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Dynamic modeling of a 6-degree-of-freedom Stewart platform driven by a permanent magnet synchronous motor

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第10期11卷 751-761页

作者： Qiang MENG Tao ZhanG Jing-feng HE Jing-yan SONG jun-wei han Department of Automation Tsinghua University Beijing 100084 China School of Mechatronic Engineering Harbin Institute of Technology Harbin 150001 China

For an electrical six-degree-of-freedom Stewart platform,it is difficult to compute the equivalent inertia of each motor in real time,as the inertia is *** this study,an analysis using Kane's equation is undertaken of the driven torque of the movements of motor systems(including motor friction,movements of motor systems along with the actuators,rotation around axis of rotors and snails),as well as driven torque of the platform and *** electromagnetic torque was calculated according to vector-controlled permanent magnet synchronous motor(PMSM) *** equalizing the driven torque and electromagnetic torque,a model was *** method,taking into consideration the influence of counter electromotive force(EMF) and motor friction,could be applied to the real-time dynamic control of the platform,through which the calculation of the time-varying equivalent inertia is ***,simulations with typically desired trajectory inputs are presented and the performance of the Stewart platform is *** this approach,the multi-body dynamics of the electrical Stewart platform is better understood.

关键词： Dynamics analysis Six-degree-of-freedom Stewart platform Kane’s equation Permanent magnet synchronous motor(PMSM) Vector control

Abdominal drainage systems in modified piggyback orthotopic liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 99-102页

作者： Rui Tang Li-han Yu jun-wei han Jing-Yi Lin Jin-Jie An Qian Lu Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineInstitute for Precision MedicineTsinghua UniversityBeijing 102218China Department of Hepatopancreatobiliary Surgery Affiliated Hospital of Qinghai UniversityXining 810001China

To the Editor:Whether orthotopic liver transplantation requires the placement of an abdominal drainage system is a controversial topic.A number of studies have suggested that prophylactic placement of abdominal drainage systems do not improve the diagnostic rate of complications such as bile leakage and hemorrhage after liver transplantation,even increased the risk of infection[1–3].However,there is no uniform standard for the selection of drainage tube and how to place the drainage tube in orthotopic liver *** types and placement modes of the drainage tubes used in each center are *** adequate drainage is not possible,it may affect the drainage efficiency,which may lead to the misunderstanding that“it is unnecessary to place the drainage tube”.Herein we aimed to explore the most efficient abdominal drainage in modified piggyback orthotopic liver transplantation,based on the types and placement modes of drainage tubes in our clinical practice.

关键词： liver orthotopic drainage

Effectiveness of toric soft contact lenses for vision correction in patients with different degrees of astigmatism: a real-world study

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International Journal of Ophthalmology(English edition) 2023年第11期16卷 1845-1853页

作者： Guo-Yun Zhang Lu Ye Wen-jun Wang Yi-Ming Guo jun-han wei Mei-Xia Ren Shaanxi Eye Hospital Xi’an People’s Hospital(Xi’an Fourth Hospital)Xi’an 710004Shaanxi ProvinceChina

AIM:To assess the visual correction of patients with different degrees of astigmatism with toric soft contact lenses(TSC).METHODS:It was a real-world study with prospective and single-arm design.A total of 384 patients with astigmatism who came for TSC fitting and alignment from November 2022 to January 2023 were *** to the difference in astigmatism,patients were divided into groups A(cylinder degree:-0.75 to-0.50 D),B(cylinder degree:-1.75 to-1.00 D)and C(cylinder degree≤-2.00 D),and followed up on the day of wear,1wk,1 and 3mo,mainly to observe visual acuity,refraction,lens fit,visual quality and comfort at 1wk after *** visual acuity success rate and the overall success rate of the fitting were evaluation indicators(taking into account the four dimensions of visual acuity,fitting,quality of vision and comfort).The visual acuity success rate was calculated by taking“corrected visual acuity with contact lenses is no less than 1 line or better than best spectacle-corrected visual acuity”(*** visual acuity with contact lenses is 1 line below,equal to,one line above or more than best spectaclecorrected visual acuity)as the criterion for visual success,and the the overall success rate of the fitting was calculated by using the comprehensive indicators(visual acuity,fit,visual quality,comfort)to meet certain conditions as the judgment criteria for successful ***:After 1wk of wearing TSC,the visual acuity success rates of patients were 100%(207/207),98.58%(139/141)and 97.22%(35/36)in the three groups,respectively,with residual cylinder closed to *** acceptability of the lens fitting was over 95%;the incidence of adverse visual symptoms was within 10%and the comfort acceptability was over 97%.The overall success rate of fitting for patients with high,medium and low astigmatism was 93.72%(194/207),90.78%(128/141)and 88.89%(32/36),***:TSC(model:G&G POP·CT)are effective in correcting astigmatism in patients with

关键词： toric soft contact lenses astigmatism visual acuity

FOOD SAFETY CONTROL SYSTEM IN CHINA

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China Standardization 2007年第4期52卷 2-9页

作者： Liu wei-jun wei Yi-min han jun Luo Dan Pan Jia-rong Institute of Agro-Food Science and Technology Chinese Academy of Agricultural Sciences Department for Rural Economy Development Research Center of the State Council of China 　　　

Most countries have expended much effort to develop food safety control systems to ensure safe food supplies within their borders. China, as one of the world's largest food producers and consumers, pays a lot of attention to food safety issues. In recent years, China has taken actions and implemented a series of plans in respect to food safety. Food safety control systems including regulatory, supervisory, and science and technology systems, have begun to be established in China. Using, as a base, an analysis of the current Chinese food safety control system as measured against international standards, this paper discusses the need for China to standardize its food safety control system. We then suggest some policies and measures to improve the Chinese food safety control system.

关键词： Regulatory system Supervision system Science and technology system Food safety control system

Adsorption and leaching behaviors of chalcopyrite by two extreme thermophilic archaea

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Transactions of Nonferrous Metals Society of China 2018年第12期28卷 2538-2544页

作者： Yu-ting LIANG jun-wei han Chen-bing AI Wen-qing QIN School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

The adsorption and leaching of chalcopyrite by two extreme thermophilic archaea(*** and ***)and their mixture were *** results revealed that the chalcopyrite leaching rate of *** was slightly higher than that of ***;the mixed system showed the highest *** structure analysis during the leaching process showed that *** was maintained in a predominant ***,the proportion of *** in the community increased during *** concentrations,which increased faster in the mixed system than in the single-organism systems during later stages,was related to the change of *** in the *** parameter analysis revealed no competitive adsorption between these two thermophilic ***,qPCR(quantitative polymerase chain reaction)confirmed that adsorption was promoted between *** and *** during mixed *** findings can improve our understanding of the adsorption behaviors of mixed extreme microbial populations on mineral surfaces.

关键词： thermophilic archaea A.brierleyi S.metallicus chalcopyrite adsorption leaching

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang han Jia Tuo Liu Yuzhen Yang jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

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响应曲面法优化从废旧LED中浸出有价金属

Transactions of Nonferrous Metals Society of China 2023年第3期33卷 938-950页

作者：魏徐一高永峰韩俊伟王勇伟覃文庆中南大学资源加工与生物工程学院长沙410083 Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 1H9Canada

通过热解和浸出工艺从废旧发光二极管(LEDs)中回收有价金属。通过对热解后的LED预先筛分可回收98.16%Ga和99.54%Y。采用单因素试验和响应曲面法研究不同浸出条件对铁、铜和银浸出的影响。利用无氧化剂H_(2)SO_(4)浸出法从废旧LED中选择... 详细信息

通过热解和浸出工艺从废旧发光二极管(LEDs)中回收有价金属。通过对热解后的LED预先筛分可回收98.16%Ga和99.54%Y。采用单因素试验和响应曲面法研究不同浸出条件对铁、铜和银浸出的影响。利用无氧化剂H_(2)SO_(4)浸出法从废旧LED中选择性回收约90.15%Fe,Fe浸出渣通过添加HNO_(3)浸出可以回收99.55%Cu和99.36%Ag。XRD和SEM-EDS分析证实,所开发的工艺可以高效地从废旧LED中浸出Fe和Cu。

关键词：酸浸金属回收响应曲面法废旧发光二极管

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Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man han Deyang Zeng wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration

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Neural Regeneration Research 2025年第5期20卷 1364-1376页

作者： Ronglin han Lanxin Luo Caiyan wei Yaru Qiao Jiming Xie Xianchao Pan Juan Xing Department of Pathophysiology School of Basic Medical SciencesSouthwest Medical UniversityLuzhouSichuan ProvinceChina Department of Medicinal Chemistry School of PharmacySouthwest Medical UniversityLuzhouSichuan ProvinceChina

Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering.

关键词： alginate axon growth biomaterials extracellular matrix neural repair neurons neuroregeneration polyacrylamide polydimethylsiloxane stiffness