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In order to reduce the negative impact of the large-scale grid connection of residential photovoltaic (PV) equipment on the distribution network, it is of great significance to realize the real-time accurate identification of the grid connection state and its switching of residential PV equipment from the distribution network side. This paper introduces a non-intrusive method for identifying residential PV systems using transient features, leveraging the temporal convolutional network (TCN) model with attention mechanisms. Firstly, the discrimination and redundancy of transient features for residential PV devices are measured using a feature selection method based on the semi-Fisher score and maximal information coefficient (MIC). This enables the construction of a subset of identification features that best characterize the PV devices. Subsequently, a sliding window two-sided cumulative sum (CUSUM) event detection algorithm, incorporating a time threshold, is proposed for the real-time capturing of PV state switching and grid connection behavioral events. This algorithm effectively filters out disturbances caused by the on/off cycles of low-power residential devices and captures the transient time windows of PV behaviors accurately. On this basis, a TCN model with attention mechanisms is proposed to match the discerned event features by assigning varying weights to different types of characteristics, thereby facilitating the precise recognition of a PV grid connection and state-switching events. Finally, the proposed method is validated on a custom-designed non-intrusive experimental platform, demonstrating its precision and real-time efficiency in practical applications. [ABSTRACT FROM AUTHOR]

With the increasing integration of renewable energy into the power grid, there is a growing demand for converters that not only provide stable power, but also support auxiliary functions such as grid-voltage regulation. Consequently, grid-forming strategies have attracted significant attention. However, due to the complexities of analyzing nonlinear coupling systems, a comprehensive transient stability analysis of grid-forming converters is still being explored. Conventional analysis methods rely on a simplified quasi-steady-state model for grid-forming voltage source converters (VSCs) and focus on analyzing the transient instability phenomenon caused by the outer power loop. However, this oversimplified model may yield incorrect conclusions. To address this limitation, this paper develops a full-order model that includes quadratic nonlinear terms to accurately represent the system's nonlinear characteristics. The developed model is then decoupled into multiple low-order modes using a nonlinear decoupling method. These low-order modes can be analyzed using the mature inversing trajectory method, indirectly reflecting the transient stability of grid-forming VSCs under large disturbances. Through varying the inner and outer parameters, the transient stability of grid-forming VSCs is analyzed in detail. Furthermore, the analysis results are verified through hardware-in-loop (HIL) experiments. [ABSTRACT FROM AUTHOR]

Objective. To investigate the effectiveness of moxibustion combined with Chinese medicine in the treatment of spleen and stomach deficiency cold-type gastroparesis by meta-analysis and to provide the clinical basis for its treatment. Methods. A computer search of eight databases was performed for published and unpublished randomized controlled trials on moxibustion for spleen and stomach deficiency cold-type stomach pain from domestic and international clinical trial centers. The study was divided into a combination of a moxibustion and Chinese medicine group and a regular Western medicine group, and the outcome indicators were "effective" and "ineffective." The relative risk (RR) was used as the effect indicator for the dichotomous data, and the meta-analysis was performed using Reviewer Manager 5.4 and Stata17.0 software. Results. A total of 8 randomized controlled studies with 729 patients were included, and all studies were analyzed for comparability of patients' baseline information, with no statistically significant differences found (P > 0.05). The meta-analysis results showed that the pooled effect size RR for the eight studies was 1.24 (95% confidence interval 1.16–1.32), and the statistical significance test was Z = 6.69 (P < 0.05), indicating that the difference was statistically significant. Conclusion. The meta-analysis concluded that the efficacy of moxibustion combined with Chinese medicine for the treatment of spleen and stomach deficiency cold-type gastroparesis was superior to that of regular Western medicine, but more high-quality studies are needed to confirm this finding. [ABSTRACT FROM AUTHOR]

Shared development is an important means by which to improve people's livelihood and well-being in the new era. During the 13th Five-Year Plan period (2016-2020), China has made great achievements in the three major aspects of targeted poverty alleviation through industrial development, development of special rural areas, and equalization of urban and rural infrastructure and basic public services. In addition, the important experience of multi-agent participation, multi-mode guidance, and multi-line promotion has been accumulated in the individual, regional and urbanrural dimensions. However, there remain some deficiencies, such as low policy efficiency, poor matching ability, and prominent structural problems. At the beginning of the 14th Five-Year Plan (2021-2025), the task of enriching farmers through sharing has been faced with many challenges, such as major changes in the focus of poverty governance, greater numbers of restraints on the development of special rural areas, and heavy responsibilities of equalizing urban and rural infrastructure and basic public services. Therefore, it is necessary to acquire a profound understanding of the new development concept, and to continuously enrich farmers through sharing in terms of accelerating the improvement of the institutionalized poverty reduction system in the new era, actively building a green development system of agriculture and animal husbandry in special rural areas, and striving to create a fair and complementary urban and rural infrastructure and basic public service system. [ABSTRACT FROM AUTHOR]

A superhydrophobic ORMOSIL (organically modified silicate) coating was in situ fabricated on a wood surface by ammonia–hexamethylisilazane (HMDS) vapor treatment. The wood was immerged in tetraethoxysilane (TEOS), and then the TEOS absorbed on the wood surface was hydrolyzed and condensed to hydrophobic SiO2 nanoparticles with ammonia and HDMS vapor treatment. The effect of the treatment temperature and time on the hydrophobicity of wood was investigated. At a treatment temperature of 50 °C, a superhydrophobic surface was achieved on the wood with a treatment time longer than 2 h. SEM images indicated that there were SiO2 nanoparticles fabricated on the wood surface, and FTIR revealed that the hydrophobic –Si(CH3)3 groups were incorporated on the wood surface. The ORMOSIL-modified wood possessed improved liquid repellency. The water absorption decreased significantly from 72.3% to 31.9% after modification. [ABSTRACT FROM AUTHOR]