The study of manual control respiratory rhythm trigger acquisition technology in improving image quality of MRCP / 实用放射学杂志

Objective To study the manual control respiratory rhythm trigger acquisition (MCRRTA)technology in improving image quality and shortening acquisition time of the low-field MRCP scan.Methods 40 patients underwent MRCP scans using both automatic respiratory rhythm trigger acquisition (ARRTA)and MCRRTA,and the acquisition time and image quality were also ana-lyzed.Results The acquisition time of MRCP using ARRTA and MCRRTA were 675.13 ± 35.89 s and 546.38 ± 30.61 s respec-tively,exhibiting significant differences using the paired sample t-test (t=13.85,P=0.000).In ARRTA group,the scores of the image quality were 4 in 11 cases (11/40,27.5%);3 in 18 cases (18/40,45.0%);2 in 10 cases (10/40,25.0%);and 1 in only 1 case (1/40,2.5%),respectively.In MCRRTA group,the scores of the image quality were 4 in 25 cases (25/40,65.5%);3 in 10 cases (10/40,25.0%);2 in 5 cases (5/40,12.5%);and no case with 1 score (0/40,0%),respectively.The differences in image quality between two groups were statistically significant using the wilcoxon rank sum test (Z=-3.036,P=0.002).Conclusion MCRRTA technology in low-field MRCP scans can improve significantly image quality and shorten examination time.

Simulation Study on Performance of Control by Man and Machine in the Stage of Final Approaching for Rendezvous and Docking / 航天医学与医学工程

Objective To study the performance evaluation of integration rendezvous and docking(RVD)control by man and machine in order to provide reference for function allocation between man and machine.Method By a rendezvous and docking experimental system,30 male volunteers aged 20～40 took part in the performance evaluation experiments.The RVD integration control success rates and total thruster ignition time were chosen as evaluation indices.Result The experiment showed that if less than three RVD parameters control tasks were completed by the subjects and the rest of parameters control task completed by automation,the RVD success rate would be larger than 80.47% and the fuel consumption would be optimized.In addition,there were ten subjects who finished the whole 6 RVD parameters control tasks by enough train.Conclusion If the astronauts role should be integrated into the RVD control,it is suitable for them to finish the heading,pitch and roll control in order to assure the man-machine system high performance.When astronauts were needed to finish all parameters control,two points should be taken into consideration,enough fuel and unconstraint operation time.