Low-earth-orbit(LEO)satellite network has become a critical component of the satelliteterrestrial integrated network(STIN)due to its superior signal quality and minimal communication latency.However,the highly dynamic...Low-earth-orbit(LEO)satellite network has become a critical component of the satelliteterrestrial integrated network(STIN)due to its superior signal quality and minimal communication latency.However,the highly dynamic nature of LEO satellites leads to limited and rapidly varying contact time between them and Earth stations(ESs),making it difficult to timely download massive communication and remote sensing data within the limited time window.To address this challenge in heterogeneous satellite networks with coexisting geostationary-earth-orbit(GEO)and LEO satellites,this paper proposes a dynamic collaborative inter-satellite data download strategy to optimize the long-term weighted energy consumption and data downloads within the constraints of on-board power,backlog stability and time-varying contact.Specifically,the Lyapunov optimization theory is applied to transform the long-term stochastic optimization problem,subject to time-varying contact time and on-board power constraints,into multiple deterministic single time slot problems,based on which online distributed algorithms are developed to enable each satellite to independently obtain the transmit power allocation and data processing decisions in closed-form.Finally,the simulation results demonstrate the superiority of the proposed scheme over benchmarks,e.g.,achieving asymptotic optimality of the weighted energy consumption and data downloads,while maintaining stability of the on-board backlog.展开更多
Downloads of national standards exceed 10 million times in the first half of 2025 In response to social needs,State Administration for Market Regulation(SAMR)had steadily promoted the full-text disclosure and free dow...Downloads of national standards exceed 10 million times in the first half of 2025 In response to social needs,State Administration for Market Regulation(SAMR)had steadily promoted the full-text disclosure and free download of over 30,000 national standards that do not adopt international standards since the beginning of this year.In the first half of 2025,downloads exceeded 10 million times,providing strong support for the construction of a unified national market.Social groups accessing national standards for free increased significantly.In the first half of this year,the average monthly downloads of national standards surged tenfold from 190,000 times last year to 2.03 million times.Online reading reached nearly 15 million times,and page views hit 89 million times.The disclosure of national standards for free has effectively broken information barriers in standards,ensuring equal rights for business entities to read and download national standards.展开更多
Acta Geologica Sinica(English Edition)is a bimonthly,SCI-indexed academic journal produced by the Geological Society of China.With the latest 2023 Impact Factor of 2.1,it has long been indexed by many international da...Acta Geologica Sinica(English Edition)is a bimonthly,SCI-indexed academic journal produced by the Geological Society of China.With the latest 2023 Impact Factor of 2.1,it has long been indexed by many international databases and websites,such as SCI,CA,BIG,etc.Internationally,the journal cooperates with John Wiley&Sons,Inc.to publish the electronic version;all papers can be downloaded online.Contributors wishing to submit,read,enquire and download can log in via http://mc.manuscriptcentral.com/ags.展开更多
The recent advances in wireless communication technology enable high-speed vehicles to download data from roadside units(RSUs). However, the data download volume of individual vehicle is rather restricted due to high ...The recent advances in wireless communication technology enable high-speed vehicles to download data from roadside units(RSUs). However, the data download volume of individual vehicle is rather restricted due to high mobility and limited transmission range of vehicles, bringing users poor performance. To address this issue, we exploit the combination of both clustering and carry-and-forward schemes in this paper. Our scheme coordinates the cooperation of multiple infrastructures, cluster formation in the same direction and data forwarding of reverse vehicles to facilitate the target vehicle to download large-size content in dark areas. The process of data dissemination and achievable data download volume are then derived and analyzed theoretically. Finally, we conduct extensive simulations to verify the performance of the proposed scheme. Results show significant benefits of the proposed scheme in terms of increasing data download volume and throughput.展开更多
P4M(Positive Pulser Pulse Position Modulation)码是将测量数据信息利用脉冲信号之间的间隔时间的大小来表达的一种传输方式。主要从仪器的整个传输过程入手,仪器是如何把Sensor测量数据转化成脉冲信号,如何把接收的脉冲信号转化为Sen...P4M(Positive Pulser Pulse Position Modulation)码是将测量数据信息利用脉冲信号之间的间隔时间的大小来表达的一种传输方式。主要从仪器的整个传输过程入手,仪器是如何把Sensor测量数据转化成脉冲信号,如何把接收的脉冲信号转化为Sensor测量数据值,它们使用什么样的运算法则,以及怎样去通过DOWNLOAD菜单控制这个过程,及DOWNLOAD菜单的某些参数是如何设置的。展开更多
With the effort of all Editorial Board members and reviewers of the Virologica Sinica(VS),the journal got great progress in the year 2015.VS has been newly indexed by SCIE and the yearly download times on Springerlink...With the effort of all Editorial Board members and reviewers of the Virologica Sinica(VS),the journal got great progress in the year 2015.VS has been newly indexed by SCIE and the yearly download times on Springerlink have reached the highest record in its history.The Editors of the Virologica Sinica would like to thank all the following reviewers for their excellent work for展开更多
Communication is important for providing intelligent services in connected vehicles.Vehicles must be able to communicate with different places and exchange information while driving.For service operation,connected veh...Communication is important for providing intelligent services in connected vehicles.Vehicles must be able to communicate with different places and exchange information while driving.For service operation,connected vehicles frequently attempt to download large amounts of data.They can request data downloading to a road side unit(RSU),which provides infrastructure for connected vehicles.The RSU is a data bottleneck in a transportation system because data traffic is concentrated on the RSU.Therefore,it is not appropriate for a connected vehicle to always attempt a high speed download from the RSU.If the mobile network between a connected vehicle and an RSU has poor connection quality,the efficiency and speed of the data download from the RSU is decreased.This problem affects the quality of the user experience.Therefore,it is important for a connected vehicle to connect to an RSU with consideration of the network conditions in order to try to maximize download speed.The proposed method maximizes download speed from an RSU using a machine learning algorithm.To collect and learn from network data,fog computing is used.A fog server is integrated with the RSU to perform computing.If the algorithm recognizes that conditions are not good for mass data download,it will not attempt to download at high speed.Thus,the proposed method can improve the efficiency of high speed downloads.This conclusion was validated using extensive computer simulations.展开更多
Manuscript should be submitted in word format through the website http://journals-myco.im.ac.cn or by email to jwxt@im.ac.cn. The template of manuscript can be downloaded from the website homepage. There is no firmly ...Manuscript should be submitted in word format through the website http://journals-myco.im.ac.cn or by email to jwxt@im.ac.cn. The template of manuscript can be downloaded from the website homepage. There is no firmly established length, but entire paper (ineluding tables and figures) exceeding 20 pages is discouraged.展开更多
Manuscript should be submitted in word format through the website http://journals-myco.im.ac.cn or by email to wxt@im.ac.cn.The template of manuscript can be downloaded from the website homepage.
Manuscript should be submitted in word format through the website htp://journals-myco.im.ac.cn or by email to jwxt@im.ac.cn.The template of manuscript can be downloaded from the website homepage.There is no firmly est...Manuscript should be submitted in word format through the website htp://journals-myco.im.ac.cn or by email to jwxt@im.ac.cn.The template of manuscript can be downloaded from the website homepage.There is no firmly established length,but entire paper(including tables and figures)exceeding 20 pages is discouraged.展开更多
In May 2008, ScienceWatch.com named Advances in Atmospheric Sciences a Rising Star among Geosciences journals. According to Essential Science IndicatorsSM from Thomson Reuters, the journal＇s cur-rent citation record ...In May 2008, ScienceWatch.com named Advances in Atmospheric Sciences a Rising Star among Geosciences journals. According to Essential Science IndicatorsSM from Thomson Reuters, the journal＇s cur-rent citation record includes 764 papers cited a total of 1,658 times between January 1, 1998 and February 29 2008.展开更多
基金supported by the National Natural Science Foundation of China under Grant 62371098the National Key Laboratory ofWireless Communications Foundation under Grant IFN20230203the National Key Research and Development Program of China under Grant 2021YFB2900404.
文摘Low-earth-orbit(LEO)satellite network has become a critical component of the satelliteterrestrial integrated network(STIN)due to its superior signal quality and minimal communication latency.However,the highly dynamic nature of LEO satellites leads to limited and rapidly varying contact time between them and Earth stations(ESs),making it difficult to timely download massive communication and remote sensing data within the limited time window.To address this challenge in heterogeneous satellite networks with coexisting geostationary-earth-orbit(GEO)and LEO satellites,this paper proposes a dynamic collaborative inter-satellite data download strategy to optimize the long-term weighted energy consumption and data downloads within the constraints of on-board power,backlog stability and time-varying contact.Specifically,the Lyapunov optimization theory is applied to transform the long-term stochastic optimization problem,subject to time-varying contact time and on-board power constraints,into multiple deterministic single time slot problems,based on which online distributed algorithms are developed to enable each satellite to independently obtain the transmit power allocation and data processing decisions in closed-form.Finally,the simulation results demonstrate the superiority of the proposed scheme over benchmarks,e.g.,achieving asymptotic optimality of the weighted energy consumption and data downloads,while maintaining stability of the on-board backlog.
文摘Downloads of national standards exceed 10 million times in the first half of 2025 In response to social needs,State Administration for Market Regulation(SAMR)had steadily promoted the full-text disclosure and free download of over 30,000 national standards that do not adopt international standards since the beginning of this year.In the first half of 2025,downloads exceeded 10 million times,providing strong support for the construction of a unified national market.Social groups accessing national standards for free increased significantly.In the first half of this year,the average monthly downloads of national standards surged tenfold from 190,000 times last year to 2.03 million times.Online reading reached nearly 15 million times,and page views hit 89 million times.The disclosure of national standards for free has effectively broken information barriers in standards,ensuring equal rights for business entities to read and download national standards.
文摘Acta Geologica Sinica(English Edition)is a bimonthly,SCI-indexed academic journal produced by the Geological Society of China.With the latest 2023 Impact Factor of 2.1,it has long been indexed by many international databases and websites,such as SCI,CA,BIG,etc.Internationally,the journal cooperates with John Wiley&Sons,Inc.to publish the electronic version;all papers can be downloaded online.Contributors wishing to submit,read,enquire and download can log in via http://mc.manuscriptcentral.com/ags.
基金supported by the National Natural Science Foundation of China under Grant No.61571350Key Research and Development Program of Shaanxi(Contract No.2017KW-004,2017ZDXM-GY-022)the 111 Project(B08038)
文摘The recent advances in wireless communication technology enable high-speed vehicles to download data from roadside units(RSUs). However, the data download volume of individual vehicle is rather restricted due to high mobility and limited transmission range of vehicles, bringing users poor performance. To address this issue, we exploit the combination of both clustering and carry-and-forward schemes in this paper. Our scheme coordinates the cooperation of multiple infrastructures, cluster formation in the same direction and data forwarding of reverse vehicles to facilitate the target vehicle to download large-size content in dark areas. The process of data dissemination and achievable data download volume are then derived and analyzed theoretically. Finally, we conduct extensive simulations to verify the performance of the proposed scheme. Results show significant benefits of the proposed scheme in terms of increasing data download volume and throughput.
文摘P4M(Positive Pulser Pulse Position Modulation)码是将测量数据信息利用脉冲信号之间的间隔时间的大小来表达的一种传输方式。主要从仪器的整个传输过程入手,仪器是如何把Sensor测量数据转化成脉冲信号,如何把接收的脉冲信号转化为Sensor测量数据值,它们使用什么样的运算法则,以及怎样去通过DOWNLOAD菜单控制这个过程,及DOWNLOAD菜单的某些参数是如何设置的。
文摘With the effort of all Editorial Board members and reviewers of the Virologica Sinica(VS),the journal got great progress in the year 2015.VS has been newly indexed by SCIE and the yearly download times on Springerlink have reached the highest record in its history.The Editors of the Virologica Sinica would like to thank all the following reviewers for their excellent work for
文摘Communication is important for providing intelligent services in connected vehicles.Vehicles must be able to communicate with different places and exchange information while driving.For service operation,connected vehicles frequently attempt to download large amounts of data.They can request data downloading to a road side unit(RSU),which provides infrastructure for connected vehicles.The RSU is a data bottleneck in a transportation system because data traffic is concentrated on the RSU.Therefore,it is not appropriate for a connected vehicle to always attempt a high speed download from the RSU.If the mobile network between a connected vehicle and an RSU has poor connection quality,the efficiency and speed of the data download from the RSU is decreased.This problem affects the quality of the user experience.Therefore,it is important for a connected vehicle to connect to an RSU with consideration of the network conditions in order to try to maximize download speed.The proposed method maximizes download speed from an RSU using a machine learning algorithm.To collect and learn from network data,fog computing is used.A fog server is integrated with the RSU to perform computing.If the algorithm recognizes that conditions are not good for mass data download,it will not attempt to download at high speed.Thus,the proposed method can improve the efficiency of high speed downloads.This conclusion was validated using extensive computer simulations.
文摘Manuscript should be submitted in word format through the website http://journals-myco.im.ac.cn or by email to jwxt@im.ac.cn. The template of manuscript can be downloaded from the website homepage. There is no firmly established length, but entire paper (ineluding tables and figures) exceeding 20 pages is discouraged.
文摘Manuscript should be submitted in word format through the website http://journals-myco.im.ac.cn or by email to wxt@im.ac.cn.The template of manuscript can be downloaded from the website homepage.
文摘Manuscript should be submitted in word format through the website htp://journals-myco.im.ac.cn or by email to jwxt@im.ac.cn.The template of manuscript can be downloaded from the website homepage.There is no firmly established length,but entire paper(including tables and figures)exceeding 20 pages is discouraged.
文摘In May 2008, ScienceWatch.com named Advances in Atmospheric Sciences a Rising Star among Geosciences journals. According to Essential Science IndicatorsSM from Thomson Reuters, the journal＇s cur-rent citation record includes 764 papers cited a total of 1,658 times between January 1, 1998 and February 29 2008.
