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21.
“八纵八横”高速铁路网货运节点可以利用聚类分析法,依据货运总量、GDP、人口、社会消费品零售总额、快递业务量、线路连接数、城市类别和节点类别等指标划分为4个等级。基于灰色系统预测模型,预测2025年高速铁路货运量,构建数学模型计算保本货运量。依据节点划分、货运量预测、保本货运量结果,计算各等级节点中盈利OD所占的比例,结合日均OD量,分析各等级节点间开办高速铁路货运的可行性。研究表明,在一级节点之间可以开行高速铁路货运动车组专列,在二级节点之间可以开行客货联挂动车组,三、四级节点可以采用捎带运输的方式。  相似文献   
22.
为弥补应急情况下滚装运输所需平车数量缺口,同时为完善车辆自身应急保障能力,分析集装箱专用平车用于滚装运输需求,针对集装箱专用平车用于滚装运输存在的主要问题,提出在不改变车体结构前提下,通过加装承载板实现滚装运输的解决思路。结合集装箱专用平车结构特点,分析承载板的数量、尺寸、材质,设计承载板由承载面、横支撑架、渡板、斜支腿、受力面、绳拴构成,给出加装改造方法,并通过校核承载能力和研究适运范围,研究加装改造后的集装箱专用平车滚装运输能力,得出改造后的集装箱专用平车可以满足大部分滚装运输货物运输需要。  相似文献   
23.
This paper proposes different policy scenarios to cut CO2 emissions caused by the urban mobility of passengers. More precisely, we compare the effects of the ‘direct tool’ of carbon tax, to a combination of ‘indirect tools’ – not originally aimed at reducing CO2 (i.e. congestion charging, parking charges and a reduction in public transport travel time) in terms of CO2 impacts through a change in the modal split. In our model, modal choices depend on individual characteristics, trip features (including the effects of policy tools), and land use at origin and destination zones. Personal “CO2 emissions budgets” resulting from the trips observed in the metropolitan area of Lille (France) in 2006 are calculated and compared to the situation related to the different policy scenarios. We find that an increase of 50% in parking charges combined with a cordon toll of €1.20 and a 10% travel time decrease in public transport services (made after recycling toll-revenues) is the winning scenario. The combined effects of all the policy scenarios are superior to their separate effects.  相似文献   
24.
Congestion charging is being considered as a potential measure to address the issue of substantially increased traffic congestion and vehicle emissions in Beijing. This study assessed the impact of congestion charging on traffic and emissions in Beijing using macroscopic traffic simulation and vehicle emissions calculation. Multiple testing scenarios were developed with assumptions in different charging zone sizes, public transit service levels and charging methods. Our analysis results showed that congestion charging in Beijing may increase public transit use by approximately 13%, potentially reduce CO and HC emissions by 60–70%, and reduce NOx emissions by 35–45% within the charging zone. However, congestion charging may also result in increased travel activities and emissions outside of the charging zone and a slight increase in emissions for the entire urban area. The size of charging zone, charging method, and charging rate are key factors that directly influence the impact of congestion charging; improved public transit service needs to be considered as a complementary approach with congestion charging. This study is used by Beijing Transportation Environment and Energy Center (BTEC) as reference to support the development of Beijing’s congestion charging policy and regulation.  相似文献   
25.
Carpooling is an effective solution to major environmental problems but it is insufficiently used, particularly in France. In order to increase carpooling, it is important to understand why people do or not carpool. This study, carried out a large sample of drivers, was aimed at (1) identifying whether or not people carpool, (2) investigating the factual data (e.g. socio-demographics, transportation accessibility) and motivational factors (e.g. attitudes regarding car use, public transportation, environment) upon which carpoolers and non-carpoolers differ, and (3) highlighting the main determinants of the practice of carpooling. An online survey was administered to 1207 French drivers (48% men, ages 19–87) recruited by means of a random-quota method. In our sample, 52.5% of the participants said they were using carpooling. Carpoolers and non-carpoolers were similar in terms of kilometers driven per year, distance to their workplace or schools/universities, and public transportation accessibility. Compared to non-carpoolers, carpoolers were more likely to be women, have children, have positive attitudes toward public transport, and be more environmentally aware. These results suggest various different strategies for increasing the number of carpoolers and the frequency of carpooling use by taking into account the gender of road users.  相似文献   
26.
Intercity passenger trips constitute a significant source of energy consumption, greenhouse gas emissions, and criteria pollutant emissions. The most commonly used city-to-city modes in the United States include aircraft, intercity bus, and automobile. This study applies state-of-the-practice models to assess life-cycle fuel consumption and pollutant emissions for intercity trips via aircraft, intercity bus, and automobile. The analyses compare the fuel and emissions impacts of different travel mode scenarios for intercity trips ranging from 200 to 1600 km. Because these modes operate differently with respect to engine technology, fuel type, and vehicle capacity, the modeling techniques and modeling boundaries vary significantly across modes. For aviation systems, much of the energy and emissions are associated with auxiliary equipment activities, infrastructure power supply, and terminal activities, in addition to the vehicle operations between origin/destination. Furthermore, one should not ignore the embodied energy and initial emissions from the manufacturing of the vehicles, and the construction of airports, bus stations, highways and parking lots. Passenger loading factors and travel distances also significantly influence fuel and emissions results on a per-traveler basis. The results show intercity bus is generally the most fuel-efficient mode and produced the lowest per-passenger-trip emissions for the entire range of trip distances examined. Aviation is not a fuel-efficient mode for short trips (<500 km), primarily due to the large energy impacts associated with takeoff and landing, and to some extent from the emissions of ground support equipment associated with any trip distance. However, aviation is more energy efficient and produces less emissions per-passenger-trip than low-occupancy automobiles for trip distances longer than 700–800 km. This study will help inform policy makers and transportation system operators about how differently each intercity system perform across all activities, and provides a basis for future policies designed to encourage mode shifts by range of service. The estimation procedures used in this study can serve as a reference for future analyses of transportation scenarios.  相似文献   
27.
With the rapid expansion of the high-speed railway infrastructure in China, conflicts arise between the interests of local citizens living along the planned tracks and the national interests of governmental authorities and project developers. This paper addresses questions of why and how Chinese citizens mobilize for and participate in protests against high-speed railway projects and to what effect. To this end, a comprehensive study was conducted on the decision-making process, public opinions, and protest actions regarding the plans and site choices for the Beijing–Shenyang high-speed railway from 2008 to 2013, combining quantitative and qualitative methods. In general, local residents are supportive of high-speed railway project construction, but they contest the closed decision-making process and the poor design and siting choices for the track by governmental authorities and companies. After four years of resident protests through formal complaints, lobbying, protest demonstrations, organizing alternative opinion polls, and discussions with authorities, citizens were partially successful in changing the siting of the track, adding protective measures (e.g., tunnels and sound screens), and saving green belts. Two conclusions can be drawn from this case study. First, regardless of the growing legal requirements, public participation in major projects in China is far from a standard practice. Final citizen participation is often preceded by serious conflict. Second, with defined good governance boundaries, there is increasing room for public participation in environmental movements, which does influence final decisions.  相似文献   
28.
Walking is an imperative travel mode, especially for short trips. Walking accessibility, which is defined as the ease of reaching essential destinations in the walk-in catchment area, may affect property prices because residents are more likely to be willing to pay for this attribute. In addition, different categories of public services may have varied influencing directions and magnitude. These two hypotheses are tested in this study. Taking Xiamen, China as a case study, we estimate the cumulative opportunities of public services on foot and develop a set of hedonic pricing models (more specifically, two pre-specified ordinary least squares models, four Box-Cox transformed models, and two spatial econometric models) to estimate, whether and to what extent, walking accessibility contributes to price premiums (or discounts). Using a database of 22,586 second-hand residential properties in 358 multi- or high-storey residential complexes, we find that (1) walking accessibility to public services contributes to the variations in housing prices and plays a role in determining housing prices; (2) different categories of services have vastly divergent, even opposite, influencing impacts; and (3) walking accessibility to primary schools, commercial centers, and sports and cultural centers have positive effects on house prices whereas walking accessibility to comprehensive hospitals adversely affects housing prices. Methodologically, we confirm that spatial econometric methods improve estimation accuracy and have more explanatory power relative to the standard non-spatial models. Robustness check analysis further guarantees the plausibility of this study.  相似文献   
29.
优化调整货物运输结构、提高铁路发运占比是落实"蓝天保卫战"的一项具体举措。为了满足宝钢集团新疆八一钢铁有限公司生产规模的不断扩大、外运需求旺盛的实际,在对其铁路运输现状和需求,以及存在的线路质量较差、装卸效率较低、运输组织衔接弱等问题进行剖析的基础上,提出提高铁路货运量对策,即:推进路企直通战略合作、升级改造设备设施、构建调度全程统一指挥模式、优化货流源头组织,以加快调整运输结构,增加铁路货运量,推动铁路高质量发展。  相似文献   
30.
Smart card data are increasingly used for transit network planning, passengers’ behaviour analysis and network demand forecasting. Public transport origin–destination (O–D) estimation is a significant product of processing smart card data. In recent years, various O–D estimation methods using the trip-chaining approach have attracted much attention from both researchers and practitioners. However, the validity of these estimation methods has not been extensively investigated. This is mainly because these datasets usually lack data about passengers’ alighting, as passengers are often required to tap their smart cards only when boarding a public transport service. Thus, this paper has two main objectives. First, the paper reports on the implementation and validation of the existing O–D estimation method using the unique smart card dataset of the South-East Queensland public transport network which includes data on both boarding stops and alighting stops. Second, the paper improves the O–D estimation algorithm and empirically examines these improvements, relying on this unique dataset. The evaluation of the last destination assumption of the trip-chaining method shows a significant negative impact on the matching results of the differences between actual boarding/alighting times and the public transport schedules. The proposed changes to the algorithm improve the average distance between the actual and estimated alighting stops, as this distance is reduced from 806 m using the original algorithm to 530 m after applying the suggested improvements.  相似文献   
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