A new algorithm was developed to correctly identify fault conditions and accurately monitor fault development in a mine hoist. The new method is based on the Wavelet Packet Transform (WPT) and kernel PCA (Kernel Princ...A new algorithm was developed to correctly identify fault conditions and accurately monitor fault development in a mine hoist. The new method is based on the Wavelet Packet Transform (WPT) and kernel PCA (Kernel Principal Compo- nent Analysis, KPCA). For non-linear monitoring systems the key to fault detection is the extracting of main features. The wavelet packet transform is a novel technique of signal processing that possesses excellent characteristics of time-frequency localization. It is suitable for analysing time-varying or transient signals. KPCA maps the original input features into a higher dimension feature space through a non-linear mapping. The principal components are then found in the higher dimen- sion feature space. The KPCA transformation was applied to extracting the main nonlinear features from experimental fault feature data after wavelet packet transformation. The results show that the proposed method affords credible fault detection and identification.展开更多
With the expansion and increasing complexity of data center networks(DCNs),network fault-tolerance has become increasingly important.RRect is a server-centered DCN with a good interconnection structure.In this paper,w...With the expansion and increasing complexity of data center networks(DCNs),network fault-tolerance has become increasingly important.RRect is a server-centered DCN with a good interconnection structure.In this paper,we propose a fault-tolerant routing algorithm RRFP under a conditional fault pattern of RRect,which can find a fault-free path between any two fault-free vertices.Firstly,we study a fault pattern of RRect in the case of restricted faulty vertex sets,{1,2}-restricted connectivity.It is about{2,3}times RRect’s traditional connectivity,indicating that{1,2}-restricted connectivity better evaluates the fault-tolerant capability.Secondly,we design an effective fault-tolerant routing algorithm RRFP under the conditional fault pattern of RRect,and RRFP can accommodate more faulty vertices.Finally,we conduct experiments on RRFP to evaluate its performance.The experimental results show that in terms of the running time,as parameters n and k change,RRFP outperforms Dijkstra’s algorithm by 64%–84%and Breadth-First-Search(BFS)by 56%–71%.The running time of all the three algorithms is very short as parameter m changes.In terms of the constructing path length,as parameters change,RRFP outperforms BFS by 12%–19%.Moreover,the path constructed by RRFP approaches the shortest path of Dijkstra’s algorithm.Moreover,RRFP still maintains a low transmission failure rate(TFR)and high reliability even with an increase in the number of fault elements.展开更多
针对容错模式下的统一电能质量调节器(Unified Power Quality Conditioner,UPQC),提出了一种五桥臂形式的新型拓扑结构,实现故障下的电能质量扰动综合补偿。在此基础上,对串联变流器和并联变流器进行统一建模,提出了一种基于有限集模型...针对容错模式下的统一电能质量调节器(Unified Power Quality Conditioner,UPQC),提出了一种五桥臂形式的新型拓扑结构,实现故障下的电能质量扰动综合补偿。在此基础上,对串联变流器和并联变流器进行统一建模,提出了一种基于有限集模型预测控制(Finite Control Set Model Predictive Control,FCS-MPC)的五桥臂UPQC控制策略。相比传统线性控制策略,所提算法构建了统一的预测模型以及整合优化的价值函数,实现串联变流器与并联变流器的协同控制,提高了两侧变流器的补偿精度、暂态性能以及响应速度,有效降低了控制算法的复杂度和参数调节难度,并具有较高的参数鲁棒性。仿真结果验证了所提算法的可行性和有效性。展开更多
基金Projects 50674086 supported by the National Natural Science Foundation of ChinaBS2006002 by the Society Development Science and Technology Planof Jiangsu Province20060290508 by the Doctoral Foundation of Ministry of Education of China
文摘A new algorithm was developed to correctly identify fault conditions and accurately monitor fault development in a mine hoist. The new method is based on the Wavelet Packet Transform (WPT) and kernel PCA (Kernel Principal Compo- nent Analysis, KPCA). For non-linear monitoring systems the key to fault detection is the extracting of main features. The wavelet packet transform is a novel technique of signal processing that possesses excellent characteristics of time-frequency localization. It is suitable for analysing time-varying or transient signals. KPCA maps the original input features into a higher dimension feature space through a non-linear mapping. The principal components are then found in the higher dimen- sion feature space. The KPCA transformation was applied to extracting the main nonlinear features from experimental fault feature data after wavelet packet transformation. The results show that the proposed method affords credible fault detection and identification.
基金supported by the National Natural Science Fund for Distinguished Young Scholars of China under Grant No.62125203the National Natural Science Foundation of China under Grant Nos.61932013,62102196,62372248,and 62302235+1 种基金the Natural Science Fund for Colleges and Universities in Jiangsu Province of China under Grant No.24KJA520006the Postgraduate Research and Practice Innovation Program of Jiangsu Province of China under Grant No.SJCX23_0275.
文摘With the expansion and increasing complexity of data center networks(DCNs),network fault-tolerance has become increasingly important.RRect is a server-centered DCN with a good interconnection structure.In this paper,we propose a fault-tolerant routing algorithm RRFP under a conditional fault pattern of RRect,which can find a fault-free path between any two fault-free vertices.Firstly,we study a fault pattern of RRect in the case of restricted faulty vertex sets,{1,2}-restricted connectivity.It is about{2,3}times RRect’s traditional connectivity,indicating that{1,2}-restricted connectivity better evaluates the fault-tolerant capability.Secondly,we design an effective fault-tolerant routing algorithm RRFP under the conditional fault pattern of RRect,and RRFP can accommodate more faulty vertices.Finally,we conduct experiments on RRFP to evaluate its performance.The experimental results show that in terms of the running time,as parameters n and k change,RRFP outperforms Dijkstra’s algorithm by 64%–84%and Breadth-First-Search(BFS)by 56%–71%.The running time of all the three algorithms is very short as parameter m changes.In terms of the constructing path length,as parameters change,RRFP outperforms BFS by 12%–19%.Moreover,the path constructed by RRFP approaches the shortest path of Dijkstra’s algorithm.Moreover,RRFP still maintains a low transmission failure rate(TFR)and high reliability even with an increase in the number of fault elements.
文摘针对容错模式下的统一电能质量调节器(Unified Power Quality Conditioner,UPQC),提出了一种五桥臂形式的新型拓扑结构,实现故障下的电能质量扰动综合补偿。在此基础上,对串联变流器和并联变流器进行统一建模,提出了一种基于有限集模型预测控制(Finite Control Set Model Predictive Control,FCS-MPC)的五桥臂UPQC控制策略。相比传统线性控制策略,所提算法构建了统一的预测模型以及整合优化的价值函数,实现串联变流器与并联变流器的协同控制,提高了两侧变流器的补偿精度、暂态性能以及响应速度,有效降低了控制算法的复杂度和参数调节难度,并具有较高的参数鲁棒性。仿真结果验证了所提算法的可行性和有效性。