• Journal of the Korea Computer Graphics Society
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• v.20 no.2
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• pp.1-11
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• 2014

The quality of 2D-to-3D conversion depends on the accuracy of the assigned depth to scene objects. Manual depth painting for given objects is labor intensive as each frame is painted. Specifically, a human is one of the most challenging objects for a high-quality conversion, as a human body is an articulated figure and has many degrees of freedom (DOF). In addition, various styles of clothes, accessories, and hair create a very complex silhouette around the 2D human object. We propose an efficient method to estimate visually pleasing depths of a human at every frame in a monocular video. First, a 3D template model is matched to a person in a monocular video with a small number of specified user correspondences. Our pose estimation with sequential joint angular constraints reproduces a various range of human motions (i.e., spine bending) by allowing the utilization of a fully skinned 3D model with a large number of joints and DOFs. The initial depth of the 2D object in the video is assigned from the matched results, and then propagated toward areas where the depth is missing to produce a complete depth map. For the effective handling of the complex silhouettes and appearances, we introduce a partial depth propagation method based on color segmentation to ensure the detail of the results. We compared the result and depth maps painted by experienced artists. The comparison shows that our method produces viable depth maps of humans in monocular videos efficiently.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.1
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• pp.123-128
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• 2017

This paper deals with performing missions through autonomous navigation using camera and other sensors. Extracting pose of the car is necessary to navigate safely within the given road. Homography is used to find it. Color image is converted into grey image and thresholding and edge is used to find control points. Two control ponits are converted into world coordinates using homography to find the angle and position of the car. Color is used to find traffic signal. It was confirmed that the given tasks performed well through experiments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.2
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• pp.119-128
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• 2002

This study investigates dorsal aspect target strength with fish size, tilt angle and frequency characteristics for the schlegel's black rockfish(Sebastes achlegeli) and the red seabream (Pagrus major). This study was carried out on free swimming fish in a cage in order to obtain acoustic data of the biomass estimation using the scientific echo sounder. The results obtained from this study are summarized as follows; 1 The coefficients of the schlegel's black rockfish and the red seabream using maximum TS with fish length were expressed -63.7dB and -62.6dB at a frequency of 38kHz, -64.4dB and -65.4dB at 120kHz, and -62.4dB and -65.0dB at 200kHz, respectively. 2. The coefficients of the schlegel\`s black rockfish and the red seabream using averaged TS with fish length were expressed -68.4dB and -67.9dB at a frequency of 38kHz, -73.4dB and -72.7dB at 120kHz, and -70.BdE and -73.4dB at 2001Hs, respectively. 3. The coefficients of the schlegel's black rockfish and the red seabream using maximum TS with body weight were expressed -52.0dB and -50.9dB at a frequency of 38kHz, -52.7dB and -53.7dB at 120kHz, and -50.7dB and -53.3dB at 200kHz, respectively. 4. The coefficients of the schlegel's black rockfish and the red seabream using averaged TS with body weight were expressed -56.7dB and -56.2dB at a frequency of 38kHz, -61.7dB and -61.0dB at 120kHz, and -59.ldE and -61.6dB at 200kHz, respectively. 5. Varying the tiIt angle of the two red seabream from -26$^{\circ}$to +25$^{\circ}$, the variation width of target strength expressed smaller at a frequency of 38kHz than at 120kHz and expressed about 3~6dB higher head up than head down at 120kHz.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.6C
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• pp.834-841
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• 2004

There can be lips transformed geometrically in the lip images according to the location or the pose of camera and speaker. This transformation of the lip images changes geometric information of original lip phases. Therefore, for enhancing global lip information by using partial information of lips to correct lip phases transformed geometrically, in this paper we propose a method that can geometrically correct lips. The method is composed of two steps - the feature-deciding step and the correcting step. In the former, it is for us to extract key points and features of source image according to the its lip model and to create that of target image according to the its lip model. In the latter, we decide mapping relation after partition a source and target image based on information extracted in the previous step into each 4 regions. and then, after mapping, we unite corrected sub-images to a result image. As experiment image, we use fames that contain pronunciation on short vowels of the Korean language and use lip symmetry for evaluating the proposed algorithm. In experiment result, the correcting rate of the lower lip than the upper lip and that of lips moving largely than little was highly enhanced.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.398-398
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• 2009

본 논문에서는 카메라의 원근감을 이용하여 케이블의 모드형상을 추출하는 과정을 제안한다. 제안 기법을 검증하기 위해 디지털 카메라와 캠코더를 이용하여 서로 다른 위치에서 동일 화면을 동시에 촬영하고, 촬영된 영상을 사진 변환프로그램을 통해서 초당 30프레임으로 영상이미지를 추출해 낸다. 추출된 좌.우 영상이미지의 영상좌표를 이용하여 케이블에 부착된 표적의 3차원 위치를 결정한다. 이때 디지털 카메라와 캠코더간의 위치 및 자세는 제안된 종속적 상호표정 방법을 통하여 결정한다. 결정된 케이블의 시간이력으로부터 고유진동수과 감쇠비는 다중 템플릿 매칭 알고리즘(multi-template matching algorithm)기법으로 추출하고, 모드형상은 TDD(Time Domain Decomposition)기법을 통하여 추출한다.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.511-513
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• 2004

Camera Calibration should certain)y be achieved to take an accurate measurement using image system. Calibration is to prove the relation between an measurement object and camera and to estimate twelve internal and external parameters. In this paper, we suggest that an algorithm should estimate the external parameters from the road image and use a vanishing point's character from parallel straight lines in a space. also, we use Hough Transform to estimate an accurate vanishing point. Hough Transform has one of the advantages which is an application for each road environment. we assume a variety of environments to prove the usability of a suggested algorithm and show simulation results with a computer.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.10
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• pp.141-146
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• 2000

We introduce the algorithms of 3-D position estimation using a laser sensor for automatic die remodeling. First, a vision sensor based on the optical triangulation was used to collect the range data of die surface. Second, line vector equations were constructed by the measured range data, and an analytic algorithm was proposed for recognizing the die location with these vector equations. This algorithm could make the transformation matrix without any specific corresponding points. To ascertain this algorithm, folded SUS plate was measured by the laser vision sensor attached to a 3-axis cartesian manipulator and the transformation matrix was calculated.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.5
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• pp.1640-1648
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• 1991

본 연구에서는 이러한 편사 함수 최소화의 방법을 적용함에 있어 보다 안정된 수렴성과 계산 시간을 단축시키기 위하여 근접 위치 방법(near position method)을 개 발하여 적용하였다. 근접 위치 방법이란 이론적 해석법으로 풀기가 불가능한 기구학 을 갖는 6관절 로봇을 반복적 해석법을 사용한다는 것을 전제로 하여, 초기 위치를 목 표 위치에 가능한 근접하게 잡아서 반복 계산을 수행하는 방법으로써 로봇의 기구학적 자세에 따른 수렴의 불안정성을 방지하고, 계산 시간을 단축하는데 그 목적이 있다.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.109-112
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• 2008

현재 북한 토지피복 특성 중의 하나인 과도한 산지의 농지로의 전용은 홍수 등 자연재해를 일으키는 원인이 되고 있지만 북한에 대한 참조자료의 부족으로 피해규모나 상황에 대한 이해가 부족하다. 본 연구는 북한 양강도 산간지역을 대상으로 개간농지와 산림의 토지피복특성을 가을시기(2005 년 10 월 25 일) Quickbird (<0.6m) 위성영상의 육안분석과 분광특성을 이용하여 정확한 토지피복분류에의 기초 정보를 제공하는 것을 목적으로 한다. 토지피복 유형별 Training area 의 ROI(Region of Interest)의 면적은 2500pixel 로 하였고, 이것을 다시 .shp 파일로 변환하여 GoogleEarth 에서 표고 및 경사 등 보다 자세한 지형지물을 확인하였다. Quickbird 영상의 NDVI 분석을 통해 0.2 정도에서 식생과 농경지로 구분하는 임계값(Threshold)을 추정할 수 있었지만 늦게까지 추수를 끝내지 않은 농작물이나 이모작 농작물의 경우는 산림과 혼재되어 나타나고 있었다. 또한, 산림의 북사면은 수역 다음으로 낮은 NDVI 값을 나타내어 지형의 영향이 나타나고 있음을 알 수 있었다.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.85-89
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• 2006

Propulsion System provides the required velocity change impulse for orbit transfer from parking orbit to mission orbit and three-axis vehicle attitude control impulse. New LEO Satellite propulsion system (PS) will be an all-welded, monopropellant hydrazine system. The PS consists of the subassemblies and components such as Thrusters, Propellant Tank, Pressure Transducer, Propellant Filter, Latching Isolation Valves, Fill/Drain Valves, interconnecting propellant line assembly, and thermal hardwares for operation-environment control of the PS. In this study, preliminary design process of LEO Satellite propulsion system will be summarized.