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2nd International Conference of Mechanical System Dynamics, ICMSD 2023

作者： Li, Zhiqiang Gao, Bo Yang, Zhijun Li, Yao Zhang, Zhong Science and Technology on Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment Engineering Beijing100076 China

ISBN: (纸本)9789819980475

The hot end components of aerospace vehicles cannot be completely machined into an integrated structure, so a large number of C/SiC Ceramic matrix composite connection structures are used. The connection structure of C/SiC composite materials has the characteristics of low pre-tightening force and the need for secondary deposition during the preparation process. Its tightening mechanism is different from that of metal fasteners, which makes it difficult to analyze the dynamic characteristics of the connection structure. In this paper, the Tensile testing and shear test of typical C/SiC connection structure were carried out, and the influence of contact interface SiC matrix on the structural stiffness during the preparation of the connection structure was analyzed. A dynamic modeling method for C/SiC connection structures was established by using spring elements to simulate C/SiC screws and cohesive elements to simulate the deposited substrate at the contact interface. Modal tests were conducted on C/SiC lap plates under free boundary conditions, obtaining the first five modal frequencies and modes. Based on parameter optimization methods, the stiffness of the spring element and the cohesive element were identified. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Silicon carbide

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Delay bounded routing with the maximum belief degree for dynamic uncertain networks

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Journal of Systems engineering and Electronics 2025年第1期36卷 127-138页

作者： MA Ji KANG Rui LI Ruiying ZHANG Qingyuan LIU Liang WANG Xuewang School of Reliability and Systems Engineering Beihang UniversityBeijing 100191China Science and Technology on Reliability and Environmental Engineering Laboratory Beijing 100191China International Innovation Institute Beihang UniversityHangzhou 311115China Institute of Telecommunication and Navigation Satellites China Academy of Space TechnologyBeijing 100094China

Delay aware routing is now widely used to provide efficient network transmission. However, for newly developing or developed mobile communication networks(MCN), only limited delay data can be obtained. In such a network, the delay is with epistemic uncertainty, which makes the traditional routing scheme based on deterministic theory or probability theory not applicable. Motivated by this problem, the MCN with epistemic uncertainty is first summarized as a dynamic uncertain network based on uncertainty theory, which is widely applied to model epistemic uncertainties. Then by modeling the uncertain end-toend delay, a new delay bounded routing scheme is proposed to find the path with the maximum belief degree that satisfies the delay threshold for the dynamic uncertain network. Finally, a lowEarth-orbit satellite communication network(LEO-SCN) is used as a case to verify the effectiveness of our routing scheme. It is first modeled as a dynamic uncertain network, and then the delay bounded paths with the maximum belief degree are computed and compared under different delay thresholds.

关键词： dynamic uncertain network uncertainty theory epistemic uncertainty delay bounded routing maximum belief degree

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Fault Diagnosis of Unmanned Aerial Vehicle Based on the Slime Mold Algorithm under Imbalanced Data Conditions 14

Fault Diagnosis of Unmanned Aerial Vehicle Based on the Slim...

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14th International Conference on reliability, Maintainability and Safety, ICRMS 2023

作者： Wu, Xinman Zhang, Wenjin Li, Yu Suo, Mingliang Institute of Reliability Engineering National Key Laboratory of Science and Technology on Reliability and Environmental Engineering School of Reliability and Systems Engineering Beihang University Beijing China

ISBN: (纸本)9798350329988

With the rapid progress of technology, the application of unmanned aerial vehicles (UAVs) has become widespread in various civilian and military activities. The research on fault diagnosis during a flight is a critical step towards enhancing the safety of UAV systems. Swarm-inspired heuristic algorithms have attracted significant attention owing to their fast iteration speed and strong optimization capabilities. This paper proposes a UAV fault diagnosis method based on the slime mold algorithm (SMA) under the condition of imbalanced data, thus addressing the issue of low diagnostic accuracy caused by a significantly longer normal flight time compared to the fault flight time in UAV operations. Using a real-world dataset of UAV flight faults with multiple fault patterns, the proposed approach optimizes the parameters of the support vector machine through SMA, thereby improving the fault diagnosis performance during actual UAV flights. © 2023 IEEE.

关键词： Micro air vehicle (MAV)

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The Comparison of Different Video Motion Magnification Methods in Vibration Measurement by Experimental Analysis 2nd

The Comparison of Different Video Motion Magnification Metho...

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2nd International Conference of Mechanical System Dynamics, ICMSD 2023

作者： Wei, Long Zhang, Zhong Ren, Fang Gao, Bo Hao, Ziyuan Science and Technology On Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment Engineering Beijing100076 China

ISBN: (纸本)9789819980475

In order to better use the video motion amplification method in the dynamic test of vibrating objects, it is first necessary to determine the appropriate video motion amplification algorithm. This article first briefly introduces three well known video motion magnification methods as the liner EVM, the PVM and the fast PVM. Then the performances of different video motion magnification methods are compared through cantilever vibration measurement experiments and data analysis, and finally some suggestions for selecting appropriate video motion magnification methods in vibration measurement are given. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Vibration measurement

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Giant negative electrocaloric effect measured by indirect method in X-ray irradiated P(VDF-TrFE)films

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Journal of Materiomics 2024年第3期10卷 624-631页

作者： Bo Li Bin Yang Hong Zhang Jiajia Zhang Qianjin Wang Weishu Liu Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhenGuangdong 518055China Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and TechnologyShenzhenChina College of Physics and Electronic Information Yunnan Normal UniversityYunnan Kunming 650500China The Science and Technology on Reliability Physics and Application of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research InstituteGuangzhou 510610China

Flexible solid-state cooling devices with high efficiency are attracted to ferroelectric polymers with excellent negative electrocaloric(EC)*** is challenging to obtain a large negative EC effect in ferroelectric polymers due to the lack of tunable techniques.A giant negative EC response was obtained in the poly(vinylidene fluoride-trifluoroethylene)copolymers(P(VDF-TrFE),70/30,in mole ratio)irra-diated with high-energy *** irradiated P(VDF-TrFE)films showed an adiabatic temperature change of-13.5 K at 40 MV/m under a dose of 5 Mrad(1 Mrad=10^(4) J/kg)obtained by the indirect *** significant negative EC effect is attributed to the enhancement of crystalline due to the entry of polymer molecules into the amorphous to crystalline structure and the reduction of heat ca-pacity due to the increase of *** addition,X-ray irradiation improves the dielectric coefficient from 15 to *** research indicates that irradiation can modify the negative EC properties of ferro-electric polymers for solid-state cooling.

关键词： Negative electrocaloric effects X-rays radiation P(VDF-TrFE)films

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Research on the Virtual Experiment of the Ground Active Flutter Suppression via the Receptance Method 2nd

Research on the Virtual Experiment of the Ground Active Flut...

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2nd International Conference of Mechanical System Dynamics, ICMSD 2023

作者： Yang, Zhijun Zhang, Zhong Gao, Bo Guo, Jing Science and Technology On Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment Engineering Beijing100076 China

ISBN: (纸本)9789819980475

Active flutter suppression technology can greatly expand the flight envelope of aircraft and provide technical support for aircraft weight reduction design. However, it is difficult to carry out the experiments on active flutter suppression technology, and there are great risks to verify this technology in flight test and wind tunnel test. In order to establish a safe and controllable experimental system on active flutter suppression, a virtual experimental verification model for active ground flutter suppression of aircraft wing and wing structure is presented in this paper based on the ground flutter experiment system. In the ground flutter experiment system, the rigid-flexible coupling reduced order model of wing and wing structure is established via Craig-Bampton method. The doublet lattice method is used to establish the generalized aerodynamic force based on the structural mode, and the vibrator is used to provide the excitation force to track the real-time aerodynamic signal. The receptance method is used to establish the active flutter suppression system. The simulation results show that the established virtual experiment platform for active ground flutter suppression can verify the control effect of the control system, and the Active flutter suppression system based on the receptance method can greatly improve the flutter boundary of aircraft wing and wing structure. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Flight envelopes

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Acquisition Method of Time–Frequency Distribution Based on Short-Time Fractional Fourier Transform 2nd

Acquisition Method of Time–Frequency Distribution Based on ...

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2nd International Conference of Mechanical System Dynamics, ICMSD 2023

作者： Gao, Bo Zhang, Zhong Wang, Ben Science and Technology on Reliability and Environmental Engineering Laboratory Beijing Institute of Structure and Environment Engineering Beijing100076 China

ISBN: (纸本)9789819980475

With people's attention to the non-stationary characteristics of signals, the traditional frequency domain analysis methods cannot meet the needs of non-stationary signal processing. Therefore, the time–frequency analysis method for non-stationary signals has attracted more and more attention. In this paper, in view of the demand for non-stationary signal time frequency processing, the method of fractional Fourier transform is improved, and a method of obtaining time frequency distribution with high time frequency resolution is obtained, that is, short-time fractional Fourier transform. Based on the detailed description of the calculation steps of this method, it is proved that this method has certain advantages in time frequency resolution and anti-noise interference by comparing with the short-time Fourier trans for method. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Frequency domain analysis

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Plastic quasicrystal-containing alloys prepared by annealing pseudo-high entropy Zr70-75(Al,Ni,Cu,Ag)25-30 glassy alloys

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材料科学技术（英文版） 2025年第5期208卷 1-10页

作者： Cong Liu Chen Yang Jing Ding Xiangxiang Jiang Hongzhi Luo Ao Guo Bingxiang Xu Xuefang Dai Shengli Zhu Guodong Liu State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China School of Energy and Machinery Dezhou UniversityDezhou 253023China School of Materials Science and Engineering Tianjin UniversityTianjin 300072China School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

A glassy(G)phase was formed for Zr-rich Zr70-75(Al,Ni,Cu,Ag)25_30(atomic percent,at.％)melt-spun alloy *** glassy alloys exhibit the glass transition,followed by a supercooled liquid region and then three-stage *** glass transition temperature and the onset temperature for the first-stage crystallization(Tx1)decrease from 630 to 668 K,respectively for the 70Zr alloy to 619 and 652 K,respectively for the 75Zr *** first-stage exothermic peak is due to the precipitation of an icosahedral quasicrystal(IQ)*** IQ particle size decreases from 10 nm to 6 nm with increasing Zr content from 70 at.％to 74 at.％.The[G+IQ]phases change to Zr2Ni+Zr2(Cu,Ag)phases after the second exothermic peak and then Zr2Ni+Zr2(Cu,Ag)+Zr5Al3 phases after the third *** is noticed that the as-spun glassy alloy ribbons as well as the annealed[G+IQ]phase ribbons exhibit good bending ***,the 70Zr thicker ribbons also exhibit high tensile fracture strength of 1090-1187 MPa and plastic elongation of 0.17％-0.42％.The fracture mode is similar to that of ordinary bulk metallic *** Vickers hardness(Hv)is 480 for 70Zr alloy and decreases to 436 for 75Zr *** precipitation of IQ phase causes a significant increase in Hv to about *** formations of glassy alloys with high Zr contents of 70 at.％-75 at.％by melt spinning as well as the[G+IQ]phase alloys with good bending plasticity by annealing hold promise for the creation of a new type of engineering material,transcending mere academic novelty.

关键词： Pseudo-high entropy glassy alloy Icosahedral quasicrystal Plasticity Mechanical property

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Research on Knowledge Representation Methods for Fire Incidents Based on Knowledge Graphs 5

Research on Knowledge Representation Methods for Fire Incide...

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5th International Conference on System reliability and Safety engineering, SRSE 2023

作者： Chu, Qiaohui Chen, Ying Beihang University Science and Technology on Reliability and Environmental Engineering Laboratory Beijing China

ISBN: (纸本)9798350305944

Sudden fire incidents have become one of the most frequent and common major disasters that threaten public safety and social development. The data released by authorities is mostly represented in text form, which provides limited and unclear descriptions of emergency response procedures. The low level of data structuring results in some data being unable to be effectively transformed into valuable information for reuse, leading to the wastage of data resources and hindering further processing as well as subsequent applications of case event information. In order to structure and process fire incident information, and enhance the value of information utilization for assisting decision-making, we focus on the fire incident data recorded in a state in the United States as the case data. Considering the characteristics of fire incident data, knowledge representation learning methods based on knowledge graphs such the TransE model and the TransH model are applied. By adopting the idea of distributed representation, the data is embedded into low-dimensional dense vectors, which can significantly improve computational efficiency, alleviate data sparsity issues, and meet the requirements of downstream applications. Finally, the effectiveness of the proposed research method is validated by evaluating the embedding effects of the knowledge representation process using the evaluation metrics of link prediction tasks. Our experimental results demonstrate that TransH significantly outperforms TransE on link prediction tasks. © 2023 IEEE.

关键词： Fires

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System reliability evaluation method considering physical dependency with FMT and BDD analytical algorithm

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Journal of Systems engineering and Electronics 2022年第1期33卷 222-232页

作者： CHEN Ying WANG Yanfang YANG Song KANG Rui School of Reliability and System Engineering Beihang UniversityBeijing 100191China Science and Technology on Reliability and Environmental Engineering Laboratory Beihang UniversityBeijing 100191China China Academy of Launch Vehicle Technology Bejing 100076China

Recently, the physics-of-failure(PoF) method has been more and more popular in engineering to understand the failure mechanisms(FMs) of ***, due to the lack of system modeling methods and problem-solving algorithms,the information of FMs cannot be used to evaluate system *** paper presents a system reliability evaluation method with failure mechanism tree(FMT) considering physical dependency(PDEP) such as competition, trigger, acceleration, inhibition, damage accumulation, and parameter *** the binary decision diagram(BDD) analytical algorithm is developed to establish a system reliability *** operation rules of ite operators for generating BDD are *** flow chart of system reliability evaluation method based on FMT and BDD is *** proposed method is applied in the case of an electronic controller drive *** show that the method is effective to evaluate system reliability from the perspective of FM.

关键词： system reliability modeling failure physical dependency failure mechanism tree(FMT) binary decision diagram(BDD)

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