压缩空气储能(Compressed Air Energy Storage,CAES)具有建设成本低、寿命长、容量大和存储方便等特点,部署在综合能源微网中有助于提升系统的经济性、清洁性和可靠性.但是,CAES具有多能流耦合、结构机理复杂、多种规律并存等特点,给微...压缩空气储能(Compressed Air Energy Storage,CAES)具有建设成本低、寿命长、容量大和存储方便等特点,部署在综合能源微网中有助于提升系统的经济性、清洁性和可靠性.但是,CAES具有多能流耦合、结构机理复杂、多种规律并存等特点,给微网的安全可靠供能提出了更高要求.为分析CAES对综合能源微网可靠性的影响,文中提出了一种计及压缩空气储能的综合能源微网可靠性评估方法.首先针对含CAES的典型综合能源微网,构建了热力系统、CAES系统和分布式电源的物理模型;然后,提出了基于影响增量的含CAES综合能源微网可靠性高效评估方法,大大提升了传统状态枚举的可靠性评估效率;最后,通过我国青海某农业示范园区的实际系统算例,验证了所提方法的有效性和实用性.展开更多
With the rapid development of economy and motorization, the traffic congestion and environmental problems have become more and more serious day by day in Beijing. Therefore, traffic control policies have been graduall...With the rapid development of economy and motorization, the traffic congestion and environmental problems have become more and more serious day by day in Beijing. Therefore, traffic control policies have been gradually adopted by Beijing municipal government since 2008, so as to ease traffic and environmental problems. In this paper, the background and current situation of Beijing to implement traffic control policies are introduced, and also this measure is analyzed and evaluated from traffic effect, environmental effect, motor vehicle development, urban road development, public transport development, and balance between supply and demand, etc. Finally, related conclusions are drawn up as follows: an induced traffic volume will be generated by traffic control policies, and the effect of the traffic control will be erased by the natural growth rate of motor vehicles in three years; public traffic service should be improved for better making traffic control policies; the traffic congestion and environmental problems are alleviated by traffic control policies in the short term, but can't be fundamentally solved in the long run; traffic control policies should cooperate with other traffic demand management policies for reducing demands, and traffic condition should be optimized in both time and space, so that the traffic congestion and environmental problems will be fundamentally solved.展开更多
Evaluating cloud seeding effects is one of the most critical issues in artificial precipitation enhancement experiments. However, the evaluation is not straightforward because there is natural rainfall variability, wh...Evaluating cloud seeding effects is one of the most critical issues in artificial precipitation enhancement experiments. However, the evaluation is not straightforward because there is natural rainfall variability, which subjects the atmosphere to spatiotemporal instabilities. The aim of this study is to analyze natural rainfall variability using the modern statistical simulation method, "bootstrap", to analyze its influence on the evaluation of seeding activities and to take proper measures to control the influence. The study is based on the 1997?2007 airborne seeding macro records and the daily precipitation data in Jilin Province. The influence of natural rainfall variability can be reduced through three approaches: the increase of the supposed "seeded" sample size N, the rejection of outliers, and the selection of similar control units. A larger N leads to smaller calculated precipitation variability and detectable lower limits of seeding effects. When N is near 470 and the seeding effect is between 20% and 30%, the confidence level reaches 90%. For a single seeding operation, the case deletion model that rejects strong influence points and selects similar control units is established to control the influence of natural precipitation variability, which obviously improves the evaluation of artificial precipitation enhancement. The results demonstrate that the relative seeding effect in Jilin Province is concentrated mainly in the range of 0 to 30%, with an average of 11.95%, and has no significant linear relationship with the actual precipitation amount. However, the fluctuation amplitude of the relative effect decreases as the precipitation amount rises.展开更多
文摘压缩空气储能(Compressed Air Energy Storage,CAES)具有建设成本低、寿命长、容量大和存储方便等特点,部署在综合能源微网中有助于提升系统的经济性、清洁性和可靠性.但是,CAES具有多能流耦合、结构机理复杂、多种规律并存等特点,给微网的安全可靠供能提出了更高要求.为分析CAES对综合能源微网可靠性的影响,文中提出了一种计及压缩空气储能的综合能源微网可靠性评估方法.首先针对含CAES的典型综合能源微网,构建了热力系统、CAES系统和分布式电源的物理模型;然后,提出了基于影响增量的含CAES综合能源微网可靠性高效评估方法,大大提升了传统状态枚举的可靠性评估效率;最后,通过我国青海某农业示范园区的实际系统算例,验证了所提方法的有效性和实用性.
基金National Natural Science Foundation of China (Youth Foundation): Study on the Operating Efficiency and Energy Consumption Optimization Methods of the Regional Passenger Transport System (71201006) (Xuesong FENG)
文摘With the rapid development of economy and motorization, the traffic congestion and environmental problems have become more and more serious day by day in Beijing. Therefore, traffic control policies have been gradually adopted by Beijing municipal government since 2008, so as to ease traffic and environmental problems. In this paper, the background and current situation of Beijing to implement traffic control policies are introduced, and also this measure is analyzed and evaluated from traffic effect, environmental effect, motor vehicle development, urban road development, public transport development, and balance between supply and demand, etc. Finally, related conclusions are drawn up as follows: an induced traffic volume will be generated by traffic control policies, and the effect of the traffic control will be erased by the natural growth rate of motor vehicles in three years; public traffic service should be improved for better making traffic control policies; the traffic congestion and environmental problems are alleviated by traffic control policies in the short term, but can't be fundamentally solved in the long run; traffic control policies should cooperate with other traffic demand management policies for reducing demands, and traffic condition should be optimized in both time and space, so that the traffic congestion and environmental problems will be fundamentally solved.
基金supported by the National Meteorological Public Benefit Research Foundation(Grant No.GYHY201006031)the China Meteorological Administration Soft Science Project(Grant No.2012-053)+1 种基金the Jiangsu Province Science Department Grant(Grant No.CB10X_295Z)the Jiangsu Province Qinglan Project for Cloud Fog Precipitation and Aerosol Research Group
文摘Evaluating cloud seeding effects is one of the most critical issues in artificial precipitation enhancement experiments. However, the evaluation is not straightforward because there is natural rainfall variability, which subjects the atmosphere to spatiotemporal instabilities. The aim of this study is to analyze natural rainfall variability using the modern statistical simulation method, "bootstrap", to analyze its influence on the evaluation of seeding activities and to take proper measures to control the influence. The study is based on the 1997?2007 airborne seeding macro records and the daily precipitation data in Jilin Province. The influence of natural rainfall variability can be reduced through three approaches: the increase of the supposed "seeded" sample size N, the rejection of outliers, and the selection of similar control units. A larger N leads to smaller calculated precipitation variability and detectable lower limits of seeding effects. When N is near 470 and the seeding effect is between 20% and 30%, the confidence level reaches 90%. For a single seeding operation, the case deletion model that rejects strong influence points and selects similar control units is established to control the influence of natural precipitation variability, which obviously improves the evaluation of artificial precipitation enhancement. The results demonstrate that the relative seeding effect in Jilin Province is concentrated mainly in the range of 0 to 30%, with an average of 11.95%, and has no significant linear relationship with the actual precipitation amount. However, the fluctuation amplitude of the relative effect decreases as the precipitation amount rises.