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‘I See You on My Radar’: Displays of the Confirmatory Form in Maritime Technologically Mediated Interaction

Froholdt, Lisa Loloma

This article investigates how speakers in maritime technologically mediated interaction utilize pre-scripted interaction. The analysis uses micro-analytical methods that have not been used in the analysis of maritime interactions since the study by Bailey et al. (2006). In contrast to Bailey et al. (2006) who have analysed interactions between co-located speakers on board ships, this article analyses interactions between speakers who are not co-located. Micro-analytical methods can shed light on sense-making practices that speakers display in pre-scripted user-device interaction as pointed out by Arminen (2005). The article advances the observations of Bailey et al. (2006) regarding the ‘confirmatory form’ that they found predominant in co-located bridge team interaction. A ‘confirmatory form’ is a speaker display of the pre-script1 called a ‘readback’ (IMO SMCP, 2001), that speakers show when verifying information. The analysis shows that the structure of the ‘readback’ is used by speakers, is dependent on reflexive user-device interaction and involves a situated rule-following (Wittgenstein, 1958). The article then argues against the findings in The MARCOM Project (1999) that advocates that spoken interaction should be done away with completely as a way of promoting safe navigation, and concurs with studies in aviation research, that show how verbal interaction is an essential part of the situated understanding that takes place when performing institutional tasks (Sanne, 2003; Nevile, 2004a; Falzon, 2008, 2009).

The Sociological Review. 2016;64(3) / 2016
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‘Swinging on the Anchor’: The Difficulties in Achieving Greenhouse Gas Abatement in Shipping Via Virtual Arrival

Poulsen, René Taudal; Sampson, Helen

The abatement of greenhouse gas emissions represents a major global challenge and an important topic for transportation research. Several studies have argued that energy efficiency measures for virtual arrival and associated reduced anchorage time can significantly reduce emissions from ships by allowing for speed reduction on passage. However, virtual arrival is uncommon in shipping. In this paper, we examine the causes for waiting time for ships at anchor and the limited uptake of virtual arrival. We show the difficulties associated with the implementation of virtual arrival and explain why shipping is unlikely to achieve the related abatement potential as assumed by previous studies. Combining onboard observations with seafarers and interviews with both sea-staff and shore-based operational personnel we show how charterers’ commercial priorities outweigh the fuel saving benefits associated with virtual arrival. Moreover, we demonstrate how virtual arrival systems have unintended, negative consequences for seafarers in the form of fatigue. Our findings have implications for the IMO’s greenhouse gas abatement goals.

Transportation Research. Part D: Transport & Environment, Volume 73 / 2019
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“Nowhere near Somalia, Mom”: On Containerizing Maritime Piracy and Being Good Men

Mannov, Adrienne

Just as containerized goods appear to flow seamlessly across the planet's oceans, internationalized and standardized certificates present seafaring labor as uniform and seamless. But underneath these certificates are the intimate and unequal entanglements of local masculinity norms, age, and kinship ties that sustain the maritime labor supply chain. In this article, we follow how three young, male seafarers from eastern India find ways to contain piracy risks at work and poverty risks at home, and their sense of obligation as men, sons, husbands, and fathers. By delving into the unequal conditions for industrial male workers from the Global South, this article demonstrates how containerized maritime labor commodities are not uniform but are dependent upon economic inequality and intimate kinship ties to be productive.

Focaal—Journal of Global and Historical Anthropology 89 (2021): / 2021
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“The helm is lost!”: Reframing psychological matters in non-routine technologically mediated interaction in a maritime context

Froholdt, Lisa Loloma

The maritime industry is a dangerous and highly technologicallysaturated sector. Unfortunately, advancement in automation and technologyhave not minimised human error as intended. Interaction between humansand technology in the industry is also overtly pre-scripted. The main reasonfor this is to reduce human error by ensuring predictability in interaction.Ultimately, investigations of non-routine interaction are often based on a hind-sight view of what went wrong in a given situation. This article analyses acollection of non-routine interactions that derive from a larger data corpus,using Discursive Psychology and Conversation Analysis. It argues that such astudy can capture what is missing from some investigations, namely, whatmakes sense for crews in the context of a given non-routine situation. Despitethe constraints and the challenges of technological complexity, this articleargues that reframing psychological matters in non-routine technologicallymediated interaction can be a new way of showing how such matters aredynamic, visible and manageable. This can inform the general debate of howto minimise human error, and more specifically, provide insight into the increas-ing inclusion of technology and as a consequence, the equally increasingamount of technologically mediated interaction that we will see in the future.

Text & Talk, 39(2) / 2019
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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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A branch-and-price algorithm to solve the integrated berth allocation and yard assignment problem in bulk ports

Robenek, Tomáš; Umang, Nitish; Bierlaire, Michel; Ropke, Stefan

In this research, two crucial optimization problems of berth allocation and yard assignment in the context of bulk ports are studied. We discuss how these problems are interrelated and can be combined and solved as a single large scale optimization problem. More importantly we highlight the differences in operations between bulk ports and container terminals which highlights the need to devise specific solutions for bulk ports. The objective is to minimize the total service time of vessels berthing at the port. We propose an exact solution algorithm based on a branch and price framework to solve the integrated problem. In the proposed model, the master problem is formulated as a set-partitioning problem, and subproblems to identify columns with negative reduced costs are solved using mixed integer programming. To obtain sub-optimal solutions quickly, a metaheuristic approach based on critical-shaking neighborhood search is presented. The proposed algorithms are tested and validated through numerical experiments based on instances inspired from real bulk port data. The results indicate that the algorithms can be successfully used to solve instances containing up to 40 vessels within reasonable computational time.

European Journal of Operational Research, Volume 235 / 2014
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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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A concise account of techniques available for shipboard sea state estimation

Nielsen, Ulrik Dam

This article gives a review of techniques applied to make sea state estimation on the basis of measured responses on a ship. The general concept of the procedures is similar to that of a classical wave buoy, which exploits a linear assumption between waves and the associated motions. In the frequency domain, this assumption yields the mathematical relation between the measured motion spectra and the directional wave spectrum. The analogy between a buoy and a ship is clear, and the author has worked on this wave buoy analogy for about fifteen years. In the article, available techniques for shipboard sea state estimation are addressed, but with a focus on only the wave buoy analogy. Most of the existing work is based on methods established in the frequency domain but, to counteract disadvantages of the frequency-domain procedures, newer studies are working also on procedures formulated directly in the time domain. Sample results from several studies are included, and the main findings from these are mentioned.

Ocean Engineering, Volume 129 / 2017
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A Decomposition Method for Finding Optimal Container Stowage Plans

Roberti, Roberto and Mingozzi, Aristide

In transportation of goods in large container ships, shipping industries need to minimize the time spent at ports to load/unload containers. An optimal stowage of containers on board minimizes unnecessary unloading/reloading movements, while satisfying many operational constraints. We address the basic container stowage planning problem (CSPP). Different heuristics and formulations have been proposed for the CSPP, but finding an optimal stowage plan remains an open problem even for small-sized instances. We introduce a novel formulation that decomposes CSPPs into two sets of decision variables: the first defining how single container stacks evolve over time and the second modeling port-dependent constraints. Its linear relaxation is solved through stabilized column generation and with different heuristic and exact pricing algorithms. The lower bound achieved is then used to find an optimal stowage plan by solving a mixed-integer programming model. The proposed solution method outperforms the methods from the literature and can solve to optimality instances with up to 10 ports and 5,000 containers in a few minutes of computing time.

Transportation Science Vol. 52, No. 6: 1297-1588 / 2018
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A Decomposition Method for Finding Optimal Container Stowage Plans

Roberti, R; Pacino, Dario

In transportation of goods in large container ships, shipping industries need to minimize the time spent at ports to load/unload containers. An optimal stowage of containers on board minimizes unnecessary unloading/reloading movements, while satisfying many operational constraints. We address the basic container stowage planning problem (CSPP). Different heuristics and formulations have been proposed for the CSPP, but finding an optimal stowage plan remains an open problem even for small-sized instances. We introduce a novel formulation that decomposes CSPPs into two sets of decision variables: the first defining how single container stacks evolve over time and the second modeling port-dependent constraints. Its linear relaxation is solved through stabilized column generation and with different heuristic and exact pricing algorithms. The lower bound achieved is then used to find an optimal stowage plan by solving a mixed-integer programming model. The proposed solution method outperforms the methods from the literature and can solve to optimality instances with up to 10 ports and 5,000 containers in a few minutes of computing time.

Transportation Science 52 (6) 1444-1462 / 2018
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