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Perturbation Analysis of the Attached Water Mass Effect on Offshore Platform Dynamic Response

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China Ocean Engineering 1993年第4期8卷 369-382页

作者： Chu, Liangcheng Qu, Naisi guo, yonggang Lu, Min Dalian Univ of Technology Dalian China

Theoretically speaking, it is impossible to make the differential equation of motion uncoupled for the natural modes of a system in consideration of the attached water. The hydro-elastic structure is equal to the non-proportional damping system. In this paper a perturbation analysis method is put forward. The structure motion equation is strictly solved mathematically, and the non-proportional damping problem is transformed into a series of proportional damping ones in the superposition form. The paper also presents the calculation formula of the dynamic response of the structure being subjected to harmonic and arbitrary load. The convergence of the proposed method is also studied in this paper, and the corresponding convergence conditions are given. Finally, the proposed method is used to analyze the displacement response of a real offshore platform. The calculation results show that this method has the characteristics of high accuracy and fast convergence.

关键词： Convergence of numerical methods Damping Dynamic response Equations of motion Mathematical models Perturbation techniques Structural analysis Structural loads Water

Stability and a fast calculation method of travel speed of pulse peak in convergence zone

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1274-1282页

作者： REN Yun ZHANG RenHe WANG Jun guo yonggang Luo WenYu State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

A long-range sound propagation experiment was conducted in the West Pacific Ocean in summer *** signals received by a towed array indicate that the travel speed of pulse peak(TSPP)in the convergence zones is ***,an equivalent sound speed can be used at all ranges in the convergence zones.A fast calculation method based on the beam-displace-ment ray-mode(BDRM)theory and convergence zone theory is proposed to calculate this equivalent sound *** computation speed of this proposed method is over 1000 times faster than that of the conventional calculation method based on the normal mode theory,with the computation error less than 0.4%compared with the experimental ***,the effect of frequency and sound speed profile on the TSPP is studied with the conventional and fast calculation methods,showing that the TSPP is almost independent of the frequency and sound speed profile in the ocean surface layer.

关键词： travel speed pulse peak pulse propagation BDRM theory turning point convergence zone

The effects of the ocean surface wave spectrum on low frequency ambient noise in deep water

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Chinese Journal of Acoustics 2019年第1期38卷 35-48页

作者： XU Dong LI Fenghua guo yonggang WANG Yuan State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences Beijing 100190 University of Chinese Academy of Sciences Beijing 100049 State Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sczences Beijing 100190

An ocean surface wave spectrum which is used for low frequency ambient noise in deep water is proposed. It explains the mechanism of low frequency ambient noise from the theoretical relation between the spectrum of sound pressure and wave. Combining the surface wave spectrum and local wind speed in deep water, a theoretical expression of low frequency ambient noise is obtained with wave generated noise theory. Simulation results show that the wave spectrum is crucial to the intensity and the spectral slope of radiated noise spectrum,and the theoretical noise spectrum could be used to predict the ambient noise in deep *** predicting results axe verified through the experimental data recorded by an ocean bottom seismometer that was deployed on the floor of deep water in April 2016. It is observed that the statistical noise levels from the experimental data for frequencies from 1 Hz to 100 Hz are larger than 70 dB, and the low frequency ambient noise spectrum follows the shape of inverted"N",the valley of noise spectrum is at 3-4 Hz, and the noise intensity is 70 dB. The peak of noise spectrum is at 50 Hz, and the noise intensity is 92 dB. The correlation coefficient is 0.95 between the model spectrum and measured data.

关键词： ocean surface wave spectrum low frequency ambient noise deep water

聚苯酯/聚四氟乙烯复合涂层的制备及润湿性能

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高分子材料科学与工程 2016年第1期32卷 89-93,99页

作者：郭永刚河南工业大学机电工程学院河南郑州450007

以聚苯酯和聚四氟乙烯粉末为原料,采用简单的一步成膜法分别制备了纯的聚苯酯(POB)、聚四氟乙烯(PTFE)涂层和聚苯酯/聚四氟乙烯复合涂层。接触角测量仪测量结果表明制备的聚苯酯、聚四氟乙烯涂层的接触角都大于130°,具有疏水性能;而聚... 详细信息

以聚苯酯和聚四氟乙烯粉末为原料,采用简单的一步成膜法分别制备了纯的聚苯酯(POB)、聚四氟乙烯(PTFE)涂层和聚苯酯/聚四氟乙烯复合涂层。接触角测量仪测量结果表明制备的聚苯酯、聚四氟乙烯涂层的接触角都大于130°,具有疏水性能;而聚苯酯/聚四氟乙烯复合涂层接触角都大于150°,具有超疏水性能。扫描电子显微镜测试表明聚苯酯和聚四氟乙烯共混后形成的复合涂层具有微纳米二元复合结构。X射线光电子能谱仪测试结果表明聚苯酯和聚四氟乙烯较好地共存于复合涂层表面,正是由于复合涂层表面的微观形貌和化学成分的共同作用,使其具有了超疏水的性能。文中考察了PTFE与POB质量比对复合涂层润湿性能的影响,结果表明随着PTFE与POB质量比的增加,复合涂层的水接触角先增大后减小,但都大于150°。而水滴的滚动角则呈现相反的变化规律。这种制备聚苯酯/聚四氟乙烯复合涂层的方法简单方便,不需要复杂的实验步骤和昂贵的实验设备,适合于大规模和工业化生产。

关键词：超疏水聚苯酯/聚四氟乙烯复合涂层接触角滚动角润湿性能

Design of multifunctional interfaces on ceramic solid electrolytes for high-performance lithium-air batteries

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Green Energy & Environment 2025年第1期10卷 183-192页

作者： Yunxin Shi Ziyang guo Changhong Wang Mingze Gao Xiaoting Lin Hui Duan yonggang Wang Xueliang Sun College of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot010021China Department of Mechanical and Materials Engineering Western UniversityLondonONN6A 5B9Canada Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Fudan UniversityShanghai200433China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingboZhejiang315100China

High-energy-density lithium(Li)–air cells have been considered a promising energy-storage system,but the liquid electrolyte-related safety and side-reaction problems seriously hinder their *** address these above issues,solid-state Li–air batteries have been widely ***,many commonly-used solid electrolytes generally face huge interface impedance inLi–air cells and also showpoor stability towards ambient air/Li ***,we fabricate a differentiating surface-regulated ceramic-based composite electrolyte(DSCCE)by constructing disparately LiI-containing polymethyl methacrylate(PMMA)coating and Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)layer on both sides of Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)(LAGP).The cathode-friendly LiI/PMMA layer displays excellent stability towards superoxide intermediates and also greatly reduces the decomposition voltage of discharge products in Li–air ***,the anode-friendly PVDF-HFP coating shows low-resistance properties towards ***,Li dendrite/passivation derived from liquid electrolyte-induced side reactions and air/I-attacking can be obviously suppressed by the uniformand compact composite *** a result,the DSCCE-based Li–air batteries possess high capacity/low voltage polarization(11,836mAh g^(-1)/1.45Vunder 500mAg^(-1)),good rate performance(capacity ratio under 1000mAg^(-1)/250mAg^(-1) is 68.2%)and longterm stable cell operation(~300 cycles at 750 mA g^(-1) with 750 mAh g^(-1))in ambient air.

关键词： Li-air batteries Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3) Polymers Composite electrolyte Ambient air

Erratum to:Bio-inspired Filter Design Based on Vortex Control Mechanism of Parallel Groove Structure

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Journal of Bionic Engineering 2024年第3期21卷 1617-1617页

Erratumto:Journal of Bionic Engineering(2023)20:338-348 https:/doi.0rg/10.1007/s42235-022-00247-4 In Table 1,the value of Mesh's Feature dimensions(mm)"0.42"should have read"0.04".The original article has been corrected.

关键词： Vortex dimensions corrected

矿物粉尘环境下矿井缠绕提升钢丝绳振动磨损特性研究

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摩擦学学报（中英文） 2024年第8期44卷 1107-1124页

作者：张庆郭永刚彭玉兴河南工业大学机电工程学院河南郑州450001 中国矿业大学机电工程学院江苏徐州221116 江苏省矿山智能采掘装备协同创新中心(省部共建) 江苏徐州221116

针对矿物粉尘易黏附于具有润滑保护的矿井缠绕提升钢丝绳表面而影响其接触磨损过程问题,利用自制缠绕提升钢丝绳振动磨损测试平台,分析矿井中常见矿物粉尘(煤炭颗粒和矿石颗粒)对缠绕接触钢丝绳间的摩擦学参数演化规律,并揭示其对钢丝... 详细信息

针对矿物粉尘易黏附于具有润滑保护的矿井缠绕提升钢丝绳表面而影响其接触磨损过程问题,利用自制缠绕提升钢丝绳振动磨损测试平台,分析矿井中常见矿物粉尘(煤炭颗粒和矿石颗粒)对缠绕接触钢丝绳间的摩擦学参数演化规律,并揭示其对钢丝绳磨损过程的干扰机制,以期为矿井提升系统的运维及延长钢丝绳使用寿命提供基础数据支撑.结果表明:随着煤炭颗粒体积分数从10%增至40%,钢丝绳在相对稳定阶段的平均摩擦系数从0.158增至0.173,而颗粒尺寸的增大则使其呈现出相反的变化趋势;此外,随着煤炭颗粒体积分数不断增加,钢丝绳磨损表面C元素含量越来越多,黏附效应越来越严重,且剥层现象也越来越明显;随着矿石颗粒体积分数增至40%,钢丝绳摩擦系数增至0.157,磨损深度增至120.4μm,且相比于煤炭颗粒,钢丝绳摩擦系数曲线更加平稳,而颗粒尺寸则与摩擦系数和磨损深度负相关;矿石颗粒浓度的增加及尺寸的减小均导致钢丝绳接触表面磨粒磨损程度更加严重.

关键词：钢丝绳矿物粉尘缠绕接触振动磨损干扰机制

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海底表层声场垂直衰减分析

声学学报 2015年第2期40卷 224-233页

作者：张波李风华郭永刚中国科学院声学研究所声场声信息国家重点实验室北京100190 中国科学院大学北京100049

声波在海底中的传播衰减规律是海洋声学中值得研究的课题。根据简正波理论推导了高声速海底表层声场垂直衰减系数的解析表达式,并给出了其理论上限。数值仿真与实验研究表明:对液态海底模型,海底表层声场垂直衰减系数与声波频率基本呈正... 详细信息

声波在海底中的传播衰减规律是海洋声学中值得研究的课题。根据简正波理论推导了高声速海底表层声场垂直衰减系数的解析表达式,并给出了其理论上限。数值仿真与实验研究表明:对液态海底模型,海底表层声场垂直衰减系数与声波频率基本呈正比;对于特定频率,海水-海底声速比是影响垂直衰减系数的最主要因素,比值越小垂直衰减系数越大;对于斜率较大的楔形海底地形,且声源在深水区、接收点在浅水区的情形,垂直衰减系数会大大小于其理论上限。

关键词：声场特性简正波声波频率特定频率接收点衰减系数楔形数值仿真水听器声强

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大坝强震应急决策支持系统设计与实现

地震工程学报 2024年第5期46卷 1234-1242页

作者：梅文健郭永刚西藏农牧学院水利土木工程学院西藏林芝860000

为提高水库大坝应对强震事件的应急反应能力,减少应急决策的随意性和盲目性,设计并开发一套大坝强震应急决策支持系统。对该系统进行详细的功能需求分析,完成系统整体框架结构的设计,同时对系统的主要功能、系统结构体系、数据库和功能... 详细信息

为提高水库大坝应对强震事件的应急反应能力,减少应急决策的随意性和盲目性,设计并开发一套大坝强震应急决策支持系统。对该系统进行详细的功能需求分析,完成系统整体框架结构的设计,同时对系统的主要功能、系统结构体系、数据库和功能流程等进行深入研究。系统结构的核心包括数据库、模型库、方法库和知识库,采用浏览器/服务器(B/S)架构与客户端/服务器(C/S)架构相结合的模式进行开发,实现了综合信息管理、强震动分析预警、决策支持和应急管理等主要功能。综合信息管理子系统整合了大量有关大坝和地震的信息,为决策提供了丰富的基础数据;强震动分析预警子系统能够实时监测强震信号,对大坝震后可能的危险情况进行预警;决策支持子系统根据预警信息和综合信息,为应急决策提供科学的决策依据;应急管理子系统可以根据决策结果,制定并执行应急响应计划。此外,界面设计简洁直观,易于操作,进一步提升了系统的实用性和用户的使用体验。研究成果可以为大坝强震安全构筑工程安全防护措施外的一道技术防线,有助于降低因大坝强震事件带来的灾害风险,保护水库大坝及下游人民的生命财产安全。

关键词：大坝强震应急决策决策支持系统

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