In order to diagnose the common faults of railway switch control circuit,a fault diagnosis method based on density-based spatial clustering of applications with noise(DBSCAN)and self-organizing feature map(SOM)is prop...In order to diagnose the common faults of railway switch control circuit,a fault diagnosis method based on density-based spatial clustering of applications with noise(DBSCAN)and self-organizing feature map(SOM)is proposed.Firstly,the three-phase current curve of the switch machine recorded by the micro-computer monitoring system is dealt with segmentally and then the feature parameters of the three-phase current are calculated according to the action principle of the switch machine.Due to the high dimension of initial features,the DBSCAN algorithm is used to separate the sensitive features of fault diagnosis and construct the diagnostic sensitive feature set.Then,the particle swarm optimization(PSO)algorithm is used to adjust the weight of SOM network to modify the rules to avoid“dead neurons”.Finally,the PSO-SOM network fault classifier is designed to complete the classification and diagnosis of the samples to be tested.The experimental results show that this method can judge the fault mode of switch control circuit with less training samples,and the accuracy of fault diagnosis is higher than that of traditional SOM network.展开更多
There are two algebraic lower bounds of the number of n-periodic points of a self-map f : M →4 M of a compact smooth manifold of dimension at least 3: NFn(f) = min{#Fix(gn);g - f; g continuous} and NJDn(f) = ...There are two algebraic lower bounds of the number of n-periodic points of a self-map f : M →4 M of a compact smooth manifold of dimension at least 3: NFn(f) = min{#Fix(gn);g - f; g continuous} and NJDn(f) = min{#Fix(gn);g - f; g smooth}. In general, NJDn(f) may be much greater than NFn(f). We show that for a self-map of a semi-simple Lie group, inducing the identity fundamental group homomorphism, the equality NFn(f) = NJDn(f) holds for all n →← all eigenvalues of a quotient cohomology homomorphism induced by f have moduli ≤ 1.展开更多
Let A be a unital C-algebra, n ∈ N ∪ {∞}. It is proved that the isomorphism △n : is isometric for some suitable distances. Asan application, the author has the split exact sequence with iA contractive (and isometr...Let A be a unital C-algebra, n ∈ N ∪ {∞}. It is proved that the isomorphism △n : is isometric for some suitable distances. Asan application, the author has the split exact sequence with iA contractive (and isometric if n = ∞) under certain condition of A.展开更多
基金High Education Research Project Funding(No.2018C-11)Natural Science Fund of Gansu Province(Nos.18JR3RA107,1610RJYA034)Key Research and Development Program of Gansu Province(No.17YF1WA 158)。
文摘In order to diagnose the common faults of railway switch control circuit,a fault diagnosis method based on density-based spatial clustering of applications with noise(DBSCAN)and self-organizing feature map(SOM)is proposed.Firstly,the three-phase current curve of the switch machine recorded by the micro-computer monitoring system is dealt with segmentally and then the feature parameters of the three-phase current are calculated according to the action principle of the switch machine.Due to the high dimension of initial features,the DBSCAN algorithm is used to separate the sensitive features of fault diagnosis and construct the diagnostic sensitive feature set.Then,the particle swarm optimization(PSO)algorithm is used to adjust the weight of SOM network to modify the rules to avoid“dead neurons”.Finally,the PSO-SOM network fault classifier is designed to complete the classification and diagnosis of the samples to be tested.The experimental results show that this method can judge the fault mode of switch control circuit with less training samples,and the accuracy of fault diagnosis is higher than that of traditional SOM network.
基金supported by the National Science Center,Poland(Grant No.UMO2014/15/B/ST1/01710)
文摘There are two algebraic lower bounds of the number of n-periodic points of a self-map f : M →4 M of a compact smooth manifold of dimension at least 3: NFn(f) = min{#Fix(gn);g - f; g continuous} and NJDn(f) = min{#Fix(gn);g - f; g smooth}. In general, NJDn(f) may be much greater than NFn(f). We show that for a self-map of a semi-simple Lie group, inducing the identity fundamental group homomorphism, the equality NFn(f) = NJDn(f) holds for all n →← all eigenvalues of a quotient cohomology homomorphism induced by f have moduli ≤ 1.
基金Project supported by the National Natural Science Foundation of China (No.10271090).
文摘Let A be a unital C-algebra, n ∈ N ∪ {∞}. It is proved that the isomorphism △n : is isometric for some suitable distances. Asan application, the author has the split exact sequence with iA contractive (and isometric if n = ∞) under certain condition of A.