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Reliability-based Maintenance Optimization under Imperfect Predictive Maintenance

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 160-165页

作者： LI Changyou ZHANG Yimin xu minqiang School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Mechanical Engineering and Automa tion Northeastern UniversityShenyang 110004China

The reliability-based maintenance optimization model has been focused by the engineers and scholars but it has never been solved effectively to formulate the effect of a maintenance action on the optimization model. In existing works, the system reliability was assumed to be increased to 1 after a predictive maintenance. However, it is very difficult in the most practical systems. Therefore, a new reliability-based maintenance optimization model under imperfect predictive maintenance (PM) is proposed in this paper. In the model, the system reliability is only restored to R i (0

关键词： imperfect predictive maintenance reliability maintenance optimization cost

Rescheduling of observing spacecraft using fuzzy neural network and ant colony algorithm

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Chinese Journal of Aeronautics 2014年第3期27卷 678-687页

作者： Li Yuqing Wang Rixin xu minqiang Deep Space Exploration Research Center Harbin Institute of Technology

This paper aims at rescheduling of observing spacecraft imaging plans under uncertainties. Firstly, uncertainties in spacecraft observation scheduling are analyzed. Then, considering the uncertainties with fuzzy features, this paper proposes a fuzzy neural network and a hybrid rescheduling policy to deal with them. It then establishes a mathematical model and manages to solve the rescheduling problem by proposing an ant colony algorithm, which introduces an adaptive control mechanism and takes advantage of the information in an existing schedule. Finally, the above method is applied to solve the rescheduling problem of a certain type of earth-observing satellite. The computation of the example shows that the approach is feasible and effective in dealing with uncertainties in spacecraft observation scheduling. The approach designed here can be useful in solving the problem that the original schedule is contaminated by disturbances.

关键词： Ant colony algorithm Planning and scheduling Rescheduling Spacecraft observing Uncertainty

Fault detection of flywheel system based on clustering and principal component analysis

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Chinese Journal of Aeronautics 2015年第6期28卷 1676-1688页

作者： Wang Rixin Gong xuebing xu minqiang Li Yuqing Deep Space Exploration Research Center Harbin Institute of Technology

Considering the nonlinear, multifunctional properties of double-flywheel with closed- loop control, a two-step method including clustering and principal component analysis is proposed to detect the two faults in the multifunctional flywheels. At the first step of the proposed algorithm, clustering is taken as feature recognition to check the instructions of ＂integrated power and attitude control＂ system, such as attitude control, energy storage or energy discharge. These commands will ask the flywheel system to work in different operation modes. Therefore, the relationship of parameters in different operations can define the cluster structure of training data. Ordering points to identify the clustering structure （OPTICS） can automatically identify these clusters by the reachability-plot. K-means algorithm can divide the training data into the corresponding operations according to the teachability-plot. Finally, the last step of proposed model is used to define the rela- tionship of parameters in each operation through the principal component analysis （PCA） method. Compared with the PCA model, the proposed approach is capable of identifying the new clusters and learning the new behavior of incoming data. The simulation results show that it can effectively detect the faults in the multifunctional flywheels system.

关键词： Attitude control Cluster analysis Energy storage Fault detection Flywheels

Satellite range scheduling with the priority constraint: An improved genetic algorithm using a station ID encoding method

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Chinese Journal of Aeronautics 2015年第3期28卷 789-803页

作者： Li Yuqing Wang Rixin Liu Yu xu minqiang Deep Space Exploration Research Center Harbin Institute of Technology Harbin University of Commerce

Abstract Satellite range scheduling with the priority constraint is one of the most important prob lems in the field of satellite operation. This paper proposes a station coding based genetic algorithm to solve this problem, which adopts a new chromosome encoding method that arranges tasks according to the ground station ID. The new encoding method contributes to reducing the complex ity in conflict checking and resolving, and helps to improve the ability to find optimal resolutions. Three different selection operators are designed to match the new encoding strategy, namely ran dom selection, greedy selection, and roulette selection. To demonstrate the benefits of the improved genetic algorithm, a basic genetic algorithm is designed in which two cross operators are presented, a singlepoint crossover and a multipoint crossover. For the purpose of algorithm test and analysis, a problemgenerating program is designed, which can simulate problems by modeling features encountered in realworld problems. Based on the problem generator, computational results and analysis are made and illustrated for the scheduling of multiple ground stations.

关键词： Genetic algorithm Ground space scheduling Priority Satellite range scheduling Space communication

Approach of fault diagnosis based on similarity degree matching distance function

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Science China(Technological Sciences) 2013年第11期56卷 2709-2720页

作者： WANG RiXin JIN Yang xu minqiang Deep Space Exploration Research Center Harbin Institute and Technology

A new diagnosis method based on the similarity degree matching distance function is *** method solves the problem that the traditional fault diagnosis methods based on transition system model cannot deal with the"special state"which cannot match the target states *** evaluating the relationship between the observation and the target states,this paper first defines a new distance function based on the viewpoint of energy to measure the distance between two attribute *** that,all the distances of the attributes in the state vector are used to synthesize the distance between two *** calculating the similarity degree between two states,a trend evaluation method is *** analyzes the main direction of the trend of the state transfer according to the distances between the observation and each target state and their historical *** the diagnosis method to a primary power subsystem of a satellite,the simulation result shows that it is effective.

关键词： fault diagnosis similarity degree matching measurement-scale distance function trend evaluation

Simultaneous state and actuator fault estimation for satellite attitude control systems

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Chinese Journal of Aeronautics 2016年第3期29卷 714-721页

作者： Cheng Yao Wang Rixin xu minqiang Li Yuqing Deep Space Exploration Research Center Harbin Institute of Technology

In this paper, a new nonlinear augmented observer is proposed and applied to satellite attitude control systems. The observer can estimate system state and actuator fault simultaneously. It can enhance the performances of rapidly-varying faults estimation. Only original system matrices are adopted in the parameter design. The considered faults can be unbounded, and the proposed augmented observer can estimate a large class of faults. Systems without disturbances and the fault whose finite times derivatives are zero piecewise are initially considered, followed by a discussion of a general situation where the system is subject to disturbances and the finite times derivatives of the faults are not null but bounded. For the considered nonlinear system, convergence conditions of the observer are provided and the stability analysis is performed using Lyapunov direct method. Then a feasible algorithm is explored to compute the observer parameters using linear matrix inequalities （LMIs）. Finally, the effectiveness of the proposed approach is illustrated by considering an example of a closed-loop satellite attitude control system. The mance in estimating states and actuator faults. It also successfully. simulation results show satisfactory perfor- shows that multiple faults can be estimated

关键词： Actuator fault estimation Augmented state observer Fault diagnosis Lipschitz nonlinear systemSatellite attitude controlsystem

Multiobjective maintenance optimization of the continuously monitored deterioration system

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Journal of Systems Engineering and Electronics 2010年第5期21卷 791-797页

作者： Changyou Li minqiang xu Song Guo Rixin Wang School of Astronautics Harbin Institute of Technology Harbin 150001 P. R. China School of Mechanical Engineering and Automation Northeastern University Shenyang 110004 P. R. China School of Computer Science and Technology Harbin Engineering University Harbin 150001 P. R. China

With the development of the monitoring technology,it is more and more common that the system is continuously ***,the research on the maintenance optimization of the continuously monitored deterioration system is *** deterioration process of the discussed system is described by a Gamma *** predictive maintenance is considered to be imperfect and *** expected interval of two continuous preventive maintenances is ***,the maintenance optimization model of the continuously monitored deterioration system is *** the model,the minimization of the expected operational cost per unit time and the maximization of the system availability are the optimization *** improved ideal point method with the normalized objective functions is employed to solve the proposed *** validity and sensitivity of the proposed multiobjective maintenance optimization model are analyzed by a numerical example.

关键词： monitoring continuously multiobjective decision maintenance optimization availability cost normalized ideal point method.

Characterization of the Elastic-plastic Region Based on Magnetic Memory Effect

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 532-536页

作者： LENG Jiancheng xu minqiang LI Jianwei ZHANG Jiazhong School of Astronautics Harbin Institute of Technology Harbin 150001 China Department of Mechanical Science andEngineering Daqing Petroleum Institute Daqing 163318 China

Detecting stress concentration, especially critical stress state leading to structure damage or failure, is one of the most important tasks of equipment diagnosis. Metal magnetic memory technique needs further research to evaluate stress concentration quantitatively due to ambiguous physical mechanism, though it has potential to detect early defects in ferromagnetic materials. Mild Q235 steel defective specimens in demagnetization state were loaded in tension up to visible necking, with magnetic memory signals measurement made at increasing stress levels. Magnetic signals varied greatly under first several loadings and subsequently tended to stability in the elastic region, which showed that the magnetization always approaches the anhysteretic magnetization curve and was explained by the theory of magnetomechanical effect. In the plastic stage, an abnormal wave occurred in the stress concentration zone and its height value was sensitive to plastic deformation levels and dependent on the distance between the probe and defect, in accordance with the simulation results based on the magnetic dipole model. Different magnetic signal characteristics in the elastic-plastic region indicate that the magnetic memory technique can identify macroyielding and early damage, which is of profound significance for ensuring safe operation of equipment in service.

关键词： metal magnetic memory plastic deformation magnetomechanical effect magnetic dipole model abnormal wave

中国高端体育智库建设助力体育国际话语权提升的价值、维度及策略

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辽宁体育科技 2024年第1期46卷 56-62页

作者：董建国许民强田园山西财政税务专科学校山西太原030024 辽宁师范大学体育学院辽宁大连116029 太原理工大学体育学院山西太原030024

加强中国高端体育智库建设是助力体育国际话语权提升的重要途径。采用文献资料法,探究中国高端体育智库建设助力体育国际话语权提升的价值、维度及策略。研究认为,中国高端体育智库建设在提升中国参与全球体育治理能力、树立中国负责任... 详细信息

加强中国高端体育智库建设是助力体育国际话语权提升的重要途径。采用文献资料法,探究中国高端体育智库建设助力体育国际话语权提升的价值、维度及策略。研究认为,中国高端体育智库建设在提升中国参与全球体育治理能力、树立中国负责任的体育大国形象、推动中国体育思想与文化对外传播方面具有重要价值。中国高端体育智库与国际社会的交流互动、人才互派、成果互享、智媒互联四个维度助力体育国际话语权提升。提出以下策略:加强聚焦国际视野的体育交流合作,提升话语引导力;扩大国际化体育人才培养规模,强化话语渗透力;提升智库成果的国际影响力,增强话语创造力;注重国际化传播矩阵建设,增强话语传播力。

关键词：中国高端体育智库体育国际话语权智库建设