• Proceedings of the Korean Information Science Society Conference
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• 2010.06a
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• pp.293-294
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• 2010

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.191.1-191
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• 2003

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1896-1899
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• 1997

In this paper, New radiation system is presented to improve efficiency and distribution of MWO. And it has one input for two excitatied lines with located on them radiation elements(slots). Radiation elements are distributed along the lines the way that the same electrical distances from the magnetron. New radiation system recompences change of impedance at wide b and frequency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.129-129
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• 2006

인쇄회로를 제작하기 위하여 기판상에 에칭 레지스트, 도금막, 절연재료, 솔더 마스크 등을 패터닝 하게 되는데, 일반적으로 이러한 유기체 막들은 대부분 액상이나 고형의 필름 형태로 패턴을 형성하게 된다. 형성된 패턴과 동박과의 접착력 향상이 가장 주요한 문제점 중의 하나이다. 상대적으로 편평한 동박면과 유기체 막과의 접착력을 향상시키기 위해 일반적으로 접촉 면적을 증가시키기 위한 표면개질을 하게 된다. 기계적 브러싱이나 스크러빙에 의해서도 기판상의 동박의 surface topography 를 개선하기 위한 노력이 시도 되고 있지만, 본 연구에서는 microetching 방법에 의해서 화학적으로 동박 표면상에 최대한 요철을 많이 형성하여 에칭 레지스트와 동박 간의 접착력을 증대시키기 위한 연구를 수행하였다.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.505-506
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• 2004

이어폰과 헤드폰의 성능 향상을 위해서는 특성에 대한 정확한 측정과 평가가 요구된다. 이어폰과 헤드폰은 room 과 같은 acoustic channel 을 거치지 않고 청취자의 귀에 직접 소리가 전달되며 ear canal 특성이 포함되기 때문에 스피커와는 다른 기준이 필요하다. 그러나 사람 귀의 canal 특성은 개인에 따른 편차가 심하여 정확한 측정 및 성능 평가에 어려움이 따른다. 본 논문에서는 이어폰과 헤드폰의 특성을 측정하는 적절한 방법을 고찰하고 측정된 데이터를 이용하여 음질 성능을 평가할 수 있는 객관적인 방법을 제시하고자 한다.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.283-286
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• 2004

Due to advances in electronics very high quality audio reproduction is today possible. But the listening environment causes deviation of the audio system from the expected behavior. Firstly the listening Room significantly changes the audio signal frequencies and their phase. Secondly the position of the user in the room affects the perceived sound. With existing DSP technology it is possible to adequately correct these effects. In our work we developed a room correction system, correcting up to 7.1 channels using dual Motorola 56367 fixed point DSP's, implementing position dependent room effects measurement, real time compensation filter design and equalization filtering procedures.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1108-1111
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• 2007

OLED driving voltage shift can reduce the OLED display lifetime, especially for digitally driven AMOLED. By operating OLED at high frequency, we were able to suppress OLED voltage shift degradation, expecting improved AMOLED lifetime. We describe frequency dependence of voltage shift obtained from bias stress test of OLED.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1030-1033
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• 2003

ZnS:Mn has been studied as a yellow phosphor for the application to fluorescent displays operated at low voltage. It was found that luminescence of $Mn^{2+}$ ion from hexagonal phase of ZnS was suitable for the display applications. The main emission peak was shifted to shorter wavelength when Cu ions were doped. The luminescence color of ZnS:Mn phosphor could be changed with decrease of its brightness.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1194-1198
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• 2006

For the purpose of developing more effective chelating agents, we have synthesized a diethylene triamine pentaacetic acid(DTPA) analogue by using an amino acid. S-(N-Boc-aminophenyl)-Cys(t-Bu4-DTPA) methylester was prepared in 6 steps with total yield of 47.9%. For the sake of introducing a biomolecule to the DTPA derivative, a selective hydrolysis was performed with 3 M HCl/Ethylacetate = 1 : 3 ($25{^{\circ}C}$, 30 min, vigorous stirring). $^{166}Ho$-Cys-DTPA and $^{166}Ho$-Biotin-Cys-DTPA were prepared by mixing $^{166}Ho$ with DTPA derivatives at room temp in a HCl solution (pH = 5) and the radiochemical stabilities (> 99%) were maintained for over 6 hrs in vitro.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.408-411
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• 1987

We have designed the power supply of an 120W $CO_2$ Laser for non-metal material processings. High voltage is automatically controlled by means of thyristor triggered phase control. Pulse and C.W. mode are selectively generated by means of discharge current control. It is possible to interface this system with other Numerical Controller. Also, safety interlock circuit is incorporated in this system.