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
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
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
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
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
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
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
The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent year...The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent years,with the technological and economic development,smart street lighting has gradually emerged.Key functions of smart street lighting include road illumination,cultural promotion,meteorological monitoring,public broadcasting,and 5G micro-base stations.The overall quality of smart street lighting construction directly impacts the effectiveness of urban development and the city’s comprehensive growth.This paper analyzes the concept of smart street lighting,its advantages and disadvantages,the functionalities of smart street light systems,and the application of smart street lighting in urban road illumination.展开更多
The dynamics of spin–orbit-coupled Bose–Einstein condensate with parity-time symmetry through a moving obstacle potential is simulated numerically. In the miscible two-component condensate, the formation of the K...The dynamics of spin–orbit-coupled Bose–Einstein condensate with parity-time symmetry through a moving obstacle potential is simulated numerically. In the miscible two-component condensate, the formation of the Kármán vortex street is observed in one component, while ‘the half-quantum vortex street' is observed in the other component. Other patterns of vortex shedding, such as oblique vortex dipoles, V-shaped vortex pairs, irregular turbulence, and combined modes of various wakes, can also be found. The ratio of inter-vortex spacing in one row to the distance between vortex rows is approximately0.18, which is less than the stability condition 0.28 of classical fluid. The drag force acting on the obstacle potential is simulated. The parametric regions of Kármán vortex street and other vortex patterns are calculated. The range of Kármán vortex street is surrounded by the region of combined modes. In addition, spin–orbit coupling disrupts the symmetry of the system and the gain-loss affects the local particle distribution of the system, which leads to the local symmetry breaking of the system, and finally influences the stability of the Kármán vortex street. Finally, we propose an experimental protocol to realize the Kármán vortex street in a system.展开更多
The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks ca...The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks can outweigh the benefits. A cross-sectional study was conducted in the Bamako district, focusing on street food vendors near schools, universities, extensive markets, administrative centers, and major roads. We aimed to sample fifty (50) sellers per municipality, making 300 sellers for the Bamako district. We developed a survey sheet to collect data, and six teams rotated between the municipalities each month. Before starting the collection, the teams were provided administrative papers approved by the municipal authority. The survey revealed three types of sales sites: fixed (65%), semi-fixed (30%), and mobile (4.40%). The proportion of sellers was 26.8%, 23.2%, 19.7%, and 4.2% in municipalities III, IV, and I. In municipalities I, II, III, IV, and VI, respectively, 92%, 95.70%, 93%, 87.2%, and 100% of the sellers were female. The age distribution of sellers was 65.63%, 46.81%, 40.82%, 38.30%, 36.17%, 36%, and 32% in the 25-34 and 35 - 44 age groups. Illiteracy rates were 59.20%, 61.70%, 55.30%, 75%, and 56% in municipalities I, II, III, IV, and VI, respectively. The study identified two categories of sellers: 48.3% in type 1 and 51.7% in type 2. The first category comprised 154 sellers, and the second 165 sellers. The survey found that 66.00%, 56.00%, 48.90%, 44.90%, 38.30%, and 34.40% of municipal V, VI, III, I, II, and IV sales sites were open-air. In municipality I, 63.30% of the sites were under hangars, while in municipalities II and IV, the corresponding percentages were 51.10% and 59.40%, respectively. Moreover, 46.00%, 31.90%, 31.30%, 30.60%, and 27.70% of the sites in municipalities VI, II, IV, I, and III were located next to gutters. In conclusion, this study identified several factors that could compromise the quality of street foods sold in the six municipalities of Bamako.展开更多
Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side custome...Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side customers including general public, shopping personals, tourists, students. In our country, street vendors crushing sugarcane between roller crusher and sold without any heat treatment or preservative, also served with or without added ice and lemon juice. The study aimed to identify and compare the physico-chemical and microbial quality of sugarcane juice. The chemical qualities of juices including moisture, P<sup>H</sup>, ash, total soluble solid, total sugar, reducing sugar and titrable acidity were found slightly different in Mymensingh, Gazipur and Narayangonj areas. The highest and lowest value of moisture, ash, P<sup>H</sup>, total soluble solids, total sugar, reducing sugar and titrable acidity were found in 84.33% - 79.26% (Gazipur-Mymensingh), 0.57% - 0.04% (Mymensingh-Gazipur), 5.9 - 2.9 (Gazipur-Narayangonj), 17.48% - 4.98% (Mymensingh-Narayangonj), 21.9% - 6.56% (Mymensingh-Gazipur), 3.7 - 2.1 (Gazipur-Mymensingh) and 0.523% - 0.007% (Narayangonj-Gazipur) respectively. For microbiological analysis, the total viable count of sugar cane juice in Mymensingh, Gazipur and Narayangonj were ranged from 0.6 × 10<sup>5</sup> - 43.6 × 10<sup>5</sup> cfu/ml, 4.6 × 10<sup>5</sup> - 21.6 × 10<sup>5</sup> cfu/ml and 3.6 × 10<sup>5</sup> - 36.6 × 10<sup>5</sup> cfu/ml respectively, where the permitted value is 1.0 × 10<sup>4</sup> cfu/ml, whereas the total coliform count was ranged from 0.4 × 10<sup>5</sup> - 6.4 × 10<sup>5</sup> cfu/ml, 0.6 × 10<sup>5</sup> - 8.4 × 10<sup>5</sup> cfu/ml and 0.00 - 8.4 × 10<sup>5</sup> cfu/ml, where the permitted value is 100 cfu/ml and total fungal count was ranged from 5.5 × 10<sup>5</sup> - 56.5 × 10<sup>5</sup> cfu/ml, 21.5 × 10<sup>5</sup> - 54.5 × 10<sup>5</sup> cfu/ml and 32.5 × 10<sup>5</sup> - 68.5 × 10<sup>5</sup> cfu/ml, where the permitted value is 1000 cfu/ml. According to the Gulf standard, the microbiological parameters of all the collected sugar cane juice were out of the permitted standards, so that a serious health outbreak can be caused anytime.展开更多
Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street...Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street is a linear element of urban public space, and it is of great significance forimproving the quality of urban public space by studying the micro renewal design strategy of street space.Based on the interpretation of two urban renewal cases, Wangjing Street in Beijing and Mengzhuiwan inChengdu, taking Baihuazhou area in Nanchang City as an example, this paper analyzes the main problemsin the current situation of street space in Baihuazhou area from three aspects: space use, traffic organization,and waterfront space creation, and explores the micro renewal design strategy of the street space.展开更多
Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,...Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,Xicheng District of Beijing served as a national pilot of the 15-minute radius livelihood service circle.Based on the data of POI,urban walking network and building outline,this paper studies the coverage of commercial service facilities in the 15-minute radius livelihood service circle of Chunshu Street by using kernel density analysis and urban network analysis tools.The research shows that the commercial facilities are concentrated in Zhuangsheng Square and Dazhalan commercial district.There are large gaps in housekeeping and couriers logistics facilities,which need to be further improved.展开更多
With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cit...With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city.展开更多
On a cold morning,I inadvertently opened a door-the door of oblivion…In a flash,I found myself on a street.Two big words appeared before my eyes:“Time Street”.But there were few people on the street,and it was not ...On a cold morning,I inadvertently opened a door-the door of oblivion…In a flash,I found myself on a street.Two big words appeared before my eyes:“Time Street”.But there were few people on the street,and it was not as I had imagined.展开更多
Based on the five elements of urban intention,the ways of building the order of the public space of historical and cultural commercial streets were analyzed,and the process of visiting historical and cultural commerci...Based on the five elements of urban intention,the ways of building the order of the public space of historical and cultural commercial streets were analyzed,and the process of visiting historical and cultural commercial streets was compared to an article,which has a sequence relationship of beginning,transition,and end.In combination with the analysis of the order design of the public space in Wanshougong Historical and Cultural Street in Nanchang,the reasons why Wanshougong can conform to the development of the times,perfectly integrate with the contemporary city,perfectly connect with the past history and future development,and reflect the design concept of people-oriented and sustainable development of historical and cultural commercial streets were discussed.展开更多
Value-added services in recent networks are provided with smart grid technology and particularly smart street lighting.The effective management of services and networks,structured as smart,imposes development of manag...Value-added services in recent networks are provided with smart grid technology and particularly smart street lighting.The effective management of services and networks,structured as smart,imposes development of management information model,which meets the requirements of network operator,service provider,and subscribers.Paradigm of smart grid defines only management framework without specification of architecture model and functions.The bright deployment of smart grid is based on development of management models.To this moment they are short specialized,cover only some of management functional areas,and reflect partially the actors’requirements.This paper represents implementation aspects of models for service management and network management in smart street lighting.Object-oriented method is used by models’design.Management functions for services and network are considered in installation,provision,configuration,maintenance,security,accounting,and performance.The focus is on problems regarding optimization of developed models and their reducing to Boyce-Codd Normal Form.The procedures for Service Installation and Service Provision are demonstrated with different methods:direct method and method with decomposition.The paper is intended to business developers,university professors,and students.展开更多
This project adopts an advanced microcontroller as the core control unit,which accurately commands the servo drive,realizes the real-time light chasing and charging function of the solar panel,and effectively manages ...This project adopts an advanced microcontroller as the core control unit,which accurately commands the servo drive,realizes the real-time light chasing and charging function of the solar panel,and effectively manages the power supply system of the street light.At the same time,the system is able to continuously monitor the operation status of the servo within the range of 0°to 180°to ensure that it is trouble-free and not offline.The hardware system construction consists of five modules:a power module,solar panel module,servo module,street light module,and Organic Light-Emitting Diode(OLED)display module.Each module works together to support the stable operation of the whole system.The system workflow is to accurately determine the direction of the light source by collecting real-time light intensity data through four precision photoresistors.Subsequently,the microcontroller intelligently controls the helm module based on these data to drive the solar panel to rotate within a range of 180°to accurately track the sun’s orientation.The street light provides two lighting modes,automatic and manual,to meet the needs of different scenarios.During the daytime,the solar panels work actively to monitor and collect solar energy efficiently in real-time,meanwhile,when night falls,the solar panels switch to standby mode and the streetlights light up automatically,illuminating the road ahead for pedestrians.Compared with the traditional solar street lights on the market,the intelligent solar light chasing road system introduced in this project has significant advantages.Its unique light-chasing algorithm enables the solar panel to continuously track the light source from sunrise to sunset,thus significantly improving the charging efficiency.Compared with traditional street lights,the biggest advantage of this project is the proposed light-chasing algorithm,which can always charge from sunrise until sunset,making the charging efficiency increase by 38%to 47%.The charging efficiency is 20%to 38%higher than that of traditional street lamps.Simultaneously,the biggest advantage of this project is that the power storage capacity is higher than 35%of the traditional solar street light.Bringing users a more durable and stable lighting experience.展开更多
The study adopts Byram’s Intercultural Communicative Competence(ICC)model as the theoretical framework,and structured interviews were conducted to explore the impact of street interviews on the participants’ICC.Anal...The study adopts Byram’s Intercultural Communicative Competence(ICC)model as the theoretical framework,and structured interviews were conducted to explore the impact of street interviews on the participants’ICC.Analysis results revealed street interviews help students acquire knowledge in intercultural attitudes,intercultural knowledge,skills of discovery and interaction,and critical cultural awareness,aligning with the four components of Byram’s ICC model.Meanwhile,they have positive perceptions of street interviews.Therefore,street interviews have a positive effect on the development of participants’ICC.展开更多
As the basic unit of urban system,street is not only an important traffi c link in the city,but also an important carrier refl ecting urban life.As one of the public spaces in the city,streets provide places for vario...As the basic unit of urban system,street is not only an important traffi c link in the city,but also an important carrier refl ecting urban life.As one of the public spaces in the city,streets provide places for various outdoor activities,such as leisure,shopping,social contact and commercial publicity.The number of people and the duration that people stay in the streets for various activities constitute the vitality of streets.The vitality of streets can also be regarded as the vitality of cities to a certain extent.As one of the key infl uencing factors of street vitality,street traffi c accessibility has important research value.Based on the perspective of street traffi c accessibility,the dynamic factors affecting life streets are explored,and the design method of shaping street vitality is discussed through the analysis of practical cases in Nanchang City.展开更多
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 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 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.
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.
文摘The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent years,with the technological and economic development,smart street lighting has gradually emerged.Key functions of smart street lighting include road illumination,cultural promotion,meteorological monitoring,public broadcasting,and 5G micro-base stations.The overall quality of smart street lighting construction directly impacts the effectiveness of urban development and the city’s comprehensive growth.This paper analyzes the concept of smart street lighting,its advantages and disadvantages,the functionalities of smart street light systems,and the application of smart street lighting in urban road illumination.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12065022 and 12147213)。
文摘The dynamics of spin–orbit-coupled Bose–Einstein condensate with parity-time symmetry through a moving obstacle potential is simulated numerically. In the miscible two-component condensate, the formation of the Kármán vortex street is observed in one component, while ‘the half-quantum vortex street' is observed in the other component. Other patterns of vortex shedding, such as oblique vortex dipoles, V-shaped vortex pairs, irregular turbulence, and combined modes of various wakes, can also be found. The ratio of inter-vortex spacing in one row to the distance between vortex rows is approximately0.18, which is less than the stability condition 0.28 of classical fluid. The drag force acting on the obstacle potential is simulated. The parametric regions of Kármán vortex street and other vortex patterns are calculated. The range of Kármán vortex street is surrounded by the region of combined modes. In addition, spin–orbit coupling disrupts the symmetry of the system and the gain-loss affects the local particle distribution of the system, which leads to the local symmetry breaking of the system, and finally influences the stability of the Kármán vortex street. Finally, we propose an experimental protocol to realize the Kármán vortex street in a system.
文摘The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks can outweigh the benefits. A cross-sectional study was conducted in the Bamako district, focusing on street food vendors near schools, universities, extensive markets, administrative centers, and major roads. We aimed to sample fifty (50) sellers per municipality, making 300 sellers for the Bamako district. We developed a survey sheet to collect data, and six teams rotated between the municipalities each month. Before starting the collection, the teams were provided administrative papers approved by the municipal authority. The survey revealed three types of sales sites: fixed (65%), semi-fixed (30%), and mobile (4.40%). The proportion of sellers was 26.8%, 23.2%, 19.7%, and 4.2% in municipalities III, IV, and I. In municipalities I, II, III, IV, and VI, respectively, 92%, 95.70%, 93%, 87.2%, and 100% of the sellers were female. The age distribution of sellers was 65.63%, 46.81%, 40.82%, 38.30%, 36.17%, 36%, and 32% in the 25-34 and 35 - 44 age groups. Illiteracy rates were 59.20%, 61.70%, 55.30%, 75%, and 56% in municipalities I, II, III, IV, and VI, respectively. The study identified two categories of sellers: 48.3% in type 1 and 51.7% in type 2. The first category comprised 154 sellers, and the second 165 sellers. The survey found that 66.00%, 56.00%, 48.90%, 44.90%, 38.30%, and 34.40% of municipal V, VI, III, I, II, and IV sales sites were open-air. In municipality I, 63.30% of the sites were under hangars, while in municipalities II and IV, the corresponding percentages were 51.10% and 59.40%, respectively. Moreover, 46.00%, 31.90%, 31.30%, 30.60%, and 27.70% of the sites in municipalities VI, II, IV, I, and III were located next to gutters. In conclusion, this study identified several factors that could compromise the quality of street foods sold in the six municipalities of Bamako.
文摘Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side customers including general public, shopping personals, tourists, students. In our country, street vendors crushing sugarcane between roller crusher and sold without any heat treatment or preservative, also served with or without added ice and lemon juice. The study aimed to identify and compare the physico-chemical and microbial quality of sugarcane juice. The chemical qualities of juices including moisture, P<sup>H</sup>, ash, total soluble solid, total sugar, reducing sugar and titrable acidity were found slightly different in Mymensingh, Gazipur and Narayangonj areas. The highest and lowest value of moisture, ash, P<sup>H</sup>, total soluble solids, total sugar, reducing sugar and titrable acidity were found in 84.33% - 79.26% (Gazipur-Mymensingh), 0.57% - 0.04% (Mymensingh-Gazipur), 5.9 - 2.9 (Gazipur-Narayangonj), 17.48% - 4.98% (Mymensingh-Narayangonj), 21.9% - 6.56% (Mymensingh-Gazipur), 3.7 - 2.1 (Gazipur-Mymensingh) and 0.523% - 0.007% (Narayangonj-Gazipur) respectively. For microbiological analysis, the total viable count of sugar cane juice in Mymensingh, Gazipur and Narayangonj were ranged from 0.6 × 10<sup>5</sup> - 43.6 × 10<sup>5</sup> cfu/ml, 4.6 × 10<sup>5</sup> - 21.6 × 10<sup>5</sup> cfu/ml and 3.6 × 10<sup>5</sup> - 36.6 × 10<sup>5</sup> cfu/ml respectively, where the permitted value is 1.0 × 10<sup>4</sup> cfu/ml, whereas the total coliform count was ranged from 0.4 × 10<sup>5</sup> - 6.4 × 10<sup>5</sup> cfu/ml, 0.6 × 10<sup>5</sup> - 8.4 × 10<sup>5</sup> cfu/ml and 0.00 - 8.4 × 10<sup>5</sup> cfu/ml, where the permitted value is 100 cfu/ml and total fungal count was ranged from 5.5 × 10<sup>5</sup> - 56.5 × 10<sup>5</sup> cfu/ml, 21.5 × 10<sup>5</sup> - 54.5 × 10<sup>5</sup> cfu/ml and 32.5 × 10<sup>5</sup> - 68.5 × 10<sup>5</sup> cfu/ml, where the permitted value is 1000 cfu/ml. According to the Gulf standard, the microbiological parameters of all the collected sugar cane juice were out of the permitted standards, so that a serious health outbreak can be caused anytime.
文摘Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street is a linear element of urban public space, and it is of great significance forimproving the quality of urban public space by studying the micro renewal design strategy of street space.Based on the interpretation of two urban renewal cases, Wangjing Street in Beijing and Mengzhuiwan inChengdu, taking Baihuazhou area in Nanchang City as an example, this paper analyzes the main problemsin the current situation of street space in Baihuazhou area from three aspects: space use, traffic organization,and waterfront space creation, and explores the micro renewal design strategy of the street space.
文摘Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,Xicheng District of Beijing served as a national pilot of the 15-minute radius livelihood service circle.Based on the data of POI,urban walking network and building outline,this paper studies the coverage of commercial service facilities in the 15-minute radius livelihood service circle of Chunshu Street by using kernel density analysis and urban network analysis tools.The research shows that the commercial facilities are concentrated in Zhuangsheng Square and Dazhalan commercial district.There are large gaps in housekeeping and couriers logistics facilities,which need to be further improved.
基金National Natural Science Foundation of China(51708004)Beijing Youth Teaching Elite Team Construction Project(108051360023XN261)North China University of Technology Yuyou Talent Training Program(215051360020XN160/009).
文摘With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city.
文摘On a cold morning,I inadvertently opened a door-the door of oblivion…In a flash,I found myself on a street.Two big words appeared before my eyes:“Time Street”.But there were few people on the street,and it was not as I had imagined.
文摘Based on the five elements of urban intention,the ways of building the order of the public space of historical and cultural commercial streets were analyzed,and the process of visiting historical and cultural commercial streets was compared to an article,which has a sequence relationship of beginning,transition,and end.In combination with the analysis of the order design of the public space in Wanshougong Historical and Cultural Street in Nanchang,the reasons why Wanshougong can conform to the development of the times,perfectly integrate with the contemporary city,perfectly connect with the past history and future development,and reflect the design concept of people-oriented and sustainable development of historical and cultural commercial streets were discussed.
文摘Value-added services in recent networks are provided with smart grid technology and particularly smart street lighting.The effective management of services and networks,structured as smart,imposes development of management information model,which meets the requirements of network operator,service provider,and subscribers.Paradigm of smart grid defines only management framework without specification of architecture model and functions.The bright deployment of smart grid is based on development of management models.To this moment they are short specialized,cover only some of management functional areas,and reflect partially the actors’requirements.This paper represents implementation aspects of models for service management and network management in smart street lighting.Object-oriented method is used by models’design.Management functions for services and network are considered in installation,provision,configuration,maintenance,security,accounting,and performance.The focus is on problems regarding optimization of developed models and their reducing to Boyce-Codd Normal Form.The procedures for Service Installation and Service Provision are demonstrated with different methods:direct method and method with decomposition.The paper is intended to business developers,university professors,and students.
文摘This project adopts an advanced microcontroller as the core control unit,which accurately commands the servo drive,realizes the real-time light chasing and charging function of the solar panel,and effectively manages the power supply system of the street light.At the same time,the system is able to continuously monitor the operation status of the servo within the range of 0°to 180°to ensure that it is trouble-free and not offline.The hardware system construction consists of five modules:a power module,solar panel module,servo module,street light module,and Organic Light-Emitting Diode(OLED)display module.Each module works together to support the stable operation of the whole system.The system workflow is to accurately determine the direction of the light source by collecting real-time light intensity data through four precision photoresistors.Subsequently,the microcontroller intelligently controls the helm module based on these data to drive the solar panel to rotate within a range of 180°to accurately track the sun’s orientation.The street light provides two lighting modes,automatic and manual,to meet the needs of different scenarios.During the daytime,the solar panels work actively to monitor and collect solar energy efficiently in real-time,meanwhile,when night falls,the solar panels switch to standby mode and the streetlights light up automatically,illuminating the road ahead for pedestrians.Compared with the traditional solar street lights on the market,the intelligent solar light chasing road system introduced in this project has significant advantages.Its unique light-chasing algorithm enables the solar panel to continuously track the light source from sunrise to sunset,thus significantly improving the charging efficiency.Compared with traditional street lights,the biggest advantage of this project is the proposed light-chasing algorithm,which can always charge from sunrise until sunset,making the charging efficiency increase by 38%to 47%.The charging efficiency is 20%to 38%higher than that of traditional street lamps.Simultaneously,the biggest advantage of this project is that the power storage capacity is higher than 35%of the traditional solar street light.Bringing users a more durable and stable lighting experience.
文摘The study adopts Byram’s Intercultural Communicative Competence(ICC)model as the theoretical framework,and structured interviews were conducted to explore the impact of street interviews on the participants’ICC.Analysis results revealed street interviews help students acquire knowledge in intercultural attitudes,intercultural knowledge,skills of discovery and interaction,and critical cultural awareness,aligning with the four components of Byram’s ICC model.Meanwhile,they have positive perceptions of street interviews.Therefore,street interviews have a positive effect on the development of participants’ICC.
文摘As the basic unit of urban system,street is not only an important traffi c link in the city,but also an important carrier refl ecting urban life.As one of the public spaces in the city,streets provide places for various outdoor activities,such as leisure,shopping,social contact and commercial publicity.The number of people and the duration that people stay in the streets for various activities constitute the vitality of streets.The vitality of streets can also be regarded as the vitality of cities to a certain extent.As one of the key infl uencing factors of street vitality,street traffi c accessibility has important research value.Based on the perspective of street traffi c accessibility,the dynamic factors affecting life streets are explored,and the design method of shaping street vitality is discussed through the analysis of practical cases in Nanchang City.
