12456 research outputs found
Sort by
Gestión del riesgo de desastres en el municipio de Suan sur del departamento del Atlántico diez años después de la inundación
No full textEn 2010, el sur del departamento del Atlántico, Colombia, sufrió un fuerte impacto en sus formas de habitar el territorio y el bienestar de sus familias, debido al desbordamiento del canal del Dique que causó la inundación del
Territorio y llevó a la reformulación de la política de Gestión de Riesgos en el país. La presente investigación se orientó como estudio de caso a caracterizar geográfica y sociodemográficamente las amenazas que se encuentran presentes en el municipio de Suan (Atlántico, Colombia), identificar medidas que desde el sistema de gestión de riesgo a nivel territorial se han venido implementando y evaluar la perspectiva y disposición a la gestión del riesgo en las comunidades diez años después de la inundación. La investigación de tipo cualitativo descriptivo se basó en revisión documental de fuentes secundarias como los planes de desarrollo, esquemas de ordenamiento territorial, entre otros. También se obtuvo información de fuentes primarias a partir de encuestas, con las que se exploró la percepción de los habitantes del municipio sobre sus condiciones de vida y las amenazas a las que se encuentran expuestos, así como a su disposición frente a la gestión del riesgo de desastres. Se proponen reflexiones importantes para considerar en el marco de la implementación de las políticas de gestión del riesgo, en cumplimiento de la Ley 1523, pero specialmente desde una noción que integra la gestión del riesgo y el desarrollo sostenibleIn 2010, the southern region of the Atlántico department in Colombia experienced a significant impact on its territorial habitation patterns and the well-being of its families, due to the overflowing of the Dique canal which caused the flooding of the area and led to the reformulation of Risk Management policies in the country. This research was oriented as a case study to geographically and sociodemographically characterize the threats present in the municipality of Suan (Atlántico, Colombia), identify measures that have been implemented from the territorial-level risk management system, and evaluate the perspective and disposition towards risk management in the communities ten years after the flood. The descriptive qualitative research was based on document review of secondary sources such as development plans, territorial planning schemes, among others. Information was also obtained from primary sources through surveys, which explored the perception of the municipality's inhabitants regarding their living conditions and the threats they are exposed to, as well as their disposition towards disaster risk management. Important reflections are proposed to be considered within the framework of the implementation of risk management policies, in compliance with Law 1523, but especially from a notion that integrates risk management and sustainable development.Lista de tablas 6-- Lista de figuras 7-- Introducción 13-- Planteamiento del problema 16-- Objetivos 20-- Objetivo General 20-- Objetivos Específicos 20-- Marco Teórico 21--Del manejo de desastres a la perspectiva de gestión del riesgo 21-- Conocimiento del riesgo 25--Reducción del riesgo 27--Manejo de desastres 28-- Comunidades expuestas: entre la vulnerabilidad y la adaptación 29-- La vulnerabilidad al riesgo de desastres 30-- Estado del arte 34-- Metodología 39-- Revisión ocumental 39-- Trabajo de campo 40-- Resultados 41-- Caracterización geográfica y demográfica que delimita las zonas en riesgo de desastres del municipio de Suan. 41-- Características geográficas y físicas 41-- Hallazgos del mapeo georreferenciado 44-- Características sociodemográficas 48-- Medidas de gestión del riesgo de desastres implementadas desde la dirección del sistema a nivel territorial y su contribución en el conocimiento, reducción y manejo del riesgo en el municipio de Suan 59-- Perspectiva y disposición a la gestión de riesgo de desastres en las comunidades cercanas a las zonas identificadas como de posible mayor afectación 76-- Discusión 81-- Conclusiones 84-- Referencias 86Magíster en Desarrollo SostenibleMaestrí
Enhancing dye-sensitized solar cell performance: optimizing Cu2ZnSnS4/ZnCo2O4 nanocomposites as efficient and cost-effective counter electrodes.
No full textThis study investigates the utilization of Cu2ZnSnS4/ZnCo2O4 (CZTS/ZCO) nanocomposites prepared through hydrothermal and combustion methods as counter electrodes in Dye-Sensitized Solar Cells (DSSCs). Different ratios of Cu2ZnSnS4 and ZnCo2O4 were explored, and comprehensive analyses were conducted using X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), High-Resolution TEM (HRTEM), Brunauer–Emmett–Teller (BET) surface area analysis, Raman Spectroscopy, Electrochemical Impedance Spectroscopy (EIS), cyclic voltammetry (CV), Tafel analysis, Field Emission Scanning Electron Microscopy (FESEM), and Incident Photon-to-Electron Conversion Efficiency (IPCE), alongside long-term stability assessments. The CZTS:ZCO ratio of 2:1 exhibited the highest efficiency, reaching 8.81 %, with an open-circuit voltage of 729 mV, short-circuit current of 17.80 mAcm−2, and a fill factor of 67.9 %. This surpasses the efficiency of the reference Pt cell (8.42 %), which had an open-circuit voltage of 735 mV, short-circuit current of 17.16 mAcm−2, and a fill factor of 66.8 %. The average crystallite sizes for the main peaks of CZTS and ZCO samples were estimated to be 19.8 and 16.7 nm, respectively. The crystallite size can significantly affect the charge transfer and conductivity in the counter electrode during electrochemical processes; the presence of nanocrystals with these sizes can notably enhance the electrochemical properties and conductivity of the synthesized samples. Raman analysis results indicate that no additional phases or secondary phases such as ZnS and CuSnS3 have formed in the kesterite CZTS structure, and the crystal has formed as a single phase. Additionally, the F2g modes in the Raman spectrum of ZCO indicate tetrahedral units in the spinel ZCO structure, and the A1g modes represent octahedral structures in this phase, indicating the formation of suitable ZCO phase. The superior performance of the CZTS/ZCO nanocomposite can be attributed to its enhanced crystalline structure, superior charge transport characteristics, and improved electrocatalytic behaviours
The role of the State in the development of agribusiness. A case study
No full textEl desarrollo optimo de las actividades agroindustriales por parte del Estado implica considerar determinantes de índole económico, social, geográfico y político contempladas en unas políticas públicas sectoriales encaminadas a los procesos de articulación (gobierno-empresa). En tal sentido, las actividades económicas enmarcadas en los sectores económicos, agropecuario e industrial, pueden propiciar vínculos intersectoriales, formando cadenas productivas según las condiciones de las regiones, que en el presente estudio corresponde al departamento de Sucre; ello en consideración a que el departamento de Sucre es de vocación agropecuaria, así lo corroboran los indicadores (42,5%) del Departamento Administrativo Nacional de Estadísticas (DANE) pero a través de los años ese protagonismo se ha tornado en receso, bajando su representación como sector al 35,1%, lo que conlleva a bajos encadenamientos y a poco o nulo valor agregado, siendo pertinente el análisis para conocer las incidencias de las políticas gubernamentales encaminadas al desarrollo agroindustrial del departamento de Sucre; de allí lo adelantado en esta investigación, arrojando como primeros datos de importancia, la notoria desarticulación entre los planes de desarrollo y las necesidades en los actores de la cadena que en ningún momento, o al menos de manera excepcional, priorizan un frente para dinamizar la agroindustria a nivel departamental.The optimal development of agro-industrial activities by the State implies considering economic, social, geographic and political determinants contemplated in sectoral public policies aimed at articulation processes (government-business). In this sense, the economic activities framed in the economic, agricultural and industrial sectors can promote intersectoral links, forming productive chains according to the conditions of the regions, which in this study corresponds to the department of Sucre; This is in consideration of the fact that the department of Sucre has an agricultural vocation, as corroborated by the indicators (42.5%) of the National Administrative Department of Statistics (DANE), but over the years this prominence has declined, lowering its representation as a sector to 35.1%, which leads to low linkages and little or no value added, making the analysis relevant to know the impact of government policies aimed at agroindustrial development in the department of Sucre; The first important data that emerged from this research is the notorious disarticulation between development plans and the needs of the actors in the chain, who at no time, or at least exceptionally, prioritized a front to boost agroindustry at the departmental level
Guías de laboratorio de mecánica de fluidos: ingeniería mecánica
No full textEl compendio de guías de laboratorio de mecánica de fluidos mecánica incluye prácticas que les permiten a los estudiantes fortalecer habilidades al aplicar conceptos de la asignatura en un ambiente de laboratorio. Esta guía articula experiencias fundamentales que incluyen normativa de seguridad aplicable, recursos a utilizar, procedimientos, cálculos y un cuestionario de análisis. Con ello, los estudiantes podrán consolidar los conocimientos teórico-prácticos al aplicar conceptos de las temáticas de la asignatura mecánica de fluidos mecánica.Propiedades de los Fluidos - Densidad 4 -- 1. Introducción 5 -- 2. Objetivo 6 -- 3. Normativa de seguridad 6 -- 4. Recursos 7 -- 5. Procedimiento experimental 8 -- 6. Cálculos 8 -- 7. Cuestionario 9 -- 8. Preguntas para investigación 10 -- 9. Referencias 10 -- 10. Pre informe 10 -- Pre informe experiencia 1 11 -- Propiedades de los fluidos - viscosidad 13 -- 1. Introducción 14 -- 2. Objetivo 15 -- 3. Normativa de seguridad 15 -- 4. Recursos 16 -- 5. Procedimiento experimental 17 -- 6. Cálculos 17 -- 7. Cuestionario 18 -- 8. Preguntas para investigación 18 -- 9. Referencias 18 -- 10. Pre informe 19 -- Pre informe experiencia 1 20 -- Teorema de bernoulli 21 -- 1. Introducción 23 -- 2. Objetivo 24 -- 3. Normativa de seguridad 24 -- 4. Recursos 25 -- 5. Procedimiento experimental 26 -- 6. Cálculos 26 -- 7. Cuestionario 28 -- 8. Preguntas para investigación 28 -- 9. Referencias 29 -- 10. Pre informe 29 -- Pre informe experiencia 1 3
Correction: clinical inertia in newly diagnosed type 2 diabetes mellitus among patients attendingselected healthcare institutions in Colombia
No full textCorrection: Diabetology & Metabolic Syndrome (2024) 16:42 https://doi.org/10.1186/s13098-023-01245-0 The copyright holder for this article was incorrectly given as “Battelle Memorial Institute, under exclusive licence to Springer Nature Switzerland AG 2024” but should have been “© Merck & Co., Inc., Rahway, NJ, USA and its affiliates and Nelson Alvis- Guzman, Martín Romero
A vendor-managed inventory model for a three-layer supply chain considering exponential demand, imperfect system, and remanufacturing
No full textThis paper presents a vendor-managed inventory model for a three-layer supply chain comprised of suppliers, manufacturers, and retailers. This model considers an imperfect production system with a deterministic percentage of defective and deteriorated items, exponential demand for perishable products, and operational costs. The VMI model maximizes the benefits, assuming a Stackelberg approach to find the optimal values of replenishment lot sizes, production rates, selling prices, and product cycle length. A solution algorithm is developed to find the optimal solutions. A case study of the Dairy Industry for highly perishable products is provided to illustrate the applications, evaluate the performance, and obtain managerial insights. The results show that the percentage of defective and deteriorated items and remanufacturing rates are crucial in replenishment, production, and selling policies. The VMI agreement includes remanufacturing defective products to obtain new dairy derivates. The deteriorated products can be sold as near-expired products or inputs for compost, fertilizers, etc. Finally, some conclusions and future research lines are provided
Influence of pressure and temperature on the flexible behavior of Iron-Based MIL-53 with the CO2 host: a comprehensive experimental and DFT study
No full textThis research focuses on developing MIL-53-type compounds with Fe obtained with ligands derived from PET waste, followed by the controlled addition of hydrofluoric acid (HF). Incorporating HF into the MOF structure induced substantial changes in the material textural properties, resulting in a significant change in CO2 adsorption. Furthermore, a distinctive structural alteration (breathing effect) was observed in the CO2 isotherms at different temperatures; these structural changes have not been observed by X-ray diffraction (XRD) because this characterization has been performed at room temperature, whereas the adsorption experiments were conducted at 260, 273, and 303 K and different pressures. Subsequently, DFT studies were performed to investigate the CO2-filling mechanisms and elucidate the material respiration effect. This approach offers promising opportunities for sustainable materials with improved gas adsorption propertie
A machine learning model for predicting the risk of perinatal mortality in low-and-middle-income countries: A case study
No full textPerinatal mortality is the death that happens between 22 weeks of gestation and the first seven days of birth. This has become an essential indicator for measuring the quality of maternal and childcare in Low-and-Middle-Income Countries (LMICs). Tools based on Artificial Intelligence (AI) have emerged with immediate relevance in medical contexts, more precisely with Machine Learning (ML) tools due to the ability to learn from past and present observations and be able to generate future predictions, promising positive results in maternal and childcare processes. This paper presents a Random Forest (RF) model for predicting the risk of perinatal mortality in LMICs. We initially characterized the prenatal control process in LMICs. Second, potentially predictive features of perinatal mortality were identified considering the literature review and medical expertise. Subsequently, a data pre-processing procedure was executed to improve the data quality. The RF algorithm was employed to model the risk of perinatal mortality based on social and clinical variables. A case study in a Colombian healthcare institution was used to validate the proposed approach. The results show an RF model with an accuracy of 99.16%, sensibility = 87.50%, and specificity = 100%
A mixed integer programming optimization model for mining truck dispatch policies using traffic constraints: Case of a copper mine in northern Chile
No full textProductivity in open pit operations in the mining industry is conditioned by the manual assignment of trucks by the dispatcher, who does not have the ability to find the optimal policy by himself, having many variables that consider. To this end, an MIP optimization model is proposed that considers the scheduling of a discretized operating shift in smaller stages that consider positions and capacities of available trucks, and congestion based on a differential speed based on the number of trucks in different sections of the transport route. The model seeks to prioritize the transfer of material to crushers and meet material goals during the planning horizon. Preliminary results indicate that it is possible to reduce the violation of the production plan by destination by 12% and increase productivity by 46% with respect to the state of the art of similar solutions
Improvement in measurement of radiation based two-phase flowmeters independent of flow regime and scale thickness using ant colony optimization and GMDH
No full textThe formation of scales in pipes is one element that has a major impact on the efficiency of machinery used in the oil and gas sector. With the help of artificial intelligence, this new, non-invasive device was able to figure out the volume fraction of a two-phase flow by taking into account the thickness of the scale in the tested pipeline. The proposed design uses an isotope pair of barium-133 and cesium-137 as a dual-energy gamma generator. One detector records photons that are transmitted, and another detector records photons that are scattered. The signals from the detectors were simulated using the Monte Carlo N-Particle (MCNP) code, and then ten frequency and wavelet characteristics were extracted. To choose the best inputs from the collected features for computing the volume fraction, an ant colony optimization (ACO)-based method is applied. Six attributes, representing the optimal combination, were developed using this method. In order to forecast the volume percentage of two-phase flows independently of flow regime and scale thickness, we fed the characteristics introduced by ACO into a group method of data handling (GMDH) neural network. Volume fraction calculations had a maximum RMSE of 0.056, which is quite little compared to previous research. By using the ACO to choose the best characteristics, the current work has significantly increased its accuracy in identifying volume fraction