• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.3
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• pp.69-78
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• 1996

This paper presetns an iterative relaxation method for stereo matching using matching probability and compatibility coefficients between disparities. Stereo matching can be considered as the labeling problem of assigning unique matches to feature points of image an relaxation labelin gis an iterative procedure which reduces local ambiguities and achieves global consistency. the relation between disparities is determined from highly reliable matches in initial matching and quantitatively expressed in temrs of compatibility coefficient. The matching results of neighbor pixels support center pixel through compatibility coefficients and update its matching probability. The proposed adaptive method reduces the degradtons on the discontinuities of disparity areas and obtains fast convergence.

• Communications for Statistical Applications and Methods
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• v.14 no.1
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• pp.241-254
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• 2007

This paper propose a new short-term interest rate model having a different nonlinear drift function and the same diffusion coefficient with Chan et al. (1992) model. The fractional polynomial power of the drift function in our model is linked to the local volatility elasticity of the diffusion coefficient. While the nonlinear drift function estimated by $A\"{\i}t$-Sahalia (1996a) and others has a feature that higher interest rates tend to revert downward and low rates upward, the drift function estimated by our nonlinear model shows that higher interest rate mean-reverts strongly, but, medium rates has almost zero drift and low rates has a very small drift. This characteristic coincides the empirical result based on the nonparametric methodology by Stanton (1997) and the implication by the scatter plot of the short rate data.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.143-146
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• 2007

객체의 특징점을 추출할 때, 일반적으로 모델 기반 접근을 사용한다. 본 논문에서는 이러한 모델 기반 특징점 추출 알고리즘으로 PCA를 근간으로 하는 Active Appearance Model을 이용하는데, 기존의 AAM 알고리즘은 모든 특징점을 하나의 군집으로 기준하여 PCA를 수행하지만 본 논문에서는 이것을 각 주요 부위별 학습 모델로 분리하여 수행한다. 그리고 이러한 모델에서 특징점을 찾을 때, 발산하는 문제에 빠지지 않기 위한 방법을 제시한다. 제시한 방법의 모델을 이용하여 실험 할 경우의 결과와 이를 통한 개별 모델의 특성에 대하여 파악한 결과를 제시한다.

• Applied Microscopy
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• v.42 no.3
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• pp.164-173
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• 2012

The relaxor ferroelectric feature in lead-free perovskite oxides, where the dipoles are randomly oriented and they can be feasibly aligned parallel to the external bias, is attracting lots of attention in the field of piezoelectric materials science, since it is one of candidates to replace the toxic lead-based materials that are still being commercially used. However, the origin of relaxor characteristic and its related atomic structure are still ambiguous. In this study, $Na_{1/2}Bi_{1/2}TiO_3$, chosen as a model relaxor system, was found to exhibit a cationic-disordered atomic structure; and furthermore the nonpolar atomic structure and its related oxygen tilting were ascertained via annular bright field imaging skill. We also found that this cationic disordering gives rise to the local formation of atomic vacancies.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2016.06a
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• pp.194-197
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• 2016

자동차 산업이 발전하면서 안정적인 주행과 운전자의 편의성을 위한 지능형운전자보조시스템인 ADAS (Advanced Driver Assistance System)가 이슈가 되고 있다. 차선인식의 결과에 따라 차선이탈 경고시스템의 성능이 달라지기 때문에 차선인식은 ADAS에서 매우 중요한 핵심적인 기술이라 할 수 있다. 이에 본 논문에서는 그림자 영역과 같이 밝기의 분포가 균일하지 않는 환경에서 강인하게 동작하는 차선인식 알고리즘을 제안하였다, 지역적인 밝기 특징을 고려하여 차선에 해당하는 특징점을 추출하며, 추출된 특징점 가운데 이상치(outlier)를 제거하기 위해 RANSAC (RANdom SAmple Consensus) 알고리즘을 이용하여 차선을 검출한다. 또한 RANSAC 알고리즘에서 신뢰도가 높은 차선이 검출되면 그 주위에 특징점을 추출하기 위한 관심영역을 설정함으로써 안정적인 차선 검출이 가능하도록 하였다.

• The Journal of the Korea Contents Association
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• v.3 no.1
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• pp.58-63
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• 2003

In this paper, an object tracking system in a known environment is proposed. It extracts moving area shaped on objects in video sequences and decides tracks of moving objects. Color invarianoe features are exploited to extract the plausible object blocks and the degree of radial homogeneity, which is utilized as local block feature to find out the block correspondences. The experimental results are given.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.260-261
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• 2008

이동 물체 탐지(Object Detection) 기법은 대부분의 감시 시스템에서 가장 초기 단계로서, 이후에 물체 추적(Object Tracking) 및 물체 식별(Object Classification) 등의 지능 알고리듬에 입력으로 사용된다. 따라서 물체의 윤곽의 변화 없이 최대한 정교하게 이동 물체 영역 맵을 생성하는 것이 물체 탐지의 가장 중요한 요소가 된다. 카메라가 고정되어 있는 경우에는 현재 들어오는 영상에 대한 확률적 배경 모델을 생성할 수 있지만, 팬틸트 카메라와 같이 영상의 좌표가 변하는 환경에서는 배경 모델도 계속 변하기 때문에 기존의 배경 모델을 그대로 사용할 수 없다. 본 논문에서는 팬틸트 카메라와 같이 동적인 카메라에서 이동 물체 탐지를 위해, 국소 특징점(Local Feature)를 통해 카메라의 움직임을 판단하여 연속되는 영상간의 변환 행렬(Transformation Matrix)를 구하고 하고, 확률적 배경 모델링을 통한 이동 물체 탐지 기법을 제안한다. 자제 촬영한 이동 카메라 실험영상을 통해서 이 알고리듬이 동적 배경에서도 매우 강인하게 동작하는 것을 검증하였다.

• Journal of Korean Neurosurgical Society
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• v.53 no.2
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• pp.121-124
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• 2013

Granular cell tumors (GrCTs) of the spinal cord are rare benign tumors with a high rate of local recurrence. Only 6 cases of spinal GrCTs have been reported. GrCT is difficult to distinguish from other benign tumors such as schwannoma using imaging. A radiological "speckled dots" sign may be a useful differentiating feature of GrCT based upon experience with two cases and a review of the literature.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.5
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• pp.510-516
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• 2015

This paper describes an approach to detect interesting objects using satellite images. This paper focuses on the interesting objects that have common special patterns but do not have identical shapes and sizes. The previous technologies are still insufficient for automatic finding of the interesting objects based on operation of special pattern analysis. In order to overcome the circumstances, this paper proposes a methodology to obtain the special patterns of interesting objects considering their common features and their related characteristics. This paper applies MSER(Maximally Stable Extremal Regions) for the region detection and corner detector in order to extract the features of the interesting object. This paper conducts a case study and obtains the experimental results of the case study, which is efficient in reducing processing time and efforts comparing to the previous manual searching.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.617-622
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• 2002

This paper presents that the Wavelet Transform can be used to detect the various local defects in a gearbos. Two types of defects which are broken tooth and localized wear, are experimented and the signals are collected by accerometer and analyzed. Because of the complecity of the signals acquired from sensor, it is needed to identify the interesting signal. The natural frequencies of shafts and the gear mesh frequency(GMF) is calculated theretically. DWT, CWT and the aplication are used to extract a gear-localized defect feature from the vibration signal of the gearbox with the defective gear. The results shows the transform is more effective to detect the failures than the Fourier Transform.