Browsing by Subject "13 Acción por el clima"

We have conducted an entropy analysis in Alaska, a seismic-rich region in a subduction zone that exhibits a nontrivial behavior: the subduction arc alters the seismic activity from the eastern zone to the western zone, demonstrating a decrease in activity along the subduction. We analyze this zone through the Tsallis entropy and the mutability (or dynamic entropy) for the first time. Considering 13 870 seismic events after appropriate filtering, we analyzed a data set for the selected Alaska zone between 2000 and 2023. We have found agreement between the results for the two entropies. We have followed the value of the q parameter of the Tsallis entropy (Sq) finding values between 1.70 and 1.85, in concordance with values found in other seismic regions of the planet. The values of Sq decrease slightly over time but show a broad increase before the major earthquakes. Just opposite to Tsallis entropy, mutability shows a tendency to decrease prior to the major earthquakes. We used the simpler mutability method to further analyze this zone upon dividing the region into four subzones. The results show how mutability can identify the seismic activity in each zone. This study shows how an entropy approach can shed light on understanding the seismicity in subduction zones.

This article presents a predictive control strategy to control a photovoltaic plant based on bifacial photovoltaic (BPV) panels connected to the electrical grid through a three-phase neutral point clamped (NPC) power converter. Electricity generation plants based on nonconventional renewable energies are affected by the availability of the natural resource and grid changes. To achieve optimal use of natural resources and equipment, BPV cells must operate at the maximum power point and the currents injected into a grid must be in phase with the voltages. Due to the high number of states, one important drawback of conventional predictive control in the NPC converter is its computational burden. The proposed controller avoids the use of a cost function and can achieve the same control objectives with only 20% of the computational cost of the conventional strategy. To achieve this reduction the proposed strategy exploits the operating area of the converter, separating the possible voltages in hexagons, which results in a shape like a honeycomb. Simulation and experimental results show the feasibility of the proposed method in different operating conditions.

First-ever measurements of the turbulent kinetic energy (TKE) dissipation rate in the northeastern Strait of Magellan (Segunda Angostura region), obtained in March 2019, are presented. During the microstructure measurements, the magnitude of the reversing tidal current ranged between 0.8 and 1.2 m s⁻¹. The probability distribution of the TKE dissipation rate in the water interior above the bottom boundary layer was lognormal, with a high median value of ε_MS(med) = 1.2 × 10⁻⁶ W kg⁻¹. Strong vertical shear, ranging from 1 × 10⁻² to 2 × 10⁻² s⁻¹, in the weakly stratified water interior resulted in a subcritical gradient Richardson number (Ri < 10⁻¹–10⁻²). In the bottom boundary layer (BBL), both the vertical shear and the TKE dissipation rate decreased exponentially with distance from the seafloor (ξ), leading to a turbulent regime characterized by an eddy viscosity K_M ≈ 10⁻³ m² s⁻¹. This parameter varied with time and location, while remaining independent of the vertical coordinate in the upper part of the BBL (for ξ ≳ 2 m above the bottom).

Los edificios tradicionales de entramado de madera representan una parte importante del patrimonio arquitectónico chileno. En particular, la tipología conocida como tabique-adobillo se propagó por localidades como Valparaíso, Santiago, Coquimbo, y el campamento minero Sewell. En este sistema las uniones carpinteras son cruciales para dar estabilidad a la estructura, ya que son las encargadas de transmitir las cargas entre sus elementos y disipar la energía durante un sismo, lo que las vuelve vulnerables a daños por sobrecarga y a la separación de las piezas. Reforzar las uniones permite mejorar la capacidad y estabilidad de las estructuras, previniendo dicha separación. Esta investigación propone una metodología semicuantitativa para el diseño de soluciones de reforzamiento de uniones carpinteras, integrando la teoría de resolución de problemas de inventiva y los principios modernos de rehabilitación. La metodología propuesta se aplica para diseñar dos refuerzos para la unión caja y espiga, característica de la tipología tabique-adobillo.