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This article proposes an improved model-free deadbeat predictive current control (MFCC) method for permanent magnet synchronous motors (PMSMs) based on the ultralocal model and H∞ norm. Firstly, the traditional deadbeat predictive current control (DPCC) method is introduced and a theoretical analysis is conducted on its sensitivity to parameters. Building upon this, the limitations of model dependence and the limited robustness of the deadbeat predictive current control method based on the extended state observer (ESO-DPCC) are theoretically analyzed. Furthermore, an improved MFCC method based on the ultralocal model is proposed, and the influence of the observer on MFCC is theoretically analyzed. This study combined the proposed method with the H∞ norm, and the optimal coefficients of the observer were tuned to enhance the robustness and dynamic performance of the current loop. Finally, the proposed algorithms were validated on a 400 W PMSM platform. [ABSTRACT FROM AUTHOR]

To meet the environmental protection and flame retardancy requirements for epoxy resins (EPs) in certain fields, in this study, a novel triazine-ring-containing DOPO-derived compound (VDPD), derived from vanillin, 2,4-Diamino-6-phenyl-1,3,5-triazine, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), was synthesized using a one-pot method. Flame-retardant epoxy resin (FREP) was prepared by adding various ratios of VDPD to EP and curing with 4,4-diaminodiphenylmethane (DDM). The curing behavior, thermal stability, mechanical properties, and flame-retardant properties of the FREP were examined in various tests. According to the results, when the amount of VDPD added to the EP increased, the glass transition temperature of the FREP decreased linearly, and the flame-retardant properties gradually improved. With a 0.4 wt.% P content, the vertical burning rating of EP/DDM/VDPD-0.4 (according to the theoretical content of VDPD) reached the V-0 level, and the LOI value reached 33.1%. In addition, the results of a CCT showed that the peak heat release rate (PHRR) of EP/DDM/VDPD-0.4 decreased by 32% in comparison with that of the EP. Furthermore, compared with those of the EP, the tensile strength of EP/DDM/VDPD-0.4 decreased from 80.2 MPa to 74.3 MPa, only decreasing by 6 MPa, and the tensile modulus increased. Overall, VDPD can maintain the mechanical properties of EP and effectively improve its flame-retardant properties. [ABSTRACT FROM AUTHOR]

Background: The purpose of this research is to summarize the academic expertise of Professor Lu Zhizheng in the treatment of Chronic Atrophic Gastritis, and to explain his clinical reasoning and common prescriptions in the treatment of CAG., Methods: Professor Lu's outpatient cases of CAG from January 2008 to December 2021 were selected, and the PageRank algorithm was applied on the FangNet platform to analyze the usage frequencies of herbs, their four natures and five flavors according to Traditional Chinese Medicine, core herbs, and herb clustering patterns, with the goal of summarizing the distinguishing features of Professor Lu's academic and clinical approach to CAG. A total of 170 patients from 252 consultations were included in this study. The prescriptions involved a total of 239 herbs, which occurred a cumulative 4339 times. The herb natures were mainly warm, neutral, and slightly cold, and the herb flavors were predominantly sweet, bitter, and pungent. The channel tropism of the selected herbs primarily targeted the spleen, stomach, and lung meridians. Herb rank analysis showed that 34 herbs, including Gancao, Taizishen, Banxia, Huanglian, Shengjiang, Baizhu, Yiyiren, Maiya, Cangzhu, and Kuxingren, were the driver herbs used by Professor Lu for the treatment of CAG., Results: Herb-herb co-occurrence/exclusivity analysis revealed 10 sets of frequently used herb pairs; herb cluster analysis yielded 10 herb clusters. These results reflected the emphasis Professor Lu placed on protecting Qi and Yin while clearing damp-heat. Professor Lu Zhizheng utilized dialectics reinforced with flexible thinking in the treatment of CAG, and emphasized that identifying the pathogenesis and addressing the syndrome should be prioritized., Conclusions: The characteristic treatment strategy aimed to replenish Qi and nourish Yin, clear away damp-heat, and treat CAG patients comprehensively under the guidance of established principles.

What Is Already Known on This Topic?: There is a lack of comprehensive data on the coverage of the human papillomavirus (HPV) vaccine in China. The limited published literature hampers our ability to accurately assess the current situation., What Is Added by This Report?: This study aimed to determine the rates of HPV vaccine coverage based on data from the electronic vaccination registry reported to the China Immunization Information System between 2017 and 2022. While there was an increase in HPV vaccine coverage each year, the overall coverage remained below the optimal level., What Are the Implications for Public Health Practice?: This study presents evidence of low HPV vaccine coverage when administered outside of a national immunization program. Therefore, it is recommended that the HPV vaccine be included in the National Immunization Program in order to meet the 2030 WHO target of achieving 90% vaccination coverage for girls by the age of 15., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)