According to the special environment conditions and characteristics of high altitude in Northwest China, the study on key technologies of 750-kV transmission and substation projects has gained fruitful results which a...According to the special environment conditions and characteristics of high altitude in Northwest China, the study on key technologies of 750-kV transmission and substation projects has gained fruitful results which are imperative not only to the construction of 750-kV transmission demonstrative project first in China, but also has laid a solid foundation for future UHV transmission constructions.展开更多
Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forw...Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forward. It considers both jerk and slipping work which are the most commonly used quality evaluating indexes of vehicle starting phase. The adaptive control system and its reference model are discussed profoundly. Taking the adaptability to different starting gears and different road conditions as examples, some proving field test records are shown to illustrate the main clutch adaptive control strategy at starting phase. Proving field test gives acceptable results.展开更多
In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially th...In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially the planning on sending power from west to east, North-South supplementation and nationwide interconnection are introduced. In addition, the technologies to be extended in future grid development are briefed, such as HVDC, FACTS and compact transmission line, etc.展开更多
With most primary energy resources far from load centers, the voltage level of power system in China has imperatively been upgraded to meet the demand of long-distance power transmission. The successful commissioning ...With most primary energy resources far from load centers, the voltage level of power system in China has imperatively been upgraded to meet the demand of long-distance power transmission. The successful commissioning of the 750-kV HVAC line in Northwest Power Grid has opened an era of national grid development and brought about a series of technical problems to be faced. This report introduces briefly the current status and policies of UHV development in China.展开更多
Here we summarize multi-terabit long-haul transmission experiment and distributed Raman amplification (DRA) technologies. As well, we investigate the configuration of dispersion-managed fibers for the DRA-based system...Here we summarize multi-terabit long-haul transmission experiment and distributed Raman amplification (DRA) technologies. As well, we investigate the configuration of dispersion-managed fibers for the DRA-based system from the viewpoint of the fiber non-linear effect and required pumping power.展开更多
The presentation will give an overview over different classes of signal impairments in ultra-long-haul and high-speed optical WDM transmission systems and adequate approaches for suppression, mitigation or compensatio...The presentation will give an overview over different classes of signal impairments in ultra-long-haul and high-speed optical WDM transmission systems and adequate approaches for suppression, mitigation or compensation are discussed.展开更多
Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray m...Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces navigation.In this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight distance.Meanwhile, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.展开更多
文摘According to the special environment conditions and characteristics of high altitude in Northwest China, the study on key technologies of 750-kV transmission and substation projects has gained fruitful results which are imperative not only to the construction of 750-kV transmission demonstrative project first in China, but also has laid a solid foundation for future UHV transmission constructions.
文摘Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forward. It considers both jerk and slipping work which are the most commonly used quality evaluating indexes of vehicle starting phase. The adaptive control system and its reference model are discussed profoundly. Taking the adaptability to different starting gears and different road conditions as examples, some proving field test records are shown to illustrate the main clutch adaptive control strategy at starting phase. Proving field test gives acceptable results.
文摘In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially the planning on sending power from west to east, North-South supplementation and nationwide interconnection are introduced. In addition, the technologies to be extended in future grid development are briefed, such as HVDC, FACTS and compact transmission line, etc.
文摘With most primary energy resources far from load centers, the voltage level of power system in China has imperatively been upgraded to meet the demand of long-distance power transmission. The successful commissioning of the 750-kV HVAC line in Northwest Power Grid has opened an era of national grid development and brought about a series of technical problems to be faced. This report introduces briefly the current status and policies of UHV development in China.
文摘Here we summarize multi-terabit long-haul transmission experiment and distributed Raman amplification (DRA) technologies. As well, we investigate the configuration of dispersion-managed fibers for the DRA-based system from the viewpoint of the fiber non-linear effect and required pumping power.
文摘The presentation will give an overview over different classes of signal impairments in ultra-long-haul and high-speed optical WDM transmission systems and adequate approaches for suppression, mitigation or compensation are discussed.
基金supported by the Young Scientists Fund, China (No. 62103021)。
文摘Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces navigation.In this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight distance.Meanwhile, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.
