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Kim, Jae-Joon
- Journal of the Korean Society for Nondestructive Testing
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- v.24 no.6
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- pp.590-596
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- 2004
Neural network-based signal classification systems are increasingly used in the analysis of large volumes of data obtained in NDE applications. Ultrasonic inspection methods on the other hand are commonly used in the nondestructive evaluation of welds to detect flaws. An important characteristic of ultrasonic inspection is the ability to identify the type of discontinuity that gives rise to a peculiar signal. Standard techniques rely on differences in individual A-scans to classify the signals. This paper proposes an ultrasonic signal classification technique based on the information tying in the neighboring signals. The approach is based on a 2-dimensional Fourier transform and the principal component analysis to generate a reduced dimensional feature vector for classification. Results of applying the technique to data obtained from the inspection of actual steel welds are presented.
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Kwun, He-Geon;Kim, Sang-Young;Light, Glenn M.
- Journal of the Korean Society for Nondestructive Testing
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- v.21 no.4
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- pp.383-390
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- 2001
Long-range guided wave inspection is a new emerging technology for rapidly and globally inspecting a large area of a structure from a single test location. This paper describes a general overview of the guided wave properties and its application for long-range inspection of structures the principle and instrument system for a guided wave inspection technology called "magnetostrictive sensor (MsS)" that generates and detects guided waves electromagnetically in the material under testing, and examples of long-range guided wave inspection of structures that can be accomplished using the MsS.
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Kim, J.K.;Koh, S.N.;Kim, M.K.;Shim, Y.J.
- Journal of the Korean Society for Nondestructive Testing
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- v.18 no.1
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- pp.27-32
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- 1998
This paper is written to introduce a multimedia tutoring system for nondestructive testing using personal computer. Nondestructive testing, one of the chief methods for inspecting welds and many other components, is very difficult for the NDT inspectors to understand its technical basis without a wide experience. And it is necessary for considerable repeated education and training for keeping their knowledge. The tutoring system that can simulate NDT works is suggested to solve the above problem based on reasonable condition. The tutoring system shows basic theories of nondestructive testing in a book-style with video images and hyper-links, and it offers practices, in which users can simulate the testing equipment. The book-style and simulation practices provide effective and individual environments for learning nondestructive testing.
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