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Remaining useful life prediction based on the wiener process for an aviation axial piston pump

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Chinese Journal of Aeronautics 2016年第3期29卷 779-788页

作者： WangXingjian LinSiru Wang Shaoping HeZhaomin ZhangChao School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Beijing Aeronautical Science&Technology Research Institute of COMAC Beijing 102211China

An aviation hydraulic axial piston pump＇s degradation fiom comprehensive wear is a typical gradual failure model. Accurate wear prediction is difficult as random and uncertain char- acteristics must be factored into the estimation. The internal wear status of the axial piston pump is characterized by the return oil flow based on fault mechanism analysis of the main frictional pairs in the pump. The performance degradation model is described by the wiener process to predict the remaining useful life （RUL） of the pump. Maximum likelihood estimation （MLE） is performed by utilizing the expectation maximization （EM） algorithm to estimate the initial parameters of the wiener process while recursive estimation is conducted utilizing the Kalman filter method to estimate the drift coefficient of the wiener process. The RUL of the pump is then calculated accord- ing to the performance degradation model based on the wiener process. Experimental results indi- cate that the return oil flow is a suitable characteristic for reflecting the internal wear status of the axial piston pump, and thus the wiener process-based method may effectively predicate the RUL of the pump.

关键词： Axial piston pump Hydraulic system Remaining useful lifeReturn oil flow Wear wiener process

Functional sample path properties of subsequence's C-R increments for a wiener process in Hlder norm

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Applied Mathematics(A Journal of Chinese Universities) 2015年第2期30卷 217-226页

作者： WEI Qi-cai School of Mathematics & Computer Science Wuhan Polytechnic University

In this paper, with the aid of large deviation formulas established in strong topology of functional space generated by HSlder norm, we discuss the functional sample path properties of subsequence＇s C-R increments for a wiener process in HSlder norm. The obtained results, generalize the corresponding results of Chen and the classic Strassen＇s law of iterated logarithm for a wiener process.

关键词： wiener process subsequence's C-R increments HSlder norm.

Exact Rates of Convergence of Functional Limit Theorems for Csorgo-Revesz Increments of a wiener process

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Acta Mathematica Sinica,English Series 2002年第4期18卷 727-736页

作者： Wen Sheng WANG Department of Mathematics. Zhejiang University, Hangzhou 310028, P. R. China Department of Mathematics. Hangzhou Teacher’s College. Hangzhou 310012. P. R. China Department of Mathematics Zhejiang University Hangzhou 310028

Let {W(t): t≥0} be a standard wiener process and S be the Strassen set of functions. We investigate the exact rates of convergence to zero (as T→∞) of the variables sup_(0≤≤T-a_T inf_(f∈S sup_(0≤r≤1 |Y_t, T(x)-f(x)] and inf_(0≤t≤T-a_T sup_(0≤x≤1|Y_(t.T)(x)-f(x)| for any given f∈S, where Y_(t.T)(x)=(W(t+xa_T)-W(t))(2a_T(logTa_T^(-1)+log logT))^(-1/2). We establish a relation between how small the increments are and the functional limit results of Csrg-Revesz increments for a wiener process. Similar results for partial sums of i.i.d, random variables are also given.

关键词： wiener process Csorgo-Revesz increment Strassen's law of the iterated logarithm

Rolling Bearing Remaining Useful Life Prediction Based on wiener process

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Journal of Dynamics, Monitoring and Diagnostics 2022年第4期1卷 229-236页

作者： Wentao Zhao Chao Zhang Shuai Wang Da Lv Oscar García Peyrano School of Mechanical Engineering Inner Mongolia University of Science and TechnologyBaotou 014010China Inner Mongolia Key Laboratory of Intelligent Diagnosis and Control of Mechatronic System Baotou 014010China Cuyo University San Carlos de BarilocheArgentina

Rolling bearing is the key part of mechanical *** prediction of bearing life can reduce maintenance costs,improve availability,and prevent catastrophic consequences,aiming at solving the problem of the nonlinear,random and small sample problems faced by rolling bearings in actual operating *** this work,the nonlinearwiener process with random effect and unbiased estimation of unknown parameters is used to predict the remaining useful life of rolling ***,random effects and nonlinear parameters are added to the traditional wiener process,and a parameter unbiased estimation method is used to estimate the positional parameters of the constructed wiener ***,the model is validated using a common set of bearing *** results show that compared with the traditional maximum likelihood function estimation method,the parameter unbiased estimation method can effectively improve the accuracy and stability of the parameter estimation *** model has a good fitting effect,which can accurately predict the remaining useful life of rolling bearing.

关键词： parameter estimation remaining useful life rolling bearing wiener process

Degradation Modeling and Parameter Estimation of Components Satisfying Nonlinear wiener process

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Degradation Modeling and Parameter Estimation of Components ...

Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

第32届中国过程控制会议(CPCC2021)

作者： Tian Yingming Qi Fei Chai Yi Lin Wenyi Li Shuo Key Laboratory of complex system safety and control Ministry of Education College of Automation Chongqing University

Degradation modeling and parameter estimation of products based on performance degradation data is the basis of prediction and health management(PHM) technology,which has attracted much attention from scholars at home and *** at the nonlinear degradation process with observed noise that usually exists in products and equipment in practical engineering applications,the nonlinear wiener process is analyzed and a nonlinear degradation model is ***,based on this model,the parameter estimation of the degradation model is realized by combining Kalman smoothing and EM algorithm to accomplish both denoising and parameter ***,the accuracy of the parameter estimation in this paper is verified by simulation data and the rotating bearing dataset provided by FEMTO-ST institution for simulation validation and example validation,respectively.

关键词： nonlinear degradation modeling wiener process parameter estimation Kalman smoothing EM algorithm

来源： cnki会议评论

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI Bao-ping FAN Hong-yan WANG Guan-nan RAO Xi GE Weifeng SHAO Xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

AN EFFICIENT FINITE DIFFERENCE METHOD FOR STOCHASTIC LINEAR SECOND-ORDER BOUNDARY-VALUE PROBLEMS DRIVEN BY ADDITIVE WHITE NOISES

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Journal of Computational Mathematics 2024年第2期42卷 432-453页

作者： Mahboub Baccouch Department of Mathematics University of Nebraska at OmahaOmaha NE 68182USA

In this paper,we develop and analyze a finite difference method for linear second-order stochastic boundary-value problems(SBVPs)driven by additive white *** we regularize the noise by the Wong-Zakai approximation and introduce a sequence of linear second-order *** prove that the solution of the SBVP with regularized noise converges to the solution of the original SBVP with convergence order O(h)in the meansquare *** obtain a numerical solution,we apply the finite difference method to the stochastic BVP whose noise is piecewise constant approximation of the original *** approximate SBVP with regularized noise is shown to have better regularity than the original problem,which facilitates the convergence proof for the proposed *** analysis is presented based on the standard finite difference method for deterministic *** specifically,we prove that the finite difference solution converges at O(h)in the mean-square sense,when the second-order accurate three-point formulas to approximate the first and second derivatives are ***,we present several numerical examples to validate the efficiency and accuracy of the proposed scheme.

关键词： Boundary-value problems Finite-difference method Additive white noise wiener process Mean-square convergence Wong-Zakai approximation

Multiscale Analysis of Semilinear Damped Stochastic Wave Equations

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Acta Mathematica Sinica,English Series 2023年第7期39卷 1305-1331页

作者： Aurelien FOUETIO Gabriel NGUETSENG Jean Louis WOUKENG Department of Mathematics Higher Teacher Training CollegeUniversity of NgaoundereP.O.Box 652BertouaCameroon Department of Mathematics University of Yaounde IP.O.Box 812YaoundeCameroon Department of Mathematics and Computer Science University of DschangP.O.Box 67DschangCameroon

In this paper we proceed with the multiscale analysis of semilinear damped stochastic wave motions. The analysis is made by combining the well-known sigma convergence method with its stochastic counterpart, associated to some compactness results such as the Prokhorov and Skorokhod theorems. We derive the equivalent model, which is of the same type as the micro-model. One of the novelties of the work is that the corrector problem is solved in the classical sense of distributions,thereby allowing numerical computations of the homogenized coefficients.

关键词： Hyperbolic stochastic equations wiener process sigma convergence tightness of probability measures

Objective Bayesian analysis for the accelerated degradation model usingwiener process with measurement errors

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Statistical Theory and Related Fields 2018年第1期2卷 27-36页

作者： Daojiang He Yunpeng Wang Mingxiang Cao Department of Statistics Anhui Normal UniversityWuhu 241003China

The wiener process as a degradation model plays an important role in the degradation *** this paper, we propose an objective Bayesian analysis for an acceleration degradation wienermodel which is subjected to measurement errors. The Jeffreys prior and reference priors underdifferent group orderings are first derived, the propriety of the posteriors is then validated. It isshown that two of the reference priors can yield proper posteriors while the others cannot. A simulation study is carried out to investigate the frequentist performance of the approach comparedto the maximum likelihood method. Finally, the approach is applied to analyse a real data.

关键词： Accelerated degradation model objective Bayesian analysis wiener process measurement errors Jeffreys prior reference prior