Universidad Tecnológica de Bolívar
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Hybrid lighting enhances color accuracy in DLP-based 3D imaging
No full textColor accuracy is of immense importance in various fields, including biomedical applications, cosmetics, and multimedia. Achieving precise color measurements using diverse lighting sources is a persistent challenge. Recent advancements have resulted in the integration of LED-based Digital Light Processing (DLP) technology into many scanning devices for 3D imaging, often serving as the primary lighting source. However, such setups are susceptible to color-accuracy issues. Our study delves into DLP-based 3D imaging, specifically focusing on the use of hybrid lighting to enhance color accuracy. We presented an empirical dataset containing skin tone patches captured under various lighting conditions, including combinations and variations in indoor ambient light. A comprehensive qualitative and quantitative analysis of color differences (∆E 00 ) across the dataset was performed. Our results support the integration of DLP technology with supplementary light sources to achieve optimal color correction outcomes, particularly in skin tone reproduction, which has significant implications for biomedical image analysis and other color-critical applications
Aguas turbias no son espejos
No full text“Aguas turbias no son espejos” que relata desde la visión de las comunidades las afectaciones que han sufrido a causa de la presencia de monocultivos y la agroindustria en sus territorios y cómo esto ha vulnerado sus derechos bioculturales. El documental se realizó en los corregimientos de comunidades afro y campesinas en San José del Playón y La Suprema, en los Montes de María desde el mes de marzo del año 2021 hasta el mes julio de año 2022.
En el proyecto estuvieron vinculados además de la Universidad Tecnológica de Bolívar, el Instituto de Políticas Públicas, Regional y de Gobierno - IPREG de la Universidad de Cartagena, la Universidad de San Buenaventura Cartagena en la producción general, científica y académica del proyecto.Universidad de Cartagena; Universidad Tecnológica de Bolívar; Universidad San Buenaventura, sede Cartagen
Design of PV fed single-switch transformer less topology powered electric vehicle
No full textAs a result of an increase in the availability of resources that were not harmful to the environment, solar energy applications shot to popularity. Photovoltaic cells power systems that necessitate DC-DC converters because of their low voltage output. This investigation uses photovoltaic cells (PV) to power a high-voltage gain design with just one switch and no transformer. The proposed circuit utilizes a single regulated switch, which contributes to a reduction in switching losses. It requires fundamental pulse regulation. The network used a switched capacitor cell and an LC passive filter to provide an accurate step-up voltage. We can obtain the equation for the step-up voltage gain from the steady-state continuous conduction mode. The equations used for the theoretical design of converters include energy. To show that the topology is comparable with other modern converters that have been published, a comparison was made between it and other converters. In order to validate the converter's effectiveness, simulations built in MATLAB and Simulink are used
HyTra: Hyperclass Transformer for WiFi Fingerprinting-based Indoor Localization
No full textThe emerging demand for a variety of novel Location-based Services (LBS) by consumers and industrial users is driven by the rapid and extensive proliferation of mobile smart devices. Sensors embedded in smart devices or machines provide wireless connectivity and Global Positioning System (GPS) capability, and are co-utilized to acquire location-linked data which are algorithmically transformed into reliable and accurate location estimates. GPS is a mature and reliable technology for outdoor localization but indoor localization in a complex multi-storey building environment remains challenging due to fluctuations in wireless signal strength arising from multipath fading. Location-linked data from wireless access points (WAPs) such as received signal strength (RSS) are acquired as numerical sequences. By conceptualizing a fixed order sequence of WAP measurements as a sentence where the RSS from each WAP are words, we may leverage on recent advances in artificial intelligence for natural language processing (NLP) to enhance localization accuracy and improve robustness against signal fluctuations. We propose the hyper-class Transformer (HyTra), an encoder-only Transformer neural network which learns the relative positions of wireless access points (WAPs) through multiple learnable embeddings. We propose a second network, HyTra-HF, which improves upon HyTra by applying a hierarchical relationship between location classes. We test our proposed networks on public and private datasets varying in sizes. HyTra-HF outperforms existing deep learning solutions by obtaining 96.7\% accuracy for the floor classification task on the UJIIndoorloc dataset. HyTra-HF is amenable to deep model compression and achieves accuracy of 95.95\% with over ten-fold reduction in model size using Sparsity Aware Orthogonal (SAO) initialization and has the best-in-class accuracy for the sparse model
Capacidades para el acceso a la educación superior en clave de desarrollo humano en Cartagena de indias: la experiencia de fundación Adomi (2013-2020)
No full textEn Cartagena de Indias acceder a la educación superior representa un desafío debido a que la oferta académica de las universidades públicas es insuficiente, y porque las universidades privadas son muy costosas. Según datos de Cartagena Cómo Vamos, en su “Informe de calidad de vida” (2021, p. 44) en la ciudad de Cartagena “12.068 estudiantes se matricularon en grado 11 en las instituciones educativas de Cartagena, pero solo ingresaron a la educación superior 5.108 (solo el 42% ingresó a la educación superior)”. Antes de la pandemia causada por el Covid-19, las universidades públicas en la ciudad, que son las más asequibles, seleccionaban a sus nuevos estudiantes a partir de la aplicación de un examen de admisión presencial: siguiendo la lógica de “el que lo ganó, lo ganó; y el que no, no (hasta donde alcancen los cupos) ”. Pero, a partir de la pandemia, como estaban prohibidas las aglomeraciones , la selección de esos nuevos estudiantes (hasta la fecha de elaboración de esta investigación) se ha realizado con el puntaje global obtenido en las pruebas Saber 11. Así pues, tanto en el modelo de admisión anterior como en el nuevo, quienes no logren una calificación numérica determinada por un examen externo a su preparación colegial, sencillamente no podrán acceder a la educación superior. Dicho proceso de selección pone en evidencia las brechas de desigualdad social presentes en Cartagena, porque compiten estudiantes de escasos recursos con estudiantes de clase media y alta en condiciones de igualdad, más no de equidad. En ese orden de ideas, el presente es un proyecto de investigación que se propuso la sistematización de la experiencia de Fundación ADOMI creando capacidades que facilitan el acceso a la educación superior de los jóvenes de escasos recursos en Cartagena de Indias (entre 2013 y 2020). Se utilizó una metodología cualitativa, de paradigma interpretativo con enfoque etnometodológico. Para ello, se recopiló la información a través del análisis de documentos y entrevistas semiestructuradas; se estableció contacto con la organización revisando su cronología (historia), su filosofía (misión y visión) y su modelo de negocio; además de realizar un diseño muestral acerca del perfil de sus beneficiarios, clientes y aliados.Magister en Desarrollo y CulturaMaestrí
Spurring or Blurring Journalism & Mass Communication Quarterly 1–32 © 2024 AEJMC Professional Standards? The Role of Digital Technology in Implementing Journalistic Role Ideals in Contemporary Newsrooms
No full textThis study examines the perceived relevance and implementation of competing normative ideals in journalism in times of increasing use of digital technology in newsrooms. Based on survey and content analysis data from 37 countries, we found a small positive relationship between the use of digital research tools and “watchdog” performance. However, a stronger and negative relationship emerged between the use of digital audience analytics and the performance of “watchdog” and “civic” roles, leading to an overall increase in conception–performance gaps on both roles. Moreover, journalists’ use of digital community tools was more strongly and positively associated with “infotainment” and “interventionism.”Este estudio examina la relevancia percibida y la aplicación de ideales normativos contrapuestos en el periodismo en los tiempos del creciente uso de la tecnología digital en las salas de redacción. Basándonos en datos de encuesta y análisis de contenido de 37 países, encontramos una pequeña relación positiva entre el uso de herramientas de investigación digitales y el desempeño de los “perros guardianes”. Sin embargo, surgió una relación más fuerte y negativa entre el uso de análisis de audiencia digital y el desempeño de roles de “perro guardián” y “cívico”, llevando a un aumento general en las brechas concepción-desempeño en ambos roles. Además, el uso de herramientas de la comunidad digital por parte de los periodistas estaba más fuerte y positivamente asociado con el “infoentretenimiento” y el “intervencionismo”
Shear stress solutions for curved beams: a structural analysis approach
No full textThe shear stress on isotropic curved beams with compact sections and variable thickness is
investigated. Two new solutions, based on Cook’s proposal and the mechanics of materials approach,
were developed and validated using computational finite element models (FEM) for four typical
cross-sections (rectangular, circular, elliptical, and triangular) used in civil and mechanical structures,
constituting a novel approach to predicting shear stresses in curved beams. They predict better
results than other reported equations, are simpler and easier for engineers to use quickly, and join the
group of equations found using the theory of elasticity, thereby expanding the field of knowledge.
The results reveal that both equations are suitable to predict the shear stress on a curved beam
with outer/inner radii ratios in the interval 1 < b/a ≤5 aspect ratios. There is a maximum relative
difference between the present solutions and finite element models of 8% within 1 < b/a ≤2, and a
maximum of 16% in 2 < b/a ≤5. Additionally, the neutral axis of the curved beam can be located
with the proposed solution and its position matches with that predicted by FEM. The displacement at
the top face of the end of the curved beam induces a difference in the shear stress results of 8.0%, 7.0%,
6.5%, and 2.9%, for the circular, rectangular, elliptical, and triangular cross-sections, respectively,
when a 3D FEM solution is considered. For small b/a ratios (near 1), the present solutions can be
reduced to Collignon’s formula
Possibilités de gestion des conflits grâce à l'intelligence artificielle dans les systèmes d'administration judiciaire d'Amérique latine
No full textLos sistemas de administración de justicia latinoamericanos se enmarcan en un contexto global cambiante, caracterizado por transformaciones dinámicas desde la tecnología y con el uso de la Inteligencia Artificial. Y aunque el ejercicio profesional del derecho ha estado un tanto al margen de la adopción de estos avances tecnológicos, resulta relevante analizar desde los debates iusteóricos las posibilidades para implementar la Inteligencia Artificial para la gestión de situaciones conflictivas que exigen gestión desde la labor judicial. Así, es posible considerar que la Inteligencia Artificial tiene cinco niveles de complejidad, iniciando por sistemas reactivos y llegando a modelos holísticos que aún no han sido materializados. En consecuencia, en las condiciones actuales de la tecnología, la Inteligencia Artificial estaría en la capacidad de conocer, gestionar y decidir casos con bajos niveles de dificultad, mientras que los casos de complejidad avanzada aún requieren de la intervención humana. En este sentido, este artículo constituye un marco hermenéutico para entender cómo vincular la Inteligencia Artificial desde sus diferentes niveles en la gestión de casos con variados niveles de dificultad. Para ello se acoge un enfoque de investigación crítico, marcadamente cualitativo y fundamentado en revisión documental.Les systèmes d’administration de la justice latino-américains s’inscrivent dans un contexte mondial changeant, caractérisé par des transformations dynamiques basées sur la technologie et l’utilisation de l’intelligence artificielle. Et même si la pratique professionnelle du droit a été quelque peu en marge de l'adoption de ces avancées technologiques, il est pertinent d'analyser à partir de débats théoriques les possibilités de mise en œuvre de l'Intelligence Artificielle pour la gestion des situations conflictuelles qui nécessitent une gestion du travail judiciaire. Ainsi, il est possible de considérer que l’Intelligence Artificielle comporte cinq niveaux de complexité, commençant par des systèmes réactifs et atteignant des modèles holistiques qui ne se sont pas encore matérialisés. Par conséquent, dans les conditions technologiques actuelles, l’Intelligence Artificielle serait capable de connaître, gérer et décider des cas avec de faibles niveaux de difficulté, alors que les cas de complexité avancée nécessitent encore une intervention humaine. En ce sens, cet article constitue un cadre herméneutique pour comprendre comment relier l’Intelligence Artificielle à partir de ses différents niveaux dans la gestion de cas avec différents niveaux de difficulté. Pour y parvenir, une démarche de recherche critique est adoptée, résolument qualitative et fondée sur une revue documentaire.Os sistemas de administração de justiça latino-americanos estão enquadrados num contexto global em mudança, caracterizado por transformações dinâmicas baseadas na tecnologia e no uso da Inteligência Artificial. E embora o exercício profissional da advocacia tenha estado um tanto à margem da adoção desses avanços tecnológicos, é relevante analisar a partir de debates teóricos as possibilidades de implementação de Inteligência Artificial para a gestão de situações de conflito que exigem gestão do trabalho judicial. Assim, é possível considerar que a Inteligência Artificial possui cinco níveis de complexidade, começando pelos sistemas reativos e chegando aos modelos holísticos que ainda não foram materializados. Consequentemente, nas atuais condições da tecnologia, a Inteligência Artificial seria capaz de conhecer, gerir e decidir casos com baixos níveis de dificuldade, enquanto casos de complexidade avançada ainda requerem intervenção humana. Neste sentido, este artigo constitui um quadro hermenêutico para compreender como interligar a Inteligência Artificial dos seus diferentes níveis na gestão de casos com variados níveis de dificuldade. Para isso, adota-se uma abordagem de pesquisa crítica, marcadamente qualitativa e baseada na revisão documental.Latin American justice administration systems are framed in a changing global context, characterized by dynamic transformations based on technology and the use of Artificial Intelligence. And although the professional practice of law has been somewhat on the margins of the adoption of these technological advances, it is relevant to analyze from theoretical debates the possibilities for implementing Artificial Intelligence for the management of conflict situations that require management from judicial work. Thus, it is possible to consider that Artificial Intelligence has five levels of complexity, starting with reactive systems and reaching holistic models that have not yet been materialized. Consequently, under current technological conditions, Artificial Intelligence would be able to know, manage and decide cases with low levels of difficulty, while cases of advanced complexity still require human intervention. In this sense, this article constitutes a hermeneutical framework to understand how to link Artificial Intelligence from its different levels in the management of cases with varying levels of difficulty. To achieve this, a critical research approach is adopted, markedly qualitative and based on documentary review.Universidad Tecnológica de Bolívar1. INTRODUCCIÓN. 2. SITUACIONES QUE SON ANALIZADAS POR LA ADMINISTRACIÓN DE JUSTICIA DESDE LA PUGNA IUSTEÓRICA ENTRE EL FORMALISMO Y EL ANTIFORMALISMO 3. POSIBILIDADES PARA QUE LA INTELIGENCIA ARTIFICIAL GESTIONE LAS SITUACIONES IUSTEÓRICAMENTE DELIMITADAS DESDE LA ADMINISTRACIÓN DE JUSTICIA 4. CONCLUSIONES. REFERENCIA
Automated Photovoltaic Irrigation System for Crops in the Colombian Caribbean Region
No full textThe project presents a proposal for the design and implementation of an automated photovoltaic irrigation system for crops in the Caribbean region of Colombia. The main motivation is to address the challenges related to water use in agriculture and the lack of access to electricity in some rural areas. This system uses the principles of precision agriculture by collecting and processing real-time data on weather and soil conditions using a network of sensor nodes distributed throughout the crop area. As a solution, a solar-powered automated irrigation system based on a wireless sensor network (WSN) was designed to remotely monitor soil moisture and temperature. In the proposed system, relevant weather and soil parameters are collected by a wireless sensor network and transmitted to a base station. The base station processes the collected data and executes irrigation control algorithms to improve water use. The system is powered by solar energy, making it viable in areas without access to the electrical grid. The implementation of this automated and sustainable irrigation system not only contributes to improved agricultural productivity and water conservation, but also lays the groundwork for the adoption of precision agriculture practices in the Colombian Caribbean region. By combining innovative technologies such as sensor networks, IoT and renewable energy, this project represents a significant step towards more efficient, productive and environmentally friendly agriculture.Universidad Tecnológica de BolívarIngeniero ElectrónicoPregrad
Estimation of backbone model parameters for simulation of exposed column base plates
No full textAn approach is presented for the estimation of the parameters required to simulate the nonlinear monotonic (i.e., backbone) rotational response of Exposed-Column-Base-Plate (ECBP) connections subjected to moment and axial compression. A trilinear backbone curve is selected to represent the rotational response, defined by three deformation and two strength parameters; these properly represent the stiffness, strength, and ductility of the connections. This approach is accompanied by a tool to facilitate convenient estimation of the parameters. The approach is based on a combination of behavioral insights and physics-based models (for some parameters) as well as regression for other parameters, which are estimated from a dataset of eighty-four experiments on ECBP connections conducted over the last forty years in the United States, Europe, and Asia. Predictive equations are provided to estimate the various parameters defining the nonlinear response, and their efficacy is examined by comparing them with the test data; in addition, well-established techniques are implemented to avoid collinearity and the overfitting of regression models. The results show that the models presented in this work provide robust and accurate predictions for in-sample and out-of-sample data. Limitations are outlined.Fundación Carolina, Universidad Tecnológica de Bolívar, PCEM SA