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1.
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   

2.
构建铁路快捷货运网络,提高铁路市场竞争力,对提高铁路运输经济效益和社会效益具有重要意义.综合考虑城市规模、快捷货物运输需求、对外通道连接情况等多种影响因素,提出构建由铁路快捷货运枢纽中心、快捷货运集散中心和快捷货运集散点组成的分层次城市节点网络;结合铁路网中长期规划和建设情况,探讨构建覆盖快捷货运城市节点的分层次铁路快捷货运通道网络布局方案.  相似文献   

3.
We propose a multi-depot location-routing model considering network failure, multiple uses of vehicles, and standard relief time. The model determines the locations of local depots and routing for last mile distribution after an earthquake. The model is extended to a two-stage stochastic program with random travel time to ascertain the locations of distribution centers. Small instances have been solved to optimality in GAMS. A variable neighborhood search algorithm is devised to solve the deterministic model. Computational results of our case study show that the unsatisfied demands can be significantly reduced at the cost of higher number of local depots and vehicles.  相似文献   

4.
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   

5.
印度铁路考察报告   总被引:1,自引:0,他引:1  
印度经验表明,在铁路运输资源相对落后的情况下,通过优化铁路运输组织,减少编组站作业量,开行点到点的区间列车,构建适宜的货运信息系统,压缩机车车辆周转时间,可以有效改善铁路运营效率。通过固定和可移动运输资源的共用,印度铁路承担了孟买、清奈、加尔各答、新德里等城市的市郊铁路运输。印度铁路构建"货车池"制度、减少铁路分局数量、较灵活的价格体系、货运专线规划等,对我国铁路都有一定的借鉴意义。  相似文献   

6.
Due to the increasing commercial activities in China, the rapid growth of energy consumption and greenhouse gas (GHG) emissions in the freight transport sector has alarmed the Chinese central government. However, there is a lack of standard measure for evaluating GHG emissions generated from freight transport operations. To improve this situation, Chinese policy makers need to evaluate GHG emissions for energy saving and pollution reduction. This background leads us to examine the GHG emission trajectories and features of Chinese freight transport patterns in the last decade, i.e. between 2000 and 2011. In this study, we examine different regions’ freight turnover and energy consumption by various transport modes (i.e. railway, highway, waterway, aircraft, and oil pipeline) in China. Our results show that the total amount of GHG emissions caused by the Chinese freight transport sector reached 978 million tons in 2011, indicating an average annual growth of 74 million tons CO2e for the last decade. Shandong, Anhui, and Henan are the main provinces producing GHG emissions, representing 11.7%, 10.3%, and 10% of total emissions generated from the freight transport sector in China, respectively. This study also compares the regional GHG emissions from different freight transport modes including railway, highway, waterway, air transport, and oil pipeline. Based on the findings, policy implications are provided on how to mitigate freight transport emissions among different Chinese regions.  相似文献   

7.
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   

8.
为推进南通市交通运输转型发展,优化交通基础设施空间一体布局,在经济增长中发挥好支撑引领作用,在阐述南通市综合交通枢纽布局现状、发展定位和存在问题的基础上,从强化对外综合运输通道建设、畅通周边城市城际交通网络、提升市域集散网覆盖通达水平、大力发展多式联运系统和促进综合货运枢纽高效衔接5个方面提出南通市综合交通枢纽布局优化对策。综合交通枢纽的布局优化,有利于完善南通市的枢纽功能,进一步提升其在全国综合交通体系中的战略地位,发展枢纽经济,实现经济转型,加快打造成长三角北冀经济中心。  相似文献   

9.
Goods movement and freight distribution are widely underrepresented in regional science and geographical research. This is surprising since a large body of traditional spatial theory has been developed with respect to transportation costs or to trade areas: those aspects that were originally closely connected with the exchange of goods. Growing attention is being paid in geography to related subjects, such as the emergence of global production networks, to structural changes in retail or to the commodification of modern consumption. To a certain extent, these processes depend upon the efficient transfer of information, finance and physical goods. Yet, with a few exceptions, the freight sector appears to be neglected in contemporary research. This paper provides an overview of the emerging transport geography of logistics and freight distribution. It challenges the traditional perspective where transportation is considered as a derived demand with the idea that logistical requirements underline transportation as a component of an integrated demand. The paper provides an analysis of the evolution of logistics as it pertains to the core dimensions of transport geography (flows, nodes/locations and networks). The concept of logistical friction is also introduced to illustrate the inclusion of the multidimensional notion of impedance in integrated freight transport demand.  相似文献   

10.
2021年,全路货运系统深入推进运输结构调整,大力实施以货补客,深化货运组织改革,高站位完成重点物资保供任务,高质量完成多式联运发展目标,货运服务质量和信息化水平进一步提升,货运安全管理进一步强化,货运安全局面持续稳定。2022年,全路货运系统要抢抓机遇、担当作为,深入开展货运安全专项整治、强化货运专业管理基础、扩大“公转铁”工作成效、加快集装箱多式联运发展、促进专业物流稳步增量、服务“一带一路”建设,在全面深化基础管理、持续推进运输结构调整、优化“一带一路”铁路运输组织、持续深化货运组织改革、强化队伍建设和监督检查上取得新成效,奋力推动铁路货运高质量发展。  相似文献   

11.
The research germinates from the statement that the cities have to solve the impacts due to freight transport in order to improve their sustainability implementing sets of city logistics measures. But city logistics measures involve several actors and choice dimensions. It is therefore important to have methods and models able to assess the effectiveness of the measures to be implemented. The current models were mainly developed to simulate some aspects of urban freight transport, and are not able to forecast many impacts of implementing traffic and transportation measures at an urban scale.This paper presents a modelling approach that tries to point out the relations existing among city logistics measures, actors and choice dimensions. It comprises three model sub-systems to estimate the quantity O–D matrices by transport service type (e.g. retailer on own account or wholesaler on own account or by carrier), the delivery O–D matrices by delivery time period, and the vehicle O–D matrices according to delivery tour departure time and vehicle type.This modelling system is a multi-stage model and considers a discrete choice approach for each decisional level. It was first tested using some data collected in the inner area of Rome, including traffic counts and interviews with retailers and truck-drivers. The model estimations were also compared with the experimental ones, and quite satisfactory results were obtained.  相似文献   

12.
Goods distribution is a growing proportion of intra-urban transport worldwide due to changes in supply chains and e-commerce, yet has received scant attention in research. Cities have opted for a regulatory approach to truck movement and deliveries at a local level but few have tried to develop a systematic approach to management. Following certain suggestions in the literature, a hierarchical deliveries approach is being adopted in some new developments in Europe and Australia using light vehicles at the local level. In East, South and South-East Asia, where 3-wheeled non-motorised vehicles have been a mainstay of goods and people transport for several decades, they are under renewed pressure from city governments. This study of the tricycle in Beijing examines their role for packages delivery, food and beverage distribution and waste and recycling services, which covers nearly all of the uses of utilitarian tricycles in northern Chinese cities. Drivers (n = 97) were interviewed, their usual trips were mapped, and the subsequent trip was recorded using a geo-positioning system. These trips were compared with trips executed by small, motorised vans, favoured since 2014 by Beijing government. Operations can be divided into four categories according to delivery chain organisation, field operations and vehicle type. Motorised alternatives to the tricycle are shown to be uncompetitive in terms of time, cost and energy efficiency. This first detailed examination of the operations of the tricycle in a Chinese city provides a useful base for consideration of local distribution services organisation and a possible model for cities outside China.  相似文献   

13.
This paper presents a discrete network design problem for optimally designing freight transport network in terms of the efficiency of supply chain. Modelling is undertaken within the framework of mathematical programmes with equilibrium constraints, which first incorporates both supply chain and transport networks explicitly. The upper level determines the best set of actions for transport network improvement, while the lower-level decision is based on a supply chain–multimodal transport supernetwork equilibrium. New variants of particle swarm optimisation are developed to approximately solve the upper level. Numerical tests reveal their superior performance and the effective freight transport-related actions.  相似文献   

14.
This paper presents a three-stage mixed-integer stochastic programming model for disaster response planning, considering the opening of local distribution facilities, initial allocation of supplies, and last mile distribution of aid. The vehicles available for transportation, the state of the infrastructure and the demand of the potential beneficiaries are considered as stochastic elements. Extensive computational testing performed on realistic instances shows that the solutions produced by the stochastic programming model are significantly better than those produced by a deterministic expected value approach.  相似文献   

15.
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   

16.
Over the last +35 years at least five concepts – multimodal, intermodal, combined, co-modal and synchromodal – relating to freight transport chains have been put forward. I pinpoint the main properties of each concept and trace a plausible evolutionary path. The original concept is multimodal transport; the newest one is synchromodal transport. Every new concept borrows certain elements from the previous concepts and introduces new ones.This profusion of concepts is not in itself a hindrance. However, the concepts do exhibit substantial areas of overlap and ambiguity. This status quo facilitates misinterpretation of research efforts and hampers the coherent development of theory, regulations and policies.In this viewpoint, I argue that such an orderly situation can only be attained if there is a unified, or at least consensual, ontology. With an ontology in place, we would (re-)specify the existent concepts following the same principles. The outcome would be unambiguous meanings and clear limits. And herein lies, in my view, the main limitation we face: we still have to agree on the respective domains of specification and on the nature of each concept.I identify a total of four domains, which are: technological domain, organisational and managerial domains, production domain and externalities domain.  相似文献   

17.
Adoption of electric vehicles by transport companies remains limited although major European cities should reach CO2-free city logistics by 2030. This paper explores therefore the vehicle choice behaviour of transport companies through a conjoint-based choice analysis.The results showed that the benefits of battery electric vehicles are less valued than their disadvantages. However, a majority of respondents agrees that authorities should encourage the use of battery electric vehicles. Based on the preferences of transporters, we conclude that the most important measures are to develop a larger charging infrastructure and implement financial incentives through subsidies or tax exemption.  相似文献   

18.
《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   

19.
With two of the busiest air traffic corridors globally, Sydney-Melbourne (SYD-MEL) and Sydney-Brisbane (SYD-BNE), very liberal open skies agreements, and the world's most isolated large city in Perth, air freight in Australia should be destined for substantial growth, but has in contrast to other regions such as the US not yet materialised. This paper identifies challenges surrounding domestic air freight markets in Australia and compares the provision of road vs air freight services utilising gravity modelling methods. Our findings suggest the impedance of domestic air freight services in Australia is greater for regional areas between the primary cities (such as Canberra, between Sydney and Melbourne) than remoter areas (such as Cairns in Northern Australia). Our models show further that in addition to distance, air freight capacity on any of our analysed routes is despite being demand-pulled in terms of GDP dependency significantly attuned to factors at both the origin (in particular domestic trade capability, i.e. manufacturing and logistics) and destination.  相似文献   

20.
This paper presents a freight transport optimization model that simultaneously incorporates multimodal infrastructure, hub-based service network structures, and the various design objectives of multiple actors. The model has been calibrated and validated using real-life data from the case study of hinterland container transport of the Netherlands, where CO2 pricing, terminal network configuration, and hub-service networks are chosen as the design measures. Policy packages combining multiple types of policies show better network performance as compared with the optimal performance resulting from a single policy type. This illustrates the value of incorporating multiple types of policies simultaneously in freight transport optimization.  相似文献   

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