Applied Ocean Research最新文献

{"title":"Generation of navigation database using AIS data for remote situational awareness of coastal vessels","authors":"Chaewon Kim ,&nbsp;Seonghun Hong ,&nbsp;Jeonghong Park ,&nbsp;Jinwoo Choi ,&nbsp;Hye-Jin Kim","doi":"10.1016/j.apor.2024.104401","DOIUrl":"10.1016/j.apor.2024.104401","url":null,"abstract":"<div><div>Automatic identification system (AIS) data obtained from vessel traffic service (VTS) centers can be used for maritime traffic analysis and management as they include various useful information pertaining to each vessel navigated in the control area of VTS centers. This study presents a systematic procedure to generate a database (DB) using historical AIS data for learning the navigation patterns of coastal vessels and applying them to remote situational awareness. A hierarchical navigation DB structure is designed to simultaneously include the positional and kinematic attributes of AIS data classified based on vessel type and length class. Statistical parameterizations are performed to efficiently represent the positional and kinematic attributes in the DB space. Experimental results based on an actual AIS dataset obtained from a VTS center are presented to demonstrate the feasibility and usefulness of the proposed method for remote situational awareness.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104401"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Wave feedforward control for dynamic positioning vessel under swell-dominated floatover condition: A numerical and experimental study","authors":"Boyue Wang,&nbsp;Xiaoxian Guo,&nbsp;Xin Li","doi":"10.1016/j.apor.2024.104396","DOIUrl":"10.1016/j.apor.2024.104396","url":null,"abstract":"<div><div>Dynamic positioning (DP) floatover has become a widely adopted method for installing the topsides of offshore structures due to its cost-effectiveness and precise positioning capabilities. In swell-dominated seas, the thrusters of a DP vessel generate periodic forces that can lead to wear and tear on the actuators and potentially result in thruster failure during floatover operations. The usage of thrusters is a limiting factor in such conditions. This paper introduced a novel method to mitigate reciprocating forces using wave height prediction and feedforward control during floatover operations. A Kalman observer was employed to reconstruct the wave field in real-time based on wave height measurements obtained from the four legs of the jacket, which enabled the estimation of wave height at the center of the vessel and the prediction of swell frequency motion. By employing gain scheduling, the resistance from DP thrust was minimized. Numerical simulations and model-scale experiments demonstrated the effectiveness and adaptability of the proposed feedforward algorithm compared to two basic motion observers. The proposed methods significantly reduced the periodic thrust on the DP vessel, thereby overcoming the limitations of floatover operations in swell-dominated sea states.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104396"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Optimization design of nozzle parameters under the condition of submerged water jet breaking soil based on response surface method","authors":"Yueqin Qiu ,&nbsp;Xiongdong Lan ,&nbsp;Jian Liu ,&nbsp;Guanshi Wang ,&nbsp;Zhenhua Huang","doi":"10.1016/j.apor.2024.104369","DOIUrl":"10.1016/j.apor.2024.104369","url":null,"abstract":"<div><div>This study examines the impact of nozzle structural parameters on soil-breaking depth and width. Utilizing the Arbitrary Lagrange-Euler (ALE) algorithm, a finite element model for submerged water jet soil-breaking was established and validated through laboratory experiments. Response surface methodology was employed to optimize nozzle parameters, analyzing the effects of cone angle, diameter, and length on soil-breaking outcomes. Findings indicate that nozzle diameter exerts the most significant influence on both depth and width, while the interaction between diameter and cone angle has the most pronounced effect. By integrating a satisfaction function and using soil-breaking depth and width as evaluation metrics, the nozzle design was optimized. The optimal parameters identified for the conical nozzle are a cone angle of 12.21°, a diameter of 1.16 mm, and a length of 2 mm, achieving an optimal balance between depth and width.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104369"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Deep-sea soft soil and deep-sea mining vehicle interaction: From soil properties to locomotion performance","authors":"Ning Zhang ,&nbsp;Weikun Zhai ,&nbsp;Shiyang Yin ,&nbsp;Xuguang Chen ,&nbsp;Jianxin Xia ,&nbsp;Lubao Luan ,&nbsp;Aoshuang Zhai","doi":"10.1016/j.apor.2024.104372","DOIUrl":"10.1016/j.apor.2024.104372","url":null,"abstract":"<div><div>The vast ocean floor holds abundant mineral resources, characterised by a wide variety, large reserves, and high grade. It has tremendous prospects for development and utilisation. Necessitating intensified efforts in key core technology development for deep-sea mineral resource exploitation. As crucial equipment in the field of deep-sea mining engineering, the performance and reliability of heavy-duty equipment for deep-sea mining play a critical role in the development of deep-sea resources. This paper provides a systematic analysis of the development status of deep-sea mining vehicles both domestically and internationally. Starting from the fundamental scientific issues of soil-vehicle interactions, it reviews the progress of research on the mechanical characteristics of deep-sea soft soil, stress response mechanisms under mining vehicle loading, and the behavior of track-soft soil interface contact. The evolution of the walking performance and motion behavior of deep-sea mining vehicles is summarized, and existing issues and future research priorities related to the coupling effect between deep-sea soft soil and dynamic equipment are identified.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104372"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Model propulsion tests in head and following waves of a bulk carrier","authors":"Sverre Steen ,&nbsp;Adrian Portillo-Juan ,&nbsp;Simone Saettone","doi":"10.1016/j.apor.2024.104405","DOIUrl":"10.1016/j.apor.2024.104405","url":null,"abstract":"<div><div>The results of self-propulsion measurements in calm water and regular head and following waves, under different propeller loading conditions, are presented. The experimental measurements were performed in the large towing tank at the Marine Technology Centre in Trondheim. The model was a 1:32 scale replica of a 200-meter bulk carrier, equipped with a 4-bladed, moderately skewed propeller measuring 210.9 mm in diameter. Results for wave-added resistance and thrust, propulsive coefficients, ship motion RAOs (Response Amplitude Operators), effective wake fraction, advance ratio magnitudes and amplitudes, and efficiencies (<span><math><mrow><msub><mrow><mi>η</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>,</mo><msub><mrow><mi>η</mi></mrow><mrow><mi>H</mi></mrow></msub><mo>,</mo><mspace></mspace><msub><mrow><mi>η</mi></mrow><mrow><mi>R</mi></mrow></msub></mrow></math></span> and <span><math><msub><mrow><mi>η</mi></mrow><mrow><mi>D</mi></mrow></msub></math></span>) were computed. Firstly, resonance at a wave length to ship length ratio of 1.2 in head waves was generally observed in all results. Particularly in head waves, this lead to a significant increase in the wave added resistance. The thrust deduction fraction <span><math><mi>t</mi></math></span> was higher in waves than in calm water, but the variation in the different wave conditions was small and difficult to see a systematic trend, so a constant thrust deduction fraction in waves were assumed in the analysis. Due to the differences observed between the thrust deduction factor in calm water and in waves, the added thrust coefficient presented higher values than wave added resistance coefficient. The increased resistance in head waves of wave length to ship length ratio of 1 and longer lead to an increase in propeller loading, leading to larger thrust coefficient <span><math><msub><mrow><mi>K</mi></mrow><mrow><mi>T</mi></mrow></msub></math></span>, lower advance number <span><math><mi>J</mi></math></span> and lower propeller efficiency <span><math><msub><mrow><mi>η</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>. The effective wake fraction showed a slight reduction in head waves and a slight increase in following waves. In following waves, the added thrust was small, leading to small changes in the average values of the propulsive coefficients. However, the amplitudes of thrust, torque and advance number were significantly larger in following waves than in head waves, something that might be of importance for propeller shaft and engine dynamics. Regarding ship motions, overall, lower ship speeds produced larger motions. Also, in following waves, a consistent increase in motion (heave, surge, and pitch) was observed with increasing wavelength.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104405"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Optimizing time-delay estimation for underwater acoustic positioning in tank inspection robots to mitigate reflection interference","authors":"Zhenyu Xu,&nbsp;Zhangwei Chen","doi":"10.1016/j.apor.2025.104427","DOIUrl":"10.1016/j.apor.2025.104427","url":null,"abstract":"<div><div>Robot inspection of large storage tanks has become the primary method for addressing hidden risks in the petrochemical industry. Accurate positioning of Tank Inspection Robots (TIR) is crucial in this process. However, the unique characteristics of the liquid medium and tank walls introduce challenges such as noise, reverberations, and multipath effects, which frequently complicate the acoustic positioning of robots. These issues are further complicated by numerous interface reflections. To address the problems caused by reflections, this paper focuses on time-delay estimation for underwater acoustic positioning. It analyzes the impact of reflections on various acoustic positioning methods and simplifies the time-delay estimation process within the Time Difference of Arrival (TDOA) localization algorithm in reverberant environments. To this end, the paper introduces the AMCOCEP algorithm, which integrates Generalized Cross-Correlation, the cepstrum, and the Average Magnitude Difference Function (AMDF). The effectiveness of the proposed positioning model and method is validated by positioning a robot within a storage tank and comparing positioning accuracy before and after algorithm optimization. According to the experimental results, the AMCOCEP algorithm reduces the average error by 1.07 cm and improves the average accuracy by 30.7 %.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104427"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Nonlinear thermo-mechanical bending analysis of variable-thickness parallelogram plates in curved hull via a homotopy-based wavelet method","authors":"Qiang Yu ,&nbsp;Junfeng Xiao ,&nbsp;Hang Xu ,&nbsp;Zixin Wu","doi":"10.1016/j.apor.2024.104334","DOIUrl":"10.1016/j.apor.2024.104334","url":null,"abstract":"<div><div>Due to the variable-thickness parallelogram plates in ocean structure are characterized by the presence of strong moment singularity at supported obtuse corners, the wide application has turned the nonlinear mechanical analysis into one of the most important engineering concerns. In the paper, a refined geometrically nonlinear bending model of variable-thickness orthotropic parallelogram plates in curved hull under thermo-mechanical loads is proposed, while influences of linearly or quadratically thickened thickness in symmetrical or unsymmetrical profile on mechanical properties are thoroughly investigated. Three kinds of spatially thermal field in parallelogram domain are formulated on account of the coupled interaction of effects between in-plane distribution and thickness variation corresponding to the Dirichlet, Neumann and Robin thermal boundaries. A novel thickness-dependent Airy stress function is introduced overcoming the failure of traditional Airy stress function in equilibrium of in-plane forces, while the highly coupled and variable-coefficient nonlinear governing partial differential equations are firstly derived. The homotopy-based wavelet method is adopted to investigate the nonlinear thermo-elastic bending behaviors, while convergent process is verified and precision of obtained series solutions has been validated in excellent agreement with published results. The significant conclusion can be made that large-deflection nonlinear bending of such plates can be simplified with little discrepancy by omitting terms involving the derivatives of thickness variation in compatibility equation of deformation, which is generalized to the thermo-mechanical bending and greatly simplifies the analyzing procedures.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104334"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Hydrodynamic investigation of a new type of floating breakwaters integrated with porous baffles","authors":"Kang-Zhuo Hu,&nbsp;Tiao-Jian Xu,&nbsp;Sen Wang","doi":"10.1016/j.apor.2024.104380","DOIUrl":"10.1016/j.apor.2024.104380","url":null,"abstract":"<div><div>Due to their easy installation and low maintenance costs, floating breakwaters have attracted extensive attention from scholars, resulting in a series of new configurations. A novel floating breakwater integrated with porous baffles (PFB) was introduced in this research. Numerical simulations were applied to explore the interactions between the PFB and regular waves, and corresponding experiments were also completed to ensure the accuracy of the numerical results. Then, the impacts of the height, position, and porosity on the hydrodynamic performance of the PFB were analyzed through a series of numerical simulations. A comparison with conventional box-type floating breakwaters was also conducted. The results indicated that the porous baffles effectively improved the wave attenuation phenomenon and reduced the motion amplitude by weakening the wave particle velocity and concentrating the vortices near the porous baffles. Additionally, the performance of the PFB could be further increased by adjusting the baffle porosity and mounting position. The study provides valuable suggestions for the further improvement of floating breakwaters.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104380"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Optimization of the mooring system of a floating wind turbine by developing a surrogate model-assisted evolutionary framework","authors":"Ye An ,&nbsp;Zhisheng Xia ,&nbsp;Min Luo ,&nbsp;Jian Zhang ,&nbsp;Ronghua Zhu","doi":"10.1016/j.apor.2024.104373","DOIUrl":"10.1016/j.apor.2024.104373","url":null,"abstract":"<div><div>In the design and optimization of Floating Wind Turbines (FWTs), there are challenges related to the large number of design parameters and the need for efficient and accurate calculation of turbine dynamic responses. To address these issues, this study proposes a surrogate model-assisted evolutionary framework for the mooring system optimization of shallow-water wind turbines. This distinct feature of the optimization framework lies in that it employs a sparse polynomial chaos expansion surrogate model to quickly predict the performance indicator values of FWTs with different mooring configurations and adopts the differential evolution algorithm to find the mooring parameter combination with the best performance, achieving efficient, accurate, and automated multi-parameter optimization. The framework is utilized to optimize the mooring system for a FWT at a relatively shallow water depth, through defining a mooring performance evaluation indicator as the objective function that comprehensively considers mooring line tensions, platform motions, anchor tensions, and the mooring line material cost. Based on the optimization application, the accuracy of the optimization framework is verified. The dynamic responses and safety assessments of the optimized FWT in the fatigue limit state (FLS) and ultimate limit state (ULS) are conducted. The results demonstrate the effectiveness of the proposed optimization framework in enhancing a FWT's performance according to flexibly defined objective functions.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104373"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Analyses on flow structures behind submersible with flexible appendage during floating based on continuous wavelet transform and dynamic mode decomposition","authors":"Fei Yan ,&nbsp;Weiyu Kong ,&nbsp;Akira Rinoshika ,&nbsp;Bo Song ,&nbsp;Jian Zhang","doi":"10.1016/j.apor.2024.104397","DOIUrl":"10.1016/j.apor.2024.104397","url":null,"abstract":"<div><div>This study propounded a new method of installing flexible appendage on the surface of a submersible to modify the wake structure of the submersible as it floats, and explored a method of drag reduction of floating submersible. A comparative analysis of the flow structure of submersibles with varying appendage lengths was done to understand the disturbance characteristics of the wake flow structure of submersible, and the high-speed particle image velocimetry (PIV) measurement experiment was conducted at a Reynolds number of 13448. The analysis of the time-averaged and transient flow fields revealed that flexible appendage was able to break up the large-scale vortices in the wake stream as the submersible floats, but this ability diminished as the length increasing of flexible appendage. Furthermore, in order to investigate the mechanism of this phenomenon, continuous wavelet transform (CWT) and dynamic mode decomposition (DMD) were performed. The results suggested that the flexible appendage inhibited large-scale flow, and the inhibition effect decreased with increasing of flexible appendage length based on CWT. It was demonstrated that the flexible appendage was capable of reducing the energy dominance of the large-scale vortex structure, thereby facilitating the transition from large-scale to small-scale vortices based on DMD. Concurrently, it was found that the intrusion of excessively lengthy appendage into the wake region resulted in the generation of additional disturbances and impeded the process of small-scale vortex shedding.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104397"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}