• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.07a
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• pp.276-278
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• 2020

포인트 클라우드 콘텐츠는 실제 사물을 수천만 개의 점으로 표현하는 미디어 콘텐츠이다. 각 점들은 색상 값과 3 차원 공간상의 위치로 구성 되어있다. 이러한 컨텐츠를 영상 미디어로 활용하기 위해서는 실시간으로 네트워크를 통해 전달되는 포인트 클라우드 콘텐츠를 고품질의 영상으로 시각화 할 필요성이 있다. 본 연구에서는 포인트 클라우드 콘텐츠를 구성하는 점들이 임의의 순서로 입력될 때, 각 점이 투영된 형상을 원형으로 나타내어 블렌딩하는 원형 splat 기반의 실시간 시각화 기법을 제안한다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.5
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• pp.13-24
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• 2011

This paper deals with a 3D-pose (orientation and position) estimation problem of a circular object in 3D-space. Circular features can be found with many objects in real world, and provide crucial cues in vision-based object recognition and location. In general, as a circular feature in 3D space is perspectively projected when imaged by a camera, it is difficult to recover fully three-dimensional orientation and position parameters from the projected curve information. This paper therefore proposes a 3D pose estimation method of a circular feature using a coplanar point. We first interpret a circular feature with a coplanar point in both the projective space and 3D space. A procedure for estimating 3D orientation/position parameters is then described. The proposed method is verified by a numerical example, and evaluated by a series of experiments for analyzing accuracy and sensitivity.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.7
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• pp.619-628
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• 2000

Abstract Perspective views provide a powerful depth cue and thus aid the interpretation of complicated images. The main drawback of current perspective volume rendering is the long execution time. In this paper, we present an efficient perspective volume rendering algorithm based on coherency between rays. Two sets of templates are built for the rays cast from horizontal and vertical scanlines in the intermediate image which is parallel to one of volume faces. Each sample along a ray is calculated by interpolating neighboring voxels with the pre-computed weights in the templates. We also solve the problem of uneven sampling rate due to perspective ray divergence by building more templates for the regions far away from a viewpoint. Since our algorithm operates in object-order, it can avoid redundant access to each voxel and exploit spatial data coherency by using run-length encoded volume. Experimental results show that the use of templates and the object-order processing with run-length encoded volume provide speedups, compared to the other approaches. Additionally, the image quality of our algorithm improves by solving uneven sampling rate due to perspective ray di vergence.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2005.11a
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• pp.229-232
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• 2005

컴퓨터 비전을 기반으로 하는 인간과 컴퓨터의 상호작용(Human computer Interaction, HCI)에 대한 연구는 영상처리 분야에서 큰 축을 담당하고 있으며, 특히 얼굴인식 연구는 HCI 분야에서 가장 중요한 영역들 중의 분야이다. 이러한 얼굴인식 기반의 HCI 시스템을 구현하기 위해서는 영상 내에 존재하는 얼굴을 정확히 검증하는 것이 선행되어야 한다. 본 논문에서는 피부색상과 원형 투영 과정에 의한 특징 추출을 이용한 특징점 기반의 얼굴 검출 기법을 제안한다. 본 논문에서 제안하는 얼굴검출 기법은 얼굴의 크기 및 평면적 회전(rotation)에 대하여 강인한 얼굴검출 성능을 보여준다.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.3
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• pp.33-33
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• 2001

본 논문에서는 단일 글꼴에 의존하는 원형 패턴 벡터(circular pattern vectors)를 이용하여 위치 이동, 크기 변화 그리고 회전에 무관한 새로운 인쇄체 한글 인식 알고리즘을 제안한다. 제안한 알고리즘은 2진 형태론(binary morphology)을 이용하여 입력 문자에 존재하는 잡음(noise)을 제거한 후, 원형 패턴벡터를 추출한다. 추출된 원형 패턴 벡터는 주어진 문자의 무게 중심을 원의 중심으로 하여 그린 여러 원주 상에 위치한 공간적인 분포 값을 나타내는 것이다. 마지막으로, 실험 문자는 기준 원형 패턴 벡터와 실험 원형 패턴 벡터간의 거리가 최소가 되는 기준 문자로 인식하게 된다. 제안한 알고리즘의 성능을 평가하기 위해, 크기 변화와 회전 변형이 있는 완성형 바탕체 한글 2,350자를 대상으로 모의 실험을 수행하였다. 제안한 알고리즘은 기존의 고리 투영 알고리즘보다 크기 변화와 회전 변형이 있는 한글 인식에 있어서 우수함을 보였다.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.97-104
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• 2009

This paper describes comparison and analysis of methodology which enables us in order to search the projection technique of optimum for projection in the plane. For this methodology, we applies the high-dimensional facial motion capture data respectively in linear and nonlinear projection techniques. The one core element of the methodology is to applies the high-dimensional facial expression data of frame unit in PCA where is a linear projection technique and Isomap, MDS, CCA, Sammon's Mapping and LLE where are a nonlinear projection techniques. And another is to find out the methodology which distributes in this low-dimensional space, and analyze the result last. For this goal, we calculate the distance between the high-dimensional facial expression frame data of existing. And we distribute it in two-dimensional plane space to maintain the distance relationship between the high-dimensional facial expression frame data of existing like that from the condition which applies linear and nonlinear projection techniques. When comparing the facial expression data which distribute in two-dimensional space and the data of existing, we find out the projection technique to maintain the relationship of distance between the frame data like that in condition of optimum. Finally, this paper compare linear and nonlinear projection techniques to projection high-dimensional facial expression data in low-dimensional space and analyze it. And we find out the projection technique of optimum from it.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.451-460
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• 2013

Project to deal with cultural archetype as a material for creation to develop modern one has continued. But it would be meaningless if cultural archetype is simply reproduced into modern one with modern medium so that such contents cannot see through desire that the general public, that is, contemporary recipients want. This is because desire of people who lived in the past is not completely same as one of modern people. This study began to make convergence from Bulgasalee(不可殺伊) as a Korean cultural archetype to cultural contents fit to modern times. To develop creative character based on ground for existing Bulgasalee(不可殺伊), these were investigated - method and meaning of modern transformation for classics, economic value of the character, and examples to understand direction of future development. Bulgasalee(不可殺伊) as a Korean cultural archetype is Korean style monster where wish of contemporary people was reflected so that it has character of anti-war and hero. To eat iron and be related to fire is a unique character that only Bulgasalee(不可殺伊) has. Bulgasalee(不可殺伊) re-born in modern sense based on such characters is equipped with tool to treat iron as arms and to it, image of fireman is reflected. It is thought that this study not only suggested character for successful modern transformation of cultural archetype but also newly developed value that the character has.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.4
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• pp.512-519
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• 2012

This paper proposes a 3-D pose (positions and orientations) estimation system based on the recognition of circular ring patterns. To deal with monocular vision-based pose estimation problem, we specially design a circular ring pattern that has a simplicity merit in view of object recognition. A pose estimation procedure is described in detail, which utilizes the geometric transformation of a circular ring pattern in 2-D perspective projection space. The proposed method is evaluated through the analysis of accuracy and precision with respect to 3-D pose estimation of a quadrotor-type vehicle in 3-D space.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.159-162
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• 2005

지형/지물 이미지, 특히 항공.위성사진의 경우 대부분 비슷한 색상과 질감을 갖는다. 따라서 지형/지물 이미지 데이터베이스에서 질의 이미지를 효율적으로 검색하기 위해 이미지의 형태 특징을 이용해야 한다. 본 논문은 지형/지물의 형태 특성을 고려한 형태 특징 추출 방법을 제안한다. 이 방법은 기존의 직각 좌표계를 이용한 투영 방법을 발전시킨 것으로 원형 좌표계를 이용하여 일정 간격의 방향에서 투영 연산을 수행한다. 이를 통해 본문에서 언급하는 세 가지 특징을 추출한다. 이 방법은 이미지의 방향/크기/위치에 관계없이 이미지의 형태 특징을 추출 할 수 있다. 기존의 형태 특징 추출 방법인 CSS 방법과 비교.실험을 통해 본 논문에서 제안한 방법의 성능과 장점을 보인다.

• Journal of the Korea Concrete Institute
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• v.14 no.6
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• pp.982-988
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• 2002

Current design equations for shear strength of reinforced concrete columns generally overestimate the shear strength contribution by the circular transverse reinforcement. This is due to the simplification of the discrete distribution of the reinforcement to the continuous one and the imprudent application of the classical truss model to the circular section, which is different in shear-resisting mechanism from the rectangular section. This study presents a rational model for the prediction of shear strength contribution by the circular transverse reinforcement considering the starting location of a diagonal crack, the number of transverse reinforcing bars crossing the main crack and the geometrical strength component of the transverse resistance. It was found that, for lower amount transverse reinforcement, the crack starting point and the number of crack crossing bars greatly influence the shear-resisting capacity. Proposed model leads to a reliable design equation which is derived using a linear regression method and is in good agreement with the lower bound of exact strength curve.