Universidad Tecnológica de Bolívar
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Urban mobility insights: a dataset for exploring network topology and city dynamics
No full textThis article presents a comprehensive dataset capturing the urban network structures and
sociodemographic variables of 65 cities worldwide for the year 2023, based on the Urban Mobility
Readiness Index (UMRi) developed by the Oliver Wyman Forum. The dataset includes key metrics
such as graph entropy, node degree, clustering coefficient, graph diameter, GDP per capita, and
population density, among others, which are essential for analysing the relationship between
network topology and urban mobility readiness. By offering detailed insights into these urban
networks, this dataset serves as a valuable resource for cities not currently included in major
mobility rankings, allowing them to evaluate their mobility readiness in relation to established
indices like the UMRi. Urban planners and researchers can leverage this data to explore complex
urban mobility dynamics and develop strategies to enhance transportation systems, particularly in
rapidly growing or underserved regions. The dataset is structured for seamless integration with
various analytical tools, making it a vital asset for both urban planning and research aimed at
fostering sustainable and efficient urban development
A Study on the Impact of Temperature Variations on the Pyrolysis of Corn-cob Waste (zea Mays) for Bioenergy Production
No full textContiene ilustraciones, gráficos.Thermogravimetric analysis (TGA) characterized the thermal stability and degradation of corn-cob waste (Zea mays). Results indicate that exposure to temperatures exceeding 240 °C causes approximately 50% mass loss. At this temperature, the drying stage removed traces of moisture and some low molecular weight aromatic molecules. The degradation of corn-cob waste was carried out through pyrolysis in a Nitrogen (N2) atmosphere, with these tests being carried out at 500, 550 and 600 °C, in order to observe how the variation in temperature affects the characteristics of the solid products obtained, to know their stability, tests are carried out on each of the solid products at each indicated temperature; While 550 °C exhibited the highest percentage of weight loss, 600 °C was selected. This choice maintains a gradual progression in the percentage of weight loss, even though 500 °C and 600 °C showed similar mass loss values.
Finally, FTIR tests were implemented, which were responsible for decoding the signal, which results in the generation of spectra that are used to identify or quantify the material existing in the samples. According to the results, it is inferred that the pyrolysis of corn-cob waste has caused the elimination of the molecules responsible for the vibrations of the O-H, C-H, and C-O bonds. This loss could be explained by the degradation of polysaccharides; Instead, the bonds CO, CH, C=C, C=O, CO and CH are conserved, the latter being commonly found in ethers and aromatic compounds that include hydroxyl groups.1. Introduction
2. Methodology
2.1 Geographical origin of corn-cob (Zea mays) samples
2.2 Physicochemical characterization
3. Results
3.1 Assessment of solid products from the corn-cob waste pyrolysis process, based on temperature using FTIR
3.2 Thermogravimetric analysis of solid waste from the pyrolysis process at different temperatures
4. ConclusionsControl de la contaminación de los recursos (agua, aire y suelo
Astrobiology and planetary sciences in Colombia
No full textContiene ilustraciones, fotografías.This chapter presents a historical and contemporary review of the devel- opment of astrobiology and planetary sciences in Colombia, highlighting their ori- gins, progress, and future projections. Beginning with the emblematic fall of the Santa Rosa de Viterbo meteorite in 1810—an event that symbolizes the country’s initial engagement with cosmic knowledge—the chapter traces the key milestones in research, education, outreach, and the formation of scientific communities. It examines the early initiatives in exobiology, the consolidation of research groups, the role of museums and planetariums, as well as strategies for the social appropriation of scientific knowledge. Furthermore, it explores major research lines in extreme environments and planetary analogs, alongside the development of educational programs and specialized scientific events. Finally, it outlines the per- spectives that position Colombia as an emerging actor in the field of space sci- ences, leveraging its biodiversity, geodiversity, and the strengthening of interdisciplinary networks.1. Introduction
2 First Steps
3. Science Outreach and Public Communication of Science
4 Education
5 Scientific Research
6 Perspectives
7. ReferencesNo Aplic
Diseño e Implementación de Banco de laboratorio de control de nivel de dos tanques interconectados en paralelo
No full textEste proyecto se enfoca en el diseño e implementación de un banco de laboratorio de control avanzado a partir de un diseño estructural preexistente, con el fin de que estudiantes de pregrado, maestría y doctorado de la Universidad Tecnológica de Bolívar puedan realizar prácticas y experimentos en el área de control Industrial, digital e Inteligente. El sistema consiste en un problema de mecánica de fluidos del control de dos tanques interconectados en paralelo (sistema no lineal) con dos bombas, dos variadores de frecuencia, dos controladores físicos PID y una tarjeta de adquisición de datos (DAQ) que se opera en tres modos: Manual, PID (físico) y PC (Manual, PID, PID con desacopladores). La solución propuesta abarca el diseño eléctrico y electrónico (circuito de alimentación, circuito de mando y tablero eléctrico), mantenimiento y calibración de dispositivos e instrumentos, modelamiento del sistema, programación, diseño de interfaz en LabVIEW e implementaciónIngeniero MecatrónicoPregrad
Electrification as a development and sustainability approach in rural areas using renewable energy sources
No full textBACKGROUND AND OBJECTIVES: Within the Colombian Caribbean region, a number of rural
communities utilize self-generated energy as a result of their limited access to the national
electricity network. This energy generated is achieved through a combination of combustion
engines and renewable sources. However, certain communities face challenges maintaining
daily energy autonomy, resulting in developmental disparities. Consequently, the study seeks
to create a method for evaluating the accessibility of renewable resources and performing
risk assessments to facilitate the introduction of electrification projects in rural regions of the
Colombian Caribbean.
METHODS: A review was made of the feasibility of financing projects with a focus on
renewable energies by government financing entities in Colombia. Subsequently, risk
mitigation strategies were utilized in projects of this kind, analyzing the available renewable
resources in the locality such as wind and photovoltaic solar energy.
FINDINGS: The main factor impeding the success of renewable energy projects in the
Colombian Caribbean is political risk. Despite the region’s significant solar and wind energy
potential, as demonstrated by statistical analyses based on meteorological data, these
projects frequently struggle to achieve optimal operational outcomes due to political
instability. Presenting potential solar radiation levels ranging from 5 kilowatt-hours per square
meter per day, and wind speeds exceeding 2 and 7 meters per second in certain localities.
The aforementioned statement suggests that the projects that have been signed are backed
by insufficient dimensioning.
CONCLUSION: The strategies devised for effective administration of energy supply to these
communities are outlined, taking into account the assessment of wind and solar energy
capacities specific to each area, as well as the identification of potential political and financial
risks which pose the most significant uncertainties for such initiatives. The solar radiation
assessments obtained are conducive to accurately sizing photovoltaic systems, while the
identified wind speeds indicate a need to reevaluate methods for harnessing these wind
resources efficientlyUniversidad Tecnológica de Bolíva
Estilos de aprendizaje de los estudiantes de la Corporación Educativa La Concepción y su relación con el rendimiento académico en el área de matemáticas.
No full textEste proyecto de investigación se propuso determinar la relación entre los estilos de aprendizaje con el rendimiento académico de los estudiantes de grado 6°, 7°, 8° y 9° en el área de matemáticas del colegio La Concepción. Se utilizó un enfoque cuantitativo de tipo descriptivo-explicativo. La población participante fue de 249 estudiantes quienes diligenciaron el cuestionario CHAEA. Los datos se procesaron con el software SPSS, aplicando el modelo de Regresión Logística Binaria y se analizaron en función del rendimiento académico; posteriormente se analizaron los resultados de género, la edad, el grado y los estilos de aprendizaje. Los hallazgos demostraron la predominancia del estilo de aprendizaje Pragmático y Activo en relación con el rendimiento académico. Así mismo, se encontró significancia entre la variable género, grado y el rendimiento académico. Finalmente, no hubo significancia entre el estilo de aprendizaje Reflexivo y Teórico con el rendimiento académico. Y tampoco hubo significancia entre la variable edad y el rendimiento académico. Estos resultados sugieren hacer uso de estrategias pedagógicas adaptadas a los estudiantes favoreciendo los estilos de aprendizaje Pragmático y Activo
Modelagem e simulação de reatores fotocatalíticos de filme descendente: uso da dinâmica de fluidos computa- cional (CFD) para análise de sistemas multifásicos
No full textLa dinámica computacional de fluidos (CFD) se perfila como una herramienta apropiada para el modelamiento de procesos fotocatalíticos heterogéneos, pues permite considerar simultáneamente los diferentes fenómenos físicos trascendentales de los procesos. En el presente estudio se empleó el software COMSOL Multiphysics para modelar el régimen de flujo y determinar la distribución de las partículas de catalizador en un reactor fotocatalítico de película descendente, hecho relevante para determinar la eficiencia del reactor. Las simulaciones del reactor fueron realizadas con el módulo de Mezclas de COMSOL, en un régimen de flujo turbulento empleando el enfoque de RANS. Se detectaron siete zonas definidas con un perfil particular de concentración de catalizador en toda el área de la película, para las cuales se estimó la absorción fotónica en el reactor con el modelo de seis flujos (SFM). De ello se obtuvo que existe una diferencia de más del 20% entre el mayor y el menor valor del promedio de la absorción fotónica en el área reactiva, con lo que se puede esperar que la variación en la degradación de los contaminantes en estas zonas oscile entre el 10 y el 20%, lo cual debe tenerse en cuenta para la aplicabilidad de la tecnología.Computational fluid dynamics (CFD) is emerging as an appropriate tool for modeling heterogeneous photocatalytic processes, since it allows simultaneous consideration of the different physical phenomena involved in the processes. In the present study, COMSOL Multiphysics software was used to model the flow regime and to determine the distribution of catalyst particles in a falling film photocatalytic reactor, which is relevant to determine the reactor efficiency. The reactor simulations were performed with the COMSOL Mixture module in a turbulent flow regime using the RANS approach. Seven defined zones were detected having a particular catalyst-concentration profile over the entire film area, for which the photonic absorption in the reactor was estimated with the six-flux model (SFM). From this it was obtained that there is a difference of more than 20% between the highest and the lowest value of the average photonic absorption in the reactive area, so it can be expected that the variation in the degradation of pollutants in these zones ranges between 10 and 20%, which should be taken into account for the applicability of the technology.Universidad Tecnológica de Bolívar/Universidad del Vall
Revisão narrativa do caso da vacina contra o HPV em El Carmen de Bolívar, Colômbia (2014-2021)
No full textIntroducción: en 2014 centenares de mujeres adolescentes del municipio rural de El Carmen de Bolívar (Colombia)experimentaron extraños síntomas tras ser vacunadas con Gardasil, una de las vacunas contra el Virus del Papiloma Humano (VPH). Las autoridades sanitarias no hallaron un vínculo causal entre la vacunación y los síntomas, por lo que atribuyeron el fenómeno a una posible reacción psicógena masiva. Las familias de las afectadas rechazaron esta hipótesis. El caso reveló la existencia de una controversia entre la comunidad científica colombiana en torno a la seguridad de la vacuna. La persistencia en el tiempo del problema de salud y su carácter masivo influyeron en un drástico descenso de la cobertura de vacunación, y la Corte Constitucional dictaminó en 2017 el uso obligatorio del consentimiento informado durante el procedimiento de vacunación.
Metodología: se presenta una revisión narrativa de carácter integral actualizada sobre la literatura publicada entre2014 y 2021. Se realizó una síntesis de la información científica disponible en Medline, Pubmed, Cochrane, Scielo,Redalyc y Google Scholar.
Resultados: fueron identificados 37 textos y se estableció una categorización de análisis en 4 grupos: una posible reacción psicógena masiva, una posible reacción adversa a la vacuna, la necesidad de ampliar el enfoque epistemológico para comprender el fenómeno y una controversia en el campo científico colombiano.
Conclusiones: la revisión evidencia que la aplicación de la vacuna contra el VPH generó un problema de salud pública cuya naturaleza sigue siendo objeto de controversia, debido a una dificultad para identificar un diagnóstico etiológico de los síntomas de las afectadasIntroduction: in 2014 hundreds of teenage women in the rural municipality of El Carmen de Bolivar (Colombia)
experienced strange symptoms after being vaccinated with Gardasil, one of the vaccines against Human Papillomavirus
(HPV). Health authorities did not find a causal link between the vaccination and the symptoms, so they attributed
the phenomenon to a possible massive psychogenic reaction. The families of those affected rejected this hypothesis.
The case revealed the existence of a controversy among the Colombian scientific community about the safety of
the vaccine. The persistence over time of the health problem and its massive nature influenced a drastic decline in
vaccination coverage, and the Constitutional Court ruled in 2017 on the mandatory use of informed consent during
the vaccination procedure.
Methodology: an updated comprehensive narrative review of the literature published between 2014 and 2021 is
presented. A synthesis of the scientific information available in Medline, Pubmed, Cochrane, Scielo, Redalyc and
Google Scholar was performed.Introdução: em 2014, centenas de mulheres adolescentes do município rural de El Carmen de Bolívar, Colômbia,
experimentaram estranhos sintomas após serem vacinadas com Gardasil, uma das vacinas contra o vírus do papiloma
humano (HPV, por sua sigla em inglês). As autoridades sanitárias não encontraram vínculo causal entre a vacinação
e os sintomas, portanto atribuíram o fenômeno a uma possível reação psicogênica massiva. As famílias das afetadas
rejeitaram essa hipótese. O caso revelou a existência de uma controvérsia na comunidade científica colombiana
sobre a segurança da vacina. A persistência no tempo do problema de saúde e seu caráter massivo influenciaram na
drástica diminuição da cobertura dessa vacinação, e a Corte Constitucional decidiu, em 2017, o uso obrigatório do
consentimento informado durante o procedimento de vacinação.
Metodologia: é apresentada uma revisão narrativa de caráter integral atualizada sobre a literatura publicada entre
2014 e 2021. Foi realizada uma síntese da informação científica disponível em Medline, PubMed, Cochrane, SciELO,
Redalyc e Google Scholar.Universidad Tecnológica de BolívarIntroducción
Metodología
Resultados
Conclusiones
Referencia
Study of the properties of a composite material Fe78Si9B13 / GNP in an epoxy matrix
No full textThis study investigates the properties of a composite material obtained by mixing Fe78Si9B13 metallic powders (at %) with graphene nanoplates (GNP) in an epoxy matrix. Four composite types were created with GNP weight proportions of 0%, 0.5%, 1.0%, and 1.5%. The composites were embedded in transparent epoxy with weight proportions of 10%, 15%, and 20%, and then filled into 7 x 20 mm cylindrical probes. Twelve samples were prepared, and another 12 samples were subjected to a longitudinal magnetic field of 1 kG. All samples were tested with a Universal Testing Machine (Model WDW 10E) up to a maximum force of 20 kN. The experiment recorded deformation (ΔH) vs. charge force. Most samples showed a maximum compression resistance of 390 MPa, except for a few that did not exceed 100 MPa. The magnetically oriented samples showed a greater elastic limit in the range of 200 to 270 MPa. Optical microscopy was used to observe the ordering of the particles after the application of the magnetic field. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction were used to characterize the structure of the composite components. A vibrating sample magnetometer (VSM) was used to characterize the magnetic behavior of the metallic powders in the composite
Improving skin color accuracy in DLP-based 3D reconstruction
No full textColor accuracy is crucial in several domains such as biomedical imaging, cosmetics, and multimedia. Digital Light Processing (DLP) with LEDs has increasingly become a popular lighting source in 3D scanning systems. Although DLP provides advantages in 3D reconstruction, it poses challenges in maintaining color accuracy. Our research focused on using hybrid lighting to improve the color accuracy of DLP-based 3D sensing systems. We developed an empirical dataset featuring skin tones captured under multiple lighting environments, including variations in indoor ambient lighting. Through qualitative and quantitative evaluations of color differences, we conclude that including auxiliary lighting with DLP is beneficial for color accuracy, particularly in biomedical imaging and other applications in which color accuracy is essential