针对空间光通信中跟踪系统的高精度、宽带宽要求,提出了一种基于PID神经元网络(Proportional integral differential neural network-PIDNN)的控制方案。采用MATLAB对所建立的跟踪系统模型进行了仿真分析研究,对采用PIDNN控制器的精跟...针对空间光通信中跟踪系统的高精度、宽带宽要求,提出了一种基于PID神经元网络(Proportional integral differential neural network-PIDNN)的控制方案。采用MATLAB对所建立的跟踪系统模型进行了仿真分析研究,对采用PIDNN控制器的精跟踪系统的在线训练能力及学习、调整功能进行了仿真验证,同时加入扰动源对精跟踪系统的稳态、动态性能及鲁棒性进行了仿真测试。仿真和测试结果表明:通过PIDNN控制的精跟踪系统具有良好的稳态及动态性能和很强的鲁棒性,系统跟踪精度高且系统带宽较宽。展开更多
This study investigated changes in the complexity (magnitude and structure of variability) of the collective behaviours of association football teams during competitive performance. Raw positional data from an entir...This study investigated changes in the complexity (magnitude and structure of variability) of the collective behaviours of association football teams during competitive performance. Raw positional data from an entire competitive match between two professional teams were obtained with the ProZone tracking system. Five compound positional variables were used to investigate the collective patterns of performance of each team including: surface and geometrical centre. Analyses involve the coefficient (ApEn), as well as the linear association between both area, stretch index, team length, team width, of variation (%CV) and approximate entropy parameters. Collective measures successfully captured the idiosyncratic behaviours of each team and their variations across the six time periods of the match. Key events such as goals scored and game breaks (such as half time and full time) seemed to influence the collective patterns of performance. While ApEn values significantly decreased during each half, the %CV increased. Teams seem to become more regular and predictable, but with increased magnitudes of variation in their organisational shape over the natural course of a match.展开更多
文摘针对空间光通信中跟踪系统的高精度、宽带宽要求,提出了一种基于PID神经元网络(Proportional integral differential neural network-PIDNN)的控制方案。采用MATLAB对所建立的跟踪系统模型进行了仿真分析研究,对采用PIDNN控制器的精跟踪系统的在线训练能力及学习、调整功能进行了仿真验证,同时加入扰动源对精跟踪系统的稳态、动态性能及鲁棒性进行了仿真测试。仿真和测试结果表明:通过PIDNN控制的精跟踪系统具有良好的稳态及动态性能和很强的鲁棒性,系统跟踪精度高且系统带宽较宽。
基金supported by a grant of the Portuguese Foundation for Science and Technology(SFRH/BD/43994/2008)
文摘This study investigated changes in the complexity (magnitude and structure of variability) of the collective behaviours of association football teams during competitive performance. Raw positional data from an entire competitive match between two professional teams were obtained with the ProZone tracking system. Five compound positional variables were used to investigate the collective patterns of performance of each team including: surface and geometrical centre. Analyses involve the coefficient (ApEn), as well as the linear association between both area, stretch index, team length, team width, of variation (%CV) and approximate entropy parameters. Collective measures successfully captured the idiosyncratic behaviours of each team and their variations across the six time periods of the match. Key events such as goals scored and game breaks (such as half time and full time) seemed to influence the collective patterns of performance. While ApEn values significantly decreased during each half, the %CV increased. Teams seem to become more regular and predictable, but with increased magnitudes of variation in their organisational shape over the natural course of a match.