ratio. The experimental program included the testing of 13 axial compression specimens, 4 prisms for compression with WWM reinforcement, 4 prisms for compression with SF20 reinforcement, 4 with plain mortar overlay and 1 control masonry without any type of reinforcement, only with hollow bricks. Each type of reinforcement was assessed using a monotonic quasi-static axial compression test and 3 quasi-static cyclic tests. The results showed that SF20 reinforcement increases the compressive strength, controls crack growth, but the failure mode is fragile. On the other hand, the WWM reinforcement shows a lower compressive strength, but a less fragile failure mode since the more cracks are visualized and their size increases as the load increases in the test. This is also evident in the load-deformation curves. The WWM reinforcement does contribute to life safety, by holding the collapsed clay block fragments between the mortar diaphragms. In addition, it was observed in the experimental tests that the resistance can be increased by ensuring a continuous anchorage that holds the WWM on both faces of the horizontally drilled bricks. Finally, as a conclusion, the increase of resistance by SF20 reinforcement generates stiffer prisms for compression, but it would not guarantee life protection in case of cracking or collapse of masonry walls; on the other hand, WWM does allow greater deformations, despite not having a similar resistance as the walls reinforced by SF20. [ABSTRACT FROM AUTHOR]

This paper evaluates the behavior of non-structural masonry built with horizontal hollow clay bricks. The aims of the study are to reduce the structural vulnerability of houses built with this type of bricks in seismic zones of Latin America, especially Colombia and Ecuador. The tested specimens were 50 centimeters wide, approximately 10 centimeters thick and 1 meter high. The retrofitting methods consisted of two types of reinforcement: the first one with a 3:1 sand:cement ratio. (S:C) mortar overlay with 2.5 centimeters thick for overlay the welded wire mesh (WWM) (ϕ4mm/15cm) adhered to the masonry with plastic anchors on each face of the wall. The second one with the use of mortar overlay reinforced with steel fibers (SF20) using a dosage of 20 kg/m3, with an average thickness of 2.5 centimeters and a 3:1 S:C ratio. The experimental program included the testing of 13 axial compression specimens, 4 prisms for compression with WWM reinforcement, 4 prisms for compression with SF20 reinforcement, 4 with plain mortar overlay and 1 control masonry without any type of reinforcement, only with hollow bricks. Each type of reinforcement was assessed using a monotonic quasi-static axial compression test and 3 quasi-static cyclic tests. The results showed that SF20 reinforcement increases the compressive strength, controls crack growth, but the failure mode is fragile. On the other hand, the WWM reinforcement shows a lower compressive strength, but a less fragile failure mode since the more cracks are visualized and their size increases as the load increases in the test. This is also evident in the load-deformation curves. The WWM reinforcement does contribute to life safety, by holding the collapsed clay block fragments between the mortar diaphragms. In addition, it was observed in the experimental tests that the resistance can be increased by ensuring a continuous anchorage that holds the WWM on both faces of the horizontally drilled bricks. Finally, as a conclusion, the increase of resistance by SF20 reinforcement generates stiffer prisms for compression, but it would not guarantee life protection in case of cracking or collapse of masonry walls; on the other hand, WWM does allow greater deformations, despite not having a similar resistance as the walls reinforced by SF20. [ABSTRACT FROM AUTHOR]

New requirements for a better sustainable energy policy around the world is easy to observe, many projects in sustainable energy are developed wherein the academia works together the authorities and commercial firms such as electrical grid utilities. In distribution transformers one of the suggested solutions is to replace mineral oils used as dielectric and coolant for natural ester fluids, they provide improved technical properties making them a safe substitute of mineral oil. Natural esters are based on clean technology in order to guarantee requirements from utilities. The main goal of the present paper is to present a technical-economic analysis obtained from five years of applications of oil-immersed transformers using natural ester fluids in Colombia. The methodology considers forty-four oil-immersed distribution Transformers, a half use mineral oil and the other side use natural ester, operating under the same load regime. Results evidenced the feasibility of implementing this technology because the costs are very similar and the reduction of risks and environmental impact is considerable. [ABSTRACT FROM AUTHOR]

This article presents a predictive model to determine possible obstructions in the sewerage system of the Valle de Aburrá metropolitan area in Colombia. This city has special characteristics for being located in a valley surrounded by high mountains, susceptible to rainfall almost all year round and with a population of over 4 million inhabitants. To achieve this, we apply the CRISP-DM methodology. Initially, the way how the system determines the obstructions through preventive and corrective maintenance was identified. Subsequently, the data provided by the main assets that make up the system, especially the spillways, were understood; then, the dynamic and exogenous variables that could influence the occurrence of obstructions were selected. A case study with a dataset of 3980 records with information between the years 2018 - 2021, facilitated the application of feature selection techniques to analyze the most influential variables, and the predictive model was developed to identify possible obstructions in the system. We use algorithms such as neural networks, decision trees, random forests, logistic regression, and support vector machines. The results of the neural networks yielded an accuracy of 84% that was calculated with the cross-validation method and an F1 Score of 70%. In the evaluation, the model showed that it was determined by the variables number of previous obstructions, density of afferent clients, previous maintenance, and the average rainfall of the last days. These results expand the decision-making capacity to define preventive maintenance and reduce corrective maintenance in the spillways that make up the sewerage system. Finally, it is concluded that the model can correctly predict the possible obstructions, however, it is necessary to deploy it in the complete system so that the prediction increases its level of accuracy. [ABSTRACT FROM AUTHOR]

Anthropogenic activities and climate change have caused environmental alterations in marine ecosystems, inducing stress conditions that diminish coral regeneration capacity and increase their susceptibility to bleaching and mortality. In order to determine the environmental factors associated with thermal stress events during the last 16 years in the coral reefs of Isla Tesoro – Colombia, remote sensor and reanalysis data mining of available information was performed. The results of a Principal Component Analysis (PCA) showed that not only the sea-surface temperature is related to coral stress, but also variables such as chlorophyll-a, photosynthetic radiation, pH, and sediments transported. These results, together with those of previous studies in this area, demonstrated that remote sensing technologies could facilitate the study of coral ecosystems, simplifying data collection in zones where access is limited. Hence, this document presents a database with historical information related to heat stress events and environmental variables for the coral nursery area on Tesoro Island in Los Corales del Rosario and San Bernardo National Natural Park, belonging to the Caribbean Territorial Directorate of National Natural Parks of Colombia [ABSTRACT FROM AUTHOR]

Cladosporium species are the most common fungal component of air, it is cosmopolitan and found on all kinds of plants, soil, food, and organic substrate, this genus belongs to dematiaceous fungi which represent a large and varied group of fungi. Cladosporium colombiae first isolate from Cortaderia leaves collected in Colombia, and in this study, Cladosporium colombiae was isolated from air in Basrah, Iraq, and depending on its morphology and molecular analysis, it was identified. [ABSTRACT FROM AUTHOR]

Architecture for transition is a proposal of theoretical and methodological approach that takes up approaches from the South epistemologies and critical design studies. Therefore, a conceptual debate on this perspective has the purpose of contextualizing and localizing the analysis of two communitarian small infrastructure projects generated within the framework of the peace-building process in Colombia. The evaluation of these projects implemented in the rural area of San José del Guaviare from the perspective of architecture for transition evidences a technical logic that is decontextualized, delocalized and dysfunctional in the conception and execution of the architectural design. This leads to the conclusion that the approach proposed should be considered to achieve architectural projects that adapt to the territorial conditions, respond to the inhabitants needs, strengthen community ties, and contribute to the construction of peace. [ABSTRACT FROM AUTHOR]

Examines women progress in academia work in Colombia. Government promotion of scientific research; Group directors by gender and research areas in 2000; Highest average educational level of Columbian researchers.