More gray hair—but for whom? Scenario-based simulations of elderly activity travel patterns in 2020

This paper reports the results of a scenario-based simulation study to explore mobility effects of an aging society in the Netherlands. Four accumulative behavioral scenario variants, embedded in an economic and demographic scenario are used to simulate possible future activity-travel patterns, using the Albatross system as the simulator. The variants account for likely differences in activity-travel behavior between elderly today and elderly in the future. Trends ongoing over the last decade in the Netherlands suggest that future elderly need to work longer, change their activity pattern with most growth occurring in the social/leisure activity category, will try to avoid morning peak hours by rescheduling their activities and may introduce more spatial diversity in terms of their residence location. Results show that these behavioral and spatial changes lead to a significant increase in travel demands as well as temporal, spatial and modal shifts in mobility patterns. We discuss possible policy implications of these predictions and evaluate the specific strength of activity-based models for studies of this kind.

基于SEM模型的轨道交通企业员工满意度评价

员工满意度的高低直接影响着企业经营活动的效率。本文首先介绍了结构方程模型（SEM模型）的基本原理,然后从轨道交通企业的特点出发,建立了轨道交通企业员工满意度评价的SEM模型及指标体系,最后以深圳地铁运营分公司员工满意度评价为例,对SEM模型进行了实证性研究。     

航运对长江生态环境的影响和绿色航运体系研究

总结长江航运业对长江水、气、声、生态造成的影响,认为其污染具有长期性、分散性、固定性、流动性和复杂性的特点。为此,构建以生态港口和航道以及新型船舶制造为核心,以行业标准、环境监测网和科学研究为支撑的一套完整的绿色航运体系,对长江航运建设和绿色航运理念的推广具有借鉴意义。     

城市公交项目经济评价中的运营成本估算方法

本文从分析城市公交运营成本的构成出发,探索运用不同的公交运营指标分别计量各类运营成本的途径,并以一个简化的快速公交项目为实例,介绍了项目运营成本的估算方法和步骤,对可行性研究阶段的城市公交项目的经济评价工作具有一定的借鉴意义。     

The value of time and external benefits in bicycle appraisal

We estimate the value of time savings, different cycling environments and additional benefits in cost-benefit analysis of cycling investments. Cyclists’ value of travel time savings turns out to be high, considerably higher than the value of time savings on alternative modes. Cyclists also value other improvements highly, such as separated bicycle lanes. As to additional benefits of cycling improvements in the form of health and reduced car traffic, our results do not support the notion that these will be a significant part in a cost-benefit analysis. Bicyclists seem to take health largely into account when making their travel choices, implying that it would be double-counting to add total health benefits to the analysis once the consumer surplus has been correctly calculated. As to reductions in car traffic, our results indicate that the cross-elasticity between car and cycle is low, and hence benefits from traffic reductions will be small. However, the valuations of improved cycling speeds and comfort are so high that it seems likely that improvements for cyclists are cost-effective compared to many other types of investments, without having to invoke second-order, indirect effects. In other words, our results suggest that bicycle should be viewed as a competitive mode of travel and not primarily as a means to achieve improved health or reduced car traffic.     

长江航运污染事故经济损失评估模型探讨

为更好地为长江流域生态环境问题的解决提供重要的信息基础和决策依据，必须对长江航运产生的污染损失进行价值化描述。运用风险评估和环境经济学相关方法，对“8．5”“长阳”轮重大污染事故产生的经济损失进行了定量评估。     

内外贸同船运输下长江经济带穿梭巴士网络优化

为研究内外贸同船运输政策对航运企业布局长江经济带穿梭巴士网络的影响,本文允许同一船舶同时运输内贸集装箱和外贸集装箱,以总运输成本最小化为目标,考虑服务频率、多航次、时间窗、载重量等约束,构建基于轴辐式的长江经济带集装箱穿梭巴士网络优化模型。针对该模型,本文设计了包含5种破坏算子和2种修复算子的自适应大邻域算法求解模型,并选取上海和长江干线19个港口间的内贸集装箱运输和外贸集装箱运输进行实证分析。研究结果表明：实施内外贸同船政策可节约23.6%的总运输成本,提升平均舱位利用率至87%。该政策改变了原有穿梭巴士的网络结构,直达航次比例增加17%,加快了穿梭巴士的周转。同时,相比于设置1个枢纽港,长江经济带下游将南京港和太仓港共同设置为枢纽港更有利于中上游内外贸集装箱的中转,可节约6%～17%的总运输成本。     

LNG重型牵引车经济性及动力性研究

文章针对不同动力匹配的LNG重型牵引车,采用CRUISE仿真分析与车辆实际运行数据分析相结合的方法进行经济性及动力性研究,确定了仿真分析方法的可行性,为通过仿真分析进行动力匹配的优化提供了借鉴.     

Factors and scenario analysis of transport carbon dioxide emissions in rapidly-developing cities

To identify key factors of transport CO₂ emissions and determine effective policies for emission reductions in fast-growing cities, this study establishes transport CO₂ emission models, quantifying the influences of polycentricity and satellite cities and re-examining the effects of per capita GDP and metro service. Based on the model results, we forecast future residents’ urban transport CO₂ emissions under several scenarios of different urban and transport policies and new energy technologies. We find nonlinear quadratic growth relationship between commuting CO₂ emissions and per capita GDP, and the elasticities of household and individual commuting CO₂ emission to per capita GDP are 1.90% and 1.45%, respectively. Developing job-housing balanced satellite cities and self-contained polycentric city can greatly decrease emissions from high emitters and can contribute to about 51–82% of the emission reductions by 2050 compared with the scenario of business as usual (BAU). Promotion of electric vehicles, electric public buses, metros, and improvement of traditional energy efficiency contributes to about 48–57% of the emission reductions by 2050 compared with the BAU. When these policies and technologies are combined, about 90% of the emissions could be reduced by 2050 compared with the BAU, and the emissions will be about 1.2–4.9 times of the present. The findings suggest that fostering polycentric urban form and job-housing balanced satellite cities is the key step for future transport CO₂ emission reductions. Metro network promotion, energy efficiency improvement, and new energy type applications can also be effective in emission reductions.     

Transporting Singapore—The Air‐Conditioned Nation

Abstract

The role of a metaphor of centrally controlled air conditioning in governing Singaporean transport planning is examined, and its consequences evaluated. A modern transportation system has been put in place to link a hierarchy of central places. Tight government control has made change possible. A reliance on technical expertise at the expense of public involvement has, however, failed to develop public transport to effectively serve a range of dispersed‐destination travel needs. Regulatory approaches, furthermore, have discouraged service innovation. Policies making car purchase expensive have restricted car ownership. Effective change would be facilitated by involving a highly educated public more in decision‐making.