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Dynamic performance analysis model of high-reliability EMS-Maglev system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 412-415页

作者： FANG You-tong YAO ying-ying College of Electrical Engineering Zhejiang University Hangzhou 310027 China

In this paper, a modified transient finite element (FE) algorithm for the performance analysis of magnetically levitated vehicles of electromagnetic type is presented. The algorithm incorporates the external power system and vehicle’s movement equations into FE model of transient magnetic field computation directly. Sliding interface between stationary and moving region is used during the transient analysis. The periodic boundaries are implemented in an easy way to reduce the computation scale. It is proved that this method can be used for both electro-motional static and dynamic cases. The test of a transformer and an EMS-Maglev system reveals that the method generates reasonable results at very low computational costs comparing with the transient FE analysis.

关键词： EMS-Maglev system Field-circuit coupled Movement finite element

ANNEALED IMPORTANCE SAMplING FOR ISING MODELS WITH MIXED BOUNDARY CONDITIONS

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Journal of Computational Mathematics 2023年第3期41卷 542-550页

作者： Lexing ying Department of Mathematics Stanford UniversityStanfordCA 94305USA

This note introduces a method for sampling Ising models with mixed boundary *** an application of annealed importance sampling and the Swendsen-Wang algorithm,the method adopts a sequence of intermediate distributions that keeps the temperature fixed but turns on the boundary condition *** numerical results show that the variance of the sample weights is relatively small.

关键词： Ising model Annealed importance sampling Swendsen-Wang algorithm

Light People:Professor Jianhua Jiang

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Light(Science & Applications) 2022年第1期11卷 7-12页

作者： ying Zhang Light Publishing Group Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences3888 Dong Nan Hu Road130033 ChangchunChina

Recently,*** Jiang from Soochow University of China accepted an interview from Light:Science&*** works on topological photonics,topological phononics,and nonequilibrium *** this issue,he discusses the challenges and opportunities in topological photonics,topological phononics,and other topological synthetic *** also shares his experiences in cutting-edge research,the education of graduate students,and other challenges faced by junior ***,he gives remarks and suggestions for Light:Science&*** People is a featured column of high-end interviews with outstanding *** is our great honor to invite *** Jiang,an outstanding young scientist,to showcase his research life and the story behind his success.

关键词： topological nonequilibrium interview

Investigation of Adsorption of Xanthan Gum on Enamel by Tapping Mode Atomic Force Microscopy

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Chemical Research in Chinese Universities 2004年第4期20卷 501-503页

作者： LIHao-ying DepartmentofOralandDentalScience BiomedicalEngineeringandBiomaterialsScienceSectionUniversityofBristolLowerMaudlinStreetBristolBS12LY

By using tapping mode atomic force microscopy(TMAFM), a polymer layer was found on the enamel surface after the exposure to xanthan gum solutions. The layer thickness is closely related to the exposure time and the concentration of xanthan gum solution. The thickness data were evaluated by a Kruskal-Wallis test and Box-Whisker plot at a 95% confidence level(pying agents in the beverage might be adsorbed on the enamel surface during consumption, which may form a barrier that can protect the enamel from being attacked by acid and therefore reduce dental erosion.

关键词： Atomic force microscopy(AFM) Vertical distance Xanthan gum Enamel

Multi-angle Face Detection Based on DP-Adaboost

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International Journal of Automation and computing 2015年第4期12卷 421-431页

作者： ying-ying Zheng Jun Yao School of Mechanical and Electronic Engineering and Automation Shanghai University

Although important progresses have been already made in face detection,many false faces can be found in detection results and false detection rate is influenced by some factors,such as rotation and tilt of human face,complicated background,illumination,scale,cloak and *** paper proposes a new method called DP-Adaboost algorithm to detect multi-angle human face and improve the correct detection *** improved Adaboost algorithm with the fusion of frontal face classifier and a profile face classifier is used to detect the multi-angle *** improved horizontal differential projection algorithm is put forward to remove those non-face images among the preliminary detection results from the improved Adaboost *** results show that compared with the classical Adaboost algorithm with a frontal face classifier,the textual DP-Adaboost algorithm can reduce false rate significantly and improve hit rate in multi-angle face detection.

关键词： Multi-angle face detection Adaboost classifier fusion improved horizontal differential projection false face.

单层Cs_(2)PbI_(2)Cl_(2)中点缺陷的形成与稳定性

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原子与分子物理学报 2025年第5期42卷 130-136页

作者：何诗颖赵宇清邹代峰许英廖雨洁禹卓良湖南科技大学物理与电子科学学院湘潭411201 智能传感器与新型传感器材料湖南省重点实验室湘潭411201 湖南理工学院物理与电子科学学院岳阳414006

Cs_(2)PbI_(2)Cl_(2)是卤化铅钙钛矿材料的新成员,由于其高的光吸收系数和长的载流子迁移距离等优异的光电物理性能,在太阳能电池、光电探测器、场效应晶体管以及发光二极管等领域受到广泛的关注.其中光电材料及器件的优良特性由电子结... 详细信息

Cs_(2)PbI_(2)Cl_(2)是卤化铅钙钛矿材料的新成员,由于其高的光吸收系数和长的载流子迁移距离等优异的光电物理性能,在太阳能电池、光电探测器、场效应晶体管以及发光二极管等领域受到广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而钙钛矿的点缺陷对电子结构具有重要的调控,且单层Cs_(2)PbI_(2)Cl_(2)中点缺陷的研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对单层Cs_(2)PbI_(2)Cl_(2)的铯空位、碘空位、氯空位、铯替代铅、碘替代铯、碘替代铅、碘替代氯、氯替代铯、氯替代铅和氯替代碘的缺陷形成能和稳定性进行了研究.结果表明:在富铅和缺铅条件下,碘替代氯和氯替代碘的缺陷形成能偏低,且氯替代碘能有效降低体系总能,提高体系稳定性.在缺铅条件下铯空位缺陷形成能低于富铅条件,在缺铅条件下更易形成铯空位;富铅和缺铅条件下对碘替代氯和氯替代碘的缺陷形成能基本无影响.上述研究结果有助于理解点缺陷对钙钛矿材料稳定性的影响,同时也为未来实验上设计基于Cs_(2)PbI_(2)Cl_(2)的高效的光电子器件提供理论依据.

关键词：单层Cs_(2)PbI_(2)Cl_(2) 形成能点缺陷稳定性

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Unsteady analysis of six-DOF motion of a 6:1 prolate spheroid in viscous fluid

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Science China(Physics,Mechanics & Astronomy) 2017年第11期60卷 24-40页

作者： ying Xiong ying Xiong Hui Guan ChuiJie Wu The Unite 91550 of People's Liberation Army of China Dalian 112023 China School of Aeronautics and Astronautics Dalian University of Technology Dalian 112024 China College of Meteorology and Oceanography National University of Defense Technology Nanjing 211101 China

Free-moving simulations of airplanes, submarines and other automobiles under extreme and emergency conditions are becoming increasingly important from operational and tactical perspectives. Such simulations are fairly challenging due to the extreme unsteady motions and high Re(Reynolds) numbers. The aim of this study is to perform a six-DOF motion simulation of a 6:1prolate spheroid that is falling in a fluid field. Prior to conducting the six-DOF simulation, some verification simulations were performed. First, a laminar flow past an inclined prolate spheroid at a Re number of 1000 and incidence angle of 45. with a tetrahedral mesh was simulated to verify the relevant targeted discrete method for an unstructured mesh. Second, to verify the LES(large eddy simulation) models and dependent parameters for the DDES(delayed detached eddy simulation), a turbulent flow past a sphere was performed at a subcritical Re number of 10000. Third, a steady maneuvering problem about a prolate spheroid pitching up from 0. to 30. incidence at a uniform angular velocity was established based on a dynamic tetrahedral mesh with changing topology and the ALE(arbitrary Lagrangian-Eulerian) method of fluid-structure coupling at a Re number of 4.2 × 10~***, two six-DOF motions of an inclined 6:1 prolate spheroid at an initial incidence of 45. were simulated at different Re numbers of 10000 and 4.2 × 10~6.

关键词： unsteady six-DOF tetrahedral dynamic mesh discrete method DDES

Dynamic modeling and simulation test of a 60 kW PEMFC generation system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第6期12卷 475-482页

作者： ying-ying ZHANG Ji-chang SUN ying ZHANG Xi LI Ouang-yi CAO Shandong Provincial Key Laboratory of Ocean Environment Monitoring Technology Shandong Academy of Sciences Institute of Oceanographic Instrumentation Qingdao 266001 China Control Science and Engineering Department Key Laboratory of Education Ministry for Image Processing and lntelligent Control Huazhong University of Science & Technology Wuhan 430074 China Fuel Cell Institute Department of Automation Shanghai Jiao Tong University Shanghai 200030 China

In this paper,a 60 kW proton exchange membrane fuel cell(PEMFC) generation system is modeled in order to design the system parameters and investigate the static and dynamic characteristics for control *** achieve an overall system model,the system is divided into five modules:the PEMFC stack(anode and cathode flows,membrane hydration,and stack voltage and power),cathode air supply(air compressor,supply manifold,cooler,and humidifier),anode fuel supply(hydrogen valve and humidifier),cathode exhaust exit(exit manifold and water return),and power conditioning(DC/DC and DC/AC) *** a combination of empirical and physical modeling techniques,the model is developed to set the operation conditions of current,temperature,and cathode and anode gas flows and pressures,which have major impacts on system *** current model is based on a 60 kW PEMFC power plant designed for residential applications and takes account of the electrochemical and thermal aspects of chemical reactions within the stack as well as flows of reactants across the *** simulation tests show that the system model can represent the static and dynamic characteristics of a 60 kW PEMFC generation system,which is mathematically simple for system parameters and control designs.

关键词： Proton exchange membrane fuel cell(PEMFC) Generation system Dynamic simulation model Reactant flow

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体相二硫化铼中点缺陷的形成与稳定性

原子与分子物理学报 2025年第5期42卷 143-150页

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要... 详细信息

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要的调控,且体相二硫化铼的缺陷研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对体相二硫化铼的铼空位、硫空位、钨掺杂(或替代)铼、钨掺杂硫、锝掺杂铼和锝掺杂硫的缺陷形成能和稳定性进行了研究.结果表明:钨掺杂硫和锝掺杂硫形成深施主能级缺陷,铼空位形成浅施主能级缺陷.在富铼和富硫条件下,钨掺杂铼的缺陷形成能低且能有效降低体系总能,提高体系稳定性.钨掺杂硫的缺陷虽然能降低体系的总能提高二硫化铼的稳定性,但较大的缺陷形成能表明钨掺杂硫缺陷难以形成.上述研究结果有助于理解缺陷能级对半导体深浅能级和稳定性的影响,同时也为未来实验上设计基于二硫化铼的高效的光电子器件提供理论依据.

关键词：体相二硫化铼形成能缺陷能级稳定性