• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.466-469
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• 1998

The electronic fluorescent lamp ballast can promote the lighting efficiency up to 10-20% by driving high frequency with frequency transformation technique, and can completely eliminate the flickering phenomenon occurring from 60Hz frequency. The electronic ballast provides very high energy saving effects for it has high power fact than traditional ballast, and it is convenient to use. can extend the life of fluorescent lamp for it starts at once by driving with high frequency. However electronic ballast needs high price, and it can reduce the stability and reliability. This paper provides illumination systems which drive dozens of fluorescent lamps at the same time, to overcome these shortcomings of electronic ballast and utilize the advantage of electronic ballast.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.998-1002
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• 1998

The electronic fluorescent lamp ballast can promote the lighting efficiency up to 10-20% by driving high frequency with frequency transformation technique, and can completely eliminate the flickering phenomenon occurring from 60Hz frequency. The electronic ballast provides very high energy saving effects for it has high power factor than traditional ballast, and it is convenient to use, can extend the life cycle of fluorescent lamp for it starts at once by driving with high frequency. However electronic ballast needs high price, and it has the bad stability and reliability. This paper provides illumination systems, which drive dozens of fluorescent lamps at the same time, to overcome these shortcomings of electronic ballast and utilize the advantage of electronic ballast.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.5
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• pp.473-479
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• 2009

This paper proposes an efficient method to locate the automated guided vehicle (AGV) into a specific parking position using artificial visual landmark and vision-based algorithm. The landmark has comer features and a HSI color arrangement for robustness against illuminant variation. The landmark is attached to left of a parking spot under a crane. For parking, an AGV detects the landmark with CCD camera fixed to the AGV using Harris comer detector and matching descriptors of the comer features. After detecting the landmark, the AGV tracks the landmark using pyramidal Lucas-Kanade feature tracker and a refinement process. Then, the AGV decreases its speed and aligns its longitudinal position with the center of the landmark. The experiments showed the AGV parked accurately at the parking spot with small standard deviation of error under bright illumination and dark illumination.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.239-240
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• 2013

The quality of document images captured by digital camera might be degraded because of non-uniform illumination condition. The high illumination (glare distortion) affects on the contrast condition of the document images. This condition leads to the poor contrast condition of the text in document image. So, optical character recognition (OCR) system might hardly recognize text in the high illuminated area. The method to increase the contrast condition between text (foreground) and background in high illuminated area is proposed in this paper.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.7
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• pp.1391-1395
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• 2011

In this paper, would implement a transceiver for the visible light communication that based on wireless communication driving technology for LED illumination-based infrared ray communication, and measurement analyzed a design error rate of a transceiver variable rate has made about distance change -2.5m. The error rate measured a voltage variable along illuminate change between switchable circumstances, which has illuminated insight and outright. Each analyzed and measurement on the communication distance errors along the differences of disturbance light between night and days. The LED module has implemented for number of 6 through illumination dimming in case of different values. Also, implementation for the system module of a VLC transceiver based on the infrared sensors which used feedback outcome value has analyzed with error rate.

• Journal of Information Processing Systems
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• v.14 no.6
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• pp.1307-1317
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• 2018

To deal with the problems of occlusion, pose variations and illumination changes in the object tracking system, a regression model weighted multi-templates mean-shift (MS) algorithm is proposed in this paper. Target templates and occlusion templates are extracted to compose a multi-templates set. Then, the MS algorithm is applied to the multi-templates set for obtaining the candidate areas. Moreover, a regression model is trained to estimate the Bhattacharyya coefficients between the templates and candidate areas. Finally, the geometric center of the tracked areas is considered as the object's position. The proposed algorithm is evaluated on several classical videos. The experimental results show that the regression model weighted multi-templates MS algorithm can track an object accurately in terms of occlusion, illumination changes and pose variations.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.1
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• pp.1-11
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• 1997

Austomated visual inspection(AVI) capability has become an important key component in the automated manufacturing system. In such a visual inspection system an intensity(or color) image of a scene is quickly affected by optical property of objects, condition and roughness of surface, lens and filters, image sensor property and lighting system. In particular, the lighting system disign is the most important factor, since it affects overall performance of the visual system. For fast and cheap automated visual inspection system it is important to obtain the good image quality which results from careful attention to the design of the lighting system. In this paper, the lighting subsystem of AVI system is analysed for the inspection of printed circuit board(PCB) patterns. The spectral reflectance of materials, which are composed of PCB, is measured for choosing the light source. The reflection property is theoretically obtained by a reflection model and also obtained by experiments which measure intensity with varying the viewing direction of image sensor and the lighting direction of illuminator. The illumination uniformity of a ring-type illuminator. The lighting system is designed based upon the experimental results and theoretial analysis.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.769-772
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• 1998

This paper present an efficient techniques for visual inspection of taped electronic parts, suitable for real time implementation. The main environments of developed system are IBM-compatible personal computer, frame grabber, digital input-output board. It is connected to the programmable logic controller unit of the taping machine in real time. Using a queuing structure, operator or extractor machine can remove easily the defect one from production line. Also, we design a new illumination system for sacquring shape and subface features of object. Therefore, it redue pre-processing step and processing time.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1998.06b
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• pp.45-50
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• 1998

Several 3 dimensional image display systems were recently developed in Korea. These are a holographic video system based on pulse laser illumination, ad 8-view 3 dimensional image system capable of displaying computer generated 3 dimensional images and multiview 3 dimensional imaging system based on moving aperture and holographic screens of both transmission and reflection types. All these systems require no special glasses to watch and works impressively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1523-1524
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• 2013