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91.
Bin Yu William H.K. Lam Mei Lam Tam 《Transportation Research Part C: Emerging Technologies》2011,19(6):1157-1170
Provision of accurate bus arrival information is vital to passengers for reducing their anxieties and waiting times at bus stop. This paper proposes models to predict bus arrival times at the same bus stop but with different routes. In the proposed models, bus running times of multiple routes are used for predicting the bus arrival time of each of these bus routes. Several methods, which include support vector machine (SVM), artificial neural network (ANN), k nearest neighbours algorithm (k-NN) and linear regression (LR), are adopted for the bus arrival time prediction. Observation surveys are conducted to collect bus running and arrival time data for validation of the proposed models. The results show that the proposed models are more accurate than the models based on the bus running times of single route. Moreover, it is found that the SVM model performs the best among the four proposed models for predicting the bus arrival times at bus stop with multiple routes. 相似文献
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文章针对高速公路挖方边坡设计的特点和要求,结合依托工程实例,阐述了基于支持向量机和粒子群算法的智能方法在高速公路挖方边坡优化设计中的具体应用,为高速公路挖方边坡优化设计提供参考。 相似文献
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This study aims to determine an eco-friendly path that results in minimum CO2 emissions while satisfying a specified budget for travel time. First, an aggregated CO2 emission model for light-duty cars is developed in a link-based level using a support vector machine. Second, a heuristic k-shortest path algorithm is proposed to solve the constrained shortest path problem. Finally, the CO2 emission model and the proposed eco-routing model are validated in a real-world network. Specifically, the benefit of the trade-off between CO2 emission reduction and the travel time budget is discussed by carrying out sensitivity analysis on a network-wide scale. A greater spare time budget may enable the eco-routing to search for the most eco-friendly path with higher probability. Compared to the original routes selected by travelers, the eco-friendly routes can save an average of 11% of CO2 emissions for the trip OD pairs with a straight distance between 6 km and 9 km when the travel time budget is set to 10% above the least travel time. The CO2 emission can also be reduced to some degree for other OD pairs by using eco-routing. Furthermore, the impact of market penetration of eco-routing users is quantified on the potential benefit for the environment and travel-time saving. 相似文献
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贾长海 《筑路机械与施工机械化》1995,12(2):22-23
简要叙述了KNAUER400-5大型水泥混凝土预制件制作机液压系统的结构和工作原理,并对液压系统的技术性能特点进行了详细分析. 相似文献
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地下气动穿孔机是一种新型的非开挖施工机械。简述了该设备的工作原理、施工特点,着重分析了设计思想、结构原理和制造过程中应注意的问题,对推动气动穿孔机在非开挖穿孔中的应用具有参考价值。 相似文献