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Local scour around the monopile: A microscopic perspective using CFD-DEM Ocean Eng. (IF 5.0) Pub Date : 2024-03-05 Ziying Zheng, Zheng Hu, Xingguo Xie, Wei Huang
Local scour around monopile has long been recognized as a culprit of the instability of offshore bridges and wind turbines, prompting numerous investigations in recent decades. To investigate the full process and the micromechanics of local scour, a three-dimensional model comprising a monopile, sandy seabed and water flow is established, considering multiple hydraulic conditions using the coupled
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Multi-sensor cross-domain fault diagnosis method for leakage of ship pipeline valves Ocean Eng. (IF 5.0) Pub Date : 2024-03-05 Zhengjie Liu, Xiaohui Yang, Yingchun Xie, Mengmeng Wu, Zhixiong Li, Weilei Mu, Guijie Liu
The operating environments of ship pipeline valves are complicated. A single sensor may struggle to comprehensively characterize the valve fault features. Pressure variations in the pipeline network may result in changes of the feature distribution of the valve leakage acoustic emission (AE) signals, which makes it challenging for traditional data-driven detection models to achieve satisfactory generalization
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Ship collision mitigation for offshore wind turbine monopile foundations via high-general/low-collision-stiffness steel fenders Ocean Eng. (IF 5.0) Pub Date : 2024-03-05 Yuhao Nie, Hui Fang, Xiangjian Meng
A novel steel fender assembly with quasinegative stiffness (QNS), which provides a system of high stiffness for low general loads and a low stiffness for high-impact collisions designed for mitigating ship collisions with offshore wind turbine (OWT) foundations, was proposed. According to the finite element modeling (FEM) method, a viscoelastic fender with a high initial stiffness exhibited the largest
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Underactuated MSV path following control via stable adversarial inverse reinforcement learning Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Lingyu Li, Yong Ma, Defeng Wu
Model-based control approaches are inadequate to solve the marine surface vehicle (MSV) path-following problem, especially under adverse environments. To effectively deal with the MSV path-following problem, model-free deep reinforcement learning (DRL) based methods have been developed. However, defining an efficient reward function for DRL in path following tasks is rather difficult. Providing expert
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Selfish or cooperative? Understanding the behavior of ships during an overtaking process from the spatiotemporal perspective—A case study of Qingdao Port, China Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Liye Zhang, Zhicheng Ma, Jigang Liu, Shijiang Liu, Jie Song
To understand the behaviors of ships at different stages of an encounter, this article analyzes the relative motion of ships during an overtaking process spatiotemporally. It takes the shortest distance between two ships as a boundary and uses the Douglas–Peuker algorithm and the difference algorithm to identify the critical points of the ship’s courses and speeds. The developed approach was demonstrated
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Investigating the design and arrangement of dual submerged vanes as mitigation countermeasure of bridge pier scour depth using a numerical approach Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Mehdi Hamidi, Mehran Sadeqlu, Ali Mahdian Khalili
In this research, dual submerged vanes have been installed in various arrangements to reduce the bridge pier scour. The analysis results achieved from the FLOW-3D numerical model were utilized with the experimental data and statistical indexes such as RE (%), R, RMSE, and MAE were computed to validate it. The effects of height (), length (), installation angle (), position angle (), and the distance
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Experimental study of low-cycle fatigue crack propagation in hull stiffened plates with symmetric and asymmetric cracks Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Yuelin Song, Zhi Xu, Jiping Zhang, Guoqiang Li, Ping Yang
This study aims to experimentally investigate low-cycle fatigue (LCF) crack growth behavior in both plates and stiffeners, comparing the effects of symmetric and asymmetric crack damage. For this purpose, a stiffened plate specimen with a central stiffener is designed, and initial crack defects (both symmetric and asymmetric with respect to the stiffener) are prefabricated on the specimens. The correlation
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Research on a coupled system design for mineral lifting and wastewater drainage in deep-sea mining applications Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Yajuan Kang, Kaile Wang, Qiong Hu, Shaojun Liu
Deep-sea mining requires lifting minerals from the seabed, at depths of thousands of meters, to the surface. Presently, the most prevalent method involves the use of hydraulic pipeline lifting systems. Meanwhile, for environmental protection requirements, returning the dewatered mining wastewater from the mining vessel back to the seabed for drainage is also becoming a standard practice. However, there
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A data-driven data-augmentation method based on Slim-generative Adversarial Imputation Networks for short-term ship-motion attitude prediction Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Xiaoyu Geng, Qian Sun, Yibing Li, Sitong Zhang, Zitao Zhou, Yifan Wang
The performance of data-driven complex ship-motion attitude prediction models not only depends on the structure and algorithm design of the model but is also affected by the quantity and quality of training samples. Insufficient available data, resulting from factors such as low sampling rates and high costs, could inhibit the achievement of optimal prediction accuracy. This limitation in turn increases
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Experimental study on flow kinematics and pressure characteristics of dam break flow Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Hyung Joon Kim, Jong Mu Kim, Jae Hong Kim, Kwang Hyo Jung, Gang Nam Lee
This paper presents an experimental investigation of flow kinematics and pressure characteristics of dam break flow. The experiments were performed in a 2D prismatic channel, obtaining the velocity fields by particle image velocimetry (PIV) measurement for the entire dam break flow, and the shadowgraph image technique was applied to analyze the generation type and flow stage. Pressure sensors were
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Lateral dynamic response of monopile offshore wind turbines in radially softened layered soil Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Teng Wang, Shiwen Yu, Xiaoni Wu, Chao Tang
The dynamic response of monopile offshore wind turbine is highly dependent on the pile-soil interaction model and the soil property. However, there is a lack of efficient and reliable method considering both the soil softening effect and stratification property in the existing dynamic response analysis of monopile offshore wind turbine. This work provided an analytical solution of lateral dynamic stiffness
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Torsional dynamic response of an end-bearing pile in homogeneous unsaturated transversely isotropic soil Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Wenjie Ma, Binglong Wang, Shunhua Zhou, Eng-Choon Leong, Changdan Wang
Considering the soil skeleton to be statically transversely isotropic, the viscous and inertial coupling among three phases, along with the capillary pressure, the torsional dynamic response of an end-bearing pile in homogeneous unsaturated transversely isotropic soil under time-harmonic torsional load is investigated. The separation of variables method is employed to derive the torsional dynamic governing
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Experimental study on the scour characteristics around a jacket foundation under wave actions Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Jisheng Zhang, Hao Chen, Yakun Guo, Fangyu Wang, Dawei Guan, Xu Deng, Dongshuai Hou
With the development of renewable energy, offshore wind farms move towards to deeper sea regions, which necessitates a comprehensive understanding of the stability of foundation structures subject to complex ocean hydrodynamic forces. Although previous studies have investigated the scour characteristics around monopile and pile group foundations in marine environments, scour around the jacket foundations
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Experimental and numerical investigation on the response characteristic of the crane-wharf structure in liquefiable site Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Yi Zhang, Shuang Tian, Liang Tang, Xianzhang Ling
With the wide application of large cranes, what role does the crane play in the response of the pile-supported wharf needs to be carefully considered, but the effect of the crane is often ignored or considered by centralized mass simplification. Experimental and numerical investigation are effective ways to characterize the seismic performance of structures. To investigate the response characteristic
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Tip vortex suppression by using dimpled roughness Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Yang Li, Lingxin Zhang, Fuqiang Deng, Xinzhen Qin, Di Zhao
The application of roughness on the blade surfaces is an effective and appealing tip vortex cavitation (TVC) suppression technique. However, there are few studies on the suppression of TVC by dimpled roughness, and its physical mechanism remains to be elucidated. In this work, the suppression of TVC on an elliptical foil using dimpled roughness is numerically investigated at a Reynolds number of 4
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A ship equipment reliability evaluation method based on symbolic information and interval-valued q-rung picture fuzzy projection Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Xiaoping Jia, Baozhu Jia
The theoretical reliability of ship equipment is often inconsistent with the practical situation. The scientific evaluation of the actual reliability becomes more challenging due to the increased complexity and the variety of criteria. This study presents a multi-attribute group decision evaluation model based on symbolic information, innovative bidirectional interval-valued -rung picture fuzzy projection
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A hybrid data-driven and learning-based method for denoising low-cost IMU to enhance ship navigation reliability Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Zhaoyi Zhang, Ying Li, Jiyou Wang, Zhichen Liu, Ge Jiang, Hua Guo, Weihang Zhu
Autonomous navigation system is a critical challenge in the development of Maritime Autonomous Surface Ships (MASS). Inertial Navigation Systems (INS) offer an alternative solution for ship autonomous navigation. However, the presence of random noise in the Inertial Measurement Unit (IMU) may compromise the reliability of the navigation system. Therefore, from a data-driven perspective, we propose
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Study on influence coefficients of hydrodynamic force on dynamic response of deep-water pier under earthquake Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Wen Zhang, Xiaopeng Ren, Xiaokun Geng, Yuzhi Zhang, Wanli Yang
The hydrodynamic force generated by the interaction between deep-water pier and water under earthquake exerts a significant influence on the dynamic response of the pier. At present, there is a lack of characterization methods to measure the influence degree of pier-water interaction on the dynamic response of the deep-water pier. Based on the structural dynamics theory and considering the coupling
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Cross-validation strategy for performance evaluation of machine learning algorithms in underwater acoustic target recognition Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Yuanchao Xu, Xiaopeng Kong, Zhiming Cai
The performance evaluation of learning algorithms is essential in underwater acoustic target recognition. Underwater acoustic data typically show temporal structures. However, these structures are frequently ignored when evaluating the performance of learning algorithms, resulting in overestimating predictive accuracy. The similarity analysis of underwater acoustic samples indicates cluster structures
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Comparative study of wave height transformation: Bragg reflection versus wave breaking at submerged rectangular breakwaters Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Ching-Piao Tsai, Chun-Han Ko, Han-Chen Shih, Yueh-Heng Chen, Ying-Chi Chen
This study investigates wave height transformation caused by either a single high-crest or a series of low-crest submerged rectangular breakwaters through laboratory experiments and numerical simulations. The series configuration induces Bragg reflection without wave breaking, while the single breakwater leads to wave breaking. Numerical models, employing two-dimensional RANS equations coupled with
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Bilevel optimization of non-uniform offshore wind farm layout and cable routing for the refined LCOE using an enhanced PSO Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Dongqin Zhang, Zhenqing Liu, Yang Liang, Chao Li, Jize Zhang, Gang Hu
The development of wind power is crucial in addressing the global energy and environmental crises. To enhance wind farm efficiency, a novel bilevel non-uniform optimization approach is proposed to conduct the wind farm layout optimization (WFLO) and electrical cable routing (ECR) simultaneously. Additionally, 2D and 3D wake modelling strategies are investigated and validated to accurately evaluate
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Experimental study on the effect of seepage flow on the tunnel face stability in the saturated ground Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Qiguang Di, Pengfei Li, Mingju Zhang, Youxiu Jia, Shaohua Li, Xiaopu Cui
Maintaining the stability of the tunnel face during the construction of the submarine shield tunnel is the prerequisite for safe construction. A series of face instability model tests under saturated strata were carried out. The earth pressure, the evolution of the soil arch area and the amount of soil entering the soil groove caused by the instability of the tunnel face under different face water
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A self-supervised dual-channel self-attention acoustic encoder for underwater acoustic target recognition Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Xingmei Wang, Peiran Wu, Boquan Li, Ge Zhan, Jinghan Liu, Zijian Liu
Due to the considerable noise and high annotation cost of passive sonar acquisition data challenges, underwater acoustic target recognition (UATR) tasks require novel solutions. In this paper, we propose a self-supervised dual-channel self-attention acoustic encoder (DSAE) for UATR tasks. First, to address the annotation challenge, we design a dual-channel self-attention acoustic encoder to unify features
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Fault-tolerant thrust allocation analysis using metaheuristic optimization algorithms Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Li Xuebin, Yang Luchun
A comprehensive flowchart featuring three optimization models is introduced to ensure compliance with the thrust allocation principle during faults and to improve comprehension of the widely utilized four-part aggregated objective function model in marine control allocation. The evaluation of the system's allocation capability is conducted within Model A. A decision is then made to assess whether the
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Hydrodynamic performance improvement on the hydrofoil using slotted configurations Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Guanzhe Cui, Yicheng Cao, Yan Yan, Wenquan Wang
Hydrofoil is an important component and exerts a significant impact on the performance of hydraulic machinery. Passive flow control can optimize dynamic characteristics and alter turbulent structure around hydrofoil. Slot holds a prominent position due to its efficacy and cost advantage in terms of production and installation. The present study proposes a novel configuration that can enhance the hydrodynamic
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Deformation and splitting of a vortex ring along a thin plate Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Xin Wang, Wen-Li Chen, Xu Chang, Hui Li, Donglai Gao
An experimental study of a vortex ring interacting with a thin flat plate is conducted to explore the intricate dynamics of a vortex ring interacting with a thin flat plate, specifically focusing on the influence of Reynolds number ( = 1000, 3000, 5000 and 7000) on the deformation and splitting behaviors of the vortex ring. To capture the detailed features of the flow field, the Planar Laser Induced
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Surrogate model-based optimization of drogue dimensions and towing operations to straighten deep-towed nonuniform arrays Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Xinyu Li, Xiangqian Zhu, Mingqi Sun, Yanpeng Qu, Kai Liu, Yanliang Pei, Jin-Hwan Choi
In deep-towed multi-channel seismic systems, nonuniform mass distribution of seismic arrays results in a “W” shape, negatively impacting the exploration resolution. High towing speeds or use of large drogues can straighten the arrays; however, these approaches adversely affect the towing depth and maximum cable tension. Therefore, this study performed system optimization for drogue dimensions, towing
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Study on the tropical cyclone-generated waves after ensemble-based assimilation of multi-mission satellite altimeters Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Jincan Liu, Bin Xu, Lu Zhang, Jichao Wang
The third-generation wave model, WAVEWATCH III, is adopted for numerical simulation during the 2020 Atlantic Hurricane Season (AHS). This study examines the effects of data assimilation using significant wave height (SWH) from six satellite altimeters, notably the CRYOSAT-2, JASON-3, SENTINEL-3A, SENTINEL-3B, HY-2B, and CFOSAT. Two packages of wind input and wave dissipation (ST4 and ST6) are compared
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Multihazard resilience and sustainability evaluation of coastal RC bridges under sequential earthquake-tsunami events Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Zhijian Qiu, Athul Prabhakaran, Lei Su, Yewei Zheng
Coastal bridges are particularly prone to damage caused by prior earthquakes, rendering them more vulnerable to subsequent hazards. The potential occurrence of a near-field tsunami can significantly exacerbate this damage, leading to detrimental environmental and economic impacts. Aiming to quantitatively assess these consequences, this study delves into the multihazard resilience and sustainability
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Hydrodynamic performance of an oscillating water column integrated into a hybrid monopile foundation Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Zhao Liu, Yuan Jin, Linquan Cao, Guize Liu, Hao Guo
In this study, a combined concept consisting of an annular oscillating water column device (OWCD) and a bottom-standing offshore wind turbine is considered. Such a system has the ability to harness different types of offshore sustainable energy. The offshore wind turbine is supported by a hybrid monopile foundation, in which the foundation is reinforced by a friction wheel located at the soil surface
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Recent advances in path planning for underwater gliders: A comprehensive review Ocean Eng. (IF 5.0) Pub Date : 2024-03-04 Runfeng Zhang, Bing He, Yanhui Wang, Wei Ma, Shaoqiong Yang
The underwater glider (UG) is a new type of underwater vehicle and has gained enormous attention in the field of ocean observation and detection. Compared with the traditional underwater vehicle, it has the advantages of low noise, low energy consumption, high efficiency, long endurance, and low cost. Due to their low surge speed compared to the ocean current, the UG will yield trajectory bias during
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Probabilistic prediction of spudcan peak penetration resistance based on parameter estimation and sectionalized adaptive linear simplification Ocean Eng. (IF 5.0) Pub Date : 2024-03-02 Xiuqing Yang, Dong Wang, Shaoqing Zhang
Punch-through failure is widely acknowledged as the most common accident during jack-up preload. Evaluating the possibility of punch-through failure is essential for reducing risks in practical operations. However, the predictions of peak penetration resistance are often based on deterministic analyses, where uncertainties related to the soil and model are not taken into account. A new parameter estimation
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Environmental implications of a sandwich structure of a glass fiber-reinforced polymer ship Ocean Eng. (IF 5.0) Pub Date : 2024-03-02 Zhiqiang Han, Jaewon Jang, Jean-Baptiste R.G. Souppez, Daekyun Oh
This study presents the findings related to the selection of composite structures for materials with respect to the effectiveness of their lightweight design and environmental impact during the raw material manufacturing phases. The primary raw materials considered were glass fiber, PVC for the core, and polyester resin. In addition, using the same design conditions, such as bottom load, impregnation
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Experimental investigation on the vortex-induced vibration of a circular cylinder partially covered with moss Ocean Eng. (IF 5.0) Pub Date : 2024-03-02 Hongjun Zhu, Yingmei Li, Hongtao Hao, Md. Mahbub Alam, Tongming Zhou, Tao Tang
This paper reports the water-flume experimental results of the vortex-induced vibration (VIV) of a circular cylinder partially covered with marine biofouling with various coverage ratios. The elastically mounted cylinder model is partially covered with real moss, which extends from the bottom to top at uniform intervals. The two-degree-of-freedom (2-DOF) vibration and the wake characteristics of the
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Investigation on heat and mass transfer characteristics of a near-wall multi-cycle cavitation bubble and its thermal effects on the wall using an improved compressible multiphase model Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Lei Tian, Yongxue Zhang, Jianyong Yin, Liang Lv, Jinya Zhang, Jianjun Zhu
A cavitation bubble undergoing multi-cycle oscillation with heat and mass transfer is crucial to ships and pumps due to its potential damage. To better understand the mechanism of the heat and mass transfer and the potential damage during the bubble oscillation, a compressible multiphase model that incorporates phase-change, thermal effect, and non-condensable gas advection and diffusion, is developed
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Review of wave attenuation by artificial oyster reefs based on experimental analysis Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Wei Xu, Aifeng Tao, Risheng Wang, Shufang Qin, Jun Fan, Jinyang Xing, Fei Wang, Gang Wang, Jinhai Zheng
In recent years, soft engineering coastal protection based on oyster reefs has emerged as a sustainable solution. However, the mechanism and quantification of wave attenuation by oyster reefs remain unclear. This review briefly presents the development process of wave attenuation by artificial oyster reefs in experiments, with the aim of providing a basis and reference for future studies and projects
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Power-characterized shipboard hybrid energy storage system management for dynamic positioning Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Yingbing Luo, Sidun Fang, Tao Niu, Guanhong Chen, Ruijin Liao
A dynamic positioning (DP) system can flexibly control the azimuth and thrust of propellers to resist very uncertain marine environmental disturbances; the resulting electric power fluctuations are eventually shared by coordinating the shipboard main engines and HESSs. However, excessive power demands may jeopardize battery health due to its power characteristics, even causing a power deficiency in
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Guided wave propagation in debonding detection in CFRP-reinforced steel plate-like structures Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Beata Zima, Łukasz Breńkacz
The present study investigates the guided wave propagation in multilayered steel specimens reinforced with carbon fiber reinforced polymer (CFRP) through theoretical, numerical, and experimental means. The effectiveness of externally bonded reinforcement (EBR) relies heavily on the bonding quality between the CFRP and the substrate. Premature debonding, a prevalent and hazardous defect, can arise from
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A critical survey of power take-off systems based wave energy converters: Summaries, advances, and perspectives Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Bo Yang, Jinhang Duan, Yong Chen, Shaocong Wu, Miwei Li, Pulin Cao, Lin Jiang
Being one of the most promising renewable energy sources, ocean wave energy (OWE) demonstrates considerable development and application potential. Consequently, various related technologies have rapidly advanced in recent decades, particularly in the field of wave energy converters (WEC). Power take-off (PTO) stands as a vital element within WEC systems. During the planning and implementation of WEC
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Experimental study on scouring by submerged pulsed waterjet vertically impinging on cohesive bed Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Chao Feng, Lingrong Kong, Yu Wang, Jiaxing Lu
To enhance the efficiency of marine structure installation and river dredging projects, meeting elevated standards, an experimental investigation on the vertical submerged pulsed waterjet scouring cohesive beds was conducted. This study involved the design of a specialized experimental apparatus and the exploration of various factors influencing scour performance. Employing different proportions of
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Optimal multiple tuned mass dampers for monopile supported offshore wind turbines using Genetic Algorithm Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Somya Ranjan Patro, Susmita Panda, G.V. Ramana, Arnab Banerjee
This study investigates the parametric optimization of multiple-tuned mass dampers (MTMDs) deployed along the length of a tower and monopile structure subjected to stochastic wind and wave forces. The structural components, comprising the tower and monopile, are conceptualized as Euler–Bernoulli beams. The interaction with the soil is modeled through viscoelastic springs distributed along the monopile
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Multi-state ship traffic flow analysis using data-driven method and visibility graph Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Zhongyi Sui, Shuaian Wang, Yuanqiao Wen, Xiaodong Cheng, Gerasimos Theotokatos
Ship traffic flow characteristics play a crucial role in enhancing the effectiveness and efficiency of intelligent maritime traffic management systems. The primary objective of this study is to establish a comprehensive framework for analyzing multi-state traffic flow based on the automatic identification system (AIS). The collected AIS data undergoes preprocessing to calculate traffic flow density
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Parallel path following control of cyber-physical maritime autonomous surface ships based on deep neural predictor Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Lingfeng Li, Anqing Wang, Bing Han, Dan Wang, Tieshan Li, Zhouhua Peng
Unlike the traditional path following being lack of virtual-reality interaction, this paper investigates the parallel path following control problem of cyber–physical maritime autonomous surface ships. By integrating an artificial system, computational experiments, and parallel execution, a parallel path following control method is proposed to achieve the interaction between virtual space and real
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Effect of fin width on torpedo anchor penetration and pullout using model tests with transparent soils Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Abdelaziz Ads, Magued Iskander, Stephan Bless, Mehdi Omidvar
Torpedo anchors are increasingly popular for tethering of offshore structures. Using fins improves their directional stability during penetration, however, fins’ shape affects both penetration depth and pullout capacity. Experiments were carried out to investigate the effect of the width of fins on the behavior of torpedo anchors during penetration and extraction. Four torpedo models having the same
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Parameter fine-tuning method for MMG model using real-scale ship data Ocean Eng. (IF 5.0) Pub Date : 2024-03-01 Rin Suyama, Rintaro Matsushita, Ryo Kakuta, Kouki Wakita, Atsuo Maki
In this paper, a fine-tuning method of the parameters in the MMG model for the real-scale ship is proposed. In the proposed method, all of the arbitrarily indicated target parameters of the MMG model are tuned simultaneously in the framework of SI using time series data of real-sale ship maneuvering motion data to steadily improve the accuracy of the MMG model. Parameter tuning is formulated as a minimization
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Experimental investigation of the influence of micro vortex generator on the bubble cavitation around a hydrofoil Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Jie Chen, Mengjie Zhang, Taotao Liu, Biao Huang, Yong Wang, Changli Hu
The objective of the present paper is to investigate the effect of micro vortex generator (mVG) on the travelling bubble cavitation. The mVG are mounted at two different locations on the leading edge of the NACA 66 hydrofoil. The structural parameters of mVG-1 are the same as those of mVG-2, but it is closer to the leading edge of hydrofoil. A high-speed camera is employed to capture the transient
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Influence of bounding surface plasticity-based soil-structure interaction model on integrated dynamic behaviour of jacket offshore wind turbines Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Mengtao Xu, Lizhong Wang, Lilin Wang, Zhen Guo, Wenjie Zhou
The increasing mean sea depths have necessitated wind turbine foundation to have larger moment resistance capacity, from early design of monopiles to recent piled jackets. Design-oriented pile-soil interaction model (API model) is modified for cyclic loading with a simple correction factor, with little attention paid to stiffness degradation and displacement accumulation caused by cyclic shakedown
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Algorithms for dynamic control of a deep-sea mining vehicle based on deep reinforcement learning Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Qihang Chen, Jianmin Yang, Wenhua Zhao, Longbin Tao, Jinghang Mao, Zhiyuan Li
Deep-sea mining aims to extract mineral resources from the ocean seabed, necessitating advanced vehicles for efficient operations. These vehicles, essential for exploiting the vast underwater resources, require sophisticated navigation. The primary challenge in deep-sea navigation is the absence of satisfactory algorithms that are capable of handling the complexity and unpredictability in deep-sea
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Fully-Coupled cyclic time-history analyses of monopile foundations in sand Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Yannis K. Chaloulos, Panagiota Tasiopoulou, Amalia Giannakou, Jacob Chacko, Amin Aghakouchak, Themis Stergiou
The paper presents the results of 3D coupled cyclic time history numerical analyses of a monopile supporting a 12 MW Offshore Wind Turbine, installed in dense cohesionless soils and subjected to a 600-s load history corresponding to the high phase of a 35-h design storm. The goal of the study is to investigate the governing mechanisms and gauge potential conservatisms or uncertainties in approaches
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Physical model embedding-based generative adversarial networks for unsupervised fault detection of underwater thrusters Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Shuang Gao, Ze Yu, Zhiyao Zhang, Chen Feng, Tianhong Yan, Bo He, Enrico Zio
This paper proposes a hybrid approach incorporating a physical model into generative adversarial networks for unsupervised fault detection of underwater thrusters. Specifically, a thruster physical model with unknown coefficients is constructed according to the thruster speed and the motion state of the vehicle, and this physical model is used to replace the neural network to build the generator. Interpretable
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Evaluation of the influence of dissolved nitrates on corrosion behaviour of ship structural steel exposed to seawater environment Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Muntazir Abbas, Syed Haider Mehdi Rizvi, Shoaib Sarfraz, Asif Raza, Asif Khan, Adil Loya, Antash Najib
Corrosion rates in marine structural steels differ significantly with the varying compositions of seawater particularly near harbours or coastal regions primarily due to the presence of untreated chemically active species from various sources. The reviewed literature reports accelerated steel corrosion losses in coastal seawater exposure conditions, which has widely been attributed to the presence
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Hydrodynamic analysis of an H-shaped pile-restrained floating breakwater combined with a pair of vertical barriers Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Aparna Panda, D. Karmakar, Manu Rao
The present study analyses the performance of a composite breakwater consisting of an H-shaped breakwater attached with vertical/inclined barriers held from both sides using the Multi-Domain Boundary Element Method (MDBEM). The study is performed to analyse the wave transformation characteristics (reflection and transmission), wave energy dissipation and horizontal wave forces due to the gravity wave-structure
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Uncertain surface vessels tracking control based on linear active disturbance rejection control and finite time convergence Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Shuai Cui, Tong Zhao
A joint control scheme based on linear active disturbance rejection control (LADRC) and incorporating finite time control (FTC) and adaptive control (APC) is proposed to address the difficulty of controlling uncertain surface vessels (USV) under enhanced sea conditions. This joint controller combines the advantages of three control algorithms. Firstly, a new finite time linear extended state observer
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Quantification of numerical uncertainties of CFD-predicted wind turbine performance with overset grids Ocean Eng. (IF 5.0) Pub Date : 2024-02-29 Maokun Ye, Yan Zhao, Hamn-Ching Chen, Decheng Wan
The overset-grid technique is supposed to be the most theoretically correct and powerful approach to be used in the Computational Fluid Dynamics (CFD) simulations of wind turbines. The results obtained by CFD simulations which leverage the overset-grid technique could be sensitive to many numerical configurations, e.g., grid spacing, time increment, and turbulence models, etc. As a result, it is important
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Robust fault-tolerant control for dynamic positioning of ships with prescribed performance Ocean Eng. (IF 5.0) Pub Date : 2024-02-28 Heng Li, Xiaogong Lin
This study presents a new fault-tolerant control scheme for ship dynamic positioning. The scheme aims to handle unknown disturbances, imprecise fault estimation, and control input constraints. First, an adaptive sliding mode disturbance observer is introduced. This observer effectively reconstructs disturbances in finite time, even without knowledge of their derivative upper bounds. Next, we design
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Hybrid path planning method for USV using bidirectional A* and improved DWA considering the manoeuvrability and COLREGs Ocean Eng. (IF 5.0) Pub Date : 2024-02-28 Donghao Xu, Jie Yang, Xueqian Zhou, Haitong Xu
This paper proposes a hybrid dynamic path planning algorithm that integrates global path planning (GPP) and local path planning (LPP). The objective is to effectively address the challenges associated with path planning and collision avoidance for unmanned surface vehicles (USV) in complex environments. The bidirectional A* algorithm is used to search the optimized strategy based on the actual geographical
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A novel BACG inverse reliability algorithm for efficient and robust reliability-based topology optimization of marine structures Ocean Eng. (IF 5.0) Pub Date : 2024-02-28 Yupeng Cui, Baolei Zhang, Yang Yu, Siyuan Cheng, Mingxiu Wei, Zihang Jin, Lin Song
Reliability assessment (RA) is pivotal to enhancing the efficiency and robustness of reliability-based optimization. Classical RA algorithms suffer from inefficiency and non-convergence problems such as bifurcation, periodic oscillations, and chaos. In this paper, a bi-directional adaptive conjugate gradient (BACG) algorithm incorporating a newly developed concave vs. convex decision criterion (CCDC)
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Robust path following on rivers using bootstrapped reinforcement learning Ocean Eng. (IF 5.0) Pub Date : 2024-02-28 Niklas Paulig, Ostap Okhrin
This paper develops a Deep Reinforcement Learning (DRL)-based approach for the navigation and control of autonomous surface vessels (ASVs) on inland waterways, where spatial constraints and environmental challenges such as high flow velocities and shallow banks require precise maneuvering. By implementing a state-of-the-art bootstrapped deep Q-learning (DQN) algorithm alongside a novel, flexible training
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Comparative analysis of load reduction device stiffness curves for floating offshore wind moorings Ocean Eng. (IF 5.0) Pub Date : 2024-02-28 Oscar Festa, Susan Gourvenec, Adam Sobey
Traditional mooring systems can be unsuitable and uneconomical for floating offshore wind turbines. Load reduction devices, which are extensible components installed along mooring lines, have been shown to reduce loads on anchors and mooring lines. This enables the use of smaller and lighter anchors and mooring components and reduces fatigue damage on the mooring system. Load reduction devices come
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Robust adaptive saturation-tolerance control for USVs formation via a novel L1-VS guidance Ocean Eng. (IF 5.0) Pub Date : 2024-02-28 Guoqing Zhang, Wenzheng Bian, Xianku Zhang, Jiqiang Li
This paper proposes a saturation-tolerance control algorithm for the limited behavioral capability of actuators, particularly when facing external disturbances in the formation control of underactuated surface vehicles (USVs). An auxiliary subsystem that takes into account saturation-tolerant behavioral boundaries is included, which performs comprehensive compensatory control in the presence of input