This paper proposes an adaptive joint source and channel coding scheme for H.264 video multicast over wireless LAN which takes into account the user topology changes and varying channel conditions of multiple users, a...This paper proposes an adaptive joint source and channel coding scheme for H.264 video multicast over wireless LAN which takes into account the user topology changes and varying channel conditions of multiple users, and dynamically allocates available bandwidth between source coding and channel coding, with the goal to optimize the overall system performance. In particular, source resilience and error correction are considered jointly in the scheme to achieve the optimal performance. And a channel estimation algorithm based on the average packet loss rate and the variance of packet loss rate is proposed also. Two overall performance criteria for video multicast are investigated and experimental results are presented to show the improvement obtained by the scheme.展开更多
From March 7th to 11th,2022,the 40th CERAWeek,known as the“Davos Forum”of the energy sector,was held in Houston,USA,the energy capital of the world.This was the first offline CERAWeek since the outbreak of the COVID...From March 7th to 11th,2022,the 40th CERAWeek,known as the“Davos Forum”of the energy sector,was held in Houston,USA,the energy capital of the world.This was the first offline CERAWeek since the outbreak of the COVID-19 pandemic and the first CERAWeek with S&P Global as the organizer.展开更多
2022 will be a turning point for green hydrogen Clearer policies will continue to drive the construction of pipelines for green hydrogen(and related products).Projects proposed in 2021 have an electrolysis capacity cl...2022 will be a turning point for green hydrogen Clearer policies will continue to drive the construction of pipelines for green hydrogen(and related products).Projects proposed in 2021 have an electrolysis capacity close to 250GW,compared with 70GW in 2020 and less than 15GW in 2019,said Paola Perez-Pe?a,Principal Researcher at S&P Global.展开更多
Chinese watchtower houses are part of the unique human cultural heritage of the world’s vernacular architectures.Many earthen manor watchtower houses in Chongqing,China,have absorbed the characteristics of other towe...Chinese watchtower houses are part of the unique human cultural heritage of the world’s vernacular architectures.Many earthen manor watchtower houses in Chongqing,China,have absorbed the characteristics of other tower houses across the country and have brought together various types of watchtower construction techniques.They are important connection points for the integrity of the Chinese watchtower house as a comprehensive architectural cultural heritage system.They can be a typical sample of Chinese Han classical towers.These buildings are indispensable parts of the Chinese residential watchtower system and have important cultural protection value.However,due to the general lack of excavation and attention to their historical and cultural value,these buildings are on the verge of disappearing.Although they have lost their original architectural functions,they have important value in terms of their building materials,technical composition and artistic modelling.They can stimulate special emotional resonance and become an important bridge that maintains the cultural connection between ancient and modern humans.Therefore,discussing the historical and cultural value of Chongqing rammed earth watchtower houses,the strategy for heritage protection and utilisation is of far-reaching signifcance for Chinese watchtower dwellings.展开更多
文摘This paper proposes an adaptive joint source and channel coding scheme for H.264 video multicast over wireless LAN which takes into account the user topology changes and varying channel conditions of multiple users, and dynamically allocates available bandwidth between source coding and channel coding, with the goal to optimize the overall system performance. In particular, source resilience and error correction are considered jointly in the scheme to achieve the optimal performance. And a channel estimation algorithm based on the average packet loss rate and the variance of packet loss rate is proposed also. Two overall performance criteria for video multicast are investigated and experimental results are presented to show the improvement obtained by the scheme.
文摘From March 7th to 11th,2022,the 40th CERAWeek,known as the“Davos Forum”of the energy sector,was held in Houston,USA,the energy capital of the world.This was the first offline CERAWeek since the outbreak of the COVID-19 pandemic and the first CERAWeek with S&P Global as the organizer.
文摘2022 will be a turning point for green hydrogen Clearer policies will continue to drive the construction of pipelines for green hydrogen(and related products).Projects proposed in 2021 have an electrolysis capacity close to 250GW,compared with 70GW in 2020 and less than 15GW in 2019,said Paola Perez-Pe?a,Principal Researcher at S&P Global.
基金Sichuan Fine Arts Insititute Doctoral Research Program‘Chongqing Bayu Watch Tower House Construction Art History and Culture Tracing and Application Research’(2018BSBY016)Chongqing Art Science Research Planning Project‘Study on collage protection strategy of architectural cultural heritage of endangered rammed earth blockhouses in Bayu’(21ZD04)。
文摘Chinese watchtower houses are part of the unique human cultural heritage of the world’s vernacular architectures.Many earthen manor watchtower houses in Chongqing,China,have absorbed the characteristics of other tower houses across the country and have brought together various types of watchtower construction techniques.They are important connection points for the integrity of the Chinese watchtower house as a comprehensive architectural cultural heritage system.They can be a typical sample of Chinese Han classical towers.These buildings are indispensable parts of the Chinese residential watchtower system and have important cultural protection value.However,due to the general lack of excavation and attention to their historical and cultural value,these buildings are on the verge of disappearing.Although they have lost their original architectural functions,they have important value in terms of their building materials,technical composition and artistic modelling.They can stimulate special emotional resonance and become an important bridge that maintains the cultural connection between ancient and modern humans.Therefore,discussing the historical and cultural value of Chongqing rammed earth watchtower houses,the strategy for heritage protection and utilisation is of far-reaching signifcance for Chinese watchtower dwellings.
