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Probabilistic analysis of tunnel face seismic stability in layered rock masses using Polynomial Chaos Kriging metamodel

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2678-2693页

作者： jianhong man Tingting Zhang Hongwei Huang Daniel Dias Department of Geotechnical Engineering Key Laboratory of Geotechnical and Underground Engineering of Ministry of EducationCollege of Civil EngineeringTongji UniversityShanghai200092China Grenoble Alpes 3SR LabCNRS UMR 5521Grenoble38000France

Face stability is an essential issue in tunnel design and *** rock masses are typical and ubiquitous;uncertainties in rock properties always *** view of this,a comprehensive method,which combines the Upper bound Limit analysis of Tunnel face stability,the Polynomial Chaos Kriging,the Monte-Carlo Simulation and Analysis of Covariance method(ULT-PCK-MA),is proposed to investigate the seismic stability of tunnel faces.A two-dimensional analytical model of ULT is developed to evaluate the virtual support force based on the upper bound limit *** efficient probabilistic analysis method PCK-MA based on the adaptive Polynomial Chaos Kriging metamodel is then implemented to investigate the parameter uncertainty *** input parameters,including geological strength indices,uniaxial compressive strengths and constants for three rock formations,and the horizontal seismic coefficients,are treated as random *** effects of these parameter uncertainties on the failure probability and sensitivity indices are *** addition,the effects of weak layer position,the middle layer thickness and quality,the tunnel diameter,the parameters correlation,and the seismic loadings are investigated,*** results show that the layer distributions significantly influence the tunnel face probabilistic stability,particularly when the weak rock is present in the bottom *** efficiency of the proposed ULT-PCK-MA is validated,which is expected to facilitate the engineering design and construction.

关键词： Tunnel face stability Layered rock masses Polynomial Chaos Kriging(PCK) Sensitivity index Seismic loadings

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Anisotropy of multi-layered structure with sliding and bonded interlayer conditions

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 632-645页

作者： Lingyun YOU Kezhen YAN jianhong man Nengyuan LIU College of Civil Engineering Hunan UniversityChangsha 410082China Department of Civil and Environmental Engineering Michigan Technological UniversityHoughtonMI 49931USA

A better understanding of the mechanical behavior of the multilayered structure under extermal loading is the most important item for the structural design and the risk *** objective of this study are to propose and develop an analytical solution for the mechanical behaviors of multi-layered structure generated by axisy mmetric loading,and to investigate the impact of anisotropic layers and interlayer conditions on the multi-layered *** reach these objectives,first,according to the goveming equations,the analytical solution for a single layer was formulated by adopting the spatial Hankel *** the global matrix technique is applied to achieve the analytical solution of multi-layered structure in Hankel *** sliding and bonded interlayer conditions were considered in this ***,the numerical inversion of integral transform was used to solve the components of displacement and stress in real ***-Lcgendre quadrature is a key scheme in the numerical inversion ***,following by the verification of the proposed analytical solution,one typical three-layered flexible pavement was applied as the computing carrier of numerical analysis for the multi-layered *** results have shown that the anisotropic layers and the interlayer conditions significantly affect the mechanical behaviors of the proposed structure.

关键词： multi-layered structure Hankel transformation anisotropic transversely isotropic interlayer condition Gauss-Legendre quadrature

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Face stability analysis of circular tunnels in layered rock masses using the upper bound theorem

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1836-1871页

作者： jianhong man Mingliang Zhou Dongming Zhang Hongwei Huang Jiayao Chen Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai200092China

An analysis of tunnel face stability generally assumes a single homogeneous rock ***,most rock tunnel projects are excavated in stratified rock *** paper presents a two-dimensional(2D)analytical model for estimating the face stability of a rock tunnel in the presence of rock mass *** model uses the kinematical limit analysis approach combined with the block calculation technique.A virtual support force is applied to the tunnel face,and then solved using an optimization method based on the upper limit theorem of limit analysis and the nonlinear Hoek-Brown yield *** design charts are provided to analyze the effects of rock layer thickness on tunnel face stability,tunnel diameter,the arrangement sequence of weak and strong rock layers,and the variation in rock layer parameters at different *** results indicate that the thickness of the rock layer,tunnel diameter,and arrangement sequence of weak and strong rock layers significantly affect the tunnel face *** in the parameters of the lower layer of the tunnel face have a greater effect on tunnel stability than those of the upper layer.

关键词： Face stability Rock tunnel Layered rock masses Upper bound solution Hoek—Brown criterion

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A novel image-based approach for interactive characterization of rock fracture spacing in a tunnel face

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1077-1088页

作者： Jiayao Chen Yifeng Chen Anthony G.Cohn Hongwei Huang jianhong man Lijun Wei Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai200092China School of Computing University of LeedsLeedsLS29JTUK Department of Computer Science and Technology Tongji UniversityShanghai211985China School of Civil Engineering Shandong UniversityJinan250061China Luzhong Institute of Safety Environmental Protection Engineering and Materialsand School of Mechanical and Electrical EngineeringQingdao University of Science and TechnologyQingdao255000China

This paper presents a novel integrated method for interactive characterization of fracture spacing in rock tunnel *** main procedure includes four steps:(1)Automatic extraction of fracture traces,(2)digitization of trace maps,(3)disconnection and grouping of traces,and(4)interactive measurement of fracture set spacing,total spacing,and surface rock quality designation(S-RQD)*** evaluate the performance of the proposed method,sample images were obtained by employing a photogrammetrybased scheme in tunnel *** were then conducted to determine the optimal parameter values(*** threshold,angle threshold,and number of fracture trace grouping)for characterizing rock fracture *** applying the identified optimal parameters involved in the model,the proposed method could lead to excellent qualitative results to a new tunnel *** perform a quantitative analysis,three methods(***,straightening,and the proposed method)were employed in the same study and comparisons were *** proposed method agrees well with the field measurement in terms of the maximum and average values of measured spacing ***,the proposed method has reasonably good accuracy and interactive advantage for estimating the ultimate fracture spacing and *** can be a possible extension of existing methods for fracture spacing characterization for two-dimensional(2D)rock tunnel faces.

关键词： Fracture spacing Rock tunnel Image processing Fracture set grouping

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考虑层间接触状态的横观各向同性结构动力响应解析解

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湖南大学学报（自然科学版） 2019年第11期46卷 97-105页

作者：颜可珍满建宏石挺魏陈帅刘能源湖南大学土木工程学院

基于线弹性体动力学基本方程,结合坐标变换、Buchwald势函数,建立了移动荷载作用下层状横观各向同性结构的动力控制方程,利用傅里叶变换及其微分性质得到了在Fourier变换域内单层有限厚度刚度矩阵和半空间无限体刚度矩阵.考虑层间接触... 详细信息

基于线弹性体动力学基本方程,结合坐标变换、Buchwald势函数,建立了移动荷载作用下层状横观各向同性结构的动力控制方程,利用傅里叶变换及其微分性质得到了在Fourier变换域内单层有限厚度刚度矩阵和半空间无限体刚度矩阵.考虑层间接触条件组装各刚度矩阵得到总刚度矩阵,并根据边界条件求解总刚度矩阵在变换域内的解.然后,进行Fourier逆变换将变换域内的解转化为物理域内的解.通过与已有文献结果的对比验证了本文理论推导的正确性,随后通过参数的变化来模拟层间接触状态的改变,并分析了面层与基层层间接触状态对路面结构动力响应的影响.计算结果表明:基、面层层间接触状况越差,路面结构的整体性耐久性越差.

关键词：层间接触横观各向同性层状结构移动荷载动力响应 Fourier变换

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恩格斯劳动思想的四重维度考察——兼论对新时代开展劳动教育的启示

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保山学院学报 2024年第4期43卷 1-8页

作者：黄建宏陈仕伟江西财经大学马克思主义学院江西南昌330013

恩格斯劳动思想是马克思主义理论的重要组成部分,恩格斯超越了对劳动的狭义界定,从辩证唯物主义和历史唯物主义出发对人类所特有的劳动进行了全面论述。他在“劳动创造了人本身”这一哲学命题中,深刻揭示劳动在从猿到人的转变、人的本... 详细信息

恩格斯劳动思想是马克思主义理论的重要组成部分,恩格斯超越了对劳动的狭义界定,从辩证唯物主义和历史唯物主义出发对人类所特有的劳动进行了全面论述。他在“劳动创造了人本身”这一哲学命题中,深刻揭示劳动在从猿到人的转变、人的本质的公开展示、实现人与自然的和谐共生以及促进社会发展中的核心作用。这为我们正确把握人类劳动发展、社会发展和人的自由而全面发展奠定了科学的理论基础。因此,深入研究恩格斯劳动思想,不仅有助于系统理解和准确把握马克思主义的唯物史观,而且对于我们在新时代开展劳动教育具有重要的启示意义。

关键词：恩格斯劳动思想新时代劳动教育启示

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Blood pressure,body mass index lowering and ketogenesis in Qigong Bigu

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Acta Epileptologica 2021年第1期3卷 172-178页

作者： Bin Hong Runqi Luo Dezhi Cao man Zhang Kewei Fang jianhong Guo Jianxiang Liao Bijie Second People’s Hospital Bijie 551700Guizhou ProvinceChina Shenzhen Children’s Hospital Shenzhen 518038Guangdong ProvinceChina School of Traditional Chinese Medicine Ningxia Medical UniversityYinchuan 750021Ningxia Hui Autonomous RegionChina

Background:Hypertension is one of the most common comorbid conditions of *** and epilepsy may be related to each *** Bigu practice induces a similar effect as fasting in the first *** ketogenesis is induced during ketogenic diet therapy,we hypothesize that ketogenesis is detectable and related body weight loss would occur during the first week of Qigong Bigu ***:During the prospective observational study,34 healthy adult participants attended the Qigong Bigu practice for one *** blood pressure,body weight,calorie consumption,blood glucose and beta-hydroxybutyrate level were ***:The body weight and body mass index decreased by 2.39±1.34 kg(95%CI 1.92–2.85)and 0.94±0.57(95%CI 0.73–1.15),respectively,after five days of practice(P<0.001).The systolic and diastolic blood pressure decreased by 17.86±14.17 mmHg(95%CI 12.36–23.35)and 9.75±7.45 mmHg(95%CI 6.86–12.64),respectively(P<0.001).The average five-day calorie consumption was 1197.47±569.97 kcal(95%CI 998.60–1396.35).Meanwhile,no symptomatic hypoglycemia or other significant side effects were *** blood beta-hydroxybutyrate level increased to a nutritional level of 1.15±1.12 mmol/L(95%CI 0.76–1.62).The calorie consumption negatively correlated to the beta-hydroxybutyrate level in the *** loss of body weight and the decrease of body mass index were positively correlated to the blood beta-hydroxybutyrate ***:Qigong Bigu can decrease the blood pressure,the body weight and the body mass index in healthy adult *** fasting stage of Qigong Bigu is accompanied by *** trial of Qigong Bigu in hypertension and epilepsy patients might be *** blood beta-hydroxybutyrate might be used as a biomarker to evaluate the effect of Qigong Bigu practice during fasting.

关键词： Blood pressure Body weight Body mass index Epilepsy Ketogenic diet Qigong Bigu Fasting Comorbidity Hypertension Pigu

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An electrical-filtered optical heterodyne technique for tuning speed measurement of DBR lasers

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Chinese Science Bulletin 2011年第7期56卷 704-708页

作者： JiangWei man NingHua Zhu HongGuang Zhang Ke Sun jianhong Ke Wei Han Wei Chen Yu Liu Xin Wang HaiQing Yuan et al. Chinese Acad Sci State Key Lab Integrated Optoelect Inst Semicond Beijing 100083 Peoples R China

A new scheme based on the electrical-filtered optical heterodyne technique is proposed for measuring the tuning speed of tunable distributed Bragg reflector (DBR) lasers. In this scheme, a 10 GHz high-pass electrical filter is used and the wavelength switching time of a tunable DBR laser for different tuning frequencies corresponding exactly to different delay lines is measured. The switching time is measured to be nearly 300 ns and can be improved by reducing the equivalent resistance-capacitance (RC) time constant of the device. The distribution of the beat signal of the DBR laser in the time domain is also obtained, and is a good match with the waveforms measured using an optical filter.

关键词： DBR激光器半导体激光器光外差技术光学滤波器测量技术可调谐速度过滤

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基于虚拟现实技术的抽水蓄能机组智慧检修仿真系统应用研究

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东方电气评论 2024年第1期38卷 20-23页

作者：屈博兴曾建宏刘芙伶蒲晓珉东方电气集团东方电机有限公司四川德阳618000 东方电气集团科学技术研究院有限公司成都611731

随着虚拟现实、三维可视化等先进计算机技术的快速发展与广泛应用,以及抽水蓄能电站建设的不断加速。针对当前发电设备制造业传统的产品服务模式与用户日益增长的对高端数字化服务需求之间的问题和矛盾,提出一种基于虚拟现实技术的抽水... 详细信息

随着虚拟现实、三维可视化等先进计算机技术的快速发展与广泛应用,以及抽水蓄能电站建设的不断加速。针对当前发电设备制造业传统的产品服务模式与用户日益增长的对高端数字化服务需求之间的问题和矛盾,提出一种基于虚拟现实技术的抽水蓄能机组智慧检修仿真系统。系统根据抽水蓄能机组设计结构特点和运维检修技术特点,将先进的虚拟现实、建模与仿真等计算机技术与抽水蓄能水泵水轮发电电动机组的运维、监测、安装、检修及培训等业务深度融合,为其他基于虚拟现实技术建设的智慧运维及检修培训系统提供参考和依据。

关键词：虚拟现实抽水蓄能机组智慧运维状态监测检修培训三维仿真人机交互

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Classification of Blood Species Using Fluorescence Spectroscopy Combined with Deep Learning Method

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Journal of Applied Mathematics and Physics 2019年第10期7卷 2324-2332页

作者： jianhong Gan Linhua Zhou Jian Cui Boqi man Xiaoning Jia Sanzhi Shi Linna Liu School of Science Changchun University of Science and Technology Changchun China Provincial Demonstration Center for Experimental Mathematics Education (Changchun University of Science and Technology) Changchun China Chinese Academy of Agricultural Sciences Changchun Veterinary Research Institute Changchun China

In this work, a deep belief neural network model (DBN) was developed to classify doves, chickens, mice and sheep blood samples, which have many similarities in composition causing their spectra to look almost identical by visual comparison alone. The DBN model was formulated for the feature extraction from the pretreated fluorescence spectroscopy. Then, cross-validation results showed that the application of deep learning method made it possible to classify the blood fluorescence spectroscopy in a more precise way than previous methods. Especially, the classification accuracy of whole blood with 1% of concentration was up to 97.5%.

关键词： Neural Network Model Deep Learning Classification Blood Species Fluorescence Spectroscopy

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