Environmental impacts of transformative land use and transport developments in the Greater Beijing Region: Insights from a new dynamic spatial equilibrium model

This paper reports the insights into environmental impacts of the ongoing transformative land use and transport developments in Greater Beijing, from a new suite of dynamic land use, spatial equilibrium and strategic transport models that is calibrated for medium to long term land use and transport predictions. The model tests are focused on urban passenger travel demand and associated emissions within the municipality of Beijing, accounting for Beijing’s land use and transport interactions with Tianjin, Hebei and beyond. The findings suggests that background trends of urbanization, economic growth and income rises will continue to be very powerful drivers for urban passenger travel demand across all main modes of transport beyond 2030. In order to achieve the dual policy aims for a moderately affluent and equitable nation and reducing the absolute levels of urban transport emissions by 2030, road charging and careful micro-level coordination between land use, built form and public transport provision may need to be considered together for policy implementation in the near future.     

Evaluation of CO2 emissions from railway resurfacing maintenance activities

This paper is the world first to investigate the CO₂ impact of railway resurfacing in ballasted track bed maintenance. Railway resurfacing is an important routine maintenance activity that restores track geometry to ensure safety, reliability and utility of the asset. This study consisted of an extensive field data collection from resurfacing machineries (diesel-engine tamping machines, ballast regulators and ballast stabilisers) including travel distances, working distances, fuel consumption and construction methodologies. Fuel consumption was converted to a kg CO₂/m using the embodied energies of diesel. Analyses showed that tamping machines emitted the highest CO₂ emissions of the resurfacing machineries, followed by ballast regulators and ballast stabilisers respectively. Tamping machines processed 4.25 m of track per litre of diesel, ballast regulators processed 6.51 m of track per litre of diesel and ballast stabilisers processed 10.61 m of track per litre of diesel. The results were then compared to previous studies and a rigorous parametric study was carried out to consider long-term resurfacing CO₂ emissions on Australian railway track. The outcome of this study is unprecedented and it enables track engineers and construction managers to critically plan strategic rail maintenance and to develop environmental-friendly policies for track geometry and alignment restoration.     

湘桂赣粤运河开发重点问题亟待研究

本文分析推进湘桂赣粤运河连通既是构建高质量国土空间布局的响应,又是促进区域经济协调发展的需要,还是交通强国建设在内河水运的体现,更是契合绿色、低碳发展的生态文明建设,战略意义重大,影响深远,从综合开发角度审视运河工程的必要性、跳出航运探究运河开发的外围技术可行性、基于航运高质量发展突破关键技术难题三个维度提出运河开发亟需研究、有待破解的重点问题。     

南沙国家级新区综合交通发展规划及战略分析

在分析南沙国家级新区交通现状的基础上,介绍其发展目标与战略,详细探讨交通发展规划方案,以促进南沙新区交通水平提升,为南沙社会经济发展提供良好的交通运输基础。     

北京市“十三五”交通节能减排发展目标与策略

“十三五”期间,北京市面临持续增加的客货运输需求,以及日益紧迫的资源环境外在刚性约束,如何取得突破与实质进展成为规划与顶层设计中关注的关键问题。首先,判断北京市交通行业节能减排发展现状及未来形势需求。其次,应用基于单车活动水平的能耗排放模型预测,明确“十三五”末期北京市交通行业节能减排“一控、双降、四提升”的发展目标。围绕目标的实现,从零碳交通系统、客货运输体系、运输装备工具、交通基础设施、交通技术、行为意识,以及交通管理体系几个方面提出交通节能减排发展策略。最后,对城市交通节能减排发展之路提出建议。     

Strategic assessment of capacity consumption in railway networks: Framework and model

In this paper, we develop a new framework for strategic planning purposes to calculate railway infrastructure occupation and capacity consumption in networks, independent of a timetable. Furthermore, a model implementing the framework is presented. In this model different train sequences are generated and assessed to obtain timetable independence. A stochastic simulation of delays is used to obtain the capacity consumption. The model is tested on a case network where four different infrastructure scenarios are considered. Both infrastructure occupation and capacity consumption results are obtained efficiently with little input. The case illustrates the model’s ability to quantify the capacity gain from infrastructure scenario to infrastructure scenario which can be used to increase the number of trains or improve the robustness of the system.     

A dynamic behavioural traffic assignment model with strategic agents

Foresee traffic conditions and demand is a major issue nowadays that is very often approached using simulation tools. The aim of this work is to propose an innovative strategy to tackle such problem, relying on the presentation and analysis of a behavioural dynamic traffic assignment.The proposal relies on the assumption that travellers take routing policies rather than paths, leading us to introduce the possibility for each simulated agent to apply, in real time, a strategy allowing him to possibly re-route his path depending on the perceived local traffic conditions, jam and/or time already spent in his journey.The re-routing process allows the agents to directly react to any change in the road network. For the sake of simplicity, the agents’ strategy is modelled with a simple neural network whose parameters are determined during a preliminary training stage. The inputs of such neural network read the local information about the route network and the output gives the action to undertake: stay on the same path or modify it. As the agents use only local information, the overall network topology does not really matter, thus the strategy is able to cope with large and not previously explored networks.Numerical experiments are performed on various scenarios containing different proportions of trained strategic agents, agents with random strategies and non strategic agents, to test the robustness and adaptability to new environments and varying network conditions. The methodology is also compared against existing approaches and real world data. The outcome of the experiments suggest that this work-in-progress already produces encouraging results in terms of accuracy and computational efficiency. This indicates that the proposed approach has the potential to provide better tools to investigate and forecast drivers’ choice behaviours. Eventually these tools can improve the delivery and efficiency of traffic information to the drivers.     

城市轨道交通绿色低碳发展策略

城轨交通是大容量公共交通的基础设施,是城市引导承载低碳出行的骨干交通方式,当前,我国城轨交通 仍处于快速发展阶段,并继续保持增长态势,其能源消耗和碳减排压力仍将与日俱增。在对我国城轨交通发展机遇、 发展现状、工作基础和面临问题分析的基础上,提出城轨交通绿色低碳发展的目标、重点任务和策略,为城轨交通 加快绿色低碳转型、挖掘节能减排潜力、提高能效水平、推进城轨行业做好“碳达峰、碳中和”工作提供借鉴。     

炮兵作战信息火力一体化目标选择与排序研究

分析了炮兵作战信息火力一体化目标选择与排序的重要性,阐述了炮兵作战信息火力一体化目标排序的选择的过程,提出了目标排序的依据及方法。