The present analysis provided the quality assessment of 65 Continuous Operating Reference Stations(CORS) situated in and around Mexico using the data of about ten years(January 2010 to January 2020).To accomplish the ...The present analysis provided the quality assessment of 65 Continuous Operating Reference Stations(CORS) situated in and around Mexico using the data of about ten years(January 2010 to January 2020).To accomplish the assessment,we considered 4 quality indexes for performing the quality check,incluing the multipath effect on L1 and L2 bands,signal-to-noise ratio in both bands,cycle slips,and integrity.Meanwhile,a new reference parameter named regio nal values for Mexico(RVM) was calculated for the stations situated in Mexico.Additionally,an exhaustive analysis of the quality indicators in the worst and best cases was performed.The signal degradation was proved by a long-term time series and cru stal defo rmation analysis in GAMIT/GLOBK platform.The results showed a stro ng correlation between integrity,cycle slips and daily observations time,and the multipath effect is strong in the case of outdated systems.The study indicates that the estimated quality indexes and values could be the basis for establishing new CORS in Mexico,and the errors corrections which cannot be mitigated in the postprocessing stage would greatly help utilize the data for different scientific applications.The results were supported by deformation analysis in part of Baja California Peninsula in Mexico indicating northern and eastern velocity vector of -3.08±0.02 mm/yr,-7.85±0.02 mm/yr and-0.07±0.03 mm/yr,-9.33±0.02 mm/yr respectively at MPR1 and INEG stations.展开更多
The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major ...The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major cotton production provinces between 2001 to 2005 were analyzed.Eight quality展开更多
Acceptance sampling is a well-established statistical technique in quality assurance.Acceptance sampling is used to decide,acceptance or rejection of a lot based on the inspection of its random sample.Experts concur t...Acceptance sampling is a well-established statistical technique in quality assurance.Acceptance sampling is used to decide,acceptance or rejection of a lot based on the inspection of its random sample.Experts concur that the Bayesian approach is the best approach to make a correct decision,when historical knowledge is available.This paper suggests a Bayesian new group chain sampling plan(BNGChSP)to estimate average probability of acceptance.Binomial distribution function is used to differentiate between defective and non-defective products.Beta distribution is considered as a suitable prior distribution.Derivation is completed for the estimation of the average proportion of defectives.This study includes four quality regions namely:(i)probabilistic quality region(PQR),(ii)quality decision region(QDR),(iii)limiting quality region(LQR),and(iv)indifference quality region(IQR).The estimated values for the BNGChSPare tabulated and the inflection point values are derived,based on different combinations of design parameters including both consumer’s and producer’s risks.For comparison with the existing plan,the operating characteristic curves expose that BNGChSP is a better substitute for industrial practitioners.展开更多
According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quali...According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value.展开更多
The Weather Research and Forecasting model coupled with Chemistry(WRF-Chem),a type of online coupled chemistry-meteorology model(CCMM),considers the interaction between air quality and meteorology to improve air quali...The Weather Research and Forecasting model coupled with Chemistry(WRF-Chem),a type of online coupled chemistry-meteorology model(CCMM),considers the interaction between air quality and meteorology to improve air quality forecasting.Meteorological data assimilation(DA)can be used to reduce uncertainty in meteorological field,which is one factor causing prediction uncertainty in the CCMM.In this study,WRF-Chem and three-dimensional variational DA were used to examine the impact of meteorological DA on air quality and meteorological forecasts over the Korean Peninsula.The nesting model domains were configured over East Asia(outer domain)and the Korean Peninsula(inner domain).Three experiments were conducted by using different DA domains to determine the optimal model domain for the meteorological DA.When the meteorological DA was performed in the outer domain or both the outer and inner domains,the root-mean-square error(RMSE),bias of the predicted particulate matter(PM)concentrations,and the RMSE of predicted meteorological variables against the observations were smaller than those in the experiment where the meteorological DA was performed only in the inner domain.This indicates that the improvement of the synoptic meteorological fields by DA in the outer domain enhanced the meteorological initial and boundary conditions for the inner domain,subsequently improving air quality and meteorological predictions.Compared to the experiment without meteorological DA,the RMSE and bias of the meteorological and PM variables were smaller in the experiments with DA.The effect of meteorological DA on the improvement of PM predictions lasted for approximately 58-66 h,depending on the case.Therefore,the uncertainty reduction in the meteorological initial condition by the meteorological DA contributed to a reduction of the forecast errors of both meteorology and air quality.展开更多
Phosphorus(P) losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice(O...Phosphorus(P) losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice(Oryza sativa L.) and wheat(Triticum aestivum L.) cropping systems in Lake Taihu region, China. The study was conducted on two types of paddy soils(Hydromorphic at Anzhen site, Wuxi City, and Degleyed at Xinzhuang site, Changshu City, Jiangsu Province) with different P status, and it covered 3 years with low, high and normal rainfall regimes. Four rates of mineral P fertilizer, i.e., no P(control), 30 kg P ha^(–1) for rice and 20 kg P ha^(–1) for wheat(P_(30+20)), 75 plus 40(P_(75+40)), and 150 plus 80(P_(150+80)), were applied as treatments. Runoff water from individual plots and runoff events was recorded and analyzed for total P and dissolved reactive P concentrations. Losses of total P and dissolved reactive P significantly increased with rainfall depth and P rates(P〈0.0001). Annual total P losses ranged from 0.36–0.92 kg ha^–1 in control to 1.13–4.67 kg ha^–1 in P150+80 at Anzhen, and correspondingly from 0.36–0.48 kg h^–1 to 1.26–1.88 kg ha^–1 at Xinzhuang, with 16–49% of total P as dissolved reactive P. In particular, large amounts of P were lost during heavy rainfall events that occurred shortly after P applications at Anzhen. On average of all P treatments, rice growing season constituted 37–86% of annual total P loss at Anzhen and 28–44% of that at Xinzhuang. In both crop seasons, P concentrations peaked in the first runoff events and decreased with time. During rice growing season, runoff P concentrations positively correlated(P〈0.0001) with P concentrations in field ponding water that was intentionally enclosed by construction of field bund. The relative high P loss during wheat growing season at Xinzhuang was due to high soil P status. In conclusion, P should be applied at rates balancing crop removal(20–30 kg P ha^–1 in this study) and at time excluding heavy rains. Moreover, irrigation and drainage water should be appropriately managed to reduce runoff P losses from rice-wheat cropping systems.展开更多
Study of Air Quality Objectives(AQOs)and long-term changes of air pollution plays a decisive role in formulating and refining pollution control strategies.In this study,10-year variations of six major air pollutants w...Study of Air Quality Objectives(AQOs)and long-term changes of air pollution plays a decisive role in formulating and refining pollution control strategies.In this study,10-year variations of six major air pollutants were analyzed at seven monitoring sites in Hong Kong region.The continuous decrease of annual averaged concentrations of NO_(2),SO_(2),CO,PM_(2.5)and PM_(10)and numbers of days with severe pollution conditions validated the efficiency of the series of air pollution control schemes implemented by the Hong Kong region government.However,there is still a big gap to meet the ultimate targets described by the World Health Organization.Besides,the concentration of O_(3)at roadside and urban stations increased by 135%±25%and 37%±18%from 2011 to 2020,respectively,meanwhile the highest 8 hr averaged O_(3)concentration was observed as 294μg/m^(3)at background station in 2020,which pointed out the increasing ozone pollution in Hong Kong region.There was a great decrease in the annual times of air quality health index(AQHI)laying in“high”,“very high”and“serious”categories from 2011 to 2020 with the decrease rate of 89.70%,91.30%and 89.74%at roadside stations,and 79.03%,95.98%and 72.73%at urban stations,respectively.Nevertheless,the number of days categorized as“high”or above at roadside station was twice more than that in the urban station during the past ten years.Thus,more policies and attentions should be given to the roadside air quality and its adverse health effect to pedestrians on street.展开更多
This thesis appraises the human resources in developed regions, relatively developed regions, moderately developed regions and underdeveloped regions in China by means of comprehensive fuzzy assessment of human resour...This thesis appraises the human resources in developed regions, relatively developed regions, moderately developed regions and underdeveloped regions in China by means of comprehensive fuzzy assessment of human resources quality. Then the interrelationship between regional economic development and human resources quality is analysed. The results can be of some value for decision making.展开更多
Increasing Chinese urbanization and industrialization has prompted greater attention to the study of human settlement and the human-land relationship in the fields of geography, architecture, and urban planning. We us...Increasing Chinese urbanization and industrialization has prompted greater attention to the study of human settlement and the human-land relationship in the fields of geography, architecture, and urban planning. We used bibliometric methods and statistical software to review 180 articles on human settlement in 16 Chinese geographical journals. We found that Chinese geographical human settlement research is characterized by the following:(1) Most research focuses on human settlement extension, valuation indicators, models for urban and rural settlements, theoretical exploration and the planning practices of single-factor, human settlement and complex, geographical livability in macro-scale, urban settlement differentiation and ideal patterns in medium scale, the comprehensive evaluation of settlement environment, and the planning of community units in micro-scale, community settlements; socio-cultural investigation and warnings about advancing human settlement.(2) No progress has been made in synthesizing and integrating method systems. PSR models and DPSIR models are used for targeting mechanisms, while the standard settlement evaluation system was composed of physical & economic indicators by questionnaire surveys. On the other hand, spatial clustering based on GIS has been a frequent focus in recent years. Pioneering research on human settlement and theoretical systems within the context of China's urbanization and industrialization will provide guidance on the sustainability of Chinese cities and regions. The following five aspects require greater attention:(1) Natural suitability research on human settlement, and a survey of human settlement demands to reflect the range of different demands concerning ecologically suitable settlements in urban environments, the corresponding valuation indicators, systems, and evolution, and the impact of the residents' socio-economic attributes.(2) Spatial-temporal evaluation and sustainability research on urban and rural human settlement at various scales, focusing on evolution and spatial differen-tiation at various scales such as city clusters and comparisons between cities, within the cities and communities.(3) Development of theory and technology for human settlement evolution research, including detection technology and methods, data mining measures, and forecasting and emulation of regional and urban human settlement evolution processes, mechanisms and patterns.(4) Research on the control of human settlement that focuses on optimization, patterns, and policies for effective management and development.(5) Estimating the human settlement system service value and establishing suitable human settlement systems, including social, economic, cultural and ecological service values.展开更多
A factor separation technique and an improved regional air quality model (RAQM) were applied to calculate synergistic contributions of anthropogenic volatile organic compounds (AVOCs),biogenic volatile organic com...A factor separation technique and an improved regional air quality model (RAQM) were applied to calculate synergistic contributions of anthropogenic volatile organic compounds (AVOCs),biogenic volatile organic compounds (BVOCs) and nitrogen oxides (NOx) to daily maximum surface O3(O3DM) concentrations in East Asia in summer (June to August 2000).The summer averaged synergistic impacts of AVOCs and NOx are dominant in most areas of North China,with a maximum of 60 ppbv,while those of BVOCs and NOx are notable only in some limited areas with high BVOC emissions in South China,with a maximum of 25 ppbv.This result implies that BVOCs contribute much less to summer averaged O3DM concentrations than AVOCs in most areas of East Asia at a coarse spatial resolution (1×1) although global emissions of BVOCs are much greater than those of AVOCs.Daily maximum total contributions of BVOCs can approach 20 ppbv in North China,but they can reach 40 ppbv in South China,approaching or exceeding those in some developed countries in Europe and North America.BVOC emissions in such special areas should be considered when O3 control measures are taken.Synergistic contributions among AVOCs,BVOCs and NOx significantly enhance O3 concentrations in the Beijing-Tianjin-Tangshan region and decrease them in some areas in South China.Thus,the total contributions of BVOCs to O3DM vary significantly from day to day and from location to location.This result suggests that O3 control measures obtained from episodic studies could be limited for long-term applications.展开更多
The Pearl River Delta (PRD) is one of the most industrialized, urbanized and populated regions in China, and thus has been long suffering from severe air pollutions. Space data provide a unique perspective for inves...The Pearl River Delta (PRD) is one of the most industrialized, urbanized and populated regions in China, and thus has been long suffering from severe air pollutions. Space data provide a unique perspective for investigating the atmospheric environment at a regional scale. By utilizing multiple satellite retrievals from 2005 to 2013, this study presented, for the first time, the spatial patterns and temporal trends of typical air pollutants over PRD and its vicinity. As viewed from space, aerosol optical depth (AOD), NO2 and SO2 all had their higher values at the central part of PRD, and showed clear descending gradients as moving to the outskirt of this region. As to the inter-annual variation, all these pollutants had decreasing trends in PRD during the study period, which generally agreed with the relevant in situ measurements. However, the satellite retrievals differed from ground measurements when addressing NO2 and SO2 in the vicinity of PRD. This work also provides the inter-comparison among PRD and three other metropolitan clusters in China: PRD had relatively high AOD, moderate NO2 and low SO2 levels, and it was the only region achieving the effective reduction of NO2 and SO2 during last decade. Unlike the previous three pollutants, HCHO observed by satellite showed very special patterns: it had a relatively homogeneous spatial distribution over both of PRD and its vicinity, and presented an opposite increasing trend from 2005 to 2010. Moreover, PRD had the highest HCHO level among all the metropolitan clusters, hinting a considerable contribution of biogenic origins of HCHO in PRD.展开更多
For the years 2008-2013, particles of diameter 〈 10 and 2.5 μm (PM10 and PM2.5, respectively), NOx, SO2, and O3 concentrations at urban, suburban, rural, and traffic sites in the Paris metropolitan area were analy...For the years 2008-2013, particles of diameter 〈 10 and 2.5 μm (PM10 and PM2.5, respectively), NOx, SO2, and O3 concentrations at urban, suburban, rural, and traffic sites in the Paris metropolitan area were analyzed. Strong spatial variability at traffic and rural sites and relatively uniform profiles at urban and suburban sites for PM10, PM2.5, and O3 were observed. The O3 weekend effect was induced by lower NOx emissions during the weekend, and favored volatile organic compounds (VOCs)-limited atmospheric conditions. In conJunction with low ambient temperature, these conditions could also favor increased formation of secondary particulate nitrates in winter. Winter air pollution events were associated with multiple pollutants, whereas those observed in spring were caused by high PM10 and PM2.5 levels. Back- ward trajectory analyses showed the contribution of sources in Western and Central Europe on days with high PM10, PM2.5, and O3, and a local/national comvonent for NOx and SO2.展开更多
基金data provided by the GAGE Facility, operated by UNAVCO, Inc., with support from the National Science Foundation and the National Aeronautics and Space Administration under NSF Cooperative Agreement EAR-1724794。
文摘The present analysis provided the quality assessment of 65 Continuous Operating Reference Stations(CORS) situated in and around Mexico using the data of about ten years(January 2010 to January 2020).To accomplish the assessment,we considered 4 quality indexes for performing the quality check,incluing the multipath effect on L1 and L2 bands,signal-to-noise ratio in both bands,cycle slips,and integrity.Meanwhile,a new reference parameter named regio nal values for Mexico(RVM) was calculated for the stations situated in Mexico.Additionally,an exhaustive analysis of the quality indicators in the worst and best cases was performed.The signal degradation was proved by a long-term time series and cru stal defo rmation analysis in GAMIT/GLOBK platform.The results showed a stro ng correlation between integrity,cycle slips and daily observations time,and the multipath effect is strong in the case of outdated systems.The study indicates that the estimated quality indexes and values could be the basis for establishing new CORS in Mexico,and the errors corrections which cannot be mitigated in the postprocessing stage would greatly help utilize the data for different scientific applications.The results were supported by deformation analysis in part of Baja California Peninsula in Mexico indicating northern and eastern velocity vector of -3.08±0.02 mm/yr,-7.85±0.02 mm/yr and-0.07±0.03 mm/yr,-9.33±0.02 mm/yr respectively at MPR1 and INEG stations.
文摘The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major cotton production provinces between 2001 to 2005 were analyzed.Eight quality
基金This research was supported by the Ministry of Education(MOE)through Fundamental Research Grant Scheme(FRGS/1/2020/STG06/UUM/02/2),S/O Code 14884.
文摘Acceptance sampling is a well-established statistical technique in quality assurance.Acceptance sampling is used to decide,acceptance or rejection of a lot based on the inspection of its random sample.Experts concur that the Bayesian approach is the best approach to make a correct decision,when historical knowledge is available.This paper suggests a Bayesian new group chain sampling plan(BNGChSP)to estimate average probability of acceptance.Binomial distribution function is used to differentiate between defective and non-defective products.Beta distribution is considered as a suitable prior distribution.Derivation is completed for the estimation of the average proportion of defectives.This study includes four quality regions namely:(i)probabilistic quality region(PQR),(ii)quality decision region(QDR),(iii)limiting quality region(LQR),and(iv)indifference quality region(IQR).The estimated values for the BNGChSPare tabulated and the inflection point values are derived,based on different combinations of design parameters including both consumer’s and producer’s risks.For comparison with the existing plan,the operating characteristic curves expose that BNGChSP is a better substitute for industrial practitioners.
基金Supported by Basic Scientific Research Project of Henan Academy of Sciences(200601078)Henan Youth Science(212300410168)Henan Science and Technology Plan Project (212400410263)。
文摘According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value.
基金Supported by the National Research Foundation of Korea(2021R1A2C1012572)funded by the South Korean government(Ministry of Science and ICT)Yonsei Signature Research Cluster Program of 2023(2023-22-0009)National Institute of Environmental Research(NIER-2022-01-02-076)funded by the Ministry of Environment(MOE)of the Republic of Korea。
文摘The Weather Research and Forecasting model coupled with Chemistry(WRF-Chem),a type of online coupled chemistry-meteorology model(CCMM),considers the interaction between air quality and meteorology to improve air quality forecasting.Meteorological data assimilation(DA)can be used to reduce uncertainty in meteorological field,which is one factor causing prediction uncertainty in the CCMM.In this study,WRF-Chem and three-dimensional variational DA were used to examine the impact of meteorological DA on air quality and meteorological forecasts over the Korean Peninsula.The nesting model domains were configured over East Asia(outer domain)and the Korean Peninsula(inner domain).Three experiments were conducted by using different DA domains to determine the optimal model domain for the meteorological DA.When the meteorological DA was performed in the outer domain or both the outer and inner domains,the root-mean-square error(RMSE),bias of the predicted particulate matter(PM)concentrations,and the RMSE of predicted meteorological variables against the observations were smaller than those in the experiment where the meteorological DA was performed only in the inner domain.This indicates that the improvement of the synoptic meteorological fields by DA in the outer domain enhanced the meteorological initial and boundary conditions for the inner domain,subsequently improving air quality and meteorological predictions.Compared to the experiment without meteorological DA,the RMSE and bias of the meteorological and PM variables were smaller in the experiments with DA.The effect of meteorological DA on the improvement of PM predictions lasted for approximately 58-66 h,depending on the case.Therefore,the uncertainty reduction in the meteorological initial condition by the meteorological DA contributed to a reduction of the forecast errors of both meteorology and air quality.
基金funded by the Special Fund for AgroScientific Research in the Public Interest, China (201003014)
文摘Phosphorus(P) losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice(Oryza sativa L.) and wheat(Triticum aestivum L.) cropping systems in Lake Taihu region, China. The study was conducted on two types of paddy soils(Hydromorphic at Anzhen site, Wuxi City, and Degleyed at Xinzhuang site, Changshu City, Jiangsu Province) with different P status, and it covered 3 years with low, high and normal rainfall regimes. Four rates of mineral P fertilizer, i.e., no P(control), 30 kg P ha^(–1) for rice and 20 kg P ha^(–1) for wheat(P_(30+20)), 75 plus 40(P_(75+40)), and 150 plus 80(P_(150+80)), were applied as treatments. Runoff water from individual plots and runoff events was recorded and analyzed for total P and dissolved reactive P concentrations. Losses of total P and dissolved reactive P significantly increased with rainfall depth and P rates(P〈0.0001). Annual total P losses ranged from 0.36–0.92 kg ha^–1 in control to 1.13–4.67 kg ha^–1 in P150+80 at Anzhen, and correspondingly from 0.36–0.48 kg h^–1 to 1.26–1.88 kg ha^–1 at Xinzhuang, with 16–49% of total P as dissolved reactive P. In particular, large amounts of P were lost during heavy rainfall events that occurred shortly after P applications at Anzhen. On average of all P treatments, rice growing season constituted 37–86% of annual total P loss at Anzhen and 28–44% of that at Xinzhuang. In both crop seasons, P concentrations peaked in the first runoff events and decreased with time. During rice growing season, runoff P concentrations positively correlated(P〈0.0001) with P concentrations in field ponding water that was intentionally enclosed by construction of field bund. The relative high P loss during wheat growing season at Xinzhuang was due to high soil P status. In conclusion, P should be applied at rates balancing crop removal(20–30 kg P ha^–1 in this study) and at time excluding heavy rains. Moreover, irrigation and drainage water should be appropriately managed to reduce runoff P losses from rice-wheat cropping systems.
基金supported by the Research Grants Council of Hong Kong Government(Project No.T24/504/17 and T31-603/21-N)he Environment and Conservation Fund of Hong Kong Governmentt(Project No.ECF 63/2019).
文摘Study of Air Quality Objectives(AQOs)and long-term changes of air pollution plays a decisive role in formulating and refining pollution control strategies.In this study,10-year variations of six major air pollutants were analyzed at seven monitoring sites in Hong Kong region.The continuous decrease of annual averaged concentrations of NO_(2),SO_(2),CO,PM_(2.5)and PM_(10)and numbers of days with severe pollution conditions validated the efficiency of the series of air pollution control schemes implemented by the Hong Kong region government.However,there is still a big gap to meet the ultimate targets described by the World Health Organization.Besides,the concentration of O_(3)at roadside and urban stations increased by 135%±25%and 37%±18%from 2011 to 2020,respectively,meanwhile the highest 8 hr averaged O_(3)concentration was observed as 294μg/m^(3)at background station in 2020,which pointed out the increasing ozone pollution in Hong Kong region.There was a great decrease in the annual times of air quality health index(AQHI)laying in“high”,“very high”and“serious”categories from 2011 to 2020 with the decrease rate of 89.70%,91.30%and 89.74%at roadside stations,and 79.03%,95.98%and 72.73%at urban stations,respectively.Nevertheless,the number of days categorized as“high”or above at roadside station was twice more than that in the urban station during the past ten years.Thus,more policies and attentions should be given to the roadside air quality and its adverse health effect to pedestrians on street.
基金This paper is funded by National Science Fund. No:79770 0 81
文摘This thesis appraises the human resources in developed regions, relatively developed regions, moderately developed regions and underdeveloped regions in China by means of comprehensive fuzzy assessment of human resources quality. Then the interrelationship between regional economic development and human resources quality is analysed. The results can be of some value for decision making.
基金National Natural Science Foundation of China,No.41230632,No.41301110,No.41501119 Zhejiang Provincial Natural Science Foundation of China,No.LY16D010008,No.Y14D010007
文摘Increasing Chinese urbanization and industrialization has prompted greater attention to the study of human settlement and the human-land relationship in the fields of geography, architecture, and urban planning. We used bibliometric methods and statistical software to review 180 articles on human settlement in 16 Chinese geographical journals. We found that Chinese geographical human settlement research is characterized by the following:(1) Most research focuses on human settlement extension, valuation indicators, models for urban and rural settlements, theoretical exploration and the planning practices of single-factor, human settlement and complex, geographical livability in macro-scale, urban settlement differentiation and ideal patterns in medium scale, the comprehensive evaluation of settlement environment, and the planning of community units in micro-scale, community settlements; socio-cultural investigation and warnings about advancing human settlement.(2) No progress has been made in synthesizing and integrating method systems. PSR models and DPSIR models are used for targeting mechanisms, while the standard settlement evaluation system was composed of physical & economic indicators by questionnaire surveys. On the other hand, spatial clustering based on GIS has been a frequent focus in recent years. Pioneering research on human settlement and theoretical systems within the context of China's urbanization and industrialization will provide guidance on the sustainability of Chinese cities and regions. The following five aspects require greater attention:(1) Natural suitability research on human settlement, and a survey of human settlement demands to reflect the range of different demands concerning ecologically suitable settlements in urban environments, the corresponding valuation indicators, systems, and evolution, and the impact of the residents' socio-economic attributes.(2) Spatial-temporal evaluation and sustainability research on urban and rural human settlement at various scales, focusing on evolution and spatial differen-tiation at various scales such as city clusters and comparisons between cities, within the cities and communities.(3) Development of theory and technology for human settlement evolution research, including detection technology and methods, data mining measures, and forecasting and emulation of regional and urban human settlement evolution processes, mechanisms and patterns.(4) Research on the control of human settlement that focuses on optimization, patterns, and policies for effective management and development.(5) Estimating the human settlement system service value and establishing suitable human settlement systems, including social, economic, cultural and ecological service values.
基金supported by the National Natural Science Foundation of China(No.40905055,41175105)the Key Project of the Chinese Academy of Sciences(No.KZCX1-YW-06-04)
文摘A factor separation technique and an improved regional air quality model (RAQM) were applied to calculate synergistic contributions of anthropogenic volatile organic compounds (AVOCs),biogenic volatile organic compounds (BVOCs) and nitrogen oxides (NOx) to daily maximum surface O3(O3DM) concentrations in East Asia in summer (June to August 2000).The summer averaged synergistic impacts of AVOCs and NOx are dominant in most areas of North China,with a maximum of 60 ppbv,while those of BVOCs and NOx are notable only in some limited areas with high BVOC emissions in South China,with a maximum of 25 ppbv.This result implies that BVOCs contribute much less to summer averaged O3DM concentrations than AVOCs in most areas of East Asia at a coarse spatial resolution (1×1) although global emissions of BVOCs are much greater than those of AVOCs.Daily maximum total contributions of BVOCs can approach 20 ppbv in North China,but they can reach 40 ppbv in South China,approaching or exceeding those in some developed countries in Europe and North America.BVOC emissions in such special areas should be considered when O3 control measures are taken.Synergistic contributions among AVOCs,BVOCs and NOx significantly enhance O3 concentrations in the Beijing-Tianjin-Tangshan region and decrease them in some areas in South China.Thus,the total contributions of BVOCs to O3DM vary significantly from day to day and from location to location.This result suggests that O3 control measures obtained from episodic studies could be limited for long-term applications.
文摘The Pearl River Delta (PRD) is one of the most industrialized, urbanized and populated regions in China, and thus has been long suffering from severe air pollutions. Space data provide a unique perspective for investigating the atmospheric environment at a regional scale. By utilizing multiple satellite retrievals from 2005 to 2013, this study presented, for the first time, the spatial patterns and temporal trends of typical air pollutants over PRD and its vicinity. As viewed from space, aerosol optical depth (AOD), NO2 and SO2 all had their higher values at the central part of PRD, and showed clear descending gradients as moving to the outskirt of this region. As to the inter-annual variation, all these pollutants had decreasing trends in PRD during the study period, which generally agreed with the relevant in situ measurements. However, the satellite retrievals differed from ground measurements when addressing NO2 and SO2 in the vicinity of PRD. This work also provides the inter-comparison among PRD and three other metropolitan clusters in China: PRD had relatively high AOD, moderate NO2 and low SO2 levels, and it was the only region achieving the effective reduction of NO2 and SO2 during last decade. Unlike the previous three pollutants, HCHO observed by satellite showed very special patterns: it had a relatively homogeneous spatial distribution over both of PRD and its vicinity, and presented an opposite increasing trend from 2005 to 2010. Moreover, PRD had the highest HCHO level among all the metropolitan clusters, hinting a considerable contribution of biogenic origins of HCHO in PRD.
文摘For the years 2008-2013, particles of diameter 〈 10 and 2.5 μm (PM10 and PM2.5, respectively), NOx, SO2, and O3 concentrations at urban, suburban, rural, and traffic sites in the Paris metropolitan area were analyzed. Strong spatial variability at traffic and rural sites and relatively uniform profiles at urban and suburban sites for PM10, PM2.5, and O3 were observed. The O3 weekend effect was induced by lower NOx emissions during the weekend, and favored volatile organic compounds (VOCs)-limited atmospheric conditions. In conJunction with low ambient temperature, these conditions could also favor increased formation of secondary particulate nitrates in winter. Winter air pollution events were associated with multiple pollutants, whereas those observed in spring were caused by high PM10 and PM2.5 levels. Back- ward trajectory analyses showed the contribution of sources in Western and Central Europe on days with high PM10, PM2.5, and O3, and a local/national comvonent for NOx and SO2.