摘要
为了准确预测空中交通短期流量,减轻空管协调压力,基于K近邻算法构建了空中交通短期预测模型。首先,通过多次取K值比较相对误差来确定合适的K值。之后,对原有的K近邻模型进行改进,引入空间参数,提出了3种状态向量组合的K近邻模型:时间维度模型、向台航路-时间维度模型与时空参数模型。以某扇区雷达数据对该模型进行检测,结果表明:同时引入时空参数的K近邻模型误差最小,平均为14.16%;基于指数权重的距离衡量方式均能达到预测精度优化的效果;高斯权重预测法在时间维度模型下优于反函数法,引入空间参数则反之;指数权重距离下的反函数法预测的时空参数模型误差为13.94%。改进后的K近邻模型对不同流量情况都具有普适性,预测结果可为空中交通流量管理提供理论参考。
It's worth to predict available short-term air traffic flow and reduce ATCO workload. An air traffic flow model is built based on K-nearest neighbor. First, relative errors from different K values are compared to determine the appropriate K values. After that, space parameter is introduced to improve the model. Then these three kinds of state vectors are combined and new K-nearest neighbor models are proposed including time dimension model, to route-time dimension model and time-space parameter model. Radar data within a certain sector is used to test K-neighbor model, showing out that K-nearest neighbor model with time-space parameter has minimum error,whose average error equals to 14.6%. Distance measuring method based on weight index can attain the goal of prediction accuracy optimization. Gaussian function can produce a better result under time parameter model while it is weaker when space parameter is taken into consideration. Statistics show prediction 's error is only 13.94% under the index weight distance method of inverse function model with time-space parameter. The improved K-nearest neighbor model has applicability for different traffic situations and strong portability for complicated air traffic situation of China.
引文
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