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1.
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   

2.
The demand for inland freight transport in Europe is mainly met by road transport, leading to unsustainable impacts such as air pollution, greenhouse gas emissions and congestion. Since rail transport has lower externalities than road transport, a modal shift from road to rail is an accepted policy goal for achieving a more sustainable and competitive transport system. However, intermodal road–rail transport is mainly competitive for long-distance transport, and as a consequence, the potential for modal shift is limited. The cost efficiency of road–rail intermodal transport is particularly sensitive to pre- and post-haulage (PPH) costs, since this activity typically has a larger cost compared with its share of the total distance in the transport chain. For intermodal transportation over shorter distances, for example, below 300 km and where there are substantial PPH activities at both ends of the chain, the competitiveness of the intermodal transport system compared with that of direct road is low. Improving the efficiency of PPH activities is, therefore, of utmost importance for the competitiveness of the intermodal transport system. This paper looks into the issue of improving the cost efficiency of an intermodal transport chain by implementing an innovative and flexible legal framework regarding the PPH activities in the chain. By extending the legal framework with exemptions for longer vehicles in PPH, the cost efficiency could be greatly improved. The purpose of such a framework is to allow and enable, for PPH exclusively, the use of 2?×?40 foot or even two semi-trailers using only one vehicle in the context of the Swedish regulatory framework. This paper develops a strategic calculation model for assessing and investigating the consequences of such a framework and investigates the framework's potential in terms of cost efficiency. The model in combination with a sensitivity analysis of input variables gives a comprehensive understanding of the effects of PPH under different circumstances. From the results, it is evident that there are substantial positive effects associated with a PPH framework of longer vehicles. Results indicate that a typical shipper may experience cost reductions of about 5–10% of the total costs of the intermodal transport chain. In summary, a more innovative and flexible legal framework regarding vehicle length in the PPH links can contribute to a greater modal shift, improved cost efficiency and more environmentally friendly transportation systems.  相似文献   

3.
This paper discusses the impact of three freight transport policies aiming to promote railroad intermodal transport in Europe, and examines the case of Belgium as a testing ground. These policies consist in subsidizing intermodal transport operations (such as in Belgium, to stimulate rail transport), internalizing external costs (as recommended by the European Union in order to foster cleaner modes), and adopting a system perspective when optimizing the location of inland intermodal terminals. The study proposes an innovative mixed integer intermodal freight location-allocation model based on hub-location theory and deals with non-linear transport costs in order to replicate economies of distance. Our analysis suggests that subsidizing has a significant impact on the volumes transported by intermodal transport, and, to a lesser extent, that optimizing terminal location increases the competitiveness of intermodal transport. On the other hand, according to our assumptions, internalizing external costs can negatively impact the promotion of intermodality. This finding indicates that innovative last-mile transports are needed in order to reduce the external impacts of drayage operations.  相似文献   

4.
This paper develops a model for calculating comparable combined internal and external costs of intermodal and road freight transport networks. Internal costs consist of the operational-private costs borne by the transport and intermodal terminal operators, and the time costs of goods tied in transit. The external costs include the costs of the impacts of both networks on society and the environment such as local and global air pollution, congestion, noise pollution, and traffic accidents. The model is applied to the simplified configurations of both networks using the inputs from the European freight transport system. The objective is to investigate some effects of European Union policy, which aims to internalise the external costs of transport, on the prospective competition between two networks from a social perspective.  相似文献   

5.
This paper develops a method for analysing and estimating savings in externalities that could be achieved by substituting truck with rail freight services in a given Trans-European freight transport corridor. The externalities affected include energy consumption, emissions of greenhouse gases, noise, congestion, and traffic incidents/accidents. The European Commission transport policy aims to provide an institutional framework for the medium- to long-term sustainable development of the transport sector. An important aspect of this policy is to stimulating the modal shift from truck to rail freight transport in inland Trans-European corridors.  相似文献   

6.
This paper is about distance and time as factors of competitiveness of intermodal transport. It reviews the relevance of the factors, evaluates time models in practice, compares network distances and times in alternative bundling networks with geometrically varied layouts, and points out how these networks perform in terms of vehicle scale, frequency and door-to-door time. The analysis focuses on intermodal transport in Europe, especially intermodal rail transport, but is in search for generic conclusions. The paper does not incorporate the distance and time results in cost models, and draws conclusions for transport innovation, wherever this is possible without cost modelling. For instance, the feature vehicle scale, an important factor of transport costs, is analysed and discussed.Distance and time are important factors of competitiveness of intermodal transport. They generate (direct) vehicle costs and – via transport quality – indirect costs to the customers. Clearly direct costs/prices are the most important performance of the intermodal transport system. The relevance of quality performances is less clarified. Customers emphasise the importance of a good match between the transport and the logistic system. In this framework (time) reliability is valued high. Often transport time, arrival and departure times, and frequency have a lower priority. But such conclusions can hardy be generalised. The range of valuations reflects the heterogeneity of situations. Some lack of clarity is obviously due to overlapping definitions of different performance types.The following parts of the paper are about two central fields of network design, which have a large impact on transport costs and quality, namely the design of vehicle roundtrips (and acceleration of transport speed) and the choice of bundling type: do vehicles provide direct services or run in what we call complex bundling networks? An example is the hub-and-spoke network. The objective of complex bundling is to increase vehicle scale and/or transport frequency even if network volumes are restricted. Complex bundling requires intermediate nodes for the exchange of load units. Examples of complex bundling networks are the hub-and-spoke network or the line network.Roundtrip and bundling design are interrelated policy fields: an acceleration of the roundtrip speed, often desirable from the cost point of view, can often only be carried out customer friendly, if the transport frequency is increased. But often the flow size is not sufficient for a higher frequency. Then a change of bundling model can be an outcome.Complex bundling networks are known to have longer average distances and times, the latter also due to the presence of additional intermediate exchange nodes. However, this disadvantage is – inside the limits of maximal vehicle sizes – overruled by the advantage of a restricted number of network links. Therefore generally, complex bundling networks have shorter total vehicle distances and times. This expression of economies of scale implies lower vehicle costs per load unit.The last part of the paper presents door-to-door times of load units of complex bundling networks and compares them with unimodal road transport. The times of complex bundling networks are larger than that of networks with direct connections, but nevertheless competitive with unimodal road transport, except for short distances.  相似文献   

7.
This paper presents the impact of fuel price increases on the market area of intermodal transport terminals. Aim of this research is to determine whether an increase in fuel prices is sufficient enough to raise the market area of intermodal transport to the same degree that would be accomplished by stimulating intermodal transport through policy instruments. Therefore, several fuel price scenarios are analysed in order to verify the impact of different fuel price evolutions on the market area of unimodal road transport compared to intermodal transport in Belgium. The LAMBIT-model (Location Analysis for Belgian Intermodal Terminals), which is a GIS-based model (Macharis and Pekin, 2008), is used to analyse the different fuel price increases and enables a visualisation of the impact on the market area. The LAMBIT model incorporates the different network layers for each transport mode by setting up a GIS network that includes four different layers: the road network, the rail network, the inland waterways network and the final haulage network. The geographic locations of the intermodal terminals and the port of Antwerp are added as nodes in the network and the Belgian municipality centres are defined and connected to the different network layers. Based on the different fuel price scenarios representing respectively a fuel price increase with 10% (low price case), 50% (business as usual case) and 90% (high price case), the results of the LAMBIT model show that the market areas rise in favour of intermodal barge/road and intermodal rail/road. Depending on the scenario, the degree of modal shift however differs. Additionally, in order to compare policy measures with the effect of a fuel price increase, the internalisation of the external costs is analysed with the LAMBIT model. For some years, the European Commission is supporting the idea that transportation costs should reflect the true impacts on environment and society, and is relentlessly pushing towards the so called ‘internalisation of external costs’ as a policy instrument in order to establish fair and efficient pricing of different transport modes. This requires monetarizing the external effects of transport and adding them to the already internalized costs in order to give the correct price signals. Results of this comparative analysis performed with the LAMBIT model are also presented in this paper.  相似文献   

8.
9.
Complexity in transport networks evokes the need for instant response to the changing dynamics and uncertainties in the upstream operations, where multiple modes of transport are often available, but rarely used in conjunction. This paper proposes a model for strategic transport planning involving a network wide intermodal transport system. The system determines the spatio-temporal states of road based freight networks (unimodal) and future traffic flow in definite time intervals. This information is processed to devise efficient scheduling plans by coordinating and connecting existing rail transport schedules to road based freight systems (intermodal). The traffic flow estimation is performed by kernel based support vector mechanisms while mixed integer programming (MIP) is used to optimize schedules for intermodal transport network by considering various costs and additional capacity constraints. The model has been successfully applied to an existing Fast Moving Consumer Goods (FMCG) distribution network in India with encouraging results.  相似文献   

10.
Intermodal rail/road transportation is an instrument of green logistics, which may help reducing transport related greenhouse gas (GHG) emissions. In order to assess the environmental impact of road and rail transports, researchers have formulated very detailed microscopic models, which determine vehicle emissions precisely based on a vast number of parameters. They also developed macroscopic models, which estimate emissions more roughly from few parameters that are considered most influential. One of the goals of this paper is to develop mesoscopic models that combine the preciseness of micro-models while requiring only little more information than macro-models. We propose emission models designed for transport planning purposes which are simple to calibrate by transport managers. Despite their compactness, our models are able to reflect the influence of various traffic conditions on a transport’s total emissions. Furthermore, contrasting most papers considering either the road or the rail mode, we provide models on a common basis for both modes of transportation. We validate our models using popular micro- and macroscopic models and we apply them to artificial and real world transport scenarios to identify under which circumstances intermodal transports actually effect lower emissions. We find that travel speed and country-specific energy emission factors influence the eco-friendliness of intermodal transports most severely. Hence, the particular route chosen for a transnational intermodal transport is an important but so far neglected option for eco-friendly transportation.  相似文献   

11.
Transport demand for containers has been increasing for decades, which places pressure on road transport. As a result, rail transport is stimulated to provide better intermodal freight transport services. This paper investigates mathematical models for the planning of container movements in a port area, integrating the inter-terminal transport of containers (ITT, within the port area) with the rail freight formation and transport process (towards the hinterland). An integer linear programming model is used to formulate the container transport across operations at container terminals, the network interconnecting them, railway yards and the railway networks towards the hinterland. A tabu search algorithm is proposed to solve the problem. The practical applicability of the algorithm is tested in a realistic infrastructure case and different demand scenarios. Our results show the degree by which internal (ITT) and external (hinterland) transport processes interact, and the potential for improvement of overall operations when the integrated optimization proposed is used. Instead, if the planning of containers in the ITT system is optimized as a stand-alone problem, the railway terminals may suffer from longer delay times or additional train cancellations. When planning the transport of 4060 TEU containers within one day, the benefits of the ITT planning without considering railway operations account for 17% ITT cost reduction but 93% railway operational cost growth, while the benefits of integrating ITT and railway account for a reduction of 20% in ITT cost and 44% in railway operational costs.  相似文献   

12.
To achieve transport cost reductions and to reduce the environmental impact of road transport, different European countries are allowing or testing longer and heavier vehicles on their road network. In Belgium, the Flanders region started a trial in 2015 allowing a limited number of longer and heavier vehicles on a selection of approved routes. A concern among intermodal operators is however that an allowance of longer and heavier vehicles could trigger a reverse modal shift away from rail and inland waterways container transport. Starting from experiences in other European countries, this paper discusses the potential spatial impact of allowing longer and heavier vehicles on the market areas of intermodal transhipment terminals using a geographic information systems-based location analysis model. In a second step, external transport costs are incorporated in this model, to quantify the spatially diversified societal costs of a potential reverse modal shift.  相似文献   

13.
Abstract

Rail freight has been generally in decline in many European Union countries in recent years, contrary to European transport policy. State support for railway operations is commonplace in most countries, and this paper establishes the background to targeted rail freight grant funding in Britain. Through desk‐based analysis of Freight Facilities Grant (FFG) awards, together with a survey of recipient companies, the paper assesses the extent to which the planned flows expected from these awards have materialized and it evaluates the role of the grants in influencing rail freight volumes. The evidence suggests that FFG funding has been largely successful, attracting considerable private sector investment. Overall, FFGs have played an important role in developing or retaining rail freight flows, although the processes could be made more transparent and consistent. As other European countries liberalize their rail freight markets as a result of European Union legislation, such targeted funding may be an appropriate alternative to more general government subsidy of freight operations.  相似文献   

14.
As the interface point between road and rail, intermodal freight terminals (IFTs) are critical elements in the total freight distribution chain. This paper addresses the twin objectives of reducing freight transport costs and improving customer service by putting forward a number of indicators designed to measure the performance of IFTs. Each of the three major performance areas, namely customer service, operational efficiency and terminal productivity are discussed in detail.

A methodology is put forward which enables operating strategies to be evaluated. Computer simulation is used in order to arrive at strategies which reduce operating and capital costs and satisfy customer service requirements. The simulation model outputs include performance measures related to customer service such as mean waiting times required for loading and unloading of containers, as well as productivity measures of terminal operations such as lifting equipment utilisation.  相似文献   

15.
Intermodal freight transport has developed into a significant sector of the transport industry in its own right. This development has been followed by an increase in intermodal freight transportation research. We contend that a new transportation research application field is emerging; and that, while still in a pre-paradigmatic phase, it is now time to move on to a more mature independent research field. An independent research field can be justified because intermodal transport is a complex system that has characteristics which distinguishes it from other transport systems. We have reviewed 92 publications in order to identify the characteristics of the intermodal research community and scientific knowledge base. This paper will discuss aspects of this research, assessing the status quo and seeking directions for the future. To conclude, we will propose an intermodal research agenda which can direct the intermodal research field towards a period of “normal science”.  相似文献   

16.
Environmental issues have received a prominent place in transport policies of most European countries. The coordination of such policies however, is fraught with many difficulties. The increasing freight flows after the European integration are a source of concern, but have not yet led to straightforward and effective environmental strategies.The paper focuses on the Trans Alpine freight transport systems in the light of the future integration of single national transport systems into the European transport network. The environmental, social and institutional peculiarities of this ‘region’ have favoured—in the past—the development of strong nationally-oriented policies, partly in contrast with the goals promoted by the European Union. The present analysis aims to highlight opportunities, and limits inherent, in the implementation of various infrastructure projects oriented towards a drastic change of the Alpine transport systems structure. The Alpine countries, viz. Austria and Switzerland, play a central role in the promotion of environmental benign modes of transport of goods, with a clear focus on rail. The route choice and modal split of freight flows in Europe are taking place simultaneously. In this paper the results of European freight flow models (based on logit analysis and neural networks) will be presented. An important exercise is then to assess the consequences of various types of eco-taxes on road transport in Europe. In this context, several policy scenarios will be dealt with.  相似文献   

17.
步晓庆 《综合运输》2021,(1):104-109
在"一带一路"战略背景下,铁路物流中心的公铁联运业务至关重要。公铁联运业务各主体的协同存在易变性,资源双方是否信任会影响各自的策略选择。本文以铁路运输企业为主导,铁路运输企业接到客户公铁联运订单时会借助平台发布公路运输需求信息,公路运输企业根据自身情况向铁路运输企业表达意愿,最后铁路运输企业根据其采取的策略找到自身是否接受合作的均衡条件。本文通过对公、铁运输企业的短期博弈分析,找到双方合作的均衡条件,为双方利益分配奠定基础。  相似文献   

18.
The recent European regulations on emissions from heavy duty vehicles (Euro VI) along with the enforcement of ECA regulations have represented an additional challenge for the sustainability of the motorways of the sea. The main aim of this paper is to identify the optimal sizing and the most adequate propulsion plant for a fleet of feeder vessels that, by operating under motorways of the sea conditions, is able to articulate competitive intermodal chains versus the road for the door-to-door transport by ensuring the sustainability of the intermodality in the current normative framework. Thus, a mathematical model is developed to evaluate, aside from the total costs and the time invested in the transport, the environmental costs of the unimodal transport and of intermodal chains with different sizing and technologies for the vessels. The resolution of this multiobjective model was carried out with an NSGA-II algorithm in an application to a transport network between Spain and France. This application concluded that fast and small vessels with LNG propulsion plants are the most convenient to maximize the competitiveness advantage against the road alternative. Likewise, the analysis of the environmental performance of both transport systems in the application case from 2010 to 2015 shows an unfavourable environmental evolution for the intermodality.  相似文献   

19.
Freight transport industry plays a significant role in boosting economic growth, while also creating many negative externalities for social welfare and the environment. Using data from 1997 to 2017, this study employs the complete decomposition technique to identify the driving forces of freight transport and explores its internal relations with economic growth in China. The decomposition analysis focuses on four factors that are responsible for freight transport: economic activity, industrial structure, transport intensity, and haulage distance. Then, the decoupling index is adopted to examine the decoupling relationship between freight transport and economic growth in China. The results showed that weak decoupling between freight transport and economic growth was the main state during the study period. A strong decoupling effect was identified in 1997–1998, 2012–2013, and 2014–2015, whereas no decoupling effect was observed in 1998–1999, 2008–2009, and 2011–2012. The transport intensity was the most important contributor to the decoupling progress, the industrial structure effect played a role in promoting the decoupling progress over half of the years during the research period, and the haulage distance effect facilitated the decoupling progress in more than one-third of the years examined.  相似文献   

20.

Intermodal road-rail freight transport works best within markets with relatively large flows occurring over long distances, which corresponds poorly to the current demand for transport in the European Union. The purpose of this paper is to compare the capabilities of conventional European intermodal transport, with special reference to the competitiveness in markets with small flows over short distances, and to explore innovative concepts. Using a technological systems approach, key functions are identified as being the inducement and blocking mechanisms that affect the development and diffusion path of this 'small flows over short distances' (SFSD) system, providing a tool for empirical delineation of the system. These concepts are illustrated and analysed through a case study of the Swedish development project Light-combi. The results show that market and financial uncertainties, insufficient network connectivity and policies favouring the existing technology paradigm, severely hamper the development and diffusion of SFSD systems.  相似文献   

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