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Charts, Sailing Directions (SDs) and other nautical publications constitute an information unit for the mariner. All relevant charts and publications together provide the mariner with an overview of a particular sea area. SDs are publications for voyage planning rather than for direct navigation. These days, the Electronic Chart Display Information System (ECDIS) is on the way to become a digital information system, which should comprise all information relevant for the mariner. Therefore, the integration of Sailing Directions information into the present ECDIS is necessary to obtain a comprehensive ECDIS, which makes conventional SDs and other publications superfluous.  相似文献   
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Reliable research synthesis is of high significance for a transport policy which tries to base its decisions on available empirical evidence. There is growing doubt whether the frequently used narrative approach provides a scientifically defensible way of synthesising a body of quantitative research results. The present paper demonstrates meta-analysis as a more objective and powerful alternative for this task. For this purpose evaluation data synthesised in two earlier narrative reviews on the effectiveness of work travel plans [Cairns et al. Making travel plans work: research report (former), Department for Transport, Local Government and the Regions (DTLR), London, 2002; Smarter choices—changing the way we travel. (Final report of the research project: The influence of soft factor interventions on travel demand. Research report for the Department for Transport.) London. Retrieved 1 December 2005, from , 2004] are meta-analytically re-analysed and compared with the conclusions drawn from the narrative synthesis of these data. Our meta-analyis provides only limited support for the conclusion that addressing parking is the hallmark of successful work travel plans. Our meta-analysis indicates that site and organisational factors as well as characteristics of the monitoring process are significant predictors of effective work travel plans, whereas Cairns et al. view little evidence for the impact of these factors.  相似文献   
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Despite significant efforts to improve environmental safety in marine oil transportation, the risk of a major accident with devastating oil spills has most likely increased. Building on the regime analytical approach where it is assumed that international collaboration may benefit participating countries, it is argued that bilateral and sub-regional initiatives may increase maritime safety significantly, compared to exclusive reliance on universal conventions. A distinction is made between on the one hand investments in safety-increasing infrastructure and local capacity building and on the other, vessel design, on-board installations and crew qualifications. It is suggested that bilateral and sub-regional initiatives are more likely to be taken on the former kind of objects, targeting issues, such as modernization of port facilities, monitoring support, assistance in emergency capacity building and designation of ports of refuge, because the interaction between the involved countries are comparably stable in the cases. Actual efforts to improve safety seem to follow the logic of separation between these two types of safety-increasing measures. It is concluded that similar drivers of bilateral and sub-regional initiatives targeting specific aspects of marine safety and contributing to overall collective benefits from improved environmental protection probably exist also in other regions than the Baltic Sea.  相似文献   
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Abstract

The negative impacts of transport are in general associated with costs. These costs are usually denoted as ‘external costs’ or ‘externalities’. This paper presents a tool for calculating external costs for freight transport together with its application to a number of case studies. The categories considered include: air pollution, greenhouse gases, noise, accidents and congestion. Results are presented for a number of different transport alternatives as total costs and divided into categories. The uncertainties in the results are discussed. The assessment of these costs is essential for predicting future transport costs.  相似文献   
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ABSTRACT

Solving the berth allocation problem (BAP) in ports is not trivial where the berth resources are limited and various sizes of vessels arrive with dramatically dissimilar loads. Especially in real scenarios, arriving vessels are accepted for a berth with the first come first served (FCFS) priority rule. This study proposes a decision support system coupled with a simulation optimization module based on the swarm-based Artificial Bee Colony optimization algorithm for solving the BAP. The proposed methodology was implemented for the Izmir port in Turkey. To investigate the influences of the vessel priorities on the BAP, four different experimental scenarios based on the single (SQM) and multiple queue models (MQM) were coupled with FCFS and proposed hybrid queue priority (HQP) rule. The results indicated that SQM scenarios were superior to MQM scenarios in a manner of minimizing the average vessel waiting times and the implementation of a dynamic berth allocation strategy for the MQM significantly decreases the vessel waiting times. Results of the SQM also imply that utilization of the HQP approach further minimizes the average vessel waiting times and increases the berth utilization and port throughput without yielding excessive waiting times for the larger vessels compared with the FCFS priority rule.  相似文献   
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Ships use propulsion machinery systems to create directional thrust. Sailing in ice-covered waters involves the breaking of ice pieces and their submergence as the ship hull advances. Sometimes, submerged ice pieces interact with the propeller and cause irregular fluctuations of the torque load. As a result, the propeller and engine dynamics become imbalanced, and energy propagates through the propulsion machinery system until equilibrium is reached. In such imbalanced situations, the measured propeller shaft torque response is not equal to the propeller torque. Therefore, in this work, the overall system response is simulated under the ice-related torque load using the Bond graph model. The energy difference between the propeller and propeller shaft is estimated and related to their corresponding mechanical energy. Additionally, the mechanical energy is distributed among modes. Based on the distribution, kinetic and potential energy are important for the correlation between propeller torque and propeller shaft response.  相似文献   
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