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On the two-layer high-level Green-Naghdi model in a general form

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Journal of Hydrodynamics 2024年第1期36卷 78-86页

作者： Bin-bin Zhao Tian-yu Zhang Zhan Wang wen-yang duan Alexander Chesnokov Natalia Shmakova College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China Qingdao Innovation and Development Center of Harbin Engineering University Qingdao266000China Lavrentyev Institute of Hydrodynamics NovosibirskRussia

The traditional high-level Green-Naghdi(HLGN)model,which uses the polynomial as the shape function to approximate the variation of the horizontal-and vertical-velocity components along the vertical direction for each-fluid layer,can accurately describe the large-amplitude internal waves in a two-layer system for the shallow configuration(h_(2)/λ■1,h_(1)/λ■1).However,for the cases of the deep configuration(h_(2)/λ■1,h_(1)/λ=O(1)),higher-order polynomial is needed to approximate the variation of the velocity components along the vertical direction for the lower-fluid ***,however,introduces additional unknowns,leading to a significant increase in computational *** paper,for the first time,derives a general form of the HLGN model for a two-layer fluid system,where the general form of the shape function is used during the *** obtaining the general form of the two-layer HLGN equations,corresponding solutions can be obtained by determining the reasonable shape ***-amplitude internal solitary waves in a deep configuration are studied by use of two different HLGN *** of the two HLGN models shows that the polynomial as the shape function for the upper-fluid layer and the production of exponential and polynomial as the shape function for the lower-fluid layer is a good *** comparing with Euler’s solutions and the laboratory measurements,the accuracy of the two-layer HLGN model is verified.

关键词： High-level Green-Naghdi(HLGN)model general form internal waves deep configuration

On solitary wave in nonuniform shear currents

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Journal of Hydrodynamics 2020年第4期32卷 800-805页

作者： Zhan Wang Bin-bin Zhao wen-yang duan R.Cengiz Ertekin Masoud Hayatdavoodi Tian-yu Zhang College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Department of Ocean and Resources Engineering University of HawaiiHonoluluUSA Civil Engineering Department School of Science and EngineeringUniversity of DundeeDundeeUK

In this paper,steady solutions of solitary waves in the presence of nonuniform shear currents are obtained by use of the high-level Green-Naghdi(HLGN)*** focus on large-amplitude solitary waves in strong opposing shear *** linear-type currents,quadratic-type currents and cubic-type currents are *** particular,the wave speed,wave profile,velocity field,particle trajectories and vorticity distribution are *** is demonstrated that presence of the nonuniform shear current modifies the velocity field and vorticity field of the solitary wave.

关键词： Solitary wave nonuniform shear current velocity field particle trajectories vorticity field

Prediction of added resistance of a ship in waves at low speed

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Journal of Hydrodynamics 2019年第6期31卷 1231-1239页

作者： Feng Diao Ji-kang Chen wen-yang duan Wei-xin Zhou Jingpu Chen Jin-fang Wei China Ship Scientific Research Center Wuxi 214082China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

This paper presents predictions of the added resistance of a ship in waves at a low speed according to the IMO minimum propulsion power requirement by a hybrid Taylor expansion boundary element method(TEBEM).The flow domain is divided into two parts:the inner domain and the outer *** first-order TEBEM with a simple Green function is used for the solution in the inner domain and the zero order TEBEM with a transient free surface Green function is used for the solution in the outer *** TEBEM is applied in the numerical prediction of the motions and the added resistance in waves for three new designed commercial *** numerical results are compared with those obtained from the seakeeping model *** is shown that the prediction of the ship motions and the added resistance in waves are in good agreement with the experimental *** comparison also indicates that the accuracy of the motion estimation is crucial for the prediction of the wave added *** general,the TEBEM enjoys a satisfactory accuracy and efficiency to predict the added resistance in waves at a low speed according to the IMO minimum propulsion power requirement.

关键词： Taylor expansion boundary element method(TEBEM) added resistance in waves low speed minimum propulsion power

一种用于船舶纵-横联合减摇的预测控制器（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第5期17卷 399-415页

作者： wen-yang duan yang HAN Rui-feng WANG Li-min HUANG Department of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China Huhhot Railway Bureau Huhhot 010000 China

目的:为提高船舶运动联合减摇效果,提出一种基于船舶运动及船舶水动力预报的联合减摇控制方法,并基于弱非线性二维半方法进行数值仿真,分析该控制方法的减摇控制效果。创新点:1.提出基于船舶运动预报和水动力预报的减摇方法,克服了控制... 详细信息

目的:为提高船舶运动联合减摇效果,提出一种基于船舶运动及船舶水动力预报的联合减摇控制方法,并基于弱非线性二维半方法进行数值仿真,分析该控制方法的减摇控制效果。创新点:1.提出基于船舶运动预报和水动力预报的减摇方法,克服了控制时延对减摇效果的影响;2.基于弱非线性二维半方法进行船舶运动减摇数值仿真,验证了该方法能够实现良好的联合减摇控制效果。方法:1.在控制过程中基于极短期预报方法预报船舶运动姿态,并利用船舶运动方程预报水动力,将预报的水动力作为鳍角分配的依据;2.基于弱非线性二维半方法在时域内进行船舶运动减摇数值仿真,分析该控制方法在各种不同海况下的减摇控制效果。结论:1.弱非线性二维半方法在高速船舶的水动力预报中可以获得良好的效果;2.在各个不同海况下,本文提出的控制方法能够实现有效的联合减摇。

关键词：主动鳍联合减摇预测控制器船舶运动和水动力预报控制器

一种用于非线性非平稳波浪极短期预报的复合经验模态分解自回归模型（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第2期17卷 115-129页

作者： wen-yang duan Li-min HUANG yang HAN De-tai HUANG Department of Shipbuilding Engineering Harbin Engineering University

目的:相对于由能量平衡方程得到的数值预报模型和以神经网络为代表的非线性模型而言,自回归(AR)模型在波浪预报中具有计算效率高、自适应性强和建模所需的样本小等优点,但同时存在局限于平稳线性假设的缺陷。针对非线性非平稳波浪的极... 详细信息

目的:相对于由能量平衡方程得到的数值预报模型和以神经网络为代表的非线性模型而言,自回归(AR)模型在波浪预报中具有计算效率高、自适应性强和建模所需的样本小等优点,但同时存在局限于平稳线性假设的缺陷。针对非线性非平稳波浪的极短期预报问题,提出一种复合的经验模态分解自回归预报模型,提高波浪预报精度。创新点:1.研究非线性非平稳波浪极短期预报问题,提出一种复合的预报方法;2.基于三个不同地理位置的海洋波浪实测数据对预测模型进行验证,并分析非线性非平稳性对波浪预报结果的影响。方法:1.在AR模型中引入经验模态分解(EMD)方法,形成复合的EMD-AR预报模型;2.分析实测波浪数据的非线性和非平稳性特点,并基于实测波浪数据获得AR模型和EMD-AR模型的预报结果;3.基于多种预报误差度量分析AR模型和EMD-AR模型的预报性能以及非线性非平稳性对波浪预报结果的影响。结论:1.波浪非线性和非平稳性会导致AR预报模型精度降低。预报误差中,幅值上的偏差主要由波浪的非线性引起,而相位上的偏差则是源于波浪的非平稳性;***方法能够有效地克服波浪非线性和非平稳性对AR模型在精度上所带来的不良影响,在精度上EMD-AR模型的预报结果较AR模型有较大提高。

关键词：波浪预报非线性和非平稳性自回归模型经验模态分解经验模态分解自回归模型

用于非线性非平稳船舶运动极短期预报的一种复合自回归经验模态分解支持向量机回归模型（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第7期16卷 562-576页

作者： wen-yang duan Li-min HUANG yang HAN Ya-hui ZHANG Shuo HUANG Department of Shipbuilding Engineering Harbin Engineering University Key Laboratory of Renewable Energy Chinese Academy Science

目的:基于支持向量机回归(SVR)模型在非线时间序列的预测能力及经验模态分解(EMD)方法在处理非线性非平稳性的优势,提出一种复合自回归经验模态分解支持向量机回归(AR-EMDSVR)模型,提高非线性非平稳船舶运动极短期预报精度。创新点:1.... 详细信息

目的:基于支持向量机回归(SVR)模型在非线时间序列的预测能力及经验模态分解(EMD)方法在处理非线性非平稳性的优势,提出一种复合自回归经验模态分解支持向量机回归(AR-EMDSVR)模型,提高非线性非平稳船舶运动极短期预报精度。创新点:1.研究非线性非平稳船舶运动的极短期预报问题,提出一种复合的预报方法;2.基于不同层次的预报模型和模型试验数据,分析非线性非平稳性对极短期预报精度的影响。方法:1.在SVR模型中引入基于自回归(AR)预报端点延拓的EMD方法,形成复合的AR-EMDSVR预报模型;2.基于集装箱船模水池试验运动数据将AR-EMD-SVR模型与AR、SVR和EMD-AR三种模型进行比较,分析非线性非平稳性对极短期预报的影响以及不同模型的预报性能。结论:***-EMD方法能够有效的克服非平稳对极短期预报模型(AR和SVR)在精度上所带来的不良影响;2.基于船模试验数据的预报结果表明:相较于AR、SVR和EMD-AR三种预报模型,基于AR-EMD-SVR模型的非线性非平稳船舶运动极短期预报结果具有更高的精度。

关键词：非线性非平稳船舶运动极短期预报经验模态分解支持向量机回归模型自回归模型

Numerical Simulation of Dam Breaking Using Smoothed Particle Hydrodynamics and Viscosity Behavior

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Journal of Marine Science and Application 2010年第1期9卷 34-41页

作者：郑兴段文洋 College of Shipbuilding Engineering Harbin Engineering University

Smoothed particle hydrodynamics (SPH) is a Lagrangian meshless particle method. It is one of the best method for simulating violent free surface flows in fluids and solving large fluid deformations. Dam breaking is a typical example of these problems. The basis of SPH was reviewed, including some techniques for governing equation resolution, such as the stepping method and the boundary handling method. Then numerical results of a dam breaking simulation were discussed, and the benefits of concepts like artificial viscosity and position correction were analyzed in detail. When compared with dam breaking simulated by the volume of fluid (VOF) method, the wave profile generated by SPH had good agreement, but the pressure had only reasonable agreement. Improving pressure results is clearly an important next step for research.

关键词： meshless method smoothed particle hydrodynamics (SPH) dam breaking free surface flow

Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex

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Neural Regeneration Research 2025年第10期20卷 2923-2937页

作者： Yan Li Peng Hao Hongmei duan Fei Hao wen Zhao Yudan Gao Zhaoyang yang Kwok-Fai So Xiaoguang Li Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina China Rehabilitation Science Institute China Rehabilitation Research CenterBeijing Key Laboratory of Neural Injury and RehabilitationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Engineering MedicineBeihang UniversityBeijingChina Guangdong-HongKong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint LaboratoryJinan UniversityGuangzhouGuangdong ProvinceChina Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory) GuangzhouGuangdong ProvinceChina Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongHong Kong Special Administration RegionChina Center for Brain Science and Brain-Inspired Intelligence Guangdong-HongKong-Macao Greater Bay AreaGuangzhouGuangdong ProvinceChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina

The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after ***,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains *** this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic *** findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated ***,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain *** findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.

关键词： adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation

Fully Nonlinear Shallow Water Waves Simulation Using Green-Naghdi Theory

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Journal of Marine Science and Application 2010年第1期9卷 1-7页

作者：赵彬彬段文洋 College of Shipbuilding Engineering Harbin Engineering University

Green-Naghdi （G-N） theory is a fully nonlinear theory for water waves. Some researchers call it a fully nonlinear Boussinesq model. Different degrees of complexity of G-N theory are distinguished by ＂levels＂ where the higher the level, the more complicated and presumably more accurate the theory is. In the research presented here a comparison was made between two different levels of G-N theory, specifically level II and level III G-N restricted theories. A linear analytical solution for level III G-N restricted theory was given. Waves on a planar beach and shoaling waves were both simulated with these two G-N theories. It was shown for the first time that level III G-N restricted theory can also be used to predict fluid velocity in shallow water. A level III G-N restricted theory is recommended instead of a level II G-N restricted theory when simulating fullv nonlinear shallow water waves.

关键词： Green-Naghdi theory Boussinesq model fully nonlinear water waves shoaling waves