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Precision measurement and compensation of kinematic errors for industrial robots using artifact and machine learning

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Advances in Manufacturing 2022年第3期10卷 397-410页

作者： Ling-bao Kong Yi yu Shanghai Engineering Research Center of Ultra-precision Optical Manufacturing Department of Optical Science and EngineeringFudan UniversityShanghai 200438People's Republic of China

Industrial robots are widely used in various areas owing to their greater degrees of freedom(DOFs)and larger operation space compared with traditional frame movement systems involving sliding and rotational ***,the geometrical transfer of joint kinematic errors and the relatively weak rigidity of industrial robots compared with frame movement systems decrease their absolute kinematic accuracy,thereby limiting their further application in ultraprecision *** imposes a stringent requirement for improving the absolute kinematic accuracy of industrial robots in terms of the position and orientation of the robot arm *** measurement and compensation methods for industrial robots either require expensive measuring systems,producing positioning or orientation errors,or offer low measurement ***,a kinematic calibration method for an industrial robot using an artifact with a hybrid spherical and ellipsoid surface is proposed.A system with submicrometric precision for measuring the position and orientation of the robot arm end is developed using laser displacement ***,a novel kinematic error compensating method involving both a residual learning algorithm and a neural network is proposed to compensate for nonlinear errors.A six-layer recurrent neural network(RNN)is designed to compensate for the kinematic nonlinear errors of a six-DOF industrial *** results validate the feasibility of the proposed method for measuring the kinematic errors of industrial robots,and the compensation method based on the RNN improves the accuracy via parameter *** studies show that the measuring system and compensation method can reduce motion errors by more than 30%.The present study provides a feasible and economic approach for measuring and improving the motion accuracy of an industrial robot at the submicrometric measurement level.

关键词： Industrial robot Kinematic error Calibration Machine learning Recurrent neural network(RNN)

Flow stress model considering the transformation-induced plasticity effect and the inelastic strain recovery behavior

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 185-191页

作者： Hai-yan yu Li bao School of Automotive Engineering Tongji University Shanghai 200092 China

On the basis of continuum mechanics and the Mori-Tanaka mean field theory, a micro-mechanical flow stress model that considered both the transformation-induced plasticity （TRIP） effect and the inelastic strain recovery behavior of TRIP multiphase steels was presented. The relation between the volume fraction of constituent phases and plastic strain was introduced to characterize the transformation-induced plasticity effect of TRIP steels. Loading-unloading-reloading uniaxial tension tests of TRIP600 steel were carried out and the strain recovery behavior after unloading was analyzed. From the experimental data, an empirical elastic modulus expression is extracted to characterize the inelastic strain recovery. A comparison of the predicted flow stress with the experimental data shows a good agreement. The mechanism of the transformation-induced plasticity effect and the inelastic recovery effect acting on the flow stress is also discussed in detail.

关键词： flow stress transformation-induced plasticity inelastic strain elastic modulus

Enhanced cooperative packet retransmission employing joint cooperative diversity and symbol mapping diversity

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1090-1098页

作者： Wei JI bao-yu ZHENG Electronic Engineering Department Shanghai Jiao Tong University Shanghai 200240 China Institute qf Signal Processing and Transmission Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

A joint cooperation diversity and symbol mapping diversity (SMD) strategy is proposed for cooperative packet retransmission system with high-order modulation such as 16QAM. Substantial SER/BER (symbol error rate/bit error rate) gains result from multiple packet transmissions over independent paths and distinct bit-to-symbol mappings for each packet transmis-sion. The SER/BER performance of relay assisted retransmission system is analyzed. Simulation results show that the joint-diversity strategy can provide more BER gains than other relaying strategies (i.e., decode-and-forward and constellation rearrangement relaying strategies) when no relay makes a decision error; but if some relays make decision errors, the joint-di-versity strategy outperforms other relaying strategies only when the relays are closer to the source than to the destination.

关键词： Cooperative retransmission Hybrid automatic repeat request (HARQ) Cooperative diversity Symbol mapping diversity (SMD)

血必净注射液结合常规疗法对大面积烧伤患者脏器功能损害的保护作用

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上海中医药杂志 2011年第3期45卷 37-38页

作者：蒋金珩喻三宝沈小刚虞宏纲宗文政浙江省义乌市中心医院烧伤整形科浙江义乌322000

目的观察血必净注射液对大面积烧伤患者脏器功能损害的保护作用。方法将67例大面积烧伤患者随机分为对照组(34例)和观察组(33例)。两组均给予西医常规治疗,观察组在西医常规治疗的基础上加用血必净注射液静脉滴注,疗程7天。观察两组患... 详细信息

目的观察血必净注射液对大面积烧伤患者脏器功能损害的保护作用。方法将67例大面积烧伤患者随机分为对照组(34例)和观察组(33例)。两组均给予西医常规治疗,观察组在西医常规治疗的基础上加用血必净注射液静脉滴注,疗程7天。观察两组患者治疗前后肝肾功能、凝血功能,C-反应蛋白含量等变化。结果治疗后观察组肝肾功能、凝血功能明显改善(P<0.05),C-反应蛋白含量降低(P<0.05);观察组肝功能、凝血功能、C-反应蛋白的改善优于对照组(P<0.05)。结论血必净注射液可通过改善凝血功能、降低炎性介质的释放来保护大面积烧伤患者重要脏器的功能。

关键词：大面积烧伤多器官功能障碍综合征血必净注射液

Molecular structure characterization of middle-high rank coal via^(13)C NMR,XPS,and FTIR spectroscopy

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China Geology 2024年第4期7卷 702-713页

作者： xiao-ming Ni Jing-shuo Zhang xiao-kai Xu bao-yu Wang School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China Institute of Resources&Environment Henan Polytechnic UniversityJiaozuo 454000China

Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in ***(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and *** results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring *** heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and *** stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy *** Stretching Energy The size of EB determines how tight the structure *** research results provide a method and reference for the study of the molecular structure of medium and high coal ranks.

关键词： Molecular structure model Carbon-13 nuclear magnetic resonance(NMR) X-ray photoelectron spectroscopy(XPS) Fourier transform infrared spectroscopy(FTIR) Coal

Ultrahigh cycle fatigue fracture mechanism of high-quality bearing steel obtained through different deoxidation methods

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International Journal of Minerals,Metallurgy and Materials 2021年第5期28卷 804-815页

作者： Wei xiao Yan-ping bao Chao Gu Min Wang yu Liu Yong-sheng Huang Guang-tao Sun State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China ZENITH Steel Group Co.Ltd. Changzhou 213000China

The mechanism of oxide inclusions in fatigue crack initiation in the very-high cycle fatigue(VHCF)regime was clarified by subjecting bearing steels deoxidized by Al(Al-deoxidized steel)and Si(Si-deoxidized steel)to ultrasonic tension-compression fatigue tests(stress ratio,R=−1)and analyzing the characteristics of the detected *** show that the main types of inclusions in Si-and Al-deoxidized steels are silicate and calcium aluminate,*** content of calcium aluminate inclusions larger than 15μm in Si-deoxidized steel is lower than that in Al-deoxidized steel,and the difference observed may be attributed to different inclusion generation processes during *** differences in their cleanliness and total oxygen contents,the Si-and Al-deoxidized steels show similar VHCF *** factors causing fatigue failure in these steels reveal distinct *** aluminate inclusions are responsible for the cracks in Al-deoxidized *** comparison,most fatigue cracks in Si-deoxidized steel are triggered by the inhomogeneity of a steel matrix,which indicates that the damage mechanisms of the steel matrix can be a critical issue for this type of steel.A minor portion of the cracks in Si-deoxidized steel could be attributed to different types of *** mechanisms of fatigue fracture caused by calcium aluminate and silicate inclusions were further *** aluminate inclusions first separate from the steel matrix and then trigger crack *** inclusions and the steel matrix are closely combined in a fatigue process;thus,these inclusions have mild effects on the fatigue life of bearing ***/Mn deoxidation is an effective method to produce high-quality bearing steel with a long fatigue life and good liquid steel fluidity.

关键词： bearing steel non-aluminum deoxidation inclusion fatigue crack initiation tessellated stresses

Influence of Backbone and Axial Substituent of Catalyst onα-Imino-ketone Nickel Mediated Ethylene(Co)Polymerization

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Chinese Journal of Polymer Science 2022年第5期40卷 469-477页

作者： yu-Kai Chu xiao-Qiang Hu yue Zhang Da-Jun Liu Yi-Xin Zhang Zhong-bao Jian College of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 730022China

Theα-imino-ketone nickel catalyst is an emerging versatile platform that is easy to prepare and allows for the production of branched high molecular weight functionalized ***,study on this catalyst system is rare thus *** this contribution,by introducing different backbones,flexible and rigid axial substituents into theα-imino-ketone framework,a family of cationic nickel catalysts were synthesized and fully *** the addition of any activator,systematic studies on ethylene polymerization and copolymerization with polar monomers were performed to explore the influence of both backbone and axial substituent on catalytic activity,polymer molecular weight,branching density and *** particular,owing to the unique semi-opening feature of theα-imino-ketone framework,the preferred nickel catalyst exhibited high activity of 175 kg·mol^(-1)·h^(-1)to produce functionalized polyethylene with molecular weight of 13.4 kg·mol^(-1)and comonomer incorporation of 2.9 mol%.

关键词： Olefin polymerization α-Imino-ketone ligand Nickel catalyst Polar monomer

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-yu Li Li-Le Liu Guo-Xiang Dong xiao-bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were *** volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov *** in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and *** fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap *** results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing *** on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

A Resonantly Pumped Q-Switched Er:Lu_(2)SiO_(5) Laser

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Chinese Physics Letters 2013年第3期30卷 81-83页

作者： YAO bao-Quan yu xiao LIU xiao-Lei DUAN xiao-Ming JU You-Lun WANG yue-Zhu National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbin 150001

We describe the cw and Q-switched actions of a novel erbium-doped crystal Er:Lu_(2)SiO_(5) pumped by a MgO:PPLN-OPO at 1536 *** efficient 1580.9 nm cw laser with the output power of 608 mW is obtained when the incident power is 4.5 W,corresponding to a slope efficiency of 11.1%.In the Q-switched operation,the pulse energy up to 1.2 mJ is obtained at a repetition rate of 200 Hz.

关键词： switched pumped OPO