Ocean Engineering最新文献_第4页

Research on bow slamming loads and whipping response's characteristics in hydroelastic experiment by FBG method 用光纤光栅法研究船首撞击载荷及水弹试验中摆动响应特性

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-31 DOI: 10.1016/j.oceaneng.2026.124434

Yiwen Wang , Hantao Zhang , Miaozhu Wang , Xiangshao Kong , Cheng Zheng , Guangyu Tian , Yuran Li

Under severe sea states with significant bow emergence and immersion, violent ship relative motion induces substantial bow structural slamming loads. Slamming loads induce structural whipping response, sharply increasing overall structural stress and severely threatens ship safety. In order to investigate characteristics of slamming loads and whipping response under wave, this research conducted segmented variable cross-section backbone hydroelastic model experiment, in which were firstly utilized FBG (Fiber Bragg Grating) method to measure and analyze the whipping response of the ship. The research analyzes slamming loads on the ship bow by integrating the bow wave entry motion. Furthermore, it investigates the whipping response and explores the correlations between slamming loads and whipping response. The results confirmed the reliability of FBG method in measuring whipping response. Severe slamming loads on the bow caused the 2nd harmonic response component amplitude to reach 60.81 % of the wave frequency component. The superposition of multi-order harmonic responses leads to a 72.35 % increase in the sagging bending moment. This research analyzes the bow motion, slamming loads, whipping response and ship structural responses by FBG method. It provides a reference for the application of FBG method in measuring the whipping response under nonlinear wave loads.

在严重的船首出沉海况下，剧烈的船舶相对运动引起了巨大的船首结构撞击载荷。冲击载荷引起结构的振荡响应，使结构整体应力急剧增大，严重威胁船舶安全。为了研究船舶在波浪作用下的甩动载荷和甩动响应特性，本研究进行了分段变截面骨干水弹性模型试验，首次利用光纤光栅（FBG）方法对船舶的甩动响应进行了测量和分析。通过对船首波进入运动的积分分析，分析了船首的撞击载荷。此外，还研究了鞭挞响应，并探讨了鞭挞载荷与鞭挞响应之间的关系。结果证实了FBG法测量振荡响应的可靠性。船首剧烈的撞击载荷使二次谐波响应分量幅值达到了波频分量的60.81%。多阶谐波响应的叠加使弯曲弯矩增大72.35%。本文采用光纤光栅法分析了船首运动、冲击载荷、摆动响应和船舶结构响应。为光纤光栅法测量非线性波浪载荷下的振荡响应提供了参考。

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引用次数: 0

Finite-time trajectory tracking of air cushion vehicles under dynamic event-triggered control and unknown disturbances 动态事件触发控制和未知干扰下气垫飞行器的有限时间轨迹跟踪

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2026.124276

Bingjia Chi , Yuanhui Wang , Yang Hao , Yitian Guan

In this research, we propose a finite-time dynamic event-triggered control strategy with communication optimization for air cushion vehicle (ACV) trajectory tracking under the influence of high-frequency actuator activity, external disturbances, and model uncertainties. While a finite-time observer estimates and compensates for aggregated unknown disturbances in real time, a backstepping-based finite-time controller is created to guarantee rigorous finite-time convergence of the tracking error. A dynamic event-triggered control (DETC) system modifies control inputs only in response to certain triggering conditions, therefore reducing communication burden and suppressing unnecessary actuator activities. Using Lyapunov theory, the closed-loop system's finite-time stability is convincingly demonstrated. In comparison to traditional backstepping and integral sliding mode control techniques, two case studies demonstrate that the suggested approach provides faster convergence, significantly reduces communication demands, and mitigates actuator wear.

在本研究中，我们提出了一种具有通信优化的有限时间动态事件触发控制策略，用于气垫车辆（ACV）在高频执行器活动、外部干扰和模型不确定性影响下的轨迹跟踪。在有限时间观测器实时估计和补偿聚集的未知干扰的同时，创建了基于反步的有限时间控制器以保证跟踪误差的严格有限时间收敛。动态事件触发控制（DETC）系统仅在响应某些触发条件时修改控制输入，从而减少通信负担并抑制不必要的执行器活动。利用李雅普诺夫理论，令人信服地证明了闭环系统的有限时间稳定性。与传统的反演和积分滑模控制技术相比，两个案例研究表明，该方法具有更快的收敛速度，显著降低了通信需求，并减轻了执行器的磨损。

引用次数: 0

CFD–DEM-based design and optimization of a new mechanical collector for deep-sea nodules 基于cfd - dem的新型深海结核机械收集器的设计与优化

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2026.124443

Qiang Yang , Dingbang Wei , Meilin Liu , Jianxin Xia

With the sustained growth in demand for battery-metal resources, global attention is shifting to the commercial development of deep-sea nodules. To address the large environmental disturbance, structural complexity, or scale limitations of mainstream collection methods, this study validates a novel rotary-rake mechanical collector using a coupled computational fluid dynamics and discrete element method (CFD-DEM) approach. Under representative mining conditions, we elucidate the operating principle of the rotary-rake collection process and establish a design methodology for key parameters. The compound motion of rake-tine components is captured with an overset-grid method, and simulations analyze near-bed flow dynamics under different rotational and traveling speeds. Focusing on collection performance and landing-position distribution, we further obtain optimized parameters for optimal nodule collection and provide guidance for stacking-zone layout. Finally, water-tank experiments with mixed-size nodules corroborated the coupled CFD-DEM results. Results indicate that, within the selected operating window, increasing rotational speed has a minor effect on near-bed velocity and pressure, whereas traveling speed has a pronounced impact on the stacking-zone layout and nodule landing distribution. Under the combined constraints of low seabed disturbance and effective collection, the recommended settings are

ω_{r}

= 26 rpm and

v_{m}

= 0.5 m/s. This study provides a new pathway for designing efficient, low-disturbance deep-sea mining systems.

随着电池金属资源需求的持续增长，全球的注意力正转向深海结核的商业开发。为了解决大型环境干扰、结构复杂性或主流收集方法的规模限制问题，本研究使用耦合计算流体动力学和离散元法（CFD-DEM）方法验证了一种新型旋转耙式机械收集器。在具有代表性的采矿条件下，阐明了旋耙收集工艺的工作原理，建立了关键参数的设计方法。采用过置网格法捕获了坡时分量的复合运动，并对不同转速和移动速度下的近床流动力学进行了仿真分析。针对收集性能和着陆点分布，进一步得到最优结核收集的优化参数，为堆区布置提供指导。最后，混合大小结核的水箱实验证实了CFD-DEM的耦合结果。结果表明，在选择的操作窗口内，增加转速对近层速度和压力的影响较小，而移动速度对堆积区布局和结核降落分布的影响较大。在低海床扰动和有效采集的综合约束下，推荐设置ωr = 26 rpm, vm = 0.5 m/s。该研究为设计高效、低扰动的深海采矿系统提供了新的途径。

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引用次数: 0

Feasibility assessment of zero-emission high-speed passenger vessels using optimal energy scheduling and power allocation 基于最优能量调度和动力分配的高速客船零排放可行性评估

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2026.124430

Samieh Najjaran , Ingrid Sundvor , Rebecca Jayne Thorne , Roger Skjetne

The transition of existing high-speed passenger vessels (HSPVs) to zero-emission alternatives requires a feasibility assessment of potential retrofit solutions. This study investigates whether a conventional HSPV can be retrofitted with a zero-emission power system by evaluating two approaches: iterative vessel redesign and fixed-size retrofit. The iterative approach, employing a resistance model and an optimization-based energy management method with high computational efficiency, adjusts vessel dimensions to accommodate the added weight of two different hybrid power system configurations—a non-plugin hybrid system and a plugin hybrid system—both consisting of a fuel cell (FC) and a battery energy storage system (BESS). The fixed-size retrofit approach assesses the feasibility of a BESS-only power system with shoreside charging or battery swapping. The assessment is conducted for the case of an HSPV operating along the coastal region of Norway, the MS Elsa Laula Renberg. Results reveal that retrofitting with hybrid power systems requires iterative vessel adjustments, where a plugin hybrid case with shoreside charging becomes the lightest solution. In contrast, retrofitting the vessel with a BESS under the specified setup without hull modifications is infeasible due to excessive weight. However, a prospective analysis shows that advances in battery technology could make the fixed-size retrofit feasible.

现有高速客船（hspv）向零排放替代方案的转变需要对潜在的改造解决方案进行可行性评估。本研究通过评估船舶迭代重新设计和固定尺寸改造两种方法，探讨了传统HSPV是否可以采用零排放动力系统进行改造。迭代方法采用阻力模型和基于优化的能量管理方法，具有较高的计算效率，可调整容器尺寸以适应两种不同混合动力系统配置的增加重量-非插件混合动力系统和插件混合动力系统-两者都由燃料电池（FC）和电池储能系统（BESS）组成。固定规模的改造方法评估了只有bess的电力系统与岸上充电或电池交换的可行性。该评估是针对在挪威沿海地区活动的HSPV， MS Elsa Laula Renberg进行的。结果表明，使用混合动力系统进行改造需要反复调整船舶，其中带有岸边充电的插件混合动力箱成为最轻的解决方案。相比之下，在没有修改船体的情况下，在指定的设置下用BESS改造船只是不可行的，因为重量过重。然而，一项前瞻性分析表明，电池技术的进步可以使固定尺寸的改造成为可能。

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引用次数: 0

Buoy effects on low-frequency dynamics of catenary moorings for floating offshore wind turbines 浮筒对海上浮式风力发电机悬链线系泊低频动力学的影响

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2026.124417

Evans Korankye Frimpong, Kevin Pope, Xili Duan

In this paper, experimental results on the dynamic response and damping behaviors of mooring lines with forced horizontal oscillations are presented. To represent conditions representative of a floating wind turbine, experiments were conducted at 1:60 scale in a 2 m deep towing tank using two mooring configurations: a bare catenary and a buoy-assisted catenary. Sinusoidal surge motions were imposed at the fairlead using a programmable linear actuator, covering a range of amplitudes (0.083–0.417 m) and periods (6.455–38.730 s). Fairlead tension was measured using an in-line load cell, while top-end angles were extracted from high-speed videos at 100 fps. Energy dissipation was quantified from force–displacement cycles using indicator diagrams. Results show that the bare catenary dissipated more energy at smaller amplitudes, while the buoy-assisted configuration became more effective at higher amplitudes due to a transition into a taut regime. Slack–snap behavior observed in the buoy-assisted case led to nonlinear responses and dynamic tension peaks up to 8.23 times the minimum value. The bare catenary had a strong linear relationship between dissipated energy and the excitation parameter, ω²q³.

本文给出了受强迫水平振动作用下系泊索的动力响应和阻尼特性的实验结果。为了代表浮动式风力涡轮机的条件，实验以1:60的比例在一个2米深的拖曳槽中进行，使用两种系泊配置：裸悬链线和浮筒辅助悬链线。使用可编程线性执行器在导联处施加正弦浪涌运动，覆盖幅度（0.083-0.417 m）和周期（6.455-38.730 s）。Fairlead张力使用在线测压元件测量，而顶部角度则以100 fps的速度从高速视频中提取。能量耗散是量化的力-位移周期使用指示图。结果表明，裸悬链线在较小的振幅下耗散更多的能量，而浮标辅助悬链线在较高的振幅下由于过渡到紧绷状态而变得更有效。在浮筒辅助情况下观察到的松弹行为导致非线性响应，动态张力峰值高达最小值的8.23倍。裸悬链线的耗散能与激发参数ω2q3之间有很强的线性关系。

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引用次数: 0

SynPER: Synthesized prioritized experience replay for USVs formation control in island-reef waters via multi-agent reinforcement learning SynPER：基于多智能体强化学习的岛礁水域usv编队控制的综合优先体验回放

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2025.124080

Zijian Hu , Jiangyong Jin , Yani Cui , Bo Li , Jia Ren , Fan Yang

Multi-unmanned surface vehicle (multi-USV) systems have emerged as promising platforms for maritime applications. Ensuring safe and reliable formation control in complex, dynamic, and unknown marine environments is critical to the success of multi-USV missions. In this paper, we formulate the multi-USV formation control problem as a Markov decision process (MDP) and propose an advanced off-policy deep reinforcement learning (DRL) method, the synthesized prioritized experience replay (SynPER) algorithm, to address the critical challenge of low sample efficiency. First, SynPER introduces a hybrid neural network architecture based on Kolmogorov–Arnold networks (KAN) to improve feature representation and interpretability. Subsequently, a asynchronous multi-agent hindsight experience replay (AMAHER) that generates diverse virtual targets for efficient experience augmentation is designed. In addition, an individual prioritized experience replay (IPER) strategy that enables agents to focus on experiences most relevant to its own policy convergence is introduced. Evaluated in a large-scale simulated island-reef waters environment calibrated with parameters from the “Linghang #1” USV, SynPER achieves a 50.27% improvement in convergence speed and a 17.87% gain in final performance compared to the multi-agent deep deterministic policy gradient (MADDPG) baseline. Extensive tests across varied complex scenarios further validate the robustness, adaptability, and formation stability of SynPER, underscoring its potential for real-world deployment.

多无人水面车辆（multi-USV）系统已经成为海上应用的有前途的平台。确保在复杂、动态和未知的海洋环境中安全可靠的编队控制是多无人潜航器任务成功的关键。本文将多usv编队控制问题描述为马尔可夫决策过程（MDP），并提出了一种先进的非策略深度强化学习（DRL）方法，即综合优先体验重放（SynPER）算法，以解决低样本效率的关键挑战。首先，SynPER引入了一种基于Kolmogorov-Arnold网络（KAN）的混合神经网络架构，以提高特征表示和可解释性。随后，设计了一种异步多智能体后见经验重放（AMAHER）系统，该系统能够生成多种虚拟目标，从而实现高效的后见经验增强。此外，还引入了个体优先体验重放（IPER）策略，该策略使代理能够专注于与其自身策略收敛最相关的体验。在使用“岭航一号”USV参数校准的大型模拟岛礁水域环境中进行评估，与多智能体深度确定性策略梯度（madpg）基线相比，SynPER的收敛速度提高50.27%，最终性能提高17.87%。在各种复杂场景中进行的大量测试进一步验证了SynPER的鲁棒性、适应性和地层稳定性，强调了其在实际部署中的潜力。

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引用次数: 0

Threshold criteria for silt movement and suspension on sloped bed under waves 波浪作用下坡床泥沙运动和悬浮的阈值准则

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2026.124469

Kezhao Fang , Bin Li , Zaijin You , Zhaowei Wang , Jie Xu

The incipient movement and suspension of coastal silt on a sloped bed are experimentally investigated in a wave flume under non-breaking regular waves. The laboratory experiment was conducted in a wave flume of 60 m long, 2 m wide, and 1.8 m deep with a sloped bed of sediment (β ≈ 6.0^o and d₅₀ = 0.038 mm). The incipient movement or suspension of silty sediment was determined visually by slowly varying wave height and period until a few sediment grains started to move or suspend from the sloped bed. The suspended sediment concentrations were also recorded with Argus-IV meters to provide an independent determination of the incipient motion and suspension of silt. Sixteen wave gauges and three Acoustic Doppler Velocimeters were used to collect the data of wave heights, periods, and wave orbital velocities in all the experimental runs, respectively. With the collected data analyzed, the onset wave velocity U₀ for incipient motion or suspension of silty sediment on the sloped bed is found to be a simple function of the nondimensional immersed sediment weight S_* and the relative bed roughness d₅₀/A, where A is the semi-excursion amplitude of wave orbital motion close to the bed and d₅₀ is the sediment median diameter. The presently available models developed for horizontal beds of sand are found to generally overestimate the onset velocities of silty sediment on the sloped bed. Theoretical formulations were further derived in this study to quantitatively explain why the onset velocity U₀ on a sloped bed is always smaller than that on a horizontal bed under waves.

在波浪水槽中试验研究了不规则波浪作用下斜坡河床上海岸泥沙的初始运动和悬浮。室内试验在长60 m、宽2 m、深1.8 m的波浪水槽中进行，坡床沉积物（β≈6.00,d50 = 0.038 mm）。粉质沉积物的初期运动或悬浮是通过缓慢变化的波高和周期来直观地确定的，直到一些沉积物颗粒开始从倾斜的床上移动或悬浮。悬浮物浓度也用阿格斯- iv型测量仪记录下来，以提供泥沙初动和悬浮物的独立测定。利用16台测波仪和3台多普勒测速仪分别采集了各次实验的波高、波周期和波轨道速度数据。通过对采集数据的分析，发现斜坡床上粉质泥沙初动或悬浮的起始波速U0是无量纲沉沙重S*和相对河床粗糙度d50/ a的简单函数，其中a为靠近河床的波轨道运动半偏移幅度，d50为沉积物中位直径。现有的水平砂层模型普遍高估了斜坡砂层粉质泥沙的起沙速度。本研究进一步推导了理论公式，定量解释了波浪作用下斜坡层的起始速度U0总是小于水平层的原因。

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引用次数: 0

Numerical investigation of the secondary load cycle and high-frequency response on a vertical cylinder under focused waves 聚焦波作用下垂直圆柱体二次载荷循环及高频响应的数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-30 DOI: 10.1016/j.oceaneng.2026.124428

Aqin Wang , Hong Song , Zhixin Zhao , Shuang Chang

High-frequency resonant responses induced by extreme waves pose significant threats to the safety of marine structures. A three-dimensional numerical wave tank is established to investigate the wave forces and dynamic response of a vertical cylinder subjected to focused waves, with particular emphasis on the characterization and mechanism of the secondary load cycle (SLC) and its role in exciting high-frequency structural vibrations. Time-frequency analysis identifies the SLC as a strongly nonlinear, high-frequency load component that elevates the peak frequency content of the total wave force. Spatially, the SLC is primarily confined to a region within 0.2 m below the still water level, where its amplitude increases with wave nonlinearity and relative cylinder size. Analysis of pressure distribution and vortex shedding characteristics reveals that SLC is primarily attributed to the low-pressure vortex structures formed by the added water mass on the leeward side of the cylinder after the passage of the wave crest. As wave steepness increases, the high-frequency content in the load grows, significantly amplifying high-frequency structural responses across different frequency ratios. Furthermore, the SLC shifts the timing of the highest frequency components in both wave forces and structural responses. A comparative analysis confirms that the SLC substantially amplifies these high-frequency responses, with the amplification effect generally increasing with wave steepness. The high-frequency load components associated with the SLC play a critical role in the high-frequency dynamic behavior of the structure, necessitating careful consideration under extreme wave conditions.

极端波浪引起的高频共振响应对海洋结构物的安全构成重大威胁。建立了三维数值波槽，研究了垂直圆柱体在聚焦波作用下的波浪力和动力响应，重点研究了二次载荷循环（SLC）的特征和机理及其在激发高频结构振动中的作用。时频分析表明，SLC是一种强烈的非线性高频载荷分量，它提高了总波浪力的峰值频率含量。在空间上，SLC主要局限于静止水位以下0.2 m范围内，其振幅随波浪非线性和相对圆柱尺寸的增大而增大。对压力分布和旋涡脱落特征的分析表明，SLC的主要原因是在波峰通过后，圆筒背风侧增加的水团形成了低压旋涡结构。随着波浪陡度的增加，荷载中的高频含量增加，显著放大了结构在不同频率比下的高频响应。此外，SLC改变了波浪力和结构响应中最高频率分量的时间。对比分析证实，SLC实质上放大了这些高频响应，并且放大效果通常随波陡度增加而增加。与SLC相关的高频载荷分量对结构的高频动力性能起着至关重要的作用，在极端波浪条件下需要仔细考虑。

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引用次数: 0

Adaptive high-gain observer for floating offshore wind turbines with HIL validation 浮式海上风力发电机自适应高增益观测器的HIL验证

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.oceaneng.2026.124402

Hassan Rafia , Hamid Ouadi , Abdelaziz El Aoumari , Fatima-Zahra Chaoui , Anis Boulal , Fouad Giri

This paper proposes an Adaptive High-Gain Observer (AHGO), which is capable of reconstructing the platform’s displacements and velocities using only position measurements. The observer is based on a structural model with unknown, time-varying parameters that depend on the turbine’s operating conditions, including wind, wave, and current interactions. Real-time adaptation of these parameters enhances robustness of the estimation under nonlinear and coupled dynamics. A Lyapunov-based stability analysis is also provided to guarantee convergence of the adaptation-estimation scheme. To evaluate the contribution of parameter adaptation, six independent observers were implemented, one for each degree of freedom (DOF) of the FOWT platform. A direct comparison was carried out between the Adaptive High-Gain Observer (AHGO), the Fixed-Parameter High-Gain Observer (FHGO) and the Kalman Filter Observer (KFO). All observers were tested under identical operating conditions using a MATLAB/Simulink-OpenFAST co-simulation of a semi-submersible FOWT platform. The results demonstrate that the AHGO significantly enhances estimation accuracy, achieving reductions in root mean square error (RMSE) of up to 57.5% compared to the KFO for surge motion. Furthermore, the real-time feasibility of the AHGO was validated through hardware-in-the-loop (HIL) experiments conducted on the dSPACE DS1104 platform.

本文提出了一种自适应高增益观测器（AHGO），该观测器仅使用位置测量就能重建平台的位移和速度。观测器基于一个结构模型，该模型具有未知的时变参数，这些参数取决于涡轮机的运行条件，包括风、波浪和电流的相互作用。这些参数的实时自适应增强了在非线性和耦合动力学下估计的鲁棒性。为了保证自适应估计方案的收敛性，给出了基于lyapunov的稳定性分析。为了评估参数自适应的贡献，实现了6个独立观测器，每个观测器对应于fot平台的每个自由度。对自适应高增益观测器（AHGO）、固定参数高增益观测器（FHGO）和卡尔曼滤波观测器（KFO）进行了直接比较。所有观测器在相同的操作条件下使用半潜式FOWT平台的MATLAB/Simulink-OpenFAST联合仿真进行测试。结果表明，AHGO显著提高了估计精度，与KFO相比，对浪涌运动的均方根误差（RMSE）降低了57.5%。此外，在dSPACE DS1104平台上进行了硬件在环（HIL）实验，验证了AHGO的实时性可行性。

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引用次数: 0

Practical considerations in directional decomposition of response spectra from time-domain measurements using relative RAO method 相对RAO方法在时域测量响应谱定向分解中的实际考虑

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-29 DOI: 10.1016/j.oceaneng.2026.124436

Taehyun Yoon , Chungkuk Jin , Young IL. Park , Minsung Chun , Jeong-Hwan Kim

This study investigates the practical aspects of applying the relative RAO-based directional decomposition method to reconstruct response spectra from time-domain motion measurements. While the theoretical framework of the method assumes ideal frequency-domain inputs with perfectly preserved phase information, actual applications rely on time-series data that must be preprocessed and converted into frequency spectra, inevitably introducing phase distortion and statistical uncertainty. Through systematic reconstruction tests using synthesized motion data, this study identifies the key factors that affect the stability and accuracy of the decomposition process. The results show that while auto spectra alone can provide sufficiently consistent energy distributions, the inclusion of cross spectra may deteriorate the reconstruction if phase coherence is not well maintained. This instability arises from signal-length limitations, spectral leakage, and imperfect phase alignment during frequency transformation. Based on these findings, practical guidelines are proposed for reliable implementation: phase-consistent signal preprocessing, normalization between auto and cross spectra, and adequate signal duration to ensure coherence. These considerations bridge the gap between theoretical reconstruction and field measurements, providing a practical foundation for digital-twin-based monitoring of ships and offshore structures using real-time motion data.

本研究探讨了应用基于相对定向分解的方法从时域运动测量中重建响应谱的实际问题。虽然该方法的理论框架假设了具有完美保存相位信息的理想频域输入，但实际应用依赖于必须经过预处理并转换为频谱的时间序列数据，这不可避免地引入了相位失真和统计不确定性。通过对合成运动数据的系统重构试验，确定了影响分解过程稳定性和准确性的关键因素。结果表明，虽然单独使用自动光谱可以提供足够一致的能量分布，但如果相位相干性不能很好地保持，交叉光谱的包含可能会使重建结果恶化。这种不稳定性是由信号长度限制、频谱泄漏和频率变换过程中不完善的相位对准引起的。基于这些发现，提出了可靠实现的实用指南：相位一致的信号预处理，自动和交叉光谱之间的归一化，以及足够的信号持续时间以确保相干性。这些考虑弥补了理论重建和现场测量之间的差距，为利用实时运动数据对船舶和海上结构进行基于数字孪生的监测提供了实践基础。

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引用次数: 0