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Forecast of the energy price in colombia: An econometric application [Pronóstico de precio energético em colombia: Una aplicación econométrica]
No full textForecasting the price of electric energy is of the utmost importance for entrepreneurs, academics and regulators, as this market is essential for the economic development of the countries. Its forecast is a challenge, since it is a basic product that has high levels of volatility, because its behavior depends on the climate, the price of fuels and the limitations for its storage. For this reason, a method is proposed to forecast the price of electricity in the Colombian market, based on economic models; ARIMA-GARCH. Through the statistics, it was concluded that the model of mayor adjustment for the variation of the price in media is an ARMA (14.10)–GARCH (1.1), indicating that the decision makers will consider the results of the last 14 days to design your investment strategies. © 2020, Associacao Iberica de Sistemas e Tecnologias de Informacao. All rights reserved
Spacegoat, sacrificial exchange, violence and corporality [Chivo expiatorio, intercambio sacrificial, violencia y corporalidad] [Bouc émissaire, substitution sacrificielle, violence et corporalité] [Bode expiatório, troca sacrificial, violência e corporalidade]
No full textThis article develops a reflection on the relationship among between cult, celebration, and sacrificial substitution in the foundation of human time-space. For this purpose, the author resorts to D. H. Lawrence´s novel The Plumed Serpent, where a bullfight is depicted. For reading this fragment of the novel, the argument articulating the text has as an finds expository support in René Girad´s concept of the scapegoat, the concept of fetishism developed by Auguste Comte, and Michel Serres´ analysis on the of sacrificial exchange which supports the whole totality of human social practice. © 2020 Editora Mundos Sociais. All rights reserved
Case study for a mining investment project, applying real option of abandonment using binomial trees and conditional volatility model [Caso de estudio para un proyecto de inversión minera, aplicando opción real de abandono mediante árboles binomiales y modelos de volatilidad condicional]
No full textEn esta investigación se presenta un estudio para determinar la viabilidad financiera de un proyecto de inversión que consiste en la extracción de oro subterráneo. En este se analiza como insumo fundamental la volatilidad del precio del oro, estimando un modelo econométrico de volatilidad tipo GARCH. Adicionalmente, se realiza la valoración del proyecto aplicando una opción real de abandono con Arboles Binomiales. © 2018.In this research, a study is presented to determine the financial viability of an investment project that involves the extraction of underground gold. In this, the volatility of the price of gold is analyzed as a fundamental input, estimating an econometric model of GARCH volatility. Additionally, the evaluation of the project is carried out applying a real abandonment option with Binomial Trees. © 2018
Comparative Degradation of Alachlor Using Photocatalysis and Photo-Fenton
No full textA comparative study about the degradation of alachlor in aqueous solutions under different photocatalytic systems, including TiO2, TiO2/H2O2, and TiO2/Na2S2O8 heterogeneous photocatalysis, Fe2+/H2O2, Fe3+/H2O2, and UV radiation, was carried out. In this way, times for alachlor total removal and mineralization followed the order photo-Fenton < photocatalysis with persulfate < photo-Fenton-like < photocatalysis with hydrogen peroxide < photocatalysis with TiO2. Ferric chloride was used as ferric ion source under Fenton-like reactions. Oxidation with Fe2+/H2O2 was faster than treatment with Fe3+/H2O2, but under UV irradiation, degradation rates were similar, indicating that FeCl3 could be a good source of ferric ions for alachlor degradation. Reduction of the sample toxicity was much faster in the photo-Fenton process than in TiO2 process (50% mortality reduction in 180 min compared to around 400 min—Daphnia Pullex assays). In addition, evaluation of the nitrogen and chloride contained in the treated samples confirmed a 100% conversion of the N and Cl content in the pollutant molecule. Finally, some of the degradation by-products for pollutant removal using TiO2 photocatalysis were identified. © 2018, Springer Nature Switzerland AG
Registros
Full text linkCompreender as mutações do ecossistema midiático tem sido uma prática na academia, especialmente no campo das ciências sociais aplicadas. As transformações têm sido constantemente observadas e podem ser vistas em publicações de diversas formas midiáticas. Entretanto, pela liquidez desse cenário, os estudos não se esgotam e tornam-se fundamentais para que a relação sociedade e meios exista de maneira harmônica e eficaz. Mas essa preocupação não é algo de hoje. No início da década de 1970, na cidade de Nova Iorque, surgia pelas mãos de Neil Postman e Marshall McLuhan o programa de doutorado em Ecologia dos Meios, impulsionado pela preocupação em desenvolver as teorias relacionadas a essa corrente e, em seguida sustentar estudos futuros. No escopo, encontravam-se olhares direcionados à rádio, à fotografia, ao cinema, aos jornais, às revistas, aos livros, à televisão e a todos os ambientes e processos aos quais esses canais ou meios estavam relacionados. Processos que compunham uma galáxia composta por uma, ou algumas, aldeias globais. Uma aldeia onde o meio era a mensagem. Porém, nos dias atuais, os estudos sobre ecologia dos meios tornam-se ainda mais relevantes. As estruturas comunicacionais são construídas a partir de novas tramas de atores midiáticos. A potencialização dos processos comunicacionais cresceu exponencialmente. O poder midiático, por sua vez, ganhou outro status. Com isso tudo, novas linguagens comunicacionais passaram a ser adotadas pela sociedade.http://www.riaeditorial.com/index.php/registros/Compreender as mutações do ecossistema midiático tem sido uma prática na academia, especialmente no campo das ciências sociais aplicadas. As transformações têm sido constantemente observadas e podem ser vistas em publicações de diversas formas midiáticas. Entretanto, pela liquidez desse cenário, os estudos não se esgotam e tornam-se fundamentais para que a relação sociedade e meios exista de maneira harmônica e eficaz.
Mas essa preocupação não é algo de hoje. No início da década de 1970, na cidade de Nova Iorque, surgia pelas mãos de Neil Postman e Marshall McLuhan o programa de doutorado em Ecologia dos Meios, impulsionado pela preocupação em desenvolver as teorias relacionadas a essa corrente e, em seguida sustentar estudos futuros. No escopo, encontravam-se olhares direcionados à rádio, à fotografia, ao cinema, aos jornais, às revistas, aos livros, à televisão e a todos os ambientes e processos aos quais esses canais ou meios estavam relacionados. Processos que compunham uma galáxia composta por uma, ou algumas, aldeias globais. Uma aldeia onde o meio era a mensagem.
Porém, nos dias atuais, os estudos sobre ecologia dos meios tornam-se ainda mais relevantes. As estruturas comunicacionais são construídas a partir de novas tramas de atores midiáticos. A potencialização dos processos comunicacionais cresceu exponencialmente. O poder midiático, por sua vez, ganhou outro status. Com isso tudo, novas linguagens comunicacionais passaram a ser adotadas pela sociedade
Dynamic managerial capabilities, international opportunities, and international performance : evidence from an emerging economy
Full text linkThe opportunity has become a central concept in the international entrepreneurship (IE) literature, and there is now a critical mass of literature focused on entrepreneurial behaviors of pursuing opportunities across national borders. However, scholarly studies claim that research on these opportunity-related behaviors should consider an individual-level analysis to understand better how managers discover, enact, evaluate, and exploit opportunities to capture the market value and achieve international performance. The main objective of this study is to analyze from a dynamic managerial capability perspective the relationship between managerial capabilities, international opportunities, and international performance. The research used a mixed research methodology through qualitative and quantitative analysis (multiple case-study and structural equation modeling respectively) in international ventures from Colombia, a Latin American emerging economy. Overall, the main findings of the study clarify the nature and pattern of opportunity-related behaviors and the way individuals (managers) deploy specific cognition, human capital, and social capital capabilities to discover, enact, evaluate, and exploit international opportunities. Moreover, the results show that the interplay of these managerial capabilities serves as a platform to reconfigure existing capabilities, and thus obtain performance in international markets. The findings also suggest that managers' opportunity-seeking behavior becomes a dynamic managerial capability that enables them to develop more sophisticated capabilities and therefore respond to changing market conditions to get a competitive advantage. The study contributes to knowledge of IE by clarifying the interaction between entrepreneurial individual acting and international opportunities. Furthermore, the academic contributions of this thesis include the extension of Jones and Coviello's (2005) model and previous models by developing a model that describes factors influencing international opportunity-related behaviors, their processes, and respective effects. Finally, the research offers theoretical and practical contributions.Doctor en AdministraciónDoctorad
Diseño de un modelo de negocio basado en la comercialización de baterías ion litio para la Empresa URLOP SAS
Full text linkUrlop S.A.S. es una pequeña pyme fundada en el año 2015 en la ciudad de Bogotá, Colombia, con el objetivo de comercializar acumuladores eléctricos y equipos de seguridad electrónica en las ciudades de Bogotá y Medellín. Desde hace tres años la compañía no se encuentra en operación debido a sus resultados negativos originados a causa de una deficiente estructuración del negocio y poca experiencia en el mercado. El objetivo de este proyecto es diseñar un modelo de negocio para la comercialización de baterías de litio para la empresa Urlop SAS, enfocado en el sector de la movilidad eléctrica de Medellín y el Valle de Aburrá, así como en municipios cercanos, que permita la reactivación de la compañía, le brinde soluciones a las nuevas necesidades del parque automotor eléctrico e híbrido e, indirectamente, le aporte a la reducción de emisiones de dióxido de carbono, monóxido de carbono y óxidos nitrosos al medio ambiente, así como a la correcta disposición de los desechos derivados del proceso de recambio de las baterías.Magíster en Administración MBAMaestrí
El sector extractivo y los mecanismos de participación ciudadana : la consulta previa y la consulta popular en Colombia
Full text linkEl presente trabajo pretende establecer la relación que se ha establecido en Colombia entre los mecanismos de participación y el sector extractivo, explorando como estos mecanismos se han venido implantando a través de tratados internacionales, legislación nacional y el impacto que los mismos han tenido en dicho sector. Con el fin de desarrollar este análisis, se realiza una investigación de tipo cualitativa que busca responder la pregunta ¿Cómo se articulan los mecanismos de participación ciudadana y el sector extractivo en el orden jurídico colombiano?, la cual se responde desde un estudio analítico que permita revisar en profundidad lo que la normatividad y los documentos académicos digan al respecto. Encontrando, por lo tanto, que los mecanismos de participación se han ido implementando a lo largo de los últimos años con el fin de asegurar la participación ciudadana en el desarrollo económico de su región, a pesar de que en muchas ocasiones no se realiza dicho proceso para determinar la viabilidad de realizar una explotación minero-energética y su afectación a los territorios aledaños.Magíster en Derechos Humanos y Derecho Internacional HumanitarioMaestrí
Tourist trails in peripheral city areas
No full textIn this article, we examine the problem of tourist trails located in city peripheries, using a case study of trails in the Cerro Pan de Azúcar, a geographic area in the central-eastern suburbs of Medellín, Colombia. To this end, extant literature was examined regarding issues such as urban development, city peripheries, popular neighbourhoods, tourist trails and the territory. Additionally, with an exploratory methodology and fieldwork based on visual prospecting, participatory work with local communities and surveying topographic profiles, the study area was contextualised and technical data sheets were developed, which provide data on the trails studied. The findings are translated into technical information that contribute to promoting and preserving the environment to the extent that recognising the trails and promoting local inhabitants make these paths a viable alternative for social, environmental and economic development. Conclude that it is necessary to draw attention to the issue of peripheral trail preservation on any municipal administration's agenda, as otherwise, they inevitably tend to disappear. © 2019 AJHTL
A new sustainable geotechnical reinforcement system from old tires: Experimental evaluation by pullout tests
No full textThe tires used constitute an environmental problem that remains unsolved. It is observed that the automotive fleet and therefore the generation of tires increases year after year, so the recovery and reuse processes are insufficient. For several years, the reuse of tires as materials in the construction has been considered, and several techniques have been developed for the construction of retaining walls and road reinforcement. However, to date, their use remains sporadic. This article presents the theoretical and experimental evaluation of a new geotechnical reinforcement system from used tires. This system, suitable for the construction of containment structures and the reinforcement of roads, is characterized by the conformation of cells that do not require other elements apart from the tires and the filling material. A mathematical model was developed to describe the behavior of the system and pullout tests were carried out for validation. The tests were performed with different tire and compacted granular material with different energies. The results allow validating the theoretical model by showing an increase in pullout resistance with the density and number of tires in the arrangement. It is observed that the coincidence between the model and the tests improves as the stiffness of the soil increases, being the degree of compaction fundamental for the operation. © 2020 by the authors