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The main projects and development status of noise forecasting and controlling on working face in coal mine

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Journal of Coal Science & Engineering(China) 2010年第2期16卷 198-205页

作者： PENG You-duo GUO Ying-fu WU Li-tao LI Xin XIE Wei-hua Dhillon B S hunan Provincial key laboratory of health maintenance for mechanical equipment Hunan University of Science and Technology Xiangtan 411201 China Department of mechanical Engineering of University of Ottawa Canada ON K1N 6N5 Canada

Noise from the machine on coal working face seriously influenced the miners' physical and mental health, and also, due to the noise, there may be a major hidden danger in safety from accidents as all safety warning signals may be masked by the noise. This paper summarized the features of mine environmental noise on working face, such as the variety of noise sources, the continuity of high intensity and slow attenuation in narrow space, *** main projects about noise forecasting and controlling on working face was emphatically expounded;the development status about mines machinery noise mechanism and environmental noise acoustic characteristics of space-time of these main research topics were also introduced.

关键词：煤矿工作面噪声控制噪声源预测矿山环境身心健康预警信号安全事故

The Influence of the Supporting Wheel Deflection of Large-scale Rotary Kiln on Maximum Contact Stress

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工程科学（英文版） 2006年第4期4卷 92-96页

作者： Li Xuejun Qiu Weiliang Yuan Yincai Li Ping health maintenance for mechanical equipment key lab of hunan province Hunan Science and Technology University Xiangtan Hunan 411201 School of mechanical and Electronic Central South University Hunan Changsha 410083

The relation between the maximum contact stress ratio and deflection angle is derived from Hertz contact theory when the deflection of rotary kiln supporting wheel happens. According to the analysis of practical example, the maximum contact stress ratio within the deflection range of rotary kiln supporting wheel is listed. The contact stress will increase largely when rotary kiln supporting wheel deflects with little angle, which probably will result in accidents correlating to safety. This will provide theory conference for the design, the operating condition analysis and adjusting of the rotary kiln.

关键词：回转窑接触面应力支护水泥冶金工程

Applications of Wigner high-order spectra in feature extraction of acoustic emission signals

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Engineering Sciences 2009年第3期7卷 59-65页

作者： Xiao Siwen Liao Chuanjun Li Xuejun key lab of health maintenance for mechanical equipment of hunan province Hunan Science and Technology University Xiangtan Hunan 411201 China Department of Precision Instruments Tsinghua University Beijing 100084 China

The characteristics of typical AE signals initiated by mechanical component damages are analyzed. Based on the extracting principle of acoustic emission(AE) signals from damaged components,the paper introduces Wigner high-order spectra to the field of feature extraction and fault diagnosis of AE signals. Some main performances of Wigner binary spectra,Wigner triple spectra and Wigner-Ville distribution (WVD) are discussed,including of time-frequency resolution,energy accumulation,reduction of crossing items and noise elimination. Wigner triple spectra is employed to the fault diagnosis of rolling bearings with AE techniques. The fault features reading from experimental data analysis are clear,accurate and intuitionistic. The validity and accuracy of Wigner high-order spectra methods proposed agree quite well with simulation results. Simulation and research results indicate that wigner high-order spectra is quite useful for condition monitoring and fault diagnosis in conjunction with AE technique,and has very important research and application values in feature extraction and faults diagnosis based on AE signals due to mechanical component damages.

关键词：声发射信号提取原理维格纳高阶谱应用声发射(AE)信号声发射技术故障诊断

The Application of Eddy Current Transducer for Testing Movement Locus of Shaker Screen

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工程科学（英文版） 2007年第1期5卷 85-89页

作者： Zhu Pingyu Lao Chuanjun Zhang Wei Li Xuejun key lab of health maintenance for mechanical equipment of hunan province Hunan University of Science and TechnologyXiangtanHunan411201 Xiangtan Colliery Machine Stock Ltd Xiangtan Hunan411201

Shaker screen is one of important equipments in the industry of oil, metallurgy, coal and timbering. The movement locus of shaker screen affects the capacity and efficiency of shaker screen to split the solid particle from crude ore directly. To test movement of shaker locus, two eddy current transducers are employed. A discussion of the usage of these eddy current transducer to test and acceleration sensors will be made. The experiment results from a real elliptic shaker screen have good agree with the design requirements.

关键词： shaker screen movement locus test eddy current transducer

Research on the characteristics of noise source on heading face and noise propagation in mine laneway

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Journal of Coal Science & Engineering(China) 2012年第4期18卷 418-422页

作者： PENG You-duo XIE Wei-hua XIE Zhi-yong PENG Chang-qing YIN Xi hunan Provincial key laboratory of health maintenance for mechanical equipment Hunan University of Science andTechnologyXiangtan 411201China Engineering Research Center of Advanced Mining equipment Ministry of EducationHunan University of Science and Tech-nologyXiangtan 411201China Loudi Vocational Technical College Loudi 417000China

Based on the complexity and dynamic random analysis of machine noise source in mine heading face, this article established the noise pressure mathematical model of noise propagation in mine laneway of different noise sources, carried out noise propagation numerical simulation in long space, and revealed noise propagation law of more radiated noise sources in the mine roadway. The results show that, under conditions that the total noise power is always the same, regardless of point source, surface noise source, or body noise source, the corresponding noise attenuation trend along the mine laneway and attenuation curve shape are basically the same. However, the attenuation velocity corresponding to complex stereo noise source is slower than single point source and the noise pressure value is higher than the single point source. The actual noise of measured values is close to the theoretical value or, say, there is little error for complex stereo noise source, whereas the error to single point source and surface noise is higher, respectively.

关键词：矿井巷道掘进工作面噪声传播噪声源随机分析数学模型数值模拟噪声功率

Study on quality evaluation model in multi-station assembly processes

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Engineering Sciences 2008年第4期6卷 25-30页

作者： Wen Zejun Liu Deshun Yang Shuyi hunan Provincial key lab of health maintenance for mechanical equipment Hunan University of Science and Technology Xiangtan Hunan 411201 China School of mechanical and Electrical Engineering Central South University Changsha 410083 China

Based on features of dimension variation propagation in multi-station assembly processes,a new quality evaluation model of assembly processes is established. Firstly,the error source of multi-station assembly system is analyzed,the relationship of dimension variation propagation in multi-station assembly processes is studied and the state equation for variation propagation is constructed too. Then,the feature parameters which influence variation propagation and accumulation in multi-station assembly processes are found to evaluate quality characteristic of the assembly system. Through the derivation of equation on dimension variation propagation,station coefficient matrices which are combined and conversed to determine the max eigenvalue are educed. The max eigenvalue is multiplied by the weight coefficient to establish the quality evaluation model in multi-station assembly processes. Furthermore,assembly variation indexes are proposed to judge of the assembly technology process. Finally,through the practical example,the application of the model and assembly variation indexes are presented.

关键词：质量评价模型装配工艺多工位最大特征值传播特征进程装配过程装配系统

Multi-component system maintenance optimization of a rail transit train based on opportunistic correlations

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Transportation Safety and Environment 2023年第4期5卷 182-191页

作者： Jisheng Dai Rongjun Ding Yong Fu Yong Qin College of mechanical and Vechicle Engineering Hunan UniversityYuelu DistrictChangshaHunan 410082China Zhuzhou CRRC Times Electric Co. Ltd.Shifeng DistrictZhuzhouHunan 412001China State key lab of Rail Traffic Control&Safety Beijing Jiaotong UniversityHaidian DistrictBeijing 100044China

ln order to deal with the problems of insufficient or excessive maintenance in the current maintenance activities of China transit trains,this paper develops a novel multi-component system maintenance optimization approach based on an opportunistic correlation *** on the minimal reliability and failure rate change rule of each train component,the novel proposed maintenance optimization benefits from an improved opportunistic maintenance model with system structure correlation,fault correlation and reliability correlation under imperfect ***,different maintenance modes can be determined by a proposed mainte-nance factor under the different conditions of ***,the reliability threshold of each component is also considered to optimize the maintenance cost by the system reliability and operational availability of the ***,as the mentioned problem belongs to the NP-Hard optimization problems,a modified particle swarm optimization(PSO)with the improvement of inertia weight is proposed to cope with the optimization *** on a specific case under the practical recorded failure data,the analysis shows that the proposed model and approach can effectively cut the maintenance cost.

关键词： multi-component system maintenance optimization rail transit train opportunistic correlation modified particle swarm optimization(PSO)

The integrated monitoring system for running parameters of key mining equipment based on condition monitoring technology

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Journal of Coal Science & Engineering(China) 2010年第1期16卷 108-112页

作者： BIN Guang-fu LI Xue-jun BALBIR S Dhillon HUANG Zhen-yu GUO Deng-ta key lab of health maintenance for mechanical equipment of hunan province Hunan University of Science and Technology Xiangtan 411201 China Department of mechanical Eng. Univ/Ottawa Ottawa K1B 6N5 Canada Xiangtan Liangchuan Coal Mine Machine Co. Ltd. Xiangtan 411104 China Xiangtan Electric Manufacturing Corporation Ltd. Xiangtan 411101 China

An integrated monitoring system for running parameters of key mining equipmenton the basis of condition monitoring technology and modern communication networktechnology was *** system consists of a client computer with functions ofsignal acquisition and processing, and a host computer in the central control *** acquisition module of the client computer can collect the running parameters fromvarious monitoring terminals in *** DSP high-speed data processing system ofthe main control module can quickly achieve the numerical calculation for the *** signal modulation and signal demodulation are completed by the frequencyshift keying circuit and phase-locked loop frequency circuit, ***, the signalis sent to the host computer for logic estimation and diagnostic analysis using the networkcommunication technology, which is helpful for technicians and managers to control therunning state of equipment.

关键词：综合监测系统状态监测技术运行参数关键参数采矿设备基础计算机采集通信网络技术

Mapping the elastic properties of two-dimensional MoS_(2) via bimodal atomic force microscopy and finite element simulation

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npj Computational Materials 2018年第1期4卷 246-253页

作者： Yuhao Li Chuanbin Yu Yingye Gan Peng Jiang Junxi Yu Yun Ou Dai-Feng Zou Cheng Huang Jiahong Wang Tingting Jia Qian Luo Xue-Feng Yu Huijuan Zhao Cun-Fa Gao Jiangyu Li State key laboratory of Mechanics and Control of mechanical Structures Nanjing University of Aeronautics&AstronauticsNanjing 210016 JiangsuChina Shenzhen key laboratory of Nanobiomechanics Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen518055 GuangdongChina Department of mechanical Engineering Clemson UniversityClemsonSC 29634-0921USA key laboratory of Low Dimensional Materials and Application Technology of Ministry of Education School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105 HunanChina hunan Provincial key laboratory of health maintenance for mechanical equipment Hunan University of Science and TechnologyXiangtan 411201 HunanChina School of Physics and Electronic Science Hunan University of Science and TechnologyXiangtan 411201 HunanChina Institute of Biomedicine and Biotechnology Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055 GuangdongChina Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055 GuangdongChina Department of mechanical Engineering University of WashingtonSeattleWA 98195USA

Elasticity is a fundamental mechanical property of two-dimensional(2D)materials,and is critical for their application as well as for strain ***,accurate measurement of the elastic modulus of 2D materials remains a challenge,and the conventional suspension method suffers from a number of *** this work,we demonstrate a method to map the in-plane Young’s modulus of mono-and bi-layer MoS_(2) on a substrate with high spatial *** atomic force microscopy is used to accurately map the effective spring constant between the microscope tip and sample,and a finite element method is developed to quantitatively account for the effect of substrate stiffness on *** these methods,the in-plane Young’s modulus of monolayer MoS_(2) can be decoupled from the substrate and determined as 265±13 GPa,broadly consistent with previous reports though with substantially smaller *** is also found that the elasticity of mono-and bi-layer MoS_(2) cannot be differentiated,which is confirmed by the first principles *** method provides a convenient,robust and accurate means to map the in-plane Young’s modulus of 2D materials on a substrate.

关键词： modulus modal element