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Process of Building Artificial Neural Network for Automatic Detection of Signals from Transverse Cracks in the Rail Head

Nichoga V., Prudyus I., Vashchyshyn L.

Problemy Kolejnictwa

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2017

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Z. 175

59--62

EN

In this article the process of building artificial neural network (ANN) for automatic detection signals from transverse cracks in the rail head is described. Selection details and real signal samples (for ANN training) are also presented.

PL

Artykuł opisuje proces projektowania sztucznej sieci neuronowej (ANN) do automatycznego wykrywania sygnałów z pęknięć poprzecznych w główce szyny kolejowej. Do celów szkoleniowych w zakresie ANN przedstawiono również szczegóły dotyczące wyboru próbki i rzeczywiste próbki sygnału.

2

Application of the wavelet and neural technologies for processing of signals obtained during railway tracks diagnostics by the magnetic flux leakage method

Nichoga V., Vashchyshyn L.

Biuletyn Wojskowej Akademii Technicznej

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2017

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Vol. 66, nr 4

195--201

EN

In this article, the approach for detecting a transverse crack in the rail head via ANN with CWT and application created on its basis are presented. The ways of further development of the ANN for improving its work accuracy and the possibility of identification of other types of defects are also presented.

PL

W artykule rozpatrzono sposób ujawnienia poprzecznego pęknięcia w głowicy szyny kolejowej metodą ciągłej transformacji falkowej (CTF) oraz metodą sztucznej sieci neuronowej (SSN). Przedstawiono program stosowany do analizy sygnałów defektoskopijnych. Zaproponowano sposoby dalszego rozwoju SSN w celu poprawy dokładności jego pracy i możliwości zidentyfikowania innych rodzajów wad.

3

Numerical investigation of a response of the rotor KJT4 (RK4) with a fatigue crack excited by centrifugal forces due to the disk unbalance

Ferfecki P., Ondrouch J.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 31

11-14

EN

A method of computational modelling is applicd for invcstigation of influence of transverse fatigue crack located in the midspan of rotor system RK 4. The response of rotor system RK 4 is computed from equations of motion derived in the rotor-fixed co-ordinate system utilizing the Runge-Kutta method of the 4th order. The influence of the crack in rotor system is investigated by means of frequency spectra obtained from time domain response.

4

Progressive failure modelling of transverse cracking in cross-ply laminates with double-edge-semicircular notches

Liu C. J., Nijhof A. H. J., Ernst L. J., Marissen R.

Engineering Transactions

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2002

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Vol.50, iss.4

287-303

EN

A local-global progressive failure finite element (FEM) model was created in combination with the maximum strain criterion on an individual layer scale to study the formation of transverse cracks in cross-ply laminates with double-edge-semicircular notches. It is assumed that the laminate is made of homogeneous orthotropic layers before the occurrence of the matrix failure. Then, the average reduced layer stiffness as a function of the applied load is separated from the reduced laminate stiffness. Additionally, a maximum strain strength criterion is applied on a very local scale of a single layer to induce the local matrix failure. The initiation, propagation and multiplication of the transverse cracks starting from the notch are predicted in this way. The influences of the laminar thickness and the notch-width aspect ratios were also studied. Furthermore, the stress distribution and redistribution caused by the initiation and propagation of the transverse cracks were calculated. In addition to the stress concentration caused by the circular notch, an extra stress concentration in the 0° layers is induced by the transverse cracks in the 90° layers. This stress redistribution will in turn initiate more local failures in the 0° layers or at the interface between the longitudinal and transverse layers. The simulated results show a good agreement with experimental observations.