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1.
Freight modal shift from road to rail is a potential means by which the negative environmental and social impacts of transport can be reduced. This paper explores recent supply chain changes and assesses their impacts on the mode choice decision-making process, specifically addressing the implications for the use of rail. Despite many of the identified changes effectively making the use of rail more difficult, considerable evidence has been found of the potential for rail to attract new traffic. Much of the identified potential is unlikely to materialise, however, without improvements in rail network capability and capacity and a greater customer focus from rail freight operators.  相似文献   

2.
Increasingly air transport growth raises the question of its impact on the environment. Public authorities and researchers are relying more and more on high-speed trains (HSTs), whose efficiency is supposed to lead to a modal shift from airplanes. However, most transport studies focus on the evolution of demand rather than supply, although it is basically the latter that determines environmental damage. In light of this fact, this paper aims to compare the overall dynamics in the supply of air transport in Europe compared to the HST supply and to examine empirically five city-pairs. The development of high-speed rail remains limited compared to the increase of air services. For a given city-pair, the decline in the number of flights depends on various conditions, including length of the HST journey and the strategies adopted by the airlines. Some carriers reduce their supply in terms of the number of seats but increase the number of flights in order to compete more effectively with the HSTs. Moreover, the competition between low-cost airlines and HSTs should be kept in mind and re-examined in a few years.  相似文献   

3.
This article deals with an analysis, modeling, and assessing performances of supply chains served by long-distance intercontinental intermodal rail/road- and sea-shipping freight transport corridor(s). For such a purpose, the supply chains are defined and the methodology for assessing their performances under given conditions is developed. The methodology consists of the analytical models of indicators of the operational, economic, environmental and social performances of particular corridors and corresponding supply chains assumed to be dependent on the infrastructural and technical/technological capabilities. The models of particular indicators have been applied according to “what-if” scenario approach to assessing performances of the long-distance intercontinental inland and maritime freight transport corridors spreading between China and Europe in the scope of the “Silk Road Economic Belt” and “A New Maritime Silk Road” policy initiative. The results prove that the intermodal inland rail/road alternative could act as a serious competitive alternative to its maritime deep-sea counterpart under given conditions. Nevertheless, in order to realize the opportunities, large investments in the inland rail/road infrastructure are required to appropriately connect China with Europe.  相似文献   

4.
The environmental impact of transport is a growing issue in transport infrastructure planning. The construction of a high-speed rail station at the Madrid Barajas Airport in Spain is an example of the integration of different transportation modes, with expected environmental benefits. We construct a model to assess modal choice and environmental benefits. The results show that with high-speed rail the number of people choosing air travel and the private car is reduced leading to important environmental benefits: a reduction of close to 5 kg of CO2 per passenger, or 10% of all emissions on the corridor. Our results also show that increasing the cost of using the private car is picked up by air transport rather than high-speed rail, leading to an increase in total emissions.  相似文献   

5.
Air-rail integration has become a popular idea to relieve airport congestion and environmental impact of transport industry, especially amid the fast expansion of high-speed rail network around the world. This study examines the circumstances under which air-rail integration can be better justified, by focusing on the effects of reducing air-rail connecting time on transport operators' profits, consumer surplus, and social welfare. We show that while consumers always benefit from less air-rail connecting time (an integrated hub with seamless transfer between air and rail services is always preferred by passengers), operators of the two modes, air transport and high-speed rail, won't have an incentive to integrate unless the cost of integration is sufficiently low. Nonetheless, reducing air-rail connecting time enhances total surplus when the hub airport suffers from a certain degree of capacity constraint and the cost of air-rail integration is not too high.  相似文献   

6.
This paper presents a supernetwork equilibrium model integrating supply chain networks with a transport network, namely, a supply chain-transport supernetwork equilibrium model. The model takes into account the behaviour of freight carriers and transport network users to endogenously determine the transport costs generated in the supply chain networks. The interaction between transport network and supply chain networks can also be examined. Results of the numerical tests reveal that the improvement of transport network could enhance the efficiency of supply chain networks. The paper makes contributions to modelling of supply chain networks as well as to that of transport networks.  相似文献   

7.
The decision-making process for planning new urban public transport systems in the UK is examined by studying 11 new and planned systems. The objectives of building the systems relate to transport and development issues. A number of key factors are taken into account during the decision-making process: forecast demand, image, deregulation of buses, technological innovation, private sector involvement and the funding mechanism. The requirement for proven technology and the forecast demand for the systems reduces the choice to one of light rail or bus. The effects of bus deregulation, funding and image, essentially reduce that choice to light rail or nothing. Cost should be kept low, which suggests a bus based system, but current legislation favours more expensive light rail systems. The conclusion is that although transport planners make rational decisions within the current political framework, the framework, and therefore some of the decisions, are not rational.  相似文献   

8.
Public transport in urban Australia is dominated by the automobile. As we approach the end of the 20th century, there is much renewed interest in revitalising urban public transport as one way of combating the increasing levels of traffic congestion, deterioration in air quality and global warming. This paper takes stock of the situation in Australia, identifying the challenges that the urban public transport sector faces in redressing the imbalance between car and public transport market share. Particular emphasis is given to the role of buses and busways in contrast to rail, and strategies to reduce the attractiveness of the car.  相似文献   

9.
Intermodal transport is the combination and integration of several transport modes (such as rail, inland waterways with road transport). In order to make the transhipment easy and efficient standard loading units are used, such as containers or swap-bodies. As for the main haul, more environmental friendly modes are used (rail and inland waterways) and a modal shift towards these modes can help in reducing the congestion. Therefore several policies are directed to stimulate the intermodal transport market.In this paper, a location analysis model for Belgian intermodal terminals (LAMBIT) is developed and used to assess different policy measures in Belgium. The simulations show that the different policy measures oriented towards the rail/road and inland waterways/road combinations should be incorporated in a coherent, integrated vision, in order to not create a modal shift between the different intermodal transport options. The methodology can easily be extended towards a European scale.  相似文献   

10.
This paper introduces conceptual and mathematical models of the domestic grain supply chain incorporating trucking, elevator storage, and rail transportation. We compare conventional rail service supported by country elevators with shuttle service supported by terminal elevators across three critical transportation service dimensions: travel time, cost, and capacity. Even after taking into account trucking and elevator storage, the time and cost model results indicate that shuttle service transports grain faster and reduces logistical supply chain costs, respectively, relative to conventional service. The rail capacity model results demonstrate that shifting grain from conventional to shuttle service significantly increases rail capacity.  相似文献   

11.
The optimal supply of rail and bus in low density areas is studied by calibrating a demand and supply model with three modes (car, bus and rail) to an existing low density corridor. Varying the length of the network, the frequencies and the size of the populations, allows to study the trade-off between the consumer surplus losses of the public transport users and the transit operation and maintenance costs savings. We find that for an existing rail network, the optimization of frequency is the prime source of welfare gains. The rail network is marginally beneficial in the sense that keeping the network is welfare improving as long as there is no major repair or replacement investment needed. When population in the smaller towns decreases strongly, it becomes welfare improving to close the existing rail network but a bus service remains beneficial for at least part of the network.  相似文献   

12.
At the European level there is an increasing focus on how freight transport can be moved from trucks on roads to more environmentally friendly modes such as rail and ship. A large proportion of the transport services between OD pairs, however, cannot be substituted since there is only one alternative available. The paper investigates the magnitude of this “structural inelasticity” of modal substitution in freight transport due to a sparser layout of rail and ship-based freight networks compared to road. In the analysis we use a recent Scandinavian freight demand model covering more than 800 zones. We find that the structural inelasticity is very significant - in particular for transportation over less than 500 km. Moreover, the inelasticity varies greatly with commodity groups and between OD pairs, and it depends strongly on the port and rail infrastructure. The results suggest that pure charging instruments (road pricing for trucks) in many regions will have limited mode substitution impacts. However, if combined with structural changes in terms of improved infrastructure for rail and ship, impacts may be greater.  相似文献   

13.
This paper identifies research opportunities which will enable the further integration of inland waterway transport in the intermodal supply chain. Intermodal transport may be interpreted as a chain of actors who supply a transport service. Inland navigation can play a crucial role in increasing supply chain service performance. A first group of research challenges lies in the evolving relationship between transport geography and logistics activities. The next set of research challenges has the objective to encourage efficient operations in IWT: development of a system wide model for IWT, integration of operational planning systems and analysis of bundling networks. A third group of research efforts is directed towards shippers and consignees who use the intermodal transport chain to send or receive their goods: further development of models that integrate intermodal transport decisions with supply chain decisions and creation of green supply chains. A fourth cluster of research challenges concerns the problem domain of external cost calculations. Finally detailed time series data on freight transport should be collected to support these future research tracks.  相似文献   

14.
牵引供电制式的选择对于轨道交通来说意义重大,介绍城市轨道交通供电系统组成.说明DC1500V与DC750V的不同特点,分析接触轨与接触网的不同。通过技术特点的比较.得出DC1500V架空接触网方式是最优方式,也将是轨道交通供电系统的发展方向的结论。  相似文献   

15.
The environmental impact of food transportation is site and product specific and depends on the direct relation between origin-to-destination distance and logistic efficiency, as pointed out by the relevant literature. This paper analyses a very specific case, comparing the impacts of transportation generated by the logistics of two brands of Italian canned tomato purchased in Sassari (Sardinia, Italy), one extending over the whole continental Italian territory, the other mainly located in the island of Sardinia. Different sale (supermarket chain vs. independent retailers) and shopping (foot vs. car) modalities are also considered. The contributions to global warming, local pollution and traffic congestion are considered.The case study shows that the logistics of the national brand is much more polluting than the regional, not only because of the longer distance between origin and destination, but also because the additional distance that is needed to reach logistic hubs is not compensated by higher load factors. Instead, the logistics of the regional brand is based on a very efficient point-to-point organization. This result is generalizable to all regional supply chains featuring high volumes of product. Results of the case study also depend on: a) the high impact of packaging transportation, because of the very low weight/volume ratio of empty cans; b) the high CO2 emission coefficient of lorries and trailers transportation by ferry (Ro–Ro). The case study also stresses the very high impact of shopping by car.  相似文献   

16.
Traditional methods of evaluation have not been very successful in accounting for non-transport benefits resulting from rail investments. But increasingly, these factors are becoming more important in well-developed transport networks, as the effects of additional links or capacity cannot be justified in transport terms alone. This paper brings together the evidence at three separate levels arguing that there are different impacts that must be investigated at different levels with appropriate methods. At the macroeconomic level, regional network effects can be identified, as can the impacts on the economy as measured through changes in output and productivity. At the meso level, the impacts relate more to agglomeration economies and labour market effects, with some additional network and environmental consequences. At the micro level, the impacts are determined by the land and property market effects. Examples of rail investment are given for each of the scales of analysis, and conclusions are drawn on the future directions and challenges for the quantification of both transport and non-transport benefits.  相似文献   

17.
Transport plays a critical role in facilitating competitiveness in post-industrial economies. High quality transport services and infrastructure enhance internal and external connectivity. This research examines published and unpublished evidence of economic impacts of modern light rail (tram and light metro) systems in the United Kingdom and globally. Evidence is considered relating outcomes of investment in light rail systems to: unlocking previously hard to reach sites for development; triggering fresh growth through elimination of significant transport constraints; stimulation of inward investment; extension of labour market catchment areas; reorganisation or rationalisation of production, distribution and land use; and land and property value increase and capture. Urban light rail investment can help regenerate Central Business Districts and boost employment and property prices. Similar rail investments in different locations may not however have the same economic impacts — geography matters. Other conditions in addition to transport investment are required for positive externalities.  相似文献   

18.
An increase in urban freight transport is inevitable as growing urban populations require more goods, more conveniently. A deeper understanding of the geography and trends of urban freight transport must recognise that it is the aggregate result of a complex web of supply chain interactions. To understand the trends, the behaviour of the underlying supply chains must be understood. Using Global Positioning System (GPS) traces of commercial vehicles and network theory concepts, this paper examines the characteristics of supply chain micro-communities in three urban areas in South Africa. The similarity in the structure of these micro-communities across the three, very diverse, areas suggests that the dynamics that drive supply chain interaction are not dependent on local geography. Four prominent archetypes were identified that account for more than half of the micro-communities in each area. Directionality, geographic dispersion and the balance of importance in the micro-communities are studied in the context of these archetypes. This paper presents a first puzzle piece in deducing urban freight transport patterns from supply chain interaction. Furthermore the results are an empirical benchmark that can validate theoretic models of urban supply chain interaction.  相似文献   

19.
Despite freight transport operations being influenced by supply chain dynamics, there has been only a very limited investigation into the impact of demand amplification on this function, with almost no analytical research. This paper aims, through spreadsheet simulation of a generic production control system, to quantify the impact of demand amplification on transport performance. Performance measures evaluated include both transport cost and efficiency. The results in general find a negative relationship between transport performance and demand amplification. It is also found that the ratio of vehicle capacity to average demand affects these results.  相似文献   

20.
A growing number of citizens are concerned about the environmental impact of air transport, and aviation has become synonymous with high carbon emissions and global warming, which has led to the development of flygskam (or flight shame) in Europe. While its impact on air traffic remains unclear, flight shame has forced the airline industry to react and better understand its origin. In this research, building on the growing literature on industry and organizational stigma, we assume that flight shame can be partly explained by a distorted public perception of the environmental impact of air transport. Accordingly, we investigate the level of knowledge of the environmental footprint of air transport. Based on a sample of 1018 French respondents, we reveal that more than 90% of respondents overestimate the share of air transport in global carbon emissions. We also show that 98% of the respondents underestimate the reduction in carbon emissions per passenger. Finally, we investigate the awareness of the measures taken by the industry to curb its carbon emissions and highlight, for instance, that 70% of respondents overestimate the fuel consumption of the newest generations of aircraft. Based on these results, we draw lessons for airlines and for the air transport industry to help cope with flight shame in Europe.  相似文献   

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