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1.
《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   

2.
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   

3.
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   

4.
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   

5.
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   

6.
This paper presents one of the first models explaining the choice of time-period in road freight transport. Policies that would shift some fraction of the trucks from peak to earlier and later periods will contribute to the reduction of congestion. Therefore there is an increasing interest in modelling the time-period sensitivity of road freight transport to changes in travel time and cost by period. The model developed here is based on a stated preference survey amongst receivers of goods in Flanders and was implemented in the strategic freight transport model of the Flemish authorities.  相似文献   

7.
Urban population growth and economic development have led to the creation of new communities, jobs and services at places where the existing road network might not cover or efficiently handle traffic. This generates isolated pockets of areas which are difficult to reach through the transport system. To address this accessibility problem, we have developed a novel approach to systematically examine the current urban land use and road network conditions as well as to identify poorly connected regions, using GPS data collected from taxis. This method is composed of four major steps. First, city-wide passenger travel demand patterns and travel times are modeled based on GPS trajectories. Upon this model, high density residential regions are then identified, and measures to assess accessibility of each of these places are developed. Next, the regions with the lowest level of accessibility among all the residential areas are detected, and finally the detected regions are further examined and specific transport situations are analyzed.By applying the proposed method to the Chinese city of Harbin, we have identified 20 regions that have the lowest level of accessibility by car among all the identified residential areas. A serious reachability problem to petrol stations has also been discovered, in which drivers from 92.6% of the residential areas have to travel longer than 30 min to refill their cars. Furthermore, the comparison against a baseline model reveals the capacity of the derived measures in accounting for the actual travel routes under divergent traffic conditions. The experimental results demonstrate the potential and effectiveness of the proposed method in detecting car-based accessibility problems, contributing towards the development of urban road networks into a system that has better reachability and more reduced inequity.  相似文献   

8.
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   

9.
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   

10.
《Transport Policy》2008,15(2):104-112
The ‘Network City’ planning strategy espouses sustainable accessibility. The aim is to re-orient the existing urban structure by focussing development at places with high accessibility in order to support an effective public and private transport system. The implementation phase calls for changes to planning practices: the need for public transport planning and development change to be mutually supportive; the need for road network planning and road design to place land use-transport integration as the core objective rather than traffic efficiency and for the need to stage development according to planned population and employment targets. This must take place within a new participatory approach. All this requires planners to gain new skills. To achieve this the system of planning must remain strong.  相似文献   

11.
Longer and more frequent traffic jams in the Netherlands are increasing the costs of transporting cargo. Tightly scheduled production systems rely on punctual materials movements, but are congestion-induced delays sufficient to stimulate freight mode switching from road to combined road–rail and road–water movements? A survey of Dutch transport companies revealed an estimated 10% of vehicle operating time spent in congested conditions. The perceived impact on transport operations, consumers and service characteristics are reported. Based on the survey findings, a vehicle cost simulation attributed 7% of transport costs to congestion, increasing the attractiveness of multimodal transport and other solutions.  相似文献   

12.
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   

13.
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   

14.
A bi-level modelling approach is proposed to represent the interaction between the vehicle loading practices of road freight transport carriers, and the decisions of a road planning authority responsible both for road maintenance and for the enforcement of overloading control. At the lower (reactive) level, the overloading decisions of the carriers impact on road maintenance expenditure, while at the upper (anticipatory) level the planner decides fine and enforcement levels by anticipating the responses of the carriers. A case study using data from Mexico is used to illustrate the method.  相似文献   

15.
Lack of cross-border transport supply has repeatedly been blamed for the fact that national borders limit spatial interaction and, consequently, the growth of border regions. This study applies an accessibility approach to investigate for most municipalities in ten countries in mainland West Europe if foreign transport supply is lagging behind, and if population growth in these municipalities has been affected by the limits that national borders have imposed on market access. To do so, data describing historical population changes and road networks between 1961 and 2011 have been used. The results show that in the study area, cross-border transport accessibility was not at a disadvantage in 1961 and has since then grown even more than domestic accessibility. However, municipal population growth has depended almost exclusively on domestic market access. Processes of economic international integration in the study area are found to coincide with the growth of cross-border accessibility, but do not have a clear coincidence with the effects of cross-border accessibility on population growth.  相似文献   

16.
This paper deals with the problem of optimally locating rail/road terminals for freight transport. A linear 0-1 program is formulated and solved by a heuristic approach. The model is applied to the rail/road transportation system in the Iberian Peninsula. Five planning scenarios are considered. It is shown that modal shares are very sensitive to the cost of rail and to that of track gauge changes at the Spanish border. Conversely, the location of the terminals has little or no impact on the market shares of the combined traffic, but location changes in the Peninsula generate consequences on the entire European transportation system.  相似文献   

17.
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   

18.
In order to improve the competitive position and efficiency level of multimodal transport, consolidation of freight flows is often suggested. Bundling networks require cooperation between multiple partners in the multimodal transport chain. In this context, the question rises how benefits may be allocated fairly among the spatially distributed participants in the cooperation. A great deal of scientific literature reports on the behavior of allocation methods in collaborations between shippers or carriers making use of unimodal road transport. However, research on cost or savings allocation methods in multimodal transport is scarce. The main contribution of this paper is thus to provide a first insight in the complexity of sharing cost savings fairly among shippers who bundle freight flows in order to reach economies of scale in multimodal barge transport. By applying four different allocation methods to two realistic case studies, a comparison is made between simple and straightforward allocation mechanisms and more advanced techniques based on cooperative game theory. Special attention is paid to the savings division among coalition partners and collaborative stability. Results demonstrate the influence of cooperation characteristics on allocation outcomes and underline the value of carefully selecting appropriate allocation mechanisms when long-term stability of the multimodal barge collaboration is aspired.  相似文献   

19.
Urban rail systems have been added to public transport systems, thereby changing distribution disparities in urban spatial accessibility. These disparities reflect both the ability of the public transport system to meet the needs of residents and the locational pros and cons of public service facilities. In this paper, integrated accessibility metrics are used to assess the disparities in Nanjing, Jiangsu Province, China. This is achieved by dividing the urban space into a multilevel grid that can be easily combined with grid-based population data to facilitate accessibility modeling, calculation, and evaluation. Additionally, an acquisition method for more accurate travel time data in the multimodal public transportation network was developed on the basis of an Internet mapping service. This provides a realistic, multimodal, door-to-door modeling approach that avoids the requirement of building complex traffic networks through Geographic Information System (GIS) software and simplifies road network modeling efforts. The results show that this modeling method can be used to reflect the accessibility disparities in the Nanjing urban space objectively and accurately.  相似文献   

20.
This paper develops earlier conceptual frameworks and methods for analyzing the indirect development effects of improved road accessibility. The creation of economic opportunity and response to economic opportunity are the two concepts used in the theoretical framework, while time-series data, a road accessibility inventory, and a multi-criteria analysis were the methods used to analyse the indirect effects among households and household firms. A weakness of many impact studies is that they merely chart aggregate economic development. The method employed here includes access to resources by various groups and therefore enables the focus to shift from mere aggregate economic development to also encompass equitable and sustainable social development. The study focused on a rural Philippine fishing community, previously characterized by poor transport conditions and poor accessibility to major markets. It found that the benefits of the road improvement were considerable and benefited a great majority of the population in the fishing community. In addition to the extensive direct effects of the improved road, a number of complementary factors led to substantial indirect effects. These included: abundance of harvested resource in the community; a potential for technical innovations that increased production and productivity; available investment to support this increased production; abundant demand for this increased production in the market region (the market widened in spatial terms and prices were maintained).  相似文献   

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