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Using the Fourier Series Function to Improve the Kinematic Characteristic of Ball-Screw Servo Press Mechanism

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Using the Fourier Series Function to Improve the Kinematic C...

Flexible nanoimprint lithography enables high-throughput manufacturing of bioinspired microstructures on warped substrates for efficient III-nitride optoelectronic devices

第9届中国机构与机器科学应用国际会议(CCAMMS 2011)暨中国轻工机械协会科技研讨会

作者： YAN Hong-Sen kuo ming-sheng Department of Mechanical Engineering Cheng Kung University Department of Mechanical EngineeringCheng Kung University

This paper uses the trajectory function by Fourier series function to improve the kinematic characteristic for a variable-input-speed servo press ball-screw mechanism. The Fourier series of the trajectory function for the servo motor is established to design the performance of a ball-screw mechanism by using feasible mechanism parameters and constraints. An example to improve the maximum peak value of kinematic characteristics of the servo press ball-screw mechanism is analyzed. According to the results of the simulation, the kinematic characteristic is reduced and conformed to the objective design by using the variable input.

关键词： Variable speed input ball screw mechanism Fourier series function servo press

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Science Bulletin 2024年第13期69卷 2080-2088页

作者： Siyuan Cui Ke Sun Zhefu Liao Qianxi Zhou Leonard Jin Conglong Jin Jiahui Hu kuo-sheng Wen sheng Liu shengjun Zhou Center for Photonics and Semiconductors School of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterloo ONN2L 3G1Canada Jiangxi SMTC Semiconductor Co. Ltd.Nanchang 330096China

III-nitride materials are of great importance in the development of modern optoelectronics,but they have been limited over years by low light utilization rate and high dislocation densities in heteroepitaxial films grown on foreign substrate with limited refractive index contrast and large lattice ***,we demonstrate a paradigm of high-throughput manufacturing bioinspired microstructures on warped substrates by flexible nanoimprint lithography for promoting the light extraction *** design a flexible nanoimprinting mold of copolymer and a two-step etching process that enable high-efficiency fabrication of nanoimprinted compound-eye-like Al2O3 microstructure(NCAM)and nanoimprinted compound-eye-like SiO_(2)microstructure(NCSM)template,achieving a 6.4-fold increase in throughput and 25%savings in economic costs over stepper projection *** to NCAM template,we find that the NCSM template can not only improve the light extraction capability,but also modulate the morphology of AlN nucleation layer and reduce the formation of misoriented GaN grains on the inclined sidewall of microstructures,which suppresses the dislocations generated during coalescence,resulting in 40%reduction in dislocation *** study provides a low-cost,high-quality,and high-throughput solution for manufacturing microstructures on warped surfaces of III-nitride optoelectronic devices.

关键词： Flexible nanoimprint lithography Bioinspired Micro-and nano-manufacturing III-nitride epitaxy Optoelectronic devices

PVDF/6H-SiC composite fiber films with enhanced piezoelectric performance by interfacial engineering for diversified applications

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Journal of Materials Science & Technology 2024年第3期170卷 238-245页

作者： Linlin Zhou Tao Yang Chunyu Guo Kang Wang Enhui Wang Laipan Zhu Hailong Wang sheng Cao kuo-Chih Chou Xinmei Hou Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Materials Science Engineering Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China

Piezoelectric silicon carbide(SiC)has been quite attractive due to its superior chemical and physical properties as well as wide potential ***,the inherent brittleness and unsatisfactory piezoelectric response of piezoelectric semiconductors remain the major obstacles to their diversified ***,flexible multifunctional PVDF/6H-SiC composite fiber films are fabricated and utilized to assemble both piezoelectric nanogenerators(PENGs)and stress/temperature/light *** open cir-cuit voltage(V_(oc))and the density of short circuit current(I_(sc))of the PENG based on the PVDF/5 wt%6H-SiC composite fiber films reach 28.94 V and 0.24μA cm^(-2),showing a significant improvement of 240%and 300%compared with that based on the pure PVDF *** effect of 6H-SiC nanoparticles(NPs)on inducing interfacial polarization and stress concentration in composite fiber films is proved by first-principles calculation and finite element *** stress/temperature/light sensors based on the composite fiber film also show high sensitivity to the corresponding *** study shows that the PVDF/6H-SiC composite fiber film is a promising candidate for assembling high-performance energy harvesters and diverse sensors.

关键词： 6H-SiC PVDF Multifunctional composite fiber film Energy harvester Stress/temperature/light sensor

Textured CsPbI_(3)nanorods composite fibers for stable high output piezoelectric energy harvester

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eScience 2024年第5期4卷 150-159页

作者： Tao Yang Dengzhou Jia Bing Xu Yongfei Hao Yanglong Hou Kang Wang Enhui Wang Zhentao Du sheng Cao kuo-Chih Chou Xinmei Hou Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute of Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110000China School of Materials Shenzhen Campus of Sun Yat-Sen UniversityShenzhen 518107China MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured MaterialsGuangxi UniversityNanning 530004China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China

The utilization of piezoelectric nanogenerator(PENG)based on halide perovskite materials has demonstrated significant promise for energy harvesting ***,the challenge of synthesizing halide perovskite materials with both high output performance and stability using a straightforward process persists as a substantial ***,we present the fabrication of CsPbI_(3)nanorods(NRs)exhibiting highly uniform orientation within polyvinylidene fluoride(PVDF)fibers through a simple texture engineering approach,marking the instance of enhancing PENG performance in this *** resultant composite fibers showcase a short-circuit current density(I_(sc))of 0.78μAcm^(-2)and an open-circuit voltage(V_(oc))of 81V,representing a 2.5 fold increase compared to the previously reported highest value achieved without the electric poling *** outstanding output performance is ascribed to the orientation of CsPbI_(3)NRs facilitated by texture engineering and dipole poling via the self-polarization ***,the PENG exhibits exceptional thermal and water stability,rendering it suitable for deployment in diverse and challenging environmental *** findings underscore the significant potential of textured CsPbI_(3)NRs composite fibers for powering low-power consumer electronics,including commercial LEDs and electronic watches.

关键词： Texture engineering CsPbI_(3) Piezoelectric nanogenerator Self-polarization Electrospinning

Longitudinal associations of cardiovascular health and vascular events with incident dementia

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Stroke & Vascular Neurology 2024年第4期9卷 418-428,I0066-I0130页

作者： Ya-Nan Ou Kevin kuo Liu Yang Ya-Ru Zhang Shu-Yi Huang Shi-Dong Chen Yue-Ting Deng Yu Guo Rui-Qi Zhang Bang-sheng Wu Lan Tan Qiang Dong Jian-Feng Feng Wei Cheng Jin-Tai Yu Department of Neurology Qingdao Municipal HospitalQingdao UniversityQingdaoShandongPeople's Republic of China Department of Neurology and National Center for Neurological Disorders Huashan HospitalState Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceShanghai Medical CollegeFudan UniversityShanghaiPeople's Republic of China Institute of Science and Technology for Brain-inspired Intelligence Fudan UniversityShanghaiPeople's Republic of China Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityMinistry of EducationShanghaiPeople's Republic of China

Introduction Evidence supporting cardiovascular diseases could increase the risk of dementia remains fragmented.A comprehensive study to illuminate the distinctive associations across different dementia types is still *** study is sought to:(1)determine the clinical validity of Framingham General Cardiovascular Risk Score(FGCRS)for dementia assessment and(2)examine the associations between cardiovascular diseases and the risk of *** A total of 432079 dementia-free individuals at baseline from UK Biobank were *** Cox proportional hazard models were used to investigate the prospective associations for FGCRS and a series of cardiovascular diseases with all-cause dementia(ACD)and its major components,Alzheimer’s disease(AD)and vascular dementia(VaD).Results During a median follow-up of 110.1 months,4711 individuals were diagnosed with *** was associated with increased risks across the dementia *** stratification analysis,high-risk groups have demonstrated the greatest dementia burdens,particularly to *** 74 traits,9 adverse associations,such as chronic ischaemic heart disease(ACD:HR=1.354;AD:HR=1.269;VaD:HR=1.768),atrioventricular block(ACD:HR=1.562;AD:HR=1.556;VaD:HR=2.069),heart failure(ACD:HR=1.639;AD:HR=1.543;VaD:HR=2.141)and hypotension(ACD:HR=2.912;AD:HR=2.361;VaD:HR=3.315)were *** distinctions were also found,with atrial fibrillation,cerebral infarction,and haemorrhage only associated with greater risks of ACD and *** By identifying distinctive associations between cardiovascular diseases and dementia,this study has established a comprehensive‘mapping’that may untangle the long-standing *** has demonstrated its predictivity beyond cardiovascular diseases burdens,suggesting potential opportunities for implantation.

关键词： cardiovascular diseases supporting

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煤矿钻孔卸压试验台同步控制系统研制

齐齐哈尔大学学报（自然科学版） 2024年第1期40卷 7-11页

作者：姜阔胜周峰安徽理工大学机械工程学院安徽淮南232001

为解决煤矿钻孔卸压实验机理研究,以及双轴系统运动过程中的同步控制误差过大等问题,研制了一种可用于井下钻孔研究的双轴控制试验台,提出了一种结合模糊滑模和交叉耦合控制的同步控制策略。首先,根据钻孔试验台结构和运动特点建立系统... 详细信息

为解决煤矿钻孔卸压实验机理研究,以及双轴系统运动过程中的同步控制误差过大等问题,研制了一种可用于井下钻孔研究的双轴控制试验台,提出了一种结合模糊滑模和交叉耦合控制的同步控制策略。首先,根据钻孔试验台结构和运动特点建立系统简化模型,分析了双轴进给系统的数学模型与不同步误差。然后,设计了模糊滑模自适应交叉耦合控制器,其中单轴采用模糊滑模控制,双丝杠间的同步方式采用模糊自适应PID交叉耦合控制,同时建立了基于LabVIEW的双轴电机控制系统。最后,通过仿真实验对比验证,模糊滑模交叉耦合控制相比于普通交叉耦合控制,同步转速误差<5 r/min,提高了系统的同步控制性能。

关键词：双轴控制模糊滑模交叉耦合 LabVIEW

A Note on Weighted Composition Operators on the Weighted Bergman Space

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Acta Mathematica Sinica,English Series 2015年第6期31卷 947-952页

作者： Lian kuo ZHAO sheng Zhao HOU School of Mathematics and Computer Science Shanxi Normal University School of Mathematics Science Soochow University

This paper gives a note on weighted composition operators on the weighted Bergman space, which shows that for a fixed composition symbol, the weighted composition operators are bounded on the weighted Bergman space on... 详细信息

关键词： Weighted Bergman space weighted composition operator boundedness finite Blaschke product

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苍术生物学特性与繁育技术研究进展

中国中药杂志 2024年第12期49卷 3144-3151页

作者：张成才覃明王红阳郭秀芝闫滨滨张燕周利李阔王升郭兰萍中国中医科学院中药资源中心道地药材品质保障与资源持续利用全国重点实验室北京100700 德兴市中医研究院试验培训基地江西德兴334220 农业农村部中药材生物学与栽培重点实验室北京100700

苍术是菊科苍术属多年生草本植物,是被大众熟知的中药之一。许多研究表明,倍半萜类和多烯炔类化合物是苍术的主要活性物质,尤其是根茎中的苍术素、苍术酮、β-桉叶醇和茅术醇,具有抗病毒、抗炎、降血糖、抗缺氧、保肝和利尿等药理活性... 详细信息

苍术是菊科苍术属多年生草本植物,是被大众熟知的中药之一。许多研究表明,倍半萜类和多烯炔类化合物是苍术的主要活性物质,尤其是根茎中的苍术素、苍术酮、β-桉叶醇和茅术醇,具有抗病毒、抗炎、降血糖、抗缺氧、保肝和利尿等药理活性。随着近年来生物技术的进步,在生物学特性和繁殖培育技术方面的研究取得了较大进展。因此,该文从生物学特性的角度,对苍术形态学特性、细胞遗传学、生态种植、有效成分及组织培养技术方面的研究进行了综述,以期为充分合理地开发苍术资源提供理论依据。

关键词：苍术形态学特征生物学特性有效成分组织培养

All-inorganic transparent Hf_(0.85)Ce_(0.15)O_(2)ferroelectric thin films with high flexibility and stability

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Nano Research 2023年第4期16卷 5065-5072页

作者： sheng-Tao Mo Kai-ming Feng Jing-Lin Pang kuo Ouyang Li-Mei Jiang Qiong Yang Biao Zhang Jie Jiang School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China Hunan Provincial Key Laboratory of Thin Film Materials and Devices Xiangtan UniversityXiangtan 411105China Key Laboratory of Low Dimensional Materials and Application Technology Ministry of EducationXiangtan UniversityXiangtan 411105China

Electronic devices that are transparent and flexible have a wide range of applications in the domains of vital sign parameter monitoring,health management,and so *** memory is a revolutionary nonvolatile memory that is ideal for data storage and processing in transparent flexible electronic *** this study,Ce-doped hafnium oxide ferroelectric thin film is manufactured on mica substrate by the chemical solution deposition with transparent indium tin oxide(ITO)thin films as the bottom *** transmittance of mica/ITO/Hf_(0.85)Ce_(0.15)O_(2)thin film is over 80%.The 2Pr of the transparent flexible Hf_(0.85)Ce_(0.15)O_(2)ferroelectric thin film is increased by about 22.4%and the Ec is reduced by 26.7%compared with those of Hf_(0.85)Ce_(0.15)O_(2)ferroelectric thin film grown on p+-Si *** transparent flexible Hf_(0.85)Ce_(0.15)O_(2)ferroelectric thin film can remain keeping good quality when being bent under±2.5 mm bending ***,degradation of polarization,retention,and endurance performance was not obvious even at a bending radius of 5.0 mm after 104 bending *** research provides a new strategy and an important experimental basis for the development and implementation of transparent flexible ferroelectric memories.

关键词： flexible Hf_(0.85)Ce_(0.15)O_(2)thin films transparent thin films ferroelectric properties