ANALYSIS OF RAIL DEFECTS SIGNALS BY THE MATLAB WAVELET TOOLBOX PROGRAMME
Journal Title: Вісник Національного університету "Львівська політехніка", серія "Радіоелектроніка та телекомунікації" - Year 2014, Vol 796, Issue 2014
Abstract
Rail networks across the world are getting busier with trains travelling at higher speeds and carrying more passengers and heavier axle loads than ever before. The combination of these factors has put considerable pressure on the existing infrastructure, leading to increased demands in inspection and maintenance of rail assets [1]. Nowadays, rails are systematically inspected for internal and surface defects using various nondestructive evaluation (NDE) techniques. The most common of which are ultrasonic and magnetic flux leakage (MFL) methods. The article is focused on the analysis of defectoscopic signals received using the magnetic wagon-defectoscope of Lviv Railway (MFL method) by the continuous wavelet transform (CWT). The most important question in all methods NDE - is selection of information about defects from defectoscopic signals received during the checking railway (defectogram). At present, wagon-defectoscope operator’s experience is essential for making the correct decision about technical condition of rails. To improve the operator’s work efficiency, which is mainly based on expert visual assessments, it is necessary to automate the analysis9 of recorded signals. That is why we turned to the powerful tool of digital signal processing such as wavelet transform (WT). The main WT applications - analysis and processing signals, non-stationary in time (such as defectoscopic signals) when the analysis should include not only the signal frequency characteristics, but also information about some local coordinates, which reveal themselves in one or other frequency components. WT divides into continuous (CWT) and discrete (DWT). DWT focuses on speed (by sampling values of scale (frequency) and time (samples)) and the possibility of a complete reconstruction of the signal after analysis (by orthogonal wavelet functions), which led to its use, mostly for denoising and compression of signals. As for CWT, it requires only one wavelet function - mother, whose creation is not problematical (unlike DWT) and allows to identify those signals that are similar to the mother wavelet.
Authors and Affiliations
Vitaliy Nichoha, Liubomyr Vashchyshyn, O. Saldan
Keywords
Related Articles
- EP ID EP459701
- DOI -
- Views 142
- Downloads 0
STUDY OF THE LOAD MANAGEMENT MECHANISMS IN CONTENT DELIVERY NETWORKS
Concept content delivery network (CDN) system and load balancing mechanisms were considered in this paper. The main task of the CND network - providing the qualitative information delivery to the end user. Content Delive...
INVESTIGATION OF CONTROL PLANE IN SOFTWARE-DEFINED NETWORKS BASED ON DISTRIBUTED SYSTEM OF VIRTUALIZATION FUNCTIONS
In this paper are proposed the number of solutions for improvement of control plane in software-defined networks. One of the main problems that arise when designing and implementing new network is the problem of developi...
THE PROCEDURE OF OPTIMIZATION OF LINEAR PERIODICALLY TIME-VARIABLE CIRCUITS IN AN ENVIRONMENT UDF MAOPCs
The paper presents the procedure of optimization of linear periodically time-variable circuits based on the calculation of circuit parametric transfer functions by the frequency symbolic method. The parametric transfer f...
ESTIMATING THE ADEQUACY OF SOFTWARE ROUTER PERFORMANCE UNDER MULTIMEDIA TRAFFIC PROCESSING
In this paper we perform a study of probabilistic and statistical properties of experimental traffic of multiservice telecommunication network to confirm the adequacy of the developed software router model and simulated...
CHANNEL SELECTION ALGORITHMS PERFORMANCE EVALUATION FOR SPECTRUM DECISION IN COGNITIVE RADIO
Different spectrum decision methods in a Cognitive radio network were analyzed in this paper. The technology of Cognitive Radio networks needs to make a decision which spectrum band is the best among the available free b...