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An early warning method based on Session Initiation Protocol (SIP) concept for generator set electrical control abnormal response is proposed. The first is to clean the electrical data of the generator set by SIP. Using Supervisory Control and Data Acquisition (SCADA) and Generalized Linear Models (GLM) algorithm, a linear model is constructed to analyze the electrical control of generating units. Using the Autoregressive Integrated Moving Average Model (ARIMA), an abnormal response early warning model for electrical control of generating units is established. BP neural network is used to train the abnormal response data of the generator set electrical control. According to the current response data, the model prediction is realized, and the early warning of the abnormal response of the generator set electrical control is effectively realized. The simulation results show that the proposed method can effectively reduce the early‐warning error, false alarm rate, and early‐warning delay of generator electrical control abnormal response. [ABSTRACT FROM AUTHOR]

The valley index is a promising degree of freedom for information processing in electronic devices. However, the researches on valley polarization are mainly focused on ferromagnetic order, which breaks the time reversal symmetry simultaneously. Here, a novel paradigm for achieving stacking order modulated anomalous valley Hall (AVH) effect is proposed in antiferromagnetic monolayers. The paradigm involves the introduction and reversal of nonuniform potentials by modulating the position of substrate, to break the combined symmetry of spatial inversion and time reversal (PT symmetry) and achieve stacking-dependent valley spin splitting. Based on first-principles calculations, we discover spontaneous valley polarization in antiferromagnetic Cr2CH2 MXene and stacking-dependent valley spin splitting in Cr2CH2/Sc2CO2 heterostructure. Furthermore, switching the ferroelectric polarization of monolayer Sc2CO2 results in a semiconductor-metal transition in Cr2CH2/Sc2CO2, accompanied by the disappearance of valley physics. Our findings provide an alternative way to develop controllable valleytronics devices based on antiferromagnetic monolayers.

The two‐dimensional (2D) materials InX (X = O, Se), experimentally available thus far, can become a ferromagnetic half metal under hole doping, though the charge neutral states of them are nonmagnetic semiconductors. Based on such an electronic characteristic, a theoretical model of magnetic tunnel junction (MTJ) is proposed composed only of one of the 2D InX. In doing so, the two semi‐infinite pieces of 2D InX in the half‐metallic state is assumed as the opposite electrodes which are separated by a strip of the same material but in its nonmagnetic state. Owing to the 2D nature of InX, the half metal electrodes of the InX device induced by hole doping can be achieved by using split gating technique. The numerical simulations identify a proper hole doping concentration, at which 100% tunneling magnetoresistance (TMR) ratios can be realized, accompanying an appreciable conductance of majority spin electron under parallel magnetization configuration. Under a finite bias voltage, the TMR ratio remains high. Therefore, the proposed device model is an ideal candidate for future spintronics applications. It enables electrical control of TMR and circumvents the detriment of hetero‐interface disorder inevitable in conventional MTJs. [ABSTRACT FROM AUTHOR]

Hybrid excitons, characterized by their strong oscillation strength and long lifetimes, hold great potential as information carriers in semiconductors. They offer promising applications in exciton-based devices and circuits. MoSe 2 /WS 2 heterostructures represent an ideal platform for studying hybrid excitons, but how to regulate the exciton lifetime has not yet been explored. In this study, layer hybridization is modulated by applying electric fields parallel or antiparallel to the dipole moment, enabling us to regulate the exciton lifetime from 1.36 to 4.60 ns. Furthermore, the time-resolved photoluminescence decay traces are measured at different excitation power. A hybrid exciton annihilation rate of 8.9 × 10 -4  cm 2  s -1 is obtained by fitting. This work reveals the effects of electric fields and excitation power on the lifetime of hybrid excitons in MoSe 2 /WS 2 1.5° moiré heterostructures, which play important roles in high photoluminescence quantum yield optoelectronic devices based on transition-metal dichalcogenides heterostructures., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)