The influence of locomotive diesel engine transient operating modes on energy usage

This paper analyzes the influence of transient operating modes in the Cat 3512B-HD and MTU 4000 R41 locomotive diesel engines on their energy usage. This analysis represents an integral component of the technological research and development performed at Lietuvos Geležinkeliai AB (JSC Lithuanian Railways) with the objective of increasing the efficiency of freight transportation with the upgraded 2M62M and modern ER20CF/2ER20CF diesel locomotives. The influence of transient modes on the operating variables of the locomotive diesel engines was evaluated under operational load-cycling conditions to aid in the selection of appropriate parameters (e.g., the train weight, the diesel locomotive type, and the technical characteristics of the diesel locomotive to be modeled) for freight transportation on Lithuanian railway lines. It was determined that the engine’s electronic control system compensates for the negative effects of transient operations on the engine’s energy usage. As a result, the increase in fuel consumption is less than 3% during transient operation when compared to steady-state operation. Through this research, methodological foundations have been formulated and adapted for the use of the mathematical modeling of the transient modes of locomotive diesel engines to optimize freight transportation, resulting in an expected decrease of 10–15% in fuel consumption.     

Reducing the energy consumption of heavy goods vehicles through the application of lightweight trailers: Fleet case studies

Reducing the empty weight of articulated heavy goods vehicle trailers is one avenue that needs to be explored in reducing the carbon footprint of the road freight industry as a whole. A statistical analysis of two heavy goods vehicle fleets operating in the United Kingdom has helped to identify double-deck trailers used in grocery haulage and ‘walking-floor’ trailers used in bulk haulage as two examples of trailers that can benefit significantly from lightweighting. Energy consumption of numerous articulated heavy goods vehicles is quantified through an idealised drive cycle analysis reflecting a long haul journey over a highway. This energy analysis allows for a mass energy performance index to be established. The analysis has shown that reducing the empty weight of trailers by 30% can cause reductions of up to 18% and 11% in mass energy performance index for double-deck trailers and ‘walking-floor’ trailers respectively. Using this approach, trailers that will benefit the most from weight reduction can be identified systematically, allowing for lightweighting strategies to be implemented more effectively. Strategies to reduce empty trailer weight and improve vehicle utilisation are also discussed.     

海运温室气体减排市场机制ETS和GHG FUND的比较研究

海运温室气体排放交易机制(ETS)和基金机制(GHG FUND)是用于海运温室气体减排的2个代表性市场机制.为深入了解这2大机制,对其运行机理、减排效果、运行成本,以及新增碳排放成本进行了深度的解剖和定量分析;指出了机制设计中的不确定性以及对发展中国家、不同运输方式间竞争的不公平性.认为现有设计框架下的ETS和GHG FUND机制作为海运业市场减排机制方案并不妥当,海运业应该在寻求技术和营运的措施减排方面做更多的努力.     

浅谈铁路货场向物流中心转型发展

在对铁路货场与铁路物流中心的定义、功能服务和作业流程进行分析的基础上,对二者进行对比。肯定铁路货场向物流中心转型发展的必要性,指出铁路货场向物流中心转型发展的优势与不足,并结合我国铁路货场现状提出对策。     

组合预测模型在铁路货运量预测中的应用

货运量预测是铁路运输规划的基础,单一预测方法很难准确有效地进行运量预测。探讨组合模型在铁路货运量预测中的应用,以全铁路货运量及社会经济发展状况为样本,对未来铁路货运量进行预测。实证预测结果表明：组合预测模型能有效综合各模型的有用信息,从而提高模型预测精度,与单一模型相比,该方法具有较好的实用价值。     

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甩挂运输是一种被国家大力推广的集约、高效、低碳的先进运输组织方式.本文根据港口改善和提升集疏运组织方式和能力的需求,提出了内河港口的甩挂运输模式;针对内河港口甩挂运输组织中货运场站的选址问题制订了选址步骤;建立了选址数学模型,设计了基于遗传算法的模型求解算法;并建立了基于Arena的仿真模型对备选地址进行评价选择;最后以广东省云浮新港为背景进行案例分析,为其设计了甩挂运输组织模式,运用上面的算法和模型进行场站选址,并使用建模仿真的方法将该方案的集装箱甩挂运输模式与传统公路集装箱运输模式进行对比,检验其优越性.     

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通过考虑国民经济的长期趋势、产业结构、生产布局、运输结构、消费水平等影响铁路集装箱运量的不同因素,选用能够容纳多种影响因素的经济计量方法构建铁路集装箱运量中长期预测模型.根据不同影响因素的特点,将其分别设置为内生变量、外生变量和前期内生变量,形成集装箱运量预测的基本方程组结构.通过对模型的估计和检验(包含整理检验和最终检验)可知,所构建的模型体系误差率较小,具有较高的精度,可用于铁路集装箱运量的预测,为铁路集装箱运输发展规划提供基础数据依据.     

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衔接多种运输方式之间中转货流的通用型综合交通枢纽是国家综合货物运输网路体系中的重要节点,同时也是城市交通网络的重要组成部分.本文运用无缝中转的思想,从综合交通枢纽与城市交通网络之间的动态关系出发,既保证用户广义费用最低,同时使整个货物运输系统的社会效益最大,从而构建综合交通枢纽货运站布局优化模型.该模型在考虑四种运输方式基础上,加入城市货流作为第五种运输方式,增强了模型的优越性.通过应用遗传算法求解模拟算例,验证了模型的合理性及遗传算法求解该问题的优越性.研究结果表明,该模型与实际情况吻合,是城市综合交通枢纽货运站布局优化的有效方法之一.     

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在城市交通资源日益紧张、交通拥堵日趋严重的形势下,城市货物配送的发展已上升到维护经济稳定、保障和改善民生的高度,发展夜间配送等成为提高运输效率的重要举措.文章结合北京市中心城区货物夜间运输相关调查,从夜间运输货运量、运输车次数、运输比例及分货类夜间运输等方面分析中心城区夜间运输发展现状,并分析发展夜间运输将带来的经济效益、社会效益和节能减排效益.发展夜间运输具有明显的平衡道路资源占用、缓解交通拥堵、提高运输效率、节约人力资源、降低运输成本、促进节能减排等重要作用.按照国家最新发布的降低流通费用、提高流通效率的工作方案要求,夜间运输结合共同配送等举措是城市货运发展的重要方向.