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Structural damage detection via adaptive dictionary learning and sparse representation of measured acceleration responses

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MEASUREMENT 2018年 128卷 377-387页

作者： Chen, Zepeng Pan, Chudong Yu, Ling Jinan Univ Sch Mech & Construct Engn Guangzhou 510632 Guangdong Peoples R China Jinan Univ MOE Key Lab Disaster Forecast & Control Engn Guangzhou 510632 Guangdong Peoples R China

Extracting damage-sensitive features from measured acceleration responses is still a big challenge in structural damage detection (SDD). In order to obtain the sparse representation of acceleration responses for damage identification, two dictionary learning methods and a damage indicator based on the change in mean sparsity (CMS) have been proposed in this paper. The first dictionary is empirical mode decomposition (EMD)-based dictionary generated by collecting a series of intrinsic mode functions (IMFs) while the second one is sparse coding (SC)-based dictionary learned by adaptively iterative optimization. The CMS is based on variation of a sparse features set. Numerical simulations on a simply-supported beam and on a 31-bar planar truss under different damage severities illustrate the effectiveness of the proposed methods for sparse representation and the capabilities of the defined CMS for damage indication. Comparative studies show that the SC-based dictionary outperforms the EMD-based dictionary in sparse representation. Moreover, a series of SDD experimental verifications on a simply-supported beam with a rectangular section in laboratory provide a further support to the proposed methods potentially using in-site acceleration measurements.

关键词： Structural damage detection (SDD) Sparse representation Empirical mode decomposition (EMD) Sparse coding (SC) Damage indicator

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A new structural damage detection strategy of hybrid PSO with Monte Carlo simulations and experimental verifications

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MEASUREMENT 2018年 122卷 658-669页

作者： Chen, Zepeng Yu, Ling Jinan Univ Sch Mech & Construct Engn Guangzhou 510632 Guangdong Peoples R China Jinan Univ MOE Key Lab Disaster Forecast & Control Engn Guangzhou 510632 Guangdong Peoples R China

Structural damage detection (SDD) is originally an optimization problem by minimizing discrepancy between measured and calculated data of structures. In most cases, natural frequencies and mode shapes are selected to define objective functions for SDD. In this study, a new SDD strategy of hybrid particle swarm optimization (HPSO) is proposed and its availability solution to SDD is studied via Monte Carlo simulations. First of all, PSO algorithms with different parameters are tested via Monte Carlo simulations to decide which combination of parameters is more beneficial for SDD. After that, a powerful local searching Nelder-Mead algorithm is embedded into the PSO with a new strategy, which confirms helpful to enhance the PSO global searching ability numerically and experimentally. Simply-supported beams with 10 and 20 finite elements are simulated respectively which prove our proposed method to be effective in SDD. Further, a series of experiments of a box-section steel beam are designed and fabricated in laboratory. Structural frequencies and mode shapes are measured under different crack damage patterns. The experimental verifications confirm the applicability of the proposed new SDD strategy. The SDD results of the experimental beam also show the outperformance of the proposed new SDD strategy. Some relative discussions are also described in detail.

关键词： Structural health monitoring Structural damage detection (SDD) Hybrid particle swarm optimization (HPSO) Monte Carlo simulations Experimental verifications

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Application of Matlab to Data Processing of Buckling Experiments

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IOP Conference Series: Materials Science and engineering 2020年第1期746卷

作者： Jiahui Zhou Peng Yang Jie Sun Chenyu Shi Jianghong Xue School of Mechanics and Construction Engineering Jinan University Key Lab of Disaster Forecast and Control in Engineering Ministry of Education Guangzhou 510632 Guangdong China

In this paper, matlab programs were written to efficiently process the experiment data for buckling and post-buckling of delaminated composite beams. In the experiments, data collected from 810 Material Test System (MTS) and from dial indicator were sampled at different frequencies, thus were not matched with each other in time. To solve this problem matlab programs were developed. It shows that using the developed program, the experiment data from the two testing systems are corresponding and truly reflect the changes of mechanical parameters in the buckling and post-buckling process of specimens in the experiments.

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On the Sensitivity of the Precipitation Partitioning Into Evapotranspiration and Runoff in Land Surface Parameterizations

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WATER RESOURCES RESEARCH 2019年第1期55卷 95-111页

作者： Zheng, Hui Yang, Zong-Liang Lin, Peirong Wei, Jiangfeng Wu, Wen-Ying Li, Lingcheng Zhao, Long Wang, Shu Chinese Acad Sci Inst Atmospher Phys CAS Key Lab Reg Climate Environm Res Temperate Ea Beijing Peoples R China Univ Texas Austin Dept Geol Sci John A & Katherine G Jackson Sch Geosci Austin TX 78712 USA Nanjing Univ Informat Sci & Technol Int Joint Res Lab Climate & Environm Change Collaborat Innovat Ctr Forecast & Evaluat Meteoro Key Lab Meteorol DisasterMinist Educ Nanjing Jiangsu Peoples R China Southwest Univ Sch Geog Sci Chongqing Peoples R China China Elect Power Res Inst State Key Lab Operat & Control Renewable Energy & Beijing Peoples R China

The precipitation partitioning between evapotranspiration (ET) and runoff (R) at the land surface is controlled by atmospheric boundary layer and terrestrial hydrological processes. These processes in land surface models are manifested primarily as stomatal conductance, soil moisture limitation factor to transpiration (-factor), turbulence, and runoff generation. What are the sensitivities of precipitation partitioning to the parameterizations of these processes? To address this overarching question, the annual and seasonal means of ET and R over the conterminous United States were simulated using 48 configurations of the Noah land surface model with multiparameterization options (Noah-MP). The Sobol' total sensitive index was used to quantify the sensitivity of ET and R to the parameterizations of the four processes mentioned above. Results show that the sensitivities of the annual means depend on climatic conditions and the interplay between ET and R plays an important role. In humid regions, precipitation is mostly partitioned into R, whereas the simulations can be more sensitive to ET's parameterizations. In arid regions, ET accounts for the major partition, whereas the simulations can be more sensitive to the runoff parameterization. Seasonal means exhibit different sensitivities from the annual means. The seasonal mean ET is more sensitive to ET's parameterizations, and R is more sensitive to the runoff parameterization. The -factor, which is neglectable for the annual means, is important for summer-time ET. Mediated by the terrestrial water storage memories, ET interplays R across seasons. The winter-time R is still sensitive to the stomatal conductance that only modulates growing-season ET.

关键词： evapotranspiration runoff parameterization sensitivity Noah-MP

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A Wideband Folded Reflectarray Antenna Based on Single-Layered Polarization Rotating Metasurface

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IEEE ACCESS 2020年 8卷 158579-158584页

作者： Su, Wei Luo, Wenhao Nie, Zhenhua Liu, Wen-Wen Cao, Zhen-Hua Wang, Zhi MOE Key Lab Disaster Forecast & Control Engn Guangzhou 510632 Peoples R China China Elect Prod Reliabil & Environm Testing Reli Sci & Technol Reliabil Phys & Applicat Technol El Guangzhou 510610 Peoples R China Jinan Univ Sch Mech & Construct Engn Guangzhou 510632 Peoples R China Zhengzhou Univ Sch Mech & Safety Engn Zhengzhou 450001 Peoples R China

A wideband folded reflectarray antenna (FRA) based on single-layered polarization rotating metasurface (PRM) is proposed. The FRA is composed of a wideband polarization grid (PG), a wideband PRM and a wideband circular waveguide as the primary source. First, a wideband polarization rotating unit cell consisting of rhombus-shaped metal patch etched on dielectric substrate is designed, which can be used to rotate polarization of the reflective wave 90 degrees relative to that of the incident wave. The element and its mirror image can provide 0 degrees, 90 degrees, 180 degrees and 270 degrees phase shifts with 2-bit phase quantization and relatively higher polarization conversion rates in the Ku band. Due to the introduction of PG and PRM, the distance between the PG surface and the feed phase center can be reduced to about 1/2 of the distance between the imaginary feed and PRM reflectarray. Finally, a wideband FRA consisting of 315 elements with circular aperture is designed, fabricated and measured. The measured results indicate that the proposed antenna achieves 39.5% 3-dB gain bandwidth with 25.5 dBi peak gain at 15 GHz. Its maximum aperture efficiency is about 40%. Low-profile and wideband features of the FRA make it be a candidate in the wireless communication systems.

关键词： Feeds Reflector antennas Antenna arrays Wideband Substrates Metals Apertures Folded reflectarray polarization rotating reflection surface (PRRS) polarization grid

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Visualization Analysis of Markov Chain Based on CiteSpace 2019

Visualization Analysis of Markov Chain Based on CiteSpace

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Proceedings of the 2019 11th International Conference on Information Management and engineering

作者： Songping Yang Ranni Zhang Yongyi Chen Fan Yang He Wang Ru Zhang Packaging Engineering Institute Jinan University and MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University Zhuhai China School of Marxism Jinan University Zhuhai China School of Intelligent Science and Engineering Jinan University Zhuhai China Electrical Engineering Institute Jinan University Zhuhai China School of Electrical Engineering Jinan University Zhuhai China International Business School Jinan University Zhuhai China

ISBN: (纸本)9781450372343

Since markov chain is widely used in various fields, the relevant literatures of markov chain theories are analyzed base on CiteSpace in this paper, adopting 10,000 literatures in CNKI and 10,000 literatures in WOS as datas. The relationship among markov chain, monte carlo integral and bayesian theory is analyzed primarily. What's more, the hidden markov model, markov random field, markov decision process and grey-markov model derived from markov chain are investigated emphatically. Ultimately, we reviews the development history of markov chain, makes a visual analysis of the authors, sorts out the research status of markov chain, and makes a comprehensive review of the application of markov chain.

关键词： Citespace Monte Carlo Visualization

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A modified first order shear deformation theory for Reissner-Mindlin composite panels with internal delamination

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COMPOSITE STRUCTURES 2019年 224卷 110935-000页

作者： Xia, Fei Jian, Fang Zhu, Zhipeng Li, Ping Liang, Haofeng Jin, Fusong Xue, Jianghong Jinan Univ Inst Appl Mechan Sch Mech & Construct Engn Guangzhou Guangdong Peoples R China Minist Educ Key Lab Disaster Forecast & Control Engn Guangzhou 510632 Guangdong Peoples R China

In this paper, an extended first order shear deformation theory is proposed for Reissner-Mindlin laminated composite panels with internal delamination. The distinctive feature of the present theory is that a contact mechanism is involved in the governing equations based on FSDT by introducing a constitutive relation between the contact force and the transverse deflection and are expressed in terms of the displacements and the rotation functions. The proposed theory is applied to investigate the structural failure of a delaminated Reissner-Mindlin composite panel subjected to in-plane compression. Numerical solutions are computed by developing MATlab program for different values of thickness-to-width ratio, material properties, aspect ratio and delamination conditions and are compared with those obtained from the modified classic laminated plate theory established in previous works and with ABAQUS results. Both theories and ABAQUS analysis predict a consistent global buckling mode without opening in between the delamination. The comparisons of the two solutions not only validate the efficiency and accuracy of the proposed M-FSDT but also evidence that neglecting the transverse shear strain may lead to the overestimation of the load capacity of the panel up to more than 35% when the thickness-to-width ratio is greater than 0.15.

关键词： Reissner-Mindlin plates Delamination Contact effect First order shear deformation Buckling

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A novel narrow surface cage for full endoscopic oblique lateral lumbar interbody fusion: A finite element study

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JOURNAL OF ORTHOPAEDIC SCIENCE 2019年第6期24卷 991-998页

作者： Ling, Qinjie He, Erxing Zhang, Huanliang Lin, Hui Huang, Wenhua Southern Med Univ Sch Basic Med Sci Guangdong Prov Key Lab Med Biomech 1023 South Shatai Rd Guangzhou 510515 Guangdong Peoples R China Guangzhou Med Univ Affiliated Hosp 1 Dept Spinal Surg 151 Yanjiang West Rd Guangzhou 510120 Guangdong Peoples R China Jinan Univ Inst Appl Mech MOE Key Lab Disaster Forecast & Control Engn Guangzhou 510632 Guangdong Peoples R China Putian Univ Sch Mech & Elect Engn Putian Fujian Peoples R China

Objective: To evaluate the mechanical response of a narrow surface cage that we designed for full endoscopic oblique lateral lumbar interbody fusion (FE-OL-LIF). Methods: A finite element (FE) model of lumbar spine was developed and validated. To simulate the FE-OL-LIF, the functional spinal unit (FSU) L4-L5 was assembled with a narrow surface polyetheretherketone (PEEK) cage, two rods and four screws. 500N load combined with 7.5Nm moment was applied to the surgical models. Effect of the cage width on the stress was studied. Results: Range of motion (ROM) in the surgical models significantly decreased by 88% in flexion, 91% extension, 85% in right and left lateral bending, 75% in right and left axial rotation as compared to the intact model. Width of the cage slightly decreased the ROM in all loading scenarios. Flexion produced the highest stress in the cages and endplates. In all loading cases, the maximum stresses of cages and endplates were both lower than their yield stress. Conclusions: In engineering analysis, the novel narrow-surface cage had a strength to support spine activities. 9 mm width cage was recommended in FE-OL-LIF. This study provided engineering evidence and technical advice to improve the design of minimally invasive cage. Fatigue test and cadaver trial shall be improved. (c) 2019 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

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Visualization analysis of Markov chain based on citespace 11

Visualization analysis of Markov chain based on citespace

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11th International Conference on Information Management and engineering, ICIME 2019

作者： Yang, Songping Chen, Yongyi Wang, He Zhang, Ranni Yang, Fan Zhang, Ru Packaging Engineering Institute Jinan University MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University Zhuhai China School of Intelligent Science and Engineering Jinan University Zhuhai China School of Electrical Engineering Jinan University Zhuhai China School of Marxism Jinan University Zhuhai China Electrical Engineering Institute Jinan University Zhuhai China International Business School Jinan University Zhuhai China

ISBN: (纸本)9781450372343

关键词： Visualization

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Application of Methods of Artificial Intelligence in Systems for Continuous Automatic Monitoring of Dust Concentration and Deposits in Mine Atmosphere

arXiv

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arXiv 2024年

作者： Trubicina, Daria Varnavskiy, Kirill Ermakov, Alexander Nepsha, Fedor Kozlov, Roman Golsanami, Naser Zhironkin, Sergey Mining Industry Digital Transformation Lab Mining Institute T.F. Gorbachev Kuzbass State Technical University 28 Vesennya st. Kemerovo650000 Russia Gorniy-TSOT" Ltd Sosoniy bulvar 1 Kemerovo650002 Russia Department of Theoretical Electrical Engineering and Electrification of Oil and Gas Industry Gubkin University Moscow119991 Russia State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province The Ministry of Science and Technology Shandong University of Science and Technology Qingdao266590 China Institute of Trade and Economy Siberian Federal University 79 Svobodny av. Krasnoyarsk660041 Russia Department of Open Pit Mining T.F. Gorbachev Kuzbass State Technical University 28 Vesennya st. Kemerovo650000 Russia

With the growth of coal production, the load on the production capacity of coal enterprises also increases, which leads to a concomitant increase in dust formation in both opencast and underground methods of mining coal deposits. Dust, generated during drilling, blasting operations, excavation, loading, crushing and transportation of mined rock is one of the factors that has a negative impact on the health of mining workers and on the level of environmental pollution with solid particles. Thus, increasing the efficiency of controlling the concentration of solid particles in the mine atmosphere and dust deposits is an urgent scientific and technical task. In doing so, the use of modern digital technologies within the framework of the industry 4.0 concept makes it possible to develop approaches that can significantly improve the quality of monitoring the state of the mine atmosphere at coal mining enterprises. This article provides a theoretical basis and test results for a system for continuous automatic monitoring of dust concentration in a mine atmosphere as the component of the multifunctional coal mine safety system. It is shown that monitoring the state of mine workings aerological safety can be carried out in real time through the system of the new generation using artificial intelligence. The ability of the proposed system to measure basic physical parameters affecting dust deposition (disperse composition, air humidity, dust concentration and air flow velocity) is noted. © 2024, CC BY.

关键词： Accident prevention

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