• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.55-63
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• 2002

Meet in the internationalization period recently and van every county is progressing unionization work of every county standard with the Europe, the United States of America. If our county does not correspond actively by age, economical disadvantage is expected. Tested PC, PC monitor, printer and harmonic for device for company business of FAX 4 kinds and flicker occurrence disgrace to achieve and analyze electricity quality test for office appliances by link of confrontation in such current in treatise that see therefore. As result that test printer and PC monitor ware stable but Desktop PC and FAX are presented in valid EN standard to January, 2004 that more than limit higher harmonics and flicker phenomenon appeared, and presented countermove in reply.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.1
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• pp.94-99
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• 1997

There are several factors that have influence on the phase noise of an oscillator. But one of the major factors is the flicker noise of a transistor, since the phase noise of an oscillator is generated by mixing the carrier with the low frequency noise near the DC having the characteristic of 1/f. In this paper, we have presented a method on reducing the phase noise of an oscillator by using a low-frequency feedback circuit based on an active bias circuit, and have fabricated a DRO for a DBS receiver. Measurement results show that the phase noise is -92 dBc/Hz at the 10 KHz offset frequency, and from these results we have found out that the reduction method is very effective.

• Journal of the Korean Society for Library and Information Science
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• v.47 no.3
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• pp.343-361
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• 2013

We proposed and evaluated a tag semantic analysis method in which original tags are expanded and the semantic relations between original or expanded tags are used to extract key sentences from lecture speech transcripts. To do that, we first investigated how useful Flickr tag clusters and WordNet synonyms are for expanding tags and for detecting the semantic relations between tags. Then, to evaluate our proposed method, we compared it with a latent semantic analysis (LSA) method. As a result, we found that Flick tag clusters are more effective than WordNet synonyms and that the F measure mean (0.27) of the tag semantic analysis method is higher than that of LSA method (0.22).

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.87-88
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• 2014

조명용 LED의 보급확산에 따라 LED 구동용 전원장치에 대한 수요가 급증하고 있는데, 심각한 문제 중의 하나는 전원장치의 수명이 LED 수명에 비해 매우 짧다는 것이다. 이 문제를 해결하기 위해 전원장치에 포함되어 있는 전해커패시터를 없애야 한다. 또 다른 문제는 전원장치의 60Hz의 교류전원을 정류하여 회로를 구성해야 하는 특성상 120Hz 리플성분 때문에 플리커가 발생할 수 있다. 따라서 본 연구에서는 전해커패시터를 없앤 조명용 LED 전원장치를 제안하고 120Hz 리플성분에 의한 플리커를 최소화하기 위한 방안도 제시하고자 한다.

• Journal of IKEEE
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• v.24 no.2
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• pp.579-585
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• 2020

In this study, we used byte-inversion transmission method to prevent the flicker of lighting source in a visible light data communication link. In the transmitter, the non-return-to-zero (NRZ) signal with 9.6 kbps was on-off keying (OOK) modulated with a 100 kHz square wave carrier and byte-inversion signal was added after each byte to make the average optical power of the light-emitting diode (LED) constant. In the receiver, we used a band-pass filter to eliminate the interference of the 120 Hz noise which was induced from the adjacent light lamps, and an OOK demodulator to recover the original NRZ signal This scheme is useful in constructing wireless data networks using the illumination of visible light lamps.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.310-312
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• 2002

The development of IEC 61400-21 provides firm basis for assessment of the impact of wind turbines on voltage quality. This paper presents analysis and modeling of the flicker emission of wind turbines. The paper concentrates on the theoretical aspects of the flicker algorithm, wind turbine characteristics and the generation of flicker during continuous operation of wind turbines. It also introduces a simplified assessment to limit the flicker emission.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.360-363
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• 2011

카메라 촬영시 LED방송조명 등기구를 조도 디밍하는 경우에 카메라 셔터속도가 빨라 질 경우, 카메라가 신호를 감지하며 카메라 영상에 플리커 현상이 생기게 된다. 그 현상을 없어지게 하기 위하여 LED 디머의 PWM속도를 충분히 높여주어서 카메라 셔터속도가 빨라져도 어느 정도 범위에서 감지하지 못하도록 하였다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.05a
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• pp.71-73
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• 2003

본 논문에서는 RF Matcher 의 동작성능 개선을 위하여 RF Match 제어단의 제어 알고리즘과 하드웨어의 디지털화 방안에 대한 연구를 수행하였다. 개발된 제어단은 최적의 동작성능을 위하여 multi-preset, 이득제어 기능 등 다양한 부가 기능을 갖도록 설계/제작하였고, 또한 LCD 모듈의 설치를 통하여 RF Matcher의 실시간 상태 파악이 가능하도록 하였다. 개발된 제어단에 대한 실험결과로부터 RF 전력의 over/under shoot, 플라즈마 플리커 등의 현상이 제거되었고, 정합시간이 크게 단축되었음을 알 수 있었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.592-595
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• 2008

This paper presents development of automatic image quality register optimization system using mobile TFT-LCD (Thin Film Transistor-Liquid Crystal Display) driver IC and embedded software. It optimizes automatically gamma adjustment and voltage setting registers in mobile TFT-LCD driver IC to improve gamma correction error, adjusting time, flicker noise and contrast ratio. Developed algorithms and embedded software are generally applicable for most of the TFT-LCD modules. The proposed optimization system contains module-under-test (MUT, TFT-LCD module), control program, multimedia display tester for measuring luminance, flicker noise and contrast ratio, and control board for interface between PC and TFT-LCD module. The control board is designed with DSP and FPGA, and it supports various interfaces such as RGB and CPU.

• Journal of Digital Convergence
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• v.13 no.3
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• pp.209-214
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• 2015

Social network services such as Facebook and Flickr is a very useful service that was the foundation of the Internet. If a state in which the Internet is connected, music, photos, and us to be able to share it freely post such as documents. However, even when the digital information posted in such social network services the user has died, and have been published, it is also used for people who do not intend the bad purposes some problems can occur. Facebook is trying to apply the findings Jed R. Brubaker of UC Irvine University in order to solve this problem. However, in Korea, such efforts, not much appears for now. Therefore, we proposed a method that can be managed by delegated Facebook, safely a Delegator digital information posted on social networking services such as Flickr. Our proposed system, as compared with Jed R. Brubaker and Jeong-Kyung Moon is executed previous studies, we studied a method proposed by the appropriate compensates points shortage is passed through the future research. And I consider to have been proposed a method to safely use posted digital assets in a social network service.