• Journal of Astronomy and Space Sciences
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• 제8권1호
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• pp.73-83
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• 1991

조기형 근접쌍성 AQ Cas를 1982년부터 1989년까지 (총 91일 밤) 연세대학교 천문대 일산 관측소에서 관측하여 UBV 광도곡선을 완성하였다. U의 광도곡선으로부터 두 별사이에 물질이동으로 인하여 위상 0.55와 0.90근처에서 광도가 어두워지는 현상을 확인하였다. 우리의 관측점으로 4개의 식심시각을 결정하였고, 수집한 식심 시각을 가지고 새로운 광도요소를 얻었다. 또한, BV 광도곡선을 가지고 Wilson-Devinney 계산법으로 측광 궤도요소들을 구하였다.

• Journal of Astronomy and Space Sciences
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• 제15권1호
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• pp.75-82
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• 1998

A total of 842 observations (277 in B, 282 in V, and in R) for U Pegasi were made in October of 1996 at Mt. Sobaek Observatory. With our data we constructed the BVR light curves and determinded 5 times of minimum light. We also obtained physical parameters of the system by combined analysis of both light and radial velocity curves using the Wilson-Devinney code.

• 한국미생물·생명공학회지
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• 제21권5호
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• pp.435-439
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• 1993

For the overproduction of glutathione, Candida sp. mutant was isolated by the treatment with U.V. light. The highest glutathione production of Candida sp. mutant was obtained after shaking culture for 48 hours in the cullture medium containing glucose 1.5%(w/v), yeast extract 4.0% (w/v), KH2PO4 0.04%(w/v), biotin 5 ng/ml, and L-cysteine 0.04%(w/v). The optimal pH and temperature for the glutathione production were pH 6.0 and 25C, respectively.

• 천문학회지
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• 제27권2호
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• pp.133-146
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• 1994

We have detected a SiO maser line (v=1, J=2- 1) for 15 stars out of about 80 long period variables in the wide range of period. No new sources are detected; all detected sources are variables with period longer than 300 days; no evidence is found that the dust grains in the outer envelope have influenced on this line. The time variation of this maser line for 7 stars, T Cep, ${\mu} Cep$, U Her, R Leo, R Lmi, U Ori, and R Ser is observed and compared with optical light curve at the same epoch of maser observation. No universial relation between the time variation and the optical light curve is found. It implies that the radiation from a central star does not much play an important role for the direct pumping of the SiO maser line.

• KSBB Journal
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• 제9권4호
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• pp.378-384
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• 1994

KRF-OOI의 대량생산에 관한 연구를 수행하여 산 업화연구에 연결할 수 있는 자외선을 이용한 변이주 개발을 통해 모균주보다 약 2배 이상의 생산능이 높 은 lN4균주를 개발하였으며, 또한 10배까지 scale up한 발효를 통해 안정된 돌연변이주염을 확인할 수 있었다. HPLC를 이용한 KRF -001의 정성정량분석 방법을 개발함으로써 발효 중 harvest 시기를 정확 히 결정할 수 있였으며 대량발효에 따른 대량 분리 정제 방법의 전략을 수립할 수 있었다.

• 한국광학회:학술대회논문집
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• 한국광학회 2006년도 동계학술발표회 논문집
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• pp.209-210
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• 2006

• 한국균학회지
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• 제17권4호
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• pp.189-193
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• 1989

영지(靈芝)버섯 균사의 비자실체성(非子實體注) 담자포자(擔子胞子)의 형성(形成)에 미치는 광(光)의 영향을 구명(究明)하기 위하여 광질(光質), 광도(光度) 및 광조사(光照射) 시간(時間)을 달리하여 실험하였다. 영지(靈芝)버섯 균사의 비자실체성(非子實體注) 담자포자(擔子胞子)의 형성(形成)에 있어서 광(光)은 필수 요인이었다. 광(光)의 조사(照射)는 16시간 광(光)/8시간 암(暗)으로 계속 처리할 때 포자(胞子)의 형성량(形成量)이 가장 많았고 유효(有效)한 광(光)은 blue와 yellow이었으며 Near U.V.에서는 포자(胞子)가 형성(形成)되지 않았다. 광도(光度)는 백색광으로 1,000Lux일 때 가장 효과적(效果的)이었다. 광형태(光形態) 형성(形成) 반응(反應)은 계통간(系統間)에 명확한 차이를 보여 광(光) 요구성(要求性)이 유전인자(遺傳因子)의 지배를 받음을 보였다.

• 천문학논총
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• 제5권1호
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• pp.65-84
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• 1990

The temperature effects of the KNU UBV photometric system are investigated, using the HAMAMATSU 1P21 data. The variation of the passband width of V-band with temperature is about $5{\AA}/^{\circ}C$ while those of B-band and U-band are negligible. This large effect of V-band causes a significant variation of V-mag. and (B-V)-color with temperature such as ${\sim}0.02mag/^{\circ}C$ in both cases. This result strongly suggests that in the photometric observations of binary stars, the temperature effects of the response of photomultiplier and the passband of filters must be considered to avoid the systematic variation in magnitude and color particularly at the minimum of light curve.

• 전기학회논문지
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• 제56권1호
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• pp.112-116
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• 2007

We have investigated the hysteresis phenomenon of a hydrogenated amorphous silicon thin film transistor (a-Si:H TFT) and analyzed the effect of hysteresis phenomenon when a-Si:H TFT is a pixel element of active matrix organic light emitting diode (AMOLED). When a-Si:H TFT is addressed to different starting gate voltages, such as 10V and 5V, the measured transfer characteristics with 1uA at $V_{DS}$ = 10V shows that the gate voltage shift of 0.15V is occurred due to the different quantities of trapped charge. When the step gate-voltage in the transfer curve is decreased from 0.5V to 0.05V, the gate-voltage shift is decreased from 0.78V to 0.39V due to the change of charge do-trapping rate. The measured OLED current in the widely used 2-TFT pixel show that a gate-voltage of TFT in the previous frame can influence OLED current in the present frame by 35% due to the change of interface trap density induced by different starting gate voltages.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1038-1041
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• 2006

We report low operating voltage and long lifetime organic light-emitting diodes (OLEDs) with a vanadium oxide $(V_2O_5)-doped$ N,N'-di(1-naphthyl)- N,N'-diphenylbenzidine $({\alpha}-NPD)$ layer between indium tin oxide and ${\alpha}-NPD$. At a luminance of $1000\;cd/m^2$, $V_2O_5$ doped ${\alpha}-NPD$ device shows a operation voltage of 5.1V, while the device without $V_2O_5$ shows 5.8V. The $V_2O_5$ doped $({\alpha}-NPD)$ device also shows a longer lifetime and smaller operation voltage variation over time. It is suggested that the improved device performance can be attributed to the higher hole-injection efficiency and stability of the $V_2O_5$ doped $({\alpha}-NPD)$ layer.