International Journal of Naval Architecture and Ocean Engineering最新文献

{"title":"Natural language processing-based approach for automatically coding ship sensor data","authors":"Yunhui Kim ,&nbsp;Kwangphil Park ,&nbsp;Byeongwoo Yoo","doi":"10.1016/j.ijnaoe.2023.100581","DOIUrl":"10.1016/j.ijnaoe.2023.100581","url":null,"abstract":"<div><p>The digital transformation of ship systems requires the coding and management of large amounts of Input/Output (IO) data generated by various pieces of equipment during ship operation. In this study, we investigated a method that recognizes the text of the IO description of a ship to automatically code IO data. Accordingly, the characteristics of the IO descriptions were extracted using Term Frequency-Inverse Document Frequency (TF–IDF) and word embedding, and machine learning techniques such as K-Nearest Neighbors (KNN) and Support Vector Machine (SVM) and deep learning models such as Long Short-Term Memory (LSTM), Gated Recurrent Unit (GRU), and bidirectional LSTM (BiLSTM) were used to classify them into codes. Through the application of different text preprocessing techniques based on the unique characteristics of the data, the performances of the algorithms improved; the experimental results showed an accuracy of up to 91%, with an average improvement in accuracy of 5% for each algorithm.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100581"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678223000705/pdfft?md5=19967ff524563e07cf23a08952bac53a&pid=1-s2.0-S2092678223000705-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139071206","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":"Linear diffraction and radiation theory of water waves by a truncated vertical circular cylinder with heave plate in deep and shallow drafts","authors":"Seung-Yoon Han,&nbsp;Benjamin Bouscasse,&nbsp;Vincent Leroy,&nbsp;David Le Touzé","doi":"10.1016/j.ijnaoe.2023.100580","DOIUrl":"10.1016/j.ijnaoe.2023.100580","url":null,"abstract":"<div><p>A first-order analytical theory on a truncated and surface-piercing vertical circular cylinder with a circular plate mounted at the bottom of the cylinder was generalized to solve the linear wave diffraction and radiation problems based on potential flow and the hypothesis of small wave and motion amplitudes. The domain was decomposed, and the linearized velocity potentials were derived in each subdomain and matched on each subdomain interface employing pressure and normal velocity continuity. The linear hydrodynamic loads obtained with the analytical method were compared with the results of linear boundary element method (BEM) solvers. Dedicated experimental campaigns were performed on fixed models with regular waves (diffraction) and then on models oscillating in surge, heave, and pitch motions without incident waves (radiation). The analytical method describes well the wave excitation loads from the experiments for small wave steepness (<span><math><mi>H</mi><mo>/</mo><mi>λ</mi><mo>=</mo><mn>0.02</mn></math></span>). The predictions of added mass and damping are shown to be applicable to the surge motion, only for small Keulegan-Carpenter numbers (<span><math><mi>K</mi><mi>C</mi><mo>&lt;</mo><mn>1</mn></math></span>). On the other hand, the analytically predicted radiated waves demonstrate satisfactory agreement with experiments for all motions.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100580"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678223000699/pdfft?md5=d05bb84ca60f23d0f906b43371c66e8b&pid=1-s2.0-S2092678223000699-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139082991","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":"Performance analysis of passive heave compensator operated with inclined piston using analytical method","authors":"Namkug Ku","doi":"10.1016/j.ijnaoe.2024.100624","DOIUrl":"10.1016/j.ijnaoe.2024.100624","url":null,"abstract":"<div><div>When performing operations such as drilling in the ocean, floating platforms undergo vertical motion due to waves, which negatively impacts these operations. So passive heave compensator(PHC) is used to counteract it. In many studies, the analysis of PHC with pneumatic springs has been done. Some of these papers analyzed it using simple second-order differential equations, but there was no case of modeling considering the pneumatic spring installed tilted in the PHC. On the other hand, in some papers, the characteristics were analyzed by numerical methods using multi-body dynamics equations, and it is time consuming. Therefore, in this paper, a second-order ordinary differential equation modeling method for PHC with an inclined pneumatic spring was presented and verified by comparison with the numerical method. Using the model presented in this paper, it is possible to analyze as accurate as conventional analytical methods, and to analyze characteristics faster than numerical methods.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100624"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698380","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":"Corrosion area detection and depth prediction using machine learning","authors":"Eun-Young Son,&nbsp;Dayeon Jeong,&nbsp;Min-Jae Oh","doi":"10.1016/j.ijnaoe.2024.100617","DOIUrl":"10.1016/j.ijnaoe.2024.100617","url":null,"abstract":"<div><p>Corrosion reduces the thickness of a structure, making it less safe and reducing its lifespan. In particular, ships are vulnerable to corrosion because they are always submerged in seawater. This corrosion is identified through regular inspections of the ship structure, and gradually increases in scope if no action is taken at an early stage. In this study, we developed a model to detect the corrosion areas and predict the depth of corrosion in the detected areas. The corrosion area detection model used a machine learning model based on Mask R-CNN. The 35,753 images were used to map corrosion images and measured corrosion depths. Four different color maps and regression algorithm were used to predict corrosion depths and their performance was compared. The new attempt to predict the corrosion depth from images in this study will contribute to improving existing corrosion control methods by providing information for corrosion prevention and maintenance.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100617"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000360/pdfft?md5=ff4d3a1dda19bf30e9c6c74e53b12ef6&pid=1-s2.0-S2092678224000360-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270570","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 method for implementing a ship navigation simulator for the generation and utilization of virtual data","authors":"Min-Chul Kong ,&nbsp;Myung-Il Roh","doi":"10.1016/j.ijnaoe.2024.100604","DOIUrl":"10.1016/j.ijnaoe.2024.100604","url":null,"abstract":"<div><p>Active research is underway to utilize various sensors for situational awareness, but validating these studies requires real sensor data, which is challenging to acquire due to the time and space constraints inherent in ships. Additionally, the diverse formats of sensor data and the need for postprocessing pose further hurdles. By developing a ship navigation simulator that faithfully replicates real-world environments, these limitations can be overcome, and ample virtual sensor data can be generated through immersive simulations. In this study, we propose a method for implementing such a simulator. A life-sized terrain model was placed within a virtual reality environment, representing maritime environments, including port structures. To simulate ship motions according to maritime weather conditions, we applied various laws of physics within virtual reality. Finally, to provide validation data for critical navigation technologies, such as collision avoidance and ship detection, we generated a virtual automatic identification system and camera data. We implemented and operated a ship navigation simulator using this approach, and simulations conducted across various environments generated real-time sensor data efficiently, affirming the effectiveness of the proposed method.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100604"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000232/pdfft?md5=3c76be6efcc1fef5d693a9d05a8fe0e6&pid=1-s2.0-S2092678224000232-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575982","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":"An experimental study on the motion-structure coupled characteristics of multi-linked floating unit offshore structure with two different connection conditions","authors":"Kangsu Lee ,&nbsp;Kichan Sim","doi":"10.1016/j.ijnaoe.2024.100614","DOIUrl":"10.1016/j.ijnaoe.2024.100614","url":null,"abstract":"<div><p>With the recent intensification of climate change due to global warming, the importance of renewable energy has been highlighted, emphasizing the need for renewable energy development. In the case of renewable energy power generation, it is installed and operated on a large scale to meet energy demand, economic efficiency, and optimize local resources. Therefore, the number of cases of installation on water and sea with high space utilization is gradually increasing. When operating large-scale power systems, conservative design and review are necessary because damage to the structures can cause cascading failures, leading to major accidents. In particular, for photovoltaic systems, the method of expansion by connecting individual unit structures is commonly used. Therefore, it is necessary to analyze the characteristics of the unit structures and the connection methods. In this study, a fluid-structure coupled analysis was performed on the unit structures of a multi-linked floating offshore structures, which can be large-scale expansion, developed by the Korea Research Institute of Ships and Ocean Engineering. The characteristics were analyzed based on the connection method. The analysis results showed that when the connection method was a hinged condition, the pitch motion increased compared to the fixed condition, but since the peak occurred at a high frequency with a 4-s period, it is advantageous to avoid resonance. In particular, it was confirmed that the maximum stress was reduced by approximately three times, which is beneficial for structural integrity. Additionally, it was found that as the stress distribution moved from the center to the edges, it is also advantageous in terms of maintenance. In addition, the numerical method of the multi-linked floating offshore structures and the characteristics of hinged condition were verified through model tests.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100614"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000335/pdfft?md5=ebf34e2805fbb616f6f32c57256394b9&pid=1-s2.0-S2092678224000335-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169085","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":"Research on safety evaluation and weather routing optimization of ship based on roll dynamics and improved A* algorithm","authors":"Zilong Guo ,&nbsp;Mei Hong ,&nbsp;Yongchui Zhang ,&nbsp;Jian Shi ,&nbsp;Longxia Qian ,&nbsp;Hanlin Li","doi":"10.1016/j.ijnaoe.2024.100605","DOIUrl":"10.1016/j.ijnaoe.2024.100605","url":null,"abstract":"<div><p>With the steady growth of international trade, sea transport has become indispensable, leading to an increase in maritime accidents. The sinking of the Russian Black Sea Fleet flagship, the guided missile cruiser “Moskva,” underscores the critical need for enhanced maritime safety. However, the dynamics of ship stability, particularly under transverse wind and wave conditions, remain unclear. We aimed to explore ship navigation safety by using the Moskva incident as a case study. Specifically, our objective was to investigate the influence of wind and waves on ship stability, calculate the capsizing probability of the vessel, and devise a fast and safe return path to port. We conducted a comprehensive review of existing literature on ship stability and path-planning algorithms. Leveraging this knowledge, we established the dynamics equation under transverse wind and wave conditions and integrated risk and vulnerability indicators to obtain a quantitative sea-area risk zoning map. Additionally, we employed the A* algorithm to plan a path under International Maritime Organization rules restrictions. Our findings reveal insights into ship stability dynamics and the importance of considering environmental factors in navigation safety. We calculated the capsizing probability of Moskva and devised a fast and safe return path to port, highlighting the practical application of our methodology. This study contributes to the understanding of ship navigation safety by addressing the knowledge gap in ship stability dynamics. Our findings underscore the significance of considering environmental factors in navigation safety planning. However, limitations exist in terms of data availability and model accuracy. Future research should explore additional factors impacting ship stability and refine path-planning algorithms for enhanced safety.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100605"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000244/pdfft?md5=78f50c14be213481c96bc258f4167cd8&pid=1-s2.0-S2092678224000244-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141638897","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 suggestion for space harmonic injection into motor current to reduce propeller vibration","authors":"Yeojin Hyun ,&nbsp;Kwang-Jun Paik ,&nbsp;Soyoung Sung ,&nbsp;Junghyung Park ,&nbsp;Soon-Hyun Lee ,&nbsp;Jinyeong Park","doi":"10.1016/j.ijnaoe.2024.100618","DOIUrl":"10.1016/j.ijnaoe.2024.100618","url":null,"abstract":"<div><p>Propellers produce fluctuating thrust and torque as they rotate in a non-uniform wake field. They contribute most of the vibration and noise generated by the propeller and can lead to mechanical damage to shafts and bearings. Recently, the demand for electric propulsion ships has increased. As the torque and speed fluctuations are generated in marine propellers, harmonic components in the current and voltage of the propulsion motor occur and lead to increased losses, device degradation, and torque pulsations. In this study, a harmonic injection method is proposed to reduce the impact of motor and mechanical vibration caused by the fluctuating load torque of the propeller. A harmonic component is applied to the current of the motor to generate a motor torque with a different phase of the same magnitude as the variation of the load torque of the motor. In this study, a computational fluid dynamics simulation was performed to obtain the torque of the target vessel, medium range tanker, and a MATLAB Simulink was used to model the motor simulation. It was found that the harmonic injection method can reduce the mechanical torque fluctuation of the motor by 87%.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100618"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000372/pdfft?md5=8883af03488bec0afe7af9e326a46906&pid=1-s2.0-S2092678224000372-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142239941","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 numerical study on the optimization of the slit shape of a jet injection propeller","authors":"Jun-Hee Lee ,&nbsp;Ju-Han Lee ,&nbsp;Myeong-Min Kim ,&nbsp;Dohan Oh ,&nbsp;Kwang-Jun Paik","doi":"10.1016/j.ijnaoe.2023.100578","DOIUrl":"10.1016/j.ijnaoe.2023.100578","url":null,"abstract":"<div><p>The shape of the slit that injects the jet from the surface of the propeller was optimized through numerical computations. The high-pressure drop on the propeller surface caused by jet injection could be improved by modifying the hydrofoil geometry of the propeller. As the cover length increased and the slit was located at the center of the propeller, the volume of jets leading to the trailing edge increased, and the propulsion performance was improved. As the height of the slit increased, the thrust increased due to the Coanda effect, and the torque decreased because of the thrust of the jet. The jet injection pattern differed according to the area of the slit and tunnel, which caused a difference in the propeller performance. The jet pattern changed according to the area of the slit and tunnel, leading to a change in propeller performance. It was effective in improving the efficiency by injecting from as wide an area as possible, and the efficiency was improved by approximately 2 % considering the pump efficiency through optimization of the slit shape.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100578"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678223000675/pdfft?md5=8318a7286ca15e40bdb33e1870d13c8f&pid=1-s2.0-S2092678223000675-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139029045","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":"Direct prismatic coefficient variation to hull form surface","authors":"Dayeon Jeong,&nbsp;Min-Jae Oh","doi":"10.1016/j.ijnaoe.2024.100615","DOIUrl":"10.1016/j.ijnaoe.2024.100615","url":null,"abstract":"<div><div>The initial ship design process aims to optimize the hull form to enhance ship efficiency. During this phase, hull form variations are executed based on a reference ship to meet shipowner requirements, such as altering the <span><math><mrow><msub><mi>C</mi><mi>P</mi></msub></mrow></math></span> (prismatic coefficient) to adjust the section lines. Once these variations are made, a surface is generated. However, this iterative process can be time-consuming as the surface creation must be done manually each time. Thus, we propose a method to directly apply <span><math><mrow><msub><mi>C</mi><mi>P</mi></msub></mrow></math></span> variation onto the hull form surface, setting the variated section line as a constraint. In this study, the proposed method is employed to modify the hull form surface to meet <span><math><mrow><msub><mi>C</mi><mi>P</mi></msub></mrow></math></span> requirements. The section lines of the modified surface are then extracted to validate the results. This streamlines in the initial hull form design, reduces the overall design time, and yields high-quality hull form surfaces efficiently.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100615"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356782","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}