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Storage reliability assessment model based on competition failure of multi-components in missile

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Journal of Systems Engineering and Electronics 2017年第3期28卷 606-616页

作者： yunxiang Chen Qiang Zhang Zhongyi Cai Lili Wang Equipment Management and Safety Engineering College Air Force Engineering UniversityXi’an 710051China Defense Technology Research Academy of China Aerospace Science and Industry Corporation Beijing 100854China

The degradation data of multi-components in missile is derived by periodical testing. How to use these data to assess the storage reliability (SR) of the whole missile is a difficult problem in current research. An SR assessment model based on competition failure of multi-components in missile is proposed. By analyzing the missile life profile and its storage failure feature, the key components in missile are obtained and the characteristics voltage is assumed to be its key performance parameter. When the voltage testing data of key components in missile are available, a state space model (SSM) is applied to obtain the whole missile degradation state, which is defined as the missile degradation degree (DD). A Wiener process with the time-scale model (TSM) is applied to build the degradation failure model with individual variability and nonlinearity. The Weibull distribution and proportional risk model are applied to build an outburst failure model with performance degradation effect. Furthermore, a competition failure model with the correlation between degradation failure and outburst failure is proposed. A numerical example with a set of missiles in storage is analyzed to demonstrate the accuracy and superiority of the proposed model.

关键词： competition failure model storage reliability (SR) missile degradation degree (DD) proportional risk model individual variability

Zinc-based fiber-shaped rechargeable batteries:Insights into structures,electrodes,and electrolytes

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Nano Research 2025年第1期18卷 278-293页

作者： Xuan Zhang Hongcheng Zhang Mengxiang Chen Jingqi Lu Evgeny Zhuravlev Jing Jiang Pin Liu Shengyang Dong du Yuan Guoyin Zhu Lianbo Ma Yizhou Zhang Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science and TechnologyNanjing 210044China School of Materials Science and Engineering Anhui University of TechnologyMaanshan 243002China College of Materials Science and Engineering Changsha University of Science and TechnologyChangsha 410004China

The rapid evolution of flexible wearable electronics has spurred a growing demand for energy storage devices,characterized by low-cost manufacturing processes,high safety standards,exceptional electrochemical performance and robust mechanical *** novel flexible devices,fiber-shaped batteries(FSBs)have emerged as prominent solutions exceptionally suited to future applications,owing to their unique one-dimensional(1D)architecture,remarkable flexibility,potential for miniaturization,adaptability to deformation and compatibility with the conventional textile *** the forefront research on fiber-shaped batteries,zincbased FSBs(ZFSBs)have garnered significant attentions,featured by the promising electrochemical properties of metallic *** enthusiasm is driven by the impressive capacity of Zn(820 mAh·g^(-1))and its low redox potential(Zn/Zn^(2+):-0.76 V *** hydrogen electrode).This review aims to consolidate recent achievements in the structural design,fabrication processes and electrode materials of flexible ***,we highlight three representative structural configurations:parallel type,twisted type and coaxial *** also place special emphasis on electrode modifications and electrolyte ***,we delve into the promising development opportunities and anticipate future challenges associated with ZFSBs,emphasizing their potential roles in powering the next generation of wearable electronics.

关键词： zinc-based batteries fiber-shape parallel type twisted type coaxial type

Effect of reduction method on the performance of Pd catalysts supported on activated carbon for the selective oxidation of glucose

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Science China Chemistry 2010年第7期53卷 1598-1602页

作者： CHEN KangCheng PAN yunxiang LIU ChangJun Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical EngineeringTianjin UniversityTianjin 300072China Shanghai Research Institute of Petrochemical Technology Shanghai 201208China

The effect of the reduction method on the catalytic properties of palladium catalysts supported on activated carbon for the oxidation of D-glucose was *** reduction methods investigated include argon glow discharge plasma reduction at room temperature,reduction by flowing hydrogen at elevated temperature,and reduction by formaldehyde at room *** plasma-reduced catalyst shows the smallest metal particles with a narrow size distribution that leads to a much higher *** catalyst characteristics show that the plasma reduction increases the amount of oxygen-containing functional groups,which significantly enhances the hydrophilic property of the activated carbon and improves the dispersion of the metal.

关键词： reduction method plasma oxidation of glucose Pd catalyst activated carbon

Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge duo Xu Xiao Feng Xing Yang Zheheng Song Yuhang Song Jingyu Chen Yingcun Liu Chong Gao Yong du Zhe Sun Weilin Xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu Na Li Zhengxiang Zhou Ru Ye Liyan Zhong Yashuang Xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

Methods for predicting the remaining useful life of equipment in consideration of the random failure threshold

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Journal of Systems Engineering and Electronics 2020年第2期31卷 415-431页

作者： WANG Zezhou CHEN yunxiang CAI Zhongyi GAO Yangjun WANG Lili Equipment Management&UAV Engineering College Air Force Engineering UniversityXi’an 710051China

The value range of the failure threshold will generate an uncertain influence on the prediction results for the remaining useful life(RUL) of equipment. Most of the existing studies on the RUL prediction assume that the failure threshold is a fixed value,as they have difficulty in reflecting the random variation of the failure threshold. In connection with the inadequacies of the existing research, an in-depth analysis is carried out to study the effect of the random failure threshold(RFT) on the prediction results for the RUL. First, a nonlinear degradation model with unit-to-unit variability and measurement error is established based on the nonlinear Wiener process. Second, the expectation-maximization(EM) algorithm is used to solve the estimated values of the parameters of the prior degradation model, and the Bayesian method is used to iteratively update the posterior distribution of the random coefficients. Then, the effects of three types of RFT constraint conditions on the prediction results for the RUL are analyzed, and the probability density function(PDF) of the RUL is derived. Finally,the degradation data of aero-turbofan engines are used to verify the correctness and advantages of the method.

关键词： remaining useful life(RUL)prediction random failure threshold(RFT) nonlinear Wiener process measurement error unit-to-unit variability

Remaining useful lifetime prediction for equipment based on nonlinear implicit degradation modeling

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Journal of Systems Engineering and Electronics 2020年第1期31卷 194-205页

作者： CAI Zhongyi WANG Zezhou CHEN yunxiang GUO Jiansheng XIANG Huachun Equipment Management and UAV Engineering College Air Force Engineering University

Nonlinearity and implicitness are common degradation features of the stochastic degradation equipment for *** features have an uncertain effect on the remaining useful life(RUL)prediction of the *** current data-driven RUL prediction method has not systematically studied the nonlinear hidden degradation modeling and the RUL distribution *** paper uses the nonlinear Wiener process to build a dual nonlinear implicit degradation *** on the historical measured data of similar equipment,the maximum likelihood estimation algorithm is used to estimate the fixed coefficients and the prior distribution of a random *** the on-site measured data of the target equipment,the posterior distribution of a random coefficient and actual degradation state are step-by-step updated based on Bayesian inference and the extended Kalman filtering *** analytical form of the RUL distribution function is derived based on the first hitting time *** with the two case studies,the proposed method is verified to have certain advantages over the existing methods in the accuracy of prediction.

关键词： remaining useful life(RUL)prediction Wiener process dual nonlinearity measurement error individual difference

Finite Water Depth Effect on Wave-Body Problems Solved by Rankine Source Method

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Journal of Ocean University of China 2017年第2期16卷 191-199页

作者： FENG Aichun TANG Peng YOU yunxiang LIU Kaizhou Department of Civil and Environmental Engineering National University of Singapore College of Ocean Science and Engineering Shanghai Maritime University School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University State key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of Science

Finite water depth effect for wave-body problems are studied by continuous Rankine source method and non-desingularized *** surface and seabed surface profiles are represented by continuous panels rather than a discretization by isolated *** panels are positioned exactly on the fluid boundary surfaces and therefore no desingularization technique is *** increment method is applied for both free surface source and seabed source arrangements to reduce computational cost and improve numerical *** order Runge-Kutta iteration scheme is adopted on the free surface updating at every time *** finite water depth effect is studied quantitatively for a series of cylinders with different B/T *** accuracy and efficiency of the proposed model are validated by comparison with published numerical results and experimental *** results show that hydrodynamic coefficients vary for cylinder bodies with different ratios of B/*** certain set of B/T ratios the effect of finite water depth increases quickly with the increase of motion frequency and becomes stable when frequency is relatively *** also shows that water depths have larger hydrodynamic effects on cylinder with larger breadth to draft *** the heave added mass and damping coefficients increase across the frequency range with the water depths decrease for forced heave *** water depths have smaller effects on sway motion response than on heave motion response.

关键词： finite water depth Rankine source method continuous source panel Runge-Kutta

Remaining lifetime prediction for nonlinear degradation device with random effect

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Journal of Systems Engineering and Electronics 2018年第5期29卷 1101-1110页

作者： CAI Zhongyi CHEN yunxiang GUO Jiansheng ZHANG Qiang XIANG Huachun Equipment Management and Unmanned Aerial Vehicle Engineering College Air Force Engineering University Defense Technology Academy China Aerospace Science and Industry Corporation Limited

For the large number of nonlinear degradation devices existing in a project, the existing methods have not systematically studied the effects of random effect on the remaining lifetime(RL),the accuracy and efficiency of the parameters estimation are not high, and the current degradation state of the target device is not accurately estimated. In this paper, a nonlinear Wiener degradation model with random effect is proposed and the corresponding probability density function(PDF) of the first hitting time(FHT)is deduced. A parameter estimation method based on modified expectation maximum(EM) algorithm is proposed to obtain the estimated value of fixed coefficient and the priori value of random coefficient in the model. The posterior value of the random coefficient and the current degradation state of target device are updated synchronously by the state space model(SSM) and the Kalman filter algorithm. The PDF of RL with random effect is deduced. A simulation example is analyzed to verify that the proposed method has the obvious advantage over the existing methods in parameter estimation error and RL prediction accuracy.

关键词： remaining lifetime(RL) prediction nonlinear degradation model Wiener process random coefficient Kalman filter algorithm