• Proceedings of the Korea Information Processing Society Conference
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• 2012.11a
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• pp.359-361
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• 2012

본 논문에서는 깊이영상에서 상반신 포즈 분석을 위하여 원통좌표시스템을 제안한다. 깊이영상에서 포즈 후보 영역을 설정하고, 포즈 후보 영역을 이용하여 카메라로부터 신체 중심점까지의 거리와 신체 특징에 따라 원통좌표계를 설정한다. 그리고 밝기값으로 표현되는 깊이 정보를 이용하여 특징벡터를 추출한다. 추출된 원통좌표계의 특징벡터는 원형의 특징공간에 표현되고 포즈 패턴으로 분류된다. 그리고 포즈 패턴들은 특징벡터들의 평균값을 이용하여 학습되고 미리 정의된 포즈 패턴들과 유클리디언 거리로 비교하여 포즈로 분류된다. 본 논문은 상반신 포즈 후보 영역에 동적인 원통 모델을 적용하여 간단한 연산을 통해 머리와 몸통, 팔을 구분할 수 있도록 효과적인 포즈 정보 추출에 목적을 두고 있다.

• Journal of the Korea Computer Graphics Society
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• v.3 no.2
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• pp.55-63
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• 1997

This paper presents a method of detecting motion isometry from the motions of two objects in a three-dimensional space. We define the motion isometry based on the group theory and a newly defined coordinate system. Motion isometry can be detected using the coordinate system which we call Motion Specific Coordinate System(MSCS). In addition, we present an algorithm if two motions are isometric using the coordinate system. The algorithm can detect the difference in the motions of objects irrespective of their positions or the directions of their motions in a space. The algorithm can also detect the motion difference in the case of segmented objects which have several joints. The motion quantity is represented by translation values or rotation angles about some axes.

• Journal of Digital Convergence
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• v.19 no.2
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• pp.195-202
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• 2021

In this study, from a long-term perspective, we tried to find and present a plan to apply the results of transformation of cadastral coordinates to the world geodetic system in stages for cadastral records of graphical and digital cadastral area. There was a case where the difference in area before and after the transformation occurred irregularly in the transformation result of the cadastral coordinate system currently being promoted. In addition, it was found that transformation errors in cadastral non-coincidence areas occurred accumulatively, and the period for acquiring world geodetic results for cadastral reference points was insufficient. In order to solve this problem, the study proposed a plan to provide spatial information and related fields through advancement of continuous cadastral maps, etc. for maps that have been primarily transformed by the end of 2020. In addition, the maps used for cadastral surveying purposes were presented in the direction of applying them to cadastral records in numerical form in the long term to conform to the characteristics of graphical and digital cadastral area. It is expected that more stable cadastral record will be reflected by applying the world coordinate transformation performance by dividing the graphical and digital cadastral area.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.469-475
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• 2015

This paper describes about the method for designing an extended Kalman filter to accurately measure the position of the spatial-phase system using a semiconductor sensor. Spatial position is expressed by the correlation of the rotated coordinate system attached to the body from the inertia coordinate system (a fixed coordinate system). To express the attitude, quaternion was adapted as a state variable, Then, the state changes were estimated from the input value which was measured in the gyro sensor. The observed data is the value obtained from the acceleration sensor. By matching between the measured value in the acceleration sensor and the predicted calculation value, the best variable was obtained. To increase the accuracy of estimation, designation of the extended Kalman filter was performed, which showed excellent ability to adjust the estimation period relative to the sensor property. As a result, when a three-axis gyro sensor and a three-axis acceleration sensor were adapted in the estimator, the RMS(Root Mean Square) estimation error in simulation was retained less than 1.7[$^{\circ}$], and the estimator displayed good property on the prediction of the state in 100 ms measurement period.

• Spatial Information Research
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• v.11 no.4
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• pp.481-491
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• 2003

This study aims at generating a continuous map by coordinates transformation between cadastral maps with different surveying origins. The continuous cadastral map is useful in various fields of GIS. For this purpose, an experimental study was conducted at Osan-Si, Kyonggi Province in cooperation with related institutions. In this study, three control point zone, large, medium, and small zone were to!;ted. For each control point, the currently used data were compared with the data at the surveyed time. About coordinate transformation method, we tested Helmert, Affine, and Polynomial methods which are the most representative among 2-dimensional coordinate transformations. These three transformation methods were evaluated according to variation of transformed parcel shape and agreement with neighboring areas. As the result of the evaluation, Affine transformation in large zone is the most appropriate coordinate transformation method fer Osan-Si.

• Journal of Korean Society for Geospatial Information Science
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• v.1 no.2 s.2
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• pp.153-158
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• 1993

It is important to establish the transformational relation between scanned image coordinates and digital image coordinates because the coordinate system of digital image is transformed from scanned image coordinate system through scanning work. And, some researches are required in scanning works to correct the deformation that is due to the motion of scanner. In this study, some procedures are applied to determine the optimal calibration model equation which can calibrate the scanner. As a result the optimal calibration model equation for the object scanner is determined The procedure of this study can applied to the calibration of other types of scanner, because the procedures are done with the analysis of geometrical properties rather than the analysis of physical properties.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1799-1803
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• 2008

표면영상유속계는 하천 표면의 영상을 분석하여 유속을 산정하는 매우 실용적이며 간편한 장비이다. 그러나, 표면영상유속계를 이용하여 유량을 산정하고자 할 경우, 하천 표면의 평면 측량 자료와 하천의 단면 측량 자료가 반드시 필요하다. 이 때문에 표면영상유속계의 간편성과 유용성에도 불구하고, 이용자들이 쉽게 이용하기 어렵다는 그릇된 인식을 줄 수 있다. 만일 효율적이고 간편하게 하천의 단면을 추정할 수 있다면, 표면영상유속계를 마치 일반적인 프로펠러 유속계처럼 쉽게 이용할 수 있을 것이다. 이 연구는 일반적인 평면 측량없이, 두 대의 비디오 카메라로 이루어진 표면 영상 유속계를 이용하여 하천 평면을 계측하는 방법을 개발하는 것이다. 이를 통하여 표면 영상 분석 과정을 반자동화할 수 있게 된다. 두 대의 카메라를 이용한 평면 측량은 사진 측량 분야이나 컴퓨터 비전 분야에서 오랫 동안 연구되어 왔다. 이 기법을 표면영상유속계에 적용함으로써 간단하게 하천의 평면 좌표를 구할 수 있도록 하였다. 두 대의 카메라에 대해서는 직접 선형 변환법을 이용하여 내부 표정과 외부 표정을 수행하여 변환의 매개 변수들을 추정하였다. 추정된 변수들과 공간 전방 교회법을 이용하여 하천의 고정된 기준점들의 좌표를 측정한다. 측정된 좌표점들은 기울어진 영상을 연직으로 사영된 평면으로 변환하는 데 이용되며, 이 과정을 통하여 번거로운 하천의 평면 측량 과정을 생략할 수 있게 되었다. 온천천에 실제 적용하여 본 결과, 결과는 아직은 만족할 만한 정도는 아니나, 보다 정밀한 카메라의 보정 등을 통하여 보다 나은 결과를 도출할 수 있을 것으로 기대된다.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1827-1830
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• 2003

본 논문은 인간의 Perception을 기준으로 인간이 구분할 수 있는 다양한 Display들의 Color Gamut 체적들을 정량적으로 평가하는 방법을 제안하였다. 기존의 Color Gamut의 크기를 구하는 방법은 CIE-u'v' 좌표계에서 R, G, B Primaries의 좌표에 해당하는 꼭지점으로 이루어진 삼각형의 넓이를 구함으로써 표현할 수 있는 Color의 개수를 구하였다 그러나 이 방법은 CIE-UCS Chart 자체가 2 Dimension이고, Non-Uniform Color Space이므로 정확하게 구했다고 할 수 없다. 이를 해결하기 위하여 본 논문에서는 Uniform Color Space 인 CIE-L/sup */a/sup */b/sup */ 좌표계에서 3 차원 공간에서 Color의 개수를 구함으로써, 구분할 수 있는 Color Gamut의 체적을 인간의 Perception을 기준으로 평가하는 정량적인 기법에 대해 논하였고, 이를 4종류의 다양한 Display Type들에 적용, 그 결과를 비교하였다.

• Geophysics and Geophysical Exploration
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• v.5 no.3
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• pp.206-216
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• 2002

The finite element method (FEM), a powerful numerical modeling tool for solving various engineering problems, is frequently applied to three-dimensional (3-D) modeling thanks to its capability of discretizing and simulating the shape of model with finite number of elements. Considering the accuracy of the solution and computing time in modeling of engineering problems, it is preferable to construct physical continuity and simplify mesh system. Although there exist systematic mesh generation systems for arbitrary shaped model, it is hard to model a simple cylinder in terms of 3-D coordinate system especially in the vicinity of the central axis. In this study I adopt cylindrical coordinate system for modeling the 3-D model space and define the origin of the coordinates with mathematically clear coordinate transformation. Since we can simulate the whole space with hexahedral elements, the cylindrical coordinate system is effective in handling the 3-D model structure. The 3-D do resistivity modeling scheme developed in this study provides basie principle for borehole-to-surface resistivity survey, which can be a useful tool for the application to environmental problem.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.69-76
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• 2007

High-frequency electromagnetic (EM) wave propagation associated with borehole ground-penetrating radar (GPR) is a complicated phenomenon. To improve the understanding of the governing physical processes, we employ a finite-difference time-domain solution of Maxwell's equations in cylindrical coordinates. This approach allows us to model the full EM wavefield associated with crosshole GPR surveys. Furthermore, the use of cylindrical coordinates is computationally efficient, correctly emulates the three-dimensional geometrical spreading characteristics of the wavefield, and is an effective way to discretise explicitly small-diameter boreholes. Numerical experiments show that the existence of a water-filled borehole can give rise to a strong waveguide effect which affects the transmitted waveform, and that excitation of this waveguide effect depends on the diameter of the borehole and the length of the antenna.