Kuo,Yeh-Tzu founded Taiwan’s Sung Shan Tsu Huei Temple in 1970.She organized more than 200 worshipers as a group named“Taiwan Tsu Huei Temple Queen Mother of the West Delegation to China to Worship at the Ancestral ...Kuo,Yeh-Tzu founded Taiwan’s Sung Shan Tsu Huei Temple in 1970.She organized more than 200 worshipers as a group named“Taiwan Tsu Huei Temple Queen Mother of the West Delegation to China to Worship at the Ancestral Temples”in 1990.At that time,the temple building of the Queen Mother Palace in Huishan of Gansu Province was in disrepair,and Temple Master Kuo,Yeh-Tzu made a vow to rebuild it.Rebuilding the ancestral temple began in 1992 and was completed in 1994.It was the first case of a Taiwan temple financing the rebuilding of a far-away Queen Mother Palace with its own donations.In addition,Sung Shan Tsu Huei Temple celebrated its 45th anniversary and hosted Yiwei Yuanheng Lizhen Daluo Tiandi Qingjiao(Momentous and Fortuitous Heaven and Earth Prayer Ceremony)in 2015.This is the most important and the grandest blessing ceremony of Taoism,a rare event for Taoism locally and abroad during this century.Those sacred rituals were replete with unprecedented grand wishes to propagate the belief in Queen Mother of the West.Stopping at nothing,Queen Mother’s love never ceases.展开更多
Delay/Disruption-Tolerant Networking(DTN) originated from research on Interplanetary Internet and still today space applications are the most important application field and research stimulus. This paper investigates ...Delay/Disruption-Tolerant Networking(DTN) originated from research on Interplanetary Internet and still today space applications are the most important application field and research stimulus. This paper investigates DTN communications between the Earth and the far side of the Moon, by means of a lunar orbiter acting as relay. After an introductory part, the paper presents a comprehensive analysis of the DTN performance that can be achieved on the identified communication scenario. The focus is on the evaluation of the stateof-the-art ability of Interplanetary Overlay Network(ION), the NASA DTN implementation of Bundle Protocol(BP) and Contact Graph Routing(CGR), to meet the many challenges of the space communication scenario investigated(and more generally of a future interplaynetary Internet): intermittent links, network partitioning, scarce bandwidth, long delays, dynamic routing, handling of high priority and emergency traffic, interoperability issues. A study of security threats and Bundle Security Protocol(BSP) countermeasures complete the work.The many results provided, confirm the essential role of DTN in future space communications.展开更多
The numbers of beam positions(BPs)and time slots for beam hopping(BH)dominate the latency of LEO satellite communications.Aiming at minimizing the number of BPs subject to a predefined requirement on the radius of BP,...The numbers of beam positions(BPs)and time slots for beam hopping(BH)dominate the latency of LEO satellite communications.Aiming at minimizing the number of BPs subject to a predefined requirement on the radius of BP,a low-complexity user density-based BP design scheme is proposed,where the original problem is decomposed into two subproblems,with the first one to find the sparsest user and the second one to determine the corresponding best BP.In particular,for the second subproblem,a user selection and smallest BP radius algorithm is proposed,where the nearby users are sequentially selected until the constraint of the given BP radius is no longer satisfied.These two subproblems are iteratively solved until all the users are selected.To further reduce the BP radius,a duplicated user removal algorithm is proposed to decrease the number of the users covered by two or more BPs.Aiming at minimizing the number of time slots subject to the no co-channel interference(CCI)constraint and the traffic demand constraint,a low-complexity CCI-free BH design scheme is proposed,where the BPs having difficulty in satisfying the constraints are considered to be illuminated in priory.Simulation results verify the effectiveness of the proposed schemes.展开更多
Hourly outgoing longwave radiation (OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite (COMS) has been retrieved since June 2010.The COMS OLR retrieval algorithms are based o...Hourly outgoing longwave radiation (OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite (COMS) has been retrieved since June 2010.The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels.This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm (OLR12.0 using the 12.0 μm channel) and three multiple-channel algorithms (OLR10.8+12.0 using the 10.8 and 12.0 pm channels; OLR6.7+10.8 using the 6.7 and 10.8 μm channels; and OLRAll using the 6.7,10.8,and 12.0 μm channels).The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System (CERES) over the full COMS field of view [roughly (50°S-50°N,70°-170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5-7 W m-2,which indicates good agreement with CERES OLR over the vast domain.OLR6.7+10.8 and OLRAll have much smaller errors (~ 6 W m-2) than OLR12.0 and OLR10.8+12.0 (~ 8 W m-2).Moreover,the small errors of OLR6.7+10.8 and OLRAll are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration.These results indicate a noteworthy role of the 6.7 μm water vapor absorption channel in improving the accuracy of the OLRs.The dependence of the accuracy of COMS OLRs on various surface,atmospheric,and observational conditions is also discussed.展开更多
Multiple earth observing satellites need to communicate with each other to observe plenty of targets on the Earth together. The factors, such as external interference, result in satellite information interaction delay...Multiple earth observing satellites need to communicate with each other to observe plenty of targets on the Earth together. The factors, such as external interference, result in satellite information interaction delays, which is unable to ensure the integrity and timeliness of the information on decision making for satellites. And the optimization of the planning result is affected. Therefore, the effect of communication delay is considered during the multi-satel ite coordinating process. For this problem, firstly, a distributed cooperative optimization problem for multiple satellites in the delayed communication environment is formulized. Secondly, based on both the analysis of the temporal sequence of tasks in a single satellite and the dynamically decoupled characteristics of the multi-satellite system, the environment information of multi-satellite distributed cooperative optimization is constructed on the basis of the directed acyclic graph(DAG). Then, both a cooperative optimization decision making framework and a model are built according to the decentralized partial observable Markov decision process(DEC-POMDP). After that, a satellite coordinating strategy aimed at different conditions of communication delay is mainly analyzed, and a unified processing strategy on communication delay is designed. An approximate cooperative optimization algorithm based on simulated annealing is proposed. Finally, the effectiveness and robustness of the method presented in this paper are verified via the simulation.展开更多
A satellite communication system consisting of small earth terminals which utilize spread spectrum multiple access (SSMA) techniques is introduced in this paper. Having no master station, the system is distributively ...A satellite communication system consisting of small earth terminals which utilize spread spectrum multiple access (SSMA) techniques is introduced in this paper. Having no master station, the system is distributively controlled. The frequency band used is 6/4GHz.展开更多
This paper discusses the significance and prospects of low altitude small satellite aerial vehicles to ensure smooth aerial-ground communications for next-generation broadband networks.To achieve the generic goals of ...This paper discusses the significance and prospects of low altitude small satellite aerial vehicles to ensure smooth aerial-ground communications for next-generation broadband networks.To achieve the generic goals of fifthgeneration and beyondwireless networks,the existing aerial network architecture needs to be revisited.The detailed architecture of low altitude aerial networks and the challenges in resource management have been illustrated in this paper.Moreover,we have studied the coordination between promising communication technologies and low altitude aerial networks to provide robust network coverage.We talk about the techniques that can ensure userfriendly control and monitoring of the low altitude aerial networks to bring forth wireless broadband connectivity to a new dimension.In the end,we highlight the future research directions of aerial-ground communications in terms of access technologies,machine learning,compressed sensing,and quantum communications.展开更多
THIS photograph was published in the book, A Century of Historical Chinese Photographs, with only a one-line caption: "A private school for Christian girls opened by the foreign Mission of the Virgin Mary in Shan...THIS photograph was published in the book, A Century of Historical Chinese Photographs, with only a one-line caption: "A private school for Christian girls opened by the foreign Mission of the Virgin Mary in Shanghai." Determining which country’s church, which year it opened, and what kind of a private girls’ school it was would be nearly impossible. But this should not stop展开更多
文摘Kuo,Yeh-Tzu founded Taiwan’s Sung Shan Tsu Huei Temple in 1970.She organized more than 200 worshipers as a group named“Taiwan Tsu Huei Temple Queen Mother of the West Delegation to China to Worship at the Ancestral Temples”in 1990.At that time,the temple building of the Queen Mother Palace in Huishan of Gansu Province was in disrepair,and Temple Master Kuo,Yeh-Tzu made a vow to rebuild it.Rebuilding the ancestral temple began in 1992 and was completed in 1994.It was the first case of a Taiwan temple financing the rebuilding of a far-away Queen Mother Palace with its own donations.In addition,Sung Shan Tsu Huei Temple celebrated its 45th anniversary and hosted Yiwei Yuanheng Lizhen Daluo Tiandi Qingjiao(Momentous and Fortuitous Heaven and Earth Prayer Ceremony)in 2015.This is the most important and the grandest blessing ceremony of Taoism,a rare event for Taoism locally and abroad during this century.Those sacred rituals were replete with unprecedented grand wishes to propagate the belief in Queen Mother of the West.Stopping at nothing,Queen Mother’s love never ceases.
文摘Delay/Disruption-Tolerant Networking(DTN) originated from research on Interplanetary Internet and still today space applications are the most important application field and research stimulus. This paper investigates DTN communications between the Earth and the far side of the Moon, by means of a lunar orbiter acting as relay. After an introductory part, the paper presents a comprehensive analysis of the DTN performance that can be achieved on the identified communication scenario. The focus is on the evaluation of the stateof-the-art ability of Interplanetary Overlay Network(ION), the NASA DTN implementation of Bundle Protocol(BP) and Contact Graph Routing(CGR), to meet the many challenges of the space communication scenario investigated(and more generally of a future interplaynetary Internet): intermittent links, network partitioning, scarce bandwidth, long delays, dynamic routing, handling of high priority and emergency traffic, interoperability issues. A study of security threats and Bundle Security Protocol(BSP) countermeasures complete the work.The many results provided, confirm the essential role of DTN in future space communications.
基金supported in part by National Key Research and Development Program of China under Grant 2021YFB2900404。
文摘The numbers of beam positions(BPs)and time slots for beam hopping(BH)dominate the latency of LEO satellite communications.Aiming at minimizing the number of BPs subject to a predefined requirement on the radius of BP,a low-complexity user density-based BP design scheme is proposed,where the original problem is decomposed into two subproblems,with the first one to find the sparsest user and the second one to determine the corresponding best BP.In particular,for the second subproblem,a user selection and smallest BP radius algorithm is proposed,where the nearby users are sequentially selected until the constraint of the given BP radius is no longer satisfied.These two subproblems are iteratively solved until all the users are selected.To further reduce the BP radius,a duplicated user removal algorithm is proposed to decrease the number of the users covered by two or more BPs.Aiming at minimizing the number of time slots subject to the no co-channel interference(CCI)constraint and the traffic demand constraint,a low-complexity CCI-free BH design scheme is proposed,where the BPs having difficulty in satisfying the constraints are considered to be illuminated in priory.Simulation results verify the effectiveness of the proposed schemes.
基金supported by the Korea Meteorological Administration Research and Development Program (Grant No. CATER 2012-2040)
文摘Hourly outgoing longwave radiation (OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite (COMS) has been retrieved since June 2010.The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels.This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm (OLR12.0 using the 12.0 μm channel) and three multiple-channel algorithms (OLR10.8+12.0 using the 10.8 and 12.0 pm channels; OLR6.7+10.8 using the 6.7 and 10.8 μm channels; and OLRAll using the 6.7,10.8,and 12.0 μm channels).The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System (CERES) over the full COMS field of view [roughly (50°S-50°N,70°-170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5-7 W m-2,which indicates good agreement with CERES OLR over the vast domain.OLR6.7+10.8 and OLRAll have much smaller errors (~ 6 W m-2) than OLR12.0 and OLR10.8+12.0 (~ 8 W m-2).Moreover,the small errors of OLR6.7+10.8 and OLRAll are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration.These results indicate a noteworthy role of the 6.7 μm water vapor absorption channel in improving the accuracy of the OLRs.The dependence of the accuracy of COMS OLRs on various surface,atmospheric,and observational conditions is also discussed.
基金supported by the National Science Foundation for Young Scholars of China(6130123471401175)
文摘Multiple earth observing satellites need to communicate with each other to observe plenty of targets on the Earth together. The factors, such as external interference, result in satellite information interaction delays, which is unable to ensure the integrity and timeliness of the information on decision making for satellites. And the optimization of the planning result is affected. Therefore, the effect of communication delay is considered during the multi-satel ite coordinating process. For this problem, firstly, a distributed cooperative optimization problem for multiple satellites in the delayed communication environment is formulized. Secondly, based on both the analysis of the temporal sequence of tasks in a single satellite and the dynamically decoupled characteristics of the multi-satellite system, the environment information of multi-satellite distributed cooperative optimization is constructed on the basis of the directed acyclic graph(DAG). Then, both a cooperative optimization decision making framework and a model are built according to the decentralized partial observable Markov decision process(DEC-POMDP). After that, a satellite coordinating strategy aimed at different conditions of communication delay is mainly analyzed, and a unified processing strategy on communication delay is designed. An approximate cooperative optimization algorithm based on simulated annealing is proposed. Finally, the effectiveness and robustness of the method presented in this paper are verified via the simulation.
文摘A satellite communication system consisting of small earth terminals which utilize spread spectrum multiple access (SSMA) techniques is introduced in this paper. Having no master station, the system is distributively controlled. The frequency band used is 6/4GHz.
文摘This paper discusses the significance and prospects of low altitude small satellite aerial vehicles to ensure smooth aerial-ground communications for next-generation broadband networks.To achieve the generic goals of fifthgeneration and beyondwireless networks,the existing aerial network architecture needs to be revisited.The detailed architecture of low altitude aerial networks and the challenges in resource management have been illustrated in this paper.Moreover,we have studied the coordination between promising communication technologies and low altitude aerial networks to provide robust network coverage.We talk about the techniques that can ensure userfriendly control and monitoring of the low altitude aerial networks to bring forth wireless broadband connectivity to a new dimension.In the end,we highlight the future research directions of aerial-ground communications in terms of access technologies,machine learning,compressed sensing,and quantum communications.
文摘THIS photograph was published in the book, A Century of Historical Chinese Photographs, with only a one-line caption: "A private school for Christian girls opened by the foreign Mission of the Virgin Mary in Shanghai." Determining which country’s church, which year it opened, and what kind of a private girls’ school it was would be nearly impossible. But this should not stop