• Journal of Korean Society for Geospatial Information Science
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• v.16 no.4
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• pp.79-87
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• 2008

There has been a strong demand for low altitude UAV development in rapid mapping not only to acquire high resolution image with much more low cost and weather independent, compared to satellite surveying or traditional aerial surveying, but also to meet many needs of the aerial photogrammetry. Especially, efficient geocoding of UAV imagery is the key issue. Contrary to high UAV potential for civilian applications, the technology development in photogrammetry for example direct georeferencing is in the early stage and it requires further research and additional technical development. In this study, two approaches are supposed for automatic geocoding of UAV still images by simple affine transformation and block adjustment of affine transformation using minimal ground control points and also evaluated the applicability and quality of geometric model compared to geocoded images generated by commercial S/W.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.5
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• pp.471-478
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• 2016

This paper proposes the results of analysis of correlation between satellite geometry elements for an effective use of satellite images. To achieve accurate positional information, stereo images have normal range of convergence and BIE (BIsector Elevation) angles which are greatly influenced by azimuth and elevation angle of individual image. In this paper, the variations of convergence and BIE angles are estimated according to azimuth angle differences between two images and each elevation angle. The analysis provided strong support for predicting stereo geometry without complex analysis of epiploar geometry or mathematics. The experiment results showed that more than 150°, 130°, and 100° azimuth angle differences need to be constructed when elevation angle of two images is 50°, 60°, and 70°, respectively, in order to make the convergence and BIE angle within normal range. The results are expected to be fully used for various application using stereo images.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.3
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• pp.41-48
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• 2012

Using multi-sensor or multi-temporal high resolution satellite images together is essential for efficient applications in remote sensing area. The purpose of this paper is to estimate geometric difference of translations between high-resolution optical and SAR images automatically. The geometric and radiometric pre-processing steps were fulfilled to calculate the similarity between optical and SAR images by using Mutual Information method. The coarsest-level pyramid images of each sensor constructed by gaussian pyramid method were generated to estimate the initial translation difference of the x, y directions for calculation efficiency. The precise geometric difference of translations was able to be estimated by applying this method from coarsest-level pyramid image to original image in order. Yet even when considered only translation between optical and SAR images, the proposed method showed RMSE lower than 5m in all study sites.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.622-624
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• 2001

영상기반 렌더링(image-based rendering) 기법은 전통적인 컴퓨터 그래픽 기법과는 다르게 장면 생성 시 복잡한 3차원 정보들을 2차원 영상들의 조합으로 표현하여 렌더링 하는 방법이다. 그 중에서 원통맵을 이용한 렌더링은 파노라마 영상을 이요해 관찰자에게 보다 빠르게 실시간으로 장면을 렌더링하여 보여준다. 이러한 영상기반 렌더링에서도 ㅅㄹ제감을 보다 더 높이기 위해서는 빛과 빛에 의해 생기는 그림자, 하이라이트의 역할이 매우 중요하다. 하지만 파노라마 영상의 경우 미리 촬영된 영상들을 사용하므로 실시간으로 동적인 광원의 변화와 그로인한 그림자와 하이라이트 부분을 표현하기 위해서는 변화된 영상들을 재촬영하여 새로운 파노라마 영상을 제작해야 한다. 본 논문에서는 OpenGL을 이용하여 실내 공간을 표현한 원통 영상 기반 환경 맵에서 광원의 위치변화에 의해 가상 하이라이트 (virtual highlight)의 움직임을 파노라마 이미지의 재 촬영 없이 몇 가지 기하학 정보만으로 계산하여 표현해 주는 방법을 제안한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.04a
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• pp.881-883
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• 2015

실제적인 표정인식 응용에서는 테스트 시 등장하는 인물이 트레이닝 데이터에 존재하지 않는 경우가 빈번하여 성능 저하가 발생한다. 본 논문에서는 인물에 독립적인(subject-independent) 표정인식을 위한 얼굴특징을 제안한다. 제안방법은 인물에 공통적인 얼굴 근육 움직임(Action Unit(AU))에 기반한 기하학 정보를 표정 특징으로 사용한다. 따라서 인물의 고유 아이덴티티(identity)의 영향은 감소되고 표정과 관련된 정보는 강조된다. 인물에 독립적인 표정인식 실험결과, 86%의 높은 표정인식률과 테스트 비디오 시퀀스 당 3.5ms(Matlab 기준)의 매우 빠른 분류속도를 달성하였다.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.41-46
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• 2004

최근, 피뢰설비에 대한 수요는 정보통신 등 IT산업의 발전으로 인해 기하급수적으로 성장하고 있다. 21C로 접어들면서 세계는 정보통신기술의 발달을 통해 세계를 하나의 지구촌으로 만들었으며, 모든 물품과 서비스의 표준화로 세계 모든 사람들이 쓰는 물품과 행동양식을 하나의 표준(글로벌 스탠더드)으로 통일화해 나가고 있다. (중략)

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.3
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• pp.183-190
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• 2007

To make use of surveying data obtained from different sensors and different techniques, it is a pre-requite step that register them in a common coordinate system. For this purpose, we developed methodologies to register IKONOS-2 Satellite Imagery using LiDAR(Light Detection And Ranging) data. To achieve this, conjugate features from these data should be extracted in advance. In this study, linear features are chosen as conjugate features. Then, to register them, observation equations are established from similarity measurements of the extracted features and the results was evaluated statistically. The results clearly demonstrate that the proposed algorithms are appropriate to register these data.

• Journal of Korean Society of Transportation
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• v.30 no.5
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• pp.61-69
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• 2012

It is important for highway maintenance and safety assessment to get the accurate highway geometric information. However, it is difficult to acquire good highway geometric information due to missing blueprints or deteriorated highway sections. This research, to get highway geometric information rapidly, has developed a highway geometric analysis algorithm that uses data from vehicles with GPS-IMU integrated system. In conclusion, the result shows that 3.38% of error-ratio for the horizontal alignment and 0.083 absolute value difference for vertical grade comparing with highway drawings. Therefore, the result suggest that the developed method can be applied to the road safety inspection or road safety audit.

• The KIPS Transactions:PartA
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• v.16A no.3
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• pp.153-158
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• 2009

Analysis of 3-dimensional (3D) protein structure plays an important role of structural bioinformatics. The protein structure visualization is the one of the structural bioinformatics and the most fundamental problem. As the number of known protein structure increases rapidly and the study of protein-protein interaction is prevalent, the fast visualization of large scale protein structure becomes essential. The fast protein structure visualization system we proposed is sophisticated and well designed visualization system using geometry instancing technique. Because this system is optimized for recent 3D graphics hardware using geometry instancing technique, its rendering speed is faster than other visualization tools.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.10 no.2
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• pp.67-80
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• 2006

In this paper, we propose a new pointing device that is replaced a mouse as the pointing device with. For reducing the existing pointing device's problem which had marker and high-cost, we develop a new pointing device using computer vision like as a similar human vision system. The proposed system first carries out a real-time movement tracking system using image data which are segmented by color modeling, and finally does the pointing action by 3-D coordinate calculated from stereo geometry information resulting from stereo matching of the segmented region.