The traditional fault diagnosis method is completely based on the fault symptom without considering failure rate,so the fault diagnosis accuracy is not ideal.To improve the correctness rate of fault diagnosis,the pape...The traditional fault diagnosis method is completely based on the fault symptom without considering failure rate,so the fault diagnosis accuracy is not ideal.To improve the correctness rate of fault diagnosis,the paper proposes a fault diagnosis method of equipment based on failure rate and fault symptom.Firstly,an algorithm for calculating the equipment failure rate is proposed based on Weibull distribution model;Secondly,the probability of fault existence is evaluated based on fault symptom;Thirdly,a new fault diagnosis model is herein presented based on fault rate and fault symptom;Finally,the method is proved to be applicable through an example.The method takes failure rate,fault mechanism,fault symptom,difficulty degree of symptom acquisition and other factors into consideration,so the fault diagnosis accuracy is improved greatly.展开更多
The technology of diagnostic symptom identification of nonlinear vibration is based on a database of a diagnostic case. This paper defines the periodic degree, quasi periodic degree, and chaotic degree of a Poincare ...The technology of diagnostic symptom identification of nonlinear vibration is based on a database of a diagnostic case. This paper defines the periodic degree, quasi periodic degree, and chaotic degree of a Poincare map, an iterated map, and adopts the image identification theory, so the three states of periodic, quasi periodic, and chaotic running states of a machine can be distinguished. It also defines the variable identity, rotating angle and spread degree. The database of diagnostic case is expressed by means of an access database. The diagnostic symptoms are identified using the difference between the Poincare maps of samples and the fault case.Finally, we demonstrate an identification system of a nonlinear vibration diagnostic symptom of large rotating machinery.展开更多
网络虚拟化环境下,底层网络的透明性造成虚拟网提供商不能诊断所有的虚拟网服务故障.为解决此问题,提出了基于映射关系的虚拟网服务故障传播模型.针对故障传播模型中故障集与症状集较大、网络环境动态和噪声大而导致的已有诊断算法误报...网络虚拟化环境下,底层网络的透明性造成虚拟网提供商不能诊断所有的虚拟网服务故障.为解决此问题,提出了基于映射关系的虚拟网服务故障传播模型.针对故障传播模型中故障集与症状集较大、网络环境动态和噪声大而导致的已有诊断算法误报率高、时间复杂度高的问题,基于网络虚拟化环境下症状内在相关性特点,提出了一种新的基于症状内在相关性的虚拟网服务故障诊断算法SFDoIC(service fault diagnosis algorithm based on inherent correlation among symptoms).仿真实验结果表明,SFDoIC算法能够很好地解决底层网络透明性造成的虚拟网服务故障难以定位的问题.SFDoIC算法可以有效地降低诊断算法的误报率,显著缩短诊断算法的运行时间.展开更多
基金supported by Jiangsu Key Laboratory of Recycling and Reuse Technology for Mechanical and Electronic Products(RRME-KF1605)。
文摘The traditional fault diagnosis method is completely based on the fault symptom without considering failure rate,so the fault diagnosis accuracy is not ideal.To improve the correctness rate of fault diagnosis,the paper proposes a fault diagnosis method of equipment based on failure rate and fault symptom.Firstly,an algorithm for calculating the equipment failure rate is proposed based on Weibull distribution model;Secondly,the probability of fault existence is evaluated based on fault symptom;Thirdly,a new fault diagnosis model is herein presented based on fault rate and fault symptom;Finally,the method is proved to be applicable through an example.The method takes failure rate,fault mechanism,fault symptom,difficulty degree of symptom acquisition and other factors into consideration,so the fault diagnosis accuracy is improved greatly.
文摘The technology of diagnostic symptom identification of nonlinear vibration is based on a database of a diagnostic case. This paper defines the periodic degree, quasi periodic degree, and chaotic degree of a Poincare map, an iterated map, and adopts the image identification theory, so the three states of periodic, quasi periodic, and chaotic running states of a machine can be distinguished. It also defines the variable identity, rotating angle and spread degree. The database of diagnostic case is expressed by means of an access database. The diagnostic symptoms are identified using the difference between the Poincare maps of samples and the fault case.Finally, we demonstrate an identification system of a nonlinear vibration diagnostic symptom of large rotating machinery.
文摘网络虚拟化环境下,底层网络的透明性造成虚拟网提供商不能诊断所有的虚拟网服务故障.为解决此问题,提出了基于映射关系的虚拟网服务故障传播模型.针对故障传播模型中故障集与症状集较大、网络环境动态和噪声大而导致的已有诊断算法误报率高、时间复杂度高的问题,基于网络虚拟化环境下症状内在相关性特点,提出了一种新的基于症状内在相关性的虚拟网服务故障诊断算法SFDoIC(service fault diagnosis algorithm based on inherent correlation among symptoms).仿真实验结果表明,SFDoIC算法能够很好地解决底层网络透明性造成的虚拟网服务故障难以定位的问题.SFDoIC算法可以有效地降低诊断算法的误报率,显著缩短诊断算法的运行时间.
