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The Maritime Labour Convention (MLC) embodies standards of existing international maritime labour conventions and recommendations, as well as the fundamental principles to be found in other international labour conventions. The aim of the convention is to address the employment standards of seafarers in the areas of fair wages, contractual terms, working and living conditions, as well as their health and safety on board ships. The purpose of this paper is to provide an in-depth study of MLC Regulation 3.1, specifically on the layout design of the accommodation spaces and possible solutions to meet the new demands as those will certainly affect the crew comfort, health and well-being on board ships.

The approach used includes a review of pre- and post-MLC conventions and regulations. This is then followed by looking at the impact of MLC Regulation 3.1 on new ship design. Possible solutions for new ship design are then proposed.

The findings from the paper were as follows: More flexibility in the form of non-mandatory guidelines and substantial equivalence under MLC. Under MLC, only Special Purpose Ship (SPS) is allowed to accommodate four persons in one room. The requirement for increased height and floor spaces would result in increased gross register tons (GT) for post-MLC built vessels. Impact due to post-MLC requirements would be more unfavourable for the design of smaller vessels below 500 GT than of bigger vessels of up to less than 3,000 GT. Possible solutions include applying for exemptions and substantial equivalents with flag states or registering with a non-ratifying flag state.

This paper has been based on a dissertation carried out for the partial fulfilment of a post-graduate degree. It has not been published in any journal.

This study aims to explore the formation mechanism of aerodynamic noise of a high-speed maglev train and understand the characteristics of dipole and quadrupole sound sources of the maglev train at different speed levels.

Based on large eddy simulation (LES) method and Kirchhoff–Ffowcs Williams and Hawkings (K-FWH) equations, the characteristics of dipole and quadrupole sound sources of maglev trains at different speed levels were simulated and analyzed by constructing reasonable penetrable integral surface.

The spatial disturbance resulting from the separation of the boundary layer in the streamlined area of the tail car is the source of aerodynamic sound of the maglev train. The dipole sources of the train are mainly distributed around the radio terminals of the head and tail cars of the maglev train, the bottom of the arms of the streamlined parts of the head and tail cars and the nose tip area of the streamlined part of the tail car, and the quadrupole sources are mainly distributed in the wake area. When the train runs at three speed levels of 400, 500 and 600 km·h⁻¹, respectively, the radiated energy of quadrupole source is 62.4%, 63.3% and 71.7%, respectively, which exceeds that of dipole sources.

This study can help understand the aerodynamic noise characteristics generated by the high-speed maglev train and provide a reference for the optimization design of its aerodynamic shape.

This paper aims to analyze the propulsive performance of small-amplitude pitching foils at very high frequencies with double objectives: to find out scaling laws for the time-averaged thrust and propulsive efficiency at very high frequencies; and to characterize the Strouhal number above which the effect of turbulence on the mean values cannot be neglected.

The thrust force and propulsive efficiency of a pitching NACA0012 foil at high reduced frequencies (k) and a Reynolds number Re = 16 000 are analyzed using accurate numerical simulations, both assuming laminar flow and using a transition turbulence model. The time-averaged results are validated with available experimental data for k up to about 12 (Strouhal number, St, up to 0.6). This study also compares the present numerical results with the predictions of theoretical models and existing numerical results. For a foil pitching about its quarter chord with amplitude α₀ = 8^o, the reduced frequency is varied here up to k = 30 (St up to 2), much higher than in any previous numerical or experimental work.

For this pitch amplitude, turbulence effects are found negligible for St ≲ 0.8, and affecting less than 10% to the time-averaged thrust coefficient CT¯ for larger St Linear potential theory fails for very large k, even for the small pitch amplitude considered, particularly for the power coefficient, and therefore for the propulsive efficiency. It is found that CT¯ ∼ St² for large St, in agreement with recent models, and the propulsive efficiency decays as 1/k, in disagreement with the linear potential theory.

Pitching foils are increasingly studied as efficient propellers and energy harvesting devices. Their performance at very high reduced frequencies has not been sufficiently analyzed before. The authors provide accurate numerical simulations to discern when turbulence is relevant for the computation of the time-averaged thrust and efficiency and how their scaling with the reduced frequency is affected in relation to the laminar-flow predictions. This is relevant because some small-amplitude theoretical models predict high propulsive efficiency of pitching foils at very high frequencies over certain ranges of the structural parameters, and only very accurate numerical simulations may decide on these predictions.