• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.4
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• pp.206-213
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• 2011

Line sleeves, which used to connect ACSR cables when transmission lines were constructing, sometimes cause power transmission failure due to deterioration and corrosion. Therefore, power transmission line should be inspected regularly to prevent national disaster. Current inspection tool detects insertion length of transmission line on line sleeves, the inspection tool includes enormous error by operator. Moreover, the system is not controlled remotely, negligent accident would be caused while inspecting. To deal with those problems, KEPCO reviewed several ways to inspect line sleeves and proposes new method to inspect line sleeve by measuring magnetic flex which penetrate junction of steel and aluminum sleeve. The developed inspection tool is reliable enough to detect eccentric sleeves. Also, the developed inspection device was applied on actual transmission line and verified its effectiveness.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.194-198
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• 2012

This paper describes flying inspection apparatus for 22.9kV distribution line. This apparatus is composed of multi-copter(more than 4 propellers), camcorder and remote controller. The existing inspections, such as hot-line inspection job and optical inspection method and distribution Line Checking Robot, have many restrictions. A electric working vehicle and hot-line job license are essential in hot-line inspection job. Besides its high cost, it can't be applied to the electric pole over 18m and road-blocked area. Optical method can't inspect upper side of electric facilities mounted on the electric pole. Robot method can't be applied to the corroded overhead earth wire and nothing of overhead earth wire. To solve the problems, in Korea Electric Power Co., we have applied flying inspection apparatus to the 22.9kV distribution line. The results of trial application show that this paper is practical and effective for the inspection technical method in 22.9kV distribution line

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.3
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• pp.18-23
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• 2006

The formation degree of sustain (ITO pattern) determines the quality of a PDP (Plasma Display Panel). Thus, in the present study, we attempt to detect 100% of the defects that are larger than $30{\mu}m$. Currently, the inspection method in the PDP manufacturing process is dependent upon the naked eye or a microscope in off-line mode. In this study, a prototype inspection system for PDP ITO patterned glass is developed. The developed system, which is based on a line-scan mechanism, obtains information on the defects and sorts the defects by type automatically. The developed inspection system adopts a multi-vision method using slit-beam formation for minimum inspection time and the detection algorithm is embodied in the detection ability. Characteristic defects such as pin holes, substances, and protrusions are extracted using the blob analysis method. Defects such as open, short, spots and others are distinguished by the line type inspection algorithm. It was experimentally verified that the developed inspection system can detect defects with reliability of up to 95% in about 60 seconds for the 42-inch PDP panel.

• Industrial Engineering and Management Systems
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• v.8 no.3
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• pp.131-138
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• 2009

The variable sampling inspection scheme with screening for the purpose of assuring the upper limit of maximum expected surplus loss after inspection has been proposed. In this inspection scheme, it has been assumed that a product lot consists of products manufactured through a single production line and lot quality characteristics follow a normal distribution. In the previous literature with respect to inspection schemes, it has been commonly assumed that lot quality characteristics obey a single normal distribution under the condition that all products are manufactured in the same condition. On the other hand, the production line is designed in order that the workload of respective processes becomes uniform from the viewpoint of line balancing. One of the solutions for the bottleneck process is to arrange the workshops in parallel. The lot quality characteristics from such a production line with the process consisting of some parallel workshops might not follow strictly the single normal distribution. Therefore, we expand an applicable scope of the above mentioned variable sampling inspection scheme with screening in this article. Concretely, we consider the variable sampling inspection with screening for the purpose of assuring the upper limit of average outgoing surplus quality loss in the production lots when the lot quality follows the mixed normal distribution.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.191-195
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• 2003

The formation degree of sustain (ITO pattern) decides quality of PDP (plasma display panel). For this reason. it makes efforts in search defects more than 30 ${\mu}{\textrm}{m}$. Now, the existing inspection process is dependent upon naked eye or SEM equipment in off-line PDP manufacturing process. In this study developed prototype inspection system of PDP ITO glass. This system creates information that detects and sorts kind of defect automatically. Design ed inspection technology adopts line-scan method by slip-beam formation for the minimum of inspection time and image processing algorithm is embodied in detection ability of developed system. Designed algorithm had to make good use of kernel matrix which draws up an approach to geometry. A characteristic of area-shaped defects, as pin hole, substance, protrusion et al, are extracted from blob analysis method. Defects, as open, short, spots, et al, are distinguished by line type inspection algorithm. In experiment results, we could have ensured ability of inspection that can be detected with reliability of up to 95% in about 60 seconds

• Journal of the Korean Operations Research and Management Science Society
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• v.18 no.1
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• pp.97-117
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• 1993

This paper considers inspection station location problem for a flexible assembly line that consists of multiple stages. By considering the trade-off between locating an station at an "early" stage and at a "late" stage, we have developed some dominance relations on a graph. Based on the dominance relations, we then present an algorithm that finds an optimal inspection plan and a heuristic approach that finds a near-optimal inspection plan. The effectiveness of these two algorithms is demonstrated by two numerical examples. numerical examples.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.88.3-88
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• 2001

In this paper, an on-line multi-sensor visual inspection technique for seamless steel pipe´s straightness is developed. The basic principle of the visual measuring method is detailed. The modeling of visual sensor, measurement system and data processing are presented. In order to test the accuracy of the multi-sensor visual inspection, an experiment inspecting the straightness of a 1500mm long seamless steel pipe is made. The experiment results show that the visual inspection technique can achieve on-line measurement and offers high precision and stability.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.10
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• pp.28-34
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• 1997

This paper describes an automatic measurement method for the in-line inspection of assembly tolerances of cathod ray electron guns. The method uses an optical microscope with a CCD camera as a probe. An automatic gap recognition algorthm with digital image processing and a new software autofocus algorithm based on using an optimal edge detector have been developed to improve the measuring accuracy. An inspection system has been proposed and practically implemented for in-line inspection to a real factory automation line. The inspection system consists of a gap inspection part and an eyelet. Total time consumed for inspecting all measuring items is about 10 seconds and the repeatability is below .+-. 5 .mu. m

• Journal of the Korean Society for Precision Engineering
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• v.21 no.12
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• pp.92-99
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• 2004

The formation degree of sustain (ITO pattern) decides quality of PDP (Plasma Display Panel). For this reason, it makes efforts in searching defects more than 30 un as 100%. Now, the existing inspection is dependent upon naked eye or microscope in off-line PDP manufacturing process. In this study developed prototype inspection system of PDP 170 glass is based on line-scan mechanism. Developed system creates information that detects and sorts kinds of defect automatically. Designed inspection technology adopts multi-vision method by slip-beam formation for the minimum of inspection time and detection algorithm is embodied in detection ability of developed system. Designed algorithm had to make good use of kernel matrix that draws up an approach to geometry. A characteristic of defects, as pin hole, substance, protrusion, are extracted from blob analysis method. Defects, as open, short, spots and et al, are distinguished by line type inspection algorithm. In experiment, we could have ensured ability of inspection that can be detected with reliability of up to 95% in about 60 seconds.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.11
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• pp.61-68
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• 2004

Recently, there has been an increasing demand for computer-vision based inspection and/or measurement system as a part of factory automation equipment. Existing manual inspection method can inspect only specific samples and has low measuring accuracy as well as it increases working time. Thus, in order to improve the objectivity and reproducibility, computer-aided analysis method is needed. In this paper, front and side profile inspection and/or data transfer system are developed using computer-vision during the inspection process on three kinds of pipes coming from a forming line. Straight line and circle are extracted from profiles obtained from vision using Laplace operator. To reduce inspection time, Hough Transform is used with clustering method for straight line detection and the center points and diameters of inner and outer circle are found to determine eccentricity and whether good or bad. Also, an inspection system has been built that each pipe's data and images of good/bad test are stored as files and transferred to the server so that the center can manage them.