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Frontiers in Energy 2024年第2期18卷 241-262页

作者： Zeyu WANG yanru LIU Shun chen Yun ZHENG xiaogang FU yan ZHANG Wanglei WANG State Key Laboratory of Solidification Processing Atomic Control and Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of Dental MaterialsSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

Proton exchange membrane fuel cells(PEMFCs)are playing irreplaceable roles in the construction of the future sustainable energy ***,the insufficient performance of platinum(Pt)-based electrocatalysts for oxygen reduction reaction(ORR)hinders the overall efficiency of *** the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic *** this paper,insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in ***,recent advances in understanding the strain effects on ORR catalysts are comprehensively ***,strain engineering methodologies for adjusting Ptbased catalysts are comprehensively ***,further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided.

关键词： strain engineering Pt-based catalysts oxygen reduction reaction(ORR) catalytic performance proton exchange membrane fuel cells(PEMFCs)

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未来空战全域火力场研究

航空学报 2024年第5期45卷 288-305页

作者：谢岚风陈军焦璐李函之王鹏陈双航空工业成都飞机设计研究所成都610091 西北工业大学电子信息学院西安710072

分析了未来穿透性制空(PCA)空战的发展趋势和制胜关键,针对PCA全平台隐身和分布式杀伤两大显著特征,首先,基于“以目标为中心”和“以载机为中心”2种全向攻击火控模式的有机融合和优势互补,在贯穿导弹射前、射后,覆盖多机、多弹、多目... 详细信息

分析了未来穿透性制空(PCA)空战的发展趋势和制胜关键,针对PCA全平台隐身和分布式杀伤两大显著特征,首先,基于“以目标为中心”和“以载机为中心”2种全向攻击火控模式的有机融合和优势互补,在贯穿导弹射前、射后,覆盖多机、多弹、多目标的全时空域框架下,提出了从全局多层次视角反映协同空战多火力节点的动态和综合杀伤性能的穿透性制空全域火力场概念和设计原理,重新定义了基于截获概率及其全概率公式的空空导弹时变杀伤性能模型,并依此建立了单机火力场模型和双机火力场聚合模型;其次,通过引入场理论的“梯度、散度和旋度”3个度量指标,分别建立了火力场的空间分布、作用范围和偏转变化特性表征模型,并进行了相应的火力场仿真与特性分析;最后,初步探索了将全域火力场应用于全向攻击观察-判断-决策-行动(OODA)闭环的火控瞄准与操纵、单机隐身穿透掠袭式和双机编组协同攻击2种典型空战战术等场景的情况,证明了这一新质火控原理具备很好的技术优势和应用潜力。上述研究工作对于充分发挥新式武器装备性能,有效提高载机自由攻击和自由脱离能力,提升空战效能具有重要的作用;同时,可为将来空战分布式杀伤网的敏捷构建、杀伤链的动态组合和新型战术战法的分析等问题研究提供理论支撑和技术参考。

关键词：全域火力场穿透性制空全向攻击梯度散度旋度

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高性能运动控制在数控系统中的应用综述

信息与控制 2003年第3期32卷 245-250页

作者：王军平王安敬忠良陈全世清华大学汽车工程系汽车安全与节能国家重点实验室北京100084 西北工业大学自动控制系西安710072 上海交通大学航空航天信息与控制研究所上海200030

分析了在高速高精度加工中设计高性能运动控制器时存在的问题及面临的挑战 ,评述了高性能数控系统运动控制器设计方法的发展现状。

关键词：数控系统数控机床加工中心柔性制造单元高性能运动控制

Mechanical behavior and failure mechanism of polyurea nanocomposites under quasi-static and dynamic compressive loading

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Defence Technology（防务技术） 2021年第2期17卷 495-504页

作者： Qiang Liu Peng-wan chen yan-song Guo Jian-jun Su Lu Han Ali Arab Jian-fei Yuan State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China xi’an Modern Chemistry Research institute Xi’an 710065China

Polyurea is an elastomeric material that can be applied to enhance the protection ability of structures under blast and impact *** order to study the compressive mechanical properties of SiC/polyurea nanocomposites under quasi-static and dynamic loading,a universal testing machine and split Hopkinson pressure bar(SHPB)apparatus were used *** stress-strain curves were obtained on polyurea and its composites at strain rates of 0.001e8000 s*** results of the experiment suggested that increase in the strain rates led to the rise of the flow stress,compressive strength,strain rate sensitivity and strain *** indicates that all of the presented materials were dependent on strain ***,these mechanical characters were enhanced by incorporating a small amount of SiC into polyurea *** relation between yield stress and strain rates were established using the power law ***,in order to investigate the fracture surfaces and inside information of failed specimens,scanning electron microscopy(SEM)and micro X-ray computed tomography(micro-CT)were used *** voids,crazes,micro-cracks and cracking were observed in fracture *** the other hand,the cracking propagation was found in the micro-CT slice *** is essential to understand the deformation and failure mechanisms in all the polyurea materials.

关键词： Polyurea nanocomposites Mechanical properties Strain rate Micro-CT Failure

单颗磨粒切削TC4钛合金过程摩擦行为仿真与研究

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钛工业进展 2024年第2期41卷 35-40页

作者：陈振赵盼闫蕊路丹妮西安航空学院机械工程学院陕西西安710077 西安明德理工学院智能制造与控制技术学院陕西西安710124 西北工业大学航空发动机高性能制造工业和信息化部重点实验室陕西西安710072

通过有限元仿真软件研究了单颗磨粒在切削TC4钛合金过程中的摩擦行为及其对抛光加工的影响。利用Abaqus软件建立了单颗磨粒切削TC4钛合金过程中材料的塑性变形模型,并应用迭代自适应网格重划分技术,准确模拟了不同摩擦系数下单颗磨粒切... 详细信息

通过有限元仿真软件研究了单颗磨粒在切削TC4钛合金过程中的摩擦行为及其对抛光加工的影响。利用Abaqus软件建立了单颗磨粒切削TC4钛合金过程中材料的塑性变形模型,并应用迭代自适应网格重划分技术,准确模拟了不同摩擦系数下单颗磨粒切削TC4钛合金表面时的接触应力分布和塑性变形,为优化TC4钛合金叶片抛光工艺提供了理论依据。研究表明,摩擦系数对切削深度和材料堆积率有影响,特别是在磨粒切出阶段,摩擦系数的增加会显著促进材料在磨粒前端和两侧的堆积,故在实际抛光加工中应合理控制摩擦系数。

关键词：单颗磨粒有限元仿真塑性变形材料堆积率摩擦行为

Review of Recent Progress in Robotic Knee Prosthesis Related Techniques:Structure,Actuation and control

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Journal of Bionic Engineering 2021年第4期18卷 764-785页

作者： Yuanxi Sun Hao Tang Yuntao Tang Jia Zheng Dianbiao Dong xiaohong chen Fuqiang Liu Long Bai Wenjie Ge Liming xin Huayan Pu yan Peng jun Luo State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China School of Mechanical Engineering Tianjin UniversityTianjin 300072China College of Mechanical Engineering Chongqing UniversityChongqing 400044China School of Advanced Manufacturing Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering Vrije Universiteit Brussel1050 BrusselsBelgium Department of Mechanical&Industrial Engineering University of TorontoToronto M5S 2E8Canada Research institute of Unmanned Surface Vessel(USV)Engineering Shanghai UniversityShanghai 200444China

As the essential technology of human-robotics interactive wearable devices,the robotic knee prosthesis can provide above-knee amputations with functional knee compensations to realize their physical and psychological social *** the development of mechanical and mechatronic science and technology,the fully active knee prosthesis that can provide subjects with actuating torques has demonstrated a better wearing performance in slope walking and stair ascent when compared with the passive and the semi-active ***,with intelligent human-robotics control strategies and algorithms,the wearing effect of the knee prosthesis has been greatly enhanced in terms of stance stability and swing ***,to help readers to obtain an overview of recent progress in robotic knee prosthesis,this paper systematically categorized knee prostheses according to their integrated functions and introduced related research in the past ten years(2010−2020)regarding(1)mechanical design,including uniaxial,four-bar,and multi-bar knee structures,(2)actuating technology,including rigid and elastic actuation,and(3)control method,including mode identification,motion prediction,and automatic *** and qualitative analysis and comparison of robotic knee prosthesis-related techniques are *** development trends are concluded as follows:(1)bionic and lightweight structures with better mechanical performance,(2)bionic elastic actuation with energy-saving effect,(3)artificial intelligence-based bionic prosthetic ***,challenges and innovative insights of customized lightweight bionic knee joint structure,highly efficient compact bionic actuation,and personalized daily multi-mode gait adaptation are also discussed in-depth to facilitate the future development of the robotic knee prosthesis.

关键词： bionic robotic knee prosthesis prosthetic knee mechanism actuation control

Investigation of micro vortex generators on controlling flow separation over SCCH high-lift configuration

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Science China(Technological Sciences) 2012年第8期55卷 1943-1953页

作者： CHU HuBing ZHANG BinQian chen YingChun LI YaLin MAO jun School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Commercial Aircraft Corporation of China Ltd Shanghai Aircraft Design and Research InstituteShanghai 200235China

For the problem that the flow separation on the flap lowers the aerodynamic performance of high lift system,an investigation was carried out on using micro vortex generators(VGs) to control the separation on flap of the swept constant chord half-model(SCCH) high-lift configuration,at a small to medium angle of attack,by experimental and numerical *** basic flow characteristics of SCCH landing configuration were analyzed by using numerical method to provide required information for the design of micro ***,by keeping the cruise configuration intact,the preliminary design procedure and design methods of micro VGs were *** addition,the micro VGs were *** effects of VG's arrangement and geometric parameters,such as the arrangement mode,chordwise position,arrangement angle,height and spanwise distance,on controlling efficiency were investigated by using numerical *** the parameters of preliminary VGs were adjusted as the basis configuration for wind tunnel *** experiments were accomplished in NH-2 wind tunnel for validating the numerical method,as well as obtaining the design principles and methods of micro *** parameters of VGs were also optimized based on the *** experimental results showed that the numerical design method can serve as an efficient and accurate design *** lift and drag were increased by 10% and 14%,respectively in landing state,which satisfied the requirements for ***,it was concluded that the established design principles and methods for micro VGs in this investigation can be used in engineering application.

关键词： micro vortex generators high lift system flow control numerical simulation wind tunnel test

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基于模糊灰色认知图的复杂战场智能态势感知建模方法

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兵工学报 2022年第5期43卷 1093-1106页

作者：陈军张岳陈晓威佟龑西北工业大学电子信息学院陕西西安710072 江苏自动化研究所江苏连云港222061

针对复杂战场环境的动态、不确定性特征,提出一种基于模糊灰色认知图(FGCM)的智能态势感知(SA)建模方法。基于SA理论,采用自上而下任务驱动的态势觉察方式实现态势元素的提取;以目标威胁评估为态势理解的建模对象,利用FGCM在不确定数据... 详细信息

针对复杂战场环境的动态、不确定性特征,提出一种基于模糊灰色认知图(FGCM)的智能态势感知(SA)建模方法。基于SA理论,采用自上而下任务驱动的态势觉察方式实现态势元素的提取;以目标威胁评估为态势理解的建模对象,利用FGCM在不确定数据表达和推理的模型特性,同时引入外部环境控制节点建立威胁评估动态FGCM模型。以目标意图预测为态势预测的建模对象,在基于专家知识建立的FGCM模型结构基础上,采用粒子群优化算法提高了意图预测模型对历史数据样本的参数学习能力。仿真验证分析结果表明,基于FGCM的智能SA建模方法能够较好地应对动态、不确定的战场环境,发挥知识和数据在建模中的综合作用。

关键词：态势感知威胁评估意图预测模糊灰色认知图粒子群优化算法

Small P values may not yield robust findings:an example using REST-meta-PD

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Science Bulletin 2021年第21期66卷 2148-2152,M0003页

作者： xi-Ze Jia Na Zhao Hao-Ming Dong Jia-Wei Sun Marek Barton Roxana Burciu Nicolas Carrière Antonio Cerasa Bo-Yu chen jun chen Stephen Coombes Luc Defebvre Christine Delmaire Kathy Dujardin Fabrizio Esposito Guo-Guang Fan Federica Di Nardo Yi-Xuan Feng Brett W.Fling Saurabh Garg Moran Gilat Martin Gorges Shu-Leong Ho Fay BHorak xiao Hu xiao-Fei Hu Biao Huang Pei-Yu Huang Ze-Juan Jia Christina Jones Jan Kassubek Lenka Krajcovicova Ajay Kurani Jing Li Qing Li Ai-Ping Liu Bo Liu Hu Liu Wei-Guo Liu Renaud Lopes Yu-Ting Lou Wei Luo Tara Madhyastha Ni-Ni Mao Grainne McAlonan Martin J.McKeown Shirley Pang Andrea Quattrone Irena Rektorova Alessia Sarica Hui-Fang Shang James M.Shine Priyank Shukla Tomas Slavicek xiao-Peng Song Gioacchino Tedeschi Alessandro Tessitore David Vaillancourt Jian Wang Jue Wang Z.Jane Wang Lu-Qing Wei xia Wu xiao-jun Xu Lei yan Jing yang Wan-Qun yang Nai-Lin Yao De-Long Zhang Jiu-Quan Zhang Min-Ming Zhang yan-Ling Zhang Cai-Hong Zhou Chao-Gan yan xi-Nian Zuo Mark Hallett Tao Wu Yu-Feng Zang Center for Cognition and Brain Disorders the Affiliated HospitalHangzhou Normal UniversityHangzhou 310015China Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments Hangzhou 311121China National Basic Science Data Center Beijing 100190China State Key Laboratory of Cognitive Neuroscience and Learning&McGovern institute for Brain Research Beijing Normal UniversityBeijing 100875China School of information and Electronics Technology Jiamusi UniversityJiamusi 154007China Neuroscience Program Central European Institute of TechnologyCEITECMasaryk UniversityBrno 62500Czech Republic Department of Applied Physiology and Kinesiology University of FloridaGainesville FL 32611USA Univ.Lille InsermCHU LilleU1172-LilNCog-Lille Neuroscience&CognitionLille F-59000France The institute for Biomedical Research and Innovation National Research CouncilMangone CS 87050Italy Department of Radiology The First Affiliated Hospital of China Medical UniversityShenyang 110001China Department of Radiology Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120China Department of Medicine Surgery and DentistryScuola Medica SalernitanaUniversity of SalernoFiscianoSA 132-84084Italy Department of Advanced Medical and Surgery Sciences University of Campania“Luigi Vanvitelli”Caserta 81100Italy Eye Center of the 2nd Affiliated Hospital Medical College of Zhejiang UniversityHangzhou 310020China Zhejiang Provincial Key Lab of Ophthalmology Hangzhou 310020China Department of Health and Exercise Science Colorado State UniversityFort Collins CO 80523USA Pacific Parkinson’s Research Centre University of British ColumbiaVancouver BC V6E 2M6Canada Department of Medicine(Neurology)university of British Columbia Vancouver BC V6T 1B7Canada Brain and Mind Center The University of SydneySydney NSW 2006Australia Department of Neurology Ulm UniversityUlm 89081Germany Division of Neurology Department of MedicineQueen Mary HospitalUniversity of Hong KongHong Kong 999077China Department of

Thousands of resting state functional magnetic resonance imaging(RS-f MRI)articles have been published on brain *** precise localization of abnormal brain activity,a voxel-level comparison is *** of the large number of voxels in the brain,multiple comparison correction(MCC)must be performed to reduce false positive rates,and a smaller P value(usually including either liberal or stringent MCC)is widely recommended[1].

关键词：帕金森病 precise correction