交通流预测是交通智慧化的重要任务。为了提高短时交通流的预测精度,解决单一模型预测精度不足、易受噪声干扰等特点,提出了一种基于随机拓扑优化的提升回声状态网络(echo state networks, ESN)的预测方法。该方法以简单的回声状态网络...交通流预测是交通智慧化的重要任务。为了提高短时交通流的预测精度,解决单一模型预测精度不足、易受噪声干扰等特点,提出了一种基于随机拓扑优化的提升回声状态网络(echo state networks, ESN)的预测方法。该方法以简单的回声状态网络为基本构成单元,利用随机拓扑优化策略对回声状态网络的拓扑结构进行优化选择,然后利用基于误差补偿的提升算法提高整体模型的预测精度。通过对随机拓扑优化策略和提升算法在实际交通流预测问题中的性能分析,验证了所提方法的可行性和有效性,同时可为其他弱预测学习器的学习性能改进提供参考。展开更多
The device that consists of tank and disk agitator for evaluation drag reduction agents(DRA) was established.The effect of DRA was defined by testing the changes of agitator torque that drives the disk rotation.The HG...The device that consists of tank and disk agitator for evaluation drag reduction agents(DRA) was established.The effect of DRA was defined by testing the changes of agitator torque that drives the disk rotation.The HG-DRA for oil pipeline from Linyi to Puyang was studied by agitator tank device.The relationships between the drag reduction rate and Reynolds number,concentration,balance time were studied.The best concentration and the highest Renords number for the best drag reduction rate were confirmed.The results show that the drag reduction rate tested in agitator tank is close to that in pipeline.The maximum error of drag reduction rate between pipeline and agitator tank is 18.3%,which indicates that the agitator tank device is available to evaluate the effect of DRA for pipeline and it also has the advantages of simple,easy to be operated and using small volume of oil.Those are very helpful for operaters to know the properties of DRA and operate pipeline well.展开更多
文摘交通流预测是交通智慧化的重要任务。为了提高短时交通流的预测精度,解决单一模型预测精度不足、易受噪声干扰等特点,提出了一种基于随机拓扑优化的提升回声状态网络(echo state networks, ESN)的预测方法。该方法以简单的回声状态网络为基本构成单元,利用随机拓扑优化策略对回声状态网络的拓扑结构进行优化选择,然后利用基于误差补偿的提升算法提高整体模型的预测精度。通过对随机拓扑优化策略和提升算法在实际交通流预测问题中的性能分析,验证了所提方法的可行性和有效性,同时可为其他弱预测学习器的学习性能改进提供参考。
文摘The device that consists of tank and disk agitator for evaluation drag reduction agents(DRA) was established.The effect of DRA was defined by testing the changes of agitator torque that drives the disk rotation.The HG-DRA for oil pipeline from Linyi to Puyang was studied by agitator tank device.The relationships between the drag reduction rate and Reynolds number,concentration,balance time were studied.The best concentration and the highest Renords number for the best drag reduction rate were confirmed.The results show that the drag reduction rate tested in agitator tank is close to that in pipeline.The maximum error of drag reduction rate between pipeline and agitator tank is 18.3%,which indicates that the agitator tank device is available to evaluate the effect of DRA for pipeline and it also has the advantages of simple,easy to be operated and using small volume of oil.Those are very helpful for operaters to know the properties of DRA and operate pipeline well.
