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基于超椭球markov的列车控制中心剩余使用寿命预测

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铁路计算机应用 2024年第2期33卷 67-73页

作者：王康齐金平嘉兴职业技术学院智能制造学院嘉兴314036 兰州交通大学机电技术研究所兰州730070

为研究设备可用度对列车控制中心(TCC,Train Control Center)的影响和预测TCC的剩余使用寿命(RUL,Remaining Useful Life),降低TCC的故障发生率,确保车辆安全运行,构建TCC动态故障树模型。通过引入markov理论,将其转化为markov模型,设计... 详细信息

为研究设备可用度对列车控制中心(TCC,Train Control Center)的影响和预测TCC的剩余使用寿命(RUL,Remaining Useful Life),降低TCC的故障发生率,确保车辆安全运行,构建TCC动态故障树模型。通过引入markov理论,将其转化为markov模型,设计了TCC可用度评估与RUL预测方法;考虑了TCC的失效率和共因失效,利用D-S(Dempster-Shafer)证据理论对失效数据作数据融合处理,得到TCC设备初始故障区间概率;在此基础上,采用超椭球模型约束设备初始故障区间概率,得到更加精确的底事件故障区间概率;画出markov状态转移图,用矩阵推导出TCC可用度和RUL的函数关系式,且对可用度的计算还考虑了维修因素。以兰州—乌鲁木齐客运专线某TCC数据作为分析案例,用该方法计算TCC及其各设备的可用度,并预测TCC的RUL。结果表明:与通用方法相比,评估结果相同,但评估信息更丰富。

关键词：列车控制中心可用度剩余使用寿命(RUL) markov 超椭球模型证据理论

基于Gamma和时变markov模型的天然气管道剩余寿命预测

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设备管理与维修 2024年第7期 38-40页

作者：李岩鹏陈博儒朱思言中国石油吉林油田分公司松原采气厂吉林松原原138000

基于Gamma和时变markov模型,对天然气管道的剩余寿命进行深入研究。采用Gamma随机过程建立管道的退化模型,以腐蚀深度为指标,并应用SY/T6151一2009标准划分了不同腐蚀状态。为更准确地模拟管道退化过程中的实际情况,引入时变转移概率矩... 详细信息

基于Gamma和时变markov模型,对天然气管道的剩余寿命进行深入研究。采用Gamma随机过程建立管道的退化模型,以腐蚀深度为指标,并应用SY/T6151一2009标准划分了不同腐蚀状态。为更准确地模拟管道退化过程中的实际情况,引入时变转移概率矩阵,考虑随时间变化的状态迁移。以APILX52级别钢制管路为对象,通过监测数据预测剩余寿命,并验证模型的准确性。结果表明,与传统的markov模型相比,该方法能够更精准地预测管道寿命的减少或延长。

关键词： Gamma markov 天然气管道剩余寿命预测

Research on security situation awareness algorithm of markov differential game block-chain model

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The Journal of China Universities of Posts and Telecommunications 2023年第4期30卷 105-120页

作者： Luo Zhiyong Wang Shuyi Song Weiwei Liu Jiahui Wang Jianming School of Computer Science and Technology Harbin University of Science and TechnologyHarbin 150080China

To analyze the impact of solar eclipse attacks on the block-chain network and comprehensively and accurately evaluate the security of the current system,a method based on the markov differential is proposed to solve the problem that it is difficult to meet the multi-stage continuous real-time randomness in the current block-chain network attack and defense process.Block-chain network security situation awareness method based on game model.This method analyzes the security data generated by the solar eclipse attack,establishes the corresponding attack graph,and classifies the offensive and defensive strengths of the offensive and defensive parties.Through a multi-stage offensive and defensive game,the security level of each node of the blockchain system is combined with the final objective function value comprehensively evaluates the real-time security status of the system.The results of simulation experiments show that the proposed model and algorithm can not only effectively evaluate the overall security of the blockchain network,but also have feasibility in predicting the future security status.

关键词： block-chain security eclipse attack game theory markov decision security situation awareness

基于KDE及markov的高速列车传动系振动评价及可靠性分析

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西南交通大学学报 2022年第4期57卷 783-790,796页

作者：刘玉梅陈云赵聪聪熊明烨吉林大学交通学院吉林长春130022 北华大学土木与交通学院吉林吉林132013 吉林农业大学工程技术学院吉林长春130118 伊利诺伊大学厄巴那−香槟分校电子与计算机学院伊利诺伊香槟IL61801

为研究高速列车运行过程中传动系的振动情况及可靠性,对CRH3型高速列车传动系关键部件的振动加速度数据进行实车采集,采用核密度估计(KDE)法对采集数据统计处理,得出各关键部件在各方向上振动响应的概率密度函数近似曲线,据此对传动系... 详细信息

为研究高速列车运行过程中传动系的振动情况及可靠性,对CRH3型高速列车传动系关键部件的振动加速度数据进行实车采集,采用核密度估计(KDE)法对采集数据统计处理,得出各关键部件在各方向上振动响应的概率密度函数近似曲线,据此对传动系的关键部件进行振动评价;通过MATLAB计算各关键部件振动加速度的最优置信区间;对传动系及传动系的关键部件定义“安全”和“故障”两种状态,建立关键部件的威布尔比例失效率模型及传动系的markov状态转移模型,以传动系当前状态为初始状态,基于实时故障率及维修率分析传动系可靠性的变化.研究结果表明:传动系中轴箱轴承、齿轮箱以及电机轴承的垂向振动最强,振动加速度集中分布在25倍、20倍、10倍重力加速度范围内,概率99.75%的均方差值分别在20.5026倍、17.6712倍、11.4693倍重力加速度内;计算得到各关键部件振动加速度概率为99.75%的最优置信区间,为系统的振动监测阈值优化及故障评估提供参考;故障率及维修率是影响传动系统状态概率的关键因素,当故障率增加30%时,系统的状态概率约下降10%,当维修率由0.05提升至0.10时,可使系统的可靠性提高20%.

关键词：高速列车振动评价核密度估计 markov 可靠性

预测水泥砒砂岩强度的markov灰色残差模型

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排灌机械工程学报 2022年第10期40卷 1014-1019页

作者：刘鑫申向东景宇任杰吕昕耿凯强董国际郝政凯内蒙古农业大学水利与土木建筑工程学院内蒙古呼和浩特010018 鄂尔多斯应用技术学院土木工程系内蒙古鄂尔多斯017010 鄂尔多斯市住房和城乡建设局建设工程质量监督站内蒙古鄂尔多斯017010

为了研究markov-灰色残差GM(1,1)模型预测水泥固化砒砂岩抗压强度的精准度和适用性,先对抗压强度数据进行了一系列的处理,建立灰色GM(1,1)模型和灰色残差GM(1,1)模型,然后基于马尔克夫过程构建markov-灰色残差GM(1,1)模型,并以此模型来... 详细信息

为了研究markov-灰色残差GM(1,1)模型预测水泥固化砒砂岩抗压强度的精准度和适用性,先对抗压强度数据进行了一系列的处理,建立灰色GM(1,1)模型和灰色残差GM(1,1)模型,然后基于马尔克夫过程构建markov-灰色残差GM(1,1)模型,并以此模型来估算水泥固化砒砂岩的抗压强度.结果表明,灰色残差GM(1,1)模型的检验精度得到了很大的提升且各项检验指标基本上都达到了1级,明显优于灰色GM(1,1)模型.马尔克夫过程便于确定残差修正值的正、负号,采用markov-灰色残差GM(1,1)模型对不同水泥掺量下90 d龄期的水泥固化砒砂岩的抗压强度进行了预测,相对误差由原来的1.77%~4.01%降低至0.60%~2.36%,平均相对误差由2.63%减小至1.25%,模型的预测精度明显提高.该研究可以为水泥固化砒砂岩以及其他水泥基工程材料抗压强度的预测提供一种简易且可靠的新方法.

关键词：砒砂岩抗压强度 markov 灰色GM(1,1)模型残差

Reliability of IEC 61850 based substation communication network architecture considering quality of repairs and common cause failures

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Protection and Control of Modern Power Systems 2022年第1期7卷 174-188页

作者： Vonani Clive Mathebula Akshay Kumar Saha School of Engineering Discipline of ElectricalElectronics and Computer EngineeringUniversity of KwaZulu-NatalDurbanSouth Africa

Mission-critical IEC 61850 system architectures are designed to tolerate hardware failures to achieve the highest reliability performance.Hence,multi-channel systems are used in such systems within industrial facilities to isolate machinery when there are process abnormalities.Inevitably,multi-channel systems introduce Common Cause Failure(CCF)since the subsystems can rarely be independent.This paper integrates CCF into the markov reliability model to enhance the model flexibility to investigate synchronous generator intra-bay SCN architecture reliability performance considering the quality of repairs and CCF.The markov process enables integration of the impact of CCF factors on system performance.The case study results indicate that CCF,coupled with imperfect repairs,significantly reduce system reliability performance.High sensitivity is observed at low levels of CCF,whereas the highest level of impact occurs when the system diagnostic coverage is 99%based on ISO 13849-1,and reduces as the diagnostic coverage level reduces.Therefore,it is concluded that the severity of CCF depends more on system diagnostic coverage level than the repair efficiency,although both factors impact the system overall performance.Hence,CCF should be con-sidered in determining the reliability performance of mission-critical communication networks in power distribution centres.

关键词： IEC 61850 Substation communication network(SCN) Reliability Common cause failure(CCF) Diagnostic coverage Repair efficiency Sensitivity Elasticity markov Matrix calculus

markov Processes and Related Topics(Ⅲ)

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Frontiers of Mathematics in China 2021年第2期16卷 255-256页

作者： Wenming HONG Yonghua MAO Yuhui ZHANG Research Center for Stochastics School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China

It is our great pleasure to present the third special issue for the markov Processes and Related Topics,on the occasion of the 20th anniversary of the Research Center for Stochastics of Beijing Normal University(BNU),supported by the innovative research group project of the National Natural Science Foundation of China.In 2002,the Research Center for Stochastics started toorganize'Workshop on markov Processes and Related Topics'.During the past 20 years,the workshop held almost each year except some special situations(for example,2003 SARS and 2020 COVID-19).Among the 16 workshops,11 of them were or will be co-organized with some universities out of Beijing。

关键词： China. markov workshop

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 aeroengines.In the time limited dispatch guidance document ARP5107B,a single-fault markov model(MM)approach is proposed for TLD analysis.However,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 certification.Firstly,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 happen.Finally,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)

Intertidal area classification with generalized extreme value distribution and markov random field in quad-polarimetric synthetic aperture radar imagery

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 253-264页

作者： Ting-ting JIN Xiao-qiang SHE Xiao-lan QIU Bin LEI Key Laboratory of Technology in Geo-spatial Information Processing and Application System Institute of ElectronicsChinese Academy of Sciences University of Chinese Academy of Sciences Huawei Software Technologies Co. Ltd.

Classification of intertidal area in synthetic aperture radar(SAR) images is an important yet challenging issue when considering the complicatedly and dramatically changing features of tidal fluctuation. The difficulty of intertidal area classification is compounded because a high proportion of this area is frequently flooded by water, making statistical modeling methods with spatial contextual information often ineffective. Because polarimetric entropy and anisotropy play significant roles in characterizing intertidal areas, in this paper we propose a novel unsupervised contextual classification algorithm. The key point of the method is to combine the generalized extreme value(GEV) statistical model of the polarization features and the markov random field(MRF) for contextual smoothing. A goodness-of-fit test is added to determine the significance of the components of the statistical model. The final classification results are obtained by effectively combining the results of polarimetric entropy and anisotropy. Experimental results of the polarimetric data obtained by the Chinese Gaofen-3 SAR satellite demonstrate the feasibility and superiority of the proposed classification algorithm.

关键词： Intertidal classification Polarimetric synthetic aperture radar Finite mixture model markov random field Generalized extreme value model