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121.
Energy-efficient operation of rail vehicles 总被引:1,自引:0,他引:1
Rongfang Liu Iakov M. Golovitcher 《Transportation Research Part A: Policy and Practice》2003,37(10):917-932
This paper describes an analytical process that computes the optimal operating successions of a rail vehicle to minimize energy consumption. Rising energy prices and environmental concerns have made energy conservation a high priority for transportation operations. The cost of energy consumption makes up a large portion of the Operation and Maintenance (O&M) costs of transit especially rail transit systems. Energy conservation or reduction in energy cost may be one of the effective ways to reduce transit operating cost, therefore improve the efficiency of transit operations.From a theoretical point of view, the problem of energy efficient train control can be formulated as one of the functions of Optimal Control Theory. However, the classic numerical optimization methods such as discrete method of optimum programming are too slow to be used in an on-board computer even with the much improved computation power, today. The contribution of this particular research is the analytical solution that gives the sequence of optimal controls and equations to find the control change points. As a result, a calculation algorithm and a computer program for energy efficient train control has been developed. This program is also capable of developing energy efficient operating schedules by optimizing distributions of running time for an entire route or any part of rail systems.We see the major application of the proposed algorithms in fully or partially automated Train Control Systems. The modern train control systems, often referred as “positive” train control (PTC), have collected a large amount of information to ensure safety of train operations. The same data can be utilized to compute the optimum controls on-board to minimize energy consumption based on the algorithms proposed in this paper. Most of the input data, such as track plan, track profile, traction and braking characteristics, speed limits and required trip time are located in an on-board database and/or they can be transmitted via radio link to be processed by the proposed algorithm and program. 相似文献
122.
在巴郎山隧址区建立两个长期观测气象站,进行为期一年的长期观测,获取了隧址区气象参数,并计算确定巴郎山隧道洞内自然风大小及方向,取95%保证率,自然风速不大于3m/s.自然风主方向由小金吹向映秀,约占65.5%.节能控制模式有按时段控制和实时控制,按时段控制通风方案全年可平均节能9.5%. 相似文献
123.
This paper elaborates on the definitions of inter and multi-modal transport, as well as their differences in terms of performance. A survey of the barriers, both internal and external, to an efficient intermodal transport is included followed by an analysis of the advantages and disadvantages of combining rail transport with the other transport modes. Transhipment technologies for efficient freight service and some examples of freight rail corridors between sea and inland terminals are presented. The integration between air and rail transport is discussed and the potential synergies between air and high-speed rail services are emphasised. The paper concludes with a discussion on energy use for sustainable rail performance. 相似文献
124.
The diagnosis for urban transport sustainability depends on the context of different regions worldwide. We focus in this paper on West and North Africa which reveal similarities but also structural differences which are explored further. The importance of paratransit in its various forms is strongly observed in sub-Saharan Africa and to a lesser extent in North Africa. The attempts to regulate and organise this sector have been difficult; one interesting experience in Dakar occurred during a programme of fleet renewal. In parallel it is observed that there are positive but insufficient experiences of public transport authorities in some cities (Dakar, Abidjan) and similar projects postponed in other cities because of the institutional problems. One also observes the constant difficulties of designing sustainable schemes for bus companies. An answer to this crisis has been found in North Africa, through investment in new mass transport systems. However, mass transport projects in West Africa are very weak in comparison. The gap between public transport costs and income levels there remains a major obstacle to sustainable mobility exacerbated by the poverty of a significant part of the urban population in West Africa. Two other critical factors are also identified affecting sustainable mobility requirements, namely, the urban sprawl and increasing energy costs. Finally the conclusion recommends the use of research and expertise networks in order to help the design and the implementation of suited solutions. 相似文献
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充分利用LED照明灯具的节能优势,利用计算机和智能控制器实现自适应节能控制,针对不同情况和环境,使用不同的算法构件,在保证行车安全的基础上最大限度地实现隧道照明的节能。 相似文献
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介绍了新能源客车的发展背景,根据动力来源的不同对新能源客车进行了分类,并介绍了国内新能源客车的主要产品,探讨了新能源客车的发展瓶颈并提出相应的对策建议。 相似文献
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