Aplicación de optimización multiobjetivo con algoritmos genéticos a un problema de electrificación rural.

Se presenta una aplicación de Algoritmos Genéticos como una herramienta para resolver problemas de optimización multiobjetivo. Los problemas que consideran la optimización de múltiples objetivos requieren consideraciones adicionales bastante complejas en comparación con los problemas de optimización que incluyen un solo objetivo. El uso de algoritmos genéticos permite soluciones más eficaces en cierto tipo de problemas combinatorios multiobjietivo. Este trabajo consiste de la aplicación de algoritmos genéticos para resolver un problema de expansión en electrificación rural en el que se consideraron varios objetivos. Finalmente se presentan algunas conclusiones y recomendacioes

Development of a didactic bench for the verification of the quality parameters of cylindrical gear transmissions

Las Transmisiones Dentadas han permitido el desarrollo de productos cada vez más compactos, confiables y versátiles. Esto se debe en gran medida a que la comunicación y adecuación de la potencia mecánica mediante engranes tiene unas características muy especiales como la casi ausencia de deslizamiento; la elevada capacidad de potencia con masas y dimensiones relativamente bajos, la elevada vida útil y fiabilidad, el elevado rendimiento. Es por esto, que vemos muy necesario para los futuros diseñadores mecánicos, el que reciban una formación amplia relacionada con la concepción, análisis y control de calidad de los engranajes apoyada desde la propuesta pedagógica que se presentará en este artículo, en el que se resumen los criterios de cálculo y las nociones de errores y calidad de las trasmisiones dentadas conforme con la normativa internacional ISO-AGMA, así como la descripción de un montaje para la verificación de los errores de calidad.The Gear Transmissions have allowed the development of increasingly compact, reliable and versatile products. This is largely due to the fact that the communication and adaptation of the mechanical power by means of gears has very special characteristics such as the almost no slippage; the high power capacity with relatively low masses and dimensions, the long service life and reliability, the high performance. This is why we see that it is very necessary for future mechanical designers, who receive extensive training related to the conception, analysis and quality control of the gears supported by the pedagogical proposal that will be presented in this article, which summarizes the calculation criteria and the notions of errors and quality of the toothed transmissions in accordance with international ISO-AGMA standards, as well as the description of an assembly for the verification of quality errors

Generalized synchronization in relay systems with instantaneous coupling

We demonstrate the existence of generalized synchronization in systems that act as mediators between two dynamical units that, in turn, show complete synchronization with each other. These are the so-called relay systems. Specifically, we analyze the Lyapunov spectrum of the full system to elucidate when complete and generalized synchronization appear. We show that once a critical coupling strength is achieved, complete synchronization emerges between the systems to be synchronized, and at the same point, generalized synchronization with the relay system also arises. Next, we use two nonlinear measures based on the distance between phase-space neighbors to quantify the generalized synchronization in discretized time series. Finally, we experimentally show the robustness of the phenomenon and of the theoretical tools here proposed to characterize it

Predicción del precio de la energía eléctrica con un modelo de redes neuronales y usando variables macroclimáticas.

Se hace una breve descripción de las características del Precio de la Energía en Bolsa en Colombia y de las variables que pueden incidir en su formación. Debido a la naturaleza empírica de los diversos parámetros, que hacen parte del diseño de las Redes Neuronales se realizan experimentos con diversos casos, en los cuales se varían algunos parámetros y se llega al diseño de una Red Neuronal que modela adecuadamente el Precio de la Energía. Las variables finalmente seleccionadas para modelar el Precio de la Energía en Bolsa son el embalse ofertable agregado, los aportes agregados al sistema y las anomalías de temperatura superficial del mar en la región Niño 3-4 del Océano Pacifico. Se presentan algunos resultados seguidos de algunas conclusione

The combustion engine as a mechatronic object in mechanical technology undergraduate curriculum

Internal combustion engines, ICE, have evolved to mechatronic systems. They consist of thermodynamic processes, electromechanic, hydraulic or pneumatic actuators, electronic sensors and one or more digital control units. This paper is aimed at presenting the modern combustion engines from a Mechatronics perspective to be taken into account in the course on Mechatronics in the “Mechanical Technology curriculum” at the Universidad Tecnológica de Pereira. The Laboratory of Mechatronics is under development and the course methodology seeks to use some machines, among which the internal combustion engine is listed. It is described the broad concept of mechatronics, the composition of modern ICE engines; two engine test benche sdeveloped as teaching tools for testing and control of ICE are presented

The combustion engine as a mechatronic object in mechanical technology undergraduate curriculum

Internal combustion engines, ICE, have evolved to mechatronic systems. They consist of thermodynamic processes, electromechanic, hydraulic or pneumatic actuators, electronic sensors and one or more digital control units. This paper is aimed at presenting the modern combustion engines from a Mechatronics perspective to be taken into account in the course on Mechatronics in the “Mechanical Technology curriculum” at the Universidad Tecnológica de Pereira. The Laboratory of Mechatronics is under development and the course methodology seeks to use some machines, among which the internal combustion engine is listed. It is described the broad concept of mechatronics, the composition of modern ICE engines; two engine test benche sdeveloped as teaching tools for testing and control of ICE are presented

Guía de seguridad industrial para la manipulación, almacenamiento y transporte de sustancias y productos químicos controlados.

La resolución 0001 de 2015 establece el registro de sustancias y productos químicos controlados por la Dirección Nacional de Antinarcóticos, en dicha resolución se proponen todos los requerimientos que deben cumplir las empresas que utilizan este tipo de sustancias, sin embargo, no se presentan claramente medidas de prevención de accidentes por su uso, almacenamiento y transporte. Teniendo en cuenta esta necesidad surge la idea de realizar una guía que facilite y reúna la información en cuanto al almacenamiento, manejo y transporte de sustancias y productos químicos controlados, puesto que cada día se deben adoptar métodos que mejoren las condiciones de trabajo de las personas y mitigue la exposición de riesgo que se puedan presentar. En el contenido de esta guía se plantean inicialmente los peligros relacionados con seguridad industrial que pueden afectar al trabajador, a continuación se propone una metodología para el adecuado almacenamiento, posteriormente se plantean recomendaciones para la manipulación de las sustancias, para finalmente proponer diversas actividades lúdicas para el fortalecimiento del aprendizaje temático

Health impacts of a randomized biomass cookstove intervention in northern Ghana

Background: Household air pollution (HAP) from cooking with solid fuels has adverse health effects. REACCTING (Research on Emissions, Air quality, Climate, and Cooking Technologies in Northern Ghana) was a randomized cookstove intervention study that aimed to determine the effects of two types of "improved" biomass cookstoves on health using self-reported health symptoms and biomarkers of systemic inflammation from dried blood spots for female adult cooks and children, and anthropometric growth measures for children only. Methods: Two hundred rural households were randomized into four different cookstove groups. Surveys and health measurements were conducted at four time points over a two-year period. Chi-square tests were conducted to determine differences in self-reported health outcomes. Linear mixed models were used to assess the effect of the stoves on inflammation biomarkers in adults and children, and to assess the z-score deviance for the anthropometric data for children. Results: We find some evidence that two biomarkers of oxidative stress and inflammation, serum amyloid A and C-reactive protein, decreased among adult primary cooks in the intervention groups relative to the control group. We do not find detectable impacts for any of the anthropometry variables or self-reported health. Conclusions: Overall, we conclude that the REACCTING intervention did not substantially improve the health outcomes examined here, likely due to continued use of traditional stoves, lack of evidence of particulate matter emissions reductions from "improved" stoves, and mixed results for HAP exposure reductions. Clinical trial registry: ClinicalTrials.gov (National Institutes of Health); Trial Registration Number: NCT04633135 ; Date of Registration: 11 November 2020 - Retrospectively registered. URL: https://clinicaltrials.gov/ct2/show/NCT04633135?term=NCT04633135&amp;draw=2&amp;rank=1. </div

Evaluating the Effects of Access to Air Quality Data on Household Air Pollution and Exposure-An Interrupted Time Series Experimental Study in Rwanda

In Sub-Saharan Africa, around 80% of residential energy demand is for cooking, with over 760 million people without access to clean cooking fuels and stoves. Particulate matter smaller than 2.5 microns (PM2.5) is a significant pollutant from biomass burning and is linked to respiratory and cardiovascular diseases, as well as adverse pregnancy outcomes. Energy poverty further reinforces gender disparities, keeps children from schools, causes environmental degradation, and interferes with social and economic development. Lack of access to and inadequate adoption of clean cooking stoves and fuels are key barriers to improved air quality. This paper presents a field experiment nested within a large-scale health efficacy trial. The aim of the experiment was to evaluate the effects of access to air quality data and dynamic feedback on indoor air pollution (IAP) and personal exposure. Ninety households in Rwanda were enrolled and provided with an air quality sensor and feedback device, which measured real-time indoor air quality as PM2.5 for sixteen weeks. After six weeks, PM2.5 levels were provided dynamically to households through a display and an auditory alarm. We examined the effects of receiving this feedback on IAP and personal exposure. While access to air quality data did not, in aggregate, improve PM2.5 levels, we did observe several promising correlations worthy of further investigation. The associations between personal exposure or rainfall and increased PM2.5 were reduced after households had access to air quality data. We hypothesized that the behavior changes required to observe these effects&mdash;opening doors and windows and moving away from cooking sources&mdash;are easy and immediate, in contrast to the costs and complex logistics of entirely eliminating biomass cooking. The types of behavior changes that would directly impact household air pollution and exposure require more than just awareness and willingness to act.</p