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A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： Meng LI hu DING Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping *** this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first *** motion differential equations of the VTNES coupled with a linear oscillator(LO)are *** the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified *** this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is *** damping effect and dynamic characteristics of the VTNES are studied theoretically and *** results show that the VTNES has better damping effects when strong modulation responses(SMRs)***,even for small-amplitude vibration,the VTNES also has a good vibration suppression *** sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

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纳米压痕数据分析的混合方法研究

机械强度 2009年第5期31卷 857-860页

作者：蒋锐胡小方许峰伍小平中国科学技术大学中国科学院材料力学行为和设计重点实验室合肥230027

在Oliver-Pharr方法的基础上,提出一种新的纳米压痕数据分析方法称为混和方法。该方法通过量纲分析和理论分析,得到压痕过程中相关物理量之间的线性关系,在此基础上通过分析整个加卸载曲线,可实现从少量的压痕试验计算得到随压入深度连... 详细信息

在Oliver-Pharr方法的基础上,提出一种新的纳米压痕数据分析方法称为混和方法。该方法通过量纲分析和理论分析,得到压痕过程中相关物理量之间的线性关系,在此基础上通过分析整个加卸载曲线,可实现从少量的压痕试验计算得到随压入深度连续变化的硬度和弹性模量。实验研究验证线性关系是正确的,混合方法是可靠的。

关键词：纳米压痕量纲分析接触刚度

Near-Field Heat Transfer Enhancement of SiC-hBN-InSb Thermophotovoltaic System by Graphene Strong Coupling Effects

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Journal of Thermal Science 2024年第4期33卷 1409-1420页

作者： XU Zhiguo hu Zhifang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China

Near-field thermophotovoltaic(NTPV)devices comprising a SiC-hBN-graphene emitter and a graphene-InSb cell with gratings are designed to enhance the performance of the NTPV *** electrodynamics and rigorous coupled-wave analysis are employed to calculate radiative heat transfer *** is found that the NTPV systems with two graphene ribbons perform better due to the graphene strong coupling *** effects of graphene chemical potential are *** is demonstrated that near-field radiative heat transfer of thermophotovoltaic devices is enhanced by the coupling of surface plasmon polaritons,surface phonon polaritons,hyperbolic phonon polaritons,and magnetic polaritons caused by the graphene strong coupling *** splitting frequency of different polaritons is calculated to quantify the mutual interaction of graphene strong coupling ***,the effects of cell grating filling ratio are *** excitation of magnetic polaritons is affected by the graphene ribbon and the cell filling *** investigation provides a new explanation of the enhancement mechanism of graphene-assisted thermophotovoltaic systems and a novel approach for improving the output power of the near-field thermophotovoltaic system.

关键词： near-field radiative heat transfer thermophotovoltaics strong coupling effect multiple magnetic polaritons graphene-hbn heterostructures

Distributed Fault-Tolerant Control of Uncertain Multi-Agent Systems with Connectivity Maintenance

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Journal of Systems Science & Complexity 2024年第1期37卷 40-62页

作者： XING Xueyan hu Guoqiang Continental-NTU Corporate Lab Nanyang Technological UniversitySingapore 639798Singapore Continental-NTU Corporate Lab and the School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

In this paper,a distributed cooperative control protocol is presented to deal with actuator failures of multi-agent systems in the presence of connectivity *** the developed strategy,each agent can track the reference trajectory of the leader in the presence of actuator failures,disturbances and *** connectivity of the multi-agent system can always be ensured during the control *** achieve the aforementioned control objectives,a potential function is introduced to the distributed adaptive fault-tolerant control algorithm to preserve the initial connected network among the *** uncertainty of the multi-agent system,which is allowed to be described by discontinuous functions,is approximated and compensated using the fuzzy logic *** asymptotic stability of the closed-loop system is demonstrated through the use of Cellina’s approximate selection theorem of nonsmooth *** to the developed adaptive laws,the upper bound of the disturbance is allowed to be uncertain,which facilitates the implementation of the control ***,simulation results are provided to verify the effectiveness of the proposed control scheme.

关键词： Actuator failure connectivity maintenance coordination control uncertainties

Enhancing adhesive bond strength of CFRP/titanium joints through NaOH anodising and resin pre-coating treatments with optimised anodising conditions

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Chinese Journal of Aeronautics 2024年第2期37卷 511-523页

作者： Yunsen hu Jingheng ZHANG Lin WANG Fei CHENG Xiaozhi hu School of Materials and Chemistry Southwest University of Science and TechnologyMianyang 621000China School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Engineering Research Center of Biomass Materials Ministry of EducationSouthwest University of Science and TechnologyMianyang 621010China Department of Mechanical Engineering University of Western AustraliaPerthWA 6009Australia

Adhesively Bonded Carbon Fibre Reinforced Plastic(CFRP)and titanium alloy have been extensively used as a hybrid structure in modern aircrafts due to their excellent combination of mechanical properties and chemical *** study utilised NaOH anodising method to create micro-rough titanium surfaces for enhancing adhesive bonding between titanium alloy and CFRP laminates.A special and simple technique named Resin Pre-Coating(RPC)was also employed to improve the surface wetting of anodised titanium and grinded CFRP *** influences of anodising temperature and duration on the surface morphology,wettability and adhesive bond strength were *** single lap shear test results showed that the bond strength of specimens anodised at 20℃for 15 min improved by 135.9%and 95.4%,respectively,in comparison with that of acid pickled and grinded specimens(without RPC treatment).Although increasing the anodising temperature and duration produced rougher titanium surfaces,the adhesively bonded joints were not strong enough due to relatively friable titanium oxide layers.

关键词： Carbon Fibre Reinforced Polymer(CFRP) Titanium alloy Anodising Resin pre-coating Adhesive joints

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纳米微粒在改善润滑方面的研究进展

材料导报 2011年第1期25卷 45-48,69页

作者：梁秀娟胡小芳嵇海旭胡大为华南理工大学机械与汽车工程学院广州510640 广东海洋大学工程学院机械系湛江524088

由于纳米微粒的独特性能,使其在改善润滑方面取得了很大进步。通过对纳米微粒特性的描述和纳米微粒在润滑性能方面的测试以及国内外已经取得的各种纳米微粒在润滑方面的一些成果,阐述了当今纳米微粒在改善润滑方面的发展状况和纳米微粒... 详细信息

由于纳米微粒的独特性能,使其在改善润滑方面取得了很大进步。通过对纳米微粒特性的描述和纳米微粒在润滑性能方面的测试以及国内外已经取得的各种纳米微粒在润滑方面的一些成果,阐述了当今纳米微粒在改善润滑方面的发展状况和纳米微粒的润滑机理,同时指出了目前发展的不足。

关键词：纳米微粒摩擦学性能减摩抗磨

Effect of Central Multiphase Microstructure of Thick Plates on Work Hardening and Crack Propagation

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 325-338页

作者： Lei hu Liqin Zhang Feng hu Kuan Zheng Guohong Zhang Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081China Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081China Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081China

The effect of multiphase microstructure in the center segregation zones(CSZ)of high-strength steel thick plates on work hardening characteristics and crack initiation/propagation were *** was correlated with deformation damage behavior by using Taylor factor(TF)gradients,kernel average misorientation(KAM),and geometric necessary dislocation(GND)*** results show that the segregation leads to a mixed structure of ferrite(soft phase)and martensite/bainite(hard phase)in the center of the thick *** to the 1/4 thickness(1/4 T)region,grain refinement occurred in the CSZ,with KAM values increasing from 0.24 to 0.49 and a decrease in the proportion of high-angle grain boundaries(>15°)from 77.4 to 51.8%.In the process of deformation,due to the influence of grain refinement and adjacent martensite/bainite,ferrite grains were divided into structural units with different TF *** higher KAM value and GND density at the interface between soft/hard phases resulted in severe work *** addition,the presence of micron-sized inclusions in the CSZ caused local strain concentration and non-continuous deformation of the matrix,which induced crack *** fracture surface showed a mixed mode of brittle cleavage fracture and ductile fracture.

关键词： Thick plate Center segregation zone Multiphase microstructure Taylor factor Crack propagation

Paracrine function amplifies pro-tumor electrochemical signal within neuron-glioma synapses

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Science China(Life Sciences) 2024年第6期67卷 1318-1320页

作者： Yan hu Peishan hu Xiaozhong Peng Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE State Key Laboratory of BiotherapyWest China Second University HospitalSichuan UniversityChengdu 610041China Guangdong Institute of Gastroenterology Department of General SurgeryGuangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesThe Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510655China Department of Molecular Biology and Biochemistry Institute of Basic Medical SciencesMedical Primate Research CenterNeuroscience CenterChinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100730China State Key Laboratory of Respiratory Health and Multimorbidity Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100730China Institute of Laboratory Animal Science Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Neuronal activity plays a pivotal role in various physiological processes,including tissue development,homeostasis,and *** in recent years have improved our understanding of neuronal activity in brain cancers,such as glioblastoma(GBM)and diffuse midline gliomas(DMG),which are among the most prevalent and lethal cancers affecting children and ***,the neurons regulate brain cancers via two routes.

关键词： glioma homeostasis function

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北极航道航行船舶操纵性设计需求分析

中国舰船研究 2015年第3期10卷 37-44页

作者：胡晓芳蔡敬标中国舰船研究设计中心中国人民解放军92537部队

随着全球变暖引起的海冰大面积消退,使得北极海上通航逐渐成为可能,而北极航道地形复杂、气候寒冷的特点对航行于该海域船舶的操纵性提出了不同的要求。分析北极航道水域特点和气候环境条件,提出浅水、狭航道、浮冰、气温、能见度和风... 详细信息

随着全球变暖引起的海冰大面积消退,使得北极海上通航逐渐成为可能,而北极航道地形复杂、气候寒冷的特点对航行于该海域船舶的操纵性提出了不同的要求。分析北极航道水域特点和气候环境条件,提出浅水、狭航道、浮冰、气温、能见度和风等因素为开展该航区航行船舶操纵性设计所必须考虑的因素,而由这些因素引起的船舶航行速度的下降也是影响操纵性的因素之一。通过对上述因素的分析,建议在设计船舶时选取更大的舵面积系数,并留取一定的设计舵角余量,同时在设计阶段还应开展多个航速的操纵性计算预报。

关键词：操纵性北极航道极区航行