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- PublicaciónAcceso abiertoA database of common vampire bat reports(2022-02-16) Van de Vuurst, Paige; Diaz, M. Monica; Rodriguez-San Pedro, Annia; Allendes, Juan Luis; Brown, Natalie; Gutierrez, Juan David; Zarza, Heliot; De Oliveira, Stefan V.; Cardenas-Canales, Elsa; Barquez, Ruben M.; Escobar, Luis E.The common vampire bat (Desmodus rotundus) is a sanguivorous (i.e., blood-eating) bat species distributed in the Americas from northern Mexico southwards to central Chile and Argentina. Desmodus rotundus is one of only three mammal species known to feed exclusively on blood, mainly from domestic mammals, although large wildlife and occasionally humans can also serve as a food source. Blood feeding makes D. rotundus an effective transmissor of pathogens to its prey. Consequently, this species is a common target of culling efforts by various individuals and organizations. Nevertheless, little is known about the historical distribution of D. rotundus. Detailed occurrence data are critical for the accurate assessment of past and current distributions of D. rotundus as part of ecological, biogeographical, and epidemiological research. This article presents a dataset of D. rotundus historical occurrence reports, including >39,000 locality reports across the Americas to facilitate the development of spatiotemporal studies of the species. Data are available at https://doi.org/10.6084/m9.figshare.15025296
- PublicaciónAcceso abiertoActividades de innovación en servicios en las pequeñas y medianas empresas comerciales del sector textil de Valledupar, Colombia(2016) Pertuz Peralta, Vanessa Paola; Boscan Romero, Neida Coromoto; Straccia Martínez, Daysi Coromoto; Pérez Orozco, Adith BismarckThe article aims to describe the service´s activities of innovation in small and medium enterprises (PYMES) in the textile sector in Valledupar, Colombia. The activities include the knowledge's acquisition and machines, preparations for innovation, market research and training processes. This research is descriptive, a field research, non-experimental and transactional. The CEO answers a Likert questionnaire. The results indicate the predominant activity is the acquisition of machinery. In contrast, there is a low acquisition of knowledge from abroad and preparation to innovate. The conclusions are the suggestion of innovation's plans; market's analyses and diversify sources of knowledge.
- PublicaciónAcceso abiertoAG-CASU : An algorithm to generate irrigation parameters and crop management strategies for the aquacrop model(2019-05) Pertuz Peralta, Vanessa Paola; Pérez Orozco, Adith Bismarck; Maestre Pérez, Jesus David; Ortiz Iglesias, María Isabel; González Guerrero, EnriqueThis paper presents an algorithm to generate the irrigation policies and crop management configuration files for the agroclimatic risk model AquaCrop. The software determines the parameters to be modified by a stochastic method. The AG-CASU algorithm takes account of the limits determined for each variable. The algorithm can be configured to determine the number of scenarios, the number of simulations, the feasibility of each of the parameters, the initial seed file and the compliance with the AquaCrop agroclimatic risk model. In general, the agroclimatic risk models use data and information referring to climate, soil composition, temperature, rainfall, availability of water resources and characteristics of the crops to estimate the productivity of a given crop. The genetic algorithm for calculating fitnness is connected to the AquaCrop simulator, which, given a set of parameters that represent an irrigation policy, generates an estimate of biomass productivity. The algorithm was validated through a case study in special coffee crops of the Sierra Nevada de Santa Marta, Colombia. The proposed algorithm automatically obtains the files corresponding to irrigation policies and cultivation strategies of the AquaCrop model, with coverage of the domain of the variables and with compliance to the AquaCrop software.
- PublicaciónAcceso abiertoAn analysis of the types of innovation capabilities in medium-sized enterprises(2019-07-30) Pertuz-Peralta, Vanessa Paola; Perez-Orozco, Adith Bismarck
- PublicaciónAcceso abiertoAnalysis of operating costs for producing biodiesel from palm oil at pilot-scale in Colombia(2015-01) Acevedo-Páez, Juan Camilo; Hernández, Jorge A.; Valdés Rentería, Carlos Francisco; Khanal, Samir KumarThe present study aims to evaluate the operating costs of biodiesel production using palm oil in a pilot-scale plant with a capacity of 20,000 L/day (850 L/batch). The production plant uses crude palm oil as a feedstock, and methanol in a molar ratio of 1:10. The process incorporated acid esterification, basic transesterification, and dry washing with absorbent powder. Production costs considered in the analysis were feedstock, supplies, labor, electricity, quality and maintenance; amounting to $3.75/gal ($0.99/L) for 2013. Feedstocks required for biodiesel production were among the highest costs, namely 72.6% of total production cost. Process efficiency to convert fatty acids to biodiesel was over 99% and generated a profit of $1.08/gal (i.e., >22% of the total income). According to sensitivity analyses, it is more economically viable for biodiesel production processes to use crude palm oil as a feedstock and take advantage of the byproducts such as glycerine and fertilizers.
- PublicaciónAcceso abiertoAnalysis of the atmospheric macro-physical using spatial methods(2020-12-01) Andrades-Grassi, J. E.; Cuesta-Herrera, L.; Torres-Mantilla, H. A.; López-Hernández, J. Y.The central western area of Venezuela has an unequal distribution of precipitation. Due to its agricultural importance, is necessary to plan water accounting and this requires a evaluation of spatial and temporal variability of precipitation and an estimate of local geophysical effect from the relief. In this research we use an iterative computationally lattice approach to perform a confirmatory analysis of the variability and the spatial correlation structure in monthly precipitation stations. Spatial correlograms and pooled empirical semivariogram were applied to evaluate the most appropriate spatial weighting matrix to estimate the Moran’s I. The altitude effect over monthly rainfall was estimated through spatial regression algorithm which determine the predominant spatial process in each slice. A homogeneous spatial stochastic process with positive spatial autocorrelation is evidenced. There is a trend towards a higher frequency of spatial error and spatial auto-regressive processes between the months of June and August whilst there are not dominant process between October and December. This response is caused by the dynamics of the intertropical convergence zone, which generates a seasonal effect on precipitation. These estimations allows decision-making in modeling and will lead to an improvement for analysis and forecasting in areas strongly affected by climate change and water stress.
- PublicaciónAcceso abiertoAnalysis of the biodiesel production yield from waste frying oil(2018) Acevedo-Páez, Juan Camilo; Urbina-Suarez, N A; Acevedo, A.Z.; Becerra, L.C.; Arenas, E.This research sought to produce biodiesel from waste frying oil (WFO) from chicken grills by using chemical transesterification to evaluate quality conditions and the yield of the biodiesel obtained. For this, acid esterification and basic transesterification were applied under the following conditions: reaction temperature 60°𝐶, catalyst concentration of 1% (m/m) KOH, oil:alcohol 1: 6 𝑚𝑜𝑙𝑎𝑟 𝑟𝑎𝑡𝑖𝑜, and two reaction times (55 𝑎𝑛𝑑 70𝑚𝑖𝑛) for the transesterification. The physicochemical properties of the raw material were analyzed (i.e., density, humidity, kinematic viscosity, fatty acid profile, acidity index, peroxides, and saponification) where the WFO showed high contents of oleic acid (42.45%) and palmitic acid (33.52%), which are fundamental for biodiesel production. Chemical transesterification under the conditions of 60°𝐶, 1% KOH, and 70𝑚𝑖𝑛 obtained the best yield by presenting a high conversion percentage (96.15%) and an acid number of 1.33𝑚𝑚𝐾𝑂𝐻/𝑔, according to ASTM D6751 and EN 14214 international standards.
- PublicaciónAcceso abiertoAnálisis de la ciencia, tecnología e innovación desde la actividad de los observatorios en Colombia y Venezuela(2017-03) Pérez Orozco, Adith Bismarck; Pertuz Peralta, Vanessa Paola; Torres Moreno, Miguel EduardoEl artículo analiza la dinámica de la ciencia, tecnología e innovación (CTeI) en Colombia y Venezuela desde el rol de los observatorios de CTeI. Se revisó bibliografía de las diferentes justificaciones de la CTeI de algunos países (USA, Brasil) y documentos de los observatorios. Los resultados presentan diferencias en la naturaleza jurídica, la concepción estratégica y operativa. En Colombia el observatorio se sustenta en un grupo de investigación, y en Venezuela, es una entidad de administración de CTeI estatal.
- PublicaciónAcceso abiertoAnálisis de la estructura intelectual y la evolución de la investigación en la interacción humano-computador : Un análisis bibliométrico(2019-01) Galeano Barrera, Claudia Jazmín; Martínez Toro, M.; Rico Bautista, Dewar; Romero Riaño, E.; Guerrero, Cesar D.; Parra Valencia, J.A.Bibliometrics is the application of quantitative models and methods for the understanding of research disciplines. The main concepts that are applied within the development of this type of analysis are associated to the analysis of networks and include the links, number of links and force of link within the networks of co-occurrence, co-citation, co-authorship and bibliographic links. Under these concepts and in order to visualize the evolution of human-computer interaction (HCI), a bibliometric analysis of the published literature is developed in order to know the characteristics of this body of knowledge and its development over time, understanding the evolution and trends within the research disciplines requires the combination of methods and tools that guarantee equality and replicability within these exercises. In that context, this article implements analysis is based on a systematic and exhaustive search strategy of the evolution of the HCI literature, using a combination of quantitative methods, which includes a quality analysis for the delimitation of the simple analysis of the identified publications
- PublicaciónAcceso abiertoAnálisis de las redes de colaboración entre las Instituciones de Educación Superior en Colombia de acuerdo con ResearchGate(2020-04-05) Pertuz-Peralta, Vanessa Paola; Perez-Orozco, Adith Bismarck; Vega-Molina, Adriana Lorena; Aguilar-Avila, Jorge; Nuevas TecnologíasEl objetivo del presente artículo es analizar las redes de colaboración entre las Instituciones de Educación Superior (IES) en Colombia de acuerdo con el parámetro de “Top collaborating institutions” en ResearchGate. El artículo efectúa una comparación entre las redes de las Instituciones de Educación Superior acreditadas en alta calidad y las no acreditadas, de acuerdo con los lineamientos del Sistema Nacional de Acreditación en Colombia. El análisis de la colaboración institucional se realiza mediante la construcción de redes de trabajo conjunto, en el programa UCINET; se considera la primera universidad registrada en el “Top collaborating institutions” publicado en perfil de ResearchGate de cada Institución de Educación Superior. Los resultados demuestran que las instituciones acreditadas poseen una red de colaboración bien conectada e integrada. Por el contrario, las instituciones no acreditadas poseen una red de colaboración débil y poco interconectada. Además, las instituciones no acreditadas buscan colaborar principalmente con IES acreditadas y no entre ellas. De esta manera, los esfuerzos de las instituciones no acreditadas no están bien coordinados y se diluyen en la distribución de sus relaciones colaborativas
- PublicaciónAcceso abiertoAnálisis del desarrollo de los Parques Científicos - Tecnológicos (PCTS) en Colombia(2015-01-15) Angulo Cuentas, Gerardo; Camacho Pico, Jaime; Romero Riaño, EfrénScience Technology Parks (STP), or Technology Parks (TPs), have been studied mainly in developed countries contexts. Responding to this knowledge gap, this article presents a characterization of TPs initiatives development process in Colombia through a multiple case study of parks recognized by the TPs national policy, and a comparative analysis development of them, from the point of view of five models identified in TPs literature. Typically, a TP must take on average, ten years to reach its third phase of development or maturity phase. In Colombia, the development of TPs, there are not the typical behavior because after twelve years of support provided by the Colombian state for these projects, with the enactment of TPs National Policy, three parks keep in incubation stage, as projects; the leading institution until 2012, Antioquia Technology Park announced its liquidation; and Guatiguará Technology Park although of advances in its development process, keeps in the incubation stage. Research results include identification of differentiating variables in the development of the two most developed TPs initiatives in Colombia and one analysis of future prospects of research fields.
- PublicaciónAcceso abiertoAnálisis espacial de riesgo de morbilidad y mortalidad por COVID-19 en Europa y el Mediterráneo en el año 2020(2020-10-27) Andrades-Grassi, Jesús Enrique; Cuesta-Herrera, Ledyz; Bianchi-Pérez, Guillermo; Grassi, Hilda Cristina; Lopez-Hernandez, Juan Ygnacio; Torres-Mantilla, Hugo; GaiaDisease mapping seeks to represent the risk of a disease. This paper focuses on the spatial analysis of risk for pandemic COVID-19 in Europe and the Mediterranean. Morbidity and mortality data for 54 countries in ratio format were used. Two hypotheses were considered, the first one is that the data are homogeneous and the second one is that the ratios are defined in a heterogeneous manner requiring the stratification on the basis of covariables and the methodology of Jenks’ intervals. Spatial risk models were applied as well as methods for the representation of clusters. The results show that the best representation is obtained with the Poisson-Gamma Model under stratification. The variations in the ratios are due to the individual policies of each country for the management of the pandemic. The cluster analysis shows that there is a high mortality process in Eastern Europe. The behavior of the pandemic should be evaluated in the space-time process as well as in other heterogeneous and highly unequal regions.
- PublicaciónAcceso abiertoApplication of project management tools in engineering services companies : Four case studies(2018) Romero, Sara María; Bohorquez, L.F.; Rojas Puentes, M.P.A methodological proposal is designed for the planning of the scope, time and cost that strengthens the management of the projects developed by the services companies of Cúcuta and its metropolitan area. In the first phase, a descriptive study was carried out based on a maturity diagnosis which included the relevant tools to measure the culture in the planning of the scope, time and cost of the projects, which was validated by experts in PMI and applied in thirty companies to the officers who are in charge of the management of the projects. The second stage consisted in the selection of fifteen tools and techniques of the scope, time and cost management of the PMBOK Guide applicable in the methodological proposal according to the diagnosis. Finally, methodological guidelines for project management were designed in four social services companies, technology and computer science and civil constructions in which the tools defined in the proposal were incorporated, which will become guidelines for the execution of the projects guaranteeing the fulfilling of the deliverables, in the estimated time and with the assigned budget.
- PublicaciónAcceso abiertoApplication of the calculus of variations to the vertical cut off in cohesive frictionless soil(1981-05-02) Castillo, E.; Luceiio, A.; De Joesselin De Jong, G.
- PublicaciónAcceso abiertoAprendizaje organizacional en una empresa minera en Colombia(2020-03-21) Morales-Alvis, Ketty Johana; Pertuz-Peralta, Vanessa Paola; Perez-Orozco, Adith Bismarck; Vega-Molina, Adriana Lorena; Nuevas TecnologíasEl objetivo del artículo es analizar los niveles de aprendizaje organizacional en una empresa de explotación de carbón en el Departamento de La Guajira. La investigación considera un estudio de tipo descriptivo, de campo, no experimental. Se aplicó un cuestionario de recolección de datos conformado por 43 ítems a una muestra de 46 trabajadores de tres áreas de una mina de carbón en el departamento de La Guajira. Los resultados de la correlación indican que la mayor relación se da entre los niveles de aprendizaje grupal y organizacional. Adicionalmente, el análisis de varianza (ANOVA) indica que no existen diferencias significativas en el aprendizaje organizacional en los niveles en la empresa analizada. Se concluye que el nivel de aprendizaje individual, grupal y organizacional se encuentra presente, mientras que el nivel de aprendizaje organizacional se encuentra muy presente en la empresa analizada.
- PublicaciónAcceso abiertoAprendizaje Organizacional: Análisis de la Exploración y Explotación de Conocimiento en Medianas Empresas(2019-06-05) Pertuz-Peralta, Vanessa Paola; Perez-Orozco, Adith Bismarck; Geizzelez, María Lourdes; Vega-Molina, Adriana Lorena; Nuevas TecnologíaEl objetivo del artículo es analizar las actividades para el aprendizaje organizacional en medianas empresas. El artículo analiza las actividades de exploración y explotación de conocimiento. La investigación considera un estudio de tipo descriptivo, de campo, no experimental. Se aplicó un cuestionario de recolección de datos a una muestra de 44 medianas empresas en Valledupar, Colombia. Los resultados destacan la presencia de actividades de exploración y explotación de conocimiento en las empresas analizadas. Adicionalmente, los resultados indican que no existen diferencias significativas en el desarrollo de estas actividades en las empresas objeto del presente estudio.
- PublicaciónAcceso abiertoAssessment of the energy recovery potential of oil sludge through gasification aiming electricity generation(2021-01-15) Castillo Santiago, York; Martínez-González, Aldemar; Venturini, Osvaldo José; Yepes Maya, Diego Mauricio; GAIAThermochemical conversion of oil sludge (OS) residues from crude oil refinery was studied as an alternative for treatment and energy recovery before OS final disposal. A simulation model for OS gasification was developed and validated by using AspenPlus™ V 11.0. Three scenarios by considering different gasifying agents were evaluated, aiming the assessment of different gasification parameters and performance indexes such as gasification temperature, cold-gas efficiency, syngas yield, and LHV. To evaluate the potential use of syngas to generate electricity, three different prime movers such as steam Rankine cycle, gas microturbine, and gas-Internal Combustion Engine (ICE) were modeled. A hydrogen-rich syngas from OS gasification with air/steam mixture was reached (38.2 vol%) at ER 0.20. Syngas LHV and syngas yield ranged between 8.6 and 3.0 MJ/Nm3 and 0.6–1.3 Nm3/kg OS, when ER was increased from 0.25 to 0.45, respectively. The highest energy recovery potential (electricity generation) was obtained when using syngas to power a gas-ICE, with a generation index of about 0.47 kWh/kg-OS at ER ratio of 0.25. Therefore, OS thermochemical conversion into syngas and its subsequent use to generate electricity could be a technological alternative to oily residues management inside an oil refinery that could efficiently transform a dangerous residue into electricity.
- PublicaciónAcceso abiertoBench-scale bubbling fluidized bed systems around the world - Bed agglomeration and collapse: A comprehensive review(2021-05-25) Machado Nascimento, Francisco Regis; Martínez-González, Aldemar; Silva Lora, Electo Eduardo; Ratner, Albert; Escobar Palacio, Jose Carlos; Reinaldo, Rafaela; GAIAThermochemical conversion by gasification process is one of the most relevant technologies for energy recovery from solid fuel, with an energy conversion efficiency better than other alternatives like combustion and pyrolysis. Nevertheless, the most common technology used in the last decades for thermochemical conversion of solid fuel through gasification process, such as coal, agriculture residues or biomass residues are the fluidized bed or bubbling fluidized bed system. For these gasification technologies, an inert bed material is fed into reactor to improve the homogenization of the particles mixture and increase the heat transfer between solid fuel particles and the bed material. The fluidized bed reactors usually operate at isothermal bed temperatures in the range of 700–1000 °C, providing a suitable contact between solid and gas phases. In this way, chemical reactions with high conversion yield, as well as an intense circulation and mixing of the solid particles are encouraged. Moreover, a high gasification temperature favours carbon conversion efficiency, increasing the syngas production and energy performance of the gasifier. However, the risk of eutectic mixtures formation and its subsequent melting process are increased, and hence the probability of bed agglomeration and the system collapse could be increased, mainly when alkali and alkaline earth metals-rich biomasses are considered. Generally, bed agglomeration occurs when biomass-derived ash reacts with bed material, and the lower melting temperature of ash components promotes the formation of highly viscous layers, which encourages the progressive agglomerates creation, and consequently, the bed collapse and system de-fluidization. Taking into account the relevance of this topic to ensure the normal gasification process operating, this paper provides several aspects about bed agglomeration, mostly for biomass gasification systems. In this way, chemistry and mechanism of bed agglomeration, as well as, some methods for in-situ detection and prediction of the bed agglomeration phenomenon are reviewed and discussed.
- PublicaciónAcceso abiertoCalibration of the aquacrop model in special coffee (Coffea Arabica) crops in the Sierra Nevada of Santa Marta, Colombia(2018) Vega Molina, Adriana Lorena; Pertuz Peralta, Vanessa Paola; Pérez Orozco, Adith Bismarck; Ortiz Iglesias, María Isabel; González Guerrero, EnriqueBackground and Objective: This study proposed the application of the AquaCrop model in special coffee crops. Till now, no studies were found on the application of this model in this specific crop, which is the main contribution of this research study. In this way, the study aims to present the calibration of the variables related to type of crop, soil characteristics and management of special coffee agriculture in the Sierra Nevada of Santa Marta, Colombia. Materials and Methods: The theoretical bases considered for the present study focus on the different calibration methodologies of the AquaCrop model in different types of crops. The methodology used is based on the proposal of estimation, measurement, calculation and collection of the respective data of the model. Specifically, the project analyzed databases of climate, soil, crops and management practices. The researchers used the statistical techniques of ordinary least squares and the completion coefficient to perform the fit of the model. Results: The results of the calibration of AquaCrop for coffee (Coffea arabica) special have a coefficient of determination R2 of 0.71 which indicates that the model is acceptable. In addition, it established a forecast of productivity with specific agroclimatic conditions. According to the calibrated model, the average temperature is the variable with the highest incidence in coffee productivity. Conclusion: The results presented in this paper contribute to the application of the AquaCrop model in coffee crops in different regions.
- PublicaciónAcceso abiertoEl cambio tecnológico en el caso de los textiles inteligentes : Una aproximación desde las capacidades dinámicas(2016) Torres Barreto, Martha Liliana; Martínez, José Noel; Meza Ariza, Lucelly Carolina; Muñoz Molina, Leda PazLa industria de la confección de prendas de vestir pertenece a uno de los sectores más tradicionales de la economía, precisamente por estar vinculado a una necesidad básica del ser humano: el vestir. No obstante, durante la última década se está perfeccionando la oferta de nuevos textiles llamados "inteligentes" por sus interacciones con el entorno, ya que integran sensores y actuadores que permiten detectar y responder frente a diversos estímulos, siendo cada vez más livianos, durables y sobre todo: útiles. El surgimiento de esta nueva era de los textiles da pie a un sinnúmero de aplicaciones y la posibilidad para que empresas tradicionales de textil y confección exploren nuevos mercados, apoyadas en el desarrollo de capacidades dinámicas que les permitan mantener ventajas competitivas sostenibles. Este trabajo propone un modelo bajo el cual un conjunto de capacidades de aprendizaje sumadas a ciertas capacidades de absorción y de innovación, pueden gestar un cambio tecnológico en el sector textil confección, que necesariamente deberá verse apoyado en otro sector como el de las Tecnologías de Información y Comunicaciones.