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In recent years, with the development of societies and economies, the demand for social electricity has further increased. The efficiency and accuracy of electric-load forecasting is an important guarantee for the safety and reliability of power system operation. With the sparrow search algorithm (SSA), long short-term memory (LSTM), and random forest (RF), this research proposes an SSA-LSTM-RF daily peak-valley forecasting model. First, this research uses the Pearson correlation coefficient and the random forest model to select features. Second, the forecasting model takes the target value, climate characteristics, time series characteristics, and historical trend characteristics as input to the LSTM network to obtain the daily-load peak and valley values. Third, the super parameters of the LSTM network are optimized by the SSA algorithm and the global optimal solution is obtained. Finally, the forecasted peak and valley values are input into the random forest as features to obtain the output of the peak-valley time. The forest value of the SSA-LSTM-RF model is good, and the fitting ability is also good. Through experimental comparison, it can be seen that the electric-load forecasting algorithm based on the SSA-LSTM-RF model has higher forecasting accuracy and provides ideal performance for electric-load forecasting with different time steps. [ABSTRACT FROM AUTHOR]

Bi 2 O 3 and Al 2 O 3 were proven to separately have an impact on grain growth of LiZn ferrite ceramics. In this study, we synthesized LiZnTiMn ferrite ceramics under low temperature (<920 °C) using rationally designed formula of Bi 2 O 3 -Al 2 O 3 as sintering agents. Microstructures, densities, and ferromagnetic performances were systematically investigated. Results show that appropriate amount of Bi 2 O 3 -Al 2 O 3 leads to successful sintering of LiZnTiMn ferrites even below 900 °C. X-Ray diffraction (XRD) and scanning electron microscopy (SEM) results show that spinel structure ferrite ceramics were obtained and that the addition of Bi 2 O 3 -Al 2 O 3 accelerated solid-state reaction. Corresponding ferromagnetic properties, including saturation induction (B s), remanence square ratio, coercivity (H c), ferromagnetic resonance linewidth (ΔH), and M s , were also investigated. At 920 °C, with addition amount of x =1 wt %, we obtain excellent performance: B s =306 mT, B r /B s =0.849, H c =2.34Oe, and ΔH =275 Oe. Results indicate that Bi 2 O 3 -Al 2 O 3 is promising sintering agent for low-temperature sintering of LiZnTiMn ferrite ceramics. • LiZn ferrites prepared by low-temperature sintering (below 950 °C) and typical spinel structure of samples were obtained. • It has proved that Bi 2 O 3 -Al 2 O 3 is a satisfactory sintering agent for low-temperature in this study. • B s increased from 141 to 321 mT with the ΔH decreased from 749 to 275 Oe. [ABSTRACT FROM AUTHOR]

The apetala/ethylene responsive factor (AP2/ERF) family is one of the largest plant-specific transcription factors and plays a vital role in plant development and response to stress. The apetala 2.4 (RAP2.4) gene is a member of the AP2/ERF family. In this study, ClRAP2.4 cDNA fragment with 768 bp open reading frame was cloned and the resistance of ClRAP2.4 overexpression to low temperature was investigated to understand whether RAP2.4 is involved in low-temperature stress in chrysanthemum (Chrysamthemum lavandulifolium). Phylogenetic analysis showed that ClRAP2.4 belonged to the DREB subfamily and was most closely related to AT1G22190. ClRAP2.4 was localised in cell nucleus and promotes transcriptional activation in yeast. In addition, ClRAP2.4 was transformed by using the Agrobacterium -mediated leaf disc method, and four overexpression lines (OX-1, OX-2, OX-7, and OX-8) were obtained. The activities of superoxide dismutase and peroxidase, and proline content in leaves in the four overexpression line were higher than those in the wild type (WT), whereas the electrical conductivity and malondialdehyde content were decreased, indicating that the tolerance of plants with ClRAP2.4 overexpression to cold stress was increased. RNA-Seq showed 390 differentially expressed genes (DEGs) between the transgenic and WT plants(229 upregulated, 161 downregulated). The number of ABRE , LTR , and DRE cis -elements in the promoters of DEGs were 175, 106, and 46, respectively. The relative expression levels of ClCOR , ClFe/MnSOD , ClPOD , ClNCL , ClPLK , ClFAD , and ClPRP in the transgenic plants were higher than those in WT plants at low temperatures. These data suggest that ClRAP2.4 may increase chrysanthemum tolerance to cold stress. The apetala/ethylene responsive factor (AP2/ERF) family plays important in plant development and response to stress. This article mainly tells about how RAP2.4 is involved in low-temperature stress of chrysanthemum (Chrysamthemum lavandulifolium). We found that the overexpression of ClRAP2.4 in chrysanthemum increased tolerance to cold stress. The relative expression levels of ClCOR and other genes were higher in transgenic plants at low temperature. This experiment provides a theoretical basis for the research on the tolerance of chrysanthemum to cold stress. [ABSTRACT FROM AUTHOR]