• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.4 no.1
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• pp.17-22
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• 2011

In this study, a P wave emphasizing and detection algorithm from ECG signal was proposed to read arrhythmia. The algorithm uses two slope tracing waveform, the descending slope tracing wave and the ascending slope tracing wave, developed for efficient determination of slope inverting points and sudden slope changing points. The algorithm generates the slope tracing waveform which trace the original ECG wave, and subtracts one tracing wave from the other to detect P and T waves. The algorithm has been applied to MIT/BIH database in order to verify its efficacy and validity in practical applications.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.215-218
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• 2011

본 논문에서는 비파괴 검사를 이용하여 획득한 세라믹 소재 영상에서 효율적으로 결함을 검출하는 방법을 제안한다. 제안된 방법은 세라믹 소재 영상에 비등방성 필터링 기법과 가우시안 필터링 기법을 반복 적용하여 잡음을 제거하고, Ends-in Search Stretching 기법을 적용하여 명암 대비를 강조한다. 명암 대비가 강조된 영상에 $7{\times}7$ Sobel 마스크를 적용하여 윤곽선을 추출한 후, 임계치 이진화 기법을 적용하여 영역을 세분화하기 위한 기울기를 계산한다. 계산된 기울기를 이용하여 영상을 세분화한 후에 Glassfire 기법을 적용한다. Glassfire 기법이 적용된 영상과 Ends-in Search Stretching 기법이 적용된 영상을 비교하여 중복되는 영역만을 추출한다. 추출된 영역에 퍼지 이진화 기법과 침식 연산을 적용하여 잡음을 제거하고 결함을 검출한다. 제안된 방법을 세라믹 소재 영상을 대상으로 실험한 결과, 기존의 결함 검출 방법보다 효율적으로 결함이 검출되는 것을 확인할 수 있었다.

• 한국도로학회:학술대회논문집
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• 2002.10a
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• pp.195-198
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• 2002

• Journal of Digital Contents Society
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• v.18 no.5
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• pp.989-994
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• 2017

In this paper, we propose a pothole detection system using 2D LiDAR and a pothole detection algorithm. Conventional pothole detection methods can be divided into vibration-based method, 3D reconstruction method, and vision-based method. Proposed pothole detection system uses two inexpensive 2D LiDARs and improves pothole detection performance. Pothole detection algorithm is divided into preprocessing for noise reduction, clustering and line extraction for visualization, and gradient function for pothole decision. By using gradient of distance data function, we check the existence of a pothole and measure the depth and width of the pothole. The pothole detection system is developed using two LiDARs, and the 3D pothole detection performance is shown by detecting a pothole with moving LiDAR system.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.2
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• pp.33-38
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• 2008

The baseline wander of ECG makes difficult to detect P-, Q-, R- and S-wave. This paper presents and compares two method to remove the baseline wander of ECG using slope traceing waves. For the first method that had been proposed already[1], the ascending slope tracing method is used to eliminate baseline wander. And the second method employs the contour of the approximated S-wave to remove baseline wander. These two methods are common to use the slope tracing wave. However, the first one is to get difference signals between the ascending tracing waves and ECG signals, and the other is to remove baseline wander using the contour of the approximated S-wave obtained from descending slope waves. To evaluate these methods, we apply to MIT/BIH database.

• Journal of Korea Multimedia Society
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• v.9 no.4
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• pp.470-481
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• 2006

In this paper, we propose a real-time face detection, tracking and tilted face image correction system using multi-color model and face feature information. In the proposed system, we detect face candidate using YCbCr and YIQ color model. And also, we detect face using vertical and horizontal projection method and track people's face using Hausdorff matching method. And also, we correct tilted face with the correction of tilted eye features. The experiments have been performed for 110 test images and shows good performance. Experimental results show that the proposed algorithm robust to detection and tracking of face at real-time with the change of exterior condition and recognition of tilted face. Accordingly face detection and tilted face correction rate displayed 92.27% and 92.70% respectively and proposed algorithm shows 90.0% successive recognition rate.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.121-128
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• 2008

Accurate voice activity detection have a great impact on performance of speech applications including speech recognition, speech coding, and speech communication. In this paper, we propose methods for voice activity detection that can adapt to various car noise situations during driving. Existing voice activity detection used various method such as time energy, frequency energy, zero crossing rate, and spectral entropy that have a weak point of rapid. decline performance in noisy environments. In this paper, the approach is based on existing spectral entropy for VAD that we propose voice activity detection method using MFB(Met-frequency filter banks) spectral entropy, gradient FFT(Fast Fourier Transform) spectral entropy. and gradient MFB spectral entropy. FFT multiplied by Mel-scale is MFB and Mel-scale is non linear scale when human sound perception reflects characteristic of speech. Proposed MFB spectral entropy method clearly improve the ability to discriminate between speech and non-speech for various in noisy car environments that achieves 93.21% accuracy as a result of experiments. Compared to the spectral entropy method, the proposed voice activity detection gives an average improvement in the correct detection rate of more than 3.2%.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.35-37
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• 2005

In this study, a P- and T-wave detection algorithm in ECG, obtained by minimized filtering to prevent waveform distortion, has been realized. The algorithm uses two slope tracing waves, the descending slope tracing wave and the ascending slope tracing wave, developed for efficient determination of slope inverting points and sudden slope changing points. The algorithm generates the slope tracing waves which trace the original ECG wave, and subtracts one tracing wave from the other to detect P- and T-waves. The algorithm has been applied to MIT/BIH database in order to verify its efficacy and validity in practical applications.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.517-519
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• 2001

본 논문에서는 신원 확인 시스템을 위한 얼굴 영역 탐지 및 얼굴 구성 요소들을 추출하는 방법을 제안한다. 이 방법은 신원 확인을 위해 사용자가 시스템을 조작할 때, 움직임이 발생한다는 점과 눈 영역이 주위 영역에 비하여 뚜렷하게 어두운 화소들로 구성되어 있다는 점에 착안하였다. CCD 카메라로부터 입력되는 동영상에서 차영상 기법을 이용하여 얼굴 영역을 탐지하고, 탐지된 얼굴 영역 내에서 가장 안정적인 검출 결과를 보이는 눈 영역을 추출한다. 그리고 추출된 두 눈의 위치를 이용하여 전체 얼굴의 기울기를 보정한 수, 제안하는 가변 Ratio Template을 이용하여 검출된 얼굴영역을 검증하며 코, 입과 같은 다른 얼굴 구성 요소들을 추출한다. 이 방법은 명암의 변화에 따라 유동적인 결과를 산출해내는 이진화 과정을 거치지 않으므로 국부적인 조명이 밝기 변화나 얼굴의 기울기 변화와 같은 얼굴 인식의 제약점에 강인한 특징을 가진다.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.946-949
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• 2004

It is necessary to detect the tilt angle for control or monitoring of various systems such as ship, aircraft recreation facilities etc as well as bridge or building systems. However the electronic liquid charge type tilt sensor which is one of typical tilt sensor has many problems. Those are remarkably slow response time and limited mounting condition because or liquid viscosity coefficient and inertia etc. In this study we propose a tilt angle instrumentation method using piezoelectricity acceleration sensor. The method can he applied on moving mount We verified the validity of the method through experiment.