Urban internal structure is essential information for urban geography researchers and urban planners or managers. This research aims to examine the spatial structure changes of internal urban land use based on the int...Urban internal structure is essential information for urban geography researchers and urban planners or managers. This research aims to examine the spatial structure changes of internal urban land use based on the interpreted datasets of 1984 and 2008. Spatio-temporal patterns of internal land use conversion and urban expansion are analyzed, and then dominant driving factors (e.g., social economy, population growth and urban planning) were identified. The results indicate that Beijing′s intra-urban layout has experienced tremendous adjustment from compact to disperse configure, otherwise its function objects have shifted from the major economic and industrial development before the 1990s to the combination with cultural, high-technological and inhabitable city at present. The dominant urban land use transformations include the relocation of industrial lands from core districts to suburban or other provinces, and the accelerating expansion of residential areas and green spaces for supplying the demand of housing and ecological protection. Although Beijing′s urban planning has experienced three major adjustments and improvement since the 1980s, its optimization of urban internal patterns still remains a challenge.展开更多
The underlying complexity of urban space can be manifested by its fractal forms and scaling statistics.This paper examines these characteristics at the intra-urban scale through the lens of clustered street junctions(...The underlying complexity of urban space can be manifested by its fractal forms and scaling statistics.This paper examines these characteristics at the intra-urban scale through the lens of clustered street junctions(including road ends)in two Chinese metropolitan areas:Beijing and Shenzhen.We derived the cluster sets with Euclidean distance thresholds starting at 100 meters(m)and ending at 1000 m,and outlined each cluster using a concave-hull method to maintain their original irregular shapes.Within each delimited cluster,we examined four urban attributes:gross domestic product,number of street nodes,polygon area,and population.Our analysis revealed that power law distribution applied to almost every cluster set in terms of the four attributes,but varied from one attribute to another or from city to city,represented primarily byfluctuated power law exponents and ht-index values whose profiles along with the cluster growth can effectively characterize the urban structure.Additionally,we computed the spectrum of intra-urban scaling exponents with cluster size increments,contributing new insights into the allometric relationships between urban configuration and function.展开更多
Background:Dengue fever(DF)is a mosquito-borne infectious disease that has threatened tropical and subtropical regions in recent decades.An early and targeted warning of a dengue epidemic is important for vector contr...Background:Dengue fever(DF)is a mosquito-borne infectious disease that has threatened tropical and subtropical regions in recent decades.An early and targeted warning of a dengue epidemic is important for vector control.Current studies have primarily determined weather conditions to be the main factor for dengue forecasting,thereby neglecting that environmental suitability for mosquito breeding is also an important factor,especially in fine-grained intra-urban settings.Considering that street-view images are promising for depicting physical environments,this study proposes a framework for facilitating fine-grained intra-urban dengue forecasting by integrating the urban environments measured from street-view images.展开更多
To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-lev...To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-level data set of Beijing and employs a distance-based approach, which considers space as continuous. Unlike previous studies, we set two sets of references for service and manufacturing industries respectively to adapt to the investigation in the intra-urban area. Comparing among eight types of industries and different firm sizes, we find that： 1） producer service, high-tech industries and labor-intensive manufacturing industries are more likely to cluster, whereas personal service and capital-intensive industries tend to be randomly dispersed in Beijing; 2） the spillover of the co-location of finns is more important to knowledge-intensive industries and has more significant impact on their allocation than business-oriented services in the intra-urban area; 3） the spatial agglomeration of service industries are driven by larger establishments, whereas manufac- turing industries are mixed.展开更多
基金Under the auspices of Open Fund of State Key Laboratory of Remote Sensing Science (No. 2009KFJJ005)the Young Scientist Fund of National Natural Science Foundation of China (No. 40901224)National Basic Research Program of China (No.2010CB950900)
文摘Urban internal structure is essential information for urban geography researchers and urban planners or managers. This research aims to examine the spatial structure changes of internal urban land use based on the interpreted datasets of 1984 and 2008. Spatio-temporal patterns of internal land use conversion and urban expansion are analyzed, and then dominant driving factors (e.g., social economy, population growth and urban planning) were identified. The results indicate that Beijing′s intra-urban layout has experienced tremendous adjustment from compact to disperse configure, otherwise its function objects have shifted from the major economic and industrial development before the 1990s to the combination with cultural, high-technological and inhabitable city at present. The dominant urban land use transformations include the relocation of industrial lands from core districts to suburban or other provinces, and the accelerating expansion of residential areas and green spaces for supplying the demand of housing and ecological protection. Although Beijing′s urban planning has experienced three major adjustments and improvement since the 1980s, its optimization of urban internal patterns still remains a challenge.
基金supported and funded by the National Natural Science Foundation of China(No.42001180)Shenzhen Science and Technology Program(No.20220809120650001)Guangdong Science and Technology Strategic Inno-vation Fund(the Guangdong Hong Kong-Macao Joint Laboratory Program,No.2020B1212030009).
文摘The underlying complexity of urban space can be manifested by its fractal forms and scaling statistics.This paper examines these characteristics at the intra-urban scale through the lens of clustered street junctions(including road ends)in two Chinese metropolitan areas:Beijing and Shenzhen.We derived the cluster sets with Euclidean distance thresholds starting at 100 meters(m)and ending at 1000 m,and outlined each cluster using a concave-hull method to maintain their original irregular shapes.Within each delimited cluster,we examined four urban attributes:gross domestic product,number of street nodes,polygon area,and population.Our analysis revealed that power law distribution applied to almost every cluster set in terms of the four attributes,but varied from one attribute to another or from city to city,represented primarily byfluctuated power law exponents and ht-index values whose profiles along with the cluster growth can effectively characterize the urban structure.Additionally,we computed the spectrum of intra-urban scaling exponents with cluster size increments,contributing new insights into the allometric relationships between urban configuration and function.
文摘Background:Dengue fever(DF)is a mosquito-borne infectious disease that has threatened tropical and subtropical regions in recent decades.An early and targeted warning of a dengue epidemic is important for vector control.Current studies have primarily determined weather conditions to be the main factor for dengue forecasting,thereby neglecting that environmental suitability for mosquito breeding is also an important factor,especially in fine-grained intra-urban settings.Considering that street-view images are promising for depicting physical environments,this study proposes a framework for facilitating fine-grained intra-urban dengue forecasting by integrating the urban environments measured from street-view images.
基金State Key Program of National Natural Science of China(No.41230632)National Natural Science Foundation of China(No.41301123,41201169)
文摘To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-level data set of Beijing and employs a distance-based approach, which considers space as continuous. Unlike previous studies, we set two sets of references for service and manufacturing industries respectively to adapt to the investigation in the intra-urban area. Comparing among eight types of industries and different firm sizes, we find that： 1） producer service, high-tech industries and labor-intensive manufacturing industries are more likely to cluster, whereas personal service and capital-intensive industries tend to be randomly dispersed in Beijing; 2） the spillover of the co-location of finns is more important to knowledge-intensive industries and has more significant impact on their allocation than business-oriented services in the intra-urban area; 3） the spatial agglomeration of service industries are driven by larger establishments, whereas manufac- turing industries are mixed.
