【摘要】 在现有的交通流量预测研究中，并未充分考虑断面道路内不同车道间的交通流量差异性以及上下游断面交通流量相关性。研究了结合主成分分析法（principal component analysis,PCA）与长短期记忆神经网络（long short-term memory,LSTM）的快速路交通流量预测框架，可以满足智能网联技术实时性和准确性的需求。收集城市快速路的交通流量数据，应用快速傅里叶变换方法（fast fourier transform,FFT）进行数据预处理，以提高原始数据的可预测性能；通过PCA方法对车道间的横向及纵向交通流量进行特征融合，建立车道间交通流量的关联性数据，以降低数据维度；并将关联性数据融入到LSTM模型中，进行车道级交通流量预测并汇总其预测结果，得到断面交通流量的预测值。选取武汉市三环线上的城市快速路卡口检测数据对本文方法进行验证。结果表明：考虑车道间差异和上下游断面关联的模型能够提高断面交通流量的预测精度，相较于仅考虑时间特征的断面交通流量预测结果，平均绝对误差、均方根误差和平均绝对百分比误差分别能降低6.66%,6.23%,17.51%；与单独考虑上下游断面关联性或者车道间差异的断面交通流量预测结果相比均具有更好的预测效果，在平均绝对误差、均方根误差和平均绝对百分比误差上的优化幅度，最低可降低1.53%，最高可降低12.88%；此外，所提的模型相较于支持向量机回归（support vector regression,SVR）和随机森林（random forest,RF）算法具有更高的预测精度；并且在分时段预测中，在晚高峰和平峰时段预测精度表现更佳。更多还原

【Abstract】 In the existing traffic flow prediction studies, the differences of traffic flow between different lanes within a cross-section road and the correlation of traffic flow between upstream and downstream cross-sections are not fully considered. This research develops a framework for expressway traffic flow prediction by integrating principal component analysis(PCA) and long short-term memory(LSTM) neural networks, which satisfies the real-time and accuracy requirements of intelligent connected technologies. The traffic flow data of urban expressways are collected, and the fast Fourier transform(FFT) method is applied for data preprocessing to improve the predictability of the original data. PCA is used to fuse the features of lateral and longitudinal traffic flow between lanes, establishing correlated traffic flow data between lanes to reduce data dimensionality. The correlated data is then integrated into the LSTM model for lane-level traffic flow prediction, and the prediction results aggregated to obtain the cross-section traffic flow estimates. The proposed method is validated using traffic data from expressway checkpoint detectors along the Third Ring Road in Wuhan. The results demonstrate that the model considering inter-lane differences and upstream and downstream cross-section correlations can improve the accuracy of cross-section traffic flow prediction. Compared to prediction results that only consider temporal features, the mean absolute error, root mean square error, and mean absolute percentage error can be reduced by 6.66%, 6.23%, and 17.51%, respectively. When compared with models that account for either upstream-downstream correlations or inter-lane differences alone, the proposed model demonstrates superior performance, with reductions in mean absolute error, root mean square error,and mean absolute percentage error ranging from a minimum of 1.53% to a maximum of 12.88%. Additionally, the proposed model demonstrates higher prediction accuracy than support vector regression(SVR) and random forest(RF) algorithms. In time-segmented predictions, the model performs particularly well during the evening peak and off-peak hours.更多还原