准移动闭塞系统针对市域快线的适用性分析

针对国内城市轨道交通中被广泛采用的准移动闭塞系统,对市域快线的运营速度、站间距、牵引供电方式等进行分析,从理论上说明基于数字轨道电路的准移动闭塞信号系统可以满足市域快线的要求。     

Pedestrian traffic management of boarding and alighting in metro stations

The objective of this work is to determine, by means of simulation and experiments, the effect of pedestrian traffic management in the boarding and alighting time of passengers at metro stations. Studies were made by means of a pedestrian traffic microsimulator (LEGION Studio) and experiments at the Human Dynamic Laboratory (HDL) of Universidad de los Andes in Santiago de Chile, to obtain criteria for the pedestrian traffic management on the platform and doors of metro cars. The methodology consists of building a boarding/alighting hall of a metro car and the relevant portion of the platform in front of the hall. The simulation scenarios included the location of the vertical handrail in the hall of the car, delimitation of a keep out zone in front of the doors and the use of differentiated doors for boarding and alighting. The results of the simulation and laboratory experiments are expressed in Pedestrian Level of Service (LOS), Passenger Service Time (PST), passenger density on the vehicle and platform, and passenger dissatisfaction. Both, the simulation results and laboratory experiments allow us to give some recommendations for the pedestrian traffic management in metro systems.     

Electric vehicle tour planning

This study extends the orienteering problem with time windows by considering electric vehicles (EV) with limited range. The model can simulate the change in the battery’s state of charge at each point along the routes, and thus can be used to solve the problem of EV tourist trip design with time windows. A land-sea integrated network for Penghu low-carbon islands was tested, and then the optimal green trip designs are obtained using a heuristic method. Some unique properties of the model are also discussed, as well as a number of management or planning implications.     

Using the sustainable modified TAM and TPB to analyze the effects of perceived green value on loyalty to a public bike system

This article explores the effects of perceived green value, perceived green usefulness, perceived pleasure to use, subjective norms and perceived behavioral control on green loyalty to a public bike system. The mediators between perceived green value and green loyalty and a moderator of general attitude toward protecting the natural environment are also discussed. The aim of this research was to understand how to establish green loyalty via the other dimensions based on the sustainable modified technology acceptance model (modified TAM), the theory of planned behavior (TPB), and a moderator. The findings reveal that perceived pleasure to use and subjective norms have the strongest power to influence loyalty for both users and non-users. The implications of this finding are that fun in people’s lives has a strong influence on sustainable continuous use of public bikes, and that subjective norms are more effective for non-users. In addition, environmental attitude has stronger moderating effects for non-users than for users on perceived green usefulness, perceived pleasure and subjective norms. Therefore, governmental policies should promote the attitude of protecting the natural environment, perceptions of pleasure, and subjective norms so as to increase green loyalty to public bike-sharing.     

Siting public electric vehicle charging stations in Beijing using big-data informed travel patterns of the taxi fleet

Charging infrastructure is critical to the development of electric vehicle (EV) system. While many countries have implemented great policy efforts to promote EVs, how to build charging infrastructure to maximize overall travel electrification given how people travel has not been well studied. Mismatch of demand and infrastructure can lead to under-utilized charging stations, wasting public resources. Estimating charging demand has been challenging due to lack of realistic vehicle travel data. Public charging is different from refueling from two aspects: required time and home-charging possibility. As a result, traditional approaches for refueling demand estimation (e.g. traffic flow and vehicle ownership density) do not necessarily represent public charging demand. This research uses large-scale trajectory data of 11,880 taxis in Beijing as a case study to evaluate how travel patterns mined from big-data can inform public charging infrastructure development. Although this study assumes charging stations to be dedicated to a fleet of PHEV taxis which may not fully represent the real-world situation, the methodological framework can be used to analyze private vehicle trajectory data as well to improve our understanding of charging demand for electrified private fleet. Our results show that (1) collective vehicle parking “hotspots” are good indicators for charging demand; (2) charging stations sited using travel patterns can improve electrification rate and reduce gasoline consumption; (3) with current grid mix, emissions of CO₂, PM, SO₂, and NO_x will increase with taxi electrification; and (4) power demand for public taxi charging has peak load around noon, overlapping with Beijing’s summer peak power.     

基于"微中心"理念的轨道交通既有线站点改造提升研究

随着城市的发展和客流特征的变化,车站运营出现了新的问题,采用常规的扩能改造无法满足新的需求。借鉴日本东京对既有线改造的经验,北京提出"微中心"的理念,根据站点所在的区位定位、规划条件、客流特征、既有环境等特征进行分类;以13号线五道口站为例,根据所属"微中心"类型,以车站改造提升和城市更新为核心,采用相应的更新设计思路和策略,对车站和周边城市进行整体规划设计,实现轨道交通站点与城市空间的有机融合,实施便捷的交通接驳一体化,优化区域交通组织,整合城市景观,提升车站的服务水平,为其他轨道交通既有站点的提升改造提供参考。     

货运调车场减速顶噪声的特征探讨

通过对昆明东站铁路降噪工程的观测和试验，探讨了减速顶噪声的特性．减速顶噪声主要来源于轮对的垂向激励/垂向响应、垂向激励/横向响应．减速顶的噪声是一种持续时间、多个脉心中、离散频率的噪声．     

站间微机化自动闭塞系统双机冗余系统设计

根据站间自动闭塞系统的高可靠性要求，设计了闭塞机热备冗余方案；针对可能出现的双主机状态，研究了安全控制锁的原理与机制．为了解系统的转换性能，用Petri网对系统进行了建模与分析．分析结果表明，设计的结构与切换机制合理，系统中各状态转换安全、完整，不存在死锁状态．     

地下过滤田污水处理生产试验技术经济分析

地下过滤田是土地处理污水的一种形式。它通过铺设在地下的穿孔布水管将污水均匀而又有组织地散布到人工滤料层中,最终缓慢地渗透、扩散到周围土壤中,在经过土壤的过滤、吸附和生化作用后得到净化。为了验证地下过滤系统对生活污水的处理效果,明确地下过滤田的各项经济技术指标     

Centralized versus distributed feeder ship service: The case of the Maasvlakte harbour area of Rotterdam

Coastal and inland feeder shipping is a critical factor for intercontinental container transport. The question is whether each intercontinental terminal should be equipped with its own service stations for feeder shipping, or whether pooling of the facilities would be more effective. For this paper, the service station examined for the service of feeder ships is equipped with two quay cranes operating in parallel supported by a small active quay stack. The centre for this feeder service consists of several of these stations. Simulation shows that a crane productivity of 96% is feasible with an average vehicle waiting time of 1 min, that a central service requires fewer service stations than a distributed service and that the quay transport for central and distributed transport requires the same number of terminal vehicles. The analysis shows that a centralized service is preferable, attracting 70% of the market potential.