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5th Academic Conference of Geology Resource Management and Sustainable Development

作者： Qi, Liming Qi, Ming Key Lab of Mine Disaster Prevention and Control in Hebei Province Langfang Hebei065201 China School of Safety Engineering North China Institute of Science and Technology Beijing10160 China

ISBN: (纸本)9781921712647

Gas layer soft coal mine gas extraction efficiency in China is low, the reason is because the surrounding drilling is fractured, led to the production of air leakage, so become the research focus of fracture. In this paper, a similar simulation experiment is carried out to drill holes of different water-bearing types of coal, and the distribution of fractures in the surrounding area is extracted and studied. The results showed that the water content of different type drilling, coal around fracture distributions have differences, but most of the crack length is less than 5 mm, and on this basis, the experimental analysis on the causes of differences. © 2017 Aussino Academic Publishing House (AAPH). All Rights Reserved.

关键词： Planning

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Investigation on mapping relationship between deflection and cable tension by artificial neural networks 11

Investigation on mapping relationship between deflection and...

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11th International Workshop on Structural Health Monitoring 2017: Real-Time Material State Awareness and Data-Driven Safety Assurance, IWSHM 2017

作者： Tian, Yadi Li, Hui Key Laboratory of Intelligent Disaster Prevention and Mitigation for Civil Infrastructure Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters Ministry of Industry and Information Technology Key Laboratory of Structural Dynamic Behavior and Control School of Civil Engineering Harbin Institute of Technology Harbin150090 China

ISBN: (纸本)9781605953304

Cables usually serve as critical load-bearing structural components in cable-stayed bridges. Vertical deflection is an important overall indicator that directly reflects the health status of bridge. The relationship between cable tension and vertical deflection also reflects the underlying mechanism of structures. In this context, a machine learning-based approach is proposed. Cable tension and vertical deflection are caused by prestress, temperature and vehicle loads. In this study, we focus on the cable force and vertical deflection caused by vehicle loads. Artificial neural network (ANN) is employed as the supervised learning method to learn the relationship between cable tension and vertical deflection. Field monitored data of Jintang Bridge are used to test the validity of the proposed method. The results show that ANN is capable of modelling vertical deflection from cable tension data in the case of arbitrary vehicle distribution. The proposed method which integrates the local and global variables by using two different kinds of monitoring data, avoids the complicated mechanical derivations, and is proved to be environment-insensitive.

关键词： Neural networks

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Analysis and Inverse Substructuring Computation on Dynamic Quality of Mechanical Assembly

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Chinese Journal of Mechanical engineering 2016年第3期29卷 539-548页

作者： Lü Guangqing YI Chuijie FANG Ke Key Lab of Disasters Forecast and Control in Engineering of Ministry of Education Jinan University Research Center of Equipment Energy & Environment Qingdao Technological University

Mechanical assembly has its own dynamic quality directly affecting the dynamic quality of whole product and should be considered in quality inspection and estimation of mechanical assembly. Based on functional relations between dynamic characteristics involved in mechanical assembly, the effects of assembling process on dynamic characteristics of substructural components of an assembly system are investigated by substructuring analysis. Assembly-coupling dynamic stiffness is clarified as the dominant factor of the effects and can be used as a quantitative measure of assembly dynamic quality. Two computational schemes using frequency response functions（FRFs） to determine the stiffness are provided and discussed by inverse substructuring analysis, including their applicable conditions and implementation procedure in application. Eigenvalue analysis on matrix-ratios of FRFs before and after assembling is employed and well validates the analytical outcomes and the schemes via both a lumped-parameter model and its analogic experimental counterpart. Applying the two schemes to inspect the dynamic quality provides the message of dynamic performance of the assembly system, and therefore improves conventional quality inspection and estimation of mechanical assembly in completeness.

关键词： mechanical assembly dynamic quality substructuring analysis inverse substructuring assembly-coupling dynamic stiffness

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Fracture failure analysis of Fiber Reinforced Composites T-joints 4

Fracture failure analysis of Fiber Reinforced Composites T-j...

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4th International Conference on Advanced Composite Materials and Manufacturing engineering (ACMME)

作者： Su, Wei Kong, De-zhi Liu, Ren-huai Huang, Shi-qing China Elect Prod Reliabil & Environm Testing Res Sci & Technol Reliabil Phys & Applicat Technol El Guangzhou Guangdong Peoples R China Jinan Univ Dept Mech & Civil Engn Guangzhou Guangdong Peoples R China Jinan Univ MOE Key Lab Disaster Forecast & Control Engn Guangzhou Guangdong Peoples R 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.

关键词： Fiber reinforced plastics

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Mechanical Deformation Mechanism of Fiber Reinforced Composites T-joints 4

Mechanical Deformation Mechanism of Fiber Reinforced Composi...

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4th International Conference on Advanced Composite Materials and Manufacturing engineering (ACMME)

作者： Su, Wei Cheng, Ke-qiang Liu, Ren-huai Huang, Shi-qing China Elect Prod Reliabil & Environm Testing Res Sci & Technol Reliabil Phys & Applicat Technol El Guangzhou Guangdong Peoples R China Jinan Univ Dept Mech & Civil Engn Guangzhou Guangdong Peoples R China Jinan Univ MOE Key Lab Disaster Forecast & Control Engn Guangzhou Guangdong Peoples R 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.

关键词： Deformation

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Heat and mortality for ischemic and hemorrhagic stroke in 12 cities of Jiangsu Province, China

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SCIENCE OF THE TOTAL ENVIRONMENT 2017年 601卷 271-277页

作者： Zhou, Lian Chen, Kai Chen, Xiaodong Jing, Yuanshu Ma, Zongwei Bi, Jun Kinney, Patrick L. Nanjing Univ Informat Sci & Technol Coll Appl Meteorol 219 Ningliu Rd Nanjing 210044 Jiangsu Peoples R China Jiangsu Prov Ctr Dis Prevent & Control Nanjing Jiangsu Peoples R China Nanjing Univ Sch Environm State Key Lab Pollut Control & Resource Reuse Nanjing Jiangsu Peoples R China Minist Educ Key Lab Meteorol Disaster Collaborat Innovat Ctr Forecast & Evaluat Meteoro Nanjing Jiangsu Peoples R China Jiangsu Collaborat Innovat Ctr Atmospher Environm Nanjing Jiangsu Peoples R China Boston Univ Sch Publ Hlth Dept Environm Hlth 715 Albany St Boston MA 02118 USA

Background: Little evidence exists on the relationship between heat and subtypes of stroke mortality, especially in China. Moreover, few studies have reported the effect modification by individual characteristics on heatrelated stroke mortality. In this study, we aimed to evaluate the effect of heat exposure on total, ischemic, and hemorrhagic stroke mortality and its individual modifiers in 12 cities in Jiangsu Province, China during 2009 to 2013. Methods: We first used a distributed lag non-linear model with quasi-Poisson regression to examine the cityspecific heat-related total, ischemic, and hemorrhagic stroke mortality risks at 99th percentile vs. 75th percentile of daily mean temperature in the whole year for each city, while adjusting for long-term trend, season, relative humidity, and day of the week. Then, we used a random-effects meta-analysis to pool the city-specific risk estimates. We also considered confounding by air pollution and effect modification by gender, age, education level, and death location. Results: Overall, the heat-relatedmortality risk in 12 Jiangsu cities was 1.54 (95% CI: 1.44 to 1.65) for total stroke, 1.63 (95% CI: 1.48 to 1.80) for ischemic stroke, and 1.36 (95% CI: 1.26 to 1.48) for hemorrhagic stroke, respectively. Estimated total, ischemic, and hemorrhagic strokemortality riskswere higher forwomen versus men, older people versus younger people, those with low education levels versus high education levels, and deaths that occurred outside of hospital. Air pollutants did not significantly influence the heat-related stroke mortality risk. Conclusions: Heat exposure significantly increased both ischemic and hemorrhagic strokemortality risks in Jiangsu Province, China. Females, the elderly, and those with low education levels are particularly vulnerable to this effect. (C) 2017 Elsevier B.V. All rights reserved.

关键词： Heat Ischemic stroke Hemorrhagic stroke Mortality Vulnerability

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LQD-RKHS-based distribution-to-distribution regression methodology for restoring the probability distributions of missing SHM data

arXiv

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arXiv 2018年

作者： Chen, Zhicheng Bao, Yuequan Li, Hui Spencer, Billie F. Key Lab of Intelligent Disaster Mitigation of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin China Key Lab of Structures Dynamic Behaviour and Control of the Ministry of Education Harbin Institute of Technology Harbin China School of Civil Engineering Harbin Institute of Technology Harbin China Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign UrbanaIL United States Department of Civil and Environmental Engineering University of Illinois at Urbana - Champaign UrbanaIL United States

Data loss is a critical problem in structural health monitoring (SHM). Probability distributions play a highly important role in many applications. Improving the quality of distribution estimations made using incomplete samples is highly important. Missing samples can be compensated for by applying conventional missing data restoration methods;however, ensuring that restored samples roughly follow underlying distributions of true missing data remains a challenge. Another strategy involves directly restoring the probability density function (PDF) for a sensor when samples are missing by leveraging distribution information from another sensor with complete data using distribution regression techniques;existing methods include the conventional distribution-to-distribution regression (DDR) and distribution-to-warping function regression (DWR) methods. Due to constraints on PDFs and warping functions, the regression functions of both methods are estimated from the Nadaraya-Watson kernel estimator with relatively low degrees of precision. This article proposes a new indirect distribution-to-distribution regression method in the context of functional data analysis for restoring distributions of missing SHM data. PDFs are transformed to ordinary functions residing in a Hilbert space via the newly proposed log-quantile-density (LQD) transformation;the regression for distributions is realized in the transformed space via a functional regression model constructed based on the theory of Reproducing Kernel Hilbert Space (RKHS), corresponding result is subsequently mapped back to the density space through the inverse LQD transformation. Test results using field monitoring data indicate that the new method significantly outperforms conventional methods in general cases;however, in extrapolation cases, the new method is inferior to the distribution-to-warping function regression method. Copyright © 2018, The Authors. All rights reserved.

关键词： Probability distributions

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A Simulation of Low and High Cycle Fatigue Failure Effects for Metal Matrix Composites Based on Innovative J₂-Flow Elastoplasticity Model

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MATERIALS 2017年第10期10卷 1126-1126页

作者： Wang, Zhaoling Xiao, Heng Weifang Univ Sch Math & Informat Sci Weifang 261061 Peoples R China Jinan Univ Sch Mech & Construct Engn MOE Key Lab Disaster Forecast & Control Engn Guangzhou 510632 Guangdong Peoples R China

New elastoplastic J(2)-flow constitutive equations at finite deformations are proposed for the purpose of simulating the fatigue failure behavior for metal matrix composites. A new, direct approach is established in a two-fold sense of unification. Namely, both low and high cycle fatigue failure effects of metal matrix composites may be simultaneously simulated for various cases of the weight percentage of reinforcing particles. Novel results are presented in four respects. First, both the yield condition and the loading-unloading conditions in a usual sense need not be involved but may be automatically incorporated into inherent features of the proposed constitutive equations;second, low-to-high cycle fatigue failure effects may be directly represented by a simple condition for asymptotic loss of the material strength, without involving any additional damage-like variables;third, both high and low cycle fatigue failure effects need not be separately treated but may be automatically derived as model predictions with a unified criterion for critical failure states, without assuming any ad hoc failure criteria;and, finally, explicit expressions for each incorporated model parameter changing with the weight percentage of reinforcing particles may be obtainable directly from appropriate test data. Numerical examples are presented for medium-to-high cycle fatigue failure effects and for complicated duplex effects from low to high cycle fatigue failure effects. Simulation results are in good agreement with experimental data.

关键词： metal matrix composites high and low cycle fatigue finite deformations new elastoplastic equations unified failure criterion direct simulation

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Data science and engineering for structural health monitoring 8

Data science and engineering for structural health monitorin...

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8th International Conference on Structural Health Monitoring of Intelligent Infrastructure, SHMII 2017

作者： Li, H. Bao, Y.Q. Li, S.L. Ou, J.P. Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin150090 China Key Lab of Intelligent Disaster Mitigation of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China School of Civil Engineering Harbin Institute of Technology Harbin150090 China

ISBN: (纸本)9781925553055

Structural health monitoring (SHM) technology study the damage or even characteristics of disaster evolving of structures by various types of sensors installed on structures and provide scientific support for the structural design, construction, maintenance and operation safety. The significant scientific issues of SHM can be concluded as 'sensing' and 'data'. According to the widely application of SHM on civil infrastructures and accumulation of huge quantities of data, it is well-recognized that data sciences and engineering for SHM is increasingly becoming a world-wide research focus. The issue of 'data' is core target of SHM which includes the data acquisition, transmission and management, data analysis and mining, structural damage identification and structural safety assessment and so on. This paper reviews the recent research development of data sciences and engineering on our research group which includes data acquisition by compressive sensing based on group sparse optimization, computer vison and deep learning methods for data anomaly detection and structure condition assessment, the identification and modeling of spatio-temporal distribution of vehicle loads, and corrosion damage and crack identification by computer vision ***, the artificial intelligence in civil engineering is the extension of SHM technique, and will make the civil structure have ability of "see", "sensing", "thinking","talking", "action and "adapation" (2S+2T+2A). © 2017 International Society for Structural Health Monitoring of Intelligent Infrastrucure. All rights reserved.

关键词： Structural health monitoring

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An on-site evaluation method for corrosion degradation of in-service cable wires by image histogram matching 11

An on-site evaluation method for corrosion degradation of in...

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11th International Workshop on Structural Health Monitoring 2017: Real-Time Material State Awareness and Data-Driven Safety Assurance, IWSHM 2017

作者： Xu, Yang Li, Shunlong Li, Hui Gu, Chenyu Li, Xinbin Chen, Xiaowei Qiao, Weidong Key Lab of Intelligent Disaster Mitigation Ministry of Industrial and Information Technology Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters Ministry of Industry and Information Technology Harbin150090 China Key Lab of Structures Dynamic Behavior and Control Ministry of Education Harbin150090 China School of Civil Engineering Harbin Institute of Technology Harbin150090 China School of Transportation Science and Engineering Harbin Institute of Technology Harbin150090 China

ISBN: (纸本)9781605953304

This paper proposes a novel non-destructive method by image histogram matching to evaluate the corrosion degradation of cable wires in service quantitatively. Artificial accelerated salt spray test is adopted to simulate the corrosion environment, and adequate RGB images are taken by a consumer-grade camera to cover the whole information of corroded surface for each specimen under different corrosion periods. Histogram distribution analysis is applied to study the concentrated modes of RGB images, and joint Gaussian distribution is fitted to capture location parameters. Timevariant models of the location parameters are regressed and then the mechanical properties are learnt by tensile and fatigue tests. Once the features of RGB corrosion images of steel wires are matched to the proposed time-variant models, the corresponding corrosion degree and mechanical properties can be estimated. The proposed method is meaningful for the on-site evaluation of cable wires in service with no need to carry on corrosion and mechanical degradation tests after replacing cables.

关键词： Graphic methods

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