• Title/Summary/Keyword: Vision Test

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Vision System Design for Automatic Test and Repair of Steam Generator Holes in Nuclear Power Plants (원자력발전소 증기 발생기의 자동검사 및 수리를 위한 비젼시스템 설계)

  • 한성현
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.6
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    • pp.5-14
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    • 1998
  • In this paper we propose a new approach to the development of the automatic vision system to examine and repair the steam generator tubes at remote distance. In nuclear power plants, workers are reluctant of works in steam generator because of the high radiation environment and limited working space. It is strongly recommended that the examination and maintenance works be done by an automatic system for the protection of the operator from the radiation exposure. Digital signal processors are used in implementing real time recognition and examination of steam generator tubes in the proposed vision system. Performance of proposed digital vision system is illustrated by simulation and experiment for similar steam generator model.

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Further Development of Vision-Based Strain Measurement Methods to Verify Finite Element Analyses

  • Kim, Hyung jong;Lee, Daeyong
    • Transactions of Materials Processing
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    • v.5 no.4
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    • pp.343-352
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    • 1996
  • One of the preferred methods that can be used to verify the results of finite element analysis is to measure surface strains of the deformed part for purpose of direct comparison with simulation results. Instead of using the usual manual method the vision-based measurement method is capable of determining surface geometry and strain from the deformed grid pattern automatically with the help of a computer. To obtain strain distribution over an area, the coordinates of such a surface grid are determined from the multiple video images by applying the photogrammetry principle. Methods to improve the overall accuracy of the vision-based strain measurement system are explored and the possible accuracies that can be attained by such a measurement method are discussed. A major emphasis is placed on the initial grid application method its accuracy and ease of subsequent image processing. Finite element analyses of limiting dome height(LDH) test are carried out and the results of them are compared with exsperimen-tal data.

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Obstacle Avoidance and Lane Recognition for the Directional Control of Unmanned Vehicle

  • Kim, Chang-Man;Moon, Hee-Chang;Kim, Sang-Gyum;Kim, Jung-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.34.6-34
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    • 2002
  • 1. Introduction 2. System Configuration 2.1 Control System 2.1.1 Longitudinal control 2.1.2 Lateral control 2.2 Sensor System 2.2.1 Photo interrupt 2.2.2 Ultrasonic sensor 2.3 Vision system 2.4 Communication system 2.4.1 Data communication 2.4.2 Image Communication 3. Test and Result 3.1 Vision test 3.2 Ultrasonic sensor test 4. Conculsion. Acknowledgment References.

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Development of Vision Technology for the Test of Soldering and Pattern Recognition of Camera Back Cover (카메라 Back Cover의 형상인식 및 납땜 검사용 Vision 기술 개발)

  • 장영희
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.119-124
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    • 1999
  • This paper presents new approach to technology pattern recognition of camera back cover and test of soldering. In real-time implementing of pattern recognition camera back cover and test of soldering, the MVB-03 vision board has been used. Image can be captured from standard CCD monochrome camera in resolutions up to 640$\times$480 pixels. Various options re available for color cameras, a synchronous camera reset, and linescan cameras. Image processing os performed using Texas Instruments TMS320C31 digital signal processors. Image display is via a standard composite video monitor and supports non-destructive color overlay. System processing is possible using c30 machine code. Application software can be written in Borland C++ or Visual C++

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Distribution of Color Vision Deficiencies by Age in Some Area of Kyeonggi-Do (경기도 일부 지역의 연령에 따른 색각장애의 분포)

  • Lee, Eun-Hee;Cho, Sung-Il;Paek, Domyung
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.3
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    • pp.307-312
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    • 2011
  • Purpose: To investigate the prevalence of congenital and age-related color vision deficiencies over a wide range of ages among residents in two urban communities of Kyeonggi-Do. Methods: A total of 935 subjects, consisting of 452 males and 483 females, participated in this study. Lanthony D-15 desaturated panels test were used to assess color vision. Results: Prevalence of color vision deficiency was 4.81% for total, 6.64% for males and 3.11% for females. Congenital color vision deficiency was 3.54% for males and 0.41% for females. Tritan deficiency, which was the post-natal age-related, was 2.99% (3.32% for males, and 2.69% for females). Conclusions: The result imply that color vision deficiencies is influenced by age. As an age-related color vision deficiencies, Tritan is most frequently found in the age group over 50.

Test of Vision Stabilizer for Unmanned Vehicle Using Virtual Environment and 6 Axis Motion Simulator (가상 환경 및 6축 모션 시뮬레이터를 이용한 무인차량 영상 안정화 장치 시험)

  • Kim, Sunwoo;Ki, Sun-Ock;Kim, Sung-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.39 no.2
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    • pp.227-233
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    • 2015
  • In this study, an indoor test environment was developed for studying the vision stabilizer of an unmanned vehicle, using a virtual environment and a 6-axis motion simulator. The real driving environment was replaced by a virtual environment based on the Aberdeen Proving Ground bump test course for military tank testing. The vehicle motion was reproduced by a 6-axis motion simulator. Virtual reality driving courses were displayed in front of the vision stabilizer, which was located on the top of the motion simulator. The performance of the stabilizer was investigated by checking the image of the camera, and the pitch and roll angles of the stabilizer captured by the IMU sensor of the camera.

Visibility Evaluation for Agricultural Tractor Operators According to ISO 5006 and 5721-1 Standards

  • Kabir, Md. Shaha Nur;Song, Mingzhang;Chung, Sun-Ok;Kim, Yong-Joo;Kim, Su-Chul;Ha, Jong-Kyou
    • Journal of Biosystems Engineering
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    • v.40 no.1
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    • pp.19-27
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    • 2015
  • Purpose: A system to measure the visibility of agricultural tractor operators was designed and evaluated according to ISO standards, and a blind area diagram around the tested tractor was created based on the manual method recommended by the National Institute for Occupational Safety and Health (NIOSH). Methods: A visibility measurement system was designed and evaluated based on the ISO 5006 and ISO 5721-1 standards. Two bulbs used to simulate the operator's eyes were mounted on a bar with a supporting frame. A wooden frame was used to determine the seat index point position. The 12-m visibility test circle was divided into six sectors of vision, and the test tractor was placed at the center of the circle. Artificial light was supplied in the darkened environment, and shadow or masking effects were measured manually around the 12-m circle. Results: When the bulbs were placed at the operator's eye level, front visibility was good; no masking was found in the "A" vision sector, but larger masking widths were found in the "B" and "C" vision sectors. Since the masking width exceeded 700 mm, additional tests, such as movement of the light sources to both sides of the operator's eye level, were performed. Less than six masking effects were found in the semi-circle of vision to the front, and more than one masking was found in the "B" and "C" visual fields. The minimum distance between the centers of two masking effects exceeded 2500 mm when measured as a chord on the semi-circle of vision. A blind area diagram was created to define the exact nature of the blind spots and mirror visibility. Conclusions: Visibility evaluation is an effective way to enable proper and safe operation for agricultural tractor operators. Inclusion of this visibility evaluation test in the general testing process might aid tractor manufacturers.

Application of deep learning technique for battery lead tab welding error detection (배터리 리드탭 압흔 오류 검출의 딥러닝 기법 적용)

  • Kim, YunHo;Kim, ByeongMan
    • Journal of Korea Society of Industrial Information Systems
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    • v.27 no.2
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    • pp.71-82
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    • 2022
  • In order to replace the sampling tensile test of products produced in the tab welding process, which is one of the automotive battery manufacturing processes, vision inspectors are currently being developed and used. However, the vision inspection has the problem of inspection position error and the cost of improving it. In order to solve these problems, there are recent cases of applying deep learning technology. As one such case, this paper tries to examine the usefulness of applying Faster R-CNN, one of the deep learning technologies, to existing product inspection. The images acquired through the existing vision inspection machine are used as training data and trained using the Faster R-CNN ResNet101 V1 1024x1024 model. The results of the conventional vision test and Faster R-CNN test are compared and analyzed based on the test standards of 0% non-detection and 10% over-detection. The non-detection rate is 34.5% in the conventional vision test and 0% in the Faster R-CNN test. The over-detection rate is 100% in the conventional vision test and 6.9% in Faster R-CNN. From these results, it is confirmed that deep learning technology is very useful for detecting welding error of lead tabs in automobile batteries.

Effect of Vision Training using Fresnel Prism Lens on Fusional Vergence and Accommodation (프레넬 프리즘렌즈를 이용한 시기능 훈련이 조절과 융합버전스에 미치는 영향)

  • Kim, Yong-Gil;Kim, Min-Kyung;Jeong, Ju-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.17 no.2
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    • pp.159-164
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    • 2012
  • Purpose: Of the various methods of vision training, the essay aims to explore the effective ways of using the Fresnel prism lens in order to expand the positive fusional vergence for the patient having specific condition of convergence insufficiency or basic exophoria. Methods: 15 students of city of Daejeon university without an eye disease (average age $22.73{\pm}1.68$) were selected and underwent the subjective refraction test and binocular vision test, and recording their test results before vision training and replacing an identical frame with a lens of same quality after the full calibration, the lens was then adhered with the Fresnel prism lens and continued to train for thirty minutes daily during two weeks. Afterwards, the binocular vision test was reattempted. The observation of the change in the results of the binocular vision test in use of the fresnel prism lens in the vision training test was researched. Results: After training, the positive fusional vergence had increased to a number of $22.27{\pm}2.26$ $\Delta$, to 7.80 $\Delta$, at near, the fused cross cylinder test increased to an average of $0.55{\pm}0.09$ D, 0.40 D after training, showing a normal result. The value of negative relative accommodation after training had an average of $2.22{\pm}0.08$D, showing that 0.42 D had increased. The value of near point of convergence after training had an average of $6.13{\pm}0.53$ cm, showing that 2.80 cm had decreased. To patients who had convergence insufficiency or basic exophoria, the value of the near vision test that used the Fresnel prism lens which was able to expand BO positive fusional vergence had increased without phoria. Conclusions: The changes were tested and the effectiveness of the Fresnel prism lens, due to the nature of the lens itself, helped with both cosmetic effects and cost. It also allows good optical correction effects, in addition to these clinical effects indicated before. Therefore, it may be determined that the Fresnel prism lens binocular vision therapy for patients is more popular and highly recommended.

The Relationship between the Segment of Erector Spinae during a Core Stability Exercise according to Visual Control (코어 안정성 훈련 시 시각통제 유무에 따른 척추세움근의 분절 간 상관분석)

  • Yoon, Jung-Gyu
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.3
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    • pp.417-424
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    • 2013
  • PURPOSE: We investigated the relationship between the segment of erector spinae during a core stability exercise according to visual control. METHODS: The subjects of this study were 20 healthy students. An 8-channel electromyograph was used to measure muscle activities of the erector spinae by segment(cervical, thoracic and lumbar) during a core stability exercise according to visual control. The collected data were analyzed using the independent t-test and Pearson-test. RESULTS: The activity of the erector spinae for all segment was higher without the vision than with. The activity of right cervical erector spinae was significantly increased by increasing the activity of the left thoracic erector spinae during a core stability exercise with vision (r= .555). The activity of left thoracic erector spinae was significantly increased by increasing the activity of the left lumbar erector spinae during a core stability exercise without vision (r= .472). CONCLUSION: There was a positive correlation between the cervical and thoracic segment of erector spinae during a core stability exercise with vision. There was a positive correlation between the thoracic and lumbar segment of erector spinae during a core stability exercise without vision.