Under the demand of strategic air traffic flow management and the concept of trajectory based operations（TBO）,the network-wide 4D flight trajectories planning（N4DFTP） problem has been investigated with the purpose...Under the demand of strategic air traffic flow management and the concept of trajectory based operations（TBO）,the network-wide 4D flight trajectories planning（N4DFTP） problem has been investigated with the purpose of safely and efficiently allocating 4D trajectories（4DTs）（3D position and time） for all the flights in the whole airway network.Considering that the introduction of large-scale 4DTs inevitably increases the problem complexity,an efficient model for strategiclevel conflict management is developed in this paper.Specifically,a bi-objective N4 DFTP problem that aims to minimize both potential conflicts and the trajectory cost is formulated.In consideration of the large-scale,high-complexity,and multi-objective characteristics of the N4DFTP problem,a multi-objective multi-memetic algorithm（MOMMA） that incorporates an evolutionary global search framework together with three problem-specific local search operators is implemented.It is capable of rapidly and effectively allocating 4DTs via rerouting,target time controlling,and flight level changing.Additionally,to balance the ability of exploitation and exploration of the algorithm,a special hybridization scheme is adopted for the integration of local and global search.Empirical studies using real air traffic data in China with different network complexities show that the proposed MOMMA is effective to solve the N4 DFTP problem.The solutions achieved are competitive for elaborate decision support under a TBO environment.展开更多
多维属性离散化能提升机器学习算法训练的速度与精度,目前的离散化算法性能较低且多是单属性离散,忽略了属性之间的潜在关联。基于此,提出了一种基于森林优化的粗糙集离散化算法(a discretization algorithm based on forest optimizati...多维属性离散化能提升机器学习算法训练的速度与精度,目前的离散化算法性能较低且多是单属性离散,忽略了属性之间的潜在关联。基于此,提出了一种基于森林优化的粗糙集离散化算法(a discretization algorithm based on forest optimization and rough set,FORDA)。该算法针对多维连续属性的离散化,依据变精度粗糙集理论,设计适宜值函数,进而构建森林寻优网络,迭代搜索最优断点子集。在UCI数据集上的实验结果表明,与当前主流的离散化算法相比,所提算法能避免局部最优,显著提升了SVM分类器的分类精度,其离散化性能更为优良,且具有一定的通用性,验证了算法的有效性。展开更多
基金co-supported by the National Science Foundation for Young Scientists of China(No.61401011)the National Key Technologies R&D Program of China(No.2015BAG15B01)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.61521091)
文摘Under the demand of strategic air traffic flow management and the concept of trajectory based operations（TBO）,the network-wide 4D flight trajectories planning（N4DFTP） problem has been investigated with the purpose of safely and efficiently allocating 4D trajectories（4DTs）（3D position and time） for all the flights in the whole airway network.Considering that the introduction of large-scale 4DTs inevitably increases the problem complexity,an efficient model for strategiclevel conflict management is developed in this paper.Specifically,a bi-objective N4 DFTP problem that aims to minimize both potential conflicts and the trajectory cost is formulated.In consideration of the large-scale,high-complexity,and multi-objective characteristics of the N4DFTP problem,a multi-objective multi-memetic algorithm（MOMMA） that incorporates an evolutionary global search framework together with three problem-specific local search operators is implemented.It is capable of rapidly and effectively allocating 4DTs via rerouting,target time controlling,and flight level changing.Additionally,to balance the ability of exploitation and exploration of the algorithm,a special hybridization scheme is adopted for the integration of local and global search.Empirical studies using real air traffic data in China with different network complexities show that the proposed MOMMA is effective to solve the N4 DFTP problem.The solutions achieved are competitive for elaborate decision support under a TBO environment.
文摘多维属性离散化能提升机器学习算法训练的速度与精度,目前的离散化算法性能较低且多是单属性离散,忽略了属性之间的潜在关联。基于此,提出了一种基于森林优化的粗糙集离散化算法(a discretization algorithm based on forest optimization and rough set,FORDA)。该算法针对多维连续属性的离散化,依据变精度粗糙集理论,设计适宜值函数,进而构建森林寻优网络,迭代搜索最优断点子集。在UCI数据集上的实验结果表明,与当前主流的离散化算法相比,所提算法能避免局部最优,显著提升了SVM分类器的分类精度,其离散化性能更为优良,且具有一定的通用性,验证了算法的有效性。
