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空时模型融合自注意力机制的航空管路故障诊断新方法

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振动与冲击 2024年第10期43卷 299-310页

作者：杨同光袁晟友周献文韩清凯于晓光东北大学机械工程与自动化学院沈阳110819 佛山科学技术学院机电工程与自动化学院广东佛山528225 辽宁科技大学机械工程与自动化学院辽宁鞍山114051

航空发动机外部液压管路结构复杂且管路故障信号中伴随着强大的噪声干扰,导致航空管路故障特征提取十分困难,同时目前诊断模型参数和计算量比较庞大,不适合高效地移植到移动和嵌入式设备。面对上述挑战,提出一种轻量化空时模型融合注意... 详细信息

航空发动机外部液压管路结构复杂且管路故障信号中伴随着强大的噪声干扰,导致航空管路故障特征提取十分困难,同时目前诊断模型参数和计算量比较庞大,不适合高效地移植到移动和嵌入式设备。面对上述挑战,提出一种轻量化空时模型融合注意力机制的航空发动机液压管路故障诊断新方法,并命名为S-Bi-ATM-Net模型,首先,设计轻量化管路空间特征提取模块,从而融合管路故障数据的空间特征,抽取数据的细粒度特征;然后,设计轻量化管路时间特征提取模块,从细粒度特征中继续融合管路粗粒度特征,实现粗细粒度特征融合;此外在空时模型中融合自注意力机制进行优化,使得最后的决策更加的聚焦,进一步提高所提模型的诊断精度。基于同一数据集,将所提方法与目前主流方法对比分析发现,所提方法能更准确地识别航空管路不同的故障状态,证明了所提方法的优越性和稳定性。

关键词：故障诊断空时融合轻量化注意力机制航空管路

Analytical modeling and vibration analysis of fiber reinforced composite hexagon honeycomb sandwich cylindrical-spherical combined shells

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Applied Mathematics and Mechanics(English Edition) 2022年第9期43卷 1307-1322页

作者： Hui LI Bocheng DONG Zhijiang GAO Jing ZHAO Haiyang ZhanG Xiangping WANG qingkai han School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Northeastern UniversityShenyang 110819China Key Laboratory of Impact Dynamics on Aero Engine Shenyang 110015China

This study analyzes and predicts the vibration characteristics of fiberreinforced composite sandwich(FRCS)cylindrical-spherical(CS)combined shells with hexagon honeycomb core(HHC)for the first time based on an analytical model developed,which makes good use of the advantage of the first-order shear deformation theory(FSDT),the multi-segment decomposition technique,the virtual spring technology,the Jacobi-Ritz approach,and the transfer function *** equivalent material properties of HHC are firstly determined by the modified Gibson’s formula,and the related energy equations are derived for the HHC-FRCS-CS combined shells,from which the fundamental frequencies,the mode shapes,and the forced vibration responses are *** current model is verified through the discussion of convergence and comparative analysis with the associated published literature and finite element(FE)*** effects of geometric parameters of HHC on the dynamic property of the structure are further investigated with the verified *** reveals that the vibration suppression capability can be greatly enhanced by reducing the ratio of HHC thickness to total thickness and the ratio of wall thickness of honeycomb cell to overall radius,and by increasing the ratio of length of honeycomb cell to overall radius and honeycomb characteristic angle of HHC.

关键词： analytical modeling cylindrical-spherical(CS)combined shell hexagonal honeycomb core(HHC) fiber reinforced composite(FRC) modified equivalent elastic modulus

Parameter identifications for a rotor system based on its finite element model and with varying speeds

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Acta Mechanica Sinica 2010年第2期26卷 299-303页

作者： qingkai han Hongliang Yao Bangchun Wen School of Mechanical Engineering and Automation Northeastern University 110004 Shenyang China

In order to achieve prediction for vibration of rotating machinery, an accurate finite element （FE） model and an efficient parameter identification method of the rotor system are required. In this research, a test rig is used as a prototype of a rotor system to validate a novel parameter identification technique based on an FE model. Rotor shaft vibration at varying operating speeds is measured and correlated with the FE results. Firstly, the theories of the FE modelling and identification technique are introduced. Then disk unbalance parameter, stiffness and damping coefficients of the bearing supports on the test rig are identified. The calculated responses of the FE model with identified parameters are studied in comparison with the experimental results.

关键词： Rotor system · Finite element model ·Parameter identification· Model validation

《复合材料基础与防护涂层技术应用》课程思政教学设计探究

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广东化工 2024年第8期51卷 192-194页

作者：李晖李济楠孙伟吕杭原李鹤韩清凯闻邦椿东北大学辽宁沈阳110819 东北大学航空动力装备振动及控制教育部重点实验室辽宁沈阳110819

本文在分析《复合材料基础与防护涂层技术应用》课程特点的基础上,提出了该课程的教学目标,并从知识目标、能力目标和价值观目标这三个方面进行了课程思政教学设计,以“大国工匠”精神、爱国主义情怀、科技强国思想、创新意识和职业素... 详细信息

本文在分析《复合材料基础与防护涂层技术应用》课程特点的基础上,提出了该课程的教学目标,并从知识目标、能力目标和价值观目标这三个方面进行了课程思政教学设计,以“大国工匠”精神、爱国主义情怀、科技强国思想、创新意识和职业素养等方面作为思政教学的切入点,将其与专业知识教学有机融合,培养学生“爱国敬业、勇于担当、勤于实践”的精神,让学生在学习专业知识的同时也能树立正确的价值观和人生观。并加入制备功能梯度防护涂层圆柱壳的实际教学来加深学生对该课程的理解,通过教学改革创新实现价值引领和知识传授并重的教学目标,旨在培养具有社会责任感、创新精神和实践能力的高素质学术型人才。

关键词：复合材料基础防护涂层技术应用课程思政教学设计

TRANSIENT RESPONSE OF A BI-LAYERED MULTIFERROIC COMPOSITE PLATE

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Acta Mechanica Solida Sinica 2011年第1期24卷 83-91页

作者： Ruifeng Wang qingkai han Ernian Pan Computer Modeling and Simulation Group College of Engineering University of Akron Akron Ohio 44325-3905 USA School of Mechanical Engineering and Automation Northeastern University Shenyang 110004 China

In this paper, a three-dimensional finite-element formulation for the multiferroic composite is developed and implemented into the commercial software ABAQUS for its transient analysis. First, a special three-dimensional eight-node solid element is designed to handle the multiferroic composite made of elastic, piezoelectric, and piezomagnetic materials. Second, a userdefined subroutine for this newly developed element is implemented into ABAQUS. Finally, the transient responses of a bi-layered multiferroic composite are calculated by using the direct time integration method. Two typical magnetic potential signals, Gauss and Ricker pulses, are applied to the composite with various time durations of excitation. The induced electric field shows that the transient response can be substantially influenced by the input signal, which could be tuned for the strongest electric output.

关键词： transient response multiferroic piezoelectric piezomagnetic composite finite element

EMT and MET as paradigms for cell fate switching

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分子细胞生物学报:英文版 2012年第2期4卷 66-69页

作者： Jiekai Chen qingkai han Duanqing Pei Key Laboratory of Regenerative Biology South China Institute for Stem Cell Biology and Regenerative Medicine at Guangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhou 510530China

Cell fate determination is a major unsolved problem in cell and developmental *** discovery of reprogramming by pluri-potent factors offers a rational system to investigate the molecular mechanisms associated with cell fate *** idea that reprogramming of fibroblasts starts with a mesenchymal-epithelial transition(MET)suggests that the process is perhaps a reversal of epithelial to mesenchymal transition(EMT)found frequently during early *** such,we believe that investigations into MET-EMT may yield detailed molecular insights into cell fate decisions,not only for the switching between epithelial and mesenchymal cells,but also other cell types.

关键词： EMT programming rational

Achievement of chaotic synchronization trajectories of master-slave manipulators with feedback control strategy

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Acta Mechanica Sinica 2010年第3期26卷 433-439页

作者： qingkai han Lina Hao Hao Zhang Bangchun Wen School of Mechanical Engineering and Automation Northeastern University 110004 Shenyang China

This paper addresses a master-slave synchro- nization strategy for complex dynamic systems based on feedback control. This strategy is applied to 3-DOF pla- nar manipulators in order to obtain synchronization in such complicated as chaotic motions of end-effectors. A chaotic curve is selected from Duffing equation as the trajectory of master end-effector and a piecewise approximation method is proposed to accurately represent this chaotic trajectory of end-effectors. The dynamical equations of master-slave manipulators with synchronization controller are derived, and the Lyapunov stability theory is used to determine the stability of this controlled synchronization system. In numer- ical experiments, the synchronous motions of end-effectors as well as three joint angles and torques of master-slave manipulators are studied under the control of the proposed synchronization strategy. It is found that the positive gain matrix affects the implementation of synchronization con- trol strategy. This synchronization control strategy proves the synchronization＇s feasibility and controllability for com- plicated motions generated by master-slave manipulators.

关键词： Master-slave manipulators - Chaoticsynchronization trajectory - Feedback control

A dynamic modeling approach for nonlinear vibration analysis of the L-type pipeline system with clamps

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Chinese Journal of Aeronautics 2020年第12期33卷 3253-3265页

作者： Qingdong CHAI Jin ZENG Hui MA Kun LI qingkai han School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Northeastern UniversityShenyang 110819China

There exists a lot of research on the nonlinear vibration of the pipeline system with different boundary *** the best of our knowledge,little research on the actual constraint of the clamp has been *** this paper,according to hysteresis loops of the clamp obtained from experimental test,the simplified bilinear stiffness and damping model is *** the Finite Element(FE)model of L-type pipeline system with clamps is established using Timoshenko beam theory in combination with aforementioned stiffness-damping *** hammering and shaker tests verify the FE model via the comparisons of natural frequencies and vibration *** results show that the maximum errors of natural frequencies and vibration responses are about 8.31%and 17.6%,*** proposed model can simulate the dynamic characteristics of the L-type pipeline system with clamps well,which is helpful to provide some guidance for the early design stage of pipeline in aero-engine.

关键词： Clamp Dynamic modeling Experimental test Finite element Nonlinear vibration Pipeline

PRESS-based EFOR algorithm for the dynamic parametrical modeling of nonlinear MDOF systems

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Frontiers of Mechanical Engineering 2018年第3期13卷 390-400页

作者： Haopeng LIU Yunpeng ZHU Zhong LUO qingkai han School of Mechanical Engineering and Automation Northeaste University Shenyang 110819 China Key Laboratory of Vibration and Control of Aero-Propulsion Systems (Ministry of Education) Northeastern University Shenyang 110819 China Departrnent of Automatic Control and System Engineering Sheffield University Sheffield S13JD UK School of Mechanical Engineering Dalian University of Technology Dalian 116023 China

In response to the identification problem concerning multi-degree of freedom （MDOF） nonlinear systems, this study presents the extended forward orthogonal regression （EFOR） based on predicted residual sums of squares （PRESS） to construct a nonlinear dynamic parametrical model. The proposed parametrical model is based on the non-linear autoregressive with exogenous inputs （NARX） model and aims to explicitly reveal the physical design parameters of the system. The PRESSbased EFOR algorithm is proposed to identify such a model for MDOF systems. By using the algorithm, we built a common-structured model based on the fundamental concept of evaluating its generalization capability through cross-validation. The resulting model aims to prevent over-fitting with poor generalization performance caused by the average error reduction ratio （AERR）-based EFOR algorithm. Then, a functional relationship is established between the coefficients of the terms and the design parameters of the unified model. Moreover, a 5- DOF nonlinear system is taken as a case to illustrate the modeling of the proposed algorithm. Finally, a dynamic parametrical model of a cantilever beam is constructed from experimental data. Results indicate that the dynamic parametrical model of nonlinear systems, which depends on the PRESS-based EFOR, can accurately predict the output response, thus providing a theoretical basis for the optimal design of modeling methods for MDOF nonlinear systems.

关键词： MDOF dynamic parametrical model NARX model PRESS-based EFOR cantilever beam