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The overtopping-inundation process of a tsunami results in the collisions of drifting objects on the coast, which damage structures, thereby increasing the risk of collapse. This study conducted laboratory experiments on the collision between a drifting container caused by the overtopping-inundation process of a solitary wave and a fixed port crane's leg. The movement trajectory and velocity of the container as well as the collision velocity by solitary wave inundation, were analyzed using motion analysis software. Overall, increasing solitary wave scale, collision velocity, and drifting object weight and decreased distance between the two objects tended to increase the collision force. However, different experiment results were also obtained due to pitching in objects that fully floated without bottom friction owing to the solitary wave bore. This resulted in line-to-surface collisions. Thus, surface-to-surface contact occurred under the incomplete floating condition owing to the difficulty because of interference with the bottom; however, the collision force decreased under complete floating conditions owing to line-to-surface contact. Therefore, the contact condition according to the floating behavior must be considered a parameter while predicting the collision forces of drifting objects. Thus, surface-to-surface contact occurred under the incomplete floating condition owing to the difficulty because of interference with the bottom; however, the collision force decreased under complete floating conditions owing to line-to-surface contact. Therefore, the contact condition according to the floating behavior must be considered a parameter while predicting the collision forces of drifting objects. [ABSTRACT FROM AUTHOR]

For a model incorporating the effect of a common environment on several components of a system, a multivariate Lomax distribution (MLD) is generally considered by mixing exponential variables. Objective Bayesian has very good frequentist properties and provides a moderate solution for the prior elicitation which is one of important and difficult issues on Bayesian analysis. In this paper, we develop noninformative priors, such as the probability matching priors and reference priors, for the parameters of the MLD. We proved that a reference prior for the shape parameter is a first-order probability matching prior, but the reference priors for the scale parameters do not satisfy the first-order matching criterion. In addition, a second-order probability matching prior does not exist for all parameters. We also presented the conditions that make the posterior distributions for the general prior, including the probability matching prior and reference priors, to be proper. In particular, Jeffreys' prior and probability matching priors for all parameters give proper posteriors, whereas reference priors for scale parameters give improper posteriors. [ABSTRACT FROM AUTHOR]

Appropriate estimation and prediction of wave overtopping discharges are very important in terms of economics, port structure stability, and port operation. In recent years, machine learning (ML) techniques, which predict by finding statistical structures from input/output data using computers, have generated interest. However, as the complexity of ML models increases, interpreting their results becomes increasingly difficult. Interpretation of ML results is an important part in developing an efficient structure design strategy for improved wave overtopping discharge estimation. Therefore, in this study, eight linear/nonlinear ML models were applied to the same data, and a pipeline model for selecting an ML model suitable for data characteristics was developed. In addition, the importance of variables related to the prediction of wave overtopping discharges and their correlations were analyzed by interpretable ML. The research results showed that the extreme gradient boosting model had the highest prediction accuracy and significantly reduced the error. Accordingly, a data-based model can be a new alternative for analyzing the complex physical relationships in the field of coastal engineering and used as a starting point toward structure design and development for coastal disaster prevention. [ABSTRACT FROM AUTHOR]