Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines ...Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field.展开更多
In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-qualit...In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-quality urban development and continuously meet people’s growing aspirations for a better life.Wuhu,in central China’s Anhui Province,has consistently enhanced its urban functions and services to build a modern,people-oriented city that is innovative,livable,beautiful,resilient,and smart.展开更多
Enhancing urban ecological resilience(UER)is a new concept for modern tourism-oriented cities to cope with environmental crises.Revealing the impact of the urbanization on UER is critical to the sustainability of urba...Enhancing urban ecological resilience(UER)is a new concept for modern tourism-oriented cities to cope with environmental crises.Revealing the impact of the urbanization on UER is critical to the sustainability of urban ecosystems.Taking Zhangjiajie,a typical tourism-oriented city,as an example,urbanization level(UL)and UER evaluation system were constructed,and the change trend was analyzed.The Granger Causality Test model was used to discuss the relationship between UL and UER.The results showed that:(1)the urbanization rate of Zhangjiajie significantly increased by 0.531 from 2011 to 2020.Cili county has the highest UL,and Wulingyuan district including a large number of scenic spots has the fastest development trend.(2)The ecological restoration was more sensitive in the face of rising pressure,and showed a synchronized change trend with pressure.The high pressure in 2016 had the most significant impact on resistance.This effect continued into 2019,with an average decline in resistance of 0.802.(3)The UL has significantly promoted the improvement of urban ecological restoration.Specially,tourism urbanization was the most significant in scenic spots,while economic and social urbanization played a major role in other regions for the improvement of ecological restoration.展开更多
China is carving out a distinctive development path which features urban-rural integration.This approach has not only yielded tangible results domestically but also drawn the attention of other countries.
The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack o...The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack of sanitation facilities.The project,targeting 14,082 households,started last year.展开更多
Traffic at urban intersections frequently encounters unexpected obstructions,resulting in congestion due to uncooperative and priority-based driving behavior.This paper presents an optimal right-turn coordination syst...Traffic at urban intersections frequently encounters unexpected obstructions,resulting in congestion due to uncooperative and priority-based driving behavior.This paper presents an optimal right-turn coordination system for Connected and Automated Vehicles(CAVs)at single-lane intersections,particularly in the context of left-hand side driving on roads.The goal is to facilitate smooth right turns for certain vehicles without creating bottlenecks.We consider that all approaching vehicles share relevant information through vehicular communications.The Intersection Coordination Unit(ICU)processes this information and communicates the optimal crossing or turning times to the vehicles.The primary objective of this coordination is to minimize overall traffic delays,which also helps improve the fuel consumption of vehicles.By considering information from upcoming vehicles at the intersection,the coordination system solves an optimization problem to determine the best timing for executing right turns,ultimately minimizing the total delay for all vehicles.The proposed coordination system is evaluated at a typical urban intersection,and its performance is compared to traditional traffic systems.Numerical simulation results indicate that the proposed coordination system significantly enhances the average traffic speed and fuel consumption compared to the traditional traffic system in various scenarios.展开更多
Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the...Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study.展开更多
The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often...The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often advanced one dimension—such as Internet of Things(IoT)-based data acquisition,Artificial Intelligence(AI)-driven analytics,or digital twin visualization—without fully integrating these strands into a single operational loop.As a result,many existing solutions encounter bottlenecks in responsiveness,interoperability,and scalability,while also leaving concerns about data privacy unresolved.This research introduces a hybrid AI–IoT–Digital Twin framework that combines continuous sensing,distributed intelligence,and simulation-based decision support.The design incorporates multi-source sensor data,lightweight edge inference through Convolutional Neural Networks(CNN)and Long ShortTerm Memory(LSTM)models,and federated learning enhanced with secure aggregation and differential privacy to maintain confidentiality.A digital twin layer extends these capabilities by simulating city assets such as traffic flows and water networks,generating what-if scenarios,and issuing actionable control signals.Complementary modules,including model compression and synchronization protocols,are embedded to ensure reliability in bandwidth-constrained and heterogeneous urban environments.The framework is validated in two urban domains:traffic management,where it adapts signal cycles based on real-time congestion patterns,and pipeline monitoring,where it anticipates leaks through pressure and vibration data.Experimental results show a 28%reduction in response time,a 35%decrease in maintenance costs,and a marked reduction in false positives relative to conventional baselines.The architecture also demonstrates stability across 50+edge devices under federated training and resilience to uneven node participation.The proposed system provides a scalable and privacy-aware foundation for predictive urban infrastructure management.By closing the loop between sensing,learning,and control,it reduces operator dependence,enhances resource efficiency,and supports transparent governance models for emerging smart cities.展开更多
The gap between the projected urban areas in the current trend(UAC)and those in the sustainable scenario(UAS)is a critical factor in understanding whether cities can fulfill the requirements of sustainable development...The gap between the projected urban areas in the current trend(UAC)and those in the sustainable scenario(UAS)is a critical factor in understanding whether cities can fulfill the requirements of sustainable development.However,there is a paucity of knowledge on this cutting-edge topic.Given the extensive and rapid urbanization in the United States(U.S.)over the past two centuries,accurately measuring this gap between UAS and UAC is of critical importance for advancing future sustainable urban development,as well as having significant global implications.This study finds that although the 740 U.S.cities have a large UAC in 2100,these cities will encom pass a significant gap from UAC to UAS(approximately 165,000 km2),accounting for 30%UAC at that time.The study also reveals the spatio-temporal heterogeneity of the gap.The gap initially increases before reaching a inflection point in 2090,and it disparates greatly from−100%to 240%at city level.While cities in the Northwestern U.S.maintain UAC that exceeds UAS from 2020 to 2100,cities in other regions shift from UAC that exceeds UAS to UAC that falls short of UAS.Filling the gap without additional urban growth planning could lead to a reduction of crop production ranging from 0.3%to 3%and a 0.68%loss of biomass.Hence,dynamic and forward-looking urban planning is essential for addressing the challenges of sustainable development posed by urbanization,both within the U.S.and globally.展开更多
This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models ...This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models offer insights, they fall short in presenting a holistic view of complex urban challenges. System dynamics (SD) models that are often utilized to provide holistic, systematic understanding of a research subject, like the urban system, emerge as valuable tools, but data scarcity and theoretical inadequacy pose challenges. The research reviews relevant papers on recent SD model applications in urban sustainability since 2018, categorizing them based on nine key indicators. Among the reviewed papers, data limitations and model assumptions were identified as ma jor challenges in applying SD models to urban sustainability. This led to exploring the transformative potential of big data analytics, a rare approach in this field as identified by this study, to enhance SD models’ empirical foundation. Integrating big data could provide data-driven calibration, potentially improving predictive accuracy and reducing reliance on simplified assumptions. The paper concludes by advocating for new approaches that reduce assumptions and promote real-time applicable models, contributing to a comprehensive understanding of urban sustainability through the synergy of big data and SD models.展开更多
Dryland regions face complex interactions between urbanization and ecological changes,where effective coordination is essential for enhancing sustainability and resilience.However,most studies concentrate on the natio...Dryland regions face complex interactions between urbanization and ecological changes,where effective coordination is essential for enhancing sustainability and resilience.However,most studies concentrate on the national or provincial scales,with insufficient research on county-level coordination,limiting the ability to provide targeted polifrom a precise perspective.This study addresses this gap by analyzing 39 counties within the Hohhot-Baotou-Ordos-Yulin Urban Agglomeration(HBOYUA),a typical dryland urban cluster in China.We use daytime and nighttime remote sensing images to track the spatio-temporal evolution of urbanization and ecological conditions from 1992 to 2023.A novel quantitative framework based on an improved coupling coordination degree(CCD)is proposed to assess their coordination relationship.The results reveal that:(1)Urbanization and ecological quality both exhibited fluctuating upward trends,with spatial heterogeneity increasing for urbanization and decreasing for the eco-environment.Regions with better ecological conditions had higher urbanization levels.(2)The overall coordinated level improved from imbalance(0.36)to low-level coordination(0.55),although its spatial distribution remained uneven,with central urban areas showing higher CCD than surrounding counties.(3)Socioeconomic factors exerted greater effects on CCD than natural factors,with GDP and land surface temperature(LST)playing a significant role in interaction analysis.(4)In western arid regions,urbanization did not necessarily harm ecosystems;instead,ecological conditions improved alongside urbanization.This research offers targeted and valuable references for county and city governments in resource allocation and sustainable development.The proposed methodology is also adaptable for urban resilience studies in other regions.展开更多
Urbanization in small-and medium-sized cities has often been overlooked in urban studies.Research on urbanization has predominantly focused on large metropolitan cities;however,urbanization in small-and medium-sized c...Urbanization in small-and medium-sized cities has often been overlooked in urban studies.Research on urbanization has predominantly focused on large metropolitan cities;however,urbanization in small-and medium-sized cities also contributes to the acceleration of urban sprawl.Urban growth boundary(UGB)is an ecological approach designed to limit urban development.This study aimedto analyze environmental protection priority zonesby combining ecological quality and sensitivity indices to identify the areas suitable for UGB implementation.Tegal City and its surrounding areas(including Tegal and Brebes regencies)of Indonesia were selected as the study area.The ecological quality index was calculated using the normalized difference vegetation index,humidity index,land surface temperature,and normalized difference bare soil index.These indices were subsequently subjected to principal component analysis(PCA)to extract orthogonal factors,which were summed to derive the final index value.In parallel,we mapped and evaluated ecological sensitivity based on spatial planning policies and regulations.The results revealed that ecological quality in Tegal and Brebes regencies was predominantly categorized as good and very good ecological quality,whereas TegalCity exhibited moderate and poor ecological quality.Additionally,over 45.00%of the area in Tegal and Brebes regencies demonstrated very high ecological sensitivity.Consequently,more than 50.00%of the area in Tegal and Brebes regencies,along with 27.00%of Tegal City,were classified as ecological constraint zone,making them potential regionsfor UGB development.The UGB is expected to curtail urban expansion,promote compact city planning,and preserve ecosystem services to achieve urban sustainability.This study implies that planningsmall-and medium-sized cities is important to prevent urban sprawl and maintain environmental health.Designing UGB to limit urban expansion should be enhanced by better knowledge about its ecological functions in supporting urban sustainability.展开更多
Urban memory is the soul and vitality of the city, which is created and maintained by people’s memory of the living environment. However, urban planning and architecture increasingly lose attention to urban memory, r...Urban memory is the soul and vitality of the city, which is created and maintained by people’s memory of the living environment. However, urban planning and architecture increasingly lose attention to urban memory, resulting in the loss of uniqueness of urban appearance, and then affect people’s sense of identity of the city. Therefore, using the theory of typology for reference, a new design tool - urban memory typology is proposed, which focuses on and introduces historical elements into urban design, and maintains urban memory through the protection of cultural heritage. This method involves clarifying the intrinsic relationship between existing buildings and urban space through typology theory, identifying carriers of urban memory, and, on this basis, proposing strategies and technologies for urban renewal. This study verifies the validity of urban memory typology through case analysis, such as the conservation planning of Qingdao Old city. The results show that using the typology theory can protect the city memory, maintain the stability of the city form, and enhance the local identity of the residents, which is a new method of urban planning and design in line with the concept of humanistic care and sustainable development. This research work provides new theoretical guidance and practical strategies for the protection of urban memory and urban planning and design.展开更多
To adapt to national climate change strategies,understanding the thermal vulnerability of urban functional zones(UFZs)is critical for enhancing the livability and sustainable development of cities.We address the limit...To adapt to national climate change strategies,understanding the thermal vulnerability of urban functional zones(UFZs)is critical for enhancing the livability and sustainable development of cities.We address the limitations of existing thermal vulnerability assessments by incorporating human perception into the analysis.Specifically,we introduce the sky openness index to reflect human perception of the thermal environment and examine variations in thermal vulnerability across different UFZs.Using the Extreme Gradient Boosting(XGBoost)-SHapley Additive exPlanations(SHAP)model,we analyze the contributions of 2D and 3D urban form indicators to thermal vulnerability and link these contributions to the unique needs and vulnerability characteristics of UFZs of Foshan City,China in 2023.The results reveal that:1)high-value heat-fragile areas(1.74–2.00]constitute 10.42%of Foshan City;2)traffic zone and publiccommercial zone exhibit the highest levels of thermal vulnerability;and 3)building height and the normalized building index are the most influential factors,with contributions of|0.06|and|0.03|,respectively.We provide a scientific foundation for developing governance strategies to promote urban resilience.展开更多
The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to inv...The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to investigate the impacts of urbanization on ESV in China.However,a comprehensive and dynamic framework to reveal the relationship between ESV and urbanization processes is lacking.This study adopted multi-source datasets to portray China’s urbanization process by integrating population,land,and economic urbanization,eval-uated the ESV changes of 10 categories by gross ecosystem product(GEP)methods,and explored ESV changes within different urbanization scales and speeds.The results showed rapid urbanization in the population,land,and economic dimensions in China,with a faster process of economic urbanization.The ESV also exhibited an increasing trend,with higher levels in the southeastern coastal regions and lower levels in the northwestern regions.Urbanization had positive impacts on ESV across various research units,but the ESV exhibited heteroge-neous changes across different urbanization scales,speeds,and their interactive effects.The response of ESV to dynamic urbanization processes was influenced by socio-economic,ecological,and policy factors;it is essential to combine targeted measures with general ecological product value realization methods in each unit to maximize social-economic-ecological benefits.展开更多
Urban environments offer a wealth of opportunities for residents to respite from their hectic life.Outdoor running or jogging becomes increasingly popular of an option.Impacts of urban environments on outdoor running,...Urban environments offer a wealth of opportunities for residents to respite from their hectic life.Outdoor running or jogging becomes increasingly popular of an option.Impacts of urban environments on outdoor running,despite some initial studies,remain underexplored.This study aims to establish an analytical framework that can holistically assess the urban environment on the healthy vitality of running.The proposed framework is applied to two modern Chinese cities,i.e.,Guangzhou and Shenzhen.We construct three interpretable random forest models to explore the non-linear relationship between environmental variables and running intensity(RI)through analyzing the runners'trajectories and integrating with multi-source urban big data(e.g.,street view imagery,remote sensing,and socio-economic data)across the built,natural,and social dimensions,The findings uncover that road density has the greatest impact on RI,and social variables(e.g.,population density and housing price)and natural variables(e.g.,slope and humidity)all make notable impact on outdoor running.Despite these findings,the impact of environmental variables likely change across different regions due to disparate regional construction and micro-environments,and those specific impacts as well as optimal thresholds also alter.Therefore,construction of healthy cities should take the whole urban environment into account and adapt to local conditions.This study provides a comprehensive evaluation on the influencing variables of healthy vitality and guides sustainable urban planning for creating running-friendly cities.展开更多
Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept o...Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept of urban seismic resilience(USR),its assessment is a large-scale system engineering issue.The assessment of USR should be based on the notion of urban seismic capacity(USC)assessment,which includes casualties,economic loss,and recovery time as criteria.Functionality loss is also included in the assessment of USR in addition to these criteria.The assessment indicator system comprising five dimensions(building and lifeline infrastructure,environment,society,economy,and institution)and 20 indicators has been devised to quantify USR.The analytical hierarchy process(AHP)is utilized to compute the weights of the criteria,dimensions,and indicators in the urban seismic resilience assessment(USRA)indicator system.When the necessary data for a city are obtainable,the seismic resilience of that city can be assessed using this framework.To illustrate the proposed methodology,a moderate-sized city in China was selected as a case study.The assessment results indicate a high level of USR,suggesting that the city possesses strong capabilities to withstand and recover from potential future earthquakes.展开更多
The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic ...The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system.展开更多
Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their ...Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their diversity in urban wetlands reflects the response of wildlife to urbanization.However,very few studies have investigated seasonal differences in the multidimensional diversity of waterbirds in urbanized landscapes.In this study,we analyzed various wetland parameters that could potentially affect the seasonal variations in multidimensional diversity of waterbirds in Nanjing,China.We surveyed waterbirds in 29 urban wetlands using the point count method during breeding and non-breeding seasons from November 2022 to June 2023.We then employed multiple linear regressions and information-theoretic approaches to investigate the impact of wetland characteristics on waterbird diversity.We found that water body area and buffer zone connectivity consistently emerged as positive factors affecting waterbird taxonomic and phylogenetic diversity across seasons.Conversely,the urbanization synthetic index was negatively correlated with waterbird diversity only during the breeding season.Regarding functional diversity,we found that the positive correlation between buffer zone connectivity and waterbird diversity was specific to the breeding season.Therefore,for effective conservation of waterbird diversity in our system,wetland planning should prioritize expanding wetland water body areas,enhancing wetland connectivity,minimizing human disturbance during the breeding season,and implementing ecological restoration measures in urbanized wetlands to mitigate adverse effects of urbanization.展开更多
WATER technology,urban management,low-carbon transformation,digital and intelligent development–these were the keywords in the Exhibition Hall of Environmental Services at Shougang Park,a former steel plant that has ...WATER technology,urban management,low-carbon transformation,digital and intelligent development–these were the keywords in the Exhibition Hall of Environmental Services at Shougang Park,a former steel plant that has been transformed into a vibrant new cultural landmark of Beijing,during the 2025 China International Fair for Trade in Services(CIFTIS)held from September 10 to 14,2025.展开更多
文摘Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field.
文摘In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-quality urban development and continuously meet people’s growing aspirations for a better life.Wuhu,in central China’s Anhui Province,has consistently enhanced its urban functions and services to build a modern,people-oriented city that is innovative,livable,beautiful,resilient,and smart.
基金The National Key Research and Development Project,No.2022YFF1303204。
文摘Enhancing urban ecological resilience(UER)is a new concept for modern tourism-oriented cities to cope with environmental crises.Revealing the impact of the urbanization on UER is critical to the sustainability of urban ecosystems.Taking Zhangjiajie,a typical tourism-oriented city,as an example,urbanization level(UL)and UER evaluation system were constructed,and the change trend was analyzed.The Granger Causality Test model was used to discuss the relationship between UL and UER.The results showed that:(1)the urbanization rate of Zhangjiajie significantly increased by 0.531 from 2011 to 2020.Cili county has the highest UL,and Wulingyuan district including a large number of scenic spots has the fastest development trend.(2)The ecological restoration was more sensitive in the face of rising pressure,and showed a synchronized change trend with pressure.The high pressure in 2016 had the most significant impact on resistance.This effect continued into 2019,with an average decline in resistance of 0.802.(3)The UL has significantly promoted the improvement of urban ecological restoration.Specially,tourism urbanization was the most significant in scenic spots,while economic and social urbanization played a major role in other regions for the improvement of ecological restoration.
文摘China is carving out a distinctive development path which features urban-rural integration.This approach has not only yielded tangible results domestically but also drawn the attention of other countries.
文摘The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack of sanitation facilities.The project,targeting 14,082 households,started last year.
基金supported by the Japan Society for the Promotion of Science(JSPS)Grants-in-Aid for Scientific Research(C)23K03898.
文摘Traffic at urban intersections frequently encounters unexpected obstructions,resulting in congestion due to uncooperative and priority-based driving behavior.This paper presents an optimal right-turn coordination system for Connected and Automated Vehicles(CAVs)at single-lane intersections,particularly in the context of left-hand side driving on roads.The goal is to facilitate smooth right turns for certain vehicles without creating bottlenecks.We consider that all approaching vehicles share relevant information through vehicular communications.The Intersection Coordination Unit(ICU)processes this information and communicates the optimal crossing or turning times to the vehicles.The primary objective of this coordination is to minimize overall traffic delays,which also helps improve the fuel consumption of vehicles.By considering information from upcoming vehicles at the intersection,the coordination system solves an optimization problem to determine the best timing for executing right turns,ultimately minimizing the total delay for all vehicles.The proposed coordination system is evaluated at a typical urban intersection,and its performance is compared to traditional traffic systems.Numerical simulation results indicate that the proposed coordination system significantly enhances the average traffic speed and fuel consumption compared to the traditional traffic system in various scenarios.
基金supported by the Science and Technology Project of Sichuan Electric Power Company“Power Supply Guarantee Strategy for Urban Distribution Networks Considering Coordination with Virtual Power Plant during Extreme Weather Event”(No.521920230003).
文摘Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study.
基金The researchers would like to thank the Deanship of Graduate Studies and Scientific Research at Qassim University for financial support(QU-APC-2025)。
文摘The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often advanced one dimension—such as Internet of Things(IoT)-based data acquisition,Artificial Intelligence(AI)-driven analytics,or digital twin visualization—without fully integrating these strands into a single operational loop.As a result,many existing solutions encounter bottlenecks in responsiveness,interoperability,and scalability,while also leaving concerns about data privacy unresolved.This research introduces a hybrid AI–IoT–Digital Twin framework that combines continuous sensing,distributed intelligence,and simulation-based decision support.The design incorporates multi-source sensor data,lightweight edge inference through Convolutional Neural Networks(CNN)and Long ShortTerm Memory(LSTM)models,and federated learning enhanced with secure aggregation and differential privacy to maintain confidentiality.A digital twin layer extends these capabilities by simulating city assets such as traffic flows and water networks,generating what-if scenarios,and issuing actionable control signals.Complementary modules,including model compression and synchronization protocols,are embedded to ensure reliability in bandwidth-constrained and heterogeneous urban environments.The framework is validated in two urban domains:traffic management,where it adapts signal cycles based on real-time congestion patterns,and pipeline monitoring,where it anticipates leaks through pressure and vibration data.Experimental results show a 28%reduction in response time,a 35%decrease in maintenance costs,and a marked reduction in false positives relative to conventional baselines.The architecture also demonstrates stability across 50+edge devices under federated training and resilience to uneven node participation.The proposed system provides a scalable and privacy-aware foundation for predictive urban infrastructure management.By closing the loop between sensing,learning,and control,it reduces operator dependence,enhances resource efficiency,and supports transparent governance models for emerging smart cities.
基金supported by the National Natural Science Foun-dation of China(Grants No.42330103,42271469)the Ningbo Science and Technology Bureau(Grant No.2022Z081).
文摘The gap between the projected urban areas in the current trend(UAC)and those in the sustainable scenario(UAS)is a critical factor in understanding whether cities can fulfill the requirements of sustainable development.However,there is a paucity of knowledge on this cutting-edge topic.Given the extensive and rapid urbanization in the United States(U.S.)over the past two centuries,accurately measuring this gap between UAS and UAC is of critical importance for advancing future sustainable urban development,as well as having significant global implications.This study finds that although the 740 U.S.cities have a large UAC in 2100,these cities will encom pass a significant gap from UAC to UAS(approximately 165,000 km2),accounting for 30%UAC at that time.The study also reveals the spatio-temporal heterogeneity of the gap.The gap initially increases before reaching a inflection point in 2090,and it disparates greatly from−100%to 240%at city level.While cities in the Northwestern U.S.maintain UAC that exceeds UAS from 2020 to 2100,cities in other regions shift from UAC that exceeds UAS to UAC that falls short of UAS.Filling the gap without additional urban growth planning could lead to a reduction of crop production ranging from 0.3%to 3%and a 0.68%loss of biomass.Hence,dynamic and forward-looking urban planning is essential for addressing the challenges of sustainable development posed by urbanization,both within the U.S.and globally.
基金sponsored by the U.S.Department of Housing and Urban Development(Grant No.NJLTS0027-22)The opinions expressed in this study are the authors alone,and do not represent the U.S.Depart-ment of HUD’s opinions.
文摘This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models offer insights, they fall short in presenting a holistic view of complex urban challenges. System dynamics (SD) models that are often utilized to provide holistic, systematic understanding of a research subject, like the urban system, emerge as valuable tools, but data scarcity and theoretical inadequacy pose challenges. The research reviews relevant papers on recent SD model applications in urban sustainability since 2018, categorizing them based on nine key indicators. Among the reviewed papers, data limitations and model assumptions were identified as ma jor challenges in applying SD models to urban sustainability. This led to exploring the transformative potential of big data analytics, a rare approach in this field as identified by this study, to enhance SD models’ empirical foundation. Integrating big data could provide data-driven calibration, potentially improving predictive accuracy and reducing reliance on simplified assumptions. The paper concludes by advocating for new approaches that reduce assumptions and promote real-time applicable models, contributing to a comprehensive understanding of urban sustainability through the synergy of big data and SD models.
基金National Natural Science Foundation of China,No.42330106。
文摘Dryland regions face complex interactions between urbanization and ecological changes,where effective coordination is essential for enhancing sustainability and resilience.However,most studies concentrate on the national or provincial scales,with insufficient research on county-level coordination,limiting the ability to provide targeted polifrom a precise perspective.This study addresses this gap by analyzing 39 counties within the Hohhot-Baotou-Ordos-Yulin Urban Agglomeration(HBOYUA),a typical dryland urban cluster in China.We use daytime and nighttime remote sensing images to track the spatio-temporal evolution of urbanization and ecological conditions from 1992 to 2023.A novel quantitative framework based on an improved coupling coordination degree(CCD)is proposed to assess their coordination relationship.The results reveal that:(1)Urbanization and ecological quality both exhibited fluctuating upward trends,with spatial heterogeneity increasing for urbanization and decreasing for the eco-environment.Regions with better ecological conditions had higher urbanization levels.(2)The overall coordinated level improved from imbalance(0.36)to low-level coordination(0.55),although its spatial distribution remained uneven,with central urban areas showing higher CCD than surrounding counties.(3)Socioeconomic factors exerted greater effects on CCD than natural factors,with GDP and land surface temperature(LST)playing a significant role in interaction analysis.(4)In western arid regions,urbanization did not necessarily harm ecosystems;instead,ecological conditions improved alongside urbanization.This research offers targeted and valuable references for county and city governments in resource allocation and sustainable development.The proposed methodology is also adaptable for urban resilience studies in other regions.
基金funded by the Directorate of Research and Community Service, Ministry of Education, Culture, Research, and Technology, Indonesia (027/E5/PG.02.00.PL/2024)Bogor Agricultural University for their invaluable support and resources that made this research possibleDirectorate of Research and Community Service, Ministry of Education, Culture, Research, and Technology, Indonesia, for their financial and administrative support
文摘Urbanization in small-and medium-sized cities has often been overlooked in urban studies.Research on urbanization has predominantly focused on large metropolitan cities;however,urbanization in small-and medium-sized cities also contributes to the acceleration of urban sprawl.Urban growth boundary(UGB)is an ecological approach designed to limit urban development.This study aimedto analyze environmental protection priority zonesby combining ecological quality and sensitivity indices to identify the areas suitable for UGB implementation.Tegal City and its surrounding areas(including Tegal and Brebes regencies)of Indonesia were selected as the study area.The ecological quality index was calculated using the normalized difference vegetation index,humidity index,land surface temperature,and normalized difference bare soil index.These indices were subsequently subjected to principal component analysis(PCA)to extract orthogonal factors,which were summed to derive the final index value.In parallel,we mapped and evaluated ecological sensitivity based on spatial planning policies and regulations.The results revealed that ecological quality in Tegal and Brebes regencies was predominantly categorized as good and very good ecological quality,whereas TegalCity exhibited moderate and poor ecological quality.Additionally,over 45.00%of the area in Tegal and Brebes regencies demonstrated very high ecological sensitivity.Consequently,more than 50.00%of the area in Tegal and Brebes regencies,along with 27.00%of Tegal City,were classified as ecological constraint zone,making them potential regionsfor UGB development.The UGB is expected to curtail urban expansion,promote compact city planning,and preserve ecosystem services to achieve urban sustainability.This study implies that planningsmall-and medium-sized cities is important to prevent urban sprawl and maintain environmental health.Designing UGB to limit urban expansion should be enhanced by better knowledge about its ecological functions in supporting urban sustainability.
文摘Urban memory is the soul and vitality of the city, which is created and maintained by people’s memory of the living environment. However, urban planning and architecture increasingly lose attention to urban memory, resulting in the loss of uniqueness of urban appearance, and then affect people’s sense of identity of the city. Therefore, using the theory of typology for reference, a new design tool - urban memory typology is proposed, which focuses on and introduces historical elements into urban design, and maintains urban memory through the protection of cultural heritage. This method involves clarifying the intrinsic relationship between existing buildings and urban space through typology theory, identifying carriers of urban memory, and, on this basis, proposing strategies and technologies for urban renewal. This study verifies the validity of urban memory typology through case analysis, such as the conservation planning of Qingdao Old city. The results show that using the typology theory can protect the city memory, maintain the stability of the city form, and enhance the local identity of the residents, which is a new method of urban planning and design in line with the concept of humanistic care and sustainable development. This research work provides new theoretical guidance and practical strategies for the protection of urban memory and urban planning and design.
基金Under the auspices of Liaoning Revitalization Talents Program(No.XLYC2202024)Basic Scientific Research Project(Key Project)of the Education Department of Liaoning Province(No.LJ212410165084)the Fundamental Research Funds for the Central Universities(No.N2111003,N2411001)。
文摘To adapt to national climate change strategies,understanding the thermal vulnerability of urban functional zones(UFZs)is critical for enhancing the livability and sustainable development of cities.We address the limitations of existing thermal vulnerability assessments by incorporating human perception into the analysis.Specifically,we introduce the sky openness index to reflect human perception of the thermal environment and examine variations in thermal vulnerability across different UFZs.Using the Extreme Gradient Boosting(XGBoost)-SHapley Additive exPlanations(SHAP)model,we analyze the contributions of 2D and 3D urban form indicators to thermal vulnerability and link these contributions to the unique needs and vulnerability characteristics of UFZs of Foshan City,China in 2023.The results reveal that:1)high-value heat-fragile areas(1.74–2.00]constitute 10.42%of Foshan City;2)traffic zone and publiccommercial zone exhibit the highest levels of thermal vulnerability;and 3)building height and the normalized building index are the most influential factors,with contributions of|0.06|and|0.03|,respectively.We provide a scientific foundation for developing governance strategies to promote urban resilience.
基金supported by the Key Program of the National Natural Science Foundation of China(Grant No.41931293)the National Natural Science Foundation of China(Grant No.42271275).
文摘The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to investigate the impacts of urbanization on ESV in China.However,a comprehensive and dynamic framework to reveal the relationship between ESV and urbanization processes is lacking.This study adopted multi-source datasets to portray China’s urbanization process by integrating population,land,and economic urbanization,eval-uated the ESV changes of 10 categories by gross ecosystem product(GEP)methods,and explored ESV changes within different urbanization scales and speeds.The results showed rapid urbanization in the population,land,and economic dimensions in China,with a faster process of economic urbanization.The ESV also exhibited an increasing trend,with higher levels in the southeastern coastal regions and lower levels in the northwestern regions.Urbanization had positive impacts on ESV across various research units,but the ESV exhibited heteroge-neous changes across different urbanization scales,speeds,and their interactive effects.The response of ESV to dynamic urbanization processes was influenced by socio-economic,ecological,and policy factors;it is essential to combine targeted measures with general ecological product value realization methods in each unit to maximize social-economic-ecological benefits.
基金National Natural Science Foundation of China,No.42171455The Hong Kong RGC Research Impact Fund,No.R5011-23The Hong Kong General Research Fund,No.15204121。
文摘Urban environments offer a wealth of opportunities for residents to respite from their hectic life.Outdoor running or jogging becomes increasingly popular of an option.Impacts of urban environments on outdoor running,despite some initial studies,remain underexplored.This study aims to establish an analytical framework that can holistically assess the urban environment on the healthy vitality of running.The proposed framework is applied to two modern Chinese cities,i.e.,Guangzhou and Shenzhen.We construct three interpretable random forest models to explore the non-linear relationship between environmental variables and running intensity(RI)through analyzing the runners'trajectories and integrating with multi-source urban big data(e.g.,street view imagery,remote sensing,and socio-economic data)across the built,natural,and social dimensions,The findings uncover that road density has the greatest impact on RI,and social variables(e.g.,population density and housing price)and natural variables(e.g.,slope and humidity)all make notable impact on outdoor running.Despite these findings,the impact of environmental variables likely change across different regions due to disparate regional construction and micro-environments,and those specific impacts as well as optimal thresholds also alter.Therefore,construction of healthy cities should take the whole urban environment into account and adapt to local conditions.This study provides a comprehensive evaluation on the influencing variables of healthy vitality and guides sustainable urban planning for creating running-friendly cities.
基金supported by the National Key R&D Program of China(No.2023YFC3805100)the National Natural Science Foundation of China(Nos.52222811 and 52494963)。
文摘Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept of urban seismic resilience(USR),its assessment is a large-scale system engineering issue.The assessment of USR should be based on the notion of urban seismic capacity(USC)assessment,which includes casualties,economic loss,and recovery time as criteria.Functionality loss is also included in the assessment of USR in addition to these criteria.The assessment indicator system comprising five dimensions(building and lifeline infrastructure,environment,society,economy,and institution)and 20 indicators has been devised to quantify USR.The analytical hierarchy process(AHP)is utilized to compute the weights of the criteria,dimensions,and indicators in the urban seismic resilience assessment(USRA)indicator system.When the necessary data for a city are obtainable,the seismic resilience of that city can be assessed using this framework.To illustrate the proposed methodology,a moderate-sized city in China was selected as a case study.The assessment results indicate a high level of USR,suggesting that the city possesses strong capabilities to withstand and recover from potential future earthquakes.
基金supported by the National Natural Science Foundation of China(No.32271734)。
文摘The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system.
基金supported by the National Natural Science Foundation of China(32271743).
文摘Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their diversity in urban wetlands reflects the response of wildlife to urbanization.However,very few studies have investigated seasonal differences in the multidimensional diversity of waterbirds in urbanized landscapes.In this study,we analyzed various wetland parameters that could potentially affect the seasonal variations in multidimensional diversity of waterbirds in Nanjing,China.We surveyed waterbirds in 29 urban wetlands using the point count method during breeding and non-breeding seasons from November 2022 to June 2023.We then employed multiple linear regressions and information-theoretic approaches to investigate the impact of wetland characteristics on waterbird diversity.We found that water body area and buffer zone connectivity consistently emerged as positive factors affecting waterbird taxonomic and phylogenetic diversity across seasons.Conversely,the urbanization synthetic index was negatively correlated with waterbird diversity only during the breeding season.Regarding functional diversity,we found that the positive correlation between buffer zone connectivity and waterbird diversity was specific to the breeding season.Therefore,for effective conservation of waterbird diversity in our system,wetland planning should prioritize expanding wetland water body areas,enhancing wetland connectivity,minimizing human disturbance during the breeding season,and implementing ecological restoration measures in urbanized wetlands to mitigate adverse effects of urbanization.
文摘WATER technology,urban management,low-carbon transformation,digital and intelligent development–these were the keywords in the Exhibition Hall of Environmental Services at Shougang Park,a former steel plant that has been transformed into a vibrant new cultural landmark of Beijing,during the 2025 China International Fair for Trade in Services(CIFTIS)held from September 10 to 14,2025.
