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Progressive Failure Analysis of Composite/Aluminum Riveted Joints Subjected to Pull-Through Loading

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 129-138页

作者： yuxing yang Yongjie Bao Xueshu Liu Jinlong Wang Fengming Du Marine Engineering College Dalian Maritime UniversityDalian116026China School of Automotive Engineering Dalian University of TechnologyDalian116024China

Out-of-plane mechanical properties of the riveted joints restrict the performance of the wing box assembly of airplane.It is necessary to investigate the pull-through performance of the composite/metal riveted joints in order to guide the riveting design and ensure the safety of the wing box assembly.The progressive failure mechanism of composite/aluminum riveted joint subjected to pull-through loading was investigated by experiments and finite element method.A progressive damage model based on the Hashin-type criteria and zero-thickness cohesive zone method was developed by VUMAT subroutine,which was validated by both open-hole tensile test and three-point bending test.Predicted load-displacement response,failure modes and damage propagation were analysed and compared with the results of the pull-through tests.There are 4 obvious characteristic stages on the load-displacement curve of the pull-through test and that of the finite element model:first load take-up stage,damage stage,second load take-up stage and failure stage.Relative error of stiffness,first load peak and second load peak between finite element method and experiments were 8.1%,-3.3%and 10.6%,respectively.It was found that the specimen was mainly broken by rivet-penetration fracture and delamination of plies of the composite laminate.And the material within the scope of the rivet head is more dangerous with more serious tensile damages than other regions,especially for 90°plies.This study proposes a numerical method for damage prediction and reveals the progressive failure mechanism of the hybrid material riveted joints subjected to the pull-through loading.

关键词： Composite/metal joints Riveted joints Pull-through test Progressive damage model

ARCosmetics:a real-time augmented reality cosmetics try-on system

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Frontiers of Computer Science 2023年第4期17卷 15-28页

作者： Shan AN Jianye CHEN Zhaoqi ZHU Fangru ZHOU yuxing yang Yuqing MA Xianglong LIU Haogang ZHU Tech.&Data Center *** Inc.Beijing 100176China State Key Lab of Software Development Environment Beihang UniversityBeijing 100191China

A virtual cosmetics try-on system provides a realistic try-on experience for consumers and helps them efficiently choose suitable cosmetics.In this article,we propose a real-time augmented reality virtual cosmetics try-on system for smartphones(ARCosmetics),taking speed,accuracy,and stability into consideration at each step to ensure a better user experience.A novel and very fast face tracking method utilizes the face detection box and the average position of facial landmarks to estimate the faces in continuous frames.A dynamic weight Wing loss is introduced to assign a dynamic weight to every landmark by the estimated error during training.It balances the attention between small,medium,and large range error and thus increases the accuracy and robustness.We also designed a weighted average method to utilize the information of the adjacent frame for landmark refinement,guaranteeing the stability of the generated landmarks.Extensive experiments conducted on a large 106-point facial landmark dataset and the 300-VW dataset demonstrate the superior performance of the proposed method compared to other state-of-the-art methods.We also conducted user satisfaction studies further to verify the efficiency and effectiveness of our ARCosmetics system.

关键词： facial landmark localization face tracking stabilization augmented reality virtual try-on

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固体探空火箭迭代制导方法研究

固体火箭技术 2024年第1期47卷 135-142页

作者：唐冰涛陈华兵杨宇星江小娟西安航天动力技术研究所西安710025 西北工业集团有限公司西安710043

固体探空火箭在实施某类载荷远程投递任务时,要求接近落点的精度在千米级,由于火箭一般在大气层内的主动段实施有效的制导控制,其制导时间短,气动影响无法忽视,实现落点精度控制难度很大。针对该问题提出了一种适用于固体探空火箭在大... 详细信息

固体探空火箭在实施某类载荷远程投递任务时,要求接近落点的精度在千米级,由于火箭一般在大气层内的主动段实施有效的制导控制,其制导时间短,气动影响无法忽视,实现落点精度控制难度很大。针对该问题提出了一种适用于固体探空火箭在大气层内的迭代制导方法,通过在线计算剩余视速度和视位置增量,对固体探空火箭落点进行迭代计算,形成制导控制指令。仅在主动段进行制导控制,对再入段进行气动补偿,使得固体火箭落点控制达到了较高的精度。数值仿真分析表明:该方法落点精度较传统的摄动制导方法提高了1个数量级,体现出该迭代制导方法的优越性。

关键词：气动阻力视速度视位置气动补偿迭代制导摄动制导

High-efficiency and broadband four-wave mixing in a silicon-graphene strip waveguide with a windowed silica top layer

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Photonics Research 2018年第10期6卷 965-970页

作者： yuxing yang ZHENZHEN XU XINHONG JIANG YU HE XUHAN GUO YONG ZHANG CIYUAN QIU YIKAI SU State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong University

We experimentally demonstrate high-efficiency and broadband four-wave mixing in a silicon-graphene strip waveguide. A four-wave mixing conversion efficiency of -38.7 d B and a 3-dB conversion bandwidth of 35 nm are achieved in the silicon-graphene strip waveguide with an optimized light-graphene interaction length of 60 μm. The interaction length is controlled by a windowed area of silica layer on the silicon waveguide.Numerical simulations and experimental studies are carried out and show a nonlinear parameter γGOSas large as 10~4 W^(-1)· m^(-1).

关键词：石墨烯频率通讯技术发展现状

梁式与推出加载对钢-混凝土结构栓钉承载力影响机理分析

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混凝土 2024年第1期 64-68页

作者：刘冰洁范亮石璐杨玉星重庆交通大学土木工程学院重庆400074 武汉工程科技学院湖北武汉430200

针对钢-混凝土结构中栓钉在推出和梁式加载时不同的受力行为,通过开展数值分析及试验验证,研究了两种加载情况下的栓钉承载力、刚度及传力路径等典型受力性能差异,提出了预留孔尺寸效应、钉簇间受力非线性梯度效应及单簇钉群受力簇群效... 详细信息

针对钢-混凝土结构中栓钉在推出和梁式加载时不同的受力行为,通过开展数值分析及试验验证,研究了两种加载情况下的栓钉承载力、刚度及传力路径等典型受力性能差异,提出了预留孔尺寸效应、钉簇间受力非线性梯度效应及单簇钉群受力簇群效应等影响效应及机理,建立了梁式加载单钉抗剪承载力计算式。研究表明:梁式加载时栓钉抗剪承载力低于推出加载,抗剪刚度高于推出加载;梁式加载极限承载力时栓钉根部受力相较推出加载呈现更为显著的非线性关系;尺寸效应使组合梁中栓钉承载力略高于推出试件;组合梁中簇群效应更为显著,使单钉承载力降低。梯度效应使组合梁栓钉根部受力非线性更为明显。基于上述分析,提出了考虑3种效应的梁式加载单钉抗剪承载力计算式。

关键词：钢-混组合结构推出加载梁式加载抗剪承载力

军事训练中膝关节交叉韧带损伤的调查分析及预防策略

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海军医学杂志 2024年第3期45卷 226-230页

作者：张蕊杨玉兴李俊中国人民解放军联勤保障部队第九四〇医院中医康复科甘肃兰州730050

目的调查分析军事训练导致膝关节交叉韧带损伤状况,制定相应的预防措施。方法回顾性分析2021年1月至2022年1月中国人民解放军联勤保障部队第九四〇医院中医康复科收治的150例军事训练引起膝关节交叉韧带损伤患者的临床资料,对前后交叉... 详细信息

目的调查分析军事训练导致膝关节交叉韧带损伤状况,制定相应的预防措施。方法回顾性分析2021年1月至2022年1月中国人民解放军联勤保障部队第九四〇医院中医康复科收治的150例军事训练引起膝关节交叉韧带损伤患者的临床资料,对前后交叉韧带损伤的构成比、左右膝交叉韧带损伤的构成比、交叉韧带损伤合并的其他部位损伤、常见引起交叉韧带损伤的军事训练项目进行分析。结果前交叉韧带损伤145例(96.67%),后交叉韧带损伤2例(1.33%),前后交叉韧带同时损伤3例(2.00%);前交叉韧带损伤构成比高于后交叉韧带损伤。左膝关节和右膝关节交叉韧带损伤各75例(50.00%)。交叉韧带损伤伴随半月板损伤96例(64.00%)、伴随侧副韧带损伤32例(21.33%)、伴随骨损伤19例(12.67%),前交叉韧带损伤无其他伴随损伤患者仅3例(2.00%);交叉韧带损伤合并半月板损伤的构成比高于合并侧副韧带损伤、合并骨损伤、无其他合并损伤的构成比。3 km和5 km长跑、木马训练、400 m障碍是引起交叉韧带损伤的军事训练的前3个项目。结论膝关节交叉韧带损伤导致军事训练官兵伤残,影响我军战斗力及官兵生活质量,应加强安全警示和掌握正确的训练方法以有效减少交叉韧带损伤的发生。

关键词：军事训练交叉韧带损伤流行病学预防措施

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《家山》折射的生命观念浅探

文化创新比较研究 2024年第10期8卷 1-5页

作者：杨宇星刘婉婷彭玲湖南人文科技学院文学院湖南娄底417000

后疫情时代,面临人口出生率低、社会焦虑、全球生态危机等问题,一些人的生命责任感、生活幸福感不高,对生命意义的追求也更加迷惘。《家山》通过描写具有地方特色的婚葬习俗、山水秀丽的自然景观、丰富多彩的人物形象,展现沙湾村人尊生... 详细信息

后疫情时代,面临人口出生率低、社会焦虑、全球生态危机等问题,一些人的生命责任感、生活幸福感不高,对生命意义的追求也更加迷惘。《家山》通过描写具有地方特色的婚葬习俗、山水秀丽的自然景观、丰富多彩的人物形象,展现沙湾村人尊生重死的婚丧礼仪、家国天下的生命价值、平等和谐的生命智慧,这是沙湾村独特的生命观念,也是湖湘民俗视景中一种独特的生命现象。这种对生命的独特见解与践行对树立积极的主体精神具有重要意义,独特的生命观念与现实的生命困境结合为现代人的生存提供精神力量,为中国特色社会主义道路建设贡献发展方案。

关键词：《家山》生命观念价值取向尊生重死家国天下平等和谐

Voltage rise rate-related generalised probabilistic lifetime model of turn-to-turn insulation in inverter-fed motors

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High Voltage 2024年第1期9卷 46-55页

作者： Yan yang Xueyang Bai yuxing Lei Kai Liu Guangning Wu School of Electrical Engineering Southwest Jiaotong UniversityChengduChina

The lifetime model of turn-to-turn insulation in inverter-fed motors is studied.A lifetime model has been built by considering the effect of inverter-generated high voltage rise rate(dv/dt up to 20 V/ns).This model is followed by the generalised probabilistic model,in which the lifetime is proportional to the nth power of the voltage rise rate.Moreover,by investigating the effect of voltage rise rate on the partial discharge characteristics,it is found that the effect of voltage rise rate on the charge transport process in a voltage cycle is similar to that of the voltage amplitude.The enhanced partial discharge activity and induced charges are responsible for accelerated ageing and thus determine the final lifetime of turn-to-turn insulation.In this case,the generalised probabilistic electric lifetime model is applicable to the voltage rise rate as well as the voltage amplitude.

关键词： lifetime inverter insulation

荆僵白果膏联合奥马珠单抗治疗老年支气管哮喘患者的效果及其对气道重塑和气道炎症的影响

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实用心脑肺血管病杂志 2024年第7期32卷 101-105页

作者：周进王文杰丁静张艳红杨宇星北京中医药大学东方医院秦皇岛医院肺病科河北省秦皇岛市066000 北京中医药大学东方医院秦皇岛医院重症医学科河北省秦皇岛市066000

目的分析荆僵白果膏联合奥马珠单抗治疗老年支气管哮喘患者的效果及其对气道重塑和气道炎症的影响。方法选取2021年1月—2023年9月北京中医药大学东方医院秦皇岛医院收治的老年支气管哮喘患者120例为研究对象。采用简单随机抽样法将患... 详细信息

目的分析荆僵白果膏联合奥马珠单抗治疗老年支气管哮喘患者的效果及其对气道重塑和气道炎症的影响。方法选取2021年1月—2023年9月北京中医药大学东方医院秦皇岛医院收治的老年支气管哮喘患者120例为研究对象。采用简单随机抽样法将患者分为对照组、奥马珠单抗组、荆僵白果膏组、联合组,各30例。对照组接受布地奈德福莫特罗粉吸入剂治疗,奥马珠单抗组在对照组的基础上皮下注射奥马珠单抗,荆僵白果膏组在对照组的基础上接受荆僵白果膏治疗,联合组在对照组的基础上接受荆僵白果膏联合奥马珠单抗治疗,四组治疗疗程均为12周。比较四组临床疗效及治疗前、治疗后气道重塑指标〔血管内皮生长因子(VEGF)、单核细胞趋化蛋白1(MCP-1)、支气管管腔面积(LA)〕、气道炎症指标〔核因子κB(NF-κB)、IL-8、IL-6、IgE、嗜酸粒细胞计数(EOS)〕。结果联合组临床疗效优于对照组、奥马珠单抗组、荆僵白果膏组(P<0.05)。治疗后,奥马珠单抗组、荆僵白果膏组、联合组VEGF、MCP-1低于对照组,支气管LA大于对照组(P<0.05);治疗后,联合组VEGF、MCP-1低于奥马珠单抗组、荆僵白果膏组,支气管LA大于奥马珠单抗组、荆僵白果膏组(P<0.05)。对照组、奥马珠单抗组、荆僵白果膏组、联合组治疗后VEGF、MCP-1分别低于本组治疗前,治疗后支气管LA分别大于本组治疗前(P<0.05)。治疗后,奥马珠单抗组、荆僵白果膏组、联合组NF-κB、IL-8、IL-6、IgE、EOS低于对照组(P<0.05);治疗后,荆僵白果膏组IL-6低于奥马珠单抗组(P<0.05);治疗后,联合组NF-κB、IL-8、IL-6、IgE、EOS低于奥马珠单抗组、荆僵白果膏组(P<0.05)。对照组、奥马珠单抗组、荆僵白果膏组、联合组治疗后NF-κB、IL-8、IL-6、IgE、EOS分别低于本组治疗前(P<0.05)。结论荆僵白果膏联合奥马珠单抗可有效提高老年支气管哮喘患者的临床疗效,抑制气道重塑,减轻气道炎症。

关键词：哮喘老年人荆僵白果膏奥马珠单抗治疗结果气道重塑气道炎症