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Chinese Journal of Mechanical Engineering 2023年第3期36卷 110-122页

作者： Peiyi Wang Xinhua Yang Xiangyang Wang sheng guo School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Guangdong Provincial Key Lab of Robotics and Intelligent System Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518005China

Continuum robots actuated by flexible rods have large potential applications,such as detection and operation tasks in confined environments,since the push and pull actuation of flexible rods withstand tension and compressive force,and increase the structure's *** this paper,a generalized kinetostatics model for multi-module and multi-segment continuum robots considering the effect of friction based on the Cosserat rod theory is ***,the model is applied to a two-module rod-driven continuum robot with winding ropes to analyze its deformation and load *** different in-plane configurations under the external load term as S1,S2,C1,and C2 are *** a bending plane as an example,the tip deformation along thex-axis of these shapes is simulated and compared,which shows that the load capacity of C1 and C2 is generally larger than that of S1 and ***,the deformation experiments and simulations show that the maximum error ratio without external loads relative to the total length is no more than 3%,and it is no more than 4.7%under the external *** established kinetostatics model is proven sufficient to accurately analyze the rod-driven continuum robot with the consideration of internal friction.

关键词： Rod-driven continuum robot Kinetostatic model Cosserat rod theory Deformation and stiffness analysis

Dynamic Analysis and Performance Verification of a Novel Hip Prosthetic Mechanism

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 131-147页

作者： Majun Song sheng guo Xiangyang Wang Haibo Qu School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

To assist an amputee in regaining his or her daily quality of life,based on analysis of the motion characteristics of the human hip,a 2-UPR/URR parallel mechanism with a passive limb was *** inverse kinematics of this mechanism was analyzed based on a closed-loop vector *** constrained Jacobian matrix and kinematic Jacobian matrix of each limb were then analyzed,and a 6×6 fully Jacobian matrix was *** on this,kinematic performances were analyzed and ***,the dynamic model of the mechanism was constructed based on the virtual work principle,and its theoretical solution was compared with the numerical results,which were obtained in a simulation *** showed that the prosthetic mechanism had a larger rotating workspace and better mechanical performance,which accorded a range of motion and bearing capacity similar to that of the human hip in multiple gait ***,the validity of the dynamic model and inverse kinematics were verified by comparing the theoretical and simulation ***,with flexion and extension,the torque change in the hip prosthetic mechanism was similar to that of the human hip,which demonstrated the feasibility of the hip prosthetic mechanism and its good dynamic performance.

关键词： Screw theory Prosthetic hips Workspace Buckling analysis Virtual work principle Dynamics

Reconfigurable parallel mechanisms with planar five-bar metamorphic linkages

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Science China(Technological Sciences) 2014年第1期57卷 210-218页

作者： YE Wei FANG YueFa guo sheng Department of Mechanical Engineering Beijing Jiaotong University

This paper presents the idea of constructing reconfigurable limbs by integrating metamorphic linkages as *** planar five-bar metamorphic linkages that have three phases resulting from locking of motors are *** the assumption that the constraint exerted by the reconfigurable limb can switch between no constraint,a constraint force,and a constraint couple,the output motions of the metamorphic linkage in its two planar four-bar linkage phases are *** adding an appropriate joint to planar four-bar linkages with translational output,four planar five-bar linkages that can be employed in the construction of reconfigurable limbs are *** chains that can provide a constraint couple and a constraint force are synthesized based on screw *** limbs that have three configurations associated with the three distinct phases of the metamorphic linkages are assembled with planar five-bar metamorphic linkages and serial chains with four degrees of freedom.A class of reconfigurable parallel mechanisms are constructed by connecting a moving platform and a base with three identical reconfigurable *** degrees of freedom of the reconfigurable parallel mechanism in different configurations with the metamorphic linkages in different phases are ***,the actuation scheme for this kind of mechanisms is addressed.

关键词： reconfigurable limb planar five-bar metamorphic linkage screw theory reconfigurable parallel mechanism actuation scheme

Upper Cretaceous alluvial fan deposits in the Jianglangshan Geopark of Southeast China:implications for bedrock control on Danxia landform evolution

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Journal of Mountain Science 2017年第5期14卷 926-935页

作者： CHEN Liu-qin guo Fu-sheng State Key Laboratory Breeding Base of Nuclear Resources and Environment East China University of TechnologyNanchang 330013 China School of Earth Sciences East China University of Technology Nanehang 330013 China

The Jianglangshan Geopark in the western Zhejiang Province of Southeast China is well-known for its spectacular red-colored sandstone landforms. Little is known about the depositional processes of the conglomerate-dominated Fangyan Formation, the lithologic base of the Danxia landforms in this geopark. Based on detailed field investigation of lithology, sedimentary structures, bed thickness and geometry, five facies are recognized: facies A(matrixsupported cobble conglomerate), facies B(pebble conglomerate), facies C(pebbly sandstone), facies D(fine-grained sandstone) and facies E(mudstone). The results show that streamflow-dominated fans were the main depositional processes responsible for the accumulation of the Fangyan Formation along the mountain fronts. These fan conglomerates form the base for the evolution of the Danxia landscapes owing to the uplift and erosion of the study area. In contrast, the fine-grained sedimentary successions produced by fluvial floodplains in the distal part of the fans were thinner and more easily weathered. Such sedimentary facies distribution patterns were thought to be similar during Late Cretaceous across Southeast China. The Danxia landforms are largely the geographical expressions of the conglomerate-dominated redbeds in the proximal-middle fans.

关键词： Danxia landform Late Cretaceousredbeds Alluvial fan Jianglangshan Geopark Landscape evolution

Preparation of Al-Cu-Fe-(Sn,Si) quasicrystalline bulks by laser multilayer cladding

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 434-440页

作者： Li-ping Feng Eric Fleury guo-sheng Zhang Tianjin Research Institute of Construction Machinery Tianjin 300409 China State Key Laboratory of Tribology Tsinghua University Beijing 100084 China Center for High Temperature Energy Materials Korea Institute of Science ＆ Technology （K/ST） Seou1130 650 Korea

（A165Cu20Fe15）100-xSnx （x=0, 12, 20, 30） and A157SitoCulsFe15 powders were cladded on a medium carbon steel （45# steel） substrate by laser multilayer cladding, respectively. The phases and properties of the produced quasicrystalline bulks were investigated. It was found that the main phases in the A165Cu2oFe15 sample were crystalline L-Al13Fe4 and icosahedral quasicrystal together with a small volume fraction of 0-A12Cu phase. The volume fraction of icosahedral phase decreased as the Sn content in the （A165Cu20Fe18）100-xSnx samples increased owing to the formation of β-CuSn phase. The increase of Sn content improved the brittleness of the quasicrystal samples. The morphology of the solidification microstructure in the Al57Si10Cu18Fe15 sample changed from elongated shape to spherical shape due to the addition of Si. The nanohardness of the laser multilayer cladded quasicrystal samples was equal to that of the as-cast sample prepared by vacuum quenching. In terms of hardness, the laser cladded A157Si10Cu18Fe15 quasicrystalline alloy has the highest value among all the investigated samples.

关键词： quasicrystals laser cladding phase composition morphology mechanical properties nanohardness

General Model of Temperature-dependent Modulus and Yield Strength of Thermoplastic Polymers

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Chinese Journal of Polymer Science 2020年第4期38卷 382-393,I0007页

作者： Ping-Yuan Huang Zhan-sheng guo Jie-Min Feng Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072China

A general model was developed to predict the temperature-dependent modulus and yield strength of different thermoplastic *** model,which depends on only two parameters with clear and specific physical meanings,can describe the temperaturedependent modulus and yield strength of thermoplastic polymers over the full glass transition *** temperature-dependent modulus and yield strength of three thermoplastic polymers were measured by uniaxial tension tests over a temperature range of 243-383 *** predictions showed excellent agreement with the experimental *** analysis of model input parameters showed negligible effect on the present general *** universality of the present general model was further validated,showing excellent agreement with published experimental data on other thermoplastic polymers and their composites.

关键词： Thermoplastics Modulus Yield strength Modeling Glass transition

Developing natural marine products for treating liver diseases

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World Journal of Clinical Cases 2022年第8期10卷 2369-2381页

作者： Qian Wei Jin-sheng guo Department of Gastroenterology and Hepatology Zhongshan HospitalFudan UniversityShanghai 200032China

In recent years,marine-derived bioactive compounds have gained increasing attention because of their higher biodiversity vs land-derived compounds.A number of marine-derived compounds are proven to improve lipid metabolism,modulate the gut microbiota,and possess anti-inflammatory,antioxidant,antibacterial,antiviral,and antitumor *** the increasing understanding of the molecular landscape underlying the pathogenesis of chronic liver diseases,interest has spiked in developing new therapeutic drugs and medicine food homology from marine sources for the prevention and treatment of liver diseases.

关键词： Natural marine products Liver disease Treatment Liver

Robust sliding mode control of general time-varying delay stochastic systems with structural uncertainties

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Control Theory and Technology 2014年第4期12卷 357-367页

作者： sheng-guo WANG Libin BAI Mingzhi CHEN Department of Engineering Technology and Department of Software and Information Systems (Graduate Faculty) University of North Carolina at Charlotte (UNC Charlotte) Department of Software and Information Systems UNC Charlotte NC 28223-0001 U.S.A. College of Mathematics and Computer Science Fuzhou University

This paper presents a new robust sliding mode control （SMC） method with well-developed theoretical proof for general uncertain time-varying delay stochastic systems with structural uncertainties and the Brownian noise （Wiener process）. The key features of the proposed method are to apply singular value decomposition （SVD） to all structural uncertainties and to introduce adjustable parameters for control design along with the SMC method. It leads to a less-conservative condition for robust stability and a new robust controller for the general uncertain stochastic systems via linear matrix inequality （LMI） forms. The system states are able to reach the SMC switching surface as guaranteed in probability 1. Furthermore, it is theoretically proved that the proposed method with the SVD and adjustable parameters is less conservatism than the method without the SVD. The paper is mainly to provide all strict theoretical proofs for the method and results.

关键词： Robust control Time-varying delay systems Stochastic systems Lyapunov methods Sliding mode control Time-varying systems

Evaluation of Chaotic Demodulator for EBPSK Signals

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Journal of Electronic Science and Technology 2016年第3期14卷 262-267页

作者： Song Zhang guo-sheng Rui Yang Zhang the Department of Electronics and Information Engineering NavalAeronautical and Astronautical UniversityYantai 264001China

Based on the theory of Duffing oscillator weak signal detection and the technology of extended binary phase shift keying （EBPSK） modulation, the chaotic demodulator using the Duffing oscillator for EBPSK signals was proposed. The proposed demodulator could avoid the problem of demodulation filters design, and shows the excellent anti-noise capability of chaotic oscillator detection. Numerical and experimental tests were taken to investigate the impact of modulation parameters T and 0 on bit error performance of the proposed method, and the performance limits were gotten. The results show that the proposed chaotic demodulator works well under a very low signal-to-noise ratio （SNR） conditions, and gets SNR gains about 20 dB to 30 dB from the impulse filter.

关键词： Index Terms Duffing oscillator demodulation extended binary phase shift keying (EBPSK) receiver filter.

Annealing-induced Grain Refinement in a Nanostructured Ferritic Steel

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Journal of Materials Science & Technology 2012年第1期28卷 41-45页

作者： Limin Wang Zhenbo Wang sheng guo Ke Lu sheng guo and Ke Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

A nanostructured surface layer with a mean ferrite grain size of -8 nm was produced on a Fe-gCr steel by means of surface mechanical attrition treatment. Upon annealing, ferrite grains coarsen with increasing temperature and their sizes increase to -40 nm at 973 K. Further increasing annealing temperature leads to an obvious reduction of ferrite grain sizes, to -14 nm at 1173 K. The annealing-induced grain refinement is analyzed in terms of phase transformations in the nanostructured steel.

关键词： Nanostructured Surface mechanical attrition treatment (SMAT) Ferritic steel Grain refinement Austenitization