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Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-023-0748-0

摘要: One of the core challenges of intelligent fault diagnosis is that the diagnosis model requires numerous labeled training datasets to achieve satisfactory performance. Generating training data using a virtual model is a potential solution for addressing such a problem, and the construction of a high-fidelity virtual model is fundamental and critical for data generation. In this study, a digital twin-assisted dynamic model updating method for fault diagnosis is thus proposed to improve the fidelity and reliability of a virtual model, which can enhance the generated data quality. First, a virtual model is established to mirror the vibration response of a physical entity using a dynamic modeling method. Second, the modeling method is validated through a frequency analysis of the generated signal. Then, based on the signal similarity indicator, a physical–virtual signal interaction method is proposed to dynamically update the virtual model in which parameter sensitivity analysis, surrogate technique, and optimization algorithm are applied to increase the efficiency during the model updating. Finally, the proposed method is successfully applied to the dynamic model updating of a single-stage helical gearbox; the virtual data generated by this model can be used for gear fault diagnosis.

关键词: digital twin     gearbox     model construction     model updating     physical–virtual interaction    

基于子结构分析的多重子步模型修正方法

郭力,李兆霞,陈鸿天

《中国工程科学》 2006年 第8卷 第9期   页码 42-48

摘要:

为了解决模型修正过程中修正目标众多和测量信息有限的矛盾,提出了多重子步模型修正方法(MSMUM),先进行误差定位,再实现参数修正,把复杂的模型修正过程分步实现。利用子结构技术,使结构模型在整体上仅包含有限数目的子结构,对各子结构所对应的超级单元的刚度参与系数进行识别来实现误差定位,通过建立测量信息与待修正参数间的代数方程来修正误差定位后子结构内部构件的参数。数值算例表明,建立的模型修正方法有效可靠。利用建立的多重子步模型修正方法对润扬大桥南汊悬索桥桥塔模型进行了修正。

关键词: 模型修正     子结构     误差定位     参数修正     润扬桥    

Dynamic test and finite element model updating of bridge structures based on ambient vibration

HUANG Minshui, ZHU Hongping, LI Lin, GUO Wenzeng

《结构与土木工程前沿(英文)》 2008年 第2卷 第2期   页码 139-144 doi: 10.1007/s11709-008-0028-4

摘要: The dynamic characteristics of bridge structures are the basis of structural dynamic response and seismic analysis, and are also an important target of health condition monitoring. In this paper, a three-dimensional finite-element model is first established for a highway bridge over a railroad on No.312 National Highway. Based on design drawings, the dynamic characteristics of the bridge are studied using finite element analysis and ambient vibration measurements. Thus, a set of data is selected based on sensitivity analysis and optimization theory; the finite element model of the bridge is updated. The numerical and experimental results show that the updated method is more simple and effective, the updated finite element model can reflect the dynamic characteristics of the bridge better, and it can be used to predict the dynamic response under complex external forces. It is also helpful for further damage identification and health condition monitoring.

关键词: numerical     effective     Highway     vibration     complex external    

Ambient vibration testing and updating of the finite element model of a simply supported beam bridge

Ivan Gomez ARAUJO, Esperanza MALDONADO, Gustavo Chio CHO

《结构与土木工程前沿(英文)》 2011年 第5卷 第3期   页码 344-354 doi: 10.1007/s11709-011-0124-8

摘要: An ambient vibration test on a concrete bridge constructed in 1971 and calibration of its finite element model are presented. The bridge is characterized by a system of post-tensioned and simply supported beams. The dynamic characteristics of the bridge, i.e. natural frequencies, mode shapes and damping ratios were computed from the ambient vibration tests by using the Eigensystem Realization Algorithm (ERA). Then, these characteristics were used to update the finite element model of the bridge by formulating an optimization problem and then using Genetic Algorithms (GA) to solve it. From the results of the ambient vibration test of this type of bridge, it is concluded that two-dimensional mode shapes exist: in the longitudinal and transverse; and these experimentally obtained dynamic characteristics were also achieved in the analytical model through updating. The application of GAs as optimization techniques showed great versatility to optimize any number and type of variables in the model.

关键词: modal analysis     parameter identification     ambient vibration test     Eigensystem Realization Algorithm (ERA) method     finite element method    

Finite element model updating of a large structure using multi-setup stochastic subspace identification

Reza KHADEMI-ZAHEDI, Pouyan ALIMOURI

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 965-980 doi: 10.1007/s11709-019-0530-x

摘要: In the present contribution, operational modal analysis in conjunction with bees optimization algorithm are utilized to update the finite element model of a solar power plant structure. The physical parameters which required to be updated are uncertain parameters including geometry, material properties and boundary conditions of the aforementioned structure. To determine these uncertain parameters, local and global sensitivity analyses are performed to increase the solution accuracy. An objective function is determined using the sum of the squared errors between the natural frequencies calculated by finite element method and operational modal analysis, which is optimized using bees optimization algorithm. The natural frequencies of the solar power plant structure are estimated by multi-setup stochastic subspace identification method which is considered as a strong and efficient method in operational modal analysis. The proposed algorithm is efficiently implemented on the solar power plant structure located in Shahid Chamran university of Ahvaz, Iran, to update parameters of its finite element model. Moreover, computed natural frequencies by numerical method are compared with those of the operational modal analysis. The results indicate that, bees optimization algorithm leads accurate results with fast convergence.

关键词: operational modal analysis     solar power plant structure     multi-setup stochastic subspace     bees optimization algorithm     sensitivity analysis    

有限元模型修正技术的工程应用

陈德成,魏震松,曲广吉,朱安文,肖益芳

《中国工程科学》 2001年 第3卷 第10期   页码 59-63

摘要:

从工程应用的角度讨论了有限元模型修正技术的一些关键性问题,并且提出了作者的观点;提供了一个比较成熟的、达到实际工程应用水平的修正方法的基本思路和计算过程,指出了修正技术在实际应用中可能遇到的困难及其解决途径。

关键词: 有限元模型修正     实验模型     灵敏度分析     动力缩聚     频率     模态    

面向健康诊断的混凝土斜拉桥模型设计与分析

张国刚,方志,唐盛华,陈素君,陈峰

《中国工程科学》 2012年 第14卷 第11期   页码 49-56

摘要:

以广东惠州合生大桥为原型,基于相似理论面向健康诊断设计制作了1∶15的大比例混凝土斜拉桥模型,分析了模型设计中的问题及解决办法。建立了原型桥和模型桥的初始有限元模型(FEM),以实测数据对其进行修正,得到了符合实际的基准有限元模型,采用基准有限元模型对模型桥和原型桥的静动力特性及损伤状态下的损伤特性进行了计算和相似性分析。结果表明,模型设计中进行了各种简化和处理后,模型桥与原型桥的静动力性能及损伤状态下的损伤特性仍具有良好的相似性,采用该模型桥进行损伤识别试验研究能够较好地反映实际,为混凝土斜拉桥模型设计提供参考。

关键词: 混凝土斜拉桥     模型设计     模型修正     损伤诊断    

用航空航天影像更新地形图地物要素的栅格化方法

林宗坚

《中国工程科学》 2000年 第2卷 第4期   页码 43-47

摘要:

文章针对当前我国1:5和1:1万地形图更新的大规模生产的迫切需求,提出在原有地形图栅格式数字化的基础上,叠加经过精密纠正配准的航空或卫星遥感影像,以栅格方式更新地物要素的全过程方法。文中特别阐述了:1)地形图栅格数字化不同于矢量数字化的扫描采样分辨率问题;2)区别于传统的“针孔式”控制点概念的图像图形阵列控制点技术;3)由于DEM(数字高程模型)数据缺乏或精度不足引起的航空航天影像与地形图图形配准误差的局部纠正方法;4)定性指导定量的影像判读方法;5)从遥感影像提取地物结构信息的半自动化方法。文章最后列出

关键词: 测绘遥感     地形图更新     数字栅格地图    

面向数字化转型的“互联网 +”战略升级研究

何伟,张伟东,王超贤

《中国工程科学》 2020年 第22卷 第4期   页码 10-17 doi: 10.15302/J-SSCAE-2020.04.002

摘要:

“互联网 +”行动计划推出5年来,新一代信息技术创新进一步加快,经济社会数字化转型呈现诸多新特征,这就要求深入研究构建转型新体系和探索转型新路径,谋划“互联网 +”行动举措演进升级。本文遵循技术产业变革的客观规律,基于技术经济理论范式,着重分析了当前技术、应用和政策等层面数字化转型新态势和转型前沿实践探索。研究表明,当前数字化转型技术体系和技术能力日益完善,新的转型目标蓝图逐步显现,信息技术和实体经济融合进入新阶段,面临着重构数字化转型框架体系,强化转型关键要素、突破转型关键环节的重要任务。对此建议,在“互联网 +”行动后续政策设计、国家“十四五”规划制定的过程中,发掘数字化要素潜力,推动数字化转型生态建设,构建转型创新网络,升级“互联网 +”政策保障体系,推动经济社会数字化转型迈向更高发展水平。

关键词: 技术产业变革     数字化转型     互联网+     产业升级    

超临界化——优化我国火电结构应从这里起步

宋之平

《中国工程科学》 2002年 第4卷 第2期   页码 22-27

摘要:

文章认为优化火电结构应放在超临界化上,使超临界机组和超超临界机组在我国火电中占据举足轻重的比例。而且这些机组的主要性能指标以及环保性能等应不逊于同类机组的国际水平。论述了超临界技术在优化火电结构的特殊作用,指出超临界化已被证明是改造和优化火电结构的一种成功的道路,阐明了我国实施这一发展道路的必要性和可能性。

关键词: 火电结构     超临界     超超临界     可持续发展战略    

基于鲁棒法矢滤波和交替顶点更新的有效网格去噪 Article

Tao LI, Jun WANG, Hao LIU, Li-gang LIU

《信息与电子工程前沿(英文)》 2017年 第18卷 第11期   页码 1828-1842 doi: 10.1631/FITEE.1601229

摘要: 区分特征和噪声是网格去噪中最具挑战性的问题。本文基于鲁棒的引导法矢估计和交替顶点更新策略,研究了一种新的、保持特征的网格去噪方法。为了准确地捕捉特征周围的局部结构,我们提出了一种角点敏感的邻域(corner-aware neighborhood, CAN)方案。本文将CAN中所有面的总体法矢分布及其相应面的个体法矢影响相结合,提出了一种新的一致性度量方法,大大提高了引导法矢估计的可靠性。随着噪声水平的降低,我们用前次迭代的得到滤波法矢作为引导进行联合双边滤波,其思想与新出现的rolling guidance方法是一致的。在顶点更新过程中,我们在每次迭代时都根据滤波后的法线对顶点进行分类,并在各自的正则化约束下交替地对不同类型的顶点进行重新定位。对各种合成数据和实际数据的实验表明,该方法能适应高斯噪声和脉冲噪声等不同类型的噪声,且无论噪声沿法矢方向还是沿随机方向分布,都不会出现翻转的三角片。

关键词: 网格去噪;引导法矢滤波;交替顶点更新;角点敏感邻域    

具有深度阈值噪声消除的多尺度分析调制识别网络 Research Article

李响1,2,李一兵1,2,汤春瑞3,4,李迎松1,2

《信息与电子工程前沿(英文)》 2023年 第24卷 第5期   页码 742-758 doi: 10.1631/FITEE.2200253

摘要: 为了提高多变环境下调制信号识别的准确性、减少先验知识不足等因素对识别结果的影响,研究人员逐渐采用深度学习技术来替代传统的调制信号处理技术。为了解决低信噪比下调制信号识别精度低的问题,我们设计了一种具有深度阈值噪声消除的多尺度分析调制识别网络,在标签平滑的对称交叉熵函数作用下识别实际采集的调制信号。该网络由一个具有深度自适应阈值学习的消噪编码器和一个具有多尺度特征融合的解码器组成。将两个模块进行跳跃连接,共同作用以提高整体网络的鲁棒性。实验结果表明,该方法在低信噪比下比以前的方法具有更好的识别效果。该网络展示了对噪声阈值的灵活自学习能力以及所设计的特征融合模块对各种调制类型的多尺度特征获取的有效性。

关键词: 信号消噪;深度自适应阈值学习网络;多尺度特征融合;调制识别    

Standard model of knowledge representation

Wensheng YIN

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 275-288 doi: 10.1007/s11465-016-0372-3

摘要:

Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representation model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.

关键词: knowledge representation     standard model     ontology     system theory     control theory     multidimensional representation    

受限空间火灾模型研究进展

郑昕,袁宏永

《中国工程科学》 2004年 第6卷 第3期   页码 68-74

摘要:

火灾模型是从工程科学的角度出发,分析研究火灾的发生、发展,烟气蔓延以及火灾对周围环境诸如建筑设备、森林植被及大气环境等影响的数学模型。介绍了广泛应用于建筑物内部受限空间的场、区域、网模型以及经验模型的理论思想与数学方程,分析了4种模型在相应环境下应用的合理性,并对火灾模型的发展做出了展望。

关键词: 受限空间     场模型     区域模型     网模型     场区网模型     经验模型    

Elevated temperature creep model of parallel wire strands

《结构与土木工程前沿(英文)》   页码 1060-1071 doi: 10.1007/s11709-023-0981-y

摘要: Parallel wire strands (PWSs), which are widely used in prestressed steel structures, are typically in high-stress states. Under fire conditions, significant creep effects occur, reducing the prestress and influencing the mechanical behavior of PWSs. As there is no existing approach to analyze their creep behavior, this study experimentally investigated the elevated temperature creep model of PWSs. A charge-coupled camera system was incorporated to accurately obtain the deformation of the specimen during the elevated temperature creep test. It was concluded that the temperature level had a more significant effect on the creep strain than the stress level, and 450 °C was the key segment point where the creep rate varied significantly. By comparing the elevated temperature creep test results for PWSs and steel strands, it was found that the creep strain of PWSs was lower than that of steel strands at the same temperature and stress levels. The parameters in the general empirical formula, the Bailey–Norton model, and the composite time-hardening model were fitted based on the experimental results. By evaluating the accuracy and form of the models, the composite time-hardening model, which can simultaneously consider temperature, stress, and time, is recommended for use in the fire-resistance design of pre-tensioned structures with PWSs.

关键词: parallel wire strands     experimental study     elevated temperature creep model    

标题 作者 时间 类型 操作

Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

期刊论文

基于子结构分析的多重子步模型修正方法

郭力,李兆霞,陈鸿天

期刊论文

Dynamic test and finite element model updating of bridge structures based on ambient vibration

HUANG Minshui, ZHU Hongping, LI Lin, GUO Wenzeng

期刊论文

Ambient vibration testing and updating of the finite element model of a simply supported beam bridge

Ivan Gomez ARAUJO, Esperanza MALDONADO, Gustavo Chio CHO

期刊论文

Finite element model updating of a large structure using multi-setup stochastic subspace identification

Reza KHADEMI-ZAHEDI, Pouyan ALIMOURI

期刊论文

有限元模型修正技术的工程应用

陈德成,魏震松,曲广吉,朱安文,肖益芳

期刊论文

面向健康诊断的混凝土斜拉桥模型设计与分析

张国刚,方志,唐盛华,陈素君,陈峰

期刊论文

用航空航天影像更新地形图地物要素的栅格化方法

林宗坚

期刊论文

面向数字化转型的“互联网 +”战略升级研究

何伟,张伟东,王超贤

期刊论文

超临界化——优化我国火电结构应从这里起步

宋之平

期刊论文

基于鲁棒法矢滤波和交替顶点更新的有效网格去噪

Tao LI, Jun WANG, Hao LIU, Li-gang LIU

期刊论文

具有深度阈值噪声消除的多尺度分析调制识别网络

李响1,2,李一兵1,2,汤春瑞3,4,李迎松1,2

期刊论文

Standard model of knowledge representation

Wensheng YIN

期刊论文

受限空间火灾模型研究进展

郑昕,袁宏永

期刊论文

Elevated temperature creep model of parallel wire strands

期刊论文