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船舶结构运行模态参数辨识研究(英文)

船舶力学 2011年第3期15卷 313-324页

作者：姜大正洪明周力大连理工大学工业装备结构分析国家重点实验室运载工程与力学学部船舶工程学院辽宁大连116024

运行模态分析是仅基于结构运行状态下的响应来提取结构模态参数的一种方法,通常假设环境激励为白噪声进行分析。实际上,船舶航行过程所受激励十分复杂,不能简单地假设为白噪声激励,由主机和螺旋桨等产生的确定频率激励同样存在。因此,... 详细信息

运行模态分析是仅基于结构运行状态下的响应来提取结构模态参数的一种方法,通常假设环境激励为白噪声进行分析。实际上,船舶航行过程所受激励十分复杂,不能简单地假设为白噪声激励,由主机和螺旋桨等产生的确定频率激励同样存在。因此,航行中船舶所受激励可以假设为白噪声和简谐激励同时存在。进一步讨论了运行模态技术在船舶结构振动分析中应用的可行性和前景。研究使用带阻数字滤波技术滤除激励中的简谐成分来提高结构真实模态的辨识精度。讨论了自互功率谱密度法,并研究使用此方法提取同时受白噪声和简谐激励作用的简支梁的模态参数。实验结果表明该方法能够较准确地识别出同时受白噪声和简谐激励的结构模态参数。这对于分析航行中船舶有害振动结构的模态特征,并实施有效的减振优化措施具有很广泛的实际意义。

关键词：运行模态分析船舶结构参数辨识带阻滤波

In situ synergistic strategy of sacrificial intermedium for scalablemanufactured and controllable layered double hydroxide film

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Science China Materials 2022年第7期65卷 1842-1852页

作者： Yi-Xing Zhu Guang-Ling Song da-jiang zheng Maria Serdechnova Carsten Blawert Mikhail L.Zheludkevich Center for Marine Materials Corrosion and Protection College of MaterialsXiamen UniversityXiamen 361005China Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Strasse 121502 GeesthachtGermany State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen 518055China School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQueensland 4072Australia Institute of Materials Science Faculty of EngineeringKiel UniversityKiel 24143Germany

Layered double hydroxides(LDHs),a class of two-dimensional(2D)brucite-like layers,have been effectively applied in diverse ***,the current synthesis methods restrict the in situ scaling-up and tunable production of LDH-based *** by the growing characteristic of“Bryophyllum pinnatum”,a sacrificial co-sputtered Zn-Al transition layer was introduced for the first time to in situ grow a scalable-manufactured and thickness-controllable LDH film on arbitrary substrate materials with flexible shapes through“partial dissolution”and“solution infiltration”*** LDH films could be tailored by the creative regulation of the component,structure and surface state of the transition *** showed that the as-prepared LDH film had strong mechanical robustness under harsh abrasion conditions due to its large thickness and multi-level ***,a series of galvanic couple model experiments based on Zn/Al single-metal transition layers were designed to solve the real-time monitoring issue in the complex hydrothermal *** work not only develops a new strategy to design and grow in situ LDH films with multifaceted features,but also reveals sophisticated LDH formation ***,the findings of this study may broaden the practical application of LDH-based materials toward advanced and smart devices.

关键词： sacrificial transition layer Zn-Al LDH film conversion mechanism solution infiltration controllable growth

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舰船横摇纵摇耦合运动的亚谐共振分析

天津大学学报（自然科学与工程技术版） 2003年第2期36卷 183-186页

作者：唐友刚姜大宁郑宏宇郑俊武天津大学建筑工程学院天津300072

舰船运动的阻尼和刚度非线性,导致舰船大幅运动时横摇和纵摇之间的耦合.该文根据舰船纵摇与横摇耦合的非线性运动方程,考虑强海浪激励以及纵摇和横摇频率为2∶1的内共振关系,采用非线性动力学中多尺度方法,求出横摇和纵摇运动的摄动解,... 详细信息

舰船运动的阻尼和刚度非线性,导致舰船大幅运动时横摇和纵摇之间的耦合.该文根据舰船纵摇与横摇耦合的非线性运动方程,考虑强海浪激励以及纵摇和横摇频率为2∶1的内共振关系,采用非线性动力学中多尺度方法,求出横摇和纵摇运动的摄动解,研究了亚谐共振发生的条件,揭示了亚谐共振状态下舰船横摇-纵摇运动的动力学特征.研究表明,舰船亚谐共振的发生取决于波浪遭遇频率和纵摇频率的比值以及波浪激励的大小;舰船运动发生亚谐共振时,舰船出现大幅运动甚至倾覆.

关键词：舰船倾覆舰船非线性运动纵摇-横摇耦合亚谐共振

Cascade degradation and electrocatalytic upcycling of waste poly(ethylene terephthalate)to valued products

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Nano Research 2025年第1期18卷 76-93页

作者： Xin Li Zirui jiang Zongkui Kou John Wang Shiyou zheng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Department of Materials Science and Engineering National University of SingaporeSingapore 117574Singapore

The global annual production of poly(ethylene terephthalate)(PET)has reached 82 million tons,yet only a small fraction(less than 20%)is *** ultra-slow degradation rate of PET results in the accumulation of PET waste in the environment,causing serious plastic pollution and posing severe challenges to *** response,great efforts have been directed toward developing a cascade degradation and electrocatalytic upcycling strategy,which serves as a“waste-towealth”*** strategy involves electro-reforming PEThydrolyzed intermediates or using PET pyrolyzed products as electrocatalysts to generate high-value *** review provides an overview of the state-of-the-art strategies for the“degradation-electrocatalytic upcycling(De-eUp)”of PET ***,an introduction to the strategy is provided,categorizing it into two main frameworks:“pyrolysis-electrocatalytic upcycling”and“hydrolysis-electrocatalytic upcycling”.The section on“pyrolysis-electrocatalytic upcycling”delves into the degradation methods for designing derived carbon nanomaterials and their utilization as high-performance ***“hydrolysis-electrocatalytic upcycling”section discusses recent advancements in electro-reforming of PET hydrolyzed intermediates for the production of C_(1) and C_(2) *** review concludes by examining the challenges and future prospects in developing an efficient and economical PET upcycling *** is anticipated that this review will stimulate further progress in plastic waste valorization.

关键词： poly(ethylene terephthalate)waste electrocatalytic upcycling pyrolysis hydrolysis ethylene glycol oxidation reaction

Surface micro-arrays enhancing electromagnetic interference shielding of polydimethylsiloxane/multiwalled carbon nanotubes nanocomposites

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Nano Research 2025年第1期18卷 508-519页

作者： Ke jiang Zhi Chen Ji Yu Chen zheng Shan Huang Ming Wang Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Mechanics Civil Engineering and ArchitecturesNorthwestern Polytechnical UniversityXi’an 710072China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Herein,the electromagnetic shielding performance of surface concave-convex(SC)and zig-zag micro-arrays was studied by using a simulation prediction and a three-dimensional(3D)printing custom ***,surface stripe concaveconvex(SSC)and surface cylindrical concave-convex(SCC)micro-arrays with or without zig-zag micro-arrays are designed,and their shielding performance is simulated in multi-bands(C-,X-band).The multiwalled carbon nanotubes/polydimethylsiloxane composites(MWCNT/PDMS)with different SC structures and different electrical conductivity are molded in acrylonitrile-butadiene-styrene copolymer(ABS)molds which are printed by a 3D *** results show that the electromagnetic interference shielding effectiveness(EMI SE)of the samples can be enhanced by constructing the SC micro-arrays with zig-zag micro-arrays,and improving with the increase of conductivity and *** addition,the shielding mechanism of the SC-MWCNT/PDMS composites is investigated and discussed by an electromagnetic simulation.

关键词： surface micro-arrays electrical properties electromagnetic interference(EMI)shielding three-dimensional(3D)printing

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng zheng Wang Ruisong Zhu Ruijie Liu jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

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六自由度并联机构的控制系统及仿真试验探究

组合机床与自动化加工技术 2016年第9期 43-46页

作者：姜昆鹏陈敏丁建军蒋大伟郑刚江苏大学机械工程学院江苏镇江212013 中船重工第704研究所上海200000

对六自由度并联机构液压系统主要的动力执行机构进行数学模型的建立以及稳定性简要分析,以满足六自由度并联机构中六个独立的单缸伸缩机构在速度、位移及加速度等运动指标的要求;文章在进行三维建模后按田间路谱信息的要求运用AdaMS对... 详细信息

对六自由度并联机构液压系统主要的动力执行机构进行数学模型的建立以及稳定性简要分析,以满足六自由度并联机构中六个独立的单缸伸缩机构在速度、位移及加速度等运动指标的要求;文章在进行三维建模后按田间路谱信息的要求运用AdaMS对并联机构整体进行运动模拟仿真;考虑到系统中的伺服阀误差分析,针对仿真得到的结果选取一驱动函数在AMESIM建立的系统中变化伺服阀前置放大级与PID控制共同调节系统误差,实现与所选取的驱动函数准确跟随。

关键词：液压系统数学模型误差分析仿真探究

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong zheng Jialin Chen Jinghong Xu Bin jiang Lei Li Yawei Li Yuliang dai Bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

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运行模态分析技术在船舶结构振动中的应用

中国舰船研究 2010年第3期5卷 22-26,33页

作者：姜大正洪明周力大连理工大学运载工程与力学学部船舶工程学院辽宁大连116024 大连理工大学工业装备结构分析国家重点实验室辽宁大连116024

运行模态分析是一种仅基于环境激励下结构的响应来提取模态参数的方法,通常假设环境激励为白噪声进行分析。实际上,船舶航行过程中所受激励十分复杂,除受海浪等随机激励外,还受到来自螺旋桨、主机等确定的单频激励。因此航行中的船舶所... 详细信息

运行模态分析是一种仅基于环境激励下结构的响应来提取模态参数的方法,通常假设环境激励为白噪声进行分析。实际上,船舶航行过程中所受激励十分复杂,除受海浪等随机激励外,还受到来自螺旋桨、主机等确定的单频激励。因此航行中的船舶所受激励应假设为白噪声和确定频率的激励同时存在。讨论运行模态分析方法在船舶结构中应用的可行性;在白噪声激励假设下,提出使用自互谱密度法来进行结构模态参数识别,并用简支梁实验对上述方法进行验证。最后将该方法运用于对某船航行中桅杆的振动响应数据进行分析和讨论。

关键词：运行模态分析结构振动参数辨识结构