The Metaverse depicts a parallel digitalized world where virtuality and reality are fused.It has economic and social systems like those in the real world and provides intelligent services and applications.In this pape...The Metaverse depicts a parallel digitalized world where virtuality and reality are fused.It has economic and social systems like those in the real world and provides intelligent services and applications.In this paper,we introduce the Metaverse from a new technology perspective,including its essence,corresponding technical framework,and potential technical challenges.Specifically,we analyze the essence of the Metaverse from its etymology and point out breakthroughs promising to be made in time,space,and contents of the Metaverse by citing Maslow's Hierarchy of Needs.Subsequently,we conclude four pillars of the Metaverse,named ubiquitous connections,space convergence,virtuality and reality interaction,and human-centered communication,and establish a corresponding technical framework.Additionally,we envision open issues and challenges of the Metaverse in the technical aspect.The work proposes a new technology perspective of the Metaverse and will provide further guidance for its technology development in the future.展开更多
In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground a...In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground and diverse, or even irregular, operations in sampling and testing procedures, CRI determination is usually faced with many difficulties and uncertainties. In addition, more difficulties occur in an investigation of a large-scale region because of time constraints and measurement cost limitations. In this study, traditional CRI acquiring methods were summarized first, and then a new complex scheme was established, involving seven core steps and coupling the model estimate and sample measurement. The above CRI determination methodology was implemented in the central-eastern Inner Mongolia Plateau. The case study results showed that the CRI in the dark chestnut soil sub-region, located in the east and south of Xing＇an City, exhibited 2447 Bq·m–2; the CRI in the aeolian sandy soil sub-region, positioned in the south central Tongliao City and central Chifeng City, showed 2430 Bq·m–2; the CRI in the sandy chernozem soil sub-region, situated in the northwestern Chifeng City, presented 2384 Bq·m–2; and the CRI in the chestnut soil sub-region, in the southern Xilin Gol City, was 2368 Bq·m–2. The newly proposed CRI determination scheme was proved effective, and the determined CRI plots and CRI values were convincing. The methodology offered a framework for 137 Cs tracing studies in large-scale regions or long-distance transects.展开更多
文摘The Metaverse depicts a parallel digitalized world where virtuality and reality are fused.It has economic and social systems like those in the real world and provides intelligent services and applications.In this paper,we introduce the Metaverse from a new technology perspective,including its essence,corresponding technical framework,and potential technical challenges.Specifically,we analyze the essence of the Metaverse from its etymology and point out breakthroughs promising to be made in time,space,and contents of the Metaverse by citing Maslow's Hierarchy of Needs.Subsequently,we conclude four pillars of the Metaverse,named ubiquitous connections,space convergence,virtuality and reality interaction,and human-centered communication,and establish a corresponding technical framework.Additionally,we envision open issues and challenges of the Metaverse in the technical aspect.The work proposes a new technology perspective of the Metaverse and will provide further guidance for its technology development in the future.
基金National Key Basic Research Program of China（973 Program）,No.2010CB950904 National Natural Science Foundation of China,No.40971223 Knowledge Innovation Project of CAS,No.KZCX2-EW-306
文摘In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground and diverse, or even irregular, operations in sampling and testing procedures, CRI determination is usually faced with many difficulties and uncertainties. In addition, more difficulties occur in an investigation of a large-scale region because of time constraints and measurement cost limitations. In this study, traditional CRI acquiring methods were summarized first, and then a new complex scheme was established, involving seven core steps and coupling the model estimate and sample measurement. The above CRI determination methodology was implemented in the central-eastern Inner Mongolia Plateau. The case study results showed that the CRI in the dark chestnut soil sub-region, located in the east and south of Xing＇an City, exhibited 2447 Bq·m–2; the CRI in the aeolian sandy soil sub-region, positioned in the south central Tongliao City and central Chifeng City, showed 2430 Bq·m–2; the CRI in the sandy chernozem soil sub-region, situated in the northwestern Chifeng City, presented 2384 Bq·m–2; and the CRI in the chestnut soil sub-region, in the southern Xilin Gol City, was 2368 Bq·m–2. The newly proposed CRI determination scheme was proved effective, and the determined CRI plots and CRI values were convincing. The methodology offered a framework for 137 Cs tracing studies in large-scale regions or long-distance transects.
