Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street...Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street in Haikou,the capital of Hainan Province,served as the embarkation point for Hainanese setting out on their maritime voyages to seek greener pastures.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
This research was carried out to identify the most effective plant species for air purification based on environmental factors. The existence of plants beside roadways can be considered a more efficient approach to im...This research was carried out to identify the most effective plant species for air purification based on environmental factors. The existence of plants beside roadways can be considered a more efficient approach to improving air quality and minimizing pollution exposure. The samples for this research were collected from various sites across the streets of Jeddah governorate. The primary sources of air pollution in the research area are vehicle traffic and emissions from cars. Eight species were gathered from various streets in Jeddah governorate, namely, Azadirachta indica, Senna sulfurea, Ziziphus spina-christi, Cordia sebestena, Tecoma stans, Bougainvillea spectabilis, Conocarpus lancifolius, and Ixora coccinea. The leaves of the studied plants were analyzed for secondary compounds using Gas chromatography-mass spectrometry (GC-MS) techniques. Gas-chromatographic analyses revealed that bis (2-ethylhexyl) phthalate was found in every plant. Bis-(2-ethylhexyl) phthalate, a widespread environmental pollutant. Moreover, Cordia sebestena was the sole plant that contained Phenol, 2,2’-methylenebis [6-(1,1-dimethylethyl)-4-methyl] which is part of the phenols category. Environmental conditions can affect the production of secondary metabolites. By tracking the concentrations of these substances, researchers can evaluate the well-being of ecosystems and identify pollution.展开更多
This article focuses on the planning and design of the Haikou Qilou Old Street,a distinctive cultural street landscape,in the context of a free trade port.By thoroughly analyzing the historical and cultural value of t...This article focuses on the planning and design of the Haikou Qilou Old Street,a distinctive cultural street landscape,in the context of a free trade port.By thoroughly analyzing the historical and cultural value of the Qilou Old Street and its current issues,and considering the opportunities and challenges presented by the free trade port development,the article proposes targeted planning and design strategies in areas such as functional layout,traffic organization,cultural heritage and innovation,and landscape element design.The aim is to create a unique and high-quality cultural street landscape that serves as a shining card for Haikou’s urban culture,promoting the coordinated development of regional economy and culture,and providing a reference for the renewal and development of similar historical and cultural districts.展开更多
A stroll through Nanluoguxiang漫步南锣鼓巷Last autumn,I wandered into Nanluoguxiang on a sunny morning.The narrow alley,paved with gray flagstones,twisted like a quiet snake between old courtyard houses.A granny sat o...A stroll through Nanluoguxiang漫步南锣鼓巷Last autumn,I wandered into Nanluoguxiang on a sunny morning.The narrow alley,paved with gray flagstones,twisted like a quiet snake between old courtyard houses.A granny sat on a bamboo chair outside her door,sorting beans,and smiled as I passed.“This lane's been here for 800 years,”she said,pointing to the worn stone threshold.She offered me a handful of candied hawthorns,their sweetness mixing with the earthy smell of hutong.展开更多
Currently,most conventional street lighting systems use a constant light mode throughout the entire night,fromsunset to sunrise,which results in high energy consumption and maintenance costs.Furthermore,scientific res...Currently,most conventional street lighting systems use a constant light mode throughout the entire night,fromsunset to sunrise,which results in high energy consumption and maintenance costs.Furthermore,scientific research predicts that energy consumption for street lighting will increase in the coming years due to growing demand and rising electricity prices.The dimming strategy is a current trend and a key concept in smart street lighting systems.It involves turning on the road lights only when a vehicle or pedestrian is detected;otherwise,the control system reduces the light intensity of the lamps.Power control is generally implemented using artificial intelligence algorithms such as fuzzy logic,artificial neural networks,or swarm intelligence to manage different events.In our project,the dimming strategy was utilized to reduce costs and energy consumption by at least 48%.This research proposes a standalone photovoltaic plant(SPP)to power a smart street lighting system,which can replace individual solar street lights in a small neighborhood in southwestern Algeria.This design offers advantages such as lower costs and the option to add additional loads a DC pump,a domestic power supply,or technical services to operate the photovoltaic system during the day after charging the storage batteries,especially when there is monthly energy surplus.The energy surplus analyzed in our project ranges from 804 W in January to 4 kW in June,generated by the entire PV installation.To demonstrate the feasibility and reliability of this system,we studied the implementation of the standalone photovoltaic plant,energymanagement,and economic analysis using the Particle SwarmOptimization technique under MATLAB software.展开更多
Materials used in building envelopes and urban areas contribute significantly to the urban heat island(UHI).In this context,this paper presents a study utilizing infrared thermography(IRT)to assess urban streets and b...Materials used in building envelopes and urban areas contribute significantly to the urban heat island(UHI).In this context,this paper presents a study utilizing infrared thermography(IRT)to assess urban streets and building surface materials in the coastal city of Bayahibe,Dominican Republic.Measurements were conducted in situ in six urban street canyons(Sections A–F)during the warmest and coldest weather conditions.A FLIR T420 thermal camera,FLIR Tools+software,and the emissivity values of common building materials in Bayahibe were used to determine surface temperatures under sunlit and shaded conditions.The findings show that sunlit surfaces of urban elements generally exhibited higher surface temperatures compared to their shaded counterparts in both warm and cold periods.Metal surfaces displayed the most significant surface temperature differences between sunlit and shaded areas.Additionally,light-colored block walls presented lower surface temperatures than medium and dark-colored ones.This research provides insights into the urban microclimate of Bayahibe under different meteorological conditions.It supports the development of strategies to mitigate the UHI effect and enhance pedestrian thermal comfort in tropical and coastal cities by emphasizing the importance of shading elements and light-colored surfaces.The findings can inform specific interventions and policies for creating more sustainable and climate-resilient urban environments in the Caribbean region.展开更多
Kármán vortex street not only exists in nature,but also widely appears in engineering practice,which is of great significance for understanding superfluid.Parity-time(PT)symmetric potential provides a good p...Kármán vortex street not only exists in nature,but also widely appears in engineering practice,which is of great significance for understanding superfluid.Parity-time(PT)symmetric potential provides a good platform for the study of Kármán vortex streets.In this paper,different patterns of vortex shedding formed behind PT symmetric potential in Bose-Einstein condensate(BEC)are simulated numerically.Kármán vortex streets and others are discovered to emerge in the wake of a moving obstacle with appropriate parameters.Compared with BEC without PT symmetric potential,the frequency and amplitude of the drag force are more complex.The parametric regions of the combined modes are scattered around the Kármán vortex street.Numerical simulations indicate that the imaginary part of the PT symmetric potential affects the vortex structure patterns.Finally,we proposed an experimental protocol that may observe a Kármán vortex street.展开更多
Semantic segmentation in street scenes is a crucial technology for autonomous driving to analyze the surrounding environment.In street scenes,issues such as high image resolution caused by a large viewpoints and diffe...Semantic segmentation in street scenes is a crucial technology for autonomous driving to analyze the surrounding environment.In street scenes,issues such as high image resolution caused by a large viewpoints and differences in object scales lead to a decline in real-time performance and difficulties in multi-scale feature extraction.To address this,we propose a bilateral-branch real-time semantic segmentationmethod based on semantic information distillation(BSDNet)for street scene images.The BSDNet consists of a Feature Conversion Convolutional Block(FCB),a Semantic Information Distillation Module(SIDM),and a Deep Aggregation Atrous Convolution Pyramid Pooling(DASP).FCB reduces the semantic gap between the backbone and the semantic branch.SIDM extracts high-quality semantic information fromthe Transformer branch to reduce computational costs.DASP aggregates information lost in atrous convolutions,effectively capturingmulti-scale objects.Extensive experiments conducted on Cityscapes,CamVid,and ADE20K,achieving an accuracy of 81.7% Mean Intersection over Union(mIoU)at 70.6 Frames Per Second(FPS)on Cityscapes,demonstrate that our method achieves a better balance between accuracy and inference speed.展开更多
Through the investigation of the species of street trees located along the main urban roads in Hefei City,a total of 22 species were selected,belonging to 16 families and 22 genera,with the Sapindaceae family being th...Through the investigation of the species of street trees located along the main urban roads in Hefei City,a total of 22 species were selected,belonging to 16 families and 22 genera,with the Sapindaceae family being the most prevalent.In this study,the Analytic Hierarchy Process(AHP)was employed to assess the comprehensive value of 22 species of street trees applied along the main urban roads in Hefei City.Fourteen evaluation criteria were selected from four categories:morphological indices,functional indices,resistance indices,and management indices,to develop a comprehensive evaluation model.Based on a composite score derived from 22 street trees,these trees were classified into three distinct grades.Grade I(L≥3.0)exhibited a high comprehensive application value in Hefei City and included 6 tree species,such asPlatanus.Grade II(2.5≤L<3.0)also demonstrated a high comprehensive application value,comprising 15 tree species,includingCatalpabungei.In contrast,grade III(L<2.5)indicated a general comprehensive application value,represented by a single species,Cedrusdeodara.The evaluation results can offer theoretical insights for the selection of urban street trees.展开更多
High-rise buildings form deep urban street canyons and restrict the dispersion of vehicle emissions,posing severe health risks to the public by aggravating roadside air quality.Field measurements are important for und...High-rise buildings form deep urban street canyons and restrict the dispersion of vehicle emissions,posing severe health risks to the public by aggravating roadside air quality.Field measurements are important for understanding the dispersion process of tailpipe emissions in street canyons,while a major challenge is the lack of a suitable tracer gas.Carbon dioxide(CO_(2)),which is safe to the public and inexpensive to obtain,can be reliably measured by existing gas analysers.This study investigated the suitability of using CO_(2)as a tracer gas for characterising vehicle emission dispersion in a real-world street canyon.The tracer gas was released via a line or point source,whose dispersion was characterised by a sensors network comprising low-cost air quality sensors.The results showed that the CO_(2)contained in the exhaust gas of a test vehicle itself had unmeasurable effect at roadsides.Both the line and point sources produced obvious CO_(2)level elevations at approximately 30 s after the test vehicle passed by.In addition,for both line and point sources,the CO_(2)elevations were much more distinct at the roadside next to tailpipe exit than the opposite side,and were higher at 0.8 m than 1.6 m above the ground.The present study demonstrated that using CO_(2)as a tracer gas is feasible for investigating vehicle emission dispersion in real-world street canyons.Future studies are needed to improve the gas release rate of the developed tracer gas systems for more reliable measurements and larger street canyons.展开更多
文摘Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street in Haikou,the capital of Hainan Province,served as the embarkation point for Hainanese setting out on their maritime voyages to seek greener pastures.
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.
文摘This research was carried out to identify the most effective plant species for air purification based on environmental factors. The existence of plants beside roadways can be considered a more efficient approach to improving air quality and minimizing pollution exposure. The samples for this research were collected from various sites across the streets of Jeddah governorate. The primary sources of air pollution in the research area are vehicle traffic and emissions from cars. Eight species were gathered from various streets in Jeddah governorate, namely, Azadirachta indica, Senna sulfurea, Ziziphus spina-christi, Cordia sebestena, Tecoma stans, Bougainvillea spectabilis, Conocarpus lancifolius, and Ixora coccinea. The leaves of the studied plants were analyzed for secondary compounds using Gas chromatography-mass spectrometry (GC-MS) techniques. Gas-chromatographic analyses revealed that bis (2-ethylhexyl) phthalate was found in every plant. Bis-(2-ethylhexyl) phthalate, a widespread environmental pollutant. Moreover, Cordia sebestena was the sole plant that contained Phenol, 2,2’-methylenebis [6-(1,1-dimethylethyl)-4-methyl] which is part of the phenols category. Environmental conditions can affect the production of secondary metabolites. By tracking the concentrations of these substances, researchers can evaluate the well-being of ecosystems and identify pollution.
基金Research Project of Hainan Vocational University of Science and Technology in 2024“Research on the Planning and Design of Characteristic Cultural Street Landscape of Haikou Qilou Old Street under the Background of Free Trade Port”(Project No.:HKKY2024-45)。
文摘This article focuses on the planning and design of the Haikou Qilou Old Street,a distinctive cultural street landscape,in the context of a free trade port.By thoroughly analyzing the historical and cultural value of the Qilou Old Street and its current issues,and considering the opportunities and challenges presented by the free trade port development,the article proposes targeted planning and design strategies in areas such as functional layout,traffic organization,cultural heritage and innovation,and landscape element design.The aim is to create a unique and high-quality cultural street landscape that serves as a shining card for Haikou’s urban culture,promoting the coordinated development of regional economy and culture,and providing a reference for the renewal and development of similar historical and cultural districts.
文摘A stroll through Nanluoguxiang漫步南锣鼓巷Last autumn,I wandered into Nanluoguxiang on a sunny morning.The narrow alley,paved with gray flagstones,twisted like a quiet snake between old courtyard houses.A granny sat on a bamboo chair outside her door,sorting beans,and smiled as I passed.“This lane's been here for 800 years,”she said,pointing to the worn stone threshold.She offered me a handful of candied hawthorns,their sweetness mixing with the earthy smell of hutong.
文摘Currently,most conventional street lighting systems use a constant light mode throughout the entire night,fromsunset to sunrise,which results in high energy consumption and maintenance costs.Furthermore,scientific research predicts that energy consumption for street lighting will increase in the coming years due to growing demand and rising electricity prices.The dimming strategy is a current trend and a key concept in smart street lighting systems.It involves turning on the road lights only when a vehicle or pedestrian is detected;otherwise,the control system reduces the light intensity of the lamps.Power control is generally implemented using artificial intelligence algorithms such as fuzzy logic,artificial neural networks,or swarm intelligence to manage different events.In our project,the dimming strategy was utilized to reduce costs and energy consumption by at least 48%.This research proposes a standalone photovoltaic plant(SPP)to power a smart street lighting system,which can replace individual solar street lights in a small neighborhood in southwestern Algeria.This design offers advantages such as lower costs and the option to add additional loads a DC pump,a domestic power supply,or technical services to operate the photovoltaic system during the day after charging the storage batteries,especially when there is monthly energy surplus.The energy surplus analyzed in our project ranges from 804 W in January to 4 kW in June,generated by the entire PV installation.To demonstrate the feasibility and reliability of this system,we studied the implementation of the standalone photovoltaic plant,energymanagement,and economic analysis using the Particle SwarmOptimization technique under MATLAB software.
基金funding by project“Use of Digital Information Technologies for Adaptation of the Effects of Climate Change in Touristic Coastal Zones of the Dominican Republic”(ADAPT_CCDR),grant number FED/2020/420-874funded by Harnessing Innovative Technologies to support Resilient Settlements on the Coastal Zones of the Caribbean(HIT RESET CARIBBEAN CARIBBEAN)implement by The University of the West Indies(The UWI),Anton de Kom University of Suriname(AdeKUS)and Caribbean Disaster and Emergency Management Agency(CDEMA),sponsored by the ACP-EU Innovation Fund,implemented by the Organization of African,Caribbean and Pacific States(OACPS)Research and Innovation Program,with the financial assistance of the European Union.
文摘Materials used in building envelopes and urban areas contribute significantly to the urban heat island(UHI).In this context,this paper presents a study utilizing infrared thermography(IRT)to assess urban streets and building surface materials in the coastal city of Bayahibe,Dominican Republic.Measurements were conducted in situ in six urban street canyons(Sections A–F)during the warmest and coldest weather conditions.A FLIR T420 thermal camera,FLIR Tools+software,and the emissivity values of common building materials in Bayahibe were used to determine surface temperatures under sunlit and shaded conditions.The findings show that sunlit surfaces of urban elements generally exhibited higher surface temperatures compared to their shaded counterparts in both warm and cold periods.Metal surfaces displayed the most significant surface temperature differences between sunlit and shaded areas.Additionally,light-colored block walls presented lower surface temperatures than medium and dark-colored ones.This research provides insights into the urban microclimate of Bayahibe under different meteorological conditions.It supports the development of strategies to mitigate the UHI effect and enhance pedestrian thermal comfort in tropical and coastal cities by emphasizing the importance of shading elements and light-colored surfaces.The findings can inform specific interventions and policies for creating more sustainable and climate-resilient urban environments in the Caribbean region.
基金supported by the National Natural Science Foundation of China under Grant Nos.12065022,12147213。
文摘Kármán vortex street not only exists in nature,but also widely appears in engineering practice,which is of great significance for understanding superfluid.Parity-time(PT)symmetric potential provides a good platform for the study of Kármán vortex streets.In this paper,different patterns of vortex shedding formed behind PT symmetric potential in Bose-Einstein condensate(BEC)are simulated numerically.Kármán vortex streets and others are discovered to emerge in the wake of a moving obstacle with appropriate parameters.Compared with BEC without PT symmetric potential,the frequency and amplitude of the drag force are more complex.The parametric regions of the combined modes are scattered around the Kármán vortex street.Numerical simulations indicate that the imaginary part of the PT symmetric potential affects the vortex structure patterns.Finally,we proposed an experimental protocol that may observe a Kármán vortex street.
基金supported in part by the National Natural Science Foundation of China[Grant number 62471075]the Major Science and Technology Project Grant of the Chongqing Municipal Education Commission[Grant number KJZD-M202301901]Graduate Innovation Fund of Chongqing[gzlcx20253235].
文摘Semantic segmentation in street scenes is a crucial technology for autonomous driving to analyze the surrounding environment.In street scenes,issues such as high image resolution caused by a large viewpoints and differences in object scales lead to a decline in real-time performance and difficulties in multi-scale feature extraction.To address this,we propose a bilateral-branch real-time semantic segmentationmethod based on semantic information distillation(BSDNet)for street scene images.The BSDNet consists of a Feature Conversion Convolutional Block(FCB),a Semantic Information Distillation Module(SIDM),and a Deep Aggregation Atrous Convolution Pyramid Pooling(DASP).FCB reduces the semantic gap between the backbone and the semantic branch.SIDM extracts high-quality semantic information fromthe Transformer branch to reduce computational costs.DASP aggregates information lost in atrous convolutions,effectively capturingmulti-scale objects.Extensive experiments conducted on Cityscapes,CamVid,and ADE20K,achieving an accuracy of 81.7% Mean Intersection over Union(mIoU)at 70.6 Frames Per Second(FPS)on Cityscapes,demonstrate that our method achieves a better balance between accuracy and inference speed.
基金Sponsored by Provincial-level Undergraduate Innovation Training Program of Anhui Xinhua University(S202312216043)Natural Science Key Research Program for Colleges and Universities in Anhui Province(2023AH051816)Anhui General Teaching Research Project(2022jyxm665).
文摘Through the investigation of the species of street trees located along the main urban roads in Hefei City,a total of 22 species were selected,belonging to 16 families and 22 genera,with the Sapindaceae family being the most prevalent.In this study,the Analytic Hierarchy Process(AHP)was employed to assess the comprehensive value of 22 species of street trees applied along the main urban roads in Hefei City.Fourteen evaluation criteria were selected from four categories:morphological indices,functional indices,resistance indices,and management indices,to develop a comprehensive evaluation model.Based on a composite score derived from 22 street trees,these trees were classified into three distinct grades.Grade I(L≥3.0)exhibited a high comprehensive application value in Hefei City and included 6 tree species,such asPlatanus.Grade II(2.5≤L<3.0)also demonstrated a high comprehensive application value,comprising 15 tree species,includingCatalpabungei.In contrast,grade III(L<2.5)indicated a general comprehensive application value,represented by a single species,Cedrusdeodara.The evaluation results can offer theoretical insights for the selection of urban street trees.
基金supported by the Environment and Conservation Fund(No.ECF 14/2018)of the Hong Kong SAR Government,China.
文摘High-rise buildings form deep urban street canyons and restrict the dispersion of vehicle emissions,posing severe health risks to the public by aggravating roadside air quality.Field measurements are important for understanding the dispersion process of tailpipe emissions in street canyons,while a major challenge is the lack of a suitable tracer gas.Carbon dioxide(CO_(2)),which is safe to the public and inexpensive to obtain,can be reliably measured by existing gas analysers.This study investigated the suitability of using CO_(2)as a tracer gas for characterising vehicle emission dispersion in a real-world street canyon.The tracer gas was released via a line or point source,whose dispersion was characterised by a sensors network comprising low-cost air quality sensors.The results showed that the CO_(2)contained in the exhaust gas of a test vehicle itself had unmeasurable effect at roadsides.Both the line and point sources produced obvious CO_(2)level elevations at approximately 30 s after the test vehicle passed by.In addition,for both line and point sources,the CO_(2)elevations were much more distinct at the roadside next to tailpipe exit than the opposite side,and were higher at 0.8 m than 1.6 m above the ground.The present study demonstrated that using CO_(2)as a tracer gas is feasible for investigating vehicle emission dispersion in real-world street canyons.Future studies are needed to improve the gas release rate of the developed tracer gas systems for more reliable measurements and larger street canyons.
