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CAAI Transactions on Intelligence Technology 2023年第3期8卷 622-634页

作者： zhan li Shuai li Department of Computer Science Swansea UniversitySwanseaUK College of Engineering Swansea UniversitySwanseaUK

Manipulators actuate joints to let end effectors to perform precise path tracking *** neural network which is described by dynamic models with parallel processing capability,is a powerful tool for kinematic control of *** to physical limitations and actuation saturation of manipulator joints,the involvement of joint constraints for kinematic control of manipulators is essential and ***,current existing manipulator control methods based on recurrent neural networks mainly handle with limited levels of joint angular constraints,and to the best of our knowledge,methods for kinematic control of manipulators with higher order joint constraints based on recurrent neural networks are not yet *** this study,for the first time,a novel recursive recurrent network model is proposed to solve the kinematic control issue for manipulators with different levels of physical constraints,and the proposed recursive recurrent neural network can be formulated as a new manifold system to ensure control solution within all of the joint constraints in different *** theoretical analysis shows the stability and the purposed recursive recurrent neural network and its convergence to *** results further demonstrate the effectiveness of the proposed method in end‐effector path tracking control under different levels of joint constraints based on the Kuka manipulator *** with other methods such as the pseudoinverse‐based method and conventional recurrent neural network method substantiate the superiority of the proposed method.

关键词： dynamic neural networks recursive computation robotic manipulator

Thermodynamic Performance Comparison and Optimization of sCO_(2)Brayton Cycle,tCO_(2)Brayton Cycle and tCO_(2)Rankine Cycle

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Journal of Thermal Science 2023年第2期32卷 611-627页

作者： JIANG Yu zhan li TIAN Xuelian NIE Changhua Nuclear Power Institute of China Chengdu 610213China

In this paper,to further improve thermodynamic performance of supercritical carbon dioxide cycle,simple/recompression transcritical carbon dioxide Brayton cycle(STBC/RTBC)and simple/recompression transcritical carbon dioxide Rankine cycle(STRC/RTRC)are *** and exergy performance analysis and optimization for the above four transcritical CO_(2)cycles and simple/recompression supercritical cycle(SSBC/RSBC)are *** effect of key thermodynamic parameters on those CO_(2)cycle performance is *** indicate that the improvements of thermodynamic performance of CO_(2)cycle are obvious when transcritical Brayton and Rankine cycle are applied in *** the same range of optimization variables,the maximum thermal efficiency improvements of RTRC and RTBC are 4.98%and 3.6%,and maximum exergy efficiency improvements of RTRC and RTBC are 7.08%and 5.13%when compared with ***,the thermodynamic performances of STBC and STRC are also outstanding than that of *** work provides a way to further improve the thermodynamic performance of CO_(2)power cycle.

关键词： thermodynamic performance supercritical carbon dioxide transcritical carbon dioxide Brayton cycle Rankine cycle

Re:''Laparoscopic vs open approach to resection of hepatocellular carcinoma in patients with known cirrhosis:Systematic review and meta-analysis''

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World Journal of Gastroenterology 2015年第1期21卷 377-378页

作者： zhan-zhan li li-zhang Chen Department of Epidemiology and Health Statistics School of Public HealthCentral South University

Twaij and colleagues have carried out a meta-analysis of cohort studies to review the currently available literature comparing laparoscopic to open resection of hepatocellular carcinoma in patients with known liver **... 详细信息

关键词： Meta-analysis Standardized mean difference Heterog

Spin Accumulation of Spinor Atoms in Optical Lattices

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Communications in Theoretical Physics 2007年第5期47卷 777-780页

作者： li Hong JIANG zhan-Feng Beijing National Laboratory for Condensed Matter Physics Institute of Physics the Chinese Academy of SciencesBeijing 100080. China

We obtain an effective spin correlation Hamiltonian describing the interaction of light with a two-level atom, then we investigate the classical trajectory of the two-level atom system by numerical integration of the Heisenberg equation of motion. Our results show that the spin accumulation is a very popular phenomenon as long as the spin character cannot be ignored in the Hamiltonian. We propose experimental protocol to observe this new phenomenon in further experiments.

关键词： a two-level atom optical lattices Spin

Ultrasmall Nanoparticle ROS Scavengers Based on Polyhedral Oligomeric Silsesquioxanes

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Chinese Journal of Polymer Science 2020年第11期38卷 1149-1156,I0004页

作者： zhan li Haotian li Jianhua zhang Xianhu liu Zhipeng Gu Yiwen li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China School of Materials Science and Engineering Xihua UniversityChengdu 610039China National Engineering Research Center for Advanced Polymer Processing Technology Zhengzhou UniversityZhengzhou 450002China

Although tremendous efforts have been devoted to the structural and functional tailoring of natural polyphenol-functionalized nan oparticles,preparing ultrasmall sized(ligomeric silsesquioxanes(POSS)-based polyphenol nanopartides(T8^-,T10^-,and T12^-GAPOSS)by accurately functionalizing the POSS surface with plant polyphenol gallic acid units via thiol-Michael"click"*** polyphenol nanoparticles exhibited strong free radical scavenging capacity,good biocompatibility and ability to resist cell oxidative damage,which dem on strated great potentials in inhibiting oxidative stress in duced pathologies.

关键词： Polyhedral oligomeric silsesquioxanes(POSS) Polyphenol Ultrasmall nanoparticles Free radical scavenging

Uniform persistence of multispecies ecological competition predator-pray system with Holling Ⅲ type functional response

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 410-412页

作者： li zhan li ling-xiao WANG Ke Dept. of Math. Zhengzhou Univ. Zhengzhou 450001 China Science College Henan Univ. of Sci. and Tech. Luoyang 471003 China Dept. of Math. Harbin Inst. of Tech. Weihai 264209~ China

The main purpose of this paper is to study the persistence of the general multispecies competition predator-pray system with Holling Ⅲ type functional response. In this system, the competition among predator species and among prey species are simultaneously considered. By using the comparison theory and qualitative analysis, the sufficient conditions for uniform strong persistence are obtained.

关键词： competition predator-pray system Holling Ⅲ type functional response persistence

Effect of electric pulse on the crystal structure of solidified copper ingots

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 556-562页

作者： li-hua Zhao li zhan Hao Bai Da-qiang Cang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing Shougang Steel Co. Ltd.Sales Company

To obtain advanced quality pure copper, the microstructure of solidified copper was optimized by imposing electric pulse on liquid copper in this study. Experiments were performed to determine the effect of electric pulse voltage, arrangement mode of electrodes, and energy input on the microstructure of solidified copper. The results show that, when the energy input of electric pulse is bigger than 28.95 kJ per ton copper, the percent of fine grains increases noticeably with the increase of energy input; but when the energy input of electric pulse is smaller than 28.95 kJ per ton copper, the percent of fine grains decreases with the increase of energy input. The influence order of above factors on grain refinement is electric pulse voltage 〉 arrangement mode of electrodes 〉 energy input. According to the above experimental results, the optimum process conditions are chosen as the voltage being 400 V and the energy input greater than 28.95 kJ per ton copper. Meanwhile, the best arrangement mode of electrodes should be that, one electrode is immerged in the middle of liquid copper in the crystallizer, and the other is connected to the inner wall of the crystallizer, which is divided into two electrode poles for the symmetrical electric field distribution.

关键词： copper solidification crystal structure electric pulse

Modeling the blast load induced by a close-in explosion considering cylindrical charge parameters

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Defence Technology（防务技术） 2023年第6期24卷 83-108页

作者： Yi Fan li Chen zhan li Heng-bo Xiang Qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjingJiangsu210007China Engineering Research Center of Safety and Protection of Explosion&Impact of the Ministry of Education Southeast UniversityNanjingJiangsu211189China

Structural damage is significantly influenced by the various parameters of a close-in *** establish a close-in blast loading model for cylindrical charges according to these parameters,a series of field experiments and a systematic numerical analysis were conducted.A high-fidelity finite element model developed using AUTODYN was first validated using blast data collected from field tests conducted in this and previous studies.A quantitative analysis was then performed to determine the influence of the charge shape,aspect ratio(length to diameter),orientation,and detonation configuration on the characteristics and distributions of the blast loading(incident peak overpressure and impulse)according to scaled *** results revealed that the secondary peak overpressure generated by a cylindrical charge was mainly distributed along the axial direction and was smaller than the overpressure generated by an equivalent spherical *** effects of charge shape on the blast loading at 45°and 67.5°in the axial plane could be neglected at scaled distances greater than 2 m/kg^(1/3);the effect of aspect ratios greater than 2 on the peak overpressure in the 90°(radial)direction could be neglected at all scaled distances;and double-end detonation increased the radial blast loading by up to 60%compared to singleend ***,an empirical cylindrical charge blast loading model was developed considering the influences of charge aspect ratio,orientation,and detonation *** results obtained in this study can serve as a reference for the design of blast tests using cylindrical charges and aid engineers in the design of blast-resistant structures.

关键词： Cylindrical charge Secondary peak overpressure Aspect ratio Orientation Detonation initiation point Blast loading model

The Effect of Method of Constructing the Mass Distribution on Single Stellar Populations

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Chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 371-378页

作者： Feng-Hui zhang li-Fang li zhan-Wen Han National Astronomical Observatories Yunnan Observatory Chinese Academy of SciencesKunming 650011

We use two methods of constructing the initial mass distribution, the traditional way and Monte Carlo simulation, to obtain integrated U - B, B - V,V-R and V-I colours and absorption-line indices defined by the lick Observatory image dissector scanner （referred to as lick/IDS）, for instantaneous burst solarmetallicity single stellar populations with ages in the range 1-15Gyr. We find that the evolutionary curves of all colours obtained by the traditional method are smoother than those by Monte Carlo simulation, that the U- B and B- V colours obtained by the two methods agree with one another, while the V - R and V - I colours by the traditional method are bluer than those by Monte Carlo simulation.A comparison of the lick/IDS absorption-line indices shows that the variations in all the indices by the traditional method are smoother than that for the Monte Carlo simulation, and that all the indices except for TiO1 and TiO2 are consistent with those for the Monte Carlo simulation.

关键词： star: evolution - galaxies: star clusters- galaxies: stellar content

Experimental investigation of engineered geopolymer composite for structural strengthening against blast loads

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Defence Technology（防务技术） 2024年第2期32卷 496-509页

作者： Shan liu Chunyuan liu Yifei Hao Yi zhang li Chen zhan li Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Prefabricated Buildings and Intelligent Construction Hebei University of TechnologyTianjin 300400China Institute of Defense Engineering AMSPLABeijing 100850China Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189JiangsuChina State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjing 210007JiangsuChina

The recent increase in blast/bombing incidents all over the world has pushed the development of effective strengthening approaches to enhance the blast resistance of existing civil *** geopolymer composite(EGC)is a promising material featured by eco-friendly,fast-setting and strain-hardening characteristics for emergent strengthening and ***,the fiber optimization for preparing EGC and its protective effect on structural elements under blast scenarios are *** this study,laboratory tests were firstly conducted to evaluate the effects of fiber types on the properties of EGC in terms of workability,dry shrinkage,and mechanical properties in compression,tension and *** experimental results showed that EGC containing PE fiber exhibited suitable workability,acceptable dry shrinkage and superior mechanical properties compared with other types of *** that,a series of field tests were carried out to evaluate the effectiveness of EGC retrofitting layer on the enhancement of blast performance of typical *** tests include autoclaved aerated concrete(AAC)masonry walls subjected to vented gas explosion,reinforced AAC panels subjected to TNT explosion and plain concrete slabs subjected to contact *** was found that EGC could effectively enhance the blast resistance of structural elements in different *** AAC masonry walls and panels,with the existence of EGC,the integrity of specimens could be maintained,and their deflections and damage were significantly *** plain concrete slabs,the EGC overlay could reduce the diameter and depth of the crater and spallation of specimens.

关键词： Engineered geopolymer composites Fiber optimization Strengthening material Blast resistance Masonry wall Reinforced AAC panel Plain concrete slab