The Chinese global carbon dioxide monitoring satellite (TanSat) was launched successfully in December 2016 and has completed its on-orbit tests and calibration. TanSat aims to measure the atmospheric column-averaged...The Chinese global carbon dioxide monitoring satellite (TanSat) was launched successfully in December 2016 and has completed its on-orbit tests and calibration. TanSat aims to measure the atmospheric column-averaged dry air mole fractions of carbon dioxide (XCO2) with a precision of 4 ppm at the regional scale, and in addition, to derive global and regional CO2 fluxes. Progress towards these objectives is reviewed and the first scientific results from TanSat measurements are presented. TanSat on-orbit tests indicate that the Atmospheric Carbon dioxide GratingSpectrometer is in normal working status and is beginning to produce LIB products. The preliminary TanSat XCO2 products have been retrieved by an algorithm and compared to NASA Orbiting Carbon Observatory-2 (OCO-2) measurements during an over- lapping observation period. Furthermore, the XCO2 retrievals have been validated against eight groundsite measurement datasets from the Total Carbon Column Observing Network, for which the preliminary conclusion is that TanSat has met the precision design requirement, with an average bias of 2.11 ppm. The first scientific observations are presented, namely, the seasonal distributions of XCO2 over land on a global scale.展开更多
超声技术自诞生之日起就被称为“未来的听诊器”,是快速、有效和无创的床边诊疗工具。远程超声技术最初是美国国家航空航天局(NationalAeronautics and Space Administration,NASA)开发并应用,使宇航员能够在地面医学专家的指导下进行...超声技术自诞生之日起就被称为“未来的听诊器”,是快速、有效和无创的床边诊疗工具。远程超声技术最初是美国国家航空航天局(NationalAeronautics and Space Administration,NASA)开发并应用,使宇航员能够在地面医学专家的指导下进行实时超声检查。在没有任何其他诊断成像资源的情况下,可进行肌肉骨骼超声、眼部创伤超声甚至创伤重点超声评估(focused assessment withsonography for trauma,FAST)检查[1-4]。随后远程超声技术推广至民用,成为远程医疗的重要组成部分。展开更多
针对区域风光发电资源评估问题,提出一种基于连续小波变换的多尺度评估方法。从美国国家航空航天局(National Aeronautics and Space Administration,NASA)中获取风速和光照强度再分析数据,并利用虚拟发电系统模型预处理为发电容量系数...针对区域风光发电资源评估问题,提出一种基于连续小波变换的多尺度评估方法。从美国国家航空航天局(National Aeronautics and Space Administration,NASA)中获取风速和光照强度再分析数据,并利用虚拟发电系统模型预处理为发电容量系数。综合考虑储量、波动性和互补性等资源属性,构建量化指标对区域风光发电资源进行分析,以时间和空间两个角度挖掘区域资源的分布特征。利用连续小波变换方法提取不同尺度上的风光波动性和互补性特征,评估风光互补发电对出力波动的平抑作用,并探究最佳的互补尺度。以枣庄市为例,对提出方法的有效性进行验证。算例分析表明:风光资源具有波动性和互补性,在最佳尺度上规划互补发电系统能够有效平抑功率波动。展开更多
针对世界时与地球时的差值△T问题,提出了新的拟合多项式。基于美国海军天文台发布的1657年~2020年间的△T数据,以及IERS(International Earth Rmarionand referencesy stems Service,国际地球自转和参考系服务组织)公报中公布的L...针对世界时与地球时的差值△T问题,提出了新的拟合多项式。基于美国海军天文台发布的1657年~2020年间的△T数据,以及IERS(International Earth Rmarionand referencesy stems Service,国际地球自转和参考系服务组织)公报中公布的LS(Leap Seconds,跳秒)数据,在美国NAsA(National Aeronauties and Space Administration,国家航空航天局)经验公式的基础上进行了改进,分别用3次、4次、5次、6次多项式进行拟合。然后,基于最小二乘法得到一组多项式经验公式,可适用于公元纪年、儒略日、简约儒略日以及从J2000.0起算的儒略世纪数等4种时间格式。通过精度计算表明,该组经验公式计算结果与USNO(United States Navy Observatory,美国海军天文台)基准序列的残差不超过±1.29s,与IERS基准序列的残差不超过±0.16s,整体优于NASA经验公式的计算精度。同时还给出了得到更高精度经验公式的拟合方法。展开更多
基金supported by the National Key R & D Program of China (2016YFA0600203)the National High-tech Research and Development Program (2011AA12A104)+1 种基金External Cooperation Program of the Chinese Academy of Sciences (GJHZ1507)the National Key R & D Program of China (2017YFB0504000)
文摘The Chinese global carbon dioxide monitoring satellite (TanSat) was launched successfully in December 2016 and has completed its on-orbit tests and calibration. TanSat aims to measure the atmospheric column-averaged dry air mole fractions of carbon dioxide (XCO2) with a precision of 4 ppm at the regional scale, and in addition, to derive global and regional CO2 fluxes. Progress towards these objectives is reviewed and the first scientific results from TanSat measurements are presented. TanSat on-orbit tests indicate that the Atmospheric Carbon dioxide GratingSpectrometer is in normal working status and is beginning to produce LIB products. The preliminary TanSat XCO2 products have been retrieved by an algorithm and compared to NASA Orbiting Carbon Observatory-2 (OCO-2) measurements during an over- lapping observation period. Furthermore, the XCO2 retrievals have been validated against eight groundsite measurement datasets from the Total Carbon Column Observing Network, for which the preliminary conclusion is that TanSat has met the precision design requirement, with an average bias of 2.11 ppm. The first scientific observations are presented, namely, the seasonal distributions of XCO2 over land on a global scale.
文摘超声技术自诞生之日起就被称为“未来的听诊器”,是快速、有效和无创的床边诊疗工具。远程超声技术最初是美国国家航空航天局(NationalAeronautics and Space Administration,NASA)开发并应用,使宇航员能够在地面医学专家的指导下进行实时超声检查。在没有任何其他诊断成像资源的情况下,可进行肌肉骨骼超声、眼部创伤超声甚至创伤重点超声评估(focused assessment withsonography for trauma,FAST)检查[1-4]。随后远程超声技术推广至民用,成为远程医疗的重要组成部分。
文摘针对区域风光发电资源评估问题,提出一种基于连续小波变换的多尺度评估方法。从美国国家航空航天局(National Aeronautics and Space Administration,NASA)中获取风速和光照强度再分析数据,并利用虚拟发电系统模型预处理为发电容量系数。综合考虑储量、波动性和互补性等资源属性,构建量化指标对区域风光发电资源进行分析,以时间和空间两个角度挖掘区域资源的分布特征。利用连续小波变换方法提取不同尺度上的风光波动性和互补性特征,评估风光互补发电对出力波动的平抑作用,并探究最佳的互补尺度。以枣庄市为例,对提出方法的有效性进行验证。算例分析表明:风光资源具有波动性和互补性,在最佳尺度上规划互补发电系统能够有效平抑功率波动。
文摘针对世界时与地球时的差值△T问题,提出了新的拟合多项式。基于美国海军天文台发布的1657年~2020年间的△T数据,以及IERS(International Earth Rmarionand referencesy stems Service,国际地球自转和参考系服务组织)公报中公布的LS(Leap Seconds,跳秒)数据,在美国NAsA(National Aeronauties and Space Administration,国家航空航天局)经验公式的基础上进行了改进,分别用3次、4次、5次、6次多项式进行拟合。然后,基于最小二乘法得到一组多项式经验公式,可适用于公元纪年、儒略日、简约儒略日以及从J2000.0起算的儒略世纪数等4种时间格式。通过精度计算表明,该组经验公式计算结果与USNO(United States Navy Observatory,美国海军天文台)基准序列的残差不超过±1.29s,与IERS基准序列的残差不超过±0.16s,整体优于NASA经验公式的计算精度。同时还给出了得到更高精度经验公式的拟合方法。