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The growing implementation of Decision Support Systems on modern ships, digital-twin technology, and the introduction of autonomous vessels cause the marine industry to seek accurate modeling of vessel response. Despite the contemporary 6DOF models can be used to predict ship motions in irregular waves, the impact of their stochastic realization is usually neglected and remains under-investigated. Especially in the case of turning, differences arising from the stochastic representation of the waves may result in excessive ship motions or even stability failure during maneuver execution. Therefore, in this study, statistical distributions of maximum amplitudes of roll, pitch, and lateral acceleration calculated in two representative locations on board a passenger vessel were analyzed concerning stochastic wave realization and existing extremes. The research utilized 6DOF simulation data and numerous realizations of the irregular wave with random phases of its components. Furthermore, the required number of wave realizations allowing for capturing the actual ranges of ship response at an assumed confidence level has been determined and analyzed. Ultimately, the results were compared in the safety-critical cases concerning various wave and operational conditions. The outcome of this study may be found useful by all parties involved in developing maritime autonomous systems and modeling ship motions. • The impact of stochastic wave realizations on a passenger ship's response is investigated for turning maneuver. • The ship motion parameters, i.e., the maximum amplitude of roll, pitch, and lateral accelerations are analyzed. • The realizations of irregular waves are investigated concerning various environmental and operational conditions. • The simulation-based approach is utilized to determine the required number of wave realizations. • The factors influencing minimum sample size with regard to wave stochastics are investigated. [ABSTRACT FROM AUTHOR]

In times of progressive automation of the marine industry, accurate modeling of ship maneuvers is of utmost importance to all parties involved in maritime transportation. Despite the existence of modern collision-avoidance algorithms using 6DOF motion models to predict ship trajectories in waves, the impact of stochastic realization of irregular waves is usually neglected and remains under-investigated. Therefore, herein, this phenomenon and its impact were investigated in the case study of the passenger ship's turning. To this end, statistical and spatiotemporal distributions of ship positions and corresponding trajectory parameters were analyzed. This was made using massive 6DOF simulation data with particular attention to the observed extremes. Additionally, the minimum number of wave realizations has been determined using different methods in various simulation scenarios and afterward compared concerning parameters' impact and existing dependencies. The results indicate that for simulated scenarios, the required number of wave realizations should be at least 20, but in rough seas should be greater than 30. These values satisfy an acceptable and operationally reasonable error limit reaching 15% of the ship's length overall. The obtained results may be of interest to autonomous ship developers, scholars, and marine industry representatives working on intelligent collision-avoidance solutions and ship maneuvering models. • The impact of stochastic realizations of irregular waves is investigated for the case of ship turning. • The turning circle parameters (advance, transfer, tactical diameter, max drift distance) are analyzed. • The wave realizations are analyzed concerning various environmental and operational conditions. • The bootstrap-inspired simulation method is proposed to determine the minimum sample size. • The minimum number of wave realizations is determined and analyzed for various simulation scenarios. [ABSTRACT FROM AUTHOR]