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The successful experience of IGCP636 project "unifying international research forces to unlock and strengthen geothermal exploitation of the Americas and Europe"
No full textGeothermal fluids are extracted through deep wells drilled in a geological reservoir, which can be represented by highly heterogeneous volcanic complex, sedimentary basins or deep basement rocks. The main objective of this project was to propose suitable methodologies and techniques for the characterization and modeling of fractured geothermal reservoirs, to ensure their sustainable exploitation and, therefore, ensure acceptation of this kind of energy by local communities. This goal was achieved with experiences from the volcanic complex of the Nevado del Ruiz (Colombia), the St. Lawrence Lowlands sedimentary basin (Québec, Canada), the Carboniferous limestone reservoir in the area of Mons (Belgium), the Soultz-Sous-Forêts power plant and the Ploemeur fractured rock hydrogeological experimental site (France), and various areas of interest for geothermal exploration in Chile. The work conducted provided new insights into the construction of conceptual and numerical models for geothermal reservoirs and allowed the creation of a solid research network between Europe and Americas, fostering participation in geosciences of young researchers, students, and women. © 2019 International Union of Geological Sciences. All rights reserved
Reclamation of Real Urban Wastewater Using Solar Advanced Oxidation Processes: An Assessment of Microbial Pathogens and 74 Organic Microcontaminants Uptake in Lettuce and Radish
No full textIn this study, disinfection of urban wastewater (UWW) with two solar processes (H2O2 -20 mg/L and photo-Fenton 10 mg/L-Fe2+/20 mg/L-H2O2 at natural water pH) at pilot scale using a 60 L compound parabolic collector reactor for irrigation of two raw-eaten vegetables (lettuce and radish) has been investigated. Several microbial targets (total coliforms, Escherichia coli, Salmonella spp., and Enterococcus spp.) naturally occurring in UWW and 74 organic microcontaminants (OMCs) were monitored. Disinfection results showed no significant differences between both processes, showing the following inactivation resistance order: Salmonella spp. < E. coli < total coliforms < Enterococcus spp. Reductions of target microorganisms to concentrations below the limit of detection (LOD) was achieved in all cases with cumulative solar UV energy per volume (QUV) ranged from 12 to 40 kJ/L (90 min to 5 h). Solar photo-Fenton showed a reduction of 66% of OMCs and solar/H2O2 of 56% in 5 h treatment. Irrigation of radish and lettuce with solar treated effluents, secondary effluents, and mineral water was performed for 6 and 16 weeks, respectively. The presence of bacteria was monitored in surfaces and uptake of leaves, fruit, and also in soil. The bacterial concentrations detected were below the LOD in the 81.2% (lettuce) and the 87.5% (radish) of the total number of samples evaluated. Moreover, uptake of OMCs was reduced above 70% in crops irrigated with solar treated effluents in comparison with secondary effluents of UWW. © 2019 American Chemical Society
Investigation and evidence of context as elements of criminal policy for the prosecution of the organized crime [La investigación y la prueba de contexto como elementos de política criminal para la persecución del crimen organizado]
No full textThe problem addressed by the article is directly related to the reflection about what is the incidence of research and context evidence as elements of criminal policy to prosecute the organized crime. We drew as first objective to make a reflective approach to the concepts of organized crime, context investigation, context evidence and criminal policy, to then develop as a second objective, its correlation from its implementation in the Inter - American Court of Human Rights and, in the Colombian case, from the context investigation modality and its derived proof. As a third objective, we sought to establish the viability from the legal and constitutional scope and with a criminal policy approach to the application of this methodology and context evidence for the prosecution of the organized crime as State's response strategy. The research approach is qualitative, which contains exploratory, descriptive, analytic and propounding research. As main result is the need for the criminal policy of the Colombian State to consolidate the application of the context investigation and, in particular, to define the way in which its products will be incorporated into the body of evidence, that is, if the results obtained in the construction of research contexts can be treated as an autonomous means of evidence with characterization and designation of context evidence. © 2020 Policia Nacional de Colombia. All rights reserved
Speeches and journeys in the corporeality of time-space [Discursos y recorridos en la corporalidad del tiempo-espacio]
No full text"The philosophy of Kant reveals, as he expressed it, a ""awakening of the Dogmatic Dream"", which is based on a copernicanic twist in Western philosophy. This article displays some reflections on this philosophical turn that can be understood in the link between body, time-space and language, where the poetic formulas: the time is out of its hinges, I am another and the deepest of the human is the skin, allow To open a comprehensive panorama of the problem of reason, understanding and sensibility of Kantian transcendental aesthetics. Therefore, the Copernicanic Giro advocated by Kant is guided by his premise according to which ""we only know of things what we ourselves put in them"" (Critique of Pure Reason), deriving in the problem on the conditions of possibility of knowledge Expressed in the relationship between body, time-space and language. From this last point of view, there is an analysis of the schematism Kantian and the Diagramatismo Foucault in what could be thought of as what beats in the corporeality of an inhabiting the world in what we project of ourselves in the margins of the Language. © 2019 Pontificia Universidade Catolica do Parana.
Thin slender concrete rectangular walls in moderate seismic regions with a single reinforcement layer
No full textSome Latin-American countries, including Colombia, Peru, Panamá and the Dominican Republic, have adopted an industrialized system for the construction of buildings using thin slender reinforced concrete walls. The main advantage of this system is that it can increase the construction speed and reduce the use of nonstructural walls, as all architectonical spaces are defined by the structural walls. Additionally, designers tend to use thin structural walls with low steel reinforcement ratios, which is reflected in a reduction of the construction cost. The typical wall section for 6 to 10-story buildings is characterized by a thickness of around 100 mm and a single layer of welded wire mesh acting as longitudinal and transverse reinforcement. Additional reinforcing bars may be placed at the wall edges to increase moment capacity, but in most cases, there are no confined boundary elements along the edges. Despite the system's popularity, experimental data for these types of walls is still scarse. In addition to this, structural walls of low thickness and high aspect ratio with unconfined or poorly confined boundary elements have shown structural deficiencies in the 2010 Central Valley Chile earthquake. In this paper, existing and new experimental data from representative thin slender walls, used in moderate seismic regions, was analyzed to evaluate the structural system under lateral loads. Two unconfined reinforced concrete walls with typical section detailing were tested. Additionally, these tests were complemented with an experimental database of 28 rectangular wall units of thickness less than 100 mm, as reported in the literature. This data was used to analyze the behavior of rectangular thin slender walls in terms of axial load ratio, boundary elements conditions, plastic hinge length, and maximum drift capacity. The experimental data shows a significant reduction in drift capacity as axial load, clear interstory height to wall thickness ratio, or wall length increases. It is also evident that plasticity is concentrated at the base of the walls, mainly due to the low vertical reinforcement ratios. Finally, a capacity vs. demand stochastic analysis was carried out to evaluate the performance of buildings up to 10 stories in a moderate seismic zone. These analyses show that for moderate seismic regions the probability of reaching a severe damage limit state is low for buildings configured with rectangular walls having a single layer of reinforcement. © 2019 Elsevier Lt
Prospective tools applied to a business valuation model of free cash flow discounted [Herramientas de prospectiva aplicadas a un modelo de valoración de empresas mediante el método de flujo de caja libre descontado]
No full textThe present project intends to establish an activity for the implementation of prospective tools in a business valuation model through the Free Cash Flow (FCL) discounted at the weighted average cost of capital (WACC). It is a company dedicated to the injection of aluminum and they are incorporated into the main tools of the company in the model, constructing valuation scenarios to establish strategies of the entity's management to avoid the materialization of the negative scenarios. © 2019. revistaESPACIOS. com
Design and Construction of a Muon Detector Prototype for Study the Galeras Volcano Internal Structure
No full textMuon tomography is a technique based on the observation of the absorption of muons in matter, as the ordinary radiography does using X-rays. The interaction of cosmic rays with the atmosphere produce Extensive Air Showers, which provide an abundant source of muons. These particles can be used for multiple applications on muon tomography, in particular, to study the internal structure of different volcanoes edifices. It is necessary in any muon tomography experiment a particle detector that has the capability to be sensitive to muon interactions. Here we report a brief description of the first steps towards a complete design of a prototype particle detector to perform muon tomography in harsh conditions encountered in the surroundings of the Galeras Volcano. The mechanical design and fabrication processes of the supporting structure of the muon detector prototype, and first steps towards a future detector simulations on GEANT4 are described in this work. © Published under licence by IOP Publishing Ltd
Toward User-Independent Emotion Recognition Using Physiological Signals
No full textMany techniques have been developed to improve the flexibility and the fit of detection models beyond user-dependent models, yet detection tasks continue to be complex and challenging. For emotion, which is known to be highly user-dependent, improvements to the emotion learning algorithm can greatly boost predictive power. Our aim is to improve the accuracy rate of the classifier using peripheral physiological signals. Here, we present a hybrid sensor fusion approach based on a stacking model that allows for data from multiple sensors and emotion models to be jointly embedded within a user-independent model. WMD-DTW, which is a weighted multi-dimensional DTW, and the k-nearest neighbor's algorithm k-NN are used to classify the emotions as a base model. The ensemble methods were used to learn a high-level classifier on top of the two base models. We applied a meta-learning approach to the data set and showed that the ensemble approach outperforms any individual method. We also compared the results using two data sets. Our proposed system achieved an overall accuracies of 65.6% for all users for the E4-data set and 94.0% and 93.6% for recognizing valence and arousal emotions, respectively, using the MAHNOB data set. © 2001-2012 IEEE
Application of the hodrick-prescott model for the price forecast of electricity in Colombia [Aplicación del modelo de hodrick-prescott para el pronóstico del precio de la electricidad en Colombia]
No full textThe Colombian electricity market aims to offer a continuous and reliable service. However, the specific characteristics associated with its high dependence on hydroelectric generation, the technical limitations that allow its storage and the passive behavior of demand jeopardize the fulfillment of this objective. Uncertainty about future results has a significant impact on investment prospects, which consequently restricts the diversification of the energy matrix. In this context, among the mechanisms considered for the valuation of new projects and regulatory reforms, the interest to study the short and long-term behavior of the price of electricity stands out. The tool proposed in this paper develops an algorithm based on the Hodrick and Prescott filter for the Colombian market, which allows identifying the behavior of the cycle and the price trend, contributing to the decision making in the sector. © 2019, Associacao Iberica de Sistemas e Tecnologias de Informacao. All rights reserved
Analyzing the impact of the digital divide on e-commerce in Colombia
No full textThe aim of this study is to examine whether the digital divide has a moderating effect on the technological factors that affect the adoption of electronic commerce. This study propose an exploratory empirical model that integrates the basic variables of e-commerce adoption through the use of the technology adoption model (TAM), making an extension with the facilitating conditions and the digital divide as a moderating variable. A digital survey was randomly distributed in Colombia, reaching a final sample of 745 electronic buyers. The explanatory result validates that the perception of the digital divide negatively moderates the influence of the variables related to internet technology on the use of e-commerce. This is one of the first studies that analyzes the effect of the digital divide on the adoption of e-commerce. © 2019 International Business Information Management Association (IBIMA)