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Fault diagnosis model based on multi-manifold learning and PSO-SVM for machinery

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仪器仪表学报 2014年第S2期35卷 210-214页

作者： wang Hongjun Xu Xiaoli Rosen b G Key Laboratory of Modern Measurement & Control Technology Beijing Information Science & Technology University School of Mechanic and Electric Engineering Beijing Information Science&Technology University Halmstad University

Fault diagnosis technology plays an important role in the industries due to the emergency fault of a machine could bring the heavy lost for the people and the company. A fault diagnosis model based on multi-manifold learning and particle swarm optimization support vector machine(PSO-SVM) is studied. This fault diagnosis model is used for a rolling bearing experimental of three kinds faults. The results are verified that this model based on multi-manifold learning and PSO-SVM is good at the fault sensitive features acquisition with effective accuracy.

关键词： fault diagnosis multi-manifold learning particle swarm optimization support vector machine

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掺杂对单层石墨烯纳米梁振动频率的影响

原子与分子物理学报 2025年第3期42卷 67-71页

作者：王志钦王静新疆大学物理科学与技术学院乌鲁木齐830017

石墨烯优异的力学和电学等性能,使其成为纳米机电谐振器的理想材料.通过分子动力学模拟方法研究了掺杂元素和掺杂浓度对单层石墨烯纳米梁振动特性的影响.研究结果表明,单层石墨烯纳米梁的振动频率随纳米梁长度的增加而减小,硼(b)掺杂、... 详细信息

石墨烯优异的力学和电学等性能,使其成为纳米机电谐振器的理想材料.通过分子动力学模拟方法研究了掺杂元素和掺杂浓度对单层石墨烯纳米梁振动特性的影响.研究结果表明,单层石墨烯纳米梁的振动频率随纳米梁长度的增加而减小,硼(b)掺杂、硼-硼(b-b)掺杂、铍(be)掺杂和铍-铍(be-be)掺杂均会导致单层石墨烯纳米梁的振动频率降低.此外,随着硼(b)/铍(be)掺杂浓度的增加,单层石墨烯纳米梁的振动频率逐渐降低.且随着掺杂浓度的增加,硼(b)掺杂石墨烯纳米梁的振动频率和铍(be)掺杂石墨烯纳米梁的振动频率的差异逐渐增大.这对石墨烯纳米机械谐振器、振荡器等纳米器件的设计具有一定的理论指导意义.

关键词：石墨烯振动频率分子动力学

Computer-based Creativity Enhanced Conceptual Design Model for Non-routine Design of Mechanical Systems

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Chinese Journal of Mechanical Engineering 2014年第6期27卷 1083-1098页

作者： LI Yutong wang Yuxin DUFFY Alex H b Department of Mechanical & Electrical Engineering China University of Petroleum Design Manufacture and Engineering ManagementUniversity of Strathclyde

Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure（FbS） model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model（CECD） for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FbS model are decomposed into and represented with fine-grain basic operation actions（bOA）, and the corresponding bOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with bOAs, the bOA set in the structure domain is formed. Through rule-based dynamic partition of the bOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. by adjusting the tightness of the partition rules and the granularity of the divided bOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.

关键词： conceptual design non-routine design creative enhance model computer-based approach mathematical expression

A Novel Sample Introduction Technique for the Simultaneous Determination of As,Se,Ge and Hg in Chinese Medicinal Material

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Chemical Research in Chinese Universities 2001年第4期17卷 400-406页

作者： Chen, b Zhuang, ZX wang, XR Lee, FSC Xiamen Univ Dept Chem Minist Educ China Key Lab Analyt Sci Xiamen 361005 Peoples R China

A novel technique of Moveable Reduction bed Hydride Generator（MRbHG）was applied tohe hydride generation or cold vapor generation of As，Se，Ge，and Hg existing In TraditionalChinese Medicinal Material（TCM）．The simultaneous determination of the multi－elements wasperformed with ICP－MS．A solid reduction system involving the use of potassiumtetraborohydride and tartaric acid was applied to generating metal hydride or cold *** factors affecting the metal cold vapor generation were *** mainadvantage of the technique is that only a 4μL volume of sample was required for the cold vapor

关键词： for the Simultaneous Determination of As,Se,Ge A Novel Sample Introduction Technique Chinese Material Medicinal and Hg Ge

Rheological properties and concentration evolution of thickened tailings under the coupling effect of compression and shear

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 862-876页

作者： Aixiang Wu Zhenqi wang Zhuen Ruan Raimund bürger Shaoyong wang Yi Mo Key Laboratory of the Ministry of Education of China for High-efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China CI2MA and Departamento de Ingeniería Matemática Facultad de Ciencias Físicas y MatemáticasUniversidad de ConcepciónCasilla 160-CConcepciónChile School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China China Railway Construction Tongguan Investment Co. Ltd.Tongling 244000China

Cemented paste backfill(CPb)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPb ***,difficult flocculation and substandard concentrations of thickened tailings often *** rheological properties and concentration evolution in the thickened tailings remain ***,traditional indoor thickening experiments have yet to quantitatively characterize their rheological *** experiment of flocculation condition optimization based on the box-behnken design(bbD)was performed in the study,and the two response values were investigated:concentration and the mean weighted chord length(MWCL)of ***,optimal flocculation conditions were *** addition,the rheological properties and concentration evolution of different flocculant dosages and ultrafine tailing contents under shear,compression,and compression-shear coupling experimental conditions were tested and *** results show that the shear yield stress under compression and compression-shear coupling increases with the growth of compressive yield stress,while the shear yield stress increases slightly under *** order of shear yield stress from low to high under different thickening conditions is shear,compression,and compression-shear *** compression and compression-shear coupling,the concentration first rapidly increases with the growth of compressive yield stress and then slowly increases,while concentration increases slightly under *** order of concentration from low to high under different thickening conditions is shear,compression,and compression-shear ***,the evolution mechanism of the flocs and drainage channels during the thickening of the thickened tailings under different experimental conditions was revealed.

关键词： thickened tailings compression-shear coupling compressive yield stress shear yield stress concentration

An analytical model for electrode-ceramic interaction in multilayer piezoelectric actuators

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Acta Mechanica Sinica 2007年第2期23卷 199-208页

作者： b.L.wang J.C.Han Center for Composite Materials Harbin Institute of TechnologyHarbin 150001China

The present paper develops an analytical model for multi-electrodes in multi-layered piezoelectric actuators, in which the electrodes are vertical to and terminated at the edges of the medium and electroelastic field concentrations ahead of the electrodes in the multilayer piezoelectric actuators are examined. by considering a representative unit in realistic multilayers, the problem is formulated in terms of electric potential between the electrode tips and results in a system of singular integral equations in which the electric potential is taken as unknown function. Effects are investigated of electrode spacing and piezoelectric coupling on the singular electroelastic fields at the electrode tips, and closed-form expressions are given for the electromechanical field near the electrode tips. Exact solution for un-coupled dielectrics is provided, where no piezoelectric coupling is present.

关键词： Actuators . Piezoelectric materials . Electrodes. Multilayer. Fracture mechanics

miR-338-3p靶向核因子κb受体活化因子配体影响牙槽骨成骨细胞增殖及凋亡

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中国组织工程研究 2025年第5期29卷 899-907页

作者：朗么磋张义林汪莉双流区第一人民医院(四川大学华西空港医院)口腔科四川省成都市621000

背景:miR-338-3p能够抑制破骨细胞分化,下调核因子κb受体活化因子配体水平能够促进骨形成。然而miR-338-3p是否通过调控核因子κb受体活化因子配体表达影响牙槽骨成骨细胞增殖、凋亡尚不清楚。目的:探究miR-338-3p靶向核因子κb受体活... 详细信息

背景:miR-338-3p能够抑制破骨细胞分化,下调核因子κb受体活化因子配体水平能够促进骨形成。然而miR-338-3p是否通过调控核因子κb受体活化因子配体表达影响牙槽骨成骨细胞增殖、凋亡尚不清楚。目的:探究miR-338-3p靶向核因子κb受体活化因子配体对牙槽骨成骨细胞增殖、凋亡的影响及机制。方法:分离人牙槽骨成骨细胞,对其进行细胞转染及Wnt-C59(Wnt/β-catenin通路抑制剂)处理,分为转染对照组、miR-338-3p组、miR-338-3p+对照组、miR-338-3p+核因子κb受体活化因子配体组和miR-338-3p+Wnt-C59组。双荧光素酶实验验证miR-338-3p对核因子κb受体活化因子配体的调控作用;CCK-8、EdU染色检测细胞增殖水平;流式细胞术检测细胞周期和凋亡水平;RT-qPCR检测细胞miR-338-3p、核因子κb受体活化因子配体、Wnt-3a、β-catenin、糖原合酶激酶3βmRNA表达水平;Western blot检测细胞核因子κb受体活化因子配体、增殖细胞核抗原、Ki67、细胞周期蛋白D1、bcl-2、bax、天冬氨酸半胱氨酸蛋白酶3、Wnt-3a、β-catenin、糖原合酶激酶3β蛋白表达水平。结果与结论:①miR-338-3p靶向调控核因子κb受体活化因子配体;②过表达miR-338-3p后,细胞存活率、EdU阳性细胞率、S期细胞比例升高,细胞凋亡率降低,miR-338-3p、增殖细胞核抗原、Ki67、细胞周期蛋白D1、bcl-2、Wnt-3a、β-catenin mRNA和蛋白水平升高,bax、天冬氨酸半胱氨酸蛋白酶3、核因子κb受体活化因子配体、糖原合酶激酶3βmRNA和蛋白水平降低(均Pb受体活化因子配体或Wnt-C59处理能够减弱过表达miR-338-3p对细胞增殖、凋亡的影响(均Pb受体活化因子配体表达可促进牙槽骨成骨细胞增殖,并抑制细胞凋亡,其可能通过激活Wnt/β-catenin信号通路发挥作用。

关键词： miR-338-3p 核因子κb受体活化因子配体牙槽骨成骨细胞 Wnt/β-catenin信号通路

Strong and ductile Mg alloys developed by dislocation engineering

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Journal of Materials Science & Technology 2019年第3期35卷 394-395页

作者： M.wang b.b.He M.X.Huang Department of Mechanical Engineering The University of Hong Kong Shenzhen Institute of Research and Innovation The University of Hong Kong

Dislocation engineering concept has been successfully employed to tackle the strength-ductility trade-off in steels, resulting in the development of high-strength high-ductility deformed and partitioned(D&P)steel. The present perspective proposes to employ such dislocation engineering concept to develop strong and ductile magnesium(Mg) alloys. High density of dislocations could be generated at appropriate temperature and retained in the Mg alloy after quenching to room temperature. Those dislocations inherited from the warm deformation could provide dislocation sources when the Mg alloy is deformed at room temperature, resulting in good ductility. The high dislocation density generated at warm deformation provides dislocation forest hardening, leading to improved yield strength of Mg alloy.

关键词： Dislocation engineering Mg alloys Warm rolling Strength and ductility

Quantum phase transition in quarter-filled nanoclusters of manganite induced by element substitution at b site

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1277-1282页

作者： wang HaiLong wang RongMing wang YuGang TIAN GuangShan School of Physics Peking University Beijing 100871 China Key Laboratory of Micro-nano Measurement-Manipulation and Physics (Ministry of Education) Department of Physics Beijing University of Aeronautics & Astronautics Beijing 100191 China

In the present paper,we study the effect of element substitution for quarter-filled nanoclusters of perovskite manganite by introducing Jahn-Teller type of perturbation interaction to the double-exchange *** the unrestricted real-space Hartree-Fock approximation method we find that,the Jahn-Teller electron-phonon interaction plays the central role in producing the phase transition from ferromagnetic phase to CE type antiferromagnetic *** only the Jahn-Teller interaction benefits antiferromagnetic correlation,it also increases the charge density order *** theoretical results provide a guidance to predict the properties and modify the composition of particles of perovskite manganite under nano-scale.

关键词： manganite charge ordered phases antiferromagnetic correlation