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Full-Text Articles in Engineering
Fault Diagnosis For Bearings Of Unbalanced Data Based On Feature Generation, Minglu Fan, Wang Yan, Zhicheng Ji
Fault Diagnosis For Bearings Of Unbalanced Data Based On Feature Generation, Minglu Fan, Wang Yan, Zhicheng Ji
Journal of System Simulation
Abstract: Focus on the sample imbalance and insufficiency caused by the difficulty to obtain a sufficient number of fault samples in actual production.A model for rolling bearings by combining Convolutional Neural Networks and Synthetic Oversampling is presented.The frequency domain signals is used as the input of the model,and the features are extracted by the Convolutional Neural Network.The new features are generated by Synthetic Oversampling and the data equalization is realized.The model completes the classification by putting all of the features into the Support Vector Machine,and the fault diagnosis of the rolling bearings is carried out.The comparison experiments results …
Energy Entropy And Particle Swarm Optimization Bp Neural Network Of Fault Diagnosis Techniques Of Coal Mine Cable, Zhiling Ren, Yuanyuan Zhang
Energy Entropy And Particle Swarm Optimization Bp Neural Network Of Fault Diagnosis Techniques Of Coal Mine Cable, Zhiling Ren, Yuanyuan Zhang
Journal of System Simulation
Abstract: Aimed at solving the problem of the type of fault difficult to identification when power feeder of coal mine occurred single-phase ground fault, in order to ensure coal mines production safety, a method of fault diagnosis based on wavelet packet energy entropy (WP-EE) and combined with particle swarm optimization neural network was proposed. The type of cable fault was simulated by Matlab, the acquired post-fault voltage signal was performed the three layers wavelet Packet decomposition, the fault characteristic signals was divided into eight segments by frequency, characteristics calculated the entropy energy spectrum according to the information entropy theory, …
Fault Diagnosis Of Reverse Osmosis Water Desalination Based On Optimized Support Vector Machine, Zhang Biao, Jianfeng Xing, Zhicheng Ji
Fault Diagnosis Of Reverse Osmosis Water Desalination Based On Optimized Support Vector Machine, Zhang Biao, Jianfeng Xing, Zhicheng Ji
Journal of System Simulation
Abstract: According to the reverse osmosis membrane fault problems in reverse osmosis water desalination system, a fault diagnosis method based on support vector machine (SVM) was introduced for fault diagnoses. To solve the problem of parameter optimization in SVM, an improved chaos particle swarm algorithm was proposed. The introduction of Chaos theory to particle swarm optimization algorithm may not only enhance the diversity of the population and particle global search ability, but also improve the convergence speed and accuracy of the particle swarm algorithm. The optimized SVM model was applied to the fault diagnosis of reverse osmosis water desalination system. …
Partially Observed System Design Method Realizing Unambiguous Fault Diagnosis, Fang Huan, Lu Yang, Yue Feng, Junming Guan
Partially Observed System Design Method Realizing Unambiguous Fault Diagnosis, Fang Huan, Lu Yang, Yue Feng, Junming Guan
Journal of System Simulation
Abstract: The construction methodology of partially observed system realizing unambiguous fault diagnosis was studied. The observable places determination algorithm OPD was proposed, and the necessary and sufficient condition for solution existence of the algorithm with polynomial time complexity was presented, then it is proved that all transitions in the modeled system could be distinguished by setting SO. The system operating state determination algorithm SOSD was presented based on the OPD algorithm. The proposed SOSD algorithm was realized by 1-step forward marking computation of observable places set $S_O$, it doesn't rely on the initial marking $M_0$ of the controlled …
Fault Diagnosis For Automobile Coating Equipments Based On Extension Neural Network, Yongwei Ye, Shedong Ren, Lianqiang Ye, Shenhao Ge, Zhiqin Qian
Fault Diagnosis For Automobile Coating Equipments Based On Extension Neural Network, Yongwei Ye, Shedong Ren, Lianqiang Ye, Shenhao Ge, Zhiqin Qian
Journal of System Simulation
Abstract: Aiming at the difficulty in discovering and eliminating the system faults of automobile coating equipments in time, a new method of fault diagnosis based on extension neural network was proposed. The feature of extension theory was used in managing the structured information through qualitative and quantitative description, and it was also combined by the characteristic of parallel construct in neural network. So the extension reasoning process was completed by means of the parallel distributed processing construct of the network. Matter-element input and output models were established according to the equipment monitoring parameters and fault types for the heating system. …
Research On Fault Diagnosis For Pitch Sensors Of Wind Turbines, Yanjie Zhai, Dinghui Wu, Yiyang Li, Zhicheng Ji
Research On Fault Diagnosis For Pitch Sensors Of Wind Turbines, Yanjie Zhai, Dinghui Wu, Yiyang Li, Zhicheng Ji
Journal of System Simulation
Abstract: Considering the biased output fault of pitch sensors for wind turbines, a fault diagnosis method based on the multi-innovation kalman filter algorithm was proposed. The corresponding relationship between the change of the pitch angle and the tiny displacement produced by the force acting on the tower was established according to the mechanical structure characteristics of wind turbines. More accurate estimated value for the tiny displacement was achieved by using the multi-innovation kalman filter algorithm which had higher convergence speed and estimation accuracy to reduce the large noise of the output information generated by sensors. The fault could be detected …
Application Of Pso-Bp Algorithm In Hydraulic System Fault Diagnosis, Handong Zhang, Liusong Tao
Application Of Pso-Bp Algorithm In Hydraulic System Fault Diagnosis, Handong Zhang, Liusong Tao
Journal of System Simulation
Abstract: It is of great significance to monitor, forecast and diagnose hydraulic systems’ fault timely and accurately. First, this paper describes the basic fault model theoretical knowledge of BP neural neystem failure neural network modeling has created and simulated. PSO-BP neural network has been raised, this paper has established PSO optimize model of the BP neural system fault diagnosis. BP network has been created and simulated in Plunger pump hydraulic system failure. The correct results indicate that this mixed PSO-BP algorithm is better than the improved BP algorithm, and can meet the requirements of Hydraulic system fault diagnosis.
Quick Diagnosis Of Ucav Control Surface Failure And Its Hardware-In-The-Loop Simulation, Guanhua Lu, Xia Jie
Quick Diagnosis Of Ucav Control Surface Failure And Its Hardware-In-The-Loop Simulation, Guanhua Lu, Xia Jie
Journal of System Simulation
Abstract: There are many problems in current detection methods such as conditional limitations and complexity of calculation which make them not easy to be put into practical application. The relationship between the servo motor information and the failure of the control surface was analyzed, and a method of detecting the failure rate of the control surface by using the servo current information in combination with the aerodynamic model was proposed. The result of its hardware-in-the-loop simulation shows that the detection system can quickly and accurately output the failure rate within 1 second which is a conservative estimate. That makes the …
Quick Diagnosis Of Ucav Control Surface Failure And Its Hardware-In-The-Loop Simulation, Guanhua Lu, Xia Jie
Quick Diagnosis Of Ucav Control Surface Failure And Its Hardware-In-The-Loop Simulation, Guanhua Lu, Xia Jie
Journal of System Simulation
Abstract: There are many problems in current detection methods such as conditional limitations and complexity of calculation which make them not easy to be put into practical application. The relationship between the servo motor information and the failure of the control surface was analyzed, and a method of detecting the failure rate of the control surface by using the servo current information in combination with the aerodynamic model was proposed. The result of its hardware-in-the-loop simulation shows that the detection system can quickly and accurately output the failure rate within 1 second which is a conservative estimate. That makes the …
Fault Diagnosis Algorithm Of Permanent Magnet Synchronous Motor Based On Improved Elm, Wang Xin, Wang Yan, Zhicheng Ji
Fault Diagnosis Algorithm Of Permanent Magnet Synchronous Motor Based On Improved Elm, Wang Xin, Wang Yan, Zhicheng Ji
Journal of System Simulation
Abstract: In order to address the common problems of lacking of phase and interturn short circuit fault, after analyzing the basic and corresponding fault model of permanent magnet synchronous motor(PMSM), an improved extreme learning machine (IELM) algorithm was proposed based on self-adaptive second-order particle swarm optimization (SaSECPSO). SaSECPSO employed adaptive inertia weight and cognitive coefficient with linear variation to improve the convergence rate and accuracy of second-order particle swarm optimization (SECPSO). In addition, the recognition rate of extreme learning machine (ELM) when solving the fault model of PMSM could be significantly improved by using SaSECPSO to simultaneously optimize input weights …
Improved Threshold Function Simulation Research In Vibration Signal Denoising, Hongxing Sun, Zhang Yang
Improved Threshold Function Simulation Research In Vibration Signal Denoising, Hongxing Sun, Zhang Yang
Journal of System Simulation
Abstract: Filtering noise component of mechanical vibration signal effectively can observe the characteristics of vibration signal more clearly. So based on the wavelet threshold de-noising method, a new improved threshold function was proposed. The coefficient of wavelet transform mechanical vibration signals were estimated by the threshold selection method based on kurtosis value. Not only new threshold function conforms to the distribution characteristics of the vibration signal, but also new threshold function is continuous in the threshold point. And the new threshold function overcomes the inherent deviation which traditional threshold function brings. The research of noise reduction on the simulation signal …
Fault Diagnosis Method Of Vehicle Power Supply Based On Deep Learning And Sequential Test, Li Wei, Bingxiang Zhou, Dongnian Jiang
Fault Diagnosis Method Of Vehicle Power Supply Based On Deep Learning And Sequential Test, Li Wei, Bingxiang Zhou, Dongnian Jiang
Journal of System Simulation
Abstract: Focus on the health maintenance of vehicle power supply, a fault diagnosis method of vehicle power supply is proposed, which is based on the long and short time memory LSTM(Long Short Time Memory) network and the sequential probability ratio test SPRT(Sequential Probability Ratio Test). Based on the LSTM network, the multivariate time series model of vehicle power supply is established, and the SPRT method is used to perform the adaptive multi-sample fault diagnosis. The experiment on the vehicle power supply simulation system shows that the LSTM diagnosis model has stronger learning and mapping capabilities, and the fault diagnosis method …