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Thermal-Structural Coupling Analysis of PCBA System

IOP Conference Series: Materials Science and Engineering 2018年第2期452卷

作者： Wei Su Junhua Zhu Renhuai Liu Zhiyuan He Scienceand Technology on Reliability Physics and Application Technology of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou China MOE Key Lab of Disaster Forecast and Control in Engineering Jinan University Guangzhou China Department of Mechanics and Civil Engineering Jinan University Guangzhou China

In this paper, the thermal and structural analysis of the PCBA system is provided by using the 3-D ANSYS package. The results of thermal and structural analysis for complex and simple model are compared. The paper also describes the deformation analysis of the PCBA system components, and the weak components sensitive to thermal stress are determined though thermal-structual analysis. The results of thermal analysis are helpful to the optimizing overall arrangement design of PCBA system.

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Detection of Rail Squats Based on Hilbert-Huang Transform by Using Bogie Acceleration Measurement

Detection of Rail Squats Based on Hilbert-Huang Transform by...

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第28届中国控制与决策会议

作者： Xiukun Wei Yuxin Liu Xianxian Yin State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Shanghai Key Laboratory of Computer Software Evaluating & Testing(Shanghai Development Center of Computer Software Technology)

ISBN: (纸本)9781467397155

The squat is a type of rolling contact fatigue(RCF) damage,the existence of squats directly impacts the operating condition of urban rail *** current detection methods of the rail squats damage are mainly based on track inspection car and rail flaw *** has some disadvantages,for example,long detection cycle,no real-time detecting and narrow scope,time consuming and *** this paper,a new detection method of squats which based on the in-service vehicles is *** bogie acceleration signal is used to detect the squats on the *** validate the possibility of the proposed *** the help of SIMPACK software,an in-service vehicle-track dynamic model and models of typical squats are built to generate the simulated bogie acceleration signals when the train wheels rolls over the *** simulation signals from the normal rail and the rail with squats are studied by HHT,it is found that0～50Hz and 300 Hz are the feature frequency caused by the squats damages.A unique W-shaped natural vibration mode is decomposed from the acceleration signals which is the feature vibration mode of the squat ***,the above detection method is applied to the field test data of Shanghai metro line *** feasibility and reliability of the proposed method are *** proposed method provides an alternative for real application.

关键词： Squats In Service Vehicle Acceleration Signals SIMPACK HHT Field Test

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Distributed Containment control for Multiple-agent Systems in Nonlinear Pure-feedback form via singular perturbation analysis

Distributed Containment Control for Multiple-agent Systems i...

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第28届中国控制与决策会议

作者： Hailiaing Zhou Yuehui Ji Shun Gao Yong Ran Yunxia Guo Tianjin Institute of Metrological Supervision and Testing(TIMST) School of Electrical Engineering and Tianjin Key Laboratory for Control Theory & Applications in Complicated SystemsTianjin University of Technology

ISBN: (纸本)9781467397155

The paper considers the distributed containment control problem of nonlinear multi-agent systems in pure-feedback form under switching directed communication topologies.A singular-perturbation-based command filtered back-stepping technology is addressed to design containment controller,while overcoming the "circular construction problem" in non-affine pure-feedback systems.A anti-tangent filter is proposed to estimate the virtual control and avoid the analytical deduction inherent in traditional back-stepping *** stability analysis is completed via the singular perturbation theory,revealing some novel features of the underlying *** distributed containment control can guarantee followers' outputs converge to the convex hull spanned by multiple dynamic leaders,and the containment tracking errors between leaders and followers in the overall closed-loop system is semi-global practical exponential ***,a simulation example is provided to illustrate the effectiveness of the control technology.

关键词： Distributed Containment control Nonlinear Multi-agent Systems Switching Topology Pure-feedback System Command Filtered control Singular Perturbation Analysis

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On-line measurement of surface temperature based on an infrared target 21

On-line measurement of surface temperature based on an infra...

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21st IMEKO World Congress on Measurement in Research and Industry

作者： Chen, Le Wang, Zeyao Fu, Yaqiong Wu, Yunxia Xu, Jianbin Zhejiang Provincial Key Laboratory of On-line Testing Equipment Calibration Technology Research China Jiliang University Hangzhou China

Infrared thermal imager is increasingly used in different fields in production and life, as it possesses the advantages of quick response and non-contact. However, the accuracy of temperature measured by infrared thermal imager is affected seriously by surface emissivity, which limits the use of infrared thermal imager. This paper proposes an on-line measurement of surface temperature by infrared thermal imager based on an infrared target. The experimental results show that the proposed method reduces the error of temperature measurement to about 2%.

关键词： Temperature measurement

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Fracture failure analysis of Fiber Reinforced Composites T-joints

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IOP Conference Series: Materials Science and Engineering 2017年第1期207卷

作者： Wei Su De-zhi Kong Ren-huai Liu Shi-qing Huang Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou China MOE Key Lab of Disaster Forecast and Control in Engineering Jinan University Guangzhou China Department of Mechanics and Civil Engineering Jinan University Guangzhou China

This paper discusses staple FRP T-joints on the project based on the classical beam theory of Euler-Bernoulli and a theoretical model of energy release rate is set up to discuss fracture propagation of composite T-joints. The paper is further analysis on fracture failure affected by composite pane depth and joints chamfer dimension parameters and so on. The conclusion benefit for extensive use of projects is also summarized.

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Mechanical Deformation Mechanism of Fiber Reinforced Composites T-joints

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IOP Conference Series: Materials Science and Engineering 2017年第1期207卷

作者： Wei Su Ke-qiang Cheng Ren-huai Liu Shi-qing Huang Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou China MOE Key Lab of Disaster Forecast and Control in Engineering Jinan University Guangzhou China Department of Mechanics and Civil Engineering Jinan University Guangzhou China

In this paper, we focus on the need for ideal theory analytical solution of mechanical deformation mechanism for T-joints. Through removing unnecessary constraints, stress equivalence system of T-joints can be established by force method. Solution equations of unknown nodal forces and the total vertical displacement can also be obtained, and this result can be used to evaluate strength of FRC T-joints.

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Surface Defects Detection of Railway Turnouts

Surface Defects Detection of Railway Turnouts

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第三十四届中国控制会议

作者： Li Shen Xiukun Wei Limin Jia State Key Laboratory of Railway Traffic Control and Safety Beijing Jiaotong University Shanghai Key Laboratory of Computer Software Evaluating & Testing(Shanghai Development Center of Computer Software Technology)

ISBN: (纸本)9781467374439

As the turnout is a critical part of railway tracks, its surface defects are directly related to the operation safety. The defects detection of turnout is an effect way to ensure the safety and comfort of urban transit railway. In this paper, the feature extraction of the turnout defects is investigated based on the bogie acceleration measurements. The normal turnout model and faulty turnout model based on SIMPACK are established first, from which the vehicle vibration acceleration is obtained. Then, the acceleration signal is analyzed in time- frequency domain. The results show that the power spectral density(PSD) and all the frequency-domain features are useful for detecting the poor fit defect of the switch point. And the peak and PSD features can be used to detect the curve opposite super-elevation. The proposed method provides alternative for the detection of turnout defects by using in-service vehicle.

关键词： turnout,defects feature,poor fit of switch point,curve opposite super-elevation

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Detection of Railway Track Squats by Using Bogie Acceleration Measurement

Detection of Railway Track Squats by Using Bogie Acceleratio...

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第三十四届中国控制会议

作者： Xianxian Yin Xiukun Wei Limin Jia State Key Laboratory of Railway Traffic Control and Safety Beijing Jiaotong University Shanghai Key Laboratory of Computer Software Evaluating & Testing(Shanghai Development Center of Computer Software Technology)

ISBN: (纸本)9781467374439

The railway track squat is one of the most dangerous track defects, it causes large dynamic contact force at the wheel-rail interface, leading to fast deterioration of the track, bring significant harm to the safety of the passengers. Early detection of such defects is very important for timely maintenance. In this paper, a squats detection method based on bogie acceleration(BA) measurement is presented. A simulation model with acceleration sensors is set up in the SIMPACK simulation environment. Time-frequency analysis and wavelet packet decomposition are applied to analyze these BA data obtained from the simulation model. The effectiveness of the above approach is demonstrated by simulation results.

关键词： squats BA measurement time-frequency domain analysis wavelet packet decomposition

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Characterization of PM and Microclimate in a Shanghai Subway Tunnel, China

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Procedia Engineering 2015年 102卷 1226-1232页

作者： Ting Qiao Guangli Xiu Yi Zheng Jun Yang Lina Wang State Environmental Protection Key Laboratory of Risk Assessment and Control on Chemical Process East China University of Science & Technology Shanghai 200237 China Technical Center of Shanghai Shentong Metro Group Co. Ltd. Shanghai 201103 China Shanghai An-He Environmental Testing Technique Co. Ltd. Shanghai 201611 China

A real-time monitoring campaign was conducted from November 11 th to November 15 th , 2013 in a Shanghai subway tunnel, consisting of temperature (T), relative humidity (RH) and PM 1 , PM 2.5 and PM 10 . The objective was to characterize PM and microclimate in the subway tunnel. Results indicated that median values of T, RH, PM 1 , PM 2.5 and PM 10 were 29.4°C, 29.6%, 42 μg/m 3 , 46 μg/m 3 and 58 μg/m 3 , respectively. Air quality in the tunnel was comparatively good, with 76% of PM 2.5 and 91% of PM 10 reaching relative standards. Independent samples t-test verified that PM 1 , PM 2.5 and PM 10 presented significant statistical differences between peak hours and off-peak hours (p<0.05). Notable weekly variation emerged during monitoring periods, which of all particles was as following: Friday > Thursday > Monday, Tuesday > Wednesday. Ratios of PM 1 /PM 10 and PM 2.5 /PM 10 were 0.49–1.00 and 0.56–1.00, respectively, which were high in outage and low in operation of trains. This phenomenon might result from plenty of coarse particles generated by mechanical grinding in the process of train driving.

关键词： Subway Tunnel Microclimate PM 1 PM 2.5 PM 10

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Analysis of noise of gear transmission system and control

Analysis of noise of gear transmission system and control

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作者： Zhang, Zhong Gang Fang, Bin Li, Xiao Qing School of Mechanical and Automotive Engineering Qilu University of Technology Jinan Shandong 250300 China Key Laboratory of Shandong High School Advanced Manufacture and Testing Control China

ISBN: (纸本)9783038351221

In this paper, the noise of gear transmission system of the type, source and mechanism is summarized and analyzed. The method of noise control was put forward according to the mechanism of noise of gear system. Put forward reasonable Suggestions For gear type and material selection in the design of gear transmission system, the gear parameters, processing technology, cabinet design, gear train assembly, gear modification, the lubrication mode. For gear system optimization design has a certain guiding significance. © (2014) Trans Tech Publications, Switzerland.

关键词： Power transmission

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