• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.2
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• pp.151-157
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• 1996

This study, experimentally, aims at presenting the methodology to construct an efficient digital terrain by com-paring and analyzing the accuracy among the existing Digital Terrain Models, develope 3-D fractal terrain model-ling program by applying digital algorithm of fractal geometry and using turbo pascal, and lastly perform basic research on constructing GSIS-based 3-D fractal terrain modelling system by integrating a PC-based GSIS Pack-age and the 3-D fractal terrain modelling program developed by this paper. The results are as follows -First, the method to produce TIN(Triangulated Irregular Network) by the combination of point data and line data was showed as an alternative to construct efficient Digital Terrain Model. Second, developing GSIS-based 3-D fractal terrain modelling system, applying fractal geometry is the basic research in developing the new terrain modelling method. also, this study presented the possibility of 3-D terrain modelling with the use of fractal.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04a
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• pp.691-693
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• 2002

일반화 다각형(generalized polygons)이란 선분과 호로 둘러싸인 $R^2$영역으로 정의되는 확장된 다각형 개념으로 로보틱스 등의 응용 분야에서 다루는 중요한 도형군이다. 로보틱스에 응용되는 컴퓨터 기하학 알고리즘의 대부분은 선분이나 다각형을 다루도록 개발되어 있어 로봇 작업환경의 다양한 물체들을 선분만으로 모델링해야만 알고리즘의 적용이 가능하다. 기존의 알고리즘들을 일반화 다각형을 다룰 수 있도록 확대한다면 보다 유연한 모델링을 가능하게 할 것이다. 주 논문에서는 컴퓨터 기하학분야의 대표적인 알고리즘인 plane-sweep 알고리즘을 일반화 다각형을 다룰 수 있도록 수정하고 구현한다. 이를 로보틱스이 응용분야중 하나인 고정쇠 문제(fixturing)에 적용한다.

• Electronics and Telecommunications Trends
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• v.16 no.6 s.72
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• pp.56-64
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• 2001

컴퓨터 그래픽스에서 연구되고 있는 영상 기반 모델링과 렌더링 기술은 사진과 같은 사실적인 3차원 모델을 생성하는 새로운 방법을 제시한다. 본 고는 이러한 기술의 토대를 이루고 있는 사진 기하학을 소개하고 이를 이용한 다양한 연구결과와 상용 제품의 응용 기술 동향을 살펴 앞으로의 발전 방향을 짚어 보고자 한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.8
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• pp.27-35
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• 2003

Geometric modeling tool and analysis tool of shell surface have been developed in the different environments and purposes. Thus they cannot be naturally fitted to each other for the integrated design and analysis. In the present study, an integrated framework of geometric modeling, analysis， and design optimization is proposed. It is based on the common representation of B-spline surface patch. In the analysis module, a geometrically-exact shell finite element is implemented. In shape optimization module, control points of the surface are selected as design variables. For the computation of shape sensitivities, semi-analytical method is used. Sequential linear programming(SLP) is adopted for the shape optimization of surfaces. The developed integrated framework should serve as a powerful tool for the geometric modeling, analysis, and shape design of surfaces.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.6
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• pp.605-612
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• 2010

Numberous satellites have monitored the Earth in order to detect changes in a large area. These satellites provide orbit information such as ephemeris data, RPC coefficients and etc. besides image data. If we can use such orbit data afforded by satellite, we can reduce the number of control point for geo-referencing. This paper shows the efficient geometric correction method of strip-satellite RADARSAT-l SAR images acquired by same orbit using ephemeris data, single control point and virtual control points. For accuracy analysis of proposed method, this paper compared the image geometrically corrected by the proposed method to the image corrected by ERDAS Imagine.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.138-141
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• 2003

최근 어패럴 캐드 시스템을 지원하기 위해 3차원 레이저 스캐너로부터 획득된 데이터를 해석적 곡면으로 재구성하는 연구가 활발히 진행되고 있다. 이를 위해 역공학(reverse engineering)을 이용하여 인체를 모델링 하는 시도는 패션, 의료 둥의 분야에서 그 수요가 증가하고 있지만, 그 대상이 되는 인체가 매우 불규칙하기 때문에 기하학, 해석학적으로 접근하기가 어렵고, 시도 또한 미비한 실정이다. (중략)

• The Transactions of the Korea Information Processing Society
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• v.4 no.8
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• pp.2163-2172
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• 1997

SSI(Surface/Surface Intersection)is a fundamental geometric operation which is used in solid and geometric modeling to support trimmed surface and Boolean operations. In this paper, we suggest a new algorithm for tracing along the intersection curve of two regular surfaces. Thus, in this paper, we present a simplicity of computing and second degree continunity. Given a point of intersection curve, it is traced to entire curve of a intersection curve as the initial point of its and the initial point of each of a intersection curve is detected to DFS(Depth First Search) method in the Quadtree and is naturally presented a continuous form.

• Proceedings of the KGS Conference
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• 2004.05a
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• pp.101-101
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• 2004

일반화는 지도요소들을 선택, 과장, 강조, 상징화 등을 통해 공간현상의 의미가 지도에 잘 반영될 수 있도록 지도화 하는 방법이다. 일반화는 지도학에서 오랜 전통을 갖고 있지만, 연구방향은 주로 알고리즘과 공간 데이타 모델링을 중심으로 진행되었다. 일반화는 다양한 과정을 통해 모자이크된 지리적인 현상을 질서 있게 지도화해야 하기 때문에 단순한 기하학적 원리가 아닌 지도학 및 지리학적인 원리를 적용할 필요가 있다. (중략)

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.4
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• pp.64-72
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• 1998

This paper a new approach to the design of machine vision technique with a camera modeling that accounts for major sources of geometric distortion, namely, radial, decentering, and thin prism distortion. Radial distortion causes an inward or outward displacement of a given image point from its ideal location. Actual optical systems are subject to various degrees of decentering , that is , the optical centers of lens design and manufacturing as well as camera assembly. It is our propose to develop the vision system for the pattern recognition and the automatic test of parts and to apply the line of manufacturing. The performance of proposed vision system is illustrated by simulation and experiment.

• Korean Journal of Remote Sensing
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• v.19 no.4
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• pp.285-290
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• 2003

In this paper, a camera modeling method that utilizes ephemeris data and imaging geometry is presented. The proposed method constructs a mathematical model only with parameters that are contained in auxiliary files and does not require any ground control points for model construction. Control points are only needed to eliminate geolocation error of the model that is originated from errors embedded in the parameters that are used in model construction. By using a few (one or two) control points, RMS error of around pixel size can be obtained and control points are not necessarily uniformly distributed in line direction of the scene. This advantage is crucial in large-scale projects and will enable to reduce project cost dramatically.