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Reliability and reliability sensitivity analysis of structure by combining adaptive linked importance sampling and Kriging reliability method

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Chinese Journal of Aeronautics 2020年第4期33卷 1218-1227页

作者： fuchao liu Pengfei WEI Changcong ZHOU Zhufeng YUE School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710129China Institute for Risk and Reliability Leibniz Universitat HannoverCallinstr.34HannoverGermany

The application of reliability analysis and reliability sensitivity analysis methods to complicated structures faces two main challenges:small failure probability(typical less than 10-5)and time-demanding mechanical *** paper proposes an improved active learning surrogate model method,which combines the advantages of the classical Active Kriging–Monte Carlo Simulation(AK-MCS)procedure and the Adaptive Linked Importance Sampling(ALIS)*** proposed procedure can,on the one hand,adaptively produce a series of intermediate sampling density approaching the quasi-optimal Importance Sampling(IS)density,on the other hand,adaptively generate a set of intermediate surrogate models approaching the true failure surface of the rare failure ***,the small failure probability and the corresponding reliability sensitivity indices are efficiently estimated by their IS estimators based on the quasi-optimal IS density and the surrogate *** with the classical AK-MCS and Active Kriging–Importance Sampling(AK-IS)procedure,the proposed method neither need to build very large sample pool even when the failure probability is extremely small,nor need to estimate the Most Probable Points(MPPs),thus it is computationally more efficient and more applicable especially for problems with multiple *** effectiveness and engineering applicability of the proposed method are demonstrated by one numerical test example and two engineering applications.

关键词： Active learning Kriging model Adaptive linked importance sampling Reliability analysis Sensitivity analysis Small failure probability

Regional moment-independent sensitivity analysis with its applications in engineering

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Chinese Journal of Aeronautics 2017年第3期30卷 1031-1042页

作者： Changcong ZHOU Chenghu TANG fuchao liu Wenxuan WANG Zhufeng YUE School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710129 China

Traditional Global Sensitivity Analysis（GSA） focuses on ranking inputs according to their contributions to the output ***,information about how the specific regions inside an input affect the output is beyond the traditional GSA *** fully address this issue,in this work,two regional moment-independent importance measures,Regional Importance Measure based on Probability Density Function（RIMPDF） and Regional Importance Measure based on Cumulative Distribution Function（RIMCDF）,are introduced to find out the contributions of specific regions of an input to the whole output *** two regional importance measures prove to be reasonable supplements of the traditional GSA *** ideas of RIMPDF and RIMCDF are applied in two engineering examples to demonstrate that the regional moment-independent importance analysis can add more information concerning the contributions of model inputs.

关键词： Cumulative distribution function Moment-independent Probability density function Regional importance measure Sensitivity analysis Uncertainty

Ice Nucleation of Cirrus Clouds Related to the Transported Dust Layer Observed by Ground-Based Lidars over Wuhan,China

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Advances in Atmospheric Sciences 2022年第12期39卷 2071-2086页

作者： Yun HE Fan YI fuchao liu Zhenping YIN Jun ZHOU School of Electronic Information Wuhan UniversityWuhan 430072China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan 430072China State Observatory for Atmospheric Remote Sensing Wuhan 430072China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430072China

Cirrus clouds related to transported dust layers were identified on 22 occasions with ground-based polarization lidar from December 2012 to February 2018 over Wuhan(30.5°N,114.4°E),*** the events occurred in spring and *** clouds were mostly located above 7.6 km on top of the aloft dust ***-cloud relative humidity with respect to ice(RH_(i))derived from water vapor Raman lidar as well as from ERA5 reanalysis data were used as criteria to determine the possible ice nucleation *** to the two typical cases shown,the observed events can be classified into two categories:(1)category A(3 cases),in-cloud peak RH_(i)≥150%,indicating competition between heterogeneous nucleation and homogeneous nucleation;and(2)category B(19 cases),in-cloud peak RH_(i)<150%,revealing that only heterogeneous nucleation was *** nucleation generally took place during instances of cirrus cloud formation in the upper troposphere when advected dust particles were *** accompanying cloud-top temperatures ranged from–51.9℃to–30.4℃,dust-related heterogeneous nucleation contributed to primary ice nucleation in cirrus clouds by providing ice nucleating particle concentrations on the order of 10^(−3)L^(−1)to 10^(2)L^(−1).Heterogeneous nucleation and subsequent crystal growth reduced the ambient RH_(i)to be less than 150%by consuming water vapor and thus completely inhibited homogeneous nucleation.

关键词： cirrus ice nucleation polarization lidar dust ice-nucleating particle

High resolution full-spectrum water Raman lidar

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Science China(Technological Sciences) 2012年第5期55卷 1224-1229页

作者： liu fuchao YI Fan JIA JingYu ZHANG YunPeng ZHANG ShaoDong YU ChangMing TAN Ying School of Electronic Information Wuhan UniversityWuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan 430079China State Observatory for Atmospheric Remote Sensing Wuhan 430079China

Knowledge of the temporal-spatial distribution of water content in atmosphere and water phase change in cloud is important for atmospheric study. For this purpose, we have developed a high resolution full-spectrum water Raman lidar that can collect Raman signals from ice, water droplets and water vapor simultaneously. A double-grating polychromator and a 32-channel photomultiplier-tube detector are used to obtain a spectral resolution of-0.19 nm in the full Raman spectrum range of water, Preliminary observations present the water Raman spectrum characteristics of both the mixed-phase cloud and humid air under cloudless condition.

关键词： cloud water phase high spectral resolution Raman lidar

Personnel Localization Method in Transformer Substation Based on Factor Graph

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Journal of Computer and Communications 2023年第8期11卷 96-106页

作者： Haifei Yang Yuntao Zhou Huaijun Li Baojun Wu fuchao liu Status Grid Shanxi Yangquan Power Supply Company Yangquan China School of Automation Beijing Information Science & Technology University Beijing China

A SINS/GNSS location method based on factor diagram is proposed to meet the requirement of accurate location of substation construction personnel. In this paper, the inertial autonomous positioning, carrier motion information acquisition and satellite positioning technologies are integrated. The factor graph method is adopted to abstract the measurement information received by inertial navigation and satellite into factor nodes, and the state information into variable nodes, so as to construct the SINS/GNSS construction personnel positioning fusion factor graph model. The Gauss-Newton iterative method is used to implement the recursive updating of variable nodes, and the optimal estimate of the location information of the construction personnel is calculated, which realized the high precision location of the construction personnel. The factor graph method is verified by pedestrian navigation data. The results show that the factor graph method can continuously and stably output high-precision positioning results, and realize non-equidistant fusion of SINS and GNSS. The positioning accuracy is better than Kalman filter algorithm, and the horizontal positioning accuracy is less than 1 m. Therefore, the factor graph method proposed can provide accurate location information for substation construction personnel.

关键词： Personnel Positioning Factor Graph SINS/GNSS Gauss-Newton Iteration Information Fusion

Load Frequency Control of Two-Area Interconnected Power System Using Fuzzy Logic-Based PI Control Method

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Load Frequency Control of Two-Area Interconnected Power Syst...

Error Characteristics and Compensation Methods of MIMU with Non-centroid Configurations

2015年中国智能自动化学术会议

作者： Aimin An Yixin Chen Haochen Zhang fuchao liu Jingjing Zheng School of Electrical and Information Engineering Lanzhou University of Technology Institute of Electrical Power Science Electrical Power Company of Gansu Province of State Grid

Load frequency control(LFC) plays an important role to maintain the system frequency and tie-line flow at their respective scheduled values during normal period in the power system. Generally, the conventional control strategies,such as PI and PID control algorithms are applied for LFC in practical power systems. However, good control performance could not be guaranteed by using such traditional control strategies when external disturbances occur. In order to overcome the drawbacks, fuzzy logic-based proportional integral(FLPI) controller is proposed for an efficient LFC performance in this paper. Considering the reason that various disturbances and uncertainty consisting of load variation, modeling error, and structure change exist in power system, fuzzy logic modeling method is used for improving the robust performance. And a PI control strategy based on Ziegler-Nichols is used to eliminate or reduce the frequency deviation, tie-line deviation, and area control error. Finally, simulation results demonstrate that the proposed method can stabilize the two-area power system;the performance indices including settling time and overshoots of the tie-line power and frequency deviations can also be improved through the proposed method.

关键词： Load frequency control Two-area interconnected power system Fuzzy logic based proportional integral control Tie-line power Frequency deviations

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Error Characteristics and Compensation Methods of MIMU with ...

第37届中国控制会议

作者： fuchao liu Zhong Su Qing Li Chao Li Hui Zhao School of Automation Beijing Institute of Technology Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science & Technological University

In order to meet the requirements of the small guided ammunition aerodynamic layout and the internal small space assembly requirements, this paper designs a hollow and non-centroid configurations Micro-Inertial Measurement Unit. The installation position of MEMS gyros and MEMS accelerometers are given in MIMU PCB. The error characteristics of the inertial sensor are analyzed and the error model of the sensor is constructed. With high-precision three-axis turret and centrifuge equipment, applying discrete calibration algorithm to calibrate the various coefficients of the error model. The performance of the MIMU is considerably improved by detailed calibration, including temperature compensation, nonlinear error compensation, cross-coupling error compensation and so on. Focus on the analysis of the influences of center distance error for the sensors output. Finally, MIMU is equipped with a small rocket for flight test, the test results show that the MIMU designed has a certain anti-overload capability, and meet the flight environment measurement requirements.

关键词： Hollow structure non-centroid layout error modeling error compensation flight test

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甘肃酒泉风电基地风电预测预报系统

电力系统自动化 2009年第16期33卷 88-90页

作者：马彦宏汪宁渤刘福潮刘光途王蛟甘肃省电力公司风电技术中心甘肃省兰州市730070 甘肃电力信息通信中心甘肃省兰州市730050

为了解决甘肃酒泉千万千瓦风电基地大规模风电并网难题,缓解电网运行、调度和电力市场管理的压力,文中从风电场的实际情况出发,提出了风电预测预报系统的总体方案,对建设风电预测预报系统方案中的数据采集、风能预测预报和风电预测预报... 详细信息

为了解决甘肃酒泉千万千瓦风电基地大规模风电并网难题,缓解电网运行、调度和电力市场管理的压力,文中从风电场的实际情况出发,提出了风电预测预报系统的总体方案,对建设风电预测预报系统方案中的数据采集、风能预测预报和风电预测预报模式进行了研究,提出了将多种预测方法结合的解决途径。

关键词：风电监测风能预测预报风电预测预报

石英纤维/环氧树脂复合材料结构静强度的可靠度计算及全局灵敏度分析

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复合材料学报 2020年第7期37卷 1611-1618页

作者：周春苹刘付超周长聪李兴德航空工业特种所高性能电磁窗航空科技重点实验室济南250023 西北工业大学力学与土木建筑学院西安710072

以石英纤维/环氧树脂复合材料结构为研究对象,考虑设计参数的随机性,采用全局灵敏度分析理论,研究了各输入随机因素对石英纤维/环氧树脂复合材料结构静强度响应的影响。首先利用MATLAB和NASTRAN的联合仿真得到各输入变量样本值对应的输... 详细信息

以石英纤维/环氧树脂复合材料结构为研究对象,考虑设计参数的随机性,采用全局灵敏度分析理论,研究了各输入随机因素对石英纤维/环氧树脂复合材料结构静强度响应的影响。首先利用MATLAB和NASTRAN的联合仿真得到各输入变量样本值对应的输出响应值,结合自适应Kriging模型构建极限状态函数的代理模型,在此基础上实现石英纤维/环氧树脂复合材料结构静强度可靠度及各输入变量的不确定性对输出响应及失效概率全局灵敏度的计算,得到输入变量的全局灵敏度排序结果,为工程实际中复合材料结构的优化设计提供一定指导。

关键词：复合材料结构全局灵敏度分析 Kriging模型 MATLAB 可靠性