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1.
This paper develops a model that enables comparative analysis of intermodal and synchromodal operations from economic, societal, and environmental perspectives. The model captures relevant (day-to-day and within-day) dynamics in freight transport demand and supply, flexible multimodal routing with transfers and transhipments. The capacitated schedule-based assignment algorithm operating specifically at path level allows strategic modelling and evaluation accounting for the freight transport system at operational level. The Rotterdam hinterland container transport case study shows that synchromodal system is likely to improve transport service level, capacity utilization, and modal shift, but not to reduce delivery costs.  相似文献   

2.
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   

3.
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   

4.
This paper presents an agent-based approach to commodity transport modeling. It assesses the effects of behavior-oriented transport policy measures while taking complex logistics reaction patterns into account. It is structured by modules describing company generation, supplier choice, shipment-size choice, carrier choice and tour construction. The behavior of individual actors is simulated using normative logistics models and accumulated market knowledge. Using a bottom-up approach, shippers and carriers interact through simulated auctions of transport contracts resulting in the generation of tours. Simulations using the model prototype INTERLOG calibrated with German data demonstrate the capabilities and limitations of this approach.  相似文献   

5.
Despite their potential, cargo airships currently remain a theoretical concept. This research aims to examine the factors determining the demand for their services from the perspective of transport logistics professionals. An online freight mode choice experiment is conducted, supplemented with follow-up semi-structured interviews. Across freight types the sensitivity of the modes (road, rail, sea and airship) to the attributes (price, time, reliability and frequency) varied substantially. Willingness to pay for the cargo airship mode for travel time saved is estimated to be $23/tonne/hour. It is conservatively estimated that the potential market share of cargo airships in the Australian domestic freight market varies across airship models with LMH-1 having the lowest market share of 8% while ARH50 has the largest potential market share at 25%.  相似文献   

6.
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   

7.
A proposal for evaluating the attractiveness of the first European ro–ro service based on traditional bogies is presented, to estimate to what extent its realization is able to influence distribution of freight transport, between the traditional road transport and the new alternative available, through the specification and calibration of a modal split model (Logit), based on random utility theory. For the scenarios analyzed, the model estimates that nearly 4% of the total shipments would use the ro–ro service, when its frequency is four journeys per day, and about 9%, in the case of increased frequency to ten.  相似文献   

8.
分析中国铁路货运的发展形势,建立关于铁路、公路货运量在全社会货运量中所占市场份额的差分方程组模型,运算后得出铁路货运在整个货运市场中的占有率趋向。通过利用历史统计数据计算,得到铁路货运市场占有率的一个数值解。  相似文献   

9.
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   

10.
This research addresses strategic planning for an interregional, hub based, intermodal logistics network operated by a logistics service provider. A tabu search meta-heuristic is used to solve a mathematical optimization model that extends the p-hub median model for interacting hub location-allocation problems to the domain of intermodal logistics. An empirical study based on a subset of US freight flows shows that intermodal logistics networks differ significantly from traditional over-the-road logistics networks in their hub locations, network structure, and their use of direct and inter-hub shipments. Furthermore, intermodal logistics networks are more sensitive to changes in service requirements and costs.  相似文献   

11.
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   

12.
Optimizing the aerodynamic efficiency of intermodal freight trains   总被引:1,自引:0,他引:1  
We develop an aerodynamic loading assignment model for intermodal freight trains based on an integer-programming framework to help terminal managers make up more fuel-efficient trains. This is the first use of optimization modeling to address the aerodynamics and energy efficiency of railroad intermodal trains. Several recommendations regarding railway equipment use, operations, and policy are proposed to improve fuel-efficiency and reduce emissions from intermodal transportation. Analysis of one major railroad intermodal route reveals the potential to reduce fuel consumption by 15 million gallons per year with corresponding savings of $28,000,000. Greater benefits are possible through broader implementation of the model.  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.
This paper explores the possibility of implementing innovative bundling models and new-generation terminals as a means to integrate small flows, mainly from outside the economic core areas, in the intermodal transport system. Any integration of these small flows would increase the transport volume that is potentially suitable for intermodal transportation, and could therefore add to the modal shift from road to rail. To illustrate this concept, it will be applied to the proposed terminal in Valburg in the Netherlands. The theoretical and practical results of this example will be discussed in the context of the more general research on innovative intermodal transport.  相似文献   

15.
The paper deals with a quantitative analysis on the competitiveness of intermodal transport, based on Motorways of the Sea (MoS), in comparison with all-road transport. This analysis is applied to MoS routes connecting the Italian mainland with Sicily. The study involves: a detailed intermodal network model which compares monetary costs and travel times from all relevant origins in the mainland to all relevant destinations in Sicily; and a survey carried out at some representative trucking firms operating to/from Sicily. The aim of the interviews has been: on one side to make a comparison between the theoretical and actual mode of transport and routes taken, and in case they are different, to understand the reasons of the discrepancy; on the other side to determine what are the main aspects taken into account by trucking companies in their modal choice, in order to understand how the competiveness of MoS against road transport can be improved. The results of the analysis show that the modal choice is affected by several elements: monetary costs and travel times; reliability of MoS routes; availability of MoS routes; MoS routes frequencies; but it resulted from the interviews that monetary costs and travel times are the most important factors considered by trucking companies in the modal and route choice. This study has also shown that an improvement of MoS routes on the Italian Adriatic side is necessary: actually, a strong reason for which in Italy MoS traffic is still a small percentage of road traffic is the low number of MoS routes currently in operation and their low frequency. This analysis could help decision makers, and maritime operators, to efficiently invest in the improvement of MoS routes. Moreover, this analysis, developed for an Italian case study, can be applied to other European and Mediterranean scenarios.  相似文献   

16.
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   

17.
This paper obtains the optimal routings for intermodal containerized transport from Canada to Mexico. Such traffic is being stimulated by the North American Free Trade Agreement (NAFTA), but the cost and lead times of feasible routes are not well known. We summarize the links and routes to Mexico on which one or more carriers now operate, and then determine non-dominated tradeoffs between cost and service. Every southbound route from Canada requires a transshipment point in the southern or southwestern U. S. Feasible transshipment points are also candidate locations for a manufacturing ‘twin plant’, a distribution centre, or a transportation hub. Here, as a first step in this bigger problem, a network is constructed between five Canadian origins and three important Mexican destinations. Each link employs available intermodal services whose transit time and transportation cost are obtained through industry sources. A shortest-path algorithm enables calculation of the route requiring least time and the route of minimum cost. Non-dominated time/cost tradeoffs are identified for each origin–destination pair. After including inventory expenses (by parametrizing the unit value of lead time), total-cost curves then eliminate some routing alternatives. Guidelines are provided on the effects of mode, carrier, and O–D locations on selection of intermodal routes to Mexico. Finally, two new intermodal services are proposed and their benefits discussed.  相似文献   

18.
This paper presents an intermodal network optimization model to examine the competitiveness of 36 alternative routings for freight moving from China to and beyond Indian Ocean. The proposed model, which is built upon the principles of goal programming, is able to handle multiple and conflicting objective functions such as minimizing transportation cost, transit time and transit time variability while ensuring flow continuity and transit nodes compatibility among the rail, road, ocean vessel, airplane and inland waterway transports. Transportation time and cost obtained from comprehensive industry sources are then fed into the intermodal transport network connecting two important Chinese origins and four Indian destinations, from which the most attractive routes are identified. In addition, the paper investigates several non-dominated transportation cases through sensitivity analysis tests, and analyzes the potential competitiveness and possible influences of future route developments to current transportation patterns in Asia.  相似文献   

19.
铁路运输企业要想在激烈的运输市场竞争中继续发挥好骨干作用,就必须用高质量的服务赢得客户、赢得市场。对铁路货运改革的主要举措即敞开收货、实货制运输、一口价收费、门到门运输进行了分析,从铁路服务理念、服务项目、服务评价、服务监管四个方面剖析当前铁路服务质量与新形势、新要求的差距。提出了铁路服务质量提高的几点建议,包括树立以人为本的服务理念,创新服务手段和服务项目,加强服务管理,健全服务监督体系,完善服务质量评价体系。  相似文献   

20.
The post-war era saw a dramatic decline in both the volume and market share of freight transported by rail in Britain. This decline was associated with the closure of thousands of rail freight facilities and reduction by one third in the route mileage of the national railway network. However, as a result of railway privatisation and increasing constraints on the competitiveness of the road haulage industry, the long decline has halted and rail freight traffic is growing. This article reviews the implications of this change for the demand for rail freight facilities and for extra capacity in the railway network, and considers how the land-use planning and transport planning systems might respond.  相似文献   

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