Ocean Engineering最新文献_第7页

Experimental investigation of hydrodynamic characteristics of deep-sea mining riser subjected to vortex-induced vibration 深海采矿隔水管涡激振动水动力特性试验研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-27 DOI: 10.1016/j.oceaneng.2026.124421

Yu Liu , Shuqing Wang , Junfeng Du , Yufeng Jiang

This study explored the hydrodynamic load distribution characteristics of vortex-induced vibration (VIV) of a mining riser under uniform flow through model testing. A novel inverse identification approach based on discrete strain responses was proposed to determine hydrodynamic loads. The Euler-Bernoulli beam differential equation was modified to incorporate dynamic spatiotemporal tension, and a structural response control equation considering variable and temporal tension and nonlinear effects was established. Using this framework, an inverse solution enables accurate identification of hydrodynamic loads on mining risers. The hydrodynamic load of the overhanging mining riser was realized by inverse solution based on the structural response control equation. Vortex-excited load coefficients were obtained via a least squares method. The results indicate that, compared with conventional oil and gas risers, VIV generates a non-uniform, periodic load in mining risers. VIV amplifies the mean drag, with the mean drag coefficient ranging from 1.60 to 1.80, 1.30 to 1.50 times that of conventional rigid risers in the subcritical Reynolds number regime. Cross-flow (CF) vortex loads exhibit approximate symmetry about the riser midpoint, whereas in-line (IL) loads are distinctly asymmetric, contrasting with the symmetric distribution of vortex loads observed in strongly constrained oil and gas risers. These findings provide critical data reference for validating Computational Fluid Dynamics (CFD) simulations of riser hydrodynamics.

通过模型试验，探讨了均匀流动条件下矿山立管涡激振动的水动力载荷分布特性。提出了一种基于离散应变响应的水动力载荷反辨识方法。将欧拉-伯努利梁微分方程修正为考虑动态时空张力，建立了考虑变时张力和非线性效应的结构响应控制方程。利用这个框架，一个逆解能够准确地识别采矿立管上的水动力载荷。采用基于结构响应控制方程的反解方法，实现了悬挑立管的水动力载荷。通过最小二乘法得到涡激载荷系数。研究结果表明，与常规油气立管相比，涡激振动在采矿立管中产生非均匀的周期性载荷。在亚临界雷诺数范围内，涡激隔水管的平均阻力系数为常规刚性隔水管的1.60 ~ 1.80倍，是常规刚性隔水管的1.30 ~ 1.50倍。横流（CF）涡旋载荷在隔水管中点表现出近似的对称性，而直线（IL）涡旋载荷则明显不对称，这与强约束油气隔水管中观察到的涡旋载荷的对称分布形成了鲜明对比。这些发现为验证立管流体动力学的计算流体动力学（CFD）模拟提供了重要的数据参考。

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引用次数: 0

A data-driven comparative risk assessment of marine traffic accidents using an object-oriented Bayesian network 基于面向对象贝叶斯网络的海上交通事故数据驱动比较风险评估

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.oceaneng.2026.124372

Xue Yang , Zhiying Lin , Wenjun Zhang , Sheng Xu , Shenping Hu

Arctic shipping is expanding as sea ice retreats, yet navigation remains exposed to rapidly changing ice regimes, severe weather, and limited shore-support infrastructure. This study develops an object-oriented Bayesian network (OOBN) to support a comparative, accident-type-specific risk assessment of collisions, groundings, and machinery damages. Risk factors were compiled through a structured literature review and coded from 49 official accident investigation reports; 196 normal transit records were introduced as non-accident data to mitigate sampling bias. In the OOBN, accident causation is organised into human, technical, organisational and environmental domains, and the resulting sub-networks allow sensitivity-based ranking of influential factors. Because the transit (non-accident) records do not explicitly describe MTO states, we repeated the ranking under two bounding treatments for unobserved MTO variables (assigned 0.5 versus set to 0). Model outputs differ by accident type, indicating distinct risk signatures; they also suggest interaction-driven amplification in which environmental stressors narrow operational margins and then couple with degraded human performance and technical condition. Overall, the framework links coded accident evidence to a ranked list of intervention targets, which can inform maintenance planning, polar training programmes and regulatory oversight.

随着海冰的消退，北极航运正在扩张，但航行仍然面临着快速变化的冰况、恶劣天气和有限的海岸支持基础设施。本研究开发了一个面向对象的贝叶斯网络（OOBN），以支持碰撞、接地和机械损坏的比较、事故类型特定的风险评估。风险因素通过结构化文献综述汇编，并从49份官方事故调查报告中编码；196个正常过境记录作为非事故数据被引入以减轻抽样偏差。在OOBN中，事故原因被组织为人为、技术、组织和环境领域，由此产生的子网络允许对影响因素进行基于敏感性的排名。由于运输（非事故）记录没有明确描述MTO状态，因此我们在未观察到的MTO变量的两个边界处理下重复排序（赋值为0.5，而设置为0）。不同事故类型的模型输出不同，表明不同的风险特征；他们还提出了相互作用驱动的放大，其中环境压力因素缩小了操作边际，然后与人类表现和技术条件的下降相结合。总体而言，该框架将编码的事故证据与干预目标的排名清单联系起来，这可以为维护计划、极地培训计划和监管监督提供信息。

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引用次数: 0

Strength and deformation characteristics of coral sand accounting for particle breakage 考虑颗粒破碎的珊瑚砂强度和变形特性

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.oceaneng.2026.124309

Yadong Chen , Xu Liu , Yang Tang , Haifeng Zhang , Huasheng Sun , Hongbing Yang

To investigate the evolution and intrinsic mechanism of the particle-breakage-related shear behavior of coral sand under varying gradation and density conditions, a series of direct shear tests were systematically designed. Based on the analysis of the experimental results, empirical equations were established for effectively simulating the breakage behaviour and strength characteristics. The results demonstrate that the stress-strain behavior of coral sand transitions from softening to hardening response with increasing vertical normal stress levels, and the shear strength in accordance with the Mohr-Coulomb failure criterion. Notably, the internal friction angle and apparent cohesion exhibit a dynamic complementary relationship. For well-graded coral sand, the internal friction angle shows a bimodal distribution as the relative density increases, whereas poorly-graded sand reveals a unimodal distribution. Dilatancy decreases as stress rises, which is typically observed; however, its variation with density differs from that of conventional quartz sand, as it does not increase monotonically. Particle breakage intensifies linearly with stress, resulting in the depletion of coarse particles, an accumulation of fine particles, and a dynamic equilibrium within intermediate particle groups. The developed empirical equations adeptly incorporate the influences of density and confining pressure on relative breakage rate, showing strong concordance with experimental data while effectively capturing the bimodal distribution of friction angles and the complementary bimodal valley-shaped distribution of apparent cohesion.

为了研究不同级配和密度条件下珊瑚砂颗粒破碎相关剪切行为的演化及其内在机制，系统设计了一系列直剪试验。在对试验结果进行分析的基础上，建立了能有效模拟其破坏行为和强度特性的经验方程。结果表明：珊瑚砂的应力-应变行为随竖向法向应力水平的增加由软化向硬化转变，抗剪强度符合Mohr-Coulomb破坏准则；内摩擦角与表观黏聚力呈动态互补关系。分级较好的珊瑚砂内摩擦角随相对密度的增加呈双峰分布，分级较差的珊瑚砂内摩擦角呈单峰分布。剪胀率随应力升高而减小，这是典型的观察结果；但其随密度的变化与常规石英砂不同，不是单调递增的。颗粒破碎随应力线性增强，导致粗颗粒耗竭，细颗粒积聚，中间颗粒群内达到动态平衡。所建立的经验方程熟练地考虑了密度和围压对相对破碎率的影响，与实验数据具有较强的一致性，同时有效地捕捉了摩擦角的双峰分布和表观黏聚力的互补双峰谷形分布。

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引用次数: 0

A hybrid fault diagnosis framework for rudder propellers: Physics-guided learning from data and simulation 方向舵螺旋桨混合故障诊断框架：基于数据和仿真的物理指导学习

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.oceaneng.2026.124419

Ennan Gao , Yang Ming , Kaiwen Zhao , Yongdong Shu , Feiyun Xu

Rudder propellers, as fully azimuthing thrusters, integrate propulsion and steering functions, playing a vital role in marine vessel performance and safety. However, their large size and complex installation limit the acquisition of fault data through physical experiments, posing challenges for intelligent fault diagnosis. To address this, a hybrid fault diagnosis framework is proposed, driven by both measured data and simulation models. A high-fidelity multibody dynamics model is developed with boundary conditions calibrated via CFD, enabling the generation of fault-labeled synthetic vibration signals. A dual-branch generative adversarial network (GAN), incorporating both time-domain and time–frequency features, is used to adapt simulated signals to real-world measurement conditions. The generated samples achieve high fidelity, with frequency-domain cosine similarity exceeding 0.88. A physics-informed neural network (PINN) with a matching dual-branch structure is then constructed for fault classification. Experimental results on a rudder propeller test platform show that the proposed method achieves up to 100 % classification accuracy. Compared to existing diagnostic approaches, this framework offers superior accuracy and robustness by effectively integrating physical modeling, adversarial domain adaptation, and physics-guided learning.

舵螺旋桨作为全方位推进器，集推进和转向功能于一体，对船舶的性能和安全起着至关重要的作用。然而，它们体积大、安装复杂，限制了物理实验获取故障数据，给智能故障诊断带来了挑战。为了解决这一问题，提出了一种由实测数据和仿真模型驱动的混合故障诊断框架。通过CFD标定边界条件，建立了高保真多体动力学模型，实现了故障标记合成振动信号的生成。采用双分支生成对抗网络（GAN），结合时域和时频特征，使模拟信号适应现实世界的测量条件。生成的样本保真度高，频域余弦相似度超过0.88。然后构造一个具有匹配双分支结构的物理信息神经网络（PINN）进行故障分类。在一个舵螺旋桨测试平台上的实验结果表明，该方法的分类准确率可达100%。与现有的诊断方法相比，该框架通过有效地集成物理建模、对抗域适应和物理引导学习，提供了更高的准确性和鲁棒性。

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引用次数: 0

Seismic centrifuge modelling of repowered offshore wind turbine considering monopile foundation strengthening and superstructure replacement 考虑单桩基础加固和上部结构更换的再动力海上风力机地震离心模型

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-25 DOI: 10.1016/j.oceaneng.2026.124432

Xiaojing Jia , Fayun Liang , Hao Zhang , Yifeng Lin , Zhouchi Yuan

Numerous offshore wind turbines (OWTs) are now approaching end-of-life (EoL). As an economical and sustainable strategy, repowering is commonly used for EoL scenarios. However, there is limited research on the service performance of repowered OWTs during their extended life, particularly concerning the seismic performance. In this study, a series of centrifuge shaking table tests was conducted to investigate the dynamic characteristics and seismic responses of the repowered monopile-supported OWT. Specifically, the original 2 MW turbine superstructure was upgraded with corresponding 3 MW components while retaining the serviceable foundation. Before repowering, solidified soil remediation was employed to enhance foundation performance in response to scour, a common phenomenon around marine foundations caused by currents. The results show that replacing the superstructure (upgraded to 3 MW turbine) reduces the natural frequencies of the OWT. Additionally, structural accelerations and displacements are changed under different earthquakes, while peak rotation and bending moments of the foundation at the mudline are amplified. These findings indicate potential risks of structural resonance and excessive deformation in repowered wind turbines. It is necessary to reassess modal characteristics and seismic performance during their extended service life to ensure the reliability of upgrade and maximize the long-term benefits of OWTs.

许多海上风力涡轮机（owt）正接近使用寿命（EoL）。作为一种经济且可持续的策略，重新供电通常用于EoL场景。然而，对于换能器在延长使用寿命期间的使用性能，特别是抗震性能方面的研究非常有限。本文通过一系列的离心振动台试验，研究了再供电单桩支撑OWT的动力特性和地震反应。具体而言，原有的2兆瓦涡轮机上部结构升级为相应的3兆瓦组件，同时保留了可使用的基础。在重新供电之前，采用固化土壤修复来提高地基性能，以应对冲刷，这是海流引起的海洋地基的常见现象。结果表明，更换上部结构（升级为3mw涡轮机）降低了OWT的固有频率。此外，不同地震作用下结构的加速度和位移会发生变化，而泥线处基础的峰值转动弯矩和弯矩被放大。这些发现表明，再动力风力涡轮机存在结构共振和过度变形的潜在风险。在延长使用寿命期间，有必要对其模态特性和抗震性能进行重新评估，以确保其升级的可靠性，并使其长期效益最大化。

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引用次数: 0

Experimental study on local scour around a pile in a silty bed under combined waves and current 波流联合作用下粉质河床桩周局部冲刷试验研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-25 DOI: 10.1016/j.oceaneng.2026.124401

Chunguang Yuan , Na Zhang , Mingxiao Xie , Dake Chen , Jinquan Wang , Xiaoliang Xia

Scouring at monopile foundations constitutes a critical geotechnical hazard compromising the stability of offshore installations. Contemporary understanding of seabed erosion is predominantly based on coarse-grained sandy sediments, whereas the erosional behavior of silty beds—characterized by their liquefaction susceptibility and distinct transport mechanisms—remains insufficiently explored. This study presents a systematic experimental investigation of equilibrium scour depths around slender cylindrical piles in silty soils under high Keulegan–Carpenter (KC) number conditions. Results indicate that the critical KC number for scour initiation in silt is as low as 2.7, significantly lower than the value of 6 established for sandy beds. Under wave-alone conditions, scour depth in silt increases monotonically with the relative Shields parameter, contrasting with the non-monotonic trend observed in sand. For combined wave–current conditions, scour depth in silt exhibits a non-monotonic relationship with relative current strength

U_{c w}

. When wave–current action induces seabed liquefaction, scour depth in silt amplifies to 1.3–1.7 times that in sand under identical KC and

U_{c w}

conditions. A new empirical equation incorporating the relative Shields parameter is proposed, demonstrating enhanced predictive accuracy for scour depth estimation in silty seabeds.

单桩基础冲刷是危及海上设施稳定性的重大岩土工程隐患。目前对海底侵蚀的认识主要基于粗粒度砂质沉积物，而粉质层的侵蚀行为——以其液化敏感性和独特的运输机制为特征——仍然没有得到充分的探索。本文对粉质土中细长柱桩在高KC值条件下的平衡冲刷深度进行了系统的试验研究。结果表明：粉土中起冲临界KC值低至2.7，显著低于砂质层的6；在单波条件下，粉土的冲刷深度随相对盾构参数的增加而单调增加，而砂土则呈非单调趋势。在波流复合条件下，泥沙冲刷深度与相对水流强度Ucw呈非单调关系。在相同的KC和Ucw条件下，波浪流作用诱发海床液化时，淤泥的冲刷深度是砂土的1.3-1.7倍。提出了一个新的包含相对盾构参数的经验方程，提高了粉质海床冲刷深度估计的预测精度。

{"title":"Experimental study on local scour around a pile in a silty bed under combined waves and current","authors":"Chunguang Yuan , Na Zhang , Mingxiao Xie , Dake Chen , Jinquan Wang , Xiaoliang Xia","doi":"10.1016/j.oceaneng.2026.124401","DOIUrl":"10.1016/j.oceaneng.2026.124401","url":null,"abstract":"<div><div>Scouring at monopile foundations constitutes a critical geotechnical hazard compromising the stability of offshore installations. Contemporary understanding of seabed erosion is predominantly based on coarse-grained sandy sediments, whereas the erosional behavior of silty beds—characterized by their liquefaction susceptibility and distinct transport mechanisms—remains insufficiently explored. This study presents a systematic experimental investigation of equilibrium scour depths around slender cylindrical piles in silty soils under high Keulegan–Carpenter (<em>KC</em>) number conditions. Results indicate that the critical <em>KC</em> number for scour initiation in silt is as low as 2.7, significantly lower than the value of 6 established for sandy beds. Under wave-alone conditions, scour depth in silt increases monotonically with the relative Shields parameter, contrasting with the non-monotonic trend observed in sand. For combined wave–current conditions, scour depth in silt exhibits a non-monotonic relationship with relative current strength <span><math><mrow><msub><mi>U</mi><mrow><mi>c</mi><mi>w</mi></mrow></msub></mrow></math></span>. When wave–current action induces seabed liquefaction, scour depth in silt amplifies to 1.3–1.7 times that in sand under identical <em>KC</em> and <span><math><mrow><msub><mi>U</mi><mrow><mi>c</mi><mi>w</mi></mrow></msub></mrow></math></span> conditions. A new empirical equation incorporating the relative Shields parameter is proposed, demonstrating enhanced predictive accuracy for scour depth estimation in silty seabeds.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"351 ","pages":"Article 124401"},"PeriodicalIF":5.5,"publicationDate":"2026-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Two-dimensional numerical study of the wave/current-seabed-overtopping breakwater for energy conversion interaction 波流-底涌防波堤能量转换相互作用的二维数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-24 DOI: 10.1016/j.oceaneng.2026.124364

Yuan Gao , Jie Lin , Jisheng Zhang , Yakun Guo

In recent decades, overtopping breakwater for energy conversion (OBREC) has attracted much attention due to its short investment payback period, providing new development directions for commercial application of wave power extraction. Currently, existing study on OBREC is still in its infancy, focusing mainly on assessing power generation efficiency and ignoring structure stability. Therefore, a program for simulating wave/current-seabed-OBREC interaction is developed in this study to analyze the stability of OBREC. Results show that a relationship between wave reflection coefficient and relative water depth exists, and a S-shape curve fits well to different wave parameters, which is useful for practical engineering. Reservoir overturning may occur due to wave-induced large seepage force on base. Among these, the current velocity has the greatest impact on the vertical force acting on base. When current velocity increases from 0 to 3 m/s, the vertical force increases by approximately 500 %. Analysis reveals that the seabed pore pressure decreases from front toe to back toe of breakwater. Furthermore, momentary liquefaction mainly occurs at the front toe, and the current velocity also has the most significant impact on the liquefaction extent. When u_c = 3 m/s, the maximum liquefaction depth is four times of that for the wave-only case.

近几十年来，能源转换防波堤（OBREC）因其投资回收期短而备受关注，为波浪能提取的商业应用提供了新的发展方向。目前，对OBREC的研究还处于起步阶段，主要集中在发电效率的评估上，忽略了结构的稳定性。因此，本研究开发了一个模拟波/流-海床-OBREC相互作用的程序来分析OBREC的稳定性。结果表明，波浪反射系数与相对水深之间存在一定的关系，并能较好地拟合不同的波浪参数，具有较好的工程应用价值。波浪引起的基底大渗流力可能导致水库倾覆。其中，电流速度对作用在基座上的垂直力影响最大。当电流速度从0米/秒增加到3米/秒时，垂直力增加约500%。分析表明，防波堤的海床孔隙压力由前趾向后趾递减。瞬时液化主要发生在前趾，流速对液化程度的影响也最为显著。当uc = 3 m/s时，最大液化深度是无波情况下的4倍。

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引用次数: 0

Study on the characteristics and prediction model of gas-liquid two-phase slug flow in subsea jumper 水下跳线气液两相段塞流特性及预测模型研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-24 DOI: 10.1016/j.oceaneng.2026.124388

Wenrui Song , Wenhua Li , Shanying Lin , Haoran Ye , Gen Li

Subsea jumpers connect wellheads to subsea facilities and transport produced multiphase fluids. Their three-dimensional geometry, combined with gas–liquid property contrasts, promotes slug flow, which intensifies pressure fluctuations and energy losses, thereby threatening structural integrity and operational safety. This study integrates experiments and numerical simulations to investigate gas–liquid slug flow in a typical M-shaped jumper (48 mm ID, 3.6 m in length, and a 1.0 m elevation difference). Over the tested range of mixture velocity V_M = 1–12 m/s and gas volume fraction

α_{g}

= 0.2–0.8, extensive slug statistics were collected to quantify slug velocity, length, and frequency, and to elucidate slug evolution within the jumper and the associated hydrodynamic loads on the bends. The results show that the pressure-load amplitude decreases progressively from the first to the last bend, owing to momentum attenuation induced by flow-direction changes and the cumulative pressure drop along the jumper. On this basis, predictive correlations for slug velocity, length, and frequency were developed for the M-shaped jumper, with maximum prediction errors below 10 %. These findings improve understanding of slug flow dynamics and load characteristics in subsea jumpers, supporting design optimization and safe multiphase transport.

海底跳线将井口连接到海底设施，并运输生产的多相流体。它们的三维几何形状，结合气液性质的对比，促进了段塞流，加剧了压力波动和能量损失，从而威胁到结构的完整性和操作安全。本研究将实验和数值模拟相结合，研究了典型m型跳线（内径48 mm，长度3.6 m，高程差1.0 m）中的气液段塞流。在混合速度VM = 1 ~ 12 m/s，气体体积分数αg = 0.2 ~ 0.8的测试范围内，收集了大量的段塞统计数据，量化了段塞的速度、长度和频率，并阐明了段塞在跳线内的演变以及相关的弯头水动力载荷。结果表明，从第一个弯道到最后一个弯道，压力载荷幅值逐渐减小，这主要是由于流动方向变化引起的动量衰减和跨跃段的累积压降造成的。在此基础上，对m型跳线建立了段塞速度、长度和频率的预测相关性，最大预测误差低于10%。这些发现提高了对水下跳桥段塞流动力学和载荷特性的理解，为设计优化和安全多相输送提供了支持。

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引用次数: 0

Power generation maximization framework with particle swarm optimization for ocean current turbine farms 基于粒子群优化的海流涡轮电场发电最大化框架

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-24 DOI: 10.1016/j.oceaneng.2026.124195

E. Baris Ondes , Cornel Sultan , James H. Vanzwieten

This paper presents an optimization framework for enhancing power generation in ocean current turbine (OCT) farms by arranging turbines within a defined spatial area. The turbines are anchored to the ocean floor and dynamically positioned to capture maximum energy from ocean currents. The optimization process accounts for turbine wake interactions, which can reduce efficiency if not properly managed. A Particle Swarm Optimization (PSO) algorithm is used to determine the turbine layout that maximizes the farm’s average power output within the constrained domain. By integrating a wake model into the optimization loop, the framework significantly improves the farm’s average power output, yielding power gains of 41–63% across arrays of 9, 16, and 25 turbines. This approach offers a fast and reliable solution for maximizing energy production, providing valuable insights into optimal turbine density and placement for future OCT farm designs.

本文提出了一个优化框架，通过在确定的空间区域内布置涡轮机来增强海流涡轮机（OCT）农场的发电能力。涡轮机固定在海底，动态定位以从洋流中获取最大能量。优化过程考虑了涡轮尾迹相互作用，如果管理不当会降低效率。采用粒子群优化（PSO）算法确定在约束域内使电场平均输出功率最大化的涡轮机布局。通过将尾流模型集成到优化回路中，该框架显著提高了农场的平均功率输出，在9、16和25台涡轮机的阵列中产生41-63%的功率增益。这种方法为最大限度地提高能源产量提供了快速可靠的解决方案，为未来OCT农场设计的最佳涡轮机密度和位置提供了有价值的见解。

引用次数: 0

From single-modal to multi-modal: How does multi-modal data integration enhance the precision of seafarer fatigue detection? 从单模态到多模态：多模态数据集成如何提高海员疲劳检测的精度？

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-24 DOI: 10.1016/j.oceaneng.2026.124302

Liu Yang , Yapeng Lyu , Luyao Li , Yue Ma , Qing Liu

Seafarer fatigue, stemming from monotonous navigational tasks and high work pressure, significantly increases accident risk. Existing studies often lack accuracy and reliability, relying on single-modal, simulated data. To fill this gap, this study conducted a 24-day real navigation experiment, collecting physiological (EEG, EDA, ECG) and psychological (Psych) data from 24 seafarers, yielding 212 labeled samples. Next, a total of 32-dimensional fatigue features were extracted from the multi-modal data, and a feature layer fusion strategy was proposed. Eight machine learning algorithms (including DT, KNN, SVM, ANN, RF, AdaBoost, XGBoost, and LightGBM) were then used to establish the multi-modal fatigue recognition model. The dataset was split 7:3 (train/test), with class imbalance corrected using SMOTE. Model performance was subsequently evaluated on the held-out test set using accuracy, precision, recall, and F1-score as primary indicators. A thorough comparison between single-modal, bi-modal, and multi-modal situations was conducted. The results indicated that the multi-modal approach (integrating EEG, EDA, ECG, and Psych) significantly outperforms other methods. The LightGBM model achieved a maximum accuracy of 95.93 %. This study contributes to more effective fatigue detection, enhancing seafarer management and navigation safety.

由于航海任务单调、工作压力大，海员疲劳大大增加了事故发生的风险。现有的研究往往缺乏准确性和可靠性，依赖于单模态的模拟数据。为了填补这一空白，本研究进行了为期24天的真实导航实验，收集了24名海员的生理（EEG， EDA， ECG）和心理（Psych）数据，产生了212个标记样本。其次，从多模态数据中提取32维疲劳特征，并提出特征层融合策略；采用DT、KNN、SVM、ANN、RF、AdaBoost、XGBoost、LightGBM等8种机器学习算法建立多模态疲劳识别模型。数据集分成7:3（训练/测试），使用SMOTE校正类不平衡。随后在hold -out测试集上以准确性、精密度、召回率和f1分数作为主要指标评估模型的性能。对单模态、双模态和多模态情况进行了全面的比较。结果表明，多模态方法（整合EEG、EDA、ECG和心理）显著优于其他方法。LightGBM模型的最大准确率为95.93%。该研究有助于更有效的疲劳检测，加强船员管理和航行安全。

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引用次数: 0