Several port authorities are involved in the R+D+i projects for developing port management decision-making tools. We recorded the movements of 46 ships in the Outer Port of Punta Langosteira (A Coruña, Spain) from 2015 until 2020. Using this data, we created neural networks and gradient boosting models that predict the six degrees of freedom of a moored vessel from ocean-meteorological data and ship characteristics. The best models achieve, for the surge, sway, heave, roll, pitch and yaw movements, a 0.99, 0.99, 0.95, 0.99, 0.98 and 0.98 R2 in training and have a 0.10 m, 0.11 m, 0.09 m, 0.9°, 0.11° and 0.15° RMSE in testing, all below 10% of the corresponding movement range. Using these models with forecast data for the weather conditions and sea state and the ship characteristics and berthing location, we can predict the ship movements several days in advance. These results are good enough to reliably compare the models' predictions with the limiting motion criteria for safe working conditions of ship (un) loading operations, helping us decide the best location for operation and when to stop operations more precisely, thus minimizing the economic impact of cargo ships unable to operate.

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Minimizing the stay of a vessel in port can lead to improvements in harbor efficiency. Currently, downtimes of cargo operations or their performance reduction because of excessive vessel motion are especially relevant. This work aims to evaluate the operational conditions of moored vessels in the inner port of A Coruña (Spain), comparing them with motion thresholds established by international standards for cargo operations. To this end, motions of 19 ships were monitored. Data analysis revealed large angular motions, particularly roll and yaw, including amplitudes that exceeded the limiting criteria of the standards in most of the analyzed vessels, with no registered downtime. Regarding linear movements, heave and surge recorded lower amplitudes compared to the values of standard thresholds. The specific behavior of each vessel was analyzed in terms of its size, maritime conditions, and mooring location. Field campaigns such as those performed in this work are an effective way of analyzing the operational conditions of ports, which could help in identifying problems in the mooring zone.

A set of scale-model tests carried out to enlarge the range of wave steepness values analysed in run-up, overtopping and armour layer stability studies, focusing on oblique extreme wave conditions and on their effects on a gentler slope breakwater’s trunk armour and roundhead, is presented in this paper. A stretch of a rubble mound breakwater (head and part of the adjoining trunk, with a slope of 1(V):2(H)) was built in a wave basin at the Leibniz University Hannover to assess, under extreme wave conditions (wave steepness of 0.055) with different incident wave angles (from 40º to 90º), the structure behaviour in what concerns wave run-up, wave overtopping and damage progression of the armour layer. Two types of armour elements (rock and Antifer cubes) were tested. Non-intrusive methodologies including a new application of laser scanning technique for the assessment of both armour layer damage and wave run-up and overtopping were used. It is expected that such work will contribute also with data to improve empirical formulas as well as to validate complex numerical model for wave-structure interaction.

This is the first edited volume to provide a comprehensive introduction and a critical exploration of the constructivist turn in political representation. Divided into three thematic parts, the 13 newly commissioned essays presented here develop constructivist turn as a central concept advancing the insight that there can be no democratic politics without representation because constituencies, or groups, exist as agents of democratic politics only insofar as they are represented. Complete with an original English translation of ‘Democracy and Representation’ by the French philosopher Claude Lefort, this volume delivers a rich critical intervention in democratic theory.