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1.
Increasingly, the debate on freight transport and logistics involves the challenge of sustainable development. Key objectives of sustainable or “green” freight logistics systems are the mitigation of negative environmental and human health effects of distribution operations and the realization of a major modal shift in transport preferences, while at the same time achieving internal generalized cost efficiency and quality of services. Pursuing these goals requires the introduction of a range of measures. These measures call for private and public actors to take up various initiatives and adopt policies. Usually, it is more effective to combine different actions into an integrated package of measures than to introduce single instruments in isolation.This article explores the nexus between sustainability and port hinterland container logistics. In particular, the methodology and results of an empirical analysis based on applications of a network programming tool called the “interport model” are presented and discussed. The model enables an examination of all possible effects on inland container flows and their associated internal and external costs due to public and private initiatives in the field of port hinterland container logistics. The empirical analysis aims to evaluate the impact of a set of simultaneous policy options and operational measures on the competitiveness and sustainability of hinterland multimodal distribution of import and export containers handled at the seaports of the Campania region located in Southern Italy. The loading units can transit through the dry port facilities (the so called “interports”) located in the same region and/or through extra regional railway terminals, before reaching their ultimate inland destinations or the seaports. The integrated package of measures simulated by means of the model includes: (i) infrastructure policy, (ii) improvements of rail services, (iii) regulatory changes in terms of customs authorizations and procedures, (iv) removal of technical and legal barriers to fair and non-discriminatory competition in the market of rail traction between regional seaports and interports, (v) new business models integrating container logistics operations between seaports and interports, and (vi) social marginal cost charging of transport operations. Once this package of instruments is introduced, higher private and social cost efficiency of port hinterland container distribution through the investigated regional logistics system can be achieved. For instance, it has been estimated an annual saving of the order of about 12,660 tonnes of CO2 equivalent emissions from transport corresponding to an external cost reduction of 0.27 million euros from the observed real life situation, whereas the estimated saving in terms of air pollution (CO, NOx, PM, SO2, VOC) from transport is approximately 220 tonnes per year corresponding to an external benefit of 1.31 million euros.The most immediate priority appears to be the customs and intermodal logistics integration of seaports and interports by means of full implementation of the “extended gateway” concept as a way to increase the rail share of modal split and improve the overall cost efficiency of the system. In addition, the simultaneous introduction of a social marginal cost charging policy can contribute to make the regional interports a viable solution to expand the hinterland reach of the regional seaport cluster.  相似文献   

2.
Tactical planning models for liner shipping problems such as network design and fleet deployment usually minimize the total cost or maximize the total profit subject to constraints including ship availability, service frequency, ship capacity, and transshipment. Most models in the literature do not consider slot-purchasing, multi-type containers, empty container repositioning, or ship repositioning, and they formulate the numbers of containers to transport as continuous variables. This paper develops a mixed-integer linear programming model that captures all these elements. It further examines from the theoretical point of view the additional computational burden introduced by incorporating these elements in the planning model. Extensive numerical experiments are conducted to evaluate the effects of the elements on tactical planning decisions. Results demonstrate that slot-purchasing and empty container repositioning have the largest impact on tactical planning decisions and relaxing the numbers of containers as continuous variables has little impact on the decisions.  相似文献   

3.
The highly competitive and rapidly changing environment faced by businesses has greatly increased the need for strategic planning. The importance of formulating strategies to reach competitive advantages with implications in the performance is becoming increasingly evident in the seaport context. Thus, it is relevant and appropriate to apply strategic positioning tools to seaports given the role of competitive strategies in the growth and development of this industry. This research aims to analyse the strategic positioning of the leading Iberian Peninsula seaports (Portuguese and Spanish seaports) using the Boston Consulting Group (BCG) matrix as a strategic tool in an evolutionary perspective. The portfolio analysis developed subsequently focuses on the annual data of eight seaports in a selected period of 18 years (1992–2009) and on five categories of traffic: liquid bulk (LB), dry bulk (DB), containers (CO), ro-ro (roll-on/roll-off) and conventional cargo (CC). This research allows us to compare and analyse different levels of performance and identify which of the seaports have improved their strategic positioning during the considered period. The findings reveal a better positioning of Spanish seaports in relation to total traffic and that most of the seaports in the BCG matrix had changed from the first to the third period. The seaport of Valencia is the only one that has maintained its Star Performer position in all the 18 years analysed. Furthermore, considering container traffic, the results evidence the seaports of Algeciras, Valencia and Barcelona as having attained a remarkable position of leadership.  相似文献   

4.
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   

5.
Empty container management deals with repositioning empty containers at minimum costs while fulfilling empty container demands. Due to imbalances in trade, some areas have a surplus of empty containers, while others have a shortage. Therefore, empty containers need to be repositioned globally to make sure that sufficient empty containers are available everywhere. Besides, empty containers need to be repositioned regionally between shippers, consignees, inland depots, terminals and ports in order to fulfil demand. In this paper, the focus is on the empty container management problem at a regional level. The problem is described in detail and opportunities for reducing empty container movements are discussed. Decisions to be taken at each planning level (strategic, tactical and operational) are described, and for each planning level, a detailed overview of planning models proposed in the literature is presented. Planning models considering decisions at several planning levels are discussed as well. Finally, interesting opportunities for future research are identified.  相似文献   

6.
This paper formulates an inland cargo flow model that considers the additional costs incurred because of variability in shipment times at borders and seaports. Using the proposed model, five scenario analyses for cross-border haulage between Lao PDR and seaports in Thailand and Vietnam are carried out in order to assess the impact of improving border and seaport reliability. These scenario analyses show that improving shipment time variability at seaports has more impact on cost reduction compared to improving border reliability. As for seaport choice, both cases of seaport and border reliability indicate similar trends. Cargo volumes decrease at Laem Chabang seaport in Thailand and increase at Vietnamese seaports as reliability at each identified bottleneck is improved.  相似文献   

7.
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   

8.
This paper presents a new methodology to identify optimal locations and capacity for rail-based Park-and-Ride (P&R) sites to increase public transport mode share. P&R is usually taken as an important component of policies for the sustainable development of urban transport systems. However, previous studies reveal that arbitrarily determined P&R sites may act to reduce public transport commuting. This paper proposes a methodology for the optimal location and capacity design of P&R sites, with the aim of enhancing public transport usage. A Combined Mode Split and Traffic Assignment (CMSTA) model is proposed for the P&R scheme. Taking the CMSTA model as the lower level, a bi-level mathematical programming model is then built to establish the optimal location and capacity of P&R sites. A heuristic genetic algorithm is adopted to solve this model. Finally, a network example is adopted to test numerically the proposed models and algorithms.  相似文献   

9.
Rail-rail transshipment yards act as central hub nodes within a railway network and enable a rapid consolidation of containers between different freight trains. To avoid an excessive movement of gantry cranes when transferring a container from one train to another, modern yards apply sorting systems where shuttle cars move containers horizontally along the spread of the yard. This paper compares four elementary sorting systems. Specifically, we compare rubber-tired and rail-mounted shuttles and differentiate whether a pure shuttle system or a lift & shuttle system is applied. In pure shuttle systems, a shuttle receives a container from a crane and transports it towards the destination crane, where it serves as a storage device until being unloaded. A lift & shuttle system applies shuttles with an integrated lifting platform, so that they are able to autonomously store and receive containers from a separate storage rack. Both alternatives exist in rubber-tired and rail-mounted versions. As the shuttles are the main driver of the investment costs, we compare the required fleet size for timely supplying given gantry crane schedules within all four systems. For this purpose, we derive suited scheduling procedures. This way, decision support for yard managers having to identify a suited sorting system and to layout a new terminal is provided.  相似文献   

10.
The transport sector accounts for nearly one third of the world’s total energy use, while inland transport alone is responsible for half of the global petroleum consumption. The expansion of motorization in newly industrialized economies necessitates setting realistic targets. To support decision-makers in better assessment of transport sustainability performance, we introduce a systematic triple bottom line-based approach to evaluate inland transport, considering social, economic, and environmental dimensions of sustainability. The proposed network data envelopment analysis (DEA) measure organizes the three components of the system into a parallel structure, allocates shared input across subsystems, and incorporates undesirable output. The empirical application determines the efficiency of regional inland transportation systems in China from 2006 to 2015. The results indicate a rise in overall transport efficiency between China’s 11th and 12th five-year development plan periods and link the economic growth with a decrease in environmental transport efficiency in the Central and Western zones and with a decline in social efficiency in the Eastern zone. Since 2012, the social sustainability remains the weakest component of inland transport, which requires special attention by policy-makers to support vulnerable groups of transport users. This study provides further insight into the investigated measures and proposes recommendations for the improvement of inland transport in China.  相似文献   

11.
Summary

1) Western Europe has a navigable waterways‐network of about 19,000 kms. For the coming decades, however, about 40 percent of the length of these waterways has a very limited relevance, because of the small capacity of the barges that can pass along them.

2) Of the different types of barges the majority are the self‐propelled type. The importance of the pull‐towed barges is declining quickly, whereas the push‐towed barges are on the upswing.

3) The relative importance of inland shipping in comparison with rail transport is far from uniform. In The Netherlands inland shipping is dominant. On the other hand, in France, this mode of transport has only 30 percent of the total number of tons transported by inland shipping and railways together.

4) May the relative importance defer, there is a strong resemblance between the types of goods that are transported via the waterways with crude and manufactured minerals as well as building materials ranking high. In general, inland shipping is primarily involved in the transport of basic products and is of vital importance to the functioning of the West‐European economy.

5) The rather complicated legal regime of the waterways in Western Europe is certainly not the only reason why the integration in the transportation sector of the European Communities hardly moves on.

A fundamental discussion about the basic conceptions of the transport policy in the Common Market is unavoidable before real progress can be made. The entrance of the United Kingdom into the European Community may give an opening on this point.

6) Life goes on, with or without transport‐integration. Inland shipping moves forward too, paying for the use of infrastructure or not.

The general trends in transport support the expectation that the relative importance of inland shipping will increase in the coming decades. The increase in size of shipments and transport distances works in favour of this mode of transport. Besides this, inland shipping still has many possibilities to improve its productivity.

7) The future of inland shipping will be found in bulk transport and the transport of general cargo that has a volume per destination that goes far beyond the quantities for which the container or comparable types of transport units are better suited.  相似文献   

12.
Over the past decade, the escalating roadway congestion and environmental deterioration due to heavy use of private vehicles have provoked the Taiwan government to realize the importance of public transport systems. Under the “carrot-and-stick” rationales, the government has formulated public transport policies and exercised a series of related initiatives by providing sufficient and higher quality of public transport services so as to attract more private vehicle users. In this paper, the planning philosophy and policy formulation of Taiwan’s public transport development are highlighted. The most important initiatives, including the Five-year Enhancement of Mass Transportation Program and the upgrading public transport schemes in the National Development Plan are examined. Based on previous experience and lessons, we point out the most challenging issues that the government will encounter. Suggestions for the future of public transport planning are also addressed.  相似文献   

13.
M. Kia  E. Shayan  F. Ghotb 《运输评论》2013,33(1):105-122

The transport sector in general, and trucks in particular, generates a significant amount of emissions in Australia. It appears the trend will escalate unless different measures are taken to reduce the reliance of freight transport on trucks. This paper discusses the benefits of distribution centres as a means to reduce road congestion, increase safety, protect the environment by reducing atmospheric pollution and improve freight distribution. It also provides the effective use of the existing rail network and its infrastructure and improves the lead-time as well as lowering the cost of transportation of cargo. It also investigates the positive impact of distribution centres located near to manufacturing and farming production units. A simulation model has been developed and used to help determine the amount of atmospheric pollution produced by two modes of land transport, rail and road, for the movement of containers between port and destination. Results derived from the model provide evidence about a preferred land-transport regime. The paper has two sections: (1) the role of distribution centres in the chain of transport and (2) the impact of distribution centres on the environment. The first section investigates the feasibility of the implementation of distribution centres in the State of Victoria with respect to rail line capacity and location allocation. The second section presents an additional simulation model that investigates the role of a distribution centre in relation to the amount of atmospheric pollution produced by rail and road, while containers are carried between port and destination.  相似文献   

14.

As air transport demand keeps growing more quickly than system capacity, efficient and effective management of system capacity becomes essential to the operation of the future global air traffic system. Although research in the past two decades has made significant progress in relevant research fields, e.g. air traffic flow management and airport capacity modelling, research loopholes in air traffic management still exist and links between different research areas are required to enhance the system performance of air traffic management. Hence, the objective of this paper is to review systematically current research in the literature about the issue of air traffic management to prioritize productive research areas. Papers about air traffic management are discussed and categorized into two levels: system and airport. The system level of air transport research includes two main topics: air traffic flow management and airspace research. On the airport level, research topics are: airport capacity, airport facility utilization, aircraft operations in the airport terminal manoeuvring area as well as aircraft ground operations research. Potential research interests to focus on in the future are the integration between airspace capacity and airport capacity, the establishment of airport information systems to use airport capacity better, and the improvement in flight schedule planning to improve the reliability of schedule implementation.  相似文献   

15.
This paper deals with transportation technology regarding links between power unit or motor ship and ship cargo space. These links can be divided into two groups: rigid and flexible. Rigid link, established between power unit and cargo space, is dominant in maritime and road transport (sea ships and trucks), and occasionally in transport on inland waterways (self‐propelled barges). Flexible link is used in railroad transport (between the locomotive and railroad units), partially in road transport (systems with trailers and semitrailers), and in inland waterway transport (push‐towing, pulling systems and combinations of these systems). The main goal of this research is determination of possible link types and organization of fleet for transport on inland waterways in case of flexible link.  相似文献   

16.
Storage space allocation in container terminals   总被引:7,自引:0,他引:7  
Container terminals are essential intermodal interfaces in the global transportation network. Efficient container handling at terminals is important in reducing transportation costs and keeping shipping schedules. In this paper, we study the storage space allocation problem in the storage yards of terminals. This problem is related to all the resources in terminal operations, including quay cranes, yard cranes, storage space, and internal trucks. We solve the problem using a rolling-horizon approach. For each planning horizon, the problem is decomposed into two levels and each level is formulated as a mathematical programming model. At the first level, the total number of containers to be placed in each storage block in each time period of the planning horizon is set to balance two types of workloads among blocks. The second level determines the number of containers associated with each vessel that constitutes the total number of containers in each block in each period, in order to minimize the total distance to transport the containers between their storage blocks and the vessel berthing locations. Numerical runs show that with short computation time the method significantly reduces the workload imbalance in the yard, avoiding possible bottlenecks in terminal operations.  相似文献   

17.
Inland waterway transport in the Federal Republic of Germany, interconnecting 54 out of the 80 big cities, is mainly structured into small-scale enterprises. Organisation of transport, however, is mainly accommodated by a few large shipping firms. The increasing interest in inland waterway transport is due to increasing infrastructural bottlenecks in rail and road transport caused by integration, whereas waterways still have high capacity reserves. Furthermore, they are environmentally beneficial. Future problems, on the one hand, will arise from fundamental market and relating changes inland waterway transport has to adapt to within the scope of transport chain optimisation. On the other hand, the abolishment of fare regulation and the commercialisation of the railway companies will change the internal and external competitive conditions. An additional problem arises from future competition of inland vessels from Eastern European countries.  相似文献   

18.
With the substantial upsurge of container traffic, the container leasing company thrives on the financial benefits and operational flexibility of leasing containers requested by shippers. In practice, container lease pricing problem is different from the consumer product pricing in consideration of the fair value of container, limited customer types and monopolistic supply market. In view of the durability of container and the diversified lease time and quantity, the pricing is a challenging task for the leasing company. This paper examines the monopolist’s nonlinear pricing problems in static and dynamic environments. In particular, the leasing company designs and commits a menu of price and hire quantity/time pairs to maximize the expected profit and in turn customers choose hire quantities/time to maximize their surpluses according to their hire preferences. In a static environment, closed-form solutions are obtained for different groups of customers with multiple types subject to capacity constraint. In a dynamic environment, we address two customer types and derive closed-form solutions for the problem of customers with hire time preference. Further, we show that the effect of the capacity constraint increases with time of the planning horizon when customers have the same hire time preference; while in the case with different hire time preferences, the capacity constraint has opposite effects on the low and high type customers. Last, the case of customers with hire quantity preference is discussed. We focus on the lease with alternative given sets of hire time and use dynamic programming to derive the numerical optimal hire time sequence.  相似文献   

19.
Kane  Lisa  Del Mistro  Romano 《Transportation》2003,30(2):113-131
The 1990s saw the emergence of influential transport legislation both in the UK and in the USA. This "watershed" period appears to indicate that a significant turning point in transport policy is underway. There is now a need to re-evaluate how transport planning is done, and to consider changes to commonly used methods. Criticisms of urban transport planning are traced in the paper. These often focus on the four-stage modelling approach, but some authors also criticise the "rational comprehensive" paradigmatical framework within which the use of four-stage computer models is situated. It is argued that the rational comprehensive model of thinking is less useful today, due to the increasing complexity of the transport planning exercise; the rejection by the public of the transport planner as "expert"; and the highly political nature of transport planning. Alternative approaches are needed in order to address the new types of problems which transport planners face. The use of one such alternative approach, the Soft Systems Methodology, is illustrated as suitable for investigating complex decision-making systems in transport planning. It is suggested that this method could be beneficial in other problematic transport planning situations where the rational comprehensive approaches prove inadequate. Finally, the paper briefly looks ahead and considers the implications of a changing policy environment to the training of transport planners in the future.  相似文献   

20.
Abstract

Indirect effects are important considerations when making consequence analyses in general and in strategic environmental assessments in particular of potential transport solutions and infrastructure plans. The primary objective of this paper is to emphasize the need for a deeper understanding of the long‐term system effects of investments in transport infrastructure with a focus on the structuring effects that roads and railways have on society, e.g. altered transport patterns, altered settlement structures and changes in use of the built environment. Special attention is given to the following potential indirect effects: increased total transport volume, increased share of private motorists and truck transport, increased urban sprawl, and increased energy use in buildings. The conditions that determine the power of the effects are discussed and a number of key factors to be considered in transport infrastructure planning, especially in strategic environmental assessments, are suggested. Since many indirect effects emerge over time, an extended time perspective is of essence. Therefore, scenario techniques may be useful when analysing indirect effects in transport planning processes.  相似文献   

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