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Acta Mechanica Solida Sinica 2014年第5期27卷 486-495页

作者： Peng Lan Zuqing Yu Liang Du Nianli Lu School of mechatronic engineering Harbin Institute of Technology

This investigation is intended to develop a computer procedure for the integration of NURBS geometry and the rational absolute nodal coordinate formulation （RANCF） finite element analysis. A linear transformation is given that can be used to convert the NURBS curve to RANCF cable element mesh retaining the same geometry and the same degree of continuity, including the discussion of continuity control and mesh refinement. The green strain tensor is used to establish the nonlinear dynamic equations with numerical examples to demonstrate the use of the procedure in the dynamic analysis of flexible bodies.

关键词： finite element method rational absolute nodal coordinate formulation (RANCF),NURBS mesh refinement

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

High‑Entropy Electrode Materials:Synthesis,Properties and Outlook

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Nano-Micro Letters 2025年第1期17卷 472-506页

作者： Dongxiao Li Chang Liu Shusheng Tao Jieming Cai Biao Zhong Jie Li Wentao Deng Hongshuai Hou Guoqiang Zou Xiaobo Ji College of Chemistry and Chemical engineering Central South UniversityChangsha 410083People’s Republic of China School of Chemistry and Chemical engineering Hunan Institute of EngineeringXiangtan 411104People’s Republic of China

High-entropy materials represent a new category of high-performance materials,first proposed in 2004 and extensively investigated by researchers over the past two *** definition of high-entropy materials has continuously *** the last ten years,the discovery of an increasing number of high-entropy materials has led to significant advancements in their utilization in energy storage,electrocatalysis,and related domains,accompanied by a rise in techniques for fabricating high-entropy electrode ***,the research emphasis has shifted from solely improving the performance of high-entropy materials toward exploring their reaction mechanisms and adopting cleaner preparation ***,the current definition of high-entropy materials remains relatively vague,and the preparation method of high-entropy materials is based on the preparation method of single metal/low-or medium-entropy *** should be noted that not all methods applicable to single metal/low-or medium-entropy materials can be directly applied to high-entropy *** this review,the definition and development of high-entropy materials are briefly ***,the classification of high-entropy electrode materials is presented,followed by a discussion of their applications in energy storage and catalysis from the perspective of synthesis ***,an evaluation of the advantages and disadvantages of various synthesis methods in the production process of different high-entropy materials is provided,along with a proposal for potential future development directions for high-entropy materials.

关键词： High-entropy Energy storage Electrode materials

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn J.W.So Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon Gregory HBorschel SickKids Research institute Neuroscience and Mental Health ProgramTorontoONCanada institute of Biomaterials and Biomedical engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Dynamics of Forster Energy Transfer in Pyridium Salt-Doped Thin Films

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Chinese Physics Letters 2009年第7期26卷 328-331页

作者：徐登庄小红 Department of Electrical engineering Changzhou Institute of Mechatronic Technology Changzhou 213164 Department of Humanities Changzhou Institute of Mechatronic Technology Changzhou 213164

Properties of photoluminescence and F6rster energy transfer dynamics based on an organic pyridium salt trans-4- [p-（N-Hydroxyethyl-N-methylamino）Styryl]-N-methylpyridinium iodide （ASPI） and organic small molecule Alq3 in PMMA polymeric thin films are investigated by steady-state and time-resolved fluorescent spectra as well as theoretical calculation. The observation of reduced emission intensity and the fluorescent lifetime of Alq3 is demonstrated, while the ASPI emission gradually increases and is finally dominant in the PL spectra with increasing ASPI doping concentration. Such results show that there exists an emcient F6rster energy transfer （FET） from Alq3 to ASPI due to the large spectral overlap between ASP（ absorption and Alq3 emission. The difference between the theoretical FET efficiency and the experimental data is caused by the lower mobility of the Alq3 exciton in the PMMA matrix.

关键词： Soft matter liquids and polymers Condensed matter: electrical magnetic and optical Surfaces interfaces and thin films

Improved single-neuron PID controller for DC motor applied in robot system

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Journal of Beijing institute of Technology 2012年第4期21卷 472-478页

作者：苏晓东罗庆生郅威 School of mechatronic engineering Beijing Institute of Technology

An improved single-neuron proportional integral derivative （ PID ） controller and a new method to build the DC motor system were presented in the article. In the simulation, the robot arm is considered as an external load to DC motor. Both the motor module and the load module are crea- ted in Simulink to achieve simulation results closer to real robot system. In this way, it can well veri- fy the performance of the improved single-neuron PID controller, which is a combined controller of normal PID controller and single-neuron PID controller. Besides, an intelligent switcher can help to realize the function of choosing a better control algorithm according to motor＇ s velocity output. Sim- ulated results confirm the rapid and stable response of the improved PID controller. Moreover, the improved single-neuron PID controller has an excellent ability to overcome the load impact and su- press the jamming signals. At last, a GUI interface platform is built to make the controller easier to be applied in other robot systems.

关键词： robot control system DC motor proportional integral derivative (PID) single-neuron

The effect of the beam shapes on the doubly-clamped piezoelectric energy harvester

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Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1361-1374页

作者： Lei JIN Shiqiao GAO Xiyang ZHANG School of mechatronic engineering Beijing Institute of Technology

For a piezoelectric energy harvester composed of a doubly-clamped beam with arbitrary width shapes and a proof mass, the influence of beam shapes and electrode arrangements on different electric outputs is analyzed. The output performances of piezoelectric energy harvesters with rectangular shape, concave trapezoidal shape, and concave parabolic shape are compared, and an optimization way is given. The experimental results validate the effectiveness of the methods.

关键词： doubly-clamped width shape piezoelectric energy harvester electrode connection

Numerical method for estimation of kinematical parameters for articulated rovers on loose rough terrain

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Journal of Harbin institute of Technology(New Series) 2009年第4期16卷 505-512页

作者：禹鑫燚高海波邓宗全 School of mechatronic engineering Harbin Institute of Technology

Based on the study of passive articulated rover,a complete suspension kinematics model from wheel to inertial reference frame is presented,which uses D-H method of manipulator and presentation with Euler angle of pitch,roll and *** improved contact model is adopted aimed at the loose and rough lunar *** this kinematics model and numerical continuous and discrete Newton's method with iterative factor,the numerical method for estimation of kinematical parameters of articulated rovers on loose and rough terrain is *** demonstrate this numerical method,an example of two torsion bar rocker-bogie lunar rover with eight wheels is *** results show that the numerical method for estimation of kinematical parameters of articulated rovers based on improved contact model can improve the precision of kinematical estimation on loose and rough terrain and decrease errors caused by contact models established based on general hypothesis.

关键词： loose soil kinematical parameters estimation suspension kinematics articulated lunar rover nu merical solving

Study on singularity analysis with differential transform method for 3-RRUR parallel robot based on Jacobian matrix

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Journal of Beijing institute of Technology 2011年第3期20卷 372-378页

作者：董悫蒋志宏黄强 School of mechatronic engineering Beijing Institute of Technology

Parallel robot is used in many different fields nowadays, but the singularity of 3-RRUR parallel robot is more complicated, so a method to analyze the singularity of the 3-RRUR parallel robot is very necessary. First, the Jacobian matrix was built based on the differential transform method through the transfer matrixes between the poles. The connection between the position parameters and singularity condition was built through the analysis of the Jacobian matrix. Second, the effect on the singularity from the position parameters was analyzed, and then the singularity condition was confirmed. The effect on the singularity condition from position parameters was displayed by the curved surface charts to provide a basic method for the designing of the parallel robot. With this method, the singularity condition could be got when the length of each link is firmed, so it can be judged that if a group of parameters are appropriate or not, and the method also provides warrant for workspace and path planning of the parallel robot.

关键词： Jacobian matrix parallel robot singularity

Dynamics analysis of drawing cables for pipe robot over long distance

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Journal of Harbin institute of Technology(New Series) 2003年第1期10卷 55-59页

作者：邓宗全王少纯胡明姜生源 School of mechatronic engineering Harbin Institute of Technology

Focusing on the speed control problem, this paper presents a study on the stick slip phenomena of cable driven by pipe robot and the critical conditions of stick slip. By dynamics simulation and field experiments, the theoretical analysis has been proved to be practical and valid. The result is of considerable theoretical value in the speed control for pipe robot on receiving and putting line.

关键词： pipe robot cable stick slip phenomena speed control