A VMD and LSTM based hybrid model of load forecasting for power grid security

As the basis for the static security of the power grid, power load forecasting directly affects the safety of grid operation, the rationality of grid planning, and the economy of supply-demand balance. However, various factors lead to drastic changes in short-term power consumption, making the data more complex and thus more difficult to forecast. In response to this problem, a new hybrid model based on Vari-ational mode decomposition (VMD) and Long Short-Term Memory (LSTM) with seasonal factors elimination and error correction is proposed in this paper. Comprehensive case studies on four real-world load datasets from Singapore and the United States are employed to demonstrate the effectiveness and practicality of the proposed hybrid model. The experimental results show that the prediction accuracy of the proposed model is significantly higher than that of the contrast models. Index Terms-Power grid security, short-term load forecasting , seasonal factors elimination, error correction

The Effects of Precursors on the Morphology and Chemical Mechanical Polishing Performance of Ceria-Based Abrasives

Ceria-based abrasives are widely used in precision chemical mechanical polishing (CMP) fields, such as thin film transistor liquid crystal display (TFT-LCD) glass substrates and integrated circuits, because of their excellent physicochemical properties. Rare earth carbonates, as precursors of ceria-based abrasives, directly affect the morphology of ceria-based abrasives, which, in turn, affects the material removal rate (MRR) and the surface roughness (Ra) after polishing. Herein, rare earth carbonates with different morphologies were obtained by adjusting reaction parameters during precipitation, including flake, spindle, and spheroid. Moreover, the phase of precursors was analyzed, and the evolution process of morphology from precursors to ceria-based abrasives was investigated. Furthermore, the effect of precursors on the polishing performance of ceria-based abrasives was explored. The results show that the primary particles of ceria-based abrasives are near-spherical, but the morphology and dispersion of the secondary particles are obviously inherited from precursors. Among them, near-spherical ceria-based abrasives prepared by nearly monodisperse near-spherical precursors show better uniformity and higher dispersion, and they not only achieve the lowest Ra but also obtain a higher MRR of 555 nm/min (9 wt.%) for polishing TFT-LCD glass substrates. The result is significant for the further optimization and application of high-performance ceria-based abrasives

Multi-energy System Planning and Configuration Study for Low-Carbon Parks Based on Comprehensive Optimization Objectives

The reasonable planning and configuration of composite system in low-carbon park is of great significance for improving system energy efficiency and reducing costs and pollutant emissions. Firstly, based on the energy-demand fast prediction method for park and the composite energy system dynamic simulation platform, this paper proposed an optimal planning and configuration method for low-carbon park composite energy system, and established a hybrid optimization algorithm combining Hook-Jeff algorithm and particle swarm optimization. Secondly, by taking a multi-energy system with triple supply of cooling, heating and power system coupled with ground source heat pump, energy storage, and gas boiler in a typical low-carbon park as an example, a comparative analysis was made on the configuration results and optimization speed with different optimization algorithms, and a study was conducted on the impacts of different optimization objectives such as optimal comprehensive optimization objective and lowest whole life-cycle cost and energy consumption on the capacity optimization configuration results and typical daily operation situation. The results show that the proposed optimal configuration method and hybrid optimization algorithm can ensure the optimization capacity and accuracy with higher calculation performance. The energy system configuration results with optimal comprehensive evaluation objectives can take into account multiple factors such as system cost, economic operation, environmental impacts and low-carbon emissions, which can effectively realize the optimal energy form of low-carbon parks

Study on Key Technical Route and Construction Mode of Low-Carbon Park

The potential for energy conservation and emission reduction in parks is enormous, promoting the popularization of low-carbon parks is a necessary means to promote the green and low-carbon transformation of energy consumption and achieve China’s ‘dual carbon’ goals. This article summarizes and extracts four main technical routes for building low-carbon parks through research on low-carbon parks and building cases at home and abroad: energy conservation and low-carbon construction of architectural noumenon, proactive energy conservation and operational carbon reduction, internal development of renewable energy, and external green energy input. Horizontal comparison and qualitative analysis of the four technical routes adopted in each typical case, summarizing and proposing eight models and typical application scenarios for building low-carbon parks, providing a theoretical basis and implementation suggestions for low-carbon development of the park

Identification of a <i>SCN4A</i> mutation in a large Chinese family with atypical normokalemic periodic paralysis using whole-exome sequencing

Objectives Normokalemic periodic paralysis (NormoKPP) of skeletal muscle is an autosomal dominant disorder caused by mutations in the gene encoding voltage-gated sodium channel protein type 4 subunit alpha ( SCN4A), which leads to ion channel dysfunction. Little is known about the relationship between genotype and the clinical symptoms of NormoKPP. The present study aimed to evaluate the genetic variation in a large Chinese family with NormoKPP. The patients in this pedigree did not respond to saline treatment, but calcium gluconate treatment was effective. Methods We performed a series of clinical examinations and genetic analyses, using whole-exome and Sanger sequencing, to examine the mutation status of SCN4A in a Chinese family segregating for NormoKPP. Results Whole-exome sequencing revealed a c.2111C&gt;T substitution in SCN4A in most of the affected family members. This mutation results in the amino acid substitution p.T704M. Conclusions These results support a causative role of this mutation in SCN4A in NormoKPP, and provide information about the relationship between genotype and atypical clinical symptoms. </jats:sec