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Science China(Technological Sciences) 2018年第8期61卷 1184-1196页

作者： YANG Rui jin yulin HOU Lei CHEN YuShu School of Astronautics Harbin Institute of Technology School of Energy Science and Engineering Harbin Institute of Technology

The studies on dynamics of a fault bearing system are prevalent in recent years, however, we are studying a completely different frequency range than the one where the bearing faults are best seen. Considering a local defect on outer raceway,a two-degree-of-freedom analytical model of a rigid-rotor ball bearing system is established. Three pulse force models are introduced to simulate the local defect. The frequency domain method—harmonic balance method with alternating frequency/time domain technique (HB-AFT) is used to calculate the response in a large frequency range. By comparing the performance at different frequencies, the fault systems with different defect models and parameters reveal the super-harmonic resonances,and the reasons for this phenomenon are uncovered as well. Finally, the theoretical calculation is verified qualitatively by the experimental results, through comparing the frequency spectrums of the defective bearing rotor system to the fault-free ***, the super-harmonic resonances can be regarded as a dynamic feature. Besides, the obvious super-harmonic resonances indicate the magnification of the harmonics of the "characteristic defect frequency" for outer race in the corresponding speed regions, which may be helpful for the diagnosis of a rotor ball bearing system with a local defect.

关键词： rotor bearing system local defect super-harmonic resonance HB-AFT method

Multiscale Theories and Applications:From Microstructure Design to Macroscopic Assessment for Carbon Nanotubes Networks

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 18-35页

作者： Jiachao Ji yulin jin Anping Hua Chunhua Zhu Junhua Zhao Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan UniversityWuxi 214122China Institute of Mechanics and Advanced Materials School of Mechanical EngineeringJiangnan UniversityWuxi 214122China

Carbon nanotube(CNT)networks enable CNTs to be used as building blocks for synthesizing novel advanced materials,thus taking full advantage of the superior properties of individual *** analyses have to be adopted to study the load transfer mechanisms of CNT networks from the atomic scale to the macroscopic scale due to the huge computational *** them,fully resolved structural features include the graphitic honeycomb lattice(atomic),inter-tube stacking(nano)and assembly(meso)of *** an atomic scale,the elastic properties,ultimate stresses,and failure strains of individual CNTs with distinct chiralities and radii are obtained under various loading conditions by molecular *** dependence of the cohesive energies on spacing distances,crossing angles,size and edge effects between two CNTs is analyzed through continuum modeling in *** mesoscale models,which neglect the atomic structures of individual CNTs but retain geometrical information about the shape of CNTs and their assembly into a network,have been developed to study the multi-level mechanism of material deformation and microstructural evolution in CNT networks under stretching,from elastic elongation,strengthening to damage and *** paper summarizes the multiscale theories mentioned above,which should provide insight into the optimal assembling of CNT network materials for elevated mechanical performance.

关键词： Carbon nanotube networks Hierarchical structures Multiscale theories Mesoscale model

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全民健身数字化转型的践行路径分析

当代体育科技 2024年第11期14卷 94-96,134页

作者：金誉琳翟永华天津师范大学体育科学学院天津300000

“十四五”时期是我国开启全面建设社会主义现代化国家新征程的第一个五年,也是实现体育现代化远景目标的开局之际。在此背景下,全民健身数字化转型应时而生,且正在成为我国体育事业高质量发展的重要引擎。该文采用文献资料法、逻辑分析... 详细信息

“十四五”时期是我国开启全面建设社会主义现代化国家新征程的第一个五年,也是实现体育现代化远景目标的开局之际。在此背景下,全民健身数字化转型应时而生,且正在成为我国体育事业高质量发展的重要引擎。该文采用文献资料法、逻辑分析法,结合全民健身发展的现实需要与时代际遇,提出紧密多元主体联动协作、牢固数字基础设施建设、打造精准化数据平台、推动城乡一体共建共享、加大虚拟现实技术应用的数字化转型路径,为推动全民健身朝向数字化转型提供借鉴价值。

关键词：全民健身数字化转型现代科技践行路径

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A new nonlinear force model to replace the Hertzian contact model in a rigid-rotor ball bearing system

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Applied Mathematics and Mechanics(English Edition) 2018年第3期39卷 365-378页

作者： yulin jin Zhenyong LU Rui YANG Lei HOU Yushu CHEN School of Astronautics Harbin Institute of Technology School of Energy Science and Engineering Harbin Institute of Technology

A new nonlinear force model based on experimental data is proposed to replace the classical Hertzian contact model to solve the fractional index nonlinearity in a ball bearing system. Firstly, the radial force and the radial deformation are measured by statics experiments, and the data are fitted respectively by using the Hertzian contact model and the cubic polynomial model. Then~ the two models are compared with the approximation formula appearing in Aeroengine Design Manual. In consequence, the two models are equivalent in an allowable deformation range. After that, the relationship of contact force and contact deformation for single rolling element between the races is cal- culated based on statics equilibrium to obtain the two kinds of nonlinear dynamic models in a rigid-rotor ball bearing system. Finally~ the displacement response and frequency spectrum for the two system models are compared quantitatively at different rotational speeds, and then the structures of frequency-amplitude curves over a wide speed range are compared qualitatively under different levels of radial clearance, amplitude of excitation, and mass of supporting rotor. The results demonstrate that the cubic polynomial model can take place of the Hertzian contact model in a range of deformation.

关键词： rolling element bearing, Hertzian contact, fractional index cubic polyno-miali rotor ball bearing system

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儿童气管切开套管周围结石1例

中华耳鼻咽喉头颈外科杂志 2024年第2期59卷 171-173页

作者：黄宇童陈彦球秦昊温慧刘文龙刘月红梁瑞金宇林广州医科大学附属妇女儿童医疗中心耳鼻咽喉头颈外科、广东省儿童健康与疾病临床医学研究中心广州510623 广州医科大学附属妇女儿童医疗中心柳州医院耳鼻咽喉头颈外科柳州545000 广州医科大学附属妇女儿童医疗中心麻醉科广州510623

本文报道1例气管切开术后5年的9岁患儿,因“呼吸不畅6个月余,需行手术更换气管切开套管”入院。术前胸片见金属气切套管下段高密度影,术中发现气管切开套管周围被结石包绕,清理结石并更换套管后发现部分结石碎块脱入气道,在纤维支气管... 详细信息

本文报道1例气管切开术后5年的9岁患儿,因“呼吸不畅6个月余,需行手术更换气管切开套管”入院。术前胸片见金属气切套管下段高密度影,术中发现气管切开套管周围被结石包绕,清理结石并更换套管后发现部分结石碎块脱入气道,在纤维支气管镜引导下取出碎块。术后患儿通气明显改善,术后3 d出院,预后良好。

关键词：气管切开套管气管切开术后预后良好术前胸片结石术中发现气切套管呼吸不畅

The Applications of Order Reduction Methods in Nonlinear Dynamic Systems

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Sound & Vibration 2020年第2期54卷 113-125页

作者： Nan Wu Kuan Lu yulin jin Haopeng Zhang Yushu Chen Institute of Vibration Engineering Northwestern Polytechnical UniversityXi’an710072China School of Astronautics Harbin Institute of TechnologyHarbin150001China School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Two different order reduction methods of the deterministic and stochastic systems are discussed in this ***,the transient proper orthogonal decomposition(T-POD)method is introduced based on the high-dimensional nonlinear dynamic *** optimal order reduction conditions of the T-POD method are provided by analyzing the rotor-bearing system with pedestal looseness fault at both *** efficiency of the T-POD method is verified via comparing with the results of the original ***,the polynomial dimensional decomposition(PDD)method is applied to the 2 DOFs spring system considering the uncertain stiffness to study the amplitude-frequency *** numerical results obtained by the PDD method agree well with the Monte Carlo simulation(MCS)*** results of the PDD method can approximate to MCS better with the increasing of the polynomial ***,the Uniform-Legendre polynomials can eliminate perturbation of the PDD method to a certain extent via comparing it with the Gaussian-Hermite polynomials.

关键词： Uncertainty T-POD method PDD method rotor spring

罗哌卡因通过JAK-PI3K-AKT通路抑制宫颈癌细胞增殖的研究

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今日药学 2024年第1期34卷 18-22页

作者：陈月月郭小花刘文兴金宇林陈茜广州医科大学附属妇女儿童医疗中心麻醉科广东省儿童健康与疾病临床医学研究中心广东广州510623

目的探讨罗哌卡因对宫颈癌细胞的影响,为宫颈癌手术麻醉剂的选择提供实验依据。方法以不同浓度罗哌卡因作用于宫颈癌细胞Hela,应用MTT法检测细胞增殖能力,流式细胞术检测细胞凋亡情况,Transwell小室法测定细胞侵袭力变化。建立人宫颈... 详细信息

目的探讨罗哌卡因对宫颈癌细胞的影响,为宫颈癌手术麻醉剂的选择提供实验依据。方法以不同浓度罗哌卡因作用于宫颈癌细胞Hela,应用MTT法检测细胞增殖能力,流式细胞术检测细胞凋亡情况,Transwell小室法测定细胞侵袭力变化。建立人宫颈癌Hela细胞裸鼠异种移植模型,观察罗哌卡因处理对肿瘤细胞生长的影响。Western-blot蛋白印迹法检测STAT3磷酸化水平和JAK、PI3K、AKT蛋白表达水平,抑制剂及罗哌卡因处理后STAT3磷酸化水平。结果罗哌卡因可显著抑制宫颈癌细胞Hela的生长及迁徙能力,促进其凋亡,抑制STAT3磷酸化及JAK-PI3K-AKT通路;动物实验结果显示,罗哌卡因可抑制宫颈癌细胞生长。结论罗哌卡因可通过抑制JAK-PI3K-AKT通路对宫颈癌细胞产生抑制作用。

关键词：罗哌卡因宫颈癌凋亡 AKT信号通路麻醉

Puerarin mediated miR-30b-5p targeting fibroblast activation protein against oral submucous fibrosis

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BIOCELL 2024年第4期48卷 591-599页

作者： SAIFEI XIE HUI XIE jinCAI GUO jin TAN yulin YU MINYI ZHANG SHANG WEN Department of Periodontal Mucosa Hunan University of Chinese MedicineChangshaChina Department of Periodontal Mucosa Changsha Stomatology HospitalChangshaChina Department of Pharmacy Changsha Stomatology HospitalChangshaChina Department of Stomatology The First Hospital of Hunan University of Chinese MedicineChangshaChina

Background:Puerarin(Pue)has been reported to be a natural active ingredient with multiple antiﬁbrotic *** work aimed at exploring the function of Pue in oral submucousﬁbrosis(OSF)***:Human oral mucosaﬁbroblasts(hOMF)were induced with transforming growth factor beta1(TGF-β1)and intervened with *** ofﬁbrosis-related markers were analyzed by Western blot and IF *** viability was characterized by the CCK-8 *** of miR-30 family members were quantiﬁed by *** correlation betweenﬁbroblast activation protein(FAP)and miR-30 family expression was evaluated by the Pearson correlation coefﬁ*** prediction and dual-luciferase reporter assay were employed to verify the regulation between FAP and *** speciﬁc mechanism of Pue on OSF was explored through the promotion or inhibition of ***:After induction by TGF-β1,hOMF showed upregulated Collagen I,Collagen III,and FAP expressions,while miR-30 family expression was downregulated with miR-30b-5p being the most signiﬁ*** intervention inhibited the excessive proliferation of TGF-β1-induced hOMF,downregulated FAP,collagen type 3(COL3A1),collagen type 1(COL1A1),matrix metalloproteinase 1(MMP1),and matrix metalloproteinase 3(MMP3)expressions,and restored miR-30 family *** prediction and dual-luciferase reporter assay revealed that miR-30b-5p selectively inhibited FAP ***,miR-30b-5p mimic suppressed the excessive proliferation of TGF-β1-induced hOMF and declinedﬁbrosis *** intervention signiﬁcantly reversed the promotion of TGF-β1-induced OSF by miR-30b-5p ***:Pue mediated miR-30b-5p targeting FAP against OSF,which provided a theoretical basis for the pathogenesis research and Pue application in OSF.

关键词： Puerarin miR-30b-5p FAP Oral submucous fibrosis

Comparison of Ex‑PRESS implantation versus trabeculectomy combined with phacoemulsification in primary open‑angle glaucoma:a retrospective in vivo confocal microscopy study

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Eye and Vision 2024年第2期10卷 1-11页

作者： Yuqiao Zhang Beiting He yulin Zhang jin Zeng Yanlei Chen Yongyi Niu Honghua Yu Yongjie Qin Hongyang Zhang Department of Ophthalmology Guangdong Eye InstituteGuangdong Academy of Medical SciencesGuangdong Provincial People’s HospitalNo.106 Zhongshan Er RoadGuangzhou 510080China Shantou University Medical College ShantouChina The Second School of Clinical Medicine Southern Medical UniversityGuangzhouChina Department of Ophthalmology School of MedicineSouth China University of TechnologyGuangzhouChina

Background:To compare the efficacy of Ex-PRESS implantation versus trabeculectomy combined with ***:A retrospective 12-month study on patients with coincident primary open-angle glaucoma(POAG)and *** patients underwent combined phacoemulsification and Ex-PRESS implant(Phaco-ExPRESS,n=35)or phacotrabeculectomy(Phaco-Trab,n=35).The morphological structures of the filtering bleb were examined by slitlamp,anterior segment optical coherence tomography(AS-OCT)and in vivo confocal microscopy(IVCM).Complete success was defined as postoperative intraocular pressure(IOP)<18 mmHg without the use of anti-glaucoma *** success was defined as postoperative IOP<18 mmHg with or without anti-glaucoma *** data were collected preoperatively and postoperatively at 2 weeks,1 month,3 months,6 months,and 12 ***:No significant difference in the variables such as age,IOP and perimetry was found between the groups of Phaco-ExPRESS and *** the one-year postoperative visit for filtering blebs,Phaco-ExPRESS increased the mean area of epithelial microcysts significantly from 0.10±0.05 to 0.20±0.09μm^(2)perμm^(2),while Phaco-Trab decreased the mean area significantly from 0.08±0.04 to 0.04±0.06μm^(2)perμm^(2).Notably,the hyperreflective dots detected by IVCM decreased by 84.9%in Phaco-ExPRESS but increased by 36.3%in *** hyperreflective dots were further identified as neutrophil-and monocyte-like *** number of these cells were negatively correlated with the microcysts area(r=−0.7,P<0.01)but positively associated with the grade of connective tissue(r=0.5,P<0.01).By creating different microstructural changes in the filtering blebs,Phaco-ExPRESS produced a higher complete success rate(84.9%vs.41.2%,P<0.01)and significant decrease in the number of anti-glaucoma medications(P<0.01)when compared with those in ***,the qualified success showed no significant difference between the two groups(

关键词： POAG Ex-PRESS Phacoemulsification Confocal microscopy

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民航客机油箱建模与油量传感器姿态误差修正

北京航空航天大学学报 2005年第2期31卷 218-222页

作者：金宇林庄达民杨钦北京航空航天大学计算机学院北京100083 北京航空航天大学航空科学与工程学院北京100083

实现民航客机的飞机油箱建模 ,提出对油箱的油量传感器示数的姿态误差进行修正的算法 .建模过程基于二维限定Delaunay三角剖分和插值 ,生成油箱的表面 .利用油量传感器错误示数和当前飞行姿态角 ,利用油箱表面三角网格 ,将油箱内含油体... 详细信息

实现民航客机的飞机油箱建模 ,提出对油箱的油量传感器示数的姿态误差进行修正的算法 .建模过程基于二维限定Delaunay三角剖分和插值 ,生成油箱的表面 .利用油量传感器错误示数和当前飞行姿态角 ,利用油箱表面三角网格 ,将油箱内含油体积进行三维三棱柱剖分和三维四面体剖分 .计算四面体体积之和求得油箱正确的含油量 .与当前正在使用的切片算法在效率和使用范围方面进行深入比较与分析 .实现民航客机油箱三维建模 ,并且利用已建立的模型修正其油量传感器示数姿态误差 .算法优于切片算法 .

关键词：民航油箱油量传感器姿态误差三角网格