• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.10 no.5
• /
• pp.359-363
• /
• 2017

The LED (Liquid Emitting Diode) frame device is a big part of the representative display industry in Korea. LED is an essential part for TV, monitor, notebook, and mobile phone. In Japan, Taiwan, China and other countries, investment in LEDs has been strengthened, and productivity has become an important issue. However, as the size of the parts becomes smaller, the inconsistent inspection by the human eye becomes a problem of reliability, so that the automatic inspection process becomes an essential issue in the field of LED module inspection. In this paper, we investigate defects in visual inspection process using computer vision technology. The inspection of the LED frame is made quickly and accurately, thereby improving the efficiency of the process and shortening the inspection time. As a result of applying the inspection system to the field, we confirmed that it is possible to inspect quickly and accurately.

• Journal of The Korean Association For Science Education
• /
• v.18 no.4
• /
• pp.545-555
• /
• 1998

The improvement of process skills has been one of the most important goals in secondary science education. To achieve this goal, it is essential to develop an instrument for evaluating inquiry skills in addition to improving science curricula, inquiry teaching methods, and other educational environment. There are a lot of instruments in testing science process skills in Korea as well as America and Europe. However, it has been difficult to find the instruments that have a characteristic in content and form. The purpose of this study is to develop a valid and reliable instrument for evaluating science process skills using line graph. This study examined the whole body of scientific process and identified 6 component skills. Three or four items for each component process skills were developed and revised by pilot test and field test. The instrument is considered valid and reliable, for the content validity is 78% and the reliability(KR-20) is 0.82. The discrimination index is 0.57 and difficulty index is 0.47, which also suffice the criteria of good test.

• Journal of the Korea Society of Computer and Information
• /
• v.29 no.10
• /
• pp.149-156
• /
• 2024

This paper implemented a drill bit foreign matter inspection system based on the YOLO V3 algorithm and evaluated its performance. The study trained the YOLO V3 model using 600 training data to distinguish between the normal and foreign matter states of the drill bit. The implemented inspection system accurately analyzed the state of the drill bit and effectively detected defects through automatic inspection. The performance evaluation was performed on drill bits used more than 2,000 times, and achieved a recognition rate of 98% for determining whether resharpening was possible. The goal of foreign matter removal in the cleaning process was evaluated as 99.6%, and the automatic inspection system could inspect more than 500 drill bits per hour, which was about 4.3 times faster than the existing manual inspection method and recorded a high accuracy of 99%. These results show that the automated inspection system can dramatically improve inspection speed and accuracy, and can contribute to quality improvement and cost reduction in manufacturing sites. In future studies, it is necessary to develop more efficient and reliable inspection technology through system optimization and performance improvement.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2007.04a
• /
• pp.17-21
• /
• 2007

Ultrasonic inspection method is more profitable than X-ray radiographic inspection in cost and effect of defect detection such as debond, and it doesn't need special facilities. The method can also be a possible real time inspection with safety. This report explains the experiment and theoretical modeling analysis of the inspection methods of propellant/liner debond using ultrasonic multi-reflection in rocket motor. From the results, it is possible to detect the defect of propellant/liner debond and its signal is distinguishable with normal. And, it is approximately coincide with both experimental signal and modeling.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.28 no.4
• /
• pp.339-345
• /
• 2008

The heat exchanger tube in nuclear power plants is mainly fabricated from nonferromagnetic material such as a copper, titanium, and inconel alloy, but the moisture separator & reheater tube in the turbine system is fabricated from ferromagnetic material such as a carbon steel or ferrite stainless steel which has a good mechanical properties in harsh environments of high pressure and temperature. Especially, the moisture separator & reheater tubes, which use steam as a heat transfer media, typically employ a tubing with integral fins to furnish higher heat transfer rates. The ferromagnetic tube typically shows superior properties in high pressure and temperature environments than a nonferromagnetic material, but can make a trouble during the normal operation of power plants because the ferrous tube has service-induced damage forms including a steam cutting, erosion, mechanical wear, stress corrosion cracking, etc. Therefore, nondestructive examination is periodically performed to evaluate the tube integrity. Now, the remote field testing(RFT) technique is one of the solution for examination of ferromagnetic tube because the conventional eddy current technique typically can not be applied to ferromagnetic tube such as a ferrite stainless steel due to the high electrical permeability of ferrous tube. In this study, we have designed RFT probes, calibration standards, artificial flaw specimen, and probe pusher-puller necessary for field application, and have successfully carry out RFT examination of the moisture separator & reheater tube of nuclear power plants.

• 월간 기계설비
• /
• s.294
• /
• pp.68-80
• /
• 2015

'가구업계의 공룡'인 이케아가 한국에 상륙했다. 지난해 12월 18일 경기도 광명시 KTX역 인근에 첫 한국매장을 연 후 하루 3만명 이상의 인파가 운집하는 등 연일 화제를 뿌리고 있다. 10년 전만 해도 사람들의 발길이 잘 닿지 않았던 이 지역은 KTX 광명역 개통 후 주로 기차 승객들이 왕래했으나 최근 코스트코 광명점과 광명종합터미널, 롯데 프리미엄아웃렛이 개장되면서 점차 활기를 띄고 있으며, 이케아 광명점 개장을 계기로 경기도권 최대의 쇼핑특구로 성장할 전망이다. 이케아는 지난 1943년 스웨덴에서 설립된 이래 전세계 40개국 340여개 매장에서 가구뿐만 아니라 벽시계, 가방 등 인테리어 소품까지 약 9,500여 종의 물품을 판매하고 있으며, 전세계 직원수 15만명, 매장당 평균 매출 약 1,200억원에 이르는 다국적 대기업이다. 이케아는 또 유럽에서 눈부시게 성장하고 있는 에너지 기업 가운데 하나다. 전 세계에 풍력발전기 96대를 직접 설치해 전기를 생산한다. 또한 광명점에 3,000개를 비롯해 전 세계 100여개 매장에 태양광 패널 55만개를 설치했다. 생산된 전기는 공장과 매장에서 쓴다. 본지는 지난 해 11월 말 준공검사를 끝내고 개장 준비로 분주한 이케아 현장에서 기계설비 및 소방공사를 담당한 (주)정도설비 이대호 현장소장과 시공사인 대림산업의 공화석 설비부장을 만났다.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.379-380
• /
• 2013

• 한국가스학회:학술대회논문집
• /
• 2005.10a
• /
• pp.44-48
• /
• 2005

• Journal of the KSME
• /
• v.28 no.4
• /
• pp.387-393
• /
• 1988

본 SP시험법은 사용되는 시편이 미소하다는 장점 때문에 재질의 평가나 더불어 비파괴검사의 일환으로서 이용할 수 있음을 서명해 왔다. 현존하고 있는 거대구조물들의 잔존수명평가가 요 구되는 있는 지금, 정량적인 경년변화측정방법으로서 SP시험법은 높은 가능성을 내포하고 있는 시험법으로 여겨지며, 이 방법을 현장에 정착시키기 위해선 산. 학. 연의 공동연구체제가 필요 하다고 할 수 있다.

• KOREAN POULTRY JOURNAL
• /
• v.39 no.4 s.450
• /
• pp.100-103
• /
• 2007

국내 수의과대학 조류질병학 실험실은 사육농가에서 발병하는 질병의 원인체 분석, 예방을 위한 백신관련연구 등 낮은 질병피해로 사양성적을 향상시키기 위해 필드 양축가와 밀접한 관계를 유지하고 있다. 이와 관련하여 본지에서는 가검물 혈청 검사로 국내 양계질병분석을 담당하는 충북대학교 수의과대학 모인필 교수를 찾아 양축가를 위해 실험실에서 다루는 내용을 들어보았다.