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Green hydrogen is gaining increasing attention as a key component of the global energy transition towards a more sustainable industry. Chile, with its vast renewable energy potential, is well positioned to become a major producer and exporter of green hydrogen. In this context, this paper explores the prospects for green hydrogen production and use in Chile. The perspectives presented in this study are primarily based on a compilation of government reports and data from the scientific literature, which primarily offer a theoretical perspective on the efficiency and cost of hydrogen production. To address the need for experimental data, an ongoing experimental project was initiated in March 2023. This project aims to assess the efficiency of hydrogen production and consumption in the Atacama Desert through the deployment of a mobile on-site laboratory for hydrogen generation. The facility is mainly composed by solar panels, electrolyzers, fuel cells, and a battery bank, and it moves through the Atacama Desert in Chile at different altitudes, from the sea level, to measure the efficiency of hydrogen generation through the energy approach. The challenges and opportunities in Chile for developing a robust green hydrogen economy are also analyzed. According to the results, Chile has remarkable renewable energy resources, particularly in solar and wind power, that could be harnessed to produce green hydrogen. Chile has also established a supportive policy framework that promotes the development of renewable energy and the adoption of green hydrogen technologies. However, there are challenges that need to be addressed, such as the high capital costs of green hydrogen production and the need for supportive infrastructure. Despite these challenges, we argue that Chile has the potential to become a leading producer and exporter of green hydrogen or derivatives such as ammonia or methanol. The country’s strategic location, political stability, and strong commitment to renewable energy provide a favorable environment for the development of a green hydrogen industry. The growing demand for clean energy and the increasing interest in decarbonization present significant opportunities for Chile to capitalize on its renewable energy resources and become a major player in the global green hydrogen market.

Este trabajo presenta un reporte preliminar de una plataforma para facilitar a alumnos, docentes e investigadores el acceso a clusters HPC a costos accesibles utilizando recursos existentes en las instituciones donde desempeñan sus actividades. Los laboratorios de informática de las universidades constituyen un reservorio de potencia de procesamiento. Estos pueden ser utilizados para conformar un cluster de cálculo de alto desempeño en los horarios que no se encuentran ocupados. De esta manera se puede al mismo tiempo reducir los costos de poseer un cluster HPC, ampliar el abanico de servicios y posibilidades que la institución brinda a sus miembros y aumentar la utilización de los laboratorios mejorando su amortización y por ende justificando mejor la inversión.

La Programación Genética (PG) es un conjunto de técnicas de computación evolutiva basadas en Algoritmos Genéticos, que permiten resolver problemas mediante la generación automática de programas. La PG ha demostrado ser un método eficiente para encontrar soluciones a una gran variedad de problemas donde se cuenta con una función objetivo o tarea a realizar. Sin embargo, una de las principales dificultades que presenta es la exploración y optimización de constantes numéricas (o parámetros). Este trabajo se enfoca en la investigación e implementación de distintos métodos para la optimización de dichas constantes, utilizando un framework de Tree-GP. Se eligió la Regresión Simbólica como aplicación debido a la clara necesidad de encontrar constantes precisas. Los métodos fueron probados en un conjunto de benchmarks, y se determinó que la herramienta logra buenos resultados, pero a medida que crece la complejidad del problema la tasa de éxitos disminuye y el costo computacional se incrementa considerablemente.

Low back pain is the leading cause of disability in the world, with a significant socio-economic impact. Deep dry needling is effective in the treatment of this pain, and it is one of the techniques preferred by physiotherapists. In this field, the use of ultrasound provides information of interest such as length, thickness, diameter, cross-sectional area, or muscle volume, among others. Objective: To find out whether the tissue changes (thickness, histogram, and contraction rate) that occur in the lumbar multifidus after application of the deep dry needle are related to changes in the pain and the disability of the patient. Design: Randomized, double-blind, parallel-group clinical trial. Setting: University of Alcalá, Department of Physiotherapy. Subjects: 21 voluntary patients (women and men) with non-specific low-back pain aged 18–65 years. Intervention: Patients were randomly divided into two groups. One group received dry needling and the other group a dry needling placebo. Initial post-needling and one week post-needling assessments were performed by a therapist blinded to the intervention. Variables: Lumbar multifidus thickness measured by RUSI, contraction time measured by M-mode, histograms measured by image analysis, muscle area, pain measured by VAS, pressure pain threshold measured by pressure algometer, and disability measured by Roland–Morris questionnaire. Conclusions: The contraction speed, resting thickness, and pain demonstrated significant differences within each group, but not between groups. There were significant differences in contraction ratio and in PPT between groups. There was excellent intra-examiner reliability in image collection for histogram analysis. Histogram analysis showed no significant differences between groups and measurements, neither for the parameters nor for the parameters combined with the outcome variables. A robust method for the image texture analyses in future histogram muscle analyses has been performed.

El objetivo principal de este proyecto fue desarrollar correlaciones para determinar el potencial a licuefacción de depósitos de arenas sueltas empleando el ensayo de penetración estática de piezocono CPTu; para ello fue necesario determinar el comportamiento de ensayos (CPTu) en la cámara de calibración (CC) del Laboratorio de Mecánica de Suelos y Rocas (IBF) en el Instituto Tecnológico de Karlruhe, además determinar la resistencia a licuefacción por medio de ensayos triaxiales cíclicos no drenados para muestras de arena, plantear una correlación entre la densidad relativa de almacenamiento (ID) de la muestra, la resistencia de punta (qc) del CPTu y la resistencia al flujo (CRR) de los ensayos triaxiales y por último comparar la correlación experimental obtenida con correlaciones existentes de la literatura. Con este proyecto se concluyó que en la región de bajas densidades de almacenamiento y bajas resistencias en punta una buena similitud, esto al comparar las correlaciones para los materiales experimentales estudiados por el IBF con correlaciones provenientes de la literatura. Ahora bien, para densidades altas y, por lo tanto, mayores resistencias en punta, las curvas de correlación para los materiales experimentales fueron más planas que en referencias bibliográficas; en otras palabras, la resistencia a licuefacción de los materiales experimentales en esta área es menor de lo que habrían predicho las curvas de la literatura. Así pues, no es posible aplicar directamente los resultados de este proyecto a otros sitios de estudio; ya que los materiales de las correlaciones realizadas (Kali4) y otros suelos difieren en aspectos como la mineralogía (criterios geológicos), la granulometría y la forma de partícula (criterios de composición); los cuales influyen sobre la susceptibilidad a la licuación.

With an elevation of 1000 m above sea level, once the coastal mountain range is crossed, the Atacama Desert receives the highest levels of solar radiation in the world. Global horizontal irradiations over 2500 kWh/(m2 year) and a cloudiness index below 3% were determined. However, this index rises to 45% in the coastal area, where the influence of the Pacific Ocean exists with a large presence of marine aerosols. It is on the coastal area that residential photovoltaic (PV) applications are concentrated. This work presents a study of the soiling impact on PV modules at the coastline of Atacama Desert. The current–voltage characteristics of two multicrystalline PV modules exposed to outdoor conditions were compared, while one of them was cleaned daily. Asymptotic behavior was observed in the accumulated surface dust density, over 6 months. This behavior was explained by the fact that as the glass became soiled, the probability of glass-to-particle interaction decreased in favor of a more likely particle-to-particle interaction. The surface dust density was at most 0.17 mg·cm−2 per month. Dust on the module led to current losses in the range of 19% after four months, which in turn produced a reduction of 13.5%rel in efficiency.

This work aimed to study the effects of static magnetic fields (SMFs) on cell cultures. A glass flask was filled with a liquid medium, which was surrounded by permanent magnets. Air was introduced through a tube to inject bubbles. Two magnet configurations, north and south, were used as perturbation. Scenedesmus obliquus and Nannochloropsis gaditana, growing in Medium 1 and 2, were subjected to the bubbly flow and SMFs. Differences between media were mainly due to conductivity (0.09 S/m for Medium 1 and 4.3 S/m for Medium 2). Joule dissipation ( P ) increased with the magnetic flux density ( B 0 ), being 4 orders of magnitude higher in Medium 2 than in 1. Conversely, the time constant ( τ P ) depended on B 0 , being nearly constant for Medium 1 and decreasing at 449 s/T for Medium 2. Dissipation occurred with the same τ P (235 s) in Medium 1 and 2 at B 0 = 0.5 T. In Species 1, the SMF effect was inhibitory. For Species 2, a higher enzymatic activity was observed. For superoxide dismutase, the relative difference was 78% with the north and 115% with the south configuration compared to the control values. For the catalase, differences of 29% with the north and 23% with the south configuration compared to control condition were obtained.

This paper presents the design, implementation and evaluation of a miniaturized Rat-race hybrid implemented in substrate CER-60 with microstrip transmission lines in a novel space-filling curve. This circuit is the main research's result of the project PS 3206funded by the Pontificia Universidad Javeriana. The hybrid achieves a miniaturization of 73 %, it operates in the 2.4 GHz ISM band, with an optimum operating frequency 2.56 GHz and a fractional band width of17.15%.