In the metropolises of China, the metro plays an increasingly important role in commuting because of its efficiency, affordability, and cleanliness. This paper attempts to explore the relationship between walking acce...In the metropolises of China, the metro plays an increasingly important role in commuting because of its efficiency, affordability, and cleanliness. This paper attempts to explore the relationship between walking access distance to metro stations and the demographic characteristics of passengers, such as age, monthly income, travel frequency, gender, and travel purpose, as well as the influence of the urban context. Nanjing Metro Line 2 is selected as the case study. By using different methods such as a questionnaire survey, spatial decay function, analysis of covariance(ANOVA), network analysis of routes, and K-means cluster analysis, it is suggested that demographic characteristics have a significant impact on the pedestrian walking distance, with the exception of gender. Furthermore, the paper finds a spatial decay effect in walking access distance, the decay rate of which, however, varies across stations. Terminal stations have a larger pedestrian catchment area than in regular and exchange stations. Moreover, the passengers of Nanjing Metro Line 2 can be classified into six groups according to their demographic characteristics, among which education and occupation are vital indicators in determining their willingness to walk to the stations. Middle-class passengers have a higher dependence on the metro and tend to walk longer than other groups do. This study provides an important reference for planners and transport sectors to optimize land-use and transport infrastructures.展开更多
The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust haz...The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust hazards. The carbon sequestration dynamics can be used to assess the ecological effects of an ecological restoration project. Here, we conducted vegetation and soil study to assess the carbon sequestration in the plantations with 10 years old stands in Beijing-Tianjin sand source areas. The results at the site scales indicated that the average net increase of plantation ecosystem carbon stock was 33.8 Mg C ha^(-1), with an annual increase rate of 3.38 Mg C ha^(-1) yr^(-1). The average net increase of carbon varied among regions, vegetation types, and forest management activities. Soil bulk density in the top soil decreased slightly after 10-year implementation of the project. Coniferous forests and shrubs are suitable plant species for sand source areas.Natural restoration in the plantations is a practical and feasible and promising approach for enhancing ecosystem carbon sequestration potential.展开更多
In this paper,a hindcast study of the record-breaking rainfall event occurring in Beijing on 21July 2012,is conducted by using the Weather Research and Forecasting(WRF)model forced by National Centers for Environmenta...In this paper,a hindcast study of the record-breaking rainfall event occurring in Beijing on 21July 2012,is conducted by using the Weather Research and Forecasting(WRF)model forced by National Centers for Environmental Prediction(NCEP)Global Forecasting System(GFS)outputs,paired with an investigation of the impact of topography in this region.The results indicate that WRF can reasonably predict the salient features of orographic precipitation;the 24-h rainfall amount and spatial distribution compare reasonably well with the observations.The hindcast simulation also indicates that rainfall events can be predicted approximately 36 h ahead.When the topography is removed,the spatial distribution of rainfall changes remarkably,suggesting the importance of the topography in determining rainfall structure.These results also indicate that prediction of such city-scale heavy rainfall events would benefit from a high-resolution prediction system.展开更多
Objective To retrospectively evaluate the diagnosis and treatment of Mirizzi syndrome (MS). Methods Patients who received elective or emergency cholecystectomies in our center during 23 years were retrospectively e...Objective To retrospectively evaluate the diagnosis and treatment of Mirizzi syndrome (MS). Methods Patients who received elective or emergency cholecystectomies in our center during 23 years were retrospectively evaluated. The data reviewed included demography, clinical presentations, diagnostic methods, surgical procedures, postoperative complications, and follow-up.展开更多
Urban plants provide various ecosystem services and biodiversity for human well-being. It is necessary to examine the plant species and functional traits composition and the influencing factors. In this study, a field...Urban plants provide various ecosystem services and biodiversity for human well-being. It is necessary to examine the plant species and functional traits composition and the influencing factors. In this study, a field survey was conducted using the tessellation-randomized plot method to assess the plant species and functional traits variability in greenspaces across eight land use types(LUTs) in the built-up areas of Beijing, China. Results showed that the woody plants in the built-up areas of Beijing comprised 85 non-native species(57%), 21 pollen-allergenic species(14%), and 99 resistant species(67%). Residential areas, community parks and institutional areas had higher woody plant species richness than other LUTs. Native and extralimital native species were more widespread than exotic species. Proportions of species with resistances were low except for cold-and drought-resistance; consequently, a high intensity of management and maintenance is essential for survival of plants in this urban area. Caution should be exerted in selecting plant species with resistance to harsh conditions in different LUTs. Housing prices, distances from the urban center, years since the establishment of LUTs and greening rate were strongly correlated with the plant functional traits and species diversity. Urban forest managers should consider plant functional traits and LUT-specific strategies to maximize both forest and human health.展开更多
As the most important ecosystem in Beijing, the forest supports a lot of ecosystem services to local and around communities, which plays a key role in the maintenance of urban ecological security.However, the valuatio...As the most important ecosystem in Beijing, the forest supports a lot of ecosystem services to local and around communities, which plays a key role in the maintenance of urban ecological security.However, the valuation on the forest ecosystem services based on regional scale could not provide precise and reasonable values for forestry sector management.In this study, we estimated the magnitudes and economic values of the forest ecosystem services in Beijing at sublot level.The economic value of forest ecosystem services in Beijing was estimated to be 19 339.71×10 6 yuan(RMB) in 2004.Among all the ecosystem services indicators we estimated in this study, only fruit, timber and part of the recreation(which only include the tourism income from the forest parks and scenic areas, but not include that from other forest types) were measured in the social economic system.As estimated in this study, more than 82.19% of the economic value of forest ecosystem services could not be measured in the socio-economic statistical system.The importance of forest ecosystem services in Beijing to human welfare was underestimated by the socio-economic system.Therefore, the policies about the eco-compensation of forest ecosystem services should be established to maintain the sustainable supply of the forest ecosystem services in Beijing.展开更多
Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and re...Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and release travel information to travelers, to provide optimal path options to ensure that the transport system operates efficiently and safely, we have to monitor the changing of the state of road traffic and to accurately evaluate the state of the traffic, then to predict the future state of traffic. This paper represents the construction of the road traffic flow simulation including the logical structure and the physical structure, and introduces the system functions of forecasting system in Beijing.展开更多
Miyun County,located in the northeast of Chinese capital Beijing,was underwent remarkable variations in land use in recent years.This paper aimed to detect changes in land use of Miyun from 1997 to 2005,and to qualify...Miyun County,located in the northeast of Chinese capital Beijing,was underwent remarkable variations in land use in recent years.This paper aimed to detect changes in land use of Miyun from 1997 to 2005,and to qualify the response of ecosystem to LUCC based on ecosystem services valuation.With two-periods TM images,we got land use change data,and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi.Results showed that water area,farm land and unused land decreased while residential land,forest land,grassland and orchard land increased during the study period.The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area.As for spatial variation,there were most dramatically land use change and ESV decline in reservoir ecological protection region.The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable.The driving forces of ESV loss were rapid population growth and economic development.More work should be done to make eco-environment stay healthy.展开更多
This paper presents debris-flow numerical simulations using the Hyper KANAKO system,developed by the authors.The system uses the debris flow simulator KANAKO 2D equipped with a graphical user interface(GUI);hence,a us...This paper presents debris-flow numerical simulations using the Hyper KANAKO system,developed by the authors.The system uses the debris flow simulator KANAKO 2D equipped with a graphical user interface(GUI);hence,a user can easily produce appropriate landform data for simulations using standard laser profiler data,and visualize the results using a GIS.Hyper KANAKO was applied to the streams around Kiyomizu-dera in Kyoto,Japan.Kiyomizu-dera is a famous temple in Japan which is visited by numerous tourists throughout the year.We simulated a disaster scenario of debris flow caused by torrential rain.We set the hydrograph using rainfall intensity data,and set the landform data using information from the Geospatial Information Authority of Japan(GSI) and a digital elevation model(DEM).We evaluated different mesh sizes and also used a digital surface model(DSM) to consider the building heights.The simulation results showed that with small mesh size,the debris flowmoved through the roads,which seems realistic for a disaster situation.When buildings were considered,the flow direction changed,and a 1-m flow depth,which was deeper than in other cases,appeared in the flow path.This may pose a dangerous situation for evacuations.展开更多
The successful experiences that cause Peking Female Higher Normal College (PKFHNC) to complete a relatively large scale of talents training task and become the birthplace of modern female intellectuals in early 20th...The successful experiences that cause Peking Female Higher Normal College (PKFHNC) to complete a relatively large scale of talents training task and become the birthplace of modern female intellectuals in early 20th century China in spite of disorder of social circumstance outside and regular educational system inside are as follows. First, with the endeavor of Chen Zhongfan, Dean of Chinese Department, PKFHNC gathered lots of leading scholars both from old school and new school during May Fourth Movement; second, these leading scholars' diversified academic thoughts, political ideas, and educational experiences encouraged students to think freely and critically; finally, their deep concerns about the future of China society, academic disciplines, and women's liberation and education caused all superficial changes and differences of PKFHNC to form an united spiritual power, which promoted this group of female students' development deeply.展开更多
The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main i...The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main information on the experiments including the experiment purpose, design, and the external forcings. The transient climate responses to the CO2 concentration increase at 1% per year are presented in the simulation of the two models. The BCC_CSM1.1-M result is closer to the CMIP5 multiple models ensemble. The two models perform well in simulating the historical evolution of the surface air temperature, globally and averaged for China. Both models overestimate the global warming and underestimate the warming over China in the 20th century. With higher horizontal resolution, the BCC_CSM1.1-M has a better capability in reproducing the annual evolution of surface air temperature over China.展开更多
Chinese martial arts have a long history, profound, which is an integral part of Chinese traditional culture of grandeur. China joined the WTO and the Beijing Olympic Games "has a rich cultural heritage of thousands ...Chinese martial arts have a long history, profound, which is an integral part of Chinese traditional culture of grandeur. China joined the WTO and the Beijing Olympic Games "has a rich cultural heritage of thousands of years of Chinese martial arts with its unique charm and much of the world' s attention." In the face of opportunities and challenges, the international spread of martial arts has become an irresistible trend. "First of propagation, the spread of the concept of martial arts and martial arts were defined international spread, and it were explains martial international spread of cultural level societal level and significance of the economic level, dialectical judge the outcome of the international transmission acquired with the problems." Secondly, the traditional martial arts culture for martial international dissemination presented aphasia phenomenon, by means of the analysis of the advanced nature of martial arts culture, the martial arts and cultural heritage considered as the center of gravity advantages, not only to absorb the multicultural essence of martial arts culture useful, but also highlight the ethnic characteristics of martial arts culture, martial arts culture to enhance capacity external radiation, the Chinese martial arts as a complete all- round cultural forms, multi-level, multi-an^le display, promote the Chinese martial arts to the world in a more in-depth. "展开更多
Due to long-term over-exploitation of groundwater in Beijing Municipality, regional groundwater funnels have formed and land subsidence has been induced. By combining a groundwater monitoring network, GPS monitor- ing...Due to long-term over-exploitation of groundwater in Beijing Municipality, regional groundwater funnels have formed and land subsidence has been induced. By combining a groundwater monitoring network, GPS monitor- ing network data, radar satellite SAR data, GIS and other new technologies, a coupled process model based on the dy- namic variation of groundwater and the deformation response of land subsidence has been established. The dynamic variation of groundwater fimnels and the land subsidence response process were analyzed systematically in Beijing. Study results indicate that current groundwater funnel areas are distributed mainly in the southwest of Shunyi District, the northeast of Chaoyang District and the northwest of Tongzhou District, with an average decline rate of groundwa- ter level of 2.66 rn/yr and a maximum of 3.82 m/yr in the center of the funnels. Seasonal and interannual differences exist in the response model of land subsidence to groundwater funnels with uneven spatial and temporal distribution, where the maximum land subsidence rate was about --41.08 mm/yr and the area with a subsidence rate greater than 30 mm/yr was about 1637.29 km2. Although a consistency was revealed to exist between a groundwater funnel and the spatial distribution characteristics of the corresponding land subsidence funnel, this consistency was not perfect. The results showed that the response model of land subsidence to the dynamic variation of groundwater was more revealing when combining conventional technologies with InSAR, GIS, GPS, providing a new strategy for environmental and hydrogeological research and a scientific basis for regional land subsidence control.展开更多
The purpose of this article is to classify the regional economic types and development dynamics of small towns in suburb Beijing by applying the classification methods developed by Nelson's method and Location Quo...The purpose of this article is to classify the regional economic types and development dynamics of small towns in suburb Beijing by applying the classification methods developed by Nelson's method and Location Quotient method into 183 small towns in Beijing.Four types of small towns are thus identified,including urban agriculture dominated towns,manufacturing dominated towns,service industry dominated towns and comprehensive type towns with balanced economic development.Within the environment of geographical information system,the spatial distribution pattern of four types of small towns with their evolution trend is analyzed.The results indicate that four types of small towns have obvious'core-periphery'spatial structure but with different functional orientations and evolution mechanisms.Based on this,the different development strategies for each type of small towns are summarized,providing a scientific reference for the differentiating planning and development strategies of these small towns.展开更多
This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrog...This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrogen storage and delivery system, the hydrogen leakage alarm system were developed. The real-time distributed control and diagnosis system based on the Time Trigger Controller Area Network (TTCAN) with 10 ms basic control period was developed. The concept and implementation of processor (or controller) monitor and process (or task) monitor technique based on the TYCAN were applied in this paper. The fault tolerant control algorithm of the fuel cell engine and the battery man- agement system were considered. The demonstration experience verified that the fault tolerant control was very important for the fuel cell city bus.展开更多
Organic vegetables, does not use pesticides, synthetic fertilizers, herbicides, growth regulators in production process and refers to organisms and products got from genetic engineering. It follows the laws of nature ...Organic vegetables, does not use pesticides, synthetic fertilizers, herbicides, growth regulators in production process and refers to organisms and products got from genetic engineering. It follows the laws of nature and ecological principles, adopts a series of sustainable development of agricultural technology, to coordinate planting balanced, and stable agricultural ecosystems, and through the identification of organic certification, it will be recognized and awarded organic certification. Beijing Country Fair launched by a group of consumer volunteers concerned about ecological agriculture and rural issues, aiming to build a platform for farmers engaged in organic agriculture and consumers can communicate directly, exchange. It can help consumers find safe, assured products, but also help farmers to broaden market channels and encourage more farmers to engage in organic farming, thereby reducing environmental pollution produced by fertilizer and pesticide, safeguarding food security, and practicing fair trade.展开更多
Hanzi (Chinese characters) has a long history and affluent contents. To promote the popularity of historical and cultural knowledge of Chinese characters, an online program has been launched by Beihang University an...Hanzi (Chinese characters) has a long history and affluent contents. To promote the popularity of historical and cultural knowledge of Chinese characters, an online program has been launched by Beihang University and Beijing Normal University to explain Chinese characters' original meanings and evolution processes with vivid and expressive animation videos. Currently, More than 1,000 videos can be accessed through the website “http://www.chinesecharacter.org/”. Besides these online resources, a human-computer interaction system is also proposed to simulate clerical changes of Chinese characters through computer morphing technology. What we want is to make the teaching and learning of Chinese characters more reasonable, more easily understandable and more interesting.展开更多
A large magnitude-9.0 earthquake struck northeast Japan on March 11, 2011. Thirty minutes later, a tsunami reached Tokyo Electric Power Corporation (TEPCO)'s Fukushima Daiichi nuclear power station, and the emergen...A large magnitude-9.0 earthquake struck northeast Japan on March 11, 2011. Thirty minutes later, a tsunami reached Tokyo Electric Power Corporation (TEPCO)'s Fukushima Daiichi nuclear power station, and the emergency diesel generators submerged under water. Three units of the reactor experienced meltdown, and hydrogen explosions occurred at reactor houses. The RIKEN Nishina Center (RNC) contributed to the radiation screening effort by providing human resources, instruments, and transportation. The RNC also carried out extraction work and sample tests for soil contamination. Last summer, RIKEN was legally required to save 15% (equivalent to 3.3 MW) of its allocated electricity in its contract, making it extremely difficult to conduct experiments using accelerators. Accelerator operation was thus reduced to a minimum during the first half of the year. The RNC has a gas-turbine-based co-generation system (CGS) with an electrical capacity of 6.5 MW. The CGS was operated non-stop until the end of the year. RIKEN is constructing two sets of CGSs, each with a capacity of 1.5 MW to be commissioned this autumn.展开更多
Soil dynamic parameters,including dynamic shear modulus ratio and damping ratio,have important effects on the results of layered soil earthquake response. In this paper,the mean parameter values of silty clay in diffe...Soil dynamic parameters,including dynamic shear modulus ratio and damping ratio,have important effects on the results of layered soil earthquake response. In this paper,the mean parameter values of silty clay in different depths are obtained after statistical analysis of the experimental soil dynamic data from 20 recent site seismic safety evaluation reports in the Beijing area. Furthermore,based on two typical engineering sites,the influence of four different soil dynamic parameters,the statistic mean values,experimental values, values recommended by Yuan Xiaoming,and the values recommended in the code for seismic safety evaluation of engineering sites( DB001-94) are analyzed. The result shows that mean statistical values are applicable to seismic safety evaluation work in the Beijing area,especially for some inter-layered silty clays whose undisturbed soil samples are hard to obtain.展开更多
基金Under the auspices of National Nature Science Foundation of China(No.41701180)
文摘In the metropolises of China, the metro plays an increasingly important role in commuting because of its efficiency, affordability, and cleanliness. This paper attempts to explore the relationship between walking access distance to metro stations and the demographic characteristics of passengers, such as age, monthly income, travel frequency, gender, and travel purpose, as well as the influence of the urban context. Nanjing Metro Line 2 is selected as the case study. By using different methods such as a questionnaire survey, spatial decay function, analysis of covariance(ANOVA), network analysis of routes, and K-means cluster analysis, it is suggested that demographic characteristics have a significant impact on the pedestrian walking distance, with the exception of gender. Furthermore, the paper finds a spatial decay effect in walking access distance, the decay rate of which, however, varies across stations. Terminal stations have a larger pedestrian catchment area than in regular and exchange stations. Moreover, the passengers of Nanjing Metro Line 2 can be classified into six groups according to their demographic characteristics, among which education and occupation are vital indicators in determining their willingness to walk to the stations. Middle-class passengers have a higher dependence on the metro and tend to walk longer than other groups do. This study provides an important reference for planners and transport sectors to optimize land-use and transport infrastructures.
基金supported by the National Key Research and Development Program of China(2016YFC0500802)the "Strategic Priority Research Program" of the Chinese Academy of Sciences(XDA05060600)+1 种基金Visiting Scholars Program of ported by Chinese Academy of SciencesYouth Innovation Promotion Association,CAS(2014083)
文摘The Beijing-Tianjin Sand Source Control Project(BTSSCP), a national ecological restoration project, was launched to construct an ecological protection system in the Beijing-Tianjin sand source areas to reduce dust hazards. The carbon sequestration dynamics can be used to assess the ecological effects of an ecological restoration project. Here, we conducted vegetation and soil study to assess the carbon sequestration in the plantations with 10 years old stands in Beijing-Tianjin sand source areas. The results at the site scales indicated that the average net increase of plantation ecosystem carbon stock was 33.8 Mg C ha^(-1), with an annual increase rate of 3.38 Mg C ha^(-1) yr^(-1). The average net increase of carbon varied among regions, vegetation types, and forest management activities. Soil bulk density in the top soil decreased slightly after 10-year implementation of the project. Coniferous forests and shrubs are suitable plant species for sand source areas.Natural restoration in the plantations is a practical and feasible and promising approach for enhancing ecosystem carbon sequestration potential.
基金supported by the National Basic Research Program of China(Grant 2012CB955401)the"Strategic Priority Research Program"of the Chinese Academy of Sciences(Grant XDB03020600)
文摘In this paper,a hindcast study of the record-breaking rainfall event occurring in Beijing on 21July 2012,is conducted by using the Weather Research and Forecasting(WRF)model forced by National Centers for Environmental Prediction(NCEP)Global Forecasting System(GFS)outputs,paired with an investigation of the impact of topography in this region.The results indicate that WRF can reasonably predict the salient features of orographic precipitation;the 24-h rainfall amount and spatial distribution compare reasonably well with the observations.The hindcast simulation also indicates that rainfall events can be predicted approximately 36 h ahead.When the topography is removed,the spatial distribution of rainfall changes remarkably,suggesting the importance of the topography in determining rainfall structure.These results also indicate that prediction of such city-scale heavy rainfall events would benefit from a high-resolution prediction system.
文摘Objective To retrospectively evaluate the diagnosis and treatment of Mirizzi syndrome (MS). Methods Patients who received elective or emergency cholecystectomies in our center during 23 years were retrospectively evaluated. The data reviewed included demography, clinical presentations, diagnostic methods, surgical procedures, postoperative complications, and follow-up.
基金Under the auspices of National Natural Science Foundation of China(No.31600376,41571053,71533005)
文摘Urban plants provide various ecosystem services and biodiversity for human well-being. It is necessary to examine the plant species and functional traits composition and the influencing factors. In this study, a field survey was conducted using the tessellation-randomized plot method to assess the plant species and functional traits variability in greenspaces across eight land use types(LUTs) in the built-up areas of Beijing, China. Results showed that the woody plants in the built-up areas of Beijing comprised 85 non-native species(57%), 21 pollen-allergenic species(14%), and 99 resistant species(67%). Residential areas, community parks and institutional areas had higher woody plant species richness than other LUTs. Native and extralimital native species were more widespread than exotic species. Proportions of species with resistances were low except for cold-and drought-resistance; consequently, a high intensity of management and maintenance is essential for survival of plants in this urban area. Caution should be exerted in selecting plant species with resistance to harsh conditions in different LUTs. Housing prices, distances from the urban center, years since the establishment of LUTs and greening rate were strongly correlated with the plant functional traits and species diversity. Urban forest managers should consider plant functional traits and LUT-specific strategies to maximize both forest and human health.
基金Under the auspices of Major State Basic Research Development Program of China (No. 2009CB421106)National Natural Science Foundation of China (No. 30770410)
文摘As the most important ecosystem in Beijing, the forest supports a lot of ecosystem services to local and around communities, which plays a key role in the maintenance of urban ecological security.However, the valuation on the forest ecosystem services based on regional scale could not provide precise and reasonable values for forestry sector management.In this study, we estimated the magnitudes and economic values of the forest ecosystem services in Beijing at sublot level.The economic value of forest ecosystem services in Beijing was estimated to be 19 339.71×10 6 yuan(RMB) in 2004.Among all the ecosystem services indicators we estimated in this study, only fruit, timber and part of the recreation(which only include the tourism income from the forest parks and scenic areas, but not include that from other forest types) were measured in the social economic system.As estimated in this study, more than 82.19% of the economic value of forest ecosystem services could not be measured in the socio-economic statistical system.The importance of forest ecosystem services in Beijing to human welfare was underestimated by the socio-economic system.Therefore, the policies about the eco-compensation of forest ecosystem services should be established to maintain the sustainable supply of the forest ecosystem services in Beijing.
基金Key Projects in Science & Technology Pillar Program in 2007 in Beijing (No.D07020601400705)
文摘Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and release travel information to travelers, to provide optimal path options to ensure that the transport system operates efficiently and safely, we have to monitor the changing of the state of road traffic and to accurately evaluate the state of the traffic, then to predict the future state of traffic. This paper represents the construction of the road traffic flow simulation including the logical structure and the physical structure, and introduces the system functions of forecasting system in Beijing.
基金supported by the Hi-tech Research and Development Program of China(Grant No.2006AA120108)
文摘Miyun County,located in the northeast of Chinese capital Beijing,was underwent remarkable variations in land use in recent years.This paper aimed to detect changes in land use of Miyun from 1997 to 2005,and to qualify the response of ecosystem to LUCC based on ecosystem services valuation.With two-periods TM images,we got land use change data,and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi.Results showed that water area,farm land and unused land decreased while residential land,forest land,grassland and orchard land increased during the study period.The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area.As for spatial variation,there were most dramatically land use change and ESV decline in reservoir ecological protection region.The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable.The driving forces of ESV loss were rapid population growth and economic development.More work should be done to make eco-environment stay healthy.
基金supported by JSPS KAKENHI Grant No.24710206,Grant-in-Aid for Young Scientists (B)
文摘This paper presents debris-flow numerical simulations using the Hyper KANAKO system,developed by the authors.The system uses the debris flow simulator KANAKO 2D equipped with a graphical user interface(GUI);hence,a user can easily produce appropriate landform data for simulations using standard laser profiler data,and visualize the results using a GIS.Hyper KANAKO was applied to the streams around Kiyomizu-dera in Kyoto,Japan.Kiyomizu-dera is a famous temple in Japan which is visited by numerous tourists throughout the year.We simulated a disaster scenario of debris flow caused by torrential rain.We set the hydrograph using rainfall intensity data,and set the landform data using information from the Geospatial Information Authority of Japan(GSI) and a digital elevation model(DEM).We evaluated different mesh sizes and also used a digital surface model(DSM) to consider the building heights.The simulation results showed that with small mesh size,the debris flowmoved through the roads,which seems realistic for a disaster situation.When buildings were considered,the flow direction changed,and a 1-m flow depth,which was deeper than in other cases,appeared in the flow path.This may pose a dangerous situation for evacuations.
基金Project funded by China Postdoctoral Science Foundation (2016M590648).
文摘The successful experiences that cause Peking Female Higher Normal College (PKFHNC) to complete a relatively large scale of talents training task and become the birthplace of modern female intellectuals in early 20th century China in spite of disorder of social circumstance outside and regular educational system inside are as follows. First, with the endeavor of Chen Zhongfan, Dean of Chinese Department, PKFHNC gathered lots of leading scholars both from old school and new school during May Fourth Movement; second, these leading scholars' diversified academic thoughts, political ideas, and educational experiences encouraged students to think freely and critically; finally, their deep concerns about the future of China society, academic disciplines, and women's liberation and education caused all superficial changes and differences of PKFHNC to form an united spiritual power, which promoted this group of female students' development deeply.
基金supported by the National Basic Research Program of China (973 Program) under No. 2010CB951903the National Science Foundation of China under Grant No. 41105054, 41205043the China Meteorological Administration under Grant No.GYHY201106022, GYHY201306048, CMAYBY2012-001
文摘The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main information on the experiments including the experiment purpose, design, and the external forcings. The transient climate responses to the CO2 concentration increase at 1% per year are presented in the simulation of the two models. The BCC_CSM1.1-M result is closer to the CMIP5 multiple models ensemble. The two models perform well in simulating the historical evolution of the surface air temperature, globally and averaged for China. Both models overestimate the global warming and underestimate the warming over China in the 20th century. With higher horizontal resolution, the BCC_CSM1.1-M has a better capability in reproducing the annual evolution of surface air temperature over China.
文摘Chinese martial arts have a long history, profound, which is an integral part of Chinese traditional culture of grandeur. China joined the WTO and the Beijing Olympic Games "has a rich cultural heritage of thousands of years of Chinese martial arts with its unique charm and much of the world' s attention." In the face of opportunities and challenges, the international spread of martial arts has become an irresistible trend. "First of propagation, the spread of the concept of martial arts and martial arts were defined international spread, and it were explains martial international spread of cultural level societal level and significance of the economic level, dialectical judge the outcome of the international transmission acquired with the problems." Secondly, the traditional martial arts culture for martial international dissemination presented aphasia phenomenon, by means of the analysis of the advanced nature of martial arts culture, the martial arts and cultural heritage considered as the center of gravity advantages, not only to absorb the multicultural essence of martial arts culture useful, but also highlight the ethnic characteristics of martial arts culture, martial arts culture to enhance capacity external radiation, the Chinese martial arts as a complete all- round cultural forms, multi-level, multi-an^le display, promote the Chinese martial arts to the world in a more in-depth. "
基金Under the auspices of Program of International S&T Cooperation (No. 2010DFA92400)Non-profit Industry Financial Program of the Ministry of Water Resources (No. 200901091)+2 种基金Beijing Municipal Natural Science Foundation (No. 8101002)Beijing Municipal Education Commission Plans to Focus Science and Technology Projects (No. KZ201010028030)National Natural Science Foundation of China (No. 41130744,41171335)
文摘Due to long-term over-exploitation of groundwater in Beijing Municipality, regional groundwater funnels have formed and land subsidence has been induced. By combining a groundwater monitoring network, GPS monitor- ing network data, radar satellite SAR data, GIS and other new technologies, a coupled process model based on the dy- namic variation of groundwater and the deformation response of land subsidence has been established. The dynamic variation of groundwater fimnels and the land subsidence response process were analyzed systematically in Beijing. Study results indicate that current groundwater funnel areas are distributed mainly in the southwest of Shunyi District, the northeast of Chaoyang District and the northwest of Tongzhou District, with an average decline rate of groundwa- ter level of 2.66 rn/yr and a maximum of 3.82 m/yr in the center of the funnels. Seasonal and interannual differences exist in the response model of land subsidence to groundwater funnels with uneven spatial and temporal distribution, where the maximum land subsidence rate was about --41.08 mm/yr and the area with a subsidence rate greater than 30 mm/yr was about 1637.29 km2. Although a consistency was revealed to exist between a groundwater funnel and the spatial distribution characteristics of the corresponding land subsidence funnel, this consistency was not perfect. The results showed that the response model of land subsidence to the dynamic variation of groundwater was more revealing when combining conventional technologies with InSAR, GIS, GPS, providing a new strategy for environmental and hydrogeological research and a scientific basis for regional land subsidence control.
基金supported by the National Natural Science Foundation' Urban Agriculture-based Development Pattern and Spatial Reconstruction of Towns/Townships in Periurban Beijing'(Grant no.40971100)the knowledge innovation project of Chinese Academy of Science' Study on spatial structural reorganization and its effect on eco-environment'(Grant no.KZCX2- YW-321-01)
文摘The purpose of this article is to classify the regional economic types and development dynamics of small towns in suburb Beijing by applying the classification methods developed by Nelson's method and Location Quotient method into 183 small towns in Beijing.Four types of small towns are thus identified,including urban agriculture dominated towns,manufacturing dominated towns,service industry dominated towns and comprehensive type towns with balanced economic development.Within the environment of geographical information system,the spatial distribution pattern of four types of small towns with their evolution trend is analyzed.The results indicate that four types of small towns have obvious'core-periphery'spatial structure but with different functional orientations and evolution mechanisms.Based on this,the different development strategies for each type of small towns are summarized,providing a scientific reference for the differentiating planning and development strategies of these small towns.
文摘This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrogen storage and delivery system, the hydrogen leakage alarm system were developed. The real-time distributed control and diagnosis system based on the Time Trigger Controller Area Network (TTCAN) with 10 ms basic control period was developed. The concept and implementation of processor (or controller) monitor and process (or task) monitor technique based on the TYCAN were applied in this paper. The fault tolerant control algorithm of the fuel cell engine and the battery man- agement system were considered. The demonstration experience verified that the fault tolerant control was very important for the fuel cell city bus.
文摘Organic vegetables, does not use pesticides, synthetic fertilizers, herbicides, growth regulators in production process and refers to organisms and products got from genetic engineering. It follows the laws of nature and ecological principles, adopts a series of sustainable development of agricultural technology, to coordinate planting balanced, and stable agricultural ecosystems, and through the identification of organic certification, it will be recognized and awarded organic certification. Beijing Country Fair launched by a group of consumer volunteers concerned about ecological agriculture and rural issues, aiming to build a platform for farmers engaged in organic agriculture and consumers can communicate directly, exchange. It can help consumers find safe, assured products, but also help farmers to broaden market channels and encourage more farmers to engage in organic farming, thereby reducing environmental pollution produced by fertilizer and pesticide, safeguarding food security, and practicing fair trade.
文摘Hanzi (Chinese characters) has a long history and affluent contents. To promote the popularity of historical and cultural knowledge of Chinese characters, an online program has been launched by Beihang University and Beijing Normal University to explain Chinese characters' original meanings and evolution processes with vivid and expressive animation videos. Currently, More than 1,000 videos can be accessed through the website “http://www.chinesecharacter.org/”. Besides these online resources, a human-computer interaction system is also proposed to simulate clerical changes of Chinese characters through computer morphing technology. What we want is to make the teaching and learning of Chinese characters more reasonable, more easily understandable and more interesting.
文摘A large magnitude-9.0 earthquake struck northeast Japan on March 11, 2011. Thirty minutes later, a tsunami reached Tokyo Electric Power Corporation (TEPCO)'s Fukushima Daiichi nuclear power station, and the emergency diesel generators submerged under water. Three units of the reactor experienced meltdown, and hydrogen explosions occurred at reactor houses. The RIKEN Nishina Center (RNC) contributed to the radiation screening effort by providing human resources, instruments, and transportation. The RNC also carried out extraction work and sample tests for soil contamination. Last summer, RIKEN was legally required to save 15% (equivalent to 3.3 MW) of its allocated electricity in its contract, making it extremely difficult to conduct experiments using accelerators. Accelerator operation was thus reduced to a minimum during the first half of the year. The RNC has a gas-turbine-based co-generation system (CGS) with an electrical capacity of 6.5 MW. The CGS was operated non-stop until the end of the year. RIKEN is constructing two sets of CGSs, each with a capacity of 1.5 MW to be commissioned this autumn.
基金sponsored jointly by the Research Grants from Institute of Crustal Dynamics,CEA(NO. ZDJ2007-7)the 2007 Special Research Project 8-50 of the Department of Finance
文摘Soil dynamic parameters,including dynamic shear modulus ratio and damping ratio,have important effects on the results of layered soil earthquake response. In this paper,the mean parameter values of silty clay in different depths are obtained after statistical analysis of the experimental soil dynamic data from 20 recent site seismic safety evaluation reports in the Beijing area. Furthermore,based on two typical engineering sites,the influence of four different soil dynamic parameters,the statistic mean values,experimental values, values recommended by Yuan Xiaoming,and the values recommended in the code for seismic safety evaluation of engineering sites( DB001-94) are analyzed. The result shows that mean statistical values are applicable to seismic safety evaluation work in the Beijing area,especially for some inter-layered silty clays whose undisturbed soil samples are hard to obtain.