Satellite Internet of Things(IoT)is a promising way to provide seamless coverage to a massive number of devices all over the world,especially in remote areas not covered by cellular networks,e.g.,forests,oceans,mounta...Satellite Internet of Things(IoT)is a promising way to provide seamless coverage to a massive number of devices all over the world,especially in remote areas not covered by cellular networks,e.g.,forests,oceans,mountains,and deserts.In general,satellite IoT networks take low Earth orbit(LEO)satellites as access points,which solves the problem of wide coverage,but leads to many challenging issues.We first give an overview of satellite IoT,with an emphasis on revealing the characteristics of IoT services.Then,the challenging issues of satellite IoT,i.e.,massive connectivity,wide coverage,high mobility,low power,and stringent delay,are analyzed in detail.Furthermore,the possible solutions to these challenges are provided.In particular,new massive access protocols and techniques are designed according to the characteristics and requirements of satellite IoT.Finally,we discuss several development trends of satellite IoT to stimulate and encourage further research in such a broad area.展开更多
Accurate prediction of the temporal and spatial characteristics of COVID-19 infection is of paramount importance for effective epidemic prevention and control.In order to accomplish this objective,we incorporated indi...Accurate prediction of the temporal and spatial characteristics of COVID-19 infection is of paramount importance for effective epidemic prevention and control.In order to accomplish this objective,we incorporated individual antibody dynamics into an agent-based model and devised a methodology that encompasses the dynamic behaviors of each individual,thereby explicitly capturing the count and spatial distribution of infected individuals with varying symptoms at distinct time points.Our model also permits the evaluation of diverse prevention and control measures.Based on our findings,the widespread employment of nucleic acid testing and the implementation of quarantine measures for positive cases and their close contacts in China have yielded remarkable outcomes in curtailing a less transmissible yet more virulent strain;however,they may prove inadequate against highly transmissible and less virulent variants.Additionally,our model excels in its ability to trace back to the initial infected case(patient zero)through early epidemic patterns.Ultimately,our model extends the frontiers of traditional epidemiological simulation methodologies and offers an alternative approach to epidemic modeling.展开更多
基金Project supported by the National Natural Science Foundation of China(No.U21A20443)。
文摘Satellite Internet of Things(IoT)is a promising way to provide seamless coverage to a massive number of devices all over the world,especially in remote areas not covered by cellular networks,e.g.,forests,oceans,mountains,and deserts.In general,satellite IoT networks take low Earth orbit(LEO)satellites as access points,which solves the problem of wide coverage,but leads to many challenging issues.We first give an overview of satellite IoT,with an emphasis on revealing the characteristics of IoT services.Then,the challenging issues of satellite IoT,i.e.,massive connectivity,wide coverage,high mobility,low power,and stringent delay,are analyzed in detail.Furthermore,the possible solutions to these challenges are provided.In particular,new massive access protocols and techniques are designed according to the characteristics and requirements of satellite IoT.Finally,we discuss several development trends of satellite IoT to stimulate and encourage further research in such a broad area.
基金funded by DeZhou University,grant number 30101418.
文摘Accurate prediction of the temporal and spatial characteristics of COVID-19 infection is of paramount importance for effective epidemic prevention and control.In order to accomplish this objective,we incorporated individual antibody dynamics into an agent-based model and devised a methodology that encompasses the dynamic behaviors of each individual,thereby explicitly capturing the count and spatial distribution of infected individuals with varying symptoms at distinct time points.Our model also permits the evaluation of diverse prevention and control measures.Based on our findings,the widespread employment of nucleic acid testing and the implementation of quarantine measures for positive cases and their close contacts in China have yielded remarkable outcomes in curtailing a less transmissible yet more virulent strain;however,they may prove inadequate against highly transmissible and less virulent variants.Additionally,our model excels in its ability to trace back to the initial infected case(patient zero)through early epidemic patterns.Ultimately,our model extends the frontiers of traditional epidemiological simulation methodologies and offers an alternative approach to epidemic modeling.