图解法在公路运输企业中的应用

结合公路运输企业实际问题,以实例形式将运筹学中线性规划的图解法运用于制定运输计划之中,尤其对图解法的适用范围、条件及具体操作步骤做了详细介绍。     

A study on the timing of Asian metropolitan railway development with motorization and its effect on CO2 emissions from transportation

In metropolitan areas of developing and emerging economies in Asia, a remarkable phenomenon of motorization with rapid economic growth is accelerating a continuous formation of auto-dependent urban structures. The delayed timing of urban railway introduction could contribute to a negative spiral of motorization, which could provoke a severe increase in CO₂ emissions from transportation sector. In this paper, we attempt to evaluate the timing of urban railway station development based on the level of automobile share and an analysis of the CO₂ emissions in the catchment areas of newly introduced urban railway stations in Asian metropolitan areas; Japan, Malaysia and Indonesia. The result quantitatively reveals that the earlier development of the stations in comparison to the progress of motorization tended to result in a statistically significant reduction of CO₂ emissions from transportation year-by-year in the catchment areas. In addition, this study demonstrates statistically that urban development harmonized with urban railway systems with a higher service frequency should be a key factor on the strategic realization of low-carbon urban forms along public transportation corridors.     

城市群公路可达性与衔接提升研究

为探究城市群路网服务能力，提升城市群可达性水平，提出以中心城市到其他节点的出行时间作为城市群可达性基数，按照等时线测度交通服务的可达性概念，给出了公路交通以及公路衔接其他交通方式下的城市群可达性测算方法。根据测算出的到中心城市出行时间将各区域划分为不同等级的交通圈，并分别以面积、人口、GDP三项指标的小时交通圈覆盖率对公路交通以及公路衔接其他交通方式下城市群可达性水平进行评价。以关中城市群为例，分别测算了公路网络、公路衔接现状高速铁路网络与公路衔接规划中高速铁路网络3种情景下的城市群可达性。经过比对分析发现，公路衔接高速铁路对扩大城市群2 h交通圈具有重要贡献，其中交通圈等级提升明显的县域主要沿铁路线路分布，且呈现距离中心城市西安越远，提升等级越高的趋势。公路衔接高速铁路模式的优势主要体现在中长距离的出行，即1，2 h交通圈上。在引入规划中的高速铁路、城际铁路后，发现城市群可达性进一步提升，2 h交通圈覆盖率进一步扩大，面积覆盖率达到95%，但城市群内仍有少部分区域距离中心城市的出行时间达到2 h以上，即规划的路网仍不能满足《交通强国建设纲要》中“城市群2小时通达”的目标，需要考虑进一步引入更快速的交通方式并配合完善公路网。     

武汉市轨道交通土地利用存在的问题及对策研究

通过分析提出了武汉市轨道交通建设中土地利用存在的问题主要有轨道交通用地与城市土地利用方式矛盾、轨道交通地下空间使用缺乏法律依据、轨道交通站点周边土地开发模式单一等。根据国家政策从不同的角度提出建议:加大轨道交通系列工作与相关规划衔接,出台地下空间土地利用法律以及转变土地融资方式,以期促进武汉市轨道交通土地的合理利用。     

The causal relationship between GDP and domestic air passenger traffic in Brazil

Abstract

This paper examines the causal relationship between economic growth and domestic air passenger transport in Brazil, using Granger's causality test. Total domestic passenger-kilometres are used as a proxy for air transport demand and gross domestic product as a proxy for economic growth. The test spans the period from 1966 to 2006. The results lead to the acceptance of the hypothesis that there is a unidirectional Granger causal relationship from economic growth to domestic air transport demand in Brazil, having a high elasticity in the short term.     

Incorporation of customer satisfaction in public transport contracts – A preliminary analysis

The design of public transport contracts provides an opportunity to define service quality standards to which an operator can be held accountable. While the specification of service quality standards is a common practice, the relationships between the specifications and customer satisfaction are often methodologically unclear. Based on a South African case study, the paper uses data collected from a group of passengers who have personal cars but choose to use public transport, and a control group of passengers who only use their cars, in the same corridor as the user group, to estimate a service quality conjoint model. The model is used to evaluate the effect of different public transport service packages, defined in terms of different combinations of service attributes, on passenger satisfaction. The paper confirms the need to classify service attributes in terms of their relative impact on passenger satisfaction, at the service design stages, where performance in respect of some attributes has a disproportionate impact on satisfaction, especially where public transport is competing directly with private transport. Practical applications and limitations of the methodology are also discussed.     

Non‐physical barriers to traffic flow and the PTA programme of action: problems and prospects

A lot of resources have .been committed to the provision of transport infrastructure in Eastern and Southern Africa. Some of these resources have been borrowed from outside and have to be repaid. Hence the need to maximize their use. However, this is being minimized by non‐infrastructural bottlenecks to traffic flow. These range from macro‐economic constraints with implications for passenger (bus) transport such as the non‐availability or acute shortage of foreign exchange to slow, cumbersome documentation procedures particularly for cross‐border traffic.

The Preferential Trade Area (PTA) for Eastern and Southern Africa is geared to the reduction and eventual elimination of actual and potential non‐physical barriers to traffic flow, for which it has instituted a number of schemes. After introductory remarks on the sub‐regional economy, its transport sector and avenues for sub‐regional cooperation and the implementation of these schemes is assessed and other non‐physical barriers yet to be addressed by the PTA are examined before conclusions are drawn.     

城市轨道交通轨道曲线超高计算及其程序实现

城市轨道交通存在着线路条件复杂、车辆变速较快、运营模式多样等特点,导致轨道曲线超高设计面临着诸多不同的复杂工况。在总结超高计算原则及超高要素限值的基础上,探讨单一速度模式、多种速度模式、缓和曲线进入有效站台等不同工况下超高计算方法并实现计算程序化,结论为:根据不同工况合理选择超高要素限值,单一速度模式宜采用平均速度法,多种速度模式宜采用优化的接近高速法,缓和曲线进入有效站台应以站台端部超高不大于15 mm作为限制条件,采用计算机语言实现超高计算程序化可有效提高设计效率。     

Does competitive tendering improve customer satisfaction with public transport? A case study for the Netherlands

During 10 years experience with competitive tendering of regional and local public transport in the Netherlands, national average trip satisfaction of passengers increased from 6.84 to 7.25 (+0.41). This is a remarkable improvement, but a closer look at the data reveals that also in regions without competitive tendering the improvement in satisfaction was substantial. The difference in the improvement for regions with and without tendering is only +0.06. Tendering led in the majority of concession areas to an improvement of average trip satisfaction, but in some 40% of the cases a deterioration was observed. A change of operator in general has a negative impact on satisfaction. We also find that the effect on satisfaction of early tendering is larger than of later tendering. This may well be the consequence of a shift in emphasis of authorities and operators from quality improvement to efficiency improvements. The model building and analysis is based on the comparison per year-pair of regions tendered versus regions non-tendered (in that specific year-pair). So we compare the effects on satisfaction of tendered regions relative to non-tendered regions.An analysis concerning the weighted satisfaction judgments of 15 underlying service attributes revealed that ‘service frequency, on-time performance, travel speed, and vehicle tidiness’ contribute the most to the effect on satisfaction in the tendered regions. We found that new vehicles impact highly on satisfaction with travel speed and vehicle tidiness. The emphasis in the tenders with increasing service frequency, led to an increase in satisfaction but, may have a deteriorating effect on (the satisfaction with) on-time performance.     

地铁突发事故的防范与处理探讨

地铁作为城市繁荣的标志,推动着经济发展与人才的汇集。然而其空间限制、人员密度大等特点成为突发事故的主要"诱因",突发事故的爆发导致人员及财产的双重损失,对城市的社会和国际地位产生负面影响。所以做好突发事故的防范与处理,降低突发事故发生概率十分重要。文章通过对国内外地铁事故进行分析、总结,得出防范措施与处理方法,为地铁的安全运营提供参考依据。