An inevitable trend has already taken shape for the application of the 5th Generation Mobile Communication Technology(5G)in the railway sector.The application scenarios and business types of the railway sector are com...An inevitable trend has already taken shape for the application of the 5th Generation Mobile Communication Technology(5G)in the railway sector.The application scenarios and business types of the railway sector are complex and diverse,so it is indispensable to test and verify the railway 5G before actual deployment.The design and creation of the railway 5G integrated innovation test platform provides engineering design,test and verification conditions for the networking,coverage and business development of 5G public networks and 5G-R in railway scenarios.This paper introduces the design of the overall architecture for the integrated railway 5G innovation test platform according to the railway network requirements,application scenarios and intelligent development trend;respectively elaborates on the design of the 5G-R core network,bearer network and wireless access along loop tracks,in combination with the characteristics of railway scenarios and the requirements of railway dispatching,operation and safety;raises further solutions on the network deployment and coverage schemes of 5G public networks so as to meet the application requirements of 5G public networks.The study results show that the integrated railway 5G innovation test platform scheme contains co-existence of 5G public and private networks,combines the indoor and outdoor scenarios,as well as takes into account of the dynamic and static tests so as to meet the environmental requirements for the integrated railway 5G test and application of all network functions,for which it can provide comprehensive technical support for railway 5G technology research and development,standard formulation,testing,etc.展开更多
The real-time transient stability detection and emergency control technology based on wide area response has become a hot research area in power system stability studies.Several different technologies have been propos...The real-time transient stability detection and emergency control technology based on wide area response has become a hot research area in power system stability studies.Several different technologies have been proposed,but lots of problems remain to be solved before they can be applied in practice.A wide area measurement system(WAMS)based test platform is developed for transient stability detection and control.The design as well as main function modules of the platform are introduced.In addition,three generator power angle prediction methods and six response based transient instability detection technologies are given.Results of engineering application demonstrate that the developed test platform can provide a real-time operation environment,which can effectively compare and analyze the validity and practicability of these transient stability detection technologies.Based on the measured perturbed trajectories from actual power systems or the Real-Time Digital Simulators(RTDS),the platform can realize the assessment and visual result presentation of various responses from different transient instability detection technologies.The test platform can be applied to different power systems and it is convenient to embed new transient instability detection modules.Meanwhile some deficiencies and shortcomings in engineering application are pointed out and corresponding suggestions are given.In conclusion,the hardware and software structure,function modulus and engineering applications are presented.The application in actual power systems shows that it has a good application perspective.展开更多
In order to test the performance of detector prototypes in a laboratory environment, we design and build a large area (90 crux52 cm) test platform for cosmic rays based on a well-designed Multi-gap Resistive Plate C...In order to test the performance of detector prototypes in a laboratory environment, we design and build a large area (90 crux52 cm) test platform for cosmic rays based on a well-designed Multi-gap Resistive Plate Chamber (MRPC) with excellent time resolution and a high detection efficiency for minimum ionizing particles. The time resolution of the MRPC module used is tested to be -80 ps, and the position resolution along the strip is -5 mm, while the position resolution perpendicular to the strip is -12.7 ram. The platform constructed by four MRPC modules can be used for tracking cosmic rays with a spatial resolution of -6.3 mm, and provide a reference time -40 ps.展开更多
As a new type of crop protection machine,the crop protection unmanned aerial system(CPUAS)is developing rapidly in China.The wind field generated by the rotor has a great influence on the deposition and penetration of...As a new type of crop protection machine,the crop protection unmanned aerial system(CPUAS)is developing rapidly in China.The wind field generated by the rotor has a great influence on the deposition and penetration of spraying droplets.The purpose of this study was to develop a reliable and stable test platform that could be used for wind field test of CPUAS,and to carry out the downwash experiments on the platform to obtain the downwash distribution law of a CPUAS Z-3N(100 kg level,Nanjing Research Institute on Simulation Technique,Nanjing,China).The tests showed that the performances of the developed platform could meet the expected design requirements.The platform operated stably and reliably during the downwash experiments of Z-3N,which indicated it could be applied for CPUASs of 100 kg level and below.The vibration characteristics of the platform with different heights(2.0 m,3.0 m,5.0 m,7.0 m,10.0 m)were obtained through modal analysis,which could effectively guide avoiding the resonance for stable and reliable operation during the experiments with the tested CPUAS Z-3N.A ring-radial method was designed combined with the platform for the downwash measurement.The experimental results showed that the downwash distribution of Z-3N was not symmetrical;the downwash wind speed decreased with the increase of the radial distance while the changing trend was not consistent as the height increased.Moreover,the area with high wind speed was mainly within 3.0 m of the radial distance,and the maximum value was 11.37 m/s.The study provided a new way for wind field test of CPUASs and would provide some references for better utilization of wind field during the CPUAS spraying.展开更多
A novel asymmetrical pitch system for rotary wing is presented. The pitch control characteristics are studied and analyzed. Because elastic linkage is a key part in whole asymmetrical pitch system, in order to obtain ...A novel asymmetrical pitch system for rotary wing is presented. The pitch control characteristics are studied and analyzed. Because elastic linkage is a key part in whole asymmetrical pitch system, in order to obtain the variation of the elastic linkage deformation, an experimental platform mainly based on the device of micro aerial vehicles (MAVs) and a new control system mounted on TMS320LF2407 are designed. This control system has its compacted configuration and reliability. Finally, using this system to control the MAV for simulating the flying forward, experimental results show the MAV's flight attitude can he controlled based on the variation of the elastic linkage.展开更多
Beijing Aerospace System Engineering Institute of China Academy of Launch Vehicle Technology (CALT) declared recently that theinstitute has set up a laboratory whichwould operate a newly
To investigate the natural frequencies and towing behaviors of a 3-bucket foundation platform at different drafts, the decay and towing experiments were carried out in a towing tank on a scale of 1:20. The air pressur...To investigate the natural frequencies and towing behaviors of a 3-bucket foundation platform at different drafts, the decay and towing experiments were carried out in a towing tank on a scale of 1:20. The air pressure inside the bucket foundations, the water pressure at the bottom of the bucket foundations, the acceleration of the platform and the towing force were determined in the test process. The time-history curves of the measured parameters were obtained, and the frequency responses of the parameters at different drafts were analyzed by means of fast Fourier transform(FFT). The results showed that the platform natural frequency of heave decreased slightly with the rise of draft. The natural frequencies of roll and pitch are much lower than that of heave, and they increased slightly with the increase of draft. When towing in the following sea, the maximum acceleration of surge, sway and heave has downward trends with the increase of draft, but the change range decreased gradually with the increase of draft. When the draft is 5.0 m(the ratio of draft to bucket height is 0.56), the towing dynamic responses achieve the maximum, which is not conducive to the towing of the platform. When the draft is 6.0 m(the ratio of draft to bucket height is 0.67), the towing dynamic responses are the most stable.展开更多
文摘An inevitable trend has already taken shape for the application of the 5th Generation Mobile Communication Technology(5G)in the railway sector.The application scenarios and business types of the railway sector are complex and diverse,so it is indispensable to test and verify the railway 5G before actual deployment.The design and creation of the railway 5G integrated innovation test platform provides engineering design,test and verification conditions for the networking,coverage and business development of 5G public networks and 5G-R in railway scenarios.This paper introduces the design of the overall architecture for the integrated railway 5G innovation test platform according to the railway network requirements,application scenarios and intelligent development trend;respectively elaborates on the design of the 5G-R core network,bearer network and wireless access along loop tracks,in combination with the characteristics of railway scenarios and the requirements of railway dispatching,operation and safety;raises further solutions on the network deployment and coverage schemes of 5G public networks so as to meet the application requirements of 5G public networks.The study results show that the integrated railway 5G innovation test platform scheme contains co-existence of 5G public and private networks,combines the indoor and outdoor scenarios,as well as takes into account of the dynamic and static tests so as to meet the environmental requirements for the integrated railway 5G test and application of all network functions,for which it can provide comprehensive technical support for railway 5G technology research and development,standard formulation,testing,etc.
基金Supported by National Natural Science Foundation of China(51577049)Open Foundation of State Key Lab.of Alternate Electrical Power System with Renewable Energy Sources(Grant No.LAPS14005).
文摘The real-time transient stability detection and emergency control technology based on wide area response has become a hot research area in power system stability studies.Several different technologies have been proposed,but lots of problems remain to be solved before they can be applied in practice.A wide area measurement system(WAMS)based test platform is developed for transient stability detection and control.The design as well as main function modules of the platform are introduced.In addition,three generator power angle prediction methods and six response based transient instability detection technologies are given.Results of engineering application demonstrate that the developed test platform can provide a real-time operation environment,which can effectively compare and analyze the validity and practicability of these transient stability detection technologies.Based on the measured perturbed trajectories from actual power systems or the Real-Time Digital Simulators(RTDS),the platform can realize the assessment and visual result presentation of various responses from different transient instability detection technologies.The test platform can be applied to different power systems and it is convenient to embed new transient instability detection modules.Meanwhile some deficiencies and shortcomings in engineering application are pointed out and corresponding suggestions are given.In conclusion,the hardware and software structure,function modulus and engineering applications are presented.The application in actual power systems shows that it has a good application perspective.
基金Supported by National Natural Science Foundation of China(11275196)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA03010100)
文摘In order to test the performance of detector prototypes in a laboratory environment, we design and build a large area (90 crux52 cm) test platform for cosmic rays based on a well-designed Multi-gap Resistive Plate Chamber (MRPC) with excellent time resolution and a high detection efficiency for minimum ionizing particles. The time resolution of the MRPC module used is tested to be -80 ps, and the position resolution along the strip is -5 mm, while the position resolution perpendicular to the strip is -12.7 ram. The platform constructed by four MRPC modules can be used for tracking cosmic rays with a spatial resolution of -6.3 mm, and provide a reference time -40 ps.
基金This research was financially supported by the National Key Research and Development Program of China(Grant No.2017YFD0701000)the National Natural Science Foundation of China(Grant No.31701327)+3 种基金the China Agriculture Research System of MOF and MARA(Grant No.CARS-12)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences,Crop Protection Machinery Team(Grant No.CAAS-ASTIP-CPMT)the Jiangsu Science and Technology Development Plan(Grant No.BE2019305)the Science and Technology Development Plan of Suzhou,Jiangsu Province(Grant No.SNG2020042).
文摘As a new type of crop protection machine,the crop protection unmanned aerial system(CPUAS)is developing rapidly in China.The wind field generated by the rotor has a great influence on the deposition and penetration of spraying droplets.The purpose of this study was to develop a reliable and stable test platform that could be used for wind field test of CPUAS,and to carry out the downwash experiments on the platform to obtain the downwash distribution law of a CPUAS Z-3N(100 kg level,Nanjing Research Institute on Simulation Technique,Nanjing,China).The tests showed that the performances of the developed platform could meet the expected design requirements.The platform operated stably and reliably during the downwash experiments of Z-3N,which indicated it could be applied for CPUASs of 100 kg level and below.The vibration characteristics of the platform with different heights(2.0 m,3.0 m,5.0 m,7.0 m,10.0 m)were obtained through modal analysis,which could effectively guide avoiding the resonance for stable and reliable operation during the experiments with the tested CPUAS Z-3N.A ring-radial method was designed combined with the platform for the downwash measurement.The experimental results showed that the downwash distribution of Z-3N was not symmetrical;the downwash wind speed decreased with the increase of the radial distance while the changing trend was not consistent as the height increased.Moreover,the area with high wind speed was mainly within 3.0 m of the radial distance,and the maximum value was 11.37 m/s.The study provided a new way for wind field test of CPUASs and would provide some references for better utilization of wind field during the CPUAS spraying.
基金supported by the National Natural Science Foundation of China (Grant No.60605028)the National High-Technology Research and Development Program of China (Grant No.2007AA04Z225)+2 种基金the Shanghai Rising-Star Program (Grant Nos.07QA14024, 07QH14006)the Shanghai Shuguang Program (Grant No.07SG47)the Shanghai Leading Key Laboratory of Mechanical Automation and Robotics Science Foundation (Grant No.ZZ0805)
文摘A novel asymmetrical pitch system for rotary wing is presented. The pitch control characteristics are studied and analyzed. Because elastic linkage is a key part in whole asymmetrical pitch system, in order to obtain the variation of the elastic linkage deformation, an experimental platform mainly based on the device of micro aerial vehicles (MAVs) and a new control system mounted on TMS320LF2407 are designed. This control system has its compacted configuration and reliability. Finally, using this system to control the MAV for simulating the flying forward, experimental results show the MAV's flight attitude can he controlled based on the variation of the elastic linkage.
文摘Beijing Aerospace System Engineering Institute of China Academy of Launch Vehicle Technology (CALT) declared recently that theinstitute has set up a laboratory whichwould operate a newly
基金Supported by the National Natural Science Foundation of China(No.51309179)Tianjin Municipal Natural Science Foundation(No.14JCQNJC07000)the State Key Laboratory of Hydraulic Engineering Simulation and Safety(Tianjin University)
文摘To investigate the natural frequencies and towing behaviors of a 3-bucket foundation platform at different drafts, the decay and towing experiments were carried out in a towing tank on a scale of 1:20. The air pressure inside the bucket foundations, the water pressure at the bottom of the bucket foundations, the acceleration of the platform and the towing force were determined in the test process. The time-history curves of the measured parameters were obtained, and the frequency responses of the parameters at different drafts were analyzed by means of fast Fourier transform(FFT). The results showed that the platform natural frequency of heave decreased slightly with the rise of draft. The natural frequencies of roll and pitch are much lower than that of heave, and they increased slightly with the increase of draft. When towing in the following sea, the maximum acceleration of surge, sway and heave has downward trends with the increase of draft, but the change range decreased gradually with the increase of draft. When the draft is 5.0 m(the ratio of draft to bucket height is 0.56), the towing dynamic responses achieve the maximum, which is not conducive to the towing of the platform. When the draft is 6.0 m(the ratio of draft to bucket height is 0.67), the towing dynamic responses are the most stable.