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Friction 2024年第1期12卷 74-94页

作者： jiabao yin Chun LU Jiliang MO School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province Chengdu 610031China

A comprehensive modeling strategy for studying the thermomechanical tribological behaviors is proposed in this *** wear degradation considering the influence of temperature(T)is predicted by Archard wear model with the help of the UMESHMOTION subroutine and arbitrary Lagrangian–Eulerian(ALE)remeshing *** the proposed method,the thermomechanical tribological behaviors of railway vehicle disc brake system composed of forged steel brake disc and Cu-based powder metallurgy(PM)friction block are studied *** effectiveness of the proposed methodology is validated by experimental test on a self-designed scaled brake test bench from the perspectives of interface temperature,wear degradation,friction noise and vibration,and contact status *** work can provide an effective way for the investigation of thermomechanical tribological behaviors in the engineering field.

关键词： tribological behaviors thermomechanical field wear prediction finite element simulation disc brake system railway vehicle

Scuffing failure analysis based on a multiphysics coupling model and experimental verification

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Friction 2024年第6期12卷 1214-1234页

作者： Bugao LYU Xianghui MENG jiabao yin Yi CUI Chengen WANG School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

General reductions in lubricant viscosities and increasing loads in machine components highlight the role of tribofilms in providing surface protection against ***,the relationship between the scuffing process and the growth and removal of tribofilm is not well *** this study,a multiphysics coupling model,which includes hydrodynamic lubrication,asperity contact,thermal effect,tribochemistry reaction,friction,and surface wear,was developed to capture the initiation of surface *** and experiments for a piston ring and cylinder liner contact were conducted following a step-load sequence under different temperature *** results show that high temperature and extreme load could induce the lubricant film collapse,which in turn triggers the breakdown of the tribofilm due to the significantly increased removal *** failures of both lubricant film and tribofilm progress instantaneously in a coupling way,which finally leads to severe scuffing.

关键词： scuffing failure tribofilm boundary lubrication multiphysics coupling effects

屏幕暴露与学龄前孤独症谱系障碍儿童情绪行为问题相关性研究

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中国全科医学 2024年第25期27卷 3136-3142,3158页

作者：段桂琴葛林铃尹嘉宝赵明方聂文毫郑州大学第三附属医院儿童发育行为科河南郑州市450052

背景既往已有多项研究证实屏幕暴露现象在学龄前儿童中普遍存在,并且与儿童情绪行为问题相关,现有研究多集中在正常学龄前儿童,有关屏幕暴露与学龄前孤独症谱系障碍(ASD)儿童情绪行为问题相关的研究较为罕见。目的调查学龄前ASD儿童屏... 详细信息

背景既往已有多项研究证实屏幕暴露现象在学龄前儿童中普遍存在,并且与儿童情绪行为问题相关,现有研究多集中在正常学龄前儿童,有关屏幕暴露与学龄前孤独症谱系障碍(ASD)儿童情绪行为问题相关的研究较为罕见。目的调查学龄前ASD儿童屏幕暴露情况及情绪行为问题异常检出情况,探究屏幕暴露与学龄前ASD儿童情绪行为问题有无相关。方法选择2022年2—8月在郑州大学第三附属医院儿童发育行为科就诊的符合《精神障碍诊断和统计手册》(DSM-V)孤独症诊断标准的ASD学龄前儿童为ASD组,同期选取郑州市某幼儿园正常发育儿童为对照组。由两组儿童主要照护人进行填写屏幕暴露问卷及长处与困难问卷(家长版)。结果两组儿童屏幕接触时间、家长对屏幕管理、“屏幕剥夺”反应比较,差异无统计学意义(P<0.001);ASD组儿童亲社会行为、困难总分及各个分维度(情绪症状、品行问题、多动/注意缺陷问题、同伴交往问题)异常检出率均高于对照组(P<0.001);Logistic回归分析发现电子设备放置在睡觉或玩耍空间、观看时照护人是否互动讲解、照护人对孩子观看电子屏幕态度、接触电子屏幕是主动要求还是被动参与、强制关掉电子屏幕孩子反应是学龄前ASD儿童情绪行为问题的影响因素(P<0.05)。结论屏幕暴露可能对ASD儿童情绪行为问题产生影响,家长应合理管理学龄前ASD儿童屏幕使用。

关键词：孤独症屏幕暴露情绪行为问题学龄前儿童影响因素

无创左心室压力-应变环技术评估甲亢患者的左心室收缩功能

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医学影像学杂志 2024年第4期34卷 16-20页

作者：王末凤甘玲张加琪尹家保锦州医科大学湖北医药学院附属襄阳市第一人民医院研究生联合培养基地超声影像科湖北襄阳441000 湖北医药学院附属襄阳市第一人民医院超声影像科湖北襄阳441000

目的探讨应用无创左心室压力-应变环(LV-PSL)技术评估甲状腺功能亢进症(甲亢)患者的左心室收缩功能的价值。方法选取91例甲亢患者,根据是否接受过治疗分为初诊组(49例)及治疗组(42例),并纳入健康志愿者(40例)作为对照组。应用常规超... 详细信息

目的探讨应用无创左心室压力-应变环(LV-PSL)技术评估甲状腺功能亢进症(甲亢)患者的左心室收缩功能的价值。方法选取91例甲亢患者,根据是否接受过治疗分为初诊组(49例)及治疗组(42例),并纳入健康志愿者(40例)作为对照组。应用常规超声心动图获取相关参数,斑点追踪技术获取整体纵向应变(GLS),无创LV-PSL技术获取整体做功指数(GWI)、整体有用功(GCW)、整体无用功(GWW)、整体做功效率(GWE),比较上述三组参数的差异。分析收缩压(SBP)、心率(HR)与GLS、GWI、GCW、GWW、GWE的相关性。结果与对照组比较,初诊组和治疗组HR、主动脉舒张末期(AOEDD)、GWW均增高,而GLS、GWI、GWE均降低;且初诊组SBP增高,而GCW降低,差异具有统计学意义(P<0.05)。与初诊组比较,治疗组SBP、HR、GWW降低,而GWE增高,差异具有统计学意义(P<0.05)。相关性分析显示SBP与GWW呈正相关(r=0.277,P<0.01);与GLS、GWE呈负相关(r=-0.271、-0.259,P<0.01);HR与GLS、GWE呈负相关(r=-0.220、-0.185,P<0.05),与GWI、GCW也呈负相关(r=-0.447、-0.353, P<0.01)。结论无创LV-PSL技术可早期定量评估甲亢患者左心室收缩功能,为临床早期预测、早期干预及治疗效果评估提供参考价值,治疗后甲亢患者左心室收缩功能可恢复。

关键词：甲状腺功能亢进症压力-应变环左心室超声检查

氢质子磁共振波谱分析在女性膀胱过度活动症诊断中的应用价值

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临床泌尿外科杂志 2024年第2期39卷 107-110页

作者：尹加宝席俊华崔萍魏灿吴畏张艳斌合肥市第二人民医院泌尿外科合肥230011 皖南医学院合肥市第二人民医院医学影像中心

目的:探讨利用氢质子磁共振波谱(hydrogen proton magnetic resonance spectroscopy,^(1)H-MRS)分析技术检测女性膀胱过度活动症(overactive bladder,OAB)患者与对照组之间膀胱壁胆碱(choline,Cho)水平的差异并探讨其潜在诊断价值。方法:选择2022年7月—2023年8月于合肥市第二人民医院诊断为OAB的女性患者(OAB组)和同时期与患者年龄、体重指数(BMI)相匹配的女性健康志愿者(对照组)。所有受试者均进行了2次膀胱多体素^(1)H-MRS扫描,分别为初始尿意产生时(膀胱充盈期)及排空膀胱后(膀胱空虚期)。通过Siemens Skyra3.0T磁共振成像系统自带后处理软件计算出膀胱前壁、后壁、两侧壁Cho/肌酸(creatine,Cr)比值,并采用t检验进行组间和组内比较。结果:本研究OAB组纳入23例,对照组纳入17例。2组进行组间比较,OAB组膀胱充盈期Cho含量较对照组显著升高(t=-19.585,P<0.01),OAB组膀胱空虚期Cho含量较对照组升高(t=-2.243,P=0.033);2组分别行组内比较,OAB组膀胱充盈期Cho含量显著高于膀胱空虚期(t=-17.989,P<0.01),对照组膀胱充盈期与膀胱空虚期Cho含量差异无统计学意义(t=-1.254,P=0.220)。2组年龄(P=0.577)、BMI(P=0.698)等指标比较差异无统计学意义。结论:^(1)H-MRS分析技术在女性OAB的诊断中可能具有较好的潜在价值。

关键词：膀胱过度活动症胆碱化合物氢质子磁共振波谱

Enhanced energy density and fast-charging ability via directional particle configuration

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Journal of Energy Chemistry 2024年第3期90卷 152-164,I0005页

作者： Xiongwei Wu Shanguang lv jiabao Li Xingrong yin Xuewen Wu Jun Liu Jie Zhang Yuhan Yu Bei Long Hunan yinfeng New Energy Co.Ltd. Changsha 410019HunanChina

The limited energy density of lithium-ion capacitors poses a significant obstacle to their widespread application,primarily stemming from the inability of the electrodes to simultaneously fulfill both high energy density and rapid charging *** data demonstrate that a directional particle configuration can enhance charging speed while maintaining high-capacity density,but it is rarely ***,we have developed a particle-level electrochemical model capable of reconstructing an electrode with a directional particle *** employing this method,an investigation was conducted to explore how the spatial morphology characteristics of particle configuration impact the energy storage characteristics of *** demonstrate that rational particle configuration can effectively enhance the transport of lithium ions and create additional space for lithium-ion *** the same particle size distribution,the best electrode can increase the discharge capacity by up to132.4% and increase the charging SOC by 11.3% compared to the ordinary electrode under the condition of 6 *** findings provide a further understanding of the energy storage mechanism inside the anisotropic particle distribution electrode,which is important for developing high-performance lithium-ion capacitors.

关键词： Supercapacitor Gradient design strategies Energy storage Charge transport

A digital twins enabled underwater intelligent internet vehicle path planning system via reinforcement learning and edge computing

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Digital Communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen Yang Meng Xi jiabao Wen Yang Li Houbing Herbert Song School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked Globe Laboratory(SONG Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater Glider(AUG)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： Digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

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Defence Technology（防务技术） 2024年第2期32卷 309-316页

作者： Jie Ren Yunfeng Li Mingyu Li Xingyu Wu jiabao Wang Qingxuan Zeng State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

VxWorks5.5下电子盘DMA驱动程序设计与实现

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电子技术应用 2016年第11期42卷 40-43页

作者：尹加豹江苏自动化研究所江苏连云港222061

在嵌入式实时操作系统中,经常需要实时读写硬盘数据,为了提高VxWorks5.5系统下IDE电子盘读写速度,提出了一种基于ICH7-M南桥芯片的DMA模式驱动软件的设计方法。该方法采用风河公司提供的磁盘驱动程序框架,设计了新的读写接口函数,新驱... 详细信息

在嵌入式实时操作系统中,经常需要实时读写硬盘数据,为了提高VxWorks5.5系统下IDE电子盘读写速度,提出了一种基于ICH7-M南桥芯片的DMA模式驱动软件的设计方法。该方法采用风河公司提供的磁盘驱动程序框架,设计了新的读写接口函数,新驱动遵循ATA-6接口协议并采用UDMA2传输模式,可使电子盘读写速度提高十余倍。应用结果表明,该方法运行稳定,系统的实时性提高,充分发挥了电子盘性能。

关键词： VxWorks5.5 DMA 电子盘驱动

New insights into protein–polysaccharide complex coacervation:Dynamics,molecular parameters,and applications

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Aggregate 2024年第1期5卷 148-166页

作者： jiabao Zheng Paul Van der Meeren Weizheng Sun School of Food Science and Engineering South China University of TechnologyGuangzhouChina Department of Green Chemistry and Technology Faculty of Bioscience EngineeringGhent UniversityGhentBelgium Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health(111 Center) GuangzhouChina

For more than a decade,the discovery of liquid–liquid phase separation within living organisms has prompted colloid scientists to understand the connection between coacervate functionality,phase behavior,and dynamics at a multidisciplinary *** the protein–polysaccharide was the first system in which the coacervation phenomenon was discovered and is widely used in food systems,the phase state and relaxation dynamics of protein–polysaccharide complex coacervates(PPCC)have rarely been discussed ***,this review aims to unravel the relationship between PPCC dynamics,thermodynamics,molecular architecture,applications,and phase states in past *** ahead,solving the way molecular architecture spreads to macro-functionality,that is,establishing the relationship between molecular architecture–dynamics–application,will catalyze novel advancements in PPCC research within the field of foods and biomaterials.

关键词： dynamics encapsulation liquid coacervate protein-polysaccharide complex coacervation solid precipitate