• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.697-704
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• 2000

This study presents methodology and tools for remote measurement of the orientation of the rock parting surfaces. Two close circuit video camera capture the pictures of a rock excavation surface while a laser beam scans the surface. Positions of the laser beams in the two digital images are recognized by image processing. Using the stereoscopic concept, three dimensional coordinations of the rock surface and the orientation of the rock parting planes are calculated. Point, cross and line type laser beams are tested for better image processing results and measurement accuracy of the coordinates. According to a simple accuracy test, cross beam show better results than the point beam. However, line beam show more promising results for the measurement of the rock parting surfaces.

• 대한임베디드공학회논문지
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• 제3권3호
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• pp.151-157
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• 2008

In this paper, we propose a three dimensional distance measurement method for a stereo system by using web cams. Using a parallel stereo system, a robot gets two images from each webcam and equalize brightness of both images. And we suggest an image processing method such as labeling, isolating an object from background and finding center of an object. We also propose a method of calculating the focal distance by using least square algorithm based on triangulation and we can reduce calculation error by this method. From experimental results, we show that the proposed method can be effective for 3D distance measurement.

• Journal of Information Processing Systems
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• 제12권4호
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• pp.591-611
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• 2016

High dimensional space is the biggest problem when classification process is carried out, because it takes longer time for computation, so that the costs involved are also expensive. In this research, the facial space generated from homogeneous and non-homogeneous polynomial was proposed to extract the facial image features. The homogeneous and non-homogeneous polynomial-based eigenspaces are the second opinion of the feature extraction of an appearance method to solve non-linear features. The kernel trick has been used to complete the matrix computation on the homogeneous and non-homogeneous polynomial. The weight and projection of the new feature space of the proposed method have been evaluated by using the three face image databases, i.e., the YALE, the ORL, and the UoB. The experimental results have produced the highest recognition rate 94.44%, 97.5%, and 94% for the YALE, ORL, and UoB, respectively. The results explain that the proposed method has produced the higher recognition than the other methods, such as the Eigenface, Fisherface, Laplacianfaces, and O-Laplacianfaces.

• 한국해양공학회지
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• 제12권1호
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• pp.113-119
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• 1998

An experimental study was carried out in a three-dimensional cubic cavity driven by 2-dimensional plane Poiseuille flow for three kinds of Reynolds number, $10^4$, 3 $\times$ $10^4$ and 5 $\times$ $10^4$ based on the cavity width and cavity inlet mean flow velcoity. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system. Laser based illumination and two-frame grey-level cross correlation algorithm are adopted. Severe unsteady flow fluctuation within the cavity are remarkable at above Re = 3 $\times$ $10^4$ Reynolds numbers and sheared mixing layer phenomena are also found at the region where inlet driving Poiseuille flow is collided with the clock-wise rotating main primary vortex at upper center area. Instant velocity profiles reveal that deformed forced vortex formation is observed throughout the separate two areas.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1971-1975
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• 2003

This paper describes a technique, which analyzes the functional instability of the ankle using three-dimensional scanner. The technique is based on the structured light pattern projection method, which is performed by using one digital still camera and one LCD projector. This system can be easily realized with the low cost. The measuring result has high accuracy. The measuring error is about 0.2 mm or less. Using this technique the three-dimensional posture of the leg and foot of the target person are measured and analyzed.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 춘계학술발표대회 논문집
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• pp.201-204
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• 2001

A Confocal Laser Scanning Microscope (CLSM) is applied to determine three-dimensional fiber orientation states in injection-molded short fiber composites. Since the CLSM optically sections the composites, more than two planes either on or below the surface of composites can be obtained. Therefore, three dimensional fiber orientation states are determined without destruction. To predict the orientation states, velocity and temperature fields are calculated by using a hybrid FEM/FDM method. The change of orientation state during packing stage is also considered by employing a compressible Hele-Shaw model. The predicted orientation states show good agreement with measured ones. However, some differences are found at the end of cavity. They may result from other effects, which are not considered in the numerical analysis.

• 대한인간공학회지
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• 제20권3호
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• pp.77-88
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• 2001

A three dimensional body scanner for anthropomentric measurement has been developed. In this study, the slit laser beam projection method followed by digital image processing was used to provide accurate spatial data with the typical optical triangulation method to overcome the many difficulties in traditional in accurate and time-consuming tactic measurement method using rulers and gauges. Compared with other commercialized scanners. this system can obtain a relatively wide range of data at a much lower cost by the specially designed scanning process such as the simultaneous acquisition of vertical and horizontal body cross-section profiles.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1987년도 춘계학술발표회 논문집
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• pp.56-59
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• 1987

In this study the moving information extraction techniques of moving objects are processed digital imaqe data by sampling three frames in a fixed-bacqround two-dimensional line sequence image the brightness of interframe are compared to extract difference image and difference image are two level formed and neighber averged From neigbber averaged image the parameters for recoqnition of the object are the number of contorur pixels, the number of vertex points and the distance between the vertex points Agtercomparing the same object the moving distance obtained from the coordinate which is constructed by the bit processing of the digital data and the moving velocity is obtained from the moving distance and the time interval between the first andsecond sampled frames.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 추계학술대회
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• pp.147-148
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• 2010

Recently, advancement in the visual technology has lead to the further development of the three dimensional (3D) imaging systems. The visual perception to view a pair of images simultaneously, is a crucial factor to build a stereoscopic 3D image. In this paper, we present the depth cues between the intensities of the two images when viewing with both eyes. Due to this stereoscopic effect, objects at different distances from the eyes differ in their horizontal positions, giving the depth cue of horizontal disparity. By simple image processing technique, we also present the binocular disparity map between the two images. A median filter has been used to filter out all the noises occurring in the disparity map image.

• Investigative Magnetic Resonance Imaging
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• 제13권1호
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• pp.22-30
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• 2009

목적 : 자기공명영상화는 보통 긴 스캔 시간으로 인해 환자의 움직임이 큰 문제가 된다. 이러한 환자의 움직임을 보정하기 위한 한가지 방법인 영상의 엔트로피(entropy)를 이용한 후처리 방법은 다른 추가 데이터 획득 없이 효과적으로 움직임 인공물을 줄일 수 있음을 보였다. 하지만 이 방법의 가장 큰 문제는 처리 시간이 매우 길다는데 있다. 본 연구에서는 움직임 보정 처리시간을 줄이는 방법을 제안한다. 대상 및 방법 : 전체적인 보정 시간을 줄이기 위한 첫 번째 방법은, 퓨리에 변환의 분리성을 이용하여 전체적인 퓨리에 변환시간을 줄일 수 있다. 영상의 엔트로피 기준을 대신해 영상의 전체 화소의 합(pixel sum)을 움직임 보정의 기준으로 이용하여 영상 기준을 계산하는 시간을 절반 이하로 줄일 수 있다. 마지막으로 부분 퓨리에 재구성 방법을 조합하여 움직임의 영향을 보정하는 k-공간의 데이터 량을 줄임으로써 전체적인 처리 시간을 큰 폭으로 줄일 수 있다. 결과 : 제안한 방법을 사용하여 보정한 영상의 품질은 엔트로피를 이용한 보정 방법과 거의 흡사했으며, 대신 전체적인 처리 시간을 2차원 영상에서 15%로, 3차원 영상에서 30%로 줄일 수 있었다. 결론 : 제안한 방법을 병렬 영상화 기법 등과 결합하여 영상 보정 시간을 더욱 줄일 수 있을 것으로 기대한다. 제안하는 방법은 다른 보정 기법을 사용할 수 없을 때, 영상에서 움직임의 영향을 줄이는 방법으로 유용할 것으로 기대한다.