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Inverse reliability analysis and design for tunnel face stability considering soil spatial variability

Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1552-1564页

作者： zheming zhang Jian Ji Xiangfeng Guo Siang Huat Goh Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Department of Civil and Environmental Engineering National University of SingaporeSingapore

The traditional deterministic analysis for tunnel face stability neglects the uncertainties of geotechnical parameters,while the simplified reliability analysis which models the potential uncertainties by means of random variables usually fails to account for soil spatial *** overcome these limitations,this study proposes an efficient framework for conducting reliability analysis and reliability-based design(RBD)of tunnel face stability in spatially variable soil *** three-dimensional(3D)rotational failure mechanism of the tunnel face is extended to account for the soil spatial variability,and a probabilistic framework is established by coupling the extended mechanism with the improved Hasofer-Lind-Rackwits-Fiessler recursive algorithm(iHLRF)as well as its inverse analysis *** proposed framework allows for rapid and precise reliability analysis and RBD of tunnel face *** demonstrate the feasibility and efficacy of the proposed framework,an illustrative case of tunnelling in frictional soils is presented,where the soil's cohesion and friction angle are modelled as two anisotropic cross-correlated lognormal random *** results show that the proposed method can accurately estimate the failure probability(or reliability index)regarding the tunnel face stability and can efficiently determine the required supporting pressure for a target reliability index with soil spatial variability being taken into ***,this study reveals the impact of various factors on the support pressure,including coefficient of variation,cross-correlation between cohesion and friction angle,as well as autocorrelation distance of spatially variable soil *** results also demonstrate the feasibility of using the forward and/or inverse first-order reliability method(FORM)in high-dimensional stochastic *** is hoped that this study may provide a practical and reliable framework for determining the stability of tunnels in complex

关键词： Limit analysis Tunnel face stability Spatial variability HLRF algorithm Inverse reliability method

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Effect of disconnector and high-voltage conductor on propagation characteristics of PD-induced UHF signals

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High Voltage 2018年第3期3卷 187-192页

作者： Minxia Shi Xutao Han Xuanrui zhang zheming zhang Junhao Li State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityNo.28 West Xianning RoadXi'anPeople's Republic of China

UHF(ultra high frequency)method has been widely used in PD(partial discharge)detection for its high *** resonance,distortion,and attenuation appearing in the propagation process of UHF signals in GIS(gas insulated switchgear)will influence the real situation of PD ***,it is necessary to investigate the effect of GIS components such as disconnectors or high voltage conductors on the propagation characteristics of PD-induced UHF signals in various voltage classes *** factors of PD signals propagation characteristics in axial and radial directions are both analysed to avoid the effect caused by placement of sensor in this ***,the simulation models of GIS are built based on FDTD(finite difference time domain)*** the propagation characteristics of PD-induced UHF signals are studied in the GIS with different disconnector gap lengths and different high voltage conductor ***,the reliability of the simulation results is verified by compared with laboratory *** disconnector gap and the change of conductor radii can both result in the signals attenuation which rises highest in the direction of 180°.The lower the GIS class voltage is,the larger the attenuation of signals after passing through disconnector gap is.

关键词： propagation characteristics conductor

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An efficient probabilistic design approach for tunnel face stability by inverse reliability analysis

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Geoscience Frontiers 2021年第5期12卷 374-383页

作者： Jian Ji zheming zhang Zhijun Wu Jiacheng Xia Yongxin Wu Qing Lüc Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjingChina School of Civil Engineering Wuhan UniversityWuhanChina c College of Civil EngineeringZhejiang UniversityHangzhouChina

In order to maintain the safety of underground constructions that significantly involve geo-material uncertainties,this paper delivers a new computation framework for conducting reliability-based design(RBD)of shallow tunnel face stability,utilizing a simplified inverse first-order reliability method(FORM).The limit state functions defining tunnel face stability are established for both collapse and blow-out modes of the tunnel face failure,respectively,and the deterministic results of the tunnel face support pressure are obtained through three-dimensional finite element limit analysis(FELA).Because the inverse reliability method can directly capture the design support pressure according to prescribed target reliability index,the computational cost for probabilistic design of tunnel face stability is greatly *** comparison with Monte Carlo simulation results,the accuracy and feasibility of the proposed method are ***,this study presents a series of reliability-based design charts for vividly understanding the limit support pressure on tunnel face in both cohesionless(sandy)soil and cohesive soil stratums,and their optimal support pressure ranges are *** results show that in the case of sandy soil stratum,the blowout failure of tunnel face is extremely unlikely,whereas the collapse is the only possible failure *** parametric study of various geotechnical uncertainties also reveals that ignoring the potential correlation between soil shear strength parameters will lead to over-designed support pressure,and the coefficient of variation of internal friction angle has a greater influence on the tunnel face failure probability than that of the cohesion.

关键词： Tunnel face stability Support pressure Finite element limit analysis Inverse reliability analysis Probabilistic design

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HOLE IN THE WALL From Fireworks to Books

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城市漫步（上海版、英文） 2017年第11期 22-23页

作者： Dominic Ngai zhang zheming 不详

Project name:Reedom Bookstore Location:Changsha,Hunan Area:60 square meters Design company:Cao Pu Studio The brief:Completed in 1992,Changsha's Hunan Firework Mansion once served as the dormitory for workers at the now-defunct Firecrackers&Fireworks Import and Export *** it used to be the city s tallest building,the 17-story structure is now overshadowed by numerous skyscrap-ers,and what's left behind are retired workers and elderly residents who have nowhere else to go.

关键词： Fireworks Hunan Export

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石墨烯/三组分固体润滑剂/丁腈橡胶复合材料的制备及性能

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高分子材料科学与工程 2021年第11期37卷 94-100页

作者：张哲铭杨雪王轩海军工程大学振动与噪声研究所船舶振动噪声重点实验室海军工程大学化学与材料系湖北武汉430033

采用机械共混法制备石墨烯/三组分固体润滑剂(3phr石墨、3phrMoS_(2)、12phr聚四氟乙烯(PTFE))/丁腈橡胶复合材料,研究了复合材料的力学性能、摩擦磨损性能和摩擦振动性能,对比了经1-羟乙基-3-甲基咪唑四氟硼酸盐离子液体改性前后,石墨... 详细信息

采用机械共混法制备石墨烯/三组分固体润滑剂(3phr石墨、3phrMoS_(2)、12phr聚四氟乙烯(PTFE))/丁腈橡胶复合材料,研究了复合材料的力学性能、摩擦磨损性能和摩擦振动性能,对比了经1-羟乙基-3-甲基咪唑四氟硼酸盐离子液体改性前后,石墨烯对复合材料性能的影响。通过扫描电子显微镜观察发现,经离子液体改性后,石墨烯团聚现象明显改善,在复合材料中的分散性得到提高,对复合材料的力学性能、摩擦磨损性能和摩擦振动性能提升更为显著。填充3phr的改性石墨烯后,复合材料的拉伸强度提升11.4%、撕裂强度提升10.7%、断裂伸长率提升9.5%、压缩模量提升16.1%,复合材料在66N载荷下的环-块摩擦磨损试验中其摩擦系数降低了16.5%、体积磨损率降低了17.9%、摩擦振动减小了3.7dB。

关键词：丁腈橡胶石墨烯离子液体固体润滑剂摩擦磨损振动

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Unsupervised Feature Transfer for Batch Process Based on Geodesic Flow Kernel

Unsupervised Feature Transfer for Batch Process Based on Geo...

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第32届中国控制与决策会议

作者： zheming zhang Fang Wang Yusong Pang Gaowei Yan College of Electrical and Power Engineering Taiyuan University of Technology College of Mechanical Maritime and Materials EngineeringDelft University of Technology

The problem of misalignment of the original measurement model is caused by nonlinear,time-varying characteristic of the batch *** this paper,a method based on geodesic flow kernel（GFK） for feature transfer is *** mapping data into the manifold space,the feature transfer from source domain to target domain is *** adaptation of real-time data and modeling data is performed to reduce the distribution difference between *** historical data through distribution adaptation is used to establish a regression model to predict the real-time data,by which the unsupervised batch process soft sensor modeling is *** application of predicting the concentration of penicillin between different batches during the fermentation of penicillin demonstrated that the prediction accuracy of the model can be improved more effectively than the traditional soft sensor method.

关键词： Batch process geodesic flow kernel unsupervised feature transfer penicillin

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结合主题感知与通信代理的文本摘要模型

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西安电子科技大学学报 2020年第3期47卷 97-104页

作者：张哲铭任淑霞郭凯杰天津工业大学计算机科学与技术学院天津300387

针对传统自动文本摘要模型受循环神经网络长度限制而无法生成高质量的长文本摘要这一问题,提出了一种结合主题感知与通信代理的文本摘要模型。首先,将编码器划分为相互之间存在通信的多个代理,以解决长短期记忆网络输入序列较长而不能... 详细信息

针对传统自动文本摘要模型受循环神经网络长度限制而无法生成高质量的长文本摘要这一问题,提出了一种结合主题感知与通信代理的文本摘要模型。首先,将编码器划分为相互之间存在通信的多个代理,以解决长短期记忆网络输入序列较长而不能联合先验信息生成摘要的问题;然后,使用联合注意力机制加入主题信息,提高生成摘要与源文本的相关性;最后,使用带有强化学习的混合训练方法对模型进行训练,解决曝光偏差问题,直接对评价指标进行优化。实验结果表明,该模型不仅生成了主题突出的长文本摘要,并且得分比目前最先进的模型有一定提升。说明在主题信息的帮助下,该通信代理模型能够更好地生成长文本摘要。

关键词：自动文本摘要通信代理主题感知联合注意力机制强化学习

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Structural, magnetic and transport properties of Sc-doped La0.7Sr0.3MnO_3

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Chinese Science Bulletin 2000年第9期45卷 810-814页

作者： YAN Chunhua, HUANG Yunhui, WANG zheming, zhang Lei, GAO Song, LIAO Chunsheng & XU GuangxianState Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, China State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry Peking University Beijing China

The Sc-doped La0.7Sr0.3MnO3 polycrystallines were prepared by thermal decomposition of complexes of metal ions with ethylenediamine-tetraacetic acid (EDTA). The dependence of structural, magnetic and transport properties on Sc doping was investigated. Moderate Sc doping level results in a sharp drop in Curie temperature, an increase in resistance and enhancement of magnetoresistance effect. At temperatures above TMI, R(T) can be described as R(T) = R0exp(T0/T)1/4, which indicates that conduction takes place by hopping between the localized states. The experimental data reveal that the change in magnetoresistance property is related to the structure.

关键词： scandium perovskite colossal magnetoresistance thermal decomposition.

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考虑股道运用的重载卸车站作业计划优化研究

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铁道科学与工程学报 2024年第4期21卷 1402-1411页

作者：周汉何世伟吴艺迪张哲铭北京交通大学综合交通运输大数据应用技术交通运输行业重点实验室北京100044

重载卸车站是重载运输的重要组成部分,实现车站作业计划自动化编制对于加速列车周转时间、提高重载运输生产效率具有重要意义。重载卸车站由于列车在站作业种类多,车站作业计划编制复杂。为实现计算机自动化编制高效智能的车站作业计划... 详细信息

重载卸车站是重载运输的重要组成部分,实现车站作业计划自动化编制对于加速列车周转时间、提高重载运输生产效率具有重要意义。重载卸车站由于列车在站作业种类多,车站作业计划编制复杂。为实现计算机自动化编制高效智能的车站作业计划,在分析重载列车在车站作业流程的基础上,将重载列车在站技术作业过程转化为对卸车站内到达线股道、存车线股道、卸煤线股道、清煤线股道、组合线股道的5次占用问题,构建考虑股道运用的重载卸车站作业计划模型。考虑到模型属于NP-hard问题,设计微进化算法进行求解,并在微进化算法基础上引入大规模邻域搜索算法中的损坏和修复思想对算子操作进行改进。以朔黄铁路终端黄骅港站某夜间到达的15列重载列车为实际案例,对提出的模型和算法进行验证。研究结果表明:微进化算法所采用的优势基因结构机制能快速有效解决重载卸车站作业计划编制问题,相较于GUROBI求解器,其求解质量在95%以上且求解时间缩短48.16%,同时相较于遗传算法其求解质量提升5.38%且求解时间缩短27.49%。微进化算法得出的优化计划相较于人工编制计划,重载列车在站总时长缩短了389 min,提升了重载卸车站作业计划质量。研究结果能缩短重载列车在站作业时间,加速重载列车在站中转过程,为计算机自动编制车站作业计划提供智能决策。

关键词：重载运输车站作业计划股道运用微进化算法黄骅港站

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基于时空状态网络的高速铁路乘务交路计划优化研究

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铁道学报 2019年第9期41卷 1-11页

作者：张哲铭王莹廖正文曹文慧杭州派迩信息技术有限公司浙江杭州311100 北京交通大学交通运输学院北京100044 北京交通大学轨道交通控制与安全国家重点实验室北京100044 北京国邮科迅科技发展有限公司北京100032

乘务交路计划是同时考虑相对时间和绝对时间约束的混合时间问题,该类问题难以用时空网络描述。提出基于乘务规则的时空节点状态坐标递推原则和乘务任务可行转化判定条件,以此作为网络生成策略,构建融入乘务规则的时空状态网络,从而控制... 详细信息

乘务交路计划是同时考虑相对时间和绝对时间约束的混合时间问题,该类问题难以用时空网络描述。提出基于乘务规则的时空节点状态坐标递推原则和乘务任务可行转化判定条件,以此作为网络生成策略,构建融入乘务规则的时空状态网络,从而控制网络规模并简化数学模型复杂度。建立基于该网络的0-1整数规划模型,设计拉格朗日松弛算法,将多乘务交路组合优化问题分解为单乘务交路时空最短路径问题集合,提高求解效率。最后,以京津城际铁路和郑州东站高速铁路网为背景进行验算。结果表明:本方法不仅能有效解决高速铁路乘务交路计划问题,在求解大规模混合时间问题时也有一定效果。

关键词：乘务交路计划混合时间问题时空状态网络 0-1整数规划拉格朗日松弛

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