When a train runs at high speeds, the external exciting frequencies approach the natural frequencies of bogie critical components, thereby inducing strong elastic vibrations. The present international reliability test...When a train runs at high speeds, the external exciting frequencies approach the natural frequencies of bogie critical components, thereby inducing strong elastic vibrations. The present international reliability test evaluation standard and design criteria of bogie frames are all based on the quasi-static deformation hypothesis. Structural fatigue damage generated by structural elastic vibrations has not yet been included. In this paper, theoretical research and experimental validation are done on elastic dynamic load spectra on bogie frame of high-speed train. The construction of the load series that correspond to elastic dynamic deformation modes is studied. The simplified form of the load series is obtained. A theory of simplified dynamic load–time histories is then deduced. Measured data from the Beijing–Shanghai Dedicated Passenger Line are introduced to derive the simplified dynamic load–time histories. The simplified dynamic discrete load spectra of bogie frame are established. Based on the damage consistency criterion and a genetic algorithm, damage consistency calibration of the simplified dynamic load spectra is finally performed. The computed result proves that the simplified load series is reasonable. The calibrated damage that corresponds to the elastic dynamic discrete load spectra can cover the actual damage at the operating conditions. The calibrated damage satisfies the safety requirement of damage consistency criterion for bogie frame. This research is helpful for investigating the standardized load spectra of bogie frame of high-speed train.展开更多
A 10Gb/s 6-tap transmit equalizer based on partial response signaling for high speed backplane transmission is presented. By combining features of equalizer and frequency-dependent channel,duobinary signaling can be g...A 10Gb/s 6-tap transmit equalizer based on partial response signaling for high speed backplane transmission is presented. By combining features of equalizer and frequency-dependent channel,duobinary signaling can be generated at the output of FR4 backplane,aiming at increasing data rate while reducing design complexity. Based on 0.18μm CMOS technology,this equalizer has been designed and fabricated,in which both variable capacitor and load resistor calibration techniques are explored to eliminate the effect of process variations. The chip occupies 0.68×0.8mm^2 including I/O pads and consumes a power of 194 mW with 1.8V power supply. Measurement results show that a typical 3-level eye diagram can be obtained at the receiver and the equalizer can work properly at the data rate of 10Gb/s.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.U1134201)
文摘When a train runs at high speeds, the external exciting frequencies approach the natural frequencies of bogie critical components, thereby inducing strong elastic vibrations. The present international reliability test evaluation standard and design criteria of bogie frames are all based on the quasi-static deformation hypothesis. Structural fatigue damage generated by structural elastic vibrations has not yet been included. In this paper, theoretical research and experimental validation are done on elastic dynamic load spectra on bogie frame of high-speed train. The construction of the load series that correspond to elastic dynamic deformation modes is studied. The simplified form of the load series is obtained. A theory of simplified dynamic load–time histories is then deduced. Measured data from the Beijing–Shanghai Dedicated Passenger Line are introduced to derive the simplified dynamic load–time histories. The simplified dynamic discrete load spectra of bogie frame are established. Based on the damage consistency criterion and a genetic algorithm, damage consistency calibration of the simplified dynamic load spectra is finally performed. The computed result proves that the simplified load series is reasonable. The calibrated damage that corresponds to the elastic dynamic discrete load spectra can cover the actual damage at the operating conditions. The calibrated damage satisfies the safety requirement of damage consistency criterion for bogie frame. This research is helpful for investigating the standardized load spectra of bogie frame of high-speed train.
基金Supported by the National Natural Science Foundation of China(No.61471119)
文摘A 10Gb/s 6-tap transmit equalizer based on partial response signaling for high speed backplane transmission is presented. By combining features of equalizer and frequency-dependent channel,duobinary signaling can be generated at the output of FR4 backplane,aiming at increasing data rate while reducing design complexity. Based on 0.18μm CMOS technology,this equalizer has been designed and fabricated,in which both variable capacitor and load resistor calibration techniques are explored to eliminate the effect of process variations. The chip occupies 0.68×0.8mm^2 including I/O pads and consumes a power of 194 mW with 1.8V power supply. Measurement results show that a typical 3-level eye diagram can be obtained at the receiver and the equalizer can work properly at the data rate of 10Gb/s.
