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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan Zhang Yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China college of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong Hu Wenyi Lian Kang Hu Qiuju Li Xueliang Cui Tengyu Yao Laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： Li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)

Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU W.M.HUANG college of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

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Evaluation of aileron actuator reliability with censored data

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Chinese Journal of aeronautics 2015年第4期28卷 1087-1103页

作者： Li Huaiyuan Zuo Hongfu Liu Ruochen Liu Junqiang Jing Cai college of civil aviation Nanjing University of Aeronautics and Astronautics

For the purpose of enhancing reliability of aileron of Airbus new-generation A350 XWB,an evaluation of aileron reliability on the basis of maintenance data is presented in this *** maintenance data contains large number of censoring samples, information uncertainty of which makes it hard to evaluate reliability of aileron *** that true lifetime of censoring sample has identical distribution with complete sample, if censoring sample is transformed into complete sample, conversion frequency of censoring sample can be estimated according to frequency of complete *** the one hand, standard life table estimation and product limit method are improved on the basis of such conversion frequency, enabling accurate estimation of various censoring *** the other hand, by taking such frequency as one of the weight factors and integrating variance of order statistics under standard distribution, weighted least square estimation is formed for accurately estimating various censoring *** amounts of experiments and simulations show that reliabilities of improved life table and improved product limit method are closer to the true value and more conservative; moreover, weighted least square estimate（WLSE）, with conversion frequency of censoring sample and variances of order statistics as the weights, can still estimate accurately with high proportion of censored data in *** in this paper has good effect and can accurately estimate the reliability of aileron actuator even with small sample and high censoring *** research has certain significance in theory and engineering practice.

关键词： Ailerons civil aimraft Non-parametric data distri-butions Order statistics Parameter estimation Reliability estimation Weight

Effect of interface debonding on matrix multicracking evolution of fiber-reinfroced ceramic-matrix composites

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航空动力学报 2016年第3期31卷 527-538页

作者： LI Long-biao college of civil aviation Nanjing University of Aeronautics and Astronautics

An analytical methodology was developed to investigate the effect of fiber/matrix interface debonding on matrix multicracking evolution of fiber-reinforced CMCs(ceramic-matrix composites).The Budiansky-Hutchinson-Evans shear-lag model was adopted to analyse the micro-stress field of the damaged *** critical matrix strain energy criterion,which presupposes the existence of an ultimate or critical matrix strain energy with matrix,was obtained to simulate the matrix multicracking evolution of *** the increase of the applied stress,the matrix multicracking and fiber/matrix interface debonding occurred to dissipate the additional energy entered into the *** fiber/matrix interface debonded length under matrix multicracking evolution was obtained by treating the interface debonding as a particular crack propagation *** conditions for no-debonding and debonding during the evolution of matrix multicracking were discussed in terms of two interfacial properties,i.e.,the interface shear stress and interface debonded *** the fiber/matrix interface was bonded,the matrix multicracking evolution was much more intense compared with the interface debonding;when the fiber/matrix interface was debonded,the matrix crack density increased with the increasing of interface shear stress and interface debonded *** theoretical results were compared with experimental data of unidirectional SiC/CAS(calcium alumina silicate),SiC/CAS-Ⅱand SiC/borosilicate composites.

关键词： ceramic-matrix composites(CMCs) matrix cracking interface debonding micromechanics critical matrix strain energy

Remaining useful life prognostics for aeroengine based on superstatistics and information fusion

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Chinese Journal of aeronautics 2014年第5期27卷 1086-1096页

作者： Liu Junqiang Zhang Malan Zuo Hongfu Xie Jiwei college of civil aviation Nanjing University of Aeronautics and Astronautics

Remaining useful life（RUL） prognostics is a fundamental premise to perform conditionbased maintenance（CBM） for a system subject to performance degradation. Over the past decades,research has been conducted in RUL prognostics for aeroengine. However, most of the prognostics technologies and methods simply base on single parameter, making it hard to demonstrate the specific characteristics of its degradation. To solve such problems, this paper proposes a novel approach to predict RUL by means of superstatistics and information fusion. The performance degradation evolution of the engine is modeled by fusing multiple monitoring parameters, which manifest non-stationary characteristics while degrading. With the obtained degradation curve,prognostics model can be established by state-space method, and then RUL can be estimated when the time-varying parameters of the model are predicted and updated through Kalman filtering algorithm. By this method, the non-stationary degradation of each parameter is represented, and multiple monitoring parameters are incorporated, both contributing to the final prognostics. A case study shows that this approach enables satisfactory prediction evolution and achieves a markedly better prognosis of RUL.

关键词： Degradation Information fusion Kalman filtering Performance Prognostics Remaining useful life Superstatistics

Accuracy analysis of a single-fault Markov model for FADEC system

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Journal of Systems Engineering and Electronics 2019年第5期30卷 1044-1052页

作者： CAI Jing HU Wei CAI Kunye college of civil aviation Nanjing University of Aeronautics and Astronautics

Time-limited dispatching(TLD)analysis of the full authority digital engine control(FADEC)systems is an important part of the aircraft system safety analysis and a necessary task for the certification of commercial aircraft and *** the time limited dispatch guidance document ARP5107B,a single-fault Markov model(MM)approach is proposed for TLD ***,ARP5107B also requires that the loss of thrust control(LOTC)rate error calculated by applying the single-fault MM must be less than 5%when performing airworthiness ***,the sources of accuracy errors in three kinds of MM are analyzed and specified through a case study of the general FADEC system,and secondly a two-fault MM considering maintenance policy is established through analyzing and calculating the expected repair time when two related faults ***,a specific FADEC system is given to study on the influence factors of accuracy error in the single-fault MM,and the results show that the accuracy error of the single-fault MM decreases with the increase of short or long prescribed dispatch time,and the range values of short time(ST)and long time(LT)are determined to satisfy the requirement of accuracy error within 5%.

关键词： full authority digital engine control(FADEC)system Markov model(MM) accuracy analysis loss of thrust control(LOTC)

Robust LPV modeling and control of aircraft flying through wind disturbance

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Chinese Journal of aeronautics 2019年第7期32卷 1588-1602页

作者： Zhenxing GAO Jun FU college of civil aviation Nanjing University of Aeronautics and Astronautics

This article deals with the disturbance attenuation control of aircraft flying through wind shear via Linear Parameter Varying(LPV) modeling and control method. A Flight Dynamics Model(FDM) with wind shear effects considered was established in wind coordinate system. An LPV FDM was built up based on function substitution whose decomposing function was optimized by Genetic Algorithm(GA). The wind disturbance was explicitly included in the system matrix of LPV FDM. Taking wind disturbance as external uncertainties, robust LPV control method with the LPV FDM was put forward. Based on ride quality and flight safety requirements in wind disturbance, longitudinal and lateral output feedback robust LPV controllers were designed respectively,in which the scheduling flight states in LPV model were actually dependent parameters in LPV control. The results indicate that LPV FDM can reflect the instantaneous dynamics of nonlinear system especially at the boundary of aerodynamic envelope. Furthermore, the LPV FDM also can approach nonlinear FDM’s response in wind disturbance special flight. Compared with a parameter-invariant LQR controller designed with a small-disturbance FDM, the LPV controllers show preferable robustness and stability for disturbance attenuation.

关键词： Function substitution Linear parameter varying LPV control Robust control Wind shear

Novel approach of crater detection by crater candidate region selection and matrix-pattern-oriented least squares support vector machine

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Chinese Journal of aeronautics 2013年第2期26卷 385-393页

作者： Ding Meng Cao Yunfeng Wu Qingxian college of civil aviation Nanjing University of Aeronautics and Astronautics college of Automation Engineering Nanjing University of Aeronautics and Astronautics

Impacted craters are commonly found on the surface of planets, satellites, asteroids and other solar system bodies. In order to speed up the rate of constructing the database of craters, it is important to develop crater detection algorithms. This paper presents a novel approach to automatically detect craters on planetary surfaces. The approach contains two parts： crater candidate region selection and crater detection. In the first part, crater candidate region selection is achieved by Kanade-Lucas-Tomasi （KLT） detector. Matrix-pattern-oriented least squares support vector machine （MatLSSVM）, as the matrixization version of least square support vector machine （SVM）, inherits the advantages of least squares support vector machine （LSSVM）, reduces storage space greatly and reserves spatial redundancies within each image matrix compared with general LSSVM. The second part of the approach employs MatLSSVM to design classifier for crater detection. Experimental results on the dataset which comprises 160 preprocessed image patches from Google Mars demonstrate that the accuracy rate of crater detection can be up to 88%. In addition, the outstanding feature of the approach introduced in this paper is that it takes resized crater candidate region as input pattern directly to finish crater detection. The results of the last experiment demonstrate that MatLSSVM-based classifier can detect crater regions effectively on the basis of KLT-based crater candidate region selection.

关键词： Crater candidate region Crater detection algorithm Kanade–Lucas–Tomasi detector Least squares support vector machine Matrixization

Modal identification based on Hilbert-Huang Transform of structural response with S VD preprocessing

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Acta Mechanica Sinica 2009年第6期25卷 883-888页

作者： Min Zheng Fan Shen Yuping Dou Xiaoyan Yan college of civil aviation,nanjing university of aeronautics and astronautics,210016 nanjing. China college of civil aviation Nanjing University of Aeronautics and Astronautics Nanjing China

In recent years, Empirical mode decomposition and Hilbert spectral analysis have been combined to identify system parameters. Singular-Value Decomposition is pro- posed as a signal preprocessing technique of Hilbert-Huang Transform to extract modal parameters for closely spaced modes and low-energy components. The proposed method is applied to a simulated airplane model built in Automatic Dynamic Analysis of Mechanical Systems software. The results demonstrate that the identified modal parameters are in good agreement with the baseline model.

关键词： Modal identification . Hilbert-Huang Transforms - Singular-value decomposition . Signal processing