This paper describes the fundamentals of cloud computing and current big-data key technologies. We categorize big-da- ta processing as batch-based, stream-based, graph-based, DAG-based, interactive-based, or visual-ba...This paper describes the fundamentals of cloud computing and current big-data key technologies. We categorize big-da- ta processing as batch-based, stream-based, graph-based, DAG-based, interactive-based, or visual-based according to the processing technique. We highlight the strengths and weaknesses of various big-data cloud processing techniques in order to help the big-data community select the appropri- ate processing technique. We also provide big data research challenges and future directions in aspect to transportation management systems.展开更多
Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS （intelligent transportation systems） and CV （connected veh...Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS （intelligent transportation systems） and CV （connected vehicle） technologies represent a new approach to capturing and using needed transportation data in real time or near real time. In the case of Michigan, several ITS programs have been launched successfully, but independently of each other. The objective of this research is to evaluate and assess all important factors that will influence the collection, management and use of ITS data, and recommend strategies to develop integrated, dynamic and adaptive data management systems for state transportation agencies.展开更多
HY-2 satellite is the first marine dynamic environment satellite of China.In this study,global evaporation and water vapor transport of the global sea surface are calculated on the basis of HY-2 multi-sensor data from...HY-2 satellite is the first marine dynamic environment satellite of China.In this study,global evaporation and water vapor transport of the global sea surface are calculated on the basis of HY-2 multi-sensor data from April 1 to 30,2014.The algorithm of evaporation and water vapor transport is discussed in detail,and results are compared with other reanalysis data.The sea surface temperature of HY-2 is in good agreement with the ARGO buoy data.Two clusters are shown in the scatter plot of HY-2 and OAFlux evaporation due to the uneven global distribution of evaporation.To improve the calculation accuracy,we compared the different parameterization schemes and adopted the method of calibrating HY-2 precipitation data by SSM/I and Global Precipitation Climatology Project(GPCP)data.In calculating the water vapor transport,the adjustment scheme is proposed to match the balance of the water cycle for data in the low latitudes.展开更多
In this paper,the relevance of spatial distribution between urban parks and transportation infrastructure in Beijing was studied grounded on POI data to guarantee the accuracy and scientificity.This paper focused on t...In this paper,the relevance of spatial distribution between urban parks and transportation infrastructure in Beijing was studied grounded on POI data to guarantee the accuracy and scientificity.This paper focused on three aspects.Firstly,based on vector data of Beijing and POI data,the distribution of bus stations,subway stations,and parking lots as well as the road network density in the radiating region of each main entrance in urban parks were analyzed to assess traffic service ability in surrounding area of urban parks.Secondly,coupling relationship of spatial distribution between urban parks and transportation network in Beijing was analyzed using Kernel Density tools.Thirdly,Arc GIS was used to explore space pattern characteristics of large parks and association models between large parks and main transportation network,including two types of intersected and non-intersected and seven models.Finally,according to the comprehensive analysis of POI data,there was a contradictory relationship of interdependency and interaction between space pattern of urban parks and transportation infrastructure construction in Beijing,contributing to the scientific judgment of spatial characteristics of urban parks and transportation infrastructure as well as traffic accessibility and convenience.Quantified conclusions were thus obtained to explore coordinated development strategies for two systems of park green space and transportation network,thereby providing new ideas for the construction of harmonious and livable environment in Beijing.展开更多
The aim of this study was to investigate the link between ambulance transports due to heat stroke and air temperature by using daily data of ambulance transports in Okayama prefecture, Japan. Daily observations for am...The aim of this study was to investigate the link between ambulance transports due to heat stroke and air temperature by using daily data of ambulance transports in Okayama prefecture, Japan. Daily observations for ambulance transports due to heat stroke from July to September in 2010 in Okayama prefecture, Japan were obtained from Fire and Disaster Management Agency in Japan. Data of meteorological parameters in Okayama prefecture, Japan were also obtained from Japan Meteorological Agency. Effect of meteorological parameters on ambulance transports due to heat stroke was analyzed. A total of 1133 ambulance transports due to heat stroke were observed in from July to September of 2010 in Okayama prefecture, Japan. Ambulance transports due to heat stroke was significantly correlated with air temperature. In addition, number of subjects with ambulance transports due to heat stroke over 34°C in the highest air temperature was 21.2 ± 9.8 per day. Higher air temperature was closely associated with higher ambulance transports due to heat stroke by using daily data in Okayama, prefecture, Japan.展开更多
The characteristics of long-distance dust transport from Asia to the United States over the Pacific Ocean are statistically analyzed using OMI AI （Ozone Monitoring Instrument Aerosol Index） data during 2005-007. The...The characteristics of long-distance dust transport from Asia to the United States over the Pacific Ocean are statistically analyzed using OMI AI （Ozone Monitoring Instrument Aerosol Index） data during 2005-007. The results show that there is a high correla- tion of At （the correlation coefficients are as high as 0.83 in March, 0.62 in April and 054 in May） between the Mongolia Gobi Desert and the west coast region of the United States （40°-50°N, 120°- 130°W）, indicating a strong source-receptor area relationship. Through calculating the lag correlation coefficient of the dust propagation time, we determined that the dust propagation lime fi＇om the Mongolia Gobi Desert to the west coast of the United States is about 6-7 days at the 99% confidence level.展开更多
基金supported in part by the National Basic Research Program(973 Program,No.2015CB352400)NSFC under grant U1401258U.S NSF under grant CCF-1016966
文摘This paper describes the fundamentals of cloud computing and current big-data key technologies. We categorize big-da- ta processing as batch-based, stream-based, graph-based, DAG-based, interactive-based, or visual-based according to the processing technique. We highlight the strengths and weaknesses of various big-data cloud processing techniques in order to help the big-data community select the appropri- ate processing technique. We also provide big data research challenges and future directions in aspect to transportation management systems.
文摘Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS （intelligent transportation systems） and CV （connected vehicle） technologies represent a new approach to capturing and using needed transportation data in real time or near real time. In the case of Michigan, several ITS programs have been launched successfully, but independently of each other. The objective of this research is to evaluate and assess all important factors that will influence the collection, management and use of ITS data, and recommend strategies to develop integrated, dynamic and adaptive data management systems for state transportation agencies.
基金the financial support from the National Natural Science Foundation of China (No. 4197 6017)the Ministry of Science and Technology of China (No. 2016YFC1401405)the National Natural Science Foundation of China (No. U1406401)
文摘HY-2 satellite is the first marine dynamic environment satellite of China.In this study,global evaporation and water vapor transport of the global sea surface are calculated on the basis of HY-2 multi-sensor data from April 1 to 30,2014.The algorithm of evaporation and water vapor transport is discussed in detail,and results are compared with other reanalysis data.The sea surface temperature of HY-2 is in good agreement with the ARGO buoy data.Two clusters are shown in the scatter plot of HY-2 and OAFlux evaporation due to the uneven global distribution of evaporation.To improve the calculation accuracy,we compared the different parameterization schemes and adopted the method of calibrating HY-2 precipitation data by SSM/I and Global Precipitation Climatology Project(GPCP)data.In calculating the water vapor transport,the adjustment scheme is proposed to match the balance of the water cycle for data in the low latitudes.
基金Sponsored by National Natural Science Fund of China(51508004)Science and Technology Plans of Ministry of Housing and Urban-Rural Development of the People’s Republic of China,and Opening Projects of Beijing Advanced Innovation Center for Future Urban Design,Beijing University of Civil Engineering and Architecture(UDC2017030712)2018 Beijing Municipal University Academic Human Resources Development-Youth Talent Support Program(PXM2018-014212-000043)
文摘In this paper,the relevance of spatial distribution between urban parks and transportation infrastructure in Beijing was studied grounded on POI data to guarantee the accuracy and scientificity.This paper focused on three aspects.Firstly,based on vector data of Beijing and POI data,the distribution of bus stations,subway stations,and parking lots as well as the road network density in the radiating region of each main entrance in urban parks were analyzed to assess traffic service ability in surrounding area of urban parks.Secondly,coupling relationship of spatial distribution between urban parks and transportation network in Beijing was analyzed using Kernel Density tools.Thirdly,Arc GIS was used to explore space pattern characteristics of large parks and association models between large parks and main transportation network,including two types of intersected and non-intersected and seven models.Finally,according to the comprehensive analysis of POI data,there was a contradictory relationship of interdependency and interaction between space pattern of urban parks and transportation infrastructure construction in Beijing,contributing to the scientific judgment of spatial characteristics of urban parks and transportation infrastructure as well as traffic accessibility and convenience.Quantified conclusions were thus obtained to explore coordinated development strategies for two systems of park green space and transportation network,thereby providing new ideas for the construction of harmonious and livable environment in Beijing.
文摘The aim of this study was to investigate the link between ambulance transports due to heat stroke and air temperature by using daily data of ambulance transports in Okayama prefecture, Japan. Daily observations for ambulance transports due to heat stroke from July to September in 2010 in Okayama prefecture, Japan were obtained from Fire and Disaster Management Agency in Japan. Data of meteorological parameters in Okayama prefecture, Japan were also obtained from Japan Meteorological Agency. Effect of meteorological parameters on ambulance transports due to heat stroke was analyzed. A total of 1133 ambulance transports due to heat stroke were observed in from July to September of 2010 in Okayama prefecture, Japan. Ambulance transports due to heat stroke was significantly correlated with air temperature. In addition, number of subjects with ambulance transports due to heat stroke over 34°C in the highest air temperature was 21.2 ± 9.8 per day. Higher air temperature was closely associated with higher ambulance transports due to heat stroke by using daily data in Okayama, prefecture, Japan.
基金funded by the Project 12ZB020 of the Education Department of Sichuan Province
文摘The characteristics of long-distance dust transport from Asia to the United States over the Pacific Ocean are statistically analyzed using OMI AI （Ozone Monitoring Instrument Aerosol Index） data during 2005-007. The results show that there is a high correla- tion of At （the correlation coefficients are as high as 0.83 in March, 0.62 in April and 054 in May） between the Mongolia Gobi Desert and the west coast region of the United States （40°-50°N, 120°- 130°W）, indicating a strong source-receptor area relationship. Through calculating the lag correlation coefficient of the dust propagation time, we determined that the dust propagation lime fi＇om the Mongolia Gobi Desert to the west coast of the United States is about 6-7 days at the 99% confidence level.
