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Sparse grey forecasting model learning and applications to fatigue life prediction of aircraft lap joint structures

ISA Transactions 2025年

作者： Yang, Lu Xu, Qiuhui Wei, Baolei Xie, Naiming Yuan, Shenfang College of Information Management Nanjing Agricultural University Nanjing China College of Economics and Management Nanjing University of Aeronautics and Astronautics Nanjing China Research Center of Structural Health Monitoring and Prognosis State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics Nanjing China School of Economics and Management Nanjing University of Science and Technology Nanjing China

A key challenge in the study of grey forecasting models is model structure discovery: converting measurement data into equations that are not only predictive, but provide a deeper understanding of the underlying dynamics inherent in the observations. The predominant approach relies on the cumulative sum operator, a knowledge-based technique that requires a well-characterized shape and extensive empirical experience. In this work, we propose a paradigm for data-driven modelling that simultaneously learns the structures of grey forecasting models and estimates the measurement noise at each observation. First, in the context of a state-space framework utilizing the integral representation of the grey model as a state equation, a candidate feature library is designed to explicitly depict the model equation, likely in a redundant form, and solved by sparse learning. Then, by combining signal-noise decomposition and time-stepping constraints, a regularized objective function is formulated to jointly learn model structure and noise. Next, large-scale simulations are designed to investigate the finite sample performance of the proposed method, including model structural identification accuracy, forecasting accuracy, and denoising capability. The results demonstrate high accuracy in model structure learning and robustness to measurement noise. Finally, we conduct fatigue testing on aircraft lap joints to collect crack propagation data. The proposed method is then applied to uncover dynamic patterns in the evolution of fatigue cracks and predict the remaining useful life of aircraft lap joint structures. © 2025 International Society of Automation

关键词： Knowledge acquisition

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Analytical Solutions of Cracks Emanating from an Elliptic Hole in an Infinite Plate under Tension

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Chinese Journal of Mechanical Engineering 2014年第5期27卷 1057-1063页

作者： LIU Shuhong DUAN Shijie Department of Engineering Mechanics Shijiazhuang Tiedao University The Key Laboratory for Health Monitoring and Control of Large Structures of Hebei Province Department of Adult Education Shijiazhuang Tiedao University

It is a common phenomenon that the cracks originating from a hole can cause structural damage in ***,the fracture mechanics studies of hole edge crack problems are not *** problem of an elliptical hole with two collinear edge cracks of unequal length in an infinite plate under uniform tension at infinity is *** on the complex variable method,the analytical solutions of stress functions and stress intensity factors are *** stress distribution along the axes and the edge of the elliptical hole is given *** numerical results show that there is obvious stress concentration near the hole and cracks,and the stresses tend to applied loads at distances far from the defect,which conform to Saint-Venant’s ***,the stress functions are proved to be *** special conditions,the present configuration becomes the Griffith crack,two symmetrical cracks emanating from an elliptical hole,two cracks of unequal length emanating from a circular hole,a crack at the edge of a circular hole,or a crack emanating from an elliptical *** with available results,stress intensity factors for these special shapes of ellipses and cracks show good *** stress intensity factor for two cracks of unequal length at the edge of an elliptical hole increases with the crack length and the major-to-minor axis ratio of the elliptical *** stress distribution in an infinite plate containing an elliptic hole with unsymmetrical cracks is given for the first time.

关键词： hole crack stress distribution stress intensity factor

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Experimental and numerical studies on the buoyancy-driven smoke movement in inclined short tunnel fires under natural ventilation

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Tunnelling and Underground Space Technology 2025年 163卷

作者： Guo, Qinghua Yan, Zhiguo Xi, Baoping Li, Xingli Zhang, Yao School of Safety and Emergency Management Engineering Taiyuan University of Science and Technology 66 Waliu Road Taiyuan030024 China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University 1239 Siping Road Shanghai200092 China College of Mining Engineering Taiyuan University of Technology 18 West Xin Kuangyuan Road Taiyuan030024 China Key Laboratory of Large Structure Health Monitoring and Control Shijiazhuang050043 China

The paper focuses on the smoke flow movement in inclined short tunnel fires. Small-scale tunnel fire tests and numerical simulations are implemented by considering the tunnel inclination, heat release rate (HRR), tunnel height and upward distance from fire source to upward opening. The comprehensive impacts of tunnel inclination, HRR and upward length on the smoke back-layering flow and the influencing mechanism are emphasized. It is found that as the upward distance and tunnel inclination increase, the back-layering length decreases, and at the meantime, the decrease rate is affected by the HRR. Specifically, under a certain tunnel inclination, as the upward distance increases, the back-layering length decreases faster as HRR becomes greater. Besides, as the tunnel inclination increases, the decrease rate of the back-layering length against the upward distance also becomes greater under a larger HRR. Meanwhile, it is found that when the fire is located near the upward opening, back-layering length becomes longer as HRR increases, however, the increase trend levels off as the tunnel becomes steeper. This leads to the results that the back-layering length may increase, level off and decrease with HRRs. Based on these findings, a prediction correlation for the back-layering length is established considering multi-factors (tunnel inclination, upward length, HRR and tunnel height). Furthermore, the verification is implemented by comparing the calculated back-layering length and test and numerical simulation results, showing an acceptable prediction. © 2025 Elsevier Ltd

关键词： Buoyancy

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Analysis of transverse thermal regime difference of high-speed railway roadbed in seasonally frozen regions 15

Analysis of transverse thermal regime difference of high-spe...

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15th International Conference of the International Association for Computer Methods and Advances in Geomechanics, IACMAG 2017

作者： Zhang, Yuzhi Wen, An Cheng, Boyuan Key Laboratory for Health Monitoring and Control of Large Structures in Hebei Province Shijiazhuang Tiedao University Shijiazhuang Hebei050043 China

The transverse thermal regime differences are widespread for high-speed railway roadbed in seasonally frozen regions. Based on the monitored data of four typical roadbed sections from Harbin-Dalian high-speed railway in seasonally frozen regions of China, the external influence and heat absorption of roadbed different parts are studied quantitatively through the comparisons of the temperature amplitude and average temperature, and then the characteristics of the frost penetration development are analyzed. The temperature variation laws of the coldest and hottest months with depth are also analyzed. On the basis of the above analysis, the influence factors and potential hazards of the transverse differences are discussed. It is stated that: the west shoulders are most influenced by the external environment. The coldest and warmest month temperatures at a certain depth are characterized by a spindle shape. The increase of the latitude and roadbed height may aggravate the transverse thermal regime difference. In addition, the roadbed transverse thermal difference may induce the uneven roadbed deformation, hence, the roadbed stability and the ride comfort of track structure maybe threated. Therefore, the relevant monitoring and deformation mechanics studies should be further reinforced. © 2017 15th International Conference of the International Association for Computer Methods and Advances in Geomechanics

关键词： Deformation

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Construction of stability monitoring and evaluation system for high-speed railway roadbed in cold regions 8

Construction of stability monitoring and evaluation system f...

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8th International Conference on Structural health monitoring of Intelligent Infrastructure, SHMII 2017

作者： Zhang, Yuzhi Sun, Baochen Zhao, Weigang Wen, An The Key Laboratory for Health Monitoring and Control of Large Structures in Hebei Province Shijiazhuang Tiedao University Shijiazhuang Hebei050043 China

ISBN: (纸本)9781925553055

Along with the development of economy, the high-graded transportation line project are extending towards the cold regions gradually. The high-speed railway (HSR) in cold regions requires extreme high stability, thus the rigorous enigineering demands challenge the roadbed stability severely. The construction of the automatic monitoring and evaluation system of the HSR roadbed in cold regions, to master the safety conditions in real time, will guarantee the safe operation of high-speed train strongly. Through the characteristics analysis of the HSR roadbed in cold regions, the monitoring indices, static deformation combined with dynamic responses, are determined. The layout plan of monitoring points, which integrates the transverse discontinuity with horizontal continuity, is put forward. On the basis of conquering the continous high-precision collection sensors and technology suitable for the severe environment in cold regions, the automatic continous monitoring system of the HSR roadbed is developed, and the evaluation method of roadbed stability based on the on-site data information mining and numerical model is built. The monitoring system and stability method have realized the continous monitoring and stability evaluation of the Harbin-Dalian HSR under the water-heat-load combined action. This will be conductive to provide the scientific support for the stability change mechanism, the operation and maintenance of the HSR roadbed in cold regions. © 2017 International Society for Structural health monitoring of Intelligent Infrastrucure. All rights reserved.

关键词： Railroads

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Effective concrete surface crack detection based on extreme learning machine 8

Effective concrete surface crack detection based on extreme ...

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8th International Conference on Structural health monitoring of Intelligent Infrastructure, SHMII 2017

作者： Wang, Baoxian Zhao, Weigang Zhang, Hao Wang, Xinmin Zhang, Guangyuan Structural Health Monitoring and Control Institute Shijiazhuang Tiedao University Shijiazhuang050043 China Key Laboratory for Health Monitoring and Control of Large Structures Shijiazhuang050043 China Collaborative Innovation Center of Large Infrastructure Disaster Prevention and Reduction of Hebei Province China

ISBN: (纸本)9781925553055

Concrete surface crack detection has been an important field for the safety of civil engineering structure. However, under the background of high-density data acquiring demand, the existing crack detecting methods could not obtain the favorable efficiency and capability. In this work, we present a novel concrete surface crack detector for efficiently dealing with the massive crack images. Specifically, discrete cosine transformation is firstly utilized to extract the frequency domain characteristics of concrete surface images. Then, with the calculated image frequency features, an emergent learning technique (i.e., Extreme Learning Machine) is exploited to find the optimal separate hyper-plane between the crack object and backgrounds. Experiments on the crack images from the railway ballast-less track slab validate the effectiveness of the proposed method. © 2017 International Society for Structural health monitoring of Intelligent Infrastrucure. All rights reserved.

关键词： Frequency domain analysis

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Effective intrusion detection for railway scene based on video analytics 8

Effective intrusion detection for railway scene based on vid...

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8th International Conference on Structural health monitoring of Intelligent Infrastructure, SHMII 2017

作者： Li, Y.D. Lin, Y.B. Zhang, C. Zhao, W.G. School of Electronic and Information Engineering North China University of Technology Beijing100041 China Key Laboratory for Health Monitoring and Control of Large Structures Shijiazhuang050043 China Institute of Structure Health Monitoring and Control Shijiazhuang Tiedao University Shijiazhuang050043 China

ISBN: (纸本)9781925553055

Intrusion detection for railway scene is the essential method to avoid railway accidents caused by the invasions of pedestrians, falling rocks, animals, etc. In this paper, an automatic computer-vision based scheme is proposed to detect abnormal events in the track area, and send pre-warning signals to the control center. First, background is estimated by Gaussian mixture models, and the targets are obtained from the difference image between foreground and background combining with threshold, morphological filtering and connected component labeling. Second, mean shift algorithm is used to track the invasive target. To improve the tracking robustness, Histogram of Oriented Gradient (HOG) is chosen as the feature space to establish the target model, which has strong discriminative ability and robustness over illumination variation and small distortion of object. Third, behavior analysis is conducted based on target trajectory to determine whether there exist abnormal events in the track area. If yes, alarm messages with high-definition pictures are sent to control center. The proposed method has been operated on K141 spot of Shuohuang railway. The practical running results show that the intrusion detection system is effective and robust in railway scene. © 2017 International Society for Structural health monitoring of Intelligent Infrastrucure. All rights reserved.

关键词： Intrusion detection

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Analysis of void-disease detection in ballastless track of high-speed railway based on directional filter 8

Analysis of void-disease detection in ballastless track of h...

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8th International Conference on Structural health monitoring of Intelligent Infrastructure, SHMII 2017

作者： Yang, Y. Zhao, W.G. Du, Y.L. Tian, X.S. School of Electrical and Electronic engineering Shijiazhuang Tiedao University Shijiazhuang China Key Laboratory for Health Monitoring and Control of Large Structures in Hebei Province Shijiazhuang Tiedao University Shijiazhuang China

ISBN: (纸本)9781925553055

Owing to the concealment of void disease in cement-asphalt (CA) mortar and the requirements for rapidness, ground penetrating radar (GPR) has a good application prospect in detecting disease on a high-speed railway. Track slab, the covering of the CA mortar layer, is a multi-layer reinforced concrete structure;strong reflection of reinforcement makes disease identification difficult. To solve this problem, directional models were established to study the feature difference of echoes between reinforcement and void disease, and a horizontal filter based on curvelet transform was proposed to identify the void disease in CA mortar. Finally, forward simulation was conducted to validate the performance of the presented algorithm. Results show that the horizontal filter method contributes to the identification of void diseases in the CA mortar layer which were located in the middle of the reinforcement group. This study promotes the application of GPR on disease detection in a high-speed railway. © 2017 International Society for Structural health monitoring of Intelligent Infrastrucure. All rights reserved.

关键词： Ground penetrating radar systems

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Damage evolution analysis of rock under Uniaxial compression and Brazilian splitting based on discrete element method 10

Damage evolution analysis of rock under Uniaxial compression...

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2020 10th Chinese Geosynthetics Conference and International Symposium on Civil Engineering and Geosynthetics, ISCEG 2020

作者： De-Kang, Li Hao-Ran, Li Meng, Liu Zi-Heng, Wang Zheng, Li Structural Health Monitoring and Control Institute Shijiazhuang Tiedao University Shijiazhuang Hebei050043 China Key Laboratory for Health Monitoring and Control of Large Structures Shijiazhuang Tiedao University Shijiazhuang Hebei050043 China Second Geological Team of Hebei Coalfield Geological Bureau Xingtai Hebei054001 China

In order to better analyze the mechanical behavior of rock in uniaxial compression and Brazilian splitting, numerical model was established according to laboratory test by PFC2D particle flow program, and the simulation results were compared with the experimental results. The results show that when the rock reaches the peak stress, the failure curve of cement appears an obvious turning point, and the failure rate of cement *** compressive strength of rock is much greater than the tensile strength under compression condition. The preloading method is more detailed for experimental restoration, and it provides certain reference significance for rock simulation in the future. © The Authors, published by EDP Sciences 2020.

关键词： Rocks

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On-line Updated Guided Wave-Based Gaussian Process Method for Damage Evaluation of Aircraft Structure 11

On-line Updated Guided Wave-Based Gaussian Process Method fo...

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11th European Workshop on Structural health monitoring, EWSHM 2024

作者： Tong, Lin Jing, Hutao Chen, Jian Yuan, Shenfang Wang, Hui Research Center of Structural Health Monitoring and Prognosis State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics Nanjing China

Accurate damage evaluation for an aircraft by using guided wave(GW) - based structural health monitoring (SHM) technology is in critical demand. An aircraft experiences various uncertainties during its service life, such as the time-varying environment, operational conditions, and different flight missions. Additionally, the actual aircraft structure involves complex structural forms such as varied thicknesses, stiffeners, and ribs, leading to a strong uncertainty of damage initiation and propagation. Consequently, when applied to an individual aircraft structure, the diagnosis model trained by prior data inevitably introduces errors, and the errors accumulate as the damage propagates, which brings challenges in engineering application. To achieve individual aircraft structure's more accurate damage evaluation, an on-line updated GW-based Gaussian process (GP) damage evaluation method is investigated in this paper. Multi-source data from the service and maintenance stages are utilized to continuously update and evolve the GP model, enabling its accurate evaluation throughout the long-term service life. © 2024 11th European Workshop on Structural health monitoring, EWSHM 2024. All rights reserved.

关键词： Gaussian distribution

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