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Transnationaliseringen af Maersk Line: Fra tredjepartsagenter til egne kontorer i udlandet

Sornn-Friese, Henrik

Maersk Line er verdens førende containerrederi og blandt de mest betydningsfulde virksomheder i Danmark. Den globale førerposition blev opnået på relativt kort tid og var et resultat af rederiets beslutning i 1973 om at gå helhjertet ind i containerskibsfarten. Beslutningen blev startskuddet til Maersk Lines dybe internationalisering, hvor rederiet ændrede sig fra at være en overvejende danske virksomhed, der betjente internationale markeder, til at være en genuin transnational virksomhed. Med fokus på opbygningen af Maersk Lines globale organisation og særligt etableringen af egne kontorer i udlandet indkredses rederiets tilpasning og udvikling i perioden fra 1973-1999.

Økonomi & Politik, Volume90 / 2017
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Maritime security and capacity building in the Gulf of Guinea: On comprehensiveness, gaps, and security priorities

Jacobsen, Katja Lindskov

It is widely acknowledged that maritime security in the Gulf of Guinea is a highly complex phenomenon involving a variety of issues (legal deficiencies, inadequate military equipment, and challenges like corruption, political unrest and youth unemployment) as well as a multiplicity of external responders. To make sense of the impact that external actors have when they address this complex problem through various maritime capacity building endeavours, this article argues that there is a need to understand the attractiveness of capacity building vis-à-vis the widely acknowledged need for a comprehensive approach, as well as the difficulties of translating the potential for comprehensiveness into practice (as important aspects of the problem remain largely unaddressed). Further, it is argued that it is important to appreciate that even if these gaps – i.e. the aspects that maritime capacity building currently leaves unaddressed – represent a ‘failure’ to deliver a comprehensive response, they are at the same time illustrative of how the maritime capacity building activities of various external actors also ‘succeed’ in having an impact on this regional security landscape – for instance, by influencing how certain aspects of this multifaceted problem are prioritised, whilst others are only marginally addressed, if at all.

African Security Review, 26:3 / 2017
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Adaptive Observer for Nonlinearly Parameterized Hammerstein System With Sensor Delay—Applied to Ship Emissions Reduction

Nielsen, Kræn Vodder; Blanke, Mogens; Eriksson, Lars

Taking offspring in a problem of ship emission reduction by exhaust gas recirculation control for large diesel engines, an underlying generic estimation challenge is formulated as a problem of joint state and parameter estimation for a class of multiple-input single-output Hammerstein systems with first-order dynamics, sensor delay, and a bounded time-varying parameter in the nonlinear part. This brief suggests a novel scheme for this estimation problem that guarantees exponential convergence to an interval that depends on the sensitivity of the system. The system is allowed to be nonlinear, parameterized, and time dependent, which are characteristics of the industrial problem we study. The approach requires the input nonlinearity to be a sector nonlinearity in the time-varying parameter. Salient features of the approach include simplicity of design and implementation. The efficacy of the adaptive observer is shown on simulated cases, on tests with a large diesel engine on test bed, and on tests with a container vessel.

IEEE Transactions on Control Systems Technology ( Volume: 26, Issue: 4, July 2018) / 2017
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Modelling of temporal and spatial evolution of sulphur oxides and sulphuric acid under large, two-stroke marine engine-like conditions using integrated CFD-chemical kinetics

Pang, Kar Mun; Karvounis, Nikolas; Walther, Jens Honore; Schramm, Jesper; Glarborg, Peter; Mayer, Stefan

In this work, three-dimensional computational fluid dynamics (CFD) studies of sulphur oxides (SOx) and sulphuric acid (H2SO4) formation processes in a large, low speed two-stroke marine diesel engine are carried out. The current numerical study aims to investigate the conversion of sulphuric dioxide (SO2) to sulphuric trioxide (SO3) and the possibility of H2SO4 condensation which are the prerequisites to better understand the corrosion-induced wear phenomenon. This is achieved with the aid of the implementation of a multicomponent surrogate model, which comprises a skeletal n-heptane mechanism and a reduced sulphur subset mechanism. In the present work, performance of the coupled CFD-chemical kinetic model is evaluated using both qualitative and quantitative methods. The modelling results show that the temporal and spatial evolutions of SOx predicted by the skeletal model are similar to those by the base mechanism. Predictions of the variations of SOx and the associated SO2 to SO3 conversion in response to the change of fuel sulphur content, swirl velocity, start of injection, scavenge pressure and humidity qualitatively agree with numerical and experimental results from the literature. The model is further evaluated using the measured SO2 to SO3 conversion levels in a low load, low scavenge pressure case and a low load, high scavenge pressure case. The absolute values of simulated and measured conversion levels are close, although the former appear to be higher. The current results show that the flame impinges at the cylinder liner near top dead centre. The gas is cooled rapidly by the wall temperature and H2SO4 is produced in the region where the local temperature is less than 600 K. Based on the flue gas correlation, the acid dew point temperature is higher than the wall temperature, suggesting that acid condensation may begin early at the top part of the cylinder liner. The predicted distribution corresponds well with the distribution of corroded parts observed in service engines. The model is expected to serve as an important tool to simulate the rates of SO2 absorption into lubricating oil film and H2SO4 condensation in this combustion system.

Applied Energy, Volume 193 / 2017
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The implications of the new sulphur limits on the European Ro-Ro sector

Zis, Thalis; Psaraftis, Harilaos N.

In an effort to reduce the environmental impacts of maritime transportation, the International Maritime Organization (IMO) designated special Sulphur Emission Control Areas (SECAs) where ships are required to use low-sulphur fuel. In January 2015, the sulphur limit within SECAs was lowered to 0.1%, which can only be achieved if vessels are using pricier ultra-low sulphur fuel, or invest in abatement technologies. The increased operating costs borne by Ro-Ro operators in SECAs due to the stricter limits can result in the shutting down of some routes and a redistribution of cargo flows with land-based alternatives. The exact repercussions of the new sulphur limits are difficult to identify in the wake of significant recent reductions of the fuel prices for both low-sulphur and heavy fuel oil. This paper presents a modal split model that estimates modal shifts vis-a-vis competing maritime and land-based modes available to shippers. This allows examining the implications of the recent low prices to modal choice, and the influence a potential increase in fuel prices may have. The model is applied to seven routes affected by the regulation based on data from a leading European Ro-Ro operator. Sensitivity analyses on market share data, cargo values, freight rates, and haulers rates are conducted. Emissions inventories are constructed to assess the environmental efficacy of the SECA regulation. The novelty of the proposed model lies in the examination of the ex-post implications of shutting down a service and the redistribution of transport. Recommendations to mitigate and reverse the negative side-effects of such environmental legislation are proposed.

Transportation Research Part D: Transport and Environment, Volume 52, Part A, / 2017
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Nuclear propulsion in ocean merchant shipping: The role of historical experiments to gain insight into possible future applications

Schøyen, Halvor; Steger-Jensen, Kenn

Global marine shipping annually accounts for about one billion tonnes of CO2 equivalent greenhouse gas emissions. Nuclear power propulsion may be an option to de-carbonise some niches of the merchant ocean fleet. This paper considers the three experimental nuclear-powered merchant ships launched and operated in the world so far; the iconic Savannah (USA), Otto Hahn (West Germany) and Mutsu (Japan). They were independently developed and operated in the 1960s and 1970s for technology demonstration and learning. A fourth ship, Sevmorput (Soviet Union/Russia, 1988–to date), is a pioneer in respect of its logistics functions and propulsion system. This paper develops a theoretical framework for the sustainability assessment of nuclear propulsion in ocean merchant shipping and presents a method for exploring nuclear propulsion, relative to flag state, ports, shipping resources and ocean transport services. The experimental ships’ transport efficiency is discussed and related to contemporary oil-fired shipping of general cargo, and to recent literature presenting possible future applications of merchant nuclear propulsion in some market niches. Insights provided include: (1) the experiments demonstrate that merchant nuclear propulsion may be technically feasible; (2) port and canal access for merchant nuclear-powered ships may be difficult and restricted; (3) the up-front costs, refuelling and end-of-life decommissioning costs of nuclear-powered ships are vast and uncertain against conventionally-powered ships; (4) because nuclear fuel is comparatively low-cost, the conventional oil-fired ship cost implications of high-speed operations do not apply.

Journal of Cleaner Production, Vol. 169 (2017) / 2017
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Fishers sharing real-time information about “bad” fishing locations: A tool for quota optimization under a regime of landing obligations

Soren Qvist Eliasen & Nikolaj Bichel

There is an increasing pressure on the fisheries to avoid bycatch and discards. In the EU this is seen in landing obligations in the new Common Fisheries Policy. The European fisheries are thus under pressure to be highly selective both in adjusting catches to the individual or collective quota combinations and to be size selective in order to optimize the economic outcome of the available quota. This paper proposes a strategy of time-place selectivity by sharing real-time data and information between vessels about areas with high abundance of unwanted species and sizes (hotspots). The paper examines use of time-place regulation, risks/benefits of sharing knowledge and experiences from a previous real-time information sharing system as a basis for developing the four models for fisher's sharing of information. The models differ with respect to data and information collection methods, who owns and accesses the data and hotspot warnings. The models are tested through a discussion of the possible application of the models in the context of the nephrops trawl fishery in Kattegat and Skagerrak. Based on this the models are proposed as possible tools for the fishing industry and managers when adjusted to specific local conditions, and a recommendation for policy support of development of information sharing systems is outlined.

Marine Policy / 2016
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Challenges with harmonic compensation at a remote bus in offshore wind power plant

Sanjay K. Chaudhary, Cristian Lascu, Bakhtyar Hoseinzadeh, Remus Teodorescu, Lukasz H. Kocewiak, Troels Sorensen & Christian F. Jensen

This paper investigates the challenges associated with remote harmonic compensation in offshore wind power plants through long cables and transformers. The interaction between the grid network and the wind power plant network can lead to the amplification of certain harmonics and potentially resonant conditions. Hence, the plant developer is required to maintain the harmonic distortion at the point of common coupling within the planning level limits using harmonic compensation, which is usually done by static filters. In this paper an active damping compensation strategy with a STATCOM using emulation of using emulation of resistance at the harmonic frequencies of concern is analyzed. Finally the results are demonstrated using time domain simulations in PSCAD.

IEEE / 2016
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The liner shipping berth scheduling problem with transit times

Reinhardt, Line Blander; Plum, Christian Edinger Munk; Pisinger, David; Sigurd, Mikkel; 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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Optimization of the drayage problem using exact methods

Reinhardt, Line Blander; Pisinger, David; Spoorendonk, Simon ; Sigurd, Mikkel

Major liner shipping companies offer pre- and end-haulage as part of a door-to-door service, but unfortunately pre- and end-haulage is frequently one of the major bottlenecks in efficient liner shipping due to the lack of coordination between customers. In this paper, we apply techniques from vehicle routing problems to schedule pre- and end-haulage of containers, and perform tests on data from a major liner shipping company. The paper considers several versions of the scheduling problem such as having multiple empty container depots, and having to balance the empty container depot levels. The influence of the side constraints on the overall cost is analysed. By exploring the fact that the number of possible routes in the considered case is quite limited, we show that the model can be solved within a minute by use of column enumeration. Alternative constraints and problem formulations, such as balancing empty container storage level at depots, are considered. Computational results are reported on real-life data from a major liner shipping company.

INFOR: Information Systems and Operational Research, 54:1 / 2016
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