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1.
Following the example of maritime transport, the relocation of fleets abroad – referred to as flagging out – has become an important cost reduction strategy for road freight transport companies. Particularly after the EU Eastern Enlargement in 2004, many Austrian road freight transport companies took advantage of both the freedom of services and the lower costs in New Member States. This paper shows the results of four waves of surveys of Austrian road hauliers, describing developments, attitudes, motives and impacts of the phenomenon. There is also a discussion about the significance of the problem, which was seldom referred to in the scientific literature.  相似文献   

2.
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   

3.
The objective of this work is the specification, calibration and validation of a route choice model distinguishing the phases of set perception and route choice among the alternatives belonging to the chosen set. Route generation is performed with a selective multi-criteria approach; route choice is performed using random and fuzzy utility models. As regards the fuzzy utility models, a new specification of a fuzzy model is introduced. Random and fuzzy utility models are compared and applied on a test road network and were specified and calibrated for national road freight transport on a real Italy-wide network.  相似文献   

4.
《Transport Policy》2007,14(1):39-48
In recent years many European countries have seen a decoupling of the growth in road freight traffic (vehicle kilometres) from economic growth. A similar decoupling has not been observed in road freight transport (tonne kilometres). In this paper the historical growth in national Danish road freight traffic and transport is attributed to causes using a Divisia index decomposition method. It is demonstrated that overall road freight traffic growth is a consequence of often opposite pointing growth effects in the underlying factors. The observed decoupling of road freight traffic growth from economic growth is mainly the result of use of larger vehicles, increasing average loads, and less empty running. Growth in road freight transport is primarily caused by growth in production. A decrease in the number of tons lifted per tonne produced (the handling factor) is offset by an increase in the tonne kilometres per tonne lifted.  相似文献   

5.
This paper introduces an Agent based modelling approach to model inter-urban freight transport between two or more trading regions. The use of the model is to ascertain the modal share of competing transport modes (road and intermodal) while taking complex transport service supply–demand dynamics into account. It is structured by modules describing company generation, supplier choice, modal competition and International road freight transport market dynamics. The behaviour of individual actors is simulated using normative agent behaviour and market knowledge. Using the micro-simulation approach, shippers and carriers (primarily road hauliers and a maritime based intermodal operator) interact through simulated contracts resulting in the generation of tours. The service performance of the tours is fed back into the model for decision making during contract deliberations. Preliminary application of model to Mediterranean case study show that market share gains of around 25–30% are obtained with policy interventions of financial subsidies to intermodal services and more frequent shipping services in the intermodal transport respectively.  相似文献   

6.
Road planning practice relies almost exclusively on parameters related to traffic factors, such as private vehicle speeds and volumes. In many developing countries the requirements for public transport and non-motorised transport are not explicitly integrated into the planning process, despite the fact that these form the primary mode of transport for the majority of the population. This affects the mobility opportunities for these sectors of the population and contributes to poor road safety, especially with regards to pedestrians. The research outlined in the paper posits that, in order to assess the usage and needs of the road holistically, other factors related to the adjacent land uses, socio-economic characteristics of the population the road serves, and the environmental context within which the road is located, factors heavily in how the road is used and should, therefore, be considered within the planning process. The paper describes a methodology to include these factors in the planning of roads. The method attempts to prioritise amongst the five primary road based modes (public transport, car, freight, walking and cycling) based upon a combination of traffic and non-traffic factors. The method employed uses a geographic information system (GIS) based spatial multiple criteria evaluation (SMCE) model with inputs from widely available data sources such as census, household travel surveys, land use and environmental data to arrive at solutions for modal priorities. A case study is conducted along an arterial route in Cape Town, South Africa, providing infrastructure planning recommendations and audit possibilities for the future. Since weighting is an important driver in the SMCE process, a sensitivity analysis is conducted to investigate the effect of alternative weighting schemes on the outputs from the method.  相似文献   

7.
This paper suggests a flexible decision support framework for the strategic planning of a freight transport hub network in Greece. The proposed methodology treats practical aspects related to the optimal number, location and geographical covering of hubs, through the network analysis of interregional trade, based on original survey data for road freight flows during 2004–2012. The results offer insights into the hierarchical structure of the network and related investment priorities, as the hub role of a prefecture is found to be strongly influenced by high population densities and manufacturing specialization, and its location along highway corridors.  相似文献   

8.
Due to the burgeoning demand for freight movement in the era of e-commerce, freight related road safety threats have been growing in both urban and suburban areas, despite the improved general traffic safety over the past decades. The empirical evidence on how freight trucks related crashes are distributed across neighborhoods and correlated to spatially varying factors is, however, highly limited. This article uses data from the Los Angeles region in 2018 to analyze the spatial patterns of freight trucks related traffic crashes and examines the major factors that contribute to those patterns using spatial econometric models. Maps show that freight trucks related crashes are highly associated with major freight generators but less clustered than the overall traffic crashes. Results from the spatial Durbin model indicate that access to freight generators, economic attributes, land uses, road infrastructure, and road network variables all contribute to the spatial distribution of freight trucks related crashes. The findings could help transport planners understand the dynamics of freight trucks related traffic safety and develop operational measures for mitigating the impacts of growing goods movement on local communities.  相似文献   

9.
In this paper we use discrete choice data to analyze asymmetries in the preference for freight transport attributes. A reference dependent utility specification allowed us to test for the existence of substantial asymmetries in perception of the transport cost. Hence, the re-estimation of our models in the WTP/WTA space helped us to quantify significant discrepancies between the WTP and WTA for the attributes included in the choice experiment, namely transit time, service frequency and delays in delivery time. Results are deemed essential to define alternative services to road capable to attract substantial volumes of freight.  相似文献   

10.
An efficient and effective freight transport strategy can be aided by early professional contributions from key stakeholders. One broad group who have historically been given limited opportunity to influence the drafting of a freight strategy, are commercial road users and shippers who manufacture and distribute goods. Utilising a data set collected in Australia in 1996 from a sample of organisations involved directly and indirectly in road freight transportation, views were sought on road infrastructure changes, new road infrastructure, non-road infrastructure needs and transport policies. An optimal scaling approach using non-linear canonical correlation is implemented to search for structural relationships between the underlying policy and infrastructure dimensions and the various industry categories. This framework provides a powerful mechanism for identifying differences among stakeholders in terms of their support for or opposition to specific policies. Results reveal the considerable differences in attitudes associated with the component parts of the freight industry.  相似文献   

11.
The main contribution of this paper is a new approach to evaluate and compare the freight accessibility conditions offered in a set of regions or cities. The key innovation of this approach lies in that it combines (statistical) centrality and reliability measures of accessibility, thus tackling one of the weaknesses that researchers have identified in the vast accessibility literature. The proposed approach is first explained in details for a hypothetical setting, and then is applied to Iran using data collected in the latest transport survey conducted in this country. The focus is placed on road transport, by far the dominant freight transport mode in Iran. The results obtained through this application provide clear insights into the relative positions of the main freight production and attraction zones of Iran with respect to road accessibility conditions, and therefore valuable information to assist transport authorities in their decisions regarding the evolution of the country's road network.  相似文献   

12.
This paper aims to contribute towards the design of effective freight transport policy by means of empirical analysis. In order to do so, a stated preference survey is undertaken to model the modal choice between door-to-door road transport and short sea shipping in the Motorway of the Sea of south-west Europe. The proposed analysis will provide policymakers with the necessary tool to identify the critical areas that should be addressed by future policy action in order to boost short sea shipping on Spain's Mediterranean coast. By applying the proposed method, we will be able to obtain estimates of the subjective values of transport attributes – value of time, value of reliability and value of frequency – in freight transport, values for which barely any empirical evidence on a national scale exists. Quantifying such values is a key part of the cost benefit analyses performed when evaluating transport projects.  相似文献   

13.
This paper discusses the negative impacts of freight transport growth, especially in and around urban areas. Over time, a growing number of road freight vehicles have delivered less freight over longer distances, while average load factors have been reduced. This development is unsatisfactory, as transport capacity that could have been used more efficiently is lost. To mitigate negative impact, it has been suggested that freight consolidation and better planned localisation of freight consolidation centres (FCCs) would improve city logistics. Based on primary data, this paper investigates the potential to establish urban FCCs intended for small road hauliers (SRHs) delivering goods to the retail sector in a wider geographical area, the Gothenburg region in Sweden. While the findings show that a large majority of SRHs could reach potential FCC locations in a short time, congestion affects deliveries and several factors, many of which were observed already in the 1970s, restrict FCC establishments. Under present conditions, there is little scope for SRHs to successfully deliver goods to retailers in the Gothenburg region from FCCs; therefore, a more efficient urban transport system from a business or societal perspective is unlikely. Policy makers need to take into consideration the different segments, requirements, and characteristics of different cities before venturing into costly FCC projects.  相似文献   

14.
This paper models competition for freight transport between the road and maritime sectors. Operators offer differentiated services and there are economies of scale in the oligopolistic shipping line sector. Two types of integration between shipping lines are considered: in one of them the liners production processes remain separate (like in an alliance); in another economies of scale are further exploited. Typically maritime freight post-merger goes down. However, it may increase if the merger exploits further economies of scale, they are important and transport services are sufficiently differentiated. An empirical application to the routes Valencia–Antwerp and Valencia–Genoa is undertaken to confirm the predictions of the model. It is shown that, for both types of merger, user surplus increases when transport services are weakly differentiated and economies of scale are sufficiently small. These conditions also guarantee that a merger is socially beneficial.  相似文献   

15.
The paper presents a dynamic model of modal split in a multimodal freight transport system, which supposes that the evolution over time of transport demand is accompanied by a corresponding evolution of transport modes, and that users react with delay to cost variations. Starting with these hypotheses, and following the paradigm of random utility, a recursive equation is obtained, whose iterated application furnishes the sequence of the demand fractions on the various transport modes in the successive epochs of the time period during which the evolution of the transport system is studied and enables forecasting the future modal split evolution.  相似文献   

16.
This paper presents direct and cross-elasticity estimates of the demands for three freight transportation modes: rail, road and inland waterways. They are computed for 10 different categories of goods with a detailed multimodal network model of Belgian freight transports. The model, which minimises the generalised cost of transportation tasks defined by O-D matrices, assigns traffic flows to the different modes, transport means and routes. Successive simulations with different relative costs permit the computation of specific arc-elasticities. In contrast with the usual methodologies, the present methodology is not based on a statistical analysis of disaggregate data on actual modal choices and transport tariffs. This is a particularly useful feature since such data are mostly not available for freight transports in Europe. Furthermore, it fully takes into account the detailed characteristics of the network, all available routes and combinations of modes, as well as the specific localisation of activities within the network. Its estimates are compared with previously published estimates, and, in particular, with Abdelwahab's results published (1998) in this journal.  相似文献   

17.
Recent research in transport appraisal has been predominantly performed by using quantitative linear additive methods such as AHP and MAUT. This paper presents a qualitative model for road investment appraisal based on the DEX method. Qualitative modelling and ability to handle inaccurate and/or incomplete data about options make the DEX method particularly well suited for decision problems involving qualitative concepts and a great deal of expert judgement as is the case in the field of transport. Introduced is a novel and practical way of road appraisal based on the road appraisal framework aimed to support transport policy development in Slovenia.  相似文献   

18.
云南铁路货运量增长问题研究   总被引:1,自引:0,他引:1  
在分析国内外铁路货运需求增长模型的基础上,提出铁路货运需求增长过程的4阶段划分理论,结合云南铁路发展滞后的现状,建立了消除铁路货运能力限制的货运量增长模型。通过对云南铁路货运量和货运需求量的计算,应用MATLAB仿真技术验证了模型的正确性,并对云南铁路货运量和货运需求量进行了预测。  相似文献   

19.
The paper applies the choice model incorporating attribute cut-offs proposed by [Swait, J.D., 2001. A non-compensatory choice model incorporating attribute cutoffs. Transportation Research: Part B 35 (10), 903–928] to evaluate shippers’ preferences for freight service attributes. A stated preference experiment on a sample of Italian manufacturing firms shows that the marginal utilities of attributes are not constant over the whole range of values presented, and that significant improvements can be made by introducing non-linearities at points specified by individual respondents. It is found that the conventional model overestimates the importance of the attributes, though their relative ranking is maintained. The proposed choice model provides useful information on the difficulty of achieving a modal transfer of freight from road to truck-rail intermodal transport.  相似文献   

20.
Freight demand elasticity studies vary significantly in terms of the demand measure, data type, estimation method, commodity type, etc. This wide variation makes it difficult to compare empirical estimates when the differences may arise in part from the methods and data used. In this paper we conduct a comparative analysis to identify systematic sources of influence on direct price elasticity estimates in the context of freight transport, distinguishing between road, rail, and sea transport, using published direct price elasticities from 12 elasticity-derivative studies from five countries. The study focuses on revealed preference elasticities defined by the freight rate for tonnes and tonne kilometres of inter-city freight movements. Systematic sources that explain differences in direct price elasticities include the demand elasticity measure, mode, commodity class, model estimation form, country, and temporal nature of data (e.g., cross-section). Analysts can utilise the model outputs to adjust the empirical evidence from specific studies to control for differences that impact on the behavioural implications of comparative evidence.  相似文献   

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