This paper deals with dynamic airspace sectorization (DAS) problem by an improved genetic algorithm (iGA). A graph model is first constructed that represents the airspace static structure. Then the DAS problem is ...This paper deals with dynamic airspace sectorization (DAS) problem by an improved genetic algorithm (iGA). A graph model is first constructed that represents the airspace static structure. Then the DAS problem is formulated as a graph-partitioning problem to balance the sector workload under the premise of ensuring safety. In the iGA, multiple populations and hybrid coding are applied to determine the optimal sector number and airspace sectorization. The sector constraints are well satisfied by the improved genetic operators and protect zones. This method is validated by being applied to the airspace of North China in terms of three indexes, which are sector balancing index, coordination workload index and sector average flight time index. The improvement is obvious, as the sector balancing index is reduced by 16.5 %, the coordination workload index is reduced by 11.2 %, and the sector average flight time index is increased by 11.4 % during the peak-hour traffic.展开更多
为了同时实现应用于步进扫描投影光刻机中的长行程直线电机的高推力密度、低推力波动和低铜损耗,提出了基于多种群遗传算法(multiple population genetic algorithm,MPGA)的环形绕组形式无铁心永磁直线同步电机(air-corepermanent magne...为了同时实现应用于步进扫描投影光刻机中的长行程直线电机的高推力密度、低推力波动和低铜损耗,提出了基于多种群遗传算法(multiple population genetic algorithm,MPGA)的环形绕组形式无铁心永磁直线同步电机(air-corepermanent magnet linear synchronous motor,ACPMLSM)多目标优化设计方法。在建立磁场分析模型的基础上,推导了关键参数的解析表达式。以永磁体、环形绕组的尺寸为变量,以推力体积比、电机常数和推力波动为优化目标,提出了基于权重系数的多目标优化函数,应用搜索能力强、收敛速度快的多种群遗传算法优化电机的结构尺寸。结果表明,在不同的权重系数下,MPGA得到的电机优化设计结果与设计目标具有良好的一致性。有限元仿真和实验结果证明了所提方法的有效性和可行性。展开更多
基金funded by the Joint Funds of the National Natural Science Foundation of China (61079001)
文摘This paper deals with dynamic airspace sectorization (DAS) problem by an improved genetic algorithm (iGA). A graph model is first constructed that represents the airspace static structure. Then the DAS problem is formulated as a graph-partitioning problem to balance the sector workload under the premise of ensuring safety. In the iGA, multiple populations and hybrid coding are applied to determine the optimal sector number and airspace sectorization. The sector constraints are well satisfied by the improved genetic operators and protect zones. This method is validated by being applied to the airspace of North China in terms of three indexes, which are sector balancing index, coordination workload index and sector average flight time index. The improvement is obvious, as the sector balancing index is reduced by 16.5 %, the coordination workload index is reduced by 11.2 %, and the sector average flight time index is increased by 11.4 % during the peak-hour traffic.
文摘为了同时实现应用于步进扫描投影光刻机中的长行程直线电机的高推力密度、低推力波动和低铜损耗,提出了基于多种群遗传算法(multiple population genetic algorithm,MPGA)的环形绕组形式无铁心永磁直线同步电机(air-corepermanent magnet linear synchronous motor,ACPMLSM)多目标优化设计方法。在建立磁场分析模型的基础上,推导了关键参数的解析表达式。以永磁体、环形绕组的尺寸为变量,以推力体积比、电机常数和推力波动为优化目标,提出了基于权重系数的多目标优化函数,应用搜索能力强、收敛速度快的多种群遗传算法优化电机的结构尺寸。结果表明,在不同的权重系数下,MPGA得到的电机优化设计结果与设计目标具有良好的一致性。有限元仿真和实验结果证明了所提方法的有效性和可行性。