• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1461_1462
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• 2009

송전선로에 설취된 애자들은 지속적인 전기적 기계적 스트레스에 노출되어 있기 때문에 여러 환경적 요인으로 인해 애자 표면의 열화가 가속된다. 이와 같은 애자의 표면 열화는 dryband를 형성하게 되고 지속적인 애자 표면상의 dryband와 누설 전류 증가의 상호작용은 애자의 섬락를 일으키는 원인이 된다. 이러한 연구의 결과 고전압용 애자로 유입되는 누설 전류는 애자 열화의 정도를 평가할 수 있는 매우 중요한 parameter임을 알 수 있다. 따라서 고전압용 애자의 누설전류를 분석하고 취득하여 애자의 열화 평가 및 이로 인해 발생할 수 있는 결함 애자의 검출에 대한 연구가 절실히 요구되고 있다. 본 논문에서는 고전압용 애자 중 자기애자의 습도변화에 따른 누설전류 특성을 조사하기 위해 자체 제작한 실험 챔버, power transformer, 전류센서, 오실로스코프, PC등으로 구성된 실험 시스템을 구축하였고, 데이터 분석을 위한 S/W로서 LabView를 사용하였다. 그에 따른 실험결과로서 다양한 습도변화(30%~90%)의 경우 정상 애자련과 결함 애자를 포함한 애자련의 누설전류 데이터를 취득하여 본 연구에서 제시한 알고리즘을 통해 분석함으로써 정상 애자 내의 결함 애자 포함 여부를 판별하고 다양한 습도 변화시에 정상 애자련과 불량 애자련의 특징을 볼 수 있었다.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.5
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• pp.183-190
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• 2013

In this paper, we propose an improved anisotropic diffusion model for micro-crack detection in heterogeneously textured surface of polycrystalline solar wafers. Due to the nature of the image sensor, the gray-level of the diagonal micro-crack is non-uniform. Thus, the conventional algorithms can't fully detect diagonal micro-cracks when the number of iteration is not enough. However, the increasing of the iteration number leads to increase computation time and detects micro-crack thicker than the original micro-crack. In order to overcome this drawback, we use the gradient of north, south, east, and west directions as well as extended directions. To calculate the diffusion coefficients, we compare the gradients of conventional directions and extended directions and apply the larger gradient values to the coefficient function. This is because the proposed method reflects the information of diagonal micro-crack. Comparing to Tsai et al.'s and Ko and Rheem's, the proposed algorithm shows superior efficiency in detecting the diagonal micro-cracks with less iterations in the images of polycrystalline solar wafers. In addition, it also shows that the thickness of segmented micro-crack is similar to the orignal micro-crack.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.1807-1812
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• 2014

A plastic has a various advantages in engineering elements that it can be formed a curve surface without restriction of shape and product the high volume with various color and lower price. Also, it is being used for many parts of automobile as the weight of cars is getting lighter. The Door A-Fuel Filler is a automobile plastic part by injection molding production. The injected products are involved a lot of factors for the inferior goods after painting. Therefore the painted products are required to have the process of the polishing in order to eliminate the faults. Now polishing process is being worked by hands. The workers tend to evade the process of polishing because the working needs a lot of powers momentarily. This paper presents the development of auto-polishing system that can check the inferior goods by the vision system and control the polishing process by the motion system. As a result, Shorten production time (30 seconds), and decreases by 1 person to work to increase the competitiveness of the production cost was to expect improvement.

• Journal of Korea Multimedia Society
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• v.13 no.3
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• pp.392-399
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• 2010

The Automobile has developed and changed through the years from the invention and increased human-being's scope of activity. Junction Box, one of the part of automobile, is inspected by human eyes which caused mistakes and slow progress. To achieve the speed and accuracy the system was compensated by vision system which is inspecting automatically. This paper is automatic inspection of fuse and relay which is inserted in the junction box by checking the color and pattern of the cover. After checking the performance of the system by using the junction box, the result was 100 percent perception and open the possibility to inspect junction box fast and easy and accurate if it is applied to the industry.

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.7-12
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• 2018

In today's rapidly growing contemporary society, there is a tendency for demand to automate production processes by utilizing the vision system. In general, image recognition is mainly concerned with embossed characters such as license plates, and research on recognition of intaglio characters is very limited. Especially, intaglio characters, which are marked on rubber related products such as tire surfaces, have difficulty in recognizing characters or numbers through image because the difference in brightness with surrounding is not so large. In this paper, we propose a system to improve the recognition rate of characters marked on intaglio rubber products such as tire surfaces. Also, it can be applied flexibly according to the lighting environment. Through the proposed system, production and inventory management and defect detection can be processed quickly by applying to the production process of tire and rubber products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1653-1660
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• 2004

This study was conducted to investigate seasonal changes of microbiological counts and sanitation state on the surface of food service facilities and utilities of elementary schools in Busan area. Samples swabbed using sponge were collected from the surface of food service facilities and utilities, that is ceiling, wall, floor, trench, grease trap, hood, pest control net and dumb waiter, and analyzed by measuring the total plate, coliform and Salmonella spp. count. The total plate counts at foodservice facilities and utilities except ceiling and wall were ranged from 10$^4$∼10$^{6}$ CFU/100 $\textrm{cm}^2$. The coliform counts were ranged from 10$^2$∼10$^4$ CFU/100 $\textrm{cm}^2$ at foodservice facilities and utilities except ceiling. The grease trap was the severely contaminated facility. It was indicated that the sanitary condition at the foodservice facilities and utilities except ceiling and wall should be improved promptly. As a result of investigating the seasonal changes of microbiological counts, floor, trench, grease trap and dumb waiter should be carried out disinfection before foodserving everyday in summer season, and the disinfection frequencies of wall, hood and pest control net should not be less than three times per week. In winter season floor, trench, and dumb waiter should be carried out disinfection after foodserving, grease trap should be carried out disinfection before foodserving everyday and the disinfection frequencies of wall, hood and pest control net should not be less than twice per week.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.2
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• pp.411-416
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• 2019

In this paper, we describe a measurement system based on vision for detecting the rotation axis of dimpled golf ball. Some golf balls have wrong rotation axis owing to bad production and scratch. A flying golf ball makes sliced or curved motion mainly to owing the wrong rotation axis of golf ball. Dimples of golf ball make a golf ball higher and more straight flying. When we hit a golf ball by driver or iron club, the dimpled ball flies straight and rotates as well. While the ball flying, the rotating axis of the ball convergence. And this makes the ball motion curved. If we hit a golf ball in direction of the rotation axis, the flying ball makes straight motion. In this paper, we develop a control system to detect convergence axis and time of flying golf ball based on vision system. To show validity of the developed system, We experimented several case for dimpled golf balls.

• Clean Technology
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• v.19 no.3
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• pp.264-271
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• 2013

In this study, we optimized the removal condition of contaminants attached on the scrap surface to recycle the scrap generated from the Zr alloy tube manufacturing process back to the nuclear grade. The main contaminant is remnant of watersoluble cooling lubricant that is used in the pilgering manufacture during the tube production, and it is assumed to be compressed and carbonized on the surface of tube. Zirlo alloy tube of ${\phi}9.50mm$, which has high occurrence frequency of scrap, was selected as the object to be cleaned, and cleaning abilities of reagents were evaluated by measuring the characteristics of contaminants remained and by analyzing the surface of the tube after cleaning process. For evaluation of each cleaning agent, we selected two types of sodium hydroxide series and three types of potassium hydroxide series. Furthermore, to confirm dependence on tempe-rature and ultrasonic intensities, cleaning at the room temperature, $40^{\circ}C$, and $60^{\circ}C$ was conducted, and results showed that higher the cleaning temperature and higher the ultrasonic intensity, better the cleaning effect. As a result of the bare-eye inspection, while the use of sodium hydroxide provided satisfactory condition on the tube surface, the use of potassium hydroxide series provided satisfactory condition on the tube surface only when the ultrasonic intensity was over 120 W. In the cleaning effect analysis using the gravimetric method, cleaning efficiency of sodium hydroxide series was as high as 97.6% ($60^{\circ}C$, 120 W), but since the tube surface condition was poor after the use of potassium hydroxide, the gravimetric method was not appropriate. In the analytical result of surface contaminants on the tube surface, C, O, Ca, and Zr were detected, and mainly C and O dominated the proportion of contaminants. It was also found that the degree of cleaning on the tube affected the componential ratio of C and O; if the degree of cleaning is high, or if cleaning is well-conducted, the proportion of C is decreased, and the proportion of O is increased. Based on these results, optimal cleaning for application in the industry can be expected by categorizing cleaning process into three steps of Alkali cleaning, Rinsing, and Drying and by adjusting cleaning parameters in each step.

• Korean journal of food and cookery science
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• v.25 no.3
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• pp.365-378
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• 2009

This study performed microbiological hazards analysis in raw food materials, cooking processes, kitchen staff, utensils, and the environment in order to obtain contamination levels of S. aureus in school foodservice operations. S. aureus was not detected in cooked foods offered by the foodservice operations; however, it was found in raw food materials prior to cooking. In the case of vegetables, S. aureus was detected in washed mung bean sprouts, parboiled mung bean sprouts, and bellflower roots both before and after disinfection, at levels of 2.2, 1.0, 1.0, and 1.0 log CFU/g, respectively. For processed foods, S. aureus was detected in one sample of packaged bean curd as well as in mung bean jelly cake at the level of 1.5 log CFU/g. For meat products, S. aureus was detected in beef brisket and chicken at levels of 2.3 and 1.3 log CFU/g, respectively. To determine microbiological hazard data for the hands and gloves of cooking personnel, the staff members were divided into two groups: a group presenting Enterobacteriaceae or coliforms, and another group presenting neither Enterobacteriaceae nor coliforms. The results showed that S. aureus was detected on the hands of staff in each group at levels of 2.0 and 2.1 log CFU/hand, respectively, and at 1.8 and 0.0 log CFU/hand on the gloves of staff in each group, respectively. Among kitchen utensils, as an environmental factor in school foodservice operations, S. aureus was detected on meat knives, mixing bowls, and dish cloths at levels exceeding 1.0 log CFU/hand.