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1.
Port carbon dioxide (CO2) emissions in China have become an ever-increasing public concern due to their significant impacts on human health and the environment. However, existing studies focus mainly on CO2 emissions from vessels calling at the ports and cargo handling within the ports, paying little attention to the inland distribution networks. To fill this gap, this paper proposes an easily implemented method for calculating CO2 emissions from port container distribution (PCD) and investigates their spatial characteristics and driving factors. By analyzing 30 container ports in China, the main findings are as follows. First, road transportation is the major contributor of CO2 emissions from PCD due to the lack of rail and inland water transportation. Second, PCD carbon emissions exhibit significant local spatial clustering. That is, ports with similar geographical locations tend to present a similar pattern of PCD carbon emissions. Third, as suggested by the spatial Durbin model, PCD carbon emissions are negatively determined by local gross domestic product, number of port berths, but are positively determined by local tertiary industry value and highway freight volume, and waterway freight volume in both local and neighboring ports. These results provide empirical insights into cross-port collaboration in reducing PCD carbon emissions.  相似文献   

2.
This paper unveils the competitive dynamics between the major container ports in East Asia by analyzing their extent and intensity. Time series data, with the longest series dating back to 1970 ending 2001, on container throughput for the ports of Hong Kong, Kaohsiung, Keelung, Kobe, Nagoya, Osaka, Pusan, Taichung, Tokyo and Yokohama are computed. Cointegration tests are employed to determine the existence of long run relationship between various port pairs. Error correction models are constructed to determine short run inter-port dynamics. The results reveal that Hong Kong and Pusan are beneficiaries from inter-port competition in the region for the past three decades. The study suggests that inter-port competition in the region would intensify in the future as the centre of gravity of cargo volume shifts to mainland China. Moreover, concentration of services by shipping lines at the primary load centers might lead to intense competition between the primary load centers and ports located in close proximity that share their hinterlands.  相似文献   

3.
This paper addresses a hub-and-spoke network problem for railroad freight, where a central planner is to find transport routes, frequency of service, length of trains to be used, and transportation volume. Hub-and-spoke networks, often found in air freight, have not been favoured by railways in the past. Such a structure could be profitable, however, if there exist concentrated freight flows on some service links. We formulate a linear integer programming model whose objective function includes not only the typical operational cost, but also cost due to the transit time spent by freight in the network. We then develop heuristic algorithms to solve large scale instances occurring in rail freight systems in France plus Italy; Germany; and a 10-country European network. By assuming that every node is equipped with consolidation capability, we let the final solution naturally reveal potential hub locations, the impact of several of which is studied by sensitivity analysis.  相似文献   

4.
Efficient maritime transportation is heavily dependent on the smooth operation of land transportation. Swift modal transfers are key to successful intermodal operations. In this paper we examine the efficiency of maritime intermodal transfer facilities in California, from the point of view of the trucking companies that use these facilities. We also examine the perceived effects of traffic network congestion on intermodal carriers' operations. Conclusions are based on a recent survey of nearly 1200 private and for-hire carriers operating in California. Over 450 of the companies surveyed had operations involving maritime ports in California. These provided a rich sample of responses and significant insights into the current state of the industry.  相似文献   

5.
Abstract

In comparison to personal travel, freight movements within large metropolitan areas are much less studied. Most conventional transportation models and planning analysis that disregarded freight flows have been criticized on the plausibility of their results and conclusions. To alleviate these problems, this study proposes a non-survey based approach to assemble and process freight data in a systematic way. A freight origin–destination (OD) matrix of freight flows can be developed using secondary data sources. The estimated freight flows can be loaded together with conventional passenger flows onto the regional highway network of a large metropolitan area. As a case study, this non-survey based approach was applied to build a freight OD and study the traffic flows in Los Angeles. It concluded that this approach can be used to analyze urban freight movement in a low-cost way in which planning agencies can overcome the common omission of freight flow information in their transportation plans.  相似文献   

6.
This paper investigates intermodal freight transport planning problems among deep-sea terminals and inland terminals in hinterland haulage for a horizontally fully integrated intermodal freight transport operator at the tactical container flow level. An intermodal freight transport network (IFTN) model is first developed to capture the key characteristics of intermodal freight transport such as the modality change phenomena at intermodal terminals, physical capacity constraints of the network, time-dependent transport times on freeways, and time schedules for trains and barges. After that, the intermodal freight transport planning problem is formulated as an optimal intermodal container flow control problem from a system and control perspective with the use of the proposed IFTN model. To deal with the dynamic transport demands and dynamic traffic conditions in the IFTN, a receding horizon intermodal container flow control (RIFC) approach is proposed to control and to reassign intermodal container flows in a receding horizon way. This container flow control approach involves solving linear programming problems and is suited for transport planning on large-sized networks. Both an all-or-nothing approach and the proposed RIFC approach are evaluated through simulation studies. Simulation results show the potential of the proposed RIFC approach.  相似文献   

7.
This paper proposes the conceptual model of the Asian (Port) Doctrine to explain the successful development of top ranking container ports in Asia during the past four decades. This paper draws a new paradigm for the role of government as a third governance approach in addition to Anglo-Saxon and European doctrines by describing how Asian countries have developed container hub ports by investing in infrastructure as social overhead capital to support export-led growth. We survey characteristics and outcomes in major Asian container port developments and one European port in terms of a port development policy. The findings are presented in a comparative overview of government investment in functional elements of port, maritime infrastructure and landside connections to container ports. This paper confirms that the existing two doctrines—Anglo-Saxon and European doctrines—are not sufficient to explain the Asian success in major container port developments. The proposed framework contends that a newly proposed Asian Doctrine can accomplish this with the help of cross-subsidization, strategic and administered port pricing mechanism.  相似文献   

8.
There are many studies on container port efficiency and that seek to understand what factors, such as technical and scale efficiency, private versus public terminal management or macro-economic factors, play on the efficiency score of a given port. There are fewer studies that focus on the role played by the inter-port competitive environment. This role remains difficult to assess. In fact, on the one hand, a port subject to high inter-port competition may record higher efficiency scores due to the pressure from the competitive environment. On the other hand, a port subject to high competition may be forced to over-invest and could therefore records a lower efficiency score. This article investigates this issue and examines how the degree of competition measured at different levels (local, regional and global level) impacts the efficiency score of a given container port. To do so, we implement a truncated regression with a parametric bootstrapping model. The model applied to information gathered for 200 container ports in 2007 and 2010 leads to the following conclusions: port efficiency decreases with competition intensity when measured in a range of 400–800 km (regional level); and the effect from competition is not significant when competition is measured at a local (less than 300 km) or at a global (more than 800 km) level. Estimates also show a tendency for ports who invested from 2007 to 2010 to experience a general decrease in efficiency scores, an element which could be explained by the time lag between the investment and the subsequent potential increase in container throughput.  相似文献   

9.
Understanding the relationship between socioeconomic factors and the Less-than-Truckload (LTL) freight flows is important for transportation planners and policy makers. This paper explores the impacts of information technology, urbanization on LTL freight flows by using a spatial autocorrelation model with freight flow data from a leading LTL company in China. The results show that all IT variables and urbanization variables have positive effects on freight flows. Distance, as expected, is negatively correlated with the freight flow volume. The application of the spatial autocorrelation model further shows that origin dependence, destination dependence and OD dependence are all significant, justifying the consideration of spatial interdependence. Finally, policy implications are discussed based on the estimated results. These findings shed light on the impacts of internet and urbanization on freight transportation, and contribute to the design of freight policies and the development of the LTL industry.  相似文献   

10.
This paper presents an approach to making long-term forecasts of overseas container traffic in the port of Montreal. The paper discusses, first, why performance models explaining traffic variations in ports when postulating a fixed hinterland may not be appropriate for the port of Montreal. Then, the forecasting approach itself is presented. Using 1981 as the base year, projections of container traffic through the port of Montreal until 1995 are developed by considering separately the traffic flows associated with the Canadian and the United States hinterlands. Our approach takes account of anticipated changes in Canadian and U.S. international trade volume, containerization rates and regional growth within Canada. It yields detailed forecasts of containerized traffic, by origin and destination, for 78 commodity groups, 7 world regions and 11 North American regions (i.e. the 10 Canadian provinces plus the United States). Two forecasting scenarios are considered and the aggregate results for 1995 are reported. Finally, a comparison of forecasts with recent data available for 1984 is made, suggesting that the internation trade projections used to generate our forecasts may be too conservative.  相似文献   

11.
Using a game theory approach, this paper analyses a situation in which the government imposes a certain emission tax on vessels and port operations for emission control in port areas. Two ports are considered: a purely private port and a landlord (partial public) port. These two ports are in Cournot or Bertrand competition or cooperation with differentiated service. Our model outcomes lead to the following conclusions. First, the optimal private level of port 2 under Cournot and Bertrand competitions varies between fully private and highly public concerned port, while government will prefer a highly public concerned or close to highly public concerned port in the cooperation scenario. Second, government will have to make more and stricter efforts to enhance environmental protection in the situation of port cooperation (monopoly) than in the case of inter-port competition, and all the optimal emission tax should be always lower than the marginal emission damage. Third, port privatization has a non-monotonous effect on ports’ environmental damage in the inter-port competition scenarios and a monotonous decreasing effect in the cooperation scenario. Fourth, the total emission tax revenue is always higher than the overall environmental damage in the cooperative scenario, and it may or may not be able to cover the whole environment damage in Cournot and Bertrand competitions. Finally, the government may face a trade-off among environmental protection, maximizing social welfare, satisfying individual motivation, when considering port cooperation (monopoly).  相似文献   

12.
Abstract

The institutional environment of rail transport has changed as a result of recent European directives, but the changes have taken different forms from one country to another. In the case of international maritime chains, the development of door‐to‐door services makes inland haulage from the loading and discharging ports extremely important, and it highlights the need to reshape the rail freight industry. This paper analyses the degree of involvement of different actors drawn from the maritime industry in developing and commercializing rail services in the changing regulatory environment. Several maritime operators, shipping lines, port‐handling companies and port authorities have been involved in some container rail services since the early days of liberalization. Their commitments take very different forms, however. Whereas contracts are mainly used for the provision of service, particularly for train haulage, integration by means of shareholding or creating subsidiaries or joint ventures is used for marketing. Important differences between France, the UK, Germany and the Netherlands are detailed. In the latter two countries, there is more involvement in the provision of rail services. Marketing rail services appear to be the main strategic issue for the maritime operators in all four countries  相似文献   

13.
广西沿海铁路作为大西南的重要出海通道,是防城、钦州、北海等重要沿海港口主要的后方集疏运干线。文章提出了广西沿海铁路开行双层集装箱列车的意义,预测了广西沿海铁路集装箱的运量,从经济与通过能力方面分析了广西沿海铁路开行双层集装箱列车的必要性。  相似文献   

14.
Trucking, rail and other types of transportation networks share the common feature of moving equipment and crews between spatially separated terminals to accommodate the transportation of goods or people. This paper develops measures for temporal and spatial imbalances in freight flows, and applies these measures to a major trucking network. Fundamentally, the randomness inherent to a system of terminals is mitigated by pooling freight flows among terminal groups, and by pooling freight flows over many time periods. In the terminal network that we examined, long-run freight imbalances ensure that empty equipment movements must equal or exceed 13.3% of loaded movements at individual terminals and 8.2% of loaded movements at terminal groups. Due to short-run freight imbalances, the number of empty movements could increase by about 50% over the long-run average; greater increases would occur if equipment flows must be balanced on each travel lane. ©  相似文献   

15.
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   

16.
The current models for hub location problems are unable to find potential hub locations in uncharted areas that currently have no port. To explore hub locations that are not selected from the present ports, this study proposes a two-stage method to address this gap in knowledge. A concave cost multicommodity network flow model is solved in the first stage to obtain container traffic in waterways. Then, in the second stage, a hubbing probability is evaluated for each node to indicate potential hub locations. A case study including emerging Arctic routes is provided to demonstrate this method.  相似文献   

17.
Abstract

Despite a concentration of container traffic in the southeast of the UK over the last few decades, regional ports are attempting new development strategies to capture or retain specific traffic segments. These include intra-European short-sea traffic and a potentially increasing feeder market. These trends are reflected in the movement of different container types, which result in a number of planning challenges related to changing infrastructural and operational requirements. This paper uses highly disaggregated data on container type movements to address three issues that can inform these planning challenges. First, the imbalance of trade resulting in empty container repositioning; second, the requirement for gauge-cleared rail routes to cater for the increasing proportion of high-cube containers; and third, the specialisation of European short-sea traffic at secondary UK ports. The results reveal the disproportionate repositioning of empty containers at Scottish ports and the importance of 45?ft, high-cube and pallet-wide containers at regional ports, highlighting their focus on intra-European short-sea traffic and raising difficulties relating to their lower quality of landside infrastructure (particularly rail) in comparison to the large south-eastern ports. The potential repercussions on hinterland infrastructure development raise questions about both public and private sector responses to regional port development.  相似文献   

18.
In this paper we review the dry port concept and its outfalls in terms of optimal design and management of freight distribution. Some optimization challenges arising from the presence of dry ports in intermodal freight transport systems are presented and discussed. Then we consider the tactical planning problem of defining the optimal routes and schedules for the fleet of vehicles providing transportation services between the terminals of a dry-port-based intermodal system. An original service network design model based on a mixed integer programming mathematical formulation is proposed to solve the considered problem. An experimental framework built upon realistic instances inspired by regional cases is described and the computational results of the model are presented and discussed.  相似文献   

19.
This paper introduces a model of urban freight demand that seeks to estimate tour flows from secondary data sources e.g., traffic counts, to bypass the need for expensive surveys. The model discussed in this paper, referred as Freight Tour Synthesis (FTS), enhances current techniques by incorporating the time-dependent tour-based behavior of freight vehicles, and the decision maker’s (e.g., metropolitan planning agency planner) preferences for different sources of information. The model, based on entropy maximization theory, estimates the most likely set of tour flows, given a set of freight trip generation estimates, a set of traffic counts per time interval, and total freight transportation cost in the network. The type of inputs used allows the assessment of changes in infrastructure, policy and land use. The ability of the model to replicate actual values is assessed using the Denver Region (CO) as a case study.  相似文献   

20.
Seaport operations are highly important for industries which rely heavily on imports and exports. A reliable evaluation of port risks is essential to govern the normal running of seaborne transportation and thus the industrial economies. The occurrence of a breakdown in the trade facilitators, such as ports, will disrupt the smooth flow of supply chains for the industries. The estimation of the economic loss for an industry when a port gets disrupted is a challenging task as the relationship between the port and industry clusters is complex. This study aims to develop a systematic framework for performing economic loss estimation of industry clusters due to port disruptions. The whole risk assessment is split into three stages focusing on the establishment of a network flow model, economic estimations and evaluating risk mitigation strategies. The proposed idea is demonstrated by a case study on Shenzhen port and its related manufacturing industries. A dynamic inventory control strategy used by manufacturers is found to be beneficial for mitigating port disruption risks.  相似文献   

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