This paper makes a detailed analysis of the vanous drawbacks of the continued use of adwhnistrative area in dividing urban and rural areas in spite of the serious discrepancies between urban admnistrative boundaries a...This paper makes a detailed analysis of the vanous drawbacks of the continued use of adwhnistrative area in dividing urban and rural areas in spite of the serious discrepancies between urban admnistrative boundaries and the 'real' urban space in China. The autiors believe that to solve this problem, it is essential to establish the concept of physical urban area with both adaptability to Chinese situation and intemational comparability and use it as the basis of urban-rural division and statistics. It is proposed that physical urban area should be defined in terms of prescribed minimum population scale, dngee of nonaghculturalization and population density.Based on extensive substantive research and a classifiotion of the space figurations of Chinese cities and towns, a new scheme to classify physical urban areas is proposed.展开更多
According to the characteristics of sodar echo,a classified method for temperature stratification is given. By using sodar data observed in Yanshan Mountain area in Beijing,the statistical characteristics for the heig...According to the characteristics of sodar echo,a classified method for temperature stratification is given. By using sodar data observed in Yanshan Mountain area in Beijing,the statistical characteristics for the height of inversion layer,thermal plume,and the depth of mixed layer are compared.Finally,the appearance frequency for stable,unstable and neutral stratification is analyzed.展开更多
文摘This paper makes a detailed analysis of the vanous drawbacks of the continued use of adwhnistrative area in dividing urban and rural areas in spite of the serious discrepancies between urban admnistrative boundaries and the 'real' urban space in China. The autiors believe that to solve this problem, it is essential to establish the concept of physical urban area with both adaptability to Chinese situation and intemational comparability and use it as the basis of urban-rural division and statistics. It is proposed that physical urban area should be defined in terms of prescribed minimum population scale, dngee of nonaghculturalization and population density.Based on extensive substantive research and a classifiotion of the space figurations of Chinese cities and towns, a new scheme to classify physical urban areas is proposed.
文摘According to the characteristics of sodar echo,a classified method for temperature stratification is given. By using sodar data observed in Yanshan Mountain area in Beijing,the statistical characteristics for the height of inversion layer,thermal plume,and the depth of mixed layer are compared.Finally,the appearance frequency for stable,unstable and neutral stratification is analyzed.
