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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China
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作者 WANG Zili LU Chunyan +4 位作者 SU Yanlin SU Yue YU Qianru LI Wenzhe YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2024年第1期135-148,共14页
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human... Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development. 展开更多
关键词 winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City China
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SUSTAINABLE URBAN-RURAL RELATION IN RAPID URBANIZATION AREAS——Case of Transformation of "Urban Village" in Guangzhou
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作者 WEI Li-hua YAN Xiao-pei 《Chinese Geographical Science》 SCIE CSCD 2005年第3期212-218,共7页
Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. ... Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. However, most of these studies started mainly from the standpoint of the city govemment, drumming for the land- scape-oriented urbanization, namely pulling-down the urban village and constructing the splendid residence or business buildings. The article maintains that the most important thing the city government should do is to pay much attention to the sustainable living of urban villagers, who would lose their main income source, namely, the collective dividend and the family housing rent. The single method of compensation has been proved to be harmful to the villagers' community, in which some young villagers relying on rent were no longer to do anything but stay at home. On the other hand, considering the floating population has become the main stream of renters in urban villages, the emergence of urban villages was inevitable and would continue to exist in a long time under the socio-economic transition in urban China and globalization. Based on the analysis above, the transformation of urban village should take more concerns on the housing demands of floating population besides compensation for local villagers. Meanwhile, it is necessary to avoid the “landscape-oriented urbanization” without the “peasant-to-citizen” transformation. 展开更多
关键词 urban-rural relation rapid urbanization areas GUANGZHOU urban village
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The Evolution of Landscape Patterns of and Optimization Measures for Urban Core Areas Against the Background of Urbanization: A Case Study of Yangling Demonstration Zone
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作者 TANG Ying ZHANG Pei SHI Chengyong 《Journal of Landscape Research》 2018年第4期67-71,77,共6页
Studying tiie urban landscape pattern plays a crucial role in scientific land use and management and in improving the urban ecological environment In this paper, AutoCAD, ArcGIS, Fragstats, and other software were u... Studying tiie urban landscape pattern plays a crucial role in scientific land use and management and in improving the urban ecological environment In this paper, AutoCAD, ArcGIS, Fragstats, and other software were used to analyse the data of the fourth phase of land use in the core atea of Yangling Demonstration Zone. The results showed that: ① in the core area, the percentage of construction land incteased from 18.22% to 61.72%, and the percentage of agricultufal land decreased from 58.36% to 11.14%. And the fafm land was fragmented, and traffic connectivily was strengthened. The afea of garden land was reduced from 251.89 hm2 to 50.38 hm^2, and the landscape metric of forest land showed an inverted V-shaped curve. ②The year 2009 in four phases witnessed the greatest landscape fragmentation, both Edge Density (ED) and Ingest Patch Index (LPI) increased, and human interference enhanced the overall landscape complexity. Measures were fotmulated in terms of deaf development goals, optimized allocation of land resoutces, effective protection of ecological ted lines, and definite ecological responsibility, so as to optimize the urban landscape pattern. 展开更多
关键词 Yangling Demonstration Zone Urban core area Changes in landscape patterns Optimization measures
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Mutual Conversion of Land Use between Urban and Rural Area in the Process of Urbanization: A Case Study of Shandong Province
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作者 Xu Hong College of Population, Resource and Environment, Shandong Normal University, Jinan Shandong 250014, China 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第2期93-96,共4页
Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze th... Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization. 展开更多
关键词 mutual conversion of land use between urban and rural areas structure of land use flow of the cultivated land
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Metropolitan Housing Development in Urban Fringe Areas-A Case Study of Three Metropolitan Cities of South Africa: Johannesburg, Ekurhuleni and Tshwane 被引量:1
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作者 Aurobindo Ogra 《Journal of Civil Engineering and Architecture》 2024年第5期244-253,共10页
Purpose:The metropolitan cities of Johannesburg,Ekurhuleni and Tshwane play an important role in the economy of the Gauteng province in South Africa.The region constitutes to 22.4 percent of the total population of So... Purpose:The metropolitan cities of Johannesburg,Ekurhuleni and Tshwane play an important role in the economy of the Gauteng province in South Africa.The region constitutes to 22.4 percent of the total population of South Africa and has a strong presence and contributes in areas of manufacturing sector,financial and business services,retail and wholesale trade,etc.The rapid urban population,increase in the informal settlements and socio-economic opportunities has resulted in considerable urban sprawl in and around the urban fringe areas of these metropolitan cities.The urban fringe areas of these metros often come under the influence of rapid urbanization process and pressures.Coupled with the economical and potential land dynamics and lack of priority of spatial development guidelines,these areas attract rapid and haphazard development from communities and developers.Research Design/Methodology:This research is based on a qualitative approach through a comprehensive literature review that included content analysis of key documents on housing sector such as IDPs(Integrated Development Plans),Municipal Annual Reports,Growth Development Strategies,and among other sectoral documents on housing sector.Some of the key priority issues considered in the housing sector included:eradication of housing backlogs,spatial restructuring of housing,provision of choice in terms of location,tenure and housing typology.Findings:The current paper discusses the approaches of metropolitan housing development processes in three metropolitan cities of South Africa from Gauteng region,namely:Johannesburg,Ekurhuleni and Tshwane.The paper discusses the existing housing sectoral scenario along with the fringe areas in three cities with focus on:formal and informal settlements,housing segregation and the backlogs,current institutional arrangements,role of public private participation,and scope for alternate mechanisms.The paper concludes in discussion on sustainable development options for housing development in urban fringe areas. 展开更多
关键词 Metropolitan housing development urban fringe areas housing backlog informal settlements urban poor land dynamics housing infrastructure PPP(public private partnership)
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Exploring well-being disparities between urban and rural areas:A case study in the Stavropol Territory,Russia
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作者 Anastasia CHAPLITSKAYA Wim HEIJMAN Johan van OPHEM 《Regional Sustainability》 2024年第1期80-92,共13页
Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially importa... Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially important in countries where agricultural production accounts for a significant share of the gross product,such as Russia.In this study,we identified the key indicators of satisfaction and differences between rural and urban citizens based on their social,economic,and environmental backgrounds,and determined whether there are well-being disparities between rural and urban areas in the Stavropol Territory,Russia.We collected primary data through a survey based on the European Social Survey framework to investigate the potential differences between rural and urban areas.By computing the regional well-being index using principal component analysis,we found that there was no statistically significant difference in well-being between rural and urban areas.Results of key indicators showed that rural residents felt psychologically more comfortable and safer,assessed their family relationships better,and adhered more to traditions and customs.However,urban residents showed better economic and social conditions(e.g.,infrastructures,medical care,education,and Internet access).The results of this study imply that we can better understand the local needs,advantages,and unique qualities,thereby gaining insight into the effectiveness of government programs.Policy-makers and local authorities can consider targeted interventions based on the findings of this study and strive to enhance the well-being of both urban and rural residents. 展开更多
关键词 WELL-BEING Sustainable development Rural areas Urban areas Principal component analysis(PCA) RUSSIA
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Mapping ecosystem services in urban and peri-urban areas.A systematic review
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作者 Paulo Pereira Miguel Inácio +3 位作者 Luis Pinto Marius Kalinauskas Katarzyna Bogdzevic Wenwu Zhao 《Geography and Sustainability》 CSCD 2024年第3期491-509,共19页
Urban and peri-urban ecosystems are subjected to an intense impact.The demand for ecosystem services(ES)is higher in these areas.Nevertheless,despite the anthropogenic pressures,urban and peri-urban ecosystems supply ... Urban and peri-urban ecosystems are subjected to an intense impact.The demand for ecosystem services(ES)is higher in these areas.Nevertheless,despite the anthropogenic pressures,urban and peri-urban ecosystems supply important ES.Mapping is a crucial exercise to understand ES dynamics in these environments better.This work aims to systematically review mapping ES in urban and peri-urban areas studies,following the Preferred Reporting Items for Systematic Reviews and Meta-alpha Methods.A total of 207 studies were selected.The results show increased work between 2011 and 2023,mainly conducted in Europe and China.Most work were developed in urban areas and did not follow an established ES classification.Most studies focused on the ES supply dimension,the regulation and maintenance section.Regarding provisioning ES,most studies focused on Cultivating terrestrial plants for nutrition,regulating and maintainin g Atmospheric composition and conditions,and for cultural ES on Physical and experiential interactions with the natural environment.Quantitative methods were mostly applied following Indicator-based(secondary data:biophysical,socio-economic)models.Very few work validated the outputs.Several studies forecasted ES,primarily based on land use changes using CA-Markov approaches.This study provides an overview of the most mapped urban and peri-urban ES globally,the areas where more studies need to be conducted,and the methods developed. 展开更多
关键词 Systematic review Urban and peri-urban areas Ecosystem services MAPPING METHODS
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Analysis of Strategies to Improve Traffic Conditions in the Ancient Urban Area of Suzhou 被引量:2
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作者 曹国华 崔功豪 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期148-153,共6页
In this paper, the authors first analyse the problems existing in the situation of land use, structure of travel mode and road network by applying the basic principle of traffic engineering and system engineering meth... In this paper, the authors first analyse the problems existing in the situation of land use, structure of travel mode and road network by applying the basic principle of traffic engineering and system engineering methods. Then, the authors make it clear the strategies to be adopted for solving the existing traffic problems in the ancient urban area of Suzhou(AUAS), namely insisting on the goal based strategy; the strategy to develop the public transit system in priority and decreasing the demand on cars from the view point of land use strategy. On the basis of such analysis the authors put forth proposals about major measures to be taken to improve traffic conditions of the AUAS, such as construction of express artery ring around the ancient city, appropriate transformation of the roads in the AUAS and rational distribution of car parking areas at the outskirt, which are of positive significance in guiding the protection of the AUAS and transportation construction. In this paper, specialized software is used to establish criteria for the construction scale and extent analysis and evaluation of the ancient city construction project, which is of some reference significance to the transformation of old urban areas in other cities. 展开更多
关键词 ancient urban area of Suzhou traffic problems STRATEGY
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Numerical Study on the Impacts of Heterogeneous Reactions on Ozone Formation in the Beijing Urban Area 被引量:15
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作者 徐峻 张远航 王玮 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第4期605-614,共10页
The air quality model CMAQ-MADRID (Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution) was employed to simulate summer O3 formation in Beijing China, in order to explore... The air quality model CMAQ-MADRID (Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution) was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO→NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations. 展开更多
关键词 heterogeneous reactions OZONE air quality model IMPACTS urban area
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Pollutant loads of surface runoff in Wuhan City Zoo, an urban tourist area 被引量:23
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作者 ZHAO Jian-wei SHAN Bao-qing YIN Cheng-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第4期464-468,共5页
The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one ro... The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one road, were selected for sampling and study. The results indicate that pollutants ranked in a predictable order of decreasing load (e.g. animal yard〉roof〉woodland〉road), with animal yards acting as the key pollution source in the zoo. Pollutants were transported mainly by particulate form in runoff. Particulate nitrogen and particulate phosphorous accounted on average for 61%, 78% of total pollutant, respectively, over 13 monitored rainfall events. These results indicate the treatment practices should be implemented to improve particulate nutrient removal. Analysis of the M(V) curve indicate that no first flush effect existed in the surface runoff from pervious areas (e.g. woodland, animal ground yard), whereas a first flush effect was evident in runoff from impervious surfaces (e.g. animal cement yard, roof, road). 展开更多
关键词 surface runoff stormwater pollution urban tourist area impervious/pervious surface M(V) curve
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Construction of green infrastructure in coal-resource based city: a case study in Xuzhou urban area 被引量:9
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作者 Jiang Chang Tinghao Hu +1 位作者 Xiangxu Liu Xiaogeng Ren 《International Journal of Coal Science & Technology》 EI 2018年第1期92-104,共13页
As an important coal-resource based city in eastern China, coal mining activities have greatly promoted economic development to Xuzhou while resulted in kinds of blocks for sustainable development. Subsidence areas ca... As an important coal-resource based city in eastern China, coal mining activities have greatly promoted economic development to Xuzhou while resulted in kinds of blocks for sustainable development. Subsidence areas caused by coal mining activities and rapid urbanization process led to the losing of ecological function and decreasing of landscape connectivity in the city. As the important life-support system, urban green infrastructure (GI as short) has great significance in improving human well-beings. Taking Xuzhou urban area as the study object, this paper proposed a green infrastructure construction method based on the principle of ecological priority. Firstly, key ecological patches were identified by GIS and RS methods. Secondly, we established corridors by minimum cost path model. Then, we built GI network and evaluated the ecological importance of different patches. Finally, by comparing the status of patches and coal mining subsidence areas, we proposed a framework for constructing GI network in Xuzhou urban area. 展开更多
关键词 Coal-resource based city Green infrastructure Green space Xuzhou urban area
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Characterization of Air Pollution in Urban Areas of Yangtze River Delta,China 被引量:7
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作者 CHEN Tan DENG Shulin +3 位作者 GAO Yu QU Lean LI Manchun CHEN Dong 《Chinese Geographical Science》 SCIE CSCD 2017年第5期836-846,共11页
The hallmark of development in the Yangtze River Delta(YRD) of East China has been sprawling urbanization. However, air pollution is a significant problem in these urban areas. In this paper, we investigated and analy... The hallmark of development in the Yangtze River Delta(YRD) of East China has been sprawling urbanization. However, air pollution is a significant problem in these urban areas. In this paper, we investigated and analyzed the air pollution index(API) in four cities(Shanghai, Nanjing, Hangzhou and Ningbo) in the YRD from 2001 to 2012. We attempted to empirically examine the relationship between meteorological factors and air quality in the urban areas of the YRD. According to the monitoring data, the API in Shanghai, Nanjing, Hangzhou slightly declined and that in Ningbo increased over the study period. We analyzed the inter-annual, seasonal, and monthly variations of API, from which we found that the air quality had different temporal changes in the four cities. It was indicated that air quality was poor in winter and spring and best in summer. Furthermore, different weather conditions affected air quality level. The wind direction was considered as an important and influential factor to air pollution, which has an impact on the accumulating or cleaning processes of pollutants. The air quality was influenced by the different wind directions that varied with seasons and cities. 展开更多
关键词 air pollution index (API) urban area meteorological factor environmental decision Yangtze River Delta China
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Multi-source Data-driven Identification of Urban Functional Areas:A Case of Shenyang,China 被引量:3
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作者 XUE Bing XIAO Xiao +2 位作者 LI Jingzhong ZHAO Bingyu FU Bo 《Chinese Geographical Science》 SCIE CSCD 2023年第1期21-35,共15页
Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of ... Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of human-land interaction.In this paper,based on multi-source big data include 250 m×250 m resolution cell phone data,1.81×105 Points of Interest(POI)data and administrative boundary data,we built a UFA identification method and demonstrated empirically in Shenyang City,China.We argue that the method we built can effectively identify multi-scale multi-type UFAs based on human activity and further reveal the spatial correlation between urban facilities and human activity.The empirical study suggests that the employment functional zones in Shenyang City are more concentrated in central cities than other single functional zones.There are more mix functional areas in the central city areas,while the planned industrial new cities need to develop comprehensive functions in Shenyang.UFAs have scale effects and human-land interaction patterns.We suggest that city decision makers should apply multi-sources big data to measure urban functional service in a more refined manner from a supply-demand perspective. 展开更多
关键词 human-land relationship multi-source big data urban functional area identification method Shenyang City
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Estimating HIV Incidence Rates among MSM in an Urban Area of Chongqing Using Three Approaches 被引量:3
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作者 HAN Mei PAN Ping Liang +5 位作者 WU Guo Hui ZHOU Chao YAO Yuan LUO Juan ZOU Jing Bo ZHANG Bo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第12期913-916,共4页
To evaluate the HIV pandemic in Chongqing, the pooled PCR, IgG-capture BED enzyme immunoassay (BED-CEIA), and cohort observations were used to estimate the HIV incidences among men who have sex with men (MSM). 617... To evaluate the HIV pandemic in Chongqing, the pooled PCR, IgG-capture BED enzyme immunoassay (BED-CEIA), and cohort observations were used to estimate the HIV incidences among men who have sex with men (MSM). 617 MSM subjects completed the survey at a voluntary counseling and testing (VCT) site. The observed HIV incidence was 12.5 per 100 P-Ys (95% CI = 9.1-15.7). 展开更多
关键词 Estimating HIV Urban area
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Random walk modeling of wake dispersion for the exhaust tower of an underground tunnel in urban area 被引量:2
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作者 JIANG Wei\|mei\+1, YU Hong\|bin\+1, LI Xin\+2 (1.Department of Atmospheric Sciences, Nanjing University, Nanjing 210093, China 2.LAPC, Institute of Atmospheric Physics,Chinese Academy of Sciences, Beijing 100029, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第4期474-479,共6页
In this paper, some experimental studies on the impact of effluent from an exhaust tower of an underground tunnel with special construction are reported. By measuring the flow field downstream of the tower in NJU mete... In this paper, some experimental studies on the impact of effluent from an exhaust tower of an underground tunnel with special construction are reported. By measuring the flow field downstream of the tower in NJU meteorological wind tunnel, some flow characteristics in the make area were established. Based on these, an advanced random\|walk dispersion model was set up and applied successfully to the simulation of dispersion in the wake area. The modelling results were in accordance with wind tunnel measurements. The computed maximum of ground surface concentration in the building case was a factor of 3-4 higher than that in the flat case and appeared much closer to the source. The simulation indicated that random walk modelling is an effective and practical tool for the wake stream impact assessment. 展开更多
关键词 exhaust tower air pollution in urban area atmospheric dispersion random walk modelling
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Localization and mapping in urban area based on 3D point cloud of autonomous vehicles 被引量:2
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作者 王美玲 李玉 +2 位作者 杨毅 朱昊 刘彤 《Journal of Beijing Institute of Technology》 EI CAS 2016年第4期473-482,共10页
In order to meet the application requirements of autonomous vehicles, this paper proposes a simultaneous localization and mapping (SLAM) algorithm, which uses a VoxelGrid filter to down sample the point cloud data, ... In order to meet the application requirements of autonomous vehicles, this paper proposes a simultaneous localization and mapping (SLAM) algorithm, which uses a VoxelGrid filter to down sample the point cloud data, with the combination of iterative closest points (ICP) algorithm and Gaussian model for particles updating, the matching between the local map and the global map to quantify particles' importance weight. The crude estimation by using ICP algorithm can find the high probability area of autonomous vehicles' poses, which would decrease particle numbers, increase algorithm speed and restrain particles' impoverishment. The calculation of particles' importance weight based on matching of attribute between grid maps is simple and practicable. Experiments carried out with the autonomous vehicle platform validate the effectiveness of our approaches. 展开更多
关键词 simultaneous localization and mapping (SLAM) Rao-Blackwellized particle filter RB-PF) VoxelGrid filter ICP algorithm Gaussian model urban area
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Carbon Dioxide Concentration and Flux in an Urban Residential Area in Seoul,Korea 被引量:2
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作者 Moon-Soo PARK Seung Jin JOO Soon-Ung PARK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第5期1101-1112,共12页
The carbon dioxide (CO2) concentrations and fluxes measured at a height of 17.5 m above the ground by a sonic anemometer and an open-path gas analyzer at an urban residential site in Seoul, Korea from February 2011 ... The carbon dioxide (CO2) concentrations and fluxes measured at a height of 17.5 m above the ground by a sonic anemometer and an open-path gas analyzer at an urban residential site in Seoul, Korea from February 2011 to January 2012 were analyzed. The annual mean CO2 concentration was found to be 750 mg m-3, with a maximum monthly mean concentration of 827 mg m-3 in January and a minimum value of 679 mg m-3 in August. Meanwhile, the annual mean CO2 flux was found to be 0.45 mg m-2 s-1, with a maximum monthly mean flux of 0.91 mg m-2 s-1 in January and a minimum value of 0.19 mg m-2 s-1 in June. The hourly mean CO2 concentration was found to show a significant diurnal variation; a maximum at 0700-0900 LST and a minimum at 1400-1600 LST, with a large diurnal range in winter and a small one in summer, mainly caused by diurnal changes in mixing height, CO2 flux, and surface complexity. The hourly mean CO2 flux was also found to show a significant diurnal variation, but it showed two maxima at 0700-0900 LST and 2100-2400 LST, and two minima at 1100-1500 LST and 0300-0500 LST, mainly caused by a diurnal pattern in CO2 emissions and sinks from road traffic, domestic heating and cooking by liquefied natural gas use, and the different horizontal distribution of CO2 sources and sinks near the site. Differential advection with respect to wind direction was also found to be a cause of diurnal variations in both the CO2 concentration and flux. 展开更多
关键词 CO2 concentration CO2 flux liquefied natural gas (LNG) SEOUL urban residential area
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TOWARD ESTABLISHING THE CONCEPT OF PHYSICAL URBAN AREA IN CHINA 被引量:2
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作者 Zhou Yixing Shi Yulong(Department of Goography, Peking University, Beijing 100871People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第4期1-15,共15页
This paper makes a detailed analysis of the vanous drawbacks of the continued use of adwhnistrative area in dividing urban and rural areas in spite of the serious discrepancies between urban admnistrative boundaries a... This paper makes a detailed analysis of the vanous drawbacks of the continued use of adwhnistrative area in dividing urban and rural areas in spite of the serious discrepancies between urban admnistrative boundaries and the 'real' urban space in China. The autiors believe that to solve this problem, it is essential to establish the concept of physical urban area with both adaptability to Chinese situation and intemational comparability and use it as the basis of urban-rural division and statistics. It is proposed that physical urban area should be defined in terms of prescribed minimum population scale, dngee of nonaghculturalization and population density.Based on extensive substantive research and a classifiotion of the space figurations of Chinese cities and towns, a new scheme to classify physical urban areas is proposed. 展开更多
关键词 physical urban area city statistical area (CSA) town statistical area (TSA) urban-type residential area (UTRA)
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Relationship between NO_2 Concentration and Meteorological Factors in the Urban Area of Wanzhou District 被引量:1
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作者 Xiang Yingchun Zhang Liying +2 位作者 Mao Xiaozhen Ma Huiyan Qian Ruozhi 《Meteorological and Environmental Research》 CAS 2014年第3期22-25,共4页
Firstly,the daily variations of NO2 concentration in the urban area of Wanzhou in 2012 were analyzed,and then the relationship between NO2 concentration and meteorological factors( precipitation,atmospheric pressure,... Firstly,the daily variations of NO2 concentration in the urban area of Wanzhou in 2012 were analyzed,and then the relationship between NO2 concentration and meteorological factors( precipitation,atmospheric pressure,wind speed,temperature,relative humidity and sunshine hours) was discussed. Finally,the multiple linear regression equation was established to predict NO2 concentration. The results showed that NO2 concentration in the urban area of Wanzhou did not exceed 80 μg /m3in most days from January 1 to December 31 in 2012. Among the six meteorological factors,NO2 concentration correlated significantly with three meteorological factors,that is,NO2 concentration correlated negatively with atmospheric pressure and wind speed but positively with relative humidity. NO2 concentration in the urban area of Wanzhou could be predicted using the multiple linear regression model. According to the rose diagram of wind directions,the wind blowing from the NNW was dominant in the urban area of Wanzhou. 展开更多
关键词 Wanzhou Urban area Nitrogen dioxide Meteorological factors China
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Agricultural land loss in China's urbanization process 被引量:3
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作者 Li Xiaoyun Cai Yinyin +1 位作者 Zhu Daolin Zhang Anlu 《Ecological Economy》 2006年第1期32-41,共10页
In China, urbanization of agricultural land around city agglomerations increases rapidly. Rapid urbanization of agricultoral land affects food supply, land value and ecological balance in the society. In China, the ur... In China, urbanization of agricultural land around city agglomerations increases rapidly. Rapid urbanization of agricultoral land affects food supply, land value and ecological balance in the society. In China, the urban built-up area had increased by 40% from 1996 to 2003. This increase came predominantly from farmland surrounding the cities. How the ongoing urbanization of China affects its agricultural land is the focus of this paper. In current studies, we have found that population density; urbanization degree and personal income are key factors that influence the urbanization process. Based on this, relation model has been established and to predict the general trends of the urban area expansion in China in 2020.In 2020, the constructed urban area of China would be increased by 1.3 times compared wtth 2003. In 2020, this study anticipates the conversion of about 32,562 sq. kin. agricultural land of China for urban use. 展开更多
关键词 China Agricultural land conversion urbanization Constructed urban area Trends and forecast
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