• 한국생산제조학회지
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• 제20권4호
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• pp.386-394
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• 2011

This paper is concerned with the application of the vision control scheme for robot's point placement task in discontinuous trajectory caused by obstacle. The proposed vision control scheme consists of four models, which are the robot's kinematic model, vision system model, 6-parameters estimation model, and robot's joint angles estimation model. For this study, the discontinuous trajectory by obstacle is divided into two obstacle regions. Each obstacle region consists of 3 cases, according to the variation of number of cameras that can not acquire the vision data. Then, the effects of number of cameras on the proposed robot's vision control scheme are investigated in each obstacle region. Finally, the practicality of the proposed robot's vision control scheme is demonstrated experimentally by performing the robot's point placement task in discontinuous trajectory by obstacle.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.431-433
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• 2006

The goal of this paper is improvement of vision inspection accuracy by using histogram specification operation. The histogram is composed of horizontal axis of image intensity value and vertical axis of pixel number in image. In appearance vision inspection, the histogram of reference image and input image are different because of minutely lighting distinction. The minutely lighting distinction is main reason of vision inspection error in many cases. Therefore we made an effort for elevation of vision inspection accuracy by making the identical histogram of reference image and input image. As a result of this area separation histogram specification algorithm, we could increase the exactness of vision inspection and prevent system error from physical and spirit condition of human. Also this system has been developed only using PC, CCD Camera and Visual C++ for universal workplace.

• 전자통신동향분석
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• 제36권2호
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• pp.56-64
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• 2021

Many computer vision algorithms are computationally expensive and require a lot of computing resources. Recently, owing to machine learning technology and high-performance embedded systems, vision processing applications, such as object detection, face recognition, and visual inspection, are widely used. However, on-devices need to use their resources to handle powerful vision works with low power consumption in heterogeneous environments. Consequently, global manufacturers are trying to lock many developers into their ecosystem, providing integrated low-power chips and dedicated vision libraries. Khronos Group-an international standard organization-has released the OpenVX standard for high-performance/low-power vision processing in heterogeneous on-device systems. This paper describes vision libraries for the embedded systems and presents the OpenVX standard along with related trends for on-device vision system.

• 인지과학
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• 제21권2호
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• pp.339-357
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• 2010

본 연구에서는 두 가지 읽기 방법으로 저시력인과 정상시력인의 문장 맥락효과를 비교하였다. 실험 1에서는 자기조절읽기(self-paced reading) 방법을, 실험 2에서는 신속순차제시(rapid serial visual presentation) 방법을 사용하여 문장과 무선단어열에서 정상시력 참가자와 저시력 참가자의 읽기속도를 비교하였다. 두 실험 결과에서 저시력 참가자의 읽기속도는 정상시력 참가자에 비해 현저히 감소하였으나, 맥락효과는 읽기 방법에 따라 상반된 양상을 보였다. 자기조절읽기를 사용한 실험 1에서는 정상시력보다 저시력에서 맥락효과가 컸고, 신속순차제시를 사용한 실험 2에서는 저시력보다 정상시력에서 맥락효과가 컸다. 본 결과는 맥락 정보가 처리될 시간이 충분히 허용되는 읽기 상황에서는 정상시력에 비해 저시력 읽기에서 맥락의 역할이 증가하나, 시간적 제약이 주어지는 읽기 상황에서는 반대로 정상시력에 비해 저시력 읽기에서 맥락의 역할이 감소함을 시사한다.

• 한국안광학회지
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• 제15권2호
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• pp.185-193
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• 2010

목적: 이 연구의 목적은 시기능 훈련 대상자들의 시기능 훈련방법의 차이에 따른 시기능 증상 개선 효과를 조사하였다. 방법: 시기능 훈련 대상자는 안질환과 조절이상 및 수직사위가 없는 양안시 이상자 35명을 대상으로 추적 관찰하였고, 훈련기간은 8주간 매주 한번은 안경원에 방문하여 시기능 훈련에 따른 변화를 측정하였다. 결과: 시기능 훈련 대상자의 시기능 훈련방법의 차이에 따른 기능적 및 감각적 증상이 개선되었다. 그리고 Worth 4 Dot검사, 입체시 검사 및 적색렌즈 융합 속도 검사는 유사한 결과를 보여 주었다. 결론: 본 연구에서 시기능 훈련 방법에 따라 환자의 사위량, 기능적 및 감각적 증상 변화가 있는 것으로 나타났다.

• Journal of Biosystems Engineering
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• 제22권2호
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• pp.210-216
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• 1997

A study to select ground colors of Fuji apple for maturity index which are needed to standardize grading of the apples is presented. Two extreme colors of immature and fully mature Fuji and Zonagold apples produced in Korea were determined. Various ground colors of Fuji apple between the two extreme colors were collected and classified by human vision and colors of Fuji apple for maturity index were selected from the classification. Coordinates of the selected colors in xy chromaticity diagram were determined by spectrophotometers to define them in a standard coordinate system. Coordinates of the colors in r-g chromaticity diagram using a color machine vision system were also determined to use the colors in apple grading by the machine vision system. Grading Fuji apples using the machine vision system was performed and result of the grading was compared with Ending results of human vision and colorimeter. The comparison was performed with the same Fuji apple samples and showed 65% md 75% of same grades, respectively, as the grades determined by the machine vision system. Differences of fading performance between the compared three grading methods were explained as mainly because of the differences of observation area of the grading methods.

• 문화기술의 융합
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• 제8권1호
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• pp.409-415
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• 2022

컴퓨터 비전은 카메라를 이용하여 측정대상의 영상을 획득하고, 추출하고자 하는 특징 값, 벡터, 영역 등을 알고리즘과 라이브러리 함수를 응용하여 검출한다. 검출된 데이터는 사용하는 목적에 따라 다양한 형태로 계산되고 분석한다. 컴퓨터 비전은 다양한 곳에 활용되고 있으며, 특히 자동차의 부품을 자동으로 인식하거나 품질을 측정하는 분야에 많이 활용된다. 컴퓨터 비전을 산업분야에서 머신비전이라는 용어로 활용되고 있으며, 인공지능과 연결되어 제품의 품질을 판정하거나 결과를 예측하기도 한다. 본 연구에서는 자동차 부품의 품질을 판정하기 위한 비전시스템을 구축하고, 생산된 데이터에 5개의 머신러닝 분류 모델을 적용하여 그 결과를 비교하였다.

• International Journal of Aeronautical and Space Sciences
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• 제17권3호
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• pp.366-377
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• 2016

This paper presents a vision-based guidance method that allows a fixed-wing aircraft to orbit around a target at a given radius. The guidance method uses a simple formula that regulates a relative side-bearing angle estimated by a vision system. The global asymptotic stability of the associated guidance law is demonstrated, and a linear analysis is performed to facilitate the proper selection of the relevant control parameters. A flight experiment is presented to demonstrate the feasibility and performance of the proposed guidance method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.836-841
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• 2004

This paper describes ASIC design for brightness revision control, A LED Pixel Matrix (LPM) design and LPM in natural color LED vision. A designed chip has 256 levels of gradation correspond to each Red, Green, Blue LED pixel respectively, which have received 8bit image data. In order to maintain color uniformity by reducing the original rank error of LED, we adjusted the specific character value 'a' and brightness revision value 'b' to pixel unit, module unit and LED vision respectively by brightness characteristic function with 'Y=aX+b'. In this paper, if designed custom chip and brightness revision control method are applied to manufacturing of natural color LED vision, we can obtain good quality of image. Furthermore, it may decrease the cost for manufacturing LED vision or installing the plants.

• 전기학회논문지
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• 제60권1호
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• pp.161-166
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• 2011

This paper addresses the vision based autonomous walking control system. To handle the obstacles which exist beyond the field of view(FOV), we used the 3d panoramic depth image. Moreover, to decide the avoidance direction and walking motion of a humanoid robot for the obstacle avoidance by itself, we proposed the vision based path planning using 3d panoramic depth image. In the vision based path planning, the path and walking motion are decided under environment condition such as the size of obstacle and available avoidance space. The vision based path planning is applied to a humanoid robot, URIA. The results from these evaluations show that the proposed method can be effectively applied to decide the avoidance direction and the walking motion of a practical humanoid robot.