• Journal of Korean Ophthalmic Optics Society
• /
• v.15 no.2
• /
• pp.123-130
• /
• 2010

Purpose: The study was conducted to compare the values of auto-refraction, manifest refraction and cycloplegic refraction in school-aged children. Methods: One hundred five myopic school children ranged from 6 to 14 years old (210 eyes, $10.28{\pm}1.59$ years old) were recruited and noncycloplegic auto-refraction (AR) and manifest refraction (MR) were conducted and then underwent cycloplegia and refractive status (CR) again with the auto-refractometer. Results: Refractive powers measured by AR, MR, and CR were highly correlated. However, spherical and cylindrical powers of the subjects measured by AR were measured higher negative power than in CR (p<0.001). From 210 eyes, the discrepancy rate in the spherical and cylindrical powers were 40 eyes (19%) and 19 eyes (9%) of the total subjects, respectively and the differences between noncycloplegic and cycloplegic refractions were higher with the spherical and cylindrical powers increasing. Conclusions: The use of the autorefractometer in children with negative spherical power without cycloplegia may overestimate the actual myopia that subjective refraction is the most important in prescription for the eyeglasses and regression equations would be used to prognose the cycloplegic refraction from the auto-refraction as the basic data for the subjective refraction.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.775-778
• /
• 2017

This research describes system implementation for automatic inspection on wind pressure sensor production based on reliability improvement. The reliability is minimized by the automatic inspection system on the wind pressure sensor against the manual system. The system consists of the control system and monitoring system to be scanning the inspection processing. The inspection system for reliability is evaluated in Gage Repeatability and Reproducibility. The experimental results are improved about 2 times speed, measured error ${\pm}0.02V$, effectiveness 15%, missing probability 17% and false alarm 12% respectively. The system will be also improved by database and the product barcodes for the total quality control system based on the effective reliability in the future.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.18 no.1
• /
• pp.42-45
• /
• 1998

원유 또는 가스 생산을 위해 해상에 설치되는 플랜트 해양설비는 크게 jacket과 module로 나눌 수 있다. Jacket은 module을 지지하기 위한 구조물로써 jacket 본체와 pile로 구성되어 있으며, 미국용접학회(AWS)의 규정에 의해 대부분의 맞대기 완전용접 이음부(full penetration butt welds)에 대해 100% 방사선투과검사를 실시하게 되어 있다. 그러나 지금까지 방사선투과검사를 실시해 온 경험으로 미루어 볼 때 방사성에 대한 안전성, 생산공정의 영향(검사지연) 등 방사선투과검사는 많은 문제점을 가지고 있었다. 이에 대한 문제점을 해소하고, 국내의 비파괴검사 기술 향상을 위해 자동 초음파탐상 system을 개발, 방사선투과검사를 자동 초음파탐상검사로 대체하여 적용한 사례를 간략하게 기술하였다. 또한, 적용 확대를 위해 개방중인 system을 소개하고 아울러 자동 초음파탐상기술에 대한 앞으로의 방향을 제시하였다.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.11 no.2
• /
• pp.49-57
• /
• 2002

본 연구에서는 전자부품의 자동조립라인에서 매우 중요한 작업인 열코킹 검사, 납땜 및 납땜검사 작업공정을 보다 더 정밀하고 유연하게 수행할 수 있도록 오프라인 프로그램에의 자동교시기능을 갖는 지능형 로봇 제어 시스템 개발에 대한 연구를 수행하였다. 카메라 백 카바등의 전자부품의 자동조립라인은 작업의 난이도가 매우 높고, 고정밀도가 요구되고, 특히, 납펌 및 납땜 불량검사 작업의 셀은 전체 작업 셀 공정중에서 가장 불량률이 높다. 따라서 본 연구는 기존의 납땜 및 검사공정 셀의 구조를 개선하여 보다 더 높은 정밀도를 유지할 수 있고, 모델 변경에 대한 유연성 향상 및 불량율의 감소를 통한 시스템의 신뢰성을 증대시키기 위한 목적으로 수행된다. 이의 실현을 위한 세부내용으로는 셀의 구조개선, 로봇의 모델교체 및 성능향상, 고정도의 납땜 및 검사 기술, 오프라인 프로그래밍 (off-line programming, OLP)을 이용한 자동교시기법을 개발하여 지능형 시스템으로 새로운 셀을 구성하고, 이를 실제 카메라 백 카바등의 전자부품 조립 라인에 설치하여 실시간 구현을 실현하고자 한다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2004.04a
• /
• pp.576-579
• /
• 2004

Eventhough the productivity has been improved remarkably by introducing automatic facilities, the 100％ inspection is necessary because the possibility to produce large amount of defective goods is also increased. Since it is extremely unreasonable that workers inspect very large amount of products as 100％ inspection, there has been many researches for the automatic inspection system. In this thesis, we develop an automatic detection system of suspension insulator's minutes cracks System The automatic detection system of suspension insulator's minute cracks： To detect the minute cracks of suspension insulators, images of the insulator are acquired with a progressive scan camera, rotating a suspension insulator on a turning table. And after the shadow and noises are eliminated by preprocessing techniques, we detect minute cracks using the features of them.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.17 no.2
• /
• pp.114-121
• /
• 1997

가압경수로 원자로 압력용기 비파괴검사를 위해 지금까지 계속 사용하여 온 기존의 고정식 매니플레이터 방식의 원자로 자동초음파검사장비는 최근 급속도로 발전한 전자산업 및 컴퓨터 등으로 인해 기본 설계 개념부터 달리하는 소형.경량화된 수중 이동형 원자로 검사 장비 형태로 바뀌어 가고 있다. 따라서, 본 해설에서는 현재까지 국내외 알려진 각종 소형 원자로 압력용기 자동초음파검사장비 및 고정식 매니플레이터 방식의 원자로 압력용기 자동초음파검사장비를 분석하여 기술하였으며, 현재 국내 원자로 압력용기 용접부검사를 위해 개발중인 RYSIS 장비 및 검사 기술 수준을 진단해보고 앞으로의 방향을 제시하였다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2005.07b
• /
• pp.862-864
• /
• 2005

자동차 전자 부품 중 하나인 정션박스의 자동 시각 검사 시스템은 사랑의 육안 검사를 자동화함으로써, 정확하고 빠른 검사가 가능하다. 또한 검사 결과를 데이터베이스화하여 지속적인 불량 발생요인을 분석할 수 있기 때문에 불량률을 감소시켜 제품 신뢰도를 향상시킬 수 인다. 본 연구에서는 정션박스에 삽입된 퓨즈와 릴레이의 유무 및 오결합을 자동으로 검사하는 자동 시각 검사 시스템을 구현하였고 이를 적용한 결과 신속하고 정확한 검사가 가능함을 보였다.

• Journal of Korean Ophthalmic Optics Society
• /
• v.15 no.1
• /
• pp.99-104
• /
• 2010

Purpose: Difference of refraction result from the method of autorefraction and iTrace were investigaged for the children of elementary school in Asan City. In iTrace method. exclusion of accommodation without cycloplegia was used. Methods: Manifest refractive stale of 42 eyes of 12~13 years old were measured using autorefractor and iTrace. Refractions of far (more than 5 m) and ncar (30 cm) vision were measured using iTrace. All data showed that the spherical equivalent were classified as being in the group 1 (-0.50D < ~ < +1.00D) and 2 (below -0.50D) according 10 refractive errors. Results: Mean spherical equivalent using autorefractor and iTrace (far and near vision) were -1.08D, -0.29D and -2.34D, respectively (p<0.01). Compared with the far vision using iTrace, autorefraction was measured the myopia with -0.50D ~ -1.00D in 52.4% of total eyes. Autorefraction also statistical significant were measured a more myopia than the far vision using iTrace in group I and 2. Conclusions: The difference of refractive errors between autorefraction and iTrace, objective refraction were measured with far vision of more than 5 m were -0.79D. Autoreftaction showed statistically decreased refraction errors than iTrace with far vision.

• Nuclear industry
• /
• v.23 no.3 s.241
• /
• pp.42-48
• /
• 2003

가압 경수로는 원통형의 원자로 용기 안에서 핵물질을 반응시켜 고온$\cdot$고압의 물을 생성하는데 이 원자로 용기는 환형 주조물들을 서로 용접하여 만들어진다. 이 원자로 용기의 건전성을 확인하기 위해서는 용접부위에 결함이 발생되었는지를 주기적으로 정확하게 검사해야 한다. 한국원자력연구소는 원자력발전소의 핵심 기기인 원자로 용기의 용접부 결함을 수중에서 자동으로 검사, 탐지할 수 있는 $\ulcorner$원자로 자동 탐상 시스템$\lrcorner$을 개발하여, 울진 원전 6호기용 원자로 용기에서 실증 실험을 수행하였다. 이 원자로 자동 탐상 시스템은 물방개처럼 생긴 수중 탐상 로봇이 그 핵심으로서 이 로봇은 원자로 용기의 내벽을 타고 다니면서 수중 초음파 검사를 수행할 수 있는 획기적인 시스템이다. 본고에서는 개발된 원자로 자동 탐상 시스템을 소개하고자 한다.

• Journal of Korean Ophthalmic Optics Society
• /
• v.21 no.2
• /
• pp.119-126
• /
• 2016

Purpose: To analyze the effect of accommodative control and change values between subjective refraction (SR) and auto-refraction (AR) according to application of fogging after accommodative stimulation depending on ametropia type. Methods: Myopic ametropia 76 eyes and hyperopic ametropia 52 eyes participated for this study. SR and AR values measured by three test conditions (Before accommodative stimulation; Before AS, After accommodative stimulation; After AS, and After application of fogging; After AF) were compared, respectively. Results: In myopic eyes, (-)spherical power by SR and AR in After AS test was significantly increased as compared to Before AS test, (-)spherical power in After AF test was decreased to the level of Before AS test. The differences of spherical power between SR and AR were highly measured by SR in After AS test, and highly measured by AR in After AF test, respectively. In hyperopic eyes, (+)spherical power of SR significantly decreased in After AS test compared to Before AS test, more (+)spherical power was detected in After AF test compared to Before AS test. (+)spherical power of AR have no significant difference between Before AS and After AS test, but more (+)spherical power was detected in After AF test compared to Before AS test. The differences of (+)spherical power between SR and AR were significant in all test conditions. Among 52 eyes which were measured as hyperopic ametropia, 7 eyes were measured as myopia by SR in After AS test. In case of AR, 25 eyes among 52 eyes were mismeasured as myopia of ranges from -0.25 D to -1.25 D in Before AS test, 26 eyes in After AS test, and 19 eyes in After AF test were mismeasured as myopia of ranges from -0.25 D to -1.25 D. Conclusions: Regardless of ametropia type, accommodative control by After AF test was effective on both refraction process. However, in auto-refraction for hyperopic eyes, the misdetermined proportion of refractive error's type was high due to consistent accommodative intervention in all test condition. Therefore, in order to obtain an accurate value of refractive errors, full correction should be determined by subjective refraction process after fogging method.