Revistas UTB ( Universidad Tecnológica de Bolívar)
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Study of the properties of a composite material Fe78Si9B13 / GNP in an epoxy matrix
Full text linkThis 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
Technological prototype with artificial intelligence for military security in river environments
Full text linkMaritime and river security is one of the main concerns of military forces due to the large number of illicit activities that occur. Not to mention the extensive areas that must be monitored, and the weather conditions that can occur. Currently, technologies have become fundamental to leave aside manual surveillance for intelligent systems that allow remote sensing, traffic control, and object detection. Based on the aforementioned problems, the purpose of this research was to design a technological prototype with artificial vision based on an artificial intelligence model to detect water vessels and people in river environments as a support tool for military security. The prototype used at hardware level a Raspberry Pi 3 card and four pre-trained models based on R-CNN, YOLO, EfficientDet and SSD (single shot multibox). The best-performing model was the Mobilnet V2 SSD, with an mAP of 0.83 and an FPS of 5. Finally, this tool can contribute to strengthening the strategic, tactical, and operational capabilities of actors in the military intelligence sector, aimed at protecting sovereignty and territorial integrity to establish an environment of security in society
Automatic differential kinematics of serial manipulator robots through dual numbers
Full text linkDual Numbers are an extension of real numbers known for its capability of performing exact automatic differentiation of one-valued functions theoretically without error approximation. Also, Differential Kinematics of robots involves the computation of the Jacobian, which is a matrix of partial derivatives of the Forward Kinematic equations with respect to the robot’s joints. Thus, to perform the automatic calculation of the Jacobian matrix, this paper presents an extension of dual numbers composed of a scalar real part and a vector dual part, where the real part represents the angular value of the robot joint, and the dual part represents the direction of the corresponding partial derivative for each joint. The presented method was implemented in Matlab through Object Orientes Programming (OOP), and the results for calculating the Jacobian of the KUKA KR 500 robot model for 1000 random postures were subsequently compared in terms of execution time and Mean Squared Error (MSE) with other conventional methods: the geometric method, the symbolic method, and the finite difference method. The results showed a significant improvement in the computing time for calculating the Jacobian of the robotic model compared to the other methods, as well as a minimum MSE having as reference the numerical value of the symbolic calculations
Academic research contributions from Ibero-American countries to general knowledge, engineering, and computer science up to 2023 and COVID impact
Full text linkAlthough commonly, competitive intelligence analysis is applied to companies, where new investments and operation expenditures are considered along with changes in the market, competitive intelligence can be applied to different countries' academic research production, which impacts science, technology and innovation making a difference in their competitiveness. This work shows the academic research production for all areas of knowledge, and also specifically for engineering and computer science, from all the Ibero-American countries, based on the SCOPUS database from 2001 to 2023. The results show that based on the volume of their academic production, for an affordable analysis, the Ibero-American countries can be classified into three groups, considering an order of magnitude difference for each group. The leading group is composed of countries producing between 200,000 and about 2 million documents, the second group of countries producing between 20,000 and 200,000 documents, and the third group of countries producing between 2,000 and 20,000 documents. The COVID pandemic impacted all the countries which showed a decrease in annual production over the last two years. The results also show the priority areas of knowledge that these countries invest in and the main countries that they collaborate with. The behavior of production for engineering and computer science is like that of general production, but there are some specific internal factors for specific countries such as in the case of Brazil, the country in which production fell most dramatically, followed by Spain and Colombia. On the other hand, Peru and Ecuador show a high interest in engineering and computer science. This work offers a high value decision-making tool to leaders in academic research, the principals of research driven institutions and investors from industry in Ibero-America. The academic production is related to the size of the GDP and the percentage of the GDP invested by a country in research development and innovation
IOT Based Intelligent Energy Monitoring of Grid connected Hybrid systems and controlling of Loads using PLC
Full text linkNowadays IOT becoming popularize in all the application especially in the power system network for data monitoring from the Hybrid power distribution system. Because of easy adaptability of IOT technology, it find its place in data monitoring for the remote system and data can also be logged in the cloud server for analysis of the system under surveillance. By having data enabled IOT system, which will make the complete system smarter in terms of monitoring and analysis of the performance of the power distribution network. In these research paper, concept IOT technology for data monitoring of grid connected Hybrid system consist of PV source for the typical educational institute was developed and implemented in the campus. Apart from the data monitoring, controlling of the critical loads connected to this hybrid system was developed using Programmable Logic Controller (PLC). The MyQtt based cloud server was used to store the data pushed from the IOT device and user interactive mobile Application was developed using MIT inventor to monitor the data in the mobile itself, the command from the Mobile app was given to the PLC to control the loads. The energy data from the Multi-function energy meter (MFM) is pushed to PLC through gateway of Raspberry Pi. In this paper, Raspberry PI was used as IOT device and ILC 131 ETH PLC was used to control the loads. Performance of IOT device along with PLC was monitored for 3 months and results obtained were satisfactory
Descentralización y pobreza: Un análisis para la región Caribe colombiana
Full text linkThis study explores the relationship between fiscal decentralization and poverty at the spatial level in Colombian municipalities. We use data on both material and non-material deprivation (Multidimensional Poverty Index) and examine the dependence on transfer resources across 1,101 municipalities in Colombia in 2005 and 2018. For this purpose, we use the bivariate Moran's index for analysis. The findings reveal a distinct positive spatial clustering, highlighting the proximity between municipalities with high poverty levels and strong dependence on transfers. This clustering has intensified in recent years, particularly in the peripheral areas of the country, with a notable emphasis on the Colombian Caribbean region. Recommendations focus on strengthening tools to enhance the collection of key municipal taxes (property, and industry and commerce taxes). Additionally, there is a call for increased flexibility in the use of resources received through transfers, considering the fiscal and well-being heterogeneities of the territories.El presente estudio explora la relación existente a nivel espacial entre la descentralización fiscal y la pobreza en 1.101 municipios de Colombia, mediante el uso de datos que reflejan la privación de bienes materiales y no materiales (Índice de Pobreza Multidimensional, IPM) y la dependencia de los recursos de transferencias en dos años, 2005 y 2018. Se propone el uso del índice de Moran bivariado para llevar a cabo la investigación. Los resultados muestran una marcada agrupación espacial positiva y destacan la vecindad entre municipios con altos niveles de pobreza y una fuerte dependencia de las transferencias. Esta agrupación ha experimentado un aumento en magnitud en los años más recientes, particularmente en las zonas periféricas del país, con especial énfasis en la región Caribe. Las recomendaciones se dirigen al fortalecimiento de las herramientas que propician el recaudo de los principales tributos municipales (predial e industria y comercio) y a la mayor flexibilidad en el uso de los recursos recibidos por transferencias considerando las heterogeneidades fiscales y de bienestar de los territorios
Real-time hardware-in-loop system based validation of vehicle-grid interface for bidirectional power flow control
Full text linkIn the context of modern sustainable transportation technology, the terms Vehicle-to-Grid (V2G) and Grid-to-Vehicle (G2V) holds significant value. During V2G and G2V modes, vehicle and grid exchange power using various power converters to modulate the power for a sustainable electrical energy ecosystem. With V2G, the EVs can also perform the role of a peak power contributor, reserve power source, and an efficient system to improve power quality issues by working as power factor corrector, reactive power compensator, and active power filter, to name a few during the V2G mode. The on-board power converter in the vehicle, working as the charger for the battery, is the component required to facilitate the intended bidirectional power exchange between the vehicle and grid and also modulates the power as and when required. The modality for operating the onboard charger as a power exchange tool depends on the type of control strategy adopted as well as on the battery and grid parameters. In this paper, a bidirectional power converter (on-board converter) is introduced, which is controlled by adopting a d-q axis-based control strategy. The MATLAB/SIMULINK-based system simulation model is created, and the Hardware-in-Loop (HIL) tool Opal-RT 4510 is used to validate the simulation results on the intended hardware and real-time scenario. The control strategy, when integrated with the adopted model, contributes to enhancing the power-transferring capability of the converter, which is assessed using the simulation and subsequent HIL-based implementation. The paper also focuses on narrating the steps to implement the vehicle-grid interface using HIL and forming a generic reference model for a bidirectional power flow converter, such that it can be used for other circuits and its implementation in real-time scenarios
Advancing energy innovations: Reflections on 2024, prospects for 2025
Full text linkThis editorial reflects on key points in the energy transition during 2024, including renewable energy growth, advancements in energy storage, and the rise of electric mobility. It also introduces special sections featuring research from the 2023 IEEE Colombian Caribbean and ICARGET Conferences. Looking ahead to 2025, it highlights the transformative roles of artificial intelligence, green hydrogen, and smart cities in shaping a sustainable energy future, reaffirming the journal’s commitment to driving innovation and global energy progress
Risk assessment of electric power generation systems using modified jellyfish search algorithm
Full text linkAn electric utility's main goal is to fulfil the requirements and expectations of its customers by providing power. When there are uncertainties, like equipment failures, system reliability evaluation offers a framework to guarantee that the system will still function properly. A modified Jellyfish Search Algorithm (JFSA) has been proposed for estimation of Electric power generation system reliability indices. Particle Swarm Optimization (PSO), Genetic Algorithm (GA), and other modified versions of algorithms have been used in algorithms that use optimization methods for the assessment of reliability indices. Jelly Fish Search Algorithm has been used in power systems to find the economic load dispatch of generating units, for integration of Distributed Generation (DG) units, Maximum Power tracking of PV system and Optimal Power Flow solutions etc. However, JFSA has not been implemented for the evaluation of reliability indices for electric power generation system. In this context a modified JFSA algorithm is developed for evaluation of certain reliability indices such as Loss of Load Expectation (LOLE), and Expected Demand Not Supplied (EDNS), Loss of Load Probability (LOLP). The algorithm presented is implemented on two test system which are RBTS 6 bus system and IEEE 24 bus Reliability Test System. The Results obtained are compared for different models of Generation and Load and are analysed
El desempeño fiscal de Mompox a fines del período colonial, 1761 – 1807
Full text linkEn este documento se analizan los ingresos de la Caja Real de Mompox, el principal puerto fluvial del Caribe neogranadino, entre 1761 y 1807, usando fuentes provenientes del Archivo General de Indias. Los resultados indican que esta fue la quinta caja con mayor importancia económica en todo el Virreinato de Nueva Granada. El desglose por fuentes de ingreso muestra una actividad económica local impulsada por la presencia de una población con buenos ingresos, así como un crecido flujo de viajeros y personas que llegaban a comerciar allí. En el Caribe neogranadino solo Cartagena tenía mayor importancia demográfica y económica