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Improved Wave-vessel Transfer Functions by Uncertainty Modelling

Nielsen, Ulrik Dam; Fønss Bach, Kasper; Iseki, Toshio

This paper deals with uncertainty modelling of wave-vessel transfer functions used to calculate or predict wave-induced responses of a ship in a seaway. Although transfer functions, in theory, can be calculated to exactly reflect the behaviour of the ship when exposed to waves, uncertainty in input variables, notably speed, draft and relative wave heading, often compromises results. In this study, uncertainty modelling is applied to improve theoretically calculated
transfer functions, so they better fit the corresponding experimental, full-scale ones. Based on a vast amount of full-scale measurements data, it is shown that uncertainty modelling can be successfully used to improve accuracy (and reliability) of theoretical transfer functions.

Nihon Kokai Gakkai Ronbunshu, 134 / 2016
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Full-shipload tramp ship routing and scheduling with variable speeds

Wen, Min; Røpke, Stefan; Petersen, H.L.; Larsen,R.; Madsen,O.B.G.

This paper investigates the simultaneous optimization problem of routing and sailing speed in the context of full-shipload tramp shipping. In this problem, a set of cargoes can be transported from their load to discharge ports by a fleet of heterogeneous ships of different speed ranges and load-dependent fuel consumption. The objective is to determine which orders to serve and to find the optimal route for each ship and the optimal sailing speed on each leg of the route so that the total profit is maximized. The problem originated from a real-life challenge faced by a Danish tramp shipping company in the tanker business. To solve the problem, a three-index mixed integer linear programming formulation as well as a set packing formulation is presented. A novel Branch-and-Price algorithm with efficient data preprocessing and heuristic column generation is proposed. The computational results on the test instances generated from real-life data show that the heuristic provides optimal solutions for small test instances and near-optimal solutions for larger test instances in a short running time. The effects of speed optimization and the sensitivity of the solutions to the fuel price change are analyzed. It is shown that speed optimization can improve the total profit by 16% on average and the fuel price has a significant effect on the average sailing speed and total profit.

Computers & Operations Research, Volume 70 / 2016
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The liner shipping berth scheduling problem with transit times

Reinhardt, Line Blander; Plum, Christian E.M.; Pisinger, David; Sigurd, Mikkel M.; Vial, Guillaume T.P.

In this paper speed optimization of an existing liner shipping network is solved by adjusting the port berth times. The objective is to minimize fuel consumption while retaining the customer transit times including the transhipment times. To avoid too many changes to the time table, changes of port berth times are only accepted if they lead to savings above a threshold value. Since the fuel consumption of a vessel is a non-linear convex function of the speed, it is approximated by a piecewise linear function. The developed model is solved using exact methods in less than two minutes for large instances. Computational experiments on real-size liner shipping networks are presented showing that fuels savings in the magnitude 2–10% can be obtained. The work has been carried out in collaboration with Maersk Line and the tests instances are confirmed to be representative of real-life networks.

Transportation Research Part E: Logistics and Transportation Review Volume 86 / 2016
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paper

The Role of Private Actors in Regulation of Arctic Shipping

Mitkidis, Katerina Peterkova

This article discusses the role of private regulators within the international legal framework of Arctic shipping. The role of private actors has been acknowledged both in legal scholarship and policy papers; but it has not yet been placed in the centre of attention. This article does so by analysing the role of private actors under the Polar Code and three types of private regulation — guidelines of classification societies, requirements of insurance industry and private contracting. It concludes that private actors have an essential role both in developing and effectuation of public international law and thus in achieving sustainable Arctic shipping.

Lloyd's Maritime and Commercial Law Quarterly [2016], part 4 / 2016
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Cost and time models for the evaluation of intermodal chains by using short sea shipping in the North Sea Region: The Rosyth-Zeebrugge route

López, Alba Matínez; Kronbak, J.; Jiang, Liping

This paper is framed in the context of the EU Interreg IVB North Sea Region project Food Port. In line with this project, this paper aims to define mathematically cost and time models able to provide realistic information about the performances of road haulage and of intermodal chains using short sea shipping (SSS) in the North Sea Region (NSR). The models integrate the necessary variables to establish the impact of different fleets and SSS features on the competitiveness of intermodal chains for the movement of food related goods. The models were applied to evaluate the opportunities for the success of intermodal chains using the Rosyth-Zeebrugge route. The results obtained validate the utility of the models and they suggest possible changes to the current operation of this SSS service in order to increase the marked potential possibilities for the intermodal chains through Rosyth-Zeebrugge.

International Journal of Shipping and Transport Logistics, Volume 7 / 2015
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Orchestrating Transnational Environmental Governance in Maritime Shipping

Lister, Jane; Taudal Poulsen, René; Ponte, Stefano

Maritime shipping is the transmission belt of the global economy. It is also a major contributor to global environmental change through its under-regulated air, water and land impacts. It is puzzling that shipping is a lagging sector as it has a well-established global regulatory body—the International Maritime Organization. Drawing on original empirical evidence and archival data, we introduce a four-factor framework to investigate two main questions: why is shipping lagging in its environmental governance; and what is the potential for the International Maritime Organization to orchestrate emerging private ‘green shipping’ initiatives to achieve better ecological outcomes? Contributing to transnational governance theory, we find that conditions stalling regulatory progress include low environmental issue visibility, poor interest alignment, a broadening scope of environmental issues, and growing regulatory fragmentation and uncertainty. The paper concludes with pragmatic recommendations for the International Maritime Organization to acknowledge the regulatory difficulties and seize the opportunity to orchestrate environmental progress.

Global Environmental Change, Volume 34 / 2015
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Achieving Energy Efficient Ship Operations Under Third Party Management: How Do Ship Management Models Influence Energy Efficiency?

Poulsen, René Taudal; Sornn-Friese, Henrik

Profitable energy saving measures are often not fully implemented in shipping, causing energy efficiency gaps. The paper identifies energy efficiency gaps in ship operations, and explores their causes. Lack of information on energy efficiency, lack of energy training at sea and onshore and lack of time to produce and provide reliable energy efficiency information cause energy efficiency gaps. The paper brings together the energy efficiency and ship management literatures, demonstrating how ship management models influence energy efficiency in ship operations. Achieving energy efficiency in ship operations is particularly challenging under third party ship management. Finally, the paper discusses management implications for shipping companies, which outsource ship management to third parties.

Research in Transportation Business & Management, Volume 17 / 2015
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Environmental Balance of Shipping Emissions Reduction Strategies

Zis, Thalis; North, Robin Jacob; Angeloudis, Panagiotis

Maritime shipping is regarded as the most efficient mode of transport; however, its contribution to climate change through greenhouse gas emissions and the health issues related to shipping activity near residential centers cannot be neglected. In recent years, the efforts of regulators, ship operators, and port authorities have led to actions for ship emissions reduction to improve shipping's environmental performance. This work builds on an activity-based methodology that allows the estimation of emissions and examines environmental effects of slow steaming, fuel regulations, near-port speed-reduction schemes, and cold ironing. Pollutant emissions of carbon dioxide, sulfur dioxide, nitrogen oxides, and black carbon are modeled. A linear programming model minimizes fuel consumption through speed differentiation on a shipping line's routes based on fuel costs and binding regulations in each segment of the journey. Although the examined emissions-reduction actions may have a positive regional environmental effect by cutting emissions, it is possible that additional emissions are generated elsewhere because of increased sailing speeds beyond regulated areas. Trade-offs between pollutants are observed for reduction actions that may have a positive effect on some emission species but at the same time result in additional particulate matter and black carbon emissions. The presented framework allows key actors to conduct comprehensive studies and design improved emissions reduction actions with fewer negative impacts in other areas.

Transportation Research Record, 2015;2479(1) / 2015
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Marine Structures: Future Trends and the Role of Universities

Pedersen, Preben Terndrup

This paper emphasizes some of the challenges and trends associated with the future development of marine structures. Its main focus is on ways to improve the efficiency of energy-consuming ships, and on design challenges related to energy-producing offshore structures. This paper also discusses the analysis tools that are most needed to enable sustainable designs for future ships and offshore structures. The last section of the paper contains thoughts on the role of universities in education, research, and innovation regarding marine structures. It discusses curriculum requirements for maritime-technology education, basic research activities, and international cooperation.

Engineering, Volume 1, Issue 1 / 2015
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Maritime routing and speed optimization with emission control areas

Fagerholt, Kjetil; Gausel, Nora T.; Rakke, Jørgen Glomvik; Psaraftis, Harilaos N.

Strict limits on the maximum sulphur content in fuel used by ships have recently been imposed in some Emission Control Areas (ECAs). In order to comply with these regulations many ship operators will switch to more expensive low-sulphur fuel when sailing inside ECAs. Since they are concerned about minimizing their costs, it is likely that speed and routing decisions will change because of this. In this paper, we develop an optimization model to be applied by ship operators for determining sailing paths and speeds that minimize operating costs for a ship along a given sequence of ports. We perform a computational study on a number of realistic shipping routes in order to evaluate possible impacts on sailing paths and speeds, and hence fuel consumption and costs, from the ECA regulations. Moreover, the aim is to examine the implications for the society with regards to environmental effects. Comparisons of cases show that a likely effect of the regulations is that ship operators will often choose to sail longer distances to avoid sailing time within ECAs. Another effect is that they will sail at lower speeds within and higher speeds outside the ECAs in order to use less of the more expensive fuel. On some shipping routes, this might give a considerable increase in the total amount of fuel consumed and the CO2 emissions.

Transportation Research Part C: Emerging Technologies, Volume 52 / 2015
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