Fibre-based modelling for predicting the progressive collapse of cylindrical shells under combined axial compression and bending moment
Abstract Cylindrical shell is a fundamental building block of many engineering structures. They are usually designed to be the primary load-carrying components to withstand different combinations of environmental loads. This paper presents a fibre-based approach to modelling the progressive collapse of cylindrical shells under combined axial compression and bending moment. In this method, the progressive […]
Uncertainty of ship hull girder ultimate strength in global bending predicted by Smith-type collapse analysis
Abstract The engineering modelling of ship hull girder strength usually consists of global and local levels. The Smith-type progressive collapse method is a typical example of this kind, in which the global model requires input from the local model with the underpinning local structural behaviour, i.e., load-shortening curve (LSC). However, the modelling is prone to […]
Variable Indexing Method in Rule Documents for Ship Design Using Extraction of PDF Elements
Abstract Design rules for ships have become more extensive and detailed due to an increase in the sizes of ships. Several variables and equations used in the rules are complex, thereby impeding their review by reviewers due to their voluminosity. In addition, because these rules are constantly revised, professional investigators may miss these changes. To […]
Prediction of the Superiority of the Hydrodynamic Performance of Hull Forms Using Deep Learning
Abstract When designing a ship's hull form, a designer creates various candidate hull forms and performs a Computational Fluid Dynamics (CFD) analysis to evaluate the performance of each candidate. Designers consider quantitative indicators, such as the total resistance and wake coefficient, and qualitative indicators, such as the wave height and pressure distributions, when evaluating the […]
Study on numerical PMM test and its application to KCS hull
Abstract The planar motion mechanism (PMM) test is among the most popular methods to evaluate ship manoeuvrability due to its ability to generate manoeuvring coefficients through a series of captive tests. As a replacement for conventional towing tank facilities, the present work applies an open-source-based computational fluid dynamics (CFD) solver to conduct numerical tests, including […]
Identification of 4-DoF maneuvering mathematical models for a combatant in intact and damaged conditions
Abstract This article introduces the process of identifying the dynamics models of a combatant in intact and damaged condition based on the measured data from free running model tests. The applied system identification method is an Estimation-Before-Modeling approach, which estimates state variables and parameters separately. After estimating the states, the tendency of the hydrodynamic force acting on […]
Enhanced Convolutional Neural Network for In Situ AUV Thruster Health Monitoring Using Acoustic Signals
Abstract As the demand for ocean exploration increases, studies are being actively conducted on autonomous underwater vehicles (AUVs) that can efficiently perform various missions. To successfully perform long-term, wide-ranging missions, it is necessary to apply fault diagnosis technology to AUVs. In this study, a system that can monitor the health of in situ AUV thrusters […]
Estimation of Acoustic Channel Impulse Response at Low Frequencies Using Sparse Bayesian Learning for Nonuniform Noise Power
Abstract Sparse Bayesian learning (SBL) has been extended to estimate acoustic channel impulse responses (CIRs) at low frequencies, where matched filter (MF)-based CIR estimation suffers from low resolution due to a limited frequency band. In this study, the extended SBL was developed to account for nonuniform noise power in a signal model for the CIR […]
Automation of Crane Control for Block Lifting Based on Deep Reinforcement Learning
Abstract In shipyards, blocks are controlled by connecting the crane and block with wires during block erection. During block lifting, if a block is not carefully controlled, it will cause damage. Block lifting using crane operation is performed by controlling the number of wires, hooks, and equalizers. Consequently, predicting stable block lifting is difficult. In […]
Simulation methodology for hydrogen liquefaction process design considering hydrogen characteristics
Abstract One promising method to improve the storage capacity of hydrogen is to liquefy it, resulting in high energy density. However, liquefying hydrogen is a challenging task because hydrogen characteristics, such as a boiling point at a cryogenic temperature and changes in equilibrium compositions of spin isomers constituting hydrogen molecules, must be considered. For a design of a hydrogen liquefaction process, it is necessary […]
