Search

Your search keyword '"Myung, Noh-Hoon"' showing total 151 results
Start Over Author "Myung, Noh-Hoon"
151 results on '"Myung, Noh-Hoon"'

1. Multiple scattering from two dielectric-filled semi-circular channels in a conducting plane: TM case

Author

Yu, Jong-Won, Byun, W.J., and Myung, Noh-Hoon

Subjects
Dielectrics -- Behavior, Electromagnetic waves -- Scattering, Business, Computers, Electronics, Electronics and electrical industries
Abstract

The behavior of TM-wave scattering from two dielectric-filled semi-circular channels in a perfectly conducting substrate is investigated. The scattered field is represented in terms of an infinite series of radial modes with unknown coefficients. By appling separation of variables and employing the partial orthogonality of sine functions, the unknown coefficients are obtained. The resulting infinite series is then truncated to a finite number of terms to produce numerical results. Plotted results for the radar cross sections reveal how the scattering properties may be varied by changing severial physical and geometrical parameters of the structure. Index Terms--Crack detection, electromagnetic scattering.

Published
2002

3. Robust and fast algorithm for estimating fundamental periodicity of jet engine modulation signals

Author

Park Ji Hoon, Yang Woo Yong, Song Won Young, and Myung Noh Hoon

Subjects
Engineering, business.industry, Astrophysics::High Energy Astrophysical Phenomena, 010401 analytical chemistry, Feature extraction, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Wavelet transform, 020206 networking & telecommunications, 02 engineering and technology, 01 natural sciences, Signal, 0104 chemical sciences, law.invention, Jet engine, law, Modulation, Control theory, Physics::Space Physics, 0202 electrical engineering, electronic engineering, information engineering, Electrical and Electronic Engineering, Radar, business, Algorithm, Energy (signal processing), Meyer wavelet
Abstract

Jet engine modulation (JEM), a modulation phenomenon induced by a rotating jet engine compressor, is a representative feature extracted from the radar for aircraft target recognition. In this study, the authors present a robust and fast algorithm for extracting the spool rate, which imparts fundamental periodicity to JEM signals. First, a wavelet decomposition with Meyer wavelet was applied to the analytic form of the JEM signal. Then, the decomposition components were combined to achieve a sufficient energy and minimise the mean of the JEM auto-correlation. Finally, the peak detection algorithm was employed for automatic estimation of the spool rate. Application results of measured JEM signals demonstrated that the proposed algorithm is effective for stable and accurate extraction of the jet engine information.

Published
2016

10. Automatic feature extraction from jet engine modulation signals based on an image processing method

Author

Yang Woo Yong, Kang Sung Cheol, Park Ji Hoon, Bae Jun Woo, and Myung Noh Hoon

Subjects
Engineering, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Feature extraction, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Image processing, Signal, Hilbert–Huang transform, law.invention, Jet engine, law, Feature (computer vision), RGB color model, Computer vision, Artificial intelligence, Electrical and Electronic Engineering, Radar, business
Abstract

This study presents an automatic method for extracting the jet engine features from the joint time-frequency (JTF) representation of jet engine modulation (JEM) signals. First, empirical mode decomposition with adaptive low-pass filtering was employed to extract the first harmonic component of the JEM signal. Then, a smoothed pseudo Wigner–Ville distribution (SPWVD) technique was used for acquiring the refined JTF representation. After converting the SPWVD result into an image with RGB colours, the green component was extracted as a representative of the JEM component. Finally, the peaks detected from the extracted green component can represent the jet engine features. The approach proposed in this study is significant because the overall procedures for extracting the jet engine features are not manual but automatically performed based on the image processing method. Application to measured JEM signals demonstrated that the automatic feature presented in this study improved the accuracy of JEM analysis and is expected to be efficient for real-time radar non-cooperative target recognition.

Published
2015

11. Scattering by a dielectric-loaded nonplanar slit-TM case

Author

Yu, Jong-Won and Myung, Noh-Hoon

Subjects
Electromagnetic radiation -- Research, Dielectrics -- Research, Wave propagation -- Research, Business, Computers, Electronics, Electronics and electrical industries
Abstract

An exact series solution for the problem of transverse magnetic (TM) wave scattering by a dielectric-loaded nonplanar slit is presented. Some numerical results are shown and compared with those of exact solutions. Index Terms - Electromagnetic scattering.

Published
1998

23. Oblique Scattering by a Pair of Conducting Half Planes: TM Case

Author

Yu, Jong-Won and Myung, Noh-Hoon

Subjects
Electromagnetism -- Research, Wave propagation -- Research, Electronics -- Mathematics, Business, Computers, Electronics, Electronics and electrical industries
Abstract

An exact series solution for the oblique scattering by a pair of infinitely long parallel edges of perfectly conducting half planes is formulated for a TM plane wave using the mode-matching technique (MMT). The scattered and guided fields are represented in terms of an infinite series of radial waveguide modes. By applying the appropriate boundary conditions, the coefficients of the scattered field are obtained. The diffraction coefficient of double edges is subsequently derived from the scattered field. Index Terms--Electromagnetic diffraction, mode-matching technique.

Published
1999

32. Robust and fast algorithm for estimating fundamental periodicity of jet engine modulation signals.

Author

Yang Woo Yong, Park Ji Hoon, Song Won Young, and Myung Noh Hoon

Subjects
RADAR target recognition, JET planes, RADIO frequency modulation, RADAR in aeronautics, PATTERN recognition systems, RADAR equipment
Abstract

Jet engine modulation (JEM), a modulation phenomenon induced by a rotating jet engine compressor, is a representative feature extracted from the radar for aircraft target recognition. In this study, the authors present a robust and fast algorithm for extracting the spool rate, which imparts fundamental periodicity to JEM signals. First, a wavelet decomposition with Meyer wavelet was applied to the analytic form of the JEM signal. Then, the decomposition components were combined to achieve a sufficient energy and minimise the mean of the JEM auto-correlation. Finally, the peak detection algorithm was employed for automatic estimation of the spool rate. Application results of measured JEM signals demonstrated that the proposed algorithm is effective for stable and accurate extraction of the jet engine information. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

43. TM scattering by a wedge with concaved edge

Author

Yu, Jong-Won and Myung, Noh-Hoon

Subjects
Electromagnetic waves -- Research, Wave propagation -- Research, Business, Computers, Electronics, Electronics and electrical industries
Abstract

TM scattering problem by a perfectly conducting wedge with concaved edge is formulated for a line source excitation using the mode-matching technique. The scattered and guided fields are represented in terms of an infinite series of radial waveguide modes with unknown coefficients. By applying the appropriate boundary conditions, the coefficients of scattered field are obtained. For small ka, the diffraction coefficient of concaved edge is derived from the scattered field. Index Terms - Electromagnetic scattering.

Published
1997

Catalog

Books, media, physical & digital resources
See catalog results