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Stochastic Model Predictive Energy Management in Hybrid Emission-Free Modern Maritime Vessels

Banaei, Mohsen; Boudjadar, Jalil; Khooban, Mohammad Hassan

Increasing concerns related to fossil fuels have led to the introducing the concept of emission-free ships (EF-Ships) in marine industry. One of the well-known combinations of green energy resources in EF-Ships is the hybridization of fuel cells (FCs) with energy storage systems (ESSs) and cold-ironing (CI). Due to the high investment cost of FCs and ESSs, the aging factors of these resources should be considered in the energy management of EF-Ships. This article proposes a nonlinear model for optimal energy management of EF-Ships with hybrid FC/ESS/CI as energy resources considering the aging factors of the FCs and ESSs. Total operation costs and aging factors of FCs and ESSs are chosen as problem objectives. Moreover, a stochastic model predictive control method is adapted to the model to consider the uncertainties during the optimization horizon. The proposed model is applied to an actual case test system and the results are discussed.

IEEE Transactions on Industrial Informatics ( Volume: 17, Issue: 8, Aug. 2021) / 2021
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Energy Management of Hybrid Diesel/Battery Ships in Multidisciplinary Emission Policy Areas

Banaei, Mohsen; Ghanami, Fatemeh; Rafiei, Mehdi; Boudjadar, Jalil; Khooban, Mohammad Hassan

All-electric ships, and especially the hybrid ones with diesel generators and batteries, have attracted the attention of maritime industry in the last years due to their less emission and higher efficiency. The variant emission policies in different sailing areas and the impact of physical and environmental phenomena on ships energy consumption are two interesting and serious concepts in the maritime issues. In this paper, an efficient energy management strategy is proposed for a hybrid vessel that can effectively consider the emission policies and apply the impacts of ship resistant, wind direction and sea state on the ships propulsion. In addition, the possibility and impact of charging and discharging the carried electrical vehicles’ batteries by the ship is investigated. All mentioned matters are mathematically formulated and a general model of the system is extracted. The resulted model and real data are utilized for the proposed energy management strategy. A genetic algorithm is used in MATLAB software to obtain the optimal solution for a specific trip of the ship. Simulation results confirm the effectiveness of the proposed energy management method in economical and reliable operation of the ship considering the different emission control policies and weather condition impacts.

Energies 2020, 13(16), 4179 / 2020
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A Comparative Analysis of Optimal Operation Scenarios in Hybrid Emission-Free Ferry Ships

Banaei, Mohsen; Rafiei, Mehdi; Boudjadar, Jalil; Khooban, Mohammad Hassan

The utilization of green energy resources for supplying energy to ships in the marine industry has received increasing attention during the last years, where different green resource combinations and control strategies have been used. This article considers a ferry ship supplied by fuel cells (FCs) and batteries as the main sources of ship's power. Based on the designers' and owners' preferences, different scenarios can be considered for managing the operation of the FCs and batteries in all-electric marine power systems. In this article, while considering different constraints of the system, six operating scenarios for the set of FCs and batteries are proposed. Impacts of each proposed scenario on the optimal daily scheduling of FCs and batteries and operation costs of the ship are calculated using a mixed-integer nonlinear programming model. Model predictive control (MPC) is also applied to consider the deviations from hourly forecast demand. Moreover, since the efficiency of FCs varies for different output powers, the impacts of applying a linear model for FCs' efficiency are compared with the proposed nonlinear model and its related deviations from the optimal operation of the ship are investigated. The proposed model is solved by GAMS software using actual system data and the simulation results are discussed. Finally, detailed real-time hardware-in-the-loop (HiL) simulation outcomes and comparative analysis are presented to confirm the adaptation capability of the proposed strategy.

IEEE Transactions on Transportation Electrification ( Volume: 6, Issue: 1, March 2020) / 2020
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Fault tolerant position-mooring control for offshore vessels

Blanke, Mogens; Nguyen, Dong Trong

Fault-tolerance is crucial to maintain safety in offshore operations. The objective of this paper is to show how systematic analysis and design of fault-tolerance is conducted for a complex automation system, exemplified by thruster assisted Position-mooring. Using redundancy as required by classification societies' class notations for offshore position controlled vessels, the paper shows how violations of normal behaviour of main components can be detected and isolated. Using a functional service philosophy, diagnosis procedures are auto-generated based on provable correct graph analysis methods. Functional faults that are only detectable, are rendered isolable through an active isolation approach. Once functional faults are isolated, they are handled by fault accommodation techniques to meet overall control objectives specified by class requirements. The paper illustrates the generic methodology by a system to handle faults in mooring lines, sensors or thrusters. Simulations and model basin experiments are carried out to validate the concept for scenarios with single or multiple faults. The results demonstrate that enhanced availability and safety are obtainable with this design approach. While methods are introduced at a tutorial level, the paper is original by providing a total Position-mooring system design that ensures resilience to any single fault and to selected multiple faults.

Ocean Engineering, Volume 148 / 2018
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A Base Integer Programming Model and Benchmark Suite for Liner-Shipping Network Design

Brouer, Berit D; Alvarez, J Fernando; Plum, Christian Edinger Munk; Pisinger, David; Sigurd, Mikkel M.

The liner-shipping network design problem is to create a set of nonsimple cyclic sailing routes for a designated fleet of container vessels that jointly transports multiple commodities. The objective is to maximize the revenue of cargo transport while minimizing the costs of operation. The potential for making cost-effective and energy-efficient liner-shipping networks using operations research (OR) is huge and neglected. The implementation of logistic planning tools based upon OR has enhanced performance of airlines, railways, and general transportation companies, but within the field of liner shipping, applications of OR are scarce. We believe that access to domain knowledge and data is a barrier for researchers to approach the important liner-shipping network design problem. The purpose of the benchmark suite and the paper at hand is to provide easy access to the domain and the data sources of liner shipping for OR researchers in general. We describe and analyze the liner-shipping domain applied to network design and present a rich integer programming model based on services that constitute the fixed schedule of a liner shipping company. We prove the liner-shipping network design problem to be strongly NP-hard. A benchmark suite of data instances to reflect the business structure of a global liner shipping network is presented. The design of the benchmark suite is discussed in relation to industry standards, business rules, and mathematical programming. The data are based on real-life data from the largest global liner-shipping company, Maersk Line, and supplemented by data from several industry and public stakeholders. Computational results yielding the first best known solutions for six of the seven benchmark instances is provided using a heuristic combining tabu search and heuristic column generation.

Transportation Science Vol. 48, No. 2 / 2014
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Optimization in liner shipping

Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

Seaborne trade is the lynchpin in almost every international supply chain, and about 90% of non-bulk cargo worldwide is transported by container. In this survey we give an overview of data-driven optimization problems in liner shipping. Research in liner shipping is motivated by a need for handling still more complex decision problems, based on big data sets and going across several organizational entities. Moreover, liner shipping optimization problems are pushing the limits of optimization methods, creating a new breeding ground for advanced modelling and solution methods. Starting from liner shipping network design, we consider the problem of container routing and speed optimization. Next, we consider empty container repositioning and stowage planning as well as disruption management. In addition, the problem of bunker purchasing is considered in depth. In each section we give a clear problem description, bring an overview of the existing literature, and go in depth with a specific model that somehow is essential for the problem. We conclude the survey by giving an introduction to the public benchmark instances LINER-LIB. Finally, we discuss future challenges and give directions for further research.

4OR volume 15 / 2017
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What is maritime security?

Bueger, Christian

Maritime security is one of the latest buzzwords of international relations. Major actors have started to include maritime security in their mandate or reframed their work in such terms. Maritime security is a term that draws attention to new challenges and rallies support for tackling these. Yet, no international consensus over the definition of maritime security has emerged. Buzzwords allow for the international coordination of actions, in the absence of consensus. These, however, also face the constant risk that disagreements and political conflict are camouflaged. Since there are little prospects of defining maritime security once and for all, frameworks by which one can identify commonalities and disagreements are needed. This article proposes three of such frameworks. Maritime security can first be understood in a matrix of its relation to other concepts, such as marine safety, seapower, blue economy and resilience. Second, the securitization framework allows to study how maritime threats are made and which divergent political claims these entail in order to uncover political interests and divergent ideologies. Third, security practice theory enables the study of what actors actually do when they claim to enhance maritime security. Together these frameworks allow for the mapping of maritime security.

Marine Policy, Volume 53 / 2015
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Blue crime: Conceptualising transnational organised crime at sea

Bueger, Christian; Edmunds, Timothy

Transnational organised crime at sea is a growing international concern. However, and despite its importance, the concept remains uncertain and contested. This ambiguity has led to a tendency to focus on individual challenges such as piracy or illegal fishing, rather than convergencies and synergies between and across issues, and has stymied a concerted international policy response. Debate continues over the term itself, what illicit activities it incorporates and excludes, and how these can be meaningfully conceptualised in ways that both recognise the diverse nature of the concept yet also provide a basis for an integrated response to the challenges it presents. In this paper, we address this lacuna by providing a systemic conceptualisation and analysis of transnational organised crime at sea. Our goal is to provide a firm basis for future enquiries on the different types of blue crime, to trace their distinct characteristics and identify how they intersect, and to consider what kinds of synergies can be built to respond to them. In so doing, we organise the nascent academic and policy discourse on blue criminology and maritime security to provide a new framework for navigating this complex issue for practitioners and analysts alike.

Marine Policy, Volume 119 / 2020
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Beyond seablindness: a new agenda for maritime security studies

Bueger, Christian; Edmunds, Timothy

This article examines the rise of maritime security in concept and practice. We argue that developments in the maritime arena have flown beneath the radar of much mainstream international relations and security studies scholarship, and that a new agenda for maritime security studies is required. In this article we outline the contours of such an agenda, with the intention of providing orientation and direction for future research. Our discussion is structured into three main sections, each of which outlines a core dimension of the maritime security problem space. We begin with a discussion of the issues and themes that comprise the maritime security agenda, including how it has been theorized in security studies to date. Our argument is that the marine environment needs to be understood as part of an interlinked security complex, which also incorporates strong connections between land and sea. Second, we examine the ways in which maritime security actors have responded to these challenges in practice, focusing on issues of maritime domain awareness, coordination of action, and operations in the field. Third, we turn to the mechanisms through which the new maritime security agenda is being disseminated to local actors through a process of devolved security governance. We focus particularly on efforts to distribute knowledge and skills to local actors through capacity building and security sector reform. In the conclusion, we outline the future challenges for maritime security studies that follow from these observations.

International Affairs, Volume 93, Issue 6 / 2017
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Pragmatic ordering: Informality, experimentation, and the maritime security agenda

Bueger, Christian; Edmunds, Timothy

The question of when and how international orders change remains a pertinent issue of International Relations theory. This article develops the model of pragmatic ordering to conceptualise change. The model of pragmatic ordering synthesises recent theoretical arguments for a focus on ordering advanced in-practice theory, pragmatist philosophy, and related approaches. It also integrates evidence from recent global governance research. We propose a five-stage model. According to the model, once a new problem emerges (problematisation), informality allows for experimenting with new practices and developing new knowledge (informalisation and experimentation). Once these experimental practices become codified, and survive contestation, they increasingly settle (codification) and are spread through learning and translation processes (consolidation). We draw on the rise of the maritime security agenda as a paradigmatic case and examine developments in the Western Indian Ocean region to illustrate each of these stages. The article draws attention to the substantial reorganisation of maritime space occurring over the past decade and offers an innovative approach for the study of orders and change.

Review of International Studies, 47(2) / 2021
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