The school commuting path is an important space for elementary school students to engage with society and nature.The design of these paths reflects concerns for children's rights and healthy development and has cr...The school commuting path is an important space for elementary school students to engage with society and nature.The design of these paths reflects concerns for children's rights and healthy development and has crucial impacts on creating supportive environments for children.The scientific evaluation of the child-friendly level of school commuting paths forms a significant basis for shaping child-friendly environments and promoting the comprehensive development of children.Additionally,due to the unique climatic conditions,cold climate cities excert a distinct impact on children's behavior,activities,and physical and mental health compared to cities in other climate zones.This study,from the perspective of child-friendliness,constructs an evaluation system for school commuting paths in cold climate cities,based on children's behavioral characteristics and environmental needs.The system includes dimensions such as safety,diversity,and comfort.With children and their caregivers as the evaluators,the study applies structural equation modeling to assign weights to the various dimension indicators in the evaluation system.The research focuses on five elementary schools in the Nangang District of Harbin City,using methods such as machine learning,space syntax,and field surveys to assess the school commuting paths.Building upon these findings,the study constructs the characteristic profile of the commuting paths and proposes evidence-based control and optimization strategies for different types of school commuting paths in cold climate cities from a child-friendly perspective.展开更多
In high-power three-level converters, busbar stray inductance critically influences switching transient and thermal distribution. This paper establishes a parametric stray inductance model for laminated busbars and an...In high-power three-level converters, busbar stray inductance critically influences switching transient and thermal distribution. This paper establishes a parametric stray inductance model for laminated busbars and analyses its impact on commutation paths. To resolve thermal imbalance, a power loss thermal balance method optimizes control strategies, enabling stable commutation path switching and preventing system instability at switching points. The key is to propose weighting factors based on stray parameters for dynamic energy exchange among internal, external and clamp switches, combined with case temperature-dependent modulation to achieve thermal balance in three-level converters. The accuracy of the model established and the feasibility of the adopted approach are verified by simulation studies in MATLAB/Simulink and experiments based on a 900 V alternating current power system.展开更多
基金funded by National Natural Science Foundation of China Youth Project(No.52308018)China Higher Education Institution Industry-University-Research Innovation Fund(2024SE031)+1 种基金Doctoral Postdoctoral Funding Project in Heilongjiang Province(No.LBH-Z22159)Fundamental Research Funds for Central Universities(HIT.HSS.202312)。
文摘The school commuting path is an important space for elementary school students to engage with society and nature.The design of these paths reflects concerns for children's rights and healthy development and has crucial impacts on creating supportive environments for children.The scientific evaluation of the child-friendly level of school commuting paths forms a significant basis for shaping child-friendly environments and promoting the comprehensive development of children.Additionally,due to the unique climatic conditions,cold climate cities excert a distinct impact on children's behavior,activities,and physical and mental health compared to cities in other climate zones.This study,from the perspective of child-friendliness,constructs an evaluation system for school commuting paths in cold climate cities,based on children's behavioral characteristics and environmental needs.The system includes dimensions such as safety,diversity,and comfort.With children and their caregivers as the evaluators,the study applies structural equation modeling to assign weights to the various dimension indicators in the evaluation system.The research focuses on five elementary schools in the Nangang District of Harbin City,using methods such as machine learning,space syntax,and field surveys to assess the school commuting paths.Building upon these findings,the study constructs the characteristic profile of the commuting paths and proposes evidence-based control and optimization strategies for different types of school commuting paths in cold climate cities from a child-friendly perspective.
基金sponsored by the National Natural Science Foundation of China (Grant No. 52272339)。
文摘In high-power three-level converters, busbar stray inductance critically influences switching transient and thermal distribution. This paper establishes a parametric stray inductance model for laminated busbars and analyses its impact on commutation paths. To resolve thermal imbalance, a power loss thermal balance method optimizes control strategies, enabling stable commutation path switching and preventing system instability at switching points. The key is to propose weighting factors based on stray parameters for dynamic energy exchange among internal, external and clamp switches, combined with case temperature-dependent modulation to achieve thermal balance in three-level converters. The accuracy of the model established and the feasibility of the adopted approach are verified by simulation studies in MATLAB/Simulink and experiments based on a 900 V alternating current power system.
