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In recent years, the demand and requirement for renewable energy have significantly increased due to concerns regarding energy security and the climate crisis. This has led to a significant focus on wind power generation. As the deployment of wind turbines continues to rise, there is a growing need to assess their lifespan and improve their stability. Access to accurate load data is crucial for enhancing safety and conducting remaining life assessments of wind turbines. However, maintaining and ensuring the reliability of measurement systems for long-term load data accumulation, stability assessments, and residual life evaluations can be challenging. As a result, numerous studies have been conducted on load prediction for wind turbines. However, existing load prediction models based on 10 min statistical data cannot adequately capture the short-term load variations experienced by wind turbines. Therefore, it is essential to develop models capable of predicting load with a high temporal resolution to enhance reliability, especially with the increasing scale and development of floating wind turbines. In this paper, we developed prediction models with a 50 Hz resolution for the bending strain at the tower bottom of offshore wind turbines by combining SCADA data and acceleration data using machine learning techniques and analyzed the results. The load prediction models demonstrated high accuracy, with a mean absolute percentage error below 4%. [ABSTRACT FROM AUTHOR]

We report Chern insulating phases emerging from a single layer of layered chalcogenide CrSiTe3, a transition metal trichacogenides (TMTC) material, in the presence of charge doping. Due to strong hybridization with Te p orbitals, the spin-orbit coupling effect opens a finite band gap, leading to a nontrivial topology of the Cr eg conduction band manifold with higher Chern numbers. Our calculations show that quantum anomalous Hall effects can be realized by adding one electron in a formula unit cell of Cr2Si2Te6, equivalent to electron doping by 2.36 × 1014 cm−2 carrier density. Furthermore, the doping-induced anomalous Hall conductivity can be controlled by an external magnetic field via spin-orientation-dependent tuning of the spin-orbit coupling. In addition, we find distinct quantum anomalous Hall phases employing tight-binding model analysis, suggesting that CrSiTe3 can be a fascinating platform to realize Chern insulating systems with higher Chern numbers. [ABSTRACT FROM AUTHOR]

We investigate the electronic and magnetic structures of two-dimensional transition metal tri-chalcogenide CrSiTe3 and CrGeTe3 materials by carrying out first-principles calculations. The single-layer CrSiTe3 and CrGeTe3 are found to be a ferromagnetic insulator, where the presence of the strong dpσ-hybridization of Cr eg-Te p plays a crucial role for the ferromagnetic coupling between Cr ions. We observe that the bandgaps and the interlayer magnetic order vary notably depending on the magnitude of on-site Coulomb interaction U for Cr d electrons. The bandgaps are formed between the Cr eg conduction bands and the Te p valence bands for both CrSiTe3 and CrGeTe3 in the majority-spin channel. The dominant Te p antibonding character in the valence bands just below the Fermi level is related to the decrease of the bandgap for the increase of U. We elucidate the energy band diagram, which may serve to understand the electronic and magnetic properties of the ABX3-type transition metal tri-chalcogenides in general. [ABSTRACT FROM AUTHOR]

We have grown SrTiO3 thin films by rf-sputtering and studied its photoluminescence (PL) property after postannealing treatments. While the as-grown film does not show any PL signal, visible frequency PL emissions are induced by high temperature (T>550 °C) annealing. When subsequent low-T (50 °C) and long term (>8 months) annealing was made, the PL-spectra evolved into another pattern in which four distinct luminescence peaks appear simultaneously at λ=1.8, 2.2, 2.7, and 3.1 eV. We propose that these remarkable room temperature PL effects are due to both metastable and energetically stabilized defect states formed inside the band gap. [ABSTRACT FROM AUTHOR]