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Nano Research 2024年第5期17卷 4517-4524页

作者： Jiwei Li Yao Xie Renrui sun Junxun Zhou lining sun Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Department of Physics College of SciencesShanghai UniversityShanghai 200444China School of Medicine Shanghai UniversityShanghai 200444China

Luminescence quench is common in overdoped upconversion *** methods have been proposed to counteract the adverse effects of concentration quenching on luminescence,but in upconversion nanoparticles that are highly doped with both sensitizers and activators,the factors that contribute to the diminishing of the emission cannot be summarized by a single ***,a core-shell design is used to spatially separate the sensitizer(Yb^(3+))and activator(Er^(3+))and to modulate the emission by changes in the distribution position as well as the concentration of the dopant ions in order to probe the factors affecting the *** the sensitizer ions are located in the core,the luminescence intensity of the nanoparticles is significantly weaker than that of the other distribution,which implies that the effect of sensitizer and activator on luminescence in the highly doped state has a different and more complex *** intensity of the emission is more affected by Yb^(3+)than Er^(3+),which includes not only the self-quenching of Yb^(3+),but also the dominance in the Yb^(3+)-Er^(3+)*** this finding may provide new ideas for revealing the reasons for the diminished luminescence of highly doped upconversion nanoparticles and thus for enhancing luminescence.

关键词： upconversion luminescence lanthanide ion core-shell nanoparticles concentration quenching cross-relaxation

A Unified Motion Generation Approach for Quadruped L-S Walk and Trot Gaits Based on Linear Model Predictive Control

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Journal of Bionic Engineering 2024年第4期21卷 1707-1719页

作者： Yapeng Shi Zhicheng He Xiaokun Leng Songhao Piao lining sun Harbin Institute of Technology No.92 West Dazhi StreetHarbin150001HeilongjiangChina Yanshan University No.438 West Hebei AvenueQinhuangdao066004HebeiChina

The goal of this paper is to develop a unified online motion generation scheme for quadruped lateral-sequence walk and trot gaits based on a linear model predictive control ***,the dynamics of the linear pendulum model is formulated over a predictive horizon by dimensional *** gait pattern conversion,the lateral-sequence walk and trot gaits of the quadruped can be regarded as unified biped gaits,allowing the dynamics of the linear inverted pendulum model to serve quadruped motion *** addition,a simple linearization of the center of pressure constraints for these quadruped gaits is developed for linear model predictive control ***,the motion generation problem can be solved online by quadratic programming with foothold *** is demonstrated that the proposed unified scheme can generate stable locomotion online for quadruped lateral-sequence walk and trot gaits,both in simulation and on *** results show significant performance improvements compared to previous ***,the results also suggest the linearly simplified scheme has the ability to robustness against unexpected disturbances.

关键词： Motion generation Gait pattern conversion Model predictive control Quadruped locomotion

Reinforcement Learning Navigation for Robots Based on Hippocampus Episode Cognition

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Journal of Bionic Engineering 2024年第1期21卷 288-302页

作者： Jinsheng Yuan Wei Guo Zhiyuan Hou Fusheng Zha Mantian Li Pengfei Wang lining sun State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

Artificial intelligence is currently achieving impressive success in all ***,autonomous navigation remains a major challenge for *** learning is used for target navigation to simulate the interaction between the brain and the environment at the behavioral level,but the Artificial Neural Network trained by reinforcement learning cannot match the autonomous mobility of humans and *** hippocampus–striatum circuits are considered as key circuits for target navigation planning and *** paper aims to construct a bionic navigation model of reinforcement learning corresponding to the nervous system to improve the autonomous navigation performance of the *** ventral striatum is considered to be the behavioral evaluation region,and the hippocampal–striatum circuit constitutes the position–reward *** this paper,a set of episode cognition and reinforcement learning system simulating the mechanism of hippocampus and ventral striatum is constructed,which is used to provide target guidance for the robot to perform autonomous *** with traditional methods,this system reflects the high efficiency of learning and better Environmental *** research is an exploration of the intersection and fusion of artificial intelligence and neuroscience,which is conducive to the development of artificial intelligence and the understanding of the nervous system.

关键词： Episode cognition Reinforcement learning Hippocampus Robot navigation

Multi-sensor control for precise assembly of optical components

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Chinese Journal of Aeronautics 2014年第3期27卷 613-621页

作者： Ma Li Rong Weibin sun lining School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Robotics and System Harbin Institute of Technology

In order to perform an optical assembly accurately, a multi-sensor control strategy is developed which includes an attitude measurement system, a vision system, a loss measurement system and a force sensor. A 3-DOF attitude measuring method using linear variable differential transformers （LVDT） is designed to adjust the relation of position and attitude between the spher- ical mirror and the resonator. A micro vision feedback system is set up to extract the light beam and the diaphragm, which can achieve the coarse positioning of the spherical mirror in the optical assembly process. A rapid self-correlation method is presented to analyze the spectrum signal for the fine positioning. In order to prevent the damage of the optical components and realize sealing of the resonator, a hybrid force-position control is constructed to control the contact force of the optical components. The experimental results show that the proposed multi-sensor control strategy succeeds in accomplishing the precise assembly of the optical components, which consists of parallel adjustment, macro coarse adjustment, macro approach, micro fine adjustment, micro approach and optical contact. Therefore, the results validate the multi-sensor control strategy.

关键词： Assembly Attitude measurement Force control Multi-sensor Vision

Magnetic Actuated Shape-memory Helical Microswimmers with Programmable Recovery Behaviors

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Journal of Bionic Engineering 2021年第4期18卷 799-811页

作者： Fu Zhao Weibin Rong Lefeng Wang lining sun State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin150080China

Inspired by bacterial flagella in nature,magnetic helical microswimmer is an ideal model to perform complex task in a low Reynolds number *** Memory Polymers(SMPs)with desirable properties are considered as one of the most preferred options for the development of small-scale ***,fabricating and programming strategies are still ***,we report an approach to fabricate helical microswimmers based on thermoplastic SMP(polylactic acid).Melt-spun polylactic acid fibers containing magnetic particles were enwound to form helical *** shape recovery behaviors were programmed by annealing and *** forms of helical microswimmers(constant-helix-angle conical helix,constant-pitch conical helix,and straight helix)with controlled morphological parameters were *** obtained microswimmers showed 3D locomotion capability under rotating magnetic *** maximum swimming velocity of microswimmers was nearly six body lengths per second,and the near-wall swimming of conical helixes along their sharp end exhibited a smaller ***,we demonstrated programmed shape-switching processes(spring-like contraction and elongation,coiling and uncoiling)and self-repairing of the *** demonstrations of potential applications,tasks of mobile microstent,cargo delivery,and minimally invasive injection were carried *** multifunctional shape-memory microswimmers have immense potential in a variety of applications.

关键词： helical microrobot magnetic actuation Shape Memory Polymer(SMP) polylactic acid magnetic particles

Design of a control system for a macro-micro dual-drive high acceleration high precision positioning stage for IC packaging

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Science China(Technological Sciences) 2009年第7期52卷 1858-1865页

作者： LIU YanJie LI Teng sun lining State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

A macro-micro dual-drive positioning system showing good potential for high acceleration and high precision positioning required in IC packaging applications is devised in this paper. The dual-drive positioning stage uses a VCM (voice coil motor) driven macro positioning stage and a PZT piezo-electric driven micro positioning stage. The coupling characteristics of the system are analyzed to produce a control structure with a micro positioning stage that can dynamically compensate for the positioning error produced by the macro positioning stage. Models of the two positioning stages are described. The models cover both the mechanism and the actuator. For the macro positioning stage, friction characteristics are taken into account, and a controller with an LQG (linear-quadratic-Gaussian) control algorithm combining a feed-forward compensation algorithm is derived. A PID controller is used to control the micro positioning stage. Detailed designs are derived for the proposed approach, and the performance is validated by simulation.

关键词： macro-micro dual-drive positioning stage control system friction LQG

Digital microfluidics： A promising technique for biochemical applications

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Frontiers of Mechanical Engineering 2017年第4期12卷 510-525页

作者： He WANG Liguo CHEN lining sun Robotics and Microsystems Center Soochow University Soochow215006 China School of Mechanical Engineering Henan University of EngineeringZhengzhou 451191 China

Digital microfluidics （DMF） is a versatile microfluidics technology that has significant application potential in the areas of automation and miniaturization. In DME discrete droplets containing samples and reagents are controlled to implement a series of operations via electrowetting-on-dielectric. This process works by apply- ing electrical potentials to an array of electrodes coated with a hydrophobic dielectric layer. Unlike microchannels, DMF facilitates precise control over multiple reaction processes without using complex pump, microvalve, and tubing networks. DMF also presents other distinct features, such as portability, less sample consumption, shorter chemical reaction time, flexibility, and easier combination with other technology types. Due to its unique advantages, DMF has been applied to a broad range of fields （e.g., chemistry, biology, medicine, and environment）. This study reviews the basic principles of droplet actuation, configuration design, and fabrication of the DMF device, as well as discusses the latest progress in DMF from the biochemistry perspective.

关键词： digital microfluidics electrowetting on dielec-tric discrete droplet biochemistry

Lanthanide-doped heterostructured nanocomposites toward advanced optical anti-counterfeiting and information storage

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Light(Science & Applications) 2022年第6期11卷 1264-1273页

作者： Yao Xie Yapai Song Guotao sun Pengfei Hu Artur Bednarkiewicz lining sun Department of Physics College of SciencesShanghai UniversityShanghai 200444China Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Research Center of Nano Science and Technology College of SciencesShanghai UniversityShanghai 200444China Instrumental Analysis&Research Center Shanghai UniversityShanghai 200444China Institute of Low Temperature and Structure Research Polish Academy of Sciences50-422 Wroc?awPoland

The continuously growing importance of information storage,transmission,and authentication impose many new demands and challenges for modern nano-photonic materials and information storage technologies,both in security and storage ***,luminescent lanthanide-doped nanomaterials have drawn much attention in this field because of their photostability,multimodal/multicolor/narrowband emissions,and long luminescence ***,we report a multimodal nanocomposite composed of lanthanide-doped upconverting nanoparticle and EuSe semiconductor,which was constructed by utilizing a cation exchange *** nanocomposite can emit blue and white light under 365 and 394 nm excitation,***,the nanocomposites show different colors under 980 nm laser excitation when the content of Tb3+ions is changed in the upconversion ***,the time-gating technology is used to filter the upconversion emission of a long lifetime from Tb3+or Eu3+,and the possibilities for modulating the emission color of the nanocomposites are further *** on the advantage of multiple tunable luminescence,the nanocomposites are designed as optical modules to load optical *** work enables multi-dimensional storage of information and provides new insights into the design and fabrication of next-generation storage materials.

关键词： lanthanide excitation luminescence

Facile synthesis of Er^(3+)/Tm^(3+)co-doped magnetic/luminescent nanosystems for possible bioimaging and therapy applications

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Journal of Rare Earths 2022年第1期40卷 11-19页

作者： Hongyu Liu Jiabei Li Pengfei Hu Songqiang sun Liyi Shi lining sun Research Center of Nano Science and Technology College of SciencesShanghai UniversityShanghai 200444China Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Institute of Nanochemistry and Nanobiology School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China Instrumental Analysis&Research Center Shanghai UniversityShanghai 200444China

Manganese-zinc ferrite is a kind of very important magnetic ferrite *** properties of wide absorption band,sensitivity to ultraviolet(UV)light and tumor H_(2)O_(2) promise it to be possibly used as a photothermal therapy(PTT),photodynamic therapy(PDT)and chemodynamic therapy(CDT)*** on the unique advantages of rare-earth doped nanoparticles,an Er^(3+),Tm^(3+)co-doped upconversion-mediated nanosystem with manganese-zinc ferrite shell(named as UCNPS@M)was developed through a facile thermal co-decomposition *** final nanosystems were surface-modified by using dopamine hydrochloride(DA)in order to warrant good biocompatibility(named as UCNPS@M@DA).Under irradiation of near-infrared(NIR)light,UCNPS emit both ultraviolet and visible *** UV light is mostly abso rbed by manga nese-zinc ferrite shell to produce reactive oxygen species(ROS),which is essential to the potential PDT and CDT effect of nanosystems,and at the same time,Mn_(0.5)Zn_(0.5)Fe2O_(4) can further react with H_(2)O_(2) to promote the efficiency of *** is expected that UCNPS@M@DA can act as upconversion luminescence imaging guidance due to the visible emission from *** addition,the energy absorbed by the nanosystems can be transferred to heat to realize photothermal ***,UCNPS@M@DA was successfully applied as a T_(1)/T_(2)-weighted magnetic resonance imaging(MRI)contrast agent due to the existence of Gd,Mn,and Fe *** light of the upconversion luminescence(UCL)imaging from the UCNPS as well as potential PTT,PDT,CDT effect mentioned above,this work provides a possibility to realize cancer multi-model bioimaging guided treatment by using an all-in-one diagnosis and therapy nanosystem through a simple yet powerful strategy.

关键词： Manganese-zinc ferrite Upconversion nanoparticles Photothermal effect Reactive oxygen species Good biocompatibility Rare earths

LOADS INFLUENCE ANALYSIS ON NOVEL HIGH PRECISION FLEXURE PARALLEL POSITIONER

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 37-40页

作者： sun lining DONG Wei DU Zhijiang Robotics Institute Harbin Institute of Technology Harbin 150001 China

A large workspace flexure parallel positioner system is developed, which can attain sub-micron scale accuracy over cubic centimeter motion range for utilizing novel wide-range flexure hinges instead of the conventional mechanism joints. Flexure hinges eliminate backlash and friction, but on the other hand their deformation caused by initial loads influences the positioning accuracy greatly, so discussions about loads＇ influence analysis on this flexure parallel positioner is very necessary. The stiffness model of the whole mechanism is presented via stiffness assembly method based on the stiffness model of individual flexure hinge, And the analysis results are validated by the finite element analysis （FEA） simulation and experiment tests, which provide essential data to the practical application of this positioner system.

关键词： Flexure hinge Parallel positioner Stiffness analysis Finite element analysis (FEA)