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运行时间周期化工业机器人模型迭代寻优NURBS轨迹插补

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控制理论与应用 2024年第2期41卷 331-341页

作者：杨博涵邢燕好张佳张华良张建鹏沈阳工业大学信息科学与工程学院辽宁沈阳110870 中国科学院网络化控制系统重点实验室辽宁沈阳110016 中国科学院沈阳自动化研究所辽宁沈阳110016 中国科学院机器人与智能制造创新研究院辽宁沈阳110169 西北工业集团有限公司陕西西安710043

为满足工业机器人高精度复杂曲线运动的需求,本文提出运行时间周期化工业机器人模型迭代寻优NURBS轨迹插补算法.首先,根据轨迹最大轮廓误差和机器人动力学特性对曲线分段.随后,提出优化回溯算法,使各子曲线段均可用S曲线加减速规划.之后... 详细信息

为满足工业机器人高精度复杂曲线运动的需求,本文提出运行时间周期化工业机器人模型迭代寻优NURBS轨迹插补算法.首先,根据轨迹最大轮廓误差和机器人动力学特性对曲线分段.随后,提出优化回溯算法,使各子曲线段均可用S曲线加减速规划.之后,为保证机器人在进给速度极小值处不超速,将各加减速阶段运行时间调整为插补周期的整数倍,并对子曲线段衔接处速度平滑处理.最后,提出模型迭代寻优曲线插补,大大降低了速度波动率.仿真试验表明,该方法插补轨迹的各项指标均满足要求且最大速度波动率仅为0.000099%.真机试验也验证了该方法可有效减小轨迹误差.

关键词：工业机器人 NURBS曲线运行时间周期化优化回溯算法模型迭代寻优

抗黑色素瘤分化抗原5抗体阳性皮肌炎合并间质性肺疾病亚型:临床特征与预后分析

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中日友好医院学报 2024年第1期38卷 3-7页

作者：杨阚波卢昕王国春陈芳中日友好医院风湿免疫内科 100029

目的:探讨抗黑色素瘤分化抗原5(MDA5)抗体阳性皮肌炎(DM)并发间质性肺疾病(ILD)患者的临床特征及预后差异。方法:回顾性分析2012年1月—2021年7月收治的272例MDA5阳性DM-ILD患者。分为3组:组1为治疗前确诊为快速进展性ILD(RPILD),组2患... 详细信息

目的:探讨抗黑色素瘤分化抗原5(MDA5)抗体阳性皮肌炎(DM)并发间质性肺疾病(ILD)患者的临床特征及预后差异。方法:回顾性分析2012年1月—2021年7月收治的272例MDA5阳性DM-ILD患者。分为3组:组1为治疗前确诊为快速进展性ILD(RPILD),组2患者治疗后发生RPILD,组3为病情较轻的ILD。评估3组患者临床特征、治疗策略及糖皮质激素剂量等预后因素。结果:共纳入219例患者。组1患者病程短,发热、抗核抗体和抗Ro-52阳性率高,ESR、CRP水平高,CD3、CD4 T细胞计数低,与另2组患者差异有统计学意义(P<0.05)。组1患者治疗后4~8周死亡率高,组2患者12周后死亡率升高,组3死亡率最低,3组间死亡时间分布的差异有统计学意义(P<0.05)。Cox分析显示,发病年龄、乳酸脱氢酶水平、未用免疫抑制剂和初始激素用量是组1患者预后的独立危险因素,静脉注射免疫球蛋白是组2的保护因素(P<0.05)。组2多数患者肺部恶化时发现病原体。结论:MDA5阳性DM-ILD患者临床表现和预后存在显著异质性,RPILD患者并不能从大剂量激素治疗中获益。

关键词：抗黑色素瘤分化抗原5抗体快速进展间质性肺疾病临床异质性皮肌炎糖皮质激素

Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research International 2024年第1期31卷 143-156页

作者： An-gang Ning yang Liu Rui Gao Stephen Yue Ming-bo Wang han-jie Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials Engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were *** results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,*** the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 ***,prior-austenite grain size increases with the increase in austenitizing *** kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami ***,the comprehensive strengthening of the H13 steel was discussed in *** results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the *** suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high *** the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density *** dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening

Neurophysiological, histological, and behavioral characterization of animal models of distraction spinal cord injury: a systematic review

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Neural Regeneration Research 2024年第3期19卷 563-570页

作者： bo han Weishi Liang Yong Hai Duan Sun Hongtao Ding Yihan yang Peng Yin Department of Orthopedics Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal *** the increased degree and duration of distraction,spinal cord injuries become more serious in terms of their neurophysiology,histology,and *** few studies have been published on the specific characteristics of distraction spinal cord *** this study,we systematically review 22 related studies involving animal models of distraction spinal cord injury,focusing particularly on the neurophysiological,histological,and behavioral characteristics of this *** addition,we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord *** provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research,and provide reference guidelines for the clinical diagnosis and treatment of this disease.

关键词： animal models behavior distraction heterogeneity histology mechanism neurophysiology spinal cord injury systematic review tension

Targeting ferroptosis and ferritinophagy:new targets for cardiovascular diseases

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 1-22页

作者： Yi LUAN yang yang Ying LUAN Hui LIU han XING Jinyan PEI Hengdao LIU bo QIN Kaidi REN Clinical Systems Biology Research Laboratories Translational Medicine Centerthe First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China State Key Laboratory for Artificial Microstructures and Mesoscopic Physics School of PhysicsPeking UniversityBeijing100871China School of Laboratory Medicine Xinxiang Medical UniversityXinxiang453003China Quality Management Department Henan No.3 Provincial People’s HospitalZhengzhou450052China Department of Cardiology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China Center for Translational Medicine the First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China Department of Pharmacy the First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China Henan Key Laboratory of Precision Clinical Pharmacy Zhengzhou UniversityZhengzhou450052China Henan Engineering Research Center for Application&Translation of Precision Clinical Pharmacy Zhengzhou UniversityZhengzhou450052China

Cardiovascular diseases(CVDs)are a leading factor driving mortality ***,an essential trace mineral,is important in numerous biological processes,and its role in CVDs has raised broad discussion for ***-mediated cell death,namely ferroptosis,has attracted much attention due to its critical role in cardiomyocyte damage and ***,ferritinophagy is the upstream mechanism that induces ferroptosis,and is closely related to *** review aims to delineate the processes and mechanisms of ferroptosis and ferritinophagy,and the regulatory pathways and molecular targets involved in ferritinophagy,and to determine their roles in ***,we discuss the possibility of targeting ferritinophagy-induced ferroptosis modulators for treating ***,this review offers some new insights into the pathology of CVDs and identifies possible therapeutic targets.

关键词： Cardiovascular disease Iron Ferroptosis Ferritinophagy Therapeutic target

Strength characteristics of modified polypropylene fiber and cement-reinforced loess

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Journal of Central South University 2017年第3期24卷 560-568页

作者： yang bo-han Department of Airfield and Building Engineering Air Force Engineering University Xi'an 710038 China PLA Unit 95616 Qionglai 611500 China

The reinforcement and stabilization of loess soil are duscussed by using fibers as the reinforcement and cement as the stabilization *** study the strength characteristics of loess soil reinforced by modified polypropylene(MPP) fiber and cement,samples were prepared with six different fiber contents,three different cement contents,three different curing periods and three kinds of fiber *** samples were tested under submergence and non-submergence conditions for the unconfined compressive strength(UCS),the splitting tensile strength and the compressive resilient *** results indicated that combined reinforcement by PP fiber and cement could significantly improve the early strength of loess to 3.65–5.99 MPa in three *** an increase in cement content,the specimens exhibited brittle ***,the addition of fibers gradually modified the mode of fracture from brittle to ductile to *** optimal dosage of fiber to reinforce loess was in the range of 0.3%–0.45% and the optimum fiber length was 12 mm,for which the unconfined compressive strength and tensile strength reached their *** on the analysis of failure properties,cement-reinforced loess specimens were susceptible to brittle damage under pressure,and the effect of modified polypropylene fiber as the connecting "bridge" could help the specimens achieve a satisfactory level of ductility when under pressure.

关键词： fiber-reinforced soil cement-stabilized soil loess mechanical properties fracture characteristics

Early-stage latent thermal failure of single-crystal Ni-rich layered cathode

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Journal of Energy Chemistry 2024年第9期96卷 578-587页

作者： Xiao han Ruoyu Xu Yan Li yang Ding Manchen Zhang bo Wang Xiaoxing Ke Manling Sui Pengfei Yan Beijing Key Laboratory of Microstructure1nd Property of Solids Faculty of Materials1nd ManufacturingBeijing University of TechnologyBeijing 100124China Watt Laboratory Central Research InstituteHuawei Technologies Co.LTDShenzhen 518129GuangdongChina

High nickel content worsens the thermal stability of layered cathodes for lithium-ion batteries,raising safety concerns for their *** understanding the thermal failure process can offer valuable guidance for material optimization on thermal stability and new opportunities in monitoring battery thermal runaway(TR).Herein,this work comprehensively investigates the thermal failure process of a single-crystal nickel-rich layered cathode and finds that the latent thermal failure starts at∼120℃far below the TR temperature(225℃).During this stage of heat accumulation,sequential structure transition is revealed by atomic resolution electron microscopy,which follows the layered→cation mixing layered→LiMn_(2)O_(4)-type spinel→disordered spinel→rock *** progression occurs as a result of the continuous migration and densification of transition metal *** transition generates gaseous oxygen,initially confined within the isolated closed pores,thereby not showing any thermal failure phenomena at the *** temperature leads to pore growth and coalescence,and eventually to the formation of open pores,causing oxygen gas release and weight loss,which are the typical TR *** highlight that latent thermal instability occurs before the macro-level TR,suggesting that suppressing phase transitions caused by early thermal instability is a crucial direction for material *** findings can also be used for early warning of battery thermal runaway.

关键词： Thermal runaway Nickel-rich layered cathode Transmission electron microscopy Lithium-ion battery Phase transition

Nrf2-mediated ferroptosis of spermatogenic cells involved in male reproductive toxicity induced by polystyrene nanoplastics in mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 307-323页

作者： Xufeng FU hang han Hong yang bo XU Wenjie DAI Ling LIU Tiantian HE Xing DU Xiuying PEI Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education School of Basic Medical SciencesNingxia Medical UniversityYinchuan 750004China Key Laboratory of Reproduction and Genetics in Ningxia Ningxia Medical UniversityYinchuan 750004China

Microplastics(MPs)and nanoplastics(NPs)have become hazardous materials due to the massive amount of plastic waste and disposable masks,but their specific health effects remain *** this study,fluorescence-labeled polystyrene NPs(PS-NPs)were injected into the circulatory systems of mice to determine the distribution and potential toxic effects of NPs in ***,whole-body imaging found that PS-NPs accumulated in the testes of ***,the toxic effects of PS-NPs on the reproduction systems and the spermatocytes cell line of male mice,and their mechanisms,were *** oral exposure to PS-NPs,their spermatogenesis was affected and the spermatogenic cells were *** spermatocyte cell line GC-2 was exposed to PS-NPs and analyzed using RNA sequencing(RNA-seq)to determine the toxic mechanisms;a ferroptosis pathway was found after PS-NP *** phenomena and indicators of ferroptosis were then determined and verified by ferroptosis inhibitor ferrostatin-1(Fer-1),and it was also found that nuclear factor erythroid 2-related factor 2(Nrf2)played an important role in spermatogenic cell ferroptosis induced by ***,it was confirmed in vivo that this mechanism of Nrf2 played a protective role in PS-NPs-induced male reproductive *** study demonstrated that PS-NPs induce male reproductive dysfunction in mice by causing spermatogenic cell ferroptosis dependent on Nrf2.

关键词： Polvstyrene nanoplastics(PS-NPs) Reproductive toxicity Ferroptosis Nuclear factor ervthroid 2-related factor 2(Nrf2)

A solution using only electromagnetic coils for relative pose control in satellite docking

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Chinese Journal of Aeronautics 2024年第3期37卷 258-281页

作者： Guangzheng RUAN Lijian WU bo WANG Yaobing WANG Runqi han College of Electrical Engineering Zhejiang UniversityHangzhou 310012China Beijing Institute of Spacecraft System Engineering Beijing 100094China

This paper proposes an electromagnetic coil topology and its control strategy,which can be incorporated into the electromagnetic docking device to achieve relative pose control in satellite *** target satellite has a main coil;the chaser satellite possesses a main coil of the same size accompanied by six and four evenly arranged secondary coils inside and outside the main coil,*** coil on the target satellite is DC energized,while the currents in the coils of the chaser satellite are *** remove the coupling between the pitch/yaw torque and translational force,the internal and external secondary coils of the chaser satellite interact with the main coil of the target satellite to perform the control of relative pitch/yaw and relative translation,respectively,so relative pose control can be *** torque and force vectors exerted by the secondary coils of the chaser satellite are synthesized onto the pitch and yaw axes of the body *** to their spatial composition relationship,the formulas are proposed,which obtain the magnetic moment vectors of the coils from the set torques and *** controllers regulating pitch/yaw,translation,and distance utilize a three-loop cascaded structure that consists of an outer position loop,a middle velocity loop and an inner current *** control strategy is verified by dynamics simulation.

关键词： Electromagnetic docking 6 degree of freedom Relative pose control Coil array Far field model Motion decoupling