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New equipment and technical applications on distribution networks demonstrate a tendency of physical data integration， and distribution network morphology is also changing rapidly. Therefore， adaptability testing and verification on new equipment and technology are required to improve distribution network reliability and resource scheduling capability. To this end， the construction and application of real tests for intelligent distribution networks are studied. Firstly， the purpose of the platform and system composition are analyzed. Secondly， the specific implementation methods of power， neutral point test platform， medium-voltage AC/DC architecture test platform， distribution cables， channel test platform， and other platforms are introduced. Finally， three major test scenarios are designed： earthing test 10 kV primary and secondary fusion circuit breaker， functional assessment test on intelligent fully automatic FA， and fault sensing test on low-voltage transformer area. The true test platform for intelligent distribution networks is applied to make up for the deficiency of the traditional testing methods for distribution networks and equipment.

This paper centers on the core business application—the automatic topology identification in transformer areas—of distribution IoT with new energy as its mainstay. It proposes an automatic topology identification technology testing scheme that considers identification reliability， high identification accuracy， and anti-disturbance capability. Besides， a unique “edge-to-end” interaction test platform for the distribution IoT area is developed. Afterward， the functions and performance of the mainstream technical schemes of Zhejiang Electric Power Co.， Ltd. are evaluated in all aspects. The “active current injection plus frequency-domain signal detection” is selected as the optimal technical scheme for topology identification. The topology identification technology testing and research can lay the application foundation for the subsequent interconnection， intercommunication， and interoperability of the distribution IoT and the transformation of the distribution networks.

It has been a popular topic recently that eco-friendly materials， in place of any other kinds， are used as insulation media for power equipment. So far， the relevant research mostly focuses on the performance optimization of eco-friendly insulating materials. However， little attention is paid to whether or not it can be applied to power distribution equipment. Therefore， performance differences between key equipment in transformation areas for which eco-friendly and traditional insulation media are used respectively. Then， eco-friendly insulation media are used to manufacture distribution transformers， switching cabinets， and power cables， and the electrical performance of the media is evaluated. Finally， a distribution transformer area based on eco-friendly power equipment is constructed. The results show that the eco-friendly power equipment prepared by using vegetable insulating oil， gas mixture C4F7N/CO2 （perfluoroisobutyronitrile/carbon dioxide）， and cable insulation material polypropylene is similar in performance to traditional equipment； it can meet the application demands of power equipment on distribution networks. The results also verify the practicability of power equipment made from eco-friendly insulating media and the compatibility between various equipment， which can provide a reference for implementing and promoting eco-friendly distribution networks in China.

ObjectiveTo explore the effects of anxiety and depression on Internet gaming disorder in medical students， and to evaluate the moderating effect of gender， so as to provide references for the prevention and intervention of Internet gaming disorder in medical students.MethodsIn November 2021， a total of 11 771 medical students from a medical college in Sichuan province participated in an online survey through Wenjuanxing platform. Participants completed the Self-rating Anxiety Scale （SAS）， Self-rating Depression Scale （SDS） and the nine-item Internet Gaming Disorder Scale-Short Form （IGDS9-SF）. Then a hierarchical multiple regression analysis was conducted to discuss the moderating role of gender in the relationships between anxiety， depression and Internet gaming disorder in medical students.Results①Males scored lower on SDS （t=-8.302， P

By aggregating the scattered dispatchable resources in power grids through dispatchable resource aggregation technology， coordination and control technology， and power market trading technology， virtual power plants （VPPs） have brought about mutually interactive operation in a friendly manner. Firstly， the paper summarizes the responsiveness assessment technology for dispatchable resource and the differentiated resource aggregation methods for participation in power markets in terms of VPP- aggregated modeling technology. Secondly， it analyzes different modes of VPP resource organization and market participation aimed at demand-side response and power spot market. Lastly， the paper analyzes key issues of VPPs for new power systems and has a full view of risk management， external environment， market promotion， as well as security potentially incurred by multiparty participation.

Objective: To provide the theory basis for clinical diagnosis, treatment and prognosis of sudden deafness patients, we detected the relative factors of degree of tinnitus of the patients with sudden deafness., Method: Prospective analysis was used to compare degree of tinnitus with sex, ears, age, degree of hearing lose, hearing curve type and curative effect of tinnitus and sudden deafness., Result: Tinnitus was detected in 87.2% in the 70 patients who with sudden deafness, and the most and least degree of tinnitus patients was the degree 3 (32.9%) and the degree 5 and 6 (0). The total effective rate of sudden deafness and tinnitus was 66.2% and 74.3%, respectively. The statistical analysis shown the degree of tinnitus was not related to sex, ears, age, degree of hearing lose, auditory curve type and curative effect of tinnitus and sudden deafness (P > 0.05)., Conclusion: There was a high rate of tinnitus occurrence in sudden deafness patients, and the moderate degree predominated. The curative effect of tinnitus was better than sudden deafness. There was no relationship between the degree of tinnitus and sex, ears, age, degree of hearing lose, auditory curve type and curative effect of tinnitus and sudden deafness.

In this study, a fast, selective and sensitive ultra-performance liquid chromatographic method (UPLC) with photodiode array detection (DAD) was developed to determine 12 active compounds, such as flavonoids, ferulic acid, caffeic acid phenethyl ester, etc. in propolis. The propolis sample was diluted with methanol and extracted by sonication. The gradient separation was achieved within 9.5 min by using an Acquity BEH C18 column (100 mm x 2.1 mm, 1.7 microm) with 0.4% phosphoric acid aqueous solution and methanol as the mobile phase. The experimental parameters were optimized and adapted to analyse propolis samples from different production areas in China. The spiked recoveries were 90.1% - 104.3% with relative standard deviations of 2.12% -4.90%. This method can be used as a novel method for quality control of propolis. The results are validated through testing 106 propolis samples from various production areas.