International Journal of Naval Architecture and Ocean Engineering最新文献

{"title":"Experiment and modeling of submarine emergency rising motion using free-running model","authors":"Jooho Lee,&nbsp;Seonhong Kim,&nbsp;Jihwan Shin,&nbsp;Jaemoon Yoon,&nbsp;Jinheong Ahn,&nbsp;Minjae Kim","doi":"10.1016/j.ijnaoe.2024.100641","DOIUrl":"10.1016/j.ijnaoe.2024.100641","url":null,"abstract":"<div><div>Development of submarine and its safe operational envelope requires an understanding of motion characteristics including emergency rising motion. In this study, the emergency rising motion is investigated using submarine free-running model equipped with ballast systems. The emergency rising test was conducted according to the initial vehicle speed, yaw rate, depth, ballast water discharge ratio and time interval between bow and stern ballast systems. Experimental results reveal that the maximum pitch angle before surface is affected by initial velocity and the operation conditions of ballast systems. In addition, excessive roll occurs after the surface when the submarine passes through the water surface at a negative pitch angle. Furthermore, the system parameters that comprise the emergency rising model are estimated using the collected test data. The identified model is verified by comparing emergency rising simulation with the free-running model test results.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100641"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive review of foundation designs for fixed offshore wind turbines","authors":"Yun-jae Kim ,&nbsp;Jin Seok Lim ,&nbsp;Hae Jong Kim ,&nbsp;Sung-Woong Choi","doi":"10.1016/j.ijnaoe.2025.100643","DOIUrl":"10.1016/j.ijnaoe.2025.100643","url":null,"abstract":"<div><div>In the present study, technical challenges and their corresponding solutions for each type of foundation—gravity-based, monopile, jacket, tripod, and suction bucket—used in wind turbines were addressed with consideration to different water depths. Along with presenting challenges and their solutions for each foundation, the present study proposed optimizing solutions and methods for addressing these challenges, including numerical approaches and empirical methods derived from field testing. These include enhancing structural stability, improving installation efficiency, and utilizing advanced structural analysis techniques to predict and mitigate environmental impacts. Finally, research cases demonstrating improvements in foundations through shape modifications are summarized. This paper focuses on addressing and proposing an optimal design approach to achieve cost reduction, improved stiffness, and weight minimization. Notably, hybrid foundations incorporating friction wheels achieved a 300% increase in ultimate bearing capacity, while optimization techniques accounting for environmental loads resulted in approximately a 38.24% reduction in foundation weight.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100643"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive neural network fault-tolerant sliding mode control for ship berthing with actuator faults and input saturation","authors":"Son Tung Vu ,&nbsp;Thai Duong Nguyen ,&nbsp;Hai Van Dang ,&nbsp;Van Suong Nguyen","doi":"10.1016/j.ijnaoe.2025.100644","DOIUrl":"10.1016/j.ijnaoe.2025.100644","url":null,"abstract":"<div><div>This paper develops a robust controller for automatic ship berthing subjected to actuator faults, input saturation, modeling uncertainties, and external disturbances. First, sliding mode control (SMC) is used as a core controller to provide robust features for the ship berthing system. Second, fault-tolerant control (FTC) is combined with the controller to face the actuator faults. Third, the radial basis function (RBF) neural network is employed to approximate the modeling uncertainties while the effect of external disturbances is compensated by an adaptive control technique. In addition, an anti-saturation auxiliary system is conducted to deal with the input saturation for physical limitations of the actuators. Finally, numerical simulation and comparison of the results with the other control approaches are carried out to highlight the advantages of the proposed controller.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100644"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of notch shape on the fracture toughness behavior","authors":"Jiseung Lee ,&nbsp;Wonjun Jo ,&nbsp;Junseok Seo ,&nbsp;Gyubaek An","doi":"10.1016/j.ijnaoe.2025.100646","DOIUrl":"10.1016/j.ijnaoe.2025.100646","url":null,"abstract":"<div><div>This study evaluates the effect of notch shape on the fracture toughness of a 500 MPa base material designed for liquefied carbon dioxide storage tanks. This study specifically focuses on assessing the crack tip opening displacement (CTOD) values for different notch shapes, including fatigue pre-cracks (R = 0.025 mm) and electrical discharge machining (EDM) notches (R = 0.07 mm and R = 0.15 mm). CTOD tests were conducted over a temperature range of −55 °C to −140 °C. The results revealed that as the notch radius increased, the degree of stress concentration decreased, leading to an increase in fracture toughness. In temperature-dependent tests, CTOD values consistently decreased as the temperature decreased, with EDM notches exhibiting a lower rate of fracture toughness reduction compared to fatigue pre-cracks, which is attributed to differences in the degree of stress concentration. Scanning electron microscopy analysis of the fracture surfaces revealed the reason for significant differences in CTOD values and fracture behaviors between fatigue pre-crack and EDM notches, particularly at −140 °C, a temperature below the ductile to brittle transition temperature. This study suggests that EDM notches, especially with radii of 0.07 mm and 0.15 mm, can effectively replace fatigue pre-cracks in CTOD evaluations, particularly at temperatures above the transition temperature, offering a more efficient method for assessing fracture toughness in cryogenic environments.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100646"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning-based optimal value calculation for welding variables in AR training","authors":"Chang Sub Song ,&nbsp;Jong-Ho Nam","doi":"10.1016/j.ijnaoe.2025.100652","DOIUrl":"10.1016/j.ijnaoe.2025.100652","url":null,"abstract":"<div><div>Currently, the shipbuilding industry is experiencing a surge in orders due to the rising demand for eco-friendly ships, necessitating the optimal use of available resources for production. However, the production workforce has not fully recovered to the level required to meet these increased orders following large-scale industry restructuring. In particular, there is a shortage of highly skilled welders, and concerns are growing about the transfer of expertise due to an aging workforce and a lack of younger workers. Shipbuilders worldwide face similar challenges and are exploring various methods to transfer the tacit knowledge of skilled welders to less experienced workers, which has introduced unforeseen challenges. In this study, we develop a machine learning algorithm that suggests the optimal values of key welding variables for an AR-based welding training system designed to assist less skilled workers. We collected welding data from highly skilled workers using the FCAW (Flux-Cored Arc Welding) technique, which is commonly employed in the shipbuilding process. The welding variables that represent tacit knowledge were identified and trained using the Extra Trees Regressor model. Subsequently, a welding AR training system was implemented, allowing the trained model to guide users on the optimal values for welding variables. Finally, the effectiveness of this system in training welders was verified at a shipyard technical training center.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100652"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The extended modified Logvinovich model: Application to the water entry of two-dimensional wedges","authors":"Yang Zhang ,&nbsp;Se-Myong Chang ,&nbsp;Deuk-Joon Yum","doi":"10.1016/j.ijnaoe.2024.100631","DOIUrl":"10.1016/j.ijnaoe.2024.100631","url":null,"abstract":"<div><div>A planing craft is one of the most commonly used types for small high-performance vessels since it helps to mitigate the severe viscous friction between the ship hull and water. Therefore, it is essential to develop methods for quickly and accurately estimating the running attitude during the early design phase and in actual operational conditions. We propose the Extended Modified Logvinovich Model (EMLM) for water entry to address the flow separation problem when a wedge-shaped hull enters the free surface during motion. Utilizing a two-dimensional approximation, we analyzed the fundamental potential flow through mathematical techniques for unsteady flow. As a verification, we calculated the dynamic vertical force coefficient compared with CFD(computational fluid dynamics) based on BEM(boundary element method) and an analytic similarity solution, where the results demonstrated good agreement with experimental data for validation.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100631"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"YOLO-ESFM: A multi-scale YOLO algorithm for sea surface object detection","authors":"Maochun Wei ,&nbsp;Keyu Chen ,&nbsp;Fei Yan ,&nbsp;Jikang Ma ,&nbsp;Kaiming Liu ,&nbsp;En Cheng","doi":"10.1016/j.ijnaoe.2025.100651","DOIUrl":"10.1016/j.ijnaoe.2025.100651","url":null,"abstract":"<div><div>Environmental perception and object detection are pivotal research topics in the marine domain. The sea surface presents unique challenges, including harsh weather conditions, wave interference, and multi-scale targets, often resulting in suboptimal detection results. To address these issues, we present an innovative solution: the integration of the Efficient Scale Fusion Module (ESFM) into the advanced YOLO architecture, resulting in the enhanced model, YOLO-ESFM. The ESFM serves as both the backbone and detection head of the network, significantly improving performance compared to the baseline models in YOLOv5s, YOLOv7-tiny, and YOLOv7. Furthermore, to tackle the limitations of the CIOU in YOLOv7, we introduce an improved method, ZIOU, which has been rigorously evaluated and proven effective on the Sea Surface Target Dataset. Comparative studies demonstrate that YOLO-ESFM not only maintains efficiency in terms of parameters and FLOPs but also surpasses YOLOv7 in detection accuracy on both the Sea Surface Target Dataset and the PASCAL VOC 07+12 Dataset.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100651"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of object detection accuracy based on the density of 3D point clouds for deep learning-based shipyard datasets","authors":"Ki-Seok Jung ,&nbsp;Dong-Kun Lee","doi":"10.1016/j.ijnaoe.2025.100648","DOIUrl":"10.1016/j.ijnaoe.2025.100648","url":null,"abstract":"<div><div>3D point clouds are a crucial data format for accurately capturing geometric information in large-scale industrial environments such as shipyards. Deep learning-based object detection technology using 3D point clouds enables automated production management and process optimization. However, the large volume characteristic of 3D point clouds remains a challenge due to the resources and time required for data processing and dataset construction. The large volume of 3D point clouds leads to excessive computational costs, storage demands, and time consumption during dataset construction and training. Therefore, it is necessary to appropriately reduce the dataset size for efficient utilization while ensuring object detection performance. This necessitates a study on dataset downsampling strategies that maintain optimal density and detection accuracy. In this study, an experimental dataset similar to the S3DIS (Stanford Large-Scale 3D Indoor Spaces) dataset was constructed. The density of the 3D point clouds was adjusted in five levels by reducing points per unit area by 20% increments. These datasets were applied to a deep learning architecture to analyze object detection accuracy. Subsequently, the findings were applied to a shipyard dataset to streamline large volume point clouds and evaluate detection performance, thereby assessing their practical applicability. The results demonstrated that reducing the experimental dataset density to approximately 20% still maintained object detection accuracy of around 95% IoU for key objects. This indicates that lightweight datasets can reduce processing resources and costs while preserving detection performance. Additionally, applying the approach to real shipyard datasets revealed that object detection was feasible with reduced data (approximately 4.6% of the raw data). This study provides a practical framework for constructing efficient deep learning models for object detection by downsampling datasets in large-scale industrial environments like shipyards. It is expected to contribute to the establishment of automated data management systems for production management and process efficiency enhancement. Further analysis is required to evaluate performance at extreme low densities (below 20%). Moreover, while this study employed simple downsampling techniques, future work should explore the performance of various downsampling methods to optimize detection accuracy.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100648"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new welding distortion analysis method considering inherent deformation-based tendon force estimation","authors":"Hyun-Duk Seo ,&nbsp;Jae Min Lee","doi":"10.1016/j.ijnaoe.2024.100640","DOIUrl":"10.1016/j.ijnaoe.2024.100640","url":null,"abstract":"<div><div>This paper presents a new analysis method for predicting welding distortions induced by welding heat during the assembly process in various engineering fields. In the proposed method, the tendon force contributing to longitudinal bending deformation is calculated based on the measured inherent deformations in the welding specimen. Additionally, welding distortions along the transverse and longitudinal directions are simultaneously estimated without undesired numerical errors by adopting orthotropic thermal coefficients. Through the proposed method, reliable numerical solutions can be obtained using only linear elastic analysis with the finite element procedure. Consequently, the proposed method can be easily applied to multi-pass welding problems without requiring additional treatments, as it relies on the inherent deformations for the analysis. The performance of the proposed method is verified through numerical and experimental investigations for fillet-welded structures.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100640"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A route planning method for small ships in coastal areas based on quadtree","authors":"Dong-Guen Jeong ,&nbsp;Myung-Il Roh ,&nbsp;In-Chang Yeo ,&nbsp;Ki-Su Kim ,&nbsp;Jun-Sik Lee","doi":"10.1016/j.ijnaoe.2025.100647","DOIUrl":"10.1016/j.ijnaoe.2025.100647","url":null,"abstract":"<div><div>Route planning for large commercial ships generally revolves around economic factors, such as fuel consumption and travel distance, which are often influenced by maritime weather conditions. In contrast, small ships navigating coastal areas, such as yachts, prioritize safety and navigational convenience. Although extensive research has been conducted on route planning for commercial ships, more studies focusing on small ships are required. This study introduces a novel route planning method for coastal areas tailored to small ships. The proposed method begins by generating quadtree charts derived from an S-57 chart. Considering the lower computational performance typically observed for small ships, a quadtree chart offers a more efficient solution than a traditional regular grid. This structure allows for high-resolution representation only where necessary, considering water depth and coastal obstacles to ensure safe navigation. The route planning process comprises two layers: high-level and low-level. The high-level layer uses lower-resolution charts to outline a general route between the departure and arrival points and to identify key entrances along the way. The low-level layer, which employs higher-resolution charts, generates a detailed route from the departure point to the entrance and from the entrance to the arrival point. The final step involves smoothing to ensure a seamless and navigationally efficient route. Adopting a hierarchical approach can significantly enhance the efficiency of route planning by utilizing a multi-level structure, thereby reducing the time required for route planning. This methodology enables more effective responses in continuous maritime environments, ensuring high efficiency even during real-time route updates and modifications. The proposed method was applied to the coastal areas of the Republic of Korea to assess its effectiveness. In this study, the proposed method was compared with conventional chart generation methods. The results demonstrate that the method provides suitable and safe route planning for small ships, offering a reliable approach for coastal area navigation.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"17 ","pages":"Article 100647"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}