Urban green spaces play a crucial role in enhancing the well-being of urban residents and promoting sustainable urban development. However, optimizing the planning and management of urban green spaces to meet resident...Urban green spaces play a crucial role in enhancing the well-being of urban residents and promoting sustainable urban development. However, optimizing the planning and management of urban green spaces to meet residents' diverse needs and preferences poses a considerable challenge. This study addresses this challenge by employing a landsenses ecology approach, integrating residents' perspectives into the planning and design of urban green spaces. Starting from human needs, a conceptual framework for the meliorization model of urban green spaces is constructed, grounded in the principles of landsense creation and incorporating a “design-simulation-management” process. Through this model, the mechanisms driving the meliorization process are explored. This study contributes to improving the meliorization process in landsenses ecology, while expanding the theoretical framework and methodology of landscape ecology. By emphasizing the dynamic interactions between land planning, construction, and residents' experiences, this study provides valuable insights into the dynamic development of urban green spaces, facilitating the implementation of sustainable urban development strategies and practices.展开更多
Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands ...Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands hours even years. In order to achieve a rapid evaluation technique and to seek lifetime extension methods, a lifetime calculation formation was drawn out in consideration of the vehicle driving cycle and the working condition factors. Bench experiments were individually carried out on two fuel-cell stacks same as ones applied on vehicle, and the performance decay rates of the two stacks were obtained under four operation conditions of changing load cycle, start-stop cycle, idling and heavy load. As a result, the predicted lifetimes rather conform to the actual running status in road test. And the research on the fuel cell performance decay rates under different load conditions was also done. Consequently, an unexpected finding was discovered that operating under micro-current has an effect on recovering fuel cell performance. The vehicle fuel cell rapid assessment method only requires four laboratory tests of driving cycle, load cycle, idle operating conditions and heavy load conditions, and the whole process merely lasts less than 250 h. These experimental results can be used to predict the vehicular fuel cell lifetimes on various utility models or driving cycles, therefore to optimize the application model to prolong the fuel cell lifetime. Actually in the experiment, it has already been proved successfully that the fuel cell lifetime could be extended from 1 100 h to 2 600 h by optimizing operating mode. The quick evaluation method is helpful to develop extended life fuel cell and to deplete fuel cell for a longer time.展开更多
基金National Natural Science Foundation of China,No.32371650,No.31872688。
文摘Urban green spaces play a crucial role in enhancing the well-being of urban residents and promoting sustainable urban development. However, optimizing the planning and management of urban green spaces to meet residents' diverse needs and preferences poses a considerable challenge. This study addresses this challenge by employing a landsenses ecology approach, integrating residents' perspectives into the planning and design of urban green spaces. Starting from human needs, a conceptual framework for the meliorization model of urban green spaces is constructed, grounded in the principles of landsense creation and incorporating a “design-simulation-management” process. Through this model, the mechanisms driving the meliorization process are explored. This study contributes to improving the meliorization process in landsenses ecology, while expanding the theoretical framework and methodology of landscape ecology. By emphasizing the dynamic interactions between land planning, construction, and residents' experiences, this study provides valuable insights into the dynamic development of urban green spaces, facilitating the implementation of sustainable urban development strategies and practices.
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2007AA05Z125)
文摘Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands hours even years. In order to achieve a rapid evaluation technique and to seek lifetime extension methods, a lifetime calculation formation was drawn out in consideration of the vehicle driving cycle and the working condition factors. Bench experiments were individually carried out on two fuel-cell stacks same as ones applied on vehicle, and the performance decay rates of the two stacks were obtained under four operation conditions of changing load cycle, start-stop cycle, idling and heavy load. As a result, the predicted lifetimes rather conform to the actual running status in road test. And the research on the fuel cell performance decay rates under different load conditions was also done. Consequently, an unexpected finding was discovered that operating under micro-current has an effect on recovering fuel cell performance. The vehicle fuel cell rapid assessment method only requires four laboratory tests of driving cycle, load cycle, idle operating conditions and heavy load conditions, and the whole process merely lasts less than 250 h. These experimental results can be used to predict the vehicular fuel cell lifetimes on various utility models or driving cycles, therefore to optimize the application model to prolong the fuel cell lifetime. Actually in the experiment, it has already been proved successfully that the fuel cell lifetime could be extended from 1 100 h to 2 600 h by optimizing operating mode. The quick evaluation method is helpful to develop extended life fuel cell and to deplete fuel cell for a longer time.
