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1.
A number of states have placed high-speed rail service on their institutional agendas in recent years. Analysis of why some states have been giving serious consideration to the possibility of high-speed rail service while other states have not examined economic and political forces, as well as the transportation problem environment and established transportation commitments. States paying serious attention to high-speed rail service tend to have large populations and large land areas, two of the most fundamental aspects of the transportation task environment.  相似文献   

2.
Intermodal rail/road transportation combines advantages of both modes of transport and is often seen as an effective approach for reducing the environmental impact of freight transportation. This is because it is often expected that rail transportation emits less greenhouse gases than road transportation. However, the actual emissions of both modes of transport depend on various factors like vehicle type, traction type, fuel emission factors, payload utilization, slope profile or traffic conditions. Still, comprehensive experimental results for estimating emission rates from heavy and voluminous goods in large-scale transportation systems are hardly available so far. This study describes an intermodal rail/road network model that covers the majority of European countries. Using this network model, we estimate emission rates with a mesoscopic model within and between the considered countries by conducting a large-scale simulation of road-only transports and intermodal transports. We show that there are high variations of emission rates for both road-only transportation and intermodal rail/road transportation over the different transport relations in Europe. We found that intermodal routing is more eco-friendly than road-only routing for more than 90% of the simulated shipments. Again, this value varies strongly among country pairs.  相似文献   

3.
An analytical model that determines the optimal location and length of rail line along a crosstown transportation corridor with the objective of minimizing the total transportation cost is presented. A general, many-to-many passenger demand pattern is considered. The objective function, which includes the rail and bus riding costs, rail and bus operating costs, rail fleet costs and rail line costs, is minimized by using the classical optimization method with the aid of a computer program developed for the model. The model is applied to the Northwest-South transportation corridor in Calgary, Alberta, and the sensitivity of the optimal rail line location and length to the unit cost and demand parameters at their reasonable ranges is tested. It is found that although the total passenger demand, unit rail line cost, and unit bus operating cost have greater influence than the unit bus and rail riding costs, and unit rail fleet and operating costs, the optimal line length is generally insensitive to all these parameters. It is also found that the length of the existing LRT line in the corridor is comparable to the optimal line length obtained from the model, but the existing line should be extended further south in order to meet the heavier demand in that direction optimally.  相似文献   

4.
新建轨道交通系统作为一种重要的公共交通工具,正在得到越来越广泛的应用。介绍了伦敦新建轨道交通系统——Tramlink的线路、车辆、运营管理、客流及特点等内容。作为地铁系统的补充,Tramlink在伦敦公共交通领域发挥着重要的作用。  相似文献   

5.
章娅琳  贺政纲  廖伟 《综合运输》2021,(2):99-104,115
高铁货运逐渐兴起,本文对货运动车组开行方案优化进行了研究。针对高铁运输安全、快捷、运输成本较低等特性,提出以货运动车组及客货混编动车组为主,客运动车组捎带运输为补充的开行模式,结合运输需求、线路通过能力等限条件,以运输成本最小和货主满意度最大为目标,建立多目标综合优化模型,运用线性加权组合法,以lingo软件为依托进行求解。通过算例给出具体开行方案,并对同一运输区间各种运输方式的单位成本及用时进行对比分析。结果表明,相对于传统运输方式,高铁货运综合运输成本较低,用时更短,能够兼顾运输企业与货主的双重要求;所建模型优化效果明显,可为未来货运动车组的开行提供参考。  相似文献   

6.
This paper describes two types of rail transportation problems in detail. These are train routing and makeup, and empty car distribution problems. Some of the recent optimization models which address these problems are reviewed and the areas for potential improvements in rail transportation literature are identified. The type of interactions which exist between routing, makeup, and empty car distribution decisions are highlighted and potential areas for future research are identified.  相似文献   

7.
The deficiencies in the Istanbul transportation system have led the local authorities to plan several alternative transportation projects. In this paper three alternative rail transit network proposals are evaluated by using Analytic Hierarchy Process (AHP), a multiple criteria decision support system. The AHP facilitates decision-making by organizing perceptions, experiences, knowledge and judgments, the forces that influence the decision, into a hierarchical framework with a goal, scenarios, criteria and alternatives of choice. Based on this analysis, the decision makers have developed a new alternative as a combination of the most closely competing two alternative rail transit networks. This combination rail transit network is currently under construction.  相似文献   

8.
This research empirically evaluates the public sector investment in the US freight transportation infrastructure. In particular, the infrastructures to support the two most comparable modes of freight transportation – highway and intermodal rail – are examined as alternatives for public fund allocation. Indicators for public sector transportation infrastructure investment mix are established based on financial analysis of both private and social costs and benefits, as well as the propensity of freight shippers to utilize such infrastructures. The research results in recommendations for the aggregate allocation of public funds in the US based on these indicators. We find that approximately a quarter of truck freight could be handled at a 25% lower cost if rail infrastructure to support it existed. Because an additional 80% reduction in social costs could be achieved through this modal conversion, the public sector is a critical participant in creating a more efficient transportation infrastructure.  相似文献   

9.
We use social-eco-efficient analysis in the form of SEEbalance to evaluate gravel transport sustainability for trucking and two kinds of intermodal transportation. Results show that switching from trucks to intermodal transportation can improve the sustainability of gravel transportation in the northeast corridor of Taiwan. Sensitivity analysis shows that rail combined with truck intermodal transportation has competitive advantage despite the terminal’s location factor.  相似文献   

10.
An intermodal transportation terminal is a facility that provides commuters with easy transfer between transit modes and providers such as buses, light rail, subway, taxis, airport shuttles, and commuter rail. The probability of a passenger transferring from one mode to another and the estimation of total transfer demand are of great importance to both practitioners and researchers when determining optimal design alternatives as well as the best control and management policies for daily operation of the terminal. This article presents a study that uses an entropy-based optimization approach to estimate the transfer demands between the available transportation modes in an intermodal transportation terminal. The development and calibration of the entropy model is presented in the first part of the article, which is followed by a case study of the SiHui Intermodal Terminal in Beijing, China.  相似文献   

11.
随着湘桂高铁、贵广高铁、南广高铁、云桂高铁的建成,广西逐步进入高铁时代。广西高铁的发展给广西北部湾港口群带来了新的生机,高铁与港口货物联运是未来广西北部湾港口物流发展的新趋势。文章分析了广西港口与高铁联运的有利条件以及高铁运输对港口物流的促进作用,从技术标准缺乏、货物分运混乱、物流成本偏高等方面阐述了港口与高铁联运存在的现实问题,并提出了相应对策。  相似文献   

12.
城市轨道交通具有安全舒适、快速环保、运能大和耗能少的特点,已经成为解决大城市交通拥堵问题的首选措施。文章从设计选型的角度出发,对噪声控制型、环境振动控制型和景观美化型这三类典型轨道结构型式的使用特点和效果进行了阐述,并分析了选型设计中应该注意的问题。  相似文献   

13.
The end of the cold war and confrontational politics of the eastern and western worlds have raised the possibility that resources formerly targeted toward military systems and options may be turned towards global lifestyle improvements [OTA, 1993]. Transportation has been one of the fields proposed as a likely candidate for both improvements and jobs. It is not possible to address economic development in the context of all transportation in one essay. For this reason I am only addressing the issues of economic development associated with mass transportation characteristic of urban and interurban environments. Realigning former defense resources to mass transit requires careful consideration of market conditions. According to economic survey data published by the Economic Roundtable in Los Angeles, there are currently less than 40,000 manufacturing jobs in the U.S. rail transportation industry [Drayse, 1993]. The same survey pointed out a severe mismatch between the skill base required by the rail industry and available defense technology resources. There exists no large base of unsatisfied demand in the rail market, therefore development of a large number of jobs is not likely if the approach is simply to introduce additional competing resources into a traditional market [Monitor, 1993].  相似文献   

14.
This study investigates the impact of high-speed rail investment on the economy and environment in China using a computable general equilibrium (CGE) model. The analysis is implemented in a dynamic recursive framework capturing long-run capital accumulation and labor market equilibrium. A national level impact was simulated through direct impact drivers including land use conversion, output expansion, cost reduction, productivity increase, transport demand substitution and induced demand. The results suggest that rail investment in China over the past decade has been a positive stimulus to the economy, while the effect on CO2 emissions generation has been large. Overall, the economic impacts of rail investment are achieved primarily through induced demand and output expansion, whereas the contribution from a reduction of rail transportation costs and rail productivity increases were modest. In addition, negligible negative impacts were found from land use for rail development and the substitution effect among other modes. Emissions reduction from substitution of rail for other modes was small and offset by output expansion due to lowered rail transport costs and induced demand.  相似文献   

15.
This paper estimates the total embodied energy and emissions modal freight requirements across the supply chain for each of over 400 sectors using Bureau of Transportation Statistics Commodity Flow Survey data and Bureau of Economic Analysis economic input-output tables for 2002. Across all sectors, direct domestic truck and rail transportation are similar in magnitude for embodied freight transportation of goods and services in terms of ton-km. However, the sectors differ significantly in energy consumption, greenhouse gas emissions, and costs per ton-km. Recent pressure to reduce energy consumption and emissions has motivated a search for more efficient freight mode choices. One solution would be to shift freight transportation away from modes that require more energy and emit more (e.g., truck) to modes that consume and emit less (e.g., rail and water).Our results show there are no individual sectors for which targeting changes would significantly decrease the total freight transportation energy and emissions, therefore we have also looked at the prospect of policies encouraging many sectors to shift modes. There are four scenarios analyzed: (1) shifting all truck to rail, shifting top 20% sector mode choice, (2) based on their emissions, (3) based on a multi-attribute analysis, and (4) increasing truck efficiency (e.g., mpg). Increasing truck efficiency by 10% results in similar energy and emissions reductions (approximately 7% for energy and 6% for emissions) as targeting the top 20% of sectors when selected based on emissions, whereas selecting the top 20% based on availability to shift from truck results in slightly less reductions of energy and emissions. Implementing policies to encourage higher efficiency in freight trucks may be a sufficient short term goal while efforts to reduce truck freight transportation through sectoral policies are implemented in the long term.  相似文献   

16.
Noise is an important externality of transportation systems in most countries in the modern world. Yet, there is a dearth of studies questioning the institutional structure and prevailing regulatory approach to transportation noise. An analysis of the Israeli situation identifies encroachment of residential areas on transportation facilities as a major source of noise-related conflicts. A noise rights approach is suggested to address this problem, and applied to the Israeli case, based on the existing institutional structure there. The applicability of the noise rights approach to other contexts and to air and rail transportation is also discussed.  相似文献   

17.
The current situation of suburban rail services is reviewed. Differences between seemingly similar services—urban transit, commuter service, suburban rail service and regional rail -are discussed. The suburban rail commuter is described as the true intermodal traveler. Differences of the political backgrounds of the inner-city compared to the suburbs complicate implementation of programs to improve service and suggest deep problems over the long term. Because the transition of suburban rail service from the private to public sector has been so recent, it is difficult for many to recognize that the profit of the service is in the lower total transportation costs for the community as compared to a cash dividend. Existing railroad lines in many cities have the potential of being a cost-effective solution to traffic problems, although the specific solutions vary widely, ranging from the operation of new commuter trains over the lines of a heavy duty railroad (Toronto) to a completely new light rail system (San Diego).  相似文献   

18.
Recent earthquake disasters have caused major damage to transportation networks, leading to significant economic disruption. While this suggests the need to evaluate total system performance in transportation risk assessment, in addition to examining the vulnerability of individual components such as bridges, no appropriate measures currently exist. This paper develops post-disaster system performance measures and applies them to the urban rail and highway transportation systems in the Kobe, Japan, region devastated by the 1995 Hyogoken–Nanbu earthquake. Performance is evaluated in terms of network coverage and transport accessibility. Performance degradation was much more severe for highways and railways than for other lifeline infrastructure systems. Both transportation systems fared poorly in the disaster but service restoration proceeded much more rapidly for rail. The restoration of highway system performance correlated closely with the recovery of highway traffic volumes. The paper further develops a measure of subarea transport accessibility and applies this to Kobe’s constituent city wards. Results indicate substantial spatial disparity that is maintained throughout the restoration period. Comparisons with the 1989 Loma Prieta and 1994 Northridge earthquakes in the US show that although these disasters caused notable damage to highway bridges, system performance degradation was small in comparison with the Kobe experience. The paper argues that explicitly measuring transportation system performance can greatly facilitate both understanding the effects of historic disasters and preparing for future hazard events.  相似文献   

19.
This paper analyses the performance of freight transportation modes in Brazil – namely air, water, rail and road – from February 1996 to August 2012 by investigating their long memory properties using fractional integration and autoregressive models on monthly tonnage data. Two important features are analysed: the degree of dependence of transportation traffic across time and its seasonal structure over the period. Furthermore, the stability of parameters across the sample period is investigated, incorporating potential structural breaks in the data, which describe discontinuity in freight transportation traffic. Some policy implications are derived.  相似文献   

20.
Los Angeles is well known around the world as an automobile-oriented low density community, yet recent transportation policies have emphasized greater capital investment in rail transportation than in highways, and recent policies have attempted to discourage automobile usage through transportation demand management. While these policies have accomplished small shifts toward public transport and somewhat lower dependence upon singly occupied automobilies for work commuting, the financial costs of these policy changes has been very large in relation to their benefits. Proper pricing of transportation alternatives, more creative use of new and emerging transportation technologies, and the provision of many more opportunities for simpler private sector transport services, would all appear to be more promising as cost-effective approaches to coping with congestion in Los Angeles than the current regional transportation policies.  相似文献   

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