During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil d...During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is located.The monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction areas.The former is the gathering point of the entire urban population.There are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation cover.Several existing items requiremonitoring.However,monitoring distance is long,and providing early warning is difficult.This study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence deformation.Then,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway operation.Results show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 mm.And FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation.展开更多
Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Pr...Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Project,research on HSR route selection in complicated urban areas has been conducted.An optimal route selection plan is determined after studying the local geological and environmental conditions and the complexity of tunnel construction.The research concludes that there are four major concerns in HSR route selection:the match between the new route and the urban planning,the potential economic return for the massive investment,the likely impacts of land expropriation on social stability,and the best synthesis of multiple controlling factors to meet the HSR standard.Moreover,six principles should be followed in railway route selection in complicated urban areas:the new route should be in alignment with the railway deployment;the route should align with the existing passage as much as possible;extensive analysis and in-depth demonstrations should be done to find the most appropriate combination of open and hidden excavation in tunnel construction;geological conditions and tunnel construction complexities are among the priorities;environmental sensitive sites and environmental vibration noise should be avoided as much as possible;special attention should be paid to the relocation of the power supply,television and communication facilities and the rearrangement of tubes and wires.展开更多
To evaluate the HIV pandemic in Chongqing,the pooled PCR,Ig G‐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 su...To evaluate the HIV pandemic in Chongqing,the pooled PCR,Ig G‐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).The annual acute HIV infection(AHI)incidence estimated by pooled PCR was 14.展开更多
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 th...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
Rapid urbanization in Beijing stimulates the urban land expansion and diminishes available agricultural land. Monofunctional agricultural land use can not meet the demand of the devel- opment of the multifunctional ag...Rapid urbanization in Beijing stimulates the urban land expansion and diminishes available agricultural land. Monofunctional agricultural land use can not meet the demand of the devel- opment of the multifunctional agriculture and urbanization any more, so multifunctional agricultural land use is going to be promoted in the city. This article proposes the evolvement of the land use change from 1992 to 2004 and discusses some evolvement views.展开更多
Fatal traffic accidents in urban areas can adversely affect the urban road traffic system and pose many challenges for urban traffic management.Therefore,it is necessary to first classify emergency responses to such a...Fatal traffic accidents in urban areas can adversely affect the urban road traffic system and pose many challenges for urban traffic management.Therefore,it is necessary to first classify emergency responses to such accidents and then handle them quickly and correctly.The aim of this paper is to develop an evaluation index system and to use appropriate methods to investigate emergency-response classifications to fatal traffic accidents in Chinese urban areas.This study used a multilevel hierarchical structural model to determine emergency-response classification.In the model,accident attributes,urban road network vulnerability,and institutional resilience were used as classification criteria.Each evaluation indicator was selected according to importance ranking and independence screening and was given an interpretation and a quantitative criterion.The Fuzzy Delphi Method was used to rank the importance of the evaluation indices and the combined weight of each index was calculated using the G1 method.Finally,the case of a fatal traffic accident was used to validate the model.The results showed that the multilevel hierarchical structural model,Fuzzy Delphi Method,and G1 method can effectively address the problem of emergency-response classification.Because of its simplicity and adaptability,the approach presented here could be useful for decisionmakers and practitioners for determining emergency-response classifications.展开更多
This paper, based on the literature review and field investigation, studied the status quo of maker spaces in main urban district of Chengdu at a time when the development of the maker spaces has received strong suppo...This paper, based on the literature review and field investigation, studied the status quo of maker spaces in main urban district of Chengdu at a time when the development of the maker spaces has received strong support from national and local governments. In addition to introducing the related concepts and policy support of the maker space, it summarized its distribution characteristics, audience characteristics, and status quo as well as problems and presented the direction for the development of the maker space in main urban area of Chengdu grounded on a survey of the status quo of national maker spaces in main urban area of Chengdu.展开更多
Sponge city construction,as an important measure of ecological construction in China,can effectively solve a series of problems such as large annual runoff,serious non-point source pollution,regional water shortage,lo...Sponge city construction,as an important measure of ecological construction in China,can effectively solve a series of problems such as large annual runoff,serious non-point source pollution,regional water shortage,low utilization rate of rain and flood resources,unsustainable ecological benefits of water landscape and poor landscape functions in urbanization construction. This paper uses LID concept to construct sponge city in the old urban area of Kunming,to reduce the total runoff and promote the utilization of rainfall and flood resources so as to rebuild,upgrade and optimize the regional environment and provide some reference for the regional construction of small-scale sponge city.展开更多
Under the background of"people-oriented"thought and"green transportation",the idea of"priority for non-motor vehicles"came into being,which can improve the riding environment of non-motor...Under the background of"people-oriented"thought and"green transportation",the idea of"priority for non-motor vehicles"came into being,which can improve the riding environment of non-motor vehicle riders to a certain extent.According to the current situation of priority for non-motor vehicles in the old urban area of Nanchang,through field investigation,questionnaire investigation and interview,this study summarized the existing problems,and put forward optimization suggestions for these problems,in order to provide reference for areas with similar conditions.展开更多
Through extensive access to party history materials,combined with professional knowledge,the existing red resources in Shanghai are studied from multi-dimensional,multi-level and multi-integration perspectives,to lear...Through extensive access to party history materials,combined with professional knowledge,the existing red resources in Shanghai are studied from multi-dimensional,multi-level and multi-integration perspectives,to learn party history from a new perspective.Through ArcGIS platform,the geographical distribution of red resources in Shanghai urban area is analyzed,and classification analysis,kernel density analysis and accessibility analysis are carried out according to resource types,grade of patriotism education base and grade of heritage preservation.The existing red resources in Shanghai urban area are evaluated,and the optimization suggestions are put forward.展开更多
Community walking space is the most used space in residents’daily life,such as commuting and walking,and is also the most basic type of space for outdoor activities.The microclimatic environment of walking space not ...Community walking space is the most used space in residents’daily life,such as commuting and walking,and is also the most basic type of space for outdoor activities.The microclimatic environment of walking space not only affects the health status of residents,but also determines the service effi ciency of outdoor public space.Based on actual measurement and simulation of microclimatic environment,the status quo of walkability of microclimatic environments in six typical communities is evaluated by quantitative methods,and general problems and optimization suggestions are put forward,in order to provide new ideas for future community environment transformation.展开更多
As one of the methods of urban environmental assessment,sensitivity assessment of urban climatic environment can accurately reflect the problem areas of current urban climate and built environment through visual means...As one of the methods of urban environmental assessment,sensitivity assessment of urban climatic environment can accurately reflect the problem areas of current urban climate and built environment through visual means,and help cities to carry out sustainable transformation and renewal in the stock era to optimize the living environment.Taking the central urban area of Beijing as the research object,the sensitivity of climatic environment was evaluated by meteorological data and built environment element data.The results showed that the distribution of sensitive units showed a centrifugal radiation pattern of"high in the center and low in the periphery".Block units with high climate sensitivity were mostly concentrated in Xicheng District and Dongcheng District,accounting for 93%of the total number of units.Further research showed that complex built environment and lack of elements to regulate climatic environment were the main reasons for the poor local climatic environment in the region with high climate sensitivity.Finally,a comprehensive evaluation of the remolding capacity,renewal potential and future development intensity of different grades of climate sensitive units was given.The results will provide scientific reference for urban renewal and reconstruction under climatic and environmental changes,so as to promote urban sustainable development and improvement of living environment.展开更多
Interference control can be realized by selecting the antenna’ s electrical and engineering parameters such as gain and radiation pattern, height, azimuth and downtilt to directly influence the field intensity distri...Interference control can be realized by selecting the antenna’ s electrical and engineering parameters such as gain and radiation pattern, height, azimuth and downtilt to directly influence the field intensity distribution of radio signals and effectively and reasonably distribute the electro-magnetic energy. This paper discusses how to select an antenna for a densely populated urban area. The discussion is based on the simulation platform of ZTE ’ s WCDMA planning system.展开更多
This paper presents a global methodology to compute wind flow in complex urban areas in order to assess wind pedestrian comfort, wind energy, wind safety or natural ventilation potential. The numerical tool presented ...This paper presents a global methodology to compute wind flow in complex urban areas in order to assess wind pedestrian comfort, wind energy, wind safety or natural ventilation potential. The numerical tool presented here is composed of a CFD soft-ware suite covering both regional scale (20 km) and urban scale (1km), and able to model the wind in any complex terrains and in large urban environments. Examples are presented in the paper in order to show the advantages of the methodology for urban designers.展开更多
From 2007 to 2017 sixty-three (63) new cases of human rabies have been identified in Mali on an estimated total population in 2017 of 17,650,195 inhabitants. This is an incidence of 0.32 cases for 100,000 inhabitants....From 2007 to 2017 sixty-three (63) new cases of human rabies have been identified in Mali on an estimated total population in 2017 of 17,650,195 inhabitants. This is an incidence of 0.32 cases for 100,000 inhabitants. All these cases occurred in urban areas and involved the two sexes. The age group most affected was the one less than 20 years old. The majority of the victims (73.1%) were pre-schools, school-aged pupils and housewives. In 97% of the cases, the animal in question was a dog and the type of exposure of the bite. Eighty-two percent (82%) of the victims had received no local medical treatment or the post exposure quasi prophylaxis treatment. The median duration between the first symptoms and death among the cases of human rabies was 3 to 7 days. The median duration between the occurrence of the first signs and death was four (4) days. No virological confirmation had been conducted on the patients. The rage disease is retained as a priority disease, since the adoption of the strategy of “integrated monitoring of the disease and response” in 2008. However, in spite of the efforts made, progress still remains to be effected to assess the actual impact of rabies in Mali.展开更多
China is witnessing a very complicated economic development environment.Migrant workers'working patterns will directly affect their income level and the realization of many economic and social development goals.Th...China is witnessing a very complicated economic development environment.Migrant workers'working patterns will directly affect their income level and the realization of many economic and social development goals.This paper collects relevant data from three places:Shanghai,Lanzhou and Chengdu for empirical research whose results show that determinants of migrant worker's willing working time in urban areas mainly include the“income-consumption difference”,“urban-rural consumption difference”and their“urban income and expenditure uncertainty”.These factors directly affect their effective working time in the city,and determine their choice of choosing corresponding work patterns.From the significant differences of these factors,we can see that migrant workers in China is still struggling to solve their material needs under the pressure of livelihood,and less attention is paid to their spiritual needs and the pursuit of quality of life.展开更多
In industry-oriented peri-urban areas, the heavy metal accumulation in soils caused by industrialization has become a potential threat. The top soil samples from 27 paddy fields and 75 vegetable fields were collected ...In industry-oriented peri-urban areas, the heavy metal accumulation in soils caused by industrialization has become a potential threat. The top soil samples from 27 paddy fields and 75 vegetable fields were collected from a typical industry-based peri-urban area of about 8 km2 in Wuxi, China, to study the accumulation and distribution of As, Hg, Cu, Zn, Pb, Cr, and Cd in comparison with heavy metal contents in soils near developed industrial sites (Guangzhou, China; Wallsend Burn of Tyneside, UK; and Osnabriick, Germany). Kriging interpolation was used to determine the metals' spatial distribution. The results showed that most soils, compared to the background values, contained elevated contents of As, Hg, Cu, Zn, and Pb with some having elevated contents of Cd and Cr. Except for less than 10% of the soil samples of Cu, Zn and Cd contents, these heavy metal contents were lower than the soil threshold levels of the Grade II criteria for the Chinese environmental quality standard. Probably, because of the scattered distribution and diversity of industries in the study area, spatial distributions of these heavy metals from Kriging interpolation indicated little similarity. Nevertheless, when compared with other areas in the Taihu Lake region, mean contents of Cu, Zn, Pb, and Cd were relatively high in the Wuxi peri-urban area. Additionally, compared to soils in agricultural areas around Guangzhou, Osnabriick, or Wallsend Burn, contents of most heavy metals in soils from this area were lower.展开更多
基金financial supports for this research project by the National Natural Science Foundation of China(Nos.41602308,41967037)supported by Zhejiang Provincial Natural Science Foundation of China under Grant No.LY20E080005+1 种基金funded by National Key Research and Development Projects of China(No.2019YFC507502)Guangxi Science and Technology Plan Project(No.RZ2100000161).
文摘During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is located.The monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction areas.The former is the gathering point of the entire urban population.There are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation cover.Several existing items requiremonitoring.However,monitoring distance is long,and providing early warning is difficult.This study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence deformation.Then,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway operation.Results show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 mm.And FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation.
文摘Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Project,research on HSR route selection in complicated urban areas has been conducted.An optimal route selection plan is determined after studying the local geological and environmental conditions and the complexity of tunnel construction.The research concludes that there are four major concerns in HSR route selection:the match between the new route and the urban planning,the potential economic return for the massive investment,the likely impacts of land expropriation on social stability,and the best synthesis of multiple controlling factors to meet the HSR standard.Moreover,six principles should be followed in railway route selection in complicated urban areas:the new route should be in alignment with the railway deployment;the route should align with the existing passage as much as possible;extensive analysis and in-depth demonstrations should be done to find the most appropriate combination of open and hidden excavation in tunnel construction;geological conditions and tunnel construction complexities are among the priorities;environmental sensitive sites and environmental vibration noise should be avoided as much as possible;special attention should be paid to the relocation of the power supply,television and communication facilities and the rearrangement of tubes and wires.
基金supported by the Department of Health and Family Counseling,Chongqing[2016HBRC009,2017ZDXM001]
文摘To evaluate the HIV pandemic in Chongqing,the pooled PCR,Ig G‐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).The annual acute HIV infection(AHI)incidence estimated by pooled PCR was 14.
基金Supported by the Major Research Plan of the National Natural Science Foundation of China(91120003)Surface Project of the National Natural Science Foundation of China(61173076)
文摘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.
基金National Nature Science Foundation of China (Grant No. 40571056).
文摘Rapid urbanization in Beijing stimulates the urban land expansion and diminishes available agricultural land. Monofunctional agricultural land use can not meet the demand of the devel- opment of the multifunctional agriculture and urbanization any more, so multifunctional agricultural land use is going to be promoted in the city. This article proposes the evolvement of the land use change from 1992 to 2004 and discusses some evolvement views.
基金supported by the Fifth 333 High-Level Talents Project of Jiangsu Province under Grant BRA2017443the Key Research Base of Jiangsu University Philosophy and Social Science under Grant 2018ZDJD-B007.
文摘Fatal traffic accidents in urban areas can adversely affect the urban road traffic system and pose many challenges for urban traffic management.Therefore,it is necessary to first classify emergency responses to such accidents and then handle them quickly and correctly.The aim of this paper is to develop an evaluation index system and to use appropriate methods to investigate emergency-response classifications to fatal traffic accidents in Chinese urban areas.This study used a multilevel hierarchical structural model to determine emergency-response classification.In the model,accident attributes,urban road network vulnerability,and institutional resilience were used as classification criteria.Each evaluation indicator was selected according to importance ranking and independence screening and was given an interpretation and a quantitative criterion.The Fuzzy Delphi Method was used to rank the importance of the evaluation indices and the combined weight of each index was calculated using the G1 method.Finally,the case of a fatal traffic accident was used to validate the model.The results showed that the multilevel hierarchical structural model,Fuzzy Delphi Method,and G1 method can effectively address the problem of emergency-response classification.Because of its simplicity and adaptability,the approach presented here could be useful for decisionmakers and practitioners for determining emergency-response classifications.
基金Sponsored by National Natural Science Fund(51508471)Philosophy and Social Science Project of Sichuan Province(MD16E017)+2 种基金Soft Science Project of Chengdu City(2015-RK00-00270-ZF)Operating Costs of Innovation Project of Science and Engineering in Colleges and Universities Administrated by Ministries and Their Attached Institutions in 2017(2682017CX016)Teaching Research and Reform Project for Undergraduate Education of Southwest Jiaotong University in 2017(201704048)
文摘This paper, based on the literature review and field investigation, studied the status quo of maker spaces in main urban district of Chengdu at a time when the development of the maker spaces has received strong support from national and local governments. In addition to introducing the related concepts and policy support of the maker space, it summarized its distribution characteristics, audience characteristics, and status quo as well as problems and presented the direction for the development of the maker space in main urban area of Chengdu grounded on a survey of the status quo of national maker spaces in main urban area of Chengdu.
基金Supported by Science Research Fund of Yunnan Provincial Department of Education(2017ZZX090)Key Scientific Research Project of University(XJZD1602)Open Fund Project of Key Laboratories for the Opening and Utilization of Characteristic Biological Resources in Colleges and Universities of Yunnan Province,Kunming University(GXKZ201714)
文摘Sponge city construction,as an important measure of ecological construction in China,can effectively solve a series of problems such as large annual runoff,serious non-point source pollution,regional water shortage,low utilization rate of rain and flood resources,unsustainable ecological benefits of water landscape and poor landscape functions in urbanization construction. This paper uses LID concept to construct sponge city in the old urban area of Kunming,to reduce the total runoff and promote the utilization of rainfall and flood resources so as to rebuild,upgrade and optimize the regional environment and provide some reference for the regional construction of small-scale sponge city.
文摘Under the background of"people-oriented"thought and"green transportation",the idea of"priority for non-motor vehicles"came into being,which can improve the riding environment of non-motor vehicle riders to a certain extent.According to the current situation of priority for non-motor vehicles in the old urban area of Nanchang,through field investigation,questionnaire investigation and interview,this study summarized the existing problems,and put forward optimization suggestions for these problems,in order to provide reference for areas with similar conditions.
基金Sponsored by General Project of Natural Science Foundation of Beijing City(8202017)2018 Beijing Municipal University Academic Human Resources Development-Youth Talent Support Program(PXM2018_014212_000043)。
文摘Through extensive access to party history materials,combined with professional knowledge,the existing red resources in Shanghai are studied from multi-dimensional,multi-level and multi-integration perspectives,to learn party history from a new perspective.Through ArcGIS platform,the geographical distribution of red resources in Shanghai urban area is analyzed,and classification analysis,kernel density analysis and accessibility analysis are carried out according to resource types,grade of patriotism education base and grade of heritage preservation.The existing red resources in Shanghai urban area are evaluated,and the optimization suggestions are put forward.
基金Beijing Natural Science Foundation(8202017)2018 Beijing Municipal University Academic Human Resources Development—Youth Talent Support Program(PXM2018212-000043)National Natural Science Foundation of China(31570699).
文摘Community walking space is the most used space in residents’daily life,such as commuting and walking,and is also the most basic type of space for outdoor activities.The microclimatic environment of walking space not only affects the health status of residents,but also determines the service effi ciency of outdoor public space.Based on actual measurement and simulation of microclimatic environment,the status quo of walkability of microclimatic environments in six typical communities is evaluated by quantitative methods,and general problems and optimization suggestions are put forward,in order to provide new ideas for future community environment transformation.
基金Sponsored by General Project of Natural Science Foundation of Beijing City(8202017)Youth Talent Support Program of 2018 Beijing Municipal University Academic Human Resources Development(PXM2018_014212_000043)。
文摘As one of the methods of urban environmental assessment,sensitivity assessment of urban climatic environment can accurately reflect the problem areas of current urban climate and built environment through visual means,and help cities to carry out sustainable transformation and renewal in the stock era to optimize the living environment.Taking the central urban area of Beijing as the research object,the sensitivity of climatic environment was evaluated by meteorological data and built environment element data.The results showed that the distribution of sensitive units showed a centrifugal radiation pattern of"high in the center and low in the periphery".Block units with high climate sensitivity were mostly concentrated in Xicheng District and Dongcheng District,accounting for 93%of the total number of units.Further research showed that complex built environment and lack of elements to regulate climatic environment were the main reasons for the poor local climatic environment in the region with high climate sensitivity.Finally,a comprehensive evaluation of the remolding capacity,renewal potential and future development intensity of different grades of climate sensitive units was given.The results will provide scientific reference for urban renewal and reconstruction under climatic and environmental changes,so as to promote urban sustainable development and improvement of living environment.
文摘Interference control can be realized by selecting the antenna’ s electrical and engineering parameters such as gain and radiation pattern, height, azimuth and downtilt to directly influence the field intensity distribution of radio signals and effectively and reasonably distribute the electro-magnetic energy. This paper discusses how to select an antenna for a densely populated urban area. The discussion is based on the simulation platform of ZTE ’ s WCDMA planning system.
文摘This paper presents a global methodology to compute wind flow in complex urban areas in order to assess wind pedestrian comfort, wind energy, wind safety or natural ventilation potential. The numerical tool presented here is composed of a CFD soft-ware suite covering both regional scale (20 km) and urban scale (1km), and able to model the wind in any complex terrains and in large urban environments. Examples are presented in the paper in order to show the advantages of the methodology for urban designers.
文摘From 2007 to 2017 sixty-three (63) new cases of human rabies have been identified in Mali on an estimated total population in 2017 of 17,650,195 inhabitants. This is an incidence of 0.32 cases for 100,000 inhabitants. All these cases occurred in urban areas and involved the two sexes. The age group most affected was the one less than 20 years old. The majority of the victims (73.1%) were pre-schools, school-aged pupils and housewives. In 97% of the cases, the animal in question was a dog and the type of exposure of the bite. Eighty-two percent (82%) of the victims had received no local medical treatment or the post exposure quasi prophylaxis treatment. The median duration between the first symptoms and death among the cases of human rabies was 3 to 7 days. The median duration between the occurrence of the first signs and death was four (4) days. No virological confirmation had been conducted on the patients. The rage disease is retained as a priority disease, since the adoption of the strategy of “integrated monitoring of the disease and response” in 2008. However, in spite of the efforts made, progress still remains to be effected to assess the actual impact of rabies in Mali.
基金The National Social Science Fund of China:Study on the Impact of Migrant Workers'Migrant Birds Work Mode and Employment Security in the Process of Urbanization(15XJL011)。
文摘China is witnessing a very complicated economic development environment.Migrant workers'working patterns will directly affect their income level and the realization of many economic and social development goals.This paper collects relevant data from three places:Shanghai,Lanzhou and Chengdu for empirical research whose results show that determinants of migrant worker's willing working time in urban areas mainly include the“income-consumption difference”,“urban-rural consumption difference”and their“urban income and expenditure uncertainty”.These factors directly affect their effective working time in the city,and determine their choice of choosing corresponding work patterns.From the significant differences of these factors,we can see that migrant workers in China is still struggling to solve their material needs under the pressure of livelihood,and less attention is paid to their spiritual needs and the pursuit of quality of life.
基金Project supported by the RURBIFARM (Sustainable Farming at the Rural-Urban Interface) project of the European Union (No. ICA4-CT-2002-10021)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX3-SW-427)the National Key Basic Research Support Foundation of China (No. 2002CB410810).
文摘In industry-oriented peri-urban areas, the heavy metal accumulation in soils caused by industrialization has become a potential threat. The top soil samples from 27 paddy fields and 75 vegetable fields were collected from a typical industry-based peri-urban area of about 8 km2 in Wuxi, China, to study the accumulation and distribution of As, Hg, Cu, Zn, Pb, Cr, and Cd in comparison with heavy metal contents in soils near developed industrial sites (Guangzhou, China; Wallsend Burn of Tyneside, UK; and Osnabriick, Germany). Kriging interpolation was used to determine the metals' spatial distribution. The results showed that most soils, compared to the background values, contained elevated contents of As, Hg, Cu, Zn, and Pb with some having elevated contents of Cd and Cr. Except for less than 10% of the soil samples of Cu, Zn and Cd contents, these heavy metal contents were lower than the soil threshold levels of the Grade II criteria for the Chinese environmental quality standard. Probably, because of the scattered distribution and diversity of industries in the study area, spatial distributions of these heavy metals from Kriging interpolation indicated little similarity. Nevertheless, when compared with other areas in the Taihu Lake region, mean contents of Cu, Zn, Pb, and Cd were relatively high in the Wuxi peri-urban area. Additionally, compared to soils in agricultural areas around Guangzhou, Osnabriick, or Wallsend Burn, contents of most heavy metals in soils from this area were lower.
