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Belief reliability modeling and analysis for TPS considering physical principles,degradation mechanism and epistemic uncertainties

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Chinese Journal of Aeronautics 2025年第5期38卷 264-276页

作者： Dayu CHEN Yao LI Yiyang SHANGGUAN Zhiqiang LI Zhenqiang WU Xiaoyang LI Rui KANG School of Reliability and Systems Engineering Beihang University Science and Technology on Reliability and Environmental Engineering Laboratory Science and Technology on Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment Engineering

Thermal Protection System(TPS) with thick tiles, low thermal conductivity, and a short re-entry stage stands as a critical element within reusable aircraft, whose reliability is related to the function and changes with their physical properties, external conditions, and degradation. Meanwhile, due to the limitation of testing resources, epistemic uncertainties stemming from the small samples are present in TPS reliability modeling. However, current TPS reliability modeling methods face challenges in characterizing the relationships among reliability and physical properties, external conditions, degradation, and epistemic uncertainties. Therefore, under the framework of belief reliability theory, a TPS reliability model is constructed, which takes into account the physical principle, external conditions, performance degradation, and epistemic uncertainties. A reliability simulation algorithm is proposed to calculate TPS reliability. Through a case study and comparison analysis, the proposed method is validated as more effective than the existing method. Additionally,reliability sensitivity analysis is conducted to identify the sensitive factors of reliability under the condition of small samples, through which suggestions are provided for TPS functional design and improvement.

关键词： Thermal protection system Physical principle Epistemic uncertainty Performance degradation Belief reliability modeling

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Robust fully spin-polarized nodal chain in 3D metal-organic framework

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材料科学技术（英文版） 2025年第5期208卷 104-110页

作者： Xiaoyu Wei Ying Liu Lei Jin Cong Liu Xuefang Dai Guodong Liu Xiaoming Zhang State Key Laboratory of Reliability and Intelligence of Electrical Equipment and School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China

The identification of fully spin-polarized topological phases in magnetic inorganic materials has attracted significant *** this study,through first-principles calculations,we characterize CrCl2(pyz)2,a metal-organic framework(MOF),as a nodal chain *** results reveal a ferromagnetic ground state in this material,presenting as a half-metal with a single spin channel near the Fermi ***-ically,the spin-down states form a nodal chain close to the Fermi level,consisting of three nodal loops protected by glide mirror symmetry on distinct ***,fully spin-polarized drumhead sur-face states corresponding to these nodal loops are identified on the material's ***,we observe the persistence of the fully spin-polarized nodal chain even when tuning the ligand rotation an-gle of the ***,our investigation delves into the influence of spin-orbit coupling(SOC)on the system,revealing that it has minimal impact on the nodal *** robustness of the nodal chain in the presence of SOC underscores its intriguing and resilient nature,indicating its potential utility in various electronic ***,the robust realization of a fully spin-polarized nodal chain in this magnetic MOF system holds promise for applications in the realm of spintronics.

关键词： Topology MOFS Half-metal Fully spin-polarized Nodal chain

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Rational design of superior catalysts from topological semimetals with nontrivial energy window

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Rare Metals 2024年第5期43卷 1956-1964页

作者： Min Zhao Li-Rong Wang Wei Liu Ming-Hang Li Ying Liu Xue-Fang Dai Guo-Dong Liu Xiao-Ming Zhang Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Materials Science and Engineering ManufacturingHebei University of TechnologyTianjin 300130China

Materials featuring topological energy bands and nontrivial surface states hold significant promise in unlocking unprecedented opportunities for innovating electrocatalytic ***,it remains a challenge to realize superior topological catalysts which can carry both high catalytic activity and excellent catalytic ***,we propose that a family of Ni-based binary materials hosting fantasying topological conjunct-nodalpoint state and a large nontrivial energy window(NEWD)represents an ideal choice for such superior topological catalysts in hydrogen evolution *** presence of conjunct-nodal-points ensures long Fermi arcs on the surface,thereby enabling an extremely high catalytic *** NEWD plays a crucial role in stabilizing the high catalytic activity against external perturbations,such as strain and electron/hole *** roles for conjunctnodal-points and NEWD are substantiated by the observable weakening of catalytic performance during topological phase transitions,which result in the removal of the conjunct-nodal-points,NEWD and their corresponding long Fermi *** work unveils a hidden mechanism and opens a feasible route for developing superior quantum catalysts from novel topology point of view.

关键词： First-principles modeling Topological semimetal Nontrivial surface states Hydrogen evolution reaction

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Simulation and Experiment of Windage Power Loss of A Shrouded Spiral Bevel Gears under Oil Injection Lubrication

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Chinese Journal of Mechanical engineering 2025年第2期38卷 413-432页

作者： Bo Li Kai Rong Xuyang Zhang Sanmin Wang U-Xuan Tan Xuanyuan Su Laifa Tao School of Mechanical Engineering Northwestern Polytechnical University Department of Engineering Product Development Singapore University of Technology and Design Hangzhou International Innovation Institute Beihang University National Key Laboratory of Science and Technology on Reliability and Environmental Engineering School of Reliability and Systems Engineering Beihang University

During high-speed rotation, the surface of aeronautic spiral bevel gears will generate significant pressure and viscous forces, which will cause a certain amount of windage power loss and reduce the efficiency of the transmission system. Based on the computational fluid dynamics, this paper analyzes the windage power loss of a single spiral bevel gear and a spiral bevel gear pair under oil injection lubrication. In addition, the shroud is used to suppress gear windage loss, and the clearance size and opening angle of the designed shroud are optimized. Finally, by comparing and analyzing the experimental results, the following conclusions were obtained:(1) For a single gear, the speed is the most important factor affecting windage loss, followed by the hand of spiral, and rotation direction;(2) For gear pairs, under oil injection lubrication, the input speed has the greatest impact on windage power loss, followed by the influence of oil injection port speed, temperature and oil injection port pressure;(3) Installing a shroud is an effective method to reduce windage power loss;(4) In the pure air phase, the smaller the clearance between the shroud and the gear surface, and the smaller the radial direction between the shroud and the shaft, the better the effect of reducing windage;(5) In the two-phase flow of oil and gas, it is necessary to design oil drainage holes on the shroud to ensure the smooth discharge of lubricating oil and improve the drag reduction effect.

关键词： Computational fluid dynamics (CFD) Oil injection lubrication Shroud Spiral bevel gear Windage power loss

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Iron-induced NaTi2（PO4）3 with regulated electronic structure enables freshwater harvesting based on rocking-chair desalination battery

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science China Chemistry 2025年第5期68卷 2178-2187页

作者： Yuliang Wu Chen Ling Chaolin Li Wenhui Wang School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen School of Environment and Resources Taiyuan University of Science and Technology State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

Despite the promising potential of NaTi2（PO4）3as desalination battery electrode,its mediocre seawater desalination capacity and durability fail to meet the requirements of practical ***,the substitution of Ti by Fe in NaTi2（PO4）3(NT2-xFxP),which possesses a stronger electronegativity relative to Ti,can regulate the electronic structure,thus facilitating charge transfer and ion diffusion during the desalination *** kinetic and thermodynamic facilitation of NT2-xFxP is clarified by the electrochemical analyses and DFT ***,the additional redox center and solid-solution reaction mechanism induced by Fe-dopant further contribute to a superior desalination performance of NT2-xFxP in different seawater *** from the multifunctional effect of Fe-dopant,the optimal NT1.7F0.3P delivers a large salt removal capacity(173.6 mg g-1) with an ultrahigh salt removal rate(8.48 mg g-1min-1),and maintains 96.6%of desalination capacity after 500 cycles in natural ***,the assembled NT1.7F0.3P||NaFeHCF rocking-chair desalination battery（RCDB） demonstrates a higher desalination performance than that of reported RCDB systems,and can desalinate natural seawater to freshwater standards under continuous desalination mode for the first time in RCDB *** work provides a facile but effective strategy to modulate the electronic structure of NaTi2（PO4）3for RCDB,and exploits a new perspective for developing scalable RCDB devices for continuous desalinating real seawater to freshwater.

关键词： NASICON-type NaTi2(PO4)3 electronic structure electrodes seawater desalination rocking-chair desalination battery

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Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

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science China(Technological sciences) 2025年第2期68卷 136-152页

作者： Kuangda CHEN Huan ZHAO Jiexin ZHANG Mei FENG Yiwei WANG Jinliang WANG Han DING State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of CNC Equipment Reliability Ministry of EducationJilin UniversityChangchun 130021China School of Medical Equipment Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Narrow space manipulations are crucial for equipment maintenance,as they eliminate the need for disassembly,thus reducing costs and increasing ***-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces,thanks to their interaction compliance and distal ***,their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation *** address this challenge,this paper proposes a novel type of rigid-flexible coupling robot,which increases the stiffness of the robot while ensuring the reachability within a narrow *** achieve high-accuracy location in a narrow space,kinematic and control methods are ***,the robot forward kinematics are uniformly represented,and the closed-form inverse kinematics solution is ***,in cases where the robot's structure fails to align with Pieper's solution,a two-stage search strategy is utilized to solve the inverse kinematics,resulting in a high success rate of 99.1%.Based on the proposed kinematics,a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow *** practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

关键词： narrow space manipulation rigid-flexible coupling robot kinematics rigid-dominated control

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Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

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Defence technology（防务技术） 2024年第3期33卷 186-196页

作者： Yujie Yan Bo Jin Rufang Peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center *** carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature *** was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the *** investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal *** carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 *** to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) Chitosan Co Ammonium perchlorate Pyrolysis kinetics

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Coexistence behavior of asymmetric attractors in hyperbolic-type memristive Hopfield neural network and its application in image encryption

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Chinese Physics B 2024年第3期33卷 302-315页

作者：李晓霞何倩倩余天意才壮徐桂芝 Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province Hebei University of TechnologyTianjin 300130China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300130China School of Life Science & Health Engineering Hebei University of TechnologyTianjin 300130China

The neuron model has been widely employed in neural-morphic computing systems and chaotic *** study aims to develop a novel circuit simulation of a three-neuron Hopfield neural network(HNN)with coupled hyperbolic memristors through the modification of a single coupling connection *** bistable mode of the hyperbolic memristive HNN(mHNN),characterized by the coexistence of asymmetric chaos and periodic attractors,is effectively demonstrated through the utilization of conventional nonlinear analysis *** techniques include bifurcation diagrams,two-parameter maximum Lyapunov exponent plots,local attractor basins,and phase trajectory ***,an encryption technique for color images is devised by leveraging the mHNN model and asymmetric structural *** method demonstrates significant benefits in correlation,information entropy,and resistance to differential attacks,providing strong evidence for its effectiveness in ***,an improved modular circuit design method is employed to create the analog equivalent circuit of the memristive *** correctness of the circuit design is confirmed through Multisim simulations,which align with numerical simulations conducted in Matlab.

关键词： hyperbolic-type memristor Hopfield neural network(HNN) asymmetric attractors image encryption

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Dynamic Characteristics Analysis of Connection Structure of C/SiC Ceramic Matrix Composites 2nd

Dynamic Characteristics Analysis of Connection Structure of ...

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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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Study on concentration distribution and detonation characteristics for non-axisymmetric fuel dispersal

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Defence technology（防务技术） 2024年第1期31卷 484-495页

作者： Linghui Zeng Zhongqi Wang Xing Chen Jianping Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China College of Environment and Chemical Engineering Sichuan University of Science&EngineeringZigong643000China

The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation fields of 85 kg cylindrical and fan-shaped fuel are investigated by experiments and numerical simulations.A dynamic model of the whole process for fuel dispersal and detonation is *** concentration distribution of fuel is used as the initial condition to calculate the detonation stage,thus solving the initial value problem of detonation *** phase and component changes of fuel cloud at different locations are *** fuel cloud is divided into directions of 0°,90°,135°and 180°.The results show that the maximum cloud radius is 20.94 m in 135°and the minimum is 12.04 m in 0°.The diameter of the detonation fireball is 53.6 m,and the peak temperature is 3455 *** highest peak overpressure is 3.44 MPa in 0°and the lowest is 2.97 MPa in 135°.The proportion of liquid phase in 0°is22.90%,and the fuel loss is 11.8% and 9% higher than that in 135°and cylindrical charge,*** stable propagation distance of blast wave in 135°is 42.50% longer than 0°and 28.37% longer than cylindrical charge.

关键词： Fuel dispersal Concentration distribution Detonation characteristic Fuel loss Numerical simulation

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