According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008,our previous estimate of ...According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008,our previous estimate of the average-weighted vertical variation of the Earth＇s solid surface suggests that the Earth＇s solid part is expanding at a rate of 0.24 ± 0.05 mm/a in recent two decades.In another aspect,the satellite altimetry observations spanning recent two decades demonstrate the sea level rise（SLR） rate 3.2 ± 0.4 mm/a,of which1.8 ± 0.5 mm/a is contributed by the ice melting over land.This study shows that the oceanic thermal expansion is 1.0 ± 0.1 mm/a due to the temperature increase in recent half century,which coincides with the estimate provided by previous authors.The SLR observation by altimetry is not balanced by the ice melting and thermal expansion,which is an open problem before this study.However,in this study we infer that the oceanic part of the Earth is expanding at a rate about 0.4 mm/a.Combining the expansion rates of land part and oceanic part,we conclude that the Earth is expanding at a rate of 0.35 ± 0.47 mm/a in recent two decades.If the Earth expands at this rate,then the altimetry-observed SLR can be well explained.展开更多
为有效厘清区块链技术在应急管理中的研究现状,采用系统文献综述(SLR)与系统评价和元分析的首选报告项目审查方法,综合分析从Web of Science和中国知网期刊数据库中确定的与主题相关的58项研究;总结区块链技术在应急管理中应用所面临的...为有效厘清区块链技术在应急管理中的研究现状,采用系统文献综述(SLR)与系统评价和元分析的首选报告项目审查方法,综合分析从Web of Science和中国知网期刊数据库中确定的与主题相关的58项研究;总结区块链技术在应急管理中应用所面临的挑战,并从健全法律和制度体系、加速推进区块链核心技术突破、加强专业化人才队伍建设、实现区块链与其他技术的集成与协同4个方面,展望学术界未来关注的潜在主题。结果表明:区块链技术在应急管理中的应用处于初期的蓬勃发展阶段。当前研究主要围绕数据管理(40.3%),效率提升(40.3%)和概念发展(19.4%)3类主题开展,这3个主题可细化为8个次主题。区块链技术在应急管理中的应用呈现出:技术功能改进的需求,应急数据高效管理的需求,应急数据安全性、完整性和数据共享效率的需求。展开更多
基金supported by National 973 Project China(2013CB733305,2013CB733301)National Natural Science Foundation of China(41174011,41429401,41210006,41128003,41021061)
文摘According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008,our previous estimate of the average-weighted vertical variation of the Earth＇s solid surface suggests that the Earth＇s solid part is expanding at a rate of 0.24 ± 0.05 mm/a in recent two decades.In another aspect,the satellite altimetry observations spanning recent two decades demonstrate the sea level rise（SLR） rate 3.2 ± 0.4 mm/a,of which1.8 ± 0.5 mm/a is contributed by the ice melting over land.This study shows that the oceanic thermal expansion is 1.0 ± 0.1 mm/a due to the temperature increase in recent half century,which coincides with the estimate provided by previous authors.The SLR observation by altimetry is not balanced by the ice melting and thermal expansion,which is an open problem before this study.However,in this study we infer that the oceanic part of the Earth is expanding at a rate about 0.4 mm/a.Combining the expansion rates of land part and oceanic part,we conclude that the Earth is expanding at a rate of 0.35 ± 0.47 mm/a in recent two decades.If the Earth expands at this rate,then the altimetry-observed SLR can be well explained.
文摘为有效厘清区块链技术在应急管理中的研究现状,采用系统文献综述(SLR)与系统评价和元分析的首选报告项目审查方法,综合分析从Web of Science和中国知网期刊数据库中确定的与主题相关的58项研究;总结区块链技术在应急管理中应用所面临的挑战,并从健全法律和制度体系、加速推进区块链核心技术突破、加强专业化人才队伍建设、实现区块链与其他技术的集成与协同4个方面,展望学术界未来关注的潜在主题。结果表明:区块链技术在应急管理中的应用处于初期的蓬勃发展阶段。当前研究主要围绕数据管理(40.3%),效率提升(40.3%)和概念发展(19.4%)3类主题开展,这3个主题可细化为8个次主题。区块链技术在应急管理中的应用呈现出:技术功能改进的需求,应急数据高效管理的需求,应急数据安全性、完整性和数据共享效率的需求。
