Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefor...Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefore,this paper analyzes the spatial interaction between urban scale hierarchy and urban networks in China from 2019 to 2023,drawing on Baidu migration data and employing a spatial simultaneous equation model.The results reveal a significant positive spatial correlation between cities with higher hierarchy and those with greater network centrality.Within a static framework,we identify a positive interaction between urban scale hierarchy and urban network centrality,while their spatial cross-effects manifest as negative neighborhood interactions based on geographical distance and positive cross-scale interactions shaped by network connections.Within a dynamic framework,changes in urban scale hierarchy and urban networks are mutually reinforcing,thereby widening disparities within the urban hierarchy.Furthermore,an increase in a city’s network centrality had a dampening effect on the population growth of neighboring cities and network-connected cities.This study enhances understanding of the spatial organisation of urban systems and offers insights for coordinated regional development.展开更多
The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to eit...The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to either shrinkage or expansion of urban scale.However,research on the influence mechanisms of the urban scale has mostly concentrated on historical,economic and social factors.The influence of traffic factors is rarely mentioned in current research.Therefore,this study examines Northeast China,where the change in urban scale is most significant,to discuss the spatial impact of high-speed railway on the urban scale.This is of great significance in terms of enriching current understanding of the factors affecting the urban scale.The results included the following:1)The high-speed railway produced considerable space-time convergence effects,however,simultaneously aggravated the imbalance in traffic development in Northeast China.The increase in accessibility presents attenuation characteristics from the high-speed railway.Additionally,the high-speed railway has changed the mode of cooperation between cities in the provinces,inter-regional and inter-provincial cooperation models gradually become popular.2)The change rate of accessibility and the urban scale present significant spatial coupling phenomena,with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant.3)There are predominantly four modes of the influence of high-speed railway on the urban scale,which make difference city present expansion or shrinkage.展开更多
Urban sprawl is a critical challenge in the urban development trajectory of developing countries,necessitating precise measurement,trend projection,and strategic management to achieve sustainable urban growth.This stu...Urban sprawl is a critical challenge in the urban development trajectory of developing countries,necessitating precise measurement,trend projection,and strategic management to achieve sustainable urban growth.This study focuses on the Yangtze River Economic Belt(YREB)as a case region and introduces a comprehensive evaluation framework that incorporates multidimensional factors and addresses the scale effects of urban sprawl.We emphasize the value of a systematic geographical approach by quantifying urban sprawl through simulated scenarios and analyzing its driving factors.We constructed an innovative urban sprawl index(USI)to assess the degree of sprawl within the YREB.This assessment integrates two geographic models with an artificial neural network algorithm,enabling simulation of urban sprawl trends under two future scenarios for 2035.Additionally,two analytical methods were employed to identify the key driving mechanisms of urban sprawl in the region.Findings indicate a strong correlation between urban scale and the extent of urban sprawl:larger urban areas exhibit more pronounced sprawl,with agglomeration and morphological transformations identified as primary contributors to urban sprawl.The study further reveals an intricate association between urban sprawl and the compactness of urban internal structures.While both development scenarios offer distinct advantages,the Coordinated Development Scenario is projected to foster a more balanced urban expansion.The robustness of the evaluation framework was enhanced through simulation and an in-depth analysis of internal mechanisms,bolstering confidence in its applicability.We advocate for the adoption and continued refinement of this framework as a tool for promoting balanced urban growth.The strategic recommendations provided herein are vital for mitigating multi-scale urban sprawl,advancing economic development,and improving residents’quality of life across cities in the YREB.展开更多
Across the U.S.,the increasing demand for electric vehicle(EV)charging infrastructure is placing new demands on the power grid,challenging its stability and efficiency.To address these challenges,this study proposes a...Across the U.S.,the increasing demand for electric vehicle(EV)charging infrastructure is placing new demands on the power grid,challenging its stability and efficiency.To address these challenges,this study proposes a Vehicle-to-Building-to-Grid(V2B2G)framework that incorporates urban-scale human mobility modeling to optimize EV charging and discharging.Using anonymized GPS traces from the study community,we extracted individual mobility patterns and applied kernel-density estimation to predict departure and arrival times for each user.The framework was tested in a mixed-use community in Phoenix,Arizona that includes both residential and commercial buildings.A comprehensive decentralized model predictive control(MPC)framework is implemented to minimize energy costs and enhance grid flexibility through demand-side management while maintaining occupant comfort.Four different control strategies were designed and evaluated,the strategy which balances both user and grid benefits demonstrated the best performance,achieving:(1)a flattened grid net load curve,with a 56%reduction in on-peak demand and a 56%decrease in peak load rebound;(2)a 37.96%reduction in grid net load compared to the baseline control;and(3)a 68.05%performance improvement when considering six flexibility factors:cost savings,total-energy reduction,on-peak demand reduction,off-peak demand reduction,load shifting from peak to non-peak hours,and peak-load-rebound reduction.These findings enhance our understanding of the impacts of urban mobility and EV charging optimization on grid management.展开更多
In the United States,the buildings sector consumes about 76%of electricity use and 40% of all primary energy use and associated greenhouse gas emissions.Occupant behavior has drawn increasing research interests due to...In the United States,the buildings sector consumes about 76%of electricity use and 40% of all primary energy use and associated greenhouse gas emissions.Occupant behavior has drawn increasing research interests due to its impacts on the building energy consumption.However,occupant behavior study at urban scale remains a challenge,and very limited studies have been conducted.As an effort to couple big data analysis with human mobility modeling,this study has explored urban scale human mobility utilizing three months Global Positioning System(GPS)data of 93,o00 users at Phoenix Metropolitan Area.This research extracted stay points from raw data,and identified users'home,work,and other locations by Density-Based Spatial Clustering algorithm.Then,daily mobility patterns were constructed using different types of locations.We propose a novel approach to predict urban scale daily human mobility patterns with 12-hour prediction horizon,using Long Short-Term Memory(LSTM)neural network model.Results shows the developed models achieved around 85%average accuracy and about 86%mean precision.The developed models can be further applied to analyze urban scale occupant behavior,building energy demand and flexibility,and contributed to urban planning.展开更多
Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban sca...Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban scale, urban sub-domain scale, and single to few buildings scale. In it, different underlying surface types are employed, the building drag factor is used to replace its roughness in the influence on the urban wind field, the effects of building distribution, azimuth and screening of shortwave radiation are added, and the influence of anthropogenic heating is also taken into account. All the numerical tests indicate that the simulated results are reasonably in agreement with the observational data, so the system can be used to simulate the urban meteorological environment. Making use of it, the characteristics of the meteorological environment from the urban to urban sub-domain scales, even the among-buildings scale, can be recognized. As long as the urban planning scheme is given, the corresponding simulated results can be obtained so as to meet the need of optimizing urban planning.展开更多
The Regional Atmospheric Modeling System （RAMS） and the computational fluid dynamics （CFD） codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer （USL）...The Regional Atmospheric Modeling System （RAMS） and the computational fluid dynamics （CFD） codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer （USL）. RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL.展开更多
Urban faults in Shenzhen are potential threats to city security and sustainable development. In consideration of the importance of the Shenzhen fault zone, the author provide a detailed interpretation on gravity data ...Urban faults in Shenzhen are potential threats to city security and sustainable development. In consideration of the importance of the Shenzhen fault zone, the author provide a detailed interpretation on gravity data model. Bouguer gravity covering the whole Shenzhen City was calculated with a 1-km resolution. Wavelet multi-scale analysis（MSA） was applied to the Bouguer gravity data to obtain the multilayer residual anomalies corresponding to different depths. In addition, 2D gravity models were constructed along three profiles. The Bouguer gravity anomaly shows an NE-striking high-low-high pattern from northwest to southeast, strongly related to the main faults. According to the results of MSA, the correlation between gravity anomaly and faults is particularly significant from 4 to 12 km depth. The residual gravity with small amplitude in each layer indicates weak tectonic activity in the crust. In the upper layers, positive anomalies along most of faults reveal the upwelling of high-density materials during the past tectonic movements. The multilayer residual anomalies also yield important information about the faults, such as the vertical extension and the dip direction. The maximum depth of the faults is about 20 km. In general, NE-striking faults extend deeper than NW-striking faults and have a larger dip angle.展开更多
This paper is to examine the urban and rural construction land data of Dafang between basic year and final year based on country scale and spatial econometrics,and analyze its spatial pattern and change feature. Accor...This paper is to examine the urban and rural construction land data of Dafang between basic year and final year based on country scale and spatial econometrics,and analyze its spatial pattern and change feature. According to the results,the construction lands in all the villages of Dafang County showed strong spatial autocorrelation and significant spatial cluster. After the analysis of local Moran's I,the construction lands in 381 villages of 36 counties presented strong activity. The original small-scale villages were gradually enlarging,which will not only gradually benefit local development,but also be in accordance with the strategy of " one city,one district,eight parks".展开更多
The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis ...The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis （SBM-DEA） has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency （OE） of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency （SE） was higher than the pure technological efficiency （PTE）; PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped＇ trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle展开更多
The efficient development of the urban economy is a major concern of scholars in the fields of geography and urban science.In the context of globalization,informatization,industrialization,and urbanization,the externa...The efficient development of the urban economy is a major concern of scholars in the fields of geography and urban science.In the context of globalization,informatization,industrialization,and urbanization,the external relationships of China's cities are experiencing the joint action of urban scale hierarchies and connection networks(“hierarchy-network”).However,under the interactive effect of the two,the mechanism of urban economic efficiency(UEE)is unclear.Therefore,based on Baidu migration data,the regionalization with dynamically constrained agglomerative clustering and partitioning(REDCAP)method,and a spatial simultaneous equation model,this paper analyzes the UEE spatial pattern and mechanism in China.The results indicate that:(1)the urban economy has a superlinear relationship with the population size.However,the benefit of this superlinear growth is in marginal decline.(2)The UEE shows a pattern of differentiation between China's eastern,then central,and then western region.Also,local differences are found within the three major sub-regions.(3)The increase of urban network centrality can promote UEE,while the impact of urban scale is negative.(4)There is regional heterogeneity of the interactive effect of“hierarchy-network”on UEE.This study reveals the influencing mechanism of UEE and also provides policy implications for the development of UEE.展开更多
The “Monitoring City Walls” research project by the University of Pisa approaches planned conservation as a process that pursues an in-depth understanding of historic city walls and their surroundings to define a sy...The “Monitoring City Walls” research project by the University of Pisa approaches planned conservation as a process that pursues an in-depth understanding of historic city walls and their surroundings to define a system of effective risk prevention. This multidisciplinary research adopts monitoring strategies and technologies at the large scale and in relationship to natural and urban conditions. The underlying logic frames the conservation of these historic fortifications within the more general mitigation of risks generated by context. The research aims to develop an innovative approach to monitoring ancient defensive structures in historical towns. The integrated use of advanced technologies allows for the control and, most importantly, advance identification of possible risks. These new technologies, in particular satellite interferometry, make it possible to improve and increase the operational capacity of monitoring processes by facilitating the acquisition and investigation of data relative to the system defined by ancient city walls and their surroundings. These technologies also represent a cost-effective tool for managing the important transition from the observation and study of individual monuments to the monitoring of large monumental complexes or even entire historical centers.展开更多
基金Under the auspices of the National Natural Science Foundation of China(No.42371222,41971167)Fundamental Scientific Research Funds of Central China Normal University(No.CCNU24ZZ120)。
文摘Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefore,this paper analyzes the spatial interaction between urban scale hierarchy and urban networks in China from 2019 to 2023,drawing on Baidu migration data and employing a spatial simultaneous equation model.The results reveal a significant positive spatial correlation between cities with higher hierarchy and those with greater network centrality.Within a static framework,we identify a positive interaction between urban scale hierarchy and urban network centrality,while their spatial cross-effects manifest as negative neighborhood interactions based on geographical distance and positive cross-scale interactions shaped by network connections.Within a dynamic framework,changes in urban scale hierarchy and urban networks are mutually reinforcing,thereby widening disparities within the urban hierarchy.Furthermore,an increase in a city’s network centrality had a dampening effect on the population growth of neighboring cities and network-connected cities.This study enhances understanding of the spatial organisation of urban systems and offers insights for coordinated regional development.
基金Under the auspices of National Natural Science Foundation of China(No.41471133,41871112).
文摘The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to either shrinkage or expansion of urban scale.However,research on the influence mechanisms of the urban scale has mostly concentrated on historical,economic and social factors.The influence of traffic factors is rarely mentioned in current research.Therefore,this study examines Northeast China,where the change in urban scale is most significant,to discuss the spatial impact of high-speed railway on the urban scale.This is of great significance in terms of enriching current understanding of the factors affecting the urban scale.The results included the following:1)The high-speed railway produced considerable space-time convergence effects,however,simultaneously aggravated the imbalance in traffic development in Northeast China.The increase in accessibility presents attenuation characteristics from the high-speed railway.Additionally,the high-speed railway has changed the mode of cooperation between cities in the provinces,inter-regional and inter-provincial cooperation models gradually become popular.2)The change rate of accessibility and the urban scale present significant spatial coupling phenomena,with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant.3)There are predominantly four modes of the influence of high-speed railway on the urban scale,which make difference city present expansion or shrinkage.
基金supported by the National Natural Science Foundation of China(Grant No.U24A20580)National Natural Science Foundation of China(Grant No.42171298)+1 种基金Natural Science Foundation of Chongqing,China(Grant No.CSTB2023NSCQLZX0009)Philosophy and Social Science Major Project of Chongqing Municipal Education Commission(Grant No.24SKZDZX04).
文摘Urban sprawl is a critical challenge in the urban development trajectory of developing countries,necessitating precise measurement,trend projection,and strategic management to achieve sustainable urban growth.This study focuses on the Yangtze River Economic Belt(YREB)as a case region and introduces a comprehensive evaluation framework that incorporates multidimensional factors and addresses the scale effects of urban sprawl.We emphasize the value of a systematic geographical approach by quantifying urban sprawl through simulated scenarios and analyzing its driving factors.We constructed an innovative urban sprawl index(USI)to assess the degree of sprawl within the YREB.This assessment integrates two geographic models with an artificial neural network algorithm,enabling simulation of urban sprawl trends under two future scenarios for 2035.Additionally,two analytical methods were employed to identify the key driving mechanisms of urban sprawl in the region.Findings indicate a strong correlation between urban scale and the extent of urban sprawl:larger urban areas exhibit more pronounced sprawl,with agglomeration and morphological transformations identified as primary contributors to urban sprawl.The study further reveals an intricate association between urban sprawl and the compactness of urban internal structures.While both development scenarios offer distinct advantages,the Coordinated Development Scenario is projected to foster a more balanced urban expansion.The robustness of the evaluation framework was enhanced through simulation and an in-depth analysis of internal mechanisms,bolstering confidence in its applicability.We advocate for the adoption and continued refinement of this framework as a tool for promoting balanced urban growth.The strategic recommendations provided herein are vital for mitigating multi-scale urban sprawl,advancing economic development,and improving residents’quality of life across cities in the YREB.
基金supported by the U.S.National Science Foundation(Award No.1949372).
文摘Across the U.S.,the increasing demand for electric vehicle(EV)charging infrastructure is placing new demands on the power grid,challenging its stability and efficiency.To address these challenges,this study proposes a Vehicle-to-Building-to-Grid(V2B2G)framework that incorporates urban-scale human mobility modeling to optimize EV charging and discharging.Using anonymized GPS traces from the study community,we extracted individual mobility patterns and applied kernel-density estimation to predict departure and arrival times for each user.The framework was tested in a mixed-use community in Phoenix,Arizona that includes both residential and commercial buildings.A comprehensive decentralized model predictive control(MPC)framework is implemented to minimize energy costs and enhance grid flexibility through demand-side management while maintaining occupant comfort.Four different control strategies were designed and evaluated,the strategy which balances both user and grid benefits demonstrated the best performance,achieving:(1)a flattened grid net load curve,with a 56%reduction in on-peak demand and a 56%decrease in peak load rebound;(2)a 37.96%reduction in grid net load compared to the baseline control;and(3)a 68.05%performance improvement when considering six flexibility factors:cost savings,total-energy reduction,on-peak demand reduction,off-peak demand reduction,load shifting from peak to non-peak hours,and peak-load-rebound reduction.These findings enhance our understanding of the impacts of urban mobility and EV charging optimization on grid management.
基金supported by the U.S.National Science Foundation(Award No.1949372 and No.2125775)in part supported through computational resources provided by Syracuse University.
文摘In the United States,the buildings sector consumes about 76%of electricity use and 40% of all primary energy use and associated greenhouse gas emissions.Occupant behavior has drawn increasing research interests due to its impacts on the building energy consumption.However,occupant behavior study at urban scale remains a challenge,and very limited studies have been conducted.As an effort to couple big data analysis with human mobility modeling,this study has explored urban scale human mobility utilizing three months Global Positioning System(GPS)data of 93,o00 users at Phoenix Metropolitan Area.This research extracted stay points from raw data,and identified users'home,work,and other locations by Density-Based Spatial Clustering algorithm.Then,daily mobility patterns were constructed using different types of locations.We propose a novel approach to predict urban scale daily human mobility patterns with 12-hour prediction horizon,using Long Short-Term Memory(LSTM)neural network model.Results shows the developed models achieved around 85%average accuracy and about 86%mean precision.The developed models can be further applied to analyze urban scale occupant behavior,building energy demand and flexibility,and contributed to urban planning.
基金sponsored by the Key Project(96-920-34-07)of the Ministry of Science and Technology,Chinathe Nationa1 Natura1 Science Foundation of China(40333027).
文摘Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban scale, urban sub-domain scale, and single to few buildings scale. In it, different underlying surface types are employed, the building drag factor is used to replace its roughness in the influence on the urban wind field, the effects of building distribution, azimuth and screening of shortwave radiation are added, and the influence of anthropogenic heating is also taken into account. All the numerical tests indicate that the simulated results are reasonably in agreement with the observational data, so the system can be used to simulate the urban meteorological environment. Making use of it, the characteristics of the meteorological environment from the urban to urban sub-domain scales, even the among-buildings scale, can be recognized. As long as the urban planning scheme is given, the corresponding simulated results can be obtained so as to meet the need of optimizing urban planning.
基金This study was supported by the National Natural Science Foundation of China （Grant Nos. 40233030, 40405004, 40405014）.
文摘The Regional Atmospheric Modeling System （RAMS） and the computational fluid dynamics （CFD） codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer （USL）. RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL.
基金supported by the National Natural Science Foundation of China (Nos.41504015,41429401)the National 973 Project of China (No.2013CB733302)+2 种基金 China Postdoctoral Science Foundation (No.2015M572146)the National High Technology Research and Development Program of China (No.2011AA060503)the Surveying and Mapping Basic Research Program of National Administration of Surveying,Mapping and Geoinformation (No.15-01-08)
文摘Urban faults in Shenzhen are potential threats to city security and sustainable development. In consideration of the importance of the Shenzhen fault zone, the author provide a detailed interpretation on gravity data model. Bouguer gravity covering the whole Shenzhen City was calculated with a 1-km resolution. Wavelet multi-scale analysis（MSA） was applied to the Bouguer gravity data to obtain the multilayer residual anomalies corresponding to different depths. In addition, 2D gravity models were constructed along three profiles. The Bouguer gravity anomaly shows an NE-striking high-low-high pattern from northwest to southeast, strongly related to the main faults. According to the results of MSA, the correlation between gravity anomaly and faults is particularly significant from 4 to 12 km depth. The residual gravity with small amplitude in each layer indicates weak tectonic activity in the crust. In the upper layers, positive anomalies along most of faults reveal the upwelling of high-density materials during the past tectonic movements. The multilayer residual anomalies also yield important information about the faults, such as the vertical extension and the dip direction. The maximum depth of the faults is about 20 km. In general, NE-striking faults extend deeper than NW-striking faults and have a larger dip angle.
基金Supported by the Land Use Plan Program of Dafang Bureau of Land and Resources[(2010)BCXY1209]the Sub-program"Graphics Construction in Dafang County"of the Land Use Plan in Dafang County of School of Economics,Guizhou University[(2011)1201]
文摘This paper is to examine the urban and rural construction land data of Dafang between basic year and final year based on country scale and spatial econometrics,and analyze its spatial pattern and change feature. According to the results,the construction lands in all the villages of Dafang County showed strong spatial autocorrelation and significant spatial cluster. After the analysis of local Moran's I,the construction lands in 381 villages of 36 counties presented strong activity. The original small-scale villages were gradually enlarging,which will not only gradually benefit local development,but also be in accordance with the strategy of " one city,one district,eight parks".
基金Key Research Program of Chinese Academy of Sciences(No.KZZD-EW-06-03-03)
文摘The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis （SBM-DEA） has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency （OE） of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency （SE） was higher than the pure technological efficiency （PTE）; PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped＇ trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle
基金National Natural Science Foundation of China,No.42371222,No.41971167Fundamental Scientific Research Funds of Central China Normal University,No.CCNU24ZZ120,No.CCNU22JC026。
文摘The efficient development of the urban economy is a major concern of scholars in the fields of geography and urban science.In the context of globalization,informatization,industrialization,and urbanization,the external relationships of China's cities are experiencing the joint action of urban scale hierarchies and connection networks(“hierarchy-network”).However,under the interactive effect of the two,the mechanism of urban economic efficiency(UEE)is unclear.Therefore,based on Baidu migration data,the regionalization with dynamically constrained agglomerative clustering and partitioning(REDCAP)method,and a spatial simultaneous equation model,this paper analyzes the UEE spatial pattern and mechanism in China.The results indicate that:(1)the urban economy has a superlinear relationship with the population size.However,the benefit of this superlinear growth is in marginal decline.(2)The UEE shows a pattern of differentiation between China's eastern,then central,and then western region.Also,local differences are found within the three major sub-regions.(3)The increase of urban network centrality can promote UEE,while the impact of urban scale is negative.(4)There is regional heterogeneity of the interactive effect of“hierarchy-network”on UEE.This study reveals the influencing mechanism of UEE and also provides policy implications for the development of UEE.
基金Thanks to Jacinto E.Canivell Garcia De Paredes,Emilio Jose Mascort Albea and Rocio Romero Hernandez at the University of Seville for the support provided in defining the digital mapping instruments.
文摘The “Monitoring City Walls” research project by the University of Pisa approaches planned conservation as a process that pursues an in-depth understanding of historic city walls and their surroundings to define a system of effective risk prevention. This multidisciplinary research adopts monitoring strategies and technologies at the large scale and in relationship to natural and urban conditions. The underlying logic frames the conservation of these historic fortifications within the more general mitigation of risks generated by context. The research aims to develop an innovative approach to monitoring ancient defensive structures in historical towns. The integrated use of advanced technologies allows for the control and, most importantly, advance identification of possible risks. These new technologies, in particular satellite interferometry, make it possible to improve and increase the operational capacity of monitoring processes by facilitating the acquisition and investigation of data relative to the system defined by ancient city walls and their surroundings. These technologies also represent a cost-effective tool for managing the important transition from the observation and study of individual monuments to the monitoring of large monumental complexes or even entire historical centers.
