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Traditional studies on the carrying capacity of groundwater resources mainly focus on a comprehensive evaluation, and this paper provides quantitative prediction and early warning on the carrying capacity of groundwater resources, which is important for groundwater management and protection. This study constructed an early warning indicator system for the carrying capacity of groundwater resources, established an early warning method on the carrying capacity of groundwater resources, determined the early warning grades of Henan Province and various cities from 2023 to 2025, and analyzed the spatial distribution pattern. The results showed that the early warning grades of Henan Province from 2023 to 2025 were mild warnings. In the subsystems, the early warning grades of the groundwater resources and economic society systems were mild warnings, while the early warning grades of the ecological environment system were moderate warnings. The early warning grades of the carrying capacity of groundwater resources in all cities were basically mild or moderate warnings, showing a downward trend. This study establishes an early warning method on the carrying capacity of groundwater resources that includes the selection of early warning indicators, prediction of indicators, and determination of the early warning grades which can be a reference for other regions. HIGHLIGHTS Consider groundwater, economic society, and ecological environment as a GEE system.; An evaluation indicator system covering the GEE system is constructed.; An early warning method on the carrying capacity of groundwater resources is established.; The method is applied in Henan to quantitatively predict and early warn.;

The traditional groundwater overexploitation restoration only considers the impact on groundwater, on the basis of which, this paper also comprehensively considers the impact on economic society and the ecological environment. Based on analyzing the effect of groundwater overexploitation restoration on the groundwater–economic society–ecological environment (GESEE) system, an evaluation indicator system covering the GESEE system was constructed, an evaluation method for the effect of groundwater overexploitation restoration was established, and the effects were evaluated for Hebei Province, China, from 2014 to 2019. The results showed that the effect of groundwater overexploitation restoration in Hebei Province was obvious, and the grade of the groundwater overexploitation restoration effect improved from fair to good. The grade of the groundwater overexploitation restoration effect in most cities was improved to good. The measures that most affected the effect of groundwater overexploitation restoration in Hebei Province are strict control of extraction and reduction of consumption, while measures such as the replacement of water sources also play a significant role. An evaluation indicator system constructed in this paper can help to promote sophisticated effect evaluation of groundwater overexploitation restoration and improve the understanding and management of groundwater overexploitation restoration. HIGHLIGHTS An evaluation indicator system covering the groundwater–economic society–ecological environment system is constructed.; An evaluation method for the effect of groundwater overexploitation restoration is established.; The evaluation method is applied at both provincial and municipal levels in Hebei Province, one of the most severe groundwater overexploitation areas in the world.;

Wireless power transmission technology based on coil coupling has been widely applied in various fields. However, the performance of the system is affected by the malposition of the transmission coil-couple, which is inevitable in the wireless power transmission system (WPTS). In this study, a multi-transmitter coil array is proposed to build a more uniform magnetic flux density for the WPTS, intending to enhance the performance of the WPTS in the case of coil-couple malposition. The model of the transmission system is built and different coil arrangement methods are analyzed. Then, the magnetic field distributions of the proposed WPTS with different coil arrays are compared using numerical simulations. Experiments are conducted to investigate the performances of the designed WPTS. The results show that WPTS with a seven-coil array can provide a more uniform magnetic field for the WPTS, whose relative deviation of output power is less than 28.55%. This study provides some clues for improving the performance of the WPTS through different arrangements of the transmitter coils.

Establishing an ultra-high-precision link for time–frequency comparisons between satellites and ground stations is critically important. This endeavor is fundamental to the advancement of pioneering space science exploration and the development of a robust space-based time–frequency system featuring ultra-high-precision space atomic clocks. In response to the requirements for assessing the long-term stability of high-precision space atomic clocks, we have designed and implemented a satellite–ground microwave time–frequency comparison system and method based on a three-frequency mode. Ground-based experimental results demonstrate that the equipment layer can achieve a satellite–ground time comparison accuracy better than 0.4 ps (RMS), with the equipment delay stability (ADEV) for all three frequencies being better than 8 × 10−18 at 86,400. By leveraging the ground-based experimental results, we constructed a satellite–ground time–frequency comparison simulation and verification platform. This platform realizes ultra-high-precision satellite–ground time–frequency comparison based on the China Space Station (CSS). After correcting various transmission delay errors, the satellite–ground time comparison achieved an accuracy better than 0.8 ps and an ADEV better than 2 × 10−17 at 86,400. This validation of our novel satellite–ground time–frequency comparison system and method, capable of achieving an 10−17 magnitude stability, is not only a significant contribution to the field of space time–frequency systems but also paves the way for future advancements and applications in space science exploration.

ADHD is a common disease in children, and the pathogenesis is still unclear. Attention deficit is the main manifestation of ADHD, which has a serious impact on children’s learning and growth. The treatment of ADHD is mainly western medicine, supplemented by psychotherapy. More and more studies have shown that ADHD has similar characteristics to psychological diseases, and dopamine beta hydroxylase gene abnormality is the common feature of most mental diseases. In view of the potential relationship between ADHD and dopamine β hydroxylase gene, this paper will study the polymorphism of dopamine β hydroxylase gene in children with ADHD under the nursing intervention mode. This paper is divided into three parts. The first part is theoretical research. In this part, we deeply analyze ADHD. We think that the pathogenesis of ADHD mainly comes from four factors: heredity, environment, nutrition, and behavior. In order to further test the relationship between ADHD and dopamine beta hydroxylase gene, the corresponding experimental model was established in the second part of this paper. All the samples in the experiment are from real cases. The experimental principle and specific operation steps are given in detail. In order to facilitate comparison, the same number of control groups was established in addition to the real disease. The third part is the experimental results and analysis. After a number of comparative experiments, through the analysis of experimental data, we believe that ADHD is closely related to the gene of dopamine beta hydroxylase. Among them, the A2 gene in the patient group was significantly more than that in the normal group, which further verified that ADHD has the characteristics of common psychological diseases.

This article conducted an investigation on the data associated with the academic English writing course offered through Massive Open Online Courses (MOOCs). This article was to gain initial insights into the development of the course. Employing a case study methodology. This article conducted a sample survey to evaluate students' perceptions of the course. Building upon these findings. This article undertook a comprehensive literature review and integrated the proposed teaching ideas of several experts to develop a MOOC teaching model for academic English writing. This article optimizes teaching strategies and enhances education and training programs across three key dimensions: universities, teachers and students, and the platform. By doing so, the overall quality of academic English writing instruction could be significantly improved. [ABSTRACT FROM AUTHOR]