Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems...Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.展开更多
Hydrogen can serve as a carrier to store renewable energy in large scale.However,hydrogen storage still remains a challenge in the current stage.It is difficult to meet the technical requirements applying the conventi...Hydrogen can serve as a carrier to store renewable energy in large scale.However,hydrogen storage still remains a challenge in the current stage.It is difficult to meet the technical requirements applying the conventional storage of compressed gaseous hydrogen in high-pressure tanks or the solid-state storage of hydrogen in suitable materials.In the present work,a gaseous and solid-state(G-S)hybrid hydrogen storage system with a low working pressure below 5 MPa for a 10 kW hydrogen energy storage experiment platform is developed and validated.A Ti-Mn type hydrogen storage alloy with an effective hydrogen capacity of 1.7 wt%was prepared for the G-S hybrid hydrogen storage system.The G-S hybrid hydrogen storage tank has a high volumetric hydrogen storage density of 40.07 kg H_(2)m^(-3) and stores hydrogen under pressure below5 MPa.It can readily release enough hydrogen at a temperature as low as-15C when the FC system is not fully activated and hot water is not available.The energy storage efficiency of this G-S hybrid hydrogen storage system is calculated to be 86.4%-95.9%when it is combined with an FC system.This work provides a method on how to design a G-S hydrogen storage system based on practical demands and demonstrates that the G-S hybrid hydrogen storage is a promising method for stationary hydrogen storage application.展开更多
The modern instrument manufacturing has many features, such as high technologies, multiple varieties and small quantities. Aiming at those features, an instrumentation flexible developing system （IFDS） is presented....The modern instrument manufacturing has many features, such as high technologies, multiple varieties and small quantities. Aiming at those features, an instrumentation flexible developing system （IFDS） is presented. It constitutes a kind of opening, compatible, extensible and upgradeable flexible developing system, and it will offer a kind of technology equipment for the research and development of new modern instrument products. Its flexible mechanism is able to be suited for different and special requirements of many instrument systems, and its system integrated mechanism is able to adapt to common technological features of most instrument systems. It is IFDS that makes it easy to accomplish a quick system integration of instrument products. IFDS solves key technological problems related to modern instruments development, develops multiple systems for modern instrument development and accomplishes rapid development of series of new products.展开更多
Few of the current approaches to achieve the integration of digital library system have considered the influence of network factors on quality of service for the integration system of digital libraries. For this reaso...Few of the current approaches to achieve the integration of digital library system have considered the influence of network factors on quality of service for the integration system of digital libraries. For this reason, a mobile agent based framework for integrating digital library system is proposed. Based on this framework, a prototype system is implemented and the key technique for it are described. Compared with the current approaches, using mobile agent technique to achieve the integration of digital library system can not only avoid transmitting a lot of data on the network, lower the dependence on network bandwidth for the system, but also improve the quality of service for the integration system of digital libraries in intermitted or unreliable network connection settings.展开更多
The causes and the problems of integration of scientific ＆ technical innovation （ISTI） and inevitability are proposed. The status of domestic scientific ＆ technical innovation is analysed. A series of emergent man...The causes and the problems of integration of scientific ＆ technical innovation （ISTI） and inevitability are proposed. The status of domestic scientific ＆ technical innovation is analysed. A series of emergent managerial problems caused by the system ISTI （SISTI） are pointed out. Because of Hall three dimensions structure＇s enlightenment, a three dimensional logical net diagram in which the system integration of innovation based on problem in real world but not on disciplinary logic is drawn. The intelligent group＇ s need span is greater under the conditions of relatively low material level than common groups who have lower degree of education. The SISTI is composed by multi-rule and intelligent multi-agent behavior. It is concluded that the logical relationships of integrated technology which based on the author＇s experience and observation must be considerded for a valid management of SISTI.展开更多
Joint radar and communication(JRC)technology has become important for civil and military applications for decades.This paper introduces the concepts,characteristics and advantages of JRC technology,presenting the typi...Joint radar and communication(JRC)technology has become important for civil and military applications for decades.This paper introduces the concepts,characteristics and advantages of JRC technology,presenting the typical applications that have benefited from JRC technology currently and in the future.This paper explores the state-of-the-art of JRC in the levels of coexistence,cooperation,co-design and collaboration.Compared to previous surveys,this paper reviews the entire trends that drive the development of radar sensing and wireless communication using JRC.Specifically,we explore an open research issue on radar and communication operating with mutual benefits based on collaboration,which represents the fourth stage of JRC evolution.This paper provides useful perspectives for future researches of JRC technology.展开更多
基金This work was supported in part by the National Science Fund for Distinguished Young Scholars in China under grant 61425012the National Science Foundation Project in China under grant 61931005 and 61731017.
文摘Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.
基金supported by State Grid Corporation of China(No.SGRIDGKJ[2016]123)Education Department of Guangxi Zhuang Autonomous Region(No.2019KY0021)the Natural Science Foundation of Guangxi Province(2019GXNSFBA185004,2018GXNSFAA281308,2019GXNSFAA245050)。
文摘Hydrogen can serve as a carrier to store renewable energy in large scale.However,hydrogen storage still remains a challenge in the current stage.It is difficult to meet the technical requirements applying the conventional storage of compressed gaseous hydrogen in high-pressure tanks or the solid-state storage of hydrogen in suitable materials.In the present work,a gaseous and solid-state(G-S)hybrid hydrogen storage system with a low working pressure below 5 MPa for a 10 kW hydrogen energy storage experiment platform is developed and validated.A Ti-Mn type hydrogen storage alloy with an effective hydrogen capacity of 1.7 wt%was prepared for the G-S hybrid hydrogen storage system.The G-S hybrid hydrogen storage tank has a high volumetric hydrogen storage density of 40.07 kg H_(2)m^(-3) and stores hydrogen under pressure below5 MPa.It can readily release enough hydrogen at a temperature as low as-15C when the FC system is not fully activated and hot water is not available.The energy storage efficiency of this G-S hybrid hydrogen storage system is calculated to be 86.4%-95.9%when it is combined with an FC system.This work provides a method on how to design a G-S hydrogen storage system based on practical demands and demonstrates that the G-S hybrid hydrogen storage is a promising method for stationary hydrogen storage application.
基金Sponsored by the National Natural Science Foundation of China(50371017)Beijing Natural Science Foundation(3062008)
文摘The modern instrument manufacturing has many features, such as high technologies, multiple varieties and small quantities. Aiming at those features, an instrumentation flexible developing system （IFDS） is presented. It constitutes a kind of opening, compatible, extensible and upgradeable flexible developing system, and it will offer a kind of technology equipment for the research and development of new modern instrument products. Its flexible mechanism is able to be suited for different and special requirements of many instrument systems, and its system integrated mechanism is able to adapt to common technological features of most instrument systems. It is IFDS that makes it easy to accomplish a quick system integration of instrument products. IFDS solves key technological problems related to modern instruments development, develops multiple systems for modern instrument development and accomplishes rapid development of series of new products.
文摘Few of the current approaches to achieve the integration of digital library system have considered the influence of network factors on quality of service for the integration system of digital libraries. For this reason, a mobile agent based framework for integrating digital library system is proposed. Based on this framework, a prototype system is implemented and the key technique for it are described. Compared with the current approaches, using mobile agent technique to achieve the integration of digital library system can not only avoid transmitting a lot of data on the network, lower the dependence on network bandwidth for the system, but also improve the quality of service for the integration system of digital libraries in intermitted or unreliable network connection settings.
基金Sponsored bythe National Innovation Basein Management on National Defense Science Technology National Economy Mobilization of the SecondPhase of"985"Project
文摘The causes and the problems of integration of scientific ＆ technical innovation （ISTI） and inevitability are proposed. The status of domestic scientific ＆ technical innovation is analysed. A series of emergent managerial problems caused by the system ISTI （SISTI） are pointed out. Because of Hall three dimensions structure＇s enlightenment, a three dimensional logical net diagram in which the system integration of innovation based on problem in real world but not on disciplinary logic is drawn. The intelligent group＇ s need span is greater under the conditions of relatively low material level than common groups who have lower degree of education. The SISTI is composed by multi-rule and intelligent multi-agent behavior. It is concluded that the logical relationships of integrated technology which based on the author＇s experience and observation must be considerded for a valid management of SISTI.
基金supported by the National Natural Science Foundation of China (No. 61631003, 61601055)the National Science Fund for Distinguished Young Scholars (No. 61525101)
文摘Joint radar and communication(JRC)technology has become important for civil and military applications for decades.This paper introduces the concepts,characteristics and advantages of JRC technology,presenting the typical applications that have benefited from JRC technology currently and in the future.This paper explores the state-of-the-art of JRC in the levels of coexistence,cooperation,co-design and collaboration.Compared to previous surveys,this paper reviews the entire trends that drive the development of radar sensing and wireless communication using JRC.Specifically,we explore an open research issue on radar and communication operating with mutual benefits based on collaboration,which represents the fourth stage of JRC evolution.This paper provides useful perspectives for future researches of JRC technology.
