With the ever increasing population,rapid growth of science and technology,increasing pollution and change in life style put enormous pressure on availability of water and energy for living being.Therefore the present...With the ever increasing population,rapid growth of science and technology,increasing pollution and change in life style put enormous pressure on availability of water and energy for living being.Therefore the present study is done to identify the tools to fight against climate change with the following objectives:(1)to know the water and carbon footprint of the people from rural and urban areas;(2)to know the water lifting devices used展开更多
Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer tra...Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer trajectories. In order to address the usually slow computational time for the determination of the landing footprint of a space-to-ground vehicle under finite thrust, this work proposes a method that uses polynomial equations to describe the boundaries of the landing footprint and uses back propagation(BP) neural networks to quickly determine the landing footprint of the space-to-ground vehicle. First, given orbital parameters and a manoeuvre moment, the solution model of the landing footprint of a space-to-ground vehicle under finite thrust is established. Second, given arbitrary orbital parameters and an arbitrary manoeuvre moment, a fast computational model for the landing footprint of a space-to-ground vehicle based on BP neural networks is provided.Finally, the simulation results demonstrate that under the premise of ensuring accuracy, the proposed method can quickly determine the landing footprint of a space-to-ground vehicle with arbitrary orbital parameters and arbitrary manoeuvre moments. The proposed fast computational method for determining a landing footprint lays a foundation for the parking-orbit configuration and supports the design of real-time transfer trajectories.展开更多
Appraisaling the land-use change degree of urban land objectively, analyzing the reasons, and proposing the countermeasures have important meanings to promote land sustainable development. The article analyzed the dyn...Appraisaling the land-use change degree of urban land objectively, analyzing the reasons, and proposing the countermeasures have important meanings to promote land sustainable development. The article analyzed the dynamic change of land-use ecological footprint in Harbin City from 1996 to 2006. Through the measurement of ecological footprint to assess the social impact and the extent of sustainable land-use. The results showed that the per capita ecological footprint in Harbin had increased year by year, while the per capita ecological carrying capacity had decreased, the per capita ecological deficit was increasing, and land-use in Harbin City was in an overload status. Finally, reasonable land-use proposals were proposed.展开更多
【目的】建立新型室内铺地材料石木塑复合地板生命周期数据集,全面量化石木塑复合地板生产过程的环境影响和生物碳储量,与传统室内铺地材料的环境性能进行对比,提出石木塑复合地板环境性能提升举措并量化其提升潜力,为行业绿色低碳发展...【目的】建立新型室内铺地材料石木塑复合地板生命周期数据集,全面量化石木塑复合地板生产过程的环境影响和生物碳储量,与传统室内铺地材料的环境性能进行对比,提出石木塑复合地板环境性能提升举措并量化其提升潜力,为行业绿色低碳发展提供支撑。【方法】建立石木塑复合地板从摇篮到大门阶段的生命周期模型,并量化其一次能源消耗(PED)、非生物资源消耗潜值(ADP)、全球变暖潜值(GWP)、水资源消耗(WU)、酸化(AP)、富营养化潜值(EP)、可吸入无机物(RI)、臭氧层消耗(ODP)、光化学臭氧合成(POFP)、电离辐射-人体健康(IRP)、生态毒性(ET)等中点环境影响,以及节能减排综合指标(ECER)和生物碳储量。【结果】原材料获取阶段是中点环境指标的最大贡献者,对各指标的贡献度超过63%。地板制造阶段ET的贡献度达35.76%,运输阶段的环境影响较小。1 m^(2)石木塑复合地板从摇篮到大门阶段的ECER为4.12E-11。聚氯乙烯(PVC)和聚乙烯生产过程是原材料获取阶段的主要环境热点,电力、天然气和柴油生产过程是地板制造阶段的主要环境热点。1 m^(2)石木塑复合地板的生物碳储量为0.12 kg CO_(2)eq,占其GWP的1.1%。未来,应提高原料利用效率(节材),降低石木塑复合地板生产过程中PVC、聚乙烯和碳酸钙的消耗量,同时提高能源利用效率(节能),降低地板制造阶段的电耗,以提升石木塑复合地板环境性能。【结论】本研究填补了石木塑复合地板环境性能研究的空白,帮助地板制造商、建筑开发商、设计师、消费者和研究人员等认识石木塑复合地板这一新型铺地材料的综合环境性能,同时提出可操作性的提升举措,可为石木塑复合地板行业绿色低碳发展提供有益参考。展开更多
文摘With the ever increasing population,rapid growth of science and technology,increasing pollution and change in life style put enormous pressure on availability of water and energy for living being.Therefore the present study is done to identify the tools to fight against climate change with the following objectives:(1)to know the water and carbon footprint of the people from rural and urban areas;(2)to know the water lifting devices used
基金supported by the National Natural Science Foundation of China (61603398)。
文摘Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer trajectories. In order to address the usually slow computational time for the determination of the landing footprint of a space-to-ground vehicle under finite thrust, this work proposes a method that uses polynomial equations to describe the boundaries of the landing footprint and uses back propagation(BP) neural networks to quickly determine the landing footprint of the space-to-ground vehicle. First, given orbital parameters and a manoeuvre moment, the solution model of the landing footprint of a space-to-ground vehicle under finite thrust is established. Second, given arbitrary orbital parameters and an arbitrary manoeuvre moment, a fast computational model for the landing footprint of a space-to-ground vehicle based on BP neural networks is provided.Finally, the simulation results demonstrate that under the premise of ensuring accuracy, the proposed method can quickly determine the landing footprint of a space-to-ground vehicle with arbitrary orbital parameters and arbitrary manoeuvre moments. The proposed fast computational method for determining a landing footprint lays a foundation for the parking-orbit configuration and supports the design of real-time transfer trajectories.
基金Supported by China Postdoctoral Fund Project (20060391066)Postdoctoral Fund of Heilongjiang Province (LBH-Q06096)
文摘Appraisaling the land-use change degree of urban land objectively, analyzing the reasons, and proposing the countermeasures have important meanings to promote land sustainable development. The article analyzed the dynamic change of land-use ecological footprint in Harbin City from 1996 to 2006. Through the measurement of ecological footprint to assess the social impact and the extent of sustainable land-use. The results showed that the per capita ecological footprint in Harbin had increased year by year, while the per capita ecological carrying capacity had decreased, the per capita ecological deficit was increasing, and land-use in Harbin City was in an overload status. Finally, reasonable land-use proposals were proposed.
文摘【目的】建立新型室内铺地材料石木塑复合地板生命周期数据集,全面量化石木塑复合地板生产过程的环境影响和生物碳储量,与传统室内铺地材料的环境性能进行对比,提出石木塑复合地板环境性能提升举措并量化其提升潜力,为行业绿色低碳发展提供支撑。【方法】建立石木塑复合地板从摇篮到大门阶段的生命周期模型,并量化其一次能源消耗(PED)、非生物资源消耗潜值(ADP)、全球变暖潜值(GWP)、水资源消耗(WU)、酸化(AP)、富营养化潜值(EP)、可吸入无机物(RI)、臭氧层消耗(ODP)、光化学臭氧合成(POFP)、电离辐射-人体健康(IRP)、生态毒性(ET)等中点环境影响,以及节能减排综合指标(ECER)和生物碳储量。【结果】原材料获取阶段是中点环境指标的最大贡献者,对各指标的贡献度超过63%。地板制造阶段ET的贡献度达35.76%,运输阶段的环境影响较小。1 m^(2)石木塑复合地板从摇篮到大门阶段的ECER为4.12E-11。聚氯乙烯(PVC)和聚乙烯生产过程是原材料获取阶段的主要环境热点,电力、天然气和柴油生产过程是地板制造阶段的主要环境热点。1 m^(2)石木塑复合地板的生物碳储量为0.12 kg CO_(2)eq,占其GWP的1.1%。未来,应提高原料利用效率(节材),降低石木塑复合地板生产过程中PVC、聚乙烯和碳酸钙的消耗量,同时提高能源利用效率(节能),降低地板制造阶段的电耗,以提升石木塑复合地板环境性能。【结论】本研究填补了石木塑复合地板环境性能研究的空白,帮助地板制造商、建筑开发商、设计师、消费者和研究人员等认识石木塑复合地板这一新型铺地材料的综合环境性能,同时提出可操作性的提升举措,可为石木塑复合地板行业绿色低碳发展提供有益参考。
