• Journal of the Korean Society of Safety
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• v.16 no.3
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• pp.135-142
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• 2001

This study discusses frequency analysis based on the frequency spectrum and process characterization in orthogonal cutting of Fiber-matrix composite materials. A sparsely distributed idealized composite material, namely a glass reinforced polyester(GFRP) was used as workpiece The present method employs a force sensor and the signals from the sensor are processed using the fast Fourier transform(FFT) technique. The experimental correlations between the different chip formation mechanisms and power spectrum me established. Effects of fiber orientation, cutting parameters and tool geometry on the cutting mechanisms me also discussed.

• The Korean Publising Journal, Monthly
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• s.224
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• pp.10-11
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• 1997

현대사회에서 디자인은 삶을 재해석하는 중요한 문화현상이다. 최근 디자인이 미래 문화의 중핵으로 작용할 것이라는 전망 아래, 다양한 스팩트럼으로 디자인의 세계를 조명한 진지한 책들이 활발하다.

• Korean Architects
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• no.8 s.400
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• pp.46-53
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• 2002

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1992.06a
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• pp.343-346
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• 1992

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1992.06a
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• pp.545-548
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• 1992

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1992.10a
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• pp.292-295
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• 1992

• Information Display
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• v.15 no.1
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• pp.32-40
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• 2014

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.353-358
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• 2004

A transient irregular wave was designed based on ISSC spectrum The designed wave was generated in the towing tank and ,the roll motion of a model was measured A method to predict the maximum roll motion, expected in the short-term sea state, was investigated with comparison of the theoretical and experimental results.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.19 no.2
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• pp.101-106
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• 2008

The speech signal has been put into a form suitable for storage and analysis by computer, several different operation can be performed. Filtering, sampling and quantization are the basic operation in digiting a speech signal. The waveform can be displayed, measured and even edited, and spectra can be computed using methods such as the Fast Fourier Transform (FFT), Linear predictive Coding (LPC), Cepstrum and filtering. The digitized signal also can be used to generate spectrograms. The spectrograph provide major advantages to the study of speech. So, author introduces the basic techniques for the acoustic recording, digital signal processing and the principles of spectrum and spectrogram.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.4
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• pp.53-66
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• 1990

Rainfall is a phenomenon that shows a high variability both in space and time, Hy drologists are usually interested in the description of spatial distribution of rainfall over watershed. The theory of Kriging, generalized covariance technique using nonstationary mean in the regions under orographic effect, was chosen to construct random surface of total storm depth. For the constructed random surface, the double Fourier analysis of the total storm depths was performed, and the principal harmonics of storm were determined. The local component, or storm residuals was obtained by subtracting the periodic component of the storm from total storm depths. It is assumed that the residuals are a sample function of a homogeneous random field. This random field can be characterized by an isotropic one dimensional autocorrelation function or its corresponding spectral density function. Under this assumption, this study proposed a theorectical model for spectral density function adapted to two watersheds.