We investigate the effectiveness of the hopping parameter expansion（HPE） combined with the Z（2） noise method in the calculation of the trace of the inverse of Wilson＇s Dirac operator and some other disconnected c...We investigate the effectiveness of the hopping parameter expansion（HPE） combined with the Z（2） noise method in the calculation of the trace of the inverse of Wilson＇s Dirac operator and some other disconnected contributions.A numerical comparison of the standard deviation for the Z（2） noise method and HPE with the Z（2） noise method is carried out. It is found that there are noise reductions in all the quantities we calculated using the HPE with the Z（2） noise method. For the trace of the inverse of Wilson＇s Dirac operator, the HPE can reduce the statistical error by about 60%.展开更多
Optoelectronic systems represent the gold standard of technologies used in the motion analysis for the evaluation of kinematics. Trials, a specialty of mountain biking, differ a lot from other cycling specialties, bec...Optoelectronic systems represent the gold standard of technologies used in the motion analysis for the evaluation of kinematics. Trials, a specialty of mountain biking, differ a lot from other cycling specialties, because in addition to pedaling, they require jumping techniques to overcome obstacles that involve the whole body. In this sport, more than in others, the evaluation of technical movements using optoelectronic systems goes far beyond simply assessing the biomechanics of pedaling or the correct positioning on the bike. Starting from a previous study conducted with video analysis technique applied to the lateral jumping technique, two versions of this technique were compared, considering the kinematics of the act, taking into account both the data relating the subject and the bicycle. The joint angles of the lower limbs and the angles described by the bicycle on the three space plane were considered. The major differences have been found in the ＂leap over＂ phase, about the bending of the lower limbs and the angles described by the bicycle.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11335001 and 11275169
文摘We investigate the effectiveness of the hopping parameter expansion（HPE） combined with the Z（2） noise method in the calculation of the trace of the inverse of Wilson＇s Dirac operator and some other disconnected contributions.A numerical comparison of the standard deviation for the Z（2） noise method and HPE with the Z（2） noise method is carried out. It is found that there are noise reductions in all the quantities we calculated using the HPE with the Z（2） noise method. For the trace of the inverse of Wilson＇s Dirac operator, the HPE can reduce the statistical error by about 60%.
文摘Optoelectronic systems represent the gold standard of technologies used in the motion analysis for the evaluation of kinematics. Trials, a specialty of mountain biking, differ a lot from other cycling specialties, because in addition to pedaling, they require jumping techniques to overcome obstacles that involve the whole body. In this sport, more than in others, the evaluation of technical movements using optoelectronic systems goes far beyond simply assessing the biomechanics of pedaling or the correct positioning on the bike. Starting from a previous study conducted with video analysis technique applied to the lateral jumping technique, two versions of this technique were compared, considering the kinematics of the act, taking into account both the data relating the subject and the bicycle. The joint angles of the lower limbs and the angles described by the bicycle on the three space plane were considered. The major differences have been found in the ＂leap over＂ phase, about the bending of the lower limbs and the angles described by the bicycle.
