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1.
Road traffic noise is an element of outstanding importance within the overall context of environmental impact. This problem must be technically addressed from an efficient viewpoint, and solutions or alternatives should be considered by means of appropriate and consolidated procedures.Up to now, there is no regulated guideline for establishing well-founded priorities when dealing with the diverse road stretches included in the corresponding Action Plans against noise under the Environmental Noise Directive (2002/49/EC). To this end, the present study proposes a methodology to sort, by priority, road stretches identified by their noise problems and therefore requiring appropriate action. The methodology is based on the so-called “road stretch priority index” (henceforth referred to as RSPI). This index involves a number of variables (called “road stretch priority variables”) that are weighted according to their influence on the road traffic noise problem. Thus, the RSPI makes it possible to prioritize different stretches of the Action Plan. To illustrate the application of the proposed methodology, this paper also describes a real case entailing a difficult choice, applying the proposed methodology to a review of the Action Plan against Noise 2008–2012 in the province of Almería, for the road network of the regional government of Andalusia, Spain.  相似文献   

2.
Abstract

A number of studies have been carried out on the factors determining port choice, derived from the perspectives of shippers, carriers or both. Recently, some studies using multi-criteria analysis, more specifically Saaty's analytical hierarchy process (AHP), have been undertaken to address port competitiveness and port selection by shipping lines. Based on a review of the literature on port selection, this article proposes a decision support system (DSS) for port selection using AHP methodology. The proposed DSS is web-based and thus it can be accessed by more decision makers and data collection can be carried out faster. Moreover, AHP addresses the issue of how to structure a complex decision problem, identify its criteria, measure the interaction among them and finally synthesise all the information to arrive at priorities, which depict preferences. AHP is able to assist port managers in obtaining a detailed understanding of the criteria and address the port selection problem utilising multi-criteria analysis. This article presents the architecture and the port selection procedure of the web-based DSS, and then illustrates three different cases. It shows how technology advancement can bring positive effects of strategic planning to shipping firms.  相似文献   

3.
Abstract

Hybrid choice modelling approaches allow latent variables in mode choice utility functions to be addressed. However, defining attitude and behavior as latent variables is influenced by the researcher's assumptions. Therefore, it is better to capture the effects of latent behavioral and attitudinal factors as latent variables than defining behaviors and attitudes per se. This article uses a hybrid choice model for capturing such latent effects, which will herein be referred to as modal captivity effects in commuting mode choice. Latent modal captivity refers to the unobserved and apparently unexplained attraction towards a specific mode of transportation that is resulting from latent attitude and behavior of passengers in addition to the urban transportation system. In empirical models, the latent modal captivity variables are explained as functions of different observed variables. Empirical models show significant improvement in fitting observed data as well as improved understanding of travel behavior.  相似文献   

4.
ABSTRACT

Governments require decision tools to deal with road traffic accidents, a pandemic resulting in millions of deaths around the world. Evidence shows that human factors are one of the major causes of road accidents, and there is much interest in identifying variables that may have an impact on drivers’ perception of risk. To this aim, we design a stated choice experiment with eight hypothetical driving scenarios considering attributes that have been strongly associated with increased accident risks: (i) driving speed, (ii) driving the wrong way in a one-way street, (iii) overtaking on a bend, and (iv) driving under the influence of alcohol or drugs. Data from a sample of survey respondents are used to estimate a hybrid discrete choice model incorporating two latent variables, Driver Concentration and Safe Driving. Our results may contribute to the design of public policies geared to prevent accidents by encouraging safer driving behaviour.  相似文献   

5.
ABSTRACT

The growing availability of geotagged big data has stimulated substantial discussion regarding their usability in detailed travel behaviour analysis. Whilst providing a large amount of spatio-temporal information about travel behaviour, these data typically lack semantic content characterising travellers and choice alternatives. The inverse discrete choice modelling (IDCM) approach presented in this paper proposes that discrete choice models (DCMs) can be statistically inverted and used to attach additional variables from observations of travel choices. Suitability of the approach for inferring socioeconomic attributes of travellers is explored using mode choice decisions observed in London Travel Demand Survey. Performance of the IDCM is investigated with respect to the type of variable, the explanatory power of the imputed variable, and the type of estimator used. This method is a significant contribution towards establishing the extent to which DCMs can be credibly applied for semantic enrichment of passively collected big data sets while preserving privacy.  相似文献   

6.
Container liner shipping companies only partially alter their shipping networks to cope with the changing demand, rather than entirely redesign and change the network. In view of the practice, this paper proposes an optimal container liner shipping network alteration problem based on an interesting idea of segment, which is a sequence of legs from a head port to a tail port that are visited by the same type of ship more than once in the existing shipping network. In segment-based network alteration, the segments are intact and each port is visited by the same type of ship and from the same previous ports. As a result, the designed network needs minimum modification before implementation. A mixed-integer linear programming model with a polynomial number of variables is developed for the proposed segmented-based liner shipping network alternation problem. The developed model is applied to an Asia–Europe–Oceania liner shipping network with a total of 46 ports and 11 ship routes. Results demonstrate that the problem could be solved efficiently and the optimized network reduces the total cost of the initial network considerably.  相似文献   

7.
ABSTRACT

This paper describes the development of railway station choice models suitable for defining probabilistic station catchments. These catchments can then be incorporated into the aggregate demand models typically used to forecast demand for new rail stations. Revealed preference passenger survey data obtained from the Welsh and Scottish Governments was used for model calibration. Techniques were developed to identify trip origins and destinations from incomplete address information and to automatically validate reported trips. A bespoke trip planner was used to derive mode-specific station access variables and train leg measures. The results from a number of multinomial logit and random parameter (mixed) logit models are presented and their predictive performance assessed. The models were found to have substantially superior predictive accuracy compared to the base model (which assumes the nearest station has a probability of one), indicating that their incorporation into passenger demand forecasting methods has the potential to significantly improve model predictive performance.  相似文献   

8.
ABSTRACT

This study estimated the external cost of air pollution from shipping by means of a meta-regression analysis, which has not been made before. Three pollutants, which were included in most of the primary studies, were considered: nitrogen oxides (NOx), sulphur dioxides (SO2) and particulate matters with a diameter of max 2.5 micrometres (PM2.5). All primary studies included damages of health and a majority added impacts on agriculture and estimated the cost of air pollutants by transferring cost estimates from studies on costs of air emissions from transports in Europe. Different regression models and estimators were used and robust results were found of statistically significant emission elasticities of below one, i.e. total external costs increase by less than 1% when emissions increase by 1%. There was a small variation between the pollutants, with the highest elasticity for PM2.5 and lowest for NOx. Calculations of the marginal external cost of the pollutants showed the same pattern, with this cost being approximately six times higher for PM2.5 than for the other pollutants. Common to all pollutants was that the marginal external cost decreases when emission increases. Another robust result was a significant increase in the cost of studies published in journals compared with other publication outlets. These findings point out some caution when transferring constant external unit cost of air pollutant from shipping, which is much applied in the literature, and the cost functions estimated in this study could thus provide a complementary transfer mechanism.  相似文献   

9.
Abstract

Since 1990s the liner shipping industry has faced a period of restructuring and consolidation, and been confronted with a continuing increase in container vessel scale. The impact of these changes is noticeable in trade patterns, cargo handling methods and shipping routes, in short ‘operations’. After listing factors influencing size, growth in container ship size is explained by economies of scale in deploying larger vessels. In order to quantify economies of scale, this paper uses the liner service cash flow model. A novelty in the model is the inclusion of +6000-20-foot Equivalent Unit (TEU) vessels and the distinction in costs between single and twin propeller units on ships. The results illustrate that scale economies have been – and will continue to be – the driving force behind the deployment of larger container vessels. The paper then assesses the link between ship size and operations, given current discussions about the increase in container vessel scale. It is found that (a) ship size and operations are linked; (b) optimal ship size depends on transport segment (deep-sea vs. short-sea shipping, SSS), terminal type (transhipment terminals vs. other terminals), trade lane (East-West vs. North-South trades) and technology; and (c) a ship optimal for one trade can be suboptimal for another.  相似文献   

10.
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.
Abstract

From the policy and management perspective, this study aims to investigate the port management tools that port/public authorities have at their disposal and then to analyse to what extent the tools are used to enforce or encourage green port development at functional activities of port operations and development. We conduct an exploratory and comparative review based on two axes: on the one hand, the range of tools available to port authorities (pricing, monitoring and measuring, market access control and environmental standard regulation) and on the other hand, the functional activities in ports (shipping traffic, cargo handling and storage operations, intermodal connection, industrial activities, and port expansion). The situations in the leading ports in Asia and Europe, namely Singapore, Shanghai, Antwerp and Rotterdam are studied and compared, whereby the policies' effectiveness is discussed accordingly. Findings show that the ports are particularly mature in exercising environmental standard regulations which reveals that the enforcement approach is more prevalent. The most focused functional activity is shipping traffic which reflects that the ports are driven by the International Maritime Organisation. The respective port authorities in Antwerp and Rotterdam have a higher level of influence on devising green port policy in comparison to the two Asian ports.  相似文献   

13.
Abstract

Numerous studies have found that suburban residents drive more and walk less than residents in traditional neighbourhoods. What is less well understood is the extent to which the observed patterns of travel behaviour can be attributed to the residential built environment (BE) itself, as opposed to attitude‐induced residential self‐selection. To date, most studies addressing this self‐selection issue fall into nine methodological categories: direct questioning, statistical control, instrumental variables, sample selection, propensity score, joint discrete choice models, structural equations models, mutually dependent discrete choice models and longitudinal designs. This paper reviews 38 empirical studies using these approaches. Virtually all of the studies reviewed found a statistically significant influence of the BE remaining after self‐selection was accounted for. However, the practical importance of that influence was seldom assessed. Although time and resource limitations are recognized, we recommend usage of longitudinal structural equations modelling with control groups, a design which is strong with respect to all causality requisites.  相似文献   

14.
Various market-based measures have been proposed to reduce CO2 emissions from international shipping. One promising mechanism under consideration is the Emission Trading Scheme (ETS). This study analyzes and benchmarks the economic implications of two alternative ETS mechanisms, namely, an open ETS compared to a Maritime only ETS (METS). The analytical solutions and model calibration results allow us to quantify the impacts of alternative ETS schemes on the container shipping sector and the dry bulk shipping sector. It is found that an ETS, whether open or maritime only, will decrease shipping speed, carrier outputs and fuel consumption for both the container and dry bulk sectors, even in the presence of a “wind-fall” profit to shipping companies. Under an open ETS, the dry bulk sector will suffer from a higher proportional reduction in output than the container sector, and will thus sell more emission permits or purchase fewer permits. Under an METS, container carriers will buy emission permits from the dry bulk side. In addition, under an METS the degree of competition within one sector will have spill-over effects on the other sector. Specifically, when the sector that sells (buys) permits is more collusive (competitive), the equilibrium permit price will rise. This study provides a framework for identifying the moderating effects of market structure and competition between firms on emission reduction schemes, and emphasizes the importance of understanding the differential impacts of ETS schemes on individual sectors within an industry when considering alternative policies.  相似文献   

15.
Abstract

It has been acknowledged that logistics is a driving force that shapes the integration of the transport chain. This paper argues that while the liner shipping industry exhibits increased horizontal integration, its vertical integration remains limited. A clear distinction is drawn between freight logistics, container logistics and vessel logistics. Freight logistics is defined as part of the supply chain process, the focus of which is the goods being transported. The purpose of container logistics is to optimize the movements of the containers themselves, an operation that is directly related to vessel logistics which is concerned with maximizing vessel utilization. The paper demonstrates that shipping lines have to find the correct balance between these three types of logistics. Their interest in vertical integration is primarily because the management of container logistics provides direct support to vessel logistics. Their involvement in freight logistics remains unclear and uncertain.  相似文献   

16.
This paper develops three game-theoretical models to analyze shipping competition between two carriers in a new emerging liner container shipping market. The behavior of each carrier is characterized by an optimization model with the objective to maximize his payoff by setting optimal freight rate and shipping deployment (a combination of service frequency and ship capacity setting). The market share for each carrier is determined by the Logit-based discrete choice model. Three competitive game strategic interactions are further investigated, namely, Nash game, Stackelberg game and deterrence by taking account of the economies of scale of the ship capacity settings. Three corresponding competition models with discrete pure strategy are formulated as the variables in shipment deployment are indivisible and the pricing adjustment is step-wise in practice. A ɛ -approximate equilibrium and related numerical solution algorithm are proposed to analyze the effect of Nash equilibrium. Finally, the developed models are numerically evaluated by a case study. The case study shows that, with increasing container demand in the market, expanding ship capacity setting is preferable due to its low marginal cost. Furthermore, Stackelberg equilibrium is a prevailing strategy in most market situations since it makes players attain more benefits from the accommodating market. Moreover, the deterrence effects largely depend on the deterrence objective. An aggressive deterrence strategy may make potential monopolist suffer large benefit loss and an easing strategy has little deterrence effect.  相似文献   

17.
Abstract

Effective management of interfaces between procurement, supply, production and distribution for higher efficiency in the supply chain is an important issue in global manufacturing, where the synchronization of production and transportation planning represents important savings in operational costs. This paper focuses on the synchronization of production planning and transportation planning in a production distribution network, where transportation is subcontracted to a professional transportation enterprise (PTE) for vehicle-hiring. Dynamic and flexible numbers of vehicles are used to cater for fast changing market demands. Thus, the number of vehicles to be hired is viewed from the planning point of view as an operational decision considered simultaneously with production and transportation planning. A mathematical model – SPTP/MTDS – for synchronized production and transportation planning under multiple times and direct shipping strategy (MTDS) is discussed, and a Lagrange relaxation decomposition-based two layer decision procedure (LRD-TLDP) is developed. By introducing artificial decision variables and Lagrange multipliers, SPTP/MTDS is decomposed into a production decision sub-problem (SPTP-PD), and a distribution decision sub-problem (SPTP-DD). A priority-based assignment heuristic and a partial chain-based genetic algorithm are developed to solve SPTP-PD and SPTP-DD, respectively. An illustration of the application of the model in an electronic appliance manufacturing enterprise in China is presented.  相似文献   

18.
ABSTRACT

Many people use public transportation systems to reach their destination, while others use personal vehicles. Poor transportation systems do not attract ridership. Therefore, the usage of passenger cars increases, and traffic and environmental conditions deteriorate. Efficient public transportation has been recognized as one of the potential ways of mitigating air pollution, reducing energy consumption, improving mobility and alleviating traffic congestion. The objective of this study is to optimize a bus feeder service that provides the shuttle service between a recreation center (e.g. Sandy Hook, NJ) and a major public transportation facility, subject to site-specific constraints such as vehicle schedules, bus availability, service capacity and budget. The decision variables include bus headway, vehicle size and route choice. The solution methodology integrating both analytical and numerical techniques is developed, which optimizes the decision variables. Finally, the proposed solution methodology is applied to a case study. Numerical results, including optimal solutions and sensitivity analyses, are presented while the level of coordination between the feeder service and a major transportation service is discussed.  相似文献   

19.
Hadi Ghaderi 《运输评论》2019,39(1):152-173
ABSTRACT

The maritime industry has been continuously transforming the nature of its business and striving to embrace technology in many aspects. In this context, autonomous technologies have been receiving momentum with a potential to revolutionise the landscape of shipping industry. After conducting a comprehensive literature review on the issues facing by the short sea shipping (SSS) industry, a model is developed to explore the potential savings of removing crew and use of autonomous technologies through a Continuously Unmanned Ship (CUS) that is operated by a Shore Control Centre (SCC). The analysis shows that autonomous technologies are viable to the challenges that the shipping industry is facing in terms of crew costs and skill shortage. To validate this statement, a case study is selected and various scenarios were tested based on relevant operational and financial considerations, including crew arrangement, cargo utilisation levels and shore wage coefficients. The results suggest that the savings occur in demand-uncertain markets and where a network of vessels are operated via a control centre. While autonomous technology use in shipping holds promise, there remain several limitations that this research addresses in terms of implementation, commercial attractiveness, risk profile, legislative, workforce planning and port operations.  相似文献   

20.
P. R. Lyon 《运输评论》2013,33(4):369-391
Abstract

The freedom of the seas, or the right of innocent passage whereby the Master of a ship may proceed as and how he chooses has, in recent years, come under considerable public scrutiny. This scrutiny has resulted in an increasing intervention by land‐based authorities to limit the traditional freedoms, by means of regulating the flow of shipping movements.

This review therefore examines the reasons behind the public scrutiny and gives a history of the development of the shore‐based regulation of shipping movements, with examples of international, national and local measures taken. The effectiveness of such measures in terms of reducing accidents is discussed, drawing upon the results of surveys undertaken in a number of countries.

This, in turn, suggests criteria for determining the degree and type of shore‐based intervention appropriate to a given waterway, and permits certain conclusions to be drawn. Finally, future developments now under discussion are described, with a commentary on further developments now possible with modern technology.  相似文献   

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